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Biomedical subjects

M Braga

Publications and source records attributed to M Braga.

At least 73 records · Page 4Linked to original sources
PubMed1996

Viewing distance variation and related ophthalmological changes in office activities with and without VDUs.

This experimental study was conducted on 14 volunteer female clerks to measure viewing distance variation and related ophthalmological changes in office activities with (session 1) and without (session 2) VDU. A video camera connected to an electronic elaborator was used to determine eye-screen distance of the VDU operators during the task. Before and after each of the two work sessions far refraction, far phorias, near point of accommodation (APP), and fusional convergence were measured. Blinking rate of each subject was measured by a transducer only during the "VDU session'. The objective measurements of the eye-screen distance, whose range was between 48.42 and 65.33 cm, allowed a precise quantification of the occupational visual load during session 1. The accommodation was about 1.5-2D on average and the fusional convergence 10-13 delta on average. The symptomatology shows a number of disturbances in session 1 (71.4%) clearly higher than in session 2 (35.7%). The study of refraction before and after the task has shown a slight excess of accommodation compared to the theoretical value in both sessions, more marked in session 1. The APP shows no statistical significative variation. A tendency to exophoria was registered at the beginning and at the end of the trial and the fusional convergence clearly decreased, especially in the first session.

Accommodation, Ocular↗
PubMed1996

No difference between micro- and macroprolactinomas in the prolactin responsiveness to metoclopramide and dopamine administration.

Differences between micro- and macroprolactinomas, as regards the prolactin secretory pattern in response to pharmacological challenges, have been reported in in vivo and in vitro models, and interpreted as being due to different dopaminergic regulation of prolactin release. In 32 patients with prolactin-secreting tumors, 19 with microprolactinomas and 13 with macroprolactinomas, and ten healthy volunteers, we evaluated the prolactin secretion in response to pharmacological manipulations of central dopaminergic tone. To this end, three tests were performed, in random order: (1) 4-h saline infusion; (2) 10 mg metoclopramide as i.v. bolus; (3) 4-h dopamine infusion (0.01 microgram/kg/min) with a 10-mg metoclopramide bolus given after the second hour of infusion. Dopamine infusion, compared to saline, caused a significant prolactin decrease in all the three groups of subjects, without significant difference between micro- and macroprolactinoma patients. In prolactinoma patients, administration of metoclopramide induced a significant rise in plasma prolactin which, however, was significantly lower than the one displayed by controls. Again, no difference was observed between the two groups of hyperprolactinemic patients. Dopamine infusion induced a significant and comparable increase in the prolactin response to metoclopramide in micro- and macroprolactinoma patients, while it was ineffective in control subjects. In conclusion, no differences appear to exist between micro- and macroprolactinoma patients as regards the prolactin secretory pattern during pharmacological modifications of the dopaminergic tone. A central dopaminergic defect and an increased prolactin turnover with attendant reduction of the intracellular hormone pool may both be involved in the reduced prolactin release following provocative stimuli in patients with prolactinoma.

Adolescent↗
PubMed1996

Immune and nutritional effects of early enteral nutrition after major abdominal operations.

AIM: To investigate the effect of early postoperative enteral nutrition enriched with arginine, RNA and omega-3 fatty acids on immunological and nutritional variables after elective curative operations for gastric or pancreatic cancer. DESIGN: Randomised controlled trial. SETTING: University hospital, Italy. SUBJECTS: 78 Consecutive patients who were to undergo curative operations for gastric or pancreatic cancer, 60 of whom were suitable for the study. INTERVENTIONS: Patients were randomly allocated to three groups (n = 20 each) according to the type of postoperative nutritional support: standard enteral diet, the same diet enriched with arginine, RNA, and omega-3 fatty acids or total parenteral nutrition. The daily nutritional goal was 25 kcal (105 kJ)/kg and 0.25 g nitrogen/kg for all patients. MAIN OUTCOME MEASURES: Serum concentrations of immunoglobulins, albumin, transferrin, prealbumin, retinol binding protein (RBP); cholinesterase activity, weight loss, duration of operation, operative blood loss; blood transfusion; delayed hypersensitivity responses, number of lymphocyte subsets, phagocytic ability of monocytes, number of interleukin-2 (IL-2) plasma receptors, interleukin-6 (IL-6) plasma concentrations, postoperative infections and sepsis scores. RESULTS: All enterally fed patients but one completed the nutritional programme. There were significant postoperative reductions in both nutritional and immunological variables in all groups. On postoperative days 4 and 8 prealbumin concentration (p < 0.05), RBP concentration (p < 0.05), delayed hypersensitivity responses (p < 0.05), phagocytic ability of monocytes (p < 0.01) and concentration of IL-2 receptors (p < 0.009) had all recovered more in the group receiving the enriched solution. There was no difference in the postoperative infection rates among the three groups, but the infections were less severe in the enriched group (p < 0.005). CONCLUSION: Early enteral feeding was well tolerated. Patients who received the enriched solution recovered both their nutritional and immunological status quicker than those in the other two groups.

