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1.
Theriogenology ; 161: 108-119, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33307428

RESUMEN

Contemporary systems for oocyte retrieval and culture of both cattle and human embryos are suboptimal with respect to pregnancy outcomes following transfer. In humans, chromosome abnormalities are the leading cause of early pregnancy loss in assisted reproduction. Consequently, pre-implantation genetic testing for aneuploidy (PGT-A) is widespread and there is considerable interest in its application to identify suitable cattle IVP embryos for transfer. Here we report on the nature and extent of chromosomal abnormalities following transvaginal follicular aspiration (OPU) and IVP in cattle. Nine sexually mature Holstein heifers underwent nine sequential cycles of OPU-IVP (six non-stimulated and three stimulated cycles), generating 459 blastocysts from 783 oocytes. We adopted a SNP-array approach normally employed in genomic evaluations but reanalysed (Turner et al., 2019; Theriogenology125: 249) to detect levels of meiotic aneuploidy. Specifically, we asked whether ovarian stimulation increased the level of aneuploidy in either trophectoderm (TE) or inner-cell mass (ICM) lineages of blastocysts generated from OPU-IVP cycles. The proportion of Day 8 blastocysts of inseminated was greater (P < 0.001) for stimulated than non-stimulated cycles (0.712 ± 0.0288 vs. 0.466 ± 0.0360), but the overall proportion aneuploidy was similar for both groups (0.241 ± 0.0231). Most abnormalities consisted of meiotic trisomies. Twenty in vivo derived blastocysts recovered from the same donors were all euploid, thus indicating that 24 h of maturation is primarily responsible for aneuploidy induction. Chromosomal errors in OPU-IVP blastocysts decreased (P < 0.001) proportionately as stage/grade improved (from 0.373 for expanded Grade 2 to 0.128 for hatching Grade 1 blastocysts). Importantly, there was a high degree of concordance in the incidence of aneuploidy between TE and ICM lineages. Proportionately, 0.94 were "perfectly concordant" (i.e. identical result in both); 0.01 were imperfectly concordant (differing abnormalities detected); 0.05 were discordant; of which 0.03 detected a potentially lethal TE abnormality (false positives), leaving only 0.02 false negatives. These data support the use of TE biopsies for PGT-A in embryos undergoing genomic evaluation in cattle breeding. Finally, we report chromosome-specific errors and a high degree of variability in the incidence of aneuploidy between donors, suggesting a genetic contribution that merits further investigation.


Asunto(s)
Enfermedades de los Bovinos , Diagnóstico Preimplantación , Aborto Veterinario , Aneuploidia , Animales , Blastocisto , Bovinos/genética , Cromosomas , Femenino , Inducción de la Ovulación/veterinaria , Embarazo
2.
Ann Trop Med Parasitol ; 105(1): 1-11, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21294944

RESUMEN

Hendra virus (HeV) was first isolated in 1994, from a disease outbreak involving at least 21 horses and two humans in the Brisbane suburb of Hendra, Australia. The affected horses and humans all developed a severe but unidentified respiratory disease that resulted in the deaths of one of the human cases and the deaths or putting down of 14 of the horses. The virus, isolated by culture from a horse and the kidney of the fatal human case, was initially characterised as a new member of the genus Morbillivirus in the family Paramyxoviridae. Comparative sequence analysis of part of the matrix protein gene of the virus and the discovery that the virus had an exceptionally large genome subsequently led to HeV being assigned to a new genus, Henipavirus, along with Nipah virus (a newly emergent virus in pigs). The regular outbreaks of HeV-related disease that have occurred in Australia since 1994 have all been characterised by acute respiratory and neurological manifestations, with high levels of morbidity and mortality in the affected horses and humans. The modes of transmission of HeV remain largely unknown. Although fruit bats have been identified as natural hosts of the virus, direct bat-horse, bat-human or human-human transmission has not been reported. Human infection can occur via exposure to infectious urine, saliva or nasopharyngeal fluid from horses. The treatment options and efficacy are very limited and no vaccine exists. Reports on the outbreaks of HeV in Australia are collated in this review and the available data on the biology, transmission and detection of the pathogen are summarized and discussed.


