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991.
Ranmali Waduge G N Malavige M Pradeepan Chandrika N Wijeyaratne Sirimali Fernando Suranjith L Seneviratne 《Journal of clinical virology》2006,37(1):27-33
BACKGROUND: Dengue is a major public health problem in several countries. Few reports document presentations and outcomes of dengue during pregnancy. In many endemic countries as the average age of getting dengue infections is shifting upwards, dengue in pregnancy is likely to be encountered more frequently. Patterns of dengue in patients from different regions are needed if we are to draft evidence based management guidelines. OBJECTIVES: To document clinical and laboratory findings in a cohort of hospitalised patients with dengue during pregnancy in Sri Lanka and compare their presentation and outcomes with previously published cases. STUDY DESIGN: Clinical, laboratory, maternal and fetal outcomes and demographic information were collected from patients with confirmed dengue infections during pregnancy treated in a Maternity Hospital in Sri Lanka from 1 January 2000 to 30 June 2004. The Medline database was searched to identify reports relating to dengue infection during pregnancy since 1965. RESULTS: Twenty-six patients [mean (S.D.) age: 29 (4.2) years] were studied. One (3.8%), 2 (7.7%) and 20 (77%) presented in the first, second and third trimesters of pregnancy, and 3 (11.5%) in the immediate post-partum period. Seventeen (65.3%) had primary and nine (34.7%) secondary dengue infections. Ten (38.5%) had DF, 6 (23.1%): DHF grade I and 10 (38.5%): DHF grade II. Five (19.2%) and three (11.5%) patients who first presented with cough/breathlessness or vaginal bleeding, were initially managed as having a pulmonary embolism or a primary obstetric cause for their vaginal bleeding. Bradycardia was noted in three of the four patients who had a cardiac arrhythmia. Seven (26.9%) needed admission to an ICU. Raised AST and ALT levels were seen in 81.2% and 43.7% of 16 patients in whom liver function tests results were available. No fetal malformations were seen in any of the babies born. The single patient who developed DHF in the first trimester had an abortion while having acute symptoms of dengue. CONCLUSIONS: Awareness of clinical and laboratory manifestations of dengue in pregnancy should allow its early recognition and institution of appropriate treatment. Reports on dengue in pregnancy from different regions should allow more evidence-based guidelines to be formulated for optimum evaluation and care of such patients. Our data contributes towards this goal. 相似文献
992.
Ontogenetic changes in the skull and mandible of thirty‐one specimens of Galesaurus planiceps, a basal non‐mammaliaform cynodont from the Early Triassic of South Africa, are documented. The qualitative survey indicated eight changes in the craniomandibular apparatus occurred during growth, dividing the sample into three ontogenetic stages: juvenile, subadult, and adult. Changes in the temporal region, zygomatic arch, occiput, and mandible occurred during the transition from the subadult to adult stage at a basal skull length of 90 mm. At least four morphological and allometric differences divided the adult specimens into two morphs, indicating the presence of sexual dimorphism in Galesaurus. Differences include extensive lateral flaring of the zygomatic arches in the “male” morph resulting in a more anterior orientation of the orbits, and a narrower snout in the “female”. This is the first record of sexual dimorphism in a basal cynodont, and the first time it is quantitatively documented in a non‐mammaliaform cynodont. An ontogenetic comparison between Galesaurus and the more derived basal cynodont Thrinaxodon revealed differences in the timing and extent of sagittal crest development. In Galesaurus, the posterior sagittal crest, located behind the parietal foramen, developed relatively later in ontogeny, and the anterior sagittal crest rarely formed suggesting the anterior fibres of the temporalis were less developed than in Thrinaxodon. In contrast, craniomandibular features related to the masseters became more developed during the ontogeny of Galesaurus. The development of the adductor musculature appears to be one of the main factors influencing skull growth in these basal non‐mammaliaform cynodonts. Anat Rec, 300:353–381, 2017. © 2016 Wiley Periodicals, Inc. 相似文献
993.
Bracho MA Gosalbes MJ González F Moya A González-Candelas F 《Journal of clinical microbiology》2006,44(4):1288-1294
In order to establish the transmission pathway for two outbreak patients affected by fulminant hepatitis B (FHB) following a shared period of hospitalization, we sequenced the complete genomes of the hepatitis B viruses (HBV) isolated from them as well as from the suspected common source and 11 additional controls. Phylogenetic and statistical analyses of these sequences revealed that the two FHB patients were indeed infected by a common source and that the fatal development of the disease did not appear to be associated with any mutation previously reported to be related to FHB. These data have also allowed us to estimate the extent and distribution of genetic variability along the genomes of HBV genotype D samples from the same source population. As a result of these analyses, we provide an improved statistical method to individualize the assignment of each suspected patient and the source of an outbreak and information on which genome region to analyze in the molecular epidemiological assessment of hepatitis B virus transmission cases. 相似文献
994.
