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31.
A 36-year-old woman acquired severe human granulocytic anaplasmosis after blood transfusion following a cesarean section. Although intensive treatment with mechanical ventilation was needed, the patient had an excellent recovery. Disease caused by Anaplasma phagocytophilum infection was confirmed in 1 blood donor and in the transfusion recipient.  相似文献   
32.
Discovery of novel DNA gyrase B inhibitors remains an attractive field in the search for new antibacterial drugs to overcome the known bacterial resistance mechanisms. In the present study, we designed and synthesized novel ethylurea derivatives of 4,5,6,7‐tetrahydrobenzo[1,2‐d]thiazole‐2,6‐diamine, 2‐(2‐aminothiazol‐4‐yl)acetic acid, and benzo[1,2‐d]thiazole‐2,6‐diamine and evaluated their Escherichia coli DNA gyrase inhibition. The most potent DNA gyrase inhibitors in the prepared library of compounds were benzo[1,2‐d]thiazoles 32–34 , 36 , and 37 with IC50 values in the low micromolar range. The most promising inhibitors identified were evaluated against selected Gram‐positive and Gram‐negative bacterial strains. Compound 33 showed a MIC of 50 μM against an E. coli efflux pump‐defective strain, which suggests that efflux decreases the on‐target concentrations of these compounds.  相似文献   
33.
The article presents an autosomal dominant Currarino syndrome with incomplete penetrance in three out of four members of the same family. The mother had only a bony sacral defect and no other signs. In the older daughter, the syndrome was completely developed with presacral cystic teratoma, a sacral defect and abdominal discomfort. The younger daughter had no clinical or imaging features of the disease. The only son harboured presacral meningocele, urinary stenosis and a sacral defect. The daughter and son with developed variants of the syndrome were successfully operated on and are now symptom free.  相似文献   
34.
Molecular mechanisms of insulin resistance and associated diseases   总被引:24,自引:0,他引:24  
Insulin resistance is a state in which higher than normal concentrations of insulin are required for normal response. The most common underlying cause is central obesity, although primary insulin resistance in normal-weight individuals is also possible. Excess abdominal adipose tissue has been shown to release increased amounts of free fatty acids which directly affect insulin signalling, diminish glucose uptake in muscle, drive exaggerated triglyceride synthesis and induce gluconeogenesis in the liver. Other factors presumed to play the role in insulin resistance are tumour necrosis factor alpha, adiponectin, leptin, IL-6 and some other adipokines. Hyperinsulinaemia which accompanies insulin resistance may be implicated in the development of many pathological states, such as hypertension and hyperandrogenaemia. Insulin resistance underlies metabolic syndrome and is further associated with polycystic ovary syndrome and lipodystrophies. When beta-cells fail to secrete the excess insulin needed, diabetes mellitus type 2 emerges, which is, besides coronary heart disease, the main complication of insulin resistance and associated diseases.  相似文献   
35.
A stapes gusher is an alarming situation occurring during stapes surgery for mixed hearing loss. It is characterized by the sudden profuse flow of cerebrospinal fluid in the middle ear and external ear canal after opening the vestibule of the inner ear. An adult patient with unilateral stapes gusher is described; he was operated on both ears with a good hearing result on both sides. The stapes on the side with the cerebrospinal fluid leak was malformed, especially in the posterior crus--a finding which may suggest the possibility of a stapes gusher. The small-hole stapedotomy is a safe technique when dealing with a profuse cerebrospinal fluid leak, and it enables the closure of the leak with additional tamponade of the oval niche and the achievement of a good hearing result.  相似文献   
36.
37.
