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Biomedical subjects

M León

Publications and source records attributed to M León.

At least 19 recordsLinked to original sources
PubMed2006

[Variation of central corneal thickness in diabetic patients as detected by ultrasonic pachymetry].

OBJECTIVE: To prove the existence of a correlation between central corneal thickness and diabetes. METHODS: Ultrasound pachymetry measurements were made in 1,000 patients. The sample was divided into two groups of patients: 953 of them were non-diabetic patients, and 47 were diabetic patients. RESULTS: The average central corneal thickness in diabetic patients was 571.96 +/- 26.81 microns with a range between 514 and 626. The average central corneal thickness found in non-diabetic patients was 544.89 +/- 35.36 microns with range of 448 to 649. The increase in central corneal thickness found in diabetic patients compared to non-diabetic patients was statistically significant (p<0.001, Student "t" test). CONCLUSIONS: We found that diabetic patients had an increased central corneal thickness when compared with non-diabetic patients.

Adolescent↗
PubMed2006

First Spanish series of intestinal transplantation in adult recipients.

BACKGROUND: short-bowel transplantation has experienced a substantial growth worldwide following improved results from the late 1990's on, and its coverage by Medicare. According to the International Registry (1985-2005), a total of 1,292 intestinal transplants for 1,210 patients in 65 hospitals across 20 countries have been carried out thus far. OBJECTIVE: to know short-term (6 months) results regarding patient and graft survival from the first Spanish series of intestinal transplants in adult recipients. MATERIAL AND METHODS: we present our experience in the assessment of 20 potential candidates to short-bowel transplantation between June 2004 and October 2005. Of these, 10 patients were rejected and 4 were transplanted, which makes up the sample of our study. RESULTS: to this date 5 transplants have been carried out in 4 patients (2 retransplants, 2 desmoid tumors, 1 short bowel syndrome after excision as a result of mesenteric ischemia). Upon study completion and after a mean follow-up of 180 days (range 90-190 days) all recipients are alive, and all grafts but one (75%) are fully operational, with complete digestive autonomy. All patients received induction with alemtuzumab except one, who received thymoglobulin; in all induction was initiated with no steroids. CONCLUSIONS: intestinal transplantation represents a therapeutic option that is applicable in our setting and valid for recipients with an indication who have no other feasible alternative to keep their intestinal failure under control.

Adult↗
PubMed2004

Evaluation of a laboratory and full-scale microalgae pond for tertiary treatment of piggery wastes.

Piggery wastes tertiary treatment in laboratory and full-scale microalgal ponds was evaluated. COD, BOD, inorganic nitrogen and orthophosphate removals of up to 57%, 69%, 79% and 74%, respectively, were obtained. The effect of the hydraulic retention time (HRT) on removal efficiencies followed an exponential relationship. COD, BOD and orthophosphate removal rate decreased with increased effluent concentration while the inorganic nitrogen removal rate increased with an increasing effluent substrate concentration at inorganic nitrogen concentration values lower than 0.07 g l(-1). Values of maximum substrate removal rate, half rate constant, cell yield coefficient, endogenous constant and maximum specific growth rate were 7.1 +/- 0.5 d(-1), 0.21 +/- 0.02 g l(-1), 0.26 +/- 0.01 g VSS g(-1) COD, 0.012 +/- 0.001 d(-1)and 1.9 +/- 0.9 d(-1), respectively. At full-scale, effluent COD, BOD, MPN, inorganic nitrogen and orthophosphate decreased while pH and Chlorophyll a increased with the operation time. It was found that the use of the final effluent as drinking water did not affect pigs growth.

Animals↗
PubMed2001

Clinical features and long-term outcome of obesity-associated focal segmental glomerulosclerosis.

