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41.
Zinc finger protein 462 (ZNF462) is a relatively newly discovered vertebrate specific protein with known critical roles in embryonic development in animal models. Two case reports and a case series study have described the phenotype of 10 individuals with ZNF462 loss of function variants. Herein, we present 14 new individuals with loss of function variants to the previous studies to delineate the syndrome of loss of function in ZNF462. Collectively, these 24 individuals present with recurring phenotypes that define a multiple congenital anomaly syndrome. Most have some form of developmental delay (79%) and a minority has autism spectrum disorder (33%). Characteristic facial features include ptosis (83%), down slanting palpebral fissures (58%), exaggerated Cupid's bow/wide philtrum (54%), and arched eyebrows (50%). Metopic ridging or craniosynostosis was found in a third of study participants and feeding problems in half. Other phenotype characteristics include dysgenesis of the corpus callosum in 25% of individuals, hypotonia in half, and structural heart defects in 21%. Using facial analysis technology, a computer algorithm applying deep learning was able to accurately differentiate individuals with ZNF462 loss of function variants from individuals with Noonan syndrome and healthy controls. In summary, we describe a multiple congenital anomaly syndrome associated with haploinsufficiency of ZNF462 that has distinct clinical characteristics and facial features.  相似文献   
42.
Pachytene quadrivalents are described in a male heterozygous for a balanced reciprocal translocation between the long arms of chromosomes 10 and 11. The break points of the translocation occur at 10q23 and 11q24. The main chromomere patterns of the bivalents correspond to the main G bands in mitosis and are sufficiently pronounced to allow the identification of bivalents 10 and 11 in normal spermatocytes.  相似文献   
43.
Helicobacter spp., except for Helicobacter cinaedi, have only rarely been reported in cases of septicemia. A patient with X-linked (Bruton's) agammaglobulinemia was found to have persistent sepsis with a Helicobacter-like organism despite multiple courses of antibiotics. His periods of sepsis were associated with leg swelling thought to be consistent with cellulitis. The organism was fastidious and required a microaerophilic environment containing H(2) for growth. Optimal growth was observed at 35 to 37 degrees C on sheep blood, CDC anaerobe, and Bordet-Gengou agars. Serial subcultures every 4 to 5 days were required to maintain viability. The organism was strongly urease positive and showed highest relatedness to Helicobacter-like organisms with the vernacular name "Flexispira rappini" by 16S rRNA gene sequence analysis. Genomic DNA hybridization studies, however, found 24 to 37% relatedness to "F. rappini" and even less to other Helicobacter spp. Although the organism phenotypically resembles "Flexispira" and Helicobacter, it is thought to represent a new taxon. The patient's infection was eventually cleared with a prolonged (5-month) course of intravenous imipenem and gentamicin.  相似文献   
44.
The kidney plays a major role in maintaining and controlling systemic acid–base homeostasis by reabsorbing bicarbonate and secreting protons and acid-equivalents, respectively. During postnatal kidney development and adaptation to changing diets, plasma bicarbonate levels are increasing, the capacity for urinary acidification maturates, and the final morphology and distribution of intercalated cells is achieved. In adult kidney, at least two types of intercalated cells (IC) are found along the collecting duct characterised either by the expression of AE1 (type A IC) or pendrin (non-type A IC) where non-type A IC are found only in the convoluted distal tubule, connecting tubule and cortical collecting duct. Here we investigated in mouse kidney the relative mRNA abundance, protein expression levels and distribution of several proteins involved in renal acid–base transport, namely, the Na+/HCO3 cotransporter NBC1 (SLC4A4), the Na+/H+-exchanger NHE3 (SLC9A3), two subunits of the vacuolar H+-ATPase [ATP6V0A4 (a4), ATP6V1B1 (B1)], the Cl/HCO3 exchangers AE1 (SLC4A1) and pendrin (SLC26A4). Relative mRNA abundance of all transport proteins was lowest at day 3 after birth and increased thereafter in parallel with protein levels. The numbers of type A and non-type A IC in the cortical collecting duct (CCD) increased from day 3 to days 18 and 24, whereas the number of IC in the CCD with apical staining for the vacuolar H+-ATPase subunits a4 and B1 decreased from day 3 to days 18 and 24, respectively. In addition, cells with characteristics of non-type A IC (pendrin expression, basolateral expression of vacuolar H+-ATPase subunits) were found in the inner and outer medulla 3 days after birth but were absent from the medulla of 24-day-old mice. Taken together, these results demonstrate massive changes in mRNA and protein expression levels of several acid–base transporters during postnatal kidney maturation and also show changes in intercalated cell phenotype in the medulla during these processes.  相似文献   
45.
