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71.
Megan E. Rech John M. McCarthy Chun‐An Chen Jane C. Edmond Veeral S. Shah Daniëlle G. M. Bosch Gerard T. Berry Linford Williams Suneeta Madan‐Khetarpal Dmitriy Niyazov Charles Shaw‐Smith Erin M. Kovar Philip J. Lupo Christian P. Schaaf 《American journal of medical genetics. Part A》2020,182(6):1426-1437
Bosch–Boonstra–Schaaf Optic Atrophy Syndrome (BBSOAS) is an autosomal dominant neurodevelopmental disorder caused by loss‐of‐function variants in NR2F1 and characterized by visual impairment, developmental delay, and intellectual disability. Here we report 18 new cases, provide additional clinical information for 9 previously reported individuals, and review an additional 27 published cases to present a total of 54 patients. Among these are 22 individuals with point mutations or in‐frame deletions in the DNA‐binding domain (DBD), and 32 individuals with other types of variants including whole‐gene deletions, nonsense and frameshift variants, and point mutations outside the DBD. We corroborate previously described clinical characteristics including developmental delay, intellectual disability, autism spectrum disorder diagnoses/features thereof, cognitive/behavioral anomalies, hypotonia, feeding difficulties, abnormal brain MRI findings, and seizures. We also confirm a vision phenotype that includes optic nerve hypoplasia, optic atrophy, and cortical visual impairment. Additionally, we expand the vision phenotype to include alacrima and manifest latent nystagmus (fusional maldevelopment), and we broaden the behavioral phenotypic spectrum to include a love of music, an unusually good long‐term memory, sleep difficulties, a high pain tolerance, and touch sensitivity. Furthermore, we provide additional evidence for genotype–phenotype correlations, specifically supporting a more severe phenotype associated with DBD variants. 相似文献
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73.
Involvement of ERK, p38 and NF-kappaB signal transduction in regulation of TLR2, TLR4 and TLR9 gene expression induced by lipopolysaccharide in mouse dendritic cells 总被引:7,自引:0,他引:7 下载免费PDF全文
An H Yu Y Zhang M Xu H Qi R Yan X Liu S Wang W Guo Z Guo J Qin Z Cao X 《Immunology》2002,106(1):38-45
Toll-like receptors (TLR) are sentinel receptors capable of recognizing pathogen-associated molecule patterns (PAMP) such as lipopolysaccharide (LPS) and CpG-containing oligonucleotides (CpG ODN). TLR2 and TLR4 are major receptors for Gram-positive and Gram-negative bacterial cell wall components, respectively. TLR9 is necessary for CpG signalling. LPS or CpG ODN can activate immature dendritic cells (DC) and induce DC maturation characterized by production of cytokines, up-regulation of co-stimulatory molecules, and increased ability to activate T cells. However, little is known regarding the regulation of TLR gene expression in mouse DC. In this study, we investigated the regulation of TLR2, TLR4 and TLR9 gene expression by LPS in murine immature DC. TLR2, TLR4 and TLR9 mRNA were up-regulated following LPS stimulation. The up-regulation of TLR9 expression coincided with significantly increased production of tumour necrosis factor-alpha induced by LPS plus CpG ODN. While inhibition of extracellular signal-related kinase and NF-kappaB activation suppressed the up-regulation of the expression of TLR2, TLR4 and TLR9 mRNA, inhibition of p38 kinase prevented the up-regulation of TLR2 and TLR4 mRNA expression but enhanced the up-regulation of TLR9 expression. These results demonstrated that TLR2, TLR4 and TLR9 gene expression was differently regulated by LPS in mouse immature DC. Up-regulation of TLR2, TLR4 and TLR9 expression by LPS might promote the overall responses of DC to bacteria and help to explain the synergy between LPS and other bacterial products in the induction of cytokine production. 相似文献
74.
研究单次及长期维持血液透析时尿毒症患者血液流变性改变的影响。结果表明,单次血透后,红细胞比积明显升高,红细胞刚性明显降低;血浆粘度、红细胞聚集指数、Casson粘度、血液屈服应力及低切至高切的全血粘度无明显改变。维持血透患者的红细胞比积、血浆粘度、红细胞聚集指数、Casson粘度、血液屈服应力均无明显改变。进一步研究发现,单次血透后血浆渗透比明显降低.这可能是引起红细胞比积升高、红细胞刚性降低的原因之一。 相似文献
75.
Xanthii Fructus (XF) is an herb widely used in medicine for the treatment of a variety of inflammatory pathologies. In this study, using mouse peritoneal macrophages, we have examined whether XF affects nitric oxide (NO), tumor necrosis factor (TNF)-α, and interleukin (IL)-12p40 production induced by interferon (IFN)-γ and lipopolysaccharide (LPS). XF inhibits IFN-γ and LPS-induced NO production in a dose dependent manner. The decrease in NO synthesis was reflected as a decreased amount of inducible NO synthase protein. Furthermore, we also found that XF inhibits pro-inflammatory cytokine TNF-α production. However, treatment of XF in peritoneal macrophages had no effect on IL-12p40 production. These findings suggest that XF may be used in controlling macrophages-mediated inflammatory diseases. 相似文献
76.
