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1.
Am J Transplant ; 17(2): 341-352, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27743487

RESUMEN

Ischemia-reperfusion injury is unavoidably caused by loss and subsequent restoration of blood flow during organ procurement, and prolonged ischemia-reperfusion injury IRI results in increased rates of delayed graft function and early graft loss. The endogenously produced gasotransmitter, hydrogen sulfide (H2 S), is a novel molecule that mitigates hypoxic tissue injury. The current study investigates the protective mitochondrial effects of H2 S during in vivo cold storage and subsequent renal transplantation (RTx) and in vitro cold hypoxic renal injury. Donor allografts from Brown Norway rats treated with University of Wisconsin (UW) solution + H2 S (150 µM NaSH) during prolonged (24-h) cold (4°C) storage exhibited significantly (p < 0.05) decreased acute necrotic/apoptotic injury and significantly (p < 0.05) improved function and recipient Lewis rat survival compared to UW solution alone. Treatment of rat kidney epithelial cells (NRK-52E) with the mitochondrial-targeted H2 S donor, AP39, during in vitro cold hypoxic injury improved the protective capacity of H2 S >1000-fold compared to similar levels of the nonspecific H2 S donor, GYY4137 and also improved syngraft function and survival following prolonged cold storage compared to UW solution. H2 S treatment mitigates cold IRI-associated renal injury via mitochondrial actions and could represent a novel therapeutic strategy to minimize the detrimental clinical outcomes of prolonged cold IRI during RTx.


Asunto(s)
Isquemia Fría , Supervivencia de Injerto , Sulfuro de Hidrógeno/administración & dosificación , Trasplante de Riñón , Mitocondrias/metabolismo , Preservación de Órganos/métodos , Daño por Reperfusión/prevención & control , Animales , Gasotransmisores/administración & dosificación , Riñón/irrigación sanguínea , Masculino , Ratas , Ratas Endogámicas BN , Ratas Endogámicas Lew , Daño por Reperfusión/patología , Trasplante Homólogo
2.
Pharmacol Res ; 113(Pt A): 686-694, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27720932

RESUMEN

Hydrogen sulfide (H2S) has been highlighted as an endogenous signaling molecule and we have previously found that it can inhibit histamine-mediated itching. Pruritus is the most common symptom of cutaneous diseases and anti-histamines are the usual treatment; however, anti-histamine-resistant pruritus is common in some clinical settings. In this way, the involvement of mediators other than histamine in the context of pruritus requires new therapeutic targets. Considering that the activation of proteinase-activated receptor 2 (PAR-2) is involved in pruritus both in rodents and humans, in this study we investigated the effect of H2S donors on the acute scratching behavior mediated by PAR-2 activation in mice, as well as some of the possible pharmacological mechanisms involved. The intradermal injection of the PAR-2 peptide agonist SLIGRL-NH2 (8-80nmol) caused a dose-dependent scratching that was unaffected by intraperitoneal pre-treatment with the histamine H1 antagonist pyrilamine (30mg/kg). Co-injection of SLIGRL-NH2 (40nmol) with either the slow-release H2S donor GYY4137 (1 and 3nmol) or the spontaneous donor NaHS (1 and 0.3nmol) significantly reduced pruritus. Co-treatment with the KATP channel blocker glibenclamide (200nmol) or the nitric oxide (NO) donor sodium nitroprusside (10nmol) abolished the antipruritic effects of NaHS; however, the specific soluble guanylyl cyclase inhibitor ODQ (30µg) had no significant effects. The transient receptor potential ankyrin type 1 (TRPA1) antagonist HC-030031 (20µg) significantly reduced SLIGRL-NH2-induced pruritus; however pruritus induced by the TRPA1 agonist AITC (1000nmol) was unaffected by NaHS. Based on these data, we conclude that pruritus secondary to PAR-2 activation can be reduced by H2S, which acts through KATP channel opening and involves NO in a cyclic guanosine monophosphate (cGMP)-independent manner. Furthermore, TRPA1 receptors mediate the pruritus induced by activation of PAR-2, but H2S does not interfere with this pathway. These results provide additional support for the development of new therapeutical alternatives, mainly intended for treatment of pruritus in patients unresponsive to anti-histamines.


