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1.
Soc Work Public Health ; : 1-12, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769819

RESUMO

This study delves into the mental health experiences of Black male veterans, bridging their military service with the historical context of Black men's mental health. Amid limited literature on this demographic, qualitative methods, including focus groups, are utilized to gather nuanced insights. Themes such as mental health awareness gaps, diverse therapy encounters, familial and social stigmatization, and lacking support networks emerge. The study underscores the urgent need for heightened attention to this overlooked population within social work research, education, and practice. It advocates for an inclusive, culturally sensitive approach in social work, offering implications for practitioners, educators, and curriculum development tailored to the unique needs of Black male veterans. Despite constraints, this research provides vital perspectives, urging further inquiry and support initiatives to better comprehend and aid the mental well-being of Black male veterans.

2.
J Phys Condens Matter ; 34(19)2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35193132

RESUMO

We report on a microscopic study of the noncentrosymmetric superconductor W3Al2C (withTc= 7.6 K), mostly by means of27Al- and13C nuclear magnetic resonance (NMR). Since in this material the density of states at the Fermi level is dominated by the tungsten's 5dorbitals, we expect a sizeable spin-orbit coupling (SOC) effect. The normal-state electronic properties of W3Al2C resemble those of a standard metal, but with a Korringa product 1/(T1T) significantly smaller than that of metallic Al, reflecting the marginal role played bys-electrons. In the superconducting state, we observe a reduction of the Knight shift and an exponential decrease of the NMR relaxation rate 1/T1, typical ofs-wave superconductivity (SC). This is further supported by the observation of a small but distinct coherence peak just belowTcin the13C NMR relaxation-rate, in agreement with the fully-gapped superconducting state inferred from the electronic specific-heat data well belowTc. The above features are compared to those of members of the same family, in particular, Mo3Al2C, often claimed to exhibit unconventional SC. We discuss why, despite the enhanced SOC, W3Al2C does not show spin-triplet features in its superconducting state and consider the broader consequences of our results for noncentrosymmetric superconductors in general.

3.
Clin Soc Work J ; 49(4): 505-514, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34728866

RESUMO

Undoubtedly, the 2019 novel coronavirus, also known as COVID-19, has put mental health clinicians under stress. Despite the promise of self-care in assuaging stress, very few, if any, studies have investigated the impact of self-care on stress among mental health professionals. This exploratory study examined COVID-19 related distress, self-care, and the predictive relationship between the two. Primary data were collected from a sample of mental health social work clinicians in one southeastern state (N = 1568). Results indicate that participants were experiencing mild peritraumatic distress associated with COVID-19. Participants who were married, identified as heterosexual or straight, financially stable, and in good physical/mental health were experiencing less distress than other mental health clinicians in the sample. Analyses revealed that higher self-care practices predict significantly less distress. Overall, data suggest that self-care can be integral to assuaging distress among mental health clinicians. This study offers insight into how to support mental health practitioners during COVID-19.

4.
Hum Vaccin Immunother ; 16(2): 436-444, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31361179

RESUMO

Including dental health providers in human papillomavirus (HPV) vaccination could reduce rising rates in HPV-associated oropharyngeal cancer (HPV-OPC). This study assessed Utah dentists' perspectives on providing HPV vaccination education and services in the dental setting. A cross-sectional, 70-item self-administered survey was conducted among a convenience sample of N = 203 practicing Utah dentists. Statistical analyses included Chi Square tests of independence, scaled scores and Cronbach's alpha coefficients. Majority of Utah dentists surveyed perceived that discussing the link between HPV and OPC and recommending the HPV vaccine is within their scope of practice, but not administration of the HPV vaccine. Dentists with >10 minutes of patient education per week were less likely to be concerned about the cultural, social norms or religious ideology of discussing HPV with their patients (p = .024). Rural dentists were more concerned about the safety and liability of the HPV vaccine (p = .011). Good internal consistency was observed survey items regarding barriers and willing to engage in HPV vaccination practices. Dental providers were interested in HPV training and patient education brochures as strategies, but less interested in administering the HPV vaccine. Dental associations support dentists' engagement in HPV education and HPV-OPC prevention. This is the first study in Utah to examine dentists' perspectives on HPV vaccination. Findings have implications for program planning, intervention development, and future research.


