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F J Diaz

Publications and source records attributed to F J Diaz.

At least 19 recordsLinked to original sources
PubMed2006

The preantral granulosa cell to cumulus cell transition in the mouse ovary: development of competence to undergo expansion.

The transition of preantral to antral follicles is one of the major steps in follicular development, yet little is known about the molecular and functional changes that occur as preantral granulosa cells differentiate into cumulus cells. The cumulus oophorus of large antral follicles undergoes expansion in response to the preovulatory surge of gonadotropins, but preantral granulosa cells do not. The objective of this project was to determine the molecular mechanisms underlying this differential response. Cumulus expansion in vitro requires secretion of cumulus-expansion enabling factors (CEEFs) by the oocyte and stimulation by a ligand, epidermal growth factor (EGF) or follicle-stimulating hormone (FSH). This combined stimulation results in activation of MAPKs (MAPK3/1 (formerly ERK1/2) and MAPK14 (formerly p38)) and increased Has2, Ptgs2, Tnfaip6 and Ptx3 mRNA levels, all of which are required for cumulus expansion. Only fully-grown oocytes from antral follicles were competent to enable expansion and increases in expansion-related transcripts in cumulus cells, whereas growing oocytes of preantral follicles did not. To assess the competence of preantral granulosa cells to generate responses associated with expansion, they were treated with FSH or EGF and co-cultured with fully-grown oocytes secreting CEEFs. MAPKs were activated by EGF in preantral granulosa cells to essentially the same levels as in cumulus cells. Preantral granulosa cells treated with EGF, but not those treated with FSH increased Has2, Ptgs2 and Ptx3 mRNAs to 17-96% of the levels observed in cumulus cells. In contrast, the level of Tnfaip6 mRNA was minimally stimulated in preantral granulosa cells. Therefore, preantral granulosa cells do not undergo expansion for two fundamental reasons. First, the growing oocytes of preantral follicles do not secrete active CEEFs. Second, activation of MAPKs alone in preantral granulosa cells, even in the presence of CEEFs, is not sufficient to increase the expression of essential transcripts, particularly Tnfaip6 mRNA. Thus, preantral granulosa cells differ from cumulus cells in CEEF-dependent processes downstream of the activation of MAPKs.

Animals↗
PubMed2005

Risperidone half-life in a patient taking paroxetine -- a case report.

This case report further establishes the inhibitory effects of paroxetine on risperidone (R) metabolism in a patient whose R was discontinued due to side effects. Baseline through levels in ng/ml were 33 for R, 9 for 9-hydroxyrisperidone (9-OHR) and 42 for the total moiety. The fourth morning after R discontinuation, levels were 4 for R, 1 for 9-OHR and 5 for the total moiety. The estimated half-lives were 23.8 hours for R, 22.8 hours for 9-OHR and 23.5 hours for the total moiety.

Adult↗
PubMed2004

The effects of feeding fish oil on uterine secretion of PGF2alpha, milk composition, and metabolic status of periparturient Holstein cows.

The objectives were to determine the effect of dietary fish oil (FO) on uterine secretion of PGF2alpha, milk production, milk composition, and metabolic status during the periparturient period. Holstein cows were assigned randomly to diets containing FO (n = 13) or olive oil (OO, n = 13). Cows were fed prepartum and postpartum diets that provided approximately 200 g/d from 21 d before the expected parturition until 21 d after parturition. The FO used contained 36% eicosapentaenoic acid (EPA, C20:5, n-3) and 28% docosahexaenoic acid (DHA, C22:6, n-3). Blood samples were obtained from 14 d before the due date until d 21 postpartum. A total of 6 FO and 8 OO cows without periparturient disorders were used in the statistical analyses of PGF2alpha-metabolite (PGFM) and metabolite concentrations. Length of prepartum feeding with OO or FO did not differ. Proportions of individual and total n-3 fatty acids were increased in caruncular tissue and milk of cows fed FO. The combined concentrations of EPA and DHA in caruncular tissue were correlated positively with the number of days supplemented with FO. Cows fed FO had reduced concentrations of plasma PGFM during the 60 h immediately after parturition compared with cows fed OO. Concentrations of prostaglandin H synthase-2 mRNA and protein in caruncular tissue were unaffected by diet. Production of milk and FCM were similar between cows fed the two oil diets. However, cows fed FO produced less milk fat. Feeding FO reduced plasma concentrations of glucose. Dietary fatty acids given during the periparturient period can reduce the uterine secretion of PGF2alpha in lactating dairy cows and alter the fatty acid profile of milk fat.

