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Biomedical subjects

S Brambilla

Publications and source records attributed to S Brambilla.

At least 19 recordsLinked to original sources
PubMed2006

Giant dipole resonance in the hot and thermalized 132Ce nucleus: damping of collective modes at finite temperature.

The gamma decay of the giant dipole resonance (GDR) in the 132Ce compound nucleus with temperature up to approximately 4 MeV has been measured, using the reaction 64Ni + 68Zn at E(beam) = 300, 400, and 500 MeV. The gamma and charged particles measured in coincidence with recoils are consistent with a fully equilibrated compound nucleus emission. The GDR width, obtained with the statistical model analysis, is found to increase almost linearly with temperature. This increase is rather well reproduced within a model including thermal shape fluctuations and the lifetime of the compound nucleus.

Journal Article↗
PubMed2006

Decommissioning procedures for an 11 MeV self-shielded medical cyclotron after 16 years of working time.

The present article describes the decommissioning of a compact, self-shielded, 11 MeV medical cyclotron. A Monte Carlo simulation of the possible nuclear reactions was performed in order to plan the decommissioning activities. In the course of the cyclotron dismantling, cyclotron components, shields, and floor concrete samples were measured. Residual activities were analyzed with a Ge(Li) detector and compared with simulation data. Doses to staff involved in the decommissioning procedure were monitored by individual TL dosimeters. The simulations identified five radioactive nuclides in shields and floor concrete: 55Fe and 45Ca (beta emitters, total specific activity: 2.29 x 10(4) Bq kg) and 152Eu, 154Eu, 60Co (gamma emitters, total specific activity: 1.62 x 10(3) Bq kg-1). Gamma-ray spectrometry confirmed the presence of gamma emitters, corresponding to a total specific activity of 3.40 x 10(2) Bq kg-1. The presence of the radioisotope 124Sb in the lead contained in the shield structure, corresponding to a simulated specific activity of 9.38 x 10(3) Bq kg-1, was experimentally confirmed. The measured dose from external exposure of the involved staff was <20 muSv, in accordance with the expected range of values between 10 and 20 muSv. The measured dose from intake was negligible. Finally, the decommissioning of the 11 MeV cyclotron does not represent a risk for the involved staff, but due to the presence of long-lived radioisotopes, the cyclotron components are to be treated as low level radioactive waste and stored in an authorized storage area.

Computer Simulation↗
PubMed2003

Prevention of venous thromboembolism in spinal surgery.

Deep vein thrombosis (DVT), and its most feared complication, pulmonary embolism (PE), still have a high incidence with high risk for patients' health. Proven prophylactic measures are available but are generally underused, and DVT is still considered the most common cause of preventable death among hospitalized patients. The rationale for prophylaxis of venous thromboembolism is based on the clinically silent nature of the disease, the relatively high prevalence among hospitalized patients and the potentially tragic consequences of a missed diagnosis. During the last 15-20 years, spine surgery has changed radically, developing into a well-defined area of specialist surgery, and some attention is now being given to DVT events in spine surgery. The incidence of DVT during spine surgery is not documented in the literature, because only case reports or retrospective studies are reported. It would therefore be very helpful to initiate a multicenter study in order to understand this problem better and to develop, if possible, some guidelines on prophylactic measures in spine surgery. In doing so, we need to consider each patient's pattern, any risk factors and every kind of surgical technique related to DVT, in order to improve the outcome of the patient and to reduce any medicolegal problems that could arise from a thrombotic complication or an epidural hematoma, with its high potential for irreversible consequences.

Humans↗
PubMed2000

Low frequency of elevated serum transferrin saturation in elderly subjects.

Serum transferrin saturation (TS) values were calculated on the basis of serum iron and transferrin (protein) measurements in a total of 2425 serum samples from six groups of subjects: individuals applying for selection as blood donors (M and F, median age 34 and 32 years); patients referring to the hospital laboratory for routine testing (M and F, median age 45 and 48 years); and elderly subjects living in a specialized institute (M and F, median age 76 and 82 years). In the first four groups the frequency of TS values <15% and >62% respectively, was substantially as expected, considering the average health conditions and sex. These results indirectly support the reliability of the measurement procedure. In the elderly group, however, the frequency of TS values >62% was zero. Mean TS values in the elderly group (males and females) were significantly lower (P<0. 0001) than in the blood donors group and in the hospital patients one. This observation suggests a shortened survival in the presence of (unrecognized) iron overload, pointing out at the usefulness of iron overload screening using simple biochemical tests.