Asunto(s)
Quirópteros/virología , Brotes de Enfermedades , Virus Hendra/patogenicidad , Infecciones por Henipavirus/epidemiología , Infecciones por Henipavirus/virología , Enfermedades de los Caballos/virología , Animales , Australia/epidemiología , Brotes de Enfermedades/estadística & datos numéricos , Virus Hendra/genética , Virus Hendra/aislamiento & purificación , Infecciones por Henipavirus/mortalidad , Infecciones por Henipavirus/transmisión , Enfermedades de los Caballos/epidemiología , Enfermedades de los Caballos/transmisión , Caballos , Humanos , Inmunohistoquímica , Virus Nipah/patogenicidad , Zoonosis/epidemiología , Zoonosis/virología
3.
Am J Trop Med Hyg ; 65(6): 747-53, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11791969

RESUMEN

In mid-January 2000, the reappearance of Japanese encephalitis (JE) virus activity in the Australasian region was first demonstrated by the isolation of JE virus from 3 sentinel pigs on Badu Island in the Torres Strait. Further evidence of JE virus activity was revealed through the isolation of JE virus from Culex gelidus mosquitoes collected on Badu Island and the detection of specific JE virus neutralizing antibodies in 3 pigs from Saint Pauls community on Moa Island. Nucleotide sequencing and phylogenetic analyses of the premembrane and envelope genes were performed which showed that both the pig and mosquito JE virus isolates (TS00 and TS4152, respectively) clustered in genotype I, along with northern Thai, Cambodian, and Korean isolates. All previous Australasian JE virus isolates belong to genotype II, along with Malaysian and Indonesian isolates. Therefore, for the first time, the appearance and transmission of a second genotype of JE virus in the Australasian region has been demonstrated.


Asunto(s)
Virus de la Encefalitis Japonesa (Especie)/genética , Encefalitis Japonesa/epidemiología , Animales , Culex , Cartilla de ADN , Virus de la Encefalitis Japonesa (Especie)/aislamiento & purificación , Genotipo , Humanos , Filogenia , Queensland/epidemiología , ARN Viral/genética , ARN Viral/aislamiento & purificación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Vigilancia de Guardia , Porcinos
6.
J Glaucoma ; 7(5): 319-28, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9786561

RESUMEN

PURPOSE: The effect of contact transscleral diode cyclophotocoagulation (TDC) on intraocular pressure (IOP) and its safety was determined in eyes with intractable glaucoma. METHODS: The charts of 41 consecutive patients (43 eyes) who underwent the laser procedure were reviewed. After surgery, data were collected from chart entries at I hour, 1 day, 4 to 6 weeks, 4 to 6 months, and at the final visit (6-24 months). Mean differences in IOP before and after treatment were compared using the paired Student t test. Associated complications also were assessed. RESULTS: The mean +/- standard deviation follow-up period was 11.9+/-5.3 months (range, 6-24 months). One patient who died after 1 month of follow-up and another patient with neovascular glaucoma who underwent an anterior chamber washout 1 week after laser to treat an uncontrolled IOP spike were excluded from the study. Repeat treatment was done in 12 (28%) eyes. At each follow-up visit postoperatively, a significant reduction from preoperative IOP was obtained (mean reduction of 50% at the final visit). At the final visit, 64% of patients achieved an IOP of <22 mmHg and a reduction of > or =20%. An IOP spike occurred in three (7%) eyes. Long-term complications included loss of vision (> or =2 lines) in eight (22%) patients, corneal decompensation in one (2%), phthisis bulbi in one (2%), and corneal graft rejection in one (2%). CONCLUSION: Although effective IOP reduction was demonstrated in eyes with intractable glaucoma after TDC, a significant proportion (26%) of eyes had severe long-term complications.