BACKGROUND: Several cases of obesity-associated focal segmental glomerulosclerosis (OB-FSG) have been reported but little is known about the clinico-pathological features of this entity and its long-term outcomes. METHODS: We studied 15 obese patients (BMI 35+/-5.2 kg/m(2)) with biopsy-proven FSG. They were compared with a control group of 15 non-obese patients with idiopathic FSG (I-FSG). RESULTS: Mean proteinuria at the time of renal biopsy was 3.1+/-2 g/24 h in OB-FSG; it reached the nephrotic range (> or =3.5 g/24 h) during follow-up in 12 patients (80%), but none of them had oedema, hypoproteinaemia, or hypoalbuminaemia. Proteinuria was more marked amongst I-FSG (6.5+/-4.2 g/24 h) and most of them developed oedema and biochemical nephrotic syndrome. Glomerulomegaly was observed in all renal biopsies from OB-FSG patients (mean glomerular diameter 256+/-24 microm in OB-FSG vs 199+/-26 microm in I-FSG, P<0.001). Twelve OB-FSG patients (80%) were treated with ACE inhibitors (ACEI) and proteinuria significantly decreased within the first 6 months of treatment but showed a later increase. None of the obese patients achieved a sustained weight loss. Seven (46%) patients with OB-FSG experienced a progressive renal insufficiency and five of them started intermittent dialysis. Kaplan-Meier estimated probabilities of renal survival after 5 and 10 years were 77 and 51%, respectively, in OB-FSG patients, and 52 and 30% in I-FSG (P<0.05). The risk of developing progressive renal failure among OB-FSG patients was statistically correlated with serum creatinine and creatinine clearance at presentation. CONCLUSIONS: OB-FSG indicates a poor prognosis with almost one-half of patients developing advanced renal failure. Knowledge of the clinico-pathological features of this entity (obesity, FSG lesions with glomerulomegaly, absence of nephrotic syndrome despite nephrotic-range proteinuria) should be helpful in establishing an accurate and early diagnosis.

Adult↗
PubMed1999

Basic phenotypic analysis of six novel yeast genes reveals two essential genes and one which affects the growth rate.

Phenotypic analysis was performed on six mutants of Saccharomyces cerevisiae deleted in one of the following open reading frames (ORFs), located on chromosome II: YBR254c, YBR255w, YBR257w, YBR258c, YBR259w and YBR266c. Disruption of the ORFs was carried out in the diploid strain FY1679 using the kanMX4 marker flanked by short sequences homologous to the target locus. Tetrad analysis following sporulation of the heterozygous disruptants showed that YBR254c and YBR257w are essential genes. YBR257w was later characterized and renamed POP4, its gene product being involved in 5.8S rRNA and tRNA processing (Chu et al., 1997). The tetrad analysis performed for the heterozygous disruptant for YBR266c showed that two of the four viable spores gave colonies of smaller size, reflecting a slower growth rate. Growth analysis of the disruptant haploids confirmed this defect at 30 degrees C and also at 15 degrees C. However, complementation tests failed to confirm that the deletion of YBR266c is responsible for this growth defect. Growth analysis of the disruptant haploid ybr255w(delta) showed a slower growth rate on YPD and minimal medium at 15 degrees C. Finally, no phenotypic effect could be detected associated to the disruption of ORFs YBR258c and YBR259w.

Chromosomes, Fungal↗
PubMed1999

Skin lesions in the ICU.

OBJECTIVE: The objective of this study is to identify the dermatological disorders (DDs) responsible for the most common skin lesions in the ICU, their incidence and their impact on mortality, degree of severity and length of stay in the ICU. DESIGN AND SETTING: We performed a 2-year prospective study in a general medical and surgical ICU including, exceptionally, paediatric cases. PATIENTS: We included all patients who presented skin lesions upon admission or developed them during their ICU stay. RESULTS: Forty-six patients (10% of all admissions) were enrolled, with 51 DDs. SAPS II score (43) and mean length of stay (19 days) were significantly higher than in the general group of ICU admissions. Differences in mortality rates (26% versus 29%) were not statistically significant. CONCLUSIONS: DDs are entities that should be borne in mind in the critically ill patient; their incidence is by no means negligible and makes careful examination of the skin mandatory both on admission and during a patient's ICU stay.

Adolescent↗
PubMed1998

[Diagnostic value of Gram staining of peri-catheter skin and the connection in the prediction of intravascular-catheter-related bacteremia].

