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1.
BMJ Mil Health ; 2023 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-37709507

RESUMEN

Whole blood transfusion is being increasingly used for trauma resuscitation, particularly in military settings. Low-titre group O whole blood simplifies the logistical challenges and maximises the benefits of blood transfusion when compared with component therapy in austere battlefield conditions. Screening protocols and blood testing requirements for prescreened donors in walking blood banks (WBBs), which are used for emergency transfusions, are established by both the USA and most partner nations, though they are not necessarily uniform across these combined forces. Interoperability and standardisation of blood bank resources and protocols across allied forces in multinational military operations, including uniformity in screening processes, collection methods and storage is essential to the provision of safe and effective blood product transfusions in this austere setting. Predeployment screening, multinational training exercises and universal WBB sets with instructions in multiple languages can help enhance the interoperability of combined multinational operations and create a more efficient WBB system. Standardisation of blood collection, nomenclature, equipment and screening practices will allow for the most optimal utilisation of whole blood resources across a multinational battlefield.

2.
Astrobiology ; 8(2): 253-66, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18393691

RESUMEN

The jarosite group minerals have received increasing attention since the discovery of jarosite on the martian surface by the Mars Exploration Rover Opportunity. Given that jarosite can incorporate foreign ions within its structure, we have investigated the use of jarosite as an indicator of aqueous and biological processes on Earth and Mars. The use of laser desorption Fourier transform mass spectrometry has revealed the presence of organic matter in several jarosite samples from various locations worldwide. One of the ions from the natural jarosites has been attributed to glycine because it was systematically observed in combinations of glycine with synthetic ammonium and potassium jarosites, Na(2)SO(4) and K(2)SO(4). The ability to observe these organic signatures in jarosite samples with an in situ instrumental technique, such as the one employed in this study, furthers the goals of planetary geologists to determine whether signs of life (e.g., the presence of biomolecules or biomolecule precursors) can be detected in the rock record of terrestrial and extraterrestrial samples.


Asunto(s)
Exobiología , Medio Ambiente Extraterrestre/química , Compuestos Férricos/análisis , Glicina/análisis , Marte , Espectrometría de Masas , Sulfatos/análisis , Análisis de Fourier , Rayos Láser , Origen de la Vida
3.
Biochemistry ; 42(32): 9761-70, 2003 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-12911319

RESUMEN

A number of common promoter elements that drive transcription of redox sensitive genes have runs of guanines in their transcription factor recognition sequence. A paradox exists insomuch that the same guanine runs necessary for transcription factor recognition are thermodynamically prone to oxidative modification, potentially altering the binding affinity of transcription factors. 7,8-Dihydro-8-oxo-2'-deoxyguanosine (8-oxo-dG) is a common oxidative modification of guanine that is generated by a variety of metals and reactive oxygen species. We have used the p50 subunit of the NF-kappaB transcription factor to show that oxidation of guanine to 8-oxo-dG at sites critical for protein recognition impacts transcription factor binding affinity differently depending upon the site of oxidation. It can be argued that the impact of such oxidation will be minimal in repair proficient cells. Therefore, we have developed an assay to assess the ability of these lesions to be shielded by transcription factor binding from recognition and repair by base excision repair (BER) enzymes. In this study, 8-oxo-dG was substituted for guanine at sites G(1)-G(4) in the NF-kappaB sequence 5'-d(AGTTGAG(1)G(2)G(3)G(4)ACTTTCCCAGCC)-3'. We have observed that substitution of 8-oxo-dG at the G(1) site increases p50 binding affinity by approximately 2.5-fold compared to that of the unmodified DNA sequence, while substitution at G(3) reduces the binding affinity by approximately 4-fold. Substitution of 8-oxo-dG at the G(2) and G(4) sites had a minimal impact on p50 binding affinity. Both Escherichia coli fapy glycosylase (Fpg) and human 8-oxo-DNA glycosylase (hOGG1) recognized and cleaved 8-oxo-dG at all four sites within the promoter element. The addition of the p50 transcription factor shielded these lesions from cleavage by the glycosylase in a manner that correlated with the binding affinities of p50 for the different modified sites. These data imply that lesion formation in DNA response elements can modulate gene transcription during oxidative events and that protein binding to these modified sites may allow these lesions to persist on a time scale that impacts global cellular gene transcription.


