PubMed Health⌕ Search

Biomedical subjects

V Salazar

Publications and source records attributed to V Salazar.

17 recordsLinked to original sources
PubMed2007

Effect of exogenous administration of melatonin and growth hormone on pro-antioxidant functions of the liver in aging male rats.

Aging is accompanied by changes in the morphology and physiology of organs and tissues, such as the liver. This process might be due to the accumulation of oxidative damage induced by reactive oxygen (ROS) and reactive nitrogen species (RNS). Hepatocytes are very rich in mitochondria and have a high respiratory rate, so they are exposed to large amounts of ROS and permanent oxidative stress. Twenty-four male Wistar rats of 22 months of age were divided into three groups. One group remained untreated and acted as the control group. The second was treated with growth hormone (GH) (2 mg/kg/d sc) and the third was submitted to treatment wit 1 mg/kg/d of melatonin in the drinking water. A group of 2-months-old male rats was used as young controls. After 10 wk of treatment the rats were killed by decapitation, and the liver was dissected and homogenized. Mitochondrial, cytosolic and microsomal fractions were obtained and cytochrome C, glutathione peroxidase, s-transferase and nitric oxide (NO) were measured. Aging induced a significant increase in mitochondrial nitric oxide. An increase in cytochrome C in the cytosolic fraction and a reduction in the mitochondrial fraction with age was also observed. Both GH and melatonin treatments significantly reduced the enhanced measures and increased the reduced values. A reduction in glutathione peroxidase and glutathione S-transferase was found in old control rats when compared with the group of young animals. Treatment for 2.5 months of old rats with GH and melatonin were able to increase the enzymes reaching values similar to those found in young animals. In conclusion, GH and melatonin treatment seems to have beneficial effects against age-induced damage in the liver.

Aging↗
PubMed2006

Obesity, voracity, and short stature: the impact of glutamate on the regulation of appetite.

BACKGROUND: World-wide obesity has risen to alarming levels. We present experimental support for a new and very challenging hypothesis linking obesity, voracity, and growth hormone (GH) deficiency, to the consumption of elevated amounts of the amino-acid glutamate (GLU). Supraphysiological doses of GLU are toxic for neuronal cells. METHODS: Human data were obtained from 807,592 German conscripts born between 1974 and 1978, and from 1,432,368 women of the German birth statistics (deutsche Perinatalerhebung) 1995-1997. The effects of orally administered monosodium glutamate (MSG) were investigated in 30 pregnant Wistar rats and their offspring. Pregnant animals either received no extra MSG, or 2.5 g MSG, or 5 g MSG per day, up to the end of the weaning period. In all, 2.5 g, respectively 5 g, MSG accounted for some 10%, respectively 20%, of dry weight of the average daily food ration. After weaning, MSG feeding was continued in the offspring. FINDINGS: Morbid obesity associates with short stature. Average stature of conscripts progressively declines when body mass index increases above 38 kg/m2. Also morbidly obese young women are shorter than average though to a lesser extent than conscripts. Oral administration of MSG to pregnant rats affects birth weight of the offspring. Maternal feeding with 5 g MSG per day results in severe birth weight reduction (P<0.01). Weight increments remain subnormal when MSG feeding to the mothers is maintained during weaning (P < 0.01). GH serum levels are affected in animals that received MSG during prenatal life via maternal feeding. Animals that are kept on high MSG diet (5 g MSG per day) continue to show serum GH levels that are as low or even lower than those of MSG injected animals (P < 0.05), both at day 30 and at day 90 of life. Animals that were kept on medium MSG diet (2.5 g MSG per day) showed low serum GH levels at day 30 of life (P < 0.01), but seemed to partially recover before day 90. Almost identical results were observed in IGF-1 serum levels. Oral MSG resulted in dose dependent voracity. The animals fed 5 g MSG per day increased water uptake by threefold (P < 0.01), and food uptake by almost two-fold (P < 0.01). The influence of MSG is in general more marked in males than in females. INTERPRETATION: GLU is a widely used nutritional substance that potentially exhibits significant neuronal toxicity. Voracity, and impaired GH secretion are the two major characteristics of parenterally administered GLU-induced neuronal damage. GLU maintains its toxicity in animals even when administered orally. Males appear to be more sensitive than females. The present study for the first time demonstrates, that a widely used nutritional monosubstance--the flavouring agent MSG--at concentrations that only slightly surpass those found in everyday human food, exhibits significant potential for damaging the hypothalamic regulation of appetite, and thereby determines the propensity of world-wide obesity. We suggest to reconsider the recommended daily allowances of amino acids and nutritional protein, and to abstain from the popular protein-rich diets, and particularly from adding the flavouring agents MSG.

