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31.
Logistic, economic, and technical factors limit rapid access to microscopic confirmation of malaria in many tropical countries, including India. The occurrence of high-grade fever and three deaths during the hot summer months in some forest migrants created an emergency situation in Jabalpur in central India. A cheap and rapid malaria test, Paracheck Pf, was tested in this group of migrants in parallel with microscopy. The indigenous population at the site of occupational activities of these migrants approximately 250 km from Jabalpur was also screened by both methods. The results of this field investigation are very encouraging. Among migrants, the test had a sensitivity of 100% and a specificity of 67%. The positive and negative predictive values were 94% and 100%, respectively. Among indigenous population, the corresponding values were 100%, 97.3%, 98.4%, and 100%, respectively, indicating the usefulness of test as a diagnostic tool for providing on-site confirmation of symptomatic diagnosis of Plasmodium falciparum malaria. 相似文献
32.
The abuse of the illicit drug methamphetamine (METH) is a major concern because it can cause terminal degeneration and neuronal cell death in the brain. METH-induced cell death occurs via processes that resemble apoptosis. In the present review, we discuss the role of various apoptotic events in the causation of METH-induced neuronal apoptosis in vitro and in vivo. Studies using comprehensive approaches to gene expression profiling have allowed for the identification of several genes that are up-regulated or down-regulated after an apoptosis-inducing dose of the drug. Further experiments have also documented the fact that the drug can cause demise of striatal enkephalinergic neurons by cross-talks between mitochondria-, endoplasmic reticulum- and receptor-mediated apoptotic events. These neuropathological observations have also been reported in models of drug-induced neuroplastic alterations used to mimic drug addiction (Nestler, 2001). 相似文献
33.
Histomorphometric Analysis of Postnatal Glomerulogenesis in Extremely Preterm Infants 总被引:6,自引:0,他引:6
Maria M.?RodríguezEmail author Alexander H.?Gómez Carolyn L.?Abitbol Jayanthi J.?Chandar Shahnaz?Duara Gastón E.?Zilleruelo 《Pediatric and developmental pathology》2004,7(1):17-25
Until now oligonephropathy to indicate too few nephrons has been associated with intrauterine growth restriction and experimentally induced abnormalities of renal development. The purpose of this study was to determine whether there is evidence of abnormal postnatal glomerulogenesis in extremely low birth weight preterm infants. Renal autopsy tissue was studied by computer-assisted morphometry from 56 extremely premature infants (birth weight 1000 g) and 10 fullterm infants as controls. Preterm infants were divided into two groups (short survival < 40 days vs. long survival 40 days). Each group was subdivided into those with renal failure (RF) and those with normal renal function. Forty-two of 56 preterm infants (75%) were adequate for gestational age. Glomerulogenesis as measured by radial glomerular counts (RGC) was markedly decreased in all preterm infants as compared to term controls and correlated significantly with gestational age (r = 0.87; P < 0.001). Active glomerulogenesis with basophilic S-shaped bodies was absent in longer surviving preterm and all term infants. RGC of preterm infants surviving 40 days with RF were significantly less than RGC of those with long survival and no RF (P < 0.001). Only this latter group demonstrated increased glomerular size as measured by mesangial tuft area and Bowmans capsule area compared to all other groups (P < 0.001). The kidney continues to form postnatally in preterm neonates, but glomerulogenesis ceases after 40 days. Moreover, it is further inhibited by RF. Compensatory mechanisms in longer surviving preterm infants include glomerular hypertrophy and mesangial proliferation that could lead to hyperfiltration. 相似文献
34.
