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1.
J Nutr Health Aging ; 21(10): 1190-1199, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29188879

RESUMO

OBJECTIVE: To examine differences in diet and food purchasing behaviors between Black and White older women living in urban neighborhoods. DESIGN: Cross-sectional observational study. SETTING: Urban neighborhoods in Washington, DC, USA. PARTICIPANTS: Community-dwelling White and Black women of age 65 and older. MEASUREMENTS: Participants were queried on diet via 24-hour recalls, food purchasing habits, their use of neighborhood resources and local travel patterns. Frequency and location of self-reported food purchasing and consumption were compared by race. RESULTS: In 2014 and 2015, 49 White and 44 Black older women were enrolled in the study. Compared to Whites, Blacks reported lower daily caloric intake (mean (SD) 1314 (404) vs. 1529 (448), p=0.02), with a higher percent of calories from protein and fat 1.8 (7.0), p=0.03), and a slightly higher polyunsaturated to saturated fat ratio (p=0.05). Blacks had substantially lower alternate healthy eating index (AHEI) (33.5 (10.2) vs. 43.9 (10.8) of 80 possible points, p<0.001), daily intake (grams) of total fiber (15.3 (8.1) vs. 22.9 (8.5), p<0.001), insoluble fiber (10.8 (6.9) vs. 15.9 (6.5), p<0.001), and soluble fiber (4.5 (2.0) vs. 6.9 (2.8), p<0.001). Blacks had lower intake of micronutrients, alcohol and caffeine. Blacks shopped for groceries less often (4.4 (3.0) vs. 6.2 (3.0) monthly; p=0.006) and spent a longer time traveling to stores (15.8 (9.1) vs. 11.5 (7.2) minutes per trip, p=0.02). A lower percent of Blacks walked to stores (14% vs. 40%, p=0.003) and a higher percent of Blacks rode in a car with someone else (33% vs. 6%, p<0.001). CONCLUSIONS: In an urban setting, food consumption and purchasing behaviors differed substantially between older Black and White women, which should be further investigated and considered to promote healthy eating in older populations.


Assuntos
Dieta/métodos , Comportamento Alimentar/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Grupos Raciais , População Urbana
2.
Vet Pathol ; 38(4): 396-406, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11467473

RESUMO

The pathogenesis of vesicular stomatitis virus (VSV) infection has not been investigated previously in native New World rodents that may have a role in the epidemiology of the disease. In the present study, 45 juvenile and 80 adult deer mice (Peromyscus maniculatus) were inoculated intranasally with VSV New Jersey serotype (VSV-NJ) and examined sequentially over a 7-day period. Virus was detected by means of immunohistochemistry and in situ hybridization in all tissues containing histologic lesions. Viral antigen and mRNA were observed initially in olfactory epithelium neurons, followed by olfactory bulbs and more caudal olfactory pathways in the brain. Virus also was detected throughout the ventricular system in the brain and central canal of the spinal cord. These results support both viral retrograde transneuronal transport and viral spread within the ventricular system. Other tissues containing viral antigen included airway epithelium and macrophages in the lungs, cardiac myocytes, and macrophages in cervical lymph nodes. In a second experiment, 15 adult, 20 juvenile, and 16 nestling deer mice were inoculated intradermally with VSV-NJ. Adults were refractory to infection by this route; however, nestlings and juveniles developed disseminated central nervous system infections. Viral antigen also was detected in cardiac myocytes and lymph node macrophages in these animals. Viremia was detected by virus isolation in 35/72 (49%) intranasally inoculated juvenile and adult mice and in 17/36 (47%) intradermally inoculated nestlings and juveniles from day 1 to day 3 postinoculation. The documentation of viremia in these animals suggests that they may have a role in the epidemiology of vector-borne vesicular stomatitis.


Assuntos
Peromyscus , Infecções por Rhabdoviridae/veterinária , Doenças dos Roedores/virologia , Vesiculovirus/patogenicidade , Animais , Antígenos Virais/análise , Encéfalo/patologia , Encéfalo/virologia , Chlorocebus aethiops , DNA Viral/química , Feminino , Georgia/epidemiologia , Imuno-Histoquímica/veterinária , Hibridização In Situ/veterinária , Pulmão/patologia , Pulmão/virologia , Linfonodos/patologia , Linfonodos/virologia , Masculino , Camundongos , Mucosa Nasal/patologia , Mucosa Nasal/virologia , RNA Viral/química , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Infecções por Rhabdoviridae/epidemiologia , Infecções por Rhabdoviridae/virologia , Doenças dos Roedores/epidemiologia , Doenças dos Roedores/patologia , Células Vero , Vesiculovirus/genética , Vesiculovirus/isolamento & purificação , Viremia/veterinária , Viremia/virologia
3.
Cleft Palate Craniofac J ; 38(1): 30-7, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11204679

