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1.
Law Hum Behav ; 48(2): 148-161, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38602807

RESUMO

OBJECTIVE: Some scholars have criticized pretrial assessments for perpetuating racial bias in the criminal legal system by offering biased predictions of future legal system outcomes. Although these critiques have some empirical support, the scholarship has yet to examine the predictive validity and differential prediction of pretrial assessments across individuals by their age. Following the guidance of the life-course literature, the present study serves as the first age-graded evaluation of the Public Safety Assessment (PSA) focused on assessing whether the predictive validity and scoring predictions of the tool vary across the lifespan. HYPOTHESES: We expected that the predictive validity of the PSA scores would vary across the lifespan, such that the PSA underpredicts for younger individuals and overpredicts for older individuals. METHOD: The present study relied on pretrial information collected from 31,527 individuals during the Advancing Pretrial Policy and Research project. Logistic regression models were estimated to evaluate the differential prediction of the PSA for individuals ranging from 18 to 68 years of age. The results of bivariate models were used to produce area under the curve estimates at each year of age. RESULTS: The results of the present study provided some evidence that the PSA differentially predicted pretrial outcomes for individuals from 18 to 68 years of age. Specifically, the predictive validity of the New Criminal Arrest and the New Violent Criminal Arrest scales appears to improve as individuals become older, suggesting that these instruments are better able to predict pretrial outcomes for older individuals relative to younger individuals. CONCLUSION: The results suggest that the PSA is a valid predictor of pretrial outcomes and that the predictive validity of some PSA scores is impacted by age. These findings suggest that the age of the defendant should be accounted for when interpreting the new criminal arrest and new violent criminal arrest scores. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Assuntos
Criminosos , Humanos , Agressão , Aplicação da Lei , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso
2.
J Urban Health ; 100(6): 1128-1139, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37843742

RESUMO

Gun violence imparts a tremendous human and financial toll on local communities. Researchers have documented extensive mental and physical health consequences of generalized violence exposure but few studies have analyzed the particular impacts of gun violence on community well-being using nationally comprehensive data. We leverage a unique database of almost 16,000 neighborhoods in 100 US cities (2014-2019) to examine how year-over-year rates of gun violence correspond to overall neighborhood well-being and three aspects of community health: (1) health behaviors, (2) physical and mental health status, and (3) health prevention efforts. We simultaneously consider the reciprocal influence of neighborhood well-being on subsequent gun violence while accounting for concentrated disadvantage in communities. The results demonstrate that gun violence is associated with poorer community health in subsequent years, particularly health behaviors and mental/physical health status. Furthermore, we find substantial reciprocal effects for both gun violence and community health in their relationship to neighborhood concentrated disadvantage. These findings highlight the consequential role of gun violence in perpetuating cycles of harm in local communities.


Assuntos
Exposição à Violência , Violência com Arma de Fogo , Humanos , Cidades , Saúde Pública , Características de Residência
3.
J Adolesc ; 95(1): 56-69, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36199241

RESUMO

INTRODUCTION: Recent trends in reproductive rights have contributed to lasting concerns about adolescent childrearing in American society. Beyond being generally unprepared when raising a child, having a child during adolescence is associated with a variety of environmental, social, and psychological consequences for both the parents and the child. It is important to understand the factors contributing to adolescent childrearing. Although research has identified many factors that contribute to adolescent childrearing, a notable gap remains when considering the role of the correctional system and, in particular, the age-specific effects of confining adolescents in adult correctional facilities. METHODS: The current study examined the age-specific effects of time spent in adult correctional facilities from 13 to 34 years of age on childrearing between 14 and 35 years of age using the National Longitudinal Survey of Youth-1997 (NLSY97). The NLSY97 is a nationally representative sample of Males (51%) and Females (49%) born in the United States. Respondents of the NLSY97 were interviewed about life events beginning at age 7 and continued to participate in the study as recently as 2021. RESULTS: The results of the lagged growth curve models suggest that the time spent incarcerated between 13 and 17 years of age heightens the risk of childrearing between 14 and 18 years of age, an effect that is not observed during adulthood. CONCLUSION: Overall, the results suggest that the conditions adolescents are exposed to during incarceration in an adult correctional facility could contribute to a heightened likelihood of adolescent childrearing.