Severe acute respiratory syndrome (SARS) is caused by a novel and highly infectious virus named SARS coronavirus (SARS-CoV). Among the serological tests currently available for the detection of SARS-CoV, a whole-virus-based immunofluorescence assay (IFA) was considered one of the most sensitive assays and served as a "gold standard" during the SARS epidemic in Singapore in 2003. However, the need to manipulate live SARS-CoV in the traditional IFA limits its wide application due to the requirement for a biosafety level 3 laboratory and the risk of laboratory infection. Previously, we have identified two immunodominant epitopes, named N195 and Sc, in the two major structural proteins, the N and S proteins, of SARS-CoV (Q. He, K. H. Chong, H. H. Chng, B. Leung, A. E. Ling, T. Wei, S. W. Chan, E. E. Ooi, and J. Kwang, Clin. Diagn. Lab. Immunol., 11:417-422, 2004; L. Lu, I. Manopo, B. P. Leung, H. H. Chng, A. E. Ling, L. L. Chee, E. E. Ooi, S. W. Chan, and J. Kwang, J. Clin. Microbiol. 42:1570-1576, 2004). In the present study, the N195-Sc fusion protein was highly expressed in insect (Sf9) cells infected with a recombinant baculovirus bearing the hybrid gene under the control of a polyhedrin promoter. An IFA based on Sf9 cells producing the fusion protein was standardized with 23 serum samples from patients with SARS, 20 serum samples from patients with autoimmune diseases, and 43 serum samples from healthy blood donors. The detection rates were comparable to those obtained with a commercial SARS-CoV IFA kit (EUROIMMUN, Gross Groenau, Germany) and a conventional IFA performed at the Singapore General Hospital. Our data showed that the newly developed IFA could detect SARS-CoV in 22 of the 23 SARS-CoV-positive serum samples and gave no false-positive results when the sera from patients with autoimmune diseases and healthy individuals were tested. The detection rate was identical to those of the two whole-virus-based IFAs. Thus, the novel N-S fusion antigen-based IFA could be an attractive alternative to present whole-virus-based IFAs for the diagnosis of SARS-CoV infection.  相似文献   
46.
ABSTRACT

Electrical Stimulation (ES) is a neurostimulation technique that is used to localize language functions in the brain of people with intractable epilepsy and/or brain tumors. We reviewed 25 ES articles published between 1984 and 2018 and interpreted them from a cognitive neuropsychological perspective. Our aim was to highlight ES as a tool to further our understanding of cognitive models of language. We focused on associations and dissociations between cognitive functions within the framework of two non-neuroanatomically specified models of language. Also, we discussed parallels between the ES and the stroke literatures and showed how ES data can help us to generate hypotheses regarding how language is processed. A good understanding of cognitive models of language is essential to motivate task selection and to tailor surgical procedures, for example, by avoiding testing the same cognitive functions and understanding which functions may be more or less relevant to be tested during surgery.  相似文献   
47.
Disclosure of the results of a positive genetic mutation to offspring can be challenging. The purpose of this study was to investigate the content and process of disclosure from BRCA1/2 carriers to their offspring. A semi-structured questionnaire focused on the disclosure processes between parent and offspring. Thirty-one/40 mothers with BRCA1/2 mutations completed the cross-sectional survey. Sixteen carriers (51.6%) chose to disclose their results to all of their children, thirteen carriers (41.9%) chose not to disclose their results, and two carriers (6.5%) chose to disclose to some of their children. The age of a child appeared to be the most significant contributing factor in the decision to disclose. The mean age of the offspring who learned of the positive test result was 24.3 years with most carriers advocating the ideal age range for disclosure from 19 to 25 years. There was a discrepancy between actual and potential disclosure topics between those who had disclosed and those who had not disclosed at the time of the survey. Women who disclosed their result tended to do so alone, within a week of learning their own results, equally to male and female offspring and expressed that the relationships between themselves and their children had strengthened since revealing the presence of a genetic mutation in the family. Women who had not disclosed the results of their genetic test to offspring were significantly more interested in receiving additional individual counseling, educational videos, and email newsletters that focus on disclosure of this complex and life altering information compared to those who had already disclosed. Disclosure of BRCA1/2 results is determined primarily by age of offspring, is usually done by women alone, relatively soon after receiving results and appears to enhance the relationships between mothers and offspring. Both disclosed and non-disclosed carriers demonstrated significant interest in a variety of interventions to support the disclosure process.  相似文献   
48.