Adult↗
PubMed1996

[Conservative surgery in the environment of a screening program for breast carcinoma: evaluation of the results in terms of local recurrence].

This report evaluates the results of conservative surgery plus radiotherapy (QUART) in a group of 123 patients from the screening programme of the District Health Board USSL 41 in Brescia, Italy (over 250 tumours diagnosed in two screening rounds, between 1987 and 1993). To date no recurrence of neoplasms in the operated breast have been diagnosed in either of the two QUART groups (64 patients from the first round, average follow-up 28 months, median 66 months; 59 patients from the second round, average follow-up 28 months, median 30 months). A new carcinoma in the contralateral breast occurred in 3 patients (2 from the first and 1 from the second round), while in 3 cases there was a recurrence in another site (2 from the first and 1 from the second round). These results confirm both the proven effectiveness of conservative treatment in the local control of breast tumours, and the importance of the correct choice of conservative treatment in optimising aesthetic and therapeutic results.

Breast Neoplasms↗
PubMed1996

[Thyroid carcinoma in hyperthyroid syndromes].

The relationship between hyperthyroidism and carcinoma of the thyroid is still uncertain. The incidence of thyroid carcinoma ranges from 0.3 to 16.6%. Between 1984 and 1994 the Authors observed 9 patients affected with thyroid cancer and toxic nodular goiter (4 patients) or Basedow disease (2 patients) or scintigraphic evidence of single hyperfunctioning nodule (3 patients). Six out of the 9 cases were diagnosed as papillary cancer, while three as follicular cancer. A carcinoma was diagnosed before operation in only one case, while in the other 8 patients, the diagnosis was obtained by histological examination of the specimen. Four patients underwent subtotal thyroidectomy, while five patients underwent radical lobectomy. All patients are alive and in good health; the average follow-up was 48 months.

Adenocarcinoma, Follicular↗
PubMed1996

A simplified procedure for thromboplastin calibration--the usefulness of lyophilized plasmas assessed in a collaborative study.

The International Sensitivity Index (ISI) of thromboplastins is determined by calibration using fresh plasmas from 60 patients stabilized on oral anticoagulants and 20 healthy subjects. This procedure is demanding, particularly for those who have no easy access to patients. The alternative use of a smaller number of lyophilized plasmas has already been considered, but one important issue, the number of repeated measurements to be carried out, has never been addressed. Two commercial rabbit thromboplastins, A and B, were calibrated in 3 laboratories against CRM 149R. On each of 10 working days, prothrombin times were measured for a different set of 8 fresh plasmas and for the same set of 8 lyophilized plasmas. The ISI values for both thromboplastins were estimated by orthogonal regression on fresh and lyophilized plasmas. The between- and within-laboratory CV values of the estimated ISI were taken as measures of precision of the calibration. In addition, ISI and CV were calculated daily on cumulative results obtained with lyophilized plasmas from day 1 to day 10. The ISI values for both thromboplastins calculated with lyophilized plasmas were not significantly different from those with fresh plasmas (mean of 3 laboratories: 1.42 vs 1.48 for A and 1.22 vs 1.20 for B). The between-laboratory precision of the calibration with lyophilized plasmas was not considerably different from that with fresh plasmas (CV for 3 labs: 5.2% vs 6.8% for A and 0.9% vs 2.2% for B). The ISI estimated with lyophilized plasmas on results of day 1 were not different from those of days 2 through 10. Good within-laboratory precision of the calibration (CV around 2%) was already achieved on day 3. In conclusion, this study shows that lyophilized plasmas pooled from normals and patients on oral anticoagulants can be used as substitutes for individual fresh plasmas to simplify the existing procedure for thromboplastin calibration.

Anticoagulants↗
PubMed1996

Cancer incidence in 854 kidney transplant recipients from a single institution: comparison with normal population and with patients under dialytic treatment.