Asunto(s)
Reparación del ADN , Desoxiguanosina/análogos & derivados , Guanina/análogos & derivados , Guanina/química , Guanina/metabolismo , FN-kappa B/metabolismo , Transcripción Genética/fisiología , 8-Hidroxi-2'-Desoxicoguanosina , Secuencia de Bases , Sitios de Unión , Secuencia de Consenso , ADN-Formamidopirimidina Glicosilasa , Desoxiguanosina/química , Desoxiguanosina/metabolismo , Ensayo de Cambio de Movilidad Electroforética , Proteínas de Escherichia coli/metabolismo , Humanos , N-Glicosil Hidrolasas/antagonistas & inhibidores , N-Glicosil Hidrolasas/metabolismo , FN-kappa B/química , FN-kappa B/genética , Oxidación-Reducción , Regiones Promotoras Genéticas , Unión Proteica , Subunidades de Proteína , Factores de Tiempo
4.
Behav Res Ther ; 40(8): 947-59, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12186357

RESUMEN

The present study examined the factor structure, internal consistency, and construct validity of the parent version of the Social Competence and Behavior Evaluation-30 for preschoolers (SCBE-30; LaFreniere, P. J. (1990). Social competence and behavior evaluation-30. Unpublished measure.), an adaptation of the validated teacher version of the same measure (LaFreniere & Dumas, Psychol. Asses. 8 (1996) 369). The parent version of the SCBE-30 is a 30-item Likert rating scale questionnaire designed to assess patterns of anxiety/withdrawal, anger/aggression, and social competence. Principal components analysis was used to identify the factor structure of the parent version of the SCBE-30 (N = 218 preschool children). To assess construct validity, a compliance task was utilized to determine whether children identified as high on anxiety/withdrawal, anger/aggression, or social competence with the parent version of the SCBE-30 (n = 20 for each group) could be distinguished behaviorally on several observational variables. Principal components analysis identified three factors accounting for 44% of the variance. Ten items positively loaded onto each factor and matched conceptual expectations. A between-subjects MANOVA demonstrated significant group differences in observed child behaviors including compliance, noncompliance, subtypes of noncompliance, and aversive behavior. Results of the current study suggested that the parent version of the SCBE-30 demonstrated both internal consistency and construct validity, and findings paralleled many of the results from LaFreniere and Dumas' validation of the teacher version of the SCBE-30.


Asunto(s)
Agresión , Ansiedad/diagnóstico , Conducta Infantil/psicología , Socialización , Encuestas y Cuestionarios , Preescolar , Diagnóstico Diferencial , Humanos , Reproducibilidad de los Resultados
5.
Child Dev ; 72(5): 1347-66, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11700636

RESUMEN

For two cohorts of children from low- to moderate-income families, time-use diaries of television viewing were collected over 3 years (from ages 2-5 and 4-7 years, respectively), and tests of reading, math, receptive vocabulary, and school readiness were administered annually. Relations between viewing and performance were tested in path analyses with controls for home environment quality and primary language (English or Spanish). Viewing child-audience informative programs between ages 2 and 3 predicted high subsequent performance on all four measures of academic skills. For both cohorts, frequent viewers of general-audience programs performed more poorly on subsequent tests than did infrequent viewers of such programs. Children's skills also predicted later viewing, supporting a bidirectional model. Children with good skills at age 5 selected more child-audience informative programs and fewer cartoons in their early elementary years. Children with lower skills at age 3 shifted to viewing more general-audience programs by ages 4 and 5. The results affirm the conclusion that the relations of television viewed to early academic skills depend primarily on the content of the programs viewed.


Asunto(s)
Evaluación Educacional/estadística & datos numéricos , Familia/etnología , Desarrollo del Lenguaje , Pobreza/psicología , Televisión , Niño , Preescolar , Etnicidad/estadística & datos numéricos , Femenino , Estudios de Seguimiento , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Estudios Longitudinales , Masculino , Modelos Estadísticos , Pobreza/estadística & datos numéricos , Factores de Tiempo , Estados Unidos/epidemiología
6.
J Fla Med Assoc ; 82(3): 199-201, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7738524

RESUMEN

Two thousand thirty-eight years later, in the setting of a similar care presentation, a physician would take a detailed history and perform a clinical and neurological examination. A preliminary diagnosis would be entertained and followed by electroencephalography and magnetic resonance of the brain with and without paramagnetic contrast for diagnostic confirmation. The proper medical or surgical treatment would then be instituted. A reconstruction of the clinical history of Julius Caesar (100-44 B.C.) has been attempted from available information from literature. Although a definite conclusion obviously cannot be made, a differential diagnosis provided with a tentative hypothesis is presented. The patient had late onset of seizures in the last two years of his life, headaches, personality changes. Upon reexamination of existing Julius Caesar iconography, busts, statues and minted coins no skull deformities have been noted. Identification of a skull deformity as described by Suetonius would have confirmed the suspicion of meningioma involving the convexity of the cerebral hemispheres. Meningioma or slow-growing supratentorial glioma may well have been responsible for this man's illness. Who knows how the course of history might have been changed... Probably not at all.