995.
996.
Rojas OL Caicedo L Guzmán C Rodríguez LS Castañeda J Uribe L Andrade Y Pinzón R Narváez CF Lozano JM De Vos B Franco MA Angel J 《Viral immunology》2007,20(2):300-311
In a double blind trial, 319 fully immunized children received two doses of either placebo or 10(6.7) focus-forming units of the attenuated RIX4414 human rotavirus (RV) vaccine ("all-in-one" formulation). Plasma RV-specific IgA (RV IgA), stool RV IgA, and circulating total and RV memory B cells (CD19+ IgD+/- CD27+) with an intestinal homing phenotype (alpha4beta7+ CCR9+/-) were measured, after the first and second doses, as potential correlates of protection. After the first and/or second dose, 54% of vaccinees and 13% of placebo recipients had plasma RV IgA. Before vaccination, most (95%) of the children (of both study groups) were breast-fed and had stool RV IgA (68.64%). Coproconversion (4-fold increase) after the first and/or second dose was observed in 32.7% of vaccinees and 17.4% of placebo recipients. No significant difference was seen when comparing the frequencies of any subset of memory B cells between vaccinees and placebo recipients. Statistically significant weak correlations were found between plasma RV IgA titers and coproconversion, and several subsets of memory B cells. The vaccine provided 74.8% protection (95% confidence interval, 30.93-92.62) against any RV gastroenteritis and 100% protection (95% confidence interval, 14.53-100) against severe RV gastroenteritis. When vaccinees and placebo recipients were considered together, a correlation was found between protection from disease and plasma RV IgA measured after dose 2 and RV memory (IgD- CD27+ alpha4beta7+ CCR9+) circulating B cells measured after dose 1. However, the correlation coefficients for both tests were low (<0.2), suggesting that other factors are important in explaining protection from disease. 相似文献
997.
Glioblastomas: correlation between oligodendroglial components, genetic abnormalities, and prognosis
Pinto LW Araújo MB Vettore AL Wernersbach L Leite AC Chimelli LM Soares FA 《Virchows Archiv : an international journal of pathology》2008,452(5):481-490
It has been demonstrated that a small percentage (approximately 15%) of glioblastomas (GBM) presents an oligodendroglial component
with a variable frequency of chromosome 1p and 19q deletions, the genetic alteration related to chemotherapy response and
longer survival in oligodendrogliomas. There is a growing interest in investigating 1p and 19q losses in hybrid gliomas and
their impact on prognosis. A series of 88 GBMs was investigated regarding 1p and/or 19q losses, 24 with oligodendroglioma-like
areas, using quantitative microsatellite analysis and/or fluorescent in situ hybridization. When present, the oligodendroglial
and astrocytic components were independently investigated. Clinical data, histology, and 1p/19q status were correlated. Tumors
with oligodendroglial components showed three cases each of 1p or 19q loss and one with combined 1p/19q loss. No difference
in 1p or 19q status was observed between the oligodendroglial and astrocytic components. Conventional GBM demonstrated isolated
1p loss in four cases and 19q loss in five. No association was seen between 1p/19q status and histology. Deletions at 1p and/or
19q were infrequent in GBMs with oligodendroglial components. Despite the hybrid phenotype, the pattern of genetic changes
at 1p and 19q was not different from that usually observed in conventional GBMs, nor did it show any correlation with survival. 相似文献
998.
