Pervasive developmental disorder and childhood-onset schizophrenia: comorbid disorder or a phenotypic variant of a very early onset illness?

BACKGROUND: Childhood-onset schizophrenia (COS) is a severe form of the adult-onset disorder with a high rate of premorbid developmental abnormalities. Early symptoms of pervasive developmental disorder (PDD) have been reported in five independent studies of COS. In this study, we compared evidence for premorbid PDD as a nonspecific manifestation of impaired neurodevelopment seen in schizophrenia, or as an independent risk factor for COS. METHODS: Diagnosis of past or current autism or PDD was made according to the DSM-IV criteria. COS patients with and without PDD were compared with respect to neuropsychological, clinical, and neurobiological measures. Several candidate genes for autism were examined in the entire COS sample and the subgroup with PDD using the Transmission Disequilibrium Test (TDT) and Quantitative TDT (QTDT). RESULTS: Nineteen (25%) of COS probands had a lifetime diagnosis of PDD: one met criteria for autism, two for Asperger's disorder, and 16 for PDD not otherwise specified. Premorbid social impairment was most common feature for COS-PDD subjects. The PDD group did not differ from the rest of the COS sample with respect to age of onset, IQ, response to medications, and rate of familial schizotypy. Unexpectedly, two siblings of COS-PDD probands met criteria for nuclear autism. There was no difference between PDD and non-PDD groups with respect to initial brain magnetic resonance imaging (MRI) measures. However, rate of gray matter loss was greater for PDD (n = 12) than for the non-PDD (n = 27) subgroup (-19.5 +/- 11.3 mL/year vs. -9.6 +/- 15.3 mL/year; p =.05). None of eight candidate genes for autism were associated with COS or COS-PDD. CONCLUSIONS: Premorbid PDD in COS is more likely to be a nonspecific marker of severe early abnormal neurodevelopment. However, the occurrence of two siblings of COS-PDD probands (17%) with nuclear autism remains to be understood.     

Bacteroides fragilis strains express multiple capsular polysaccharides.

Previous studies by our group have demonstrated that the capsule of Bacteroides fragilis type strain NCTC 9343 consists of two chemically distinct polysaccharides, designated PS A and PS B. These polysaccharides can be isolated as an aggregate from the surface of the organism and give a complex multiprecipitin profile when they are reacted with homologous antiserum in an immunoelectrophoresis assay. Following structural analysis of PS A and PS B, we have determined that the complex precipitin profile is formed as a result of the differing electrophoretic and antigenic properties associated with each of these polymers. Presently, we have examined the capsular polysaccharides of 13 other strains of B. fragilis according to methods used for the prototype strain. The capsules of these strains were extracted, partially purified, and analyzed by immunoelectrophoresis at pH 7.3. Following reaction with homologous polyclonal antisera, each of the capsular preparations tested yielded a complex precipitin profile similar to that of the prototype strain. When reacted by immunoelectrophoresis with polyclonal antiserum to 9343 or with monoclonal antibodies to PS A and PS B, these capsular preparations appeared to be antigenically diverse; some preparations (50%) showed complete or partial cross-reaction. These results suggest that the dual polysaccharide motif seen with the prototype strain is a common feature of B. fragilis strains. In addition, the antigenic heterogeneity of B. fragilis capsular polysaccharides could be used for the development of a serological typing scheme.     

Intraspecific variation in the distribution of the interstitial telomeric (TTAGGG)n sequences in Micoureus demerarae (Marsupialia: Didelphidae)

The distribution of the telomeric sequence (TTAGGG)_n was studied in chromosomes of Micoureus demerarae (2n=14), a South American marsupial, by fluorescence in-situ hybridization (FISH). The telomeric repeat sequence was present at both ends of all chromosomes, but also various interstitial telomeric sequences (ITS) were detected in the pericentromeric heterochromatic regions. Intraspecific differences in the number of ITS (2 to 8) were observed without intraindividual variation. The presence of telomere-like sequences in the same regions of constitutive heterochromatin suggest that these segments are not necessarily remnants of true telomeres resulting from chromosome rearrangements but could be part of the satellite DNA.     