Asunto(s)
Sulfuro de Hidrógeno/farmacología , Oligopéptidos/farmacología , Prurito/tratamiento farmacológico , Receptor PAR-2/metabolismo , Animales , Modelos Animales de Enfermedad , Gliburida/farmacocinética , Histamina/metabolismo , Antagonistas de los Receptores Histamínicos/farmacología , Isotiocianatos/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Morfolinas/farmacología , Nitroprusiato/farmacología , Compuestos Organotiofosforados/farmacología , Prurito/metabolismo , Canales de Potencial de Receptor Transitorio/metabolismo
3.
Cancer Genet ; 260-261: 30-36, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34852986

RESUMEN

BACKGROUND: It is likely that additional genes for hereditary breast cancer can be identified using a discordant sib pair design. Using this design we identified individuals harboring a rare PMS1 c.605G>A variant previously predicted to result in loss of function. OBJECTIVES: A family-based design and predictive algorithms were used to prioritize candidate variants possibly associated with an increased risk of hereditary breast cancer. Functional analyses were performed for one of the candidate variants, PMS1 c.605G>A. METHODS: 1) 14 discordant sister-pairs from hereditary breast cancer families were identified. 2) Whole exome sequencing was performed and candidate risk variants identified. 3) A rare PMS variant was identified in 2 unrelated affected sisters but no unaffected siblings. 4) Functional analysis of this variant was carried out using targeted mRNA sequencing. RESULTS: Genotype-phenotype correlation did not demonstrate tracking of the variant with cancer in the family. Functional analysis revealed no difference in exon 6 incorporation, which was validated by analyzing PMS1 allele specific expression. CONCLUSIONS: The PMS1 c.605G>A variant did not segregate with disease, and there was no variant-dependent impact on PMS1 exon 6 splicing, supporting this variant is likely benign. Functional analyses are imperative to understanding the clinical significance of predictive algorithms.


Asunto(s)
Neoplasias de la Mama/genética , Secuenciación del Exoma/métodos , Perfilación de la Expresión Génica/métodos , Proteínas MutL/genética , Proteínas de Neoplasias/genética , Polimorfismo de Nucleótido Simple , Adulto , Algoritmos , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Mutación con Pérdida de Función , Persona de Mediana Edad , Linaje , Análisis de Secuencia de ARN , Hermanos
4.
Breast Cancer Res Treat ; 126(2): 453-61, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21221773

RESUMEN

We hypothesized that exemestane (EXE) would reduce mammographic breast density and have unique effects on biomarkers of bone and lipid metabolism. Healthy postmenopausal women were randomized to EXE (25 mg daily) or placebo (PLAC) for 12 months and followed for a total of 24 months. The primary endpoint was change in percent breast density (PD) between the baseline and 12-month mammograms and secondary endpoints were changes in serum lipid levels, bone biomarkers, and bone mineral density (BMD). Ninety-eight women were randomized (49 to EXE; 49 to PLAC) and 65 had PD data at baseline and 12 months. Among women treated with EXE, PD was not significantly changed from baseline at 6, 12, or 24 months and was not different from PLAC. EXE was associated with significant percentage increase from baseline in N-telopeptide at 12 months compared with PLAC. No differences in percent change from baseline in BMD (lumbar spine and femoral neck) were observed between EXE and PLAC at either 12 or 24 months. Patients on EXE had a significantly larger percent decrease in total cholesterol than in the PLAC arm at 6 months and in HDL cholesterol at 3, 6, and 12 months. No significant differences in percent change in LDL or triglycerides were noted at any time point between the two treatment arms. EXE administered for 1 year to healthy postmenopausal women did not result in significant changes in mammographic density. A reversible increase in the bone resorption marker N-telopeptide without significant change in bone specific alkaline phosphatase or BMD during the 12 months treatment period and 1 year later was noted. Changes in lipid parameters on this trial were modest and reversible.


Asunto(s)
Androstadienos/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Densidad Ósea/efectos de los fármacos , Huesos/metabolismo , Mama/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Lípidos/sangre , Posmenopausia/metabolismo , Fosfatasa Alcalina/sangre , Neoplasias de la Mama/prevención & control , Colágeno Tipo I/orina , Método Doble Ciego , Femenino , Humanos , Mamografía , Persona de Mediana Edad , Péptidos/orina
5.
Endocr Rev ; 5(1): 1-24, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6323158