Tumour necrosis factor superfamily member 11 (TNFSF11) gene, that codes for receptor activator of nuclear factor-kappaB ligand, is one of the candidate genes for the genetic susceptibility to osteoporosis. As variations in the TNFSF11 gene promoter could alter its expression, the aim of the study was to evaluate the functional influence of three polymorphisms in the promoter and to investigate their association with bone mineral density (BMD) and biochemical markers in postmenopausal women. A total of 404 postmenopausal women were genotyped for the presence of TNFSF11 gene promoter polymorphisms -290C>T, -643C>T and -693G>C. Two common haplotypes, CCG and TTC, which occur in 44.3 and 49.3% of subjects respectively, were subjected to functional analysis. Amplified fragments were cloned into pGL3-basic reporter plasmid, which was co-transfected with pRL-TK plasmid into HEK293 cells. Dual luciferase reporter assay was performed. BMD and biochemical markers were measured. Reporter gene analysis showed significantly higher luciferase activity in CCG than in TTC haplotype (P=0.018). Both showed association with lumbar spine BMD (BMD-ls; P=0.005 and 0.007 for TTC and CCG respectively), whereas in femoral neck there was no association with BMD. In postmenopausal osteoporosis, association with BMD-ls was established in -290C>T, -643C>T and -693G>C (P values: 0.001, 0.041 and 0.013 respectively). Association with femoral neck BMD was shown in -693G>C (P=0.049). No association was found with biochemical markers in any of the groups. Our results suggest that in postmenopausal osteoporosis, TNFSF11 gene promoter polymorphisms -290C>T, -643C>T and -693G>C play a functional role in the genetic regulation of BMD.  相似文献   
38.
Alginate‐encapsulated HepG2 cells cultured in microgravity have the potential to serve as the cellular component of a bioartificial liver. This study investigates their performance in normal and liver failure (LF) human plasma over 6–8 h in a fluidized bed bioreactor. After 8 days of microgravity culture, beads containing 1.5 × 109 cells were perfused for up to 8 h at 48 mL/min with 300 mL of plasma. After exposure to 90% LF plasma, vital dye staining showed maintained cell viability, while a 7% increase in lactate dehydrogenase activity indicated minimal cell damage. Glucose consumption, lactate production, and a 4.3‐fold linear increase in alpha‐fetoprotein levels were observed. Detoxificatory function was demonstrated by quantification of bilirubin conjugation, urea synthesis, and Cyp450 1A activity. These data show that in LF plasma, alginate‐encapsulated HepG2 cells can maintain viability, and metabolic, synthetic, and detoxificatory activities, indicating that the system can be scaled‐up to form the biological component of a bioartificial liver.  相似文献   
39.
The Wnt pathway has a bifunctional role in bone mass regulation, influencing osteoblasts and osteoclasts. The Wnt pathway genes are therefore candidate genes for susceptibility to osteoporosis. In our study, we focused on the effects of polymorphisms in selected Wnt pathway genes: low-density lipoprotein receptor-related proteins 5 and 6 (LRP5 and LRP6), Dickkopf1 (DKK1), sclerostin (SOST), and β-catenin (CTNNB1). We genotyped 652 subjects for the following polymorphisms: A1330V in LRP5; I1062V in LRP6; E232K in DKK1; D32Y, G34V, and N287S in CTNNB1; and -1397_-1396insGGA in SOST. Bone mineral density (BMD) was also measured. The allele frequencies were as follows: for A1330V C:T = 87%:13%, for I1062V C:T = 20%:80%, and for -1397_-1396insGGA-:GGA = 64%:36%. The studied nucleotide changes in the DKK1 and CTNNB1 genes were shown not to be polymorphic. In a Slovenian population, no association was shown between lumbar spine and femoral neck BMD in A1330V (P = 0.151 and 0.243) and in I1062V (P = 0.209 and 0.405). We observed a difference between SOST genotypes, corresponding to an allele dose effect, which was borderline significant for lumbar spine and femoral neck BMD (P = 0.047 and 0.085); but this did not survive the adjustment for multiple testing. These results indicate that a larger sample size would be necessary to detect these subtle effects. Our results suggest that A1330V in LRP5, I1062V in LRP6, and -1397_-1396insGGA in SOST are not associated with BMD in the Slovenian population.  相似文献   
40.
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