Assuntos
Prisioneiros , Masculino , Criança , Feminino , Humanos , Adolescente , Adulto , Estados Unidos/epidemiologia , Adulto Jovem , Educação Infantil , Fatores de Risco , Pais , Estabelecimentos Correcionais
4.
Twin Res Hum Genet ; 25(1): 24-39, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35506340

RESUMO

Discordant monozygotic (MZ) twin methodologies are considered one of the foremost statistical approaches for estimating the influence of environmental factors on phenotypic variance. Limitations associated with the discordant MZ twin approach generates an inability to estimate particular relationships and adjust estimates for the confounding influence of gene-nonshared environment interactions. Recent advancements in molecular genetics, however, can provide the opportunity to address these limitations. The current study reviews an alternative technique, genetically adjusted propensity scores (GAPS) matching, that integrates observed genetic and environmental information to adjust for the confounding of these factors in nonkin individuals. Simulations and a real data example were used to compare the GAPS matching approach to the discordant MZ twin method. Although the results of the simulated comparisons demonstrated that the discordant MZ twin approach remains the more robust statistical technique to adjust for shared environmental and genetic factors, GAPS matching - under certain conditions - could represent a viable alternative when MZ twin samples are unavailable. Overall, the findings suggest that GAPS matching can potentially provide an alternative to the discordant MZ twin approach when limited variation exists between identical twin pairs. Moreover, the ability to adjust for gene-nonshared environment interactions represents a potential advancement associated with the GAPS approach. The limitations of the approach, as well as polygenic risk scores, are also discussed.


Assuntos
Gêmeos Monozigóticos , Humanos , Pontuação de Propensão , Gêmeos Monozigóticos/genética
5.
Behav Genet ; 51(2): 137-143, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33400062

RESUMO

Heteropaternal superfecundation (HP) occurs when two or more ova are fertilized by sperm from separate males. The resulting siblings are genetically equivalent to half-siblings and share, on average, 25% of their inherited genetic material. In the absence of genetic testing HP siblings could be treated as dizygotic (DZ) twins in behavioral genetic analyses and bias heritability estimates in phenotypic decomposition models. However, the extent to which such misclassification could affect calculated estimates of heritability is currently unknown. Employing simulation analyses, the current study assessed the potential biasing impact across a variety of conditions varying by proportions of DZ twins, sample sizes, and low, moderate, and high levels of genetic and environmental contribution to phenotypic variance. Overall, the results indicated that misclassified HP siblings had minimal impact on estimates of heritability. Nonetheless, greater attention should be paid to the identification of HP siblings within existing and future twin datasets.


Assuntos
Gêmeos/classificação , Gêmeos/genética , Pai , Fertilidade/genética , Humanos , Padrões de Herança/genética , Irmãos , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética
6.
Violence Vict ; 36(1): 157-192, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33443229

RESUMO

Although many studies have highlighted the deleterious outcomes associated with access to firearms, others suggest gun ownership and carrying can have protective effects. This study attempts to adjudicate between these countervailing points and address several important gaps in the literature. To do so, data from the National Longitudinal Study of Adolescent to Adult Health were used to assess the long-term associations between gun ownership and gun carrying in late adolescence and violence and violent victimization in early adulthood. Results from propensity score matching analyses suggest gun carrying, but not gun ownership, is associated with a higher risk of experiencing a violent victimization (b = 0.080, 95% CI = .032, .127) and engaging in violence with a weapon (b = 0.885, 95% CI = .392, 1.378). Efforts to curb firearm-related violence should consider focusing on those who carry guns for additional counseling about these risks.


