PubMed Health⌕ Search

Biomedical subjects

B Rincón

Publications and source records attributed to B Rincón.

10 recordsLinked to original sources
PubMed2005

Performance and microbial communities of a continuous stirred tank anaerobic reactor treating two-phases olive mill solid wastes at low organic loading rates.

A study of the performance and microbial communities of a continuous stirred tank reactor (CSTR) treating two-phases olive mill solid wastes (OMSW) was carried out at laboratory-scale. The reactor operated at a mesophilic temperature (35 degrees C) and an influent substrate concentration of 162 g total chemical oxygen demand (COD)L(-1) and 126 g volatile solids (VS)L(-1). The data analyzed in this work corresponded to a range of organic loading rates (OLR) of between 0.75 and 3.00 g CODL(-1)d(-1), getting removal efficiencies in the range of 97.0-95.6%. Methane production rate increased from 0.164 to 0.659 L CH(4)L(reactor)(-1)d(-1) when the OLR increased within the tested range. Methane yield coefficients were 0.225 L CH(4)g(-1) COD removed and 0.290 L CH(4)g(-1) VS removed and were virtually independent of the OLR applied. A molecular characterization of the microbial communities involved in the process was also accomplished. Molecular identification of microbial species was performed by PCR amplification of 16S ribosomal RNA genes, denaturing gradient gel electrophoresis (DGGE), cloning and sequencing. Among the predominant microorganisms in the bioreactor, the Firmicutes (mainly represented by Clostridiales) were the most abundant group, followed by the Chloroflexi and the Gamma-Proteobacteria (Pseudomonas species as the major representative). Other bacterial groups detected in the bioreactor were the Actinobacteria, Bacteroidetes and Deferribacteres. Among the Archaea, the methanogen Methanosaeta concilii was the most representative species.

Anaerobiosis↗
PubMed2005

A study of the natural biodegradation of two-phase olive mill solid waste during its storage in an evaporation pond.

A study of the natural biodegradation of two-phase olive mill solid waste (OMSW) during its storage in an evaporation pond was carried out. This system is traditionally used as the final disposal of this waste or constitutes a previous stage before being processed by cogeneration or anaerobic digestion processes. A laboratory-scale pond with a total volume of 520 l was used. The experiment was carried out between December 2002 and August 2003 covering a total period of 269 days. During the experiment, the variations of temperature (outside and inside the pond), the effective volume of the OMSW in the pond, moisture content, total solids (TS), volatile solids (VS), the total chemical oxygen demand (TCOD), total volatile acids (TVA), pH and cumulative methane production as a function of the operation time were evaluated. The experimental results obtained showed that the characteristics of the two-phase OMSW in the pond were dependent on the time of operation and temperature. During the experiment, three periods were clearly observed and differentiated: (a) An initial period with a rapid reduction of moisture content and effective volume, with an increase of TS, VS and TCOD removals, a decrease of pH and an increase of TVA and methane production until day 21. (b) A second period of slow decrease of moisture content and effective volume, due to the decrease of the ambient temperature. This period took place between day 21 and days 120-150 of assay, and it was characterised by a slight change in the OMSW properties. (c) A third period where the characteristics of the waste in the pond changed considerably due to the increase of the temperature outside the pond. The methane gas production also showed an increase due to the increase of methanogenic activity with the increase of temperature. An empirical model to describe the changes of two-phase OMSW characteristics and methane production with the operation time was developed. The proposed model, based on the use of polynomial equations, took into account the influence of the temperature and fit adequately into the experimental results obtained. It was found that the pond could probably be used as preliminary treatment of two-phase OMSW before its anaerobic digestion process, because a maximum conversion of organic matter to TVA was obtained after an operation time of around 200 days.

Biodegradation, Environmental↗
PubMed2005

[Doxazosine associated to renin-angiotensin blockers and calcioantagonists in chronic renal failure patients].

OBJECTIVE: To evaluate the safety and effectiveness of the alfa-blocker doxazosin GITS in CRF patients. DESIGN AND METHODS: The study recruited 203 CRF patients (creatinine > 1,4 mg/dl for males, creatinine > 1,2 mg/dl for females, or creatinine clearance < 80 ml/min). All patients were receiving ACE inhibitores (63.4%) or angiotensin II antagonist (36.6%) therapy but they had higher blood pressure than recommended for CRF (130/85 mmHg). Patients were clinically evaluated 1, 3 and 6 moths after starting treatment with lercanidipine (10 mg once daily). Patients with high blood pressure in spite of combined therapy with two drugs added doxazosin GITS 4-8 mg once daily to treatment. RESULT: 57 patients rendered evaluable for the study (age 64.8 +/- 12.7 years, 47.4% males and 52.6 females). BP significantly decrease from 164 +/- 17/92 +/- 9 mmHg to 135 +/- 13/78 +/- 8 mmHg. 67.6% patients showed a significant BP reduction and 32.4% gets optimal BP control (< 130/85 mmHg). Two patients (3.6%) showed untoward effects. No biochemical changes were detected. CONCLUSIONS: Doxazosin showed a good antihypertensive effect in CRF patients when used as third drug in resistant severe hypertension. It has a good tolerability profile and showed a neutral profile on biochemical parameters.

Antihypertensive Agents↗
PubMed2004

Normal expression of IFN-gammaR in four patients with uncommon mycobacterial infection phenotypes.

