Biomedical subjects

M Giacometti

Publications and source records attributed to M Giacometti.

27 records · Page 2Linked to original sources

PubMed1996

Isolation of Mycoplasma conjunctivae from conjunctival swabs of Alpine ibex (Capra ibex ibex) affected with infectious keratoconjunctivitis.

Mycoplasma conjunctivae was isolated four times from the eyes of nine Alpine ibex (Capra ibex ibex) suffering from keratoconjunctivitis. The animals examined were affected in two different outbreaks in the Swiss Alps. Parasitological and bacteriological studies, including investigations for chlamydia and mycoplasmas, were performed. The results indicate that M. conjunctivae is the primary pathogenic agent causing infectious keratoconjunctivitis in this species.

Animals↗

PubMed1995

Platelet indices in athletes performing a race in altitude environment.

Physical activity could modify platelet count and platelet indices. Previous reports showed modifications after exercise linked to type and duration of sports performances. The shortage of studies in this field stems from the crucial methodological problem of EDTA (ethylenediaminetetraacetic acid)-dependent, mean platelet volume modifications: the published data on platelets count and indices were obtained by using a light-scattering system without standardization of the period elapsed from drawing to measurement. We present a study of platelet indices performed in athletes participating in an "extreme" performance, a race of 30 km in altitude (6,700 m of ascents and descents), using standardized measurement by an aperture-impedance instrument transferred in the field. The platelet count and mean platelet volume significantly increased in athletes, whereas platelet distribution width decreased. The mean initial values were 240.6*10(9)/L for platelet count, 8.79 fL for mean platelet volume, and 15.79% for platelet distribution width. The correspondent mean final values were 288.4*10(9)/L, 9.14 fL, and 15.48%. The modifications of platelet count and indices were always in the physiological reference range. The entity and the rapidity of platelet count and indices modifications suggest that the more probable source of variation is the recruitment of noncirculating pools of mature platelets. Strenuous exercise does not show abnormal changes of platelet parameters.

Adolescent↗

PubMed1995

[Seroepidemiologic investigations in the Alpine ibex (Capra i. ibex) of Piz Albris in the canton of Grigioni (Switzerland)].

Sero-epidemiological investigations in wild animals may allow to assess distribution of selected pathogens that sometimes seem to be involved in sanitary interrelationships between wild and domestic ungulates sharing the same areas. Serological studies were carried out to investigate the prevalence of antibody against 8 pathogens in Alpine ibex of Albris colony (Grisons, Switzerland). Investigated sera came from 89 animals shot by gamekeepers in 1990-1991. Antibody against smooth Brucella, Coxiella burnetti, Leptospira interrogans, Borrelia Burgdorferi, Mycobacterium paratuberculosis, BHV-1 and ovine-caprine lentiviruses were not detected in the tested sera. However, 31% of sera analysed were found to be positive for Chlamydia psittaci. Three sera showed high antibody titres ( > or = 1/128) suggestive of active infection in the animals. Any influence of Chlamydia psittaci in reproductive performance of free-ranging alpine ibex should be investigated through isolation of the agent. Results are discussed with reference to methods used and with epidemiological picture in Switzerland and were compared with results of serological investigations carried out in ibex in Italy and France.

Animals↗

PubMed1994

Cortisol, testosterone, and free testosterone in athletes performing a marathon at 4,000 m altitude.

Cortisol, testosterone, free testosterone and the ratio between free testosterone and cortisol (FTCR) were monitored in six athletes participating in a marathon starting at 3,860 and finishing at 3,400 m, having reached the top at 5,100 m altitude. Blood was drawn at sea level before the departure for the mountain area, after a week of acclimatization, immediately after the marathon and after a 24-hour recovery period from the run. Cortisol increased after acclimatization and especially after the marathon; it decreased to normal values after recovery. Testosterone decreased after acclimatization, especially after the run; it presented a partial recovery 24 h after the race. Free testosterone did not decrease after acclimatization and presented partial recovery. FTCR could also be useful for monitoring fitness, overtraining and overstrain in strenuous and ultraendurance exercise.

Adult↗

PubMed1994

Growth hormone and insulin-like growth factor I in athletes performing a marathon at 4000 m of altitude.

Human growth hormone (hGH) characteristically increases during physical exercise. In sports medicine, hGH changes have mostly been described in short-term performances under standardized laboratory procedures. We studied hGH and insulin-like growth factor I (IGF-I) under field conditions in 7 runners performing a marathon at 4000 m of altitude, to study the hormonal changes under extreme endurance effort and to evaluate the release of 22 kDa and 20 kDa monomers under these conditions, in comparison with a control group. The blood samples were taken at sea level, after 1 week of acclimatization, immediately after the run, and after a recovery of 24 h from the marathon. hGH was quantified by using a polyclonal method, a 22 kDa specific monoclonal method and a monoclonal method recognizing both 22 kDa and 20 kDa isoforms. A significant increase in hGH was noted using all methods after the marathon, followed by a significant decrease after recovery. Significant differences between athletes and controls were found only for the measurement after the marathon. No statistically reliable decrease of IGF-I was observed in athletes and controls. We obtained more limited hGH rises than previously described in athletes; the importance of lactate levels indicates that the use of physical exercise as a stimulation test for hGH should be closely standardized. The 20 kDa monomer and other hGH molecular forms played a limited role in the hormone increase: in our experience, elevation of hGH in heavy exercise corresponds mostly to the 22 kDa isoform. We suggest that the evaluation of hGH elevation in sports medicine could be accurately performed using specific 22 kDa monoclonal assays.

