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1.
Brain Inj ; 34(3): 369-374, 2020 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-32026729

RESUMO

Objective: Despite widespread use of baseline neurocognitive testing in concussion management, suboptimal performance due to sandbagging still readily occurs without detection. The purpose of this study is to determine CNS Vital Signs validity indicator accuracy in detecting coached sandbagging compared to controls.Method: We compared rates of invalidity and domain composite scores for neurocognitive test performance between two groups of twenty-five college-aged students (age = 20.8 ± 1.1 years, range 18-25, 48% female) completing CNS Vital Signs instructed to either 1) give their best effort (control) or, 2) give suboptimal performance (sandbag). The sandbagging group was given standardized instructions on how to sandbag without detection. All participants rated their effort after completing on a Visual Analog Scale (0-100 mm).Results: Built in invalidity indicators successfully identified 68.0% of sandbaggers, while only 12% in the control group presented with invalid scores. Participants in the sandbagging group on average reported significantly lower effort (sandbag: 51.0 ± 21.0, control: 86.0 ± 12.0, p < .001)Conclusions: Built-in CNS Vital Signs validity indicators have an overall high accuracy in identifying those attempting to purposefully sandbag and are comparable to other computerized neurocognitive tests. Given that 32% of intentional sandbaggers went undetected, clinicians should consider additional safeguards to detect these individuals at baseline.


Assuntos
Concussão Encefálica/diagnóstico , Concussão Encefálica/fisiopatologia , Testes Neuropsicológicos , Sinais Vitais , Adolescente , Adulto , Traumatismos em Atletas/diagnóstico , Traumatismos em Atletas/fisiopatologia , Feminino , Humanos , Masculino , Testes de Estado Mental e Demência , Reprodutibilidade dos Testes , Estudantes/psicologia , Adulto Jovem
2.
Biochim Biophys Acta ; 949(1): 132-7, 1988 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-3334848

RESUMO

Studies have been conducted on the absorption, fluorescence excitation and fluorescence emission of mitoxantrone, an important antineoplastic agent. Mitoxantrone has been found to fluoresce with excitation maxima at 610 and 660 nm and emission maximum at 685 nm. Further characterizations of the fluorescence were undertaken to study its usefulness in biological studies. Mitoxantrone fluorescence intensity is altered by pH and the emission spectrum is red-shifted by DNA. Furthermore, the fluorescence polarization is enhanced by DNA, confirming the binding of the antitumor agent to DNA. The fluorescence spectra are slightly modified by changes in ionic strength and the addition of albumin. Data establishing the usefulness of fluorescence to measure serum concentrations in the range of 0.0 to 100 nM are presented. Such determinations can distinguish serum mitoxantrone from its non-fluorescent primary metabolite.


Assuntos
Mitoxantrona , Animais , Carcinoma de Ehrlich/metabolismo , DNA de Neoplasias/metabolismo , Doxorrubicina , Humanos , Camundongos , Camundongos Endogâmicos CBA , Mitoxantrona/sangue , Mitoxantrona/metabolismo , Albumina Sérica/metabolismo , Espectrometria de Fluorescência , Baço/metabolismo
3.
J Parasitol ; 69(2): 387-90, 1983 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6854478

RESUMO

Our field study did not support anecdotal claims alleging pathogenicity on the part of P. cylindraceus in starlings. Within-clutch analysis of nestling starling weights (n = 25) over time showed that P. cylindraceus had no effect on position in clutch relative to siblings. Parasitized nestlings tended to weigh more than control siblings. Within-sex analysis of wild adult starling weight (n = 103) showed no difference between animals with acanthocephalans and uninfected animals and weight was not related to intensity of infection. Host response to the proboscis was limited to immediately-surrounding tissue (90 microns). Other observations made in this study included the following: (1) no evidence for deleterious intraspecific interaction among adult P. cylindraceus in starlings; (2) no apparent interspecific interactions between P. cylindraceus and (unidentified) cestode species in starlings; and (3) copulatory caps on male P. cylindraceus may be a response to environmental deterioration in dead hosts.


