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1.
Eur Rev Med Pharmacol Sci ; 28(11): 3771-3780, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38884512

RESUMEN

OBJECTIVE: Fractures of the proximal humerus (PHF) are commonly treated conservatively. Evidence suggests that a period of immobilization of one week or less may lead to some advantages compared to a traditional 3-4 weeks of immobilization. The purpose of this systematic review was to assess the clinical and radiological results in the case of early rehabilitation vs. delayed rehabilitation after PHF. MATERIALS AND METHODS: In July 2023, a literature search was carried out on the PubMed, MEDLINE, and Embase databases to identify all the randomized trials comparing early rehabilitation vs. delayed rehabilitation after PHF. The following data were extracted from each included study: patients' demographics, study design and level of evidence, follow-up times, treatment groups, evaluation scores adopted, and overall clinical and radiological findings. The quality of the trials was assessed using the Cochrane Risk of Bias Assessment. RESULTS: A total of 5 studies, including 378 patients and dealing with early vs. delayed rehabilitation in case of conservative treatment of PHF, were included in this study. Early rehabilitation was started within 1 week and consisted mainly of pendulum exercise and progressive passive mobilization. Early rehabilitation was associated with better pain and functional scores within the first 3 months in 3 studies. No difference in pain or function was reported at 6 months or longer follow-up, and no differences in complications rate were observed between early vs. delayed rehabilitation groups. CONCLUSIONS: This systematic review suggests that early mobilization within one week in case of conservative treatment of PHF leads to improved function recovery and reduced pain, especially in the first months of rehabilitation, without differences at longer follow-up and without increasing complications rate. Reducing immobilization time could accelerate function recovery and regaining independence in daily life activities.


Asunto(s)
Inmovilización , Fracturas del Hombro , Humanos , Fracturas del Hombro/rehabilitación , Fracturas del Hombro/terapia , Tratamiento Conservador , Factores de Tiempo
2.
J Androl ; 13(5): 409-21, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1331010

RESUMEN

It was recently demonstrated that the Leydig cell toxicant ethane dimethanesulphonate (EDS) produces multiple effects on the epididymis after a single in vivo exposure. To determine whether any of the perturbations were mediated by a direct action of the compound, we used a novel system for the coculture of epididymal epithelial cells and sperm from the caput epididymidis. This system maintains the morphologic integrity and cell polarity of the epididymal epithelial cells before and during coculture, and the sperm recovered after coculture have intact plasma and acrosomal membranes. In addition, several functions required for epididymal sperm maturation are expressed, including the secretion of protein by the epididymal epithelium, the association of secreted protein with the plasma membrane of cocultured sperm, and the acquisition of progressive motility by cocultured sperm. In vitro exposure of epididymal epithelial cells and sperm to EDS results in a significant decline in protein secretion by the epithelial cells during coculture, and in particular, a dose-dependent decline in a 36- to 38-kd protein (PI 4.0 to 4.5) and a 34- to 36-kd protein (PI 4.5 to 5.0). Moreover, these and other proteins are not recovered from the sperm membrane of cocultured sperm after EDS treatment. Finally, EDS results in a dose-dependent decline in the percentage of both motile and progressively motile sperm recovered after coculture compared with that of sperm from untreated cocultures. These effects on sperm motility were not observed when sperm were pretreated with EDS and subsequently cocultured with untreated epithelial cells. We conclude that EDS alters epididymal sperm maturation by acting directly on the epididymal epithelium to mediate changes in sperm membrane protein, and that this may subsequently alter the development of the progressive motility of sperm.


Asunto(s)
Epidídimo/efectos de los fármacos , Mesilatos/farmacología , Animales , Células Cultivadas , Epidídimo/citología , Epidídimo/metabolismo , Células Epiteliales , Masculino , Microscopía Electrónica , Proteínas/metabolismo , Ratas , Ratas Sprague-Dawley , Maduración del Esperma/efectos de los fármacos , Motilidad Espermática/efectos de los fármacos , Espermatozoides/citología , Espermatozoides/metabolismo , Espermatozoides/ultraestructura
3.
J Androl ; 18(2): 139-50, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9154508