Adult↗
PubMed2005

Effect of isoflavone administration on age-related hepatocyte changes in old ovariectomized femal Wistar rats.

Aging seems to be due to the accumulation of oxidative damage in cells and molecules. On the other hand, menopause and ovariectomy induce deleterious effects on different organs and systems that have been shown to be counteracted by estrogens and in a not so evident form also with phytoestrogens. The present study has investigated whether the administration of a commercial soy extract that contains approximately 10% isoflavones was able to modify some parameters related to oxidative stress and inflammation in hepatocytes isolated from old ovariectomized female Wistar rats. Eighteen 22-month-old animals that had been previously ovariectomized at 12 months of age were divided into four groups: ovariectomized control rats, estradiol-treated ovariectomized females and ovariectomized rats treated with isoflavones. Six intact female rats of 2 months of age were used as reference group. Hepatocytes were isolated and cultured, and carbon monoxide (CO) and nitric oxide (NO) release, as well as adenosyl triphosphate (ATP), cyclic guanosyl monophosphate (cGMP), phosphatidylcholine (PC) and lipid peroxide (LPO) content of cells were evaluated. Uterus was also removed and weighed. Hepatocytes isolated from old ovariectomized rats showed a decrease in ATP content as compared to young animals. Age also induced an increase in LPO cell content. NO, CO and cGMP were augmented with age, and PC synthesis showed a dramatic reduction. Treatment with either estradiol or isoflavones were able to improve all the mentioned parameters altered in hepatocytes isolated from old ovariectomized rats, and the magnitude of the improvement was similar for both treatments. Ovariectomy induced a significant reduction in uterine weight, which was significantly counteracted by estradiol treatment but not by isoflavone administration. In conclusion, the administration of a soy extract containing isoflavones seems to prevent oxidative changes in hepatocytes isolated from old ovariectomized female rats, without modifying uterus weight.

Aging↗
PubMed2005

Purification of a myotoxin from the toadfish Thalassophryne maculosa (Günter) venom.

Venom was milked by gently pressing the base of the opercular and dorsal fin spines. Three fractions were obtained by molecular exclusion high pressure liquid chromatography (HPLC) (Protein Pak 125SW, Millipore Corporation) column, but only the last one with 22.7 min retention time (rt) was biological active (TmPP-22.7). This fraction was rechromatographed on reversed phase HPLC chlorobutylsilane columns (C4, Vydac) nine fractions were obtained, but only one (TmC4-47.2) with 47.2 min rt was biologically active. MALD-TOF mass analysis was carried out on two samples of TmC-47.2 and the results were 15,161.36 and 15,154.70 a.m.u., respectively. Raw venom (1040 microg/ml) depolarised frog (Hyla crepitans) muscle irreversibly from -85 (-88, -81) mV (n=20, median and its 95% CI) to -18 (-24, -15) mV (n=24). The biological activity in TmPP-22.7 (38 microg/ml), which depolarised muscle fibres from -79 (-82, -76) mV (n=20) to -63 (-69 -57) mV (n=24). The depolarising fraction was TmC4-47.2 (50 microg/ml) which depolarised muscles from -87 (91, -82) mV (n=33) to -63 (-76 -51) mV (n=53); the depolarising effect at this concentration was completely reversed on washing with normal saline for 2 h. Muscles treated with 1 microM tetrodotoxin (TTX) were depolarised from -80 (-85, -72) mV (n=49) to -44 (-56, -31) mV (n=44) when 100 microg/ml TmC4-47.2 were applied with TTX; washing 130 min with 1 microM TTX repolarised to -59 (-69, -50) mV (n=25). We also present evidence that TmC4-47.2 induces myonecrosis in mice.

Amino Acid Sequence↗
PubMed2004

Histopathological changes and inflammatory response induced by Tityus discrepans scorpion venom in rams.

