Thursday, November 28, 2019
WordPress Chatbots How to Create Them, Plus Their Benefits
No matter how comprehensive your website is, your visitors will inevitably ask questions. Itââ¬â¢s best to answer those questions as quickly as possible, but you wonââ¬â¢t always be available. Thatââ¬â¢s where using WordPress chatbots can come in handy.Youââ¬â¢ve probably seen chatbots on other websites ââ¬â programs that can carry out basic conversations through text. While this may seem like a complex feature, adding a chatbot to your own site is surprisingly easy. You just need the right tool.In this article, weââ¬â¢ll explain how chatbots work and how they might be able to benefit your WordPress site. Then weââ¬â¢ll introduce some tools for adding WordPress chatbots, and show you how to start using them. Letââ¬â¢s go! Three tools for adding chatbots to your WordPress website1. BotsifyFirst up, we have Botsify. This tool is simple to use, even for beginners. Thereââ¬â¢s a drag-and-drop designer that makes building your chatbot interface simple, and plen ty of analytics options to help you refine your WordPress chatbots over time.Whatââ¬â¢s more, Botsify makes it easy to integrate your chatbot with WordPress. However, you will need one of the paid plans to create a website chatbot.2. WP ChatbotNext, letââ¬â¢s look at a WordPress-specific tool:WP Chatbot is one of the few chatbot plugins designed specifically for WordPress.Youââ¬â¢ll build your chatbot using the standard WordPress editor, with a few new options. WP Chatbot is also fully responsive and offers multiple design options. This is a premium plugin that costs $30 for a standard license.3. Watson AssistantFinally, if youââ¬â¢re looking for a more advanced option, Watson Assistant is worth considering:This solution offers both free and paid tiers, and enables you to build a chatbot with complex functionality.It will be able to understand when users switch topics or provide multiple pieces of information in one exchange, and respond appropriately. You can use this t ool to create WordPress chatbots using the IBM Watson Assistant plugin, which has few active installs but excellent reviews.Once youââ¬â¢ve chosen the right solution for your site, all thatââ¬â¢s left to do is actually create your chatbot. How this works will vary depending on the platform youââ¬â¢re using, but letââ¬â¢s look at one example.How to create WordPress chatbots with BotsifyIn this section, weââ¬â¢re going to show you how to create a chatbot using Botsify. Weââ¬â¢ve chosen this platform because itââ¬â¢s simple to get started with, and doesnââ¬â¢t require using a plugin.As we mentioned, you will need a paid account to create WordPress chatbots with Botsify. However, you can easily try the tool out via the free trial. After signing up, youââ¬â¢ll be sent an email with instructions on how to get started.After that, you can log into your account:You can either search for an existing template, which will fill in some of the details for you, or create a chatbot from scratch. To do the latter, click on the Chatbot for Website button. Give your chatbot a name, and select Create. You can then access the dashboard youââ¬â¢ll use to customize the chatbot:There are a lot of options here. First, select Basic Messages from the left-hand menu. This is where you can decide what your chatbot will say to introduce itself to new visitors:You can also use the Default message section to input a generic response the chatbot will use whenever someone asks a question it doesnââ¬â¢t understand.To start teaching your chatbot, youââ¬â¢ll want to visit the New Story section:Each ââ¬Ëstoryââ¬â¢ is made up of one or more potential user inputs, and a response from the chatbot. You simply enter keywords or phrases into the User says field, and then type the desired reply into the Bot says field. You can even add alternate responses, so the chatbot replies a little differently each time someone asks it the same question.At this point, you c an start teaching your chatbot, and check out the documentation if you get stuck. When youââ¬â¢re done, you can embed the chatbot into your WordPress site by adding a little code to your footer.php file:Itââ¬â¢s worth noting that most chatbot tools work in a very similar fashion. So if Botsify isnââ¬â¢t to your liking, youââ¬â¢ll already be a step ahead when you try out another solution.ConclusionAdding a chatbot to your website is a little like hiring a part-time employee. Your chatbot can welcome visitors, answer some of their basic questions, and direct them to wherever they need to go (such as your contact page). This is a smart, easy way to improve the user experience on your site.To create WordPress chatbots, youââ¬â¢ll need a dedicated solution. Here are a few you can try out:Botsify: A reasonably-priced, flexible chatbot tool that is easy to get started with.WP Chatbot: A premium WordPress plugin that simplifies adding a chatbot to your site.Watson Assistant: A more advanced option with a lot of functionality and analytics options.Do you have any questions about how to use WordPress chatbots effectively? Drop us a line in the comments section below! "Hey Google - how can I create #WordPress #chatbots?" By following this tutorial
Monday, November 25, 2019
How to Use the Internet as a Reporting Tool
