RESUMEN
Mesenchymal stromal cells (MSCs) have therapeutic potential due to their abilities of differentiation, immunomodulation, and migration to injured tissues, potentiating such effects when cells are activated. Guarana (Paullinia cupana) is a tropical plant species found in South America that is known for its antioxidant, stimulant, and cicatricial effects. The guarana extract is composed of many substances and caffeine is the main component. The objective was to evaluate the effects of guarana and caffeine on MSCs. After the initial characterization, MSCs were treated with Paullinia cupana (10, 100, and 1000 µg/mL) or caffeine (0.4, 4, and 40 µg/mL) for 24 h. MSCs treatment with 1000 µg/mL guarana increased cell polarity, viability, cell migration to chemoattractant, antioxidant potential, and liberation of extracellular vesicles (EVs), while it reduced the levels of autophagy. MSCs treated with 100 and 1000 µg/mL guarana or 40 µg/mL caffeine showed a decrease of cell proliferation. No treatment affected the cellular area and cell cycle of MSCs. The study shows in vitro evidence that guarana could be a promising alternative for activating MSCs to promote better cellular products for future clinical therapies.
Asunto(s)
Proliferación Celular , Células Madre Mesenquimatosas , Paullinia , Extractos Vegetales , Medicina Regenerativa , Paullinia/química , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/citología , Extractos Vegetales/farmacología , Proliferación Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cafeína/farmacología , Células Cultivadas , Diferenciación Celular/efectos de los fármacos , Antioxidantes/farmacología , Humanos , AnimalesRESUMEN
PURPOSE: This study aimed to verify the association between dental pain and severity of dental caries (caries morbidity stages) and the impact on oral health-related quality of life (OHRQoL) in preschool children. METHODS: A cross-sectional study with 199 children (2-5 years old) enrolled at preschools in Capão do Leão-RS, Brazil. The self-report of mothers of children with a history of dental pain in the last 6 months and perception of their child's OHRQoL (ECOHIS) were obtained through a structured questionnaire. This questionnaire also collected independent variables. Children's oral examination was performed using the CAST instrument to determine caries morbidity stage. Crude and adjusted Poisson regression analysis was performed. RESULTS: The prevalence of dental pain was 14.57%. The chance of the occurrence of dental pain was higher among children diagnosed in morbidity [Prevalence ratio-PR: 5.29 (95% confidence interval-95% CI 1.91-14.61); p = 0.001] and severe morbidity [RP = 6.12 (95 CI% 2.25-16.64); p < 0.001] stages. Children with dental pain presented higher scores in the total ECOHIS [rate ratio = 7.11 (95% CI 4.55-11.09); p < 0.001] and in all of the domains of this instrument. Furthermore, children with a history of dental trauma [PR = 2.41 (95% CI 1.15-5.04); p < 0.001] and those whose reason for last visit to the dental office was for restorative/endodontic/extraction treatment [PR = 1.29 (95% CI 1.01-6.19); p = 0.049] had a higher prevalence of dental pain. CONCLUSION: A substantial prevalence of dental pain in the last 6 months and negative impact on children's OHRQoL was identified in this sample. Children diagnosed with carious dentin lesions and abscess and fistula were more likely to have dental pain.
Asunto(s)
Caries Dental , Salud Bucal , Calidad de Vida , Odontalgia , Humanos , Caries Dental/epidemiología , Caries Dental/complicaciones , Brasil/epidemiología , Preescolar , Estudios Transversales , Femenino , Masculino , Odontalgia/epidemiología , Prevalencia , Encuestas y Cuestionarios , Índice de Severidad de la EnfermedadRESUMEN
PURPOSE: The purpose of this study was to gather existing data on the efficacy of tooth splinting (TS) in patients with traumatized primary teeth, evaluating their overall prognosis and reported complications. METHODS: Electronic searches were performed in seven databases up to Februray/2023. Clinical studies published in the last two decades and presenting the following characteristics were included: (a) reporting on children with traumatized primary teeth; (b) describing the efficacy of splinting those teeth. Studies describing imobilization of dental avulsion were excluded. RESULTS: A total of 163 potentially relevant studies were initially found. After title/abstract screening, and full-text evaluation, three retrospective studies with moderate to high risk of bias were included. The studies described the outcomes of TS in primary teeth with luxation (intrusion, extrusion, lateral displacement), intra-alveolar root fracture, and/or alveolar fracture. High clinical success rate was observed for teeth with root fracture. Benefits of spliting teeth with lateral luxation were not identified, although it may be a reccomended approach. No study was found evaluating TS for alveolar fracture. CONCLUSION: Based on a low level of evidence, the findings highlight a better clinical success rate of the use of TS in the management of deciduous teeth with root fractures.
