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11.
Macrolide efflux genes mef(A) and mef(E) are carried by different genetic elements in Streptococcus pneumoniae 总被引:8,自引:0,他引:8 下载免费PDF全文
Del Grosso M Iannelli F Messina C Santagati M Petrosillo N Stefani S Pozzi G Pantosti A 《Journal of clinical microbiology》2002,40(3):774-778
Susceptibilities to macrolides were evaluated in 267 Streptococcus pneumoniae isolates, of which 182 were from patients with invasive diseases and 85 were from healthy carriers. Of the 98 resistant isolates, 20 strains showed an M phenotype and carried mef. Strains that carried both mef(A) and mef(E) were found: 17 strains carried mef(A) and 3 carried mef(E). The characteristics of the strains carrying the mef genes and the properties of the mef-containing elements were studied. Strains carrying mef(A) belonged to serotype 14, were susceptible to all the antibiotics tested except erythromycin, and appeared to be clonally related by pulsed-field gel electrophoresis (PFGE). The three mef(E) strains belonged to different serotypes, showed different susceptibility profiles, and did not appear to be related by PFGE. The sequences of a fragment of the mef-containing element, which encompassed mef and the msr(A) homolog, were identical among the three mef(E)-positive strains and among the three mef(A)-positive strains, although there were differences between the sequences for the two variants at 168 positions. In all mef(A)-positive strains, the mef element was inserted in celB, which led to impairment of the competence of the strains. In line with insertion of the mef(E) element at a different site, the competence of the mef(E)-positive strains was maintained. Transfer of erythromycin resistance by conjugation was obtained from two of three mef(A) strains but from none of three mef(E) strains. Due to the important different characteristics of the strains carrying mef(A) or mef(E), we suggest that the distinction between the two genes be maintained. 相似文献
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Neves Lia Mara Grosso Tim Carla Roberta Floriano Elaine Medeiros da Silva de Avó Lucimar Retto Fernandes João Batista Parizotto Nivaldo Antonio Cominetti Marcia Regina 《Lasers in medical science》2021,36(4):863-870
Lasers in Medical Science - Ultraviolet radiation (UVR) is the major etiologic agent of cutaneous photoaging, and different strategies are used to prevent and treat this condition. The... 相似文献
14.
Nicola De Stefano Victor Navarro-Tableros Dorotea Roggio Alberto Calleri Federica Rigo Ezio David Alessandro Gambella Daniela Bassino Antonio Amoroso Damiano Patrono Giovanni Camussi Renato Romagnoli 《Transplant international》2021,34(9):1607-1617
Livers from donors after circulatory death (DCD) are a promising option to increase the donor pool, but their use is associated with higher complication rate and inferior graft survival. Normothermic machine perfusion (NMP) keeps the graft at 37°C, providing nutrients and oxygen supply. Human liver stem cell-derived extracellular vesicles (HLSC-EVs) are able to reduce liver injury and promote regeneration. We investigated the efficacy of a reconditioning strategy with HLSC-EVs in an experimental model of NMP. Following total hepatectomy, rat livers were divided into 4 groups: (i) healthy livers, (ii) warm ischemic livers (60 min of warm ischemia), (iii) warm ischemic livers treated with 5 × 108 HLSC-EVs/g-liver, and (iv) warm ischemic livers treated with a 25 × 108 HLSC-EVs/g-liver. NMP lasted 6 h and HLSC-EVs (Unicyte AG, Germany) were administered within the first 15 min. Compared to controls, HLSC-EV treatment significantly reduced transaminases release. Moreover, HLSC-EVs enhanced liver metabolism by promoting phosphate utilization and pH self-regulation. As compared to controls, the higher dose of HLSC-EV was associated with significantly higher bile production and lower intrahepatic resistance. Histologically, this group showed reduced necrosis and enhanced proliferation. In conclusion, HLSC-EV treatment during NMP was feasible and effective in reducing injury in a DCD model with prolonged warm ischemia. 相似文献
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Panzera F Ghisio S Grosso A Vigezzi P Vitale M Cariaggi RM Mistrangelo M 《Minerva chirurgica》2000,55(7-8):489-492