Assuntos
Acantocéfalos/patogenicidade , Aves/parasitologia , Intestino Delgado/parasitologia , Acantocéfalos/anatomia & histologia , Animais , Cestoides/fisiologia , Feminino , Interações Hospedeiro-Parasita , Mucosa Intestinal/parasitologia , Masculino
7.
J Prosthet Dent ; 56(3): 322-6, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3018236

RESUMO

In two separate but related studies, different forms of hydroxyapatite were implanted into the extraction sockets of human teeth to delay alveolar resorption and to form the background for a comparison of the treatment modalities. The significant differences in the treatment modalities and the postoperative sequelae seem to merit this report. The implantation of the particles appears to be clinically, a more expedient procedure than the implantation of cones. The time required to select an appropriate-sized cone, modify the cone as needed to achieve a snug fit into the extraction socket, and seat the cone deeply enough in the extraction socket to assure at least 2 mm of bone above the top of the cone implant was significantly greater than the time required to fit and pack particles into an extraction socket. None of the postimplantation problems encountered with cones was encountered in using the particle implants. The postimplantation problems encountered with cones included submucosal prominence, erosion through the mucosa (dehiscence), migration, loss of the implant, or surgical maintenance or resubmergence. Data from these two studies suggest that the implantation of particles into the extraction sockets of human teeth to delay alveolar ridge resorption is a more prudent, forgiving, considerate, problem-free, and predictable procedure than the implantation of cones.


Assuntos
Alveoloplastia/métodos , Reabsorção Óssea/prevenção & controle , Hidroxiapatitas , Próteses e Implantes , Adulto , Durapatita , Feminino , Humanos , Doenças Maxilomandibulares/prevenção & controle , Arcada Edêntula/cirurgia , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula , Fatores de Tempo
8.
Exp Brain Res ; 52(1): 1-5, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6628589

RESUMO

Nine-month-old rats were injected with 5 microCi 3H-thymidine (3H-Tdr) and allowed to survive for 20 days. In light-microscopic radioautographs, labeled cells were found in the granule cell layer of the hippocampus. Analysis of electron micrographs of the labeled cells, taken from re-embedded 1.5 micron radioautographic sections, clearly demonstrated their neuronal nature with synapses along their cell bodies and dendrites. Our results indicate that 0.025% of the granule neurons are heavily labeled in the dorsal hippocampus. Electron microscopy of re-embedded light-microscopic radioautographic sections confirms that granule neurons in the rodent are newly formed up until 9 months after birth.


Assuntos
Granulócitos/fisiologia , Hipocampo/citologia , Neurônios/fisiologia , Ratos/fisiologia , Envelhecimento , Animais , Autorradiografia , Divisão Celular , Granulócitos/ultraestrutura , Masculino , Ratos Endogâmicos , Timidina , Trítio
9.
J Neurosci ; 4(6): 1429-41, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6726341

RESUMO

Ultrastructural identification of mitotic neuronal precursors beneath the basal hippocampal granule cell layer was made using electron micrographs of [3H]thymidine-labeled cells. Ultrathin sections were obtained by a method that allows serial thin sectioning of reembedded sections previously prepared for light microscopic radioautography. The electron microscopic observations reported in this study reveal: (1) that a steady rate of granule cell neurogenesis occurs during the first year of a rodent's life; (2) that newly formed granule neurons in the dentate gyrus of the newborn mouse and adult rat are a result of neuroblast division; and (3) two distinct classes of mitotic cells can be identified during the peak period of postnatal neurogenesis--those with synapses on their cell bodies and processes and those with no synapses or processes.


Assuntos
Hipocampo/ultraestrutura , Animais , Animais Recém-Nascidos , Hipocampo/citologia , Hipocampo/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos , Microscopia Eletrônica , Mitose
10.
Anat Rec ; 210(1): 101-14, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6486477

RESUMO

The developing inner ear of the teleost, Brachydanio rerio, provides an opportunity for observing an epithelial fusion between the apical surfaces of apposed epithelia in a vertebrate embryo in vivo. The developing otocyst was filmed for periods up to 4 days in unanesthetized embryos, and specimens were fixed at intervals and processed for light microscopy, TEM, and SEM. The semicircular canals are formed as a consequence of the union between the tips of three cylindrical projections from the wall of the otocyst, which grow toward corresponding bulges of a projection from the lateral wall. The epithelial cells covering the projections contain extensive rough endopasmic reticulum, exhibit apical junctional complexes, and are not underlain by a basal lamina. The core of each projection contains large amounts of flocculent and fibrillar extracellular material. After a period of growth and elongation, the tip of each projection contacts, and adheres to, the appropriate bulge to create a circular, flattened, bilayered, epithelial plate. Small, focal junctions form between the apposed apical cell surfaces within the plate during this period, but they are not numerous. Junctional complexes do develop, however, between apposed cells at the periphery of the plate. After 1-2 hours, the basal surface of the plate exhibit considerable alteration in contour. Adjacent cells within the plate then separate to allow continuity of the connective tissue components of the two structures. The observations of this study indicate that following an initial period of contact and adhesion, cellular reorientation and changes in junctional contacts between adjacent cells within the epithelial plate, rather than cell degeneration, are responsible for perforation of the plate.