RESUMO

OBJECTIVE: To summarize speech outcomes in children born with unilateral cleft lip and palate (UCLP) throughout the United Kingdom. DESIGN: Prospective descriptive study on a cross-sectional sample of children. PATIENTS/PARTICIPANTS: Data were collected for 238 5-year-olds (born between April 1, 1989, and March 31, 1991) and 218 12-year-olds (born between April 1, 1982, and March 31, 1984) with complete UCLP. MAIN OUTCOMES: Ratings of intelligibility, nasality, "speech cleft type characteristics" and speech therapy intervention. CONCLUSIONS: Nineteen percent of 5-year-olds and 4% of 12-year-olds were judged to be impossible to understand or just intelligible to strangers. Thirty-four percent of 5-year-olds and 17% of 12-year-olds had at least one serious error of consonant production. Eighteen percent of 5-year-olds and 12-year-olds had consistent hypernasality of mild, moderate, or severe degree. Approximately two-thirds of both age groups had undergone speech therapy.


Assuntos
Fenda Labial/terapia , Fissura Palatina/terapia , Fala/fisiologia , Criança , Pré-Escolar , Fenda Labial/fisiopatologia , Fissura Palatina/fisiopatologia , Estudos de Coortes , Estudos Transversais , Humanos , Variações Dependentes do Observador , Avaliação de Resultados em Cuidados de Saúde , Fonética , Estudos Prospectivos , Reprodutibilidade dos Testes , Distúrbios da Fala/classificação , Distúrbios da Fala/terapia , Inteligibilidade da Fala/fisiologia , Fonoterapia , Estatísticas não Paramétricas , Resultado do Tratamento , Reino Unido , Insuficiência Velofaríngea/classificação , Insuficiência Velofaríngea/cirurgia , Gravação de Videoteipe
4.
J Mass Spectrom ; 34(12): 1368-72, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10587634

RESUMO

A matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometer was developed which uses a novel reflectron composed of a grounded cylinder and an adjustable endcap electrode to provide high-order kinetic energy focusing for a miniaturized mass analyzer. The nearly quadratic potential form of the reflecting field focuses ions desorbed from a source of very small dimensions formed by placing the sample probe within the centered hole of the coaxial dual channel plate detector. At the same time, the depth of the reflectron can be adjusted to accommodate a short drift length between the source/detector and the reflectron. For larger drift lengths, in particular to allow the addition of an XY stage for the analysis of sample arrays, endcap reflectron focusing can be combined with time-delayed ion extraction to achieve good mass resolution. The instrument has been used for the analysis of peptides digested with trypsin or carboxypeptidase, and also small DNA oligomers.


Assuntos
Oligonucleotídeos/análise , Peptídeos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/instrumentação , Sequência de Aminoácidos , Sequência de Bases , Oligonucleotídeos/química , Peptídeos/química
5.
J Cell Sci ; 112 ( Pt 8): 1213-23, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10085256

RESUMO

Agrin, an extracellular matrix protein involved in neuromuscular junction formation, directs clustering of postsynaptic molecules, including acetylcholine receptors (AChRs). This activity resides entirely in the C-terminal portion of the protein, which consists of three laminin-like globular domains (G-domains: G1, G2 and G3) and four EGF-like repeats. Additionally, alternate mRNA splicing yields G-domain variants G2(0,4) with 0- or 4-amino-acid inserts, and G3(0, 8,11,19) with 0-, 8-, 11- or 19-amino-acid inserts. In order to better understand the contributions of individual domains and alternate splicing to agrin activity, single G-domains and covalently linked pairs of G-domains were expressed as soluble proteins and their AChR clustering activity measured on cultured C2 myotubes. These analyses reveal the following: (1) While only G3(8) exhibits detectable activity by itself, all G-domains studied (G1, G2(0), G2(4), G3(0) and G3(8)) enhance G3(8) activity when physically linked to G3(8). This effect is most pronounced when G2(4) is linked to G3(8) and is independent of the order of the G-domains. (2) The deletion of EGF-like repeats enhances activity. (3) Increasing the physical separation between linked G1 and G3(8) domains produces a significant increase in activity; similar alterations to linked G2 and G3(8) domains are without effect. (4) Clusters induced by two concatenated G3(8) domains are significantly smaller than all other agrin forms studied. These data suggest that agrin G-domains are the functional units which interact independently of their specific organization to yield AChR clustering. G-domain synergism resulting in biological output could be due to physical interactions between G-domains or, alternatively, independent interactions of G-domains with cell surface receptors which require spatially localized coactivation for optimal signal transduction.


