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21.
22.
Loss of imprinting of IGF2 and H19 in osteosarcoma is accompanied by reciprocal methylation changes of a CTCF-binding site 总被引:10,自引:0,他引:10
Ulaner GA Vu TH Li T Hu JF Yao XM Yang Y Gorlick R Meyers P Healey J Ladanyi M Hoffman AR 《Human molecular genetics》2003,12(5):535-549
The adjacent insulin-like growth factor 2 (IGF2) and H19 genes are imprinted in most normal human tissues, but imprinting is often lost in tumors. The mechanisms involved in maintenance of imprinting (MOI) and loss of imprinting (LOI) are unresolved. We show here that osteosarcoma (OS) tumors with IGF2/H19 MOI exhibit allele-specific differential methylation of a CTCF-binding site upstream of H19. LOI of IGF2 or H19 in OS occurs in a mutually exclusive manner, and occurs with monoallelic expression of the other gene. Bisulfite sequencing reveals IGF2 LOI occurs with biallelic CpG methylation of the CTCF-binding site, while H19 LOI occurs with biallelic hypomethylation of this site. Our data demonstrate that IGF2 LOI and H19 LOI are accompanied by reciprocal methylation changes at a critical CTCF-binding site. We propose a model in which incomplete gain or loss of methylation at this CTCF-binding site during tumorigenesis explains the complex and often conflicting expression patterns of IGF2 and H19 in tumors. 相似文献
23.
Nguyen Tuyen Trat Tiffany Tieu Ngoc Thanh Vu Linda Sokal-Gutierrez Karen 《Maternal and child health journal》2022,26(9):1811-1819
Maternal and Child Health Journal - Vietnam’s post-war globalization, economic development, and urbanization have contributed to a nutrition transition from traditional diets to... 相似文献
24.
Emmanuel Nwachuku Yizhi Shan Prabhu Senthil-Kumar Todd Braun Ryan Shadis Orlando kirton Thai Q. Vu 《American journal of surgery》2021,221(1):240-242
BackgroundClostridioides difficile infection (CDI) is traditionally taught to be an antibiotic associated diarrheal infection. This diagnosis is based on the presence of clinical symptoms (usually defined as more than 3 watery, loose or unformed stool within 24 h) coupled with a diagnostic test. There is now a new presentation of CDI, including progression to toxic megacolon, in patients without diarrhea.MethodsWe report a case series of 9 surgical patients from a single institution who developed CDI without preceding diarrhea.ResultAll 9 patients had CDI with positive laboratory testing for C. difficile toxin. They, however, presented with a lack of or minimal bowel movements. Six patients had rapid development of abdominal distention, 1 patient had a single episode of watery stool in 3 days, while the other 2 patients presented with constipation. Seven patients received stool softeners, suppositories and/or enemas for presumed constipation. Four patients had a mild course of infection and were successfully treated medically. The other 5 patients developed toxic megacolon, and eventually required total abdominal colectomy. Out of the 5 patients that required total colectomy, 2 expired.ConclusionCDI must be suspected in patients who rapidly develop abdominal distention, vague abdominal complaints or change in bowel function even in the absence of diarrhea, especially if coupled with multi-system organ failure. 相似文献
25.
26.