Assuntos
Alphapapillomavirus , Infecções por Papillomavirus , Vacinas contra Papillomavirus , Estudos Transversais , Odontólogos , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Infecções por Papillomavirus/prevenção & controle , Inquéritos e Questionários , Utah , Vacinação
5.
Bone Joint J ; 101-B(2): 213-220, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30700121

RESUMO

AIMS: The aim of this study was to assess the influence of obesity on the clinical outcomes and survivorship ten years postoperatively in patients who underwent a fixed-bearing unicompartmental knee arthroplasty (UKA). PATIENTS AND METHODS: We prospectively followed 184 patients who underwent UKA between 2003 and 2007 for a minimum of ten years. A total of 142 patients with preoperative body mass index (BMI) of < 30 kg/m2 were in the control group (32 male, 110 female) and 42 patients with BMI of ≥ 30 kg/m2 were in the obese group (five male, 37 female). Pre- and postoperative range of movement (ROM), Knee Society Score (KSS), Oxford Knee Score (OKS), 36-Item Short-Form Health Survey (SF-36), and survivorship were analyzed. RESULTS: Patients in the obese group underwent UKA at a significantly younger mean age (56.5 years (sd 6.4)) than those in the control group (62.4 years (sd 7.8); p < 0.001). There was no significant difference in preoperative functional scores. However, those in the obese group had a significantly lower ROM (116° (sd 15°) vs 123° (sd 17°); p = 0.003). Both groups achieved significant improvement in outcome scores regardless of BMI, ten years postoperatively. All patients achieved the minimal clinically important difference (MCID) for OKS and KSS. Both groups also had high rates of satisfaction (96.3% in the control group and 97.5% in the obese group) and the fulfilment of expectations (94.9% in the control group and 95.0% in the obese group). Multiple linear regression showed a clear association between obesity and a lower OKS two years postoperatively and Knee Society Function Score (KSFS) ten years postoperatively. After applying propensity matching, obese patients had a significantly lower KSFS, OKS, and physical component score (PCS) ten years postoperatively. Seven patients underwent revision to total knee arthroplasty (TKA), two in the control group and five in the obese group, resulting in a mean rate of survival at ten years of 98.6% and 88.1%, respectively (p = 0.012). CONCLUSION: Both groups had significant improvements in functional and quality-of-life scores postoperatively. However, obesity was a significant predictor of poorer improvement in clinical outcome and an increased rate of revision ten years postoperatively.


Assuntos
Artroplastia do Joelho , Prótese do Joelho , Obesidade/complicações , Osteoartrite do Joelho/cirurgia , Fatores Etários , Idoso , Artroplastia do Joelho/instrumentação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/complicações , Satisfação do Paciente , Estudos Prospectivos , Desenho de Prótese , Falha de Prótese , Qualidade de Vida , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Reoperação , Resultado do Tratamento
6.
Arch Osteoporos ; 13(1): 130, 2018 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-30456726

RESUMO

Potential FRAX®-based major osteoporotic fracture (MOF) and hip fracture (HF) intervention thresholds (ITs) for postmenopausal Singaporean women were explored. Age-dependent ethnic-specific and weighted mean ITs progressively increased with increasing age. Fixed ITs were derived via discriminatory value analysis. MOF and HF ITs with highest the Youden index were chosen as optimal. INTRODUCTION: We aimed to explore FRAX®-based intervention thresholds (ITs) to potentially guide osteoporosis treatment in Singapore, a multi-ethnic nation. METHOD: One thousand and one Singaporean postmenopausal community-dwelling women belonging to Chinese, Malay and Indian ethnicities underwent clinical risk factor (CRF) and BMD assessment. FRAX® major osteoporotic fracture (MOF) and hip fracture (HF) probabilities were calculated using ethnic-specific models. We employed the translational logic adopted by NOGG (UK), whereby osteoporosis treatment is recommended to any postmenopausal woman whose fracture probability based on other CRFs is similar to or exceeds that of an age-matched woman with a fracture. Using the same logic, ethnic-specific and mean weighted age-dependent ITs were computed. Employing these age-dependent ITs as a reference, the performance of fixed (age-independent) ITs were examined using ROC curves and discriminatory analysis, with the highest Youden index (YI) (sensitivity + specificity - 1) used to identify the optimal MOF and HF ITs. RESULTS: The mean age was 58.9 (6.9) years. Seven hundred and eighty-nine (79%) women were Chinese, 136 (13.5%) Indian and 76 (7.5%) Malay. Age-dependent MOF ITs ranged from 3.1 to 33%, 2.5 to 17% and 2.5 to 16% whilst HF ITs ranged from 0.7 to 17%, 0.4 to 6% and 0.4 to 6.3% in Chinese, Malay and Indian women, respectively, between the ages of 50 and 90 years. The weighted age-dependent MOF and HF ITs ranged from 2.9% and 0.6%, respectively, at the age of 50, to 28% and 14% at 90 years of age. Fixed MOF/HF ITs of 5.5%/1%, 2.5%/1% and 2.5%/0.25% were identified as the most optimal by the highest YI in Chinese, Malay and Indian women, respectively. Fixed MOFP and HF ITs of 4% and 1%, respectively, were found to be most optimal on the weighted means analysis. CONCLUSION: The ITs for osteoporosis treatment in Singapore show marked variations across ethnicities. Weighted mean thresholds may overcome the dilemma of intervening at different thresholds for different ethnicities. Choosing fixed ITs may have to involve trade-offs between sensitivity and specificity. FRAX®-based age-dependent or the fixed intervention thresholds suggested as an alternative to be considered for use in Singapore though further studies on the societal and health economic impacts of choosing these thresholds in Singapore are needed.