Allelic loss of chromosome 6q in gastric carcinoma.   总被引:1,自引:0,他引:1  
Loss of the long arm of chromosome 6 (6q) has frequently been reported in gastric carcinoma, and most gastric cancer patients have evidence of intestinal metaplasia in the stomach. However, the relationship between loss of chromosome 6q and intestinal metaplasia has not been studied. In the first part of the study, we define the critical deletion region of chromosome 6q using loss of heterozygosity technique (LOH). Seventeen microsatellite markers were used to detect loss of heterozygosity (LOH) in 37 microdissected gastric tumors. We also examined intestinal metaplasia (IM) foci of the stomach in the same cancer patient (17 cases). Losses on chromosome 6q were detected in high frequency (51%) by LOH. Two distinct regions of common allelic loss were identified: one centered on the marker D6S300 (at 6q16.1) and the second on D6S446 (at 6q27), with LOH frequency of 36% and 31.3%, respectively. The deletions fall into 2 discrete regions, suggesting the existence of at least 2 tumor suppressor genes in 6q. The losses at 6q27 were confirmed by fluorescence in situ hybridization study (FISH). In the cases with LOH in the tumor, no LOH were detected in the autologous IM areas, but losses were detected by FISH. In some cases, these genetic changes may be acquired in the transition from normal gastric mucosa to intestinal metaplasia.  相似文献   
49.
Clostridium botulinum neurotoxins (BoNTs) are the most toxic proteins for humans. The current clostridial-derived vaccines against BoNT intoxication have limitations including production and accessibility. Conditions were established to express the soluble receptor binding domain (heavy-chain receptor [HCR]) of BoNT serotypes A and E in Escherichia coli. Sera isolated from mice and rabbits immunized with recombinant HCR/A1 (rHCR/A1) from the classical type A-Hall strain (ATCC 3502) (BoNT/A1) and rHCR/E from BoNT serotype E Beluga (BoNT/E(B)) neutralized the homologous serotype of BoNT but displayed differences in cross-recognition and cross-protection. Enzyme-linked immunosorbent assay and Western blotting showed that alpha-rHCR/A1 recognized epitopes within the C terminus of the HCR/A and HCR/E, while alpha-rHCR/E recognized epitopes within the N terminus or interface between the N and C termini of the HCR proteins. alpha-rHCR/E(B) sera possessed detectable neutralizing capacity for BoNT/A1, while alpha-rHCR/A1 did not neutralize BoNT/E. rHCR/A was an effective immunogen against BoNT/A1 and the Kyoto F infant strain (BoNT/A2), but not BoNT serotype E Alaska (BoNT/E(A)), while rHCR/E(B) neutralized BoNT/E(A), and under hyperimmunization conditions protected against BoNT/A1 and BoNT/A2. The protection elicited by rHCR/A1 to BoNT/A1 and BoNT/A2 and by rHCR/E(B) to BoNT/E(A) indicate that immunization with receptor binding domains elicit protection within sub-serotypes of BoNT. The protection elicited by hyperimmunization with rHCR/E against BoNT/A suggests the presence of common neutralizing epitopes between the serotypes E and A. These results show that a receptor binding domain subunit vaccine protects against serotype variants of BoNTs.  相似文献   
50.
Individual differences in psychopathology, personality, and nicotine responsitivity and their biological bases are evaluated as mechanisms potentially mediating smoking heritability. Smokers are more likely to be high in neurotic traits (e.g., depression, anxiety, anger) and in social alienation (psychoticism, impulsivity, unsocialized sensation-seeking, low conscientiousness, low agreeableness) and low in achievement/socioeconomic status. Psychological and biological mechanisms putatively mediating these associations are reviewed. It is concluded that a number of relatively indirect and complex processes, as well as more direct (e.g., self-medication for psychopathology, nicotine sensitivity), mediate the inheritance of smoking behavior.  相似文献   
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