BACKGROUND: To evaluate the diagnostic value of Gram stain of pericatheter skin swabs and the intravascular device hub in detecting catheter-related bacteremia (CRB) in critically-ill patients. METHODS: Over a 12-month period, 170 intravascular catheters (> 7 days in place) suspected as being the primary source of CRB were prospectively examined in adult patients admitted to 10 intensive care units of different hospitals in Spain. Blood cultures, Gram staining and culture of swabs obtained from skin entry side and catheter hub were performed before catheter removal. A semiquantitative culture of the catheter tip was carried out. Catheter-associated bacteremia was considered to be present if the same organism was isolated from the catheter tip, skin and/or hub, and blood cultures. RESULTS: The incidence rate of CRB was 15%. Staphylococcus epidermidis was the most frequently isolated microorganism. Considered together, the sensitivity, specificity, positive predictive value and negative predictive value for Gram staining of the skin and hub were 80, 81.9, 35.3 and 97.1%, respectively. CONCLUSIONS: The Gram stain of skin and hub swabs has a great utility in predicting CRB, specially in the absence of microorganisms. Gram stains of the above mentioned sites could be recommended as an easy and fast method to rule out the presence of CRB.

Adult↗
PubMed1998

[Detection of parvovirus B19 in patients of the Zulia State blood bank with different hematological alterations].

PURPOSE: To assess the seroprevalence of IgG and IgM specific for parvovirus B19 (B19) and its association with aplastic crisis developing in patients with different haematological disorders. PATIENTS AND METHODS: Fifty-three serum samples were evaluated, 24 from patients with aplastic crisis and 29 from others without such crises, all of them suffering from different haematological diseases diagnosed at the University Hospital of Maracaibo and the Zulia State Blood Bank, in Venezuela; 15 samples from healthy blood donors were examined as well. Indirect immunofluorescence technique was used in the study. Lymphocyte subsets were quantified in 10 of the patients with aplastic crisis by means of cytofluorometry. Serum proteins were assessed by electrophoresis in all samples. The statistical analysis was performed according to Student's t test and chi square, by applying the statix 4.0 and SAS programmes. RESULTS: Positive IgG was found in 20 of the 24 patients with aplastic crisis (83.3%), 20 of the 29 without crisis (68.9%) and 7 of the 15 healthy controls (46.6%). Positive IgM was found only in 2 of the 24 patients with aplastic crisis (8.3%). Both the patients without aplastic crises and the control groups were negative for PB19 IgM. The average CD4 and CD8 T lymphocyte count and the CD4-CD8 index in the patients studied were 454 CD4 cells/microL, 1,006 CD8 cells/microL and 0.5%, significantly different from the control group, whose figures were 860 CD4 cells/microL, 546 CD8 cells/microL and 1.6%. The average B lymphocyte count of the patients (628 cells/microL) was higher than that of the control group (349 cells/microL). The average NK cell count in the patient was 174 cells/microL, slightly below the control group (221 cells/microL). Mild beta-globulin decrease was found in the electrophoretic study of the serum proteins of the patients, along with significant increase of the total protein and the gammaglobulin fraction with regard to the control group. CONCLUSIONS: Higher PB19 IgG seropositivity was seen in the patients with aplastic crisis with respect to the control group, suggesting wider exposition to the virus among them with regard to the healthy population. Specific PB19 IgM was detected in 2 patients with immunodeficiency and aplastic crisis. A significant decrease of the CD4 and CD8 T-lymphocyte subsets, along with decreased CD4-CD8 quotient, were found in the aplastic crisis group, and an impairment of the immune response to the viral challenge can be inferred form this. The alterations of the serum proteins, together with the increased B lymphocytes, might suggest a polyclonal activation of these cells. The absence of other known lymphotropic viruses in most of the patients studied (50) show that the alterations found here are related to recent or past B19 infection.

Anemia, Aplastic↗
PubMed1997

[Treatment of asthmatic crises at a hospital emergency service. Are the protocols followed?].

Improper assessment and treatment of asthma attacks have been identified as causes of increased morbidity and mortality: several pneumological societies have therefore created and published guidelines for facilitating decision making and for preventing unnecessary failures of therapy. The objective of this study was to examine emergency department compliance with such guidelines in our hospital, comparing the performance of pneumologists and other specialists. We reviewed the records of 117 patients treated for acute asthma attacks in 1994 (87 women and 30 men, mean age 46 years); 37 patients were treated by pneumologists and 80 by other specialists. The two physician groups differed significantly with respect to initial assessment of severity, particularly in the recording of vital signs (p < 0.05) and in the examination of some signs such as the use of accessory musculature (38% versus 10%, for pneumologists and other specialists, respectively) or the presence of cyanosis (81% versus 55%). Other factors associated with risk of death were noted only occasionally. Peak flow meters were used with only 5 patients, all examined by pneumologists; on the other hand, arterial blood samples for gasometric measurements were taken from 97%, although only 24% met the criteria stipulated in the guidelines. Treatment evaluated against the guidelines was incorrect in 24%, with no significant differences between pneumologists and other specialists. We conclude that: 1) the emergency clinical assessment and treatment of patients presenting with acute asthma attack is inadequate for a large proportion of patients, as the recommendations of consensual guidelines are habitually ignored, and 2) although there are differences in the management of these patients by pneumologists and other emergency room specialists, the former do not generally do a better job of following the guidelines.