BACKGROUND: The many advantages and extreme versatility made laparoscopic cholecystectomy (L.C.) the gold standard for symptomatic cholelithiasis. The aim of this research is a retrospective analysis of personal experience with laparoscopic cholecystectomy in a peripheral hospital compared with the literature on the subject. METHODS: Since June 1982, a total of 989 L.C. have been performed. The patients were: 691 (68.6%) women and 298 (29.4%) men with a mean age of 56 years (range 17-84). The indications were: 791 symptomatic cholelithiasis, 142 chronic cholecystitis, 45 empyema-hydrops and 11 adenomyomatosis. RESULTS: No postoperative death have been observed and the conversion rate was of 24 cases (2.3%). The main complications were 3 cases of injury of the biliary tract and 2 cases of postoperative bleeding (1 from cystic artery and 1 from the umbilical wound). Minor complications observed were 12 cases (1.2%) of infections of the umbilical wound and 3 cases of umbilical hernia (0.3%). The elevation of stasis index was observed in 3 cases which solved spontaneously. The length of stay was 2 days in 957 cases (97%), 8 days in 24 cases and 4-5 days in 8 (0.7%). CONCLUSIONS: No major trochar's lesions occurred, contrary to the percentages quoted in the literature (0.02%-0.9%). The selective use of the open technique and of the multiuse conic section trocar in the "closed" technique is suggested. The 3 cases of bile duct lesions did not occur during the training period, contrary to what quoted in the literature. In personal opinion, a careful surgical technique with a good Calot's triangle preparation, is necessary to prevent these inconveniences. Parietal complications (umbilical wound infections and laparocele) even if lesser than in the laparotomy technique, can be reduced by using the endobag and suturing the abdominal fascia of the 10 mm trocars. Moreover, the use of a systematic subhepatic drainage during the first 24 postoperative hours is suggested, since it can be useful to reveal possible bleeding. 相似文献
18.
Arsenio Spinillo Consultant Ezio Capuzzo Clinical Assistant Gaia Piazzi Registrar Federica Baltaro Registrar Mauro Stronati Consultant Alessandra Ometto Consultant 《BJOG : an international journal of obstetrics and gynaecology》1997,104(6):668-673
Objective To estimate the risk of specific adverse neonatal events resulting from the combined effects of prematurity and low birthweight in very preterm infants (delivered at 24–31 weeks of gestation)
Design A cohort study of specific adverse neonatal events in preterm infants born at between 24 and 31 weeks of gestation.
Setting Pavia, Italy.
Population Two hundred and thirty singleton infants with sonographically confirmed gestational age, delivered at 24 to 31 weeks of gestation.
Methods To evaluate the impact of a lower than expected birthweight on selected neonatal events independently of gestational age, we calculated birthweight standard deviation scores (differences between actual birthweight and fitted birthweight divided by fitted standard deviation) for each week of gestation.
Results After adjustment for gestational age and other confounders, there was a significant linear trend relating a decreasing birthweight SDS to an increased likelihood of neonatal death, intraventricular haemorrhage, severe respiratory distress syndrome, and acidosis. Compared with infants with SDS 0 ( 50th centile of birthweight), infants with birthweight SDS < −1 (< 16th centile) had increased odds for neonatal death [odds ratio (OR) 3.7, 95% confidence interval (CI) 1.42–9.6], grade III-IV intraventricular haemorrhage (OR 17.5, 95% CI 4.04–75.9), and neonatal acidosis (OR 3.22, 95% CI 1.41–7.4). The significance of birthweight SDS as a predictor of neonatal outcome, however, was lower than that of gestational age.
Conclusions A lower than expected birthweight affects the likelihood of several adverse neonatal events in very preterm infants. However, a decreasing birthweight SDS affects neonatal outcome less than decreasing gestation does. 相似文献
Design A cohort study of specific adverse neonatal events in preterm infants born at between 24 and 31 weeks of gestation.
Setting Pavia, Italy.
Population Two hundred and thirty singleton infants with sonographically confirmed gestational age, delivered at 24 to 31 weeks of gestation.
Methods To evaluate the impact of a lower than expected birthweight on selected neonatal events independently of gestational age, we calculated birthweight standard deviation scores (differences between actual birthweight and fitted birthweight divided by fitted standard deviation) for each week of gestation.
Results After adjustment for gestational age and other confounders, there was a significant linear trend relating a decreasing birthweight SDS to an increased likelihood of neonatal death, intraventricular haemorrhage, severe respiratory distress syndrome, and acidosis. Compared with infants with SDS 0 ( 50th centile of birthweight), infants with birthweight SDS < −1 (< 16th centile) had increased odds for neonatal death [odds ratio (OR) 3.7, 95% confidence interval (CI) 1.42–9.6], grade III-IV intraventricular haemorrhage (OR 17.5, 95% CI 4.04–75.9), and neonatal acidosis (OR 3.22, 95% CI 1.41–7.4). The significance of birthweight SDS as a predictor of neonatal outcome, however, was lower than that of gestational age.
