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R Vela

Publications and source records attributed to R Vela.

17 recordsLinked to original sources
PubMed2002

Long-term follow-up of a randomized prospective trial comparing a standard 81 mg dose of intravesical bacille Calmette-Guérin with a reduced dose of 27 mg in superficial bladder cancer.

OBJECTIVES: To determine the efficacy of a three-fold reduced dose (RD, 27 mg) of intravesical bacille Calmette-Guérin (BCG) against the standard dose (81 mg) in patients with superficial bladder cancer, assessing recurrence, progression and differences in toxicity. PATIENTS AND METHODS: Five hundred patients with superficial bladder cancer (Ta, T1, Tis) were enrolled and randomly assigned to be treated after transurethral resection of all visible lesions with intravesical BCG Connaught strain (weekly x six and thereafter fortnightly x six) either with the standard or RD instillation. RESULTS: All but one of the 500 patients were evaluable for efficacy and toxicity (252 in the standard arm and 247 in the RD arm). The median follow-up was 69 months (maximum 104); 71 (28%) patients in the standard arm and 76 (31%) in the RD arm developed recurrences; the median time to recurrence has not yet been attained, but at 5 years the mean (sd) percentage of recurrence-free patients was 70.5 (3.12) and 70.4 (3.1) for the standard and RD arms, respectively. In patients presenting with multifocal tumours, the standard dose was more effective against recurrences than the RD (P=0.0151). In those with G3 and high-risk tumours overall, the superiority of the standard dose was marginal (P=0.060 and P=0.082). Twenty-nine (11.5%) tumours in the standard arm and 33 (13.3%) in the RD arm progressed to invasive disease; the median time to progression has not yet been attained, but the percentage of progression-free patients at 5 years was 88.8 (2.23) and 86.9 (2.31) for the standard and RD arms, respectively. The standard dose was more effective than the RD against progression only in patients with multifocal disease (P=0.048). Twelve (4.8%) cystectomies were performed in the standard and 15 (6.1%) in the RD arm. Currently, 106 (21.2%) patients have died, but only 38 (7.6%) from bladder cancer, i.e. 20 (7.9%) in the standard and 18 (7.5%) in RD arm. Overall the disease-specific death rate was lower for those patients who completed the scheduled treatment. The cause-specific survival at 5 years did not differ between the arms (P=0.76) but there was a trend toward better cause-specific survival for patients with multifocal tumours in the standard arm. Toxicity differed between the arms, significantly more patients having no toxicity in the RD arm, and fewer having delayed instillations or withdrawing. However, severe systemic toxicity occurred even in patients treated with the RD, in a similar proportion to those receiving the standard dose. CONCLUSION: Overall, the RD gave similar results for recurrence and progression but with significantly less toxicity. However, patients with multifocal tumours fared better with the standard dose and there was a trend towards better recurrence rates in patients with high-risk tumours. We recommend continuing to use the standard dose for high-risk tumours, while we consider the reduced dose safe and effective for intermediate-risk lesions and for maintenance schedules.

Adjuvants, Immunologic↗
PubMed2001

Left mini-thoracotomy for beating heart bypass grafting: a safe alternative to high-risk intervention for selected grafting of the circumflex artery distribution.

BACKGROUND: Progression of disease and bypass graft attrition results in a population of patients who require repeated coronary interventions. Frequently, these patients have patent internal mammary artery grafts and require isolated intervention to the circumflex distribution. As an alternative to high-risk repeated sternotomy and conventional bypass surgery or catheter-based intervention, the circumflex marginal vessels may be approached by thoracotomy. We reviewed our experience in revascularizing the circumflex distribution with off-pump techniques via left mini-thoracotomy. METHODS AND RESULTS: Thirty-two patients underwent off-pump bypass grafting of the circumflex vessels via thoracotomy from December 1995 to April 2000. Twenty-seven patients presented with circumflex disease after having previous bypass grafting. Five patients, who presented with circumflex disease and either nondiseased or ungraftable disease in their other arteries, were revascularized as a primary procedure. There was no observed mortality. Seven patients (22%) required inotropes on leaving the operating room, and 3 patients (9.4%) received transfusion of packed red blood cells. There was 1 reoperation for bleeding and 1 patient with a postoperative neurological deficit. There were no perioperative myocardial infarctions. The average length of stay was 4.8 days from time of surgery to discharge. CONCLUSIONS: Off-pump grafting via thoracotomy provides a safe and effective alternative approach for patients requiring limited revascularization. Potential cardiac injury and danger to viable grafts from repeated sternotomy is minimized, and manipulation of the diseased ascending aorta is avoided. Morbidity, hospital length of stay, and cost are less than for conventional repeated coronary bypass surgery.

