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61.
Percutaneous umbilical blood samples (PUBS), obtained under ultrasound guidance, are used for prenatal diagnosis and management of hemolytic disease of the newborn (HDN) and other fetal disorders. Rapid testing at the time of sampling is vital to distinguish fetal from maternal blood. Blood typing was performed by slide technique in the treatment room during 38 procedures on 25 patients. Anti-I was used to test 50 presumed PUBS; venous I-positive maternal blood was tested in parallel. Because anti-I cannot detect fetal blood after umbilical vein transfusion (UVT) of I-positive donor blood, ABO and Rh blood typing reagents were used to test 29 samples when maternal and fetal or donor blood groups differed. Monoclonal reagents were used for optimal detection of weak AB antigens in fetal blood. Avid, chemically modified anti-D was used for Rh typing. Blood typing showed 27 (34%) of 79 samples to be maternal blood. Fetal blood was obtained in 8 of 10 cases investigated for fetal disorder and in 16 cases of potential HDN (anti-D, 5; -CD, 5; -cE, 2; -K, 2; -c; -E). The absence of HDN (antigen-negative fetus) was determined in 4 cases. UVT afforded live birth of 9 of 10 infants with HDN and was not indicated in two cases.  相似文献   
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Recent studies have linked infectious agents to schizophrenia. The largest number of studies has involved the analysis of Toxoplasma gondii; these studies were subjected to a meta-analysis. Published articles and abstracts were identified by searches of MEDLINE, Ovid, and Google Scholar; by a search of Chinese publications; through letters to researchers; and by visiting China. Published and unpublished controlled studies that used serological methods for measuring T. gondii antibodies to assess inpatients and/or outpatients diagnosed with schizophrenia were selected for analysis, and source documents were translated as needed. Forty-two studies carried out in 17 countries over 5 decades were identified; 23 of these (6 unpublished) met selection criteria. The combined odds ratio (OR) was 2.73 (95% confidence interval, 2.10 to 3.60; chi-square with 1 df 263; P < .000001). Seven studies that included only patients with first-episode schizophrenia (OR 2.54) did not differ significantly from 16 studies that included patients in all clinical phases (OR 2.79). The results suggest that individuals with schizophrenia have an increased prevalence of antibodies to T. gondii. This association is consistent with other epidemiological studies as well as with animal studies. Although the OR of 2.73 is modest, it exceeds that for genetic or other environmental factors identified to date and suggests that Toxoplasma is in some way associated with a large number of cases of schizophrenia. If an etiological association can be proven, it would have implications for the design of measures for the prevention and treatment of this disease.  相似文献   
64.
Multiple genome-wide expression studies of bipolar disorder have been published. However, a unified picture of the genomic basis for the disease has not yet emerged. Genes identified in one study often fail to be identified in other studies, prompting the question of whether microarray studies in the brain are inherently unreliable. To answer this question, we performed a meta-analysis of 12 microarray studies of bipolar disorder. These studies included >500 individual array samples, on a range of microarray platforms and brain regions. Although we confirmed that individual studies showed some differences in results, clear and striking regulation patterns emerged across the studies. These patterns were found at the individual gene level, at the functional level, and at the broader pathway level. The patterns were generally found to be reproducible across platform and region, and were highly statistically significant. We show that the seeming discordance between the studies was primarily a result of the following factors, which are also typical for other brain array studies: (1) Sample sizes were, in retrospect, too small; (2) criteria were at once too restrictive (generally focusing on fold changes >1.5) and too broad (generally using p<0.05 or p<0.01 as criteria for significance); and (3) statistical adjustments were not consistently applied for confounders. In addition to these general conclusions, we also summarize the primary biological findings of the meta-analysis, focusing on areas that confirm previous research and also on novel findings.  相似文献   
65.
