Risk Factors for Ebola Virus Persistence in Semen of Survivors in Liberia.

BACKGROUND: Long-term persistence of Ebola virus (EBOV) in immunologically privileged sites has been implicated in recent outbreaks of Ebola virus disease (EVD) in Guinea and the Democratic Republic of Congo. This study was designed to understand how the acute course of EVD, convalescence, and host immune and genetic factors may play a role in prolonged viral persistence in semen. METHODS: A cohort of 131 male EVD survivors in Liberia were enrolled in a case-case study. "Early clearers" were defined as those with 2 consecutive negative EBOV semen test results by real-time reverse-transcription polymerase chain reaction (rRT-PCR) ≥2 weeks apart within 1 year after discharge from the Ebola treatment unit or acute EVD. "Late clearers" had detectable EBOV RNA by rRT-PCR >1 year after discharge from the Ebola treatment unit or acute EVD. Retrospective histories of their EVD clinical course were collected by questionnaire, followed by complete physical examinations and blood work. RESULTS: Compared with early clearers, late clearers were older (median, 42.5 years; P < .001) and experienced fewer severe clinical symptoms (median 2, P = .006). Late clearers had more lens opacifications (odds ratio, 3.9 [95% confidence interval, 1.1-13.3]; P = .03), after accounting for age, higher total serum immunoglobulin G3 (IgG3) titers (P = .005), and increased expression of the HLA-C*03:04 allele (0.14 [.02-.70]; P = .007). CONCLUSIONS: Older age, decreased illness severity, elevated total serum IgG3 and HLA-C*03:04 allele expression may be risk factors for the persistence of EBOV in the semen of EVD survivors. EBOV persistence in semen may also be associated with its persistence in other immunologically protected sites, such as the eye.

Newborn Screening Practices for Beta-Thalassemia in the United States.

Beta-thalassemia, a heritable condition of abnormal hemoglobin production, is not a core condition on the United States Recommended Uniform Screening Panel (RUSP) for state and territorial newborn screening (NBS) programs. However, screening for sickle cell disease (which is on the core RUSP) also detects reduced or absent levels of hemoglobin (Hb) A and certain other Hb variants associated with beta-thalassemia and, thus, allows for a timely referral to appropriate healthcare to minimize sequalae of the disease. The Association of Public Health Laboratories' Hemoglobinopathy Workgroup administered a comprehensive survey of all U.S. NBS programs to assess beta-thalassemia testing methodologies, the cutoffs for defining beta-thalassemia major, and the reporting and follow-up practices. Forty-six (87%) of the programs responded. Thirty-nine of the 46 responding programs (85%) report some form of suspected beta-thalassemia; however, the screening methods, the percentage of Hb A used as a cutoff for an indication of beta-thalassemia major, and the screening follow-up vary widely. The standardization of technical and reporting procedures may improve access to specialty care prior to severe complications, increase genetic counseling, and provide data needed to better understand the public health impact and clinical outcomes of beta-thalassemia in the United States.

Laser trap ionization for identification of human erythrocytes with variable hemoglobin quantitation.

An approach to an established technique that is potentially applicable for a more comprehensive understanding of the electrical properties of red blood cells (RBCs) is presented. Using a high-intensity gradient laser trap, RBCs can be singly trapped and consequentially ionized. The subsequent dynamics of the ionized cell allows one to calculate the charge developed and the ionization energy (IE) through a Newtonian-based analysis. RBCs with two different hemoglobin (Hb) types were ionized. The first sample was identified as carrying Hb HbAA (normal Hb) and the second one was identified as carrying HbAC (HbC trait). By analyzing the charge developed on each cell and several other related factors, we were able to discern a difference between the main Hb types contained within the individual RBC, independent of cell size. A relationship between the charge developed and the IE of the cell was also established based on the electrical properties of RBCs. Thus, we present this laser trapping technique as a study of the electrical properties of RBCs and as possible biomedical tool to be used for the differentiation of Hb types.

Radiographically occult pulmonary metastases from gestational trophoblastic neoplasia.

Gestational trophoblastic neoplasia (GTN) is a spectrum of diseases including partial and complete hydatidiform moles, placental site trophoblastic tumor, and choriocarcinoma. One of the most important considerations is recognition of the possibility of GTN after molar pregnancy or even normal pregnancy. It is common practice to use chest x-ray for the detection of pulmonary metastasis. Computed tomography imaging of the lungs is ordered if lung lesions are noted on chest x-rays. However, understanding the limitations of chest x-rays is important for detecting smaller pulmonary lesions. We present a patient with GTN and pulmonary metastasis after having received 2 negative chest x-rays.

The Maternal Infant Health Outreach Worker program in low-income families.

