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1.
Acta Paediatr ; 113(4): 818-826, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37776041

RESUMO

AIM: To examine trends in all body mass index (BMI) groups in children from 1936 to 2011. METHODS: We included 197 694 girls and 201 276 boys from the Copenhagen School Health Records Register, born between 1930 and 1996, with longitudinal weight and height measurements (6-14 years). Using International Obesity Task Force criteria, BMI was classified as underweight, normal-weight, overweight and obesity. Sex- and age-specific prevalences were calculated. RESULTS: From the 1930s, the prevalence of underweight was stable until a small increase occurred from 1950 to 1970s, and thereafter it declined into the early 2000s. Using 7-year-olds as an example, underweight changed from 10% to 7% in girls and from 9% to 6% in boys during the study period. The prevalence of overweight plateaued from 1950 to 1970s and then steeply increased from 1970s onwards and in 1990-2000s 15% girls and 11% boys at 7 years had overweight. The prevalence of obesity particularly increased from 1980s onwards and in 1990-2000s 5% girls and 4% boys at 7 years had obesity. These trends slightly differed by age. CONCLUSION: Among Danish schoolchildren, the prevalence of underweight was greater than overweight until the 1980s and greater than obesity throughout the period. Thus, monitoring the prevalence of childhood underweight remains an important public health issue.


Assuntos
Sobrepeso , Magreza , Masculino , Criança , Feminino , Humanos , Índice de Massa Corporal , Magreza/epidemiologia , Sobrepeso/epidemiologia , Obesidade/epidemiologia , Prevalência , Dinamarca/epidemiologia
2.
Scand J Rheumatol ; 51(6): 461-469, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34514936

RESUMO

OBJECTIVES: Adult obesity may be positively associated with risks of rheumatoid arthritis (RA), but associations with early life body size are unknown. We examined whether birthweight, childhood body mass index (BMI), height, and changes in BMI and height were associated with risks of adult RA. METHOD: A cohort of 346 602 children (171 127 girls) from the Copenhagen School Health Records Register, born in 1930-1996, with measured weights and heights from 7 to 13 years of age, were included. Information on RA, including serological status, came from national registers from 1977 to 2017. Cox regressions were performed. RESULTS: During a median of 35.1 years of observation time per person, 4991 individuals (3565 women) were registered with RA. Among girls, per BMI z-score, risks of RA and seropositive RA increased by 4-9% and 6-10%, respectively. Girls with overweight had higher risks of RA than girls without overweight. Girls who became overweight by 13 years of age had increased risks of RA compared to girls without overweight at 7 or 13 years (hazard ratio = 1.40, 95% confidence interval 1.19-1.66). For boys, associations between BMI and RA (including seropositive RA) were not statistically significant. Height was not associated with RA (any type) in girls. Taller boys had higher risks of RA, especially seropositive RA. Birthweight was not associated with RA. CONCLUSIONS: Among women, childhood adiposity was associated with increased risks of RA. Among men, childhood height was positively associated with risks of RA. These findings support the hypothesis that early life factors may be important in the aetiology of RA.


Assuntos
Artrite Reumatoide , Sobrepeso , Adulto , Criança , Masculino , Feminino , Humanos , Idoso de 80 Anos ou mais , Adolescente , Estudos de Coortes , Fatores de Risco , Índice de Massa Corporal , Tamanho Corporal , Artrite Reumatoide/epidemiologia , Artrite Reumatoide/etiologia , Dinamarca/epidemiologia
3.
Adv Dent Res ; 30(2): 34-39, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31633390

RESUMO

Technological advancements have revolutionized our understanding of the complexity and importance of the human microbiome. This progress has also emphasized the need for precision therapeutics, as it has underscored the dilemmas, such as dysbiosis and increasing antibiotic resistance, associated with current, broad-spectrum treatment modalities. Dental caries remains the most common chronic disease worldwide, accompanied by a tremendous financial and social burden, despite widespread and efficacious fluoride and hygienic regimens. Over the past several decades, various precision approaches to combat dental caries, including vaccines, probiotics, and antimicrobial compounds, have been pursued. Despite the distinct overall conceptual strengths of each approach, for various reasons, there are currently no approved precision antibiotic therapeutics to prevent dental caries. Specifically targeted antimicrobial peptides (STAMPs) are synthetic molecules that combine the antibiotic moiety of a traditional antimicrobial peptide with a targeting domain to provide specificity against a particular organism. Conjoining the killing domain from the antimicrobial, novispirin G10, and a targeting domain derived from the Streptococcus mutans pheromone, CSP, the STAMP C16G2 was designed to provide targeted killing of S. mutans, widely considered the keystone species in dental caries pathogenesis. C16G2 was able to selectively eliminate S. mutans from complex ecosystems while leaving closely related, yet health-associated, oral species unharmed. This remodeling of the dental plaque community is expected to have significant advantages compared to conventional broad-spectrum mouthwashes, as the intact, surviving community is apt to prevent reinfection by pathogens. Following successful phase I clinical trials that evaluated the safety and basic microbiology of C16G2 treatments, the phase II trials of several C16G2 formulations are currently in progress. C16G2 represents an exciting advance in precision therapeutics, and the STAMP platform provides vast opportunities for both the development of additional therapeutics and the overall study of microbial ecology.


