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M Testa

Publications and source records attributed to M Testa.

At least 19 recordsLinked to original sources
PubMed2006

The stress tensor of a molecular system: an exercise in statistical mechanics.

We prove that conservation of the stress tensor is a consequence of the invariance of the partition function under canonical diffeomorphisms. From this observation a simple and general derivation of the formula which gives the local expression of the stress tensor of a molecular system in terms of its microscopic degrees of freedom readily follows. The derivation is valid in the canonical as well as the microcanonical ensemble. It works both in the classical and in the quantum mechanical settings and for arbitrary boundary conditions. In particular, if periodic boundary conditions are assigned to the system, the usual minimal-image prescription is naturally born out for mathematical consistency. An interesting outcome of our general analysis is that only in the case of a short-range interaction potential a truly local formula for the stress tensor can exist.

Journal Article↗
PubMed2006

Causes of anaemia in very low birth weight infants. Phlebotomy losses are not the first accused.

AIM: The specific aim of the study was to determine the correlation between the severity of pathology, the amount of blood removed for diagnostic purposes in the 1st week of life and the incidence of early anaemia in very low birth weight (VLBW) infants. METHODS: We recorded the level of haemoglobin (Hb) and haematocrit (Ht) in each of the 50 infants entered in the study at their admission in our neonatal intensive care unit (NICU) and at the age of 8 days. We quantified for each infant the blood drawn for clinical purpose during the 1(st)week of life, using microanalytic techniques for all types of analysis performed. Using the neonatal therapeutic intensive score system (NTISS) we divided all patients into 2 groups: group A= mild light pathology; group B= severe pathology. RESULTS: There was statistically significant difference between the percent decrease of Hb and Ht with reference to the birth weight in the 2 groups. Logistic regression analysis indicated a strong correlation (P = 0.009) between higher degree of illness severity and higher percent decrease of Hb and Ht. The difference due to the amount of phlebotomy losses was not significant. CONCLUSIONS: To our knowledge, this study is the first that strongly suggest that phlebotomy losses is not the main cause of anaemia in VLBW preterm infants in the 1st week of life, when a policy of strictly attention to the amount of blood removed is performed.

Age Factors↗
PubMed2003

3D analysis of posturo-kinetic coordination associated with a climbing task in children and teenagers.

The aim of this study was to characterize the modifications of the posturo-kinetic coordination during a climbing task as a function of postural and/or movement constraints in children (8-10 years) and adolescents (10-15 years). A 3D-analysis of forces was recorded for different movement amplitudes and types of holds. The results show the involvement of horizontal and vertical forces to maintain equilibrium during the steady state changes for different experimental groups. The contribution of horizontal and vertical forces changes in the course of movement realization. The vertical momentum (Iz) is mainly involved in the movement initiation: this role is mostly meaning for children. The horizontal momentum (Ih) is mainly involved in controlling equilibrium: this role is mostly meaning for adolescents.

Adolescent↗
PubMed2002

7-ketocholesterol in human and adapted milk formulas.

In the last few years, a variety of experimental and clinical studies concerning the formation, metabolism, and cellular effects of cholesterol oxidation products (COPs) have been carried out. Nevertheless, a substantial lack of knowledge exists regarding the possible intake of these compounds by the newborn through human and/or adapted formula milk. As far as the pathological role of COPs is concerned, exhaustive studies have shown that since dietary COPs are cytotoxic and atherotoxic, they may lead to adverse effects on health. The aim of this study was to investigate the possible development of cholesterol oxidation in adapted formula and in human milk by comparing the main cholesterol oxidation biomarker (7-ketocholesterol) concentration in both. To do so, the total (bonded and free) 7-ketocholesterol content was measured in ten fresh human mature milk samples and in ten milk adapted formula samples by high performance liquid chromatography and diode array detection. The 7-ketocholesterol human milk content (0.7+/-0.3) was often below the quantifiable limit (0.5 microg/g of extracted lipids) while 7-ketocholesterol adapted milk concentrations were often above (3.6+/-4.0) this limit. The 7-ketocholesterol content of adapted formula samples was significantly higher as compared to human milk samples (P<0.05). This is the first study to provide data concerning the concentrations of cholesterol oxides in human milk and in formula milk. Our results clearly suggest that the manufacturing technologies employed and the nutrient extractive sources play a crucial role in the development of cholesterol oxides in the end product. Careful surveillance has to be paid in order to avoid alteration of bioactive properties of nutrients and/or development of potentially toxic derivative compounds.