Animals↗
PubMed2003

Dimensions of suicidal behavior according to patient reports.

Five factor analyses with limitations explored the Suicidal Intent Scale (SIS) subscales reflecting suicidal behavior dimensions. This larger sample study conducts an exploratory factor analysis of the SIS. Two large samples of suicide attempters (N= 435 and N= 252) from a general hospital were studied. The validity of SIS subscales obtained from the factor analysis was investigated by examining the association between the subscales and clinical variables. There were two factors: expected lethality and planning. In both samples, male gender and depression tended to be associated with higher scores in both subscales (small to medium effect sizes). Hospitalization was associated with higher scores in both SIS subscales (medium to large effects) suggesting that these subscales were reasonably good predictors of suicide attempt severity. Clinicians assessing patient reports to establish the severity of suicide attempts need to ask questions regarding both dimensions: expected lethality and planning.

Adult↗
PubMed2002

Regulation of progesterone and prostaglandin F2alpha production in the CL.

After the luteinizing hormone (LH) surge, the cells that remain from the ovulated follicle undergo a process of differentiation termed luteinization. Two key features of the cells after luteinization are the capacity for tremendous production of progesterone [10(16) molecules of progesterone per (min/(g of CL))] and the capacity to undergo regression or death of the cells at the appropriate time. There are two steroidogenic cell types, the small and large luteal cells that are regulated by different mechanisms. In small luteal cells, production of progesterone is stimulated by LH through the protein kinase A (PKA) pathway. The large luteal cells of ruminants produce large quantities of progesterone that is independent of LH stimulation. Although luteotrophins clearly regulate luteal function, much of luteal progesterone production in some species appears to be constitutive, consistent with the autonomous aspects of the large luteal cell. The key regulated step in luteal progesterone production appears to be regulation of transport of cholesterol to the inner mitochondrial membrane apparently mediated by the steroidogenic acute regulatory protein (StAR). In addition, our recent research indicates that PKA is tonically active in large luteal cells and this may be responsible for the high, relatively autonomous nature of luteal progesterone production. Regression of the corpus luteum (CL) in many species is initiated by prostaglandin (PG) F2alpha secreted from the uterus. Luteal cells also have the capacity for production of PGF2alpha. Luteal PGF2alpha production can be regulated by a variety of substances including inhibition by progesterone and stimulation by cytokines. We have also characterized a positive feedback pathway in ruminant and porcine CL in which small amounts of uterine PGF(2alpha) stimulate intraluteal production of PGF2alpha due to induction of the cycloxygenase-2 (Cox-2) enzyme in large luteal cells. This positive feedback pathway is only present in CL that has acquired the capacity for luteal regression ( approximately day 7 in cow, approximately day 13 in pig). Regulation by protein kinase C (PKC) of transcriptional factors interacting with an E-box in the 5' flanking region of the Cox-2 gene is the critical regulatory element involved in this positive feedback pathway. Thus, luteinization in some species appears to change specific gene transcription such that progesterone production becomes relatively independent of acute luteotrophic regulation and intraluteal PGF2alpha synthesis is induced by the second messenger pathways that are activated by PGF2alpha.

Animals↗
PubMed2000

Prostaglandin f(2alpha) induces distinct physiological responses in porcine corpora lutea after acquisition of luteolytic capacity.

