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J A Lorente

Publications and source records attributed to J A Lorente.

At least 19 recordsLinked to original sources

A longer duration of neo-adjuvant combined androgen blockade prior to radical prostatectomy may lead to lower tumour volume of localised prostate cancer.

OBJECTIVES: To analyse tumour volume (TV) in clinically localised prostate cancer patients treated with neo-adjuvant combined androgen blockade (CAB) therapy prior to radical prostatectomy. PATIENTS AND METHODS: Two hundred consecutive patients treated between 1996 and 2000 were retrospectively analysed. Fifty patients underwent radical prostatectomy alone and 45 were treated with CAB for 1-3 months, 83 for 4-6 months and 22 for more than 6 months before surgery. Logistic regression analysis was performed to identify the strongest independent prognosticator of organ-confined disease. RESULTS: No evidence of residual cancer was found in 11 specimens (5.6%). Regarding TV, 20 specimens showed less than 0.1cc, 33 between 0.1 and 0.49cc and 86 more than 0.5cc. Smaller TV was found in CAB-treated patients. Significant correlation was observed between treatment duration and TV. In logistic regression analysis, only CAB duration and TV were significantly correlated with organ-confined disease. CONCLUSIONS: Prominent regressive features and lower TV were found after neo-adjuvant CAB. It seems that more prolonged treatment may lead to greater tumoural regression. Only tumour burden and length of CAB therapy were independent variables significantly correlated with pathologically localised prostate cancer.

Androgen Antagonists↗

Social benefits of non-criminal genetic databases: missing persons and human remains identification.

A Missing Persons Genetic Identification Program (Phoenix Program) was implemented in Spain in order to try to identify cadavers and human remains that could not be identified using traditional forensic approaches; to our knowledge, this is the first database ever implemented and in function in the world. Two separate mitochondrial DNA (mtDNA) databases have been generated and comparisons can be made automatically to match identical or similar sequences contained in both databases. One database is called the Reference Database (RD), which contains mtDNA sequences from maternal relatives of missing persons that provide the samples voluntarily after informed consent. The other database is called the Questioned Database (QD) and is comprised of mtDNA data on unknown remains and cadavers that could not be unequivocally identified. The combined database is a civil database designed solely for human identification and because of the informed consent and voluntary donation of reference samples is different from other databases now used to solve criminal cases. It is timely and incumbent on other willing countries to begin an international collaboration so compatibility and full utility can be enjoyed with this kind of non-criminal database.

Cadaver↗

Identification of missing persons: the Spanish "Phoenix" program.

In 1999, Spain was the first country to officially start a National Program to try to identify cadavers and human remains which could not be identified by the use of traditional forensic approaches. This attempt is called "Phoenix Program". Two independent mitochondrial DNA (mtDNA) databases were generated, which can automatically compare and match identical or similar sequences. One is the Reference Database, with mtDNA sequences from maternal relatives of missing persons, who provide the samples (buccal swabs) voluntarily; the other is the Questioned Database, comprised of mtDNA data of unknown remains and cadavers. Although the first phase of the program (typing of all unidentified human remains) will probably not be completed until December 2003, positive identifications are being made in the interim. To date, more than 1,200 families have contacted Phoenix, and at least 280 reference samples and 48 questioned evidences have been analyzed. When mtDNA matches are found, another independent analysis is performed as a part of the quality control mechanism. Once a match is confirmed (so far in 6 cases), an attempt is made to analyze short tandem repeat (STR) loci. We call for international collaboration to make this effort valuable worldwide.

Cadaver↗

Hemodynamic, biochemical and morphological changes induced by aminoguanidine in normal and septic sheep.