Assuntos
Vítimas de Crime , Armas de Fogo , Propriedade , Violência , Adolescente , Feminino , Humanos , Estudos Longitudinais , Masculino , Adulto Jovem
7.
Brain Inj ; 34(3): 375-384, 2020 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-32013624

RESUMO

Primary Objective: Prior research has demonstrated that traumatic brain injury (TBI) is associated with individual psychological symptoms. These findings, however, may not pertain to the influence of TBI during key developmental stages on the co-occurrence of negative psychological symptoms.Research Design: It was hypothesized that (H1) self-reported TBI is associated with adverse psychological effects, that (H2) self-reported TBI during adolescences is associated with both immediate and delayed adverse psychological effects, and finally, (H3) self-reported TBI during the early stages of adulthood is not associated with immediate psychological effects.Methods and Procedures: The current study employed a sample of adjudicated youth (N: 419 to 562) and structural equation modeling to estimate the association between self-reported TBI and subsequent adverse psychological effects.Results: Findings suggested that higher levels of self-reported TBI during adolescence were associated with higher levels of adverse psychological effects. These effects were both immediate and delayed. However, higher levels of self-reported TBI during adulthood were not associated with immediate adverse psychological effects.Conclusion: Overall, the findings suggest that deleterious outcomes related to self-reported TBI during key developmental stages include proximal and long-term adverse psychological effects.


Assuntos
Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/psicologia , Autorrelato , Adolescente , Feminino , Humanos , Masculino , Saúde Mental , Psicologia do Adolescente , Adulto Jovem
8.
Aggress Behav ; 46(3): 254-265, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32124999

RESUMO

Contemporary scholarship has demonstrated an association between traumatic brain injury (TBI) during adolescence and aggressive offending. Research, however, has yet to identify any mechanisms linking TBI to subsequent aggressive offending. Consequently, the current study hypothesized that adverse psychological effects is one such pathway. The current study used the Pathways to Desistance data set (n = 416) to examine the pathway of TBI to aggressive offending through adverse psychological effects. The findings of the structural equation model supported the hypothesized association. Specifically, increased exposure to TBI was indirectly associated with aggressive offending through adverse psychological effects. An additional supplemental analysis illustrated that a direct link between TBI and aggressive offending did not exist for the analytical sample. The findings suggested that the neurological disruptions commonly associated with TBI could result in direct increases in negative psychological outcomes and indirect increases in subsequent negative behavioral outcomes.


Assuntos
Agressão/psicologia , Lesões Encefálicas Traumáticas/epidemiologia , Transtornos Mentais/epidemiologia , Violência/psicologia , Adolescente , Lesões Encefálicas Traumáticas/psicologia , Feminino , Humanos , Masculino , Transtornos Mentais/psicologia , Índices de Gravidade do Trauma
9.
Connect Tissue Res ; 58(5): 424-437, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27662266

RESUMO

AIM OF THE STUDY: Large tendon defects involving extensive tissue loss present complex clinical problems. Surgical reconstruction of such injuries is normally performed by transplanting autogenous and allogenous soft tissues that are expected to remodel to mimic a normal tendon. However, the use of grafts has always been associated with significant limitations. Tissue engineering employing artificial scaffolds may provide acceptable alternatives. Gelatin is a hydrolyzed form of collagen that is bioactive, biodegradable, and biocompatible. The present study has investigated the suitability of gelatin scaffold for promoting healing of a large tendon-defect model in rabbits. MATERIALS AND METHODS: An experimental model of a large tendon defect was produced by partial excision of the Achilles tendon of the left hind leg in adult rabbits. To standardize and stabilize the length of the tendon defect a modified Kessler core suture was anchored in the sectioned tendon ends. The defects were either left untreated or filled with three-dimensional gelatin scaffold. Before euthanasia 60 days after injury, the progress of healing was evaluated clinically. Samples of healing tendon were harvested at autopsy and evaluated by gross, histopathologic, scanning, and transmission electron microscopy, and by biomechanical testing. RESULTS: The treated animals showed superior weight-bearing and physical activity compared with those untreated, while frequency of peritendinous adhesions around the healing site was reduced. The gelatin scaffold itself was totally degraded and replaced by neo-tendon that morphologically had significantly greater numbers, diameters, density, and maturation of collagen fibrils, fibers, and fiber bundles than untreated tendon scar tissue. It also had mechanically higher ultimate load, yield load, stiffness, maximum stress and elastic modulus, when compared to the untreated tendons. CONCLUSION: Gelatin scaffold may be a valuable option in surgical reconstruction of large tendon defects.


