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Biomedical subjects

F Martinez

Publications and source records attributed to F Martinez.

At least 73 records · Page 4Linked to original sources
PubMed1999

Relationship between fertilization results after intracytoplasmic sperm injection, and intrafollicular steroid, pituitary hormone and cytokine concentrations.

Previous studies relating hormone and cytokine concentrations in follicular fluid to oocyte fertilizability were flawed by the uncertainty about the actual oocyte maturity status at the time of recovery and by the possible contribution of the male factor to failures of conventional in-vitro fertilization. This is the first study in which oocyte maturity was assessed immediately after recovery and only mature oocytes were selected for treatment by intracytoplasmic sperm injection. Fertilization outcomes were related to follicular fluid concentrations of 17beta-oestradiol, progesterone, follicle stimulating hormone, luteinizing hormone (LH), growth hormone (GH), prolactin (PRL), interleukin-1 (IL-1) and tumour necrosis factor-alpha (TNF alpha). Those oocytes that subsequently showed normal fertilization were harvested from follicles with higher concentrations of progesterone, GH, PRL, IL-1 and TNF alpha as compared with those of oocytes that failed to fertilize. Among the normally fertilized oocytes, low GH concentrations were associated with the failure of cleavage and with poor morphology of cleaving embryos, whereas rapidly cleaving embryos developed from oocytes recovered from follicles with high concentrations of LH and IL-1. These data suggest important roles for GH, IL-1 and TNF alpha, and of residual LH after pituitary suppression, as positive regulators of the final phase of oocyte intrafollicular development.

Cytokines↗
PubMed1999

Serosurvey for selected disease agents in white-tailed deer from Mexico.

Serum samples from 350 white-tailed deer (Odocoileus virginianus texanus) collected in March 1994 from northeastern Mexico were tested for the prevalence of antibody activity against five infectious diseases of ruminants. The prevalence rate was 81% for bluetongue virus (BTV) of all serotypes, 72% for epizootic hemorrhagic disease virus (EHDV), 3% for Borrelia burgdorferi, 69% for Anaplasma marginale, and 0% for Brucella abortus, B. melitensis, and B. ovis. These are diseases that affect domestic ruminants, and deer may act as a reservoir of infection. In addition, if deer are translocated, they may introduce pathogens to formerly disease-free areas. The high seroprevalence of BTV and EHDV cannot be related to the presence of hemorrhagic disease in the deer in this region. This is the first report to indicate the presence of B. burgdorferi infection of deer in Mexico. Despite the high prevalence of A. marginale titers, it is uncertain that deer play a role in the epizootiology of cattle anaplasmosis in the region. Apparently, white-tailed deer are unimportant in the epizootiology of brucellosis of both cattle and goats in northeastern Mexico.

Anaplasma↗
PubMed1998

Effect of mare's age and recovery methods on the recovery rate of equine follicular oocytes for IVM procedures.

Mares (n = 39) were classified according to age as young (less than 1.5 yr, n = 17) or old (more than 1.5 yr, n = 22) and sacrificed. Ovaries were measured and weighed, and the number of follicles and CL were counted. Follicle size and distribution were recorded (external: > 20 mm, < 20 mm; internal: > 5 mm, < 5 mm). External follicles were aspirated while internal follicles were sliced. The number and Type of oocytes recovered using each method were recorded. Oocyte recovery rates (oocytes/ovary) resulted in a mean of 0.92 oocytes by aspiration and 1.36 oocytes by additional slicing. The mean numbers of available follicles (8.11 and 5.02) oocytes recovered (4.94 and 3.02) and oocytes selected per ovary (3.29 and 2.32) were not significantly different in the young or old mares, respectively.

Animals↗
PubMed1998

TQI in the Albuquerque Veterans Affairs Medical Center's long-term oxygen therapy program.

BACKGROUND: Long-term oxygen therapy (LTOT) is the only treatment demonstrated to prolong the life of patients with chronic obstructive pulmonary disease. In November 1994, a multidisciplinary total quality improvement (TQI) team composed of the involved hospital services was established to reorganize and improve the LTOT program at the Albuquerque Veterans Affairs Medical Center (AVAMC), Albuquerque. FROM THE OLD TO THE NEW PROCESS: The LTOT team used a process map to analyze the current process and gather information from patients and staff regarding their satisfaction with the program. It then began working on the identified problems and streamlining the LTOT referral process. A respiratory therapy position with the specific responsibility of serving as the home oxygen (O2) coordinator (HOC) was established and filled. The evaluation process was to be initiated by the AVAMC physicians, following which the HOC would perform a newly standardized evaluation that would establish the patient's need for O2 and result in a specific prescription. RESULTS: Quality indicators were selected to monitor changes in the program. Data from chart reviews, the Veterans Affairs National Cost Containment Center, and patient surveys were used to evaluate the indicators. Timeliness of referral to the program before inpatient discharge improved, O2 prescriptions in the new program more frequently addressed activity, and the cost per patient was reduced by 37.1%. Patient satisfaction rates also improved. DISCUSSION: A motivated team with representatives of the services involved was able to analyze and dramatically improve an important but complicated program.