Assuntos
Povo Asiático/estatística & dados numéricos , Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Medição de Risco/estatística & dados numéricos , Índice de Gravidade de Doença , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/etnologia , Densidade Óssea , Conservadores da Densidade Óssea/uso terapêutico , Feminino , Fraturas do Quadril/etnologia , Fraturas do Quadril/etiologia , Fraturas do Quadril/prevenção & controle , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/etnologia , Fraturas por Osteoporose/etnologia , Fraturas por Osteoporose/etiologia , Pós-Menopausa , Fatores de Risco , Sensibilidade e Especificidade , Singapura
7.
Bone Joint J ; 100-B(5): 579-583, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29701098

RESUMO

Aims: This study investigated the influence of body mass index (BMI) on patients' function and quality of life ten years after total knee arthroplasty (TKA). Patients and Methods: A total of 126 patients who underwent unilateral TKA in 2006 were prospectively included in this retrospective study. They were categorized into two groups based on BMI: < 30 kg/m2 (control) and ≥ 30 kg/m2 (obese). Functional outcome was assessed using the Knee Society Function Score (KSFS), Knee Society Knee Score (KSKS), and Oxford Knee Score (OKS). Quality of life was assessed using the Physical (PCS) and Mental Component Scores (MCS) of the 36-Item Short-Form Health Survey. Results: Results Patients in the obese group underwent TKA at a younger age (mean, 63.0 years, sd 8.0) compared with the control group (mean, 65.6 years, sd 7.6; p = 0.03). Preoperatively, both groups had comparable functional and quality-of-life scores. Ten years postoperatively, the control group had significantly higher OKS and MCS compared with the obese group (OKS, mean 18 (sd 5) vs mean 22 (sd 10), p = 0.03; MCS, mean 56 (sd 10) vs mean 50 (sd 11), p = 0.01). After applying multiple linear regression with the various outcomes scores as dependent variables and age, gender, and Charlson Comorbidity Index as independent variables, there was a clear association between obesity and poorer outcome in KSFS, OKS, and MCS at ten years postoperatively (p < 0.01 in both KSFS and OKS, and p = 0.03 in MCS). Both groups had a high satisfaction rate (97.8% in the control group vs 87.9% in the obese group, p = 0.11) and fulfillment of expectations at ten years (98.9% in the control group vs 100% in the obese group, p = 0.32). Conclusion: Although both obese and non-obese patients have significant improvements in function and quality of life postoperatively, obese patients tend to have smaller improvements in the OKS and MCS ten years postoperatively. It is important to counsel patients on the importance of weight management to achieve a more sustained outcome after TKA. Cite this article: Bone Joint J 2018;100-B:579-83.


Assuntos
Artroplastia do Joelho , Obesidade/complicações , Osteoartrite do Joelho/cirurgia , Idoso , Índice de Massa Corporal , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/complicações , Qualidade de Vida , Recuperação de Função Fisiológica , Estudos Retrospectivos , Resultado do Tratamento
8.
Arch Osteoporos ; 13(1): 27, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29546650