Assuntos
Tendão do Calcâneo , Gelatina , Traumatismos dos Tendões , Alicerces Teciduais/química , Tendão do Calcâneo/lesões , Tendão do Calcâneo/metabolismo , Tendão do Calcâneo/patologia , Animais , Bovinos , Gelatina/química , Gelatina/farmacologia , Masculino , Coelhos , Traumatismos dos Tendões/metabolismo , Traumatismos dos Tendões/patologia , Traumatismos dos Tendões/terapia
10.
J Adolesc Health ; 74(5): 989-995, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38402473

RESUMO

PURPOSE: To examine the relationship between youth incarceration in adult correctional facilities and mental health in early adulthood. METHODS: We analyzed nationally representative data from 1997 through 2019 (N = 8,961) using the National Longitudinal Survey of Youth 1997. An ordinary least squares regression model using inverse probability weights was used to assess the influence of youth incarceration in an adult facility on average mental health scores from age 18 to 37. RESULTS: Respondents incarcerated in an adult facility as a youth had poorer average mental health than those not held in adult prisons or jails over the course of the study period. Those incarcerated for longer in adult facilities also exhibited more mental health symptoms. DISCUSSION: Young people incarcerated in adult correctional facilities experience poorer long-term mental health related to depression and anxiety in early adulthood.


Assuntos
Transtornos Mentais , Prisioneiros , Adulto , Humanos , Adolescente , Adulto Jovem , Saúde Mental , Encarceramento , Prisões , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia
11.
Soc Sci Med ; 351: 116929, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38733888

RESUMO

RATIONALE: Community gun violence significantly shapes public health and collective well-being. Understanding how gun violence is associated with community health outcomes like mental health and sleep is crucial for developing interventions to mitigate disparities exacerbated by violence exposure. OBJECTIVE: This study examines the associations between community gun violence , insufficient sleep, and poor mental health across neighborhoods in the United States. METHODS: We utilized a novel database covering nearly 16,000 neighborhoods in 100 US cities from 2014 through 2019. Correlated trait fixed-effects models were employed to conduct all analyses while considering various neighborhood covariates such as concentrated disadvantage, demographic composition, population density, and proximity to trauma centers. RESULTS: Our analysis revealed that greater gun violence is associated with both insufficient sleep and poor mental health in subsequent years. There is a reciprocal relationship between poor mental health and insufficient sleep, with each partially mediating the other's association with community gun violence. Notably, gun violence exhibits the strongest direct association with poor sleep rather than with poor mental health. We found a consistent reciprocal relationship between sleep and mental health at the community level. CONCLUSIONS: The findings highlight a complex interplay between community violence, sleep, and mental health, underlining the importance of reducing community violence through numerous long-term interventions to address health disparities across the US.


Assuntos
Cidades , Violência com Arma de Fogo , Características de Residência , Humanos , Violência com Arma de Fogo/estatística & dados numéricos , Violência com Arma de Fogo/psicologia , Estados Unidos/epidemiologia , Características de Residência/estatística & dados numéricos , Saúde Mental/estatística & dados numéricos , Masculino , Feminino , Adulto , Sono
12.
J Psychoactive Drugs ; 55(2): 180-202, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35318899