RESUMEN

In a previous study, we found that ethane dimethanesulphonate (EDS) compromised the fertilizing ability of proximal cauda epididymal sperm from the rat within 4 days of exposure, an effect that persisted in castrated, testosterone (T)-implanted animals, establishing direct action on the epididymis. This EDS-induced reduction in fertilizing ability was highly correlated with a quantitative decrease in specific sperm protein. Here we sought to determine whether the fertility of proximal cauda epididymal sperm recovered from animals exposed to a variety of male reproductive toxicants could be predicted by assessing quantitative changes in specific sperm protein(s), or whether more common endpoints (e.g., sperm motility, sperm morphology, serum and epididymal tissue T, cauda epididymal sperm reserves) also are required to predict fertility. Intact adult male rats were dosed with EDS (25 or 50 mg/kg), chloroethylmethanesulphonate (CEMS; 12.5 or 18.75 mg/kg), or epichlorohydrin (EPI; 3 or 6 mg/kg) daily for 4 days. Castrated, T-implanted rats were dosed with hydroxyflutamide (HFLUT; 12.5 or 25 mg/kg) daily for 5 days. On day 5, proximal cauda epididymal sperm were inseminated in utero into receptive, cervically stimulated adult females, and on day 9, fertility (implants/corpora lutea) was assessed. Fertility-was decreased by the higher dose of each toxicant (P < 0.05) and also by the lower dose of EPI and HFLUT. Likewise, an acidic 22 kDa sperm protein (SP22) was decreased quantitatively (P < 0.05) in silver-stained two-dimensional gels by the higher dose of each toxicant as well as by the lower dose of EPI and HFLUT. Although sperm motility and serum T were altered by specific exposures, these endpoints were not useful in predicting fertility. In contrast, SP22 was highly correlated (P < 0.0001; r2 = 0.83) with fertility. Indeed, the amount of SP22 correctly predicted 90% and 94% of the fertile (> 50% fertility) and subfertile (< 50 fertility) animals, respectively, when discriminant analysis was performed. Thus, the amount of SP22 in a cauda epididymal sperm sample may be a useful predictor of fertility in toxicant-treated animals.


Asunto(s)
Epidídimo/efectos de los fármacos , Fertilidad , Mesilatos/toxicidad , Proteínas/análisis , Espermatozoides/fisiología , Sulfuros/toxicidad , Animales , Biomarcadores , Análisis Discriminante , Epidídimo/patología , Epidídimo/fisiología , Femenino , Inseminación Artificial , Masculino , Valor Predictivo de las Pruebas , Ratas , Ratas Sprague-Dawley , Motilidad Espermática/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Espermatozoides/patología
4.
J Androl ; 19(4): 385-93, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9733139

RESUMEN

Three nucleotide sequences encoding SP22, a protein originally identified in detergent extracts of cauda epididymal sperm, were isolated from a rat testis cDNA library. While two of these cDNA sequences differed only in their 5' untranslated regions, a third cDNA was predicted to contain an additional 13 amino acids of coding sequence. Amino acid sequences obtained following Edman degradation of purified SP22 protein and cDNA sequence data both indicated that SP22 was a member of a highly conserved and widely expressed gene family found in organisms as diverse as human and Escherichia coli. Interestingly, while a 1-kb mRNA transcript was widely expressed in somatic tissues, a unique pattern of testicular expression was observed, including the appearance of a novel 1.5-kb transcript and an increase in the abundance of the 1-kb transcript during spermatogenic cell development. Anti-SP22 peptide antiserum was shown to recognize a family of 22-kDa proteins on western blots of detergent-extracted cauda epididymal sperm protein, suggesting that multiple charge variants of SP22 coexist. Moreover, affinity-purified anti-SP22 peptide immunoglobulin localized in a highly specific manner to the anterior-ventral surface of the equatorial segment of the sperm head. This is an extremely intriguing finding as SP22 was originally shown to be highly correlated with, and predictive of, the fertilizing ability of cauda epididymal sperm. Although no conclusive function has been attributed to any members of the SP22 gene family, the localization of SP22 over a discrete region of the sperm head suggests a pivotal role in sperm-egg interactions.


Asunto(s)
Fertilidad , Proteínas/genética , Proteínas/metabolismo , Espermatozoides/metabolismo , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales , Secuencia de Bases , Northern Blotting , Western Blotting , ADN Complementario/genética , Electroforesis en Gel de Poliacrilamida , Inmunohistoquímica , Masculino , Datos de Secuencia Molecular , Ratas , Ratas Sprague-Dawley
5.
J Androl ; 16(6): 523-35, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8867601

RESUMEN

To investigate the relationship between sperm motion parameters and fertilizing ability, a model was developed to assess both of these endpoints synchronously using a toxicant that inhibits sperm motion. alpha-Chlorohydrin (ACH) was administered daily for 4 days to male hamsters at 0, 33, 49, 66, and 83 mg/kg body weight. These males were then allowed a 45-minute breeding period with untreated estrus females on the morning of day 5. One hour after breeding, sperm samples were surgically recovered from the uteri of the females for motility analysis. Six hours later, eggs were flushed from the oviducts and evaluated for fertilization. Cauda epididymal sperm were also collected from the males shortly after breeding. Proportions of motile and progressively motile sperm were manually quantified, and overall sperm velocity and the velocity of representative vigorously swimming sperm in both the uterine and epididymal samples were measured by computer-aided sperm analysis. Significant decreases in in vivo fertilization rates and epididymal sperm motion parameters were observed at 66 and 83 mg/kg ACH, whereas uterine sperm motion was adversely affected at all ACH dosages used. All sperm motion parameters except the percentage of motile sperm in the epididymis were significantly correlated with fertilization rates by both linear and logistic regression. Overall, uterine and epididymal sperm endpoints predicted fertilizing ability comparably well. Stepwise multiple linear regression gave a model containing epididymal sperm velocity (EVCL) and uterine sperm percent motility (UMOT) with an R2 value of 0.649. Stepwise multiple logistic regression gave models containing EVCL alone and EVCL and UMOT in binary (fertile/infertile) and quantal models, respectively.


