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1.
Phys Rev Lett ; 126(14): 141801, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33891447

RESUMO

We present the first results of the Fermilab National Accelerator Laboratory (FNAL) Muon g-2 Experiment for the positive muon magnetic anomaly a_{µ}≡(g_{µ}-2)/2. The anomaly is determined from the precision measurements of two angular frequencies. Intensity variation of high-energy positrons from muon decays directly encodes the difference frequency ω_{a} between the spin-precession and cyclotron frequencies for polarized muons in a magnetic storage ring. The storage ring magnetic field is measured using nuclear magnetic resonance probes calibrated in terms of the equivalent proton spin precession frequency ω[over ˜]_{p}^{'} in a spherical water sample at 34.7 °C. The ratio ω_{a}/ω[over ˜]_{p}^{'}, together with known fundamental constants, determines a_{µ}(FNAL)=116 592 040(54)×10^{-11} (0.46 ppm). The result is 3.3 standard deviations greater than the standard model prediction and is in excellent agreement with the previous Brookhaven National Laboratory (BNL) E821 measurement. After combination with previous measurements of both µ^{+} and µ^{-}, the new experimental average of a_{µ}(Exp)=116 592 061(41)×10^{-11} (0.35 ppm) increases the tension between experiment and theory to 4.2 standard deviations.

2.
Surv Ophthalmol ; 34(1): 59-64, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2552598

RESUMO

A 28-year-old man with a previous history of Neissena infection presented with diminished vision, disc swelling, and panuveitis. Serologic tests revealed positive titers for both HIV and syphilis. Current epidemiology and treatment of such cases are discussed.


Assuntos
Infecções por Retroviridae/etiologia , Síndrome da Imunodeficiência Adquirida/complicações , Adulto , Soropositividade para HIV/diagnóstico , Humanos , Masculino , Doenças do Nervo Óptico/complicações , Sorodiagnóstico da Sífilis , Uveíte/complicações , Acuidade Visual
3.
Artigo em Inglês | MEDLINE | ID: mdl-8734700

RESUMO

Vasoocclusive involvement of bones is a common cause of acute morbidity in patients with sickle cell hemoglobinopathy. Although the literature contains only two reports of infarction of the mandible in sickle cell vasooccusive crisis, earlier authors were often limited to the clinical examination as their primary or only diagnostic method. This article presents a sickle cell patient in vasoocclusive crisis who subsequently developed infarction of the right mandible without an infectious or inflammatory cause and was ultimately diagnosed by nuclear bone imaging scans.


Assuntos
Anemia Falciforme/complicações , Medula Óssea/irrigação sanguínea , Infarto/diagnóstico por imagem , Doenças Mandibulares/diagnóstico por imagem , Doenças Mandibulares/etiologia , Adulto , Diagnóstico Diferencial , Radioisótopos de Gálio , Humanos , Masculino , Osteomielite/diagnóstico por imagem , Cintilografia , Tecnécio
7.
Mol Cell Biochem ; 59(1-2): 11-32, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6323961

RESUMO

Investigations in numerous laboratories have characterized a salt transport system, present in many animal cell types, which catalyzes the transmembrane transport of NaCl and KCl in a tightly coupled process. The system is inhibited by loop diuretics such as furosemide and bumetanide. This transport system has been designated the loop diuretic-sensitive NaCl/KCl symporter. It has been implicated in transepithelial salt secretion and absorption as well as in cell volume regulation, and it may be defective in patients suffering from essential hypertension. This review serves to evaluate research conducted to date regarding the mechanism, mode of regulation, and physiological significance of the transport system. Ion binding specificities and absolute binding constants for all three naturally occurring ions have been determined in one cell system, the MDCK kidney epithelial cell line. In that same cell line, substrate binding was shown to exhibit apparent cooperativity. although a few reports suggest unidirectional transport of ions via this system under certain conditions, the consensus of reports indicates fully reversible, bidirectional salt transport with the direction of net flux determined by the magnitudes of the gradients of the three transported ions. Growth of cells in media containing a low concentration of K+ (less than 0.25 mM) allows selection of mutants lacking or defective in the symporter. Kinetic analyses with the MDCK cell line have shown that the symporter catalyzes accelerative exchange transport. However, exchange transport of one ion in the absence of one of the other two ionic substrates has not been documented. Comparison with other well-characterized transmembrane transport systems has shown that the characteristics of the NaCl/KCl symporter most resemble those of two-species facilitators (chemiosmotically-coupled symporters) found in prokaryotes and eukaryotes alike. these two-species facilitators consist of a single transmembrane protein and may function by a carrier-type mechanism as originally proposed by Peter Mitchell. A molecular model for the NaCl/KCl symporter is presented and discussed. Activation of symport activity requires ATP and probably occurs by a protein kinase-catalyzed mechanism. In some cell types activation is cyclic AMP dependent. ATP hydrolysis is not stoichiometric with transport. Phosphorylation of an integral membrane protein with an apparent size of 240 000 daltons correlates with activation of transport. It is postulated that this protein is the loop diuretic-sensitive NaCl/KCl symporter.