RESUMEN

Corticosteroid feedback inhibits the brain-hypothalamo-pituitary units of the adrenocortical system. Naturally occurring corticosteroids may have their primary actions in vivo at brain and hypothalamic sites of feedback, whereas synthetic glucocorticoids that do not bind to transcortin may act primarily on corticotropes and regions of brain outside the blood-brain barrier. There appear to be three major time frames of corticosteroid action: fast, intermediate and slow. These time frames probably are the consequence of three separate mechanisms of corticosteroid action at feedback-sensitive sites. The rapidity of occurrence of fast feedback is not compatible with a nuclear site of corticosteroid action, and protein synthesis is not required. The action of CRF on ACTH release may be inhibited by a rapid effect of corticosteroids at the cell membrane. Since stimulated, but not basal, ACTH and CRF release are inhibited in vitro, the corticosteroids may inhibit some event in stimulus-secretion coupling (e.g., cAMP production). Intermediate feedback also decreases ACTH release in response to stimulation of the corticotrope, but does not affect ACTH synthesis; CRF synthesis and release both appear to be affected by the intermediate corticosteroid action. The mechanism of intermediate feedback requires the presence of a protein whose synthesis is corticosteroid-dependent; however, the role of this protein is unknown. Intermediate feedback, like fast feedback, apparently does not involve inhibition of total ACTH stores or the releasable pool of ACTH since basal secretion of ACTH is also not inhibited in vitro within this time domain. On the other hand, slow feedback apparently involves the classical genomic steroid mechanism of action; slow feedback reduces pituitary ACTH content by decreasing levels of mRNA encoding for POMC, the ACTH precursor molecule. Slow feedback, therefore, inhibits basal as well as stimulus induced ACTH secretion. Corticosteroid-induced inhibition of basal ACTH secretion has been shown to occur within 2 h in vivo but not in vitro. The time course and sensitivity of this feedback effect is different than that demonstrated for stimulus induced secretion. This difference suggests that basal secretion is activated by different pathways to (CRF and) ACTH secretion. There is some evidence that suggests that whereas comparator elements are not reset during stress, a comparator element is reset during the course of the circadian rhythm so that different basal levels of steroid are achieved.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Corticoesteroides/fisiología , Hormona Adrenocorticotrópica/metabolismo , Corticoesteroides/metabolismo , Corticoesteroides/farmacología , Animales , Sitios de Unión , Encéfalo/metabolismo , Encéfalo/fisiología , Ritmo Circadiano , Hormona Liberadora de Corticotropina/metabolismo , Retroalimentación , Humanos , Hipotálamo/efectos de los fármacos , Hipotálamo/fisiología , Ratones , Modelos Biológicos , Hipófisis/efectos de los fármacos , Hipófisis/fisiología , Sistema Hipófiso-Suprarrenal/fisiología , Ratas , Estrés Fisiológico/fisiopatología
6.
J Clin Invest ; 71(4): 859-66, 1983 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6300189

RESUMEN

We have tested the effect of physiological increases in plasma corticosteroids in conscious dogs on the levels of basal and hypoglycemia-stimulated adrenocorticotropic hormone (ACTH) 2 h later. Increases in plasma corticosteroids, produced by infusion of alpha-1-24 ACTH or corticosteroids for 40 min, suppressed basal and stimulated ACTH levels. The magnitude of inhibition produced by an increase in plasma corticosteroids induced by the infusion of ACTH was equivalent to the inhibition produced by the same increase in plasma corticosteroids induced by corticosteroid infusion. The infusions did not affect basal plasma glucose concentrations or the decrease in plasma glucose concentrations after administration of 0.1 U insulin/kg. Basal ACTH concentration was less sensitive than hypoglycemia-stimulated ACTH concentration to corticosteroid-induced suppression. Basal and stimulated secretion were significantly inhibited in all dogs after approximately half-maximal increases in plasma corticosteroids; maximum inhibition occurred after maximal increases in plasma corticosteroids. Therefore, physiological increments in plasma corticosteroids, similar to those produced by acute stress, are effective suppressors of subsequent stress-induced ACTH secretion.


Asunto(s)
Corticoesteroides/administración & dosificación , Hormona Adrenocorticotrópica/administración & dosificación , Corticoesteroides/sangre , Corticoesteroides/fisiología , Hormona Adrenocorticotrópica/sangre , Hormona Adrenocorticotrópica/fisiología , Animales , Glucemia/análisis , Depresión Química , Perros , Relación Dosis-Respuesta a Droga , Retroalimentación , Femenino , Hipoglucemia/metabolismo , Hipoglucemia/fisiopatología , Insulina/administración & dosificación , Masculino
7.
J Clin Oncol ; 13(12): 2906-15, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8523054

RESUMEN

PURPOSE: To determine if a delay of irradiation to the intact breast for administration of adjuvant chemotherapy results in increased local recurrence in breast cancer. PATIENTS AND METHODS: The records of 262 women with 264 cases of breast cancer were reviewed. Group I contained 105 patients treated with conservative surgery, chemotherapy, and radiotherapy. Group II contained 157 patients (used as a concurrent control) treated with conservative surgery and radiotherapy only. Eighty-nine percent of subjects in group I received all chemotherapy before radiotherapy. Fifty-eight percent of patients received hormone therapy. Seventy-one percent of patients had negative surgical margins, and 74% had negative lymph nodes. For group I, conservative surgery-radiotherapy intervals in months were less than 1 (five, 5%), > or = 1 to less than 3 (10, 9%), > or = 1 to less 6 (48, 46%), and > or = 6 (42, 40%), mean of 5. For group II, the intervals were less than 1 (20, 13%), > or = 1 to less than 3 (123, 79%), > or = 3 to less than 6 (11, 7%), and > or = 6 (two, 1%), mean of 1.5. RESULTS: Thirty patients (11.5%) have disease recurrence (19 distant [6%] and 12 local [5%]). There were no significant differences in local recurrence (group I, four [4%]; group II, eight [5%]; difference not significant). There were no significant differences in local recurrence in any surgery-radiotherapy interval within each group. Although we found marginal increases in the percentage of local recurrences in group I patients (with prolonged surgery-radiotherapy intervals) who had positive margins, positive lymph nodes, and tumor size more than 2 cm versus group II (without prolonged surgery-radiotherapy intervals), these results were not significant. CONCLUSION: We could not identify any surgery-radiotherapy interval that resulted in increased local recurrence if radiotherapy was delayed for administration of adjuvant chemotherapy in breast cancer patients. Because of the heterogenous population of breast cancer patients, our results also support the need for further study to determine the optimum integration of radiotherapy and chemotherapy in the management of the conservatively treated breast.