Asunto(s)
Cricetinae/fisiología , Fertilidad/efectos de los fármacos , Motilidad Espermática/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Espermatozoides/fisiología , alfa-Clorhidrina/farmacología , Acetilcolina/farmacología , Animales , Peso Corporal/efectos de los fármacos , Anticonceptivos Masculinos/farmacología , Masculino , Mesocricetus , Tamaño de los Órganos/efectos de los fármacos , Reproducción , Factores de Tiempo
6.
J Androl ; 22(5): 878-90, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11545302

RESUMEN

Dibromoacetic acid (DBA) is a by-product of drinking water disinfection that alters spermatogenesis in adult male rats. To identify a mechanism by which DBA alters spermatogenesis, seminiferous tubules representing specific groups of spermatogenic stages were exposed either in vivo or in vitro, and structural and functional consequences were evaluated. Seminiferous tubules representing stages I-V, VI-VIII, and IX-XIV were isolated from testes of adult rats and cultured overnight in conditions of reduced oxygen and temperature. For in vivo exposures, seminiferous tubules were recovered from animals that had received 250 mg/kg DBA via gavage for 5 days. For in vitro exposures, 180 and 600 microM concentrations were tested; these concentrations bracket the concentration of DBA observed within the testis following in vivo exposure. Protein synthesis was evaluated by 35S-methionine labeling overnight and quantitative analysis of radiolabeled proteins in mini, 2-dimensional (2D) sodium dodecyl sulfate-polyacrylamide gel electrophoresis gels. Radio-inert cultures were processed for light and electron microscopy. Morphologicaf evaluation indicated that all spermatogenic stages of the seminiferous tubules from control animals were well maintained during the isolation and culture period. Although no treatment-related lesions were observed following in vivo exposure, histological alterations were observed at the lowest in vitro exposure. There was a significant diminution (P < .05) in the synthesis of 4 cytosolic proteins following both in vivo and in vitro exposures. Diminution in these proteins was restricted to stages I-V and IX-XIV of spermatogenesis, suggesting that proteins involved in the early stages of spermiogenesis are uniquely sensitive to DBA exposure. Because histology and protein synthesis were affected by relevant in vitro exposures, this indicates that DBA is capable of altering spermatogenesis directly.


Asunto(s)
Acetatos/química , Biosíntesis de Proteínas , Túbulos Seminíferos/metabolismo , Abastecimiento de Agua/análisis , Animales , Desinfección , Electroforesis en Gel de Poliacrilamida , Técnicas In Vitro , Masculino , Microscopía Electrónica , Ratas , Ratas Sprague-Dawley , Túbulos Seminíferos/ultraestructura
7.
Reprod Toxicol ; 11(4): 511-9, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9241671

RESUMEN

Previously we established that a 4-d exposure to chloroethylmethanesulphonate (CEMS), a chemical that significantly reduces serum testosterone (T) levels, resulted in a significant decrease in cauda epididymal sperm reserves in adult male rats while homogenization-resistant testicular spermatid numbers were unaffected. This epididymis-specific alteration occurred whether or not circulating T levels were maintained using T-filled Silastic implants. To determine whether this epididymis-specific decrease in sperm number was the result of decreased epididymal transit time, the vas deferens was ligated at its midpoint just prior to the first of 4 d of exposure to CEMS with and without T implantation. If epididymal sperm transit was accelerated due to treatment, there would be fewer sperm in the caput/corpus and more sperm in the cauda/vas of the treated animals compared to control. The number of sperm in the caput/corpus decreased significantly (P < 0.05) while the number of sperm in the cauda/vas increased significantly in both the CEMS and CEMS + T animals. Daily sperm production was unaffected, but transit time through the caput/corpus epididymidis was decreased significantly in both treatment groups. To determine if testicular fluid played a role in the epididymis-specific decline in sperm numbers, the efferent ducts were ligated at the same time the vas deferens was ligated. Again, the number of sperm in the caput/corpus decreased significantly with treatment while there was a reciprocal increase in the number of cauda/vas sperm relative to controls. Finally, to determine whether an androgen-mediated process might be involved, the known antiandrogen hydroxyflutamide (HFLUT) was given to castrated, T-implanted animals in which the fertilizing ability of epididymidal sperm is maintained over 4 days. Once again, the number of sperm in the caput/corpus decreased significantly while there was a reciprocal increase in cauda/vas sperm. A quantitative evaluation of the protein profile in homogenates of the caput/corpus epididymidis revealed treatment-related diminutions in two proteins CC9 (M(r) = 42 kDa, pI = 4.2) and CC34 (M(r) = 35 kDa, pI = 5.5), and the level of each of these proteins in the caput/corpus was significantly correlated with the decrease in caput/corpus sperm number. Thus, both CEMS and HFLUT accelerate sperm transit through the proximal segment of the epididymis; and, while this effect is not dependent on the testis, it may involve a lesion in androgen-dependent epididymal function.