RESUMO

Hospital care and mortality of diabetic and non-diabetic osteoporotic Asian patients undergoing hip fracture surgery were explored with no difference in length of hospitalization, incidence of post-operative complications, or mortality between diabetics and non-diabetics seen. Time to operation correlated with post-operative complications occurrence and therefore surgery should be expeditiously done. INTRODUCTION: Whether burden of inpatient care, problems after admission, and mortality rates differ between diabetics and non-diabetics undergoing surgery for osteoporotic hip fractures has not been explored in Asian populations. METHOD: Three hundred eighty-nine multi-ethnic diabetic and non-diabetic patients recruited into a FLS at a large Asian hospital with new osteoporotic hip fractures requiring operative repair were analyzed. RESULTS: 87.9% were Chinese, 6.4% Malay, and 3.6% Indians. BMI and age did not significantly differ between diabetics and non-diabetics. Median (IQR) length of hospitalization (LOHS) in days was 12 (9, 17) in diabetics and 11 (8, 14) in non-diabetics (p = 0.011). Median time from admission to operation (TTO) was 3 (2, 5) in diabetics versus 2 (1, 4.5) in the non-diabetics (p = 0.003). Occurrence of aggregate post-operative complications did not differ between diabetics and non-diabetics. No in-hospital mortalities occurred in either group. Thirty-day and 1-year mortality rates did not differ between the two groups. One-year mortality was 2.8% in the entire cohort. On multivariate regression analysis adjusted for age and race, only TTO (ß; 1.8, 95% CI 1.5-2.0, p < 0.001) and occurrence of post-operative complications (ß; 6.3, 95% CI 3.7-7.9, p < 0.001) correlated with LOHS. TTO and age-adjusted Charlson's Comorbidity Index (CCI) correlated significantly with the development of post-operative complications. CONCLUSIONS: Diabetes was not independently associated with LOHS in patients undergoing hip fracture surgery. Aggregate post-operative complications did not differ between diabetics and non-diabetics. TTO and occurrence of post-operative complications significantly affected LOHS. TTO correlated with post-complications development. Surgery should be expeditiously done in both diabetics and non-diabetics to avoid the development of post-operative complications and to prevent prolonged hospital stay.


Assuntos
Efeitos Psicossociais da Doença , Diabetes Mellitus/epidemiologia , Fraturas do Quadril , Fraturas por Osteoporose , Complicações Pós-Operatórias/mortalidade , Idoso , Idoso de 80 Anos ou mais , Sudeste Asiático , Estudos de Coortes , Feminino , Fraturas do Quadril/complicações , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/cirurgia , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Pacientes Internados , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Fraturas por Osteoporose/complicações , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/cirurgia , Avaliação de Processos e Resultados em Cuidados de Saúde
9.
J Oral Rehabil ; 45(1): 25-33, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28805272

RESUMO

Clinical and radiographic characteristics of a subset of South East Asian temporomandibular disorder (TMD) patients with comorbid upper airway resistance syndrome (UARS) were documented in a multi-center prospective series of 86 patients (26 men and 60 women / mean age 35.7 years). All had excessive daytime sleepiness, high arousal index and Apnoea-Hypopnoea Index (AHI) <5. The mean body mass index was 20·1, mean arousal index 16·2, mean respiratory disturbance index 19·6, mean AHI 3·9 while the mean Epworth Sleepiness Scale was 14·8. Many had functional somatic complaints; 66·3% headaches, 41·9% neck aches, 53·5% masticatory muscle myalgia, 68·6% temporomandibular joint (TMJ) arthralgia while 90·7% reported sleep bruxism (SB). Unlike patients with obstructive sleep apnoea (OSA), hypertension was uncommon (4·7%) while depression was prevalent at 68·6% with short REM latency of <90 min and an increased REM composition >25% documented in 79·6% and 57·6% of these depressed patients, respectively. 65·1% displayed a posteriorly displaced condyle at maximum intercuspation with or without TMJ clicking. Most exhibited a forward head posture (FHP) characterised by loss of normal cervical lordosis (80·2%), C0-C1 narrowing (38·4%) or an elevated hyoid position (50%), and 91·9% had nasal congestion. We postulate the TMD-UARS phenotype may have originally developed as an adaptive response to 'awake' disordered breathing during growth. Patients with persistent TMD and/or reporting SB should be screened for UARS and chronic nasal obstruction, especially when they also present with FHP. The lateral cephalogram is a useful tool in the differentiation of UARS from other OSA phenotypes.