OBJECTIVE: To define the acute hemodynamic, metabolic, and morphological changes induced by aminoguanidine, a selective iNOS inhibitor, in septic sheep. DESIGN: Prospective, nonrandomized animal study. SETTING: Animal research facility in a University Hospital. INTERVENTIONS: Adult sheep, sedated and mechanically ventilated, were monitored with a pulmonary arterial catheter and an ultrasonic blood flow probe in the mesenteric artery, to measure the systemic (Q(TOT)I) and the mesenteric (Q(MES)I) blood flow indices, and an ileal tonometer. Four groups of sheep were studied: nonseptic, septic, nonseptic treated with aminoguanidine, and septic treated with aminoguanidine (100 mg kg(-1) h(-1)) (n = 6 for each group). Sepsis was induced by the intravenous administration of E. coli. Hemodynamic and biochemical parameters were measured during 300 min. Histological changes in the liver and small intestinal mucosa were analyzed at the end of the experiment. MEASUREMENTS AND MAIN RESULTS: In nonseptic animals, aminoguanidine slightly increased mean systemic arterial pressure (MAP), decreased Q(TOT)I, and increased vascular resistance index (SVRI) and pulmonary vascular resistance index. Q(MEs)I did not change and Q(MES)I/Q(ToT)I increased. Aminoguanidine also induced intestinal intramucosal hypercarbia, hyperlactatemia, acidemia, hypoglycemia, and morphological signs indicative of tissue ischemia in the small intestinal mucosa. In septic sheep, aminoguanidine increased SVRI and MAP only at 4 h after the septic challenge and thereafter, and worsened gas exchange. CONCLUSIONS: In this model, exogenous administration of aminoguanidine induces beneficial hemodynamic effects 4 h after the septic challenge. In normal animals, however, aminoguanidine was associated with hypoglycemia, acidosis, hyperlactatemia, and intestinal mucosal ischemia.

Acidosis↗

Lectinhistochemical and cytometrical evaluation of the corpus luteum of the rat at the end of pregnancy.

Most studies on the biochemistry and structure of the corpus luteum have focused on elucidating the processes of progesterone synthesis and release. In the present work, the histochemical composition of the corpus luteum of the rat was evaluated using lectinhistochemistry on rats at the end of pregnancy (days 18-23). We also analysed the morphology of the luteal cells, to characterize the changes attributable to regression in this organ. Seven biotinylated lectins were used (CON-A, WGA, DBA, SBA, PNA, RCA and UEA-I) following pre-set protocols (ABC method). The average diameter and area of the cells and their nuclei were measured. High reactivity of the luteal cells was observed with CON-A and a lower reactivity with WGA. The capillary endothelium gave positive reactivity with WGA and to a certain extent with SBA, PNA and RCA. Vesicular structures were intensely stained with DBA, and were more abundant in sections from animals with more advanced pregnancy, which could be attributable to cellular debris, on the basis of their morphologic characteristics. There were no significant differences among the cytometric variables analysed in comparisons of the values corresponding to the different days of gestation. These observations, together with previous research, suggest that, on the day of delivery, the corpus luteum of the rat is in the very early stages of structural regression, with no changes at the morphological level, but with changes at the molecular level.

Animals↗

Systemic hemodynamics, gastric intramucosal PCO2 changes, and outcome in critically ill burn patients.

