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R García

Publications and source records attributed to R García.

At least 145 records · Page 8Linked to original sources

Nasal inflammatory responses in children exposed to a polluted urban atmosphere.

Southwest Metropolitan Mexico City (SWMMC) preadolescent children have been exposed to a highly polluted urban atmosphere most of their lives. The main objective of this study was to determine by nasal lavage (NAL) the acute inflammatory nasal influx elicited in these children upon exposure to three different polluted days. Ozone, the main criteria pollutant for SWMMC, varied both in the number of hours above the National Ambient Air Quality Standard (NAAQS), which is 0.12 ppm as a 1-h maximum concentration not to be exceeded more than once per year, and in the maximal concentrations in the preceding three NAL sampling dates. Nasal neutrophilic influx, the surface expression of the B2 integrin CD11b on the nasal polymorphonuclear leukocytes (PMNs), rhinoscopic findings, respiratory symptoms, and nasal cytologies were evaluated in the 38 exposed children and in the 28 control children living in a nonpolluted Pacific coast port. SWMMC children had an average daily outdoor exposure of 7.7 h and complained of nasal mucus secretion, epistaxis, intermittent nasal obstruction, diurnal cough episodes, and chest discomfort. Nasal mucosal atrophy by rhinoscopy was present in 37/38, and all children had an abnormal nasal cytology. Exposed children had significantly higher nasal PMNs and nasal PMN-CD11b expression than controls. PMN median values in exposed children were higher than controls on all sampling dates (November 12, p < .001; November 17, p < .001; and November 24, p < .00001). Interestingly, a lower nasal neutrophilic response (p < .0004) was recorded in the SWMMC children 18 h after exposure to the highest O3 concentrations (up to 0.307 ppm) and the largest number of hours with O3 > 0.12 ppm (7 h). The question of a competing inflammatory response at the bronchioalveolar level with structural damage is raised. These NAL findings underscore the need to restrict outdoor activity in SWMMC children during the months of greater potential exposure to ozone.

Air Pollutants↗

Prospective randomized comparison of cefepime and cefotaxime for treatment of bacterial meningitis in infants and children.

Ninety infants and children were prospectively randomized to receive cefepime (n = 43) or cefotaxime (n = 47) for therapy of bacterial meningitis. The two treatment groups were comparable in terms of age, duration of illness before enrollment, history of seizures, clinical status on admission, and etiology. Six (7%) patients died--two treated with cefepime and four treated with cefotaxime. Clinical response, cerebrospinal fluid sterilization, development of complications, antibiotic toxicity, and hospital stay were similar for the two treatment regimens. Concentrations of cefepime in cerebrospinal fluid varied from 55 to 95 times greater than the maximal MIC required by the causative pathogens. Audiologic and/or neurologic sequelae were found in 16% of the cefepime-treated patients and 15% of the cefotaxime-treated patients examined 2 to 6 months after discharge. We conclude that cefepime is safe and therapeutically equivalent to cefotaxime for management of bacterial meningitis in infants and children.

Adolescent↗

Anti-CD4 activity in circulating immune complexes in HIV-infected patients.

Levels of circulating immune complexes (CIC) measured by precipitation with 1.04 M ammonium sulfate ranged from 22 to 2,040 micrograms/ml in a group of 141 HIV-infected patients. CIC were elevated (> 200 micrograms/ml) in 72.2% of infected individuals. When analyzed for their HIV antigen composition, those CIC containing HIV antigens were found more frequently in patients clinically affected (68.6%) than in asymptomatic individuals (31.4%; p < 0.001). Anti-CD4 activity of 89 isolated CIC was detected in 43.8% of these patients, but only in 7.6% of the cases these CIC could bind to native CD4+ molecules. CIC with anti-CD4 activity could inhibit PHA stimulation of normal peripheral blood lymphocytes. Anti-CD4 activity in CIC was independent of the clinical and immunological status of HIV-infected patients.

Antibodies↗

[Alcohol consumption and glomerulonephritis caused by IgA mesangial deposits. (Berger's disease)].

Alcohol ingestion is considered as a possible pathogenic agent for Berger's disease, since Iga mesangial deposits have been described in liver cirrhosis. Aiming to assess this issue, 28 patients with Berger's disease (BD) and 40 patients with other glomerulopathies (NBD) were subjected to an enquiry about alcohol ingestion. Data was corroborated with 21 close relatives of BD patients and 34 relatives of NBD patients. No differences were observed in reported alcohol intake between BD patients and their relatives, however relatives of NBD patients underestimated their alcohol intake. No differences in alcohol intake, either self-reported or reported by relatives, were observed between BD and NBD patients. It is concluded that no differences in alcohol intake were observed between patients with Berger's disease and subjects with other glomerulopathies.