Asunto(s)
Cuerpo Ciliar/cirugía , Glaucoma/cirugía , Presión Intraocular , Coagulación con Láser , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Estudios de Seguimiento , Glaucoma/tratamiento farmacológico , Glaucoma/etiología , Humanos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos , Seguridad , Esclerótica , Resultado del Tratamiento , Agudeza Visual
7.
J Dev Behav Pediatr ; 18(5): 304-13, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9349973

RESUMEN

In a prospective study of 137 children (47 with cystic fibrosis, 48 with congenital heart disease, 42 with no chronic illness), four domains were examined as predictors of parent-reported behavioral problems, particularly internalizing problems, at 4 years of age: child health, child temperament, parent-child relationships, and family environment. Family environment, as measured by the Parenting Stress Index at 1,2, and 3 years, was the most powerful predictor. This suggests that this index is useful as an early screen for children at risk for behavioral problems and that a reduction of parenting stress is an appropriate target of preventive interventions.


Asunto(s)
Trastornos de la Conducta Infantil/diagnóstico , Desarrollo Infantil , Fibrosis Quística/complicaciones , Salud de la Familia , Cardiopatías Congénitas/complicaciones , Adulto , Estudios de Casos y Controles , Preescolar , Enfermedad Crónica , Fibrosis Quística/psicología , Femenino , Predicción , Estado de Salud , Cardiopatías Congénitas/psicología , Humanos , Masculino , Oportunidad Relativa , Relaciones Padres-Hijo , Estudios Prospectivos , Análisis de Regresión , Índice de Severidad de la Enfermedad , Temperamento
8.
Ophthalmic Surg Lasers ; 28(3): 241-3, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9076801

RESUMEN

Hypotony maculopathy may arise after glaucoma filtering surgery. This can be treated by inducing inflammation and scarring within the filter, with the aim of increasing intraocular pressure (IOP) and promoting resolution of maculopathy. Cataract extraction can promote such inflammation. Phacoemulsification with posterior chamber intraocular lens (PC IOL) implantation was performed in two consecutive patients with postfiltration hypotony maculopathy and preexisting cataracts. After cataract extraction, improvement of IOP, visual acuity, maculopathy, and metamorphopsia occurred in both patients. Cataract extraction can be beneficial in the management of postfiltration hypotony maculopathy.


Asunto(s)
Extracción de Catarata , Mácula Lútea/cirugía , Hipotensión Ocular/cirugía , Enfermedades de la Retina/cirugía , Femenino , Cirugía Filtrante/efectos adversos , Estudios de Seguimiento , Glaucoma/cirugía , Humanos , Presión Intraocular , Mácula Lútea/patología , Masculino , Persona de Mediana Edad , Hipotensión Ocular/complicaciones , Hipotensión Ocular/fisiopatología , Enfermedades de la Retina/etiología , Enfermedades de la Retina/fisiopatología , Agudeza Visual
9.
Biomed Sci Instrum ; 33: 59-64, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9731336

RESUMEN

This paper provides the results from an experimental study intended to assess airbag impact to the orbit. Twenty-seven airbags were deployed onto an instrumented Hybrid III headform. Seven different types of airbags were used that included tethered and nontethered, light to heavy nylon weaves, and different coating types. The airbags were deployed via a pneumatic deployment system. Seven individual force transducers, each having a 2.25 cm2 contact area, were placed on the right orbital region to evaluate the force patterns. The midpoint of the two ocular regions of the headform was positioned 12.5 cm above and 15.0 cm away from the center of the airbag, a position determined from previous airbag deployments to yield the highest leading edge velocity. The average maximum force per sensor ranged from 15.4 N to 63.6 N, and peak pressure ranged from 68 kPa to 282 kPa. The upper center of the orbit presented the highest values while the center of the orbit recorded the lowest values, a comparison that was proven to be statistically significant. For this configuration, the maximum force on the ocular region was found to be independent of the presence of a tether or the maximum internal airbag pressure.


