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1.
Andrologia ; 40(4): 203-8, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18727729

RESUMEN

Semen samples from 60 infertile men were examined by flow cytometry following propidium iodide staining. Of these, 23 samples contained young haploid cells. Transition proteins (TP1 and/or TP2) were detected in 12 of these, using immunohistochemical staining. The presence of TPs in spermatids in semen indicates inhibition in the differentiation pathway from round spermatids to spermatozoa. Cells of this type were found in semen from patients with nonobstructive azoospermia, severe to extreme cases of oligozoospermia, asthenozoospermia and teratozoospermia.


Asunto(s)
Proteínas Cromosómicas no Histona/metabolismo , Infertilidad Masculina/metabolismo , Semen/metabolismo , Espermatogénesis/fisiología , Diferenciación Celular/fisiología , Humanos , Infertilidad Masculina/patología , Masculino , Espermátides/patología , Espermatozoides/patología
2.
Immunol Lett ; 10(1): 1-5, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-4007959

RESUMEN

A male inhibitory material (HuSePl-Frl) was separated from normal human seminal plasma by gel filtration on Sephadex G-100. This material has high avidity for cell membranes of human red blood cells (RBC). In vitro, PHA-M-induced blast transformation of human lymphocytes is inhibited by small quantities of HuSePl-Frl. This inhibition was also evident when RBC coated with HuSePl-Frl is added to mitogen stimulated lymphocytes in cultures. Small quantities of HuSePl-Frl are inhibitory to natural killer (NK) cell activation. The modulating role of the HuSePl-Frl in preventing the spermatozoal rejection during fertilization is discussed.


Asunto(s)
Inmunidad Innata , Células Asesinas Naturales/inmunología , Semen/inmunología , Citotoxicidad Inmunológica , Eritrocitos/inmunología , Humanos , Inmunosupresores , Activación de Linfocitos , Masculino
3.
Ann N Y Acad Sci ; 865: 266-73, 1998 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-9928021

RESUMEN

Pituitary stimulating adenylate cyclase (PACAP) is a major regulatory peptide with two active molecular forms: PACAP-27 and PACAP-38. Both molecular forms promote neuronal survival and protect against neurotoxicity. Based on our previous hybrid peptide strategy in designing vasoactive intestinal peptide (VIP) antagonists, novel PACAP analogues were synthesized (neurotensin6-11 PACAP7-27 and neurotensin6-11 PACAP7-38). In addition to the hybrid modification, the methionine in position 17 was replaced by norleucine (Nle). Treatment of rat cerebral cortical cultures for five days with the putative PACAP antagonists (1 nM) resulted in a 35-45% reduction in neuronal cell counts as compared to controls. Neuronal cell death was already obtained at picomolar concentrations for the neurotensin6-11 PACAP7-27 antagonist with 70% death at 10(-8) M. Co-administration of the PACAP hybrid analogue with picomolar amounts of PACAP-27 or Nle17-PACAP-27 attenuated the reduction in neuronal cell counts. While the protective effects of both analogues exhibited a peak at 1 pM concentrations, the Nle-containing agonist displayed a broader range of active concentrations (10(-12)M-10(-9) M). The putative PACAP antagonist also inhibited sperm motility (golden hamster) in a dose-dependent manner as assessed in vitro. Complete inhibition was observed at 10 microM, suggesting a role for PACAP in sperm motility and sexual function. Thus, previous findings of a large number of PACAP and PACAP receptors in the nervous system and the reproductive system are now correlated with a function in neuronal survival and sperm motility. The structure-activity studies suggest that the methionine in position 17 and the first six amino acids are important in the determination of PACAP activity, knowledge that may facilitate PACAP-based drug design.


Asunto(s)
Neuronas/efectos de los fármacos , Neuropéptidos/farmacología , Péptidos/toxicidad , Motilidad Espermática/efectos de los fármacos , Secuencia de Aminoácidos , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Corteza Cerebral/citología , Corteza Cerebral/fisiología , Cricetinae , Masculino , Mesocricetus , Datos de Secuencia Molecular , Neuronas/citología , Neuropéptidos/antagonistas & inhibidores , Neuropéptidos/química , Fármacos Neuroprotectores/farmacología , Fragmentos de Péptidos/farmacología , Péptidos/síntesis química , Péptidos/química , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa , Ratas
4.
Fertil Steril ; 27(1): 9-13, 1976 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1245248

