Publications by authors named "LT Brown"

The properties of native spider silk vary within and across species due to the presence of different genes containing conserved repetitive core domains encoding a variety of silk proteins. Previous studies seeking to understand the function and material properties of these domains focused primarily on the analysis of dragline silk proteins, MaSp1 and MaSp2. Our work seeks to broaden the mechanical properties of silk-based biomaterials by establishing two libraries containing genes from the repetitive core region of the native silk genome (Library A: genes , , , ; Library B: genes , , , ).

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Chlamydia trachomatis infection (chlamydia) is the most prevalent sexually transmitted bacterial infection and causes significant reproductive morbidity in women. Little is known about how immunity to chlamydia develops in women, though animal models of chlamydia indicate that T-helper type 1 (Th1) responses are important for chlamydia clearance and protective immunity, whereas T-helper type 2 (Th2) responses are associated with persisting infection. In chlamydia-infected women, whether the predominant immune response is Th1- or Th2-polarizing remains controversial.

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T cell phenotypes involved in the immune response to Chlamydia trachomatis (CT) have not been fully elucidated in humans. We evaluated differences in T cell phenotypes between CT-infected women and CT-seronegative controls and investigated changes in T cell phenotype distributions after CT treatment and their association with reinfection. We found a higher expression of T cell activation markers (CD38HLA-DR), T helper type 1 (Th1)- and Th2-associated effector phenotypes (CXCR3CCR5 and CCR4, respectively), and T cell homing marker (CCR7) for both CD4 and CD8 T cells in CT-infected women.

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Chlamydiatrachomatis (Ct) infection causes significant morbidity. In vitro studies demonstrate that Ct growth inhibition occurs by interferon-gamma (IFN-γ)-mediated depletion of intracellular tryptophan, and some Ct strains utilize extracellular indole to restore tryptophan levels. Whether tryptophan levels are associated with Ct infection clearance in humans remains unknown.

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Chlamydia trachomatis elementary body enzyme-linked immunosorbent assay (ELISA) was used to investigate serum anti-CT immunoglobulin G1 (IgG1; long-lived response) and immunoglobulin G3 (IgG3; short-lived response indicating more recent infection) from treatment (enrollment) and 6-month follow-up visits in 77 women previously classified as having spontaneous resolution of chlamydia. Of these women, 71.4% were IgG1+IgG3+, consistent with more recent chlamydia resolution.

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Ommaya reservoirs are an important surgical therapy for the chronic intrathecal administration of chemotherapy for patients with leptomeningeal carcinomatosis. Surgical accuracy is paramount in these patients with typically normal sized ventricles, and may be improved with stereotactic guidance. This paper aimed to review a large series of stereotactic Ommaya catheter placements, examining accuracy and complications.

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Background: Ommaya reservoirs are ventricular access devices used primarily for the administration of intrathecal antineoplastic chemotherapy. In patients with low or normal ventricular volume, stereotaxy can improve accuracy of catheter placement with minimal morbidity. Frameless stereotaxy has become an increasingly popular alternative to frame-based stereotaxy.

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Elongating DNA polymerases frequently encounter lesions or structures that impede progress and require repair before DNA replication can be completed. Therefore, directing repair factors to a blocked fork, without interfering with normal replication, is important for proper cell function, and it is a process that is not well understood. To study this process, we have employed the chain-terminating nucleoside analog, 3' azidothymidine (AZT) and the E.

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OBJECT The object of this study was to perform a systematic review, according to Preferred Reporting Items of Systematic reviews and Meta-Analyses (PRISMA) and Agency for Healthcare Research and Quality (AHRQ) guidelines, of the clinical efficacy and adverse effect profile of dorsal anterior cingulotomy compared with anterior capsulotomy for the treatment of severe, refractory obsessive-compulsive disorder (OCD). METHODS The authors included studies comparing objective clinical measures before and after cingulotomy or capsulotomy (surgical and radiosurgical) in patients with OCD. Only papers reporting the most current follow-up data for each group of investigators were included.

