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Biomedical subjects

M E Valencia

Publications and source records attributed to M E Valencia.

At least 55 records · Page 3Linked to original sources
PubMed1994

[Serum activity of the lactate dehydrogenase enzyme in patients with human immunodeficiency virus infection].

FOUNDATION: Many patients with infection by the HIV show an increase in the levels of the lactodehydrogenase (LCH) enzyme. In most of these cases, such increase has been associated to the presence of pneumonia by Pneumocystis carinii. In order to analyze other possible causes of this increase, we conducted a study in which the clinical, analytical and immunological condition of a group of HIV+ patients with increased levels of LDH was compared to another group whose values were within normal limits. MATERIAL AND METHODS: The clinical records of 200 patients with HIV infection were retrospectively reviewed. The patients were divided into two groups depending if their LDH values were greater than (group A) or lower than (group B) the upper limit considered as normal in our laboratory (230-460 UI/L). Group A included 150 patients and Group B, 50. RESULTS: Both groups were similar with respect to age, sex risk group for HIV infection, hemoglobin level, platelet count and renal function. The number of patients fulfilling AIDS criteria was significantly greater (p < 0.05) among those with LDH above 460 UI/L. Leukocytes and lymphocytes CD4+ values were significantly greater (p < 0.05) among group B. The diseases more frequently diagnosed in group A were: tuberculosis in 41 cases (27%), pneumonia by P. carinii in 31 (21%), bacterial pneumonia in 19 (13%), disseminated disease by cytomegalovirus in 14 (9%) and by Mycobacterium avium in 12 (8%). Among the patients with increased LDH, their levels were similar in the patients with tuberculosis, pneumocystosis and in the patients with AIDS and those which were in the first stages of the HIV infection. CONCLUSION: The increase in LDH among the patients with HIV infection in the era of the prophylaxis against P. carinii must be carefully interpreted. Greater levels of this enzyme are little specific, but have a high sensitivity in the case of tuberculosis and pneumocystosis.

Adult↗
PubMed1994

[Study of 164 episodes of infectious endocarditis in drug addicts: comparison of HIV positive and negative patients].

OBJECTIVE: Intravenous drug-addicts (IVDA) are the most important risk group for acquiring HIV and developing infective endocarditis (IE) in Spain. The clinical and evolutive features of a large series of IE in HIV-infected IVDA are reported and compared with those observed in a smaller group of patients without HIV infection. METHODS: A retrospective analysis was made of 164 episodes of IE from 136 patients diagnosed in a Service of Infectious Diseases in Madrid (1986-1992). IE was defined according to the modified Von Reyn criteria and only the probable and definite IE episodes were evaluated. RESULTS: A total of 143 IE episodes occurred in 117 IVDA infected with HIV (group A) and 21 episodes in 19 HIV-negative patients (group B). Most of seropositive patients were asymptomatic carriers of HIV (54%) and only 22% had AIDS. The IE onset was acute for 97% patients in group A and 81% in group B, with fever and respiratory symptoms as main complaints. Chest X-ray was normal in 19% of cases in group A and in 28% in group B. Septic embolisms were observed in 56% and 41% of patients in group A and B, respectively. The vegetation originated mainly on the tricuspid valve and Staphylococcus aureus was recovered from most blood-cultures. The mortality rate was similar in both groups, 6% and 5% in groups A and B, respectively. CONCLUSIONS: Most IVDA with IE were HIV-positive patients in this series. IE is usually reported in the early stages of HIV infection and apparently its presence has no influence on the clinical course of IE.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Basal metabolic rate and body fatness of adult men in northern Mexico.