How to Use the Internet as a Reporting Tool At the risk of sounding like an old fogey, let me explain what it was like to be a reporter in the days before googling was a verb. Back then, reporters were expected to find their own sources and interview them, either in person or over the phone (remember, before the internet, we didnt even have email). And if you needed background material for a story, you checked the newspapers morgue, where clips from past issues were kept in filing cabinets. Or you consulted things like encyclopedias. Nowadays, of course, thats all ancient history. With the click of a mouse or a tap on a smartphone, journalists have access to virtually unlimited amounts of information online. But the strange thing is that many of the aspiring reporters I see in my journalism classes dont seem to know how to appropriately use the internet as a reporting tool. Here are three main problems I see: Relying Too Heavily on Material From the Web This is probably the most common Internet-related reporting problem I see. I require students in my journalism courses to produce articles that are at least 500 words, and every semester a few submit stories that simply rehash information from a variety of websites. But there are at least two problems that arise from this. First, youre not doing any of your own original reporting, so youre not getting important training in conducting interviews. Second, you run the risk of committing plagiarism, the cardinal sin in journalism. Information taken from the internet should be a complement to, but not a substitute for, your own original reporting. Any time a student journalist puts his byline on an article being submitted to his professor or the student newspaper, the assumption is that the story is based mostly on his own work. By turning in something thats largely copied off the internet or not attributed properly, you are cheating yourself out of important lessons and running the risk of getting an F for plagiarism. Using the Internet Too Little Then there are students who have the opposite problem - they fail to use the internet when it could provide useful background information for their stories. Lets say a student reporter is doing an article about how rising gas prices are affecting commuters at her college. She interviews plenty of students, getting lots of anecdotal information about how the price rise impacts them. But a story like this also cries out for context and background information. For instance, what is happening in global oil markets that are causing the price increase? What is the average price of gas across the country, or in your state? Thats the kind of information that can easily be found online and would be perfectly appropriate to use. Its laudable that this reporter is relying mostly on her own interviews, but shes short-changing herself by ignoring information from the web that could make her article more well-rounded. Failing to Properly Attribute Information Taken From the Web Whether you are using online sources a lot or just a little, its crucial you always properly attribute the information you use from any website. Any data, statistics, background information or quotes that you havent gathered yourself must be credited to the website it came from. Fortunately, theres nothing complicated about proper attribution. For instance, if you are using some information taken from The New York Times, simply write something like, according to The New York Times, or The New York Times reportedâ⬠¦ This introduces another issue: Which websites are reliable enough for a reporter to use, and which sites should she steer clear of? Fortunately, Ive written an article on that very topic, which you can find here. The moral of this story? The bulk of any article you do should be based on your own reporting and interviewing. But any time you are doing a story that could be improved with background information on the web, then, by all means, use such information. Just make sure to properly attribute it.
Thursday, November 21, 2019
Using Teams in Production and Operations Management Essay
Using Teams in Production and Operations Management - Essay Example A fundamental accountant should be conversant with information research and gathering (Pedneault, Rudewicz, Silverstone & Sheetz, 2012). This skill is very important in the field of forensic accounting because to be able to undertake an investigation the accountant will first have to obtain all the information concerning the company. It is also needed since if for example conducting a research about fraud, the forensic accountant should be able to find all the information about the auditors of the company, the management and all other people concerned with the financial matters of the company. The relationship between this skill and its application in the business is that since a business is conducted by a large number of people and contains a wide range of information, it will thus require a forensic accountant who can search for the information. Analytical; a second skill to be possessed by a forensic accountant is the skill of analysis. He or she should be able to analyze data items critically and all information gathered should be scrutinized keenly to come up with all the minor details which might be taken for granted. This skill is needed since it enables the accountant obtain results which are not compromised. He or she will also be able to maintain high standards of accuracy in his work. This skill is very important in business operations because, fraud in a company is usually carried out by highly qualified people and thus they will use all ways to hide this fraud. Thus, to identify it, the forensic accountant will need to conduct and in-depth analysis. Investigative and communicative skills; a forensic accountant should be able to conduct a thorough investigation on all people concerned with the work being investigated. This is only possible if he or she has good communication skills; where he can question people without hurting their feelings or harassing them. He should not be
Wednesday, November 20, 2019
Evidence Based Practice Article Example | Topics and Well Written Essays - 750 words