OBJECTIVES: To define the hemodynamic and gastric intramucosal PCO2 (PiCO2) changes during the first 48 hrs after burn trauma and to analyze their relationship with outcome. DESIGN: Prospective, observational study in a cohort of consecutively admitted critically ill burn patients. SETTING: Intensive care burn unit in a university hospital. PATIENTS: Forty-two patients with burns covering >20% of body surface area or inhalation injury. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients were monitored with an oximetric pulmonary arterial catheter and a gastric tonometer to measure PiCO2. The difference between arterial and gastric mucosal PCO2 (P[i-a]CO2) was considered indicative of gastric mucosal hypoxia. Hemodynamic and PiCO2 measurements were performed during the first 48 hrs after admission. Patients suffered burns covering 36.1% +/- 14.3% (mean +/- SD) and 45.3% +/- 21.9% of body surface area (survivors and nonsurvivors, respectively). All patients were successfully resuscitated by conventional standards. Nonsurvivors (n = 16) died a median of 17 days after admission. In univariate analysis, the presence of shock during the resuscitation phase, age, mixed venous pH, P[i-a]CO2, right atrial pressure, pulmonary arterial pressure, pulmonary arterial occlusion pressure, cardiac index, systemic and pulmonary vascular resistance, left ventricular stroke work index, mixed venous oxygen saturation, and systemic oxygen delivery, consumption, and extraction ratio, measured over the first 12 hrs after admission, were significantly (p < .05) different between survivors and nonsurvivors. These differences disappeared after 12 hrs after admission. Multivariate analysis identified age, percentage body surface area burned, and oxygen delivery index (6 hrs after admission) as factors independently associated with a poor outcome. P[i-a]CO2 (12 hrs after admission) was significantly greater in patients with than in those without inhalation injury (17 +/- 13 torr [2.26 +/- 1.73 kPa] vs. 6 +/- 10 torr [0.79 +/- 1.33 kPa]; p = .005). Patients with a P[i-a]CO2 difference (6 hrs after admission) > or =10 torr (1.33 kPa) had a mortality rate of 56% vs. 25% of those patients with <10 torr (p = .044). CONCLUSIONS: Our data indicate that there are hemodynamic and biochemical changes that occur early after burn trauma that are associated with prognosis after an apparently successful resuscitation. Particularly, a hemodynamic profile characterized by systemic acidosis, low systemic blood flow, and systemic and pulmonary vasoconstriction early after trauma is associated with a poor outcome. Additionally, intestinal mucosal acidosis occurs after burn trauma, is influenced by inhalation injury, and is a variable related to outcome.

Adolescent↗

Treatment of toxic epidermal necrolysis with cyclosporin A.

BACKGROUND: Toxic epidermal necrolysis (TEN) is a severe skin disorder characterized by separation of the dermal-epidermal junction, as is observed in second-degree superficial burns. It has been proposed that immunosuppressive treatment may improve prognosis of patients with TEN. METHODS: We report here a case series of patients with TEN treated with cyclosporin A (CSA) without other concomitant immunosuppressive agent. These patients (n = 11) were consecutively admitted to our Intensive Care Burn Unit because of severe TEN, involving a large body surface area (83 +/- 17% [mean +/- SD], median, 90%; range, 35-96%) and were treated with CSA 3 mg/kg per day enterally every 12 hours. We compared the series of patients treated with CSA with a historical series of patients admitted to our Intensive Care Burn Unit before CSA was introduced as part of the treatment protocol These patients (n = 6) were treated with cyclophosphamide (150 mg i.v. every 12 hours) and different doses of corticosteroids (> or =1 mg/kg per day of 6-methyl-prednisolone). Both groups of patients were similar in regard to age, delay from onset of disease to Intensive Care Burn Unit admission, and body surface area involved. RESULTS: Time from the onset of skin signs to arrest of the disease progression (1.4 +/- 0.3 days, vs. 3.6 +/- 1.5 days) and to complete reepithelialization (12.0 +/- 3.6 days, vs. 17.6 +/- 3.1 days) was significantly shorter in patients treated with CSA compared with those treated with cyclophosphamide and corticosteroids (p = 0.0002, and p = 0.0058, respectively). Significantly fewer patients in the CSA group had > or =4 organs failing (2 of 11 vs. 3 of 6, respectively, p = 0.029), had severe leukopenia (<1,000 cells/microL) (0 of 11 vs. 4 of 6, respectively, p = 0.006), or died (3 of 6 vs. 0 of 11, respectively, p = 0.0029). CONCLUSION: We conclude that immunosuppressive treatment with CSA is safe and is associated with a rapid reepithelialization rate and a low mortality rate in patients with severe TEN. Our data suggest that this regimen could be more effective than treatment with cyclophosphamide and corticosteroids. Prospective controlled trials are required to test the hypothesis that CSA is more effective than cyclophosphamide or other immunosuppressive regimens for the treatment of TEN.

Adult↗