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Biomedical subjects

A Costa

Publications and source records attributed to A Costa.

At least 343 records · Page 19Linked to original sources
PubMed1989

The quality control of tuberculin PPD products from seven Latin American laboratories.

The Pan American Health Organization, through its Pan American Zoonoses Center (CEPANZO), distributes the concentrated stock solution of PPD batch RT23 (1 mg ml-1 = 50,000 TU ml-1) to national central laboratories. In the laboratories the stock solution is diluted to 2 TU/0.1 ml and dispensed with the addition of Tween 80 and either chinosol or phenol as preservatives in rubber-stoppered vials for use in the Mantoux test. The expiry date is usually fixed at six months after filling. Samples of nine lots of PPD 2 TU from seven countries (Argentina, Brazil, Colombia, Dominican Republic, Ecuador, Paraguay and Uruguay) were received by CEPANZO for quality control. The biological activity and phenol concentrations of these samples were assayed periodically after storage at 4, 25 or 37 degrees C either unopened or opened and re-used in a manner simulating extreme field conditions of use and storage. The object of the study was to determine the stability of the biological activity as well as the maintenance of sterility of these conditions with a view to assessing the need for stricter requirements for the labelling of tuberculin. The results obtained showed that PPD 2 TU with 0.4-0.5% (w/v) phenol added, and dispensed in vials, was stable in its biological activity and maintained its sterility. Therefore, it seems unnecessary to issue stricter requirements than those currently applied.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Tolerability of the synthetic retinoid Fenretinide (HPR).

Fenretinide, N-(4-hydroxyphenyl)retinamide (HPR), is a synthetic retinoid which has been proven effective in inducing cell differentiation and in inhibiting carcinogen induced mammary tumors in rodents. Because of its efficacy and low toxicity in animals, HPR has been proposed for chemopreventive evaluation in humans. Thus, a randomized trial has been conducted to select a dose which can be administered over a lengthy period of time and with acceptable toxicity. The retinoid was administered orally to patients already operated on for breast cancer in daily doses of 100, 200 and 300 mg for 6 months and subsequently at 200 mg for another 6 months. No acute toxicity was found. Dermatological toxicity was minimal and no liver function abnormalities were observed. Nausea and headaches were infrequent and always mild. Menstrual irregularities were recorded with similar frequency in the treatment and placebo groups and appeared to be more age related than drug dependent. After 6 months of treatment one of 25 patients taking 300 mg HPR daily experienced impaired night vision, confirmed by the electroretinogram, and resolved by interruption of treatment. Because the 300 mg daily dose is possibly associated with impaired dark adaptation, the recommended dose for chemoprevention trials of HPR is 200 mg per day.

Adult↗
PubMed1989

Antioxidant enzymatic activities and resistance to oxidative stress in primary and subcultured rat astroglial cells.

The survival of neural tissues depends in part on the balance between the formation of free radicals due to oxidative metabolism and the transformation of the free radicals to non-toxic compounds. Serial subculture of rat glial cells as described here resulted in a decrease of the specific activities of several antioxidant enzymes and a glial specific marker for astrocytes. Thus, there was an increased susceptibility to oxidative stress in cultures by the third passage. These subcultured glial cell cultures may represent a useful model for the study of free radical induced neural damage that may be relevant to CNS trauma and aging.

Animals↗
PubMed1989

Chest X-ray survey in the follow-up of breast cancer patients.

The authors report on 182 cases of intrathoracic metastases (ITM = lung, pleura or mediastinum) observed as first single recurrences in the course of the follow-up of patients treated for primary breast cancer. ITM were detected on standard two-views chest X-ray (CXR) at regular follow-up visits and in absence of subjective symptoms (102 A cases) or in the interval between two consecutive planned controls because of the onset of subjective symptoms (80 S cases). The average disease-free interval since primary treatment was significantly shorter in A with respect to S cases (40.3 vs. 28.5 months, P less than 0.001) as a consequence of the early detection achieved by CXR survey. On the contrary, prognosis was not influenced by ITM early diagnosis as the 10-year survival since primary treatment did not differ significantly between A or S cases (12% vs. 10%, P = 0.68). Results were confirmed on multivariate (Cox's) analysis, adjusting for potential confounders such as age or nodal status. Periodic CXR survey looks a very questionable policy as it does not seem to have any favourable impact on prognosis. Its routine use in breast cancer patients should thus be carefully reconsidered.

Adult↗
PubMed1989

Serum procollagen-III-peptide level correlates with disease activity in myelofibrosis with myeloid metaplasia.