Assuntos
Cárie Dentária , Placa Dentária , Microbiota , Biofilmes , Humanos , Streptococcus mutans
4.
J Bacteriol ; 200(12)2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29632089

RESUMO

Streptococcus mutans, the organism most frequently associated with the development of dental caries, is able to utilize a diverse array of carbohydrates for energy metabolism. One such molecule is trehalose, a disaccharide common in human foods, which has been recently implicated in enhancing the virulence of epidemic strains of the pathogen Clostridium difficile In this study, mutants with deletions of all three genes in the putative S. mutans trehalose utilization operon were characterized, and the genes were shown to be required for wild-type levels of growth when trehalose was the only carbohydrate source provided. Interestingly, the TreR transcriptional regulator appeared to be critical for responding to oxidative stress and for mounting a protective stress tolerance response following growth at moderately acidic pH. mRNA sequencing (RNA-seq) of a treR deletion mutant suggested that in S. mutans, TreR acts as a trehalose-sensing activator of transcription of the tre operon, rather than as a repressor, as described in other species. In addition, deletion of treR caused the downregulation of a number of genes involved in genetic competence and bacteriocin production, supporting the results of a recent study linking trehalose and the S. mutans competence pathways. Finally, deletion of treR compromised the ability of S. mutans to inhibit the growth of the competing species Streptococcus gordonii and Lactococcus lactis Taking the results together, this study solidifies the role of the S. mutans tre operon in trehalose utilization and suggests novel functions for the TreR regulator, including roles in the stress response and competitive fitness.IMPORTANCES. mutans is the primary etiologic agent of dental caries, which globally is the most common chronic disease. S. mutans must be able to outcompete commensal organisms in its dental plaque niche in order to establish persistence and pathogenesis. To that end, S. mutans metabolizes a diverse array of carbohydrates to generate acid and impede its acid-sensitive neighbors. Additionally, S. mutans utilizes quorum signaling through genetic competence-associated pathways to induce production of toxins to kill its rivals. This study definitively shows that the S. mutans trehalose utilization operon is required for growth in trehalose. Furthermore, this study suggests that the S. mutans TreR transcriptional regulator has a novel role in virulence through regulation of genes involved in genetic competence and toxin production.


Assuntos
Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/biossíntese , Regulação Bacteriana da Expressão Gênica , Óperon , Proteínas Repressoras/metabolismo , Streptococcus mutans/metabolismo , Trealose/metabolismo , Proteínas de Bactérias/genética , Bacteriocinas/biossíntese , Biofilmes , Proteínas Repressoras/genética , Deleção de Sequência , Streptococcus mutans/genética , Streptococcus mutans/crescimento & desenvolvimento , Ativação Transcricional
5.
Int J Obes (Lond) ; 42(4): 594-602, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28883541

RESUMO

BACKGROUND AND OBJECTIVES: Prenatal risk factors for childhood overweight may operate indirectly through development in body size in early life and/or directly independent hereof. We quantified the effects of maternal and paternal body mass index (BMI), maternal age, socioeconomic position (SEP), parity, gestational weight gain, maternal smoking during pregnancy, caesarean section, birth weight, and BMI at 5 and 12 months on BMI and overweight at 7 and 11 years. METHODS: Family triads with information on maternal, paternal and child BMI at ages 7 (n=29 374) and 11 years (n=18 044) were selected from the Danish National Birth Cohort. Information originated from maternal interviews and medical health examinations. Path analysis was used to estimate the direct and indirect effects of prenatal risk factors on childhood BMI z-scores (BMIz per unit score of the risk factor). Logistic regression was used to examine associations with overweight. RESULTS: The strongest direct effects on BMIz at age 7 were found for maternal and paternal BMI (0.19 BMIz and 0.14 BMIz per parental BMIz), low SEP (0.08 BMIz), maternal smoking (0.12 BMIz) and higher BMIz at 5 and 12 months (up to 0.19 BMIz per infant BMIz). For BMIz at age 11 with BMIz at age 7 included in the model, similar effects were found, but the direct effects of BMIz at age 5 and 12 months were mediated through BMI at age 7 (0.62 BMIz per BMIz). Same results were found for overweight. The sum of the direct effects can be translated to approximate absolute measures: 2.4 kg at 7 years, 5.7 kg at 11 years, in a child with average height and BMI. CONCLUSIONS: Parental BMI, low SEP and smoking during pregnancy have persisting, strong and direct effects on child BMI and overweight independent of birth weight and infancy BMI.