Anesthetized rams envenomed s.c. with 40 microg/kg Tityus discrepans scorpion venom developed fasciculation, hypothermia, polyuria, pulmonary wet rales, tachypnea, respiratory distress and arrhythmia. Rams developed a cascade of inflammation reactions, characterized by activation of macrophages, fibroblasts and neutrophils, neutrophil infiltration and aggregation, vasculitis, arteritis and abundant fibrin deposition. At the inoculation site, venom was detected by immunohistochemistry in the extra cellular matrix, lymphatic vessels' and venules' lumen, inside macrophages and surrounding nerves. Extra cellular matrix was degraded at the inoculation site perhaps by activated neutrophils. Envenoming produced hepatocytes with Mallory body-like vacuoles which may be due to the increased plasmatic levels of TNF-alpha and IL6. Venom produced degranulation and vacuolization of acinary cells as well as interstitial swelling and necrosis. Necrosis of the Langerhan's islets occurred occasionally. Lungs showed the most deleterious effects developing wall collapse and necrosis, diffuse injury of the alveolar capillary barrier, interstitial and alveolar fibrin deposits with strong neutrophil infiltration. Massive infiltration of lymphocytes and macrophage occurred in the intestinal submucose, to the point that it modified villi and intestinal folding morphology. Envenomation developed a marked leukocyte aggregation surrounding nerves at the inoculation site. This study reveals that beyond its neurotoxicity, Tityus venom produces a severe and widespread inflammatory syndrome, expressed as histopathological changes at the site of inoculation, as well as in remote organs such as pancreas, lungs, intestine and liver. Our results suggest that not all remote targets are directly affected by the venom but that, as proposed earlier, are modified by inflammation by products produced elsewhere.

Animals↗
PubMed2004

Modelling Tityus scorpion venom and antivenom pharmacokinetics. Evidence of active immunoglobulin G's F(ab')2 extrusion mechanism from blood to tissues.

Modelling Tityus scorpion venom and antivenom pharmacokinetics. Evidence of active immunoglobulin G's F(ab')(2) extrusion mechanism from blood to tissues. We measured pharmacokinetic parameters for T. discrepans venom in rams. Forty, 75 or 100 microg/kg venom were injected subcutaneously in the inner side of the thigh. Plasma venom content (venenemia) was determined by enzyme-linked immunosorbent assay (ELISA) from 0 to 300 min after injecting venom. Venenemia was fit to a three-compartment model (inoculation site, plasma and extra vascular extracellular space), it was assumed that the venom may also be irreversibly removed from plasma. Calculated time course of venom content shows that at any time no more that 30% of the venom is present in plasma. Venenemia peaks at 1h and decays afterwards. Fluorescently labelled antivenom [horse anti-TityusF(ab')(2) or fraction antigen binding, immuglobulin without Fc chain covalently bound to fluorescine or fluorescamine] pharmacokinetics was determined. Although F(ab')(2) molecular weight is >/=10 times bigger that toxin's, the rate of outflow of F(ab')(2) from blood to tissues was approximately 4 times faster than the venom's outflow. Venom content in the injection site decays exponentially for >6h, this prediction was confirmed immunohistochemically. Only approximately 5% of the venom is eliminated in 10h; approximately 80% of the venom is in the tissues after 2h and remains there for >10h.

Animals↗
PubMed1991

[Insulinoma and pregnancy. Clinical case].

A 25 year old woman developed severe episodes of hypoglycemia during the first weeks of pregnancy. Insulin blood levels of 53 uU/ml and Peptide C levels of 6.5 ng/dl were shown associated to a blood glucose level of 34 mg/dl. Echotomographic examination of the abdomen was unrewarding. Surgical exploration revealed a 1.5 cm tumor located at the junction of the body and tail of the pancreas, which was removed. Hypoglycemia disappeared and pregnancy continued uneventfully ending in a normal delivery at 40 weeks. The newborn was normal and no motor or psychologic abnormalities have been noted during follow up to 2 years of age.

Adult↗
PubMed1991

[Pulmonary function in the preterm and full-term newborn during the neonatal period: II. Pulmonary function].