Evidence Based Practice - Article Example It was intended to identify the following issues at this moment divided into general objective and specific objectives under such subheadings. There exist modifiable and non-modifiable risk factors in addition to other factors contributing to the prevalence of Ventilated-Associated Pneumonia with modifiable risk factors being; education of personnel, surveillance and reporting, transmission prevention, and modification of host risks. It was realized that education of personnel regarding the ventilator-associated pneumonia reduction strategies reduces the incidence of the same (Coffin, 2008). It was found out that Surveillance and reporting of ventilator-associated pneumonia to certain extend help to track and identify the major causes of Ventilated-Associated Pneumonia. Vaccinations of all healthcare workers and high-risk peoples in the community is a priority in the prevention of community-acquired and healthcare-acquired pneumonias especially after it was realized that the prevention of transmission of pneumonia from person-to-person is a major modifiable risk factor that could be achieved by proper hand-washing and use of gloves and gowns. Modification of host risks was also found to reduce Ventilator-Associated Pneumonia. This includes; increasing host defenses against infection and prevention of aspiration, as well as the use of noninvasive positive-pressure ventilation. The latter was also found to help in reducing the incidence of Ventilator-Associated Pneumonia. It was also found that an oral intubation route is preferred over nasal intubation to prevent sinusitis and decrease the risk of contracting in most hospitals (OKeefe-McCarthy, 2008). Supporting and maintaining a patients head-of-bed angles at 30 to 45 degrees or higher could be a good preventative strategy against aspiration of gastric contents. This plus the use of turning or
Monday, November 18, 2019
Resume Assignment Example | Topics and Well Written Essays - 500 words - 3
Resume - Assignment Example My previous work experiences entail dealing directly with people through administering functions and through managing organizational campaigns. I am highly skilled in undertaking effective communication, in various medium. I am an exemplary team player and could work in diverse environments; even in demanding or highly challenging situations. My ability to discern appropriate conflict negotiating techniques, as well as apply problem-solving strategies, make me highly competent for the position. Likewise, my aviation knowledge and skills would be a potential advantage for an Air and Marine Interdiction Agent, in the near future. I am hereby attaching my resume for your perusal. I would be available for interview at your most convenient time. I could be reached in any of the stipulated contact details. I am confident that when considered for the position, we would be establishing a mutually beneficial business relationship. I would be looking forward to hearing from you
Friday, November 15, 2019
Characterisation of Prostate Cancer Stem Cells
Characterisation of Prostate Cancer Stem Cells Abstract Background Advances in the study of cancer cells with stem cell characteristics may enable the development of new and improved cancer therapies. Stem cell marker expression can be investigated by QPCR and this sensitive method has been used to characterise prostate cancer stem cells. Methods Prostate cancer cell lines LNCaP and C42B were grown under adherent and nonadherent culture conditions. Non-adherent culture generated prostaspheres that are enriched in stem cells. In addition, LNCaP and C42B prostaspheres were treated with Wnt3a. RNA was extracted from both adherent and prostasphere cultures of LNCaP and C42B cells. cDNA was synthesized and QPCR analysis was performed with TaqMan probes in order to examine the expression of 10 genes: Nestin, Oct4, Sca-1, BMI-1, PSA, NSE,CD44, K18, ABCG2 and c-kit. Results Prostasphere culture caused a dramatic increase in the relative expression of ABCG2 and Keratin 18 in both cell types. Conclusion The findings suggest ABCG2 may be a valuable marker for identification of prostate cancer cells with stem cell characteristics. Moreover this technique of Q-PCR may prove to be a sensitive method of evaluating markers in cancer patients. Introduction Prostate cancer is commonly diagnosed in males over 60 and is the second most common cause of cancer death in UK in men, after lung cancer (1). Following diagnosis, prostate cancer is categorised in low risk, intermediate risk and high risk. For low risk cases treatment is usually under active surveillance while intermediate and high risk is treated by surgery and radiation. Advanced cases (presence of metastasis) treatment is by androgen ablation and it almost always produces objective clinical responses (2). However, in most patients there is relapse with the development of androgen independent prostate cancer, which is associated with a median survival, of 20ââ¬â24 months (3). Currently, androgen independent metastatic prostate cancer is treated by Docetaxel an anti-mitotic that extends life by an average of 3 months (3). Although, the mechanisms of prostate cancer development and progression have been extensively studied this process is not fully understood. Several genes including MYC and PTEN have been linked to the development of prostate cancer (28). However, one of the most important discoveries in the genetics of prostate cancer is the identification of TMPRSS2-ETS fusion protein that arises as a result of a genetic translocation (4). TMPRSS2 is androgen-regulated transmembrane serine proteases secreted by normal prostatic tissue and an increase in androgen level increases TMPRSS2 expression. ETS family transcription factor (ERG, ETV1, or ETV4) targets genes involved in cell transformation, growth and apoptosis. Therefore fusion of TMPRSS2 gene promoter with one of the member of ETS family results in positive dysregulation of the ETS gene. TMPRSS2-ETS fusion proteins have been speculated to play a role in the development of up to 50% of prostate cancers but not the progression to androgen independence (4). Androgen independent prostate cancer has been postulated to arise as a consequence of increase activity of the androgen receptor (AR), altered cell signalling pathways, or the survival and proliferation of prostate cancer stem cells. Recent papers have conceptualized that cancer can arise from cancer cells with the characteristics of stem cells, unlimited self-renewal and the ability to produce differentiated daughter cells (5). These cells have been termed cancer stem cells (10) and may promote tumour growth, metastasis and relapses, thus having a huge impact on patient survival. The cancer stem cell model