Arteries↗
PubMed2001

Familial atypical progressive supranuclear palsy associated with homozigosity for the delN296 mutation in the tau gene.

Heterozygous missense and splice-site mutations in the tau gene have been previously identified in familial frontotemporal dementia with autosomal dominant inheritance. Here we report a Spanish kindred in which two brothers born from a third-degree consanguineous marriage were both affected with atypical progressive supranuclear palsy. A homozygous deletion at codon 296 (delN296) was identified in one of the affected siblings. Among the heterozygous carriers, two members with probable Parkinson's disease were identified, but none of heterozygotes developed atypical parkinsonism. The delN296 mutation lies in the sequence corresponding to the second tubulin-binding repeat of tau protein and affects one asparagine residue absolutely conserved in other species. This finding indicates that homozygous mutations in the tau gene may also cause hereditary tauopathies.

Adult↗
PubMed1990

Vitamin B6 status in uremia.

We have studied vitamin B6 status in 26 uremic patients, 18 on maintenance hemodialysis and 8 nonhemodialyzed. The vitamin B6 status was estimated by an assay of erythrocyte aspartate aminotransferase and coenzyme stimulation. Hemodialyzed uremic patients were found to have vitamin B6 deficiency. Patients were treated with 150 mg pyridoxine hydrochloride daily for 4 weeks. Erythrocyte aspartate aminotransferase increased significantly in both groups of uremic patients, the increase being greater in hemodialyzed patients. In vitro pyridoxal phosphate stimulation produces an erythrocyte aspartate aminotransferase activity greater than that obtained before pyridoxine hydrochloride administration. After cessation of pyridoxine hydrochloride treatment, erythrocyte aspartate aminotransferase decreases in hemodialyzed patients, while it remains elevated in nonhemodialyzed patients. The data obtained appear to indicate that vitamin B6 administration to patients with chronic renal insufficiency must be appraised not only for correcting the deficit but also for increasing the intracellular pyridoxal phosphate concentration, which could modify the possible functional impairment at the level of apoenzymes that use pyridoxal phosphate.

Adult↗
PubMed1985

Corynebacterium group D2 as a cause of alkaline-encrusted cystitis: report of four cases and characterization of the organisms.

In four patients with alkaline-encrusted cystitis, Corynebacterium group D2 was isolated from consecutive urine cultures and stones. Encrusted cystitis occurred in bladders harboring inflammatory or tumorous lesions in patients with chronic or recurrent urinary tract infections appearing after surgery or instrumentation. The urease activity of Corynebacterium group D2 and the neutralization of this enzyme by acetohydroxamic acid are shown. Clinical improvement, disappearance of struvite crystals, and decrease of the urine pH were obtained when these bacteria were eliminated from urine samples. Corynebacterium group D2 strains were highly resistant to many antimicrobial agents but were highly susceptible to norfloxacin and vancomycin when tested at two pHs (7.4 and 8.5).

Aged↗
PubMed1981

[Adrenergic receptors in sheep urethra (author's transl)].

The presence and types of adrenergic receptors in sheep urethra were investigated in vitro by pharmacological stimulation and blockage of alfa and beta receptors with agonist and antagonist drugs. Both adrenergic receptors were identified. Alfa stimulation increased tonicity and strength of contractions. Relaxation was obtained by beta adrenergic stimuli. Beta receptors in the sheep urethra belong to beta-2 type.

Adrenergic alpha-Agonists↗
PubMedDate not supplied

[Fibromuscular dysplasia with moyamoya phenomenon in a patient with Alport's syndrome. A type IV collagen disorder].

INTRODUCTION: Alport's syndrome is a hereditary progressive nephropathy associated with neurosensorial deafness, secondary to mutations of the genes which codify the a chains of collagen IV. In the literature we have found isolated reports of cases with nervous system involvement. CLINICAL CASE: A 37 year old woman was diagnosed as having Alport's syndrome with terminal secondary chronic renal failure and bilateral neurosensorial deafness. She was assessed following repeated transient ischemic attacks of the left hemisphere over the previous three years. Neurological examination was normal. Magnetic resonance showed an ischemic stroke of the left frontal white matter, and on arteriography there was tubular stenosis of the left extracranial internal carotid artery and proximal occlusion of the homolateral anterior and medial cerebral arteries with a compensatory deep vascular network, compatible with fibromuscular dysplasia and secondary moyamoya phenomenon. CONCLUSIONS: Although the association between fibromuscular dysplasia and Alport's syndrome may be casual, we suggest that there may be a common mechanism of pathogenesis in both syndromes, related to the expression of type IV collagen in the vascular basal membranes.

Adult↗