The pulmonary function of 18 preterm neonates weighing less than 1500 g. and of 35 full-term newborn infants weighing more than 2500 g. at birth was measured during the neonatal period. The children were grouped according to their postnatal age (less than 24 h, 24 h- 7 days, and greater than 7 days). The inspiratory and expiratory flow was measured by means of a pneumotachograph and the esophageal pressure by means of a feeding tube filled with distilled water. Lung compliance (CL) was significantly lower in the preterm infants than in full-term infants for all postnatal age groups. However, with relation to body weight (CL/Kg) there were no significant differences. The expiratory lung resistance was higher than the inspiratory resistance in all groups. The work of breathing (Wr) was significantly lower in the preterm neonates than in term infants in all postnatal age groups. Nevertheless, as Wr refers to body weight, there were no significant differences.

Birth Weight↗
PubMed1989

[Pulmonary function in newborn infants with transitory tachypnea and pneumothorax].

The pulmonary function has been studied in 13 newborns with transient tachypnea (TT), matched for birth weight in 7 newborns with pneumothorax (NT) with higher birth weight than 2,500 g and the results were compared with 21 newborns healthy, matched for weight. The study was done in first 24 h after birth. Inspiratory and expiratory flow was measured by a pneumotachograph, esophageal pressure though a water-filled feeding tube. Lung compliance was lower in the newborns with respiratory distress, which results in less tidal volume, whereas the minute ventilation remains unchanged due higher significantly breathing rate. Lung resistance were higher in the newborns with Nt, although without significantly differences. Work of breathing was higher in the newborns with respiratory distress although without significantly differences.

Humans↗
PubMed1981

[Threshold for bicarbonate in epileptic children in treatment with anticonvulsant drugs (author's transl)].

The study comprised 31 ambulatory epileptic children aged 1,5-14 years (mean: 7.37), receiving treatment with anticonvulsant drugs. Authors found that renal threshold for bicarbonate was inferior when compared to control group (mean = 21.3 mEq/l., SD = 1.75; mean = 25.34 mEq/l., SD = 1.29; p less than 0.0001), low calcemia (mean = 9.12 mg./dl., SD = 0.51; mean = 9.43, SD = 0.45; p less than 0.01) and elevated alkaline phosphatase (mean = 212.6 mU/ml., SD = 75.9; mean = 127.4, SD = 50.2; p less than 0.01). No significant difference in urinary excretion of cyclic AMP, phosphate or calcium was observed. Nineteen patients who had subnormal threshold (inferior to -2 SD in the control group) when compared with control group, had: low calcemia (p less than 0.01), high alkaline phosphatase (p less than 0.0001) and a similar urinary cyclic AMP, calciuria and phosphaturia. A negative correlation between renal threshold to bicarbonate and serum phosphate (r = -0.49, p less than 0.01) and a negative correlation between the urinary cyclic AMP and the duration of treatment (r = -0.42, p less than 0.05) was found. It is commented that although in deficiency rickets, proximal tubular acidosis is due to secondary hyperparathyroidism, in their patients despite they had biochemical characteristics of rickets, low calcemia and elevated alkaline phosphatase, the descent of renal threshold to bicarbonate is a nonparathoromone mediated phenomenon.

Acidosis, Renal Tubular↗
PubMed1980

[Assessment of chemotactic activity in newborn infants and during the first year of life (author's transl)].

Chemotactic activity in 58 full term newborn and in infants during the first year of life was studied. Samples were taken from cord blood and blood drawn at three and 15 days after birth and at one, three, six and 12 month of age. Chemotactic activity was assessed by Boyden's technique. It was found that samples obtained before the first month of life had a decrease of function as compared with those of the mothers. Chemotactic indexes were parallel to those of mothers by the end of the first year of life. These findings suggest that impairment of the function observed in infants may be due to a deficit in synthesis of complement factors.

Adult↗
PubMed1980

[Serum opsonic activity in newborns and through the first year of life (author's transl)].

Serum opsonic capacity for "Staph. aureus" was studied in 58 full term infants at birth and through their 1st year of life. The comparison between serum opsonic activity from the infants and their mothers disclosed that infants had a significant decrease of the opsonic activity during the first three months of life. The study of serum levels of C3, C4, IgG and IgM, showed a significant correlation between opsonizationa and low levels of the complement components C3 and C4.

Age Factors↗
PubMed1978

[Infantile brucellosis (author's transl)].

