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Biomedical subjects

J Lozano

Publications and source records attributed to J Lozano.

At least 55 records · Page 3Linked to original sources
PubMed1992

Human placental transfer of zinc: normal characteristics and role of ethanol.

The fetal alcohol syndrome is primarily an impairment of growth and development. Zinc deficiency also causes abnormal fetal growth. Moreover, alcohol has been shown in some rodent studies to impair placental transport of zinc. The purpose of this investigation was to define better normal human placental zinc transport and the effects of alcohol on this process. To do this we employed the isolated perfused single cotyledon human term placental model, as well as the cultured human cytotrophoblast. In the perfused placental studies, it was shown that zinc is transferred by the placenta very slowly, about 6% of the rate of transport of antipyrine, a freely diffusible marker. The transfer is comparable in both directions, maternal to fetal and the reverse. Zinc does not cross the placenta against a zinc concentration gradient, in either direction. Rather there is good evidence of significant uptake (storage) of the zinc by the placenta on the recirculating compartment side of gradient studies. Moreover, when the perfusion fluid was low (0.2 g/100 ml) in albumin, about twice as much zinc accumulated in the perfused cotyledon and there was less zinc in the maternal compartment, as compared to perfusion with ten-fold higher (2.0 g/100 ml) albumin concentrations. Thus, ligand binding in the perfusate importantly influences placental zinc uptake. Interestingly, however, the increased placental binding of zinc did not translate into greater transfer of zinc to the fetal compartment. Thus, normal zinc transfer is slow, equal bidirectionally, and dependent on ligand binding in perfusate and placenta.(ABSTRACT TRUNCATED AT 250 WORDS)

Culture Techniques↗
PubMed1991

Psychiatric disorders among poor victims following a major disaster: Armero, Colombia.

We evaluated 102 adult victims of low socioeconomic status living in tent camps 8 months following the Armero disaster in Colombia to ascertain the level of psychiatric morbidity. Ninety-one percent of the subjects identified by the screening instrument as being emotionally distressed met DSM-III criteria for a psychiatric disorder. The most frequent diagnoses were posttraumatic stress disorder and major depression. These findings indicate that a simple screening instrument can be reliably used for the detection of significant emotional problems among disaster victims. They also show that these victims are not merely distressed; rather, they present clear and treatable psychiatric disorders that center on anxiety and depression. Interventions for their adequate management need to be designed, implemented, and evaluated. In a developing country, however, the high prevalence of mental disorders among disaster victims far exceeds the specialized mental health resources. The general health sector, particularly the primary level of care, must participate actively in the delivery of mental health services to meet this need, particularly for a socioeconomically disadvantaged population. The narrow range of psychiatric disorders detected among the disaster victims makes it possible to circumscribe the training of the primary care worker in disaster mental health to these priority conditions.

Adult↗
PubMed1991

Alterations of ATP levels and of energy parameters in the blood of alcoholic and nonalcoholic patients with liver damage.

Blood adenine nucleotides were determined in patients with alcoholic and non-alcoholic liver diseases. They included patients with alcoholic hepatitis (AH), alcoholic liver cirrhosis (ALC), non-alcoholic liver cirrhosis (NALC), and amoebic liver abscess (ALA) (28 patients). A decrease of 28% to 39% in blood ATP levels was observed among the patients with AH and the cirrhotic groups, respectively (p less than 0.05), whereas no significant changes in blood ATP levels were detected in the ALA group. Although total blood adenine nucleotides were significantly diminished in AH, ALC, and NALC groups, the AH patients retained their energy relationships within normal range. On the other hand, the cirrhotic groups, independently of their etiology, failed to maintain an adequate ATP/ADP ratio, energy charge, and phosphorylation potential in the blood, suggesting a decreased energy availability in their blood cells. Nevertheless, the mechanism involved in these effects remains to be elucidated, a failure of the damaged liver to supply purines to extra-hepatic tissues might be a major event altering the blood energy parameters.

Adenosine Triphosphate↗
PubMed1990

Determination of portal insulin absorption from peritoneum via novel nonisotopic method.

