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1.
Background: Ehlers-Danlos syndrome (EDS) is a common non-inflammatory, congenital connective tissue disorder. Classical type (cEDS) EDS is one of the more common forms, typically caused by mutations in the COL5A1 and COL5A2 genes, though causative mutations in the COL1A1 gene have also been described. Material and methods: The study group included 59 patients of Polish origin, diagnosed with cEDS. The analysis was performed on genomic DNA (gDNA) with NGS technology, using an Illumina sequencer. Thirty-five genes related to connective tissue were investigated. The pathogenicity of the detected variants was assessed by VarSome. Results: The NGS of 35 genes revealed variants within the COL5A1, COL5A2, COL1A1, and COL1A2 genes for 30 of the 59 patients investigated. Our panel detected no sequence variations for the remaining 29 patients. Discussion: Next-generation sequencing, with an appropriate multigene panel, showed great potential to assist in the diagnosis of EDS and other connective tissue disorders. Our data also show that not all causative genes giving rise to cEDS have been elucidated yet.  相似文献   

2.
应用复合PCR结合变性高效液相色谱(DHPLC)技术,建立乳粉中普通变形杆菌和奇异变形杆菌的高通量检测方法。根据普通变形杆菌的blaA和blaB基因及奇异变形杆菌的ureR基因序列分别设计特异性引物,复合PCR扩增的产物经DHPLC技术进行快速检测,并以37株参考菌株做特异性试验。试验结果表明,该方法具有很好的特异性,经复合PCR-DHPLC可同时检测乳粉中普通变形杆菌和奇异变形杆菌。该方法可以快速、准确、高通量检测普通变形杆菌和奇异变形杆菌,是乳粉中致病菌高通量检测的新技术。  相似文献   

3.
High rates of hydrogen photoproduction are obtained when glutaraldehyde-fixed Photosystem I-enriched vesicles (Photosystem II-depleted) are added to hydrogenase-containing cells of Proteus mirabilis in the presence of the mediator methylviologen and a suitable electron donating system. This donor system includes ascorbate, dithioerythritol (DTE) and the mediator tetramethylphenylene-diamine (TMPD) and reduces the photosynthetic electron transfer chain at the level of plastocyanin. Both DTE and ascorbate are required for hydrogen photoproduction, DTE being the ultimate electron donor and ascorbate only having a catalytic function. Whereas the aerobic photoreduction of methylviologen is similar in the presence of DTE, ascorbate or both, under anaerobic conditions only combination of both compounds results in a high and stable amount of reduced methylviologen that can be utilized by the hydrogenase. It is concluded that oxidation reactions of reduced methylviologen, competing with the hydrogenase, rather than methylviologen photoreduction, limit hydrogen photoproduction in the presence of either DTE or ascorbate. These oxidation reactions are suggested to involve back reactions to the oxidized form(s) of ascorbate and DTE but backflow to the photosynthetic electron transfer chain (i.e. cyclic electron transfer) can not be excluded.Abbreviations Tes N-tris (hydroxymethyl) methyl-2-aminoethanesulfonic acid - DTE 1,4-dithioerythritol - TMPD, N,N,N N-tetramethyl-p-phenylenediamine - DCMU 3-(3, 4-dichlorophenyl)-1, 1,-dimethylureum - EDAC 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide - DNP-INT 2-iodo-6-isopropyl-3-methyl-2, 4, 4-trinitrodiphenyl ether - DBMIB 2,5-dibromo-3-methyl-6-isopropyl-benzoquinone - PS photosystem - Chl chlorophyll  相似文献   

4.
Abnormalities in type I collagen have been recognized in a number of connective tissue disorders. In the Marfan syndrome, an autosomal dominant condition producing a generalized abnormality in connective tissue, no consistent abnormality has been identified, although one individual has been found to have an elongated pro alpha 2(I) collagen chain [Byers et al, Proc Natl Acad Sci USA 78:7745, 1981]. To determine the nature of the alteration in the gene that produced this abnormality, we studied the pro alpha 2(I) gene from this individual by genomic blotting and gene cloning. Genomic mapping studies detected no abnormalities. However, analysis of the cloned segment of the pro alpha 2(I) collagen gene from the Marfan individual indicates that the gene contains a 38 base pair insertion in an intron near the collagenase cleavage site. Although the relationship of this insertion to the protein abnormality is unclear, it may be a useful marker for the diagnosis of the Marfan syndrome.  相似文献   

