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A de la Torre

Publications and source records attributed to A de la Torre.

At least 19 recordsLinked to original sources
PubMed2004

[Speech understanding in post-lingual adults with cochlear implants].

It is well recognised that multi-channel cochlear implants are highly effective in gaining or regaining auditory perceptual skills of severe to profound hearing-impaired people. Research shows that adults rapidly improve in speech understanding after cochlear implantation. This study reports on speech understanding from two Spanish Clinics. 32 post-lingually deafened adults were fitted with either a MED-EL COMBI 40 or COMBI 40+ cochlear implant at the Hospital Universitario San Cecilio, at the Granada or Hospital Universitario La Fe, Valencia Clinic, Spain. Subjects were assessed at 1, 3, 6 and 12 months post-fitting on a number of speech perception tests. Results showed a highly significant improvement on all speech perception tests over the time. These ratify other studies in saying that cochlear implantation is a viable and successful treatment in post-lingually deafened adults.

Adult↗
PubMed2002

Treatment of conjunctival lymphomas by beta-ray brachytherapy using a strontium-90-yttrium-90 applicator.

We reviewed the outcome of the 10 patients (13 eyes) with localized, biopsy-proven, low-grade lymphoma of the conjunctiva treated at our Department between 1988 and 1997. All patients were treated by beta-ray brachytherapy using a bidirectional 90Sr-90Y ophthalmic applicator (Applicator SIA 2, Amersham plc). Total doses, prescribed at the surface of the applicator, varied between 40 Gy and 80 Gy. With a median follow-up of 78 months (range: 14 to 146 months), seven patients remained with no evidence of relapse (67.5% 10 year disease free survival). Local control was achieved in 10 out of 13 eyes (76.9%). Two of the three local relapses were marginal. One of these three patients also developed a metachronous lymphoma in the contralateral conjunctiva. These three patients underwent a second course of brachytherapy with 90Sr/90Y and remained free of second relapse 109, 68 and 33 months after salvage therapy. No cases of systemic relapse were observed. Late (LENT-SOMA) complications were of grade 2 in five eyes, of grade 3 in one eye and of grade 4 in one eye. Late complications of grade 2 or higher were observed in one out of five patients (20%) treated with doses lower or equal to 50 Gy and in six out of eight patients (75%) treated with doses higher than 50 Gy (P=0.086). Our data indicates that beta-ray brachytherapy was ultimately able to control most conjunctival lymphomas but carried a risk of late complications and marginal relapses that was possibly higher than the rates reported for other radiotherapy techniques.

Adult↗
PubMed2001

Effect of total body irradiation on peri-implant tissue reaction: an experimental study.

The aim of the present study was to evaluate the osseointegration process under total body irradiation conditions (LD 50/30). Twenty Wistar rats (mean body weight: 90 g) were used. Under ethyl urethane intraperitoneal anesthesia (1 g/kg body weight), the animals were irradiated with a single 700 cGy dose (linear accelerator 6 Mev photons). Four days post irradiation, a titanium laminar implant was placed in the left tibia of each rat. Antibiotic therapy (ceftriaxone) was administered daily post implantation, to prevent infection by radiation. Fourteen days post implantation, the animals were killed by ether overdose. The tibiae were resected, radiographed and processed for embedding in methyl methacrylate. The results showed impaired osteogenesis and absence of osseointegration in experimental tibiae. This could be due to a direct action of total body irradiation on osteogenesis precursor cells. This effect would impair bone formation involved in peri-implant osseointegration processes in this experimental model.

Animals↗
PubMed2000

The use of alternative systems for the ecotoxicological screening of complex mixtures on fish populations.

This paper presents the results of the use of alternative systems in a screening study of four complex mixtures. The following tests were performed: in vitro induction of micronuclei in a rainbow trout-derived cell line by flow cytometry, and hatching percentage, time of hatching and teratogenic alterations on the embryolarval development on medaka fish eggs. The results obtained with the proposed tests in this study allows an increase in the information level in a short period of time (2 weeks), using very low sample volumes (< 100 ml). Inclusion of chronic and specific effects (genotoxicity and teratogenicity) allows the selection of the most sensitive endpoint to increase security factors in the ecotoxicological assessment of complex mixtures, so that detailed studies can be focused only on those samples which require further research.

Animals↗
PubMed1999

Phase II study of radiochemotherapy with UFT and low-dose oral leucovorin in patients with unresectable rectal cancer.