Some aspects concerning brucellosis are revised. This is a disease with a high incidental rate among the children's population in Salamanca and bordering provinces. The local prevailing epidemiologic conditions are reviewed, as well as the most outstanding clinical features, which are in children, according to the author's personal experience, less protean than in adult's illness.

Adolescent↗
PubMedDate not supplied

[Descriptive epidemiology of ambulatory neurological care in the Vega Baja (Alicante) area].

AIMS: The aim of our work is to analyse ambulatory neurological care in the area of Vega Baja, which is located in the province of Alicante (Spain), in order to find out: a) the demographic characteristics of the population that visits the neurologist; b) the motives that led to the visit; c) the diagnoses carried out. PATIENTS AND METHODS: A prospective two year study of patients over the age of 14 sent to the Neurology department. The reasons for the visit were classified into 15 categories and the diagnoses were given a code according to the criteria set out in the International Classification of Diseases 9th edition. RESULTS: A total of 2,227 patients were included in the study. The annual incidence of first visits was 10.6 per 1,000 people. 60% of the patients were women. The average age was 51.6 years old. Headache was the most frequent reason for the visiting the doctor. One out of every three patients visited because of headache and/or facial pain. The five most frequent diagnoses in the under 65 group were, in descending order of frequency: migraine, tension type headache, epilepsy, syncope and anxiety. The five most common diagnoses in the over 65 group were, in descending order of frequency: Alzheimer, Parkinson, transitory cerebral ischemia, cerebral thrombosis and epilepsy. CONCLUSIONS: The type of ambulatory neurological pathology depends on the age of the patients, and thus we find that headache is prevalent in the younger patients whereas neurodegenerative and vascular pathological conditions are more common in those over the age of 65.

Adolescent↗
PubMedDate not supplied

Action of 2'-deoxycoformycin on mitogen-induced lymphoproliferation in the neonatal period.

The effect of 2'deoxycoformycin (dCF), a potent inhibitor of adenosine deaminase (ADA), on the proliferation of mononuclear cells from cord blood and from healthy controls as a response to the two mitogenic agents PHA and ConA was studied. The addition of dCF simultaneously with the mitogen did not modify cell proliferation either in neonates or in controls. Added 20 min before the mitogens, dCF induced in adults lymphocytes a significant inhibition in the response to PHA (68.11 +/- 10.40% of response in control cultures) and to ConA (58.78 +/- 26.23%). By contrast, in the neonatal period it induced a stimulatory effect on this response, both when PHA (117.64 +/- 26.48% of basal response) and ConA (108.18 +/- 21.72%) were employed. The possibility is discussed that this different function in lymphocyte behaviour in the newborn might contribute to the immunologic abnormality which children affected with ADA deficiency may exhibit at this age and also to the delay in the onset of clinical manifestations of immunodeficiency due to the defect in this enzyme.

Adenosine Deaminase Inhibitors↗
PubMedDate not supplied

Action of ketotifen on different functions of neutrophil polymorphonuclear cells.

The results concerning the action of Ketotifen "in vitro" on the adherence, spontaneous and chemotactic mobility and phagocytosis of neutrophil polymorphonuclear cells (PMNs) of the non-specific immunological system are presented. PMN cells were incubated for 30 min at 37 degrees C prior to the evaluation of different functions, with the following concentrations of Ketotifen: 1, 10 and 100 ng, and 1 and 10 micrograms/ml., final concentration. PMN cell adherence to glass spheres was unaffected by doses of the drug considered to have pharmacological action; however, a statistically significant enhancement was observed in this function from a concentration of 10 ng./ml. onwards. Mobility, both spontaneous and chemotactic was inhibited in the presence of Ketotifen only at high doses; the chemotactic function was more susceptible to the action of the drug at doses of 10 ng./ml. than spontaneous mobility, which required ten-fold greater concentrations for inhibition to take place. Likewise, the phagocytosis of C. albicans was inhibited by the presence of the drug at doses of 10 ng./ml. and higher. In conclusion, Ketotifen in PMN cells at pharmacological doses only induces a slight increase in adherence and a decrease in the functions of mobility and phagocytosis of C. albicans; at least "in vitro", much higher concentrations, which are not found with the doses usually employed, are required for these functions to be altered significantly.

Cell Adhesion↗