Assuntos
Obstrução Nasal/diagnóstico por imagem , Bruxismo do Sono/diagnóstico por imagem , Transtornos do Sono-Vigília/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/fisiopatologia , Adulto , Resistência das Vias Respiratórias , Sudeste Asiático , Povo Asiático , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obstrução Nasal/fisiopatologia , Fenótipo , Estudos Prospectivos , Radiografia , Bruxismo do Sono/fisiopatologia , Transtornos do Sono-Vigília/fisiopatologia , Transtornos da Articulação Temporomandibular/complicações
10.
Bone Joint J ; 98-B(6): 780-5, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27235520

RESUMO

AIMS: This study investigated the influence of body mass index (BMI) on the post-operative fall in the level of haemoglobin (Hb), length of hospital stay (LOS), 30-day re-admission rate, functional outcome and quality of life, two years after total knee arthroplasty (TKA). PATIENTS AND METHODS: A total of 7733 patients who underwent unilateral primary TKA between 2001 and 2010 were included. The mean age was 67 years (30 to 90). There were 1421 males and 6312 females. The patients were categorised into three groups: BMI < 25.0 kg/m(2) (normal); BMI between 25.0 and 39.9 kg/m(2) (obese); and BMI ≥ 40.0 kg/m(2) (morbidly obese). RESULTS: Compared with the normal and obese groups, the mean LOS was longer by one day (95% confidence interval (CI) 0 to 2) in the morbidly obese group (p = 0.003 and p = 0.001 respectively). The 30-day re-admisison rate was also higher in the morbidly obese group compared to the obese group (OR 2.323, 95% CI 1.101 to 4.900, p = 0.024); and showed a higher trend compared to the normal group (OR 1.850, 95% CI 0.893 to 3.831, p = 0.100). However, the morbidly obese group had a smaller drop in post-operative Hb level by a mean of 0.5 g/dl (0.3 to 0.6) and 0.3 g/dl (0.1 to 0.5), when compared with the normal and obese groups respectively (both p < 0.001). Furthermore, the mean improvement in Oxford Knee Score (OKS) and Knee Society Knee Score (KSKS) at two years follow-up was three points (two to four) and five points (two to seven) more in the morbidly obese group than in the normal group (both p < 0.001). The mean improvement in Knee Society Function Score, and Physical and Mental Component Scores of Short Form-36 were comparable between the three BMI groups (p = 0.736, p = 0.739 and p = 0.731 respectively). The ten-year rate of survival was 98.8% (98.0 to 99.3), 98.9% (98.5 to 99.2) and 98.0% (95.8 to 100), for the normal, obese and morbidly obese groups, respectively (p = 0.703). CONCLUSION: Although morbidly obese patients have a longer LOS and higher 30-day re-admission rate after TKA, they have a smaller drop in post-operative Hb level and larger improvement in OKS and KSKS at two years follow-up. The ten-year rate of survival of TKA was also comparable with those with a normal BMI. TAKE HOME MESSAGE: Morbidly obese patients should not be excluded from the benefits of TKA. Cite this article: Bone Joint J 2016;98-B:780-5.


Assuntos
Artroplastia do Joelho , Índice de Massa Corporal , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Hemoglobinas/análise , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Obesidade Mórbida/epidemiologia , Readmissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias , Estudos Retrospectivos , Singapura/epidemiologia
11.
Bone Joint J ; 95-B(6): 788-92, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23723273

RESUMO

We prospectively followed 171 patients who underwent bilateral unicompartmental knee replacement (UKR) over a period of two years. Of these, 124 (72.5%) underwent a simultaneous bilateral procedure and 47 (27.5%) underwent a staged procedure. The mean cumulative operating time and length of hospital stay were both shorter in the simultaneous group, by 22.5 minutes (p < 0.001) and three days (p < 0.001), respectively. The mean reduction in haemoglobin level post-operatively was greater by 0.15 g/dl in the simultaneous group (p = 0.023), but this did not translate into a significant increase in the number of patients requiring blood transfusion (p = 1.000). The mean hospital cost was lower by $8892 in the simultaneous group (p < 0.001). There was no significant difference in the rate of complications between the groups, and at two-year follow-up there was no difference in the outcomes between the two groups. We conclude that simultaneous bilateral UKR can be recommended as an appropriate treatment for patients with bilateral medial compartment osteoarthritis of the knee.