Widespread skin and soft-tissue infections due to two methicillin-resistant Staphylococcus aureus strains harboring the genes for Panton-Valentine leucocidin 总被引:9,自引:0,他引:9 下载免费PDF全文
Diep BA Sensabaugh GF Somboonna N Somboona NS Carleton HA Perdreau-Remington F 《Journal of clinical microbiology》2004,42(5):2080-2084
Infections caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) are emerging as a major public health problem. CA-MRSA has been associated previously with skin and soft-tissue infection (SSTI) and with carriage of staphylococcal cassette chromosome mec (SCCmec) type IV and the Panton-Valentine leucocidin (PVL) virulence factor. To assess the clonal distribution of PVL-carrying strains and the association with SSTI in the San Francisco Bay area, we surveyed six collections of S. aureus isolates-671 isolates in all-collected between 1997 and 2002 originating from inpatient and outpatient clinical specimens and from a community-based sampling. Isolates were genotyped by pulsed-field gel electrophoresis, multilocus restriction fragment typing, and multilocus sequence typing and assayed for the PVL virulence factor. The S. aureus populations showed a high proportion of PVL-carrying strains, with frequencies ranging up to 70% in MRSA isolated from jail inmate patients and 69% in MRSA from patients receiving surgical treatment at an outpatient clinic specializing in treating SSTIs. PVL-carrying isolates were identified in nine clonal groups, but 88.5% of the PVL-carrying MRSA isolates belonged to only two clonal groups. These two clonal groups carried the SCCmec type IV resistance determinant and were more likely than other clonal groups to be recovered from SSTI sites than from other sites (P < 0.0001). There is evidence of clonal replacement over the period from 1999 to 2002, with one of these two clonal groups being supplanted by the other. 相似文献
77.
An J Zhou DS Kawasaki K Yasui K 《Virchows Archiv : an international journal of pathology》2003,442(5):472-481
To investigate the mechanisms of dengue (DEN) virus transmission within the spinal cord, severe combined immunodeficient mice were intracerebrally inoculated with DEN virus type 2. After inoculation, a high virus titer and antigens were detected in the brain and spinal cord. At early stages of the infection, ultrastructural examinations showed that a few virions were present in the cytoplasm of ependymal cells lining the central canal. As the infection progressed, virions were observed in the lumen of the rough endoplasmic reticulum (RER), RER-derived vesicles and the Golgi region of infected neurons. These data suggest that the inoculated DEN virus might spread to the neurons of the spinal cord via the cerebral spinal fluid and cause several neuronal pathological responses. Moreover, DEN virus was also observed in myelinated and unmyelinated nerve fibers and typical neuronal synapses. Some virion-containing vesicles appeared to be fused with the membrane of presynapses, indicating that neuron-to-neuron transport of DEN virus might occur in the spinal cord. Additionally, anterior, lateral and posterior horns of the spinal cord exhibited different numbers of the positive neurons and different staining intensities of the DEN antigen during the infection. This difference likely represents variation of susceptibility to the DEN virus among the neurons of the spinal cord. 相似文献
78.
Quantification of HIV DNA in the brain by PCR: differences between fresh frozen and formalin fixed tissue. 下载免费PDF全文
HIV-1 DNA extracted from frozen and formalin fixed brain tissue can be detected using PCR. This work has been extended by amplifying, using semiquantitative PCR, HIV DNA extracted from frontal lobe tissue of 16 patients with AIDS (eight positive and eight negative for p24 antigen). DNA was amplified using HIV-1 pol gene digoxigenin labelled primers and detected by chemiluminescence and densitometry. Cloned standards were amplified in parallel for quantification. HIV DNA levels detected in frozen tissue showed a correlation with p24 positivity and the severity of the histological diagnosis. This correlation was less clear in the formalin fixed material. 相似文献
79.
80.
The infrapyloric artery and cephalic pancreatoduodenectomy with pylorus preservation: preliminary study 总被引:1,自引:0,他引:1
Ph Wind JM Chevallier JJ Sarcy V Delmas PH Cugnenc 《Surgical and radiologic anatomy : SRA》1994,16(2):165-172
Summary Cephalic pancreatoduodenectomy (CPD) with pylorus preservation has been suggested to improve the functional and nutritional result of surgery. At operation, the first two centimeters of the duodenum are preserved, the vascular arch of the lesser gastric curvature is saved and the right gastroepiploic artery is resected at its origin. The aim of this study on 15 fresh cadavers was to determine the origin of the vascularization of the remaining duodenum and also the possibilities of preserving an optimal vascularization after CPD and pylorus preservation. All of the arteries supplying the remaining duodenum and arising either from the right gastric artery or the right gastroepiploic artery were identified. The distances between the origin of the infrapyloric artery and the termination of the gastroduodenal artery on the cranial and ventral pancreaticoduodenal artery and the left gastroepiploic artery were measured. At CPD with pylorus preservation, the study demonstrated that: 1) the cranial side of the remaining duodenum remains vascularized in 80% of the cases by one or two supraduodenal branches coming from the right gastric artery; 2) ligation of the right gastroepiploic artery eliminates all vascular supply to the caudal side of the remaining duodenum in almost half of the cases; 3) in these cases, the dissection of the bifurcation of the gastroduodenal artery and the vascular section beyond the origin of the infrapyloric artery allowed a direct vascular supply to the remaining duodenum to be preserved.This work was presented at the French Section of the European Association of Clinical Anatomy meeting, Bobigny, France, 1992 相似文献