RESUMEN

Carnitine determinations in human seminal fluid were shown to be useful in assessing epididymal and seminal vesicle function and in locating blockages in the male reproductive tract. The carnitine concentrations in 50 samples of seminal fluid ranged from 15 to 530 mug/ml (as carnitine-HCl). The patients could be divided into four classes. Patients with normal seminal vesicle and epididymal function had values of 250 mug/ml or above. Those with a defective epididymis and a functional seminal vesicle had intermediate carnitine levels (100 to 200 mug/ml) and normal fructose values in the seminal fluid. Patients with a defective seminal vesicle but a functional epididymis had intermediate carnitine concentrations and low fructose levels. Extremely low carnitine values (less than 100 mug/ml) were found in seminal fluid from patients whose epididymis and seminal vesicle both were defective. The possible role of carnitine in sperm maturation was discussed.


Asunto(s)
Carnitina/metabolismo , Epidídimo/metabolismo , Semen/metabolismo , Vesículas Seminales/metabolismo , Fosfatasa Ácida/metabolismo , Epididimitis/enzimología , Epididimitis/metabolismo , Fructosa/metabolismo , Humanos , Infertilidad Masculina/enzimología , Infertilidad Masculina/metabolismo , Inositol/metabolismo , Masculino , Oligospermia/enzimología , Oligospermia/metabolismo , Semen/enzimología , Vesículas Seminales/enzimología
5.
Fertil Steril ; 36(2): 214-8, 1981 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-6114878

RESUMEN

Carnitine and its short-chain acyl esters were assayed in semen from normospermic and azoospermic men. Extremely low concentrations of free carnitine and acylcarnitine were found in semen from patients with obstructive azoospermia where the ejaculate was primarily of prostatis origin, and low values were also obtained in obstruction of the vas deferens, where the epididymal contents were not ejaculated. Semen from patients whose azoospermia was caused by testicular dysfunction had low acylcarnitine concentrations and normal levels of free carnitine in most cases, but a group of patients with severe testicular failure (including cases of Klinefelter syndrome and cryptorchidism) had low semen free carnitine concentrations. Whereas treatment with human chorionic gonadotropin increased serum testosterone levels in azoospermic patients, it did not increase the free carnitine concentration in semen, although it increased the proportion of carnitine found in acylcarnitines.


Asunto(s)
Carnitina , Oligospermia/diagnóstico , Semen/análisis , Acetilcarnitina , Gonadotropina Coriónica/uso terapéutico , Criptorquidismo/diagnóstico , Hormona Folículo Estimulante/sangre , Humanos , Síndrome de Klinefelter/diagnóstico , Masculino , Vesículas Seminales/fisiología , Vasectomía
6.
Life Sci ; 74(9): 1119-26, 2004 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-14687652

RESUMEN

The number of cells in the S-phase fraction of the cell cycle reflects proliferative activity. Using flow cytometry histograms and the Phoenix M+ cell cycle program, the percent of cells in the S-phase fraction was measured in single cell suspensions prepared from testes of hamsters of different ages. A cyclical pattern with a period of 9 days, superimposed on another rhythm with a 38 day period was observed (p < 0.01) during hamster maturation and it disappeared after the second spermatogenic wave, where the S phase values reached a plateau. It was concluded that maturing animals passed through a stage in which testicular biological rhythm was involved. Therefore it was concluded that it takes approximately two spermatogenic waves before the proliferation rate in the testis reached a steady state.


Asunto(s)
Ciclo Celular/fisiología , Mesocricetus/fisiología , Periodicidad , Espermatogénesis/fisiología , Espermatozoides/citología , Factores de Edad , Animales , Cricetinae , Citometría de Flujo , Masculino , Maduración Sexual/fisiología , Testículo/fisiología
7.
J Stud Alcohol Suppl ; 13: 22-31, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10225485

