Biomedical subjects

S Guzmán

Publications and source records attributed to S Guzmán.

At least 19 recordsLinked to original sources

PubMed2003

Anti-inflammatory and immunomodulatory activities of polysaccharide from Chlorella stigmatophora and Phaeodactylum tricornutum.

Crude polysaccharide extracts were obtained from aqueous extracts of the microalgae Chlorella stigmatophora and Phaeodactylum tricornutum. The crude extracts were fractionated by ion-exchange chromatography on DEAE-cellulose columns. The molecular weights of the polysaccharides in each fraction were estimated by gel filtration on Sephacryl columns. The crude polysaccharide extracts of both microalgae showed anti-inflammatory activity in the carrageenan-induced paw edema test. In assays of effects on the delayed hyper-sensitivity response, and on phagocytic activity assayed in vivo and in vitro, the C. stigmatophora extract showed immunosuppressant effects, while the P. tricornutum extract showed immunostimulatory effects.

Adjuvants, Immunologic↗

PubMed2003

Risk progression to chronic Chagas cardiomyopathy: influence of male sex and of parasitaemia detected by polymerase chain reaction.

BACKGROUND: Polymerase chain reaction (PCR) allows detection of Trypanosoma cruzi in blood throughout the course of Chagas' disease. OBJECTIVE: To determine whether T cruzi DNA detected by PCR is associated with progression to chronic Chagas cardiomyopathy. DESIGN: Prospective cohort study. SETTING: A tertiary care centre in Argentina. PATIENTS: 56 consecutive patients with chronic T cruzi infection. METHODS: Clinical examination, ECG, and Doppler echocardiography were carried out at baseline and at the end of the follow up. Detection of T cruzi DNA by PCR amplifying a nuclear sequence was undertaken in all patients at baseline. MAIN OUTCOME MEASURES: Progression was defined as death from chronic cardiomyopathy or the presence of a new ECG or left ventricular echocardiographic abnormality at the end of follow up. RESULTS: The 56 patients (21 male, 35 female; mean (SD) age, 56.0 (11.3) years) were followed for a mean 936.3 (244.39) days. Progression to cardiomyopathy was detected in 12 patients (21.4%). Three of these patients died after baseline evaluation. Univariate analysis showed that a positive PCR (relative risk 4.09, 95% confidence interval (CI) 1.60 to 9.85) and male sex (5.00, 95% CI 1.65 to 15.73) were associated with progression. Multivariable logistic regression indicated that both sex and PCR were independent variables affecting the outcome. CONCLUSIONS: In a cohort of seropositive individuals, patients with T cruzi DNA detected by PCR and male patients were at higher risk of progression. These results highlight the importance of T cruzi in the pathophysiology of chronic cardiomyopathy.

Adult↗

PubMed2001

Antiinflammatory, analgesic and free radical scavenging activities of the marine microalgae Chlorella stigmatophora and Phaeodactylum tricornutum.

A pharmacological study of hydrosoluble and liposoluble extracts of the marine microalgae Chlorella stigmatophora and Phaeodactylum tricornutum indicated that hydrosoluble components of both species show significant antiinflammatory, analgesic and free radical scavenging activity. These activities were not detected in the liposoluble fractions.

Acetic Acid↗

PubMed2001

[Community diabetes educational intervention at the primary care level].