The absorption mechanism of insulin administered in the peritoneal cavity (IP) is of current interest because of the near availability of implantable insulin-infusion devices for the treatment of diabetes. To determine the fraction of insulin absorbed by the portal circulation after IP administration, a novel nonisotopic method is described. Conscious fasting diabetic dogs were studied at normoglycemia via the euglycemic insulin-clamp method. Posthepatic appearance of insulin and C-peptide were measured in peripheral blood during IP or intravenous (IV) equimolar infusion of insulin and C-peptide at two sequential 3-h infusion rates of 3.2 and 12.8 pmol.kg-1.min-1. Prior studies have shown that 40-60% of portal insulin is extracted at first pass by the liver, whereas C-peptide is not extracted. Thus, the fraction (F) of IP insulin not taken up by liver at first pass and consequently the fraction absorbed by the portal circulation can be derived from insulin (I) and C-peptide (C) plasma concentration values at steady state with a monocompartmental model where F = (IIP/IIV)(CIV/CIP). The mean +/- SE value of F was 49.7 +/- 8.8%. Glucose disappearance rates were lower with IP than IV infusion but similar when peripheral insulin levels were matched. We conclude that IP insulin is almost entirely absorbed by the portal circulation and induces lower glucose disappearance rates than IV insulin because of lower peripheral circulating insulin levels. Whether these properties make the IP route a more appropriate route for insulin therapy than the subcutaneous or IV routes remains to be established.

Absorption↗
PubMed1989

Comparison of intraperitoneal and subcutaneous insulin administration on lipids, apolipoproteins, fuel metabolites, and hormones in type I diabetes mellitus.

The relative biologic efficacy of intraperitoneal (IP) insulin administration over peripheral routes of insulin infusion for artificial delivery devices is still poorly documented. Thus, the effects of IP insulin administration have been compared with the effects of subcutaneous (SC) insulin administration upon circulating fuel metabolites, hormones and lipoproteins. In a longitudinal study, seven type I diabetic patients, aged 33 +/- 3 years, duration 16 +/- 4 years, were studied. SC intensive insulin therapy was used for 3 months, then insulin was infused IP via an implantable pump for 6 months with a similar good blood glucose control. Lipids including high density lipoprotein (HDL) cholesterol and low density lipoprotein (LDL) cholesterol, apolipoproteins A-I, A-II, and B were measured every 3 months. Although all values remained in the normal range, significant changes occurred in plasma triglycerides (63 +/- 9 SC v 88 +/- 12 mg/dL IP, P less than .05) and HDL-cholesterol (57 +/- 4 SC v 42 +/- 4 mg/dL IP, P less than .05) without concomitant changes in apolipoprotein levels. In another cross-sectional study, six of the patients consumed a standardized 400 kcal breakfast after 0.15 U/kg insulin. Eight SC insulin infused age-, glucose control- and weight-matched diabetic patients also underwent the same test using SC insulin. Six normal subjects consumed the same breakfast and served as controls. Plasma glucose, B-hydroxybutyrate, lactate, alanine, free fatty acids, free insulin and glucagon were measured for five hours after the meal. All measured parameters were comparable in both groups except free insulin and lactate.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Disaster severity and emotional disturbance: implications for primary mental health care in developing countries.

Two months following the 1987 earthquakes in Ecuador, 150 patients in the primary health care clinics of the area were screened for emotional problems; 40% of them were emotionally distressed. Risk factors included not being married, reporting poor physical or emotional health, and having ill-defined physical complaints. The findings from this research are discussed in relation to a disaster of much greater intensity, whose victims were studied by the authors, utilizing the same instrument and research design. The comparison between these 2 groups of disaster victims revealed that: 1) the prevalence of emotional distress was smaller among the Ecuador victims, but the frequency of symptoms among the distressed was similar for both groups; 2) the symptom profiles were remarkably similar; and 3) the most frequent symptoms and the strongest predictors of emotional distress were very similar. These findings support a focused training of health care workers on selected emotional problems that are regularly present among victims of different disasters.