Asunto(s)
Epidídimo/efectos de los fármacos , Proteínas/análisis , Espermatozoides/efectos de los fármacos , Testosterona/fisiología , Animales , Epidídimo/química , Masculino , Ratas , Ratas Sprague-Dawley
8.
Reprod Toxicol ; 5(5): 449-58, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1806155

RESUMEN

The objective of these studies was to optimize conditions for computer-assisted sperm analysis (CASA) of rat epididymal spermatozoa. Methodologic issues addressed include sample collection technique, sampling region within the epididymis, type of diluent medium used, and sample chamber depth. In addition, sources of variation were identified and accuracy of the analysis was examined. All samples in this report were analyzed using a Hamilton Thorn Motility Analyzer (HTM-2000; Hamilton Thorn Research, Danvers, MA). We found that allowing the sperm to swim out from cuts made in the distal cauda epididymidis yielded samples with percentages of motile sperm 60% higher than samples collected using an aspiration method. Furthermore, sperm isolated from the distal cauda epididymidis exhibited slightly but significantly greater percentages of motile sperm and swimming speeds than sperm isolated from the proximal cauda epididymidis. Of the four motility media examined, all maintained a high percentage of motile sperm over an hour-long incubation period, but Medium 199 and modified Hanks' Balanced Salt supported substantially greater sperm velocity than Dulbecco's Phosphate Buffered Saline (with Ca++ and Mg++), with or without glucose. Motility and velocity endpoints were comparable in 200-, 100-, or 40-micron deep chambers, but significantly lower in 20-micron-deep chambers. Since these and presumably other variables in the preparation and analysis of rat sperm do influence the assessed motility endpoints, it is important to standardize these methods and to consider these issues when interpreting CASA data.


Asunto(s)
Ratas/fisiología , Motilidad Espermática/fisiología , Animales , Computadores , Medios de Cultivo , Difusión , Epidídimo/citología , Técnicas In Vitro , Masculino , Estándares de Referencia
9.
Reprod Toxicol ; 5(1): 39-44, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1666965

RESUMEN

Sperm motion analysis following exposure to a reproductive toxicant is one means of evaluating the functional integrity of the testis and epididymis. In this study we sought to determine whether the method used to collect sperm from the proximal cauda epididymidis, where sperm are not completely mature, has a significant influence on sperm motion parameters. Two methods of collecting rat sperm for motion analysis were used: one based on an aspiration technique selected from the literature; the other, a new approach based on diffusion of sperm from the epididymal tubule. The two methods were tested for sensitivity to effects on sperm motility parameters 4 days after a single exposure to ethane dimethanesulphonate (EDS). Since EDS is known to decrease serum testosterone (T), an additional group of rats received T-filled implants just prior to dosing to determine if the decrease in serum T alone had an effect on sperm motility. The results of the study yielded strikingly different interpretations of the effect of a 65 mg/kg BW dose of EDS on the motility of sperm taken from the proximal cauda epididymidis. Sperm collected by "aspiration" showed no significant decrease in the percentage of motile or progressively motile sperm compared to vehicle-treated animals. On the contrary, sperm collected by "diffusion" showed large, significant decreases in the percentages of both motile and progressively motile sperm. This difference was due largely to lower percentages of motile and progressively motile sperm in control sperm samples collected by aspiration. Similarly, the motion parameters of sperm collected by the aspiration method were unaffected by EDS/T treatment.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Mesilatos/toxicidad , Manejo de Especímenes/métodos , Motilidad Espermática/efectos de los fármacos , Animales , Difusión , Procesamiento de Imagen Asistido por Computador , Masculino , Ratas , Ratas Endogámicas , Succión , Grabación de Cinta de Video
10.
Reprod Toxicol ; 6(6): 491-505, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1288759