hypothesis is that cells with stem cell characteristics accumulate genetic changes over long period of time, escape the environmental control and give rise to cancerous growth. There is good evidence that cancer stem cells cause leukaemias and it has also reported that cancer stem cells can contribute to solid tumour development in brain, breast, colon and prostate. As prostate cancer is a heterogenic disease, several distinct cancer stem cell populations maybe present in a tumour (5). On basis of this knowledge, the role of cancer stem cell is been explored in solid tumours. For instance in prostate cancer mutation of the androgen receptor may result in the growth of tumour that can sustain androgen deprivation or very low level of androgen or use alternative pathways involving growth factors and cytokines. Recent studies (6) have also identified mammary stem cells as being a potential source of breast cancer, tumour relapse and tumour metastasis. For this reason it is vital to understand the stages of cell differentiation in normal prostate epithelium and identification of cells that are involved in prostate carcinogenesis and androgen independent prostate cancer. The prostate is a glandular organ comprising of three distinct epithelial cell populations that may contribute to tumorigenesis (7). Each prostatic duct is lined by nonsecretory basal cells which form a layer along the basement membrane (figure 1). Luminal cells are the major secretory cell, producing 30% of seminal fluid components and lining the lumen of duct and acini. These luminal cells are highly differentiated and expresses prostate specific antigen, cytokeratin 8 and 18 and the nuclear androgen receptor (27). Neuroendocrine cells are also present along the basement membrane and secrete neuroendocrine peptides that support epithelial growth and viability. Vascular components and stromal endothelial cells are also present in the gland. Figure 1. Schematic presentation of the cell types within a human prostatic duct. (Adapted from Abate-Shen, C. Shen, M et al 2000) Recent evidence has suggested stem cells are also present within the prostate cancer cell population. It have been theorized that stem cells may lie in the basal layer of prostate in man and in the basal and luminal compartments in mice (19). A transient amplifying population of daughter cells arises from these stem cells and generates differentiated PSA producing cells in man. Stem cells can have different characteristics, including resistance to apoptosis and increased expression of multidrug resistant transporters (8, 23, 24, 25 ). The findings of Collins et al 2001 (9) revealed that stem cells can be distinguished from the transient amplifying cells and showed there is 2-3 fold increases in expression of surface level of integrin à ±2à ²1. Figure 2. Hypothetical model of stem cells showing normal prostate development and prostate cancer (De Marzo MA et al 1998). De Marzo MA et al 1998 in his paper states pluripotent stem cells are capable of differentiation and self-renewal and is present in the basal epithelium of the prostate, which contains cytokeratin 5 and 14 expressing cells (figure 2). Intermediate progenitor populations located within the basal epithelium expresses both basal and secretory cell characteristics (11). Intermediate cells with limited proliferative capacity can differentiate into mature secretory luminal (androgen receptor positive) or neuroendocrine cells which are non-proliferative. In prostate cancer, it is proposed that transformation occurs which leads to the proliferation of cells with stem cell characteristics and the production of an excess of cells with luminal characteristics (Bisson and Prowse 2009). Normal murine prostate stem cells have been functionally identified by their ability to form prostate spheres (13) and to form differentiated prostate tubular structures when returned to an in vivo environment (13, 14). The in vivo generation of prostate structures from normal human prostate cells in xenograft studies and the ability to isolate a human basal prostate cell population with enriched capacity for prolonged clonal expansion and luminal differentiation have led to the hypothesis that normal human prostate stem cells are located within the basal layer of the gland (15-18). English HF et al 1987 (19) in an experiment found following androgen ablation of rodent prostate glands the stem cells exhibited regenerative properties especially of the secretory cells indicating these cells are self- sustainable, which supports the hypothesis that stem cells reside within the basal layer of the gland and are able to survive in absence of androgen environment. These cells may also therefore have the ability to survive androgen deprivation therapy and contribute to the development of metastatic prostate cancer. At present proper characterization of stem cells has been limited by the absence of specific markers that distinguishes stem cells from their more differentiated progeny. Gene expression and microarray profiling may be able to identify specific markers. These markers may also be prognostic for patient response to therapy and survival. Past papers have discussed non-adherent culture media techniques to isolate neuronal, colon and breast cancer cells that exhibited stem cell characteristics. In a recent paper by Bisson and Prowse et al 2009 (10) the authors studied prostate cancer cell lines (22RV1, DU145, PC3, VCaP, LNCaP and the LNCaP subline C4-2B) and were able to form prostosphere in non adherent culture conditions. Prostosphere were able to form from both AR positive (LNCaP, VCaP, 22RV1) and AR negative (PC-3, DU145) cell lines. Analysis of marker protein expression of proliferation (ki67) and differentiation (keratin 18 and PSA) of prostosphere revealed that cell heterogenecity existed within the prostaspheres, which may be due to different percentages of stem cells within the cell lines or maybe related to adaptation to their environment in the nonadherent culture conditions. Immunoflourescence (Figure 4) of these prostospheres with stem cells