RESUMEN
Objective. Bioimpedance spectroscopy (BIS) is a popular technique for the assessment of body composition in children and adults but has not found extensive use in babies and infants. This due primarily to technical difficulties of measurement in these groups. Although improvements in data modelling have, in part, mitigated this issue, the problem continues to yield unacceptably high rates of poor quality data. This study investigated an alternative data modelling procedure obviating issues associated with BIS measurements in babies and infants.Approach.BIS data are conventionally analysed according to the Cole model describing the impedance response of body tissues to an appliedACcurrent. This approach is susceptible to errors due to capacitive leakage errors of measurement at high frequency. The alternative is to model BIS data based on the resistance-frequency spectrum rather than the reactance-resistance Cole model thereby avoiding capacitive error impacts upon reactance measurements.Main results.The resistance-frequency approach allowed analysis of 100% of data files obtained from BIS measurements in 72 babies compared to 87% successful analyses with the Cole model. Resistance-frequency modelling error (percentage standard error of the estimate) was half that of the Cole method. Estimated resistances at zero and infinite frequency were used to predict body composition. Resistance-based prediction of fat-free mass (FFM) exhibited a 30% improvement in the two-standard deviation limits of agreement with reference FFM measured by air displacement plethysmography when compared to Cole model-based predictions.Significance.This study has demonstrated improvement in the analysis of BIS data based on the resistance frequency response rather than conventional Cole modelling. This approach is recommended for use where BIS data are compromised by high frequency capacitive leakage errors such as those obtained in babies and infants.
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Composición Corporal , Espectroscopía Dieléctrica , Impedancia Eléctrica , Humanos , Lactante , Espectroscopía Dieléctrica/métodos , Recién Nacido , Masculino , FemeninoRESUMEN
The Cuban Human Brain Mapping Project (CHBMP) repository is an open multimodal neuroimaging and cognitive dataset from 282 young and middle age healthy participants (31.9 ± 9.3 years, age range 18-68 years). This dataset was acquired from 2004 to 2008 as a subset of a larger stratified random sample of 2,019 participants from La Lisa municipality in La Habana, Cuba. The exclusion criteria included the presence of disease or brain dysfunctions. Participant data that is being shared comprises i) high-density (64-120 channels) resting-state electroencephalograms (EEG), ii) magnetic resonance images (MRI), iii) psychological tests (MMSE, WAIS-III, computerized go-no go reaction time), as well as iv,) demographic information (age, gender, education, ethnicity, handedness, and weight). The EEG data contains recordings with at least 30 minutes in duration including the following conditions: eyes closed, eyes open, hyperventilation, and subsequent recovery. The MRI consists of anatomical T1 as well as diffusion-weighted (DWI) images acquired on a 1.5 Tesla system. The dataset presented here is hosted by Synapse.org and available at https://chbmp-open.loris.ca .
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Mapeo Encefálico , Cognición , Electroencefalografía , Imagen por Resonancia Magnética , Adolescente , Adulto , Anciano , Cuba , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Adulto JovenRESUMEN
This study reports on the drug resistance profiles for HIV-infected pediatrics in Jamaica who have been exposed to antiretroviral therapy (ART). The genetic diversity of HIV-1 found in these patients was also determined using phylogenetic analysis. The protease-reverse transcriptase (Pro-RT) region of the genome was amplified from 40 samples, sequenced, and analyzed for the identification of antiretroviral resistance-associated mutations (RAMs). All isolates belonged to subtype B and 39 possessed multiple RAMs in the reverse transcriptase genes that would compromise the efficacy of drugs being used to treat these patients. Four isolates possessed RAMs in the protease genes. The overall frequency of HIV drug resistance was 95%. The high frequency of drug resistance is supported by epidemiological data that revealed an equally high frequency of treatment failure (98%) among the study participants. The results of this study indicate the urgent need for greater access to drug resistance testing in Jamaica.
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Farmacorresistencia Viral , Genes pol , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Transcriptasa Inversa del VIH/genética , VIH-1/genética , Fármacos Anti-VIH/uso terapéutico , Niño , Preescolar , Variación Genética , VIH-1/efectos de los fármacos , Humanos , Lactante , Recién Nacido , Jamaica , Datos de Secuencia Molecular , Mutación , Filogenia , Análisis de Secuencia de ADN , Insuficiencia del TratamientoRESUMEN
UNLABELLED: BACKGROUND AND RATIONALE FOR THE STUDY: The Model for End Stage Liver Disease (MELD) score has not been derived and validated for the emergent transjugular intrahepatic portosystemic shunt (TIPS) population. We sought to identify predictive factors for survival among emergent TIPS patients, and to substantiate MELD for outcomes prognostication in this population. RESULTS: 101 patients with acute life threatening variceal hemorrhage underwent emergent TIPS (defined by failed endoscopic therapy for active bleeding, acute hemoglobin drop, ≥ 2-unit transfusion requirement, and/or vasopressor need) at between 1998-2013. Demographic, clinical, laboratory, and procedure parameters were analyzed for correlation with mortality using Cox proportional hazards regression to derive the prognostic value of MELD constituents. Area under receiver operator characteristic (AUROC) curves was used to assess the capability of MELD prediction of mortality. TIPS were created 119 ± 167 h after initial bleeding events. Hemodynamic success was achieved in 90%. Median final portosystemic pressure gradient was 8 mmHg. Variceal rebleeding incidence was 21%. The four original MELD components showed significant correlation with mortality on multivariate Cox regression: baseline bilirubin (regression coefficient 0.366), creatinine (0.621), international normalized ratio (1.111), and liver disease etiology (0.808), validating the MELD system for emergent cases. No other significant predictive parameters were identified. MELD was an excellent predictor of 90-day mortality in the emergent TIPS population (AUROC = 0.842, 95% CI 0.755-0.928). CONCLUSIONS: Based on independent derivation of prognostic constituents and confirmation of predictive accuracy, MELD is a valid and reliable metric for risk stratification and survival projection after emergent TIPS.
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Urgencias Médicas , Enfermedad Hepática en Estado Terminal/mortalidad , Várices Esofágicas y Gástricas/cirugía , Hemorragia Gastrointestinal/cirugía , Derivación Portosistémica Intrahepática Transyugular , Enfermedad Aguda , Enfermedad Hepática en Estado Terminal/complicaciones , Várices Esofágicas y Gástricas/complicaciones , Femenino , Estudios de Seguimiento , Hemorragia Gastrointestinal/etiología , Humanos , Illinois/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia/tendenciasRESUMEN
This study reports on the drug resistance profiles for HIV-infected adults in Jamaica using genotypic methods. The genetic diversity of HIV-1 found in these patients was also determined using phylogenetic analysis. Epidemiological data were documented for each patient, blood was collected by venous puncture, and plasma was separated and stored. Viral RNA was extracted and analyzed for mutations in the viral genome by the amplification of the protease and reverse transcriptase (Pro-RT) regions using a nested PCR method. The rate of drug resistance among treatment-experienced individuals was 35%, while treatment-naive individuals showed a prevalence of 29%. The overall prevalence of drug resistance mutations in Jamaicans was consistent with the increased use of antiretroviral drugs in the region, with many of the mutations detected reducing susceptibility to the drugs commonly used to treat Jamaican patients. These results indicate the need for regular drug resistant surveillance to guide treatment strategies.