In this retrospective historical study, we compared the incidences of malignancies observed among 854 renal transplant recipients (RT) with at least 1 yr of follow-up, with the incidences of neoplasias among patients under regular dialytic treatment (RDT) and a control population from Northern Italy. Cox's proportional hazard model was used in RT recipients in order to evaluate the prognostic factors related to the development of neoplasia. Seventy six out of 854 RT patients (8.9%) developed some malignant neoplasia: 46% of these 76 were cutaneous neoplasias including melanomas, and the remaining 54% non cutaneous cancers: 33% miscellaneous tumors (MT), mostly adenocarcinomas, 17% Kaposi's sarcomas (KS), 4% non-Hodgkin's lymphomas (NHL). Malignancies had a higher incidence (p < 0.01) among RT recipients than among control and RDT patients. However, MT were equally frequent among the three groups. RDT patients on the contrary, had similar incidence of neoplasias when compared to the control population, but showed a lower incidence of squamous cell carcinomas (SCC). The risk ratios (RR) for the most frequent neoplasias among RT recipients vs. control population were: 224.7 for KS, 7.4 for NHL, 6.2 for SCC, 5.7 for basal cell carcinomas (BCC), 4.0 for MT. The risk of developing a de novo neoplasia was of about 13% at 10 yr and of 34% at 20 yr. In RT recipients, Cox's proportional analysis showed that age > 40 at transplantation and male sex were the only risk factors associated with an increased incidence of neoplasias, while no difference was observed between conventional (azathioprine+methylprednisolone: Aza+MP) and CsA therapy or in CsA monotherapy vs. double or triple therapy. However, KS occurrence correlated both with CsA dose (RR 15.2 for monotherapy; 12.5 for double therapy; 2.98 for triple therapy) and with 10 or more i.v. methylprednisolone pulses for treatment of rejection (RR 5.2). We conclude that in our series CsA does not increase the risk for development of neoplasias, when compared to conventional immunosuppression.

Adolescent↗
PubMed1996

[Role of surgery in the treatment of acute hemorrhagic non-variceal lesions in the upper gastrointestinal tract].

From January 1993 to December 1994, out of 244 cases of upper gastrointestinal hemorrhage observed 25 patients underwent surgical treatment. Twenty-nine bleeding varices were excluded from this study. Early endoscopy revealed the source of bleeding almost in all cases (84%). All patients received, at the time of admission, medical treatment associated in 7 cases (28%) to endoscopic injection therapy. Emergency surgery indications were massive bleeding persistent bleeding, rebleeding and macroscopic findings of lesions. The aim of this report is to verify the respective roles of medical, endoscopic and surgical therapies in relation to the nature of the bleeding lesion and the entity of the hemorrhage. Results with regard to indication, clinical data, surgical technique were compared with literature data.

Adult↗
PubMed1996

[Diagnostic role of mammography and clinical examination in the framework of a screening program for breast carcinoma in Brescia].

Screening by mammography is at present the only way to obtain good results in terms of diagnosis of breast cancer at an early stage. In this paper we present the results of first and second rounds of a mammographic and clinical screening programme carried out in the health district of Brescia. At the first round out of 129 cancers detected, mammography was diagnostic in 124 cases; in 82 cases, the examination also allowed the identification of a suspicious nodule, while in 42 cases non palpable neoplasm was diagnosed with mammography alone. In the remaining 5 cases mammography was negative and only clinical examination led to the discovery of breast neoplasms. In the second round, in the 125 cancers detected, mammography was diagnostic in 124 cases; clinical examination allowed the identification of 59 of these tumours, while in 65 cases non palpable tumours were found with mammography alone. Only in one case mammography was negative and clinical examination led to the identification of the tumour.

Breast Neoplasms↗
PubMed1996

[Impact of a screening program on the surgical treatment of breast carcinoma].

Results are presented concerning the first two cycles of a breast cancer screening program carried out by USSL 41 (the local social health center). 38,000 women were examined in a period ranging from 1987 to 1993 and more than 250 early stage tumors were diagnosed. Early detection by screening is confirmed by tumor size and nodal involvement. Overall, this program carried out in Brescia met requirements set by international and national scientific committees. Good results were obtained as far as quality standards are concerned. The importance of screening is evaluated concerning surgical treatment undergone by the patients. The study of surgical treatment clearly shows the gradual progression of conservative surgery deviating from more destructive operations.

Age Factors↗
PubMed1996

[Intestinal anastomosis with biodegradable ring].

