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991.
Is bacterial vaginosis a stronger risk factor for preterm birth when it is diagnosed earlier in gestation? 总被引:5,自引:0,他引:5
Klebanoff MA Hillier SL Nugent RP MacPherson CA Hauth JC Carey JC Harper M Wapner RJ Trout W Moawad A Leveno KJ Miodovnik M Sibai BM Vandorsten JP Dombrowski MP O'Sullivan MJ Varner M Langer O;National Institute of Child Health Human Development Maternal-Fetal Medicine Units Network 《American journal of obstetrics and gynecology》2005,192(2):470-477
OBJECTIVE: It is stated commonly that the earlier in pregnancy bacterial vaginosis is diagnosed, the greater is the increase in risk of preterm birth compared with women without bacterial vaginosis. However, this contention is based on small numbers of women. STUDY DESIGN: In this analysis of 12,937 women who were screened for bacterial vaginosis as part of a previously conducted clinical trial, the odds ratio of preterm birth (<7 weeks of gestation) for asymptomatic bacterial vaginosis-positive versus bacterial vaginosis-negative women was evaluated among women who were screened from 8 to 22 weeks of gestation. RESULTS: The odds ratio of preterm birth among bacterial vaginosis-positive versus bacterial vaginosis-negative women ranged from 1.1 to 1.6 and did not vary significantly according to the gestational age at which bacterial vaginosis was screened. The odds ratio for preterm birth did not vary significantly by gestational age at diagnosis when bacterial vaginosis was subdivided into Gram stain score 7 to 8 or 9 to 10. CONCLUSION: Although bacterial vaginosis was associated with an increased risk of preterm birth, the gestational age at which bacterial vaginosis was screened for and diagnosed did not influence the increase. 相似文献
992.
993.
994.
Synergistic effects of light-emitting probes and peptides for targeting and monitoring integrin expression 总被引:4,自引:0,他引:4 下载免费PDF全文
Achilefu S Bloch S Markiewicz MA Zhong T Ye Y Dorshow RB Chance B Liang K 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(22):7976-7981
Integrins mediate many biological processes, including tumor-induced angiogenesis and metastasis. The arginine-glycine-aspartic acid (RGD) peptide sequence is a common recognition motif by integrins in many proteins and small peptides. While evaluating a small library of RGD peptides for imaging alpha(V)beta(3) integrin (ABI)-positive tumor cell line (A549) by optical methods, we discovered that conjugating a presumably inactive linear hexapeptide GRDSPK with a near-infrared carbocyanine molecular probe (Cypate) yielded a previously undescribed bioactive ligand (Cyp-GRD) that targets ABI-positive tumors. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay with A549 cells showed that Cyp-GRD was not cytotoxic up to 100 muM in cell culture. The compound was internalized by cells, and this internalization was blocked by coincubation with a cyclic RGD peptide (cyclo[RGDfV], f is d-phenylalanine) that binds ABI with high affinity. In vivo, Cyp-GRD selectively accumulated in tumors relative to surrounding normal tissues. Blocking studies with cyclo[RGDfV] inhibited the in vivo uptake of Cyp-GRD, suggesting that both compounds target the same active site of the protein. A strong correlation between the Cyp-GRD peptide and mitochondrial NADH concentration suggests that the new molecule could also report on the metabolic status of cells ex vivo. Interestingly, neither a Cypate-labeled linear RGD peptide nor an (111)In-labeled DOTA-GRD conjugate was selectively retained in the tumor. These results clearly demonstrate the synergistic effects of Cypate and GRD peptide for molecular recognition of integrin expression and suggest the potential of using carbocyanines as optical scaffolds for designing biologically active molecules. 相似文献
995.
