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S Molina

Publications and source records attributed to S Molina.

At least 19 recordsLinked to original sources
PubMed2002

Effects of maternal deprivation on adrenal and behavioural responses in rats with anterodorsal thalami nuclei lesions.

There is evidence that repeated maternal isolation of neonatal rats may influence both emotional behavior and Hypothalamic-Pituitary Adrenal (HPA) activity. On the other hand the Anterodorsal Thalami Nuclei (ADTN) exerts an inhibitory influence on the hypophyso-adrenal system under basal and stressful conditions. In the present work we investigated whether neonatal maternal deprivation produces long term effects on the ADTN regulation of behavioral patterns (open field test) and on HPA axis activity. Specifically, we sought to determine whether adult female rats with ADTN lesions, previously isolated for 4.5 hours daily during the first 3 weeks of life, react in endocrinologically and behaviourally distinct manner as compared to controls. The examined groups were: non maternally deprived (NMD)/sham lesioned, NMD/lesioned, maternally deprived (MD)/sham lesioned, MD/lesioned with and without the open field test. At 3 months MD/sham lesioned animals showed a marked decrease in ambulation (P < 0.01), and with ADTN lesion, the rearing values were lower (P < 0.01) and grooming higher (P < 0.05) than NMD. This last data would indicate a high emotional index. Regarding the activity of the HPA axis, maternal deprivation induced a significant decrease in plasma ACTH concentration both in sham and lesioned animals (P < 0.001), and plasma Corticosterone (C) increased in sham animals (P < 0.001). This data would indicate a higher sensitivity of the adrenal glands. After the open field test ACTH and C were different between deprived and non-deprived animals depending on the ADTN lesion. Taking into consideration the increase of ACTH levels in sham lesioned MD animals exposed to the test, we could conclude that this new situation was a stressful situation. Finally in the present work, it was very difficult to relate the behavioral parameters with the endocrine data. It is known that depending on the context, corticosteroids may produce opposite effects on emotional behavior via different receptors in the brain.In summary, neonatal maternal deprivation induced alterations of behavioral patterns and affected the ADTN inhibitory influence on ACTH and C secretion.

Adrenal Glands↗
PubMed2001

Methyl 7-hydroxy-1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydropteridine-6-carboxylate-dimethyl sulfoxide (1/1) forms chains containing O-H...O and C-H...O hydrogen bonds and aromatic pi-pi-stacking interactions.

In the title compound, C11H12N4O5-C2H6OS, the molecular components are linked by a short hydrogen bond with dimensions O...O 2.517 (2) A and O-H...O 168 degrees. Paired C-H...O hydrogen bonds [C...O 3.362 (2) and 3.382 (2) A; C-H...O 157 and 140 degrees] generate cyclic centrosymmetric four-component aggregates reinforced by aromatic pi-pi-stacking interactions, and further C-H...O hydrogen bonds [C.O 3.472 (3) and 3.521 (2) A; C-H...O 156 and 157 degrees] link these aggregates into chains.

Crystallography, X-Ray↗
PubMed2000

Phasic heart period reactions to cued threat and nonthreat stimuli in generalized anxiety disorder.

The hallmark of generalized anxiety disorder (GAD) is chronic uncontrollable worry. A preattentive bias toward threat cues and hypervigilance may support this ongoing state of apprehension. A study was conducted to bridge the attentional and physiological underpinnings of GAD by examining phasic heart period (HP) responses to cued threat and nonthreat stimuli. Thirty-three GAD clients and 33 nonanxious control participants engaged in an S1-S2 procedure that employed cued threat and nonthreat word stimuli, during which phasic HP reactions were recorded. As compared with the control group, the GAD group showed (1) smaller cardiac orienting responses and impaired habituation of cardiac orienting to neutral words, (2) HR acceleration in response to threat words, and (3) a conditioned anticipatory HR deceleration to threat words over repeated trials. The cardiac-autonomic underpinnings of GAD appear to rigidly maintain precognitive defensive responses against threat. This portrayal is discussed in the context of an integrative model that depicts diminished global adaptive variability in GAD.

Adult↗
PubMed1998

Ex vivo proliferation of mesothelial cells directly obtained from peritoneal effluent: its relationship with peritoneal antecedents and functional parameters.