Assuntos
Índice de Massa Corporal , Obesidade Infantil/epidemiologia , Adulto , Peso ao Nascer , Tamanho Corporal , Criança , Estudos de Coortes , Dinamarca/epidemiologia , Escolaridade , Feminino , Humanos , Masculino , Fatores de Risco , Fumar
6.
Pharmacogenomics J ; 17(2): 112-120, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27779243

RESUMO

As the common birthplace of all human populations, modern humans have lived longer on the African continent than in any other geographical region of the world. This long history, along with the evolutionary need to adapt to environmental challenges such as exposure to infectious agents, has led to greater genetic variation in Africans. The vast genetic variation in Africans also extends to genes involved in the absorption, distribution, metabolism and excretion of pharmaceuticals. Ongoing cataloging of these clinically relevant variants reveals huge allele-frequency differences within and between African populations. Here, we examine Africa's large burden of infectious disease, discuss key examples of known genetic variation modulating disease risk, and provide examples of clinically relevant variants critical for establishing dosing guidelines. We propose that a more systematic characterization of the genetic diversity of African ancestry populations is required if the current benefits of precision medicine are to be extended to these populations.


Assuntos
Anti-Infecciosos/uso terapêutico , População Negra/genética , Doenças Transmissíveis/tratamento farmacológico , Doenças Transmissíveis/genética , Evolução Molecular , Farmacogenética , Variantes Farmacogenômicos , África/epidemiologia , Anti-Infecciosos/efeitos adversos , Anti-Infecciosos/farmacocinética , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/transmissão , Frequência do Gene , Variação Genética , Genótipo , Humanos , Fenótipo , Resultado do Tratamento
7.
Int J Obes (Lond) ; 40(7): 1096-102, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27121254

RESUMO

BACKGROUND: Endometrial cancer risk factors include adult obesity and taller stature, but the influence of size earlier in life is incompletely understood. We examined whether childhood body mass index (BMI; kg m(-2)) and height were associated with histologic subtypes of endometrial cancer. METHODS: From the Copenhagen School Health Records Register, 155 505 girls born 1930-1989 with measured weights and heights from 7 to 13 years were linked to health registers. BMI and height were transformed to age-specific z-scores. Hazard ratios (HRs) and 95% confidence intervals were estimated by Cox regressions. RESULTS: A total of 1020 endometrial cancers were recorded. BMI was non-linearly associated with all endometrial cancers, oestrogen-dependent cancers and the subtype of endometrioid adenocarcinomas; associations were statistically significant and positive above a z-score=0 and non-significant below zero. Compared with a 7-year-old girl with a BMI z-score=0, an equally tall girl who was 3.6 kg heavier (BMI z-score=1.5) had a hazard ratio=1.53 (95% confidence interval: 1.29-1.82) for endometrioid adenocarcinoma. BMI was not associated with non-oestrogen-dependent cancers, except at the oldest childhood ages. Height at all ages was statistically significant and positively associated with all endometrial cancers, except non-oestrogen-dependent cancers. At 7 years, per ~5.2 cm (1 z-score), the risk of endometrioid adenocarcinoma was 1.18 (95% confidence interval: 1.09-1.28). Among non-users of unopposed oestrogens, associations between BMI and endometrioid adenocarcinoma strengthened, but no effects on height associations were observed. CONCLUSIONS: Endometrial carcinogenesis is linked to early-life body size, suggesting that childhood BMI and height may be useful indicators for the risk of later development of endometrial cancer and might aid in the early prevention of obesity-related endometrial cancers.


