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1.
Oocyte development has been divided into 5 distinct stages in the reared matrinx?, Brycon cephalus, based on morphological criteria by light and transmission electron microscopy: I) chromatin-nucleolus; II) perinucleolar; III) cortical alveoli; IV) vitellogenesis; V) final maturation. In stages I and II (primary growth), oocytes reside in nests close to other oocytes (chromatin-nucleolus phase) and then within a definitive follicle (perinucleolar phase) where they greatly increase in size (the Balbiani vitelline body is the main cytoplasmic component in these latter oocytes), respectively. In stage III (cortical alveolus phase) oocytes are distinguished by the appearance of variably sized cortical alveoli and the number of these structures increases steadily towards hydration. The vitelline envelope becomes prominent. In the process of vitellogenesis (stage IV) one major accumulation of yolk proteins occurs in oocytes. In stage V (final maturation), oocyte increase slightly in size. Follicle cells go through a primordial stage and later change to a squamous and to a cubical shape. The chorion grows to a tripartite structure: an outer thin porous layer, an intermediate homogenous layer and an inner thick helicoidal layer. The ovulation of females matrinx?, required hormonal stimulation and this occurred 6 and 8 h after the second application.  相似文献   
2.

Objectives

Malaria infection may impact on mother‐to‐child transmission (MTCT) of HIV‐1. Prevention of malaria in pregnancy could thus potentially affect MTCT of HIV. We studied the impact of intermittent preventive treatment during pregnancy (IPTp) on HIV‐1 MTCT in southern Mozambique.

Methods

A total of 207 HIV‐positive Mozambican pregnant women were enrolled in the study as part of a randomized placebo‐controlled trial of two‐dose sulfadoxine‐pyrimethamine (SP) IPTp in women receiving single‐dose nevirapine to prevent MTCT of HIV. HIV RNA viral load, maternal anaemia and peripheral and placental malaria were assessed at delivery. Infant HIV status was determined by DNA polymerase chain reaction (PCR) at 1 month of age.

Results

There were 19 transmissions of HIV in 153 mother–infant pairs. IPTp with SP did not have a significant impact on MTCT (11.8% in the SP group vs. 13.2% in the placebo group; P=0.784) or on maternal HIV RNA viral load [16 312 (interquartile range {IQR} 4076–69 296) HIV‐1 RNA copies/mL in the SP group vs. 18 274 (IQR 5471–74 104) copies/mL in the placebo group; P=0.715]. In multivariate analysis, maternal HIV RNA viral load [adjusted odds ratio (AOR) 19.9; 95% confidence interval (CI) 2.3–172; P=0.006] and anaemia (haematocrit <33%; AOR 7.5; 95% CI 1.7–32.4; P=0.007) were independent risk factors for MTCT. Placental malaria was associated with a decrease in MTCT (AOR 0.23; 95% CI 0.06–0.89; P=0.034).

