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31.
WHO has targeted yaws for global eradication by 2020. The program goals are to interrupt the transmission in countries where yaws is endemic and to certify countries as yaws free where yaws was endemic in the past. No new rapid plasmin reagin (RPR) seroreactivity in young children is required for certification of elimination at a country level. We sought to evaluate whether antibody responses to specific treponemal antigens measured in a high-throughput multiplex bead array (MBA) assay differentiate past versus current infection and whether a nontreponemal lipoidal antigen test can be incorporated into the MBA. Serum and dried blood spot specimens collected for yaws surveillance projects in Ghana, Vanuatu, and Papua New Guinea (PNG) were run on MBA to measure antibodies against recombinant p17 (rp17) and treponemal membrane protein A (TmpA) treponemal antigens. Results were compared to standard treponemal laboratory (TPPA or TPHA [TPP(H)A]) and quantitative RPR test data. Of 589 specimens, 241 were TPP(H)A+/RPR+, 88 were TPP(H)A+/RPR, 6 were TPP(H)A/RPR+, and 254 were negative for both tests. Compared to TPP(H)A, reactive concordance of rp17 was 93.7%, while reactive concordance of TmpA was only 81.9%. TmpA-specific reactivity showed good correlation with RPR titers (R2 = 0.41; P < 0.0001). IgG responses to the lipoidal antigen used in RPR testing (cardiolipin) were not detected in the MBA. Our results suggest that TmpA can be used as a treponemal antigen marker for recent or active infection and potentially replace RPR in a high-throughput multiplex tool for large-scale yaws surveillance.  相似文献   
32.
Genetically, bipolar disorder is a complex genetic illness, in which both genes and environmental factors play an important role in pathogenesis. Linkage studies have reported suggestive evidence for genomic regions, especially on chromosome 18, but in most cases they have been inconclusive. A total of 12 pedigrees, from the islands of Majorca and Minorca (Balearic Archipelago), with a high expression of mental illness, have been studied. A scan of 29 polymorphic short tandem repeat markers was performed, spanning chromosomes 17 and 18 for bipolar and other affective disorder susceptibility loci. Narrow (only bipolar I disorder) and broad (bipolar plus other affective disorders) diagnosis criteria were employed. The loci D18S63, D18S452, D18S53, D18S61, D18S1161 and D17S831 showed LOD score values of less than -2. Thus, the positive linkage found by other authors on the regions 18p11.2 and 18p11.3 has not been reproduced in the families studied. The data obtained in chromosome 17 suggested two possible regions that could contain a bipolar disorder susceptibility gene: 17q11 (D17S1857, D17S798) and especially 17q24-qter (D17S949, D17S928). The maximum significant linkage was to D17S949 (17q24), following a recessive mode of inheritance. We have also found a positive LOD score value for D18S478 marker located in the region 18q12.  相似文献   
33.
Management of adnexal masses during pregnancy is challenging for most gynecologists. When surgery is needed, a minimally invasive approach should be preferred. The aim of this study was to evaluate the safety and feasibility of the closed entry technique for laparoscopic management of adnexal masses during pregnancy. We reviewed clinical records and videos of laparoscopic procedures performed during pregnancy. Seventeen pregnant patients with diagnosis of adnexal mass that required surgery underwent laparoscopic surgery using the closed entry or Veress technique. We searched for complications related to surgery and obstetrical and perinatal outcomes. Median gestational age at the moment of surgery was 17 weeks (range, 6–30+4 weeks). A total of 18 interventions were performed: 12 salpingo-oophorectomies, 3 cystectomies, 1 salpingectomy, and 2 ovarian detorsions. There were no major operative or entry-related complications. Median hospital stay was 2 days (range, 1–5). Perinatal outcomes were as follows: four preterm births (all of them induced), nine full-term deliveries, one early pregnancy loss at 7 weeks, one miscarriage at 18 weeks, and two ongoing uncomplicated pregnancies. Laparoscopic approach using closed entry technique with an individual selection of the puncture site is safe in the management of adnexal masses that require surgery during pregnancy. In our experience, the Veress technique is more versatile as it gives the surgeon more freedom to choose the location of the first trocar in patients with important space limitations due to the size of the adnexal mass and/or the enlarged gravid uterus.  相似文献   
34.
Prochlorococcus is a marine cyanobacterium responsible for a significant part of global primary production as well as being one of the most abundant organisms on Earth. Protein turnover is an essential and poorly understood aspect of the cyanobacterial response to environmental stresses. In the present work, cultures of the SS120 and MIT9313 strains were subjected to several conditions, and quantitative real time RT-PCR was used to measure changes in the expression of genes encoding three representative ATP-dependent proteases. We found common responses to conditions such as aging. However, the expression pattern under nutrient starvation was strikingly different in the two strains, probably reflecting the different regulatory backgrounds of the two ecotypes here studied.  相似文献   
35.
36.