associated markers (CD44, CD133, ABCG2) showed increase in expression compared with the adherent cultures, consistent with enrichment for stem cells. However this analysis was only performed by immunofluorescence, and was limited by the semi-quantifiable nature of this technique and the antibodies available (10). Aim Quantitative analysis of cells with stem like characteristics in prostate cancer has not been attempted yet. The aim of my project is therefore, quantitative PCR (QPCR) analysis of stem cells associated gene expression of the prostosphere compared to that of the adherent culture. Material and Methods For my project I used the prostate cancer cell lines DU145, LNCaP and the LNCaP subline C4-2B. The prostasphere formation (P0) is highest in the cell types of LNCaP and its androgen independent derivative C42B, which both express AR and PSA (23). I conducted my experiments by real time PCR to measure the mRNA level of expression on cDNA extracted from prostasphere of LNCaP and subline of LNCaP, C42B cell line. This assay is both qualitative and quantitative and allowed me to compare the RNA gene expression in relation to the control (GAPDH). However there are certain limitations of using this method in my experiment. The prostasphere is heterogenic and the stem cell population within probably only a small fraction of the cells. Therefore it will be interesting to see how this affects the gene expression of the mRNAs. Cell Culture Prostate cancer cell lines LNCaP, C42B and DU145 were cultured at 37à °C in RPMI using 10% fetal bovine serum (Invitrogen), 2.4 mM glutamine (Sigma-Aldrich), 1% (v/v) pyruvate (Sigma-Aldrich), penicillin and streptomycin (50 U and 50 à ¼g/ml) (Invitrogen). Trypsin (Sigma-Aldrich) was used to detach adherent cells, prior to cell counting, passage or analysis (10). Prostasphere cultures were established on low attachment 6-well plate (Costar) when single cells were plated in DMEM/F12 (Invitrogen) supplemented with B27 and N2 (Invitrogen) and grown under these conditions for 6-12 days (Bisson and Prowse 2009). These proliferating spheres of cells are enriched for stem cells (Bisson and Prowse 2009) and were prepared for these experiments by Dr Prowse. The prostasphere medium was also supplemented with WNT3a at 20à µg/ml (RD Systems) and the Hedgehog pathway inhibitor cyclopamine for 6 days prior to analysis. RNA Extraction RNA was extracted from prostate cancer cell lines LNCaP, C42B and DU145 cells (stored at -70à °C and thawed at 37à °c before extraction) using RNeasy Kit (Superscript II enzyme and Poly-A primer) from Qiagen. 600à µl of RLT Plus (10à µl of à ²-mercaptoethanol was added to 1ml of RLT Plus buffer prior to the experiment) was added to the cells. The lysate was then added to the QIAshredder spin column sitting on a 2ml eppendorf and centrifuged for 2 minutes at maximum speed (14000 x g). The flow through was transferred to another tube and an equal volume of 70% ethanol was added and mixed by pipetting several times. 700à µl of the samples was added to a RNeasy spin column and centrifuged for 15 secs for 14000 x g. The flow through was discarded and 700 à µl of buffer RW1 (supplied) was added to the spin columns and centrifuged for 15 secs at 14000 x g. The flow through was discarded and the column was placed on a new collection tube. 500 à µl of buffer RPE was added to the column and centrifuged for 2 minutes to dry the RNeasy membrane. To further dry the membrane the column was placed on another tube and centrifuged at maximum speed for one minute to completely dry the column and to remove the trace of RPE buffer. The column was then transferred to another collection tube and 30 à µl of RNAse free water was added. Finally the tube was centrifuged for one minute (14000 x g) and the elute collected. The RNA was stored at -80à °C freezer (detailed protocol attached in Appendix). Reverse transcription c-DNA synthesis was done by using SuperscriptTM III First-Strand Synthesis System for RT-PCR. According to the manufacturerââ¬â¢s instruction 2 à µl (2 à µg) of previously prepared RNA was added to 1à µl of 50uM oligo (dT)20, 1à µl of 10mM dNTP mix in a tube and DEPC-treated water added to make a volume of 10 à µl. The reaction tube was incubated at 65à °C for 5 mins and then placed on ice for one min. In another tube 2 à µl of 10X RT buffer, 4à µl of 25mM Mgcl2, 2 à µl of 0.1DTT, 1 à µl of RNaseOUTTM (40U/ à µl) and 1 à µl of SuperScriptTM III RT (200 U/ à µl) was added. The 10 à µl mix of the first tube was added to the second tube and incubated for 50 mins at 50à °C. The reaction was terminated by incubating at 85à °C for 5mins and then chilled on ice. 1 à µl of RNase H was added to the tube and incubated for 20 mins at 37à °C. The total yield of cDNA was 25 à µl and this was stored at -20à °C till further use. Polymerase Chain reaction Polymerase chain reaction was carried out on the cDNA synthesized, using GREX-f* primer GAGTACCTCTGGAGGACAGA and GRINTRON-r* primer ATGCCATTCTTAAGAAACAGGA. For each reaction 5 à µl of 10xPCR buffer II, 3 or 6 à µl of 25mM MgCl2, 4 à µl of 10mM dNTP, 1 à µl of forward and reverse primer at 10 à µM and 0.25 à µl of AmpliTaq Gold Enzyme were mixed in a tube. cDNA at 10 ng/à µl was added to the reaction tube and made upto 50 ul with deionised water. The reaction was run at 94à °C for 6 min, and then 35 cycles of 94à °C for 30 secs, 55à °C for 30 secs, 68à °C for 30 secs, 72à °C for 30 secs followed by 72à °C for 6 mins. Gel Electrophoresis In order to see the purity of the cDNA synthesized (not contaminated with genomic DNA) gel electrophoresis was carried out. 2% Agarose Gel was prepared with TBE and cyber red added as a fluorescent tag. The gel was poured on a gel plate and a comb was inserted and ran for 30mins at 90V. Relative Quantitative PCR In real-time quantification technology the TaqMan MGB probes contain: â⬠¢ A reporter dye (6-FAM) linked to the 5à ´ end of the probe. â⬠¢ A minor groove binder (MGB) that increases the melting temperature (Tm) without increasing probe length (Afonina et al., 1997; Kutyavin et al., 1997); it