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M Martini

Publications and source records attributed to M Martini.

At least 19 recordsLinked to original sources
PubMed1998

A case-control study on bovine tuberculosis in the Veneto Region (Italy).

A case-control study was undertaken to provide information about the role of some husbandry practices and farm characteristics in the epidemiology of bovine tuberculosis in the Veneto Region. Twenty-seven breeding herds where a positive result to the single intradermal cervical tuberculin test was confirmed by post-mortem examination were compared with seventy-four herds which had been free of the disease for at least three years. Epidemiological information was collected on farms. The factors taken into account in the study were chosen on the basis of their epidemiological plausibility and of the local livestock characteristics. Multiple logistic regression was applied to analyse the data. Factors identified as possibly involved in increasing the risk of bovine tuberculosis in the Veneto Region were the presence of mixed (dairy and beef) enterprises (OR = 4.9, P = 0.001) and of cattle purchase (OR = 5.8; P = 0.003). Other factors (such as herd size, housing system, summer mountain pasture, possible contact with wild animals, and indirect contacts with other herds) did not appear to significantly contribute to tuberculosis presence in this area. The results of this case-control study support the hypothesis that in the Veneto Region bovine tuberculosis infection is still associated with classical risk factors both (directly or indirectly) related to cattle movements.

Animal Feed↗
PubMed1998

Effects of ipriflavone on perialveolar bone formation.

The effect of ipriflavone (IP), a synthetic isoflavonoid derivative, on in vivo bone formation was studied in rat perialveolar bone by surgically producing a hole in the mandibular bone. The holes were filled either with powdered IP or with compounds containing no osteoinductive properties such as biostite and Htr (hard tissue replacement). In control animals, the holes were left to heal spontaneously. The animals were killed 3, 28, and 40 days after surgery and a detailed morphological and morphometric study was performed on the perialveolar bone surrounding the wounds. Three days after surgery (inflammatory phase) the bone wounds were occupied by hemorragic and inflammatory cells in both the untreated and IP-treated bone defects. Twenty-eight days after surgery, bone formation was evident with new bone spiculae particularly concentrated in the area of the bone lesion closest to the adjacent periodontal ligament. Morphometric measurements of the areas occupied by new bone showed that the synthesis of perialveolar bone was significantly stimulated by IP. The repair of the bone defects by new bone formation progressed by day 40, but only in the presence of IP were the original holes almost completely repaired. Conversely, biostite and Htr did not influence promotion of new bone formation. In conclusion, the results of the present study are consistent with a role of IP in stimulating osteogenesis and suggest that this compound could represent a potential therapeutic tool to promote repair of injured perialveolar bone.

Alveolar Process↗
PubMed1998

The effects of perilymphatic tonicity on endolymph composition and synaptic activity at the frog semicircular canal.

The effects of changes in perilymphatic tonicity on the semicircular canal were investigated by combining the measurements of transepithelial potential and endolymphatic ionic composition in the isolated frog posterior canal with the electrophysiological assessment of synaptic activity and sensory spike firing at the posterior canal in the isolated intact labyrinth. In the isolated posterior canal, the endolymph was replaced by an endolymph-like solution of known composition, in the presence of basolateral perilymph-like solutions of normal (230 mosmol/kg), reduced (105 mosmol/kg, low NaCl) or increased osmolality (550 mosmol/kg, Na-Gluconate added). Altered perilymphatic tonicity did not produce significant changes in endolymphatic ionic concentrations during up to 5 min. In the presence of hypotonic perilymph, decreased osmolality, K and Cl concentrations were observed at 10 min. In the presence of hypertonic perilymph, the endolymphatic osmolality began to increase at 5 min and by 10 min Na concentration had also significantly increased. On decreasing the tonicity of the external solution an immediate decline was observed in transepithelial potential, whereas hypertonicity produced the opposite effect. In the intact frog labyrinth, mEPSPs and spike potentials were recorded from single fibers of the posterior nerve in normal Ringer's (240 mosmol/kg) as well as in solutions with modified tonicity. Hypotonic solutions consistently decreased and hypertonic solutions consistently increased mEPSP and spike frequencies, independent of the species whose concentration was altered. These effects ensued within 1-2 min after the start of perfusion with the test solutions. In particular, when the tonicity was changed by varying Na concentration the mean mEPSP rate was directly related to osmolality. Size histograms of synaptic potentials were well described by single log-normal distribution functions under all experimental conditions. Hypotonic solutions (105 mosmol/kg) markedly shifted the histograms to the left. Hypertonic solutions (380-550 mosmol/kg, NaCl or Na-Gluconate added) shifted the histograms to the right. Hypertonic solutions obtained by adding sucrose to normal Ringer's solution (final osmolality 550 mosmol/kg) increased mEPSP and spike rates, but did not display appreciable effects on mEPSP size. All effects on spike discharge and on mEPSP rate and size were rapidly reversible. In Ca-free, 10 mM EGTA, Ringer's solution, the sensory discharge was completely abolished and did not recover on making the solution hypertonic. These results indicate that perilymphatic solutions with altered tonicity produce small and slowly ensuing changes in the transepithelial parameters which may indirectly affect the sensory discharge rate, whereas relevant, early and reversible effects occur at the cytoneural junction. In particular, the modulation of mEPSP amplitude appears to be postsynaptic; the presynaptic effect on mEPSP rate of occurrence is presumably linked to local calcium levels, in agreement with previous results indicating that calcium inflow is required to sustain basal transmitter release in this preparation.