Elevated stress sensitivity in corticotropin-releasing factor receptor 2 deficient mice decreases maternal, but not intermale aggression 总被引:2,自引:0,他引:2
Maternal aggression is a form of aggression towards intruders by lactating females that is critical for defense of offspring. During lactation, fear and anxiety are reduced, the CNS is less responsive to the anxiogenic neuropeptide, corticotropin-releasing factor (CRF), and central injections of CRF inhibit maternal aggression. Together, these previous findings suggest that decreased CRF neurotransmission during lactation supports normal maternal aggression expression. Recent work indicates that mice deficient in CRF receptor 2 (CRFR2) display increased anxiety-like behaviors, have a hypersensitive stress response, and overproduce CRF. In this study, we examined both maternal and intermale aggression in wild-type (WT) and CRFR2-deficient mice. CRFR2-mutant mice exhibited significant deficits in maternal aggression on postpartum Day 4 relative to WT mice in terms of percentage displaying aggression, mean number of attacks, and mean time in aggressive encounters. However, time sniffing male intruder, pup retrieval, number of pups, and performance on the elevated plus maze were similar between genotypes. In contrast, intermale aggression did not differ between genotype in any measure on any of three consecutive test days. For neither form of aggression did sites of attacks on the intruder differ between genotype. Taken together, the results suggest that differences in stress sensitivity and the overproduction of CRF of the knockout (KO) mice specifically affects maternal, but not intermale aggression. 相似文献
996.
Abrahams S Goldstein LH Suckling J Ng V Simmons A Chitnis X Atkins L Williams SC Leigh PN 《Journal of neurology》2005,252(3):321-331
Cognitive dysfunction can occur in some patients with amyotrophic lateral sclerosis (ALS) who are not suffering from dementia. The most striking and consistent cognitive deficit has been found using tests of verbal fluency. ALS patients with verbal fluency deficits have shown functional imaging abnormalities predominantly in frontotemporal regions using positron emission tomography (PET). This study used automated volumetric voxel-based analysis of grey and white matter densities of structural magnetic resonance imaging (MRI) scans to explore the underlying pattern of structural cerebral change in nondemented ALS patients with verbal fluency deficits. Two groups of ALS patients, defined by the presence or absence of cognitive impairment on the basis of the Written Verbal Fluency Test (ALSi, cognitively impaired, n=11; ALSu, cognitively unimpaired n=12) were compared with healthy age matched controls (n=12). A comparison of the ALSi group with controls revealed significantly (p<0.002) reduced white matter volume in extensive motor and non-motor regions, including regions corresponding to frontotemporal association fibres. These patients demonstrated a corresponding cognitive profile of executive and memory dysfunction. Less extensive white matter reductions were revealed in the comparison of the ALSu and control groups in regions corresponding to frontal association fibres. White matter volumes were also found to correlate with performance on memory tests. There were no significant reductions in grey matter volume in the comparison of either patient group with controls. The structural white matter abnormalities in frontal and temporal regions revealed here may underlie the cognitive and functional imaging abnormalities previously reported in non-demented ALS patients. The results also suggest that extra-motor structural abnormalities may be present in ALS patients with no evidence of cognitive change. The findings support the hypothesis of a continuum of extra-motor cerebral and cognitive change in this disorder. 相似文献
997.
Caton CL Drake RE Hasin DS Dominguez B Shrout PE Samet S Schanzer B Schanzer WB 《Archives of general psychiatry》2005,62(2):137-145
CONTEXT: The distinction between a substance-induced psychosis and a primary psychotic disorder that co-occurs with the use of alcohol or other drugs is critical for understanding illness course and planning appropriate treatment, yet there has been little study and evaluation of the differences between these 2 diagnostic groups. OBJECTIVE: To identify key demographic, family, and clinical differences in substance-induced psychosis and primary psychotic disorders diagnosed according to DSM-IV criteria using a research diagnostic instrument for psychiatric and substance use comorbidity. DESIGN: Data on demographic, family, and clinical factors were gathered at baseline as part of a 3-year longitudinal study of early-phase psychosis and substance use comorbidity in New York, NY. SETTING: Psychiatric emergency department admissions. PARTICIPANTS: The study is based on a referred sample of 400 subjects interviewed at baseline. Participants had at least 1 psychotic symptom assessed during administration of the research protocol, had used alcohol and/or other drugs within the past 30 days, and had no psychiatric inpatient history before the past 6 months. Subject race included 43.5% black, 42.0% Hispanic, and 14.5% white or other. MAIN OUTCOME MEASURE: Psychotic disorders defined by the DSM-IV. RESULTS: Overall, 169 (44%) were diagnosed as having substance-induced psychosis and 217 (56%), as having primary psychosis. Significant differences were observed in all 3 domains. Multivariate analysis using logistic regression identified the following 3 key predictors as being greater in the substance-induced group: parental substance abuse (odds ratio [OR], 1.69; 95% confidence interval [CI], 1.00-2.85), a diagnosis of dependence on any drug (OR, 9.41; 95% CI, 5.26-16.85), and visual hallucinations (OR, 2.13; 95% CI, 1.10-4.13). The key predictor of total positive and negative symptom score was greater in the primary psychosis group (OR, 0.96; 95% CI, 0.94-0.97). CONCLUSIONS: Differences in demographic, family, and clinical domains confirm substance-induced and primary psychotic disorders as distinct entities. Key predictors could help emergency clinicians to correctly classify early-phase psychotic disorders that co-occur with substance use. 相似文献
998.