5.
Summary In this paper an immunodominant epitope of Topoisomerase I is described. An epitope expression sublibrary was constructed from Topoisomerase I cDNA. The subclones were screened with an antiserum from a patient with systemic sclerosis (SSc). The positive clones defined one immunodominant B cell epitope (epitope III), which was located at the carboxyterminal part of the protein. The epitope, 52 amino acids in length, neither contains the p 30gag sequence nor the suggested active site Tyr-723, both presumed antibody recognition sites.More than 70% of our anti-TopoI sera recognize this epitope III, indicating that it is a major recognition site of the anti-TopoI autoantibodies in SSc sera. DNA relaxation experiments show that all sera that recognize epitope III and most sera with antibodies to other epitopes inhibit Topoisomerase I activity.Abbreviations used in this paper SSc Systemic sclerosis - Topol DNA Topoisomerase I (EC 5.99.1.2)  相似文献   

6.
We measured the activities of the cholinergic marker enzymes choline acetyltransferase (ChAT) and acetylcholinesterase (AChE) in autopsied brains of seven infants (age range 3 months to 1 year) with Down's syndrome (DS), a disorder in which virtually all individuals will develop by middle age the neuropathological changes of Alzheimer's disease accompanied by a marked brain cholinergic reduction. When compared with age-matched controls cholinergic enzyme activity was normal in all brain regions of the individuals with infant DS with the exception of above-normal activity in the putamen (ChAT) and the occipital cortex (AChE). Our neurochemical observations suggest that DS individuals begin life with a normal complement of brain cholinergic neurons. This opens the possibility of early therapeutic intervention to prevent the development of brain cholinergic changes in patients with DS.  相似文献   

7.
Background: Loeys-Dietz syndrome (LDS) is a newly recognised disorder of connective tissue which shares overlapping features with Marfan syndrome (MFS) and the vascular type of Ehlers- Danlos syndrome, including aortic root dilatation and skin abnormalities. It is clinically classified into types 1 and 2. LDS type 1 can be recognised by craniofacial characteristics, e.g. hypertelorism, bifid uvula or cleft palate, whereas these are absent in LDS type 2. It is important to recognise LDS because its vascular pathology is aggressive. We describe nine LDS patients from four families, relate their features to published cases, and discuss important aspects of the diagnosis and management of LDS in order to make clinicians aware of this new syndrome. Results: Characteristics found in the majority of these LDS patients were aortic root dilatation, cleft palate and/or a bifid/abnormal uvula. Conclusion: Because aortic dissection and rupture in LDS tend to occur at a young age or at aortic root diameters not considered at risk in MFS, and because the vascular pathology can be seen throughout the entire arterial tree, patients should be carefully followed up and aggressive surgical treatment is mandatory. Clinicians must therefore be aware of LDS as a cause of aggressive aortic pathology and that its distinguishing features can sometimes be easily recognised. (Neth Heart J 2008;16:299-304.)  相似文献   

8.
Proteus mirabilis is a urinary pathogen that can differentiate from a swimmer cell into a swarmer cell morphotype and can form biofilms on the surfaces of urinary catheters. These biofilms block these catheters due to crystals trapped within these structures. The effect of encrustation on biofilm formation and structure has not been studied using confocal scanning laser microscopy (CSLM). Therefore, a comparison of biofilm structure in artificial urine (AU) and laboratory media was undertaken. We compared the structure of P. mirabilis biofilms in AU and Luria-Bertani broth using CSLM and 3D imaging. Biofilms grown in Luria-Bertani broth formed mushroom structures at 24 h and contained nutrient channels. AU biofilms were observed to form a different structure at 24 h. AU biofilm structure was observed to be a flat layer, almost devoid of nutrient channels. Swarmer cells were observed protruding out of the biofilm into the bulk fluid. This could be due to nutrient depravation within the biofilm or a means of further colonizing the surface. This study has demonstrated that two markedly different biofilm structures are formed, depending on the growth media utilized.  相似文献   

9.
马瑞风  王丽岩  贺立新  汪宇 《生物磁学》2011,(18):3434-3437
目的:探讨膜联蛋白I(AnnexinI)在多囊卵巢综合征(PCOS)大鼠卵泡颗粒细胞的表达及生物学意义。方法:采用免疫组织化学方法及灰度值测定AnnexinI在PCOS组和对照组的卵泡颗粒细胞中的表达。结果:AnnexinI在两组中的各级卵泡颗粒细胞中均有表达,PCOS组AnnexinI在窦状卵泡中表达显著高于对照组(P〈0.05)。结论:PCOS组AnnexinI在窦状卵泡颗粒细胞的表达上调,且PCOS中窦状卵泡颗粒细胞的凋亡增加,说明AnnexinI参与了卵巢颗粒细胞的凋亡过程,并且发挥了重要作用。  相似文献   