Action Potentials↗
PubMed1998

Endotoxin-mediated intestinal damage: protective effect of capsaicin in the rat.

BACKGROUND: Endotoxin provokes the disruption of intestinal mucosal architecture. To investigate whether afferent fibers of the enteric nervous system are involved in this damage, we have used capsaicin to induce a selective, long-lasting degeneration of these fibers in the rat. METHODS: The rats were divided in two groups, receiving subcutaneously either capsaicin or its vehicle. After 10 days the rats from each group were injected with nonlethal doses of endotoxin or with saline. The next day all the animals were killed, and the jejunum and ascending colon were collected for light and scanning electron microscopy analysis; morphometric analysis of jejunal villus height was also performed. RESULTS: The rats receiving endotoxin but not pretreated with capsaicin had severe morphologic alterations and a significant reduction in villus height. In contrast, the rats pretreated with capsaicin and then with endotoxin showed a preserved mucosa with normal mean villus height. CONCLUSIONS: Capsaicin pretreatment is able to prevent endotoxin-induced damage of intestinal mucosa; this result seems to indicate that afferent fibers of the enteric nervous system are involved in the pathogenesis of this damage.

Animals↗
PubMed1998

Intraoperative endoscopy during colorectal surgery.

In cases where preoperative studies may have been inadequate or could not be performed, intraoperative endoscopy (IOE) becomes an essential investigative tool for identification of synchronous lesions, of nonpalpable lesions, of sources of bleeding, and localization of lesions during laparoscopic colonic surgery. We report our experience with IOE, and describe our techniques of transabdominal colonoscopy. A review of the IOE performed in hospitals affiliated with the University of Miami was done. Fifty-eight patients received IOE from July 1994 to August 1996. There were 47 colonoscopies (38 transanal and 9 transabdominal), and 11 flexible sigmoidoscopies. Colorectal cancer, diverticulitis, inflammatory bowel disease, and lower gastrointestinal bleeding represented 83% of cases. In 10% of cases IOE changed the extent of the surgical procedure. There were no complications related to IOE. We conclude that in selected patients undergoing colorectal procedures, IOE is an essential tool. It can be performed safely, effectively, and rapidly.

Adult↗
PubMed1998

Assessment of right ventricular function and interstitial fibrosis in idiopathic dilated cardiomyopathy: hemodynamic correlates and prognostic value.

BACKGROUND: Right ventricular (RV) function and morphometric quantitation of interstitial fibrosis in idiopathic dilated cardiomyopathy (IDC) have not been the subject of specifically designed clinical observations. In particular, their role in routine assessment and prognostic evaluation of patients (pts) with IDC remains to be settled. METHODS: Eighty-one consecutive IDC patients (63 M, 18 F; mean age 52 +/- 11 yrs) with left ventricular (LV) systolic dysfunction (angiographic ejection fraction - EF - < 55%), normal coronary arteries and no histologic evidence of myocarditis were studied. Cardiac catheterization and endomyocardial biopsy (EMB) were routinely performed in all cases. RV volumes and EF were obtained by angiography according to Ferlinz' method and interstitial fibrosis was quantitated by computer-assisted morphometric analysis. These data were analyzed in order to study correlations with hemodynamic parameters and to assess their prognostic value in a long-term follow-up. RESULTS: In the study population, right ventricular EF was significantly lower than in normal controls (35 +/- 11% vs 53 +/- 6%, p < 0.0001) and showed a significant positive correlation with LV EF (r = 0.54; p < 0.0001), and a weak but significant negative correlation with fibrosis (r = -0.29; p = 0.03). RV volumes, but not EF, were significantly related to mean pulmonary pressure. At multivariate analysis, RV end-diastolic volume (EDV) and EF were the two independent predictors of severe heart failure (NYHA class III-IV). After a mean follow-up of 64 +/- 36 months, 20 pts died and 9 had heart transplantation, for a 63% transplant-free survival rate (TFS). Multivariate analysis identified three independent predictors of TFS: LV stroke work index (p < 0.0001), RV stroke work index (p = 0.02) and RV EDV (p = 0.03). Fibrosis was predictive of survival only in the subgroup with LV EF < 20%. CONCLUSIONS: Assessment of RV function provides useful information in the evaluation of hemodynamic profile and prognosis of pts with IDC. Quantitation of interstitial fibrosis by morphometry provides little additional data.