Adolescent↗
PubMed1997

Extubation outcome after spontaneous breathing trials with T-tube or pressure support ventilation. The Spanish Lung Failure Collaborative Group.

A 2-h T-tube trial of spontaneous breathing was used in selecting patients ready for extubation and discontinuation of mechanical ventilation. However, some doubt remains as to whether it is the most appropriate method of performing a spontaneous breathing trial. We carried out a prospective, randomized, multicenter study involving patients who had received mechanical ventilation for more than 48 h and who were considered by their physicians to be ready for weaning according to clinical criteria and standard weaning parameters. Patients were randomly assigned to undergo a 2-h trial of spontaneous breathing in one of two ways: with a T-tube system or with pressure support ventilation of 7 cm H2O. If a patient had signs of poor tolerance at any time during the trial, mechanical ventilation was reinstituted. Patients without these features at the end of the trial were extubated. Of the 246 patients assigned to the T-tube group, 192 successfully completed the trial and were extubated; 36 of them required reintubation. Of the 238 patients in the group receiving pressure support ventilation, 205 were extubated and 38 of them required reintubation. The percentage of patients who remained extubated after 48 h was not different between the two groups (63% T-tube, 70% pressure support ventilation, p = 0.14). The percentage of patients falling the trial was significantly higher when the T-tube was used (22 versus 14%, p = 0.03). Clinical evolution during the trial was not different in patients reintubated and successfully extubated. ICU mortality among reintubated patients was significantly higher than in successfully extubated patients (27 versus 2.6%, p < 0.001). Spontaneous breathing trials with pressure support or T-tube are suitable methods for successful discontinuation of ventilator support in patients without problems to resume spontaneous breathing.

Aged↗
PubMed1997

[Clinical and epidemiological study of blood donors seropositive for Trypanosoma cruzi].

BACKGROUND: The prevalence of positive antibodies for Chagas disease in a blood bank of a public hospital in Santiago is 1.2%. These positive individuals should be informed about their condition and further studied. AIM: To perform a serological confirmation, an epidemiological and clinical assessment of blood donors seropositive for Chagas disease in a blood bank of Santiago. SUBJECTS AND METHODS: One hundred eleven seropositive donors, detected between 1994 and 1996, were studied. Serological reactions were confirmed with ELISA and indirect immunofluorescence reactions. Those confirmed as positive were subjected to a clinical-epidemiological questionnaire, physical examination, EKG and barium enema or swallow according to symptoms. RESULTS: Seventy individuals were confirmed as positive for Chagas disease. Most of them lived at least once in an endemic zone for Chagas disease or in a sun-dried clay brick house. Forty-percent of individuals knew reduviid bugs and 14% had been bitten by these insects. Twenty six percent of these subjects had an abnormal EKG (61% with bradycardia). No digestive diseases attributable to Chagas disease were detected. CONCLUSIONS: The high prevalence of problems attributable to Chagas disease among seropositive blood donors underscores the need of an epidemiological follow up of these individuals.

Adult↗
PubMed1996

Prediction of the need for mechanical ventilation in acute severe asthma.

Unwarranted long delays in treating asthmatic patients requiring assisted mechanical ventilation (AMV) could be associated with higher death rates. The objective of the study was to identify which were the best predictive characteristics of patients with acute severe asthma (ASA) who required AMV. For this purpose, we reviewed retrospectively the hospital record of every patient with ASA admitted to the intensive care unit (ICU) from 1981 to 1991 (38 with AMV and 38 without AMV). Twenty-seven variables were obtained from the history, physical examination, laboratory tests, blood gases and treatment. Using a multivariate discriminant analysis, the most powerful predictor of patients needing AMV was a function that consisted of eight variables: arterial pH, number of previous admissions to ICU, asthma severity, time elapsed since last visiting a physician, respiratory rate, age, systolic pressure and heart rate. With this function, 33 of 38 mechanically ventilated patients were well classified (sensitivity: 0.89) and the overall accuracy of the test was 92% (70 out of 76 cases). The positive and negative predictive values of the function for mechanical ventilation were 0.96 and 0.90, respectively. We conclude that the application of the calculated final discriminant function could be appropriate to decide which patients with ASA require AMV.