Assuntos
Agrina/química , Receptores Colinérgicos/química , Animais , Membrana Basal/metabolismo , Western Blotting , Células COS , Células Cultivadas , Cromatografia em Agarose , Primers do DNA , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Proteínas da Matriz Extracelular/química , Modelos Biológicos , Modelos Genéticos , Estrutura Terciária de Proteína , Agregação de Receptores , Transfecção
6.
J Wildl Dis ; 34(3): 625-8, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9706574

RESUMO

An emaciated, moribund, male blue jay (Cyanocitta cristata) was collected in Georgia (USA) and died shortly after capture. Necropsy revealed nine large nematodes identified as Diplotriaena tricuspis in the thoracic and abdominal air sacs and within the pericardial sac. Multiple mycotic granulomas also were observed in the lungs and air sacs, and fungal culture of these lesions yielded pure growth of Aspergillus fumigatus. Histologic examination of the lungs revealed disseminated granulomatous inflammation containing both larvated nematode eggs and abundant fungal hyphae. This is the first description of concomitant A. fumigatus and D. tricuspis infection in a bird.


Assuntos
Aspergilose/veterinária , Doenças das Aves , Pneumopatias Fúngicas/veterinária , Pneumopatias Parasitárias/veterinária , Infecções por Nematoides/veterinária , Pneumonia/veterinária , Sacos Aéreos/microbiologia , Sacos Aéreos/parasitologia , Sacos Aéreos/patologia , Animais , Aspergilose/complicações , Aspergilose/microbiologia , Doenças das Aves/microbiologia , Doenças das Aves/parasitologia , Doenças das Aves/patologia , Aves , Evolução Fatal , Georgia , Pulmão/microbiologia , Pulmão/parasitologia , Pulmão/patologia , Pneumopatias Fúngicas/complicações , Pneumopatias Fúngicas/microbiologia , Pneumopatias Parasitárias/complicações , Pneumopatias Parasitárias/parasitologia , Masculino , Infecções por Nematoides/complicações , Infecções por Nematoides/parasitologia , Pneumonia/microbiologia , Pneumonia/parasitologia
7.
Toxicol Appl Pharmacol ; 149(2): 136-43, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9571981

RESUMO

We have investigated systematically the effects of short-term exposure to main stream cigarette smoke condensates (CSC-MS) on basal and inducible functional capacities of murine peritoneal exudate macrophages. Macrophages treated with CSC-MS form granules that fluoresce orange under blue excitation, consistent with the speculation that they are polycyclic aromatic hydrocarbons (PAH). CSC-MS selectively suppressed interferon gamma (IFN gamma) induction of four macrophage functional capacities: enhanced phagocytosis of immunoglobulin-opsonized sheep red blood cells, TPA-induced H2O2 production, class II major histocompatibility complex expression, and nitric oxide synthesis. In contrast, two macrophage functions that are not induced by IFN gamma, basal electron transport and LPS-induced TNF alpha production, were enhanced by treatment with CSC-MS. These results suggest that the suppressive effects of CSC-MS on macrophage responsiveness were selective and were not due to nonspecific inhibition of general functions such as RNA or protein synthesis. Since macrophage responsiveness to IFN gamma can result in induction of functional capacities that are fundamental to immunity, the data suggest that CSC-MS maybe deleterious to the general health of the smoker.


Assuntos
Interferon gama/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/imunologia , Poluição por Fumaça de Tabaco/efeitos adversos , Animais , Carcinógenos/efeitos adversos , Transporte de Elétrons , Feminino , Antígenos de Histocompatibilidade Classe II/biossíntese , Imunidade Celular/efeitos dos fármacos , Lipopolissacarídeos , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/biossíntese , Fagocitose/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Explosão Respiratória , Fator de Necrose Tumoral alfa/biossíntese
8.
J Zoo Wildl Med ; 28(3): 298-306, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9365943

RESUMO

Sixteen horned puffin (Fratercula corniculata) and six parakeet auklet (Cyclorrhynchus psittacula) chicks of various prefledging ages were caught in Alaska and transported to the North Carolina Zoological Park (USA) in August 1995. Six of the 16 puffin chicks died within a 5-day period beginning 2 days after their arrival into quarantine at the zoo. The birds that died were collected at a young age, weighed 45.4-65.7 g, and had been fed a diet of thawed frozen ocean silversides (Atherinidae) that was not supplemented with vitamins. Clinical signs were nonspecific, and gross necropsies, insecticide toxicology screens, and bacterial cultures were unremarkable. Microscopic examination of tissues from five of the six birds showed myocardial necrosis and degeneration suggestive of vitamin E deficiency and intestinal protozoa resembling Microsporidia. The mortality pattern and histopathologic lesions observed in this case support the use of selective age capture and vitamin supplementation for wild alcid chick collection.