RESUMEN

Multiple endpoints of spermatotoxicity in short duration tests (1-5 days exposure; 2.5-week assay interval) were investigated in a number of chemicals reported to produce minimal to severe reproductive effects when administered subchronically. Six of these chemicals (boric acid, dinoseb, 2,5-hexanedione, methoxychlor, metronidazole, ornidazole) produced substantial spermatotoxicity after 1 to 5 doses. Spermatotoxic effects of chlordimeform were equivocal while p,p'-DDT, n-hexane, and sodium chlorite were judged negative. Four chemicals with known acute effects (benomyl, busulfan, ethylene glycol monomethyl ether, nitrobenzene) elicited expected histopathologic responses after a single dose. Testicular histology, testicular sperm head counts, cauda sperm counts, sperm morphology, and sperm velocity proved to be the most toxicologically sensitive endpoints in one or more of the studies, but histopathology of the testis and epididymis was the most consistent indicator of reproductive damage. The percentage of motile sperm and sperm concentration in the epididymal fluid were the least sensitive measurements. The data suggested that most chemicals with the potential to produce moderate to severe sperm damage are detectable with a short duration test. Complementary multiple endpoints enhanced the interpretation of results, often identified cellular targets, and provided insight on possible mechanisms. Specific responses were often similar to specific effects reported for subchronic exposures. A short duration test could be of value as a screen in structure-activity studies or to set priorities for chemicals requiring further evaluation. As a supplement to breeding studies, the data generated in the short test could also be used to enhance the design and interpretation of the longer tests.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Reproducción/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Animales , Epidídimo/efectos de los fármacos , Epidídimo/patología , Masculino , Preparaciones Farmacéuticas/administración & dosificación , Ratas , Ratas Sprague-Dawley , Testículo/efectos de los fármacos , Testículo/patología
11.
Reprod Toxicol ; 11(5): 681-8, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9311576

RESUMEN

The testicular toxicity of dichloroacetic acid (DCA), a disinfection byproduct of drinking water, was evaluated in adult male rats given both single and multiple (up to 14 d) oral doses. Delayed spermiation and altered resorption of residual bodies were observed in rats given single doses of 1500 and 3000 mg/kg; these effects persisted to varying degrees on post-treatment days 2, 14, and 28. Delayed spermiation and formation of atypical residual bodies also were observed on days 2, 5, 9, and 14 in rats dosed daily with 1440, 480, 160, and 54 mg/kg. Distorted sperm heads and acrosomes were observed in step 15 spermatids after 14 doses of 480 and 1440 mg/kg. Decreases in the percentage of motile sperm occurred after 9 doses of 480 and 1440 mg/kg and 14 doses of 160 mg/kg. Increased numbers of fused epididymal sperm were observed on days 5, 9, and 14 in rats dosed with 1440, 480, and 160 mg/kg, respectively; other morphologic abnormalities occurred at 160 mg/kg and higher. On day 14, a significant decrease in epididymis weight was observed at 480 and 1440 mg/kg, and epididymal sperm count was decreased at 160 mg/kg and higher. These studies demonstrate that the testicular toxicity induced by DCA are similar to those produced by the analogue, dibromoacetic acid. However, the testicular toxicity of DCA is less severe at equal molar concentrations. Moreover, the DCA-induced testicular lesions occur with greater potency as the duration of dosing increases, indicating the importance of using low-dose subchronic exposures to assess the health risk of prevalent disinfection byproducts.


Asunto(s)
Acetatos/toxicidad , Ácido Dicloroacético/toxicidad , Espermatozoides/efectos de los fármacos , Testículo/efectos de los fármacos , Administración Oral , Animales , Peso Corporal/efectos de los fármacos , Epidídimo/efectos de los fármacos , Epidídimo/patología , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Reproducción/efectos de los fármacos , Recuento de Espermatozoides/efectos de los fármacos , Motilidad Espermática/efectos de los fármacos , Espermatozoides/patología , Testículo/patología , Testosterona/sangre
12.
Reprod Toxicol ; 9(6): 571-8, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8597653

RESUMEN

There is increasing epidemiologic interest in the role drinking water disinfection byproducts (DBPs) may play in adverse reproductive outcomes such as inability to conceive, spontaneous abortion, and low birth weight. Although dozens of DBPs already have been identified, only a few studies have attempted to determine whether DBPs alter male reproductive parameters such as testicular and epididymal histology, testicular and epididymal sperm numbers, and epididymal sperm morphology and motility in laboratory animals. In these studies, alterations in epididymal sperm motility seemed to be predictive of more generalized toxicity of the male reproductive system. Because there is a need to prioritize DBPs for thorough reproductive and developmental toxicity testing, preliminary screening for the potential of DBPs to alter reproductive function seems warranted. Here, we elected to examine only cauda epididymal sperm motion parameters and testicular and epididymal histopathology. The effects of exposure to two commonly occurring DBPs, bromodichloromethane (BDCM) and chloral hydrate (CH), via drinking water were evaluated in F344 rats at an interim (52 week) necropsy during cancer bioassay studies. Exposure to 22 and 39 mg/kg BDCM and 55 and 188 mg/kg CH did not produce any systemic toxicity. Histopathologic evaluation revealed no gross lesions in the reproductive organs, and no tumors were detected in any tissues. In contrast, exposure to 39 mg/kg BDCM significantly decreased the mean straight-line, average path, and curvilinear velocities of sperm recovered from the cauda epididymidis. This BDCM exposure shifted the average path velocity distribution to a lower modal velocity range. Exposure to 188 mg/kg CH significantly decreased both the percentage of motile and progressively motile sperm. This CH exposure shifted the straight-line velocity distribution to a lower modal velocity range. These are the first reproductive toxicity data from exposure to BDCM and CH. The observed effects on sperm motion occurred in the absence of carcinogenesis. Because the effects of BDCM on sperm motility occurred at a lower exposure than that of other DBPs that compromise sperm motility, a thorough reproductive evaluation now is underway.