Adult↗

PubMed1989

Isolation of inhibin alpha-subunit precursor proteins from bovine follicular fluid.

Two proteins with structural characteristics similar to peptide sequences identified in the inhibin alpha-subunit precursor sequence have been isolated from bovine follicular fluid. A side-fraction from the purification of bovine follicular fluid inhibin with high levels of inhibin immunoactivity relative to its inhibin bioactivity was fractionated through a sequence of procedures which included triazine dye affinity and phenyl-Sepharose chromatography, gel permeation chromatography on Sephadex G-100, reverse phase HPLC, and preparative polyacrylamide gel electrophoresis. The first of the two proteins identified had a molecular mass of 25-26K under reducing and nonreducing conditions and a NH2-terminal sequence identical to that of 43K inhibin alpha-subunit and showed minimal activity (less than 2% activity) compared with bovine 31K inhibin in either the inhibin in vitro bioassay or the RIA. These data suggest that this protein is the alpha 1-166 sequence of the bovine inhibin alpha-subunit (designated alpha N-subunit), most likely released after processing of either the inhibin alpha-subunit precursor or the 43K alpha-subunit involved in the conversion of 58K to 31K inhibin. The other protein identified (designated pro-alpha C-subunit) has a molecular mass of 27K under nonreducing conditions and 20K and 6K under reducing conditions. It is inactive in the in vitro bioassay, although highly reactive in the inhibin RIA, and has NH2-termini identical to the pro sequence of the inhibin alpha-subunit precursor and the 20K alpha-subunit sequence. These results suggest that pro-alpha C is a disulfide-linked structure and may represent an intermediate in the dimerisation of alpha- and beta-subunits to form inhibin while the alpha N-subunit is probably a proteolytic product of either the alpha-subunit precursor or 58K inhibin.

Animals↗

PubMedDate not supplied

Detection of specific Mycoplasma conjunctivae antibodies in the sera of sheep with infectious keratoconjunctivitis.

The serological cross reactions between Mycoplasma conjunctivae, the etiological agent of infectious keratoconjunctivitis (IKC), and the antigenetically and phylogenetically closely related Mycoplasma ovipneumoniae, which is often found in sheep, were analysed. Cross reacting antigens were identified using sera from sheep with IKC and from sheep of herds known to be free of IKC, as well as rabbit hyperimmune serum specific to the two Mycoplasma species. Cross reactions were predominantly due to the strongly antigenic proteins of 42 kDa and 83 kDa. Serospecific antigens of M. conjunctivae could be separated from cross-reacting antigens by the extraction of Tween 20-soluble membrane proteins. The Tween 20-extracted proteins of the M. conjunctivae strain HRC/581T were used for the development of an indirect ELISA test. This ELISA test was shown to be a useful serological method for the diagnosis of M. conjunctivae infections and to identify infected sheep herds.

Animals↗

PubMedDate not supplied

[The ideal length of hospital stay in the surgical treatment of colorectal cancer].

In order to verify the safety of an ideal length of hospital stay (5-6 days) after open colectomy, we reviewed complications after 371 consecutive, elective colorectal resections for cancer at our institution between April 1991 and December 1998. Specifically, age of the patient, length of hospital stay and when the complication was diagnosed were registered. The median postoperative hospital stay was 9 days (range, 4-34 days). No difference in length of hospital stay was detected in patients < or = 65 years old versus > 65 years old (P = NS). All major complications (anastomotic leak, intestinal bleeding, intestinal occlusion, pneumonia, pulmonary embolism, pulmonary edema, stroke, angina pectoris, and fascial dehiscence) were diagnosed before the fifth postoperative day (P < 0.05). Among the minor complications (vomiting, packed red blood cells transfusion, diarrhea, wound infection, urinary tract infection, and pleural effusion), none requiring hospitalization was detected later then 5 days after the operation. We conclude that postoperative length of stay after colorectal resection for cancer can be reduced safely to five to six days after the operation.

Adult↗

PubMedDate not supplied

[Emergency surgery for complicated colorectal cancer. Retrospective study].

INTRODUCTION: Emergency surgery for the complications of colorectal cancer poses a significant surgical problem with published mortality rates as hight as 25% to 30%. We reviewed the results of the analysis and quantification of the influence of complications on the outcome of the patients who underwent emergency colectomy for colorectal cancer. MATERIALS AND METHODS: Retrospective study of the clinical features from, a series of 63 patients operated on from 1991 to 1997 (12% of all colorectal cancer operations in the same period). The correlations between complications and cancer stages were estimated by the KW (ANOVA method). RESULTS: Fifty-three patients underwent colorectal resection for intestinal occlusion (84%), 5 for perforation (8%) and 5 for lower gastrointestinal bleeding (8%). When the cancer complications were correlated to the different cancer stage at operation, the complications rate were 32%, 32%, and 36% in the stage II, stage III, and stage IV, respectively. This data was statistically significant: (KW = 58, p = 0.0001). The overall mortality rate was 8% (5 patients) and the total postoperative morbity rate was 32% (21 patients). The overall 5-year, 3-year, and 1-year survival was 47%, 48%, and 76% respectively. CONCLUSIONS: Emergency surgery for complicated colorectal cancer can be performed safely with low postoperative morbidity and mortality rate and can be advocated to realize both short and long-term survival rates comparable to elective surgery; the KW test supports the hypothesis that the a complication in the natural history of colorectal cancer doesn't correlate with the stage of disease.

Adult↗