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71.
AIMS: The occurrence of human granulocytic ehrlichiosis (HGE) in a patient with chronic myelogenous leukaemia (CML) provided an opportunity to study whether Anaplasma phagocytophilum, the aetiological agent of HGE, infects mature or immature cells, both in vivo and in vitro. METHODS: Diagnosis of HGE was confirmed by culture, polymerase chain reaction (PCR), detection of intragranulocytic inclusions, and serology. The infection rates of different myelogenous stages of granulocytic differentiation were determined by microscopy. Anaplasma phagocytophilum infection of the bone marrow was analysed by PCR, culture, and microscopy. In addition, the in vitro growth of A phagocytophilum in the patient's granulocytes and in HL-60 cells (a promyelocytic leukaemia cell line) was compared. RESULTS: Pretreatment blood smears showed that mature granulocytic cells had a higher infection rate with A phagocytophilum than did immature cells. In the original inoculation of the patient's cells into HL-60 cells to isolate A phagocytophilum, the bacterium grew faster in the patient's leukaemic cells than in HL-60 cells. Anaplasma phagocytophilum inclusions were rarely seen in bone marrow granulocytes and PCR was negative. In vitro, two A phagocytophilum isolates grew faster in the patient's granulocytes than in HL-60 cells. CONCLUSIONS: The superior growth in CML cells compared with HL-60 cells suggests that A phagocytophilum preferentially infects mature granulocytes. The higher infection rate of the patient's mature versus immature granulocytes before treatment and the minimal level of infection of the patient's bone marrow support this. It is possible that the primary site of infection in HGE is the peripheral mature granulocytic population.  相似文献   
72.
Congenital nephrogenic diabetes insipidus (NDI) is a rare disease caused most often by mutations in the vasopressin V2 receptor (AVPR2). We studied a family which included a female patient with NDI with symptoms dating from infancy. The patient responded to large doses of desmopressin (dDAVP) which decreased urine volume from 10 to 4 I/day. Neither the parents nor the three sisters were polyuric. The patient was found to be a compound heterozygote for two novel recessive point mutations in the aquaporin-2 (AQP2) gene: L22V in exon 1 and C181W in exon 3. Residue Cys181 in AQP2 is the site for inhibition of water permeation by mercurial compounds and is located near to the NPA motif conserved in all aquaporins. Osmotic water permeability (Pf) in Xenopus oocytes injected with cRNA encoding C181W-AQP2 was not increased over water control, while expression of L22V cRNA increased the Pf to approximately 60% of that for wild-type AQP2. Co-injection of the mutant cRNAs with the wild-type cRNA did not affect the function of the wild-type AQP2. Immunolocalization of AQP2-transfected CHO cells showed that the C181W mutant had an endoplasmic reticulum-like intracellular distribution, whereas L22V and wild-type AQP2 showed endosome and plasma membrane staining. Water permeability assays showed a high Pf in cells expressing wild-type and L22V AQP2. This study indicates that AQP2 mutations can confer partially responsive NDI.   相似文献   
73.
Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.   相似文献   
74.
Results of a clinical study involving 382 subjects using the injectable contraceptive Noristerat (norethisterone enanthate) is presented. The maximum number of acceptors were between 21-25 years of age and had been married for 6-10 years. 50% began their 1st injection within 1 year of the last childbirth. Continuation rates were very high and about 75% returned for their 2nd injection. Among the users, weight gain was seen more commonly than weight loss. There was no significant change in blood pressure. 52.2% reported a menstrual pattern which was within the acceptable range of normal, while only 12.7% had amenorrhea. 15% showed other types of menstrual disturbance. Only 1 woman in the series became pregnant. Menstrual abnormality was the most common cause for discontinuation among the 71 subjects available for interview.  相似文献   
75.
Obstructive jaundice was produced in rats by ligation and transection of bile duct outside the liver; the control group underwent laparotomy alone. Pancreatic wet weight, amylase, lipase, protein, DNA, RNA, RNA/DNA ratio, and weight/100 g DNA were significantly increased in jaundiced rats when compared to control rats. Histologic evaluation of pancreatic tissue obtained from jaundiced rats revealed the appearance of large or multiple nuclei in pancreatic acinar cells. Basal plasma levels of immunoreactive CCK were significantly increased in haundiced rats at two weeks and four weeks but, when compared to the levels obtained in laparotomized controls at those time intervals, CCK levels were not significantly different. In jaundiced rats, plasma immunoreactive gastrin was found to be significantly decreased at two and four weeks. Plasma gastrin levels were also found significantly decreased when the jaundiced group was compared with laparotomized control group. The results suggest that obstructive jaundice induced enlargement of the pancreas, probably due to hyperplasia and hypertrophy of pancreatic cells. Whether or not this phenomenon is related to changes in gastrin and CCK is not known.This work was presented in part at the 36th Kinki Section Meeting of Japanese Gastroenterological Association (January 1982) in Osaka, Japan; at the Annual Meeting of the Japanese Pancreatic Association (March 1982) in Hiroshima, Japan; and at the American Gastroenterological Association (May 1983) in Washington, D.C.; and appeared in abstract form inGastroenterology 84: 1095, 1983.  相似文献   
76.