Recombinant human thyrotropin stimulation of fluoro-D-glucose positron emission tomography uptake in well-differentiated thyroid carcinoma

TSH stimulates thyrocyte metabolism, glucose transport, and glycolysis. 2-Deoxy-2-[18F]fluoro-D-glucose (FDG) is a glucose analog used in positron emission tomography (PET) to detect occult well-differentiated thyroid carcinoma. The objective of this study was to examine the effects of recombinant human TSH (rTSH) on FDG PET uptake in patients with residual or recurrent disease. Seven patients with well-differentiated thyroid carcinoma, negative 131-I scintigraphy, and biochemical evidence of residual disease were randomized and prospectively studied with FDG PET both on thyroid hormone suppression and rTSH stimulation within 1 wk. All lesions seen on the TSH suppression scans were seen on the rTSH stimulation studies. rTSH stimulation studies identified four additional lesions not seen on TSH suppression. One patient was positive on rTSH stimulation alone. The mean (2.54 +/- 0.72 vs. 1.79 +/- 0.88) and maximum (2.49 +/- 0.95 vs. 1.74 +/- 0.81) lesion to background ratios were significantly higher with rTSH stimulation, compared with TSH suppression (P = 0.02 for both). rTSH stimulation improves the detectability of occult thyroid metastases with FDG PET, compared with scans performed on TSH suppression.     

指南2.0:为成功制定指南而系统研发的全面清单

背景虽然当前已有一些评估卫生保健指南可靠性的工具,但仍缺乏针对制定指南实际步骤的指导。针对指南制定者们所需考虑的相关资源和工具,我们系统研发了一份全面的条目清单,但这并不意味着每篇指南都需遵守该清单的所有条目。方法我们检索了国际指南制定机构的指南制定手册、指南的指南(主要是来自国际和国家机构以及专业学会的方法学报告),以及提供系统指导的最新文章。经过反复评价这些资料,尽可能全面地罗列和提取条目,并制定与指南有关的重要主题。通过反复讨论,我们对条目进行评价以去重和补漏,同时邀请指南制定专家对所增加的条目进行修改并提出建议。结果我们制定了一份包含18个主题、146个条目的清单,并建立了帮助指南制定者应用这些条目的网站。这些主题和条目涵盖了指南从规划、完成、实施和评估的全过程。最终的清单版本也包括了培训所需的资料以及应用这些条目时用到的方法学参考文献的链接。解释本清单将提供给指南制定者用作参考。仔细考虑清单中的条目将有助于指南的制定、实施和评估,我们也将会通过大众反馈来修订并持续更新清单。     

Psychometric testing of the self-care of heart failure index

BACKGROUND: Self-care is believed to improve outcomes in heart failure (HF) patients. However, research testing this assumption is hampered by difficulties in measuring self-care. The purpose of this study was to evaluate the psychometric properties of a revised instrument measuring self-care in persons with HF, the Self-Care of Heart Failure Index (SCHFI). The SCHFI is a self-report measure comprised of 15 items rated on a 4-point response scale and divided into 3 subscales. METHODS AND RESULTS: Psychometric testing was done using data from 760 HF patients (age 70.36 +/- 12.3 years, 51% male) from 7 sites in the United States. Reliability of the SCHFI (alpha.76) was adequate. Reliability of the Self-Care Maintenance subscale was lower than desired (alpha.56) but the reliability of the other subscales was adequate: Self-Care Management (alpha.70) and Self-Care Self-Confidence (alpha.82). Construct validity was supported with satisfactory model fit on confirmatory factor analysis (NFI=.69, CFI.73). Construct validity was supported further with significant total and subscale (all P <.05) differences between patients experienced with HF and those newly diagnosed, consistent with the underlying theory. CONCLUSION: Low reliability of the Self-Care Maintenance subscale was expected because the items reflect behaviors known to vary in individuals. The reliability and validity of the SCHFI are sufficient to support its use in clinical research.