Cost Control↗
PubMed1998

Early glomerular dysfunction in patients with sickle cell anemia.

The purpose of this study was to analyze the determinants of glomerular filtration in nonnephrotic young adult patients with sickle cell anemia (SCA). We prospectively screened 14 patients with homozygous SCA who had normal plasma creatinine concentrations and normal or moderately elevated albuminuria (< 1 g/d). Inulin, paraaminohippuric acid, and dextran clearances were evaluated and compared with values obtained from a control group (age-matched healthy volunteers). SCA patients had a significantly higher glomerular filtration rate and effective renal plasma flow than controls (146 +/- 9 mL/min/1.73 m2 v 120 +/- 3 mL/min/1.73 m2 [P < 0.01] and 1,052 +/- 69 mL/min/1.73 m2 v 709 +/- 38 mL/min/1.73 m2 [P < 0.001], respectively). We found no correlation between glomerular filtration rate or effective renal plasma flow and hematocrit. Fractional clearance of neutral dextran was significantly elevated in SCA patients for all radii between 3.4 and 5.4 nm. Theoretical analysis of dextran transport through a heteroporous membrane model revealed a slight increase in the mean radius (ro) of restrictive pores (5.68 nm v5.50 nm; P < .001) and no significant difference in shunt pathway (omega o) values. Among the other hemodynamic parameters, the most significant change was a dramatic increase in ultrafiltration coefficient (41.3 +/- 3.6 mL/mm Hg/min/1.73 m2 v 25.1 +/- 2.6 mL/mm Hg/min/1.73 m2; P < 0.001). Our results suggest that hyperfiltration in SCA patients is associated not only with enhanced renal perfusion but also with an alteration in glomerular permeability and with an increase in Kf. This change in Kf is fully in agreement with the large increase in glomerular area previously described in SCA patients. Based on our results and those of previous morphologic studies, we propose that enhanced transglomerular trafficking of macromolecules associated with podocyte stretch lesions (defects) induced by glomerular hypertrophy may play a role in the genesis of this particular form of focal segmental glomerulosclerosis, which is associated with SCA.

Adult↗
PubMed1998

Acute renal effects of AT1-receptor blockade after exogenous angiotensin II infusion in healthy subjects.

In 10 healthy normotensive volunteers on a normal sodium diet, we evaluated the renal effects of a single oral dose of 50 mg of irbesartan (SR 47436, BMS 186295), an angiotensin II AT1-receptor antagonist, in baseline conditions and during an exogenous angiotensin II infusion (2.5 ng/kg/min). We used a double-blind, placebo-controlled, crossover design. Hormones, blood pressure, renal hemodynamics, and urinary electrolytes were measured during each phase. To examine further the determinants of glomerular filtration at the microcirculation level, fractional clearance of neutral dextran was performed, and sieving curves were applied on a hydrodynamic model of ultrafiltration. Irbesartan administration was followed by an increase in active renin and plasma angiotensin II concentrations and renal plasma flow without change of systemic blood pressure, glomerular filtration rate, or plasma aldosterone concentration. Irbesartan did not affect either sieving curves or glomerular ultrafiltration determinants. Angiotensin II infusion at 2.5 ng/kg/min elicited a slight pressor response accompanied by a decrease in glomerular filtration rate and renal plasma flow and an enhancement of fractional dextran clearance over the radius range explored (3.4-5.4 nm). The transcapillary glomerular pressure gradient deltaP and the ultrafiltration coefficient kf were computed to increase by 9% and to decrease by 23%, respectively, without change in intrinsic membrane properties. Pretreatment with irbesartan prevented all these effects of angiotensin II.

Adult↗
PubMed1998

HIV-associated nephropathy: outcome and prognosis factors. Groupe d' Etudes Néphrologiques d'Ile de France.