Aberrant p16 methylation is a biomarker for tobacco exposure in cervical squamous cell carcinogenesis 总被引:2,自引:0,他引:2
Lea JS Coleman R Kurien A Schorge JO Miller DS Minna JD Muller CY 《American journal of obstetrics and gynecology》2004,190(3):674-679
OBJECTIVE: The purpose of this study was to determine the association between active tobacco exposure and aberrant p16 promoter methylation in primary cervical squamous cell cancer and high-grade squamous cervical dysplasia. STUDY DESIGN: p16 methylation-specific polymerase chain reaction was performed on DNA that was extracted from 60 cervical cancers, 30 high-grade dysplasia specimens, and 78 normal cervical cytologic specimens. Patient data were obtained by medical record review or were collected prospectively. RESULTS: Aberrant p16 methylation was significantly higher in squamous cell cervical cancers (61%) than in squamous high-grade dysplasia (20%) or normal cytologic specimens (7.5%). Approximately one half the women with squamous cancer and one half of the women with high-grade dysplasia were active smokers. Aberrant p16 methylation was associated with active tobacco use in patients with squamous carcinoma (odds ratio, 20.6; 95% CI, 3.6-118; P<.001) and high-grade dysplasia (odds ratio, 4.57; 95% CI, 1.63-12.78; P=.002). CONCLUSION: Aberrant p16 methylation is associated strongly with active tobacco use in squamous cell cervical cancers and high-grade dysplasia. 相似文献
35.
36.
Despite the benefits of exclusive breastfeeding for the health of mothers and children, its practice has markedly declined throughout the developing world. Mass media-communication programmes could play an important role in reversing this trend. This study evaluated the extent to which exposure to behaviour change communication (BCC) messages in the media determined recent improvements in exclusive breastfeeding knowledge and practices in areas targeted by the Delivery of Improved Services for Health (DISH) Project of Uganda. Data were drawn from the 1999 DISH Evaluation Survey. The survey collected information from representative samples of women and men of reproductive age. Multiple logistic regressions were used for assessing the independent influences of BCC exposure on breastfeeding knowledge and practices, controlling for several confounding factors. The results indicated that the exposure to BCC messages was strongly associated with women's knowledge of six months as the ideal duration for exclusive breastfeeding. Positive influences on knowledge of men were also found. Media effects on women's current practice of exclusively breastfeeding their infants up to six months were less conclusive, possibly because of the short interval between the launch of the BCC campaign and survey implementation. While there was some evidence of bias of self-reported exposure, results of exploratory analysis of the indirect effects of communication campaigns suggest that impacts may be compounded as overall awareness is increased at the community level eventually leading to improved knowledge among individuals. 相似文献
37.
Opinion statement Cervical adenocarcinomas are increasing in incidence each year, comprising up to 25% of all cervical cancers diagnosed in
the United States. This increase largely reflects the inherent difficulty in detecting glandular precursor lesions using current
screening practices. However, there also appears to be a recent shift in the epidemiology of the disease process with younger
women being diagnosed more frequently. Fertility-sparing surgery is an option for selected patients with adenocarcinoma in
situ or stage IA1 cervical adenocarcinoma. Simple hysterectomy should be performed at the completion of childbearing or when preserving fertility
is not an issue. The treatment of choice for most women with stage IA2 to IB1 disease is radical hysterectomy. Fewer than 20% of patients will need adjuvant therapy and the cure rate is excellent. Primary
radiation with weekly cisplatin may be the best option for patients with stage IB2 to IIA cervical adenocarcinoma. Patients treated initially by primary radical surgery will almost certainly require postoperative
chemoradiation because of high-risk surgical-pathologic features. Patients with stage IIB to IVA disease should also receive
primary radiation with weekly cisplatin. Management of recurrence should be individualized, depending on the location of disease
and the type of previous therapy. 相似文献
38.
39.
Messer WB Vitarana UT Sivananthan K Elvtigala J Preethimala LD Ramesh R Withana N Gubler DJ De Silva AM 《The American journal of tropical medicine and hygiene》2002,66(6):765-773
Before 1989, dengue epidemiology in Sri Lanka was characterized by frequent transmission of all four dengue serotypes but a low incidence of dengue hemorrhagic fever (DHF). After 1989, cases of DHF dramatically increased. Here we present the results of epidemiologic studies conducted in Colombo, Sri Lanka before and after epidemic emergence of DHF in 1989. We compared the proportion of dengue cases among people with fever attending clinics from 1980 to 1984 and in 1997 and 1998 to determine if an increase in dengue transmission was associated with more DHF cases being reported. We also compared the relative distribution of dengue virus serotypes circulating in Colombo before and after the emergence of DHF. We detected no significant differences in dengue as a proportion of fever cases or in serotype distribution between the pre and post-DHF periods. We conclude that an increase in virus transmission or a change in circulating serotypes does not explain the epidemic emergence of DHF in Sri Lanka. 相似文献
40.