Adolescent↗

[Chronic intermittent peritoneal dialysis: a 12-year experience].

Since 1981, we have treated 46 adults aged 56 +/- 21 years, of whom 17 were diabetic, with intermittent peritoneal dialysis. Their mean time on dialysis has been 21 months with an accumulated experience of 493 months/patient. The program included 2 dialyses per week, 25 exchanges of 21 per session and 30 min of dwell time. Arterial pressure control has been satisfactory. Diabetic patients had lower levels of serum calcium, alkaline phosphatases and m-PTH. The incidence of peritonitis has been 1 episode/14 months/patient and the causative agent has been Staphylococcus aureus in 47% of episodes. Mean catheter duration has been 15 months and 1 episode/34 months/patient of exit site infection has been recorded and Staphylococcus aureus has been the causative agent in 83% of episodes. The risk of acquiring the first peritonitis was 12% at 3 months, 23% at 6 months and higher for non diabetic patients. Actuarial survival of treated patients at 12 and 24 months was 89 and 67% respectively. No differences in survival were recorded between diabetic and non diabetic patients. Fifty two percent of patients that dropped out continued on hemodialysis, 23% died, 11% abandoned treatment, 8% continued on chronic ambulatory peritoneal dialysis and 6% received a kidney allograft. We conclude that intermittent peritoneal dialysis is a good alternative treatment of chronic renal failure, even in diabetic patients.

Adult↗

Tolfenamic acid and mefenamic acid in the treatment of primary dysmenorrhoea.

The clinical efficacy of tolfenamic acid and mefenamic acid in the treatment of primary dysmenorrhoea was studied in a prospective, controlled, double-blind, cross-over study comprising 73 patients aged 13-39 with an average body weight of 56 kilos. The patients were randomized to receive either tolfenamic acid (200 mg t.i.d.) or mefenamic acid (500 mg t.i.d.) for 3 days, during 3 consecutive menstrual cycles each, in a sequential design A-B or B-A. At the beginning and at the end of each treatment period, 13 dysmenorrhoeic symptoms were evaluated on a visual analogue scale (lower back pain, interference with daily activities, nausea, vomiting, diarrhoea, headache, dizziness, fatigue, sweating, chills, hot flashes, depressant states, and mood swings). The data were analyzed by using two statistical models. The first one, for the 73 patients, by making paired comparisons regardless of treatment sequence. With respect to the initial values, the results showed that both drugs were statistically significant (P < 0.05) in reducing the intensity of the evaluated symptoms. When comparing both treatments, tolfenamic acid showed a significant difference as to interference with daily activities (P < 0.025) and hot flashes (P < 0.005). In the result analysis with the second model, the groups were divided according to the first assigned treatment and paired comparisons were made. It was observed that the group receiving tolfenamic acid in the last sequence reached a higher level of response and statistical significance was demonstrated in 8 of 13 evaluated symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

DNA content in non-Hodgkin's lymphoma. Comparison between flow cytometry and cytogenetics in fresh and paraffin-embedded tissue.

DNA content of 36-non-Hodgkin's lymphomas was analyzed by flow cytometry (FCM) and cytogenetics (CG), 21 in fresh and 15 in paraffin-embedded tissue. The results of both techniques were coincident in 60% of the fresh tissue samples and in 45% of the paraffin-embedded ones, the reason for this difference could be the poor resolution of DNA histograms from paraffin-embedded tissue. All samples judged as aneuploid by FCM were aneuploid also by CG. Some samples with a hyperdiploid population by CG gave a diploid population by FCM with a 'false' high DNA-synthesis (S) fraction. From a technical point of view, CG and FCM have to be performed on the same fresh tissue.

Cell Cycle↗

[Campylobacter fetus, an infrequent microbe, as a cause of spontaneous bacterial peritonitis in cirrhosis].

Campylobacter fetus has been implicated in the etiology of sepsis and bacteriemias in immunosupressed subjects. In a few cases, it has also been reported to be responsible for spontaneous bacterial peritonitis in cirrhotic patients. We describe the clinical picture of a woman with terminal liver cirrhosis who had bacteriemia and spontaneous bacterial peritonitis caused by this agent. We argue about the history of cleansing enemas and their probable role in the development of the infection. We stress the excellent response to the antibiotic treatment.

Adult↗

[Ascitic peritonitis due to Candida albicans].

We report a case of spontaneous peritonitis due to Candida albicans, in a diabetic patient with alcoholic liver cirrhosis, ascites, gastrointestinal bleeding from esophageal varices, sepsis, renal failure and encephalopathy. These factors, added to prolonged antibiotic therapy and instrumental manipulations, could have resulted in the colonization by Candida, usually described in secondary peritonitis, but perhaps underdiagnosed in cirrhotic patients with spontaneous peritonitis and severe multiorgan failure.