Assuntos
Artroplastia do Joelho/métodos , Articulação do Joelho/fisiopatologia , Osteoartrite do Joelho/cirurgia , Amplitude de Movimento Articular/fisiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Articulação do Joelho/cirurgia , Tempo de Internação/tendências , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/fisiopatologia , Complicações Pós-Operatórias , Estudos Prospectivos , Resultado do Tratamento
12.
Mol Ecol ; 20(19): 3963-77, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21880085

RESUMO

We analysed a representative collection of New World sweet potato landraces (329 accessions from Mexico to Peru) with both chloroplast and nuclear microsatellite markers. Both kinds of markers supported the existence of two geographically restricted genepools, corresponding to accessions from the north-western part of South America and accessions from the Caribbean and Central America region. Our conservative cpSSRs markers revealed that the divergence between the two haplotype groups is associated with numerous mutation events concerning various markers, supporting the idea that this divergence may be ancient, predating domestication. For both kinds of markers, we found no significant difference in diversity between the two genepools and detected region-specific alleles in both groups. Previous studies have favoured the hypothesis of a single domestication of this crop. Our analysis suggests at least two independent domestications, in Central/Caribbean America and in the north-western part of South America. Sweet potato was then dispersed from these centres throughout tropical America. Comparison of nuclear and chloroplast data suggests that exchanges of clones and sexual reproduction were both important processes in landrace diversification in this clonally propagated crop. Our analysis provides useful tools for rationalizing the conservation and use of sweet potato germplasm collections.


Assuntos
Núcleo Celular/genética , Cloroplastos/genética , Ipomoea batatas/genética , Repetições de Microssatélites , Dispersão de Sementes , América Central , Variação Genética , Geografia , Haplótipos , Ipomoea batatas/fisiologia , México , Filogeografia , Dinâmica Populacional , América do Sul
13.
Cell Transplant ; 18(9): 1047-58, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20040141

RESUMO

Within the emerging field of stem cells there is a need for an environment that can regulate cell activity, to slow down differentiation or proliferation, in vitro or in vivo while remaining invisible to the immune system. By creating a nanoenvironment surrounding PC12 cells, Schwann cells, and neural precursor cells (NPCs), we were able to control the proliferation, elongation, differentiation, and maturation in vitro. We extended the method, using self-assembling nanofiber scaffold (SAPNS), to living animals with implants in the brain and spinal cord. Here we show that when cells are placed in a defined system we can delay their proliferation, differentiation, and maturation depending on the density of the cell population, density of the matrix, and the local environment. A combination of SAPNS and young cells can be implanted into the central nervous system (CNS), eliminating the need for immunosuppressants.


Assuntos
Diferenciação Celular/fisiologia , Nanotecnologia/métodos , Animais , Encéfalo/citologia , Diferenciação Celular/genética , Proliferação de Células , Cricetinae , Mesocricetus , Nanofibras , Neurônios/citologia , Células PC12/citologia , Ratos , Ratos Sprague-Dawley , Ratos Transgênicos , Células de Schwann/citologia , Medula Espinal/citologia , Engenharia Tecidual/métodos , Alicerces Teciduais/química
14.
Nat Protoc ; 1(4): 1898-905, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17487174

RESUMO

The dependence of visual orienting ability in hamsters on the axonal projections from retina to midbrain tectum provides experimenters with a good model for assessing the functional regeneration of this central nervous system axonal pathway. For reliable testing of this behavior, male animals at least 10-12 weeks old are prepared by regular pretesting, with all procedures carried out during the less active portion of the daily activity cycle. Using a sunflower seed attached to a small black ball held at the end of a stiff wire, and avoiding whisker contact, turning movements toward visual stimuli are video recorded from above. Because at the eye level, the nasal-most 30 degrees of the visual field can be seen by both the eyes, this part of the field is avoided in assessments of a single side. Daily sessions consist of ten presentations per side. Measures are frequency of responding and detailed turning trajectories. Complete assessment of the functional return of behavior in this testing paradigm takes 3-6 months to complete.


Assuntos
Comportamento Apetitivo/fisiologia , Testes Neuropsicológicos , Testes Visuais/veterinária , Visão Ocular/fisiologia , Percepção Visual/fisiologia , Animais , Cricetinae , Masculino , Mesocricetus
15.
Prikl Biokhim Mikrobiol ; 40(4): 442-7, 2004.
Artigo em Russo | MEDLINE | ID: mdl-15455717

RESUMO

Addition of iron (III) hydroxide during methanogenic digestion of active sludge by anaerobic sludge displaying an iron-reducing activity resulted in a microbial reduction of iron (III) with formation of iron (II), capable of precipitating phosphates. Feasibility of eliminating 66.6 to 99.6% of dissolved phosphate at initial concentrations of 1000 to 3500 mg PO4(3-)/l by adding 6420 mg/l iron (III) hydroxide into a reactor for anaerobic fermentation of active sludge. The optimal ratio of iron (III) added to dissolved phosphate eliminated (mg) providing a 95% elimination amounted to 2:1. These results may be used in a new technology for anaerobic wastewater treatment with phosphate elimination.