Nguyen Minh Hai Nguyen Dang Dung Dinh Cong Pho Vu Tung Son Vu Ngoc Hoan Phan Tan Dan Bui Dang The Anh La Huong Giang Pham Ngoc Hung 《Vaccine》2021,39(7):1140-1147
BackgroundROTAVAC® is derived from human 116E rotavirus (RV) neonatal strain. In this study, we evaluated the immunogenicity, safety and reactogenicity of ROTAVAC® in Vietnam.MethodWe conducted a phase IV clinical trial in healthy infants aged 6–8 weeks using the complete regimen of ROTAVAC® with three doses. Serum anti-RV IgA was measured by enzyme-linked immunosorbent assay to assess the geometric mean concentration in infants who received the complete regimen of the vaccine.ResultsA total of 360 participants were enrolled in this clinical trial. The mean age ± standard deviation at enrollment was 6.9 ± 0.6 weeks. The anti-RV IgA titer was 4.01 ± 3.74 mg/ml pre-vaccination and substantially increased to 29.27 ± 80.64 mg/ml post-vaccination. The value of logIgA significantly increased (p = 0.003) from 0.28 ± 0.79 to 1.03 ± 0.54. The proportion of participants with equal to and greater than 3-fold and 4-fold shifts in pre- to post-vaccination antibody titer (IgA) were 55.4% and 48.3%, respectively. No adverse events or serious adverse events were recorded immediately within 30 min after the administration of each dose. The most common adverse events within 14 days after each visit were fever, unusual crying and irritability. Other adverse events occurred at a low rate, and no case of intussusception was noted.ConclusionsThe complete regimen of ROTAVAC® demonstrated an immunological response with clinically acceptable safety profile. Post-completion of this study, ROTAVAC® is now a WHO-prequalified vaccine and available in Vietnam. 相似文献
27.
Nelson L. Rhodus Bin Cheng Sandra Myers Walter Bowles Vu Ho Frank Ondrey 《Clinical immunology (Orlando, Fla.)》2005,114(3):278
To explore the feasibility of detection of the level of NF-κB-dependent cytokines in oral fluids from patient with oral lichen planus (OLP) for clinical application, 13 OLP subjects were enrolled in the study as were 13 age–sex-matched controls. In each subject, the whole unstimulated saliva (WUS), mixture of saliva and isotonic saline oral rinse (Saliva-NaCl), and lesion tissue transudates (TT) were collected by standard techniques. The level of cytokines, TNF-alpha, IL-1-alpha, IL-6, and IL-8 in three types of oral fluids was determined by ELISA. In the three types of oral fluids, a significantly higher level of these cytokines was detected in OLP patients than in normal controls. These results indicate that NF-κB-dependent inflammatory cytokines may be detected at increased levels in certain oral fluids which may have diagnostic and prognostic potential for monitoring disease activity and making therapeutic decisions in patients with OLP. 相似文献
28.
Vu Thuy Khanh Le-Trilling Jana-Fabienne Ebel Franziska Baier Kerstin Wohlgemuth Kai Robin Pfeifer Aart Mookhoek Philippe Krebs Madita Determann Benjamin Katschinski Alexandra Adamczyk Erik Lange Robert Klopfleisch Christian M. Lange Viktoriya Sokolova Mirko Trilling Astrid M. Westendorf 《European journal of immunology》2023,53(2):2249940
Primary and recurrent cytomegalovirus (CMV) infections frequently cause CMV colitis in immunocompromised as well as inflammatory bowel disease (IBD) patients. Additionally, colitis occasionally occurs upon primary CMV infection in patients who are apparently immunocompetent. In both cases, the underlying pathophysiologic mechanisms are largely elusive - in part due to the lack of adequate access to specimens. We employed the mouse cytomegalovirus (MCMV) model to assess the association between CMV and colitis. During acute primary MCMV infection of immunocompetent mice, the gut microbial composition was affected as manifested by an altered ratio of the Firmicutes to Bacteroidetes phyla. Interestingly, these microbial changes coincided with high-titer MCMV replication in the colon, crypt hyperplasia, increased colonic pro-inflammatory cytokine levels, and a transient increase in the expression of the antimicrobial protein Regenerating islet-derived protein 3 gamma (Reg3γ). Further analyses revealed that murine and human intestinal epithelial cell lines, as well as primary intestinal crypt cells and organoids represent direct targets of CMV infection causing increased cell death. Accordingly, in vivo MCMV infection disrupted the intestinal epithelial barrier and increased apoptosis of intestinal epithelial cells. In summary, our data show that CMV transiently induces colitis in immunocompetent hosts by altering the intestinal homeostasis. 相似文献
29.