Adult↗
PubMed1997

Leptospira interrogans serovar icterohaemorrhagiae seropositivity and the reproductive performance of sows.

The reproductive performance of 28 sows seropositive to Leptospira interrogans serovar icterohaemorrhagiae was compared with that of 87 Leptospira sp. seronegative dams belonging to the same herd. Sows were sampled during 1988 to 1993. During this period the herd was not submitted to any kind of intervention (antibiotic therapy, immunoprophylaxis or rodent control). Relative risks (RR) of return to heat, mummified fetuses, stillbirth, and weak newborn piglets for infected sows were assessed and the differences in means of total piglets born per litter, piglets born alive, piglets effectively housed, weaned piglets, stillbirths, mummified fetuses, weak newborn piglets, weight at birth of the piglets effectively housed, weight at 21 days of life and weight at weaning were evaluated. Seropositive dams had a greater risk of having weak newborn piglets (RR = 1.67, 1.02 < or = CI 95% < or = 2.72) and also of having more weak newborn piglets per litter (P = 0.01). Other variables examined were not different (P > 0.05).

Aging↗
PubMed1997

Peroxy radical oxidation of thymidine.

The peroxy radical (ROO) is unique among reactive oxygen species implicated in the production of DNA damage in that it possesses an extremely long half-life (order of seconds) and is predicted to have a relatively greater chemical selectivity in its reactions relative to other radical intermediates. Yet no product studies of the reactions of ROO with bases, nucleosides, or DNA have appeared, and thus no meaningful predictions can be made regarding its potential involvement in the production of DNA base damage and the mutagenic process. We report here on the reaction products formed by peroxy radical with thymidine, major target of oxidative base damage. ROO reacts with thymine to yield predominantly 5-Me oxidation products. The highly mutagenic 5-(hydroperoxymethyl)-2'-deoxyuridine, 5-formyl-2'-deoxyuridine, and 5-(hydroxymethyl)-2'-deoxyuridine are produced by peroxy radical oxidation. In contrast, 5Me oxidation products are minor products of thymidine oxidation by OH, which yields predominantly saturated derivatives via addition to the 5,6 double bound. A plausible mechanistic scheme for the formation of the base oxidation products of thymidine by peroxy radicals is presented. Attach at the deoxyribose moiety resulting in oxidative depyrimidination is also found to occur, as indicated by free base release. Phosphodiester backbone cleavage resulting in single and double strand breaks is also catalyzed by peroxy radical, as demonstrated using a plasmid nicking assay.

DNA Damage↗
PubMed1997

[Troponin T, Troponin I and CK-MB (mass) in the detection of periprocedural myocardial damage after coronary angioplasty].