Asunto(s)
Avulsión de Diente , Fracturas de los Dientes , Niño , Humanos , Avulsión de Diente/terapia , Estudios Retrospectivos , Raíz del Diente/lesiones , Fracturas de los Dientes/terapia , Diente PrimarioRESUMEN
Glioblastoma (GB) is the most common and aggressive form of primary brain tumor, in which the presence of an inflammatory environment, composed mainly by tumor-associated macrophages (TAMs), is related to its progression and development of chemoresistance. Toll-Like Receptors (TLRs) are key components of the innate immune system and their expression in both tumor and immune-associated cells may impact the cell communication in the tumor microenvironment (TME), further modeling cancer growth and response to therapy. Here, we investigated the participation of TLR4-mediated signaling as a mechanism of induced-immune escape in GB. Initially, bioinformatics analysis of public datasets revealed that TLR4 expression is lower in GB tumors when compared to astrocytomas (AST), and in a subset of TAMs. Further, we confirmed that TLR4 expression is downregulated in chemoresistant GB, as well as in macrophages co-cultured with GB cells. Additionally, TLR4 function is impaired in those cells even following stimulation with LPS, an agonist of TLR4. Finally, experiments performed in a cohort of clinical primary and metastatic brain tumors indicated that the immunostaining of TLR4 and CD45 are inversely proportional, and confirmed the low TLR4 expression in GBs. Interestingly, the cytoplasmic/nuclear pattern of TLR4 staining in cancer tissues suggests additional roles of this receptor in carcinogenesis. Overall, our data suggest the downregulation of TLR4 expression and activity as a strategy for GB-associated immune escape. Additional studies are necessary to better understand TLR4 signaling in TME in order to improve the benefits of immunotherapy based on TLR signaling.
Asunto(s)
Neoplasias Encefálicas/inmunología , Regulación hacia Abajo/inmunología , Glioblastoma/inmunología , Glioblastoma/metabolismo , Evasión Inmune/inmunología , Receptor Toll-Like 4/inmunología , Macrófagos Asociados a Tumores/inmunología , Anciano , Animales , Neoplasias Encefálicas/metabolismo , Línea Celular , Línea Celular Tumoral , Proliferación Celular/fisiología , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Transducción de Señal/inmunología , Receptor Toll-Like 4/metabolismo , Microambiente Tumoral/inmunología , Macrófagos Asociados a Tumores/metabolismoRESUMEN
OBJECTIVE: To compare four enzymatic protocols for mesenchymal stem cells (MSCs) isolation from amniotic (A-MSC) and chorionic (C-MSC) membranes, umbilical cord (UC-MSC) and placental decidua (D-MSC) in order to define a robust, practical and low-cost protocol for each tissue. RESULTS: A-MSCs and UC-MSCs could be isolated from all samples using trypsin/collagenase-based protocols; C-MSCs could be isolated from all samples with collagenase- and trypsin/collagenase-based protocols; D-MSCs were isolated from all samples exclusively with a collagenase-based protocol. CONCLUSIONS: The trypsin-only protocol was least efficient; the collagenase-only protocol was best for C-MSCs and D-MSCs; the combination of trypsin and collagenase was best for UC-MSCs and none of tested protocols was adequate for A-MSCs isolation.
Asunto(s)
Separación Celular/métodos , Membranas Extraembrionarias/citología , Células Madre Mesenquimatosas/citología , Placenta/citología , Cordón Umbilical/citología , Proliferación Celular , Células Cultivadas , Colagenasas , Femenino , Humanos , Cinética , Embarazo , TripsinaRESUMEN
OBJECTIVES: Oxidative stress is considered a risk factor for physical function (PF) decline with aging. The objective of this study was to examine the relationship between antioxidant intake and change in PF over a 5-year period. DESIGN, SETTING, PARTICIPANTS: The Boston Area Community Health (BACH) Survey is a population-based longitudinal study including 5,502 racially/ethnically diverse and randomly selected participants aged 30-79 years. MEASUREMENTS: In total, 2828 persons aged 30-79 years completed the validated Block Food Frequency Questionnaire (FFQ) and participated in the follow-up study. Change in PF from baseline (2002-2005) to follow-up (2006-2010) was assessed using the validated SF-12 questionnaire. Linear models were used to examine the association between energy-adjusted quartiles of vitamins C, E and carotenoids and change in PF. RESULTS: A low intake (first quartile) of vitamin E was associated with a greater decline in PF compared with the highest quartile, with a mean difference in change in PF of -1.73 (95%CI:-3.31,-0.15). Notably, this mean difference was clinically meaningful as it was equivalent to the effect estimate we found for participants who were approximately 15 years apart in age in our cohort, as 1 year increase in age was associated with a mean difference in change in PF of -0.11 (95%CI:-0.16,-0.06). PF decline was not significantly different in the lowest compared with the highest quartile of vitamin C (mean difference=-1.29, 95%CI:-2.61, 0.03) or carotenoids (mean difference=-0.62, 95%CI:-2.22,0.99). CONCLUSIONS: Low intake of vitamin E was significantly associated with decline in PF with aging. These results are clinically meaningful, extend previous findings that oxidative stress contributes to PF decline, and may inform the development of future prevention strategies aimed at reducing this clinical and public health problem.