Asunto(s)
Neoplasias Encefálicas/historia , Epilepsia/historia , Personajes , Historia Antigua , Humanos , Masculino , Mundo Romano
7.
J Clin Endocrinol Metab ; 80(2): 595-602, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7852526

RESUMEN

Gallium nitrate is a potent antiresorptive drug that has been extensively tested in patients with accelerated bone turnover. We have evaluated the effects of this new agent in a pilot multicenter trial of 49 patients with advanced Paget's disease of bone. Patients were randomized to receive 0.05, 0.25, or 0.5 mg/kg.day gallium nitrate administered by sc injection in two 14-day cycles. Serum alkaline phosphatase, fasting 2-h urinary hydroxyproline and N- telopeptide collagen cross-links excretion, and quality of life were assessed every 2 weeks for 12 weeks. The group mean alkaline phosphatase activity at baseline was 854 +/- 100 (+/- SEM) IU/L. The mean changes from baseline to week 12 in serum alkaline phosphatase were +0.5%, -24%, and -31%, respectively, for the three doses tested. The differences for each of the higher dose levels (0.25 and 0.5 mg/kg.day) was statistically significant (P < or = 0.05), and nearly half of the patients treated with the 0.5 mg/kg.day dose achieved a 50% or more reduction in enzyme activity. The nadir value in hydroxyproline excretion occurred at 10 weeks, with mean changes of +9%, -10%, and -17% for the 0.05, 0.25, and 0.5 mg/kg.day doses, respectively; the difference was significant only at the 0.5 mg/kg.day level (P < 0.01). Urinary collagen cross-link excretion showed a significant decrease at the 0.25 and 0.5 mg/kg.day doses. We also observed a definite, but nonsignificant, trend for improved quality of life in patients treated at the highest drug dose. Minor discomfort at the injection site was frequently reported, but did not lead to interruption of therapy. Our results in these patients who had received moderate to extensive prior therapies with other drugs show that cyclical, low dose, sc administration of gallium nitrate is safe and effective for treating patients with advanced Paget's disease of bone.


Asunto(s)
Galio/administración & dosificación , Osteítis Deformante/tratamiento farmacológico , Adulto , Anciano , Fosfatasa Alcalina/sangre , Resorción Ósea/prevención & control , Creatinina/orina , Relación Dosis-Respuesta a Droga , Femenino , Galio/efectos adversos , Galio/uso terapéutico , Humanos , Hidroxiprolina/orina , Masculino , Persona de Mediana Edad , Osteítis Deformante/fisiopatología , Péptidos/orina , Estudios Prospectivos , Calidad de Vida
8.
J Nucl Med ; 34(1): 61-70, 1993 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8418273

RESUMEN

This prospective, randomized multicenter study in 62 patients was designed to evaluate the efficacy and safety of radioimmunodetection (RAID) with 123I-labeled fragments, F(ab')2 and Fab', of IMMU-4, an anti-CEA monoclonal antibody (Immu-RAID-CEA). It was found that ImmuRAID-CEA was safe and disclosed colorectal cancer sites at least 1 cm in size. The positive predictive value by lesions was 77% initially, and increased to 91% after 7 mo of follow-up. Only one patient developed a low level of HAMA. In 17 patients with 32 surgically confirmed lesions, there were 9% true-positive lesions for CT when RAID was false-negative, and 22% for RAID when CT was false-negative. Either CT or RAID detected all 32 lesions. In this small series, therefore, RAID was shown to complement CT findings by confirming suspected tumors and disclosing new lesions which had previously been occult.