Cholesterol↗
PubMed2002

[Surgical treatment of Hashimoto's thyroiditis. Personal experience].

BACKGROUND: To report personal experience in the surgical treatment of Hashimoto's thyroiditis. METHODS. Eight patients (7 females, 1 male, mean age 48 years old) referred to our Institution with diagnosis of Hashimoto's thyroiditis have been studied. All patients were evaluated by determination of serum thyroid hormones and of anti-thyreoglobulin and anti-microsomal antibodies; ultrasound and scintigraphic scans of the gland were performed in all cases and a cytological examination of fine needle aspiration (FNAC) of the nodules was evaluated. Diagnosis of Hashimoto's thyroiditis was suspected on the basis of clinical and laboratory data and was confirmed by cytology and histology on surgical specimens. Preoperative FNAC showed a Hashimoto's thyroiditis with thyroid differentiated carcinoma in 3 cases (37.5%), Hashimoto's thyroiditis in 1 case and chronic thyroiditis in 4 cases (50%). Seven patients underwent surgery, while 1 patient received a medical treatment; we performed 6 total thyroidectomies and 1 hemithyroidectomy. Histology on surgical specimens confirmed the diagnosis of Hashimoto's thyroiditis in all cases; in 3 patients an associated papillary thyroid carcinoma was found. RESULTS: Postoperative mortality was absent; no major postoperative complications (laryngeal nerve paralysis or permanent hypocalcemia) were recorded. Only 2 mild transient hypocalcemias have been observed. CONCLUSIONS: Total thyroidectomy is the technique of choice in surgical treatment of Hashimoto's thyroiditis, a self-immune pathology which involves the whole gland and has a high correlation with differentiated thyroid carcinoma (37.5%). Total thyroidectomy warrants a radical and definitive control of the disease, without risk of relapse, with a low incidence of major complications, in experienced hands, and anyway lower than the morbility due to reinterventions.

Biopsy, Needle↗
PubMed2001

Physical training in patients with chronic heart failure enhances the expression of genes encoding antioxidative enzymes.

OBJECTIVES: We sought to determine whether the benefit of training for vasodilation in the skeletal muscle vasculature of patients with chronic heart failure (CHF) is likely to be caused at the molecular level primarily by increased nitric oxide (NO) production or decreased inactivation of NO. BACKGROUND: Physical training reverses endothelium dysfunction in patients with CHF, mediated by increased NO bioactivity. Some animal studies support a mechanism whereby training results in increased vascular NO levels by sustained transcriptional activation of the endothelial NO synthase (eNOS) gene, presumably due to shear stress. The mechanism has not been addressed in patients with CHF. METHODS: The steady state transcript levels for eNOS and two other shear stress regulated genes (angiotensin-converting enzyme [ACE] and prostacyclin synthase [PGI2S]) were measured in samples of skeletal muscle from patients with CHF before and after 12 weeks of training. Transcript levels were measured in the same samples for two genes encoding antioxidant enzymes, copper zinc superoxide dismutase (Cu/Zn SOD) and glutathione peroxidase (GSH-Px). Untrained patients served as controls. RESULTS: As expected, training significantly enhanced peak oxygen uptake in the patients with CHF. Training did not increase steady-state transcript levels for eNOS, ACE or PGI2S. In striking contrast, training increased the expression of the antioxidative enzyme genes by approximately 100%. CONCLUSIONS: Our results do not support a model of benefit from training by increased eNOS expression. However, the data are entirely consistent with the alternative hypothesis, that reduced oxidative stress may account for the increase in vascular NO-mediated vasodilation. Insight into the mechanism may be relevant when considering therapies for exercise-intolerant patients with CHF.

Aged↗
PubMed2001

Prediction of lymph node status by analysis of prognostic factors and possible indications for elective axillary dissection in T1 breast cancers.

