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A Guerra

Publications and source records attributed to A Guerra.

At least 19 recordsLinked to original sources
PubMed1995

Effects of urinary macromolecules on the nucleation of calcium oxalate in idiopathic stone formers and healthy controls.

Urinary macromolecules have attracted great interest because of their possible role as both promoters and inhibitors of calcium oxalate (CaOx) crystallization and it remains unclear whether there is any difference, in their nucleating activity, between stone formers and controls. We selected 9 male idiopathic CaOx stone formers whose 24-h urines presented no evidence of common urinary stone risk factors such as hypercalciuria, hyperoxaluria, hyperuricosuria, hypocitraturia, hypomagnesiuria or low glycosaminoglycans excretion and 12 male controls (matched for age and body weight) whose 24-h urines did not differ from those of stone formers. The study of urinary CaOx nucleation was made in freshly voided overnight urines whose biochemical composition was almost identical in the two groups. In filtered (0.22 micron) and ultrafiltered (10 kDa) urine we performed an oxalate tolerance test to determine the permissible increment of oxalate, the oxalate level for nucleation and the permissible increment of CaOx relative supersaturation (CaOx RS). In filtered urine from stone formers the permissible increment of oxalate was lower than controls (30 +/- 10.2 vs. 46.7 +/- 9.7 mg/l, P = 0.001), the oxalate level for nucleation was lower (64.4 +/- 14.2 vs. 79.5 +/- 15.6 mg/l, P = 0.035) and the permissible increment of CaOx RS was also lower (9.71 +/- 2.59 vs. 13.39 +/- 3.62, P = 0.018). In ultrafiltered urine these differences disappeared because the removal of macromolecules in stone formers significantly enhanced the oxalate-tolerance values. The difference between the change of the oxalate permissible increment of filtered and ultrafiltered urine allowed a distinction to be made between stone formers and controls that was not feasible in other ways (7.6 +/- 5.3 vs. 3.3 +/- 5.9 mg/l, P < 0.0001). The study suggests that, in idiopathic CaOx stone formers free from common urinary risk factors of CaOx crystallization, there is an increased tendency for CaOx nucleation in urine, which is mediated by macromolecular components.

Adult↗
PubMed1995

Stress radiography in the diagnosis of anterior cruciate ligament deficiency.

A prospective study was carried out to test the sensitivity and specificity of stress radiography in detecting anterior cruciate ligament deficiency in both knees of 116 patients using the Telos device. In 47 of these a total or partial rupture of the anterior cruciate ligament was diagnosed by arthroscopy, while the ligament was intact in the remaining 69 patients. The mean difference in radiological translation between the injured and the normal knee was greater than 5 mm (p < 0.001) in those with anterior cruciate deficiency, and less than 3 mm in the others. A differential displacement of up to 3 mm was considered normal. The sensitivity of the method was less than 67% and the specificity was 100%. Clinical diagnosis had a sensitivity of 70.2% and a specificity of 98.5%. Our findings suggest that, although a differential translation of more than 3 mm can be diagnostic, smaller differences do not rule out anterior cruciate deficiency.

Anterior Cruciate Ligament↗
PubMed1995

Tolerance of intravitreous interleukin-1 beta in the treatment of experimental vitreous hemorrhage.

We investigated the tolerance of human recombinant interleukin-1 beta (IL-1 beta) injected intravitreously and its putative role in the clearance of experimental vitreous hemorrhages. Three groups of 10 pigmented rabbits each were injected intravitreously with 0.1 ml autologous whole blood. Mean fundus revisualization times after blood clouding were as follows: group 1 (controls, blood injection only), 5.3 weeks; group 2 (100 units of IL-1 beta injected intravitreously 7 days after blood injection), 3.3 weeks; group 3 (1,000 units of IL-1 beta injected intravitreously 7 days after blood injection), 3.2 weeks. Group 4 (10 rabbits) was injected only with 1,000 units of IL-1 beta. Clinical examinations showed a transient mild inflammatory reaction in group 2 and a transient severe reaction in groups 3 and 4. Vitreous opacities, a whitish retinal reaction and vascular changes were seen in group 4. Electroretinography did not show a b-wave decrease in any group. These results suggest that low concentrations of IL-1 beta may be useful for nonsurgical treatment of human vitreous hemorrhage.

Animals↗
PubMed1995

Microsatellite DNA polymorphism analysis in a case of an illegal cattle purchase.

A case of illegal cattle purchasing is presented. Basque country police submitted six blood samples: three from the allegedly stolen animals and three from the putative mothers. Four polymorphic DNA loci were analyzed to establish the parental relationship. From the case investigation the maternity of the alleged cattle was determined.

Alleles↗
PubMed1994

[Pneumatosis intestinalis: a rare and difficult problem].

