Effects of TGFbeta2 on collagen synthesis in cultured normal and wounded fetal mouse palates.

OBJECTIVE: It has been demonstrated in a number of models that fetal wounds heal with little or no scar. Since collagen is an integral part of the extracellular matrix in adult scar formation, we studied the synthesis and localization of collagen in an in vitro mouse palate model for fetal wound healing. METHODS: Palates, dissected from fetal mice at 15, 16, and 17 days of gestation and from newborn mice, were cultured in medium containing serum (for 8 hours); this was followed by culture in serum-free medium (for 12 hours). One-half of the samples from each age group were wounded in the midline. All samples were placed in serum-free medium containing 20 microCi/mL 3H-proline for 8 hours. In addition, palates from 15-day gestation and from newborn mice were also incubated with transforming growth factor TGF-beta2 (10 ng/mL). Palates were washed with saline, homogenized, and radioactivity was counted. Proline uptake was calculated for each sample as counts per milligram of protein and was subjected to statistical analysis (three-way analysis of variance). Samples of the homogenate were subjected to sodium dodecyl sulfate-gel electrophoresis and Western blotting in order to determine the types of collagen that were synthesized. Immunohistochemical localization of collagen types I, III, and VI was carried out on paraffin-embedded samples from each group. RESULTS: There were no significant differences in proline uptake between wounded mouse palates and nonwounded mouse palates at any age, and there was no histological evidence of regeneration of the palate at the site of the wound. Proline uptake was significantly greater in untreated wounded palates at 15 days' gestation than it was in newborns. After treatment with TGF-beta2, proline uptake was significantly greater in both wounded and nonwounded palates in the newborn group and had no effect on collagen synthesis in palates from 15-day gestation animals. Collagen types I and III were localized in histological specimens using immunohistochemistry and on nitrocellulose using Western blotting. No type VI collagen was demonstrated by Western blotting, but it was localized around blood vessels and on basement membranes using immunohistochemistry. CONCLUSION: Treatment with TGF-beta2 significantly increased collagen synthesis, as assessed by 3H-proline uptake, in cultured palates from newborn mice as compared with palates from untreated newborn mice and from both treated and untreated palates of 15-day gestation mice. These data suggest a differential response to TGF-beta2 by mouse palates as a function of fetal development.     

Hepatitis B Virus Reactivation: Risk Factors and Current Management Strategies

Hepatitis B virus (HBV) is a global disease with significant morbidity and mortality. Worldwide, ~257 million people are chronically infected with HBV, defined as having a positive hepatitis B surface antigen, but millions more have prior HBV exposure indicated by positive hepatitis B core antibody. Reactivation of hepatitis B implies a sudden increase in viral replication in a patient with chronic HBV infection or prior HBV exposure. Hepatitis B virus reactivation (HBVr) can occur spontaneously, but it is more commonly triggered by immunosuppressive therapies for cancer, immunologic diseases, or transplantation. Elimination of hepatitis C virus (HCV) in HBV-HCV coinfected individuals treated with direct-acting antivirals (DAAs) has also been identified as an important cause of HBVr. Hepatitis B virus reactivation is an underappreciated but important complication of common medical therapies that can delay treatment or result in clinical episodes of hepatitis, hepatic failure, or death. In this review, factors associated with HBVr, particularly medication-related risks, are explored. We review data involving rituximab and ofatumumab, doxorubicin, corticosteroids, tumor necrosis factor antagonists, tyrosine kinases, bortezomib, hematologic stem cell transplantation, and DAAs for HCV treatment. In addition, we discuss screening strategies, choice of antiviral prophylaxis, and the optimal duration of therapy for HBVr. With additional awareness, screening, and appropriate antiviral therapy, it is expected that most cases of HBVr can be prevented.     

Practice‐based Research Network Research Good Practices (PRGPs): Summary of Recommendations

Introduction

Practice‐based research networks (PBRNs) conduct research in community settings, which poses quality control challenges to the integrity of research, such as study implementation and data collection. A foundation for improving research processes within PBRNs is needed to ensure research integrity.