RESUMEN

OBJECTIVE: This study examined early school-based academic and social variables with concurrent family conflict in predicting adolescent alcohol and other drug use. METHOD: 365 children were assessed initially in grades 2-4 on academic-related and social behavior variables using teacher ratings and rankings, peer nominations and ratings and direct observation of playground and classroom behavior. They were reassessed in grades 9-10, using interviews and questionnaires to determine the initiation and sequence of their use of alcohol, tobacco, marijuana and other hard drugs. RESULTS: In three sets of analyses, independently for males and females, lifetime abstainers were compared with adolescents who had used (1) only alcohol; (2) alcohol and tobacco; (3) alcohol, tobacco and marijuana; and (4) all three plus other hard drugs. The drug classifications represent a normative-deviant continuum of adolescent drug use. Constructs were developed for early academic and social predictors as well as concurrent family conflict. The results showed more wide-ranging academic and social difficulties during elementary school for children falling at the more deviant end of the drug use continuum. For girls, the concurrent home environment appeared to moderate the effect of early academic and social variables. CONCLUSIONS: Substance use established by ages 14-15 can be predicted by academic and social behavior displayed at ages 7-9. This suggests that prevention efforts for alcohol and other drugs may be more effective if directed at earlier antecedent behaviors rather than those that are concurrent with substance use.


Asunto(s)
Conducta del Adolescente/psicología , Alcoholismo/psicología , Salud de la Familia , Grupo Paritario , Trastornos Relacionados con Sustancias/psicología , Adolescente , Alcoholismo/etiología , Alcoholismo/prevención & control , Análisis de Varianza , Niño , Conducta Infantil/psicología , Femenino , Humanos , Masculino , Fumar Marihuana/psicología , Factores Sexuales , Fumar/psicología , Trastornos Relacionados con Sustancias/etiología , Trastornos Relacionados con Sustancias/prevención & control
8.
Contraception ; 42(6): 667-75, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2083489

RESUMEN

The effects of some antifertility sulphonamides on folate metabolism were investigated in the male rat. Subcutaneous injections of sulphanilamide at a dose of 150 mg/kg/day for 6 weeks produced a marked reduction in fertility of the treated animals. This effect was rapidly recovered by one week after drug withdrawal. Similar treatments with trimethoprim (30 mg/kg/day) or pyrimethamine (8 mg/kg/day) had virtually no effect on fertility. The synergistic effect of trimethoprim or pyrimethamine on the antifertility activity of sulphanilamide was not observed when the drugs were administered in combinations. Treatment with sulphapyridine (450 mg/kg/day for 6 weeks) failed to alter the levels of folate in the blood and the reproductive organs except the testes in which accumulation of folic acid occurred. The results suggest that the antifertility activity of sulphanilamide, sulphapyridine and perhaps some other sulphonamides is not associated with the inhibition of folate metabolism.


Asunto(s)
Ácido Fólico/metabolismo , Sulfonamidas/farmacología , Animales , Dimetilsulfóxido/farmacología , Combinación de Medicamentos , Epidídimo/metabolismo , Fertilidad/efectos de los fármacos , Hígado/metabolismo , Masculino , Próstata/metabolismo , Pirimetamina/farmacología , Ratas , Ratas Endogámicas F344 , Vesículas Seminales/metabolismo , Sulfacetamida/farmacología , Sulfamerazina , Sulfanilamida , Sulfanilamidas/farmacología , Sulfisoxazol/farmacología , Trimetoprim/farmacología
9.
Reprod Fertil Dev ; 9(4): 427-32, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9402252

RESUMEN

In this study, administration of pivalic acid or its sodium salt was found to decrease the L-carnitine concentration in the epididymal lumen of the hamster; it also tested whether this decrease affected sperm cell motility, chromatin structure, or fertilizing capacity. Provision of pivalic acid or its sodium salt (20 mM or 40 mM) in the drinking water of mature male golden hamsters for 30 days reduced (by 72%, 75%, and 83% in three experiments) the L-carnitine concentration of the cauda epididymidis but did not inhibit sperm chromatin condensation, as assessed by flow cytometry. The treatments did not alter the location of motile sperm in the epididymidis nor did they appreciably affect the motility of sperm obtained from the distal cauda epididymidis. The numbers and percentage of ova that reached the 2-cell stage 36-40 h after uterine insemination with spermatozoa from control and treated hamsters served as a measure of sperm fertility. Treatment with pivalic acid or sodium pivalate did not render male hamsters infertile although it appeared to reduce the fertilizing ability of their spermatozoa. These results suggest that the high concentration of L-carnitine present in the lumen of the cauda epididymidis is not required for maturation of sperm chromatin or development of sperm motility.


