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991.
The clinical and radiological spectrum of spondylocostal dysostosis syndromes encompasses distinctive costo‐vertebral anomalies. RIPPLY2 biallelic pathogenic variants were described in two distinct cervical spine malformation syndromes: Klippel–Feil syndrome and posterior cervical spine malformation. RIPPLY2 is involved in the determination of rostro‐caudal polarity and somite patterning during development. To date, only four cases have been reported. The current report aims at further delineating the posterior malformation in three new patients. Three patients from two unrelated families underwent clinical and radiological examination through X‐ray, 3D computed tomography and brain magnetic resonance imaging. After informed consent was obtained, family‐based whole exome sequencing (WES) was performed. Complex vertebral segmentation defects in the cervico‐thoracic spine were observed in all patients. WES led to the identification of the homozygous splicing variant c.240‐4T>G in all subjects. This variant is predicted to result in aberrant splicing of Exon 4. The current report highlights a subtype of cervical spine malformation with major atlo‐axoidal malformation compromising spinal cord integrity. This distinctive mutation‐specific pattern of malformation differs from Klippel–Feil syndrome and broadens the current classification, defining a sub‐type of RIPPLY2‐related skeletal disorder. Of note, the phenotype of one patient overlaps with oculo‐auriculo‐vertebral spectrum disorder.  相似文献   
992.
993.
994.
The question whether salpingectomy has a negative influenceon ovarian function and the outcome of pregnancy in an in-vitrofertilization (IVF) and embryo transfer treatment programmeis not yet answered. We performed a retrospective case-controlstudy to investigate the possible negative effect of salpingectomyon ovarian response to human menopausal gonadotrophins (HMG)during IVF and embryo transfer. The study group was composedof 26 patients with bilateral salpingectomy. In 67 cycles weanalysed different parameters of ovulation such as the numberof days of ovarian stimulation, numbers of ampoules of HMG,pre-ovulatory oestradiol concentrations and the numbers of oocytesretrieved. These parameters were compared to a control groupof 134 cycles in 134 women with healthy Fallopian tubes. Nodifferences were found. Implantation ratio, pregnancy rate andoutcome were the same in both groups. We conclude that bilateralsalpingectomy had no detrimental effect on ovarian performanceduring IVF and embryo transfer treatment nor on the outcome.  相似文献   
995.
A t(8;21)(q22;q22) without blood and bone marrow invasion by immature myeloid precursor cells occurred in a patient previously treated for polycythemia vera. The presence of a molecular rearrangement confirmed that the chromosomal abnormality was identical to that observed in acute leukemia with t(8;21). This case shows that the translocation, t(8;21), may occur in myelodysplasia and suggests that it can precede the appearance of overt leukemia.  相似文献   
996.
997.
We previously described the characteristics of a type 1/type 2 (PV-1/PV-2) chimeric poliovirus, v510, which contains the six amino acids specific for PV-2 in the B-C loop of VP1. This virus was found to be mouse-adapted, as PV-2 and in contrast with PV-1. Determinants of host range were studied in detail and are reported here. PV-1/PV-2 chimeras containing partial PV-1----PV-2 substitutions in the B-C loop of VP1 were obtained by making use of a mutagenesis cartridge on PV-1 cDNA. Analysis of mouse neurovirulence of these chimeras, when correlated with the three-dimensional structure of the v510 capsid, revealed that PV-2 residues important for mouse tropism are those which determine the particular conformation of the B-C loop of VP1 in v510. The mutation of the adenine residue at position 480 of the 5' noncoding region into a guanine residue has been shown to be an important determinant of PV-1 attenuation in monkeys. We show that introduction of this mutation in the v510 genome results in a virus which is partially attenuated for mice. This suggests that analysis of genomic determinants important for PV-1 neurovirulence could be carried out in a mouse model by making use of a mouse-adapted PV-1/PV-2 chimera.  相似文献   
998.