Conclusions

IPTp with SP was not associated with a significant impact on MTCT of HIV. Maternal anaemia was an independent risk factor for MTCT.  相似文献   
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Sequestration of Plasmodium falciparum-infected erythrocytes (PfIE) in the capillaries of the central nervous system (CNS) is the pathognomonic feature of cerebral malaria, a condition frequently leading to death. Sequestration of PfIE in the placental intervillous spaces is the characteristic feature of malaria in pregnancy and is associated with low birthweight and prematurity. Although both patterns of sequestration are thought to result from the expression of different parasite proteins involved in cytoadhesion to human receptors, scant information exists on whether both conditions can coexist and whether this can lead to death. We conducted a prospective autopsy study including all consecutive pregnancy-related deaths in a tertiary-level referral hospital in Maputo, Mozambique, between October 2002 and December 2006. Extensive sampling of all major viscera was performed. All cases showing parasites in any of the viscera were included in the analysis. From 317 complete autopsies PfIEs were identified in ten women (3.2%). All cases showed massive accumulation of PfIE in small capillaries of the CNS but also in most visceral capillaries (heart, lung, kidney, uterus). Placental tissue, available in four cases, showed a massive accumulation of maternal PfIE in the intervillous space. Coma (six women) and dyspnoea (five women) were the most frequent presenting clinical symptoms. In conclusion, massive visceral sequestration of PfIE with significant involvement of the CNS is an infrequent but definite direct cause of maternal death in endemic areas of Africa. The PfIE sequestered in cerebral capillaries and the placenta coexist in these fatal cases.  相似文献   
5.
The sick placenta-the role of malaria   总被引:11,自引:0,他引:11  
The human placenta is an ideal site for the accumulation of Plasmodium falciparum malaria parasites, and as a consequence serious health problems arise for the mother and her baby. The pathogenesis of placental malaria is only partially understood, but it is clear that it leads to a distinct epidemiological pattern of malaria during pregnancy. The objectives of this review are: (1) To review recent data on the epidemiology of malaria in pregnancy, with emphasis on placental malaria; (2) to describe the pathological changes and immunological factors related to placental malaria; and (3) to discuss briefly the functional consequences of this infection for the mother and her baby. The review attempts to bring together local events at the maternal-fetal interface which encompass immunological and pathological processes which relate to the epidemiological pattern of malaria in pregnancy in areas of both high and low malaria transmission. An integrated understanding of the epidemiological, immunological and pathological processes must be achieved in order to understand how to control malaria in pregnancy. The yearly exposure of at least 50 million pregnancies to malaria infection makes it the commonest and most recurrent parasitic infection directly affecting the placenta. These statistics and our limited understanding of its pathogenesis suggest the research priorities on this subject.  相似文献   
6.
BACKGROUND: Primary carcinomas of the fallopian tube are rare and their preoperative diagnosis is difficult due to the lack of specific symptoms. CASES: We present two tumors diagnosed in women 74 and 77 years old. On examination both patients presented as acute pelvic peritonitis with abdominal pain and tenderness with guarding and rebound, as well as fever and leukocytosis. At surgery, a left tubal carcinoma was found in each patient. Marked inflammatory and purulent reaction involving the uterus, the adnexa, and the pelvic peritoneum, and no abnormalities in the digestive tract were identified. A total hysterectomy with bilateral salpingo-oophorectomy was performed in both patients. CONCLUSION: Carcinoma of the fallopian tube should be considered in the differential diagnosis of pelvic peritonitis, a previously poorly reported clinical presentation.  相似文献   
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8.
A 37-year-old woman a diagnosis of squamous carcinoma of the tongue and a history of partial/hemiglossectomy with cervical lymphadenectomy and postoperative radiotherapy was scheduled for biopsy under general anesthesia given the suspicion of local recurrence. She underwent routine preparation for intubation with a fiberoptic bronchoscope with topical anesthesia of mucosal tissue without sedation. Syncope and asystole presented suddenly during intubation and external cardiopulmonary resuscitation and difficult ventilation through a face mask were necessary. She was finally intubated using a retrograde technique and recovered heartbeat after 20 minutes. No neurological sequelae were observed over the next few days. The etiologic diagnosis of this rare complication was later based on the appearance of the characteristic clinical profile of glossopharyngeal neuralgia-asystole syndrome in combination with parapharyngeal space lesion syncope syndrome; magnetic resonance findings of extensive neoplastic invasion of the space confirmed the diagnosis. Endotracheal intubation with a fiberoptic bronchoscope plays an important role in the management of the anticipated difficult airway. It is safe in the awake patient and facilitates the identification of structures, particularly when there are anatomical alterations due to neoplastic invasion, surgery, or radiotherapy. In the patient we describe, however, stimulation caused asystole.  相似文献   
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10.
Around 20% to 30% of patients with Hodgkin lymphoma (HL) do not benefit from standard therapies and finally succumb to their disease. The factors that influence the outcome of HL have not been elucidated, underscoring the demand for the identification of biologic risk factors and new therapeutic targets. We analyzed the gene expression profiles of samples from 29 patients with advanced classic HL treated with standard therapy and compared the expression profiles of patients with favorable and unfavorable clinical outcome. Using supervised methods, we identified 145 genes associated with outcome, which were grouped into 4 signatures representing genes expressed by either the tumoral cells (genes involved in the regulation of mitosis and cell growth/apoptosis) or the tumor microenvironment. The relationship between the expression of 8 representative genes and survival was successfully validated in an independent series of 235 patients by quantification of protein expression levels on tissue microarrays. Analysis of centrosomes and mitotic checkpoint confirmed the existence of an abnormal transition through mitosis in HL cells. Therefore, genes related to tumor microenvironment, cell growth/apoptosis, and regulation of mitosis are associated with treatment response and outcome of patients with HL.  相似文献   
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