Assuntos
Peixes/embriologia , Canais Semicirculares/embriologia , Animais , Epitélio/embriologia , Microscopia Eletrônica , Filmes Cinematográficos , Canais Semicirculares/ultraestrutura , Fatores de Tempo
11.
J Prosthet Dent ; 60(4): 479-83, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3183985

RESUMO

Presurgical planning for submerged implant location and angulation within bone relative to the opposing occlusion is important for the prosthodontist. This information is accurately communicated to the surgeon by using a surgical template. A technique for fabrication of the template is described.


Assuntos
Implantação Dentária Endóssea/instrumentação , Implantação Dentária Endóssea/métodos , Desenho de Equipamento , Humanos , Modelos Dentários , Planejamento de Assistência ao Paciente
12.
J Prosthet Dent ; 57(4): 484-7, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3553570

RESUMO

A technique allowing accurate alignment and interocclusal spacing of the coping insert for submerged implants has been described. Transferring the coping from the mouth to the master cast will provide predictable treatment results and is particularly useful when intraoral visualization is difficult.


Assuntos
Implantação Dentária Endóssea , Técnica de Moldagem Odontológica , Encaixe de Precisão de Dentadura , Planejamento de Dentadura , Humanos
13.
J Rheumatol ; 14(1): 9-11, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3033240

RESUMO

When mediators of inflammation such as complement component C5a or leukotriene B4 are introduced into an air pouch created in mice, these mediators induce the migration of neutrophils into the air pouch. Pretreatment of mice with low doses of methotrexate inhibits leukotriene B4 or C5a induced neutrophil migration into the air pouch. Inhibition of neutrophil chemotaxis by methotrexate may, at least in part, account for the rapid onset of antiinflammatory activity that was observed in clinical trials with methotrexate in rheumatoid arthritis.


Assuntos
Quimiotaxia de Leucócito/efeitos dos fármacos , Complemento C5/administração & dosagem , Leucotrieno B4/farmacologia , Metotrexato/farmacologia , Neutrófilos/efeitos dos fármacos , Animais , Complemento C5a , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos
14.
J Rheumatol ; 18(6): 855-60, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1895266

RESUMO

CL 306,293, a substituted quinoline carboxylic acid at a daily oral dose between 1.5 and 3.0 mg/kg suppressed the inflammation and joint destruction (radiological criteria) associated with both developing and established adjuvant arthritis. When a weekly oral dosing regimen was used, joint destruction was attenuated when this agent was administered at a dose of 50 to 200 mg/kg. Inflammation associated with a delayed type hypersensitivity reaction in dogs was suppressed at a daily dose of 0.25 mg/kg or a weekly dose of 1 mg/kg. At efficacious doses, CL 306,293 had no effects on cyclooxygenase or lipoxygenase activities nor did it have an effect on carrageenin induced paw edema. In acute tests, the compound was not ulcerogenic. The above observations indicate that the antiinflammatory effects of CL 306,293 are distinct from those observed with nonsteroidal antiinflammatory agents. Mechanistic studies conducted and to be published indicate that CL 306,293 down regulates T cell function and this mechanism may account, at least in part, for the antiinflammatory and antiarthritic properties observed in animal models of inflammation and joint destruction.


Assuntos
Aminoquinolinas/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Artrite Experimental/tratamento farmacológico , Compostos de Bifenilo/farmacologia , Administração Oral , Aminoquinolinas/administração & dosagem , Aminoquinolinas/uso terapêutico , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/uso terapêutico , Artrite Experimental/patologia , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/patologia , Compostos de Bifenilo/administração & dosagem , Compostos de Bifenilo/uso terapêutico , Cães , Relação Dose-Resposta a Droga , Inflamação/tratamento farmacológico , Inflamação/patologia , Masculino , Ratos , Ratos Endogâmicos , Linfócitos T/efeitos dos fármacos
15.
Anal Chem ; 69(14): 2716-26, 1997 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-9230680