Immune responses induced by the Leishmania (Leishmania) donovani A2 antigen,but not by the LACK antigen,are protective against experimental Leishmania (Leishmania) amazonensis infection 下载免费PDF全文
Coelho EA Tavares CA Carvalho FA Chaves KF Teixeira KN Rodrigues RC Charest H Matlashewski G Gazzinelli RT Fernandes AP 《Infection and immunity》2003,71(7):3988-3994
Leishmania amazonensis is one of the major etiologic agents of a broad spectrum of clinical forms of leishmaniasis and has a wide geographical distribution in the Americas, which overlaps with the areas of transmission of many other Leishmania species. The LACK and A2 antigens are shared by various Leishmania species. A2 was previously shown to induce a potent Th1 immune response and protection against L. donovani infection in BALB/c mice. LACK is effective against L. major infection, but no significant protection against L. donovani infection was observed, in spite of the induction of a potent Th1 immune response. In an attempt to select candidate antigens for an American leishmaniasis vaccine, we investigated the protective effect of these recombinant antigens (rLACK and rA2) and recombinant interleukin-12 (rIL-12) against L. amazonensis infection in BALB/c mice. As expected, immunization with either rA2-rIL-12 or rLACK-rIL-12 induced a robust Th1 response prior to infection. However, only the BALB/c mice immunized with rA2-rIL-12 were protected against infection. Sustained gamma interferon (IFN-gamma) production, high levels of anti-A2 antibodies, and low levels of parasite-specific antibodies were detected in these mice after infection. In contrast, mice immunized with rLACK-rIL-12 displayed decreased levels of IFN-gamma and high levels of both anti-LACK and parasite-specific antibodies. Curiously, the association between rA2 and rLACK antigens in the same vaccine completely inhibited the rA2-specific IFN-gamma and humoral responses and, consequently, the protective effect of the rA2 antigen against L. amazonensis infection. We concluded that A2, but not LACK, fits the requirements for a safe vaccine against American leishmaniasis. 相似文献
999.
Rotavirus diarrhea severity is related to the VP4 type in Mexican children 总被引:6,自引:0,他引:6 下载免费PDF全文
Mota-Hernández F Calva JJ Gutiérrez-Camacho C Villa-Contreras S Arias CF Padilla-Noriega L Guiscafré-Gallardo H de Lourdes Guerrero M López S Muñoz O Contreras JF Cedillo R Herrera I Puerto FI 《Journal of clinical microbiology》2003,41(7):3158-3162
This report is of a community-based case control study to assess whether the severity of acute diarrhea by rotavirus (RV) in young children is associated with a particular VP7 (G) or VP4 (P) RV serotype. Five hundred twenty children younger than 2 years of age with diarrhea lasting less than 3 days were age and gender matched with 520 children with no diarrhea. The G and P serotypes were determined with specific monoclonal antibodies, and the VP4 serotype specificity in a subgroup was confirmed by genotyping. Infection with a G3 serotype led to a higher risk of diarrhea than infection with a G1 serotype. Infection with a G3-nontypeable-P serotype was associated with more severe gastroenteritis than infection with a G3 (or G1) P1A[8] serotype. A child with diarrhea-associated dehydration was almost five times more likely to be infected with a G3-nontypeable-P serotype than a child without dehydration (P < 0.001). Moreover, the two predominant monotypes within serotype P1A[8] had significantly different clinical manifestations. In this study, the severity of RV-associated diarrhea was related to different P serotypes rather than to G serotypes. The relationship between serotype and clinical outcomes seems to be complex and to vary among different geographic areas. 相似文献
1000.
Bedoya A Garay J Sanzón F Bravo LE Bravo JC Correa H Craver R Fontham E Du JX Correa P 《Human pathology》2003,34(3):206-213
Infection with Helicobacter pylori has been recognized as a cause of gastric carcinoma. Although the neoplasia is always detected in adults, the infection starts in childhood. It has been reported that early age at first infection is a determinant of gastric cancer risk. In this study, we examined the histopathology of the gastric mucosa in infected children from a population at high risk for gastric cancer (Pasto, Colombia) and compared it with that of a lower-risk population (New Orleans, LA). Gastric biopsies obtained from antrum and corpus were stained with hematoxylin and eosin and Steiner's silver method. Immunohistochemical stains were used to identify B lymphocytes (CD20), T lymphocytes (CD3 and CD8), macrophages (CD68), and polymorphonuclear neutrophil myeloperoxidase. Morphometric techniques were used to evaluate the immunohistochemical stains. In both populations, the inflammatory lesions were seen predominantly in the antrum. Compared with children from the lower-risk populations, children from the higher-risk population exhibited more severe polymorphonuclear neutrophil infiltration, stromal and intraepithelial lymphocyte infiltration, mucus depletion, and H. pylori colonization density. Regenerative activity was significantly more marked in the lower-risk population. Morphometric analysis of immunohistochemical stains showed increased representation of T lymphocytes and macrophages in the higher-risk population. Most T lymphocytes stained positive for CD8, a marker of suppressor/cytotoxic cells. B lymphocytes were relatively more abundant in the lower-risk population. The possibility that the aforementioned characteristics of H. pylori infection in children are related to cancer risk in adults is discussed. 相似文献