This study examines differences in intracellular responses to cloprostenol, a prostaglandin (PG)F(2alpha) analog, in porcine corpora lutea (CL) before (Day 9 of estrous cycle) and after (Day 17 of pseudopregnancy) acquisition of luteolytic capacity. Pigs on Day 9 or Day 17 were treated with saline or 500 microgram cloprostenol, and CL were collected 10 h (experiment I) or 0.5 h (experiment III) after treatment. Some CL were cut into small pieces and cultured to measure progesterone and PGF(2alpha) secretion. In experiment I, progesterone remained high and PGF(2alpha) low in luteal incubations from either Day 9 or Day 17 saline-treated pigs. Cloprostenol increased PGF(2alpha) production 465% and decreased progesterone production 87% only from Day 17 luteal tissue. Cloprostenol induced prostaglandin G/H synthase (PGHS)-2 mRNA (0.5 h) and protein (10 h) in both groups. In cell culture, cloprostenol or phorbol 12, 13-didecanoate (PDD) (protein kinase C activator), induced PGHS-2 mRNA in luteal cells from both groups. However, acute cloprostenol treatment (10 min) decreased progesterone production and increased PGF(2alpha) production only from Day 17 luteal cells. Thus, PGF(2alpha) production is induced by cloprostenol in porcine CL with luteolytic capacity (Day 17) but not in CL without luteolytic capacity (Day 9). However, this change in PGF(2alpha) production is not explained by a difference in induction of PGHS-2 mRNA or protein.

Animals↗
PubMed2000

Prostaglandin E(2) increases bovine leukemia virus tax and pol mRNA levels via cyclooxygenase 2: regulation by interleukin-2, interleukin-10, and bovine leukemia virus.

Prostaglandin E(2) (PGE(2)), produced by macrophages, has important immune regulatory functions, suppressing a type 1 immune response and stimulating a type 2 immune response. Type 1 cytokines (interleukin-2 [IL-2], IL-12, and gamma interferon) increase in freshly isolated peripheral blood mononuclear cells (PBMCs) of animals with an early disease stage of bovine leukemia virus (BLV) infection, while IL-10 increases in animals with a late disease stage. Although IL-10 has an immunosuppressive role in the host immune system, IL-10 also inhibits BLV tax and pol mRNA levels in vitro. In contrast, IL-2 stimulates BLV tax and pol mRNA and p24 protein expression in cultured PBMCs. The inhibitory effect of IL-10 on BLV expression depends on soluble factors secreted by macrophages. Thus, we hypothesized that PGE(2), a cyclooxygenase 2 (COX-2) product of macrophages, may regulate BLV expression. Here, we show that the level of COX-2 mRNA was decreased in PBMCs treated with IL-10, while IL-2 enhanced the level of COX-2 mRNA. Addition of PGE(2) stimulated BLV tax and pol mRNA levels and reversed the IL-10 inhibition of BLV mRNA. In addition, the specific COX-2 inhibitor, NS-398, inhibited the amount of BLV mRNA detected. Addition of PGE(2) increased BLV tax mRNA regardless of NS-398 addition. PGE(2) inhibited antigen-specific PBMC stimulation, suggesting that stimulation of BLV tax and pol mRNA levels by PGE(2) is independent of cell proliferation. These findings suggest that macrophage-derived COX-2 products, such as PGE(2), regulate virus expression and disease progression in BLV infection.

Animals↗
PubMed1997

Epithelioid hemangiomas of the maxillofacial area. A report of three cases and a review of the literature.

Epithelioid hemangioma, also named angiolymphoid hyperplasia with eosinophilia, is a very rare tumor that arises from vascular structures. The relative incidence in the skin of the head and neck area is rather high as compared to other parts of the body. Three cases are reported in an atypical location and the differential diagnosis with other similar vascular lesions and their pathologic features is presented.

Adult↗
PubMed1992

Sarcomas of the head and neck.