Assuntos
Doenças das Aves/mortalidade , Deficiência de Vitamina E/veterinária , Animais , Animais de Zoológico , Doenças das Aves/diagnóstico , Doenças das Aves/patologia , Aves , Ceco/patologia , Enteropatias/parasitologia , Enteropatias/patologia , Enteropatias/veterinária , Intestinos/parasitologia , Intestinos/patologia , Fígado/patologia , Microsporida/isolamento & purificação , Microsporidiose/patologia , Microsporidiose/veterinária , Miocárdio/patologia , Necrose , Quarentena/veterinária , Deficiência de Vitamina E/diagnóstico , Deficiência de Vitamina E/mortalidade
9.
J Wildl Dis ; 33(3): 635-7, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9249713

RESUMO

To determine if Mycobacterium avium paratuberculosis has persisted in tule elk (Cervus elaphus nannodes) at Point Reyes National Seashore (California, USA), 100 fresh fecal samples were collected. Feces were cultured on a modified BACTEC 12B radiometric medium for detection of M. avium paratuberculosis. Four samples, coming from two separate groups of elk tested positive for M. avium paratuberculosis. Thus, a noninvasive technique was used to document the continued presence of M. avium paratuberculosis in elk at Point Reyes National Seashore. These findings document persistence of this organism for a period of at least 13 yr in a free ranging herd of elk, with a 6 yr absence of observed clinical signs.


Assuntos
Cervos , Fezes/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Paratuberculose/epidemiologia , Animais , California/epidemiologia , Meios de Cultura , Radiometria/veterinária
10.
Anal Chem ; 69(22): 4615-8, 1997 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-9375519

RESUMO

A reflectron is described which provides high-order kinetic energy focusing using a simple geometry that does not require a set of resistively coupled lens elements. The reflectron is implemented in an approximately 2.0 in (overall length) mass analyzer as part of an effort to provide highly miniaturized mass spectrometers that may be utilized as field-portable instruments for environmental analysis, biological agent detection, or diagnostics.


Assuntos
Espectrometria de Massas/instrumentação , Bradicinina/análise , Cinética , Matemática
11.
J Am Soc Mass Spectrom ; 7(6): 590-7, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24203431

RESUMO

Atandem reflectron time-of-flight mass spectrometer developed in our laboratory provides a unique opportunity to investigate the collision-induced dissociation of fullerene ions formed by matrix-assisted laser desorption/ionization (MALDI). Specifically, this opportunity arises from the ability to utilize high energy collisional activation (normally available only on tandem sector instruments by using continuous ionization techniques) for ions formed by pulsed laser desorption, whereas most MALDI time-of-flight instruments record product ion mass spectra of ions formed by metastable or postsource decay. In this study we investigate the products of mass-selected and collisionally activated C 60 (+) and C 70 (+) ions by using different target gases over a range of target gas pressures. In general, heavier target gases produce more extensive fragmentation and improve the mass resolution of lower mass ionic products because a greater portion of these ions are formed by single collisions. Additionally, the tandem time-of-flight instrument utilizes a nonlinear (curved-field) reflectron in the second mass analyzer that enables high energy collision-induced dissociation spectra to be recorded without scanning or stepping the reflectron voltage.

12.
Rapid Commun Mass Spectrom ; 9(14): 1356-61, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8534886

RESUMO

A time-of-flight mass spectrometer has been developed using a reflectron in which the voltages placed on the lens elements correspond to a function describing the arc of a circle. This curved-field reflectron enables acquisition of focused product-ion mass spectra at a single reflectron voltage. In this paper, we present results from this instrument for the amino acid sequencing of several peptides and describe the method of mass calibration.


Assuntos
Peptídeos/análise , Sequência de Aminoácidos , Angiotensina II/análise , Calibragem , Caseínas/análise , Dados de Sequência Molecular , Potenciometria , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/instrumentação , Substância P/análise
13.
Rapid Commun Mass Spectrom ; 8(9): 781-5, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7949338

RESUMO

The ability to simultaneously focus a wide mass range of metastable fragment ions formed after the initial ionization event in a matrix-assisted laser desorption/ionization time-of-flight mass spectrometer has been made possible by the development of a new type of ion reflector. This coaxially designed time-of-flight instrument employs a modified single stage reflector whose axial voltage gradient rises differentially in order to produce an alignment of energy focal points for product ions. In contrast, product-ion focusing in conventional constant field reflectors occurs over a broad range of distances from the reflectron exit. Approximately 90% of the product-ion mass spectrum can be collected without adjustment, thereby eliminating the need to scan the reflector voltage. Design considerations of the curved field reflectron, its calibration properties and representative metastable spectra of several peptides are discussed.