Acute Disease↗
PubMed1996

[Direct percutaneous endoscopic jejunostomy, variation of the technique of gastrostomy].

Percutaneous endoscopic gastrojejunostomy is a percutaneous endoscopic gastrostomy derived technique, that is widely employed. However it has a high incidence of mechanic complications. Percutaneous endoscopic jejunostomy direct access, improves these problems and allows to apply this technique in patients with previous gastric resection or with other gastric diseases that contraindicate percutaneous endoscopic gastrostomy. We describe, for the first time in our country, a direct percutaneous endoscopic jejunostomy placement.

Gastrostomy↗
PubMed1995

Effects of body-weight loss and captopril treatment on proteinuria associated with obesity.

We have identified 17 obese patients (body mass index, BMI, 37.9 +/- 4.1) with proteinuria > 1 g/day (1.3-6.4 g/24 h, mean 3.1 +/- 1.7). Their age was 34-70 years (48.3 +/- 10); 11 were females and 6 males. Six patients had only one functioning kidney and a sleep apnea syndrome had been diagnosed in 5. Renal biopsies, obtained in 5 cases, showed focal glomerulosclerosis in 2 cases, minimal changes in 2 and mesangial proliferation in 1. Nine patients (group 1) were treated with hypocaloric diets; body weight significantly decreased (BMI 37.1 +/- 3, 34 +/- 3.5 and 32.6 +/- 3.2 at 0, 6 and 12 months, respectively) as well as proteinuria (2.9 +/- 1.7, 1.2 +/- 1 and 0.4 +/- 0.6 g/24 h). There was a significant correlation between body weight loss and decrease in proteinuria (r = 0.69, p < 0.05). Eight patients (group 2) were treated with captopril, without dietary changes. BMI remained stable but proteinuria showed a dramatic decrease, similar to that in group 1 (3.4 +/- 1.7, 1.2 +/- 0.9 and 0.7 +/- 1 g/24 h, respectively). Renal function remained stable in both groups. In summary, both body weight loss and captopril treatment can induce a sharp decrease in obesity-related proteinuria.

Adult↗
PubMed1995

[Cushing's syndrome associated with a metastatic medullary carcinoma of the thyroid. A report of 2 cases and a review of the literature].

An ectopic Cushing syndrome (CS) caused by a medullary thyroid carcinoma (MTC) is an exceptional observation. Two patients are here reported with metastatic MTC, who developed CS two years after the thyroid cancer was diagnosed. A review is also made of clinical and biochemical characteristics of cases with MTC associated with ectopic CS reported in the literature and it is concluded that the cortico-adrenal function in follow-up should be monitored in patients with this type of cancer.

Aged↗
PubMed1994

[Pulmonary infection by M. kansasii following cytomegalovirus pneumonia in a kidney transplant patient].

We report the case of a 55-year-old woman who developed a lung infection by cytomegalovirus (CMV) with overlapping infection by M. kansasii after receiving a kidney transplant. The second germ infection was subclinical, with unusual nodules showing in X-rays. We describe procedures used and diagnostic criteria applied in determining the nature of this atypical mycobacteria in an immunosuppressed patient. The outcome was good with treatment that included rifamycin, cyprofloxacin, streptomycin and ethambutol.

Biopsy, Needle↗
PubMed1994

[S. pneumoniae sternoclavicular arthritis in a patient with HIV infection].

HIV infection is a predisposing factor for pneumococcic infection. While pneumonia is the most frequent location, other locations (articular, meningeal, endocardiac, etc) have been less frequently described. Among the articular infections described in patients with HIV infection, the sternoclavicular affection is extremely rare and it usually develops in association with parenterally drug addiction, being Staphylococcus aureus and Pseudomonas aeruginosa the most frequently germs involved. We describe the first case of sternoclavicular arthritis by Streptococcus pneumoniae in a patient with HIV infection. In our case, the chronic hepatopathy associated to alcohol consumption is a predisposing factor related to the pneumococcic infection. Our case suggests the need to formally investigate the HIV infection in young patients with invasive pneumococcic infection.

Adult↗