Assuntos
Estatura , Índice de Massa Corporal , Neoplasias do Endométrio/classificação , Neoplasias do Endométrio/complicações , Estrogênios/metabolismo , Obesidade Infantil/complicações , Adolescente , Peso Corporal , Criança , Dinamarca/epidemiologia , Neoplasias do Endométrio/epidemiologia , Neoplasias do Endométrio/metabolismo , Feminino , Humanos , Masculino , Obesidade Infantil/epidemiologia , Obesidade Infantil/metabolismo , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Aumento de Peso
8.
Int J Obes (Lond) ; 40(9): 1376-83, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27168050

RESUMO

BACKGROUND: Heavy children have an increased risk of being overweight young adults. Whether this risk remains in late adulthood is not well-understood. We investigated body mass index (BMI; kg m(-2)) tracking from childhood to late adulthood. METHODS: From the Copenhagen School Health Records Register, 72 959 men and 25 252 women born between 1930 and 1989 with BMI values at 7 and/or 13 years and as adults were included. Using a meta-regression approach, age- and sex-specific partial correlation analyses and logistic regressions were performed. RESULTS: Correlations between BMI at 7 years and young adult ages (18-19 years) were r=0.55 for men and r=0.55 for women. At late ages (60-69 years) these were r=0.28 for men and r=0.26 for women. The correlations did not differ by birth years. Compared with normal-weight 7-year-olds, overweight children had a higher odds of overweight at 18-19 years; odds ratio (OR)=14.02 (95% confidence interval (CI): 12.14-16.19) for men and 10.46 (95% CI: 4.82-22.70) for women. At ages 60-69 years ORs were 5.46 (95% CI: 0.95-31.36) for men and 1.61 (95% CI: 0.83-3.15) for women. Correlations and ORs were stronger at age 13 years than age 7 years as expected, but the overall patterns were similar. CONCLUSIONS: BMI tracking was weaker at late adult ages than at young adult ages. Although BMI tracks across the life course, childhood BMI is relatively poor at identifying later adult overweight or obesity at ages when chronic diseases generally emerge.


Assuntos
Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Doenças Metabólicas/epidemiologia , Sistema de Registros , Adolescente , Adulto , Fatores Etários , Idoso , Peso Corporal/fisiologia , Criança , Estudos Transversais , Dinamarca/epidemiologia , Feminino , Seguimentos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fatores de Risco , Fatores Sexuais , Adulto Jovem
9.
J Bacteriol ; 197(23): 3645-57, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26350138

RESUMO

UNLABELLED: Previous studies of the oral pathogen Streptococcus mutans have determined that this Gram-positive facultative anaerobe mounts robust responses to both acid and oxidative stresses. The water-forming NADH oxidase (Nox; encoded by nox) is thought to be critical for the regeneration of NAD(+), for use in glycolysis, and for the reduction of oxygen, thereby preventing the formation of damaging reactive oxygen species. In this study, the free NAD(+)/NADH ratio in a nox deletion strain (Δnox) was discovered to be remarkably higher than that in the parent strain, UA159, when the strains were grown in continuous culture. This unanticipated result was explained by significantly elevated lactate dehydrogenase (Ldh; encoded by ldh) activity and ldh transcription in the Δnox strain, which was mediated in part by the redox-sensing regulator Rex. cDNA microarray analysis of S. mutans cultures exposed to simultaneous acid stress (growth at a low pH) and oxidative stress (generated through the deletion of nox or the addition of exogenous oxygen) revealed a stress response synergistically heightened over that with either stress alone. In the Δnox strain, this elevated stress response included increased glucose phosphoenolpyruvate phosphotransferase system (PTS) activity, which appeared to be due to elevated manL transcription, mediated in part, like elevated ldh transcription, by Rex. While the Δnox strain does possess a membrane composition different from that of the parent strain, it did not appear to have defects in either membrane permeability or ATPase activity. However, the altered transcriptome and metabolome of the Δnox strain were sufficient to impair its ability to compete with commensal peroxigenic oral streptococci during growth under aerobic conditions. IMPORTANCE: Streptococcus mutans is an oral pathogen whose ability to outcompete commensal oral streptococci is strongly linked to the formation of dental caries. Previous work has demonstrated that the S. mutans water-forming NADH oxidase is critical for both carbon metabolism and the prevention of oxidative stress. The results of this study show that upregulation of lactate dehydrogenase, mediated through the redox sensor Rex, overcompensates for the loss of nox. Additionally, nox deletion led to the upregulation of mannose and glucose transport, also mediated through Rex. Importantly, the loss of nox rendered S. mutans defective in its ability to compete directly with two species of commensal streptococci, suggesting a role for nox in the pathogenic potential of this organism.


