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1.
BACKGROUND: Exclusive breastfeeding for the first 6 months is recommended by the World Health Organization and considered allergy preventive. However, it is not known whether prolonging exclusive breastfeeding for over 6 months provides further benefit in allergy prevention. OBJECTIVE: The aim of this prospective 20-year follow-up study was to find out whether the allergy protective effect can be enhanced by prolonging strictly exclusive breastfeeding for > or =9 months of age. A total of 200 unselected healthy newborns were enrolled in the study. Their mothers were encouraged to maintain exclusive breastfeeding for as long as possible. The number of infants on strictly exclusive breastfeeding was 167 at 2, 116 at 6, 36 at 9 and 7 at 12 months of age. Of the 200 infants, 42% had a family history of allergy. The children were re-assessed at ages 5 (n=163), 11 (n=150) and 20 years (n=164) with clinical examination, skin prick testing, and parental and personal structured interviews. RESULTS: Exclusive breastfeeding prolonged for > or =9 months was associated with atopic dermatitis (P=0.002) and symptoms of food hypersensitivity (P=0.02) at age 5 years, and with symptoms of food hypersensitivity at age 11 years (P=0.01), in children with a family history of allergy. CONCLUSION: Prolonging strictly exclusive breastfeeding for > or =9 months was not helpful in atopy prevention, instead, it was associated with increased atopic dermatitis and food hypersensitivity symptoms in childhood.  相似文献   
2.
The presence of human papillomavirus (HPV) DNA in cervical and vaginal scrapes was analyzed by the AffiProbe HPV test kit (Orion Corp., Orion Pharmaceutica, Helsinki, Finland), which is a 1-day solution hybridization test for HPV type 6/11, 16, or 18. The AffiProbe test was compared with a commercially available dot blot test (ViraPap and ViraType tests; Life Technologies Inc., Gaithersburg, Md.). The study group consisted of 178 patients seen in a gynecological outpatient clinic. Altogether, 64 specimens (36 cervical and 28 vaginal scrapes) from 49 patients were positive by the AffiProbe test. Concurrently collected cervical scrapes from 174 patients were available for the reference test, which yielded 27 positive results for HPV type 6/11 or 16/18 and 25 positive results for HPV type 31/33/35. Agreement as to the presence of HPV type 6/11, 16, or 18 by the two tests was reached in 85% of the specimens. Eleven cervical specimens were positive by the AffiProbe test only, and nine cervical specimens were positive by the ViraType test only. Independent evidence obtained by the polymerase chain reaction, repeat examination, or the concurrent presence of HPV DNA in vaginal or vulval epithelium supported the AffiProbe and the ViraType test results for 6 of the 11 and 6 of the 9 specimens with discrepant results, respectively. Thus, the DNA tests had similar sensitivities for HPV type 6/11, 16, and 18 DNAs, but the results were obtained within 1 day by the AffiProbe test, whereas results for the ViraPap and ViraType analyses required from 4 days to 2 weeks.  相似文献   
3.
The opening of sarcolemmal K(ATP) channels is considered to be an important endogenous cardioprotective mechanism. On the other hand, age-dependent changes in the myocardial susceptibility to ischemia and hypoxia have been observed in different species, including humans. Here, we have hypothesized that aging might be associated with the changes in sarcolemmal K(ATP) channels. Therefore, the main objective of the present study was to establish whether aging changes expression of cardiac sarcolemmal ATP-sensitive K+ (K(ATP)) channels. RT-PCR using primers specific for K(ATP) channel subunits, Kir6.2, Kir6.1 and SUR2A subunits was performed using total RNA from guinea-pig ventricular tissue. Whole cell electrophysiology was done on isolated guinea-pig ventricular cardiomyocytes. Western blotting using anti-Kir6.2 and anti-SUR2A antibodies was performed on cardiac membrane fraction. Tissue and cells were harvested from young and old, male and female guinea-pigs. RT-PCR analysis did not reveal significant age-related changes in levels of Kir6.1 or Kir6.2 mRNAs. However, levels of SUR2A were significantly lower in old than in young females. Such age-differences were not observed with cardiac tissue from male animals. In both old and young males, pinacidil (100 microM) induced outward currents. The difference between current density of pinacidil-sensitive component in females, but not males, was statistically significant. Western blotting analysis revealed higher levels of Kir6.2 and SUR2A proteins in cardiac membrane fraction from young than old females. The present study demonstrates that in females, but not males, aging is associated with decrease in number of cardiac K(ATP) channels which is due to decrease in levels of the SUR2A subunit.  相似文献   
4.