OBJECTIVE: To identify those patients with T1 breast cancers with lower risk of nodal metastases who can safely be spared axillary dissection. DESIGN: Retrospective study. SETTING: University hospital, Italy. SUBJECTS: Review of clinical records and histopathological slides of 547 patients with T1 breast cancer, operated on between 1984 and 1997. MAIN OUTCOME MEASURES: Incidence of axillary metastases in relation to age, menopausal status, diameter and grade of tumour, vascular invasion, DNA ploidy, S-phase fraction and hormone receptor state, by univariate and multivariate analysis. RESULTS: Axillary metastases were present in 159 patients (29%). On univariate analysis, diameter of tumour 10 mm or less (pT1a/pT1b cancers), no vascular invasion, and grade 1 tumour were significantly correlated with a lower risk of nodal metastases, but only vascular invasion (p = 0.0001, odds ratio = 3.1) and diameter of tumour (p = 0.04, odds ratio = 1.6) were independent predictors on multivariate analysis. Among 34 pT1a/pT1b cancers, with low grade of tumour and no vascular invasion, only 2 (6%) had axillary metastases. When only one favourable predictive factor was associated with diameter of tumour of 10 mm or less, the incidence of axillary metastases ranged from 12% for 43 patients with grade 1 cancers to 13% for 76 patients with no vascular invasion. CONCLUSIONS: Axillary dissection may be avoided in pT1a and pT1b breast cancers (< or = 10 mm), with low grade of tumour or no vascular invasion. T1 breast cancers 10 mm or less in diameter should be treated by a two-step approach, first wide excision of the tumour and then axillary dissection or not depending on pathological examination of the primary tumour.

Adult↗
PubMed2001

Initial experience with laparoscopic adjustable gastric banding and pouch dilatation: two cases.

BACKGROUND: Late proximal pouch dilatation (LPPD) has occurred occasionally following gastric banding for morbid obesity. At present, laparoscopic conservative resetting and oversuturing of the band is considered the standard procedure for pouch dilatation without any important posterior component. METHODS: Two cases of LPPD are presented, which occurred in our initial experience with the Lap-Band, corrected via a laparoscopic approach. RESULTS: The reintervention was necessary in both patients, with conservative laparoscopic repositioning and oversuturing of the band in the first case and laparoscopic substitution of the gastric band in the second. We have not observed further complications, and weight loss has been maintained in a midterm outcome in both cases (30 and 18 months follow-up). CONCLUSIONS: LPPD can be corrected with a conservative laparoscopic surgical approach, without complications and negative functional effects on mid-term outcome.

Adult↗
PubMed2001

The impact of cancer treatment on quality of life outcomes for patients with localized prostate cancer.

PURPOSE: We evaluated the impact of localized prostate cancer treatment on general, cancer specific and symptom domains of quality of life for up to 5 years after diagnosis. MATERIALS AND METHODS: A total of 842 men from the Health Professionals Followup Study, diagnosed between 1993 and 1998, were included in cross-sectional analyses of quality of life associated with prostate cancer treatment. A subset of 146 men diagnosed after 1995 were followed prospectively. Quality of life was assessed with the Medical Outcomes Study Short-Form 36 Health Status Survey, Cancer Rehabilitation Evaluation System Short Form and University of California Los Angeles Prostate Cancer Index by mailed questionnaires. Primary treatment modality was taken from medical records and patient self-report. RESULTS: Significant treatment differences were observed in all quality of life measures, with the largest occurring in sexual, urinary and bowel symptoms. Bowel function was significantly worse in patients who received external radiation and brachytherapy compared with prostatectomy (p <0.05). Although they had better or equivalent urinary and sexual function (p <0.05), patients treated with external radiation, hormones or watchful waiting had lower generic quality of life scores in multiple domains compared with those who underwent prostatectomy. Patients who had brachytherapy had similar generic quality of life outcomes compared with prostatectomy in all domains. CONCLUSIONS: Our findings suggest that important differences in quality of life go beyond known physical symptoms associated with various prostate cancer treatment options, many of which involve making a trade-off. It is important for patients with prostate cancer and health care providers to consider these differences while making treatment decisions.

Adult↗
PubMed2001

The impact of husband physical aggression and alcohol use on marital functioning: does alcohol "excuse" the violence?

Alcohol has been posited to serve as an "excuse" for deviant behavior, including domestic violence. A recent study suggested that wives hold husbands less responsible for their aggressive behavior when husbands are problem drinkers. To replicate and extend this study, the independent and interactive effects of husband physical aggression and husband alcohol use on wives' marital satisfaction and thoughts of divorce were examined among newlywed couples (n = 387). Husband physical aggression had a significant negative effect on marital satisfaction and a significant positive effect on divorce ideation regardless of the measure of husband alcohol use employed. Alcohol dependence had a negative effect on satisfaction; however, in no case was there an interaction between alcohol and aggression. Results fail to replicate an earlier study supporting an excuse function of alcohol and suggest that alcohol does not mitigate the negative effects of domestic violence on marital functioning.