Asunto(s)
Neoplasias de la Mama/terapia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Quimioterapia Adyuvante , Terapia Combinada , Antagonistas de Estrógenos/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática , Mastectomía Segmentaria , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Pronóstico , Radioterapia Adyuvante , Estudios Retrospectivos , Análisis de Supervivencia , Tamoxifeno/uso terapéutico , Factores de Tiempo
8.
J Clin Oncol ; 16(7): 2417-25, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9667259

RESUMEN

PURPOSE: Previous studies of mutations in BRCA1 or BRCA2 have used detection methods that may underestimate the actual frequency of mutations and have analyzed women using heterogeneous criteria for risk of hereditary cancer. PATIENTS AND METHODS: A total of 238 women with breast cancer before age 50 or ovarian cancer at any age and at least one first- or second-degree relative with either diagnosis underwent sequence analysis of BRCA1 followed by analysis of BRCA2 (except for 27 women who declined analysis of BRCA2 after a deleterious mutation was discovered in BRCA1). Results were correlated with personal and family history of malignancy. RESULTS: Deleterious mutations were identified in 94 (39%) women, including 59 of 117 (50%) from families with ovarian cancer and 35 of 121 (29%) from families without ovarian cancer. Mutations were identified in 14 of 70 (20%) women with just one other relative who developed breast cancer before age 50. In women with breast cancer, mutations in BRCA1 and BRCA2 were associated with a 10-fold increased risk of subsequent ovarian carcinoma (P = .005). CONCLUSION: Because mutations in BRCA1 and BRCA2 in women with breast cancer are associated with an increased risk of ovarian cancer, analysis of these genes should be considered for women diagnosed with breast cancer who have a high probability of carrying a mutation according to the statistical model developed with these data.


Asunto(s)
Neoplasias de la Mama/genética , Genes BRCA1/genética , Neoplasias Ováricas/genética , Adulto , Análisis Mutacional de ADN , Femenino , Pruebas Genéticas , Humanos , Modelos Logísticos , Anamnesis , Persona de Mediana Edad , Factores de Riesgo
9.
Clin Cancer Res ; 5(11): 3419-24, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10589753

RESUMEN

This Phase I study was designed to determine the maximally tolerated dose (MTD) of paclitaxel with standard doses of cisplatin and etoposide for patients with untreated extensive stage small cell lung cancer (SCLC). Secondary objectives were to determine the toxicities, response rate, response duration, and overall survival in this cohort. Twenty-eight SCLC patients were enrolled into four dose levels. All patients received a fixed dose of cisplatin at 80 mg/m2, i.v., day 1. The first group received etoposide 50 mg/m2, i.v. day 1 and 100 mg/m2 p.o., days 2-3, whereas all subsequent groups received etoposide 80 mg/m2, i.v., day 1 and 160 mg/m2, p.o., days 2-3. The paclitaxel starting dose was 135 mg/m2, i.v., over a 3-h period and was escalated to 175 and 200 mg/m2. Cycles were repeated every 21 days for a maximum of six cycles. Granulocyte-colony stimulating factor was not given prophylactically but was allowed in subsequent cycles according to the American Society of Clinical Oncologists guidelines. All 28 SCLC patients were evaluable for toxicity, and 23 patients were evaluable for response. Myelosuppression was the major toxicity, with grade 4 neutropenia occurring in 23 of 28 patients (82%), but febrile neutropenia was uncommon and developed in 4 patients (14%). Grade 4 thrombocytopenia and anemia were rare, occurring as isolated events in one patient each. Dose-limiting peripheral neuropathy was observed at a paclitaxel dose of 200 mg/m2. Grade 4 nausea/vomiting and diarrhea were also noted at this dose level. Five patients had complete responses (22%), and 14 patients had partial responses (61%). The overall response rate was 83% with a median time to progression of 7.5 months, a median survival of 10 months, and a 1-year survival rate of 39%. This three-drug combination of paclitaxel with cisplatin and etoposide is active with acceptable toxicity. Neurotoxicity was dose limiting at 200 mg/m2 of paclitaxel. Neutropenia was frequent but not associated with significant morbidity. The recommended doses for future clinical trials are 175 mg/m2 paclitaxel, i.v., over a 3-h period on day 1 with 80 mg/m2 cisplatin, i.v., on day 1 and 80 mg/m2 etoposide, i.v., on day 1 and 160 mg/m2 p.o. on days 2 and 3 with growth factor support. The Southwestern Oncology Group has instituted a Phase II study with this dose schedule.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carcinoma de Células Pequeñas/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Adulto , Anciano , Carcinoma de Células Pequeñas/mortalidad , Carcinoma de Células Pequeñas/patología , Cisplatino/administración & dosificación , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Etopósido/administración & dosificación , Femenino , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neutropenia/inducido químicamente , Neutropenia/prevención & control , Paclitaxel/administración & dosificación , Tasa de Supervivencia , Factores de Tiempo
10.
Diabetes Care ; 24(4): 726-32, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11315838

