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1.
Pediatr Radiol ; 51(6): 1044-1050, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33755750

RESUMO

Abusive intra-abdominal injuries are less common than other types of injuries, such as fractures and bruises, identified in victims of child physical abuse, but they can be deadly. No single abdominal injury is pathognomonic for abuse, but some types and constellations of intra-abdominal injuries are seen more frequently in abused children. Identification of intra-abdominal injuries can be important clinically or forensically. Injuries that do not significantly change clinical management can still elevate a clinician's level of concern for abuse and thereby influence subsequent decisions affecting child protection efforts. Abusive intra-abdominal injuries can be clinically occult, necessitating screening laboratory evaluations to inform decisions regarding imaging. Once detected, consideration of developmental abilities of the child, type and constellation of injuries, and the forces involved in any provided mechanism of trauma are necessary to inform assessments of plausibility of injury mechanisms and level of concern for abuse. Here we describe the clinical, laboratory and imaging evaluation of the abdomen in the setting of suspected child abuse.


Assuntos
Traumatismos Abdominais , Maus-Tratos Infantis , Fraturas Ósseas , Abdome , Traumatismos Abdominais/diagnóstico por imagem , Criança , Maus-Tratos Infantis/diagnóstico , Humanos , Lactente , Programas de Rastreamento
2.
J Clin Med ; 8(5)2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31137728

RESUMO

Breast density, a measure of dense fibroglandular tissue relative to non-dense fatty tissue, is confirmed as an independent risk factor of breast cancer. Although there has been an increasing interest in the quantitative assessment of breast density, no research has investigated the optimal technical approach of breast MRI in this aspect. Therefore, we performed a systematic review and meta-analysis to analyze the current studies on quantitative assessment of breast density using MRI and to determine the most appropriate technical/operational protocol. Databases (PubMed, EMBASE, ScienceDirect, and Web of Science) were searched systematically for eligible studies. Single arm meta-analysis was conducted to determine quantitative values of MRI in breast density assessments. Combined means with their 95% confidence interval (CI) were calculated using a fixed-effect model. In addition, subgroup meta-analyses were performed with stratification by breast density segmentation/measurement method. Furthermore, alternative groupings based on statistical similarities were identified via a cluster analysis employing study means and standard deviations in a Nearest Neighbor/Single Linkage. A total of 38 studies matched the inclusion criteria for this systematic review. Twenty-one of these studies were judged to be eligible for meta-analysis. The results indicated, generally, high levels of heterogeneity between study means within groups and high levels of heterogeneity between study variances within groups. The studies in two main clusters identified by the cluster analysis were also subjected to meta-analyses. The review confirmed high levels of heterogeneity within the breast density studies, considered to be due mainly to the applications of MR breast-imaging protocols and the use of breast density segmentation/measurement methods. Further research should be performed to determine the most appropriate protocol and method for quantifying breast density using MRI.

3.
J Urol ; 184(1): 378-85, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20488483

RESUMO

PURPOSE: The prevalence of bladder dysfunctions increases with age. In humans it is difficult to separate changes related to exogenous factors from those directly related to the aging process. Some confounding variables can be avoided by studying age related changes in an animal model. We evaluated the impact of age on bladder function in vivo and in vitro, and characterized the corresponding morphological changes. MATERIALS AND METHODS: Young (4 to 6 months old) and old (older than 28 to 30 months) male Fischer/Brown Norway rats were used in the study. Cystometric studies were done in conscious, freely moving rats. After cystometry tissue strips from the bladder body were used in in vitro studies of muscarinic receptor activation and electrical field stimulation, and histological examination. RESULTS: Old rats had higher bladder weight than young rats but the bladder-to-body weight ratio did not change. We noted significant age related differences in 8 of 10 cystometric parameters. Old rats had increased bladder capacity, post-void residual volume, micturition volume and frequency, baseline and intermicturition pressure, and spontaneous activity but decreased micturition pressure. Bladder strip responses to carbachol and electrical field stimulation were significantly lower in old than in young rats. Histological examination revealed urothelial thinning, lower muscle mass and higher collagen content in the bladders of old vs young rats. CONCLUSIONS: Physiological aging alters bladder function in male rats even when external factors remain constant. Thus, in old rats bladder capacity, post-void residual urine and spontaneous activity are higher, and responses to muscarinic receptor stimulation and electrical field stimulation are lower than in young rats. Such changes correspond to findings in aging human bladders, supporting the view that the Fischer/Brown Norway rat is a useful model in which to study age related bladder function changes.


Assuntos
Envelhecimento/fisiologia , Bexiga Urinária/fisiopatologia , Animais , Carbacol/farmacologia , Estimulação Elétrica , Modelos Logísticos , Masculino , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiopatologia , Ratos , Ratos Endogâmicos F344 , Fatores de Risco , Processamento de Sinais Assistido por Computador , Estatísticas não Paramétricas , Transdutores de Pressão , Bexiga Urinária/efeitos dos fármacos , Cateterismo Urinário
4.
Radiat Res ; 166(6): 892-9, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17149974

RESUMO

Whole-brain irradiation is used for the treatment of brain tumors, but can it also induce neural changes, with progressive dementia occurring in 20-50% of long-term survivors. The present study investigated whether 45 Gy of whole-brain irradiation delivered to 12-month-old Fischer 344 x Brown Norway rats as nine fractions over 4.5 weeks leads to impaired Morris water maze (MWM) performance 12 months later. Compared to sham-irradiated rats, the irradiated rats demonstrated impaired MWM performance. The relative levels of the NR1 and NR2A but not the NR2B subunits of the NMDA receptor were significantly higher in hippocampal CA1 of irradiated rats compared to control rats. No significant differences were detected for these NMDA subunits in CA3 or dentate gyrus. Further analysis of CA1 revealed that the relative levels of the GluR1 and GluR2 subunits of the AMPA receptor and synaptophysin were not altered by whole-brain irradiation. In summary, a clinically relevant regimen of fractionated whole-brain irradiation led to significant impairments in spatial learning and reference memory and alterations in the relative levels of subunits of the NMDA, but not the AMPA, receptors in hippocampal CA1. These findings suggest for the first time that radiation-induced cognitive impairments may be associated with alterations in glutamate receptor composition.