Genetic factors that modulate the immune response have been implicated as risk factors for schizophrenia and cognitive impairment. We assessed the correlation between cognitive functioning and the LTA Cys13Arg polymorphism in 351 individuals with schizophrenia, 122 with bipolar disorder, and 160 controls. There was a significant association between cognitive functioning and the LTA Cys13Arg polymorphism within the schizophrenia (p<0.008) but not the other diagnostic groups. There was no association between cognitive functioning and the two other polymorphisms in the same gene complex. The LTA Cys13Arg polymorphism may represent a risk factor for cognitive impairment in individuals with schizophrenia.  相似文献   
66.
OBJECTIVES: We investigated the association between serum levels of C-reactive protein (CRP), a marker of inflammation, and the severity of psychopathology and cognitive impairment in schizophrenia. METHODS: We measured the levels of CRP in N=413 individuals with schizophrenia. Symptom severity was evaluated with the Positive and Negative Syndrome Scale (PANSS) and cognitive functioning with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). RESULTS: The individuals with CRP >or=5.0 mg/microl had significantly lower RBANS cognitive scores than those with CRP <5.0 mg/microl (F=8.07, p<.005). However the CRP groups did not differ in the severity of positive, negative, or general PANSS symptoms (all p>.2). CONCLUSIONS: Elevated serum levels of C-reactive protein in schizophrenia are associated with the severity of cognitive impairment but not of psychiatric symptoms. The long term consequences of elevated levels of CRP require further investigation.  相似文献   
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68.
Schizophrenia and rheumatoid arthritis share an impressive number of similarities. Both are chronic, relapsing diseases of unknown etiology. Both became prominent in the early 19th century and have prevalences of approximately 1% in North America and Europe. Both run in families, have pairwise concordance rates of approximately 30% among monozygotic twins, and are more common among individuals born in urban areas. For both diseases, studies have reported greater exposure to cats in childhood than in controls. Both diseases have been associated with similar class II HLA antigens. Both have also been suspected of having infectious etiology, with similar agents—retroviruses, herpesviruses including EBV, and Toxoplasma gondii—having been associated in some cases. Since there is also a well-documented inverse correlation between these two diseases, it is possible that they share a common infectious and/or immune etiology and that once a person gets one of the diseases then they are relatively immune to the other.  相似文献   
69.
Although the Nazi genocide of Jews during World War II is well known, the concurrent Nazi genocide of psychiatric patients is much less widely known. An attempt was made to estimate the number of individuals with schizophrenia who were sterilized and murdered by the Nazis and to assess the effect on the subsequent prevalence and incidence of this disease. It is estimated that between 220 000 and 269 500 individuals with schizophrenia were sterilized or killed. This total represents between 73% and 100% of all individuals with schizophrenia living in Germany between 1939 and 1945. Postwar studies of the prevalence of schizophrenia in Germany reported low rates, as expected. However, postwar rates of the incidence of schizophrenia in Germany were unexpectedly high. The Nazi genocide of psychiatric patients was the greatest criminal act in the history of psychiatry. It was also based on what are now known to be erroneous genetic theories and had no apparent long-term effect on the subsequent incidence of schizophrenia.  相似文献   
70.
We have developed a competitive enzyme immunoassay for the measurement of purified toxin A of Clostridium difficile. However, when we applied this assay to the detection of C. difficile toxin in stool specimens, we noted a high rate of nonspecific activity in fecal specimens which did not contain toxin. We found that the low specificity (26%) of the assay was due to the presence in stool specimens of interfering factors which desorbed the antigen coated on the solid-phase surface. These factors could be detected by measurement of the desorption of biotin-labeled proteins attached to the solid-phase surface. In addition, these interfering factors were partially inactivated by heating at 56 degrees C for 10 min and partially inhibited by phenylmethylsulfonyl fluoride (2 mM) or soybean trypsin inhibitor (10 mg/ml). These data suggested that the desorbing activity was due to proteolytic activity in the fecal specimens. Fetal calf serum (50%) was found to be the most effective measure in preventing the interfering effect. By using 50% fetal calf serum as a diluent, we increased the specificity of the antibody inhibition enzyme immunoassay to 93%. Interfering factors in stool specimens could be a cause of false-positive results in other competitive immunoassay systems. The use of diluents which neutralize protease activity can result in a marked improvement in the specificity of competitive immunoassay systems.  相似文献   
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