Records of 102 patients with biopsy-proven HIV-associated nephropathy (HIVAN) admitted to 18 hospitals in the Paris area from 1984 through 1996 were retrospectively reviewed. Demographics and clinical and laboratory features of the cohort were determined, and prognostic factors of renal and patient survival were analyzed. Renal and patient survival curves were estimated with the actuarial method. Prognostic factors were assessed by uni- and multidimensional analyses based on Cox regression models. Values were expressed as median with interquartile. The total population (median age 34) included 97% blacks and 71.5% males. Median patient follow-up was 165 d (range, 43 to 493). At the time of renal biopsy, median values of serum creatinine, proteinuria, and CD4+ cell count were 496 micromol/L, 6.5 g/24 h, and 48.5 cells/mm3, respectively. Fifteen patients were given steroids after the onset of HIVAN. Overall patient survival at 0.5, 1, and 3 yr was 73 +/- 5, 55 +/- 6, and 38 +/- 7%, respectively. The proportion of patients free of dialysis at 0.5, 1, and 3 yr was 73 +/- 5, 60 +/- 7, and 18 +/- 10%, respectively. Predictors of poor patient prognosis were a low CD4+ cell count (relative risk [RR; per 50 cells/mm3 decrease] 1.35; confidence interval [CI], 1.13 to 1.6) and antiretroviral therapy before the onset of HIVAN (RR 1.9; CI, 1.05 to 3.6). Main independent factors associated with better renal outcome were: steroid therapy (RR 0.29; CI, 0.1 to 0.9); low proteinuria level (RR [per 50% decrease] 0.7; CI, 0.5 to 0.98); low serum creatinine (RR [per 1.1 mg/dl decrease] 0.78; CI, 0.7 to 0.87); and hemoglobin level (RR [per g/dl increase] 0.76; CI, 0.58 to 1.00). HIVAN is not a rare nephropathy in Paris and its suburbs. Renal prognosis and patient survival are better than what was reported previously. Steroids may delay the downward course of HIVAN. It is not certain that in the new era of HIV therapy, the possible renal benefits of corticosteroids outweigh their potential risks. The only reliable predictor of patient survival is the intensity of immunodeficiency.

Adrenal Cortex Hormones↗
PubMed1997

[Microsurgical testicular denervation as therapy option in chronic testalgia].

Chronic testicular pain represents a challenging urological chronic pain syndrome in terms of adequate diagnosis and therapy. Reported success rates of 55-73% and 10-40% of conservative and surgical interventions are extremely low. We report on microsurgical testicular denervation as therapeutic option in patients with chronic testicular pain (CTP). 12 consecutive patients with CTP were included in our study. After complete diagnostic workup and positive response to testicular nerve blockade, all patients underwent surgery: the cremasteric muscle was dissected by electrocautery, the periadventitial layer of the testicular artery was dissected over a length of 2-3 cm. After a median follow-up of 20.6 months (4-62) 11/12 patients (92%) are pain free. None of the patients suffered from intraa- or postoperative complications. Based on our experience microsurgical testicular denervation should be performed in patients with CTP and no underlying organic disease. However, the high success rate of our surgical procedure can only be maintained if the selection of suitable patients is performed very carefully and a specific organic origin of CTP has been excluded prior to surgery.

Adult↗
PubMed1997

Lymphokine-activated killer (LAK) cell generation from peripheral blood stem cells by in vitro incubation with low-dose interleukin-2 plus granulocyte-macrophage colony-stimulating factor.

Previous reports have demonstrated granulocyte-macrophage colony-stimulating factor (GM-CSF)-mediated enhancement of lymphokine activated killer (LAK) cell function. Based on these studies we have developed a model of LAK cell generation from peripheral blood stem cells (PBSC) from cancer patients by in vitro incubation with low-dose interleukin-2 (IL-2) + GM-CSF. PBSC from seven patients were incubated for 48 h at 37 degrees C in serum-free culture medium supplemented with IL-2 at increasing concentrations (10, 100 or 1000 IU/ml) in the presence or absence of 10 IU/ml GM-CSF. LAK activity generated in cultures with 10 IU/ml IL-2 + GM-CSF was significantly higher than that generated by 10 IU/ml IL-2 and did not differ from LAK generation at optimal concentrations of IL-2 (100 and 1000 IU/ml). PBSC from five additional patients were incubated with low-dose IL-2 + GM-CSF after sequential depletion of the CD4+ and CD8+ T cell subsets. LAK activity was significantly reduced by depletion of both CD4+ and CD8+ T cells and almost completely abolished after depletion of both subsets, suggesting that T cells and not NK cells are the main LAK precursors in this model. Six patients have received two courses of LAK cells generated in vitro by low-dose IL-2 + GM-CSF on day +1 and +8 after PBSC transplant in combination with GM-CSF and IL-2 administration in vivo. The mean LAK activity in peripheral blood of these patients dramatically increased immediately after transplant from a mean of 10% to 43.2% on day +2 and remained increased during the period studied. These results are encouraging and suggest that the administration of in vitro generated LAK cells early after transplant may have a role in the control of minimal residual disease.

Adolescent↗