also allow the design of shorter probes. A nonfluorescent quencher (NFQ) at the 3à ´ end of the probe 5à ´ Nuclease Assay Process A TaqMan probe contains a reporter dye at the 5à ´ end and a quencher dye at the 3à ´ end of the probe. The DNA polymerase cleaves the TaqMan probe during PCR and separates the reporter dye and quencher dye. This cleavage results in increased fluorescence of the reporter dye (26). Figure 3.TaqManà ® probes require a pair of PCR primers in addition to a probe with both a reporter and a quencher dye attached. When the probe is cleaved, the reporter dye is released and generates a fluorescent signal (Invitrogen). The reporter dye does not fluoresce if the probe is intact. During PCR, if the target of interest is present, the probe specifically anneals between the forward and reverse primer sites. On the other hand if the probe hybridizes to the target the DNA polymerase cleaves the probes between the reporter and quencher. The fragmented probes then separate from the target of interest and further polymerisation of the strand continues (26). For quantification of the change in expression of mRNA the ABI 7500 was used to perform the thermal cycling, data collection and data analysis. In a MicroAmp 96 well plate (Applied Biosystem) 10 à µl of final volume of TaqMan mix was placed. The mixture included 5à µl of TaqMan Gene Expression Assay, 0.5 à µl of the primer, 0.5 à µl of GAPDH (endogenous Control) and 4 à µl of 1:3 diluted samples. Prior to this study Ct value (cycle threshold) with a standard curve (Fig 5) was constructed and the primer and GAPDH concentration were determined by optimisation studies. All the primers were purchased from applied biosystem and are listed in Table 1. Using the ABI 7500 system the PCR was carried out at 50à °C for 2 min, followed by 95à °C for 10 mins. Then 40 cycles of 95à °C for 15 secs and 60à °C for 60 secs were performed. Mean relative quantification (RQ) was evaluated using the à ¢Ãâ â⬠à ¢Ãâ â⬠Ct method using GAPDH as endogenous control. Prior to analysis the PCR products were run on a 2% agarose gel to confirm that the templates have amplified along with GAPDH as endogenous control (figure 5). DATA Analysis The data generated from the RT-PCR were analysed using the recommended threshold by Applied Biosystem and then exported in Excel format. For calibration and generation of standard curves several cDNA cell lines were used: cDNA from DU145, LNCaP and C42B. The slope of the standard curve was calculated from the log input of cDNA in ng/à µl versus the corresponding Ct value. Basic statistical analysis was performed in Excel. Results Cell Culture Dr Prowse used a non adherent technique suspension culture and identified a group of cells within the prostate cell lines 22RV1, DU145, PC3, VCaP, LNCaP and C42B that had the ability to form prostasphere (Figure 4a). Furthermore using the clonal growth assay, each prostasphere was able to grow a further 1-3 prostaspheres (5b) when dissociated to single cells (10). These prostasphere along with prostate cell lines were used in this study. Immunoflourescence conducted by Dr Prowse on the prostate cancer spheres derived from single cells are illustrated in Figure 4A. Figure 4. Representation of prostasphere formation, culture and the effect of Wnt3a on Keratin 18, CD44 and ABCG2. A) Prostasphere shows self renewal and proliferation and this is a schematic representation of this process. B) Prostasphere formation with 0.1% DU145, 8% LNCaP and 8% of C42B cell lines. C) Effect of Wnt3a on keratin 18, CD44 and ABCG2 (Bisson and Prowse et al 2009). RNA extraction and RTââ¬âPCR Upon RNA extraction of the cells lines and prostospheres the concentrations were measured by spectrophotometer. It was 234ng/à µl for C42B and 190ng/à µl for DU145 respectively. A PCR was conducted with glucocorticoid receptor gene intron primers and gel electrophoresis was carried out to verify the purity of the samples. Only genomic cDNA of LNCaP and Hela cells amplified under 3 mMMg++ conditions (Figure 5). Figure 5. A) Results of quantitative RT-PCR analysis. The PCR in Lanes 1-5 contained 1.5mM Mg++ and lanes 6-10 contained 3mM Mg++. (B) A 2% gel was run with the PCR products that were amplified in Real Time PCR. Lane 1 represented BMI-1, lane 2 NSE, lane 3 ABCG2, lane 4 Nestin, lane 5 K18, lane 6 CD44, lane 7 OCT4, lane 8 PSA, lane and lane 9 sca-1.In all the lanes except lane 8 a double band was observed. The two bands represented GAPDH and the gene of interest. For construction of a standard curve, serial dilutions (1ng/ à µl, 5ng/à µl, 20ng/ à µl and 50ng/ à µl) of cDNA were used. In all cases, there was a strong linear correlation between the number of thermal cycles required to generate a significant fluorescent signal above background and the log of the input cDNA amount (correlation coefficient âⰠ¥ 0.90) (Figure 6). The Ct value was against the log of the initial template amount and subjected to linear regression analysis. Figure 6. Real time RT-PCR: standard curves for cDNA obtained from LNCaP, C42B and DU145 cell lines at 1ng/à µl, 5 à µl, 20 à µl and 50 à µl . A strong linear correlation between the CT values and the log of the input cDNA amount (correlation coefficients ranging from 0.97 to 1.0) were obtained. Quantification and Comparison of the Real Time Quantitative RTPCR results between Adherent cells untreated Prostasphere and treated Prostasphere. Delta Ct values for adherent cells and their correlation with those for prostasphere treated and untreated samples showed high correlation (r 2 âⰠ¥90) emerged for all of the tested genes ( Figure 6). GAPDH was used as endogenous control. In order to quantify the gene expression of the prostasphere and treated prostasphere (wnt3a and cyclopamine) to adherent cells (C42B and LNCaP), 10 markers were compared by Q-PCR using GAPDH as endogenous control (Fig 8). The PCR products were resolved on a 2% gel to confirm the templates have amplified along with GAPDH as endogenous control (Figure 5). Duplex product was seen in most of the lanes. The method of calculation was by à ¢Ãâ â⬠à ¢Ãâ â⬠Ct method. This method calculates the fold change in respect to the normalized gene. In our study we have compared the fold changes of gene expression of the treated and non treated prostosphere relative to the cell line (C42B and LNCaP). In the table (Table 2) we calculated delta delta Ct in relation to the cell line. Each of the samples were run in triplicates, therefore an average of those three were taken in each cases. For example for C42B spheres, the Ct values are 30.19, 29.92, and 30.27. The average of this was taken (30.19, 29.92, 30.27)/3 which is 30.13 and the same was calculated for GAPDH which is 18.94. In each case that is sphere, C42B wnt3a treated, C42B control (dissolved in DMSO) and spheres treated with cyclopamine the average Ct was calculated. Table 2. Example of calculation for quantification of gene expression in fold changes. Sample Average Ct a of samples b Average Ct of GAPDH à ¢Ãâ â⬠Ct à ¢Ãâ â⬠à ¢Ãâ â⬠Ct RQ Values d Prostasphere 30.13 18.94 11.19 -2.01 4.04 Prostasphere +Wnt3a 31.20 19.75 11.46 -1.74 3.34 Prostasphere control 33.97 22.7 11.27 -1.93 3.82 Prostasphere+ cyclopamine 30.28 19.43 10.9 -2.35 5.09 Adherent Cells c 13.20 0 1 a.Cycle threshold. b.Prostasphere, Prostasphere+wnt3a, Prostasphere control, Prostasphere +cyclopamine. c. For adherent cells the à ¢Ãâ â⬠Ct value was calculated from the standard curve. d. Relative quantification or fold changes. à ¢Ãâ â⬠à ¢Ãâ â⬠Ct was calculated by subtracting the Ct of the endogenous control (GAPDH) from the Cts of the gene of interest eg 30.31-18.94=11.19. Fold changes are calculated relative to the adherent cells. Therefore à ¢Ãâ â⬠à ¢Ãâ â⬠Ct is calculated by subtracting the à ¢Ãâ â⬠Ct value of the adherent cells from the à ¢Ãâ â⬠Ct of the sample i.e.11.19-13.20=-2.01. Relative quantification (RQ) value of gene expression was calculated by the use of the equation RQ= 2-à ¢Ãâ â⬠à ¢Ãâ â⬠Ct RQ=2-(-2.01) Therefore an RQ or fold change relative to the adherent cells is 4.04. Figure 7. Q-PCR analysis of the mRNA levels of Nestin, Sca-1, Oct4, BMI-1, NSE, K18, PSA, CD44, ABCG2 and c-kit. Expressions of the markers were calculated by employing the ÃâÃâCt method. (A) Nestin expression was decreased in prostaspheres in C42B adherent cell, prostasphere treated and untreated and were insignificant. (B). Effect of Sca-1 on C42B was unchanged between adherent cells and the prostaspheres. However in LNCaP a modest increase was observed. (C) The prostasphere expressed nearly two fold increase in expression. (D) Oct4 expressed about four fold increase in prostasphere treated samples (Wnt3a and cyclopamine). (E) In LNCaP Oct4 expression is reduced in Wnt 3a treated prostasphere. (F) In C42B prostasphere and Wnt3a treated prostasphere BMI-1 showed slight increase in level of expression. (G) However this change is not as pronounced in LNCaP. (H) NSE marker shows very high expression for C42B prostosphere control and marked reduction when treated with cyclopamine. (I) In LNCaP, no such change was observed between Prostasphere and Wnt3a treated prostasphere. (J and K) Keratin 18 shows extremely high levels in prostasphere with reduction when treated with Wnt3a or cyclopamine. (L and M) PSA failed to show significant changes in the level of expression. Although wnt3a and cyclopamine treated samples showed slight reduction. (N and O) CD44 was not expressed in both C42B and LNCaP prostosphere. However the adherent cells had high expression of the marker. (P) ABCG2 shows high expression of prostasphere in C42B. Wnt3a treated spheres showed reduced levels. (Q) In case of LNCaP extreme level of expression of ABCG2 was observed in prostosphere. (R) c-kit/CD117 was expressed more in the prostasphere with reduced expression on the Wnt3a treated and cyclopamine treated samples. Nestin and CD44 showed significant reduction in expression compared to the adherent cells of C42B. Nestin expressed less than 1% in prostasphere (figure 8A,) and negligible expression of CD44 (figure 7N) in C42B. There is increase in expression of SCA-1, OCT4, BMI-1, K18, ABCG2 and C-KIT (Figure 7 B, C, F, J, K, p, Q and R). NSE showed significant increase (Figure 7 H) in prostasphere control (97% more expression than adherent cells) and 100% increase in expression of K18 prostasphere(Figure J and K) and 100% increase expression of ABCG2 in prostasphere, prostasphere treated with cyclopamine treated and control. Interestingly Wnt3a treated prostasphere showed reduced expression of ABCG2 (Figure 7 P and Q). In LNCaP expression of CD44 is insignificant (0.01%) and PSA expression is reduced by 40% (Figure O and M). In case of LNCaP there was 18% increase in expression of SCA-1, 16% of BMI-1, 50% in NSE, 100% in case of Keratin 18 (Figure 7 C, G, I, and K). A summary of the results are shown in table 3. Table 3. Comparison of fold changes in mRNA expression in 10 selected genes determined by real-time quantitative polymerase chain reaction (RT-qPCR). Discussion Collins et al 2005 (41) in their paper states tumour cells are organised as hierarchy that are responsible for the formation of cancer. They have been able to identify and characterise cancer cell population from prostate tumours that have the ability of cell renewal and regenerate expressing differentiated cell products. Various studies have developed non-adherent sphere culture to characterise cancer cells with stem cell like characteristics. In vitro culture in unattached conditions where cells grow in round balls called spheres is routinely used for enrichment and propagation of stem cells (40). Prostate cancer is a heterogenous disease and to study the prostate cancer cells with stem cell characteristics prostasphere were cultured by Dr Prowse. Previous papers have established stem cell markers namely CD44+, CD133, ABCG2, à ±2à ²1 integrin, Sca-1 and à ²-catenin and PSA can be utilized to identify stem cell population in normal prostate (29,30).However the role of CD117 is yet to be defined in human. Figure 8. The self renewal capacity of cells with stem cell characteristics and the proliferation/differentiation of transit amplifying