Assuntos
Proteínas de Bactérias/metabolismo , L-Lactato Desidrogenase/metabolismo , Complexos Multienzimáticos/metabolismo , NADH NADPH Oxirredutases/metabolismo , NAD/metabolismo , Streptococcus mutans/enzimologia , Proteínas de Bactérias/genética , L-Lactato Desidrogenase/genética , Complexos Multienzimáticos/genética , NADH NADPH Oxirredutases/genética , Estresse Oxidativo , Streptococcus mutans/genética , Streptococcus mutans/metabolismo
10.
Br J Cancer ; 112(3): 601-7, 2015 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-25562436

RESUMO

BACKGROUND: Middle-aged obese adults are at substantially elevated risk of oesophageal adenocarcinoma. It is unclear whether this risk originates earlier in life. METHODS: We assessed associations between childhood body mass index (BMI) and height-measured annually between ages 7 and 13-with adult oesophageal adenocarcinoma in a cohort from the Copenhagen School Health Records Register. Analyses included 255 053 children born during 1930-1971. Danish Cancer Registry linkage provided outcomes. We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) using Cox proportional hazards regression. RESULTS: During 5.4 million person-years of follow-up, 254 (216 males) incident oesophageal adenocarcinomas occurred. At each examined age, cancer risk increased linearly per unit BMI z-score, although associations were only statistically significant for ages 9-13. The HR for the age of 13 years was 1.31 (95% CI: 1.13, 1.51) per unit BMI z-score. Associations were similar in men and women and across birth cohorts. Childhood height was not related to cancer risk in men but was in women, although these analyses included just 38 female cases. HRs per unit height z-score at the age of 13 years were 1.04 (0.90, 1.19) in males and 1.77 (1.27, 2.47) in females, with similar results observed at the other examined ages. CONCLUSION: Individuals with higher childhood BMI were at elevated risk of oesophageal adenocarcinoma, even though these cancers occurred many decades later in life. Although the mechanisms require further investigation, our findings provide additional evidence for the long-term health risks of childhood obesity.


Assuntos
Adenocarcinoma/epidemiologia , Índice de Massa Corporal , Desenvolvimento Infantil/fisiologia , Neoplasias Esofágicas/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
11.
J Bacteriol ; 196(12): 2166-77, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24682329

RESUMO

NADH oxidase (Nox, encoded by nox) is a flavin-containing enzyme used by the oral pathogen Streptococcus mutans to reduce diatomic oxygen to water while oxidizing NADH to NAD(+). The critical nature of Nox is 2-fold: it serves to regenerate NAD(+), a carbon cycle metabolite, and to reduce intracellular oxygen, preventing formation of destructive reactive oxygen species (ROS). As oxygen and NAD(+) have been shown to modulate the activity of the global transcription factors Spx and Rex, respectively, Nox is potentially poised at a critical junction of two stress regulons. In this study, microarray data showed that either addition of oxygen or loss of nox resulted in altered expression of genes involved in energy metabolism and transport and the upregulation of genes encoding ROS-metabolizing enzymes. Loss of nox also resulted in upregulation of several genes encoding transcription factors and signaling molecules, including the redox-sensing regulator gene rex. Characterization of the nox promoter revealed that nox was regulated by oxygen, through SpxA, and by Rex. These data suggest a regulatory loop in which the roles of nox in reduction of oxygen and regeneration of NAD(+) affect the activity levels of Spx and Rex, respectively, and their regulons, which control several genes, including nox, crucial to growth of S. mutans under conditions of oxidative stress.


Assuntos
Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Complexos Multienzimáticos/metabolismo , NADH NADPH Oxirredutases/metabolismo , NAD/metabolismo , Oxigênio/farmacologia , Streptococcus mutans/enzimologia , Deleção de Genes , Regulação Bacteriana da Expressão Gênica/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Complexos Multienzimáticos/genética , NADH NADPH Oxirredutases/genética , Regiões Promotoras Genéticas , Streptococcus mutans/genética , Streptococcus mutans/metabolismo
12.
Br J Cancer ; 111(1): 207-12, 2014 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-24867696

RESUMO

BACKGROUND: Prostate cancer aetiology is poorly understood. It may have origins early in life; previously we found a positive association with childhood height. The effects of early life body mass index (BMI; kg m(-2)) on prostate cancer remain equivocal. We investigated if childhood BMI, independently and adjusted for height, is positively associated with adult prostate cancer. METHODS: Subjects were a cohort of 125208 boys formed from the Copenhagen School Health Records Register, born 1930-1969 with height and weight measurements at 7-13 years. Cases were identified through linkage to the Danish Cancer Registry. Cox proportional hazards regressions were performed. RESULTS: Overall, 3355 men were diagnosed with prostate cancer. Body mass index during childhood was positively associated with adult prostate cancer. The hazard ratio of prostate cancer was 1.06 (95% confidence interval (CI): 1.01-1.10) per BMI z-score at age 7, and 1.05 (95% CI: 1.01-1.10) per BMI z-score at age 13. Estimates were similar and significant at all other ages. However, adjustment for childhood height attenuated the associations at all but the youngest ages as most estimates became nonsignificant. CONCLUSIONS: These results suggest that at most childhood ages, BMI does not confer an additional risk for prostate cancer beyond that of height.