Assuntos
Espectrometria de Massas/instrumentação , Íons , Oligopeptídeos/análise , Peptídeos/química
15.
Rapid Commun Mass Spectrom ; 7(11): 1037-40, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8280914

RESUMO

A new type of curved-field reflectron has been developed for the energy focusing of ions formed after initial acceleration in time-of-flight (TOF) mass spectrometers. These include ions generated in the dissociation region of a tandem TOF, as well as metastable decay products formed in the field-free drift region prior to their reflection. Unlike conventional linear-field reflectrons, which focus product ions to different focal lengths that are proportional to the mass (energy) of the fragment, the new curved-field reflectron energy focuses all ions to within a small region near the exit of the reflectron. Thus, the collection of resolved fragment peaks is possible without scanning or stepping the potential gradient of the reflectron, enabling faster acquisition of the production spectrum and, more importantly, true multiplex recording of the spectra from each ionization event. Theoretical considerations of the design are discussed along with an evaluation of collision-induced dissociation data, demonstrating the performance of the new reflectron in a tandem TOF instrument.


Assuntos
Espectrometria de Massas/instrumentação
16.
Anal Chem ; 65(8): 1043-7, 1993 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-7684206

RESUMO

A compact, laser desorption tandem time-of-flight mass spectrometer is described. The instrument incorporates two dual-stage reflectron analyzers and a collision region for producing product ions by collision-induced dissociation. Selection of ions of a particular mass is accomplished by deflection of ions from stable trajectory angles entering the second reflectron, while the use of a pulsed valve for introduction of the collision gas obviates the need for differential pumping of the collision region. Initial results are presented, as well as a discussion for optimizing the performance of tandem time-of-flight instruments.


Assuntos
Espectrometria de Massas/instrumentação , Ácidos Cumáricos/análise , Gramicidina/análise , Rodaminas/análise
17.
Rapid Commun Mass Spectrom ; 6(4): 242-8, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1571597

RESUMO

A compact laser-desorption time-of-flight mass spectrometer using a 600 ps nitrogen laser and 1 Gsample/s transient recorder is described. The instrument incorporates two electrically-isolatable, reflecting flight tubes designed for subsequent configuration of the mass spectrometer as a tandem instrument. In this first report, we compare mass resolution in the laser-desorption mass spectra of an organic dye, sinapinic and caffeic acid matrices, and several small peptides. For directly desorbed ions, peak widths are generally of the order of 11 to 13 ns, so that mass resolution increases with increasing mass. For peptide ions in the range of 500 to 1000 u, formed by matrix-assisted desorption, peak widths range from 9.5 to 17.6 ns and increase with mass. However, better than unit mass resolution (1600 to 2400) is maintained throughout this mass range. Mass measurement accuracy is better than 0.1 u using a single calibration peak and a prompt start trigger pulse. Prospects for extending mass range and resolution are discussed.


Assuntos
Espectrometria de Massas/instrumentação , Ácidos Cumáricos/análise , Encefalina Metionina/análise , Encefalinas/análise , Lasers , Oligopeptídeos/análise , Precursores de Proteínas/análise
18.
Eur J Biochem ; 143(1): 63-7, 1984 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-6432537

RESUMO

The flash excitation of the pyridoxal 5'-phosphate cofactor of glycogen phosphorylase b by an ultraviolet laser produces a transient state from a proton transfer of the bound cofactor. The rate of decay of this transient state is sensitive to the ionization state of the cofactor. This proved a useful probe for the ionization state of the 5'-phosphate group of the cofactor on the binding by the enzyme of various substrates. The decay rate data show, for the binding of glucose 1-phosphate, a partially negative 5'-HPO4- and evidence for a PO4-PO4 interaction. The data is interpreted in terms of a dynamic shift of substrates at the active site.


Assuntos
Lasers , Fosforilase b/metabolismo , Fosforilases/metabolismo , Monofosfato de Adenosina/metabolismo , Animais , Sítios de Ligação , Fenômenos Químicos , Físico-Química , Glucofosfatos/metabolismo , Espectroscopia de Ressonância Magnética , Fosfato de Piridoxal/metabolismo , Coelhos , Espectrofotometria
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