PURPOSE: To determine the activity and evaluate the toxicity of uracil and tegafur in a 4:1 molar concentration (UFT) plus low-dose leucovorin administered concomitantly with pelvic irradiation in patients with unresectable or recurrent rectal cancer. METHODS AND MATERIALS: Thirty-five patients (22 with primary unresectable tumors and 13 with locally recurrent tumors) were enrolled in the trial. Thirty-five patients were evaluable for toxicity and 32 of these were evaluable for clinical response. Patients received 300 mg/m2/day UFT and 30 mg/day leucovorin on days 8-35 concomitantly with pelvic radiotherapy, to a total dose of 45 Gy. RESULTS: Eight of the 35 (23%) patients developed Grade 3 diarrhea and were treated with radiotherapy alone after this event. Of the 22 patients with unresectable primary tumors, 17 underwent surgery, and resection was feasible in 15 cases (88%). Of the 32 patients evaluable for clinical response, 4 (13%) had a complete clinical response (CR) and 22 (69%) a partial response (PR). A complete pathologic response was observed in 3 cases (18%) and, a PR in 11 cases (65%). CONCLUSION: The response rates achieved with this schedule seem comparable to those obtained with 5-FU and radiotherapy. These results warrant further evaluation of this combination in patients with unresectable or locally advanced tumors.

Adult↗
PubMed1999

Effect of age on vanadium nephrotoxicity in rats.

The present study was designed to assess potential age dependent differences of vanadium nephrotoxicity in the rat following parenteral administration of vanadate. Young (22 days) and adult (62 days) male Sprague-Dawley rats received i.p. injections of sodium orthovanadate at 10 mg/kg/day for 8 consecutive days. Two additional groups of control rats received i.p. injections of 0.9% saline during the same period. Significant age-differences were found in most of the parameters used as indicators of nephrotoxicity in young and adult rats, with adverse renal effects being more severe with age. Vanadium-induced morphologic changes in the kidney were also more pronounced with age. These findings agree with a higher renal concentration of vanadium in the group of adult rats treated with vanadate than in the vanadate-untreated group. The current results can be of concern if in the future, vanadium compounds can be administered in the treatment of diabetic patients.

Aging↗
PubMed1998

Comparison of the effectiveness of 2,3-dimercaptopropanol (BAL) and meso-2,3-dimercaptosuccinic acid (DMSA) as protective agents against mercuric chloride-induced nephrotoxicity in rats.

The effectiveness of 2,3-dimercaptopropanol (BAL) and meso-2,3-dimercaptosuccinic acid (DMSA) on HgCl2-induced nephrotoxicity was studied in the rat. Seven groups of adult male rats were given a single sc toxic dose of HgCl2 (0.68 mg/kg) followed by 0.9% saline (positive control group), BAL (15, 30, and 60 mg/kg) or DMSA (50, 100, and 200 mg/kg) administered ip at 0, 24, 48, and 72 h thereafter. Although the renal function of HgCl2-exposed rats was slightly improved after BAL administration, Hg concentrations in the kidney were only reduced at 60 mg/kg. In addition, the protective effect of BAL was not dose-related. In contrast to BAL, DMSA was effective in increasing the urinary excretion of Hg and in reducing the renal Hg content. These results show that DMSA would be more effective than BAL in preventing or in protecting against inorganic Hg-induced nephrotoxicity.

Animals↗
PubMed1998

Apoptosis and hepatic allograft reperfusion injury.

Necrosis and apoptosis are distinct, but nonexclusive mechanisms of cell death. Until recently, investigators have focused upon necrosis as the sine qua non of lethal cell injury. Specifically, within the realm of liver transplantation, preservation strategies dealing with ischemia/reperfusion injury have concentrated upon minimizing the biochemical and histologic correlates associated with necrosis. Little is known of the role of apoptosis in reperfusion injury in human liver transplantation. Post-reperfusion liver biopsies from 35 patients were retrospectively analyzed for histologic evidence of necrosis. Apoptosis was identified histologically and using a chromogenic technique of in situ labeling of fragmented DNA. The number of apoptotic cells increased in parallel with the necrosis reperfusion score in a significant fashion (p = 0.003 by ANOVA). There was not a Zone 1, 2 or 3 predominance to the histologic distribution of apoptotic cells. The recipient peak serum transaminase values were also noted to increase with the reperfusion score (p = 0.001 by ANOVA). These results suggest that: 1) apoptosis occurs in the setting of reperfusion injury during human orthotopic liver transplantation (OLT); and 2) the extent of apoptosis increases in parallel with pathologic and biochemical parameters of reperfusion injury. Given the distinct nature of apoptosis and the highly regulated and conserved pathway for its initiation, inhibition of apoptosis with specific molecular targets, may serve to decrease allograft reperfusion injury.