Vanderbilt University Medical Center's Maternal Infant Health Outreach Worker program (MIHOW) is a community-based intervention dedicated to enhancing birth outcomes and healthy child development. Trained neighborhood women provide home and group services to underserved families in rural and inner city communities. This report describes MIHOW's history and work in Tennessee, Kentucky, West Virginia, Mississippi, and Louisiana.

Direct laser trapping for measuring the behavior of transfused erythrocytes in a sickle cell anemia patient.

Using a laser trap, we have studied the properties of erythrocytes from a sickle cell anemia patient (SCA) after receiving an intravenous blood transfusion, and a normal adult individual carrying normal adult hemoglobin. The hemoglobin type and quantitation assessment was carried out by high performance liquid chromatography (HPLC). We conducted an analysis of the size distributions of the cells. By targeting those erythrocytes in the overlapping regions of size distributions, we have investigated their properties when the cells are trapped and released. The efficacy of the transfusion treatment is also studied by comparing the relative changes in deformation and the relaxation-time of the cells in the two samples.

The relationship of oxygen transport and cardiac index for the prevention of sickle cell crises.

The formation of deoxyhemoglobin S (deoxy-Hb S) polymers is the key triggering event for the complex pathophysiologic manifestations of sickle cell anemia (SCA). This polymer formation is associated with a marked right-shifted oxyhemoglobin dissociation curve (decreased affinity, increased P50), which results in a decrease in arterial oxygen saturation (SaO2. There is a delay period ("delay time") from the formation of deoxy-Hb S to polymerization that is markedly sensitive (to the power of 30-40) to the concentration and solubility changes of deoxy-Hb S. Deoxy-Hb S polymer formation leads to sickle cell vaso-occlusion, a unique characteristic of SCA. This theoretical study, which views SCA as a disease of oxygen transport, provides a novel framework to suggest that a small to modest increase in cardiac index (by decreasing the P50 and thus increasing the SaO2) could change the distribution of the delay times (sec) such that the balance between occlusion and opening of microcirculatory vessels is shifted favoring the opening of these vessels, therefore disfavoring vaso-occlusion. Our approach integrates a mathematical model of oxygen transport in SCA with: (1) the expression relating the solubility of deoxy-Hb S to SaO2, and (2) the kinetic expression relating the delay time to the solubility of deoxy-Hb S.

Búsqueda de hemoglobinas anormales en los recién nacidos en las grandes alturas / Search of abnormal hemoglobin in new borns at high altitude

Se hizo un muestreo para detectar hemoglobinas anormales en recién nacidos (RN) de tres ciudades andinas situadas en el Perú: Cerro de Pasco, Huancayo y Puno. Estas ciudades están en altitudes que fluctuan entre los 3500 a 4400 m. sobre el nivel del mar. Objetivo: Investigar la presencia, de hemoglobinas anormales en RN nativos de altura. Material y métodos: Participaron un total de 234 RN. Se obtuvieron muestras de sangre del talón que fueron inmediatamente hemolizadas y refrigeradas para luego ser analizadas mediante electroforesis de punto isoeléctrico y cromatografía líquida de alto rendimiento. resultados: Los resultados indicaron que los RN tenían perfil de hemoglonina normal (HB A/F). Conclusiones: En estas muestras, que corresponden a una evaluación piloto, no se detectó ninguna variante anormal de hemoglobina, ni hemoglobinas de migración rápida (HB H, Hb Bart's).

Ultimos avances en el tratamiento de la enfermedad de células falciformes (sickle cell disease) / Latest treatment in sickle cell disease

La enfermedad de células falciformes (ECF) es definida como un grupo de desordenes genéticos caracterizados por la presencia de hemoglobina S (Hb S), anemia y daño tisular agudo y crónico. La anemia falciforme es el tipo más común de enfermedad de células falciformes, y es causada por la presencia del gen de blobina Bs en el estado hemocigoto. Por el momento no existe una cura para la anemia falciforme, con la excepción del transplante de médula ósea, que está disponible sólo para un número limitado de individuos. La falta de drogas o tratamientos para cura de la enfermedad de células falciformes es debida en parte a la ausencia de buenos modelos animales. Los modelos de ratones transgénicos para enfermedades falciformes brindan la oportunidad de experimentar con nuevos tratamientos, drogas y agentes anti-sickling para tratar estas enfermedades. Hasta que una cura sea hallada, el tratamiento continuará siendo para las complicaciones asociadas con la enfermedad. Ultimos avances sobre inmunizaciones, penicilina profiláctica, ácido fólico, trental, quelación y terapia de hierro, experimental y otras drogas para el tratamiento de la anemia falciforme son presentados en este artículo.