Fourteen cases of sarcomas involving the head and neck over a period of 15 years were reviewed. The male to female ratio was 3.5:1. Mean age of occurrence was 33.4 years, with a range of 5-84 years. Soft tissue was the site of origin in three cases, maxilla in four and mandible in seven patients. Radical surgery with resection of adequate disease-free margins was the most effective mode of treatment. Radiotherapy and chemotherapy was used in selected cases. Recurrence occurred in 42.9% of patients, and was the main cause of death. Three patients (21.4%) developed distant metastases. The actuarial 2-year and 5-year survivals of the 14 patients assessed were 64% and 56% respectively.

Adolescent↗
PubMed1984

Multiple cerebral hydatid cysts.

A 39-year-old woman was admitted to hospital with headaches, vomiting, psychic impairment and diplopia. Three hydatid cysts of the lung had been previously removed. An avascular mass in the left hemisphere with left-to-right displacement of the anterior cerebral arteries was noted during a brain angioscintigraphy. A computed tomography (CT) brain scan showed two cystic lesions situated in the left-frontal and occipital regions. A CT abdominal scan showed multiple cysts in the liver, spleen and both kidneys. At operation, two brain cysts were totally extirpated without rupture. The definite pathological diagnosis was secondary hydatid cysts. The headaches, vomiting and diplopia were persistent in the post-operative period. Seven days after the operation, a CT brain scan showed an infratentorial cyst. The patient rejected any surgical intervention.

Adult↗
PubMed1982

Plasma electrolyte content and concentration during treadmill exercise in humans.

Five healthy males volunteered to exercise for 20 min on a motor-driven treadmill at five submaximal intensities (30, 45, 60, 75, and 90% of VO2 max). Peripheral venous blood samples were drawn from an indwelling catheter prior to and at 9, 14, and 19 min of each exercise bout. Blood samples were assayed for whole-blood hemoglobin, total plasma protein concentrations, and hematocrit, with plasma water concentration calculated from these values. The plasma concentration of the electrolytes sodium (Na+), potassium (K+), total calcium (Catot), ionized calcium (Ca2+), chloride (Cl-), and inorganic phosphorus (Pi) were also determined. With plasma and blood volumes the total plasma contents of each of the measured constituents and the concentration of each electrolyte per liter of water were calculated. Statistically significant linear increases in plasma concentrations of Na+, K+, and Cl- relative to exercise intensity were observed, with linear decreases in plasma contents of Na+ and Cl- and linear increases in K+ content. Plasma Pi concentration decreased with a Pi increased content, with plasma Catot concentration elevated at the highest two work loads. Plasma Catot content increased linearly with exercise intensity and duration. Plasma water concentration and content decreased with exercise intensity, resulting in no change in electrolyte concentration per liter of water except at the highest two exercise intensities. These data suggest that extrapolation from plasma electrolyte concentration to muscle concentration and/or content is not supported. Changes in plasma volume and plasma water must be considered when postulating a role for electrolytes in the physiological responses of the human to exercise.

Adult↗
PubMed1980

Thermoregulation during rest and exercise in different postures in a hot humid environment.

The time course of whole-body sweating and thermal regulation during rest and exercise in a hot humid environment was investigated in three body postures. After 45 min rest in the upright, low-sit, or supine posture, five unacclimatized men exercised for 45 min on a bicycle ergometer in the same posture in an environment of 49.5 degrees C, 28.9 Torr. Exercise was performed at two different work loads, corresponding to about 30 and 45% of VO2max. During exercise auditory canal temperature, rectal temperature, and mean skin temperature increased linearly being highest in the supine and lowest in the upright posture. Percentage of evaporated sweat from the skin to secreted sweat was 65% in upright, 52% in the low-sit, and only 46% in the supine posture during the last 20 min of exercise regardless of work load. The time course of the rate of body heat storage was different from predictions based on the thermal balance equation. Evaporative heat loss was not 100% effective in cooling the skin surface.

Adult↗