10.
XerC and XerD are two site-specific recombinases, which act on different sites to maintain replicons in a monomeric state. This system, which was first discovered and studied in Escherichia coli, is present in several species including Proteus mirabilis, where the XerD recombinase was previously characterized by our laboratory. In this paper, we report the presence of the xerC gene in P. mirabilis. Using in vitro reactions, we show that the two P. mirabilis recombinases display binding and cleavage activity on the E. coli dif site and the ColE1 cer site, together or in collaboration with E. coli recombinases. In vivo, P. mirabilis XerC and XerD are able to resolve and monomerize a plasmid containing two cer sites, increasing its stability. However, P. mirabilis XerC, in combination with E. coli XerD, is unable to perform these functions.  相似文献   

11.
Basic histological sections (with different staining methods) and scanning electron microscopy (SEM) examinations showed that there were three distinctive layers in the adipose eyelid of milkfish Chanos chanos , which is found in the cephalie region and covers the entire eye. The outer and inner layers were epithelial tissues and the middle layer was composed of connective tissue formed by type I collagen fibrils. No adipose tissue was found in any of the three layers of the so-called adipose eyelid. Examination by transmission spectrophotometer showed that the adipose tissue could filter out ambient light with a wavelength shorter than 305 nm. A photoretinoscope was used to investigate whether the adipose eyelid influenced the mechanism of eye focusing. Eye diopter values did not differ before or after eyelid removal, which indicated that the adipose eyelid did not play a role in eye focusing. In light of these findings, it is suggested that the adipose eyelid serves to block exposure of harmful ultraviolet light into eyes and may also to offer some protection against impact to the eye in the aquatic environment.  相似文献   

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14.
Bacterial infections cause serious illnesses that are treated with antibiotics. Currently used methods for detecting bacterial antibiotic susceptibility consume 48–72 h, leading to overuse of antibiotics. Thus, many bacterial species have acquired resistance to a broad range of available antibiotics. There is an urgent need to develop efficient methods for rapid determination of bacterial susceptibility to antibiotics. The combination of machine learning and Fourier-transform infrared (FTIR) spectroscopy has generated a promising diagnostic approach in medicine and biology. Our main goal is to examine the potential of FTIR spectroscopy to determine the susceptibility of urinary tract infection-Proteus mirabilis to a specific range of antibiotics, within about 20 min after 24 h culture and identification. We measured the infrared spectra of 489 different P. mirabilis isolates and used random forest to analyze this spectral database. A classification success rate of ~84% was achieved in differentiating between the resistant and sensitive isolates based on their susceptibility to ceftazidime, ceftriaxone, cefuroxime, cefuroxime axetil, cephalexin, ciprofloxacin, gentamicin, and sulfamethoxazole antibiotics in a time span of 24 h instead of 48 h.  相似文献   

15.
16.
Existing data suggest the extracellular matrix (ECM) of vertebrate skeletal muscle consists of several morphologically distinct layers: an endomysium, perimysium, and epimysium surrounding muscle fibers, fascicles, and whole muscles, respectively. These ECM layers are hypothesized to serve important functional roles within muscle, influencing passive mechanics, providing avenues for force transmission, and influencing dynamic shape changes during contraction. The morphology of the skeletal muscle ECM is well described in mammals and birds; however, ECM morphology in other vertebrate groups including amphibians, fish, and reptiles remains largely unexamined. It remains unclear whether a multilayered ECM is a common feature of vertebrate skeletal muscle, and whether functional roles attributed to the ECM should be considered in mechanical analyses of non-mammalian and non-avian muscle. To explore the prevalence of a multilayered ECM, we used a cell maceration and scanning electron microscopy technique to visualize the organization of ECM collagen in muscle from six vertebrates: bullfrogs (Lithobates catesbeianus), turkeys (Meleagris gallopavo), alligators (Alligator mississippiensis), cane toads (Rhinella marina), laboratory mice (Mus musculus), and carp (Cyprinus carpio). All muscles studied contained a collagen-reinforced ECM with multiple morphologically distinct layers. An endomysium surrounding muscle fibers was apparent in all samples. A perimysium surrounding groups of muscle fibers was apparent in all but carp epaxial muscle; a muscle anatomically, functionally, and phylogenetically distinct from the others studied. An epimysium was apparent in all samples taken at the muscle periphery. These findings show that a multilayered ECM is a common feature of vertebrate muscle and suggest that a functionally relevant ECM should be considered in mechanical models of vertebrate muscle generally. It remains unclear whether cross-species variations in ECM architecture are the result of phylogenetic, anatomical, or functional differences, but understanding the influence of such variation on muscle mechanics may prove a fruitful area for future research.  相似文献   