Assuntos
Índice de Massa Corporal , Neoplasias da Próstata/epidemiologia , Adolescente , Adulto , Criança , Estudos de Coortes , Dinamarca/epidemiologia , Humanos , Incidência , Masculino , Obesidade/epidemiologia , Fatores de Risco , Adulto Jovem
13.
Int J Obes (Lond) ; 38(10): 1305-11, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24942870

RESUMO

BACKGROUND: Weight and weight gain throughout infancy are related to later obesity, but whether the strength of the associations varies during the infancy period is uncertain. AIMS: Our aims were to identify the period of infancy when change in body weight has the strongest association with adult body mass index (BMI) and also the extent to which these associations during infancy are mediated through childhood BMI. METHODS: The Copenhagen Perinatal Cohort, in which participants were followed from birth through 42 years of age, provided information on weight at 12 months and BMI at 42 years for 1633 individuals. Information on weight at birth, 2 weeks, 1, 2, 3, 4 and 6 months was retrieved from health visitors' records and information on BMI at ages 7 and 13 years from school health records. The associations of infant weight and weight gain standard deviation scores (SDS) with adult BMI-SDS were analyzed using multiple linear regression and path analysis. RESULTS: Higher-weight-SDS at all ages from birth to an age 12 months were associated with higher-BMI-SDS at 42 years (regression coefficients 0.08-0.12). Infant weight gain-SDS was associated with greater BMI-SDS at 42 years only between birth and 3 months (0.09, 95% confidence intervals (CI) 0.04, 0.15) driven by an association between 2 and 3 months (0.12, 95% CI: 0.04, 0.20). The latter was partly mediated through later BMI in the path analysis. Infant weight gain-SDS between 3 and 12 months was not associated with greater BMI-SDS at 42 years. CONCLUSIONS: Faster weight gain during only the first 3 months of infancy was associated with increased adult BMI, although not in a consistent monthly pattern. Adult BMI is more sensitive to high weight gain during early infancy than late infancy, but not specifically to the first month of life.


Assuntos
Aleitamento Materno/estatística & dados numéricos , Fenômenos Fisiológicos da Nutrição do Lactente , Obesidade/epidemiologia , Aumento de Peso , Adolescente , Adulto , Idade de Início , Composição Corporal , Índice de Massa Corporal , Criança , Estudos de Coortes , Dinamarca/epidemiologia , Feminino , Humanos , Lactente , Masculino , Obesidade/etiologia , Obesidade/prevenção & controle , Valor Preditivo dos Testes , Fatores de Risco , Fatores de Tempo , Circunferência da Cintura
14.
J Neural Eng ; 21(3)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38862007

RESUMO

Objective.Electrodes chronically implanted in the brain undergo complex changes over time that can lower the signal to noise ratio (SNR) of recorded signals and reduce the amount of energy delivered to the tissue during therapeutic stimulation, both of which are relevant for the development of robust, closed-loop control systems. Several factors have been identified that link changes in the electrode-tissue interface (ETI) to increased impedance and degraded performance in micro- and macro-electrodes. Previous studies have demonstrated that brief pulses applied every few days can restore SNR to near baseline levels during microelectrode recordings in rodents, a process referred to as electrical rejuvenation. However, electrical rejuvenation has not been tested in clinically relevant macroelectrode designs in large animal models, which could serve as preliminary data for translation of this technique. Here, several variations of this approach were tested to characterize parameters for optimization.Approach. Alternating-current (AC) and direct-current (DC) electrical rejuvenation methods were explored in three electrode types, chronically implanted in two adult male nonhuman primates (NHP) (Macaca mulatta), which included epidural electrocorticography (ECoG) electrodes and penetrating deep-brain stimulation (DBS) electrodes. Electrochemical impedance spectroscopy (EIS) was performed before and after each rejuvenation paradigm as a gold standard measure of impedance, as well as at subsequent intervals to longitudinally track the evolution of the ETI. Stochastic error modeling was performed to assess the standard deviation of the impedance data, and consistency with the Kramers-Kronig relations was assessed to evaluate the stationarity of EIS measurement.Main results. AC and DC rejuvenation were found to quickly reduce impedance and minimize the tissue component of the ETI on all three electrode types, with DC and low-frequency AC producing the largest impedance drops and reduction of the tissue component in Nyquist plots. The effects of a single rejuvenation session were found to last from several days to over 1 week, and all rejuvenation pulses induced no observable changes to the animals' behavior.Significance. These results demonstrate the effectiveness of electrical rejuvenation for diminishing the impact of chronic ETI changes in NHP with clinically relevant macroelectrode designs.


