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61.
Among more than 200 human papillomavirus (HPV) types presumed to exist, 18 "high-risk" HPV types are frequently found in anogenital cancer. The best studied types are HPV-16 and 18, which are only distantly related to one another and form two separate phylogenetic branches, each including six closely related types. HPV-30, 53, 56, and 66 form a third phylogenetic branch unrelated to HPV-16 and 18. Worldwide comparison of HPV-16 and 18 isolates revealed a distribution of variant genomes that correlated with the geographic origin and the ethnicity of the infected cohort and led to the concept of unique African, European, Asian, and Native American HPV-16 and 18 variants. Here, we address the question whether similar phylogenies are found for HPV-53, 56, and 66 by determining the sequence of the long control regions (LCR) of these HPVs in samples from Europe, Asia, and Africa, and from immigrant societies in North and South America. Phylogenetic trees calculated from point mutations and a few insertions/deletions affecting 2-4.2% of the nucleotide sequences were distinct for each of the three HPVs and divergent from HPV-16 and 18. In contrast to the "star-phylogenies" formed by HPV-16 and 18 variants, 44 HPV-53 isolates represented nine variants, which formed two deep dichotomic branches reminiscent of the beginning split into two new taxa, as recently observed for subtypes of HPV-44 and 68. A total of 66 HPV-56 isolates represented 17 variants, which formed three branches preferentially containing European, Asian, and African variants. Variants of a fourth branch, deeply separated from the other three, were characterized by a 25 bp insertion and created a dichotomy rather than star-like phylogeny. As it contained isolates from cohorts in all continents, it may have evolved before the spread of humans into all continents. 18 of 31 HPV-66 isolates represented the prototype clone, which was found in all parts of the world, while the remaining 13 clones formed 11 branches without any geographic association. Our findings confirm the notion of a quantitatively limited genomic diversity of each HPV type with some correlation to the geographic origin of the sample. In addition, we observed in some variants of these three HPV types mutations that affect the amino acid sequence of the E6 oncoproteins and the L1 capsid protein, supporting the possibility of immunogenic and oncogenic diversity between variants of any HPV type.  相似文献   
62.
HIV cross-sectional studies were conducted among high-risk populations in 9 countries of South America. Enzyme-linked immunosorbent assay screening and Western blot confirmatory testing were performed, and env heteroduplex mobility assay genotyping and DNA sequencing were performed on a subset of HIV-positive subjects. HIV prevalences were highest among men who have sex with men (MSM; 2.0%-27.8%) and were found to be associated with multiple partners, noninjection drug use (non-IDU), and sexually transmitted infections (STIs). By comparison, much lower prevalences were noted among female commercial sex workers (FCSWs; 0%-6.3%) and were associated mainly with a prior IDU and STI history. Env subtype B predominated among MSM throughout the region (more than 90% of strains), whereas env subtype F predominated among FCSWs in Argentina and male commercial sex workers in Uruguay (more than 50% of strains). A renewed effort in controlling STIs, especially among MSM groups, could significantly lessen the impact of the HIV epidemic in South America.  相似文献   
63.
Monocyte-derived dendritic cells (mDC) are increasingly used as cancer vaccines. However, human monocytes are a heterogeneous cell population. We showed previously that DC derived from a monocyte subset expressing CD16 (16+mDC) stimulated allogeneic naïve T lymphocytes to secrete higher levels of IL-4 than DC derived from regular CD14highCD16? monocytes (16?mDC). Th1-type responses have been associated with effective antitumor responses, thus the use of mDC containing 16+mDC as cancer vaccines might be disadvantageous. Here, we evaluate the primary and memory immune response elicited in vitro by 16+mDC and 16?mDC in five patients with metastatic renal cell carcinoma vaccinated with autologous mDC pulsed with tumor lysates (TuLy) and keyhole limpet hemocyanin (KLH). After therapy, three of the five patients had stable disease. Surprisingly, patients with longer survival showed the highest amount of peripheral blood CD16+ monocytes. Analysis of KLH-specific antibodies revealed high titers of IgG2 in patients with longer survival. CD4+ T lymphocyte proliferation against KLH and TuLy increased after treatment, and some patients showed an augmented rate of CD4+ T lymphocyte proliferation against KLH (3/5) and TuLy (2/3) when 16+mDC were used as antigen presenting cells (APC). Before treatment, the IFN-γ/IL-4 ratio against TuLy and KLH was higher when using 16?mDC as APC, but after vaccination four of five patients had an increased ratio for TuLy with 16+mDC. These results suggest that the immune response elicited by 16?mDC and 16+mDC is modified when memory or naïve T cells are stimulated, and 16+mDC could favor a stronger and more beneficial antitumoral Th1 memory response in vivo.  相似文献   
64.
