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21.
Cyclin B and E2F-1 expression in prostate carcinoma cells treated with the novel retinoid CD437 are regulated by the ubiquitin-mediated pathway 总被引:10,自引:0,他引:10
Farhana L Dawson M Rishi AK Zhang Y Van Buren E Trivedi C Reichert U Fang G Kirschner MW Fontana JA 《Cancer research》2002,62(13):3842-3849
E2F-1 and cyclin B are important regulators of the cell cycle, and their expressionand degradation are tightly regulated. Proteolysis of both molecules is mediated by the ubiquitin degradation pathway involving the activation of specific E3 ubiquitin ligases. Treatment of prostate carcinoma cells with the novel retinoid 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalene carboxylic acid (CD437/AHPN) results in the enhanced expression of E2F-1 and rapid degradation of cyclin B in the absence of the modulation of mRNA levels; this is accompanied by the S phase arrest of the cells and subsequent apoptosis. The elevated level of E2F-1 is because of the enhanced stability of the molecule, as indicated by pulse-labeling studies, demonstrating a prolonged half-life. The enhanced E2F-1 stability is associated with the concomitant acetylation of E2F-1, the disassociation of E2F-1 from the E2F-1 E3 ligase p45(SKP2), and decreased E2F-1 ubiquitination, suggesting CD437 inhibition of E-3 E2F-1 ligase activity. Exposure of the cells to CD437 also results in the enhanced association of the cyclin B E3 ligase APC with cyclin B and the rapid proteolysis of cyclin B. The CD437-enhanced proteolysis of cyclin B is blocked in the presence of the ubiquitin proteolysis inhibitor N-acetyl-leu-leu-norleu-al. Thus, CD437 modulates the expression of E2F-1 and cyclin B through the simultaneous stimulation and inhibition of the cyclin B and E2F-1 E3 ligases, respectively. 相似文献
22.
Although global and national strategies to promote a human rights-based approach to HIV/AIDS have been in place for many years, these strategies appear to have had little impact at the local level, where human rights violations are commonplace. In this article, Peris Jones and Farhana Zuberi summarize findings from a recently completed research project, the Tswelopele study, in South Africa. The study documented human rights violations in three areas: privacy and disclosure; informed consent and HIV testing; and access to health-care services. The article describes these violations and explores why discrimination still occurs at the local level. The authors conclude that remedial action is required, targeting the persons and institutions that shape attitudes and beliefs, including churches, workplaces, schools, and the media; and that this action needs to be complemented by wider public education, activism at hospitals and in the courts and, more generally, fulfillment of socio-economic rights. 相似文献
23.
Enteric campylobacter: purging its secrets? 总被引:4,自引:0,他引:4
Campylobacterial infections are the most common cause of bacterial enterocolitis in humans. Among children, especially in developing countries, Campylobacter infections can cause severe life-threatening diarrheal disease. Although usually associated with a benign outcome in the developed world, the burden of illness posed by Campylobacter infections is enormous, and serious neurologic sequelae also can occur. For a variety of reasons our understanding of the molecular and cellular pathogenesis of Campylobacter infection has lagged far behind that of other enteric pathogens. However, recent completion of the genome sequence of Campylobacter jejuni promises to open up the Campylobacter research field with the prospect of developing novel therapeutic and preventive strategies. 相似文献
24.
We used contingent valuation technique to estimate the parental willingness to pay for an episode of diarrhoea among 324 children
of both sexes aged between five and seven years in two rural villages of Chennai in India. The aim was to examine if there
was any gender bias in the parental willingness to treat children for a diarrhoeal episode, and if so to what extent. The
willingness to pay was specified as a hedonic function of the duration and severity of an episode, and of parents' socioeconomic
characteristics. The findings suggest that parents were willing to pay more to protect their male child compared to the female
child suffering from a diarrhoeal episode. The median willingness to pay to avoid an episode for male and female children
were calculated at Rs. 33.7 (approx. US0.72) and Rs. 25.2 (approx. US 0.72) and Rs. 25.2 (approx. US 0.54) respectively – a difference of around 34%.
After adjusting for the greater duration and severity of the illness, it was found that the difference between the two medians
increased to 51%. 相似文献
25.
Nephrogenic fibrosing dermopathy: two pediatric cases 总被引:7,自引:0,他引:7
Jan F Segal JM Dyer J LeBoit P Siegfried E Frieden IJ 《The Journal of pediatrics》2003,143(5):678-681
We report two pediatric cases of nephrogenic fibrosing dermopathy (NFD), first described in 2000. NFD is a condition in which individuals with renal dysfunction have development of extensive skin hardening and histopathologic evidence of a scleromyxedema-like condition. 相似文献
26.