Ascites↗

Masking generates contiguous segments of metal-coated and bare DNA for scanning tunneling microscope imaging.

To date, no microscopic methods are available to confirm scanning tunneling microscope (STM) images of DNA. The difficulties encountered in repeating these images may be attributed to inadequate distribution of molecules on the substrate, poor adhesion to the substrate, or the low conductivity of the molecules. However, these factors are difficult to assess in an STM experiment where they may act simultaneously. A method to isolate these factors involves partly masking the deposited molecules before coating them with a conductive film to produce adjacent segments of coated and bare DNA after the mask is removed. The coated DNA segments are conductive and mechanically stable to allow easy identification of DNA by the STM. Furthermore, the path of a molecule can be traced from a coated to an uncoated region to test STM imaging of bare DNA. Masked preparations of DNA deposited on platinum/carbon-coated mica and highly oriented pyrolytic graphite were examined with a tunneling current 1000 times lower than the usual nanoamps. The tip apparently displaces molecules adsorbed to graphite to preclude imaging whereas more stably bound DNA on platinum/carbon-coated mica appears in reversed contrast.

Aluminum Silicates↗

Cholesterol metabolism in rat adrenal gland during reversible endotoxic shock.

The adrenal glands have a crucial role for survival during endotoxic shock. Cholesterol is the obligatory intermediary in corticosteroid biosynthesis; thus any alteration in either the availability of cholesterol or in the ability of the adrenal gland to use cholesterol would have a profound effect on corticosteroid production. We have studied the effect of Escherichia coli endotoxin on cholesterol metabolism, injecting lipopolysaccharide (1.6 mg/100 g body) from E. coli 0111:B4 into the tail vein of male Wistar rat. Previous studies from this laboratory have shown that this dose of lipopolysaccharide induces a reversible endotoxic shock. During reversible endotoxic shock there is an alteration in plasma cholesterol; plasma total-cholesterol levels increase mainly at 6-24 h post-lipopolysaccharide injection, whereas cholesterol in high-density lipoproteins shows no significant variations, except a slight but significant decrease at 24 h. The cholesterol content in adrenal gland is diminished in endotoxemic rat, this decrease is more important at 6-24 h after endotoxin injection. We have also measured the acyl-CoA:cholesterol O-acyltransferase (ACAT) and cholesterol-esterase (CEH) activity during endotoxic shock. ACAT activity decreases after lipopolysaccharide injection. ACAT activity in endotoxemic rats is approximately 35-40% of the activity in control rats. This decrease is due to a defect in the functional capacity of the enzyme, since with exogenous cholesterol there is no significant variation in the ACAT activity. CEH activity, in contrast, increases during endotoxic shock; it shows a maximum (twofold the activity seen in control rats) at 6 h after lipopolysaccharide injection. These results show that lipopolysaccharide injection modifies cholesterol metabolism in plasma and in the adrenal gland, either directly or by mediators.

Adrenal Glands↗

Serum lactate dehydrogenase level as a prognostic factor in Hodgkin's disease.

The efficacy of currently available treatments for Hodgkin's disease (HD) has led to a substantial modification in the prognosis of this disease; nevertheless there is still a group of patients that cannot be cured with conventional treatments and who will be candidates for alternative therapy. In the present work we analysed the prognostic influence of the most relevant clinico-biological characteristics of HD in a consecutive series of 137 patients diagnosed and treated in a single institution. Univariate analyses identified six variables with significant prognostic influence, both on achieving complete remission (CR) and overall survival (OS); LDH > 320 U ml-1, age > 45 years, stages IIB, III and IV, extranodal involvement, alkaline phosphatase > 190 UI dl and ESR > 40 mm h. In addition, Hb < 12.5 gr dl-1 and abdominal disease were statistically relevant for CR while a poor performance score (ECOG > or = 2) affected a lower survival. In the multivariate analysis only LDH, age and the clinical stage retained a significant prognostic influence for achieving CR, while the two first factors above, together with performance status were the variables with independent prognostic value with respect to OS. Moreover, only LDH > 320 U ml-1 had prognostic influence in the probability of relapse and disease free survival (DFS), both in the univariate and multivariate analyses. According to the three independent factors obtained in the multivariate analysis for CR (LDH, age and stage) a predictive model was established that allows the stratification of patients into two prognostic groups: one with poor prognosis that includes patients with the three adverse prognostic factors, or two if one of them was elevated LDH, and the other with good prognosis that includes the remaining patients. This model was also able to separate two independent groups of patients with respect to OS and to DFS. In conclusion, the present study shows that LDH is one of the most important prognostic factors in HD.

Adolescent↗