PEX7 encodes the cytosolic receptor for the set of peroxisomal matrix enzymes targeted to the organelle by the peroxisome targeting signal 2 (PTS2). Mutations in PEX7 cause rhizomelic chondrodysplasia punctata (RCDP), a distinct peroxisome biogenesis disorder. In previous work we described three novel PEX7 mutant alleles, including one, L292X, with a high frequency due to a founder effect. We have now extended our analysis to 60 RCDP probands and identified a total of 24 PEX7 alleles, accounting for 95% of the mutant PEX7 genes in our sample. Of these, 50% are L292X, 13% are IVS9+1G>C, and the remainder are mostly private. IVS9+1G>C occurs on at least three different haplotypes and thus appears to result from recurrent mutation. The phenotypic spectrum of RCDP is broader than commonly recognized and includes minimally affected individuals at the mild end of the spectrum. To relate PEX7 genotype and phenotype, we evaluated the consequence of the disease mutation on PEX7 RNA by Northern analysis and RT/PCR. We evaluated the function of the encoded Pex7 protein (Pex7p) by expressing selected alleles in fibroblasts from RCDP patients and assaying their ability to restore import of a PTS2 marker protein. We find that residual activity of mutant Pex7p and reduced amounts of normal Pex7p are associated with milder and variant phenotypes.  相似文献   
65.
We studied 10 cases of primary pure testicular neuroendocrine carcinoma. Patients were between 16 and 48 years old and had testicular swelling with pain or a painless testicular mass and no history of neuroendocrine carcinoma or other malignant neoplasm. All underwent orchiectomy. The tumors were low (n = 9) and intermediate (n = 1) grades with a variegated histologic appearance characterized by a nesting pattern, cords of neoplastic cells with rosettes, or sheets of neoplastic cells. Mitotic activity was lacking in 9 cases. In 1 case, mitotic figures ranged from 7 to 8 per 10 high-power fields, and cellular atypia and comedo-like necrosis were present. Immunohistochemical studies using a keratin cocktail, chromogranin, synaptophysin, epidermal growth factor, p53, placental-like alkaline phosphatase, and CD117 (c-kit) were performed in all cases. Keratin, chromogranin, and synaptophysin were positive in all tumors. Clinical follow-up information was obtained for 6 patients (range, 12-60 months): 5 with low-grade tumors were alive 24 to 60 months after diagnosis; 1 with an intermediate-grade tumor died of tumor 12 months after initial diagnosis. The behavior of these tumors, while in the testicular region, correlates well with the histologic grade. We propose replacing the term testicular carcinoid with neuroendocrine carcinoma, which better reflects the nature of these neoplasms.  相似文献   
66.
Biotinylation of human C8 with the water-soluble biotin derivative biotinylamidohexanoic acid, N-hydroxysulfosuccinimide ester is an excellent method for labelling this terminal complement component with preservation of its functional activity. The biotinylated product can be detected both in native form and also following its incorporation into the terminal complement complexes. Detection assays include Western blotting, crossed immunoblotting, ELISA, and immunocytochemistry. Biotinylation is an attractive alternative method for labelling C8 and may be used for detecting and quantifying C8 and C5b-9 complexes in their soluble and membrane-bound forms.  相似文献   
67.
The normal development of the ventricular outlets and proximal region of the great arteries is a controversial subject. It is known that the conus, truncus arteriosus (truncus), and aortic sac participate; however, there are some doubts as to the actual prospective fate of the truncus. Some authors propose that it gives origin to the proximal region of the great arteries and that the myocardial cells of its wall become smooth muscle. Nevertheless, others think that the truncus only forms the arterial valve apparatus and that therefore the myocardial cells transform into fibroblasts. As a first approach to beginning to elucidate which process occurs, the aim of this article was to study the histological changes in the wall of these components of the developing heart in chick embryos whose hearts had been labeled at the truncoconal boundary at stage 22HH, tracing the changes up to stage 36HH. Also, the histological constitution of the wall of the pulmonary arterial trunk and its valve apparatus were studied in the posthatching and adult hearts of chickens and rats. The conus and truncus walls were always encircled by a myocardial sleeve from the outset of their development. Between stages 26HH to 28HH, the truncal myocardial cells adjacent to the mesenchymal tissue of the ridges began to lose cell-to-cell contacts and invaded the extracellular matrix. At stage 24HH, the aortic sac began to project into the pericardial cavity and became divided into two channels by the aortic-pulmonary septum at stage 26HH. The wall of the aortic sac is mostly constituted by a compact mesenchymal tissue. Initially, it does not have smooth muscle but this starts to appear at stage 30HH. The insertion ring of the valves, a broad structure, was formed by mesenchymal tissue. Both structures were always covered by a myocardial sleeve. The leaflets developed from the truncal ridges, the segment immediately proximal to the aortic sac. Our results indicate that the proximal region of the pulmonary and aortic arteries do not originate from the truncus arteriosus; rather, we found that they take origin from the aortic sac. Thus, our findings agree with the proposal that the myocardial cells of the external sleeve of the truncus become fibroblastic and suggest that the insertion ring of the arterial valves has a dual origin: fibroblasts produced by truncal myocardial transdiferentiation and the mesenchymal tissue of the proximal region of the truncal ridges, while the leaflets have their origin from the truncal ridges. We discuss the fact that, because the truncus arteriosus does not give origin to the trunks of the aortic and pulmonary arteries, it may be necessary to modify terminology. Based on our results, together with the new findings obtained by in vivo labeling, immunostaining, a chimeric approach, and ultrastructural studies, we propose a developmental model that correlates the fate of the conus, truncus, and aortic sac with the normal morphogenesis of the ventricular outlet tracts and the trunks of the great arteries. (c) 2005 Wiley-Liss, Inc.  相似文献   
68.