The authors report their experience using biofragmentable anastomosis ring (BAR) in bowel anastomosis. Starting January 1993 to February 1994, 46 intestinal anastomoses were performed using BAR, and particularly 39 end-to-end colo-colostomies, 2 end-to-side colo-colostomies and 5 end-to-side ileo-colostomies. 35 patients were affected by colonic neoplasm, 5 patients by diverticular colonic complications- and 5 patients by several unusual bowel diseases. Four emergency operations were performed, while 42 patients had an accurate bowel preparation before surgery. In this series of patients one case of preoperative mortality is reported, due to massive pulmonary embolism. Instead several minor complications occurred in other patients, such as paroxysmal atrial fibrillation (one case), basal pleuritis (one case), hyperpyrexia (three cases), temporary subocclusion or delayed canalization (five cases). Only one patient suffered from intestinal occlusion induced by adhesions and a second laparotomy was required. Delayed canalization seems to be caused by the small size of the BAR employed (25 mm) or by inadequate intestinal preparation, that usually occurs in emergency operations. After surgery all patients were followed up and 18 of them were examined by coloscopy six months after surgery. No clinical problem connected with bowel anastomosis was reported and all anastomosis looked quite previous and resilient. No anastomotic stenosis was found. In our experience and from recent reviewed reports, BAR seems to be a rapid, effective and safe device for sutureless bowel anastomosis.

Adult↗
PubMed1996

[Geographic distribution of digestive system tumor mortality in Italy, 1970-87].

The geographical distribution of mortality rates from tumours of digestive tract in Italy is analyzed in this paper. The analysis is based on official mortality data collected by the National Institute of Statistics (ISTAT). Age-adjusted mortality rates for stomach cancer presented the highest values in some provinces of the North and the Center, and the lowest values in the South of Italy. A same geographical pattern was observed for men and women, and during the whole considered period. Colorectal cancer presented the highest rates in the North-West of the country, and in some provinces of Liguria and Tuscany. The lowes rates were observed in the South, particularly in Calabria and Sicily. Mortality for this cancer was positively associated with degree of urbanization. The geographical pattern remained fairly constant in time, but the North-South differences narrowed during the years 1980s. A similar geographical distribution, characterized by the highest mortality levels in the north-eastern regions of Italy, was observed for cancers of the oral cavity and pharynx, of the oesophagus, of the pancreas, and for male tumours of the liver. Female liver cancer presented, on the contrary, the highest mortality levels in the southern regions.

Cluster Analysis↗
PubMed1995

In vivo evaluation of timing, degree, and distribution of bacterial translocation following experimental small bowel transplantation.

These studies were designed to evaluate the correlation between morphologic and functional changes after heterotopic auxiliary small bowel isograft with systemic venous drainage and two ostomies in 20 Lewis rats. Morphologic damage of the graft was scored by full-thickness biopsies before surgery and 1, 3, 5, and 7 days after transplant. Functional evaluation of the graft was done, at the same time points, by urinary excretion of lactulose and mannitol injected in the proximal ostomy. The intestinal permeability was also studied by injecting Escherichia coli labeled with indium-111 oxine in the proximal ostomy. Translocation of radiolabeled bacteria was quantitated in extraintestinal tissues by radionuclide counts and number of viable organisms and in vivo by scintigraphic imaging. One day after transplant, significant graft damage (score 17.2 +/- 4.2) was observed when compared with the pretransplant value (7.3 +/- 2.6). The degree of tissue injury was similar on days 3 (15.8 +/- 3.5) and 5 (16.1 +/- 3.9) after transplant and remained high on day 7 (11.8 +/- 2.8). The lactulose to mannitol ratio showed a significantly increased permeability on day 1 (17.5) versus pretransplant values (2.6), remained high on day 3 (8.6), and returned to normal values on day 5 (2.8). Translocation of bacteria to distant organs, as measured by both radionuclide counts and number of viable organisms, was strikingly enhanced on day 1 after transplantation, compared with control animals, but returned to the pretransplant value on day 3. A good qualitative and quantitative correlation was observed between radionuclide counts in the extraintestinal organs and in vivo images obtained by scintigraphic scanning. In conclusion, in this model, timing and degree of bacterial translocation do not seem to correlate well, with the exception of the acute post-transplantation phase, with morphologic and permeability changes of the graft. Evaluation of translocation by scintigraphic imaging appears a suitable approach to study in vivo the kinetics and distribution of this process.

Animals↗
PubMed1995

Comparison between pylorus-preserving and Whipple pancreatoduodenectomy.