We present a case of a 74-year-old-woman who developed 3 episodes of intestinal pneumatosis, 2 times complicated by pneumoperitoneum, with consequent lethal outcome after 4 months. Intestinal pneumatosis, according to the literature, is a difficult and rare problem, associated with a large number of current diseases, can be complicated by pneumoperitoneum, mostly without clear etiology, whose treatment remains empirical (antibiotics, O2-therapy), not excluded laparotomy, if the clinical situation requires it.

Aged↗
PubMed1994

[Mesenteric infarct in acute mesenteric vein thrombosis].

Mesenteric venous thrombosis is an infrequent but distinct form of intestinal ischemia. We report 2 cases of acute mesenteric venous thrombosis, treated successfully by carrying out intestinal resection and postoperative anti-coagulation (Heparin, Sintrom). Both patients were diagnosed in the operating room. Improvements in computed tomography may identify patients earlier in their clinical course, heparin has both a primary therapeutic role in early disease and a postoperative adjunctive role in advanced disease. With such care, these patients can expect an acceptable prognosis.

Adult↗
PubMed1993

Calcium and sodium handling during volume expansion in essential hypertension.

To evaluate the actual role of extracellular fluid volume (ECFV) expansion per se in modulating the rate of urinary calcium excretion, a thermoneutral water immersion (WI) study was conducted in 10 normal subjects and 30 patients with essential hypertension. Central hypervolemia by 2 hours of WI caused a significant diuretic and natriuretic response (P < .005) in normal subjects; no significant changes were detected in urinary calcium and magnesium excretion. WI provoked either an appropriate or exaggerated natriuresis (P < .001) in 21 hypertensive patients; these subjects also exhibited a highly positive correlation between urinary sodium and calcium excretion during WI (P < .001). In the remaining nine hypertensive patients, WI produced a significant diuretic response, but a barely discernible (P = NS) natriuresis (inappropriate response). These subjects also exhibited a significant reduction of urinary calcium (P < .001) and magnesium (P < .01) excretion. The data indicate that (1) volume expansion per se may have a role in regulating calcium excretion in hypertensive subjects; (2) a calcium leak may be attributable to a close relationship between urinary sodium and calcium metabolism, and causally related to a disturbance of sodium and volume homeostasis in hypertension.

Adult↗
PubMed1993

Efficacy and tolerability of nimesulide and lysine-acetylsalicylate in the treatment of paediatric acute upper respiratory tract inflammation.

In a single-blind study that recruited 70 children aged 5 to 12 years with acute upper respiratory tract infection and fever (in- or outpatients), the effectiveness and tolerability of nimesulide 50 mg/dose were compared with those of lysine-acetylsalicylate 720 mg/dose (equivalent to 200mg of salicylate). Each agent was administered to 35 children, and both groups were simultaneously treated with antibiotics. General and respiratory symptoms were evaluated daily. Nimesulide treatment was associated with a more rapid and greater antipyretic effect than lysine-acetylsalicylate: 94% of nimesulide recipients and 77% of lysine-acetylsalicylate recipients were considered by physicians to have a good or very good response to therapy (p < 0.05). Furthermore, fewer doses of nimesulide than lysine-acetylsalicylate were required for resolution of fever and associated symptoms (nausea, vomiting, headache). The 2 drugs had similar global efficacy. Tolerability was good or very good in all patients.

Acute Disease↗
PubMed1993

Randomized prospective study of a nonthiazide diuretic, indapamide, in preventing calcium stone recurrences.

We examined the biochemical changes and the efficacy of indapamide in the prevention of calcium stone recurrences. Seventy-five patients with calcium nephrolithiasis and hypercalciuria were randomly assigned to three different therapies: diet and fluid (group A), diet and fluid plus indapamide 2.5 mg/day (group B), and diet and fluid plus indapamide 2.5 mg/day plus allopurinol 300 mg/day (group C). Before treatment and after 6, 12, 24, and 36 months of therapy, we evaluated blood pressure, serum and urine risk parameters (including relative supersaturations of calcium oxalate, calcium phosphate and uric acid), stone rate, and the proportion of calculi-free patients. During the 3 years of treatment, urinary calcium greatly decreased in groups B and C, dropping to 50% of the pretreatment values; urinary oxalate also significantly declined in group B (-24%) and group C (-27%). Relative supersaturations of calcium oxalate and calcium phosphate decreased to the same extent in groups B and C (about one-half of the pretreatment value), and relative supersaturation of uric acid was particularly reduced in group C (-65% of the pretreatment value). The stone rate improved in all three groups (p < 0.005), but using actuarial analysis in the evaluation of calculi-free patients, indapamide, and indapamide plus allopurinol groups were found to have a significantly more favorable effect than diet and fluid treatment (p < 0.02), without any difference between the two drug groups. Because indapamide has fewer side effects than thiazide diuretics, we conclude that indapamide could be an interesting alternative to thiazides in the prevention of calcium stones in hypercalciuric patients.