Adult↗
PubMed2000

Effects of iron on extracellular and intracellular growth of Penicillium marneffei.

Killing of intracellular Penicillium marneffei conidia is demonstrated in gamma interferon-lipopolysaccharide-activated human THP1 and mouse J774 cells. Iron overload significantly reduces the antifungal activity of macrophages. Likewise, exogenous iron enhances and iron chelators inhibit the extracellular growth of P. marneffei. These results suggest that iron availability critically affects immunity to and the pathogenicity of P. marneffei.

Animals↗
PubMed1999

Antibody responses to hepatitis C virus hypervariable region 1: evidence for cross-reactivity and immune-mediated sequence variation.

Sequence heterogeneity of hepatitis C virus (HCV) is unevenly distributed along the genome, and maximal variation is confined to a short sequence of the HCV second envelope glycoprotein (E2), designated hypervariable region 1 (HVR1), whose biological function is still undefined. We prospectively studied serological responses to synthetic oligopeptides derived from HVR1 sequences of patients with acute and chronic HCV infection obtained at baseline and after a defined follow-up period. Extensive serological cross-reactivity for unrelated HVR1 peptides was observed in the majority of the patients. Antibody response was restricted to the IgG1 isotype and was focused on the carboxyterminal end of the HVR1 region. Cross-reactive antibodies could be readily elicited following immunization of mice with multiple antigenic peptides carrying HVR1 sequences derived from our patients. The vigor and heterogeneity of cross-reactive antibody responses were significantly higher in patients with chronic hepatitis compared with those with acute hepatitis and in patients infected with HCV type 2 compared with patients infected with other viral genotypes (predominantly type 1), which suggest that higher time-related HVR1 sequence diversification previously described for type 2 may result from immune selection. The finding of a statistically significant correlation between HVR1 sequence variation, and intensity, and cross-reactivity of humoral immune responses provided stronger evidence in support of the contention that HCV variant selection is driven by the host's immune pressure.

Adolescent↗
PubMed1999

Serum proteins by capillary zone electrophoresis: approaches to the definition of reference values.

The Paragon CZE 2000 (Beckman Analytical, Milan, Italy) is an automatic dedicated capillary zone electrophoresis (CZE) system, producing a five-zone serum protein pattern with quantitative estimation of the zones. With the view of substituting this instrument for two previously used serum protein electrophoresis techniques, we planned to produce reference values for the "new" systems leading to compatible interpretation of the results. High resolution cellulose acetate electrophoresis with visual inspection and descriptive reporting (HR-CAE) and five-zone cellulose acetate electrophoresis with densitometry (CAE-D) were the previously used techniques. Serum samples (n = 167) giving "normal pattern" with HR-CAE were assayed with the CZE system, and the results were statistically assessed to yield 0.95 reference intervals. One thousand normal and pathological serum samples were then assayed with the CAE-D and the CZE techniques, and the regression equations of the CAE-D values over the CZE values for the five zones were used to transform the CAE-D reference limits into the CZE reference limits. The two sets of reference values thereby produced were in good agreement with each other and also with reference values previously reported for the CZE system. Thus, reference values for the CZE techniques permit interpretation of results coherent with the previously used techniques and reporting modes.

Blood Proteins↗
PubMed1998

Dynamics of hypervariable region 1 variation in hepatitis C virus infection and correlation with clinical and virological features of liver disease.

Hepatitis C virus (HCV) infection is a dynamic process during which molecular variants are continuously selected as the result of virus adaptation to the host. Understanding the nature of HCV genetic variation is central to current theories of pathogenesis and immune response. We prospectively studied hypervariable region 1 (HVR1) variation in the E2 gene of 36 hepatitis C patients, including 10 asymptomatic carriers, followed up for 1 to 2 years. Sequence changes in single and consecutive serum samples were assessed and correlated with clinical and virological parameters of liver disease. A region of the E1 gene was sequenced for comparison in 3 subjects. HVR1 heterogeneity at single time points widely varied in individual patients, did not increase cumulatively over the follow-up period, and did not correlate with HVR1 evolutionary rates. Conversely, the process of HVR1 sequence diversification, although differed considerably among patients, was stable over time and directly correlated with infections by HCV type 2, lower alanine aminotransferase (ALT) levels, and absence of cirrhosis. HCV carriers showed the highest HVR1 variation rates. Our findings indicate that HVR1 variation has an adaptive significance and is associated with favorable features of liver disease and suggest that prospective, rather than static, observations are required to model the process of HCV variation.