Assuntos
Eletrodos Implantados , Macaca mulatta , Animais , Masculino , Impedância Elétrica , Microeletrodos , Estimulação Elétrica/métodos , Estimulação Elétrica/instrumentação , Razão Sinal-Ruído
15.
NPJ Biofilms Microbiomes ; 10(1): 37, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565843

RESUMO

Prolonged exposure to antibiotics at low concentration can promote processes associated with bacterial biofilm formation, virulence and antibiotic resistance. This can be of high relevance in microbial communities like the oral microbiome, where commensals and pathogens share a common habitat and where the total abundance of antibiotic resistance genes surpasses the abundance in the gut. Here, we used an ex vivo model of human oral biofilms to investigate the impact of ampicillin on biofilm viability. The ecological impact on the microbiome and resistome was investigated using shotgun metagenomics. The results showed that low concentrations promoted significant shifts in microbial taxonomic profile and could enhance biofilm viability by up to 1 to 2-log. For the resistome, low concentrations had no significant impact on antibiotic resistance gene (ARG) diversity, while ARG abundance decreased by up to 84%. A positive correlation was observed between reduced microbial diversity and reduced ARG abundance. The WHO priority pathogens Streptococcus pneumoniae and Staphylococcus aureus were identified in some of the samples, but their abundance was not significantly altered by ampicillin. Most of the antibiotic resistance genes that increased in abundance in the ampicillin group were associated with streptococci, including Streptococcus mitis, a well-known potential donor of ARGs to S. pneumoniae. Overall, the results highlight the potential of using the model to further our understanding of ecological and evolutionary forces driving antimicrobial resistance in oral microbiomes.


Assuntos
Antibacterianos , Microbiota , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Ampicilina/farmacologia , Bactérias/genética , Biofilmes
16.
Br J Cancer ; 107(1): 165-8, 2012 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-22677900

RESUMO

BACKGROUND: Tallness has consistently been associated with an increased risk of breast cancer. We investigated the association further by decomposing height into leg length and sitting height. METHODS: From the prospective Danish cohort 'Diet, Cancer and Health', 23 864 postmenopausal women enrolled during 1993-1997 were followed for a diagnosis of breast cancer in the Danish Cancer Registry through 2009. RESULTS: The incidence rate ratios for breast cancer were 1.11 (95% CI=1.06-1.16) for each 5 cm increase in total height and 1.09 (95% CI=1.01-1.17) and 1.14 (95% CI=1.04-1.25) for each 5 cm increase in leg length and sitting height, respectively. There was no statistical significant difference between the associations for leg length and sitting height (P=0.47). CONCLUSION: Leg length does not seem to be more strongly associated with breast cancer among postmenopausal women than sitting height.


Assuntos
Estatura , Neoplasias da Mama/epidemiologia , Perna (Membro)/anatomia & histologia , Dinamarca/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Risco
17.
Int J Obes (Lond) ; 36(10): 1306-11, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22907690

RESUMO

BACKGROUND: Infant weight and weight gain are positively associated with later obesity, but whether there is a particular critical time during infancy remains uncertain. OBJECTIVE: The aim was to investigate when and how weight and weight gain during infancy become associated with childhood obesity. METHODS: In a cohort representing 28 340 children born from 1959-67 and measured in Copenhagen schools, 962 obese children (2007 World Health Organization criteria), were compared with a 5% randomly selected sub-cohort of 1417 children. Information on weight at birth, 2 weeks, 1, 2, 3, 4, 6 and 9 months was retrieved from health visitors' records. Odds ratios and 95% confidence intervals (CI) for childhood obesity by tertiles of weight at each age and by change in tertiles of weight between two consecutive measurements were estimated using multivariate logistic regression with adjustment for indicators of socioeconomic status, preterm birth, and breastfeeding. RESULTS: Compared with children in the middle weight-tertile, children with a weight in the upper tertile had a 1.36-fold (CI, 1.10-1.69) to 1.72-fold (CI, 1.36-2.18) higher risk of childhood obesity from birth through 9 months, whereas children in the lower weight-tertile had almost half the risk of obesity from 2 through 9 months. The risk of childhood obesity associated with change in weight-tertile in each interval was stable at ∼1.5-fold per weight-tertile increase throughout infancy. CONCLUSIONS: Infant weight and weight gain are associated with obesity in childhood already during the first months of life. Determinants of weight gain shortly after birth may be a suitable target for prevention of obesity.