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Importance: African American individuals experience barriers to accessing many types of health care in the United States, resulting in substantial health care disparities. To improve health care in this patient population, it is important to recognize and study the potential factors limiting access to care.

Objective: To examine deep brain stimulation (DBS) use in Parkinson disease (PD) to determine which factors, among a variety of demographic, clinical, and socioeconomic variables, drive DBS use in the United States.

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Objective: To review the efficacy and safety of risperidone for augmentation treatment in patients with major depressive disorder who fail to achieve adequate response to antidepressant monotherapy.

Data Sources: A search of MEDLINE (1966-August 2010) and EMBASE (1980-August 2010) was conducted, using the terms risperidone and major depressive disorder. In addition, a manual search of the references cited in each publication identified from the database search was conducted to identify relevant articles.

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The Institute of Medicine report, Unequal Treatment, asserts that conscious and unconscious bias of providers may affect treatments delivered and contribute to health disparities. The primary study objective is to measure, compare, and contrast objective and subjective cognitive processes among pharmacy, nursing, and medical students to discern potential implications for health disparities. Data were collected using a cultural competency questionnaire and two implicit association tests (IATs).

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Parkinson's disease is caused by a progressive loss of the midbrain dopamine (DA) neurons in the substantia nigra pars compacta. Although the main cause of Parkinson's disease remains unknown, there is increasing evidence that it is a complex disorder caused by a combination of genetic and environmental factors, which affect key signalling pathways in substantia nigra DA neurons. Insights into pathogenesis of Parkinson's disease stem from in vitro and in vivo models and from postmortem analyses.

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The stem-cement interface has long been implicated in failure of cemented total hip replacement. Much research has been performed to study the factors affecting the bond strength between the femoral stem and the bone cement. The present study aims to further investigate the influence of femoral stem surface finish on the apparent static shear strength at the stem-cement interface through a series of pull out tests, where stainless steel rods are employed to represent the femoral stem.

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The toxicity of copper [Cu(II)] to sulfate-reducing bacteria (SRB) was studied by using Desulfovibrio desulfuricans G20 in a medium (MTM) developed specifically to test metal toxicity to SRB (R. K. Sani, G.

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Germline mutations of the TP53 tumor suppressor gene account for the predisposition to cancer observed in many Li-Fraumeni syndrome (LFS) families. A causative genetic factor in the remaining families that harbor no TP53 mutations remains to be elucidated. The PTEN phosphatase tumor suppressor gene is mutated in human cancers observed in LFS.

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This article is an epidemiological analysis of Baltimore homicides between 1986 and 1990. The main findings were that young African-American males between 15 and 34 years of age are at greatest risk of homicide victimization. Homicidal events primarily occurred with handguns, in drug-related circumstances, between acquaintances, and in the western police district area.

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Three popular videotapes were assessed for their effectiveness in improving knowledge and attitudes about acquired immune deficiency syndrome (AIDS). One hundred forty-four university students completed knowledge and attitude questionnaires and then watched either an AIDS or a control tape. Half the students completed posttest questionnaires immediately after seeing the tape, and half were tested 1 month later.

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Continuous pulse oximetry monitoring was used to determine the incidence of hypoxaemia (arterial oxygen saturation less than or equal to 90%) occurring in the first hour of postoperative recovery. Of 107 patients studied, hypoxaemia was recorded in 80%. Twenty-eight (26%) of these patients had saturations below 80%.

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Methods have been developed for the simultaneous quantitative analysis of vitamin B6 forms in biological samples by isotope dilution mass spectrometry using deuterated forms of pyridoxine, pyridoxal, pyridoxamine, and pyridoxic acid. The biological fluid or tissue sample was homogenized and then treated with a cocktail containing appropriate amounts of each deuterated vitamer, as well as the deuterated, phosphorylated vitamer forms. The individual vitamers were isolated from the homogenate by a complex high-performance liquid chromatographic procedure that provided separate fractions for each of the six vitamers found in biological samples.

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