Assuntos
Diuréticos/farmacologia , Cloreto de Potássio/metabolismo , Cloreto de Sódio/metabolismo , Trifosfato de Adenosina/fisiologia , Animais , Transporte Biológico/efeitos dos fármacos , Linhagem Celular , AMP Cíclico/fisiologia , Rim/citologia , Rim/metabolismo , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Mutação , Especificidade por Substrato , Sulfonamidas
8.
Implant Dent ; 7(3): 221-5, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9823111

RESUMO

Computerized tomography (CT) scanning, now widely used for the diagnosis and treatment planning of dental implant sites, can be more specifically useful with integrated computer software. In this instance, the potentially critical incisive foramen area at the premaxilla is analyzed to better under stand its configuration and volume relative to the placement of root-form implants.


Assuntos
Implantação Dentária Endóssea , Incisivo , Maxila/anatomia & histologia , Adulto , Idoso , Feminino , Humanos , Arcada Parcialmente Edêntula/diagnóstico por imagem , Masculino , Maxila/diagnóstico por imagem , Pessoa de Meia-Idade , Planejamento de Assistência ao Paciente , Tomografia Computadorizada por Raios X
9.
Ann Ophthalmol ; 14(11): 1051-4, 1982 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6983850

RESUMO

In a 31-year-old man, metastatic Aspergillus endophthalmitis developed after intravenous cocaine injection. His reluctance to admit to drug abuse resulted in delay of diagnostic and curative vitrectomy. Metastatic osteomyelitis also developed, underscoring the need for careful surveillance for other systemic manifestations of fungemia. We believe this to be the first published case in which useful vision was salvaged in an eye afflicted by metastatic Aspergillus endophthalmitis.


Assuntos
Aspergilose , Cocaína , Endoftalmite/etiologia , Transtornos Relacionados ao Uso de Substâncias/complicações , Adulto , Aspergilose/diagnóstico , Endoftalmite/diagnóstico , Humanos , Injeções Intravenosas , Masculino
10.
Infect Immun ; 57(12): 3808-15, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2807548

RESUMO

We cloned genes that code for Treponema hyodysenteriae antigens into Escherichia coli with the purpose of identifying protective antigens for vaccine development. Three different genomic libraries were screened with various antisera reactive with T. hyodysenteriae antigens. The cloned antigens and corresponding native T. hyodysenteriae antigens were analyzed for molecular size, serum reactivity, solubility in sarcosine, and segregation during phase partitioning with the nonionic detergent Triton X-114. The results from these analyses suggested that the gene products were components of either the cytoplasmic membrane, periplasm, or endoflagella of T. hyodysenteriae. The cloned antigens were tested as vaccine candidates in a CF-1 mouse model of T. hyodysenteriae infection and immunity. Intraperitoneal injection of crude E. coli extracts containing cloned antigens did not protect mice from challenge. However, serum from mice injected with a crude extract of an E. coli clone which expressed an endoflagellar antigen killed T. hyodysenteriae in vitro. Partially purified preparations of this cloned endoflagellar antigen protected mice against oral challenge with both the homologous serotype (B204) and a heterologous serotype (B234) of T. hyodysenteriae. These results suggest that the endoflagellar proteins could be used as an effective subunit vaccine against T. hyodysenteriae.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/imunologia , Treponema/imunologia , Infecções por Treponema/prevenção & controle , Animais , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/genética , Western Blotting , Clonagem Molecular , Flagelos/imunologia , Flagelos/ultraestrutura , Genes Bacterianos , Biblioteca Genômica , Camundongos , Peso Molecular , Treponema/genética , Treponema/ultraestrutura , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia
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