RESUMO

The co-occurrence of illegal drug use, symptoms of depression, and a lower perception of general health among adolescents continues to be of substantive interest for researchers and the general public alike. Research on this topic, however, remains relatively stagnant, focusing on narrow developmental periods and each association independently, with limited consideration for the existence of a nexus between the three constructs as individuals age. Considering these limitations, the current study examines the longitudinal progression, from adolescence to early adulthood, of illegal drug use, symptoms of depression, and a lower perception of general health. The National Longitudinal Survey of Youth 1997 (NLSY97; N = 8,984), measures over an eleven-year data collection period, and between-and within-individual analytical strategies were used to evaluate the nexus between the constructs. The findings suggested that illegal drug use, depressive symptoms, and general health at previous time periods directly and indirectly predicted illegal drug use, depressive symptoms, and general health at subsequent time periods. Moreover, the within-individual change in illegal drug use was associated with the change in depressive symptoms, and the change in depressive symptoms was associated with the change in general health. Practitioners should consider this co-occurrence when treating symptoms related to illegal drug use, symptoms of depression, and physical health.


Assuntos
Drogas Ilícitas , Transtornos Relacionados ao Uso de Substâncias , Adolescente , Humanos , Adulto , Depressão/epidemiologia , Estudos Longitudinais , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Nível de Saúde , Drogas Ilícitas/efeitos adversos
13.
JAMA Netw Open ; 6(7): e2321805, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-37405770

RESUMO

Importance: Youths incarcerated in adult correctional facilities are exposed to a variety of adverse circumstances that could diminish psychological and physical health, potentially leading to early mortality. Objective: To evaluate whether being incarcerated in an adult correctional facility as a youth was associated with mortality between 18 and 39 years of age. Design, Setting, and Participants: This cohort study relied on longitudinal data collected from 1997 to 2019 as part of the National Longitudinal Survey of Youth-1997, a nationally representative sample of 8984 individuals born in the United States between January 1, 1980, and December 1, 1984. The data analyzed for the current study were derived from annual interviews between 1997 and 2011 and interviews every other year from 2013 to 2019 (19 interviews in total). Participants were limited to respondents aged 17 years or younger during the 1997 interview and alive during their 18th birthday (8951 individuals; >99% of the original sample). Statistical analysis was performed from November 2022 to May 2023. Intervention: Incarceration in an adult correctional facility before the age of 18 years compared with being arrested before the age of 18 years or never arrested or incarcerated before the age of 18 years. Main Outcomes and Measures: The main outcome for the study was age at mortality between 18 and 39 years of age. Results: The sample of 8951 individuals included 4582 male participants (51%), 61 American Indian or Alaska Native participants (1%), 157 Asian participants (2%), 2438 Black participants (27%), 1895 Hispanic participants (21%), 1065 participants of other race (12%), and 5233 White participants (59%). A total of 225 participants (3%) died during the study period, with a mean (SD) age at death of 27.7 (5.9) years. Incarceration in an adult correctional facility before the age of 18 years was associated with an increased risk of earlier mortality between 18 and 39 years of age compared with individuals who were never arrested or incarcerated before the age of 18 years (time ratio, 0.67; 95% CI, 0.47-0.95). Being arrested before the age of 18 years was associated with an increased risk of earlier mortality between 18 and 39 years of age when compared with individuals who were never arrested or incarcerated before the age of 18 years (time ratio, 0.82; 95% CI, 0.73-0.93). Conclusions and Relevance: In this cohort study of 8951 youths, the survival model suggested that being incarcerated in an adult correctional facility may be associated with an increased risk of early mortality between 18 and 39 years of age.