Assuntos
Peso Corporal , Aleitamento Materno/estatística & dados numéricos , Fórmulas Infantis/estatística & dados numéricos , Fenômenos Fisiológicos da Nutrição do Lactente , Obesidade/epidemiologia , Aumento de Peso , Adulto , Idade de Início , Estudos de Casos e Controles , Estudos de Coortes , Dinamarca/epidemiologia , Epigenômica , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Obesidade/prevenção & controle , Razão de Chances , Valor Preditivo dos Testes , Gravidez , População Branca
18.
Sci Rep ; 11(1): 23054, 2021 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-34845232

RESUMO

Central thalamic deep brain stimulation (CT-DBS) is an investigational therapy to treat enduring cognitive dysfunctions in structurally brain injured (SBI) patients. However, the mechanisms of CT-DBS that promote restoration of cognitive functions are unknown, and the heterogeneous etiology and recovery profiles of SBI patients contribute to variable outcomes when using conventional DBS strategies,which may result in off-target effects due to activation of multiple pathways. To disambiguate the effects of stimulation of two adjacent thalamic pathways, we modeled and experimentally compared conventional and novel 'field-shaping' methods of CT-DBS within the central thalamus of healthy non-human primates (NHP) as they performed visuomotor tasks. We show that selective activation of the medial dorsal thalamic tegmental tract (DTTm), but not of the adjacent centromedian-parafascicularis (CM-Pf) pathway, results in robust behavioral facilitation. Our predictive modeling approach in healthy NHPs directly informs ongoing and future clinical investigations of conventional and novel methods of CT-DBS for treating cognitive dysfunctions in SBI patients, for whom no therapy currently exists.


Assuntos
Comportamento Animal , Mapeamento Encefálico , Estimulação Encefálica Profunda/métodos , Eletrodos Implantados , Imageamento por Ressonância Magnética/métodos , Tálamo/diagnóstico por imagem , Tálamo/fisiologia , Animais , Biofísica , Cognição/fisiologia , Análise de Elementos Finitos , Macaca mulatta , Masculino , Análise Multivariada , Vias Neurais , Análise de Regressão , Visão Ocular
19.
J Dent Res ; 99(8): 969-976, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32298190

RESUMO

Early childhood caries (ECC) is a chronic disease affecting the oral health of children globally. This disease is multifactorial, but a primary factor is cariogenic microorganisms such as Streptococcus mutans. Biosynthetic gene clusters (BGCs) encode small molecules with diverse biological activities that influence the development of many microbial diseases, including caries. The purpose of this study was to identify BGCs in S. mutans from a high-caries risk study population using whole-genome sequencing and assess their association with ECC. Forty representative S. mutans isolates were selected for genome sequencing from a large-scale epidemiological study of oral microbiology and dental caries in children from a localized Alabama population. A total of 252 BGCs were identified using the antiSMASH BGC-mining tool. Three types of BGCs identified herein-butyrolactone-like, ladderane-like, and butyrolactone-ladderane-like hybrid (BL-BGC)-have not been reported in S. mutans. These 3 BGCs were cross-referenced against public transcriptomics data, and were found to be highly expressed in caries subjects. Furthermore, based on a polymerase chain reaction screening for core BL genes, 93% of children with BL-BGC had ECC. The role of BL-BGC was further investigated by examining cariogenic traits and strain fitness in a deletion mutant using in vitro biofilm models. Deletion of the BL-BGC significantly increased biofilm pH as compared to the parent strain, while other virulence and fitness properties remained unchanged. Intriguingly, BL-BGC containing strains produced more acid, a key cariogenic feature, and less biofilm than the model cariogenic strain S. mutans UA159, suggesting the importance of this BL-BGC in S. mutans-mediated cariogenesity. The structure of any BL-BGC derived metabolites, their functions, and mechanistic connection with acid production remain to be elucidated. Nevertheless, this study is the first to report the clinical significance of a BL-BGC in S. mutans. This study also highlights pangenomic diversity, which is likely to affect phenotype and virulence.


Assuntos
Cárie Dentária , Streptococcus mutans , Biofilmes , Humanos , Família Multigênica , Streptococcus mutans/genética , Virulência/genética
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