RESUMEN

OBJECTIVE: Chronic hyperglycemia is known to increase tissue glycation and diabetic complications, but controversy exists regarding the independent role of increased postprandial glucose excursions. To address this question, we have studied the effect of postprandial glycemic excursions (PPGEs) on levels of methylglyoxal (MG) and 3-deoxyglucosone (3-DG), two highly reactive precursors of advanced glycation end products (AGEs). RESEARCH DESIGN AND METHODS: We performed 4-month crossover studies on 21 subjects with type 1 diabetes and compared the effect of premeal insulin lispro or regular insulin on PPGEs and MG/3-DG excursions. PPGE was determined after standard test meal (STMs) and by frequent postprandial glucose monitoring. HbA1c and postprandial MG and D-lactate were measured by HPLC, whereas 3-DG was determined by gas chromatography/mass spectroscopy. RESULTS: Treatment with insulin lispro resulted in a highly significant reduction in PPGEs relative to the regular insulin-treated group (P = 0.0005). However, HbA1c levels were similar in the two groups, and no relationship was observed between HbA1c and PPGE (P = 0.93). Significant postprandial increases in MG, 3-DG, and D-lactate occurred after the STM. Excursions of MG and 3-DG were highly correlated with levels of PPGE (R = 0.55, P = 0.0002 and R = 0.61, P = 0.0004; respectively), whereas a significant inverse relationship was seen between PPGE and D-lactate excursions (R = 0.40, P = 0.01). Conversely, no correlation was observed between HbAlc and postprandial MG, 3-DG, or D-lactate levels. CONCLUSIONS: Increased production of MG and 3-DG occur with greater PPGE, whereas HbA1c does not reflect these differences. Reduced PPGE also leads to increased production of D-lactate, indicating a role for increased detoxification in reducing MG levels. The higher postprandial levels of MG and 3-DG observed with greater PPGE may provide a partial explanation for the adverse effects of glycemic lability and support the value of agents that reduce glucose excursions.


Asunto(s)
Glucemia/metabolismo , Desoxiglucosa/sangre , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hiperglucemia/epidemiología , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Piruvaldehído/sangre , Adolescente , Adulto , Anciano , Biomarcadores/sangre , Glucemia/efectos de los fármacos , Estudios Cruzados , Desoxiglucosa/análogos & derivados , Método Doble Ciego , Esquema de Medicación , Productos Finales de Glicación Avanzada/sangre , Humanos , Hiperglucemia/sangre , Hipoglucemiantes/administración & dosificación , Insulina/administración & dosificación , Insulina/análogos & derivados , Insulina Lispro , Persona de Mediana Edad , Periodo Posprandial , Análisis de Regresión
11.
Methods Enzymol ; 555: 233-51, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25747483

RESUMEN

Hydrogen sulfide (H2S) is an important gasotransmitter in both animals and plants. Many physiological events, including responses to stress, have been suggested to involve H2S, at least in part. On the other hand, numerous responses have been reported following treatment with H2S, including changes in the levels of antioxidants and the activities of transcription factors. Therefore, it is important to understand and unravel the events that are taking place downstream of H2S in signaling pathways. H2S is known to interact with other reactive signaling molecules such as reactive oxygen species (ROS) and nitric oxide (NO). One of the mechanisms by which ROS and NO have effects in a cell is the modification of thiol groups on proteins, by oxidation or S-nitrosylation, respectively. Recently, it has been reported that H2S can also modify thiols. Here we report a method for the determination of thiol modifications on proteins following the treatment with biological samples with H2S donors. Here, the nematode Caenorhabditis elegans is used as a model system but this method can be used for samples from other animals or plants.