Adult↗
PubMed1997

Comparative effects of the chelators sodium 4,5-dihydroxybenzene-1,3-disulfonate (Tiron) and diethylenetriaminepentaacetic acid (DTPA) on acute uranium nephrotoxicity in rats.

Sodium 4,5-dihydroxybenzene-1,3-disulfonate (Tiron) and diethylenetriaminepentaacetic acid (DTPA) are two chelating agents that have been demonstrated to be effective in the treatment of experimental poisoning by a number of heavy metals. In this study, the effects of Tiron and DTPA on uranium-induced nephrotoxicity were evaluated in a rat model. A series of four Tiron or DTPA injections was administered intraperitoneally to adult male Sprague-Dawley rats immediately after a single subcutaneous injection of uranyl acetate dihydrate (5 mg/kg) and at 24, 48 and 72 h thereafter. Positive and negative control groups received 0.9% saline with or without uranyl acetate, respectively. Tiron effectiveness was assessed at 400, 800 and 1600 mg/kg, whereas DTPA was administered at 250, 500 and 1000 mg/kg. Although the urinary excretion of uranium was significantly enhanced by Tiron administration, significant amounts of uranium still remained in the kidney at the end of the treatment. However, the partial reduction of the renal uranium concentrations was in accordance with the amelioration noted in some urinary and serum indicators of uranium nephrotoxicity. Moreover, Tiron administration also reduced the severity of the uranium-induced histological alterations in the kidney. According to these results, Tiron offers only a modest encouragement with regard to its possible therapeutic potential to treat acute uranium-induced nephrotoxic effects. In turn, DTPA was less effective than Tiron in protecting against the nephrotoxicity of uranium in rats.

1,2-Dihydroxybenzene-3,5-Disulfonic Acid Disodium ↗
PubMed1996

Treatment of non-Hodgkin's lymphoma of Waldeyer's ring: radiotherapy versus chemotherapy versus combined therapy.

Treatment of stage IA non-Hodgkin's lymphoma (NHL) of Waldeyer's ring remains controversial, probably because of the small number of patients and the scarcity of controlled studies. Between 1981 and 1991, 316 patients with stage I NHL of Waldeyer's ring were randomised for treatment with radiotherapy alone (extended fields), 101 patients; combined chemotherapy with a regimen of CHOP (cyclophosphamide, vincristine, doxorubicin, and prednisone) or CHOP-like (epirubicin instead of doxorubicin), 106 patients; and combined therapy (radiotherapy followed by the same combination chemotherapy), 109 patients. Median follow-up was 6.8 years. Complete response was achieved in 93, 87 and 97%, respectively. Relapses were least frequent in patients treated with combination therapy. The 5-year rate for failure-free survival was 48% for radiation therapy, 45% for the patients who were treated with chemotherapy, which was statistically significantly less than the 83% for patients treated with combined therapy (P < 0.001). Overall survival was also better in the combined therapy arm: 90%, statistically different to 58% for the patients treated with chemotherapy alone and 56% for patients treated with radiation therapy (P < 0.001). Toxicity was mild and late side-effects were not observed in any patients. From these results combined therapy should be considered as the best therapeutic approach in patients with localised NHL of Waldeyer's ring.

Adult↗
PubMed1996

The health insurance status of US Latino women: A profile from the 1982-1984 HHANES.

OBJECTIVES: This research studied the correlates of health insurance status among three major subpopulations (Mexican, Puerto Rican, and Cuban) of adult (ages of 20 to 64) Latino women. METHODS: Data from the Hispanic Health and Nutrition Examination Survey (HHANES), 1982-1984, were examined to determine the percentages of health insurance coverage among the sample populations and to assess the relationship between access to coverage and selected sociodemographic employment/income, ancestry, and acculturation variables. RESULTS: Variations in health insurance coverage existed by Latina subpopulation. While Puerto Rican women had the highest percentage of any health insurance coverage, Mexican-origin women (particularly those 50 to 64 years old) had the lowest. For all three Latina groups, health insurance coverage was greater among those who reported a family income above the poverty level than among those whose income fell below the poverty level; employment location, acculturation variables, and ancestry were also related to coverage. CONCLUSIONS: Eligibility requirements, particularly for Mexican-and Cuban-origin women, need to be streamlined, and innovative health insurance programs need to be developed to increase access of Latinas to health insurance.