In 78 patients with myelofibrosis with myeloid metaplasia (MMM) the serum procollagen III peptide activity (s-PIIIP) had a higher mean value than in 22 normal adult volunteers (22.5 v. 10 ng/ml). Nevertheless, 21.8% of the patients had s-PIIIP within the 95th percentile of the normal control group (16 ng/ml): with respect to those whose concentrations exceeded this limit, patients with normal s-PIIIP levels were younger (55.8 v. 61.2 years), had a higher Hb value (12.3 v. 10.5 g/l), a lower serum ferritin level (106 v. 464 micrograms/l) and a higher platelet count (390 v. 216 x 10(9)/l). In the overall patient population, s-PIIIP was significantly higher in those with symptoms of active disease (fever, sweating, weight loss) than in subjects with non-active disease (28 v. 16.9 ng/ml). At univariate analysis s-PIIIP correlated (at the 5% level) with increasing WBC, serum ferritin and number of transfusions and with decreasing Hb and platelet count. At multivariate analysis increasing WBC, serum ferritin and age proved to be independently associated with s-PIIIP. No relationship was found between the s-PIIIP level and morphometric grading of bone marrow fibrosis, megakaryocyte number, or lymphoid infiltration. Longitudinal studies showed that s-PIIIP increased with disease progression. The conclusion of the study is that s-PIIIP correlates more with overall disease activity than with the extent of bone marrow fibrosis.

Adult↗
PubMed1989

Myelofibrosis with myeloid metaplasia following essential thrombocythaemia.

We report a male patient in whom a diagnosis of essential thrombocythaemia was made at the age of 25. The clinical course was characterised by recurrent thrombotic episodes during the first few years of the disease, followed by a relatively benign course. He was treated with 32P, nitrogen mustard and plateletpheresis. A transformation into myelofibrosis with myeloid metaplasia was revealed 20 years after ET diagnosis. The length of the disease and the 32P therapy are discussed as factors favouring this metamorphosis.

Humans↗
PubMed1989

Endocrine, hematological and immunological changes in surgical patients undergoing general anesthesia.

Some hematological endocrine, and immunological reactions in surgical patients under general anesthesia were studied. While serum cortisol, fT4, T4, rT3 levels increased, TBG, TSH, fT3 and T3 decreased. Cortisol increase and T3 and fT3 decrease were still significant three days after surgery. TSH and T3 decrease was significantly related to cortisol increase. CD4 (helper-inducer) cells dropped, rosettes, CD 5, CD 8, CD 16 (NK) and T HLA-DR (activated) number of cells did not change significantly. The decrease in CD 4 subset was significantly related to cortisol increase. Thus surgery was followed by a reduced thyroid function and decreased CD 4 subset. However this was observed also in the few patients in whom the serum cortisol level did not change. These reactions may represent immunosuppression occurring in the postoperative period.

Adult↗
PubMed1989

[Energy expenditure at rest and body composition in obese subjects before and after weight loss].

In 7 obese subjects (3 males and 4 females), before (T0) and after (T60) weight loss, and in 10 nonobese subjects (4 males and 6 females) as controls, resting energy expenditure (REE) and body composition were evaluated. In obese subjects fat-free mass (FFM) and fat mass (FM) were significantly reduced after weight loss. REE, expressed in absolute value, was significantly higher in obese subjects at T0 with respect to controls (1683 +/- 77.3 vs. 1425 +/- 70.5 Kcal/day; p less than 0.05); in obese group REE was significantly lower at T60 (1563 +/- 63.5 Kcal/day) than at T0 (p less than 0.01). The decrease in REE observed in the obese group after weight loss was related only to the loss of FFM (r = 0.88; p less than 0.01). REE, expressed in relation to FFM, was not different between control and obese subjects at T0 (28.64 +/- 0.42 vs 26.40 +/- 1.08 Kcal/Kg-FFM/day; pns); however, this value was significantly lower in the obese group at T60 (25.99 +/- 1.07 Kcal/Kg-FFM/day) with respect to controls (p less than 0.05). It is concluded that a reduction in REE, due at least in part to the loss of FFM, may contribute to the difficulty in the maintenance of body weight often observed in obese subjects after a period on hypocaloric diet.

Adult↗
PubMed1989

Ultrastructural findings of Candida albicans blastoconidia submitted to the action of fenticonazole.

A study has been conducted about ultrastructural changes induced by an imidazole derivative, fenticonazole (Lomexin), on Candida albicans blastoconidia. The structural upset has been progressively exerted starting from coating membrane surfaces throughout cytosol components and nuclear compart, so that the existence can be assumed for a direct dependence of these changes upon activity failure by a few organules. Membrane permeability processes have resulted to be involved, which are the main metabolic paths in the defective ATP synthesis, and enzyme blockades responsible for peroxide accumulation.