Asunto(s)
Caenorhabditis elegans/efectos de los fármacos , Proteínas del Helminto/aislamiento & purificación , Sulfuro de Hidrógeno/farmacología , Procesamiento Proteico-Postraduccional , Compuestos de Sulfhidrilo/metabolismo , Animales , Conducta Animal/efectos de los fármacos , Caenorhabditis elegans/metabolismo , Disulfuros/química , Disulfuros/metabolismo , Electroforesis en Gel de Poliacrilamida , Fluoresceínas/química , Proteínas del Helminto/química , Proteínas del Helminto/metabolismo , Peróxido de Hidrógeno/farmacología , Sulfuro de Hidrógeno/metabolismo , Movimiento/efectos de los fármacos , Óxido Nítrico/metabolismo , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Coloración y Etiquetado/métodos , Compuestos de Sulfhidrilo/química , Sulfuros/química , Sulfuros/farmacología
12.
Endocrinology ; 113(2): 491-6, 1983 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6307641

RESUMEN

We have tested the efficacy of prior stress-induced increases in corticosteroids on inhibition of the ACTH response to hypoglycemia induced 2 h later. Five dogs were studied in each of five experiments. In each experiment, there were two stimulus periods; in the first, 5% dextrose, 3 or 10 micrograms/kg X min nitroprusside, or 0.05 or 0.10 U/kg insulin was administered, and in the second, 0.10 U/kg insulin was administered. Whereas prior infusion of 5% dextrose did not affect the subsequent ACTH response to 0.10 U/kg insulin, prior stimulation of the pituitary-adrenal axis had a significant effect on the subsequent ACTH response to 0.10 U/kg insulin. The integrated ACTH response to hypoglycemia was significantly reduced by prior stimulation by either 10 micrograms/kg/min nitroprusside or 0.10 U/kg insulin, although the intensity of the hypoglycemia during the second stimulus period was not altered by any of the prior stimuli. Overall, the magnitude of the suppression of the pituitary-adrenal response to hypoglycemia was significantly related to the increase in plasma corticosteroids produced by the first stimulus, and was consistent with the degree of corticosteroid feedback inhibition of ACTH observed in previous studies after ACTH or corticosteroid infusion. Therefore, we conclude that prior stimulation of the hypothalamo-pituitary-adrenal axis of conscious dogs by hypotension or hypoglycemia inhibits subsequent responses in proportion to the corticosteroid feedback signal produced.


Asunto(s)
Corticoesteroides/sangre , Hormona Adrenocorticotrópica/metabolismo , Hipoglucemia/fisiopatología , Estrés Fisiológico/fisiopatología , Hormona Adrenocorticotrópica/sangre , Animales , Glucemia/análisis , Presión Sanguínea/efectos de los fármacos , Corticosterona/sangre , Perros , Femenino , Frecuencia Cardíaca/efectos de los fármacos , Insulina/farmacología , Cinética , Masculino , Nitroprusiato/farmacología
13.
Endocrinology ; 109(3): 818-24, 1981 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6266809

RESUMEN

We have measured changes in plasma glucose, ACTH, corticosteroids, and vasopressin and hematocrit after five doses of insulin in six conscious dogs. We found insulin dose-related changes for each of these responses (P less than 0.01, by two-way analysis of variance). The increases in plasma ACTH and hematocrit correlated to the decrease in plasma glucose; the increase in plasma vasopressin was more strongly correlated with the increases in plasma Na+ than with the decreases in plasma glucose. Each dog appeared to have a characteristic ACTH response curve; therefore, the relationship between plasma glucose and plasma ACTH responses varied among dogs, but was significant in five of six dogs studied. Maximal plasma corticosteroid responses occurred with submaximal plasma ACTH responses (200-600 pg/ml). A single dose of insulin produced reproducible changes in plasma ACTH when given to five dogs in three separate experiments over a 2- to 6-month period. In these experiments, the measurement of ACTH allowed us to distinguish three levels of response to insulin, whereas measurement of the corticosteroid response allowed us to distinguish only two levels of response.


Asunto(s)
Glándulas Suprarrenales/fisiología , Hipoglucemia/fisiopatología , Insulina/farmacología , Hipófisis/fisiología , 11-Hidroxicorticoesteroides/sangre , Hormona Adrenocorticotrópica/sangre , Animales , Arginina Vasopresina/sangre , Glucemia/metabolismo , Perros , Relación Dosis-Respuesta a Droga , Femenino , Hematócrito , Hipoglucemia/inducido químicamente , Cinética , Masculino
14.
Am J Med ; 87(5A): 274S-277S, 1989 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-2589377

RESUMEN

A randomized study of treatment with ciprofloxacin combined with benzylpenicillin (CB) versus a standard regimen of netilmicin combined with piperacillin (NP) as first-line empiric therapy was conducted in febrile neutropenic patients. Ninety-six patients were evaluable for determination of efficacy: 50 patients received CB and 46 patients received NP. There was no significant difference between the two groups in terms of age or primary diagnosis. Overall clinical response rate at the end of therapy was 66 percent for CB and 65 percent for NP. Microbiologic assessment revealed more pathogens eradicated by CB (64 percent) and fewer persisting (4 percent) than in the NP group (52 percent eradicated, 13 percent persisting). Only 10 percent of patients in the CB group had treatment-related adverse reactions as opposed to 28 percent of the NP-treated patients; these were predominantly renal impairment and were likely to have been due to the aminoglycoside. Staphylococcus epidermidis was the most commonly isolated pathogen, accounting for 38 percent of all isolates and 30 percent of all patients in whom treatment failed. Although streptococci accounted for 18 percent of the isolated pathogens, no treatment failures or superinfections were due to these organisms. This indicates an advantage of combining ciprofloxacin with benzylpenicillin. We conclude that the CB regimen is as effective as the NP treatment and is associated with fewer side effects.