OBJECTIVE: To offer an educational alternative on diabetes, with the participation of patients with type 2 diabetes, their family members, and health care providers, adapted to local conditions and to these person's felt needs. METHODS: Focused on the primary-care level, this program was carried out in the health area of El Guarco, which is in the province of Cartago, Costa Rica. The first stage of the project included a qualitative study of the knowledge and practices of both patients and health care providers, looking at diabetes prevention and control and the local availability of foods. Based on those results, an educational methodology was developed, educational manuals were written, and courses for health care providers, patients, and patients' families were implemented. Other strategies were developed to make the effort sustainable. RESULTS: We found that patients did not associate family history or obesity with diabetes and that those persons were also confused about the symptoms of diabetes. Patients also received inconsistent nutrition messages from health care providers. Using the diabetes education manual as a base, the providers increased their knowledge of diabetes prevention, treatment, and education by an average of 85%. The diabetic patients who received educational training (mean age, 57.0 years, with a standard deviation of 8.9 years; 92% women) improved their glycemic control. Blood glucose levels decreased from 189 +/- 79 mg/dL (average and standard deviation) to 157 +/- 48 mg/dL (P < 0.05), and glycosylated hemoglobin (HbA1c) went from 11.3% +/- 2.4% to 9.7% +/- 2.3% (P = 0.05). There were no significant changes in body weight or lipid profile, except for triglycerides, which declined (P < 0.05). CONCLUSIONS: This educational program was successfully incorporated into the regular activities of the El Guarco-area health centers. The primary-care level is ideal for carrying out educational programs for diabetes treatment and early detection that are directed at patients, their families, and health care providers.

Adult↗

PubMed2000

[Change in metabolic risk factors in obese patients in treatment].

BACKGROUND: Obesity is a threat to health due to its association with cardiovascular risk factors. AIM: To assess the change in metabolic risk factors after weight reduction in obese patients. PATIENTS AND METHODS: A retrospective analysis of 277 obese patients (198 female) aged 39.5 +/- 12 years old, that completed a six month treatment period, consisting in a calorie restricted diet (800-1200 Kcal/day), physical activity, education and group psychological counseling. At the beginning and at the end of the program, weight, waist circumference, resting energy expenditure (REE), serum lipid profile, plasma glucose and plasma insulin levels were measured. RESULTS: During the treatment period, body mass index decreased from 38 +/- 7 to 33.2 +/- 6.4 kg/m2 with a weight loss of 11.7 kg, waist circumference decreased from 106.6 +/- 14.6 to 93.9 +/- 13.5 cm, REE decreased from 1774 +/- 383 to 1585 +/- 267 Kcal/day, blood glucose fell by 5.8%, plasma insulin fell by 40.4%, total cholesterol fell by 7.5%, LDL cholesterol fell by 8.7%, triglycerides fell by 26.6%, and total cholesterol/HDL ratio fell by 12.2%. CONCLUSIONS: Weight loss was associated with improvement in metabolic cardiovascular risk factors in obese patients.

Adolescent↗

PubMed1999

[Indication of gastrojejunostomy in unresectable pancreatic cancer].

BACKGROUND: Up to 20% of patients with pancreatic carcinoma subjected to a bilio digestive diversion, develop a delayed gastric emptying due to duodenal infiltration. However the role of prophylactic gastrojejunoanastomosis is not well defined. AIM: To compare the effects of gastrojejunoanastomosis performed as prophylaxis or as treatment for duodenal infiltration, in patients with unresectable pancreatic carcinoma. PATIENTS AND METHODS: Between 1983 and 1994, 44 gastrojejunoanastomosis were performed in patients with pancreatic carcinoma. In 24 patients the procedure was done as prophylaxis and in 20 as treatment of duodenal infiltration. Of these, three had been subjected previously to a bilio digestive diversion. Postoperative outcome and mortality of both groups of patients were compared. RESULTS: Both groups of patients had similar sex and age. Operative morbidity and mortality were 33% and 0% in the group with the prophylactic procedure and 35 and 10% in the group with duodenal infiltration. Oral feeding was started 6.5 and 6.9 days after operation, and hospital stay was 10.7 and 11.4 days in either group. At the moment of the analysis, 95.5% of patients had died. Survival was significantly longer in the group with the prophylactic procedure (337.2 and 116.9 days respectively, p < 0.01). Thirty eight percent of patients required a further admission to the hospital, but only 4.8% due to gastric retention. CONCLUSIONS: Gastrojejunoanastomosis is a good palliative procedure in patients with unresectable pancreatic carcinoma. It should be performed in every such patient who is subjected to a bilio digestive diversion and in whom a survival of some months can be predicted.

Adult↗

PubMed1998

New melampolides from Schkuhria schkuhrioides.