Adolescent↗
PubMed1988

[Primary mental health care for the victims of the disaster in Armero, Colombia].

Seven to eight months after the disastrous volcanic mudslide that destroyed the town of Armero, Colombia, 200 victims were screened up by means of the Self-Reporting Questionnaire (SRQ) for emotional disorders identification. In order to assess disorders' specific nature, a 104-victim subsample was interviewed by psychiatrists. The most frequent diagnosis ranged among (a) Post-traumatic stress syndrome, (b) Depressión, and (c) Generalized anxiety disorder. Our findings help us to point out that (1) In a developing country a higher prevalence of well-defined emotional disorders among victims of any first-magnitude disaster is to be detected at such a level it can safely be said a real epidemic is to be tackled with, (2) Basically, the identified symptomatology confines itself to anxiety-depression disorders, (3) SRQ is indeed an apt instrument for disasters victims screening, and (4) Mental health specialized resources proved to be insufficient for an adequate coverage of the needs of the affected communities to be performed. As far as mental health is concerned, if the necessary services are to be offered so that all aspects involved are taken care of, it is imperative that victims be attended to by primary care workers. So far, mental health primary care area is still lacking a systematical research within a disaster situation framework. We understand that our paper may serve as an initial orientation for this care strategy being duly implemented and furthered up.

Adolescent↗
PubMed1987

Screening for the psychological consequences of a major disaster in a developing country: Armero, Colombia.

Seven months following the volcanic eruption that destroyed the small town of Armero, 200 victims were screened for emotional problems with the Self-Reporting Questionnaire, a simple and reliable instrument. Fifty-five percent of the victims were found to be emotionally distressed. Variables associated with the presence of emotional distress included living alone, having lost previous job, feeling not being helped, not knowing date for leaving temporary shelter, being dissatisfied with living arrangements, complaining of non-specific physical symptoms or epigastric pain, and presenting several physical problems. The high prevalence of emotional distress supports the need to deliver mental care to disaster victims in developing countries through the primary level of care. Our findings provide guidelines for early detection of individuals at risk for developing emotional problems.

Adolescent↗
PubMed1986

Production of monoclonal antibodies to metacyclic trypomastigotes of Trypanosoma cruzi.

Monoclonal antibodies were produced and characterized to the metacyclic trypomastigotes stage of Trypanosoma cruzi. All the monoclonal antibodies (GR-12C/5; GR-P2B/5; GR-F2B/1; GR-J2C/6; GR-E6B/3; GR-A5B/5) also recognized antigens of epimastigotes of T. cruzi. These antigens are associated with the plasma membrane, flagellum, and an intracellular structure located by the nucleus. Immunoprecipitation using the monoclonal antibodies GR-J2C/6 and GR-E6B/3 followed by SDS-PAGE analysis has led to the following results: GR-J2C/6 precipitated two molecules with apparent molecular weights of 58 and 60 kD; the antigen recognized by GR-E6B/3 was a molecule with molecular weight of 68 kD. Only two of the monoclonal antibodies (GR-12C/5 and GR-P2B/5) recognized antigens of promastigotes of both Leishmania mexicana and L. infantum, and are associated with the plasma membrane.

Antibodies, Monoclonal↗
PubMed1976

Acute pancreatitis, pancreatic pseudocyst, and Candida peritonitis in recipient of a kidney transplant.

The case of a recipient of a kidney transplant who developed pancreatitis, complicated by pancreatic pseudocyst subsequently infected by Candidi from an infected parenteral alimentation line, is reported. The case was further complicated by rupture of the cyst leading to Candida peritonitis and development of multiple fistulous tracts between the stomach, ileum, and colon. Despite the 50% mortality of acute pancreatitis in patients with transplants and the 50% mortality reported in Candida peritonitis, the patient was successfully treated by cystogastrostomy, peritoneal lavage, and amphotericin B in association with administration of mannitol and reduction of immunosuppression to a minimal level. After eight weeks of total parenteral alimentation, the fistulous tracts spontaneously closed and the patient was discharged with normal renal function.

Acute Disease↗