Asunto(s)
Hidrato de Cloral/toxicidad , Desinfectantes/toxicidad , Hidrocarburos Halogenados/toxicidad , Motilidad Espermática/efectos de los fármacos , Testículo/efectos de los fármacos , Abastecimiento de Agua/normas , Animales , Masculino , Ratas , Ratas Endogámicas F344 , Trihalometanos
13.
Reprod Toxicol ; 11(1): 47-56, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9138633

RESUMEN

The present report details histopathologic changes in the testis and epididymis of rats gavaged daily for 2 to 79 d with a by-product of water disinfection, dibromoacetic acid (DBAA). On treatment day 2 abnormal retention of Step 19 spermatids was observed in animals given the highest dosage of 250 mg/kg. Additional changes on day 5 included the fusion of mature spermatids and the presence of atypical residual bodies (ARB) in the epithelium and lumen of Stage X-XII seminiferous tubules. By day 9, ARB were seen in most stages of the seminiferous epithelial cycle and in the caput epididymidis. On day 16 distorted sperm heads were recognized in Step 12, and older spermatids, and luminal cytoplasmic debris was found throughout the epididymis. On day 31, there was vacuolation of the Sertoli cell cytoplasm, extensive retention of Step 19 spermatids near the lumen of Stage IX and X tubules, and vesiculation of the acrosomes of late spermatids. Marked atrophy of the seminiferous tubules was present 6 months after 42 doses of 250 mg/kg. ARB and retention of Step 19 spermatids were observed after 31 and 79 doses of 50 mg/kg and increased retention of Step 19 spermatids was seen in several rats dosed with 10 mg/kg. No abnormalities were detected at the dosage of 2 mg/kg. The changes suggest that the testicular effects of DBAA are sequelae to structural and/or functional changes in the Sertoli cell.


Asunto(s)
Acetatos/toxicidad , Testículo/efectos de los fármacos , Testículo/patología , Animales , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Masculino , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley
14.
Reprod Toxicol ; 8(3): 251-9, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8075514

RESUMEN

Halogenated acetic acids are major disinfection by-products of water chlorination and ozonation. Limited data in experimental animals indicate that repeated doses of dichloroacetic acid (DCA) or single doses of dibromoacetic acid (DBAA) cause testicular damage. In the present study, spermatotoxic effects were investigated in rats given oral doses of 0, 10, 30, 90, or 270 mg DBAA/kg/day for 14 days. In rats dosed with 270 mg/kg/day, there were marked effects on epididymal sperm motility and morphology including the flagellar fusion of 2 or more sperm. Testis weight, epididymis weight, and testicular sperm head counts were mildly reduced relative to control, whereas epididymal sperm counts were substantially decreased. Histologic changes in the testis included retention of Step 19 spermatids in Stages IX to XII, abnormal development of late spermatids, and the formation of atypical structures resembling residual bodies that were observed predominantly in Stages X to XIV and I of the cycle of the seminiferous epithelium. At the dosage of 90 mg/kg/day, effects on spermiation, spermatid development, epididymal sperm counts, sperm motility, and sperm morphology were less severe than at the higher dosage. Reduced caput sperm counts and mild effects on spermiation also occurred at 30 and 10 mg/kg/day. These studies indicate that subchronic exposure to DBAA has the potential to affect reproductive outcome in the rat. Compared to previous studies of DCA (12), DBAA, on a molar basis, appears to be a stronger testicular toxicant than the dichloro analogue.


Asunto(s)
Acetatos/toxicidad , Reproducción/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Masculino , Ratas , Ratas Sprague-Dawley , Espermatozoides/patología , Testículo/efectos de los fármacos , Testículo/patología , Testículo/ultraestructura
15.
Rev Neurol ; 31(1): 49-52, 2000.
Artículo en Español | MEDLINE | ID: mdl-10948584

RESUMEN

INTRODUCTION: There is evidence that cancer is the result of an accumulation of genetic alterations which lead to uncontrolled cell proliferation with loss of the processes of cell differentiation. DEVELOPMENT: In this review we try to explain the molecular alterations which occur in the anaplastic degeneration of astrocyte gliomas, conditioned by loss of genetic material on chromosomes 10 and 17, mutation of gene p53, amplification of the receptor of the epidermic growth factor, translocations of chromosomes 9p, 13q, 19q and 22q amongst others. On clinical and molecular studies two basic genetic pathways in the development of glioblastoma multiform have been identified. One of progressive degeneration of an astrocytoma of low-grade malignancy and the other from normal neuroglial cells such as a glioblastoma multiform de novo. CONCLUSIONS: The oncogens and tumor suppressive genes are the basis of the lack of control and abnormal cellular proliferation. An understanding of the changes which they cause will in future permit the application of new therapeutic options in patients with malignant astroglial neoplasias.