Adult↗
PubMed1996

Hepatitis C virus genotypes and risk of hepatocellular carcinoma in cirrhosis: a case-control study.

BACKGROUND & AIMS: Viral genotypes have been associated with different severity and outcome of hepatitis C virus (HCV)-related liver disease. The aim of this study was to determine whether HCV genotypes may influence the cirrhosis-related risk of the development of hepatocellular carcinoma (HCC). METHODS: Three groups of patients were studied: 593 patients with chronic hepatitis, 166 patients with HCC and cirrhosis, and 219 patients with cirrhosis but without HCC. A cross-sectional study of frequency distribution and a case-control analysis were performed. HCV genotypes were detected according to Okamoto. RESULTS: HCV type 1b infection was more prevalent among patients with HCC compared with patients with cirrhosis but without HCC (P < 0.01) and chronic hepatitis (P < 0.001). Age, male sex, and HCV type 1b significantly influenced the risk of cancer in cirrhosis by univariate analysis. A pairwise comparison performed on 162 patients with HCC and an equal number of patients with cirrhosis matched by age, sex, and Child's class showed that HCV type 1b was independently associated with HCC (odds ratio, 1.7; P = 0.026). CONCLUSIONS: HCV type 1b is overrepresented in patients with cirrhosis and HCC and significantly influences the risk of HCC in cirrhosis, independent of sex, age, and Child's class.

Adult↗
PubMed1991

Operative treatment of cervicobrachialgia and vertigo due to uncovertebral joint arthritis.

In the field of cervical spondylosis, cervicobrachialgia caused by uncovertebral joint arthritis has been well defined and classified, as it is seen quite commonly in clinical practice. Non-operative treatment relieves the symptoms in most cases. Operative treatment is used when the neurovascular structures are involved and the patient does not respond to conservative treatment. The authors present the surgical technique they employed on 38 patients with neck and arm pain due to uncovertebral joint arthritis, and they report the long-term results.

Adult↗
PubMed1988

A case of isolated paralysis of serratus anterior.

The authors present a case of isolated paralysis of the serratus anterior due to compression of the long thoracic nerve by a cervical rib. The clinical and diagnostic features are described. Removal of the vertical rib resulted in complete functional recovery of the muscle involved.

Adult↗
PubMed1985

[1 year of traumatologic activity in the Emergency Orthopedic Unit of the G. Pini Institute (statistical data)].

The Authors have considered one year's traumatological activity in the G. Pini Institute's S.T.U. by drawing some statistical results. The data refer to the traumas ambulatorium-treated and to all those which required hospitalization during 1979. The total of the traumas surveyed in 1979 is 33335 of which 1812 required urgent hospitalization (5.44%). Previous statistics show 6679 patients in 1961 and 3209 in 1956. We can realize how these figures have increased in a few years (and in this abstract the different kinds of traumas are also highlighted) without any adjustment to the existing structures and equipment which are completely insufficient.

Contusions↗
PubMed1984

[Clinico-functional evaluation of patients operated for the removal of total prosthesis of the hip].

The authors report the clinico-functional results observed in 109 patients subjected to removal of a total hip replacement. After remarking the progressive increase in the aseptic mobilizations recorded during the last years, and after shortly stating the criteria whereby the prosthesized patients are controlled along with the time, they detailedly set forth the results. In conclusion, the results recorded are generally satisfactory, although the operation for removal of the replacement is an expedient badly fitting subjects in young or, anyhow, working age.

Equipment Failure↗
PubMed1984

[Physiopathology of uncarthrosis].

In the present work some concepts of physiopathology and pathogenesis of cervico-brachial neuralgiae due to uncoarthrosis are punctualized; after a short specification about diagnostics, the possibility of a surgical treatment is schematically represented.

Brachial Plexus Neuritis↗