Conclusion Malgré des défaillances occasionnelles, les observations détaillées de l'ensemble des 45 cas permettent de dire qu'il n'y a pas de relation entre les départs et la fréquence des consommations d'héoÏne antérieures au départ, telle que le montrent les analyses chimiques.Les 45 départs sont-ils des échecs? Si 1'on prend comme critères de réussite l'indépendance d'un individu par rapport à la drogue, son indépendance affective et son indépendance économique, l'absence de la relation précédente suggère qu'un certain nombre d'entre eux pourrait bien etre sorti de la dependance de la drogue au moment de leur départ, pour autant qu'ils puissent satisfaire par la suite leurs besoins économique et affectif. Le nombre d' échecs tendrait ainsi à diminuer.Sur le plan opposé, les 25 cas ayant franchi toutes les phases du programme de cure sont-ils des réussites? La difficulté de les suivre régulièrement sur une longe période incite à la réserve. Le chiffre de 36% est relativement optimiste. Ces résultats tempèrent les conclusions énoncées dans le rapport Schmidt et Delachaux (2) mais lui apportent en mÊme temps une base de justification plus solide.
Non medical treatment of heroÏn addicts and chemical analysis as an element of appreciation
Summary Group psychotherapy programme is applied in a heroÏn addiction treatment center in conjunction with a systematic planning of chemical analyses along the course of the cure. The addicts live under inspected regime. At best 25 out of 70 cases (36 %) conclude the programme with occasional and non repetitive failures. The question of their follow-up beyond their treatment period arises in order to better evaluate their retrieval.No relationship was observed between individuals who had quit the programme and the frequency of heroÏn consumptions during the time they were under treatment.
Nichtmedizinische Behandlung von Heroinomanen und chemische Analyse als Bewertungselement
Zusammenfassung In einer Anstalt zur Behandlung der Heroinsucht wurde ein gruppenpsychotherapeutisches Programm zusammen mit einer systematischen Plannung chemischer Analysen während der Behandlung durchgeführt. Die Süchtigen leben unter Uberwachung. Höchstens 25 aus 70 Fällen (36%) schlossen das Programm mit gelegentlichen und nichtwiederholten Rückfällen ab. Ihre Uberwachung nach der Behandlungsperiode als Bewertungselement ihrer Rehabilitation bleibt noch offen. Ein Zusammenhang zwischen den vom Programm abtretenden Personen und der Häufigkeit ihres Heroinverbrauches während der Behandlungsperiode konnte nicht festgestellt werden.相似文献
30.
Compromised kidney graft rejection response in Vervet monkeys after withdrawal of immunosuppressants tacrolimus and sirolimus 总被引:2,自引:0,他引:2
Chen H Peng J Luo H Loubeau M Wan X Xu D Qi S Vu MD Daloze P Fitzsimmons WE Bekersky I Peets J Sehgal SN Wu J 《Transplantation》2000,69(8):1555-1561
BACKGROUND: In nonprimates, organ allografts are often not rejected after withdrawal of immunosuppression. In this study, we examined whether such a phenomenon also occurs in primates. METHODS: Vervet monkeys were transplanted with renal allografts and treated for 60 days with tacrolimus, or tacrolimus plus sirolimus. The drugs were totally withdrawn on day 61. The survival of the monkeys was monitored, and their response to donor- or third party-derived alloantigens was examined in vivo and in vitro. RESULTS: The majority (80-100%) of the grafts survived for at least additional 30 days with no signs of acute rejection. The compromised rejection is donor-specific, because recipient monkeys failed to reject a donor-derived skin graft, but a third-party skin graft was rejected. In vitro mixed lymphocyte reaction and interleukin-2 production in the mixed lymphocyte reaction between the recipients and their donors or between the recipients and a third party had no discernable patterns, and thus did not reflect the in vivo status of the immune system. Although the recipients could not reject the graft acutely after drug withdrawal, the kidney grafts and the donor-derived skin grafts had pathological findings of chronic rejection. CONCLUSIONS: The rejection response of the monkeys to an established graft after withdrawal of immunosuppression is compromised. The compromised rejection is specific and is not due to a permanent alteration of the immune system by the initial drug treatment. The allografts are not inert but have low levels of interaction with the recipient immune system. 相似文献