Antifungal Agents↗
PubMed1988

Liposoluble vitamins and lipid parameters in breast cancer. A joint study in northern Italy and southern France.

The relationship between breast cancer, liposoluble vitamins, cholesterol and triglycerides was investigated by means of a hospital-based case-control study conducted at Milan (Italy) and Montpellier (France). These parameters were measured in blood samples taken from 319 cases and 344 controls. The interview included an evaluation of dietary intake of liposoluble vitamins. No difference emerged in liposoluble vitamin consumption, whereas a statistically significantly higher serum level of cholesterol and plasma level of vitamin E existed in cases compared to controls. The difference in plasma vitamin E was confirmed after adjustment for total cholesterol and triglycerides. In contrast, vitamin A variations appear to follow triglyceride trends. A multivariate analysis of the vitamin E plasma level was performed after classification of cases and controls according to quintile distribution of controls. All known risk factors plus age, serum total cholesterol and triglycerides were used as covariates. The odds ratio value for the highest quintile of plasma vitamin E is: 4.2 (1.9-9.0).

Adult↗
PubMed1988

Psychologic aspects of patients participating in a phase I study with the synthetic retinoid 4-hydroxyphenyl retinamide.

One hundred and one patients participating in a phase I study with the synthetic retinoid 4-HPR (4-hydroxyphenyl retinamide) were evaluated. The study was set up by Veronesi et al. during 1986 at the National Cancer Institute of Milan. The patients were randomized into 4 groups of therapy: 25 in the placebo group, 25 in the group receiving a daily dose of 100 mg of HPR, 26 in the group receiving 200 mg/day of HPR, and 25 in the group receiving 300 mg/day of HPR. All patients were previously treated at our Institute for breast cancer. None had received adjuvant therapy, chemotherapy or hormone therapy. After 4-5 months from the beginning of treatment, all patients received a series of tests to evaluate anxiety, depression and sexual life. Moreover, during one the follow-up checkups after 4-5 months, the patients filled-out a self-scoring mood questionnaire. The results did not show any particular differences between the groups, although we found that the administered drug and experimental setting do not interfere with the psychologic state of the participating patients.

Adaptation, Psychological↗
PubMed1988

The relationship of dietary intake and serum levels of retinol and beta-carotene with breast cancer. Results of a case-control study.

The possible association between the risk of breast cancer, blood level, and dietary intake of preformed Vitamin A (retinol) and beta-carotene was investigated in a case-control study carried out from May 1982 to June 1985. The patients studied were 214 previously untreated individuals with T1-2, N0-1, M0 breast cancer admitted to the National Cancer Institute of Milan and 215 controls admitted for conditions other than neoplastic or metabolic disorders. Both cases and controls were selected from an age group ranging from 30 to 65 years old. Plasma levels of retinol and beta-carotene were tested from blood samples drawn during the first day after admission to the hospital. A questionnaire about diet was used to estimate the mean intake of 69 food items from which a daily dietary index of retinol and beta-carotene intake was computed. Information relating to the woman's history, socioeconomic status, and known risk factors for breast cancer was also collected. No association was found between beta-carotene (in the diet or blood) or dietary retinol and the risk of breast cancer. As for blood retinol, our data show a significant trend of increasing risk with higher levels; multivariate relative risk for subsequent serum levels based on the control quintiles, are 1, 1.5, 1.8, 1.7; (test for linear trend: chi-square = 8.26). Thus, these findings, together with the results of other studies, suggest that retinol and beta-carotene are unlikely to be related to the risk of breast cancer.

Adult↗
PubMed1988

Effect of epidermal growth factor and insulin on DNA, RNA, and cytoskeletal protein labeling in primary rat astroglial cell cultures.

The effect of epidermal growth factor (EGF) and insulin on DNA, RNA, and cytoskeletal protein labeling in primary rat astroglial cell cultures was investigated. Cultures were grown for 15-30 days in vitro in 10% fetal calf serum (FCS)-supplemented medium and then maintained in serum-free basal medium (DMEM) supplemented with fatty acid-free bovine serum albumin (BSA) for a starvation period of 24 hr before the addition of factors. The effect of factors was tested at different times (4, 10, 22, and 28 hr). At each time, [methyl-3H]thymidine or [5,6-3H]uridine was added to the control and treated cells; the incubation time after the addition of labeled precursors was 2 hr at 37 degrees C. The results obtained indicated that the addition of EGF or FCS significantly stimulated [methyl-3H]thymidine incorporation into DNA, reaching the maximum effect after 22 hr. EGF alone significantly stimulated [3H]uridine incorporation into RNA, and this effect was already maximum at 4 hr and remained constant up to 22 hr. The addition of insulin alone caused a slight increase in nucleic acid labeling for short times (4-10 hr). In contrast with EGF, no detectable stimulation of incorporation of labeled precursors after insulin treatment for 22 hr was observed. On the other hand, the addition of insulin in the presence of EGF induced an increase of the values observed with EGF alone on macromolecular synthesis at all the times studied. Furthermore, a decrease in cell number was observed in confluent cultures maintained for 1 week in medium containing DMEM + BSA in comparison to serum-supplemented (DMEM + BSA + FCS) cultures.