Widely consumed daal (lentils) in Bangladesh are an ideal vehicle for iron (Fe) fortification; however, an acceptable portion size in meals needs to be determined to carry out a community feeding study in at-risk adolescent girls. A non-randomized crossover trial was conducted with n = 100 Bangladeshi girls (12.9 ± 2.0 years of age). Two recipes (thin and thick) and three portion sizes (25 g, 37.5 g, 50 g of raw lentil) of daal were served with 250 g of cooked white rice in a counter-balanced manner over 12 weeks. Each meal was fed to participants 5 days/week for two weeks. Ratings of hunger, satiety, and palatability were measured before and after each meal using Visual Analog Scales (VAS). The thick preparation in the 37.5 g portion (~200 g cooked) elicited higher VAS ratings of hunger, satiety, and palatability compared to all other meals. The 50 g portion of the thin preparation had VAS ratings similar to those of the 37.5 g thick preparation. Consuming the 37.5 g portion of fortified daal would provide 6.9 mg Fe/day to girls in a community-based effectiveness study. This would meet ~86% and ~46% of the Recommended Dietary Allowance (RDA) for Fe for girls aged 9–13 and 14–18 years, respectively.  相似文献   
77.
ObjectivesTo quantify the impact of mammography-based screening on the quality of life, disability-adjusted life years (DALYs) averted or quality-adjusted life years (QALYs) gained can be used. We aimed to assess whether the use of DALYs averted or QALYs gained will lead to different cost-effective screening strategies.MethodsUsing the microsimulation model MISCAN, we simulated different breast cancer screening strategies varying in starting age (starting at 45, 47, and 50 years), stopping age (stopping at 69, 72, and 74 years), and frequency (annual [A], biennial [B], combination of both [A + B], and triennial [T]). In total, we defined 24 different breast cancer screening strategies, including no screening as a reference strategy. We calculated incremental cost-effectiveness ratios (ICERs) and compared which strategies were on the efficiency frontiers for DALYs and QALYs.ResultsBreast cancer screening averted between 46.00 and 105.58 DALYs and gained between 28.69 and 64.50 QALYs per 1000 women. For DALYs there were 5 strategies on the efficiency frontier (T50-69, T50-74, T45-74, B45-74, and A45-74). The same strategies plus one (B45-72) were on the efficiency frontier for QALYs.ConclusionsUsing DALYs averted instead of QALYs gained to assess the effects on quality of life from breast cancer screening in the Dutch population yields differences in ICERs, but almost the same strategies were on the efficiency frontiers. Whether the choice in outcome measure leads to a difference in optimal policy depends on the cost-effectiveness threshold.  相似文献   
78.

This study aimed to determine the seroprevalence and determinants of hepatitis B virus (HBV) infection among university students in Bangladesh. This cross-sectional study was conducted among 614 students from five universities in central Bangladesh. Data were collected on demographic information, immunization history, medical and blood transfusion history through the face-to-face interview. Blood samples were collected and screened for anti-HBsAg using ELISA, HBsAg Rapid Test-cassette, and immune chromatographic test. The overall seroprevalence of HBV infection was 5.0%, and vaccination coverage was 19.2% among the participants. Students having a history of surgery (OR 11.004, 95% CI 3.211–37.707), blood transfusion (OR 5.651, 95% CI 0.965–33.068), being married (OR 4.776, 95% CI 1.508–15.127), and not being vaccinated (OR 9.825, 95% CI 1.130–85.367) were at higher risk of being infected by HBV. This study showed the endemicity of HBV infection among the Bangladeshi population. Marriage, surgical or blood transfusion history, not being vaccinated were the determinants of HBV infection within the study population. Public health initiatives for preventing HBV infection at the university levels should be envisaged.

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79.
For immunization to be effective in the long run as a major global disease control intervention it is important to provide good quality vaccination services. Studies carried out in three countries in Asia (Bangladesh, India, and the Philippines) and two countries in Africa (Ethiopia and Malawi), and reported on in this article, document the fact that parents are willing to invest considerable effort in having their children vaccinated; however, there are a number of serious shortcomings in the quality of the routine vaccination services and strains are apparent at the interface between the vaccination providers and the users. These shortcomings are detracting from the sustainability of routine vaccination programmes and are promoting the growth of pools of nonimmunized and partially immunized children. To safeguard the continued operation and to enhance the coverage of routine vaccination programmes it is crucial that these difficulties be addressed.  相似文献   
80.
Following intranasal inoculation of wild-type BHV-5 in rabbits, we studied the sequential transneuronal passage of the virus in the CNS by immunocytochemistry, histopathology, and virus isolation. At 4 and 6 days postinfection (d.p.i.), rabbits had no or mild neurological signs, and virus was isolated only from the olfactory bulbs. At 8 and 9 d.p.i., infected rabbits had severe neurological signs, and virus could be isolated from multiple regions of the brain segments. In these rabbits, high titers of virus were consistently present in the anterior and posterior cortices, including frontal, piriform/entorhinal, temporal, parietal, and occipital cortices, the hippocampus and the amygdala. Virus was isolated occasionally from the midbrain/diencephalon and pons/medulla. Virus was not isolated from the cerebellum and trigeminal ganglion of rabbits examined from 2-12 d.p.i. Immunocytochemistry revealed virus-specific antigens at 4 d.p.i. within the glomerular layer, external plexiform layer, and mitral cell layer of the main olfactory bulb. At 6 d.p.i., virus-specific antigens were also present within the inner granular layer of the main olfactory bulb. At 8 and 9 d.p.i., widespread BHV-5-specific staining occurred in the areas of the brain connected to the main olfactory bulb, including the frontal/cingulate cortex, anterior olfactory nucleus, lateral olfactory tubercle, piriform/entorhinal cortex, hippocampus, amygdala, dorsal raphe, and locus coeruleus. In the trigeminal ganglion, specific staining was detected within a few neurons at 2,4, 6, 8 d.p.i. However, further spread of the virus along the trigeminal pathway was not evident. These data indicate that BHV-5 replicates and spreads preferentially in the olfactory pathway following intranasal instillation and that this viral spread correlated with the severity of neurological symptoms and histopathological lesions.  相似文献   
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