University of Texas Medical Branch

About: University of Texas Medical Branch is a education organization based out in Galveston, Texas, United States. It is known for research contribution in the topics: Population & Virus. The organization has 22033 authors who have published 38268 publications receiving 1517502 citations. The organization is also known as: The University of Texas Medical Branch at Galveston & UTMB.

Massive Brain Hemorrhage: A Review of 144 Cases and an Examination of Their Causes

Abstract: A detailed clinicopathological study of the causes and locations of massive nontraumatic brain hemorrhage in 144 patients is reported. A cause of the hemorrhage, such as an aneurysm, angioma, arteritis, neoplasm or a blood dyscrasia (leukemia, hemophilia), was proved in two-thirds (95) of these patients. Twelve normotensive patients had no cause found to explain their hemorrhage. Systemic hypertension, generally mild, defined as a pre-ictal pressure of > 140/90 or by excessive heart weight, was present in 58 of the 144 patients. Twenty-one of these 58 hypertensive patients had a clear discernible cause for their brain hemorrhage (i.e., leukemia, metastatic carcinoma, angioma, aneurysm), whereas no satisfactory morphological cause could be found in only 37. Thus, in only about one-fourth of our patients could any serious claim be made that hypertension was the cause of the hemorrhage. Our data would indicate the need for a critical study of the causes of intracranial hemorrhages, and re-evaluation of the t...

Large number of rebounding/founder HIV variants emerge from multifocal infection in lymphatic tissues after treatment interruption

Abstract: Antiretroviral therapy (ART) suppresses HIV replication in most individuals but cannot eradicate latently infected cells established before ART was initiated. Thus, infection rebounds when treatment is interrupted by reactivation of virus production from this reservoir. Currently, one or a few latently infected resting memory CD4 T cells are thought be the principal source of recrudescent infection, but this estimate is based on peripheral blood rather than lymphoid tissues (LTs), the principal sites of virus production and persistence before initiating ART. We, therefore, examined lymph node (LN) and gut-associated lymphoid tissue (GALT) biopsies from fully suppressed subjects, interrupted therapy, monitored plasma viral load (pVL), and repeated biopsies on 12 individuals as soon as pVL became detectable. Isolated HIV RNA-positive (vRNA+) cells were detected by in situ hybridization in LTs obtained before interruption in several patients. After interruption, multiple foci of vRNA+ cells were detected in 6 of 12 individuals as soon as pVL was measureable and in some subjects, in more than one anatomic site. Minimal estimates of the number of rebounding/founder (R/F) variants were determined by single-gene amplification and sequencing of viral RNA or DNA from peripheral blood mononuclear cells and plasma obtained at or just before viral recrudescence. Sequence analysis revealed a large number of R/F viruses representing recrudescent viremia from multiple sources. Together, these findings are consistent with the origins of recrudescent infection by reactivation from many latently infected cells at multiple sites. The inferred large pool of cells and sites to rekindle recrudescent infection highlights the challenges in eradicating HIV.

Emerging and re-emerging rickettsioses: endothelial cell infection and early disease events

Abstract: Rickettsiae cause some of the most severe human infections, including epidemic typhus and Rocky Mountain spotted fever Substantial progress has been made in research into the genomics, vector relationships, pathogenesis and immunity of these obligate, intracellular, arthropod-transmitted bacteria This Review summarizes our understanding of the early and late events in pathogenesis and immunity, modulation of the host response to rickettsial infection by the vector, host defence, virulence mechanisms and rickettsial manipulation of host cells

Production of stem cells with embryonic characteristics from human umbilical cord blood

Abstract: When will embryonic stem cells reach the clinic? The answer is simple -- not soon! To produce large quantities of homogeneous tissue for transplantation, without feeder layers, and with the appropriate recipient's immunological phenotype, is a significant scientific hindrance, although adult stem (ADS) cells provide an alternative, more ethically acceptable, source. The annual global 100 million human birth rate proposes umbilical cord blood (UCB) as the largest untouched stem cell source, with advantages of naive immune status and relatively unshortened telomere length. Here, we report the world's first reproducible production of cells expressing embryonic stem cell markers, - cord-blood-derived embryonic-like stem cells (CBEs). UCB, after elective birth by Caesarean section, has been separated by sequential immunomagnetic removal of nucleate granulocytes, erythrocytes and haemopoietic myeloid/lymphoid progenitors. After 7 days of high density culture in microflasks, (10(5) cells/ml, IMDM, FCS 10%, thrombopoietin 10 ng/ml, flt3-ligand 50 ng/ml, c-kit ligand 20 ng/ml). CBE colonies formed adherent to the substrata; these were maintained for 6 weeks, then were subcultured and continued for a minimum 13 weeks. CBEs were positive for TRA-1-60, TRA-1-81, SSEA-4, SSEA-3 and Oct-4, but not SSEA-1, indicative of restriction in the human stem cell compartment. The CBEs were also microgravity--bioreactor cultured with hepatocyte growth medium (IMDM, FCS 10%, HGF 20 ng/ml, bFGF 10 ng/ml, EGF 10 ng/ml, c-kit ligand 10 ng/ml). After 4 weeks the cells were found to express characteristic hepatic markers, cytokeratin-18, alpha-foetoprotein and albumin. Thus, such CBEs are a viable human alternative from embryonic stem cells for stem cell research, without ethical constraint and with potential for clinical applications.