The development of methods for the detection of circulating CK-MB mass, cardiac troponin T (cTn-T) and troponin I (cTn-I) has increased the diagnostic potential in the identification of myocardial damage. Coronary angioplasty (PTCA) represents a widely accepted revascularization procedure and a clinical model of induced ischemia. Using these new biochemical markers, we evaluated the incidence and the clinico-procedural correlates of minor myocardial damage (MMD) in a series of patients treated with PTCA in our Department. In 57 consecutive patients (75% males; mean age 58 years; range 35-80) undergoing elective PTCA from March 1 to June 30, 1995, serum levels of CK-MB mass, cTn-T and cTn-I were measured at baseline and at 6, 12 and 24 hours after the procedure. Seventy-eight coronary stenoses were dilated (mean 1.4 lesion/patient), 17 of these were in infarct-related vessels; 8 were total occlusions and 2 were located in saphenous vein grafts. Twenty-two procedures were completed by coronary stenting (17 elective). cTn-T and cTn-I were considered abnormal when serum levels were > 0.2 ng/ml and > 0.6 ng/ml, respectively. CK-MB mass was also determined in all patients (abnormal > 5 ng/ml). No patients had clinical or electrocardiographic evidence of myocardial infarction after the procedure. Overall, 16 patients (28%) developed biochemical evidence of post-procedural MMD (defined as the presence of at least one abnormal sample of any among the three markers tested). Four (7%) had abnormal CK-MB mass (at least one sample), 9 (16%) abnormal cTn-T, and 15 (26%) abnormal cTn-I. When CK-MB mass was elevated, both cardiac troponins were also elevated. In patients positive for MMD and abnormal CK-MB mass, peak cTn-I was significantly higher than in patients with normal CK-MB (3.02 +/- 1.07 vs 1.02 +/- 0.11 ng/ml; p = 0.009). The difference was not evident when comparing the same groups of patients for cTn-T (0.26 +/- 0.04 vs 0.18 +/- 0.10 ng/ml; p = 0.16). Also, peak cTn-I but not peak cTn-T had a positive correlation with peak CK-MB mass (r = 0.89; p < 0.0001 and r = 0.23; p = 0.40). The elevation of either marker of MMD was not related to clinical, angiographic or procedural variables. A possible interpretation for MMD was found in 2/3 of cases: bail-out (2); late occlusion (1); minor side branch occlusion (3); distal embolization from saphenous vein grafts (2) or total occlusions (2). In our series, MMD after PTCA occurs in 28% of cases and is unrelated to clinical, angiographic and procedural variables. Both cTn-T and cTn-I increase the sensitivity of CK-MB mass in the detection of MMD after PTCA, cTn-I being the most sensitive marker. In about 1/3 of cases, the presence of MMD remains unexplained. The prognostic implications of MMD are as yet undefined.

Adult↗
PubMed1996

The effect of clofilium, a K-channel blocker, on the electrogenic K secretion and the sensory discharge at the frog semicircular canal.

Potassium transport by dark cells produces marked K-concentration differences between endo- and perilymphatic fluids in labyrinthine organs and generates the transepithelial potential. The ensuing electrochemical potential for K sustains the transduction current which regulates activity at the cytoneural junction. Clofilium, a compound which is known to block cardiac K channels and to decrease the endocochlear potential, was applied to the endolymphatic side of the isolated frog semicircular canal. The drug abolished the transepithelial potential and increased K outflux from the lumen to the dark cells (or the basolateral perilymph) with no apparent interference with active K secretion. When applied to the perilymphatic side in the intact labyrinth, clofilium reduced the rate of occurrence of miniature excitatory postsynaptic potentials (mEPSPs), both at rest and in response to mechanical stimulation (sinusoidal rotation at 0.1 Hz, 12.5 deg/s2 peak acceleration). This effect may be related to a reduced K-electrochemical unbalance and a decreased transduction current. The drug consistently reduced mEPSP size, although amplitude distributions remained log-normal and time intervals between successive mEPSPs remained exponentially distributed; this suggests a direct effect of clofilium on the postsynaptic membrane, in addition to any possible presynaptic effects. Spike discharge by the afferent fibre was almost completely abolished at rest and responses to mechanical stimulation were reduced by 85-90%. These effects cannot be accounted for by the mild reduction of mEPSP rates and confirm a direct action of clofilium on the afferent postsynaptic terminal.

Animals↗
PubMed1996

An updating of the occurrence of canine heartworm disease in northern Italy.

A survey was carried out in northern Italy (Veneto and Friuli Venezia Giulia Regions) to assess the extension of canine heartworm disease close to the classic hyperendemic areas of the Po Valley. A filtration test on 275 privately owned dogs showed a mean prevalence of 44%, with a peak of 55% in the Venice province. A high prevalence (17%) of occult filariosis was discovered using a serological test. These values fall within the medium-high range previously reported from other Italian areas. The provinces of Pordenone, Udine, Trieste, Treviso and Belluno, where no cases had been previously reported, were found to be infected. The distribution of the infection did not differ significantly with the dogs' origin or sex. The prevalence seemed to be influenced significantly (p < 0.01) by the hosts' age, function and degree of outdoor activity, reflecting the different exposure risks.

Aging↗
PubMed1996

The host-parasite relationship in canine heartworm infection in a hyperendemic area of Italy.