Assuntos
Mortalidade Prematura , Prisioneiros , Adolescente , Adulto , Humanos , Masculino , Adulto Jovem , Estudos de Coortes , Estabelecimentos Correcionais , Hispânico ou Latino , Estados Unidos/epidemiologia , Feminino
14.
Int J Offender Ther Comp Criminol ; 66(2-3): 209-226, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33522337

RESUMO

Inmate misconduct continues to threaten safety and order within correctional institutions. Yet few studies have examined its longitudinal nature. In this paper we explore the correspondence between correctional programming and inmate misconduct. To do this, we draw from Linning et al.'s time-course framework devised to improve the design and evaluation of interventions by considering effects that can occur before, during, and after programming. We provide the first empirical demonstration of their framework using prisoner misconduct data collected from all Ohio prisons between January 2008 and June 2012. A cross-lagged panel analysis provides support for the use of a time-course framework. Results show that misconduct decreased during programming. However, we observed increases in misconduct prior to and following exposure to programming. Our results suggest that future work needs to improve our understanding of causal mechanisms of inmate misconduct and when their effects are expected.


Assuntos
Prisioneiros , Comportamento Problema , Humanos , Ohio , Prisões
15.
Arch Orthop Trauma Surg ; 130(12): 1451-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20130893

RESUMO

INTRODUCTION: This study evaluated the effects of metrenperone on healing of unilateral, collagenase-induced lesions in the Superficial Digital Flexor Tendons (SDFT) of rabbits. METHODS: After controlled injury of the left SDFT, nine rabbits received daily treatment with metrenperone for 28 days. Another nine were untreated controls; in both groups the contra-lateral tendons served as uninjured controls. Histological and ultrastructural changes, mechanical properties, dry weight, collagen content, and amount of DNA in healing and control tendons were assessed 28 days after injury. RESULTS: Restoration of structural hierarchy was more organized in treated than in untreated tendons while cellularity was greater in the latter. At the ultrastructural level, collagen in treated lesions was predominantly in the form of small-diameter, new fibrils, with few large, old fibrils; in untreated lesions there was a high proportion of large, old fibrils but relatively few small, new ones. The amount of DNA in untreated injuries was much greater than in normal tendons, while in treated lesions it was not significantly different from that of uninjured controls. There were no significant differences in total collagen, stiffness and ultimate strength of injured, treated, and untreated tendons 28 days after injury. Both were significantly weaker than their corresponding contralaterals. CONCLUSIONS: The findings suggest that metrenperone had positive effects on collagen turnover, remodelling, and organization during acute inflammation and fibroplasia. Provided that the new fibrils subsequently matured in a normal manner, mechanical characteristics of the organized scar should be better than those of an untreated lesion.


Assuntos
Colágeno/metabolismo , Piperidinas/farmacologia , Antagonistas do Receptor 5-HT2 de Serotonina/farmacologia , Traumatismos dos Tendões/metabolismo , Tendões/metabolismo , Cicatrização/efeitos dos fármacos , Animais , Fenômenos Biomecânicos , Colagenases , DNA/análise , Feminino , Coelhos , Traumatismos dos Tendões/induzido quimicamente , Traumatismos dos Tendões/tratamento farmacológico , Traumatismos dos Tendões/patologia , Tendões/efeitos dos fármacos , Tendões/patologia , Tendões/ultraestrutura , Resistência à Tração/efeitos dos fármacos
16.
Connect Tissue Res ; 49(5): 351-60, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18991088

RESUMO

This study explored the hypothesis that local administration of a polysulphated glycosaminoglycan (PSGAG) in the early phase of healing of a standard collagenase-induced tendon injury in the superficial digital flexor tendon of the rabbit would reduce the degenerative effects of inflammatory mediators and proteases and preserve normal tendon morphology, composition, and biomechanical properties. Histological and ultrastructural changes together with the mechanical properties, dry weight, collagen content, and amount of DNA in healing tissue at the site of the lesion were assessed in treated and untreated animals. In treated lesions 28 days after injury, the normal orientation of tenoblasts and collagen fibrils was well preserved compared with the disorganized scar formation seen in untreated animals. The degree of cellularity was significantly higher in the untreated lesions. At the ultrastructural level the collagen in the healing tissue of the treated animals consisted of a mixture of small diameter, new regenerated fibrils intermingled with well-preserved large diameter, old fibrils, aligned to the long axis of the tendon; in untreated animals small, randomly arranged new fibrils predominated. The diameters of treated tendons had returned to normal, but in untreated animals the injured tendons remained significantly thicker than their controls. The percentage dry weight and collagen contents of treated injured tendons approximated those of control normal tendons, whereas those of untreated tendons were significantly less than those of the control values. The DNA content of injured treated tendons was not significantly different from that of normal contralateral controls, while in the untreated tendons it was significantly higher. There were no significant differences between the normal and the contralateral treated injured tendons in ultimate strength, fatigue strength, stiffness, and maximum absorbed energy. However in the untreated animals, although the tendon diameter was significantly greater, the ultimate strength, fatigue strength, stiffness, and maximum absorbed energy were significantly lower than the contralateral control. These data suggest that polysulphated glycosaminoglycans are effective in restoring the morphological, biochemical, and biomechanical properties of injured soft connective tissues and may be of clinical value in the treatment of acute tendon injury.