Asunto(s)
Neoplasias Encefálicas/patología , Glioma/patología , Astrocitos/patología , Neoplasias Encefálicas/genética , Diferenciación Celular/fisiología , Movimiento Celular/fisiología , Cromosomas Humanos Par 10/genética , Cromosomas Humanos Par 13/genética , Cromosomas Humanos Par 17/genética , Cromosomas Humanos Par 19/genética , Cromosomas Humanos Par 22/genética , Cromosomas Humanos Par 9/genética , Genes Supresores de Tumor/genética , Genes p53/genética , Glioma/genética , Humanos , Neuroglía/patología , Mutación Puntual/genética
16.
Rev Neurol ; 31(12): 1180-3, 2000.
Artículo en Español | MEDLINE | ID: mdl-11205555

RESUMEN

INTRODUCTION: Gliomas make up approximately 50% of the primary brain tumors of the central nervous system in adults. Astrocytes from between 70 and 75% of these tumors. Historically grading these has been very controversial, in spite of its importance for prognosis and planning treatment. DEVELOPMENT: We have reviewed existing proposals for the classification of astroglial neoplasias, from the initial studies to the latest classification by the World Health Organization. All have pursued the objective of finding the histopathological grade of the neoplasm to relate it to survival and predict prognosis. CONCLUSION: Further knowledge of these tumors is the aim of professionals and others interested in the subject, in the difficult course of finding better and more efficient treatment for these patients.


Asunto(s)
Astrocitoma/clasificación , Neoplasias Encefálicas/clasificación , Adulto , Astrocitoma/química , Astrocitoma/genética , Astrocitoma/patología , Biomarcadores de Tumor/análisis , Encéfalo/patología , Neoplasias Encefálicas/química , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Recuento de Células , Niño , Glioblastoma/química , Glioblastoma/genética , Glioblastoma/patología , Humanos , Índice Mitótico , Organización Mundial de la Salud
17.
Toxicol Appl Pharmacol ; 105(2): 271-87, 1990 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-2171157

RESUMEN

Ethane dimethanesulfonate (EDS), a Leydig cell toxicant which results in transient infertility, was used in a 4 day postexposure experimental protocol designed to identify any effects this compound might exert on the epididymis. The techniques of efferent duct ligation and testosterone (T) implantation were used to negate the role of testicular effects on the epididymal parameters. Numerous evaluations were performed including light and electron microscopy, computer assisted sperm motion analyses, and electrophoresis of sperm membrane proteins. EDS was shown to affect the epididymis in a dose-dependent fashion. The action of EDS on the epididymis is in part due to Leydig cell cytotoxicity and the resulting decrease in circulating androgen since T implantation prevented some of the changes in sperm proteins and motility. However, neither efferent duct ligation nor T implantation prevented the formation of sperm granulomas in the caput epididymidis, the distinct morphological alterations of the corpus epididymidis, the modification of certain sperm membrane proteins, or the decrease in the progressive motility and velocity of sperm following EDS treatment. Although we cannot prove these effects of EDS are due to a direct action on the epididymis, it is now clear that EDS has a distinct action on the epididymis which is unrelated to circulating T or testicular fluid.


Asunto(s)
Epidídimo/patología , Mesilatos/toxicidad , Testículo/patología , Animales , Epidídimo/efectos de los fármacos , Epidídimo/ultraestructura , Células Intersticiales del Testículo/efectos de los fármacos , Células Intersticiales del Testículo/patología , Masculino , Microscopía Electrónica , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Endogámicas , Valores de Referencia , Motilidad Espermática/efectos de los fármacos , Espermátides/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Espermatozoides/metabolismo , Espermatozoides/patología , Testículo/efectos de los fármacos
18.
Fundam Appl Toxicol ; 15(3): 597-606, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2258022

RESUMEN

The effect of inhaled epichlorohydrin on rat sperm motility characteristics was evaluated. Male F-344 rats were exposed to 100 ppm epichlorhydrin via inhalation for 4 hr in the morning of Day 0 and killed immediately and on Days 1, 2, 6, and 14 postexposure. Videotapes of cauda epididymal sperm were analyzed (300-350 sperm/sample) with a Hamilton Thorn motility analyzer (HTM-2000, Hamilton Thorn Research, Danvers, MA). Epichlorohydrin did not affect the percentage of motile sperm at any time. However, transient changes in sperm velocity were found. On Day 1 postexposure mean progressive (straight line) and mean path (smoothed curvilinear) velocity were significantly decreased to 80 and 85% of control, respectively. The progressive velocities of sperm from both control and treated rats were normally distributed, indicating a general effect of epichlorohydrin on all sperm as opposed to a more severe effect on a specific sperm subpopulation. Sperm velocity was not significantly affected at later times. Other endpoints (testis and epididymis weights, testicular spermatid counts, and cauda epididymal sperm reserves) were unaltered by epichlorohydrin. Thus, inhaled epichlorohydrin at 100 ppm produced specific, transient decreases in rat sperm velocity. Furthermore, computer-assisted sperm analysis was able to detect these relatively subtle, toxicant-induced changes in rat sperm velocity, demonstrating the utility of this technology in reproductive toxicology studies.