Asunto(s)
Airbags/efectos adversos , Lesiones Oculares/fisiopatología , Fenómenos Biomecánicos , Lesiones Oculares/etiología , Humanos , Modelos Anatómicos
10.
Biomed Sci Instrum ; 33: 106-11, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9731344

RESUMEN

In an attempt to investigate eye injuries from airbags, a set of experiments was performed that involved the deployment of several types of airbags onto thirteen unembalmed, previously frozen cadaver heads. The airbags differed in the material, coating, presence of a tether, and folding pattern, and were deployed via a pneumatic deployment system. The eyes were impacted in situ after being repressureized with saline injected through a 30-gauge needle. Injury determination was achieved by ophthalmic ultrasound imaging, staining with fluorescein dye, and dissection. All twenty-six eyes revealed detached retinas, as shown by the ultrasound, before impact as a result of decaying tissue and the freezing process. High speed video and film were used to capture the events. The impact velocities of the airbags were recorded from the digitized film at the first contact location with the eye and ranged from 30 m/s to 66 m/s. Eyeglasses were placed on four of the specimens, and the presence of eyeglasses seemed to provide protection to the eye because of the lack of contact between the airbag and ocular region. Minimal ocular damage was recorded for all experiments.


Asunto(s)
Airbags/efectos adversos , Lesiones Oculares/fisiopatología , Fenómenos Biomecánicos , Lesiones Oculares/etiología , Lesiones Oculares/patología , Anteojos , Humanos , Técnicas In Vitro
12.
Ophthalmic Surg Lasers ; 28(12): 986-91, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9427985

RESUMEN

BACKGROUND AND OBJECTIVES: Trabeculectomies usually fail early (< 21 days) or late (> 6 months) when no antifibrotic agent is used. Failure is uncommon during the midterm period, between 3 weeks and 6 months. The purpose of this study is to verify the incidence of failure of trabeculectomies with mitomycin-C (MMC) during the midterm period and to evaluate the safety and efficacy of laser suture lysis (LSL) for reversing it. PATIENTS AND METHODS: The authors reviewed the records of 130 consecutive patients who underwent trabeculectomy with adjunctive MMC. RESULTS: Fourteen patients (15 eyes) had increased intraocular pressure (IOP), between 21 and 185 days (median 41 days). LSL was effective in decreasing the IOP to acceptable levels in 10 (66.6%) of the 15 eyes. No complications related to LSL were noticed. CONCLUSION: The reversibility of midterm failure seems to be a unique feature of trabeculectomies with MMC.


Asunto(s)
Antibióticos Antineoplásicos/efectos adversos , Glaucoma/terapia , Mitomicina/efectos adversos , Hipertensión Ocular/cirugía , Trabeculectomía/efectos adversos , Adulto , Anciano , Antibióticos Antineoplásicos/administración & dosificación , Quimioterapia Adyuvante , Femenino , Estudios de Seguimiento , Humanos , Presión Intraocular , Terapia por Láser , Masculino , Persona de Mediana Edad , Mitomicina/administración & dosificación , Hipertensión Ocular/etiología , Soluciones Oftálmicas , Estudios Retrospectivos , Seguridad , Técnicas de Sutura , Insuficiencia del Tratamiento
13.
J Trauma ; 41(1): 114-9, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8676402

RESUMEN

OBJECTIVE: To acquire a better understanding of airbag-induced eye injuries, 25 cases are reviewed and an attempt is made to identify the causal mechanisms associated with each injury. DESIGN AND METHODS: The National Highway Traffic Safety Administration's National Accident Sampling System for the years 1984-1994 was accessed to identify automobile accidents that included airbag deployment and injury to the ocular region. The search provided 25 such cases with detailed studies of the accident scene and medical records of the injuries. The cases were comprehensively reviewed to determine the casual mechanisms associated with each group of injuries. RESULTS: The study determined that the injuries range from mild corneal abrasions to retinal detachment. Causation for each injury was determined and is detailed. The injuries were grouped according to location within the ocular region, and the distribution is shown. CONCLUSIONS: Most of the injuries were induced by impact with the fully deployed airbag, but the more severe ocular trauma resulted from the actively deploying airbag striking the occupant. Thus, ocular trauma from airbags can occur in very minor impacts. Additionally, the left eye seemed more vulnerable to injury than the right. Nontethered airbags have greater inflation distances that tend to increase the probability of injury. External parameters that may also increase the severity of eye injury include an unfastened seat belt, sitting too close to the steering wheel, or wearing glasses.