Asunto(s)
Carnitina/metabolismo , Cromatina/efectos de los fármacos , Epidídimo/efectos de los fármacos , Fertilidad/efectos de los fármacos , Ácidos Pentanoicos/farmacología , Motilidad Espermática/efectos de los fármacos , Animales , Cricetinae , Epidídimo/metabolismo , Masculino , Mesocricetus
10.
Gerontologist ; 30(5): 703-5, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2276647

RESUMEN

This paper conceptualizes separation-individuation conflicts in caregivers as behavior under the dual control of the nonverbal and verbal antecedents and consequences of others, (e.g., care receiver and professional staff) and the dysfunctional self-rules of the caregiver. Two types of treatment are described, in the context of a case study, that address each of two types of controlling events. The first type of treatment involved changing the care receiver's problem behaviors by training the nursing home staff in applied behavior analysis procedures. The second type involved teaching the caregiver to critically examine her self-rules by more accurately describing her own and others' behavior.


Asunto(s)
Ansiedad de Separación/terapia , Terapia Conductista/métodos , Atención Domiciliaria de Salud/psicología , Individualismo , Anciano , Enfermedad de Alzheimer/psicología , Ansiedad de Separación/psicología , Conflicto Psicológico , Femenino , Humanos , Teoría Psicológica
11.
Am J Med Sci ; 274(1): 55-9, 1977.
Artículo en Inglés | MEDLINE | ID: mdl-900156

RESUMEN

In order to determine the mechanism of elevated serum inositol in renal failure, the clearance values of inositol and of creatinine were measured in patients with normal kidney function and in those whose renal function was impaired due to varying causes. Mean serum inositol level in controls was 5.6 microgram/ml, and in patients with renal failure 28.6 microgram/ml. In control patients, inositol clearance was 2.8 ml/min, and tubular reabsorption of inositol was found to be over 97 percent. The inositol clearance of patients in renal failure varied from 0.62 to 17 ml/min. The ratio inositol clearance/creatinine clearance was elevated in uremic patients. Total amounts of inositol excreted in the urine of uremic patients were consistently higher than those excreted by control patients. The elevated serum inositol levels seen in renal failure were therefore not primarily caused by inability of the diseased kidney to excrete inositol.


Asunto(s)
Inositol/sangre , Riñón/fisiología , Uremia/sangre , Creatinina/sangre , Creatinina/orina , Humanos , Inositol/orina , Túbulos Renales/fisiología , Uremia/fisiopatología , Uremia/orina
12.
J Abnorm Child Psychol ; 27(4): 277-92, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10503646

RESUMEN

This study examined the ability of several childhood, school-based, social variables to correctly classify antisocial adolescents. Children (N = 314; 163 boys, 151 girls) in the 3rd-5th grade were assessed on academic and social variables (i.e., peer rejection, aggression, withdrawal, and low prosocial behavior) and followed forward for 6-7 years until the 9th and 10th grade. Adolescent antisocial outcomes included a consensus measure formed from diagnostic interviews, contact with juvenile authorities, adolescent self-report, and mother's report. The gender-differential predictive accuracy and efficacy of the early predictor domains to a consensus measure of antisocial behavior were compared with the same estimates found for adolescent self-report of antisocial behavior. Both gender and criterion-method differences were found. For girls, regardless of the measure of antisocial behavior, early academic problems were the strongest predictors of future problems. For boys' self-reported antisocial outcomes, peer rejection was the strongest independent predictor. For consensus-reported antisocial outcomes, both early fighting-anger and withdrawn behavior displayed equally strong predictive relations. For boys, the combination of early fighting-anger and disruptive and withdrawn behavior was the strongest set of predictors for the consensus measure of antisocial functioning. Predictive accuracy and efficacy estimates are discussed in terms of predictive strength as well as the cost-benefit of misidentification.


Asunto(s)
Trastorno de Personalidad Antisocial/diagnóstico , Adolescente , Trastorno de Personalidad Antisocial/psicología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Grupo Paritario , Valor Predictivo de las Pruebas , Estudios Prospectivos , Pruebas Psicológicas , Rechazo en Psicología , Reproducibilidad de los Resultados , Factores Sexuales , Alienación Social , Encuestas y Cuestionarios
13.
Addict Behav ; 11(2): 197-200, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3739804

RESUMEN

This study was a test of an operant conditioning model of cravings. The model posits that smoking or opportunity to smoke may reinforce physiological reactions to cigarette deprivation that are typically labeled as cravings. More specifically, the rate and amplitude of a physiological response (EMG activity) can be modified, and brought under stimulus control, using cigarette puffs as a reinforcer. Three adult smokers, who were deceived as to the purpose of the study, served as subjects. Three subjects were exposed to two conditions: baseline and response-contingent tone and puff. A single subject reversal design was used. Two of the three subjects showed conditioning effects with the mean level of EMG responding and rate of criterion responding in the response-contingent condition exceeding baseline levels of responding. For one of these subjects, two additional control conditions were used. Responding in the response-contingent condition was higher than in either control condition. The need for replication and extension of the present procedures are discussed.


