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111.
112.
Since its inception in November 1997, the Cervical Cancer Screening Program of Paraná (CCSPP), Brazil, has resulted in the cytological screening of 2,244,158 women, the coverage of the female population increasing from 43% to 86%. One thousand six hundred one cases screened by cytology, submitted to colposcopy, and subjected to treatment were selected. Cytopathological results were compared with those obtained on the basis of histological analyses of the loop electrical excision procedure specimens, and were subjected to statistical analyses. The data obtained were then compared with cytohistological correlation results from the first year of the program. Considering the exact correlation between cytological and histological diagnoses, the correlation index increased from 53.34% in the first year to 67.3% at the end of 5 yr of the program. Variations that occurred in each diagnostic category are discussed. This study demonstrates a significant improvement in the concordance between cytological and histological results for the 5-yr period compared with the first year of the CCSPP.  相似文献   
113.
114.
Duck virus enteritis is an acute contagious viral disease affecting birds of the order Anseriformes (ducks, geese and swans). The disease agent is a member of the Herpesviridae family (Anatidae herpes virus 1). A group of Anseriformes waterfowl from a Nature Reserve and Centre for the Recovery of Endangered Species in Spain suffered an outbreak of the disease, affecting adults, young and newborns. Other non-Anseriformes waterfowl such as coots, from the family Rallidae, order Gruiformes, were also affected. Histopathological and ultrastructural findings confirmed the viral infection. The present study provides evidence that birds different from the order Anseriformes can be affected, suggesting that the virus has the ability to infest other non-Anseriformes waterfows.  相似文献   
115.
In chronically HIV infected individuals, a number of functional B cell abnormalities have been described. However, the immediate changes that occur in the B cell compartment following viral exposure and how they affect the long-term course of infection are not well understood. We report the longitudinal analysis of B cell repertoires during early infection in untreated and treated individuals receiving highly active antiretroviral therapy (HAART). Analysis was based on IgG heavy chain gene utilization and CDR3 length measurement and relationship with CD4/CD8 counts, viral load, and total serum IgG, and anti-HIV antibodies levels. Repertoires were assessed at baseline and at weeks 2, 4, 12, 24, and 72 after initiation of therapy. The findings indicate a stable peripheral B cell repertoire during the first 72 weeks following infection, particularly in the HAART treated patients. A modest association between B cell repertoire integrity and viremia levels as well as treatment was detected.  相似文献   
116.
The severity of acute pancreatitis results from the transmigration and activation of leukocytes within the pancreas and the local synthesis and release of proinflammatory-soluble mediators that transform a local injury into a systemic inflammatory response. Poly(ADP-ribose)polymerase-1 (PARP-1) is a nuclear DNA-binding protein that has been shown to play a relevant role in cell necrosis and organ failure in various diseases associated with inflammation. Therefore, we set out to investigate whether the genetic deletion of PARP-1 or PARP-2 (a new member of the PARP family) genes, or pharmacological inhibition of PARP activity might affect the development and severity of acute pancreatitis and pancreatitis-associated lung injury. Secretagogue-induced acute pancreatitis was achieved by 12 hourly intraperitoneal injections of cerulein in mice deficient in PARP-1 or PARP-2 genes, and wild-type (WT) littermate mice untreated or treated with PARP activity inhibitors. The severity of pancreatitis was assessed by measurements of serum amylase, lipase, interleukin-1beta and IL-6, pancreatic water content, histologic grading and pancreas myeloperoxidase (MPO) activity. Lung injury was evaluated by quantifying MPO activity and morphological changes. We found that the severity of acute pancreatitis and pancreatitis-associated lung injury was significantly attenuated in mice lacking PARP-1, but not PARP-2, compared with WT mice. Interestingly, administration of PARP inhibitors, 3-aminobenzamide or PJ34 (N-(6-oxo-5,6-dihydro-phenanthridin-2-yl)-N,N-dimethyacetamide HCl), in WT mice markedly decreased acute pancreatitis severity and pulmonary-associated injury in a larger extension than genetic deletion of PARP-1. Our results support the potential therapeutic application of PARP inhibitors in the development and severity of acute pancreatitis and associated lung injury.  相似文献   
117.
BACKGROUND: The presence of the three forms of IgE receptor - the heterotrimeric high-affinity receptor for IgE (Fc(epsilon)RI), the low-affinity receptor for IgE (Fc(epsilon)RII/CD23) and the Mac-2/IgE-binding protein (epsilonBP) - has been demonstrated on human neutrophils. We have previously shown that specific allergens are able to activate functional responses by neutrophils from allergic patients sensitized to those allergens. Neutrophils are present at the sites of allergic inflammation. The primary (azurophilic) granules of neutrophils contain a variety of enzymes, such as elastase, that might potentiate inflammation. It is not known whether specific allergens are able to elicit elastase release by neutrophils from allergic patients. In addition, we attempted to evaluate the relationship between neutrophil degranulation and lung function of the patients, measured as FEV(1). METHODS: Neutrophils were challenged in vitro with the specific allergens that produced clinical symptoms in asthmatic patients. The cells were also challenged with allergen to which the patients were not sensitive. Neutrophils from normal subjects were challenged with allergens as control. RESULTS: The in vitro challenge of neutrophils with allergens to which the patients were sensitive elicited a release of elastase by these cells. The in vitro activation of neutrophils was highly allergen specific; allergens other than those accounting for clinical symptoms did not evoke elastase release, and allergens were ineffective on neutrophils from healthy donors. A significant inverse correlation was observed between elastase release and patients' lung function, measured as FEV(1). CONCLUSION: An IgE-dependent mechanism might promote elastase release by neutrophils at allergic sites. There is a significant inverse relationship between levels of elastase released by neutrophils from allergic patients and lung function, as assessed by FEV(1).  相似文献   
118.
