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M Gavioli

Publications and source records attributed to M Gavioli.

11 recordsLinked to original sources
PubMed1998

Escherichia coli tol-pal mutants form outer membrane vesicles.

Mutations in the tol-pal genes induce pleiotropic effects such as release of periplasmic proteins into the extracellular medium and hypersensitivity to drugs and detergents. Other outer membrane defective strains such as tolC, lpp, and rfa mutations are also altered in their outer membrane permeability. In this study, electron microscopy and Western blot analyses were used to show that strains with mutations in each of the tol-pal genes formed outer membrane vesicles after growth in standard liquid or solid media. This phenotype was not observed in tolC and rfaD cells in the same conditions. A tolA deletion in three different Escherichia coli strains was shown to lead to elevated amounts of vesicles. These results, together with plasmid complementation experiments, indicated that the formation of vesicles resulted from the defect of any of the Tol-Pal proteins. The vesicles contained outer membrane trimeric porins correctly exposed at the cell surface. Pal outer membrane lipoprotein was also immunodetected in the vesicle fraction of tol strains. The results are discussed in view of the role of the Tol-Pal transenvelope proteins in maintaining outer membrane integrity by contributing to target or integrate newly synthesized components of this structure.

Bacterial Outer Membrane Proteins↗
PubMed1997

[Preoperative radiotherapy in cancer of the rectum. Our 5-year experience].

Since 1990, 41 patients with rectal carcinoma have been submitted to preoperative radiotherapy, which induced a shrinkage of the tumor, favouring its surgical resection. Besides, in 3 cases the operative specimens were tumor free, and a higher incidence of A and B 1 categories was found. Surgical results have been compared with an analogous group of 20 patients, where surgery was performed as a first procedure, then followed by radiotherapy in 9. No increase of postoperative complications was observed. While analysis of follow-up results demonstrates a decrease of tumour recurrence in patients with preoperative radiotherapy, no difference in survival was registered, because of the development of extra-pelvic metastases.

Adult↗
PubMed1996

TolA central domain interacts with Escherichia coli porins.

TolA is an inner membrane protein with three domains: a transmembrane N-terminus and periplasmic central and C-terminal domains. The interaction of TolA with outer membrane porins of Escherichia coli was investigated. Western blot analyses of cell extracts with anti-TolA antibodies indicated that TolA forms high molecular weight complexes specifically with trimeric OmpF, OmpC, PhoE and LamB, but not with OmpA. The interaction of purified TolA domains with purified porins was also studied. TolA interacted with OmpF, PhoE and LamB porins via its central domain, but not with either their denatured monomeric forms or OmpA. Moreover, the presence or absence of lipopolysaccharides associated with trimeric porins did not modify the interactions. These results suggest that the specific interaction of TolA with outer membrane porins might be relevant to the function of Tol proteins.

Amino Acid Sequence↗
PubMed1996

[A rare case of primary abdominal actinomycosis].

The authors describe a case of primary abdominal actinomycosis operated on because of peritonitis sustained by a tubo-ovarian abscess. They discuss the pathogenesis of the case: the patient had been on intrauterine device contraception till two months earlier and had been operated on for breast cancer. Preoperative diagnosis is quite impossible and only the microscopic observation of the specimen can show the causative agent. Surgical options are reported, stressing the need for an adequate period of antimicrobial therapy.

Abscess↗
PubMed1996

[Prosthesis and emergency surgery of hernia].

Use of prostheses in emergency surgery is a controversial issue due to the risk of infection. We report our experience with a series of 31 strangled hernias treated in emergency situations with a polypropylene (n = 29) or a vinyl (n = 2) sheath placed in a pre-peritoneal or retro-muscular position. There were three small bowel resections and 13 resections of the omentum for necrosis. There were no cases of infectious complications during the post-operative period. There were no recurrent hernias during the follow-up. The absence of any supplementary morbidity after emergency prosthesis is in agreement with the data in the literature. These results suggest that a prosthesis can be proposed for strangled hernias when the weakness of the parietal wall would compromise a conventional procedure. Excluded are cases with severe infection, including peritonitis by gangrenous perforation of an incarcerated loop and associated colonic resections.

Emergency Medicine↗
PubMed1995

[Effect of menstrual cycle on the immune response to surgical stress].

The Authors have studied the effects of different surgical interventions on some factors of humoral and cell-mediated immuno-competence: 112 premenopausal women, operated on mainly for benign conditions, have been considered in order to evaluate the influence of various phases of menstrual cycle on surgical immunosuppression. Two schemes were used to stratify the study sample: in the first analysis, we have subdivided the patients in 59 cases in perimenstrual phase (0 through 6 and 21 through 36 days from last menstrual period, LMP) and 53 in periovulatory (7-20 days from LMP). The second stratification relied on the hormone-dependent phases determined by the putative time of ovulation 14 days after LMP: 51 cases in follicular phase and 61 cases in luteal phase have been considered. Immune parameters have been evaluated before surgery and the day after intervention. The first comparison stresses the worst outcome of immune parameters in patients operated on in the perimenstrual period (CD4, activated lymphocytes and C3 have significantly reduced post-operatively). The second part of the study shows no significant difference in the two groups as to such parametres.

Adolescent↗
PubMed1990

[Progress in the evaluation of lymphatic involvement in cancer of the rectum: endoscopic rectal lymphoscintigraphy].

The preoperative evaluation of lymphatic spread in rectal cancer constitutes a considerable problem. A prospective study including 45 patients operated for rectal cancer, was carried out in order to assess the diagnostic value of a new technique: endoscopic rectal lymphoscintigraphy. The results of the preoperative assessment were compared with histological data according to Dukes' classification (Dukes A/B: 22 cases, Dukes C: 23 cases). Analysis of these results revealed the sensitivity (80%), specificity (73%) and accuracy (80%) of this new technique. If, combined with endorectal ultrasonography, rectal lymphoscintigraphy might play highly significant role in identifying the indications for local excisions of small tumours; similarly, the effect of preoperative radiotherapy might be more thoroughly assessed.

Adenocarcinoma, Mucinous↗
PubMed1988

[Acute pulmonary edema due to hyperperfusion: experimental observations in the dog].

A condition of acute pulmonary edema was obtained experimentally in the dog, perfusing the lower lobe of the left lung by a roller pump with compatible canine plasma. The edema develops contemporarily to the increase of pressure in the pulmonary artery and the interstitial tissue: it diffuses principally in the interstitial tissue, while after clamping the pulmonary veins it is observed also inside the alveoli.

Acute Disease↗
PubMedDate not supplied

[Primary transitional-cell carcinoma of the male anterior urethra].

Primary carcinomas of the male anterior urethra account for less than 1% of all urological carcinoma. The majority of these neoplasias develop of the posterior part of the urethra (proximal portion). The most common histotype is the squamous-cellular carcinoma. We have only found 4 other published reports of primary transitional carcinoma of the male anterior urethra. The paper discusses the diagnostic and therapeutic procedures employed in these rare cases.

Aged↗