The novel melampolides (11R)-11,13-dihydro-schkuhriolide (7), (11S)-11,13-dihydro-schkuhriolide (8), and schkuhrioidiol (11), along with the known constituents, frutescin (1), schkuhriolide (2), frutescinic acid (4), allo-schkuhriolide (5), and epoxyschkuhriolide (6) were isolated from the aerial parts of Schkuhria schkuhrioides. The structures of the new compounds were determined by spectroscopic methods. Compounds 1, 2, 4, 5, and 6 displayed no significant cytotoxic or antimicrobial activities.

Animals↗

PubMed1998

[Negative appendectomy: experience at a university hospital].

BACKGROUND: Acute appendicitis still constitutes a difficult diagnostic problem. AIM: To assess the experience of an University Hospital in the diagnosis of acute appendicitis and to determine the rates of negative appendectomies. PATIENTS AND METHODS: The charts of 1,075 patients operated with the diagnosis of acute appendicitis, between 1993 and 1995, were retrospectively reviewed. All resected appendices were pathologically examined. Those cases in whom pathology did not confirm the clinical diagnosis were considered as a negative appendectomy. RESULTS: There was a 12.2% rate of negative appendectomies (18.9% in women and 6.2% in men). The difference between sexes disappears in patients over 40 years old. In 49% of patients, no abnormality was detected during the laparotomy. The most frequent differential diagnosis were gynecological illnesses or diseases of the colon. DISCUSSION: The rate of negative appendectomies can be reduced with a close clinical observation of patients during their hospitalization and the judicious use of diagnostic laparoscopy.

Adolescent↗

PubMed1997

Neuropeptide Y Y1 receptors are involved in the vasoconstriction caused by human sympathetic nerve stimulation.

Neuropeptide Y, a novel neurotransmitter, interacts with selective membrane receptors to cause vasoconstriction. Frequency- and concentration-dependent isometric contractions were observed in human inferior mesenteric artery and vein mounted rings that were stimulated with either electrical pulses (70 V, 0.5 ms, 2.5-20 Hz) or noradrenaline. The antagonism elicited by 100 nM tetrodotoxin and 1 microM guanethidine confirmed the neuronal and sympathetic origins of the vasomotor response. Incubation with BIBP 3226 ((R)-N2-(di-phenacetyl)-N-(4-hydroxyphenyl)-methyl-D-arginineam ide), a selective neuropeptide Y Y1 receptor antagonist, significantly reduced the vasoconstriction. The incomplete antagonist activity of BIBP 3226 tends to support the hypothesis of sympathetic co-transmission involving neuropeptide Y, adenosine 5'-triphosphate and noradrenaline. These findings were confirmed in parallel studies using rat superior mesenteric artery and vein ring preparations.

Animals↗

PubMed1997

[Occult gallbladder disease or microlithiasis in patients with acute pancreatitis: a frequent clinical event].

BACKGROUND: Patients with acute pancreatitis (AP) and a normal gallbladder by standard echographic evaluation may have "occult" gallbladder disease or microlithiasis with recurrent episodes of AP. AIM: To conduct a prospective evaluation of patients with the diagnosis of non-biliary AP in order to detect "occult" gallbladder disease and to compare its clinical presentation with that of biliary AP. PATIENTS AND METHODS: Patients admitted with the diagnosis of AP to a clinical hospital were included in the study. According to an abdominal ultrasound study, patients were classified as having or not cholelithiasis. A duodenal biliary drainage was performed in 15 patients with AP and without gallbladder stones. RESULTS: Patients without cholelithiasis had recurrent AP more often than patients with biliary AP (53 and 3.3% respectively). Excessive alcohol ingestion did not rule out the possibility of biliary etiology. In 6 patients, the analysis of duodenal bile showed cholesterol crystals, and cholecystectomy confirmed the existence of gallbladder disease in 5. All of them remained asymptomatic during a follow-up period of four years. One patient refused surgery, with subsequent development of gallstones and recurrent episodes of AP. In other 4 patients, gallbladder disease was confirmed by percutaneous gallbladder puncture or during cholecystectomy. No recurrence of AP were observed during the follow-up CONCLUSIONS: Microlithiasis or "occult" gallbladder disease accounts for at least 67% of the original "non-biliary" AP. Duodenal bile analysis is a useful and necessary technique for the evaluation of patients with "non-biliary" acute pancreatitis. Careful clinical and echographic follow-up of this subgroup of patients with AP is mandatory.