Acculturation↗
PubMed1995

Salvage brachytherapy and salvage surgery for recurrent oropharyngeal carcinoma following radiotherapy.

We reviewed 21 patients who underwent salvage treatment after a biopsy of proven locally recurrent carcinoma of the oropharynx. Two of these patients underwent a second salvage treatment after failure of the first. Treatment was performed with Ir192 interstitial implant in 17 cases (13 rT1 and 4 rT2); by surgery in five cases (3 rT1, 1 rT2, 1 rTx), including two patients who had relapsed after salvage treatment with Ir192 implant; and by hyperfractionated external beam irradiation plus concomitant Tegafur chemotherapy in one case (rT3). The primary tumour was controlled in four of the 17 cases (23 per cent) treated with Ir192 implant. Of these four patients, two remained disease-free 42 and 59 months after treatment, one died of nodal metastases eight months after treatment and another of distant metastases 19 months after treatment. Four of the five cases (80 per cent) treated with surgery, including two patients who relapsed after salvage brachytherapy, remained free from local, regional and distant relapse 21, 25, 31 and 56 months after treatment.

Brachytherapy↗
PubMed1995

Influence of boost technique (external beam radiotherapy or brachytherapy) on the outcome of patients with carcinoma of the base of the tongue.

We reviewed 90 patients with squamous cell carcinoma of the base of the tongue. Fifty-three patients were treated with external beam radiotherapy alone (3 T1, 11 T2, 21 T3, and 18 T4 tumors) and thirty-seven patients were treated with external beam radiotherapy plus brachytherapy boost (4 T1, 15 T2, 11 T3, and 7 T4 tumors). For patients with T1, T2 and T3 primaries, the actuarial 3-year local relapse-free survival was 42% following external beam radiotherapy alone and 67% following external beam radiotherapy plus brachytherapy (p < 0.05). The actuarial 3-year cause specific survival for these T-stages was 37% for patients treated with external beam radiotherapy alone and 53% for patients treated with external beam radiotherapy plus brachytherapy (p = 0.1). In the Cox multivariate analyses restricted patients with T1, T2 and T3 staged tumors, treatment modality was the only predictor for local control but no influence on specific survival was found. The trend towards significant differences in specific survival found in the univariate comparison of both treatment modalities was probably due to the significantly higher number of N-positive patients treated with external beam radiotherapy alone. When all stages were included in the Cox analysis, low hemoglobin level, invasion of deep muscle, number of palpable nodes, and history of weight loss significantly influenced the outcome. Soft tissue necrosis occurred more frequently in patients treated with external beam radiotherapy plus brachytherapy (33% vs. 10%, p = 0.52).

Adult↗
PubMed1994

Episcleral iridium-192 wire therapy for choroidal melanomas.

PURPOSE: To evaluate the effectivity of high-dose episcleral iridium-192 wires in the treatment of choroidal melanoma. METHODS AND MATERIALS: In 1983, the Departments of Radiation Oncology and Ophthalmology at the Clínica Puerta de Hierro, Madrid, Spain, initiated a clinical study using removable episcleral iridium-192 wires in the treatment of choroidal melanoma. Sixty-six evaluable patients were treated from January 1983 through July 1992. Two patients had a small sized tumor (3%), 28 had a medium sized tumor (42%), and 36 patients had a large tumor (54%). The mean follow-up was 40 months (6-118 months). The dose to the apex of the tumor ranged from 66 to 97 Gy (mean 76.6 Gy), and the doses at 2 mm depth ranged from 77 to 433 Gy (mean 200 Gy). RESULTS: Tumor regression or stabilization was observed in 53 of the 66 patients (90%). Visual acuity improved following treatment in 5 out of 54 patients (9%), remaining unchanged in 30 out of 54 (56%), and decreased in 19 out of 54 (35%) patients. The remaining seven patients had undergone enucleation. Late complications have been documented in 20 out of 66 patients (30%), including 6 patients in whom enucleation was required because of radiation-related complications. The probability of survival and survival free of local progression was 93% at 5 years and 79% at 10 years. The probability of retaining the treated eye is 82% after the fifth year posttreatment. CONCLUSIONS: Treatment of choroidal melanomas with episcleral iridium-192 wires is as effective as treatment with other radioactive applications. We feel that our results using iridium-192 wires are comparable to the other methods. However, we think that our technique is simple to implement, relatively inexpensive, and well tolerated.

Brachytherapy↗