To investigate the possibility that overprediction of basal metabolic rate (BMR) of tropical populations is related to differences in fatness between tropical and temperate populations, 32 Mexican men aged 18-40 years underwent measurements of BMR and body fat content. The men were divided into four body mass index (BMI) groups (< 20, 20-25, 25-30 and 30-40). The mean weight was 78 (range 52-119) kg and the mean height was 1.75 (range 1.61-1.89) m. BMR was measured in the subjects after an overnight stay in a residential unit by a Deltatrac ventilated hood indirect calorimetry system. Body fat content was determined by 2H2O dilution. The relationship between BMR and body weight was analysed by linear regression and the equations derived were compared to the values predicted using the FAO/WHO/UNU (1985) equations. The FAO/WHO/UNU equations overestimated measured BMR by 9.8%, 9.6%, 7.8% and 5.5% in the four groups. The overall difference was 8.2%, which was statistically significant (P < 0.001). The intercepts of the two equations were significantly different (P < 0.001) by 532 kJ/day, but there was no significant difference between the slopes of the two regression equations. There was no significant difference between BMR/kg fat-free mass in the four BMI groups. The results therefore do not support the possibility that the overprediction of BMR in tropical populations by international prediction equations based on body weight is accounted for by differences in fatness between tropical and temperate populations.

Adipose Tissue↗
PubMed1993

[Neoplasms associated with human immunodeficiency virus infection. Study of the clinical course of 70 patients].

BACKGROUND: A different epidemiologic pattern of the neoplasms associated to the human immunodeficiency virus (HIV) has been described in the Mediterranean area. The aim of the present study was to analyze the epidemiologic, clinical and evolutive characteristics of these patients. METHODS: A retrospective study of 74 neoplasms in 70 patients (15% of AIDS cases) was carried out. The following variables were analyzed: risk group, state of the infection (HIV), stage and type of tumor, immunohematologic data, opportunistic infections (OI), response to treatment, evolution and prognostic factors. RESULTS: Thirty-four Kaposi's sarcomas (SK) were diagnosed, 32 non Hodgkin's lymphomas (NHL), 4 Hodgkin's disease (HD), 2 seminomas, 1 cutaneous carcinoma and one undifferentiated tumor. Sixty-eight patients were males with a mean age of 32 years. The risk group was: homosexual (52%), drug abuse (24%), hemophilia (14%), and heterosexual contact (10%). The neoplasm was the first manifestation of HIV infection in 60% of the patients. Sixteen patients with SK were treated with chemotherapy (CMT), radiotherapy (RT) or interferon and stabilization of the disease was achieved in 50% of the cases. Twenty-six patients with NHL received treatment: 26 with CMT, 9 with RT and 4 with surgery. Complete remission was achieved in 27% and partial in 61% of the cases. Overall mortality was 56% and median survival 13 months. Most of the patients died due to progression of the tumor or infection. The prognostic factors associated to shortened survival were: advanced stage of AIDS, OI at the time of diagnosis of the tumor and a decrease in hemoglobin, total lymphocytes and CD4. CONCLUSIONS: The lower incidence of neoplasms among patients with acquired immunodeficiency disease and the differences in the distribution of the histologic types may be related with the demographic features of the risk groups in Spain. Survival is determined more by opportunistic infections than by the tumor itself.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Effect of diet composition on protein requirements of children and adults in northern Mexico.

The overall vegetable and animal protein combinations of the diet in Northern Mexico were determined through a dietary population survey. Vegetable sources made up 45% and animal protein was 55% (45V/55A). Further combinations of up to 100% vegetable protein dietary mixtures (100V) were studied to test the sensibility of the variations on protein requirements of pre-school, school children and adults. Diets were analyzed for amino acid composition and in vivo protein digestibility in rats to estimate true protein requirements according to FAO/WHO/UNU (1985). The effect on the pre-school group showed the widest variation with 1.46 g/kg/day in the 45V/55A to 2.63 in the 100V. For the school-aged children and adults the variations were 1.15-1.79 and 0.94-0.84 g/kg/day respectively.

Adolescent↗
PubMed1993

Utilization of crude and refined palm and palm kernel oils in broiler diets.