Asunto(s)
Envejecimiento/efectos de los fármacos , Envejecimiento/fisiología , Antioxidantes/farmacología , Dieta/estadística & datos numéricos , Etnicidad , Grupos Raciales , Vitamina E/farmacología , Adulto , Anciano , Antioxidantes/administración & dosificación , Ácido Ascórbico/administración & dosificación , Ácido Ascórbico/farmacología , Boston , Carotenoides/administración & dosificación , Carotenoides/farmacología , Encuestas sobre Dietas , Femenino , Estudios de Seguimiento , Estado de Salud , Encuestas Epidemiológicas , Humanos , Modelos Lineales , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Estrés Oxidativo/efectos de los fármacos , Reproducibilidad de los Resultados , Vitamina E/administración & dosificaciónRESUMEN
Bone mineral density, muscle mass and physical function reach their peak between the second and fourth decade of life and then decline steadily with aging. The crucial question is: what factors contribute to or modulate this decline? The aim of this mini-review is to propose a theoretical framework for the potential role of emerging biomarkers such as klotho, fibroblast growth factors (FGF)21 and FGF23 on musculoskeletal health, with a particular focus on decline in muscle mass and function, and calls for future research to examine this proposed link. The identification of new physiological mechanisms underlying these declines may open a potentially important avenue for the development of novel intervention strategies aimed at preventing or reducing their potentially detrimental consequences.
RESUMEN
UNLABELLED: People with both HIV and hepatitis C are more likely than those with HIV alone to have wrist, hip, and spine fractures. We compared hip strength between HIV/HCV-co-infected men and healthy men and found that HIV/HCV-co-infected men had decreased hip strength due to lower lean body mass. INTRODUCTION: Hepatitis C co-infection is a risk factor for fragility fracture among HIV-infected populations. Whether bone strength is compromised in HIV/HCV-co-infected patients is unknown. METHODS: We compared dual-energy x-ray absorptiometry (DXA)-derived hip geometry, a measure of bone strength, in 88 HIV/HCV-co-infected men from the Johns Hopkins HIV Clinic to 289 men of similar age and race and without HIV or HCV from the Boston Area Community Health Survey/Bone Survey. Hip geometry was assessed at the narrow neck, intertrochanter, and shaft using hip structural analysis. Lean body mass (LBM), total fat mass (FM), and fat mass ratio (FMR) were measured by whole-body DXA. Linear regression was used to identify body composition parameters that accounted for differences in bone strength between cohorts. RESULTS: HIV/HCV-co-infected men had lower BMI, LBM, and FM and higher FMR compared to controls (all p < 0.05). At the narrow neck, significant differences were observed between HIV/HCV-co-infected men and controls in bone mineral density, cross-sectional area, section modulus, buckling ratio, and centroid position. After adjustment for race, age, smoking status, height, and weight, only buckling ratio and centroid position remained significantly different between cohorts (all p < 0.05). Substituting LBM, FM, and FMR for weight in the multivariate model revealed that differences in LBM, but not FM or FMR, accounted for differences in all narrow neck parameters between cohorts, except buckling ratio and centroid position. CONCLUSION: HIV/HCV-co-infected men have compromised hip strength at the narrow neck compared to uninfected controls, which is attributable in large part to lower lean body mass.