Asunto(s)
Infecciones Bacterianas/tratamiento farmacológico , Ciprofloxacina/administración & dosificación , Fiebre/tratamiento farmacológico , Neutropenia/complicaciones , Adulto , Agranulocitosis , Bacterias/aislamiento & purificación , Ciprofloxacina/efectos adversos , Quimioterapia Combinada , Humanos , Infusiones Intravenosas , Persona de Mediana Edad , Netilmicina/administración & dosificación , Penicilina G/administración & dosificación , Piperacilina/administración & dosificación , Distribución Aleatoria
15.
Lung Cancer ; 30(2): 135-44, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11086207

RESUMEN

The role of both primary and secondary cigarette smoke exposure in the causation of lung cancer appears certain. An estimated 90% of lung cancer is attributed to cigarette smoke. Remarkably, however, less then 20% of cigarette smokers develop lung cancer. Investigators have suggested that a genetic predisposition to lung cancer may contribute to familial aggregation of this cancer. To understand the contribution of familial aggregation to this type of cancer and potentially identify individuals and families, which may be important in identifying gene(s) responsible for lung cancer, we developed criteria for identification of high-risk families. We have tested the feasibility and utility of these criteria at three Denver, CO hospitals with very different patient populations. Four hundred eighteen individuals were diagnosed with lung cancer at these three hospitals between 1/1/95 and 8/31/95. Twenty-nine percent of individuals expired prior to the time of initial contact. Family history data were obtained on 182 individuals. To be considered positive (suggesting possible autosomal dominant inheritance of lung cancer), families must have at least two first-degree relatives with lung cancer, one of which must be diagnosed before the age of 55. Seventeen of 182 (9.3%) families in the study population met these criteria. We reviewed the remaining family histories that did not meet the established criteria and identified another 2.3% (5/182) of families had evidence for autosomal dominant transmission of lung cancer. An additional 15% (23/182) of families had histories which could not be classified without further information. This study suggests that at least 11.6% of individuals diagnosed with lung cancer will have a positive family history of lung cancer. Use of the criteria developed for this study may lead to an underestimation of the inherited etiology of lung cancer.


Asunto(s)
Predisposición Genética a la Enfermedad , Neoplasias Pulmonares/genética , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Pruebas Genéticas , Humanos , Masculino , Persona de Mediana Edad , Linaje , Proyectos Piloto
16.
Oncology (Williston Park) ; 15(7): 889-902; discussion 902, 905-7, 911-13, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11499690

RESUMEN

Assessing the risk of breast and ovarian cancer starts with obtaining a complete and accurate family history. This can reveal evidence of inherited cancer risk. The highest risk of cancer is associated with germ-line abnormalities in several genes, including BRCA1, BRCA2, and TP53. Moderate-risk genes associated with syndromes that are inherited in an autosomal dominant pattern (such as Cowden's disease, hereditary non-polyposis colorectal cancer, Muir-Torre syndrome, and Peutz-Jeghers syndrome) exhibit lower penetrance and thus less risk of breast and/or ovarian cancer. Low-risk genes likely require significant environmental exposure, and although they are associated with the lowest risk of cancer, they account for more cancer than high- and moderate-risk genes. Lifetime risks for breast or ovarian cancer can be estimated. The Gail and Claus models, the more widely utilized models for calculation of lifetime breast cancer risk, are discussed. Models are also available for determining the likelihood of finding a BRCA1/2 mutation (the BRCAPRO and Myriad models). Appropriate candidates for testing include affected individuals who are most likely to have a hereditary form of cancer. Testing should proceed only after a thorough discussion of the risks, benefits, and limitations of testing. Risk-reducing options are available to women with a strong family history of breast and ovarian cancer. These options include high-risk screening, chemoprevention, and prophylactic surgery.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias Ováricas/genética , Distribución por Edad , Edad de Inicio , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/prevención & control , Femenino , Genes BRCA1 , Genes BRCA2 , Genes p53 , Pruebas Genéticas , Humanos , Mutación , Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/prevención & control , Penetrancia , Riesgo
17.
Genet Test ; 4(3): 265-72, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11142757