Four experiments were conducted to evaluate the use of crude and refined palm (PAO) and palm kernel oil (PKO) in diets for broiler chickens. In Experiment 1, refined PAO and PKO were compared with corn oil (CO) and poultry oil (PO) at levels up to 10%. In Experiment 2, refined PAO and PKO were compared with PO at levels up to 8%. In Experiments 3 and 4, crude PAO and PKO were compared with PO at levels up to 8%. Diets were formulated based on the energy level assigned to PAO; other oils were added in amounts calculated to be isocaloric with an inert filler as required. Live production variables were measured. Samples of birds were processed to determine carcass characteristics, and fatty acid composition of adipose tissue was determined. In all studies, broilers fed crude or refined sources of PAO and PKO grew as well and utilized their feed as efficiently as those fed diets with isocaloric amounts of CO or PO. There were minimal interactions of source and dietary level of oil in any of the studies. Dressing percentage and quantity of abdominal fat were not influenced by source of supplemental oil; however, the fatty acid profile of adipose tissue was altered by the source of supplemental oil. There were only minor differences in fatty acid content of adipose tissue of broilers fed PAO (either crude or refined) versus those fed PO. However, increasing levels of PKO resulted in increased deposition of saturated fatty acids, especially lauric and myristic acid, and decreased concentrations of both monoenoic and polyunsaturated fatty acids. The resulting change in hardness of adipose tissue may prove to be advantageous in marketing.

Adipose Tissue↗
PubMed1993

[Development of a feeding formula from a protein concentrate of chick-pea (Cicer arietinum)].

A medical formula was developed from a chick-pea (Cicer arietinum) protein concentrate obtained by ultrafiltration (67.8% of protein). Additionally sucrose, methionine, milk flavor, and mixtures of corn and coconut oils, vitamins and minerals were used, to perform FAO/WHO standards. All ingredients were blended in water to 50 degrees C, and the mixture was spray-dried with a Spray-drier using inlet and outlet air temperatures of 170 and 90 degrees C respectively. The nutritive value of the formula was evaluated with the Net Protein Ratio (NPR), Nitrogen Utilization (NU) and both relatives values to casein ANRC (R-NPR and R-NU). The proximal analysis of the infant formula was: protein 16.0% (with 4.9 g/16 g N of reactive lysine), fat 25.8%, moisture 4.0%, ash 3.2% and carbohydrates 51.0%. The values of NPR, R-NPR, NU and R-NU were 3.95, 83.6, 3.55 and 82.5 respectively. This results shown the chick-pea protein concentrate, potencially utilizable as an ingredient in the formulas for medical purposes.

Dietary Proteins↗
PubMed1993

Spontaneous pneumothorax in patients with the human immunodeficiency virus: study of eight cases.

OBJECTIVE: To evaluate the risk factors and the natural history of spontaneous pneumothorax in patients with human immunodeficiency virus infection (HIV). METHODS: We studied eight HIV infected patients with spontaneous pneumothorax. Variables assessed included sex, age, risk factor for HIV infection, use of Pneumocystis carinii pneumonia prophylaxis, total and CD4 positive lymphocyte count, previous history of Pneumocystis carinii pneumonia or pulmonary tuberculosis, chest X-ray film, presence of simultaneous opportunistic infection, partial pressure of oxygen in arterial blood gas determination and clinical outcome. RESULTS: The patients were predominantly male and intravenous drug abusers. Mean age was 28 years (range: 21-44). Five patients had acquired immunodeficiency syndrome, 2 oral candidiasis and one asymptomatic HIV infection. Three had previously had Pneumocystis carinii pneumonia and six a concurrent opportunistic infection. No one was receiving aerosolized pentamidine prophylaxis. The pneumothorax was bilateral in two cases. Chest tube evacuation was required in seven, and six patients died. Only two patients without opportunistic infection were discharged. CONCLUSIONS: We conclude that spontaneous pneumothorax is a serious problem with high mortality in patients with advanced human immunodeficiency virus infection. Previous or active Pneumocystis carinii pneumonia appear to be a risk factor for developing pneumothorax. It seems to be independent of aerosolized pentamidine use.

AIDS-Related Opportunistic Infections↗
PubMed1992

The effect of environmental temperature and humidity on 24 h energy expenditure in men.