Asunto(s)
Epiclorhidrina/toxicidad , Motilidad Espermática/efectos de los fármacos , Administración por Inhalación , Animales , Computadores , Interpretación Estadística de Datos , Epiclorhidrina/administración & dosificación , Riñón/efectos de los fármacos , Hígado/efectos de los fármacos , Masculino , Ratas , Ratas Endogámicas F344
19.
Fundam Appl Toxicol ; 21(3): 298-307, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8258383

RESUMEN

To optimize the Hamilton-Thorn Motility Analyzer (HTM; Hamilton-Thorn Research, Beverly, MA) for use in reproductive toxicology studies with rat spermatozoa, the accuracy and precision of the instrument were assessed under a variety of instrument settings. Videotapes of both fast- and slow-swimming sperm were analyzed repeatedly to obtain data across a range of sperm velocities as might be encountered as a consequence of exposure to reproductive toxicants. Acquisition rates were varied across the HTM menu choices (30, 19, 10, or 7 frames/sec) as were the number of frames analyzed (5 to 20) at each framing rate. For fast-swimming samples (mean straight-line velocity (VSL) approximately 130 microns/sec) generally good agreement between computer-assisted sperm analysis (CASA) and manually obtained data was found for percentage of motile sperm and straight-line velocity; i.e., CASA values were within 10% of manual values for most frame/rate combinations. The accuracy of these measures held true over a wide range of sperm concentrations and percentage motilities. However, CASA measures were less accurate for sperm samples of lower velocities (mean VSL approximately 50 microns/sec and mean VSL approximately 30 microns/sec) in that the velocity of very slow sperm was overestimated (particularly at 30 frames/sec). A soft-ware change (6.5R) and performing analyses at 19 instead of 30 frames/sec improved straight-line accuracy for the slow sperm and enhanced the discrimination between fast (presumably control) and slow (presumably treated) sperm samples. These data show that this motility analyzer could be successfully configured to evaluate rodent sperm samples. The use of such CASA systems in toxicology studies will provide valuable information that may improve human reproductive risk assessment.


Asunto(s)
Motilidad Espermática/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Toxicología/métodos , Animales , Computadores , Masculino , Fisiología/instrumentación , Ratas , Ratas Sprague-Dawley , Programas Informáticos , Recuento de Espermatozoides , Grabación en Video
20.
Fundam Appl Toxicol ; 22(3): 422-30, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8050637

RESUMEN

Chlorine and bromine can react with natural organic substances in source waters to form haloacetic acids, major disinfection by-products of water chlorination. Several toxic effects including testicular damage have been attributed to the chloroacetic acids but little information is available on the bromine analogues. In this report we present the results of acute toxicity and acute spermatotoxicity studies of monobromoacetic acid (MBAA) and dibromoacetic acid (DBAA). In adult male rats the acute oral toxicity of MBAA was 10-fold that of DBAA (LD50 177 vs 1737 mg/kg). No reproductive-related endpoints were affected in rats given a single dose of 100 mg MBAA/kg or 14 daily doses of 25 mg MBAA/kg/day. In rats dosed with DBAA, serum testosterone fell to 17% of control 2 days after a single dose of 1250 mg/kg but returned to control levels by Day 14. Marked effects on sperm motion were seen on post-treatment Days 14 and 28. Degenerative flagellar changes in cauda sperm were present on Day 14 while abnormal sperm head shapes and flagellar degeneration were observed in both caput and cauda sperm on Day 28. Histopathology indicated altered spermiation at all time-points as evidenced by retention of Step 19 spermatids beyond Stage VIII of the cycle of the seminiferous epithelium. Disorganization, distortion, and degeneration of late spermatids were also observed. On Day 14 structures resembling residual bodies were rarely seen in the testis but were numerous in the epididymis. Caput sperm counts were decreased on Day 2 and cauda sperm counts were decreased on Days 14 and 28.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Acetatos/toxicidad , Espermatogénesis/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Peso Corporal/efectos de los fármacos , Dosificación Letal Mediana , Masculino , Tamaño de los Órganos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Túbulos Seminíferos/citología , Túbulos Seminíferos/efectos de los fármacos , Recuento de Espermatozoides/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Espermatozoides/ultraestructura , Testículo/patología , Testosterona/sangre
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