Conclusions A lower than expected birthweight affects the likelihood of several adverse neonatal events in very preterm infants. However, a decreasing birthweight SDS affects neonatal outcome less than decreasing gestation does. 相似文献
19.
Early ovarian cancer: Is there a role for systematic pelvic and para-aortic lymphadenectomy? 总被引:1,自引:0,他引:1
Baiocchi Raspagliesi Grosso Fontanelli Cobellis di Re & di Re 《International journal of gynecological cancer》1998,8(2):103-108
Baiocchi G, Raspagliesi F, Grosso G, Fontanelli R, Cobellis L, di Re E, di Re F. Early ovarian cancer: Is there a role for systematic pelvis and para-aortic lymphadenectomy? Int J Gynecol Cancer 1998; 8 : 103–108.
In order to focus on the incidence and the clinical significance of lymphatic spread in patients with cancer apparently confined to the ovaries, we present our 20 year experience in a large series of patients with early ovarian cancer who had systematic pelvic and para-aortic lymphadenectomy. A retrospective study of 280 consecutive patients is presented. Systematic pelvic and para-aortic lymphadenectomy was performed in 205 cases (73.2%). Selective sampling and node biopsy were performed in 30 (10.7%) and 7 (2.5%), respectively. Node metastases were found in 32/242 patients (13.2%). The incidence of metastatic nodes was significantly higher in patients with serous adenocarcinomas and/or poorly-differentiated tumors. When few nodes were involved (1–3) lymphatic spread was most ipsilateral to the tumor. Even though the retrospective nature of the study has to be considered, univariate analysis revealed statistically significant differences in 5-year survival based on FIGO stage, histology, grade of differentiation, and node status. By contrast, using multivariate analysis, none of these risk factors was an independent variable for predicting long-term survival. However, node status closely approached the statistically significant level ( P = 0.06). Only prospective and randomized studies can clarify the role of lymphadenectomy in early ovarian cancer. However, while awaiting these results, this surgical procedure should be a part of a research protocol. 相似文献
In order to focus on the incidence and the clinical significance of lymphatic spread in patients with cancer apparently confined to the ovaries, we present our 20 year experience in a large series of patients with early ovarian cancer who had systematic pelvic and para-aortic lymphadenectomy. A retrospective study of 280 consecutive patients is presented. Systematic pelvic and para-aortic lymphadenectomy was performed in 205 cases (73.2%). Selective sampling and node biopsy were performed in 30 (10.7%) and 7 (2.5%), respectively. Node metastases were found in 32/242 patients (13.2%). The incidence of metastatic nodes was significantly higher in patients with serous adenocarcinomas and/or poorly-differentiated tumors. When few nodes were involved (1–3) lymphatic spread was most ipsilateral to the tumor. Even though the retrospective nature of the study has to be considered, univariate analysis revealed statistically significant differences in 5-year survival based on FIGO stage, histology, grade of differentiation, and node status. By contrast, using multivariate analysis, none of these risk factors was an independent variable for predicting long-term survival. However, node status closely approached the statistically significant level ( P = 0.06). Only prospective and randomized studies can clarify the role of lymphadenectomy in early ovarian cancer. However, while awaiting these results, this surgical procedure should be a part of a research protocol. 相似文献
20.
Nocturnal frontal lobe epilepsy (NFLE) has become clinically relevant in recent years. NFLE represents a spectrum of clinical manifestations, ranging from brief, stereotyped, sudden arousals, often recurring several times per night, sometimes with a quasi-periodic pattern, to more complex dystonic-dyskinetic seizures and to prolonged "somnambulic" behaviour. Episodes of increasing intensity have been labelled as paroxysmal arousal (PA), nocturnal paroxysmal dystonia (NPD) and episodic nocturnal wandering (ENW). NFLE affects both sexes with a higher prevalence for men, is frequently cryptogenetic and displays a strong familial trait for parasomnias and epilepsy (NFLE). Seizures appear more frequently between 14 and 20 years of age, but can affect any age and tend to increase in frequency during life. Interictal and ictal scalp electroencephalography (EEG) are often normal, the use of sphenoidal leads may be helpful. Carbamazepine taken at night is often effective at low doses, but a third of the patients are resistant to anti-epileptic drugs (AED) treatment. A familial form, characterized by an autosomal dominant transmission, has also been described. Autosomal dominant nocturnal frontal lobe epilepsy is a genetic variant of NFLE, in itself both clinically and biologically heterogeneous. NFLE should be suspected in the presence of frequent stereotyped paroxysmal nocturnal motor events arising or persisting into adulthood. Videopolysomnography is mandatory to confirm the diagnosis. 相似文献