Salmonella enterica Serovar Typhi-Specific Immunoglobulin A Antibody Responses in Plasma and Antibody in Lymphocyte Supernatant Specimens in Bangladeshi Patients with Suspected Typhoid Fever 下载免费PDF全文
Alaullah Sheikh M. Saruar Bhuiyan Farhana Khanam Fahima Chowdhury Amit Saha Dilruba Ahmed K. M. A. Jamil Regina C. LaRocque Jason B. Harris Mian Mashhud Ahmad Richelle Charles W. Abdullah Brooks Stephen B. Calderwood Alejandro Cravioto Edward T. Ryan Firdausi Qadri 《Clinical and Vaccine Immunology : CVI》2009,16(11):1587-1594
Many currently available diagnostic tests for typhoid fever lack sensitivity and/or specificity, especially in areas of the world where the disease is endemic. In order to identify a diagnostic test that better correlates with typhoid fever, we evaluated immune responses to Salmonella enterica serovar Typhi (serovar Typhi) in individuals with suspected typhoid fever in Dhaka, Bangladesh. We enrolled 112 individuals with suspected typhoid fever, cultured day 0 blood for serovar Typhi organisms, and performed Widal assays on days 0, 5, and 20. We harvested peripheral blood lymphocytes and analyzed antibody levels in supernatants collected on days 0, 5, and 20 (using an antibody-in-lymphocyte-supernatant [ALS] assay), as well as in plasma on these days. We measured ALS reactivity to a serovar Typhi membrane preparation (MP), a formalin-inactivated whole-cell preparation, and serovar Typhi lipopolysaccharide. We measured responses in healthy Bangladeshi, as well as in Bangladeshi febrile patients with confirmed dengue fever or leptospirosis. We categorized suspected typhoid fever individuals into different groups (groups I to V) based on blood culture results, Widal titer, and clinical features. Responses to MP antigen in the immunoglobulin A isotype were detectable at the time of presentation in the plasma of 81% of patients. The ALS assay, however, tested positive in all patients with documented or highly suspicious typhoid, suggesting that such a response could be the basis of improved diagnostic point-of-care-assay for serovar Typhi infection. It can be important for use in epidemiological studies, as well as in difficult cases involving fevers of unknown origin.Salmonella enterica serovar Typhi (serovar Typhi) is the cause of typhoid fever, an illness that affects over 20,000,000 individuals worldwide each year, killing over 200,000 (5, 8, 16). The largest burden of typhoid fever is borne by impoverished individuals in resource-poor areas of the world. Serovar Typhi is a human-restricted invasive enteric pathogen which, after ingestion, crosses the intestinal mucosa, is taken up by gut-associated lymphoreticular tissues, and enters the systemic circulation. Both mucosal and systemic host immune responses are stimulated after infection. Serovar Typhi is an intracellular pathogen, and antibody and cell-mediated immune responses occur after infection or immunization with live oral attenuated typhoid vaccines (10, 25, 34).Diagnostic tests for typhoid fever often lack sensitivity and/or specificity, especially in areas of the world that are endemic for typhoid fever, where clinically distinguishing typhoid fever from other febrile illnesses is difficult (5, 17, 39). Microbiologic culturing of blood is approximately 30 to 70% sensitive, with the highest sensitivity being associated with an absence of prior use of antibiotics and the culturing of larger volumes of blood, features that complicate this mode of diagnosis in young children (5, 6, 8, 36). Microbiologic culturing of bone marrow aspirates is more sensitive than blood but often clinically impractical (1, 11, 12). Serum Widal assay titers are often nonspecific in endemic settings and are of limited value unless titers are markedly elevated or are analyzed for changes from acute to convalescent phases of illness (18, 33, 38). Molecular diagnostic assays including PCR are promising, but issues of practicality, contamination, and quality control have limited their use in many resource-poor areas of the world (14).Since serovar Typhi interacts with both the mucosal and the systemic immune systems, we were interested to determine whether analyses of mucosal immune responses would give improved insight into this human-restricted infection. Activated mucosal lymphocytes migrate from intestinal tissue and circulate within peripheral blood before rehoming to mucosal tissues (20, 31). This migration peaks 1 to 2 weeks after intestinal infection and may be measured by using peripheral blood mononuclear cells (PBMC) in an antibody-secreting cell (ASC) assay (19, 26) or in supernatants recovered from harvested PBMC (the “antibody in lymphocyte supernatant” [ALS] assay) (7, 31). Although ALS and ASC responses have previously been measured after immunization with oral live attenuated typhoid vaccines, detailed analyses of ALS or ASC responses in individuals with wild-type typhoid fever are lacking (21, 24). In order to gain further insight into mucosal immune responses during wild-type serovar Typhi infection, we undertook a study to characterize the serum and ALS responses to serovar Typhi among individuals with suspected typhoid fever in Bangladesh. 相似文献
27.
