RESUMO
Frontier orbitals determine fundamental molecular properties such as chemical reactivities. Although electron distributions of occupied orbitals can be imaged in momentum space by photoemission tomography, it has so far been impossible to follow the momentum-space dynamics of a molecular orbital in time, for example, through an excitation or a chemical reaction. Here, we combined time-resolved photoemission using high laser harmonics and a momentum microscope to establish a tomographic, femtosecond pump-probe experiment of unoccupied molecular orbitals. We measured the full momentum-space distribution of transiently excited electrons, connecting their excited-state dynamics to real-space excitation pathways. Because in molecules this distribution is closely linked to orbital shapes, our experiment may, in the future, offer the possibility of observing ultrafast electron motion in time and space.
RESUMO
BACKGROUND/OBJECTIVES: Primary adult-type lactose malabsorption (PALM) is a widespread inherited autosomal recessive condition, which is considered to be associated with osteoporosis. This prospective study aimed at assessing the 25-hydroxy-vitamin D (25(OH)D) status and serum CrossLaps levels in individuals with PALM and normal controls. SUBJECTS/METHODS: All participants (n=210) underwent genotyping for the LCT C/T-13910 polymorphism, 25(OH)D and CrossLaps measurements and clinical examinations. In addition, the anthropometric data (that is, height, weight and body mass index) were determined. RESULTS: Fifty-five individuals with PALM (that is, LCT C/C-13910 homozygotes) showed lower 25(OH)D (mean: 24.95±10.04 vs 28.59±9.56 ng/ml, P=0.018) and higher CrossLaps serum levels (mean: 0.46±0.31 vs 0.43±0.49 ng/ml, P=0.251) compared with 155 normal controls (that is, LCT C/T-13910 hetero- or T/T-13910 homozygotes). Anthropometric data were similar between PALM probands and controls. CONCLUSIONS: Individuals with PALM were found to have lower 25(OH)D and higher CrossLaps serum levels compared with normal controls. In order to preserve life-long bone health, routine 25(OH)D and CrossLaps serum measurements should be performed in individuals with PALM.
Assuntos
Colágeno Tipo I/sangue , Colágeno/sangue , Absorção Intestinal , Lactase/deficiência , Intolerância à Lactose/complicações , Lactose/metabolismo , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Deficiência de Vitamina D/complicações , Vitamina D/análogos & derivados , Adulto , Índice de Massa Corporal , Feminino , Genótipo , Humanos , Lactase/sangue , Lactase/genética , Lactase/metabolismo , Intolerância à Lactose/sangue , Intolerância à Lactose/genética , Masculino , Pessoa de Meia-Idade , Osteoporose/etiologia , Osteoporose/genética , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Vitamina D/sangue , Deficiência de Vitamina D/sangue , Vitaminas/sangue , Adulto JovemRESUMO
Transient Fanconi syndrome without azotemia was diagnosed in a dog and was associated with ingestion of Chinese chicken jerky treats. Fanconi syndrome is a proximal renal tubular defect and a diagnosis was made based upon severe glucosuria with normoglycemia, and severe generalized aminoaciduria. The clinical signs of polyuria and polydipsia as well as the massive urinary metabolic abnormalities resolved after jerky treat withdrawal. While frequently seen in North America and Australia, this is the first report of jerky treat induced Fanconi syndrome in continental Europe. Clinicians should be aware of this potential intoxication and be vigilant for a history of jerky treat consumption in a dog with glucosuria.
Assuntos
Doenças do Cão/etiologia , Síndrome de Fanconi/veterinária , Alimentos em Conserva/intoxicação , Produtos da Carne/intoxicação , Animais , Doenças do Cão/diagnóstico , Doenças do Cão/terapia , Cães , Síndrome de Fanconi/diagnóstico , Síndrome de Fanconi/etiologia , Síndrome de Fanconi/terapia , Feminino , Glicosúria/diagnóstico , Glicosúria/etiologia , Glicosúria/veterináriaRESUMO
The public health of our society is challenged by a continuous increase in life expectancy. Hence, biomedical aging research is enjoying a steadily increasing popularity but also enlightens our understanding of age-related diseases by a number of striking results from basic research. One of the most striking changes that occurs during normal human aging is an overall diminution of immune functions, a phenomenon often termed immunosenescence. Starting from some highly exciting examples from basic immunological research, this article sheds light on which impact normal human aging has on several immune defence mechanisms. In addition, clinical consequences in view of Alzheimer's disease, immunogenicity of vaccines and autoimmune diseases are discussed.
Assuntos
Envelhecimento/imunologia , Alergia e Imunologia/tendências , Pesquisa Biomédica/tendências , Medicina Baseada em Evidências/tendências , Doenças do Sistema Imunitário/imunologia , Imunidade Inata/imunologia , Modelos Imunológicos , Adulto , Idoso , Humanos , Pessoa de Meia-IdadeRESUMO
BACKGROUND: In collaboration with the Houston Department of Health and Human Services, the authors implemented and evaluated a urine-based chlamydia screening program in incarcerated youth in Harris County, Texas, and assessed predictor variables for infection. GOAL: To implement and evaluate chlamydia screening in incarcerated youth. STUDY DESIGN: The authors determined prevalence of chlamydial infection, treatment rates, and predictor variables in 589 youth and repeated the measures 6 months later in 975 additional youth. RESULTS: Initially, the prevalence of infection was 9.6% in males and 28.1% in females; 88% of infected youth were treated while incarcerated. White males had a significantly lower prevalence of chlamydial infection; however, consistent condom use was not associated with a lower prevalence of chlamydia. In the 6-month assessment of chlamydia prevalence in 975 youth, prevalence and treatment rates remained high and predictor variables were similar. CONCLUSION: The authors instituted a screening program for chlamydial infection in incarcerated youth that was performing well at reassessment 6 months later.