Observations of impaired glucose regulation in schizophrenia are long-standing, although their pathological and etiological significance is uncertain. One approach to the issue that minimizes environmental variables (e.g., medication and diet) is to determine whether genes related to glucose regulation show genetic linkage to schizophrenia. We examined the potential role of glucose metabolism in schizophrenia through a genome scan of affection status in schizophrenia and an empirical method for deriving P-values. Data were utilized from the NIMH Genetics Initiative for Schizophrenia dataset, which comprises a total sample consisting of 71 pedigrees containing 218 nuclear families and 987 individuals. A genome scan with 459 markers spaced at an average of 10 cM intervals was conducted using the linkage analysis program Genehunter separately for European- and African-American groups. Enzymes that regulate glycolysis were identified and the genes regulating these enzymes were located through the Online Mendelian Inheritance in Man (OMIM) website. The focus in this study was on genes located near previously reported schizophrenia susceptibility regions. The genome-wide significance of these genes to schizophrenia was assessed using permutation testing. When results were adjusted for multiple testing within and across ethnic groups, 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 2 (PFKFB2; chromosome 1q32.2) achieved genome-wide significance (P = 0.04). In addition, hexokinase 3 (HK3; chromosome 5q35.3) was also suggestive of linkage (P = 0.09). For the European-American sample, PFKFB2 (1q32.2), hexokinase 3 (HK3; 5q35.3), and pyruvate kinase 3 (PK3; chromosome 15q23) achieved significance at the 0.05 level. None of the genes showed significance in the African-American sample. Our results provide further support for the view that genes that regulate glucose metabolism may also influence susceptibility to schizophrenia. More generally, they support the view that relationships between glucose dysregulation and schizophrenia are inherent to the disorder, and are not merely epiphenomena related to medication or other treatment factors.  相似文献   
999.
BACKGROUND: The review aimed to compare the effectiveness, safety and acceptability of vasectomy techniques for male sterilization. METHODS: We searched five computerized databases and reference lists of relevant articles and book chapters for randomized controlled trials (RCTs) and controlled clinical trials (CCTs) comparing vasectomy techniques. Two reviewers independently extracted data from eligible articles. RESULTS: Two poor-quality trials compared vas occlusion with clips versus a conventional technique, and four poor-quality trials examined vas irrigation with water versus no irrigation or irrigation with euflavine. No significant differences regarding the primary outcome of time to azoospermia were found. However, one trial reported fewer median number of ejaculations to azoospermia with euflavine rather than water irrigation. An interim report of a high-quality trial comparing vasectomy with and without fascial interposition found more azoospermia with fascial interposition but also more surgical difficulties. CONCLUSIONS: No conclusions can be reached regarding the effectiveness, safety and acceptability of vas occlusion techniques or vas irrigation since only low-quality, underpowered studies were available. Fascial interposition had improved vasectomy success but also increased surgical difficulty. High-quality, adequately reported RCTs are required. More work is also needed in the standardization of follow-up protocols, evaluation of vasectomy success and failure, recanalization and analytical methods.  相似文献   
1000.
We herein present a technical strategy to optimize DNA isolation from paraffin-embedded tissue (PET). This includes the choice of adequate buffers for proteinase K digestion and multiplex PCR amplifications for assessing the appropriateness of DNA extracts for subsequent PCR assays for detecting clonality. We found that the association of proteinase K digestion in nonionic buffer and subsequent extract dilutions accounted for 79% of successful amplifications. A final efficiency of 88% was achieved by additional organic extractions and/or re-extractions. Comparisons were carried out with control DNA extracts from fresh samples to assess the efficiency of each clonality assay. Immunoglobulin CDRIII rearranged region amplification was more efficient for pregerminal center B-cell lymphomas in contrast to CDRII rearrangement detection, which was more effective for germinal and postgerminal lymphomas. T-cell clonality detection by TCRgamma PCR was less efficient in PET samples than in fresh tissues showing that DNA integrity is more critical for TCR than for IGH amplification. Two inconclusive cases without phenotypic markers and two other atypical lymphoproliferations masked by reactive T cells were diagnosed as plasmablastic lymphomas and as monoclonal B-proliferations, respectively, due to IGH rearrangements.  相似文献   
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