From November 1990 to June 1991, 2273 Dirofilaria immitis were collected from 175 stray dogs euthanized in the province of Padua. The breed, sex, age and weight of each animal were noted. The worms were counted, sexed, differentiated as adults or fifth-stage larvae and weighed, and their length was measured. The host-parasite relationship in this epidemiological situation was characterized by a high prevalence (67%) together with a low intensity (19) and abundance (13). The frequency distribution of the parasites in the population of dogs followed a negative binomial pattern (k = 0.3177), showing a good, stable host-parasite relationship. The major risk of infection was in late July and August, some new infections being established in October and, maybe, in November. The majority of dogs that acquired new infections were young animals probably because of an immune response in older dogs. However, the prevalences increased (p < 0.01) in dogs from 1 to 5 years old, in shepherd and hunting dogs compared to the other breeds, and in large as opposed to small dogs. Microfilaraemia (range 1-1,883,000/ml) correlated, as a trend, with the number of adult filariae, which also correlated with the age and the weight of the dogs (p < 0.01). No significant correlations were found between the length or weight of the adult filariae and the data from dogs.

Aging↗
PubMed1996

The validity of some haematological and ELISA methods for the diagnosis of canine heartworm disease.

Examinations for heartworm (Dirofilaria immitis) were performed on 175 impounded dogs from a hyperendemic area of the Po Valley (Italy). Each blood sample was used with five haematological diagnostic methods (filtration, direct smear, modified Knott, clotted blood and capillary tube) and three commercial ELISA kits (PetChek, Diasystems, Uni-Tec). The results were compared with the true infection status obtained from post-mortem examination of the heart, pulmonary arteries, thoracic venae cavae and lungs. The prevalence of the infection by adult worms at necropsy was 63%. The sensitivity of the tests ranged from 60% (capillary tube) to 81% (Diasystems) and the specificity from 88% (filtration) to 98% (PetChek). The results of all the tests differed significantly (p < 0.01) from those obtained at necropsy. The sensitivity of the tests was also assessed with respect to the differing numbers of worms in the hosts. A positive correlation between the worm burden and the sensitivity was observed in all the tests. It is apparent that the ELISA methods were better able to detect cases with a low number of worms than the haematological tests.

Animals↗
PubMed1996

Assessment of functional liver mass and plasma flow in acromegaly before and after long-term treatment with octreotide.

Functional liver mass and functional liver plasma flow (FLPF) were assessed in 11 patients with clinical features of acromegaly by determining galactose elimination capacity (GEC) and extrarenal clearance of sorbitol, before and 5 to 7 months after treatment with the long-acting somatostatin analog, octreotide (150 to 600 micrograms/d in three subcutaneous injections). Growth hormone (GH) and insulin-like growth factor-I (IGF-I) levels, as well as liver size by ultrasound, were also recorded. Baseline GEC was increased in every patient but one, for a mean of 0.78 +/- 0.10 g/min (normal, 0.53 +/- 0.07; P < .01). At reevaluation after 5 to 7 months of octreotide treatment, a significant reduction of GEC was observed (0.62 +/- 0.08 g/min, P < .001). Changes of GEC paralleled those of GH (38.6 +/- 34.4 v 11.7 +/- 15.2 micrograms/L, P < .01) and IGF-I (5.0 +/- 1.7 v 2.7 +/- 2.2 U/ml, P < .001). Significant correlations were found between GEC and GH (r = .50, P < .05) and between GEC and IGF-I (r = .55, P < .01). FLPF, assessed by extrarenal clearance of sorbitol, was within the normal limit in all cases (0.98 +/- 0.19 v 0.97 +/- 0.12 L/min, NS) and remained normal after 5 to 7 months of octreotide treatment (0.99 +/- 0.11 L/min). Hepatic structure determined with ultrasonic scanning and conventional liver-function tests were basally normal in all patients, with a slight increase of liver volume in three cases. No change of biochemical and/or morphological features occurred during follow-up evaluation. The results support the hypothesis that GH and especially IGF-I enhance liver metabolic capacity; conversely, functional liver perfusion is largely independent of their actions. Our data also suggest that octreotide is unable to produce well-structured changes of liver circulation when administered long-term.

Acromegaly↗
PubMed1996

MRI study of a physiotherapeutic protocol in anterior disk displacement without reduction.

Disk displacement of the temporomandibular joint (TMJ) without reduction has been considered a fundamental pathophysiologic abnormality of the joint. In this paper there are supportive clinical and MRI evidence of a successful repetitive manipulative technique for the treatment of acute and chronic locking. In 1500 treated cases, documented on videotape, only five cases required surgical intervention. The success of the therapy was confirmed by 13 MRI images of the TMJ of patients with acute and chronic locking before and after therapy. In all cases the anteriorly dislocated disk in closing and opening position was recaptured and repositioned in a normal position in the temporomandibular fossa. Three complete cases are reported with complete clinical and MRI documentation.

Adult↗