17.
Objective: To use standardized cut‐offs of body mass index (BMI), waist circumference, waist‐to‐hip ratio, and fasting insulin levels to predict the development of metabolic disorders and metabolic syndrome. Research Methods and Procedures: We performed an 8‐year follow‐up study of 628 non‐Hispanic whites and 1340 Mexican Americans, ages 25 to 64 years, from the second cohort of the San Antonio Heart Study. We defined metabolic disorders as dyslipidemia (triglycerides ≥2.26 mM or high‐density lipoprotein <0.91 mM in men and <1.17 mM in women), hypertension (blood pressure ≥140/≥90 mm Hg, or receiving antihypertensive medications), and type 2 diabetes (fasting glucose ≥7.0 mM, 2‐hour test glucose ≥11.1 mM, or receiving anti‐diabetic medications). People with at least two metabolic disorders were defined as having metabolic syndrome. Results: High waist‐to‐hip ratio and fasting insulin levels were significant predictors of developing metabolic syndrome. High anthropometric indices remained significant predictors of metabolic syndrome after adjusting for fasting insulin. Waist circumference, BMI, and insulin had similar areas under the receiver operating characteristic curves (0.74 to 0.76). Further multivariate analyses combining these indices showed minimal increase in prediction. Of subjects who had a combination of high BMI (≥30 kg/m2) and high waist circumference (above “Action Level 2”), 32% developed metabolic syndrome, compared with 10% of subjects with both low BMI and low waist circumference. Discussion: These findings support the National Institutes of Health recommendations for reducing the risk of metabolic syndrome. Adjustment for baseline fasting insulin levels had only a small effect on the ability of anthropometric indices to predict the metabolic syndrome.  相似文献   

18.
目的了解本地区2007年到2010年奇异变形杆菌的临床分布与常用抗菌药物的耐药情况,了解碳青霉烯类耐药菌株可能存在的机制。方法回顾分析2007年到2010年临床分离奇异变形杆菌的资料及整体耐药情况;对保存的耐亚胺培南(IPM)、美罗培南(MEM)或厄他培南(ETP)的菌株进行复苏,并做Hoage试验进行产碳青霉烯酶的确认,同时对试验菌株进行耐药基因的PCR扩增检测。结果2007年到2010年,奇异变形杆菌在临床各送检样本中以痰液分离率最高:51.1%、34.4%、22.1%和35.4%,其次为尿液:14.3%、28.O%、34.9%和33.6%;耐药监测分析显示,4年间对喹诺酮类、青霉素类、头孢菌素类及氨基糖苷类耐药率相对较高且较为稳定;对碳青霉烯类耐药最低但增加明显,亚胺培南从2007年的1.8%升到2010年的16.1%,美罗培南从2007年的1.7%升到2010年的16.8%。15株耐碳青霉烯类菌株中,Hoage试验阳性7株,6fn。基因阳性11株,blaCTX-M基因阳性13株。结论本地区奇异变形杆菌对临床常用的抗菌药物均有较高的耐药性,对碳青霉烯类药物的耐药率最低,但增加明显。位于质粒上的blaKPc基因所产生的碳青霉烯酶和6如cTx-M基因所产生的超广谱β-内酰胺酶是本菌对β-内酰胺类抗菌药物耐药的主要原因,临床应引起高度重视。  相似文献   

19.
Proteus sp. is able to catalyse the reversible transformation of crotonobetaine into L(-)-carnitine during aerobic growth. Contrary to other Enterobacteriaceae no reduction of crotonobetaine into gamma-butyrobetaine could be detected in the culture supernatants. Activities of L(-)-carnitine dehydratase, carnitine racemasing system and crotonobetaine reductase could be determined enzymatically in cell-free extracts of Proteus sp. Small amounts of gamma-butyrobetaine were found in cell-free extracts, indicating that it accumulates in the cell and inhibits the crotonobetaine reductase. Crotonobetaine and L(-)-carnitine were able to induce enzymes of carnitine metabolism. gamma-Butyrobetaine and glucose repress carnitine metabolism in Proteus sp. Other betaines are neither inducers nor repressors. Monoclonal antibodies against purified CaiA from Escherichia coli O44K74 recognise an analogous protein in cell-free extract of Proteus sp. No cross-reactivity could be detected with monoclonal antibodies against purified CaiB and CaiD from E. coli O44K74.  相似文献   

20.
Using a mini-Tn5lacZ1 reporter transposon, lacZ fusions have been identified in Proteus mirabilis that are activated by the accumulation of self-produced extracellular signals. Genes identified by this approach include putative homologs of pgm, nlpA and two genes of unknown function. The extracellular signal(s) involved in activation were resistant to the effects of acid and alkali. The signal required for activation of (nlpA) cma482::lacZ was sensitive to protease, suggesting the signal is a peptide or small protein. The signals behaved as polar molecules and were not extractable with ethyl acetate. A mini-Tn5Cm insertion was identified in a probable ptsI homolog that blocked activation of the cma134::lacZ fusion by an extracellular signal. The ptsI mutation did not alter extracellular signal production and may have a role in signal response.  相似文献   

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