Megumi Ohishi Fumiko Harada Farhana Rahman Isao Saito Yoshiro Kawano Kayoko Nozawa‐Inoue Takeyasu Maeda 《Anatomical record (Hoboken, N.J. : 2007)》2009,292(8):1185-1191
The terminal Schwann cells (TSCs) which play crucial roles in regeneration of the periodontal Ruffini endings (RE) exhibit immunoreaction for glial cell line‐derived neurotrophic factor (GDNF). However, no information is available regarding the role of GDNF in the periodontal RE during nerve regeneration. This study was undertaken to examine the changes in GDNF expression in the rat periodontal RE following transection of the inferior alveolar nerve (IAN) using immunohistochemistry for GDNF and S‐100 protein, a marker for the TSCs. We additionally investigated the changes in expression of GDNF in the trigeminal ganglion (TG) at protein and mRNA levels. A transection to IAN induced a disappearance of the TSCs from the alveolus‐related part (ARP), followed by a migration of spindle‐shaped cells with S‐100 but without GDNF immunoreactions into the tooth‐related part (TRP) by postoperative (PO) week 2. At PO week 2, GDNF immunoreacted cellular elements increased in number in the ARP although the spindle‐shaped cells without GDNF reaction remained in the TRP. After PO week 4, many GDNF‐positive TSCs appeared in the ARP though the spindle‐shaped cells vanished from the TRP. A real time RT‐PCR analysis demonstrated the highest elevation of GDNF mRNA in the TG at PO week 2. These findings suggested the involvement of this molecule in the maturation and maintenance of the periodontal RE during regeneration. Taken together with our previous and current studies, it appears that the regeneration of the periodontal RE is controlled by multiple neurotrophins in a stage‐specific manner. Anat Rec, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
28.
Abbas Bhuiya SMA Hanifi Farhana Urni Shehrin Shaila Mahmood 《International journal for equity in health》2009,8(1):29-11
Background
Achieving equity by way of improving the condition of the economically poor or otherwise disadvantaged is among the core goals of contemporary development paradigm. This places importance on monitoring outcome indicators among the poor. National surveys allow disaggregation of outcomes by socioeconomic status at national level and do not have statistical adequacy to provide estimates for lower level administrative units. This limits the utility of these data for programme managers to know how well particular services are reaching the poor at the lowest level. Managers are thus left without a tool for monitoring results for the poor at lower levels. This paper demonstrates that with some extra efforts community and facility based data at the lower level can be used to monitor utilization of healthcare services by the poor.Methods
Data used in this paper came from two sources- Chakaria Health and Demographic Surveillance System (HDSS) of ICDDR,B and from a special study conducted during 2006 among patients attending the public and private health facilities in Chakaria, Bangladesh. The outcome variables included use of skilled attendants for delivery and use of facilities. Rate-ratio, rate-difference, concentration index, benefit incidence ratio, sequential sampling, and Lot Quality Assurance Sampling were used to assess how pro-poor is the use of skilled attendants for delivery and healthcare facilities.Findings
Poor are using skilled attendants for delivery far less than the better offs. Government health service facilities are used more than the private facilities by the poor. Benefit incidence analysis and sequential sampling techniques could assess the situation realistically which can be used for monitoring utilization of services by poor. The visual display of the findings makes both these methods attractive. LQAS, on the other hand, requires small fixed sample and always enables decision making.Conclusion
With some extra efforts monitoring of the utilization of healthcare services by the poor at the facilities can be done reliably. If monitored, the findings can guide the programme and facility managers to act in a timely fashion to improve the effectiveness of the programme in reaching the poor. 相似文献29.
30.
Leighton MP Nundlall S Starborg T Meadows RS Suleman F Knowles L Wagener R Thornton DJ Kadler KE Boot-Handford RP Briggs MD 《Human molecular genetics》2007,16(14):1728-1741
Disruption to endochondral ossification leads to delayed and irregular bone formation and can result in a heterogeneous group of genetic disorders known as the chondrodysplasias. One such disorder, multiple epiphyseal dysplasia (MED), is characterized by mild dwarfism and early-onset osteoarthritis and can result from mutations in the gene encoding matrilin-3 (MATN3). To determine the disease mechanisms that underpin the pathophysiology of MED we generated a murine model of epiphyseal dysplasia by knocking-in a matn3 mutation. Mice that are homozygous for the mutation develop a progressive dysplasia and have short-limbed dwarfism that is consistent in severity with the relevant human phenotype. Mutant matrilin-3 is retained within the rough endoplasmic reticulum of chondrocytes and is associated with an unfolded protein response. Eventually, there is reduced proliferation and spatially dysregulated apoptosis of chondrocytes in the cartilage growth plate, which is likely to be the cause of disrupted linear bone growth and the resulting short-limbed dwarfism in the mutant mice. 相似文献