The effects of environmental temperature and humidity and their interaction on 24 h energy expenditure were measured using whole-body indirect calorimetry in eight normal-weight young men who wore standardized light clothing and followed a controlled activity regimen. A randomized-block experimental design was used, with temperature effects assessed by measurements at 20, 23, 26 and 30 degrees, while humidity was altered from ambient (50-65% relative humidity) to high (80-93% relative humidity) at 20 and 30 degrees only. There was no significant effect of humidity on 24 h energy expenditure at the two extreme temperatures in this range, though when periods of sleep and exercise were excluded the energy expenditure at high humidity was significantly higher than that ambient humidity (P < 0.02). The effect of temperature at ambient humidity levels showed lower values at 23 and 26 degrees than at 20 and 30 degrees (P < 0.02). The effect of temperature was not equally apparent in all components of the 24 h energy expenditure, as sleeping metabolic rate and the energy cost of walking and cycling showed no significant effect of temperature over this range. This raises the possibility that the effects of temperature are attributable to behavioural changes during the waking portion of the day rather than any non-shivering thermogenic mechanisms at tissue level.

Adult↗
PubMed1992

Serum erythropoietin levels in anaemic patients with advanced human immunodeficiency virus infection.

This study attempts to evaluate the adequacy of the erythropoietin (EPO) response in 42 anaemic patients with advanced human immunodeficiency virus (HIV) infection [30 with acquired immunodeficiency syndrome (AIDS) and 12 with AIDS-related conditions] by comparing their serum EPO levels with those found in a non-HIV reference population consisting of 36 patients with anaemia of chronic disorders (ACD) and 57 with iron deficiency anaemia (IDA). Although the average Hb concentration was similar in the three groups, the EPO level for HIV patients (mean +/- SEM, 64.3 +/- 7.7 mU/ml) did not differ significantly from that in ACD patients (45.3 +/- 8.3 mU/ml, P > 0.1), and both groups had a lower mean EPO level (P < 0.05 and P < 0.01 respectively) than IDA subjects (133.5 +/- 18.7 mU/ml). Thirteen HIV patients on zidovudine therapy showed similar mean Hb and EPO levels to those in the untreated patients. A significant inverse correlation between the log of serum EPO and the Hb values was observed in the three groups. However, this relationship was found to be stronger in IDA patients than in either HIV or ACD subjects (P < 0.001), with no difference between the two latter groups (P > 0.2). These data suggest that the EPO response is blunted in the anaemia associated with advanced HIV infection.

Acquired Immunodeficiency Syndrome↗
PubMed1992

[Nutritional quality of a protein concentrate of chick-peas (Cicer arietinum) obtained by ultrafiltration].

The nutritive quality of a protein concentrate from chickpea (Cicer arietinum) obtained by ultrafiltration was evaluated. Three biological assays and the apparent protein digestibility (APD) were utilized. In addition, the effect of the supplementation with methionine to protein concentrate was observed. The protein efficiency ratio (PER), net protein ratio (NPR) and nitrogen utilization (NU) were 1.86, 3.11 and 3.11 respectively, compared with the values of casein ANRC of 2.50 4.02 y 4.01. Only the PER of the protein concentrate from chick-pea (Cicer arietinum) was increased significantly (< 0.05) higher with respect to raw chick-pea (Cicer arietinum), but lower with respect to casein ANRC.

Animals↗
PubMed1991

[Angiothrombotic pulmonary granulomatosis in intravenous drug addicts].

Two cases of angio-thrombotic lung granulomatosis in intravenous drug addicts are described. This entity has been previously described in drug addicts who inject oral drugs intravenously. Talc, which is used in the preparation of several drugs, cotton and other substances provoke at lung vessels level, thrombotic phenomena with strange body granuloma formations. Depending on the predominating localization of these lesions, interstitial pneumonia or pulmonary hypertension can later occur, such is the case in one of our patients who had a fatal evolution in a short period of time.

Adult↗
PubMed1991

[Obtention of a protein concentrate of chickpea (Cicer arietinum) by ultrafiltration].

A protein concentrate was obtained from chick-pea (Cicer arietinum) flour aqueous extract. The factor involved in the recovery of protein were the flour: water ratio, and the pH. The best aqueous extract was subjected to infiltration in a Romicon HF1/2SSS unit equipped with hollow fiber membranes cartridges with a nominal molecular-weight cut-off point of 50,000 daltons. The concentrate was spray-dried and the product obtained had the following composition, expressed in g/100 g: 67.8 protein with 4.9 g/16 g N of reactive lysine; 17.3 fat, 10.0 carbohydrates, and 4.9 ash (dry basis). The nitrogen solubility index was 93 and the color, by Hunter, was L = 86.8.

Edible Grain↗