Assuntos
Lesões Encefálicas/metabolismo , Hipocampo/fisiologia , Hipocampo/efeitos da radiação , Transtornos da Memória/etiologia , Transtornos da Memória/metabolismo , Lesões por Radiação/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Lesões Encefálicas/etiologia , Masculino , Especificidade de Órgãos , Subunidades Proteicas/metabolismo , Doses de Radiação , Lesões por Radiação/etiologia , Ratos , Ratos Endogâmicos F344
5.
Am J Physiol Endocrinol Metab ; 291(3): E604-10, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16912061

RESUMO

Decreases in plasma IGF-I levels that occur with age have been hypothesized to contribute to the genesis of brain aging. However, support for this hypothesis would be strengthened by evidence that growth hormone (GH)/IGF-I deficiency in young animals produces a phenotype similar to that found in aged animals. As a result, we developed a unique model of adult-onset GH/IGF-I deficiency by using dwarf rats specifically deficient in GH and IGF-I. The deficiency in plasma IGF-I is similar to that observed with age (e.g., 50% decrease), and replacement of GH restores levels of IGF-I to that found in young animals with normal GH levels. The present study employs this model to investigate the effects of circulating GH and IGF-I on local cerebral glucose utilization (LCGU). Analysis of LCGU indicated that GH/IGF-I-deficient animals exhibit a 29% decrease in glucose metabolism in many brain regions, especially those involved in hippocampally dependent processes of learning and memory. Similarly, a high correlation between plasma IGF-I levels and glucose metabolism was found in these areas. The deficiency in LCGU was not associated with alterations in GLUT1, GLUT3, or hexokinase activity. A 15% decrease in ATP levels was also found in hippocampus of GH-deficient animals, providing compelling data that circulating GH and IGF-I have significant effects on the regulation of glucose utilization and energy metabolism in the brain. Furthermore, our results provide important data to support the conclusion that deficiencies in circulating GH/IGF-I contribute to the genesis of brain aging.


Assuntos
Trifosfato de Adenosina/metabolismo , Encéfalo/metabolismo , Glucose/metabolismo , Hormônio do Crescimento/deficiência , Fator de Crescimento Insulin-Like I/deficiência , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Córtex Cerebral/metabolismo , Modelos Animais de Doenças , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 3/metabolismo , Hormônio do Crescimento/genética , Hormônio do Crescimento/farmacologia , Hipocampo/metabolismo , Hipotálamo/metabolismo , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Ratos , Ratos Endogâmicos Lew , Ratos Mutantes
6.
Endocrinology ; 146(7): 2920-32, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15790724

RESUMO

Disruption of the insulin/IGF-I pathway increases life span in invertebrates. However, effects of decreased IGF-I signaling in mammalian models remain controversial. Using a rodent model with a specific and limited deficiency of GH and IGF-I, we report that GH and IGF-I deficiency throughout life [GH deficiency (GHD)] has no effect on life span compared with normal, heterozygous animals. However, treatment of GHD animals with GH from 4-14 wk of age [adult-onset (AO) GHD] increased median and maximal life span by 14% and 12%, respectively. Analysis of end-of-life pathology indicated that deficiency of these hormones decreased tumor incidence in GHD and AO-GHD animals (18 and 30%, respectively) compared with heterozygous animals and decreased the severity of, and eliminated deaths from, chronic nephropathy. Total disease burden was reduced by 24% in GHD and 16% in AO-GHD animals. Interestingly, the incidence of intracranial hemorrhage increased by 154 and 198% in GHD and AO-GHD animals, respectively, compared with heterozygous animals. Deaths from intracranial hemorrhage in AO-GHD animals were delayed by 14 wk accounting for the increased life span compared with GHD animals. The presence of GH and IGF-I was necessary to maximize reproductive fitness and growth of offspring early in life and to maintain cognitive function and prevent cartilage degeneration later in life. The diverse effects of GH and IGF-I are consistent with a model of antagonistic pleiotropy and suggest that, in response to a deficiency of these hormones, increased life span is derived at the risk of functional impairments and tissue degeneration.


Assuntos
Envelhecimento , Hormônio do Crescimento/deficiência , Fator de Crescimento Insulin-Like I/deficiência , Longevidade , Neoplasias/prevenção & controle , Erros Inatos do Metabolismo de Esteroides/patologia , Erros Inatos do Metabolismo de Esteroides/fisiopatologia , Animais , Composição Corporal , Temperatura Corporal , Ritmo Circadiano , Nanismo/genética , Hormônio do Crescimento/farmacologia , Força da Mão , Heterozigoto , Homozigoto , Longevidade/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto , Atividade Motora , Ratos , Ratos Endogâmicos Lew , Reprodução
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