Three new missense mutations (H15D, A83D, and A179D) and a new splicing defect (573 + 1G→A) in the 5′ splice site of intron 5 were among six mutant adenosine deaminase (ADA) alleles found in three unrelated patients with severe combined immunodeficiency disease, the most common phenotype associated with ADA deficiency. When expressed in vitro, the H15D, A83D, and A179D proteins lacked detectable ADA activity. The splicing defect caused skipping of exon 5, resulting in premature termination of translation and a reduced level of mRNA. H15D is the first naturally occurring mutation of a residue that coordinates directly with the enzyme-associated zinc ion. Molecular modeling based on the atomic coordinates of murine ADA suggests that the D15 mutation would create a cavity or gap between the zinc ion and the side chain carboxylate of D15. This could alter the ability of zinc to activate a water molecule postulated to play a role in the catalytic mechanism. A83 and A179 are not directly involved in the active site, but are conserved residues located respectively in a helix 4 and β strand 4 of the α/β barrel. Replacement of these small hydrophobic Ala residues with the charged, more bulky Asp side chain may distort ADA structure and affect enzyme stability or folding.© 1995 wiley-Liss, Inc.  相似文献   
119.
In this study we utilized the hamster ovary as a model to investigatethe effects of ovulation induction with gonadotrophin on theactivation of the signal transducer effector system, adenylylcyclase (AC). For this purpose, we prepared membrane particlesfrom the ovary and analysed both gonadotrophin-sensitive ACand non-receptor-mediated activation during a cycle in whichovulation and luteinization were achieved by pregnant mare’sserum gonadotrophin (PMSG)/human chorionic gonadotrophin (HCG)administration. Results were directly compared with AC activationin similarly prepared membranes obtained at different stagesof the natural unstimulated cycle. AC activity was quantifiedby the direct conversion of ATP substrate into cyclic adenosinemonophosphate (cAMP). Measurements of ovarian weights, serumoestradiol and progesterone concentrations provided a solidbase from which to evaluate the functional status of the ovaryat each time period during the natural and stimulated cycles.We found that ovarian membranes contain functional componentsof the AC system and demonstrated that AC is highly dependenton hormonal changes and the functional state of the ovary. Thus,during the natural cycle, ovarian AC showed relatively constantresponsiveness to follicle-stimulating hormone (FSH) throughoutthe cycle, whereas responsiveness to luteinizing hormone (LH)/HCGreached its peak during the luteal phase. On the other hand,during the stimulated cycle, sensitivity to FSH and LH/HCG variedconsiderably, being absent during the peri-ovulatory period.AC responsiveness to gonadotrophins was only regained 48 h afterovulation. Also during the peri-ovulatory period of the gonadotrophin-inducedcycle, stimulation of ovarian AC with non-hormonal activatorsdeclined. However, the rate of cAMP production in response tothese activators remained very high, indicating that despiterefractoriness to gonadotrophins, ovarian AC retained the capacityto generate cAMP at near maximal efficiency. Basal (non-stimulated)activity, guanine nucleotide activation, hormone responsivenessand stimulation by the non-hormonal activators NaF and forskolinwere all significantly increased in comparison with the naturalcycle. Basal activity alone was 7-fold higher than the activityobserved during the unstimulated cycle. These results suggestthat subsequent to exogenous gonadotrophin administration, thetransmembrane effector AC system must be primed for a higherlevel of activity in the ovarian tissue. This priming of theovarian AC system by exogenous gonadotrophin was also evidentwhen the enzyme was measured under conditions allowing maximalactivity, i.e. in the presence of a combination of NaF and forskolin.Maximal AC activity increased 4- to 5-fold compared with thenatural cycle. We conclude that gonadotrophin administrationinducing ovulation causes profound alterations in the expressionof AC in ovarian membranes. Gonadotrophin treatment increasedthe enzyme activity and induced a temporal desensitization toFSH and LH/HCG in the peri-ovulatory period of the stimulatedcycle. Because the gonadotrophin-sensitive AC system representsthe capacity of FSH and LH/HCG receptors to couple and elicita biological response, our results provide new insights intothe cellular mechanisms that regulate ovarian activity duringinduction of ovulation.  相似文献   
120.
Myxoid leiomyosarcoma of the ovary: Analysis of three cases   总被引:2,自引:0,他引:2  
The first three cases of myxoid leiomyosarcoma occurring in the ovary are reported. Two cases in stage III were found in postmenopausal patients and a further case was found in stage I in a 32-year-old. All masses were large and gelatinous with cystic change, necrosis, and hemorrhage, but both uteri and ligaments and contralateral adnexa appeared normal. Microscopically, the tumors showed a predominantly reticular meshwork of elongated cells surrounded by abundant basophilic material. While electron microscopy proved inconclusive due to nondifferentiation, the use of monoclonal antibodies against smooth muscle actin demonstrated a smooth muscle type of differentiation. The differential diagnosis of this rare ovarian condition includes other myxoid ovarian lesions, such as ovarian edema, myxoma, endodermal sinus tumors, and the sarcomatous component of malignant mixed müllerian tumor and carcinosarcoma, as well as lymphovascular tumors. Since mitotic count due to decreased cellular density is unusually low in myxoid leiomyosarcoma, capsular rupture and clinical stage seem to be more reliable prognostic markers. The highly aggressive behavior of myxoid leiomyosarcoma parallels that of typical ovarian leiomyosarcoma. Two of the three patients in this series died of tumor at 13 and 24 months after diagnosis; the other patient is free of disease at 3 years after diagnosis.  相似文献   
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