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1.
Xylocandin is a complex of novel peptides with potent antifungal activity that is produced by Pseudomonas cepacia ATCC 39277. The complex was isolated from the fermentation broth by extraction with butanol-methanol, 9:1, followed by collection of the precipitate formed upon concentration of the solvent extract. Purification was effected by chromatography on reversed phase and size exclusion gels followed by TLC on silica gel. These techniques afforded eight components: A1, A2, B1, B2, C1, C2, D1 and D2. A mixture of the two closely related components, xylocandins A1 and A2, displayed potent anticandidal and antidermatophytic activities in vitro. The activity was diminished by the presence of serum or vaginal washings. No antibacterial activity was demonstrable.  相似文献   
2.
Using a silver staining technique, argyrophilic nucleolar organiser region-associated proteins (AgNORs) have been studied in routinely processed paraffin sections of 46 invasive malignant melanomas (MM) of the conjunctiva. The aim of this retrospective study was to assess the value of the AgNOR method as a prognostic indicator for this neoplasm. The 46 cases were divided into two groups: (A) 14 cases of MM that metastasised and caused death of the patient within 5 years of (histological) diagnosis, and (B) 32 cases of MM that did not metastasise and in which patients survived beyond 5 years. The mean of the AgNOR counts per nucleus was 7.03 (95% CI: 5.81-8.24) in group A, and 7.15 (95% CI: 6.53-7.77) in group B. A comparison using a multifactor analysis of variance (ANOVA) model, which corrected for possible confounding effect of tumour thickness, site, and cell type showed no significant difference in AgNOR counts between groups A and B (p = 0.8). Analysis by the Cox proportional hazards regression model showed that survival was not influenced significantly by the mean AgNOR number (hazard ratio: 0.92). Whereas the AgNOR technique may be used to distinguish benign from malignant melanocytic lesions of the conjunctiva, we conclude it has no value in predicting the outcome for patients with conjunctival MM.  相似文献   
3.
BACKGROUND: Prepulse inhibition (PPI) is an operational measure of sensorimotor gating and is impaired in a family of neuropsychiatric disorders characterized by abnormalities of inhibitory function. Adults with autistic disorder (AD) exhibit clinical features of inhibitory deficits, such as restrictive and repetitive behaviors, that may be explained by deficits in sensorimotor gating. METHODS: Acoustic startle reactivity, habituation, and PPI (30-, 60-, 120-msec interstimulus intervals) were assessed in 14 adult men diagnosed with AD and 16 typically developing normal comparison (NC) participants. All participants were administered measures of intelligence and frontal-executive functioning. RESULTS: Adults with AD exhibited significantly less PPI in the 60-msec condition than NC participants, which was correlated with increased ratings of restricted and repetitive behaviors. The groups did not differ on measures of startle amplitude or overall habituation. There was, however, a significant group-by-block habituation effect. Furthermore, PPI was not related to intelligence but was moderately associated with performance on a measure of frontal-executive functioning. CONCLUSIONS: Adults with AD have sensorimotor gating deficits similar to other neurodevelopmental disorders, implicating a failure of normal inhibitory regulation of sensory, motor, and attentional mechanisms. Thus, PPI deficits may be indirectly linked to one of the hallmark features of AD.  相似文献   
4.
Lafora disease (LD) is a fatal and the most common form of adolescent-onset progressive epilepsy. Fulminant endoplasmic reticulum (ER)-associated depositions of starch-like long-stranded, poorly branched glycogen molecules [known as polyglucosans, which accumulate to form Lafora bodies (LBs)] are seen in neuronal perikarya and dendrites, liver, skeletal muscle and heart. The disease is caused by loss of function of the laforin dual-specificity phosphatase or the malin E3 ubiquitin ligase. Towards understanding the pathogenesis of polyglucosans in LD, we generated a transgenic mouse overexpressing inactivated laforin to trap normal laforin's unknown substrate. The trap was successful and LBs formed in liver, muscle, neuronal perikarya and dendrites. Using immunogold electron microscopy, we show that laforin is found in close proximity to the ER surrounding the polyglucosan accumulations. In neurons, it compartmentalizes to perikaryon and dendrites and not to axons. Importantly, it binds polyglucosans, establishing for the first time a direct association between the disease-defining storage product and disease protein. It preferentially binds polyglucosans over glycogen in vivo and starch over glycogen in vitro, suggesting that laforin's role begins after the appearance of polyglucosans and that the laforin pathway is involved in monitoring for and then preventing the formation of polyglucosans. In addition, we show that the laforin interacting protein, EPM2AIP1, also localizes on the polyglucosan masses, and we confirm laforin's intense binding to LBs in human LD biopsy material.  相似文献   
5.