Asunto(s)
Antígeno Carcinoembrionario/inmunología , Neoplasias Colorrectales/diagnóstico por imagen , Radioisótopos de Yodo , Radioinmunodetección , Adulto , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Femenino , Humanos , Fragmentos de Inmunoglobulinas , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sensibilidad y Especificidad
9.
J Fla Med Assoc ; 79(1): 31-6, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1548455

RESUMEN

Thallium-201 myocardial perfusion scintigraphy assists in detecting coronary artery disease and assessing the significance of known stenoses. An adenosine infusion protocol is discussed in conjunction with presentation of results obtained in a community hospital setting. Primary indications for pharmacologic stress maneuvers include: Evaluation of patients unable or unwilling to exercise to adequate levels of workload and patients undergoing preoperative evaluation (particularly in patients undergoing vascular surgery). Experience in a community hospital setting attests to the safety of this pharmacologic protocol while showing a diagnostic accuracy similar to results reported in peer review literature. The method has been readily received by referring internists and cardiologists and is associated with a 21% increase in nuclear myocardial perfusion stress tests during the first six months of 1991.


Asunto(s)
Adenosina , Enfermedad Coronaria/diagnóstico por imagen , Radioisótopos de Talio , Corazón/diagnóstico por imagen , Humanos , Tomografía Computarizada de Emisión
10.
Clin Nucl Med ; 14(8): 580-7, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2805539

RESUMEN

Twenty-six stage II/III malignant melanoma patients with 321 measurable metastatic lesions were imaged using Fab fragments of an IgG murine monoclonal antibody labeled specifically with 10-30 mCi Tc-99m with a bi-functional chelating method (NeoRx, Seattle, WA). There were no side effects or adverse reactions. Immunoscintigraphy demonstrated 66.6% of lesions larger than 1 cm and 92.5% of lesions larger than 3 cm. Most frequently detected metastases were in lymph nodes, subcutaneous areas, and bone. Of lesions less than 1 cm, 23.6% were detected if superficial cutaneous lesions were excluded. The smallest detectable lesion was 4 mm. Twenty-one additional clinically unsuspected sites were visualized in 12 of the 26 patients studied. Of these, 56% were confirmed as metastasis by other tests. There were apparent nonspecific localizations owing to other causes, including fracture, varicosities, skin abscess and pneumonitis. Increased experience in image analysis facilitates correct interpretation of these localizations. This study demonstrates that imaging with Tc-99m labeled antibody fragments detects melanoma lesions in organs routinely surveyed and in other areas not routinely assessed by other imaging techniques. The procedure is readily performed and safe. The principal advantage of the test is its ability to survey the entire body and all organs with a single test. Its principal limitation, in common with other diagnostic imaging procedures, is its poor sensitivity for detecting lesions less than 1 cm.


Asunto(s)
Anticuerpos Monoclonales , Melanoma/secundario , Tecnecio , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Evaluación como Asunto , Femenino , Humanos , Masculino , Melanoma/diagnóstico por imagen , Persona de Mediana Edad , Metástasis de la Neoplasia , Cintigrafía
11.
Clin Nucl Med ; 9(9): 506-12, 1984 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-6091974

RESUMEN

Electrocardiographic gating provides an alternative method of acquiring first pass radionuclide ventriculograms from both ventricles. This report details the methods of acquisition and analysis, provides validation and reproducibility data, and describes applications of gated first pass radionuclide ventriculography using a count-based method. Left ventricular ejection fractions measured by gated first pass were correlated quite closely with gated blood pool ventriculography (n = 43; r = 0.95) but less well with contrast angiography (n = 23; r = 0.72). The right ventricular ejection fractions measured by gated first pass compared favorably with gated blood pool ventriculography (n = 32; r = 0.93). When one observer processed the images two times, the reproducibilities of RVEF (n = 10; r = 0.99) and LVEF (n = 10; r = 0.88) were excellent. Similarly, when two observers processed the images independently, the reproducibilities of RVEF (n = 11; r = 0.99) and LVEF (n = 11; r = 0.98) were excellent. The first pass studies were obtained in a right anterior obliquity, which provided the best atrioventricular chamber separation and provided a different view of global ventricular function and segmental wall motion from that provided by the standard blood pool views.


Asunto(s)
Cardiopatías/diagnóstico por imagen , Adolescente , Adulto , Anciano , Cardiomiopatías/diagnóstico por imagen , Femenino , Enfermedades de las Válvulas Cardíacas/diagnóstico por imagen , Humanos , Masculino , Métodos , Persona de Mediana Edad , Cintigrafía , Pertecnetato de Sodio Tc 99m , Volumen Sistólico
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