Animals↗
PubMed1988

Adrenocorticotropic hormone and catecholamines in maternal, umbilical and neonatal plasma in relation to vaginal delivery.

The aim of this study was to evaluate the effect of vaginal delivery on both ACTH and catecholamines (DA, NE, E) secretion in the mother, the fetus (umbilical artery) and the newborn. Blood samples were obtained from 19 normal pregnant women and the corresponding umbilical cords, and from the newborns. Seventeen normal nonpregnant women, matched for age and parity, were also included in the study as "nonpregnant controls". The results demonstrate that in the mother, plasma catecholamines (CA) concentrations during labor and delivery are elevated above the values reported for normal nonpregnant women and there is a predominant E response. The concentrations of CA in umbilical arteries are very high compared to those in the corresponding mother and they fall rapidly after birth. Unlike that in the mother, the predominant CA response to parturition in the fetus and newborn infant is NE. The extraction rate of DA, NE and E from placenta is approximately 60%. The peripheral plasma levels of ACTH in pregnant women during labor are twice and 10 times as high as those observed in the corresponding umbilical arteries and in nonpregnant women respectively. At delivery they increase further. No significant differences are found between the values measured in the arterial cord blood and those in the venous cord blood and in the newborns. A way of explaining the prevalence of E and the higher ACTH/E ratio found in the mother in comparison with the fetus could be that in the mother the stress response to parturition is regulated mainly by the pituitary-adrenal axis, whereas in the fetus there is a prevalent stimulation of the sympathetic nervous system.

Adrenocorticotropic Hormone↗
PubMed1988

A prognostic classification of myelofibrosis with myeloid metaplasia.

The dependence of survival time on a set of prognostic factors was explored by means of Cox's regression model in 137 cases of myelofibrosis with myeloid metaplasia (MMM). The following parameters recorded at diagnosis proved to be important independent indicators of a poor prognosis: a higher value for age, a lower value for Hb concentration, a higher value for immature myeloid cells in peripheral blood (IMC), a lower value for total erythroid iron turnover (TEIT), and a bone marrow red cell aplasia (RCA). A prognostic classification tree was constructed whose terminal nodes (risk groups), described by simple logical conditions upon important indicators, were characterized by significantly different expected survival. The two extreme risk groups lend themselves to a simple, but complete description. The low-risk group (19.7% of the sample) comprises cases who had the diagnosis of MMM before age 45 and a number of IMC constantly lower than 24%. The actuarial proportion of patients surviving at 15 years was 100%. The high-risk group (29.9% of cases) comprises patients with age greater than 45 and Hb lower than 13 g/dl, associated with RCA, or with a relatively decreased erythropoiesis (TEIT lower than 2 times the normal) or with IMC greater than 24%. Seven out of the 11 who died within this group developed blastic crisis. Median survival time of the group was 69 months.

Adolescent↗
PubMed1988

Comparative analysis of different approaches to investigate cell kinetics.

The potential of different methods to investigate proliferative activity of cell populations was analysed for non-Hodgkin's lymphomas. Cells in S phase and all cycling cells were determined on cell suspensions obtained from fresh lymph node material by [3H]-thymidine autoradiography [( 3H]TdR LI), a monoclonal antibody to bromodeoxyuridine (BrdU LI), and the monoclonal antibody Ki67. A good correlation was observed between the values of [3H]TdR LI and BrdU LI (rs = 0.90; P less than 0.01), [3H]TdR LI and S phase (rs = 0.62; P less than 0.01) and [3H]TdR LI and Ki67 (rs = 0.64; P less than 0.01) in individual lymphomas. Using the median values obtained from the different approaches as cut-off points to define slowly and rapidly proliferating tumours, the best agreement was observed between [3H]TdR LI and BrdU LI (91%) and poorer agreements, even though statistically significant, were observed between [3H]TdR LI and S phase (73%) or Ki67 (76%). In conclusion, the kinetic information derived from different approaches was more or less concordant and newly proposed approaches should be directly and carefully verified for their prognostic relevance before using them as alternatives to conventional methods.

Adolescent↗