RESUMO

Calicheamicin derivatives (MW approximately 1500) and monoclonal antibodies (MoAbs) conjugated to calicheamicin derivatives (MW approximately 150,000) were analyzed by UV-MALDI/MS, IR-MALDI/MS, and ESI/MS. These materials are potent anticancer agents. Calicheamicin derivatives and conjugates rapidly degrade upon UV irradiation but are relatively stable during IR irradiation and under ESI conditions. A unique feature of IR-MALDI/MS is a 2 times enhancement in resolution relative to UV-MALDI/MS for masses above approximately 50,000 Da resulting in a molecular ion envelope containing a series of partially resolved peaks of the calicheamicin-MoAb conjugates. The mass shift difference between the peak maxima corresponded to the mass change due to the covalent addition of calicheamicin derivatives to the monoclonal antibody. The distribution of the calicheamicin derivatives in the monoclonal antibodies was computed by deconvoluting the partially resolved peak envelope. A unique feature of the ESI mass spectra, under unit resolution conditions, is that the distribution of the carbohydrates can be well resolved for pure MoAbs and can be only partially resolved for conjugated MoAbs. Average loading values for calicheamicia derivatives when conjugated to MoAbs were computed from UV-MALDI/MS, IR-MALDI/MS, and ESI/MS data and the results compared with the average loading values obtained by UV absorption spectrometry. Very low average loading values were computed from UV-MALDI/MS data due to the degradation of the conjugated calicheamicin derivatives during the UV irradiation process. The IR-MALDI/MS average loading values, obtained with glycerol as the matrix, were consistent with the UV absorption spectrometry values for conjugates having hydrolytically stable linkers, but not when the linker contained a hydrolytically labile hydrazone. ESI/MS average loading values were generally lower than the corresponding values obtained by IR-MALDI/MS. The average loading values and distributions obtained using IR-MALDI/MS were more reliable than the corresponding ESI/MS values because the partially resolved, singly and doubly charged peaks in the IR-MALDI spectra can be mathematically deconvoluted, while the overlapping, highly multiply charged peaks of the electrospray spectra can only be partially deconvoluted.


Assuntos
Aminoglicosídeos , Antibacterianos/química , Antibióticos Antineoplásicos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Antibacterianos/análise , Antibióticos Antineoplásicos/análise , Anticorpos Monoclonais/química , Sequência de Carboidratos , Sistemas de Liberação de Medicamentos , Raios Infravermelhos , Espectrometria de Massas , Dados de Sequência Molecular , Estrutura Molecular , Raios Ultravioleta
16.
Diabetes Metab Rev ; 7(2): 93-104, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1794260

RESUMO

Gestational diabetes mellitus (GDM) is associated with increased risk of poor outcomes for the pregnancy. It is a strong risk factor for subsequent diabetes. The epidemiology of GDM in African-American women is not well known. It has not been demonstrated that their risk factors are similar in character and weight to those among White women. There is considerable multicollinearity among GDM risk factors such as age, parity, obesity, hypertension, and family history of diabetes, and this needs to be sorted out. This review is based on the results of a nested case-control study to evaluate the frequency of, and the relationships of the known risk factors with, the onset of GDM among African-American women. All cases of GDM within a cohort of women seen at any of the county health department clinics in Jefferson County, Alabama from 1981 to 1987 were identified. The cohort represents approximately 63% of all African-American pregnancies in the county during the period. With few exceptions (5.1% based on fasting plasma glucose greater than or equal to 120 mg/dl), potential GDM cases (7.1%) were selected on the basis of a 2 h post 100 g carbohydrate meal screening plasma glucose measure at their second prenatal visit and again at 28-32 weeks greater than or equal to 115 mg/dl and diagnosed on the basis of the results of an oral glucose tolerance test (OGTT) using the criteria of O'Sullivan and Mahan. Women with any prior history of diabetes (even in pregnancy), 1.6%, were excluded. The frequency of the new diagnosis of GDM among African-American women in this pregnancy in the cohort was 2.5% of pregnancies and 3.4% of women, which is similar to the values reported in the other studies. Controls were selected from women with negative screening tests who delivered after a GDM subject. The results reported in this paper reflect 358 cases (86% of all eligible GDM cases identified) and 273 controls. Cases were significantly older (28.3 vs. 21.7 years), of higher gravidity (2.7 vs. 1.9), more obese (76.7 vs. 61.7 kg), gained weight more rapidly (0.34 vs. 0.28 kg/week), had more hypertension in this pregnancy (28.2 vs. 2.6%), and there was a higher proportion with a family history of diabetes (41.3 vs. 16.5%) (p less than 0.001 for all comparisons). Because there were significant correlations among the risk factors in both cases and controls, multivariable logistic regression analyses were performed.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
População Negra , Diabetes Gestacional/etiologia , Adulto , Alabama , Análise de Variância , Peso ao Nascer , Peso Corporal , Estudos de Casos e Controles , Feminino , Humanos , Recém-Nascido , Gravidez , Análise de Regressão , Fatores de Risco
18.
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