Adult↗
PubMed2000

Angiotensin II receptor subtypes in the skeletal muscle vasculature of patients with severe congestive heart failure.

BACKGROUND: Vascular remodeling occurs in the skeletal muscle of patients with severe congestive heart failure (CHF); this remodeling is mediated in part by increased activity of the renin-angiotensin system. Animal models suggest that in the vasculature, angiotensin II receptor type 2 (AT2-R) expression may be upregulated in pathological states associated with vascular remodeling. The therapeutic effects of an AT1-R antagonist may, therefore, be in part due to increased plasma angiotensin II levels, which stimulate AT2-R. However, whether AT2-R is expressed in the skeletal muscle vasculature of patients with severe CHF is unknown. METHODS AND RESULTS: The steady-state transcript levels of the AT1-R and AT2-R genes were analyzed by reverse transcription-polymerase chain reaction in RNA samples prepared from the skeletal muscle of 12 patients with severe CHF (f1.gif" BORDER="0">O(2)<10 mL. kg(-1). min(-1)) and 5 age-matched healthy subjects who underwent vastus lateralis biopsies. Human fetal skeletal muscle RNA served as a positive control for the expression of AT1-R and AT2-R gene transcripts. Transcripts from the AT1-R gene were detected readily in all samples. In contrast, transcripts from the AT2-R gene were only detected in fetal skeletal muscle samples and could not be detected in the skeletal muscle vasculature of healthy subjects or that of CHF patients, who were treated with either angiotensin-converting enzyme inhibitors or AT1-R antagonists. CONCLUSIONS: The AT2-R gene is not expressed in the skeletal muscle of patients with CHF. In the absence of detectable AT2-R gene transcripts, the AT2-R pathway is unlikely to contribute to the effects of AT1-R antagonists on the skeletal muscle vasculature in patients with severe CHF.

Angiotensin Receptor Antagonists↗
PubMed2000

The role of women's alcohol consumption in evaluation of vulnerability to sexual aggression.

The authors examined the impact of alcohol consumption on women's risk perceptions and intended behaviors in a hypothetical situation in which the potential for establishing a relationship with an attractive man was coupled with the potential for sexual aggression. Fifty-nine single women, ages 21-29, were randomly assigned to 1 of 3 beverage conditions: (a) alcohol (dose sufficient to raise blood alcohol level to .08); (b) placebo, in which they were led to believe that they had consumed alcohol but had not; or (c) no alcohol, in which they neither expected nor received alcohol. Compared with women in the no-alcohol condition, women in the alcohol condition (a) rated the male character in the vignette more positively, (b) anticipated less risk and more benefit resulting from a series of behaviors likely to facilitate the relationship while increasing sexual vulnerability (e.g., engaging in consensual sexual activities), and (c) anticipated greater involvement in those behaviors. The placebo appeared to exert similar but weaker effects.

Adult↗
PubMed2000

[Acute diverticulitis of the right colon. Report of 3 cases].

Three cases of acute diverticulitis of the right colon are described and a review of the international literature about this rare disease is made. Diverticulitis of the ascending colon is an uncommon disease which mimics appendicitis or perforated neoplasm. The correct diagnosis is rarely made, but can be suggested by signs and symptoms and confirmed by the barium enema. It should be treated conservatively, like left-colon diverticulitis. Isolated diverticula can be managed by simple excision and primary closure. Local resection may be necessary if the involved area is too large. Right hemicolectomy is performed when carcinoma is strongly suspected.

Acute Disease↗
PubMed2000

Induction of interleukin-1beta and interleukin-6 gene expression in hypoperfused skeletal muscle of patients with peripheral arterial disease.

BACKGROUND: A growing amount of data supports the role of inflammation in the pathophysiology of atherosclerotic diseases but the cellular source of cytokines has not been clearly identified. Cytokines could be produced by inflammatory cells, activated endothelial and smooth muscle cells, and by the tissue exposed to recurrent ischemia. Accordingly, we evaluated whether hypoperfusion induces gene expression of interleukin (IL)-1beta and IL-6 in the skeletal muscle of patients with peripheral arterial disease and critical limb ischemia. METHODS: Skeletal muscle biopsies were obtained, during a femoral-distal bypass, from normoperfused (control) and hypoperfused skeletal muscles in 8 patients. Gene expression was assessed by semiquantitative reverse transcriptase-polymerase chain reaction, using glyceraldehyde-phosphate-deydrogenase mRNA levels as a normalization factor. RESULTS: In the hypoperfused biopsies, the level of IL-1beta gene expression was significantly higher in all but 2 patients (mean upregulation > 8.8 fold, p = 0.043), and the level of IL-6 gene expression was significantly higher in all but 1 patient (mean upregulation > 23.7 fold, p = 0.031). CONCLUSIONS: We report that IL-1beta and IL-6 gene expression is markedly upregulated in hypoperfused skeletal muscle of patients with critical lower limb ischemia. To our knowledge this is the first report of a local activation of the inflammatory cascade at the level of hypoperfused skeletal muscle. This activation, which could worsen symptoms and tissue viability and be involved in the pathophysiology of reperfusion injury, might be considered as a therapeutic target. It remains to be investigated whether our results may also apply to coronary artery disease.