Several primary immunodeficiency diseases affecting the interleukin 12/interferon gamma (IFN-gamma) pathway have been identified, most of them characterized by recurrent and protracted infections produced by intracellular microorganisms, particularly by several species of mycobacteria. In the present study we analyzed the expression of IFN-gamma receptor (IFN-gammaR) and signal transducer and activator of transcription 1 (STAT-1) in 4 children with Mycobacterium tuberculosis infection of uncommon clinical presentation. These molecules were evaluated by flow cytometry and Western blotting in B cells transformed with Epstein-Barr virus and mutations were scanned by single-strand conformational polymorphisms and DNA sequencing. The expression of IFN-gammaR1 was normal in all 4 patients. The genetic analysis of IFN-gammaR1 and IFN-gammaR2 coding sequences did not reveal any mutation. The expression of the STAT-1 molecule was similar in patients and healthy controls; however, when the phosphorylation of this transcription factor in response to IFN-gamma activation was evaluated by Western blot, a significant lower signal was evident in one patient. These data indicate that there are no alterations in the expression or function of the IFN-gammaR chains in these patients. However, the low level of STAT-1 phosphorylation found in one of these patients might be explained by a defect in one of the molecules involved in the signal transduction pathway after IFN-gamma interacts with its receptor. In the other three patients the inability to eliminate the mycobacteria may be due to a defect in another effector mechanism of the mononuclear phagocytes.

Blotting, Western↗
PubMed2004

[Lercanidipine in diabetic patients with renal failure].

OBJECTIVE: To evaluate the safe use of a new calcium channel blocker, lercanidipine, in diabetic chronic renal failure (CRF) patients. DESIGN AND METHODS: The study recruited 42 diabetic CRF patients (creatinine > 1.4 mg/dl for males, creatinine > 1.2 mg/dl for females, or creatinine clearance < 70 ml/min). Mean age was 68.2 +/- 9.1 years. 53.8% were males and 46.2% females. Three patients were type 1 diabetics and 39 ones were type II. All patients were receiving ACE inhibitors (67.4%) or angiotensin II antagonist (32.6%) therapy but they had higher blood pressure than recommended for CRF patients (130/85 mmHg). No patients were under diuretic treatment. Patients were clinically evaluated 1, 3 and 6 months after starting treatment with lercanidipine. Samples for urine and blood examination were taken during the examination. When needed, a third drug was added to treatment, excluding diuretics. Creatinine clearance was measured using 24 h urine collection. RESULTS: BP significantly decrease from 163 +/- 18/90 +/- 8 mmHg to 134 +/- 12/77 +/- 9 mmHg. One half of patients showed significant reduction of blood pressure, 26.7% reached the target blood pressure (< 130/85 mmHg) and 20.0% gets optimal BP control (< 130/85 mmHg). No one patient showed untoward effects. No edema was detected nor adverse effects related to vasodilatation were found. Plasmatic creatinine did not change (1.9 +/- 0.5 baseline vs 1.8 +/- 0.5 mg/dl) and creatinine clearance increased at the end visit (40.1 +/- 14.5 baseline vs 45.4 +/- 18.2 ml/min) but the difference was not significant. Proteinuria was unchanged. CONCLUSIONS: Lercanidipine showed a good antihypertensive effect in diabetics CRF patients. It has a good tolerability profile and showed neutral effect on plasmatic lipids. Neither impairment of renal function nor increment in proteinuria were detected.

Aged↗
PubMed1992

Renal failure in temporal arteritis.

We report a case of biopsy-proven temporal arteritis and polymyalgia rheumatica with improved clinical symptoms with steroid treatment but with subsequent renal failure while on steroids. Kidney biopsy showed focal segmental necrotizing glomerulonephritis with crescents and small-vessel vasculitis. Treatment with methylprednisolone and cyclophosphamide achieved normalization of renal function. We emphasize the importance of kidney biopsy because of its therapeutic implications. The previous literature concerning renal disease in temporal arteritis is discussed.

Aged↗
PubMedDate not supplied

[Apolipoprotein C-II and C-III anomalies in normolipemic and hyperlipemic patients with chronic kidney failure].

The high incidence of arteriosclerotic disease in patients with chronic renal failure seems to be due to certain peculiarities in their lipid metabolism. These are principally a disorder in the transportation of lipoproteins and a concomitant defect in triglyceride metabolism causing an accumulation of triglyceride-rich-lipoproteins which predispose to atherosclerosis. We studied the disturbances in concentration of apolipoproteins, notably Apo C-II and C-III, which modulate the activity of lipoprotein lipase (LPL), in patients with chronic renal failure (CRF) without replacement therapy and in hemodialysis patients with and without hyperlipidemia. LPL hydrolyses triglycerides in the lipoprotein-triglyceride (LPRTG) core. The main lipid parameters were measured in 4 groups of normolipidemic and hyperlipidemic patients with and without CRF in comparison with healthy controls. We found that the lipolytic activity index (A-I/C-III) was decreased, and Apo C-III levels were increased, in patients with CRF and patients on HD, including normolipidemic patients. We conclude that high Apo C-III levels are found in uremic patients before starting dialysis and do not change during dialysis treatment. This increase could be one of the initial causes of impaired triglyceride catabolism and LPRTG accumulation even in normolipidemic patients with CRF and may be one explanation of the high mortality from cardiovascular disease in these patients.

Apolipoprotein C-II↗