The peritoneal membrane requires anatomico-functional integrity to guarantee long-term stability for peritoneal dialysis (PD). Since mesothelial cells (MC) are active cells and the first part of the membrane to contact the dialysate, they are important in maintaining this stability. Mesothelial cells released daily into peritoneal effluent are able to grow in culture. This growth capacity may be related to some of the anatomicofunctional characteristics of each peritoneum. Our aim was to culture mesothelial cells taken from peritoneal effluents drained by 32 PD-stable patients, and relate this growth capacity to individual peritoneal data. Cells were taken from a residual fluid after sedimentation, washed twice with phosphate-buffered saline (PBS), and seeded into 25-cm2 tissue-culture flasks. These flasks were incubated in a humidified 5%-CO2 atmosphere. After MC confluence, cells were detached by trypsinization, passaged into 24-well plates, and finally counted. Cells were identified by morphology and immuno-histochemical characteristics. Cells from 28 out of 32 patients showed an appropriate growth in culture. Mesothelial cell confluence was reached in a mean of 18.2 +/- 8 days. After 7 days of seeding in plate wells, the cell growth showed a significant and progressive increase until day 16. Mesothelial cell growth rate was inversely related to PD duration. Neither peritonitis incidence nor other demographic characteristic were related to MC growth. Creatinine and urea mass transfer coefficients (MTC), but not ultrafiltration (UF) capacity, were significantly related to MC growth rate. In conclusion, the growth in culture of MC taken directly from PD bags is certainly possible. This growth is influenced by some of the intrinsic peritoneal characteristics derived from the peritoneal dialysis process. This tool could be useful in evaluating individual peritoneal conditions and, probably, as a method for peritoneal viability follow-up, although further research is required.

Ascitic Fluid↗
PubMed1997

An investigation of worry content among generally anxious individuals.

The hypothesis of a distinctive content pattern of worry in generalized anxiety disorder (GAD) was investigated with the use of content categorization of GAD versus nonanxious control worries from both clinical and analogue samples. The GAD groups reported significantly more worry topics than the control groups. Some similarity in content patterns emerged across groups, with the most frequent content category for all groups involving family/interpersonal issues. However, a significant difference in the pattern of relative frequencies across groups was found: GAD was characterized by equally high relative frequencies for miscellaneous and work/school worries, whereas control groups had higher relative frequencies for work/school concerns and lower relative frequencies for miscellaneous worries. The miscellaneous worries of GAD individuals were particularly characterized by worry about minor/routine issues. These findings support DSM-IV descriptions of GAD as involving pervasive worry that includes worry about minor things.

Adult↗
PubMed1997

Septal reconstruction in nasal septum surgery with a composite-sandwich technique.

The authors describe a technique to reconstruct the medial and posterior portions of the nasal septum during surgical correction. This technique uses a "composite sandwich" made of two thin strips of Spongostan containing autologous crushed bone and cartilage. Thirty patients have been operated using this technique with satisfying results.

Adolescent↗
PubMed1995

Clinical trial of glucose-oral rehydration solution (ORS), rice dextrin-ORS, and rice flour-ORS for the management of children with acute diarrhea and mild or moderate dehydration.

OBJECTIVE: To assess the effects of glucose (G)-oral rehydration solution (ORS), rice dextrin (RD)-ORS, and rice flour (RF)-ORS on fluid intake, rapidity of rehydration, and stool output of children with acute diarrhea and mild or moderate dehydration. METHODS: The study was a randomized, double-masked clinical trial. One hundred forty-six male infants, ages 3 to 36 months, were randomly assigned to one of three treatment groups. Clinical evaluations and fluid balances were conducted every 2 to 4 hours for 48 hours. Principal outcome variables were ORS consumption, recovery of hydration status, and fecal output. RESULTS: The groups were similar at admission with regard to age, nutritional status, history of the current episode, and clinical status. There were no differences in ORS consumption by treatment group during any period of study. During the first 6-hour period, patients in group RF had less stool output (16 +/- 14 g/kg/body weight) than those in group G (22 +/- 20 g/kg) or RD (21 +/- 19 g/kg; P < .05). After 12 hours of hospitalization, there were no differences by treatment group. Recovery of hydration status, changes in serum sodium and potassium, and duration of diarrhea in the hospital were similar in all three groups. CONCLUSION: There was a 24% to 27% reduction in stool output during the first 6 hours of treatment among children who received RF-ORS compared with those who received G-ORS or RD-ORS, but this effect did not persist after the first 12 hours of therapy. Because this difference was of small magnitude and limited duration, it has minor clinical importance. Thus, we conclude that the three solutions had similar efficacy for children with acute, watery diarrhea and mild or moderate dehydration.

Acute Disease↗
PubMed1993

Presence of different mitogenic activities in the nocturnal peritoneal effluent of patients treated with CAPD.

Peritoneal cells in continuous ambulatory peritoneal dialysis (CAPD) patients are continually being regenerated. We previously reported that nocturnal peritoneal effluent is mitogenic on human and mouse fibroblasts in culture, especially when a comitogen is present. The nature, origin, and role of this mitogenic activity remain undetermined. The data resulting from the addition of different comitogen to dialysate suggest that the peritoneal effluent contains different growth factors with molecular weight greater than 10,000 dalton. Also, the presence of a growth inhibitor is plausible. In conclusion, different growth-promoting and inhibiting activities are present in the peritoneal effluent, suggesting a complex cellular relationship as a result of peritoneal dialysis with unknown consequences.