In aged cats, light microscopic studies revealed significant decrease in the soma size of choline acetyltransferase (ChAT)-positive neurons in the laterodorsal and pedunculo-pontine tegmental nuclei (LDT and PPT), compared with adult control animals. In addition, a significant reduction of the total dendritic length and total dendritic segment number of ChAT-positive neurons was detected in both the LDT and PPT of aged cats. However, in contrast to the changes of soma and dendrites, no significant changes in the number of ChAT-positive neurons in aged were found comparing to that in the control cats in both the LDT and PPT; nor were there differences in the staining intensity of the somata of neurons in the adult and aged cats. Electron microscopic analysis highlighted degenerative changes in cholinergic neurons in the LDT and PPT of aged cats which included somata with intracytoplasmic vacuoles, darkened mitochondria, depletion of dendritic microtubules and severe demyelination of axons. These data indicate that profound atrophic changes occur in cholinergic systems of the LDT and PPT as a consequence of the aging process. These alterations likely reflect the cellular bases for the age-related changes in REM sleep that occur in old animals. 相似文献
999.
Bialocerkowski AE Vladusic SL Howell SM 《Developmental medicine and child neurology》2005,47(8):563-570
This review aimed to synthesize current research evidence to determine the effectiveness of conservative interventions for infants with positional plagiocephaly. A systematic review was conducted, where papers were sourced from 13 library and internet databases. Research was included if published in English between 1983 and 2003. Level of evidence and quality of each paper was assessed to determine studies' magnitude of inherent bias. Results were synthesized in a narrative format and were considered with respect to homogeneity of participants, response rate, and outcome measures. Sixteen papers met inclusion criteria: 12 were case series and four were comparative studies. The methodological quality of the studies was moderate to poor, thus their results should be interpreted with caution. A consistent finding was that counterpositioning +/- physiotherapy or helmet therapy may reduce skull deformity; however, it was not possible to draw conclusions regarding the relative effectiveness of these interventions. Further investigation is required to compare the effect of helmet therapy with counterpositioning alone or when combined with physiotherapy. First, there is a need to develop an outcome measurement battery which incorporates psychometrically-sound measures from the perspectives of clinicians and patients. 相似文献
1000.
Daviss WB Perel JM Rudolph GR Axelson DA Gilchrist R Nuss S Birmaher B Brent DA 《Journal of the American Academy of Child and Adolescent Psychiatry》2005,44(4):349-357
OBJECTIVE: To examine the steady-state pharmacokinetic properties of bupropion sustained release (SR) and their potential developmental differences in youths. METHOD: Eleven boys and eight girls aged 11 to 17 years old were prescribed bupropion SR monotherapy for attention-deficit/hyperactivity disorder (n = 16) and/or depressive disorders (n = 16). Bupropion SR was given in morning doses of 100 mg/day (n = 11) or 200 mg/day (n = 8) for 14 days or less, with five subjects studied on both doses. All subjects had blood draws from an intravenous port every 1 to 3 hours for 24 hours after their usual morning doses. Pharmacokinetic variables were determined by noncompartmental and compartmental analyses for bupropion and metabolites, respectively. RESULTS: Bupropion and its metabolites exhibited linear pharmacokinetics. Areas under the concentration curves for the hydroxybupropion, threohydrobupropion, and erythrohydrobupropion were 20, 12, and 2.7 times higher, respectively, than for bupropion. Relative to adults, the mean half-lives of bupropion (12.1 hours) and threohydrobupropion (26.3 hours) were significantly shorter, and areas under the concentration curve ratios of metabolites to bupropion were 19% to 80% higher. CONCLUSIONS: Youths metabolize bupropion SR faster to hydroxybupropion and other active metabolites than adults. Until the clinical importance of bupropion's metabolites is clarified, bupropion SR should be given in divided doses to youths, as the manufacturer recommends for adults taking higher doses. 相似文献