Asunto(s)
Accidentes de Tránsito , Airbags/efectos adversos , Lesiones Oculares/etiología , Adolescente , Adulto , Anciano , Niño , Preescolar , Lesiones de la Cornea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Desprendimiento de Retina/etiología , Perforaciones de la Retina/etiología , Estudios Retrospectivos
14.
J Glaucoma ; 5(2): 150, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8795749
15.
J Dev Behav Pediatr ; 16(3): 183-6, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7560121

RESUMEN

The association between nutritional status (percentage of weight for height) and infant-mother relationship was studied over 4 years in 38 children diagnosed with cystic fibrosis in the first year of life. Infant-mother relationship was assessed in a standardized laboratory observation. Although they could not be distinguished medically from the others at the time of diagnosis, infants showing a specific form of insecure relationship with their mothers (insecure-avoidant) differed from the others in: (1) failure to improve in nutritional status in the first year; (2) continuing decline in weight for height in the first 3 years; and (3) significantly lower weight for height at 1, 2, and 3 years of age. These data suggest that attention to mother-infant relationships, particularly feeding interactions, may improve nutritional status in children with cystic fibrosis.


Asunto(s)
Fibrosis Quística/psicología , Relaciones Madre-Hijo , Estado Nutricional , Apego a Objetos , Actividades Cotidianas/psicología , Estatura , Peso Corporal , Preescolar , Insuficiencia de Crecimiento/psicología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Estudios Longitudinales , Masculino , Determinación de la Personalidad , Estudios Prospectivos
16.
Ergonomics ; 38(5): 996-1010, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7737109

RESUMEN

In recent years, there has been an increased use of back supports in US industry to reduce the frequency and concomitant costs of lower-back disorders. The obvious question is, 'Can back supports relieve the load on the lumbar spine for employees engaged in industrial operations?'. This paper is directed towards answering this question because there have been mixed conclusions in the literature reporting on the efficacy of back supports. The literature concerning the biomechanical, physiological and psychophysical effects of back supports on the human spine has been reviewed as well as the use of back supports to control injury in the workplace. A critical assessment of the findings reported by various investigators has been made together with a discussion of the mechanisms used by the trunk muscles to provide extrinsic stability to the spine. It is hypothesized that the extrinsic stability of the spine is manifested through more than one mechanism. These mechanisms may act simultaneously or sequentially to stabilize the trunk. Finally, the ergonomics of back supports as a corporate policy are discussed.


Asunto(s)
Vértebras Lumbares/lesiones , Salud Laboral , Equipos de Seguridad , Traumatismos Vertebrales/prevención & control , Humanos , Vértebras Lumbares/fisiología , Soporte de Peso
19.
Ophthalmic Surg ; 25(2): 117-8, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8183509

RESUMEN

We report a surgical technique in which donor sclera is used to create a flap in glaucoma filtering procedures. This simple technique is helpful when the sclera is too thin to safely and effectively form an adequate scleral flap. The use of donor sclera allows the procedure to continue as a guarded procedure and prevents early postoperative hypotony.


Asunto(s)
Glaucoma de Ángulo Abierto/cirugía , Esclerótica , Colgajos Quirúrgicos/métodos , Donantes de Tejidos , Trabeculectomía/métodos , Anciano , Femenino , Humanos , Presión Intraocular , Hipotensión Ocular/prevención & control
20.
Ophthalmic Surg ; 24(5): 349-50, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8515955

RESUMEN

We report a surgical technique for repair of a disinserted scleral flap involving the use of two 10-0 nylon sutures, which are placed through the base of the scleral flap, and through and out of the peripheral cornea. These two sutures create a water-tight flap at the repaired hinged area. The procedure may thus continue as a trabeculectomy, permitting postoperative staged argon-laser suture lysis as well.


Asunto(s)
Esclerótica/cirugía , Colgajos Quirúrgicos , Trabeculectomía , Anciano , Femenino , Glaucoma de Ángulo Abierto/cirugía , Humanos , Nylons , Técnicas de Sutura , Suturas
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