Animals↗
PubMed1992

Cocaine-induced alterations in prostaglandin production in rabbit aorta.

To determine if alterations in endothelial prostaglandin production occur after long-term cocaine use, 26 New Zealand White rabbits were randomized to a low fat diet with (n = 12) or without (n = 14) daily intravenous cocaine (2 mg/kg body weight). Rabbits were killed at 6 or 12 weeks. Segments of aorta were examined in blinded manner for histologic changes. Additional slices were incubated in oxygenated Krebs buffer and release of 6-keto-prostaglandin F1 alpha, thromboxane B2 and prostaglandin E2 was assayed by radioimmunoassay. Minimal intimal histologic changes were seen in the aorta of three cocaine-treated rabbits. At 12 weeks 6-keto-prostaglandin F1 alpha was increased in the cocaine group (p = 0.063) as compared with levels in the control group. When rabbits killed at 6 and 12 weeks were considered together, increases in thromboxane B2 (p = 0.044) and a trend to increased prostaglandin E2 (p = 0.083) were seen in the cocaine group. The ratio of thromboxane B2 to 6-keto-prostaglandin F1 alpha was increased in the cocaine group compared with that in the control group (p less than 0.02). These data suggest that an increase in prostaglandin production occurs in the vascular endothelium of rabbits ingesting cocaine before gross histologic changes are evident. In addition, thromboxane B2 increases disproportionately with respect to 6-keto-prostaglandin F1 alpha, suggesting that a milieu for thrombosis may exist in users of cocaine.

Animals↗
PubMed1991

Characterisation of the mitogenic-induced capacity of peritoneal effluent on human and mice fibroblasts in culture.

During continuous ambulatory peritoneal dialysis, solutes capable of stimulating fibroblast activity could be transferred into dialysate; their significance and consequences remain to be established. Sixty-three stable non-selected patients on CAPD were included in this study. Peritoneal transport for water and small solutes was assessed. To explore the mitogenic-induced capacity of peritoneal nocturnal effluent, 50 microliters were added to culture plates of mice and human fibroblasts. Peritoneal effluent alone shows a mitogenic potency slightly greater than insulin and clearly less than bovine fetal serum. When coadjuvants are added, mitogenicity increases but in a variable manner among patients. No differences can be observed in relation to diabetes mellitus, time on CAPD, previous peritonitis, and losses of diffusion capacity. We noted significant inverse linear correlations between mitogenicity value and ultrafiltration, effluent calcium, and creatinine. Neither adrenergic nor calcium-channel blockers influenced these values. We conclude that the peritoneal effluent of CAPD patients has a variable effect on fibroblast growth. Some of the blood components seem to be implicated in this activity. Reduced peritoneal ultrafiltration capacity, probably by a concentration mechanism, is related to a greater mitogenic potency in peritoneal effluent. CAPD patients with impaired ultrafiltration may be at high risk for autoactivation of peritoneal fibroblasts, mainly in mesothelial denudate states.

Adult↗
PubMed1991

Effects of the addition to dialysate of calcitriol H-R-erythropoietin (EPO) and interferon-alpha-2b (IFN) on mitogenic activity of peritoneal effluent.

The presence of cellular growth factors in peritoneal effluents from CAPD patients have been described. The purpose of this paper has been to evaluate the effects of mitogenic activity of peritoneal effluents of the in vivo and in vitro additions of Calcitriol, EPO and IFN. These drugs were added to nocturnal peritoneal dialysate (in vivo) and to nocturnal effluent (in vitro) and then these fluids were tested for mitogenic-induced capacity on mice and human fibroblasts in culture. Our data show that the addition of Calcitriol and Erythropoietin have little effects on peritoneal effluent behaviour. Interferon alpha-2b seem to be useful for decreasing human fibroblasts growth.

Animals↗
PubMed1990

Weanling diarrhea: a case report.

This case report describes a 14-month-old Guatemalan boy suffering from diarrhea and malnutrition. He had been healthy and experienced normal growth until weaning, which began at six months of age. Introduction of semisolid foods at this time was accompanied by bouts of diarrhea and a reduced growth rate. After admission to hospital at 14 months of age, he was found to have protein-energy malnutrition of the edematous type (kwashiorkor) and to be infected with Giardia lamblia. Therapy with metronidazole and a high-protein diet resulted in satisfactory weight gain and cessation of the diarrhea.

Animals↗