Rh incompatibility disease (ie Rh hemolytic disease of the fetus and newborn) has been implicated as a risk factor for schizophrenia. Here, we extend the maternal-fetal genotype incompatibility (MFG) test used in an earlier case-parent trio study that found significant evidence for an increased risk of schizophrenia in RHD MFG-incompatible children. We modify the MFG test for case-parent trios to include any number of siblings. This modified test enables us to use more of the available data from the earlier study. The increased sample size not only gives us greater power to test for MFG incompatibility but it also enables us to model the impact of previous RHD MFG-incompatible pregnancies on the relative risk of RHD MFG incompatibility in later-born siblings. This modeling is important, because RHD MFG incompatibility is a proxy for Rh incompatibility disease, and the risk of Rh incompatibility disease increases with the number of previous RHD MFG-incompatible pregnancies. The best-fitting models are consistent with the hypothesized effect that previous incompatible pregnancies increase the risk of schizophrenia due to RHD MFG incompatibility. There was significant evidence that the relative risk of schizophrenia in the second- and later-born RHD MFG-incompatible children is 1.7, consistent with earlier estimates. Our extension of the MFG test has general application to family-based studies of maternal-genotype and MFG interaction effects.  相似文献   
6.
AIMS/METHODS: A national data collection exercise was carried out in more than 100 hospital eye service units within the UK to provide clinical and administrative information on patients undergoing cataract surgery. This included patient clinical data such as visual acuity at the time of wait listing and at the time of admission for surgery, presence of other eye disorders, other serious medical disorders, and data on waiting time and type of admission. RESULTS: The profiles of the 18 454 patients aged 50 years or older are reported. Findings of particular note were as follows. At the time of wait listing for cataract surgery 31% had visual acuity of 6/12 or better, 54% had visual acuity between 6/18 and 6/60, and 15% had less than 6/60 vision. Considering those who had visual acuity of 6/12 or better at the time of wait listing, by the time of admission for surgery, the vision deteriorated to 6/18-6/60 in 33% and in a further 3% the vision deteriorated to below 6/60. In patients with moderately poor visual acuity (<6/12-6/60) at the time of wait listing, 13% had less than 6/60 vision by the time of admission for surgery. CONCLUSION: This type of data collection and reporting exercise provides new material that can be used in the planning and provision of cataract surgery services in the UK.  相似文献   
7.
To identify disease-specific T cell changes that occur in Crohn's disease (CD), the T cell receptor BV repertoires of lamina propria lymphocytes (LPL) isolated from both the inflamed and "disease-inactive" colons of seven CD patients were compared by the quantitative PCR and DNA sequence analysis. It was observed that the BV repertoires of LPL isolated from the disease-active and disease-inactive parts of the colon from the same individual were very different. Furthermore, nearly all of the differences occurred in CD4+ LPL, with very few differences in the CD8+ population of LPL. Although the pattern of BV segments that was increased in disease-active tissue relative to disease-inactive tissue was different for all seven CD patients, there were several BV segments that increased uniformly in the disease-active tissue of all seven individuals. CDR3 length analysis and DNA sequencing of these BV segments revealed that in six of the seven CD patients there was a striking degree of oligoclonality that was absent from disease-inactive tissue of the same individual. These observations suggest that at least some of the inflammation in CD is the result of responses by CD4+ T cells to specific antigens. The isolation of such inflammation-specific CD4+ T cells may make it possible to identify the antigens that are responsible for the inflammatory process in CD and provide a better understanding of its pathogenesis.  相似文献   
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9.
The coronavirus disease 2019 pandemic presents unprecedented challenges for the health care system. The pressure on health care staff continues to intensify, accentuated by the confinement (lockdown) of the population and the unprecedented duration of this emergency. Separately and especially together, overwork, degraded conditions of care because of the never-ending emergency, and the risk of exposure to the virus can lead to acute psychological distress or signs of burnout.This original program was developed at Cochin Hospital in Paris, France to prevent these potentially dramatic psychological consequences, support the medical staff, and identify those most affected to offer them specific care. A program and a space for relaxation and support for hospital caregivers by hospital caregivers, the Port Royal Bulle (the Bubble) offers these workers help in decompression and relaxation. It combines a warm and caring welcome that promotes attention, listening, conversations, and exchanges as needed, empathetic support, and the ability to participate in soothing, relaxing, or low-impact physical activities. It takes care of caregivers. The Bubble is a program that is simple to set up and that appears to meet professionals' expectations. Making it permanent and enlarging its scale, as a complement to existing programs, might help to support health care personnel in their work.  相似文献   
10.
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