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1.
Genetic and epigenetic alterations importantly contribute to the pathogenesis of lung cancer. In the study, we measured the frequency and distribution of molecular abnormalities of EGFR as well as the aberrant promoter methylations of BRCA1, MGMT, MLH1, and RASSF1A in Vietnamese lung adenocarcinomas. We investigated the association between genetic and epigenetic alteration, and between each abnormality with clinicopathologic parameters. Somatic EGFR mutation that was found in 49/139 (35.3%) lung adenocarcinomas showed a significant association with young age, female gender, and non-smokers. EGFR overexpression was identified in 82 tumors (59.0%) and statistical relationships with EGFR or BRCA1 methylation but not EGFR mutation. In addition, EGFR, BRCA1, MGMT, MLH1, and RASSF1A methylations were found in 33 (23.7%), 41 (29.5%), 46 (33.1%), 28 (20.1%), and 41 (29.5%) cases of a total of 139 lung adenocarcinomas, respectively. The RASSF1A methylation was found to be linked to the smoking habit. Methylations in MGMT and RASSF1A were also found to correlate with metastasis status. Furthermore, the distribution of EGFR mutation and that of BRCA1, MGMT or RASSF1A methylation were significantly exclusive in lung adenocarcinomas. The main finding of our study demonstrate that epigenetic abnormalities might play a critical role for the lung tumorigenesis in patients with smoking history and metastasis, and partly affect the predictive value of EGFR mutations through blocking expression due to promoter EGFR hypermethylation. Mutually exclusive distribution of genetic and epigenetic alterations reflects differently biological characteristics in the etiology of lung adenocarcinomas.  相似文献   
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The pulmonary manifestations of varicella are observed more frequently in adults than in children. They make present according to 3 modes: acute, subacute or chronic. The authors report 2 cases of chronic pulmonary manifestations in the form of diffuse, partially calcified micronodular lesions of both lung fields observed in the course of varicella in adults.  相似文献   
4.
Phacolytic glaucoma (PG) is usually caused by hypermature lens and the principal mechanism is the obstructed trabecular mesh-work with the leaky lens capsule proteins The incidence of PG in author’s hospital, where the backlog of cataract is relatively high, occupied ten percent of operated glaucoma and three percent of cataract surgeries. The PG in severe cases is commonly misdiagnosed with endophthalmitis and was therefore  相似文献   
5.
Repair and regeneration are mutually exclusive responses to injury. Previous studies have shown that wound fluids promote proliferation, but not differentiation, of myoblasts in vitro. This study explored the ability of the repair environment within polyvinyl alcohol sponges to support cellular events of skeletal muscle regeneration in vivo. Neonatal rat L8 myoblasts were modified to express beta-galactosidase then inoculated into plain sponges or sponges containing minced muscle. Labeled myoblasts were found in myotubes within minced muscle. In contrast, myoblasts inoculated into sponges lacking muscle remained mononucleate. Occurrence of labeled myoblasts within myotubes, which required fusion, represents differentiation of inoculated myoblasts to participate in regeneration. Failure of myoblasts to form myotubes in sponges lacking muscle suggests that this wound repair environment cannot support morphologic differentiation of myoblasts. Although this repair environment can support the survival of myoblasts, it did not support myogenesis, an event necessary to complete skeletal muscle regeneration. Data from this study reinforce earlier studies in vitro and suggest that the properties attributed to wound fluids are inherent in the wound environment. Whether the inability of this environment to support myogenesis is the consequence of the absence of essential factors or the presence of inhibitors remains to be determined.  相似文献   
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A freely moving pseudotumoral formation resembling a peeled "hard-boiled egg" was discovered in the abdominal cavity of an 82-year-old male patient during exploratory laparotomy for assessment of hepatocarcinoma in the left lobe of the liver. The formation involved a twisted epiploic fringe, which was necrotic, sclerotic, and calcified. The absence of any attachment and the avascular aspect of this pseudotumor suggest a possibly self-sustaining mechanism for the laminar sclerosis organized around the necrotic adipose tissue.  相似文献   
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The effects of interleukin-1 and were tested on the [3H]-arachidonic acid release and the prostaglandin synthesis by human cultured synovial cells and chondrocytes. Both forms of interleukin-1 stimulated the arachidonic acid release but interleukin-1 was more potent than IL-1. Human synovial cells and chondrocytes synthesized three types of prostaglandins upon stimulation with interleukin-1 or : prostaglandin E2, F2 and 6-keto-prostaglandin F1. Regarding the synthesis of these prostaglandins, IL-1 was again more potent than IL-1. A comparison between interleukin-1-stimulated synovial cells and chondrocytes revealed neither significant quantitative nor qualitative differences in both the arachidonic acid release and the prostaglandin synthesis.  相似文献   
