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991.
992.
Novel plasmid-mediated beta-lactamase (TEM-10) conferring selective resistance to ceftazidime and aztreonam in clinical isolates of Klebsiella pneumoniae. 总被引:2,自引:22,他引:2
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J P Quinn D Miyashiro D Sahm R Flamm K Bush 《Antimicrobial agents and chemotherapy》1989,33(9):1451-1456
Two clinical isolates of Klebsiella pneumoniae from seriously ill patients in Chicago, Ill., have been identified as resistant to ceftazidime and aztreonam but susceptible to other cephalosporins. This unusual antibiogram was shown to be due to a novel plasmid-mediated beta-lactamase which readily hydrolyzed ceftazidime and aztreonam in addition to penicillins such as piperacillin and carbenicillin. This enzyme and its attendant resistance were transferred to Escherichia coli by conjugation on a 50-kilobase plasmid. Isoelectric focusing revealed a single beta-lactamase band with a molecular weight of 29,000 and an isoelectric point of 5.57 in the resistant isolates and transconjugants. The beta-lactamase inhibitors clavulanic acid and sulbactam restored beta-lactam susceptibility in the resistant isolates. Fifty percent inhibitory concentrations of clavulanic acid and sulbactam were 4.4 and 940 nM, respectively. DNA hybridization studies indicated that this enzyme, designated TEM-10, is related to well-established TEM-type beta-lactamases. However, the TEM-10 enzyme was inhibited by p-chloromercuribenzoate, in contrast to TEM-2 beta-lactamase. On the basis of substrate and inhibition profiles, the TEM-10 enzyme could be easily discriminated from TEM-5 and RHH-I beta-lactamases. 相似文献
993.
Symptom report in orofacial pain patients: relation to chronic pain, experimental pain, illness behavior, and personality. 总被引:1,自引:0,他引:1
A study was conducted to determine symptom report patterns in a heterogenous population of orofacial pain patients and to evaluate how symptom patterns relate to various dimensions of the human pain experience. Results indicated that symptoms frequently associated with chronic orofacial pain disorders can be described by four indices related to the temporomandibular joint (TMJ) and its movement; discomfort of and parafunctional activities related to the masticatory muscles; interference of pain with activities of daily living; and presence of orofacial pain unrelated to myogeneous or arthrogenous TMJ disorders. Of these four symptom indices, only the pain interference (symptom) index was related to clinical pain and illness behavior. None was related to personality. Two of the indices were influenced by diagnosis. Biomechanical symptoms and parafunctional activities appear to be insignificantly related to perceived pain intensity, pain responsiveness, illness behavior, or personality, but are related to diagnosis. The results indicated that relatively simple symptom checklists have potential utility in screening orofacial pain patients and in evaluation of treatment outcome. 相似文献
994.
Rebecca M. Thursfield Khayam Naderi Neil Leaver Mark Rosenthal Eric W.F.W. Alton Andrew Bush Jane C. Davies 《Journal of cystic fibrosis》2018,17(5):657-665
Background
Vitamin D has health benefits in many respiratory diseases but the evidence in CF is unclear. Induction of the antimicrobial peptides cathelicidin (LL37) and human-beta-defensin-2 (HBD-2) may be the mechanism of any benefit. We hypothesised that antimicrobial peptide levels would be decreased, and airway infection and inflammation greater, in CF children with vitamin D deficiency. The objective of the study was to explore relationships between vitamin D, LL37 and HBD-2, and airway infection, inflammation and physiology in children with CF.Methods
Bronchoalveolar lavage (BALF) and blood were obtained from children undergoing fibreoptic bronchoscopy. Serum vitamin D, BALF HBD-2 and LL37, cultured bacteria and inflammatory markers were measured. Clinical parameters were recorded.Results
113 patients with CF, 23 with non-CF chronic suppurative lung disease (CSLD) and 6 healthy controls were included. We found no relationship between serum vitamin D and BALF HBD-2 or LL-37. There were no differences in infective or inflammatory markers between vitamin D sufficient and deficient groups. Vitamin D deficient patients (<50?nmol/L) did not have a worse FEV1 (CF: 66 (58–71)% vs. 71.5 (61–76)%, ns; non-CF CSLD: 69 (36–88)% vs. 70 (62–95)%, ns).Conclusions
In the first bronchoscopic study exploring this question, we demonstrate that vitamin D deficiency is not associated with immunological, infective or clinical markers of disease severity in patients with CF or CSLD. 相似文献995.
996.
Pneumococcal soft-tissue infections: possible association with connective tissue diseases 总被引:2,自引:0,他引:2
M J DiNubile M A Albornoz R J Stumacher B L Van Uitert S A Paluzzi L M Bush S C Nelson A R Myers 《The Journal of infectious diseases》1991,163(4):897-900
Streptococcus pneumoniae is not a well-recognized cause of soft-tissue infections. In less than 4 years, 12 cases of pneumococcal soft-tissue infection were identified through discussions with infections disease subspecialists in the Philadelphia area. Principal sites of involvement included skin and fascia, tongue, epiglottis, thyroid, brain, and breast. Pneumococcal bacteremia was documented in six cases (50%); in three of these, pneumococci were also cultured from the involved soft tissues. In the cases in which bacteremia was not demonstrated, pneumococci were isolated from the infected sites. Six patients had connective tissue diseases, of which five were diagnosed as systemic lupus erythematosus. Four of these patients were receiving corticosteroids when their infections developed. Two additional patients were HIV-seropositive intravenous drug users. S. pneumoniae may be a more important cause of soft-tissue infections than previously appreciated, especially in patients with connective tissue diseases. 相似文献
997.
998.
A Bush C M Busst W B Knight J S Carvalho M L Rigby E A Shinebourne 《British heart journal》1990,63(5):300-303
Transposition of the great arteries is frequently complicated by the early onset of pulmonary vascular disease. It is difficult to measure pulmonary blood flow by the Fick principle because the pulmonary arteriovenous oxygen content difference is small and bronchial blood flow is increased in this condition. In eight patients (mean age 7.7 years, range 3 months to 29 years) with transposition of the great arteries mass spectrometry was used to measure oxygen uptake and predict pulmonary end capillary blood oxygen content. The effects of the bronchial circulation were studied by computer modelling. There was close agreement between pulmonary end capillary and pulmonary vein blood oxygen contents but the resultant percentage difference in arteriovenous content difference was significant (mean (SE of difference)) (14.5(3.8)%). The effect of the bronchial circulation was to give spuriously high estimates of pulmonary blood flow. The error was greatest when oxygen consumption was low and aortic blood was very desaturated. 相似文献
999.
Ten of 32 patients with primary ciliary dyskinesia syndrome (PCDS) also had other conditions. Five esophageal problems, 4 congenital heart disease, 2 scoliosis, and 4 miscellaneous and probably coincidental conditions were discovered. Additionally, a patient in this series, who has a normal heart, had a brother who died after surgery for complex congenital heart disease. In retrospect, he too probably had PCDS. The association of severe esophageal and cardiac disease with primary ciliary dyskinesia has not been described before. The diagnosis of PCDS may carry more implications than previously recognized. Pediatr Pulmonol. 1993; 16:9–12. © Wiley-Liss, Inc. 相似文献
1000.
Gulley ML; Eagan PA; Quintanilla-Martinez L; Picado AL; Smir BN; Childs C; Dunn CD; Craig FE; Williams JW Jr; Banks PM 《Blood》1994,83(6):1595-1602