BACKGROUND: A number of adhesion molecules are involved in the process of neutrophil infiltration into the lung. P-selectin is one of these neutrophil-endothelial cell adhesion molecules. A study was undertaken to examine the involvement of P-selectin in the development of bleomycin induced inflammation and the ability of N-acetyl-L-cysteine to reduce the potential expression of this selectin in rats. METHODS: N-acetyl-L-cysteine (3 mmol/kg po) was administered daily for seven days prior to bleomycin administration (2.5 U/kg). The kinetics of P-selectin expression and the effect of N-acetyl-L-cysteine after bleomycin treatment were measured using radiolabelled antibodies. P-selectin localisation was evaluated by immunohistochemistry and neutrophil infiltration was assessed by myeloperoxidase activity. RESULTS: Bleomycin administration resulted in an upregulation of P-selectin at 1 hour, returning to baseline at 3 hours. Myeloperoxidase activity showed a significant increase at 6 hours after bleomycin administration that lasted for 3 days. N-acetyl-L-cysteine treatment completely prevented these increases. CONCLUSION: Upregulation of P-selectin in the lung is associated with neutrophil recruitment in response to bleomycin. The beneficial effect of N-acetyl-L-cysteine on bleomycin induced lung injury may be explained in part by the prevention of neutrophil recruitment in the inflammatory stage of the disease.  相似文献   
37.
38.
Casanovas O  Hager JH  Chun MG  Hanahan D 《Oncogene》2005,24(44):6597-6604
Here, we describe the surprising residual capability of the Rb pathway to negatively regulate proliferation and tumorigenesis in a SV40 large T antigen (Tag)-driven mouse model of pancreatic islet carcinogenesis. Heterogeneous Tag expression during all progression stages suggested that a threshold level of the T antigen oncoprotein might be deterministic for beta-cell hyperproliferation and led us to hypothesize that Tag might not be fully inhibiting the tumor suppressor activity of Rb. Moreover, genomic profiling of these tumors by array CGH pointed to regions of loss on chromosomes 6 and 14, where the Rb pathway inhibitor p27 and Rb itself, respectively, reside. Indeed, genetic ablation of the p27(Kip1) or Rb genes accentuated Tag-induced tumorigenesis, with loss of Rb in particular broadly enhancing multiple parameters of tumorigenesis including the frequency and growth rates of premalignant lesions, of nascent solid tumors, and of invasive carcinomas. The data indicate that attenuation rather than complete inactivation of Rb tumor suppressor gene function, in the context of p53 inhibition, is sufficient to initiate tumorigenesis in this model of islet cell cancer, with the demonstrable possibility that subsequent losses of Rb or its regulators can enhance malignant progression. The results may be relevant to human papillomavirus (HPV)-induced cervical neoplasias where E7 oncogene expression levels or activity (in the case of intermediate/low-risk HPV subtypes) incompletely inhibits Rb tumor suppressor functions, as well as to other neoplasias where initiating oncogenic or tumor suppressor events reduce but do not abrogate Rb function.  相似文献   
39.
Function-blocking antibodies to VEGF receptors R1 and R2 were used to probe their roles in controlling angiogenesis in a mouse model of pancreatic islet carcinogenesis. Inhibition of VEGFR2 but not VEGFR1 markedly disrupted angiogenic switching, persistent angiogenesis, and initial tumor growth. In late-stage tumors, phenotypic resistance to VEGFR2 blockade emerged, as tumors regrew during treatment after an initial period of growth suppression. This resistance to VEGF blockade involves reactivation of tumor angiogenesis, independent of VEGF and associated with hypoxia-mediated induction of other proangiogenic factors, including members of the FGF family. These other proangiogenic signals are functionally implicated in the revascularization and regrowth of tumors in the evasion phase, as FGF blockade impairs progression in the face of VEGF inhibition.  相似文献   
40.
Accumulating evidence suggests that HIV-infected individuals have an increased risk of cardiovascular events. This risk seems to be at least partially mediated by dyslipidaemia, which is related to the use of highly active antiretroviral therapy (HAART). As HIV-infected individuals live longer due to HAART, their cardiovascular risk will invariably increase. Because HAART is likely to be used indefinitely, HAART-related dyslipidaemia has emerged as a major cardiovascular concern. This article summarises the evaluation of dyslipidaemia and cardiovascular risk in HIV-infected individuals, the potential pathophysiological and genetic mechanisms involved in HAART-related dyslipidaemia and the current treatment approaches. In general, dyslipidaemia is evaluated and treated as in HIV-negative persons. The first step is cardiovascular risk assessment and the determination of target lipid levels. A healthier lifestyle and, in particular, smoking cessation should be promoted. Lowering levels of low-density lipoprotein cholesterol (or, in the setting of significant hypertriglyceridaemia, non-high-density lipoprotein cholesterol) is the primary target of intervention. Switching HAART to a more lipid-favourable regimen should be considered if this does not jeopardise virological control. Many patients will need lipid-lowering drug therapy. Appropriate low-density lipoprotein cholesterol target levels may be more difficult to reach than in the HIV-negative population, and the potential for drug interactions when using lipid-lowering agents together with HAART needs to be considered. The identification of HAART strategies with no or minimal metabolic toxicity, and the identification of the safest and most efficacious lipid-lowering therapies for HIV-infected individuals with dyslipidaemia are important research goals.  相似文献   
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