RESUMEN

We sought to understand better the impact of genetic testing and counseling in a group of women who had early breast cancer (age <50) or ovarian cancer and a family history of cancer. Thirty-five women underwent genetic counseling and genetic testing for BRCA1/2 at the University of Colorado Cancer Center, Hereditary Cancer Clinic. Psychological assessment (IES and Hopkins Symptom Checklist) was made before counseling, and 1 month after genetic test results were reported to women. A statistically significant decrease in anxiety was evidenced 1 month after results were given (p = 0.024). Decreased intrusive thoughts related to genetic testing were seen only for those testing negative (p = 0.0003). Women diagnosed with cancer less than 1 year prior to genetic testing experienced the greatest cancer-specific distress (p = 0.01) and distress related to genetic testing (p = not significant). Satisfaction with the counseling and testing process was high. In conclusion, genetic testing and counseling can occur with little anxiety and stress. However, women less than 1 year from a cancer diagnosis will experience the greatest distress associated with genetic testing and counseling. Women who are considering genetic testing and counseling close to a diagnosis of cancer may require greater psychological support.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Genes BRCA1 , Asesoramiento Genético , Pruebas Genéticas , Neoplasias Ováricas/diagnóstico , Adulto , Anciano , Neoplasias de la Mama/genética , Neoplasias de la Mama/psicología , Análisis Mutacional de ADN , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/genética , Neoplasias Ováricas/psicología , Proyectos Piloto , Estudios Prospectivos
18.
N Z Med J ; 99(801): 326-30, 1986 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-2872642

RESUMEN

The accumulated data from a defined medical examination of 561 male alcoholics is reported and analysed using a simple artificial index of the severity of alcohol injury which describes each patient in a single parameter; the alcohol related toxicity quotient (ARTq). The results indicate that after an average of twelve days sobriety, the clinical assessment of ataxia is a more consistent guide to chronic alcoholism than a previous history of intervention by a therapeutic agency or the more complex tests of mean cell volume (MCV) or gamma glutamyl transpeptidase (GGT). However, the ARTq correlates with each of these indices better than they intercorrelate between themselves. The findings are discussed in relation to the pathological lesions and natural history of alcoholism.


Asunto(s)
Alcoholismo/diagnóstico , Examen Físico , Adulto , Alcoholismo/complicaciones , Ataxia/etiología , Computadores , Índices de Eritrocitos , Estudios de Evaluación como Asunto , Humanos , L-Lactato Deshidrogenasa/sangre , Masculino , Persona de Mediana Edad , Probabilidad , Análisis de Regresión , Fumar , gamma-Glutamiltransferasa/sangre
19.
J Homosex ; 38(3): 19-40, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10546970

RESUMEN

The discourse of the new sciences of homosexuality interacts with, reproduces, and sometimes challenges other discourses that inform and intersect it--popular discussions of scientific discoveries, legal discourse, debates about gay and lesbian identity, and religious discourse. Despite their different intentions and vocabularies, what links the discourse of the Christian right to that of contemporary sexology research and its popularized versions is its reproduction of a binary gender system, in which women are figured as both within and outside of "nature." Researchers in gay, lesbian, and bisexual sexuality can make a significant contribution by exposing the ways their research contends with discursive practices that have a context and a history (in connections between Aquinas's theology and Aristotle's science, for example). The narrative, rooted in traditional Christian theology and early Western science, that produces gender as binary and heterosexuality as normative can be rewritten to reveal the constructedness of both gender and sexuality.


Asunto(s)
Cristianismo , Homosexualidad , Humanos , Política , Religión y Psicología , Religión y Sexo
20.
Public Health Genomics ; 16(3): 75-82, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23328214

RESUMEN

BACKGROUND: Risk stratification based on family history is a feature of screening guidelines for a number of cancers and referral guidelines for genetic counseling/testing for cancer risk. AIMS: Our aim was to describe primary care physician perceptions of their role in managing cancer risk based on family history. METHODS: Structured interviews were conducted by a medical anthropologist with primary care physicians in 3 settings in 2 north-eastern states. Transcripts were systematically analyzed by a research team to identify major themes expressed by participants. RESULTS: Forty interviews were conducted from May 2003 through May 2006. Physicians provided a diversity of views on roles in management of cancer risk based on family history, management practices and patient responses to risk information. They also provided a wide range of perspectives on criteria used for referral to specialists, types of specialists referred to and expected management roles for referred patients. CONCLUSION: Some primary care physicians appeared to make effective use of family history information for cancer risk management, but many in this sample did not. Increased focus on efficient assessment tools based on recognized guidelines, accessible guides to management options, and patient education and decision aids may be useful directions to facilitate broader use of family history information for cancer risk management.


Asunto(s)
Predisposición Genética a la Enfermedad , Anamnesis , Neoplasias/epidemiología , Administración de la Práctica Médica/organización & administración , Atención Primaria de Salud/organización & administración , Derivación y Consulta , Femenino , Humanos , Masculino , Medicina , Neoplasias/genética , Pautas de la Práctica en Medicina , Factores de Riesgo
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