Asunto(s)
Infecciones por VIH/complicaciones , Hepatitis C/complicaciones , Articulación de la Cadera/patología , Absorciometría de Fotón , Adulto , Anciano , Composición Corporal , Densidad Ósea , Estudios de Casos y Controles , Estudios Transversales , Articulación de la Cadera/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
It was hypothesized the lower fertility of repeat-breeder (RB) Holstein cows is associated with oocyte quality and this negative effect is enhanced during summer heat stress (HS). During the summer and the winter, heifers (H; n=36 and 34, respectively), peak-lactation (PL; n=37 and 32, respectively), and RB (n=36 and 31, respectively) Holstein cows were subjected to ovum retrieval to assess oocyte recovery, in vitro embryonic developmental rates, and blastocyst quality [terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive cells and total cell number]. The environmental temperature and humidity, respiration rate, and cutaneous and rectal temperatures were recorded in both seasons. The summer HS increased the respiration rate and the rectal temperature of PL and RB cows, and increased the cutaneous temperature and lowered the in vitro embryo production of Holstein cows and heifers. Although cleavage rate was similar among groups [H=51.7% ± 4.5 (n=375), PL=37.9% ± 5.1 (n=390), RB=41.9% ± 4.5 (n=666)], blastocyst rate was compromised by HS, especially in RB cows [H=30.3% ± 4.8 (n=244) vs. 23.3% ± 6.4 (n=150), PL=22.0% ± 4.7 (n=191) vs. 14.6% ± 7.6 (n=103), RB=22.5% ± 5.4 (n=413) vs. 7.9% ± 4.3 (n=177)]. Moreover, the fragmentation rate of RB blastocysts was enhanced during the summer, compared with winter [4.9% ± 0.7 (n=14) vs. 2.2% ± 0.2 (n=78)] and other groups [H=2.5% ± 0.7 (n=13), and PL=2.7% ± 0.6 (n=14)] suggesting that the association of RB fertility problems and summer HS may potentially impair oocyte quality. Our findings provide evidence of a greater sensitivity of RB oocytes to summer HS.
Asunto(s)
Enfermedades de los Bovinos/fisiopatología , Fertilidad/fisiología , Trastornos de Estrés por Calor/veterinaria , Calor/efectos adversos , Oocitos/fisiología , Estaciones del Año , Animales , Blastocisto/fisiología , Bovinos , Femenino , Trastornos de Estrés por Calor/fisiopatología , Oocitos/crecimiento & desarrollo , Embarazo , Índice de EmbarazoRESUMEN
UNLABELLED: The relative importance of various contributors to racial/ethnic variation in BMC/BMD is not established. Using population-based data, we determined that body composition differences (specifically skeletal muscle and fat mass) are among the strongest contributors to these variations. INTRODUCTION: Racial/ethnic variation in fracture risk is well documented, but the mechanisms by which such heterogeneity arises are poorly understood. We analyzed data from black, Hispanic, and white men enrolled in the Boston Area Community Health/Bone (BACH/Bone) Survey to determine the contributions of risk factors to racial/ethnic differences in bone mineral content (BMC) and density (BMD). METHODS: In a population-based study, BMC, BMD, and body composition were ascertained by DXA. Socioeconomic status, health history, and dietary intake were obtained via interview. Hormones and markers of bone turnover were obtained from non-fasting blood samples. Multivariate analyses measured percentage reductions in estimated racial/ethnic differences in BMC/BMD, accompanying the successive removal of covariates from linear regression models. RESULTS: Black men demonstrated greater BMC than their Hispanic and white counterparts. At the femoral neck, adjustment for covariables was sufficient to reduce these differences by 46% and 35%, respectively. While absolute differences in BMC were smaller at the distal radius than femoral neck, the proportionate reductions in racial/ethnic differences after covariable adjustment were comparable or greater. Multivariate models provided evidence that lean and fat mass, serum 25(OH)D, osteocalcin, estradiol, and aspects of socioeconomic status influence the magnitude of racial/ethnic differences in BMC, with lean and fat mass providing the strongest effects. Results for BMD were similar, but typically of lesser magnitude and statistical significance. CONCLUSIONS: These cross-sectional analyses demonstrate that much of the racial/ethnic heterogeneity in measures of bone mass and density can be accounted for through variation in body composition, diet, and socio-demographic factors.