Between 1989 and 1993, 62 patients underwent Whipple pancreatoduodenectomy and 75 pylorus-preserving pancreatoduodenectomy (PPPD); 35 patients in the first group and 37 in the second had pancreatic adenocarcinoma while 17 and 21 patients respectively had periampullary adenocarcinoma. The aim of this retrospective study was the comparison of operative outcome, nutritional recovery and survival of patients who underwent these two operations. No significant differences were found between the two groups in operative mortality or morbidity, duration of gastric aspiration and time to start of solid meals. Patients who underwent PPPD had a better nutritional recovery: the increase of both body-weight and serum albumin level at 6 months after discharge was significantly higher for those who had preservation of the whole stomach (P < 0.001 and P < 0.05 respectively). No significant difference in survival was found between the two procedures when patients with pancreatic or periampullary adenocarcinoma were analysed separately.

Adult↗
PubMed1995

Evaluation of recombinant human erythropoietin to facilitate autologous blood donation before surgery in anaemic patients with cancer of the gastrointestinal tract.

The aim of this study was to determine whether the preoperative administration of recombinant human erythropoietin (rHuEPO) could increase the rate of autologous blood donation and reduce the perioperative need for homologous blood in anaemic patients with cancer. Twenty-two anaemic (haematocrit less than 34 per cent), iron-deficient (iron less than 700 micrograms/l) patients, with gastric or colorectal cancer scheduled for elective surgery, were allocated randomly to two groups. The first (n = 11) received iron saccharate 200 mg/day intravenously for 12 consecutive days. The second (n = 11) received rHuEPO subcutaneously (300 units/kg as first administration, and 100 units/kg 4, 8 and 12 days later) with supplemental iron. On days 4, 8 and 12, if the haematocrit was greater than 34 per cent, patients donated one unit (350 ml) of autologous blood. In the iron group the mean haematocrit did not change from admission (31 per cent) to day 12 of treatment (31 per cent), and no patient could donate autologous blood. In the rHuEPO group, eight patients donated two units of autologous blood and three donated one unit. Four patients in the iron group received perioperative transfusion of homologous blood compared with none in the rHuEPO group. Administration of rHuEPO facilitated the donation of autologous blood and reduced perioperative homologous blood transfusion in anaemic patients with cancer.

Adolescent↗
PubMed1995

Portal hypertension and iron depletion in patients with genetic hemochromatosis.

Clinically, portal hypertension has been considered to be less common and less severe in patients with cirrhosis resulting from iron overload in homozygotes for genetic hemochromatosis than in patients with cirrhosis of other causes. To characterize the prevalence and progression of portal hypertension in genetic hemochromatosis (GH), 120 cirrhosis and iron-overloaded patients were compared with a control group of 120 patients with postnecrotic cirrhosis (PNC) who were matched for gender, age, Child's class, and alcohol abuse. Gastroesophageal endoscopy and abdominal ultrasonography were performed at diagnosis and repeated every 12 months and every 6 months, respectively, to evaluate the presence and severity of varices, the caliber of the portal vein and its collaterals, and splenic size. At diagnosis a similar frequency of varices was observed in patients with GH (25%) and in PNC (24%), as well as of portal vein abnormalities and spleen enlargement. During the follow-up period, all but two of the patients with GH were treated by phlebotomy and depleted of excess iron. After a mean of 6 +/- 4.3 (SD) years of observations (range, 2 to 10 years), varices were improved or completely reversed in 26% of patients with cirrhosis and GH but in only 5% of those with PNC (P < .01). Bleeding from varices was observed in only one patient with GH but in five patients with PNC. Of 22 patients with GH in whom portal hypertension was unmodified or worsened, 16 had coexistent hepatic viral infection.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Experimental peripheral neuropathy induced in adult rats by repeated intraperitoneal administration of taxol.

Taxol, a natural extract with antineoplastic properties, is known to be neurotoxic in humans. Its neurotoxicity after systemic administration, however, has never been studied in detail at the morphological level in humans and in animals. In this study we administered taxol intraperitoneally to female Wistar rats and we performed an extended neurophysiological and morphological examination of the peripheral nerves, dorsal root ganglia, spinal rootlets, and spinal cord. The results obtained in this experimental model indicate that taxol induces pathological changes mainly in the peripheral nerves, but they are present also in the ventral and dorsal spinal rootlets and spinal dorsal column fibers. The dorsal root ganglia and spinal cord neurons were, on the contrary, unaffected. The most impressive change induced by systemic taxol administration was intraaxonal neurotubule accumulation. Schwann cells showed signs of "activation" but clear demyelination was not observed. We conclude that with the use of this model it is possible to induce a peripheral neuropathy in the Wistar rat which resembles that reported in humans and which can, therefore, be used to better understand the basic mechanism(s) of taxol toxicity and to evaluate protective strategies in an attempt to reduce it.

Animals↗