BACKGROUND: We report data on 1-year prevalence and comorbidity of depression, related impairment, treatment need, and psychiatric treatment among young adults. METHODS: A sample of young urban adults (n=245) mean age 21.8 years was screened from a baseline population of 706 high-school students and given a semistructured clinical interview to evaluate 12-month prevalence of depression, psychosocial functioning according to DSM-IV GAF scale, need for psychiatric treatment, and use of mental health services. RESULTS: One in 10 young adults suffered from depression with associated psychosocial impairment, the female-to-male-ratio being approximately 2:1. Most depressive disorders were comorbid with other DSM-IV disorders, depression usually occurring secondary to other disorders. Comorbidity was related to impairment, treatment need, and treatment contacts. Less than half of the depressed young adults had ever contacted mental health services, and less than one-third reported treatment contacts during the index episode. Males were less likely than females to report previous treatment contacts or intention to refer to mental health services for their problems, but treatment contacts during the index episode were reported equally often by both sexes. CONCLUSIONS: A minority of the severely depressed young adults with associated impairment had sought treatment. Except for subjects with dysthymia, no gender difference emerged in treatment contact rates during the 12-month depression episode. Comorbidity showed important clinical implications by its relation to severity of depression and treatment contacts.  相似文献   
5.
Sequential serum samples, collected over a 2-3 year follow-up period, of 28 HIV-infected individuals were tested for the presence of neutralizing antibodies against one HIV isolate, HTLV-IIIB, and titrated, by Western blotting, against different HTLV-III specific proteins. Neutralizing antibodies were found in 66% of the samples tested and highest neutralization titres observed in cases with lymphadenopathy syndrome. Antibody titres against the viral proteins also seemed to be highest in cases with LAS. Neutralization titres correlated well with antibodies to envelope glycoproteins gp41 and gp120 and to one of the core proteins, p17. An increase in neutralization titre during the follow-up period was associated with a stable clinical course. Furthermore, the occurrence of antibodies directed against the external envelope glycoprotein (gp120) in the initial serum sample correlated well with a stable clinical course. The results suggest that neutralizing activity in the serum, particularly that evoked against gp120, may have some prognostic significance, and that several distinct antigenic epitopes on the virus may be a target for neutralizing antibodies.  相似文献   
6.
Summary Information concerning the expression kinetics and subcellular localization of HIV regulatory proteins is of importance in understanding the viral pathogenesis and may be relevant for drug and vaccine development, as well. We have used combined immunocytochemistry and in situ hybridization to study firstly, the order of expression of regulatory HIV-1 proteins Nef, Rev and Tat in relation to non-spliced and spliced mRNA expression and secondly, the subcellular localization of these proteins in acutely and chronically infected human T-cell lines. We used monoclonal antibodies against HIV-1 Nef, Tat, Rev and gp160, and RNA probes reacting either with all mRNAs (nef) or only with the full-length mRNA (gag-pol). In acutely infected MT-4 and H9 cells, four distinct phases of infection could be defined. In the first phase lasting from 0 to 6 h post-infection, only incoming virus could be demonstrated by gp160 immunocytochemistry. During the second, regulatory phase (6–9 h), abundant cytoplasmic expression of Nef, Rev and Tat proteins and a positive in situ RNA hybridization with the nef probe was seen, while the in situ hybridization with full-length mRNA probe and immunohistochemistry for gp160 were still negative. The productive phase (12–48 h) was characterized by abundant expression of full-length mRNA and gp160, and by the nuclear localization of Nef and Tat proteins. In contrast, an antibody that recognized the RRE binding region of the Rev protein localized Rev in the cytoplasm both during the regulatory and productive phase. During the fourth, cytopathic phase, the expression of mRNA or viral proteins decreased and the regulatory proteins studied were again mainly localized in the cytoplasm. Based on the results, we speculate that HIV Nef may function as a nuclear factor, and that Tat is possibly bound by cellular proteins before its transport to the nucleus.  相似文献   
7.
A cytomegalovirus (CMV)-specific sandwich hybridization test was constructed by using two adjacent BamHI DNA fragments of CMV DNA as reagents. The fragments were cloned into two different vectors. One of the recombinants was attached to the filter, and the other was the labeled probe. When present in the sample, CMV DNA mediated labeling of the filter by hybridizing to both the filter-bound DNA and the probe. The sandwich hybridization test was applied for the detection of CMV DNA from urine. DNA was released from virus by 2% Sarkosyl, concentrated by 2-butanol extraction and isopropanol precipitation, denatured, and finally subjected to the sandwich hybridization test. As a result, 70 to 90% of the original viral DNA could be recovered and demonstrated by the quantitative hybridization reaction. Urine could be stored at room temperature in Sarkosyl for at least 2 days without affecting the detectability of CMV. The clinical applicability of the test was evaluated by studying urine samples from four infants excreting CMV. Sandwich hybridization demonstrated the presence of CMV DNA in all of the specimens. These contained originally 10(5) to 10(8) CMV DNA molecules per ml.  相似文献   
8.