cells are regulated by WNT signalling. In addition AR activity is the driving force behind proliferation and differentiation of the transit amplifying cell. à ²-catenin which is also an effector of WNT signaling can interact with the activity of AR (Bisson and Prowse et al 2009). In the paper by Bisson and Prowse (10), the authors provide evidence that in absence of AR, WNT activity can control the cell renewal capacity of the prostate cancer cells with stem cell characteristics. On basis of their conclusion they suggested a model (figure 2) where the balance of WNT and AR activity not only regulates the self renewal of prostate cancer cells with stem cell characteristics but also the proliferation and or differentiation of the transit amplifying cells. In my study I tried to characterise the stem cell population within the prostate using different stem cell and differentiation markers and measuring their relative gene expression. This evidence can be used to further charaterise tumour stem cells: as they may comprise only a fraction of the cells responsible for the tumour, and have the abilities of self renewal, proliferation and differentiation. Nestin a neuronal marker, is an intermediate filament protein that identifies progenitor cells in adult tissues. Previous papers (31) have provided evidence of detectable levels of Nestin mRNA and these levels were increased in case androgen-insensitive prostate cancer cell lines (DU145). They were undetectable in the androgen dependent cell line LNCaP. While in C42B, Nestin was expressed only in the adherent cells (Fig 8a). Embryonic stem cell marker such as Sca-1 are used to enrich properties such as, replication quiescence, androgen independence, multilineage differentiation and is capable of promoting regenerative capacity of prostate; in short characteristics of stem cells. In consistent with recent reports (32) our study indicated LNCaP cells grown in anchorage independent conditions showed increase in expression of Sca-1 (Figure 8c). Similarly Oct-4 responsible for stem cell self-renewal (33, 34) showed increase expression in C42B prostasphere (figure 8d). NSE is one of the prognostic indicators of aggressive androgen-independent prostate disease. Neuroendocrine cells provide growth and survival signals to surrounding tumour cells and thereby results in an increase in stem cell population (35, 38, 39). Gene expression is significantly increased in LNCaP prostasphere (Figue 8i). This maybe due to acquisition of the neuroendocrine characteristics by LNCaP in response to long-term androgen ablation therapy (35) or the selective differentiation of prostate cancer stem cells into neuroendcrine cells by non-adherent culture. A recent paper (10) investigated the role of WNT on the size and the self renewal capacity of the prostasphere. The authors noted a significant increase of keratin 18 and CD44 expression with the addition of Wnt3a. This increase in expression was detected in adherent and non adherent cultures with LNCaP prostasphere exhibiting slightly higher level than C42B. CD44 is an important marker with a distinct role in migration and signalling and is present in both stem and differentiating cell population. Evidences have been provided that show CD44 to be present in tumourââ¬âinitiating cells (36, 37). Therefore it is probable the CD44 would exhibit high exp
Wednesday, November 13, 2019
Essays --
After the abolition of slavery, many African Americans became extremely optimistic about their future in the United States. They figured there would be more equality, more opportunities, and overall more respect. They were given empty promises, false hopes, and sugar-coated lies, because, in all actuality, it was the exact opposite of what they imagined. Racism became even more prevalent, and it was just as hard, if not harder for African Americans. The abolition of slavery did not mean blacks were free. It did not mean we were equal. All it meant was that they had different ways to do the same thing, and they made sure that regardless of the freedom of slaves, African Americans would still be controlled in some way. On January 1, 1863, Abraham Lincoln freed the slaves. The Emancipation Proclamation was issued as the country entered the third year of the Civil War. It declared that ââ¬Å"all persons held as slaves â⬠¦ shall be then, thenceforward, and forever free.â⬠The Emancipation Proclamation was, and continues to be a symbol of equality and social justice. As a result, he was assassinated. After his death, Andrew Jackson became President of the United States. Jackson was an extreme racist, and made this very clear during his term of presidency. On July 9, 1886, the 14th Amendment was put into place. This law recognizes anyone born in the United States of America as a legal US citizen. It also forbids states from denying any person his life, liberty or property, without the correct means of the law. It was meant to protect the civil rights of all Americans regardless of their race or gender. The Fifteenth Amendment was established on February 26, 1869. It was the third in the Reconstruction Amendments. This amendment prohibits an... ...the Reconstruction, is that no matter what legally was done in an effort to help, there were always loopholes and other laws that would counter us from being totally free. We may not have been in slavery, but we were still enslaved, not only because of our mindsets, but because of our surroundings. The system was meant for us to fail, be dependent, and continue being submissive to the white man because no matter what laws were passed, or what changes were made, that is where they wanted us to be. Black codes, Jim Crow laws, segregation, and everything else that was legal after slavery was abolished, were all forms of slavery in a subtle way. They were meant to get in the heads of the blacks, and if you can get in a personââ¬â¢s head, you can control them. The reconstruction era was the beginning of a downward spiral between blacks and whites that branched after slavery.
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