Asunto(s)
Población Negra , Densidad Ósea/fisiología , Hispánicos o Latinos , Población Blanca , Absorciometría de Fotón , Adulto , Anciano , Andrógenos/sangre , Composición Corporal/fisiología , Estudios Transversales , Estrógenos/sangre , Cuello Femoral/diagnóstico por imagen , Estado de Salud , Humanos , Estilo de Vida/etnología , Masculino , Persona de Mediana Edad , Radio (Anatomía)/diagnóstico por imagen , Factores de Riesgo , Factores SocioeconómicosAsunto(s)
Humanos , Animales , Anopheles , Anopheles/crecimiento & desarrollo , Malaria , Malaria/prevención & controlAsunto(s)
Humanos , Animales , Anopheles , Anopheles/crecimiento & desarrollo , Malaria , Malaria/prevención & controlRESUMEN
SUMMARY: Focus on individual risk factors for osteoporosis could allocate disproportionate attention to trivial relationships. We tested many recognized risk factors of osteoporosis for their association with bone mineral density (BMD) in multivariate models among men. Lean mass accounted for the most variance, with substantially less accounted for by demographic, strength, and health factors. INTRODUCTION: Osteoporosis in men has gained recognition as a public health problem, generating an interest in the search for risk factors. Isolation of individual risk factors could allocate disproportionate attention to relationships that may be of limited consequence. METHODS: The Boston Area Community Health/Bone (BACH/Bone) Survey is a population-based study of randomly selected community-dwelling men (age, 30-79 years). BMD and lean mass were measured by dual X-ray absorptiometry. Socioeconomic status, health history, and lifestyle factors were obtained via interview. Hormone levels and markers of bone turnover were obtained from non-fasting blood samples. Multivariate analyses measured relative contributions of covariates to femoral neck (hip), one-third distal radius (wrist), and lumbar spine BMD. RESULTS: Factors positively associated with BMD in multivariate models at the three sites were black race and appendicular lean mass. Asthma was consistently negatively associated. Various other risk factors also contributed significantly to each of the individual sites. R (2) values for the hip, wrist, and spine were 41%, 30%, and 24%, respectively. Lean mass accounted for the most explained variance at all three sites. CONCLUSIONS: These data emphasize the limitation of focusing on individual risk factors and highlight the importance of potentially modifiable lean mass in predicting BMD.
Asunto(s)
Densidad Ósea/fisiología , Osteoporosis/etiología , Absorciometría de Fotón/métodos , Adulto , Anciano , Biomarcadores/sangre , Composición Corporal , Métodos Epidemiológicos , Cuello Femoral/fisiopatología , Humanos , Estilo de Vida , Vértebras Lumbares/fisiopatología , Masculino , Massachusetts/epidemiología , Persona de Mediana Edad , Osteoporosis/epidemiología , Osteoporosis/fisiopatología , Radio (Anatomía)/fisiopatología , Clase SocialRESUMEN
In this work, hybrid chitosan/hydroxyapatite composites material were developed and characterized. The polymer matrix was first dissolved in polylactic acid, and then hydroxyapatite (HA) was added as filler material. The effects of the added amounts of a crosslinking agent (genipin) and of the concentrations of lactic acid, and of the presence of HA powder on the evolution of rheological properties were evaluated. A significant decrease of gelation time with increasing amounts of crosslinking agent was observed, the effect being even more pronounced in the presence of HA. The chitosan matrix and the composites with a chitosan/HA weight ratio of 2/5 were characterized using microstructural analysis and in vitro tests. The formation of large pore sizes in the chitosan-based scaffolds was favored by low concentrations of lactic acid and genipin. The in vitro tests in synthetic body fluid revealed an extensive formation of an apatitic layer onto the surface of the chitosan/HA composite scaffolds crosslinked with genipin.
Asunto(s)
Materiales Biocompatibles/química , Quitosano/química , Durapatita/química , Ácido Láctico/química , Polímeros/química , Líquidos Corporales/química , Reactivos de Enlaces Cruzados/química , Elasticidad , Glicósidos Iridoides , Iridoides/química , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Poliésteres , Porosidad , Reología , Propiedades de Superficie , Andamios del Tejido/química , ViscosidadRESUMEN
UNLABELLED: There are few data on the skeletal health of Hispanic men. We observed differences in vitamin D deficiency and low BMD between Hispanic ethnic subgroups that persisted with adjustment for risk factors. Our data indicate a substantial burden of low BMD and vitamin D deficiency among Hispanic men. INTRODUCTION: Disparities within ethnic groups are generally ignored, but in evolving populations they may have implications for public health. We examined ethnic variation in serum 25-hydroxyvitamin D [25(OH)D] and bone mineral density (BMD) among Hispanic American men. METHODS: Three hundred and fifty-eight Hispanic males 30 to 79 years of age were studied. Logistic regression models assessed variation in odds of vitamin D deficiency (<20 ng/mL) and low BMD (T-score<-1) by ethnicity, with and without adjustment for risk factors (age, smoking, occupation, physical activity, body mass index, and sunlight exposure). RESULTS: Vitamin D deficiency was most common among Puerto Rican (26%), compared with Dominican (21%), Central American (11%), and South American (9%) men. Percentages with low BMD were: South American (44%), Puerto Rican (34%), Dominican (29%), and Central American (23%). Adjustment for age and risk factors failed to account for Hispanic subgroup differences in vitamin D deficiency and low BMD. Population estimates indicate a substantial burden of low BMD and vitamin D deficiency among Hispanic men. CONCLUSIONS: Our findings underscore the importance of examining the skeletal health of Hispanic subgroups, and suggest that a considerable number of Hispanic men may be at elevated risk of fracture and vitamin D deficiency.