Objective: The aim of this study was to evaluate and compare the efficacy of punch biopsies and cervical scrapes in the detection of human papillomavirus (HPV) DNA from the cervix and compare the results with the histopathologic diagnosis.Methods: The specimens were collected simultaneously, and HPV DNA was detected using a liquid hybridization test.Results: Biopsies and scrapes were equally efficient, but each detected only two-thirds of all HPV-DNA-positive patients. Thus, the positivity rate increased when both tests were used. Overall, 13% of patients with normal histopathology, 38% of patients with benign atypia, and 66% of patients with squamous intraepithelial lesions (SIL) were HPV-DNA positive. HPV-DNA 16 was found in 54% of HPV-DNA-positive patients with SIL, in 20% of HPV-DNA-positive patients with atypia, and in none of patients with normal histopathology.Conclusions: The liquid hybridization test used in this study detects HPV DNA equally efficiently from both biopsies and scrapes. The test can be performed in 1 working day. However, the sensitivity of the test is low, and it only detects a limited number of HPV types.  相似文献   
9.
OBJECTIVE: HIV accessory protein Nef is expressed early in the infectious cycle of the virus and has been shown to be an effective immunogen in humoral and cellular immune responses. We have used two different self-replicating pBN vectors and one non-replicating pCGal2 derived (pCG) vector expressing HIV-1 Nef in DNA immunisation of mice in order to determine their efficiency in raising humoral and cellular immune responses. DESIGN AND METHODS: The expression of Nef by the three plasmids was tested by transfections into COS-1 cells. Balb/c mice were immunised with the pBN-NEF and pCGE2-NEF constructs using gold particle bombardment. Immunoblotting and immunocytochemistry were used to detect in vitro expression of Nef. 51Cr release assay, ELISA and immunoblotting were used to detect cellular and humoral immune responses in immunised mice. RESULTS: Efficient in vitro expression of Nef was detected in pBN and pCGE2-NEF transfected cells, in pBN-NEF transfected cells the expression lasting up to three weeks. Anti-Nef antibodies in sera of 13 of 16 pBN-NEF immunised mice were detected within four weeks after the last immunisation, whereas only 2 of 12 pCGE2-NEF immunised mice had very weak anti-Nef antibodies. Twelve of the pBN-NEF immunised mice (75%) and 6 the pCGE2-NEF immunised mice (50%) showed Nef-specific cytotoxic T lymphocyte (CTL) responses within four weeks. CONCLUSIONS: We conclude that the three eukaryotic expression vectors tested are capable of inducing a cell mediated immune response towards HIV-1 Nef and should be considered as part of a genetic HIV vaccine.  相似文献   
10.
Aims   To investigate whether substance use disorders (SUDs) are associated with verbal intellectual ability, psychomotor processing speed, verbal and visual working memory, executive function and verbal learning in young adults, and to study the associations of SUD characteristics with cognitive performance.
Participants   A population-based sample ( n  = 466) of young Finnish adults aged 21–35 years.
Measurements   Diagnostic assessment was based on all available information from a structured psychiatric interview (SCID-I) and in- and out-patient medical records. Established neuropsychological tests were used in the cognitive assessment. Confounding factors included in the analyses were comorbid psychiatric disorders and risk factors for SUDs, representing behavioural and affective factors, parental factors, early initiation of substance use and education-related factors.
Findings   Adjusted for age and gender, life-time DSM-IV SUD was associated with poorer verbal intellectual ability, as measured with the Wechsler Adult Intelligence Scale–Revised (WAIS-R) vocabulary subtest, and slower psychomotor processing, as measured with the WAIS-R digit symbol subtest. Poorer verbal intellectual ability was accounted for by parental and own low basic education, whereas the association with slower psychomotor processing remained after adjustment for SUD risk factors. Poorer verbal intellectual ability was related to substance abuse rather than dependence. Other SUD characteristics were not associated with cognition.
Conclusions   Poorer verbal intellectual ability and less efficient psychomotor processing are associated with life-time alcohol and other substance use disorders in young adulthood. Poorer verbal intellectual ability seems to be related to parental and own low basic education, whereas slower psychomotor processing is associated with SUD independently of risk factors.  相似文献   
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