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OBJECTIVES: In July 1997, the National Reference Center for Sexually Transmitted Diseases of Bangui, Central African Republic (CAR), was expanded by the creation of an anonymous and voluntary counseling and testing (VCT) unit for HIV infection, the Anonymous Surveillance Unit (Unité de Dépistage Anonyme [UDA]). The goal of the UDA was to initiate and promote voluntary HIV testing in the general adult population of Bangui. We carried out an observational and comprehensive survey over a 4-year period to document and analyze the experience of VCT in the UDA, with special attention to risk factors associated with HIV infection. METHODS: All clients for VCT were given adequate pretest counseling by trained counselors focused on knowledge about HIV infection and sexually transmitted infections, individual risks of acquiring HIV, and anticipation of the client's attitude about test results. After consent was obtained, a blood sample was drawn and tested for HIV by two ELISAs in parallel. The client paid a standard cost of $1.20 at the initial visit. After a week, test results were given to the client during the posttest visit, at which time HIV-seropositive individuals received emotional support and were referred to specific social or medical structures. Seronegative clients received reinforcement of prevention messages and were asked to come back for serologic follow-up free of charge after 3 (M3) and 12 (M12) months. RESULTS: From July 1997 to March 2001, 5686 individuals aged 14 to 65 years (mean age, 27 years) had an initial visit for VCT (V1). Peaks of UDA visitation (250-450 clients) were observed on the annual AIDS Day in the CAR, at which time HIV serologic testing was offered free of charge. A total of 5060 (89%) clients came back for a second visit (V2) to receive test results. Among those, 18.3% were infected with HIV type 1. Multivariate analysis of risk factors demonstrated marked association of HIV seropositivity with age, female gender, widowed/divorced women, poor or low education level, occupations such as civil servants or merchants, presence of symptoms of sexually transmitted infections, and lack of systematic condom use. Single young women were at higher risk for HIV infection compared with men of the same age (OR = 7.7 for women aged 15-24 years, 95% CI: 4.0-14.0; OR = 2.8 for women aged 25-34 years, 95% CI: 1.7-4.5). Widowed women older than 44 years of age were more likely to be HIV-seropositive than men (OR = 10.0; 95% CI: 1.7-83.6). A total of 885 (21%) HIV-seronegative individuals returned for follow-up at 3 months (M3; 0.45% rate of seroconversion). Seventy-nine (9%) individuals returned at 12 months (M12), without any new cases of HIV infection. HIV-negative clients consulting at M3 and M12 showed a significant reduction in unprotected intercourse with occasional sexual partners. CONCLUSION: This experience demonstrates that VCT for HIV infection is feasible in Central Africa.  相似文献   
9.
The pathways conferring immunity to human filariases are not well known, in part because human-pathogenic filariae do not complete a full life cycle in laboratory mice. We have used the only fully permissive infection of mice with filariae, i.e., infection of BALB/c mice with the rodent filarial nematode Litomosoides sigmodontis. Our previous results showed that worm development is inversely correlated with Th2 cytokine production and eosinophilia. The scope of the present study was to directly elucidate the role of interleukin-5 (IL-5) and eosinophils in controlling the development of L. sigmodontis after vaccination and in primary infection. BALB/c mice immunized with irradiated third-stage larvae (L3) were confirmed to have elevated IL-5 levels as well as high subcutaneous eosinophilia and to attack and reduce incoming larvae within the first 2 days, resulting in 70% reduction of worm load. Treatment of vaccinated mice with anti-IL-5 antibody (TRFK-5) suppressed both blood and tissue eosinophilia and completely abolished protection. This demonstrates, for the first time in a fully permissive filarial infection, that IL-5 is essential for protection induced by irradiated L3 larvae. In contrast, in primary-infected mice, anti-IL-5 treatment did not modify filarial infection within the 1st month, most likely because during primary infection IL-5-dependent mechanisms such as subcutaneous eosinophilia are induced too late to disturb worm establishment. However, there is a role for IL-5 late in primary infection where neutrophil-dependent worm encapsulation is also under the control of IL-5. Received: 30 March 2000  相似文献   
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