Asunto(s)
Condicionamiento Operante , Contracción Muscular , Tabaquismo/psicología , Adulto , Condicionamiento Operante/fisiología , Electromiografía , Músculos Faciales/fisiología , Femenino , Humanos , Masculino , Refuerzo en Psicología
14.
J Exp Anal Behav ; 30(1): 47-51, 1978 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16812087

RESUMEN

Three rats were trained on a fixed-ratio escape procedure in which responding produced one of two equiprobable outcomes-a 10-second or 60-second shock-free period. Before the fixed-ratio requirement was satisfied, brief shocks were presented at irregular intervals averaging either 15 or 30 seconds. Two conditions, differing in the relationship between exteroceptive stimuli and the outcomes, were studied. In the uninformative (uncorrelated) condition, the same stimulus was presented during both outcomes. In the informative (correlated) condition, one stimulus was present during the 10-second outcome only; another stimulus was present during the 60-second outcome only. Subjects pressed faster in the uninformative condition than they did in the informative condition. The inadequacy of the information hypothesis in accounting for the findings is discussed, and an alternative hypothesis is offered.

15.
J Appl Behav Anal ; 12(2): 299-301, 1979.
Artículo en Inglés | MEDLINE | ID: mdl-16795605

RESUMEN

STUDIES IN APPLIED BEHAVIOR ANALYSIS HAVE USED TWO EXPRESSIONS OF RELIABILITY FOR HUMAN OBSERVATIONS: percentage agreement (including percentage occurrence and percentage nonoccurrence agreement) and correlational techniques (including the phi coefficient). The formal relationship between these two expressions is demonstrated, and a table for converting percentage agreement to phi, or vice-versa, is presented. It is suggested that both expressions be reported in order to communicate reliability unambiguously and to facilitate comparison of the reliabilities from different studies.

16.
Harefuah ; 143(1): 22-5, 86, 2004 Jan.
Artículo en Hebreo | MEDLINE | ID: mdl-14748283

RESUMEN

INTRODUCTION: Human spermatogenesis begins at adolescence and continues throughout life. This process includes morphologic, cytologic and biological changes, leading to the formation of mature spermatozoa. Male infertility may be caused by several reasons, including oligozoospermia at variable degrees and complete absence of mature spermatozoa. Routine spermatogram, measuring sperm counts, motility and morphology, might not provide complete information in the evaluation of these cases. This study is aimed to evaluate the possible use of flow cytometry in the identification of different sperm cell populations in sperm samples obtained from infertile men, and in determining the different cell types in various groups of infertile men. MATERIALS AND METHODS: Sperm samples from normal and infertile men (the latter were azoospermic or oligoteratozoospermic OTA) underwent flow cytometry analysis, after preparation with TNE buffer and staining with Propidium Iodide. The separation of germinal cells into different populations, according to their DNA content and chromatin condensation, was evaluated. The WINMDI (http://fac.-scripps.edu, J. Trotter) software was used for data analysis. RESULTS: Flow cytometric analysis enabled identification of several cell populations in sperm samples, including haploid, diploid and tetraploid cells. Certain cellular distribution patterns were observed in sperm samples from infertile men: mature haploid cells, diploid cells, domination of tetraploid or non-mature haploid cells, and combination of these patterns. These patterns appeared in a statistically different manner among fertile and infertile men; the median value of mature haploid cells was higher in normal men (91%, compared to 85% in the OTA group and 0% in the azoospermic men), while the median value of diploid and tetraploid cells was higher in azoospermic men (72% and 8.5% respectively, compared to only 1% and 0% in normal men). CONCLUSIONS: These findings suggest that flow cytometry of sperm samples may serve as a non-invasive tool for investigations of male infertility and for identification of appropriate candidates for interventional treatment.


Asunto(s)
Citometría de Flujo/métodos , Infertilidad Masculina , Espermatozoides/citología , Espermatozoides/patología , Humanos , Masculino , Valores de Referencia , Manejo de Especímenes/métodos , Recuento de Espermatozoides , Motilidad Espermática
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