Assuntos
Bactérias Anaeróbias/metabolismo , Fosfatos/análise , Esgotos/microbiologia , Bactérias Anaeróbias/efeitos dos fármacos , Biodegradação Ambiental/efeitos dos fármacos , Reatores Biológicos/microbiologia , Compostos Férricos/farmacologia , Methanomicrobiaceae/metabolismo , Esgotos/química
16.
Neurochem Res ; 29(11): 2153-61, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15662850

RESUMO

This study examined the relationship between the distance of axotomy and the death of injured retinal ganglion cells (RGCs) in adult hamsters and the relationship of cytochrome c and caspase-3 on the death pathway of RGCs. The left optic nerve (ON) of adult hamsters was transected either at 1 or 3 mm away from the optic disc, and retrogradely labeled with Flurogold on the ON stump. After a predetermined period of postoperative time, the surviving RGCs were counted by retina flat-mount, and the activation of cytochrome c and caspase-3 were investigated by immunohistochemistry. Cell loss was found to be much faster (P < 0.01), more cells with cytochrome c were observed (P < 0.05) and the activation of caspase-3 was earlier when ON was transected 1 mm away from the optic disc than when was transected 3 mm away from the optic disc. Distance of axotomy affects the axotomized cell death rate where more RGCs died when the ON transection was applied closer to the eye. The timing of activation of caspase-3 in the RGCs may be linked to the distance of axotomy.


Assuntos
Axotomia , Caspases/metabolismo , Citocromos c/metabolismo , Nervo Óptico/fisiologia , Células Ganglionares da Retina/enzimologia , Animais , Caspase 3 , Sobrevivência Celular/fisiologia , Cricetinae , Fragmentação do DNA , Ativação Enzimática/fisiologia , Imuno-Histoquímica , Masculino , Mesocricetus
17.
Connect Tissue Res ; 44(1): 2-11, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12945799

RESUMO

This study compared the collagen fibril diameter distribution among six anatomical sites of the rat medial collateral ligament (MCL). Ultrathin MCL sections from 4 male Sprague-Dawley rats were examined electron microscopically. With an automated quantitation method, 41,638 fibrils were measured and compared among the periphery and core regions of the femoral, middle, and tibial portions of the MCL. Results demonstrated significant difference (p < .0033) in mean fibril diameter distribution among the six sites. The mass-averaged diameters of the core and peripheral fibrils were between 175.53 to 190.82 nm and 88.47 to 109.18 nm, respectively, with the peripheral fibrils more homogeneous in size. The fibrils occupied 36.7% to 57.1% of the cross-sectional area of the ligament. About 50% of the fibrils had an oblique factor of 0.8-1.0, implying that most fibrils were aligned longitudinally. This study has provided a detailed profile of the collagen fibril distributions in rat MCL.


Assuntos
Ligamentos Colaterais/metabolismo , Colágenos Fibrilares/metabolismo , Membro Posterior/metabolismo , Animais , Ligamentos Colaterais/ultraestrutura , Colágenos Fibrilares/ultraestrutura , Membro Posterior/ultraestrutura , Processamento de Imagem Assistida por Computador , Masculino , Microscopia Eletrônica de Varredura , Modelos Animais , Ratos , Ratos Sprague-Dawley
18.
J Neurocytol ; 29(2): 91-7, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11068337

RESUMO

The time course of c-jun expression and the effect of a peripheral nerve (PN) graft on axonal regeneration and c-jun expression in the lateral vestibular nucleus (LVN) were investigated in this study. c-Jun was found in LVN neurons 1 day after hemisection of the spinal cord at C3, with weak immunoreactivity. Strong c-Jun positive immunoreactivity was found 3 days post-injury. The expression of c-jun reached its maximum level (45% +/- 2.5, mean +/- SD) 1 week post-injury and gradually decreased to about a third of its peak value 6 weeks after the inflicted lesion. The PN graft implanted at the lesion site significantly enhanced the number of neurons expressing c-jun 4 weeks after PN transplantation (from 20% of LVN neurons in axotomy alone to 30% in PN graft transplantation, P < 0. 05). The PN graft induced injured neurons to regrow into the PN graft. About 91 FG-labeled neurons were found in the LVN and approximately 87% of these neurons showed c-Jun positive immunoreactivity. The high percentage of regenerating neurons expressing c-jun suggested that c-Jun might be involved in the regenerative process. The result of double staining for c-Jun and NOS showed that approximately 93% NOS positive neurons co-expressed c-Jun. Comparing the time course of the appearance of c-Jun with that of NOS, the expression of c-jun preceded that of NOS. Although a high percentage of NOS reactive neurons expressed c-jun, the expression of NOS in damaged LVN neurons needs to be further investigated.