Assuntos
Glicosaminoglicanos/uso terapêutico , Traumatismos dos Tendões/tratamento farmacológico , Tendões/efeitos dos fármacos , Animais , Colagenases/farmacologia , Feminino , Microscopia Eletrônica de Transmissão , Coelhos , Estresse Mecânico , Traumatismos dos Tendões/induzido quimicamente , Tendões/patologia , Tendões/ultraestrutura , Resistência à Tração/efeitos dos fármacos , Resistência à Tração/fisiologia
17.
Prog Neurobiol ; 73(6): 397-445, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15313334

RESUMO

Production of energy for the maintenance of ionic disequilibria necessary for generation and transmission of nerve impulses is one of the primary functions of the brain. This review attempts to link the plethora of information on the maturation of the central nervous system with the ontogeny of ATP metabolism, placing special emphasis on variations that occur during development in different brain regions and across the mammalian species. It correlates morphological events and markers with biochemical changes in activities of enzymes and pathways that participate in the production of ATP. The paper also evaluates alterations in energy levels as a function of age and, based on the tenet that ATP synthesis and utilization cannot be considered in isolation, investigates maturational profiles of the key processes that utilize energy. Finally, an attempt is made to assess the relevance of currently available animal models to improvement of our understanding of the etiopathology of various disease states in the human infant. This is deemed essential for the development and testing of novel strategies for prevention and treatment of several severe neurological deficits.


Assuntos
Química Encefálica/fisiologia , Metabolismo Energético/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Vasos Sanguíneos/fisiologia , Água Corporal/fisiologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/ultraestrutura , Colesterol/metabolismo , DNA/metabolismo , Espaço Extracelular/fisiologia , Humanos , Canais Iônicos/fisiologia , Cinética , Mitocôndrias/metabolismo , Mitocôndrias/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Neurônios/fisiologia
18.
J Tissue Eng Regen Med ; 10(6): 451-65, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-23637093

RESUMO

This study was designed to investigate the effectiveness of hybridized, three-dimensional (3D) collagen implants in repair of experimentally-induced tendon defects in rabbits. Seventy-five mature New Zealand albino rabbits were divided into treated (n = 50) and control (n = 20) groups. The left Achilles tendon was completely transected and 2 cm excised. In treated animals defects were filled with hybridized collagen implants and repaired with sutures. In control rabbits tendon defects were sutured similarly but the gap was left untreated. Changes in injured and normal contralateral tendons were assessed weekly by ultrasonography. Among the treated animals, small pilot groups were euthanized at 5, 10, 15, 20, 30, 40 (n = 5 at each time interval) and the remainder (n = 20) at 60 days post-injury. All control animals were euthanized at 60 days. Tendon lesions of all animals were examined morphologically and histologically immediately after death. Those of the experimental groups (n = 20 for each) were examined for gross pathological, histopathological and ultrastructural changes together with dry matter content at 60 days post-injury, as were the normal, contralateral tendons of both groups. In comparison with healing lesions of control animals, the treated tendons showed greater numbers of mature tenoblasts and tenocytes, minimal peritendinous adhesions and oedema, together with greater echogenicity, homogeneity and fibril alignment. Fewer chronic inflammatory cells were present in treated than control tendons. Hybridized collagen implants acted as scaffolds for tenoblasts and longitudinally-orientated newly-formed collagen fibrils, which encouraged tendon repair with homogeneous, well-organized highly aligned scar tissue that was histologically and ultrastructurally more mature than in untreated controls. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Implantes Absorvíveis , Bioprótese , Nanoestruturas/química , Traumatismos dos Tendões , Tendões/metabolismo , Alicerces Teciduais/química , Animais , Coelhos , Traumatismos dos Tendões/metabolismo , Traumatismos dos Tendões/patologia , Traumatismos dos Tendões/cirurgia , Tendões/patologia
19.
J Neuropathol Exp Neurol ; 62(3): 292-303, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12638733