Photobiological research in the last 30 yr has shown the existence of ultraweak photon emission in biological tissue, which can be detected with sophisticated photomultiplier systems. Although the emission of this ultraweak radiation, often termed biophotons, is extremely low in mammalian cells, it can be efficiently increased by ultraviolet light. Most recently it was shown that UV-A (330 to 380 nm) releases such very weak cell radiation in differentiated human skin fibroblasts. Based on these findings, a new and powerful tool in the form of UV-A-laser-induced biophotonic emission of cultured cells was developed with the intention to detect biophysical changes between carcinogenic and normal cells. With suspension densities ranging from 1 to 8 x 10(6) cells/mL, it was evident that an increase of the UV-A-laser-light induced photon emission intensity could be observed in normal as well as melanoma cells. Using this new detection procedure of ultraweak light emission, photons in cell suspensions as low as 100 microL could be determined, which is a factor of 100 lower compared to previous procedures. Moreover, the detection procedure has been further refined by turning off the photomultiplier system electronically during irradiation leading to the first measurements of induced light emission in the cells after less than 10 micros instead of 150 ms, as reported in previous procedures. This improvement leads to measurements of light bursts up 10(7) photons/s instead of several hundred as found with classical designs. Overall, we find decreasing induction ratings between normal and melanoma cells as well as cancer-prone and melanoma cells. Therefore, it turns out that this highly sensitive and noninvasive device enables us to detect high levels of ultraweak photon emission following UV-A-laser-induced light stimulation within the cells, which enables future development of new biophysical strategies in cell research.  相似文献   
69.
Abstract

The stethoscope is a major symbol of modern medicine. It is used for diagnosis of different conditions and enables physicians to listen to internal body sounds. Electrocardiography was only introduced in medicine in the beginning of the twentieth century. Today measuring heart’s electrical activity is also fundamental cardiac diseases diagnosis. Although performed with independent devices, requiring physician and patient presence in the same physical space, in combination they enhance cardiovascular assessment. In this paper, a digital stethoscope encapsulation was designed, adding new functionality to this advanced medical device. Today wired and wireless communications enable different medical devices to share data and information, over long distances. Using low-cost hardware technologies, the encapsulation will add the ability to acquire and transmit via Bluetooth the Electrocardiographic activity, determined in the same cardiac focus and synchronised with the Phonocardiographic sound recordings. Several encapsulation concepts were developed and prototyped using 3D printing. They were easily fitted to the digital stethoscope and tested in a hospital environment for ergonomics, acoustic and electric signals acquisition. The best concept was chosen with the help of a physician’s opinion and the final prototype performance was very satisfactory.  相似文献   
70.
Adenocarcinoma of the esophagus, or GEJ, has a poor prognosis. Early lesions [i.e. high grade dysplasia (HGD) or T1-carcinoma] are potentially curable. Local endoscopic therapies are promising treatment options for superficial lesions; however, for deeper lesions, surgical resection is considered to be the treatment of choice. To contribute to therapeutic decision-making, we retrospectively analysed the outcome of transhiatal esophagectomy in 120 patients with pathologically proven HGD (n=13) or T1-adenocarcinoma (n=107) of the distal esophagus or gastro-esophageal junction (GEJ). Tumors were subdivided into six different depths of invasion (T1-mucosal m1-m3, T1-submucosal sm1-sm3), and the frequency of lymphatic dissemination and time to locoregional and/or distant recurrence were analysed. Only one of the 79 T1m1-3/sm1 tumors (1%) showed lymph node metastases as compared with 18 out of 41 T1sm2-3 tumors (44%). There was a significant difference in recurrence-free period between T1m1-m3/sm1 versus T1sm2-sm3 tumor patients (P log rank <0.0001), with 5-year recurrence-free percentages of 97% and 57%, respectively. In multivariate analysis including age, gender, tumor differentiation grade, N-stage and depth of invasion, only N-stage was an independent prognostic factor for recurrence-free period (hazard rate=5.9, 95% CI 1.7–20.7). However, if N-stage was excluded from analysis, only depth of invasion (T1sm2-3 versus T1m1-m3/sm1) was an independent prognostic factor for recurrence-free period (hazard rate=7.5, 95% CI 2.0–27.7). These data indicate that T1m1-m3/sm1 adenocarcinomas of esophagus or GEJ show a very low risk of lymphatic dissemination and are therefore eligible for local endoscopic therapy. After transhiatal surgical resection, almost half of the patients with T1sm2-sm3 lesions develop recurrent disease within 5 years, and therefore need additional therapy to improve survival.  相似文献   
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