Assuntos
Proteínas Proto-Oncogênicas c-jun/biossíntese , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/cirurgia , Nervo Tibial/transplante , Núcleo Vestibular Lateral/metabolismo , Fatores Etários , Animais , Feminino , Regeneração Nervosa/fisiologia , Neurônios/química , Neurônios/enzimologia , Óxido Nítrico Sintase/análise , Óxido Nítrico Sintase/biossíntese , Proteínas Proto-Oncogênicas c-jun/análise , Ratos , Ratos Sprague-Dawley , Núcleo Vestibular Lateral/química , Núcleo Vestibular Lateral/citologia
19.
FEBS Lett ; 482(1-2): 37-43, 2000 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-11018519

RESUMO

We cloned a major isoform of Xenopus homologue of cold inducible RNA binding protein (CIRP), XCIRP-1. XCIRP-1 was neither cold inducible nor essential for cell division during early embryonic development. Suppression of XCIRP-1 dose dependently produced tailbuds with deformations of the brain and internal organs. The defects were XCIRP-1 specific as they could be rescued by sense transcript. Suppression of XCIRP-1 also disrupted the morphogenetic migration of the C3 blastomeres (lineaged to become the embryonic kidney, the pronephros). In animal cap explants, depletion of XCIRP-1 inhibited activin/retinoic acid induced expressions of pronephros related Xlim-1 and WT1 genes. These results suggest that XCIRP-1 is required for the specification and morphogenetic lineage migration of the pronephros.


Assuntos
Rim/embriologia , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteínas de Xenopus , Xenopus laevis/embriologia , Anormalidades Múltiplas/genética , Animais , Divisão Celular , Clonagem Molecular , Embrião não Mamífero/fisiologia , Evolução Molecular , Feminino , Rim/citologia , Morfogênese , Fenótipo , Filogenia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Supressão Genética , Transcrição Gênica , Xenopus laevis/genética
20.
Can J Anaesth ; 45(7): 620-5, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9717591

RESUMO

PURPOSE: To compare the effect of a combination of intrathecal (i.t.) sufentanil plus bupivacaine with i.t. sufentanil alone, on the incidence of hypotension and the success of ambulation in parturients. METHODS: This was a controlled, double-blind prospective trial involving 50 parturients in early labour who had received combined spinal-epidural analgesia (CSE). They were divided equally into two groups; group A received 10 micrograms i.t. sufentanil while group B received i.t. 10 micrograms sufentanil plus 2.5 mg plain bupivacaine. The blood pressure, pain scores, the highest sensory block and the degree of motor blockade were documented over the first 30 min by an unbiased anaesthetist. The ability and the desire to ambulate was studied 30 min after CSE. The side effects were documented throughout labour. RESULTS: Group B had a higher incidence of hypotension; (12 vs 3: P < 0.01). Fewer parturients in group B could ambulate (19 vs 25: P < 0.05). Group B also had a higher sensory blockade than group A (median T4 VS T7-8: P < 0.01). Of all the 44 parturients who could ambulate, 13 desired not to do so, usually due to sedation. CONCLUSION: The quality of analgesia in all subjects in the study was excellent. Side effects were more common in the i.t. sufentanil-bupivacaine combination group.


Assuntos
Analgesia Epidural , Analgesia Obstétrica , Raquianestesia , Anestésicos Intravenosos , Sufentanil , Anestésicos Combinados/administração & dosagem , Anestésicos Combinados/efeitos adversos , Anestésicos Intravenosos/administração & dosagem , Bupivacaína/efeitos adversos , Método Duplo-Cego , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Hipotensão/induzido quimicamente , Injeções Espinhais , Trabalho de Parto/efeitos dos fármacos , Gravidez , Estudos Prospectivos , Sufentanil/administração & dosagem , Caminhada
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