Aged↗
PubMed2000

Modulation of vascular endothelial gene expression by physical training in patients with chronic heart failure.

BACKGROUND: Abnormalities of the skeletal muscle vasculature, such as endothelial dysfunction and reduced microvascular density, can be reversed by physical training in patients with chronic heart failure. The molecular mechanisms that mediate the beneficial effects of physical training on the vascular endothelium are unknown. METHODS: Endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) gene expression in the skeletal muscle, peak oxygen consumption (VO2) and calf peak reactive hyperemia were measured before and after 12 weeks of supervised physical training in 10 patients with chronic heart failure. Five patients with heart failure of similar severity who did not participate in the training program served as controls. RESULTS: The effects of physical training on eNOS and VEGF gene expression were heterogeneous. eNOS gene expression increased 3-4 fold in 4 patients while it remained constant in 6 patients. VEGF gene expression increased significantly in all patients who were not treated with beta-adrenergic blockade and remained constant in all patients who were treated with beta-adrenergic blockade. In contrast, physical training increased peak VO2 and calf peak reactive hyperemia in all patients. Mean peak VO2 increased from 13.13 +/- 2.21 to 16.19 +/- 2.69 ml/kg/min (p < 0.001) and calf peak reactive hyperemia increased from 19.7 +/- 2.3 to 29.6 +/- 4.0 ml*min(-1)*100 ml(-1) (p < 0.001). CONCLUSIONS: A supervised program of physical training that consistently enhanced peak VO2 and vascular reactivity in patients with chronic heart failure increased or left eNOS and VEGF gene expression unchanged in skeletal muscle. Changes in vascular endothelial gene expression may contribute to the benefits of training on vascular endothelial function but are not solely responsible for these benefits.

Aged↗
PubMed1999

The role of hepatitis C and B virus infections as risk factors for severe liver complications following allogeneic BMT: a prospective study by the Infectious Disease Working Party of the European Blood and Marrow Transplantation Group.

BACKGROUND: Severe liver disease, including fulminant hepatic failure and venoocclusive disease can occur after bone marrow transplantation (BMT). The aim of our study was to assess risk factors for veno occlusive disease and severe liver disease occurring within 6 months from BMT. METHODS: A total of 193 consecutive patients from 15 BMT Centers were prospectively enrolled between January and June 1995. Data on donors and recipients before and after transplant were collected and included age, gender, alanine aminotransferase (ALT), hepatitis B (HBV), and hepatitis C virus (HCV) markers, hematological disease, status and type of BMT, conditioning regimen and graft versus host disease prophylaxis. Statistical analysis included univariate descriptive and multivariate analysis based on logistic regression on major end-points. RESULTS: Forty-three of 193 patients died during the study period, and liver disease was the main cause of death (13 of 43, 30%). Incidence of severe veno occlusive disease was 8%, fulminant hepatic failure 0.5% and 12% of cases had ALT >500 U/L (normal < or =42 U/L). A de novo HBV or HCV infection occurred in 3.2 and 7% of patients respectively. Predictive risk factors for life-threatening liver disease were: unrelated donors (relative risk=5.8, confidence interval=1.7-19.8) and abnormal BMT donor ALT (relative risk=6.3, confidence interval=1. 5- 25.5). CONCLUSIONS: This study indicates that ongoing or previous infection with HBV or HCV in donor or recipient is not an absolute contraindication for BMT. However, abnormal ALT levels in BMT donors were a significant predictor of potentially lethal liver complications. The occurrence of de novo HBV or HCV infection did not correlate with severity of liver disease observed in the first 6 months posttransplant. These findings should be carefully evaluated before disregarding HBV or HCV positive siblings with normal transaminase levels in favor of unrelated donors.

Adolescent↗