Asunto(s)
Hispánicos o Latinos , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/etnología , Vitamina D/análogos & derivados , Adulto , Anciano , Biomarcadores/sangre , Densidad Ósea , Estudios Transversales , Fracturas Óseas/etiología , Humanos , Modelos Logísticos , Masculino , Massachusetts , Persona de Mediana Edad , Prevalencia , Riesgo , Vitamina D/sangre , Deficiencia de Vitamina D/fisiopatologíaRESUMEN
Trypanosoma cruzi, the causal agent of Chagas' Disease, is a widely spread protozoa in America. Blood transfusion is the secondly most important way of acquiring the infection. In blood banks, tests are performed to eliminate potentially infected blood. This study aimed to evaluate the positivity for T. cruzi in blood samples of donor's candidates in Southern Brazil. The study was based on a sampling containing all blood donors of Hemopel - a Pelotas City Blood Center, Rio Grande do Sul State, Brazil, from 2004 to 2005. Serological study was performed using ELISA Chagatest. Sampling containing values ± 20 percent cut off were evaluated using ELISA Chagatek, ELISA Alka/Adaltis, IHA Chagatest and IIF Imunocruzi. TESA-Blot was used as a confirmatory procedure in situations where blood samples showed conflicting results. From 4,482 samples collected in 2004 and 2005, the reactivity for anti-T. cruzi was 0.96 percent (43). Among those, 21 cases (0.47 percent) were confirmed as positive - most of them were female, with low school level and averaging 47.2 percent years old. Interestingly, the blood donors are not aware of being contaminated and this fact makes it difficult for controlling the disease. Chagas' Disease was one of the main reasons for discarding blood bags through serological control in Southern Brazil. Sampling reactivity showed variation among the different techniques used for anti-T. cruzi research. In order to obtaining more secure and conclusive results, more than one diagnostic technique must be used.
Asunto(s)
Adulto , Animales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Anticuerpos Antiprotozoarios/sangre , Donantes de Sangre/estadística & datos numéricos , Enfermedad de Chagas/epidemiología , Trypanosoma cruzi/inmunología , Brasil/epidemiología , Enfermedad de Chagas/diagnóstico , Ensayo de Inmunoadsorción Enzimática , Adulto JovenRESUMEN
UNLABELLED: We examined BMC and body composition in 1,209 black, Hispanic, and white men. Weight, BMI, waist circumference, and fat mass were associated with BMC only up to certain thresholds, whereas lean mass exhibited more consistent associations. The protective influence of increased weight appears to be driven by lean mass. INTRODUCTION: Reduced body size is associated with decreased bone mass and increased fracture risk, but associations in men and racially/ethnically diverse populations remain understudied. We examined bone mineral content (BMC) at the hip, spine, and forearm as a function of body weight, body mass index (BMI), waist circumference, fat mass (FM), and nonbone lean mass (LM). METHODS: The design was cross-sectional; 363 non-Hispanic black, 397 Hispanic, and 449 non-Hispanic white residents of greater Boston participated (N = 1,209, ages 30-79 y). BMC, LM, and FM were measured by DXA. Multiple linear regression was used to describe associations. RESULTS: Weight, BMI, waist circumference, and FM were associated with BMC only up to certain thresholds. LM, by contrast, displayed strong and consistent associations; in multivariate models, femoral neck BMC exhibited a 13% increase per 10 kg cross-sectional increase in LM. In models controlling for LM, positive associations between BMC and other body composition measures were eliminated. Results did not vary by race/ethnicity. CONCLUSIONS: The protective effect of increased body size in maintaining bone mass is likely due to the influence of lean tissue. These results suggest that maintenance of lean mass is the most promising strategy in maintaining bone health with advancing age.