Acute Disease↗

PubMed1994

[Misoprostol--a PGE1 analog for induction of labor at term: comparative and randomized study with oxytocin].

The efficacy of misoprostol (a PGE1 analog) for induction of labor at term was compared with oxytocin by means of an open and randomized study in 153 pregnant women. A vaginal tablet containing 50 mcg of misoprostol was placed intravaginally in 78 women, the remaining 75 patients received i.v. oxytocin (2-32 mU/min). Bishop's score at the entry of the trial was similar in both groups. Delivery within 24 hours was achieved in 85.7% of the patients induced with misoprostol and in 64% of the patients infused with oxytocin (p < 0.05). Mean induction to delivery interval was significantly shorter in the misoprostol group (552 +/- 211 min; mean =SD) in comparison with that of the oxytocin group (745 +/- 292 min; mean +/- SD) (p < 0.05). The probability of still being pregnant at 24 hours (Life table analysis) was 14% (misoprostol group) and 26% (oxitocyn group). The difference was also statistically significant (p < 0.01). No undesirable side effects were observed in any of the patients, however, polisystoly (> 5 contractions in 10 min) was more frequently observed in the patients induced with misoprostol (24.6% vs 13.3%; p = NS). Cesarean section rate was higher in the oxytocin-induced patients (25.3%) than in the misoprostol-induced women (3.8%) (p < 0.05). The main cause of cesarean section was failure to progress in labor in both groups of patients. Neonatal outcome was good in both groups and there were no differences with respect to birthweight or to Apgar scores.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Intravaginal↗

PubMed1994

[Handling of Foley catheter regarding urinary retention syndrome following vaginal surgery].

The post surgical urinary retention syndrome is a frequent problem after vaginal surgery. In many medical centers it is used a transurethral vesical drainage for three to five days with or without vesical reeducation to prevent it. In order to determine the importance of the time of drainage and vesical reeducation in the presence of this syndrome 106 patients submitted to vaginal surgery were studied at random and prospectively, in our service. Patients were distributed in three groups: the first one, with 37 women in which the drainage was withdrawn at 24 hours; in the second group it was retired at 72 hours and in the third group the drainage was removed at 72 hours with previous vesical reeducation. The results show that those patients who were less time under vesical drainage presented a minor frequency of urinary retention after surgery (24.3% vs 30.7% and 43.7%).

Adult↗

PubMed1994

[Non Hodgkin lymphoma of the stomach: evaluation of surgical treatment in 24 patients].

This is a retrospective review of 24 patients with Non Hodgkin Lymphoma of the stomach operated between 1959 and 1991. The diagnosis was reached with a radiological study in 12 of 15 (80%) patients and with endoscopy in 11 of 16 (69%) of patients. Eleven of 14 (78%) preoperative biopsies available at the moment of the revision were positive for non Hodgkin Lymphoma. Clinical staging was performed using Ann Arbor Classification and the histological type was defined according to the Working Formulation. Diffuse large cell lymphoma (intermediate grade) was the most frequent histological subtype. Eleven patients were in clinical stage I, 10 patients in stage II and 3 in stage IV. Eight total gastrectomies and 16 subtotal gastrectomies were performed. Twenty one percent of patients had a postoperative complication and operative mortality was 12%. Stage I patients were treated exclusively with surgery and no recurrences were observed. Stage II patients received adjuvant chemotherapy, the tumor recurred in three and two died due to disease progression. Five years disease free survival was 64%. It is concluded that surgical treatment achieves a good disease control in stage I patients but must be complemented with chemotherapy in stage II tumors.

Actuarial Analysis↗

PubMed1994

[Pyogenic liver abscess. Experience with 50 cases].