RESUMO

Intraventricular hemorrhage is a common complication of prematurity. Posthemorrhagic ventricular dilation (PHVD) has a high rate of disability and no safe and effective treatment. Its pathogenesis is poorly understood, largely because of the lack of a satisfactory animal model. We have developed a model of neonatal PHVD in the rat. Seven-day-old (P7) Wistar rat pups were given 80-microl injections of citrated rat blood or artificial cerebrospinal fluid (CSF) into alternate lateral ventricles on P7 and P8. Intracranial pressure was monitored and increased briefly by over 8-fold. Some rats received further 10-microl intraventricular injections of India ink on P21. Animals were weighed daily and simple neurologic tests performed. On P21 (or P22 if India ink had been injected), the rats were perfusion-fixed and blocks processed for paraffin histology. Sixty-five percent of pups injected with blood and 50% injected with artificial CSF developed dilated lateral ventricles, with patchy loss of ependyma, marked astrocytic gliosis, and rarefaction of periventricular white matter. India ink injection revealed slow transit of CSF from the dilated lateral ventricles but eventual passage into the subarachnoid space. Pups that had received intraventricular injections but did not develop ventricular dilation nonetheless had lighter brains than littermate controls (p < 0.001). Body weights were not significantly different from controls. Hydrocephalic animals had reduced motor performance as assessed by a grip traction test (p = 0.0002). This model is well suited to studying the pathogenesis of PHVD.


Assuntos
Carbono , Hemorragia Cerebral/patologia , Ventrículos Cerebrais/patologia , Modelos Animais de Doenças , Animais , Animais Recém-Nascidos , Encéfalo/patologia , Ventrículos Cerebrais/química , Corantes , Feminino , Tamanho do Órgão , Gravidez , Ratos , Ratos Wistar
20.
J Cereb Blood Flow Metab ; 23(5): 513-30, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12771566

RESUMO

This review analyzes, in some depth, results of studies on the effect of lowered temperatures on cerebral energy metabolism in animals under normal conditions and in some selected pathologic situations. In sedated and paralyzed mammals, acute uncomplicated 0.5- to 3-h hypothermia decreases the global cerebral metabolic rate for glucose (CMR(glc)) and oxygen (CMRo(2)) but maintains a slightly better energy level, which indicates that ATP breakdown is reduced more than its synthesis. Intracellular alkalinization stimulates glycolysis and independently enhances energy generation. Lowering of temperature during hypoxia-ischemia slows the rate of glucose, phosphocreatine, and ATP breakdown and lactate and inorganic phosphate formation, and improves recovery of energetic parameters during reperfusion. Mild hypothermia of 12 to 24-h duration after normothermic hypoxic-ischemic insults seems to prevent or ameliorate secondary failures in energy parameters. The authors conclude that lowered head temperatures help to protect and maintain normal CNS function by preserving brain ATP supply and level. Hypothermia may thus prove a promising avenue in the treatment of stroke and trauma and, in particular, of perinatal brain injury.


Assuntos
Metabolismo Energético/fisiologia , Hipotermia Induzida , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/terapia , Animais , Encéfalo/metabolismo , Humanos , Mamíferos
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