Adult↗
PubMed1993

[Massive lower digestive hemorrhage caused by colonic ulcers secondary to cholesterol embolism].

Cholesterol crystal embolization has been considered an unusual entity with poor short term prognosis. However, it is an underestimated complication according to post-mortem findings. Patients have quite characteristic risk and precipitating factors which may be an aid to suspect the diagnosis. Gastrointestinal bleeding of different severity occurs in only 10% of patients with visceral embolization. We present the case of a patient with massive lower gastrointestinal bleeding secondary to several ulcerations in the hepatic flexure due to bowel cholesterol embolization.

Aged↗
PubMed1993

[A patient with Mirizzi's syndrome. The diagnostic and therapeutic considerations].

A 35-year-old woman presented with a 4-month history of jaundice and pruritus. Endoscopic retrograde cholangiography (ERC) showed a partially obstructed common hepatic duct with a smooth and curved laterally based compression defect having the appearance of being secondary to an impacted gallbladder stone. Gallbladder filled with contrast medium but the cystic duct was not visualized, thus suggesting cholecystobiliary fistula formation. According to these radiologic findings, the diagnosis of Mirizzi syndrome was made. We discuss differential diagnosis, therapeutic aspects and the importance of preoperative diagnosis.

Adult↗
PubMed1992

[Complications and possible risk factors in endoscopic polypectomy of the colon].

We review the incidence of iatrogenic complications in a serie of 661 patients who underwent endoscopic polypectomy, performed by the same team of endoscopists and using similar technique. We discuss the role of age, sex, associated diseases, coagulation abnormalities and polyp features (size, location, shape and malignancy) in the development of complications. Five severe complications (0.75%, 3 hemorrhages and 2 perforations) were detected. Two patients required blood transfusion and two other patients surgical treatment. Recovery was successful in all patients. In eight patients (1.21%) mild complications which did not required further treatment were present. According to previously published data, these results are satisfactory. Polyp size proved to be the only risk factor with statistical significance; 23.36 +/- 14.17 mm. in complicated polypectomies vs 8.12 +/- 4.21 mm. in non-complicated cases (p less than 0.001). The remaining parameters analyzed showed no significance and therefore no predictive value.

Aged↗
PubMed1992

[Wilson's disease].

Explore the source record for details and available documents.

Hepatolenticular Degeneration↗
PubMed1991

Vertebral mineral content in diet-dependent and diet-independent hypercalciuria.

The vertebral mineral content was measured using dual photon absorptiometry in 41 calcium stone patients with idiopathic hypercalciuria. These patients had been previously divided into 2 groups (diet-dependent and diet-independent hypercalciuria) during a low sodium and low calcium diet. In some of the patients (11 with diet-dependent and 11 with diet-independent hypercalciuria) the vertebral mineral content was evaluated in relation to serum ionized calcium, intact parathyroid hormone, alkaline phosphatase and osteocalcin determined after a low sodium and low calcium diet. The vertebral mineral content, expressed as Z-VMD, was normal in diet-dependent and lower in diet-independent hypercalciuric stone patients (-0.30 +/- 1.19 versus -0.26 +/- 1.18, p less than 0.02). In 7 of 21 patients (33.3%) the vertebral mineral content was less than 2 standard deviations of the normal value, indicating a true involvement in bone metabolism. Serum intact parathyroid hormone and osteocalcin levels were not different from the controls in both groups, while alkaline phosphatase activity and ionized calcium were higher in diet-independent hypercalciuric patients. Serum ionized calcium was negatively correlated with bone vertebral density. The results suggest that an increased bone turnover may be a primary event in causing hypercalciuria in calcium stone patients unable to decrease urinary calcium to less than the calcium intake.

Absorptiometry, Photon↗
PubMed1991

Retinal cryoapplication and fibrinolysis in experimental vitreous hemorrhage.

Retinal cryoapplication accelerates blood resorption of experimental vitreous hemorrhages shortening the time until fundus visualization is possible. For the animals that underwent cryoapplication five days after blood injection into the vitreous cavity, the mean time to fundus visualization was 3.75 weeks versus 5.06 weeks for the control group (p less than 0.001). Retinal cryoapplication also causes an increase in the concentration of fibrin degradation products in the vitreous cavity, indicating an activation of fibrinolysis, one of the most important processes involved in hemorrhage resolution. Use of topical indomethacin slightly lessens the effect of cryoapplication on acceleration of blood resorption (mean 4.06 weeks until visualization), but does not influence the effect on fibrinolysis.

Administration, Topical↗