During the last years the diagnosis and treatment of pyogenic liver abscess has changed substantially. The aim of this work is to report a retrospective analysis of 50 patients aged 24 to 87 years old, that presented with a pyogenic liver abscess and were treated in the last 13 years. The sensitivity for diagnosis of ultrasound examination, CAT scan and angiography was 68, 89 and 75% respectively. The origin of the abscess was detected at the biliary tree in 46% and remained unknown in 38%. Thirty one patients were operated, 13 were subjected to percutaneous drainage and 5 were treated only with antimicrobials. Forty percent of patients had a septic complication and 4 (8%) died. Mean hospital stay was 31 days for operated patients and 21 for the rest. The abscess recurred in seven patients and two of these had a gallbladder carcinoma. It is concluded that percutaneous drainage is an alternative to surgical treatment that must be accompanied by a careful diagnostic workup.

Adult↗

PubMed1994

[Choledochocele. Report of a case and review of the literature].

We report a 29 years old man with a choledochocele or type III choledochal cyst, an extremely rare condition. This was found during a cholecystectomy using a transcystic intra operative cholangiogram. A transduodenal sphincteroplasty was performed. The cyst diameter was 1.5 cm approximately and two 1-2 mm stones were extracted from its lumen. The chemical composition of these was different from those located in the gallbladder. The postoperative period was uneventful and the patient remains asymptomatic.

Adult↗

PubMed1994

[Evaluation of maternal and fetal blood flow indices in intrahepatic cholestasis of pregnancy].

To determine the existence of any change in the blood flow velocity indexes in patients with cholestasis of pregnancy, we studied a total of 51 pregnant women, (normal n = 15; anicteric cholestasis n = 21 and icteric cholestasis n = 15). There was no significant change in the parity, maternal age, gestational age, birth weight and in the apgar score among the groups. There was also no significant change in any of the blood flow indexes determined in the uterine artery, umbilical artery and fetal cerebral artery. We conclude that there are no significant changes in blood flow velocity indexes determined by doppler blood flow analysis in patients with cholestasis of pregnancy.

Adult↗

PubMed1994

[Gastrointestinal bleeding of unknown origin. Experience in 31 cases].

Thirty one patients with GI bleeding of obscure origin, defined as those with normal upper endoscopy and colonoscopy, were studied to know the yield of different diagnostic procedures. Seventeen patients consulted for hematochezia and bleeding less than 10 days of evolution in 71%. Small bowel X ray examination was performed in 14 cases with a diagnostic effectiveness (number of diagnosis/number or examination) of 14%, angiography was performed in 12 cases with an effectiveness 33%, radiolabeled erythrocyte scanning in 12 cases with an effectiveness of 75%, scintigraphy with pertechnetate in 6 cases with an effectiveness of 17% and intraoperatory endoscopy in 2 cases with an effectiveness of 50%. A definitive diagnosis was reached in 8 patients during the first admission and in 6 during the second admission. The principal etiologies were small bowel tumors in 3 cases, cecal ulcers in 2 and ileal diverticula in 2. Ten subjects were subjected to surgical and 2 to endoscopic treatment. Five patients with recurrent bleeding remain without diagnosis. It is concluded that radiolabeled erythrocyte scanning and angiography are effective examinations that should follow upper and lower endoscopies in the diagnosis of a concealed GI bleeding. When a diagnosis is not reached in the first admission, patients should be following with repeated diagnostic procedures.

Adolescent↗

PubMed1994

[Variability of measured energy expenditure in patients with acute pancreatitis: is it possible to obtain a reliable pathology factor for these cases?].

Energy expenditure was measured in 55 patients with acute pancreatitis, during variable periods ranging from 1 to 5 weeks and it was compared with estimated energy expenditure according to Harris Benedict equations. Patients with severe pancreatitis had similar measured and measured/estimated energy expenditure rations, compared to those with mild pancreatitis (1678 +/- 349.6 kcal/day and 1.1 +/- 0.19 vs 1632 +/- 383 kcal/day and 1.06 +/- 0.19). There was a high dispersion of measured/estimated rations (0.67 - 1.7) that precluded the calculation of a reliable energy expenditure correction factor for this disease. It is concluded that energy expenditure must be measured and not estimated, when planning an adequate nutritional support in patients with acute pancreatitis.

Acute Disease↗