Methods

Network directors and coordinators from seven U.S.‐based PBRNs worked with a professional team facilitator during semiannual in‐person meetings and monthly conference calls to produce content for a compendium of recommended research practices specific to the context of PBRNs. Participants were assigned to contribute content congruent with their expertise. Feedback on the draft document was obtained from attendees at the preconference workshop at the annual PBRN meeting in 2013. A revised document was circulated to additional PBRN peers prior to finalization.

Results

The PBRN Research Good Practices (PRGPs) document is organized into four chapters: (1) Building PBRN Infrastructure; (2) Study Development and Implementation; (3) Data Management, and (4) Dissemination Policies. Each chapter contains an introduction, detailed procedures for each section, and example resources with information links.

Conclusion

The PRGPs is a PBRN‐specific resource to facilitate PBRN management and staff training, to promote adherence to study protocols, and to increase validity and generalizability of study findings.     

Development of a Model for Evaluating the Interaction Between Human Pre-B Acute Lymphoblastic Leukemic Cells and the Bone Marrow Stromal Cell Microenvironment

Clonal expansion of B-cell precursor acute lymphoblastic leukemia(ALL) is potentially regulated by survival, growth, and death signalstransduced by the bone marrow (BM) microenvironment. Using a human BMstromal cell culture that supports the growth of normal human B-cellprecursors, we established a pre-B ALL cell line designated BLIN-2.BLIN-2 has a clonal rearrangement of the Ig heavy chain locus, adic(9;20) chromosomal abnormality, and a bi-allelic deletion of thep16^INK4a and p19^ARF genes. Themost interesting feature of BLIN-2 is an absolute dependence onadherent human BM stromal cells for sustained survival and growth.BLIN-2 cultured in the absence of BM stromal cells undergo apoptosis,and direct contact with viable BM stromal cells is essential foroptimal growth. BLIN-2 cells also grow on vascular cell adhesionmolecule-1 (VCAM-1)-negative human skin fibroblasts, making itunlikely that a very late antigen-4 (VLA-4)/VCAM-1interaction is required for BLIN-2 growth. Western blot analysis ofBLIN-2 cells cultured in the presence or absence of BM stromal cells demonstrates that contact of BLIN-2 with BM stromal cells induces hyperphosphorylation of Rb. In contrast, the pre-B ALL cell line BLIN-1, which has a bi-allelic deletion of p16^INK4ap19^ARF but does not require BM stromal cells for growth,does not undergo Rb phosphorylation after BM stromal cell contact. TheBLIN-2 cell line will facilitate identification of ligand/receptorinteractions at the B-cell precursor/BM stromal cell interface and mayprovide new insight into microenvironmental regulation of leukemic cell survival and growth.     

Human Coinfection with Bartonella henselae and Two Hemotropic Mycoplasma Variants Resembling Mycoplasma ovis

Two variants of an organism resembling the ovine hemoplasma, Mycoplasma ovis, were detected by PCR in blood samples from a veterinarian in Texas. Coinfection with similar variants has been described in sheep. This represents the first report of human infection with this organism. The veterinarian was coinfected with Bartonella henselae.     

Community trends in the early detection of breast cancer in Wisconsin, 1980-1998

BACKGROUND: Early detection of breast cancer is an important public health goal. Rates of early detection have increased over the past several decades, contributing to recent declines in mortality. Despite these overall trends, however, some populations have experienced less progress than others. METHODS: The rates of early detection, measured as the percentage of breast cancers diagnosed as breast carcinoma in situ, were calculated using data from Wisconsin's population-based tumor registry from 1980 to 1998. Trends in breast cancer (percent diagnosed in situ) were examined over time by socioeconomic characteristics of ZIP code of residence, using census data. RESULTS: The percentage of breast cancer cases that were breast carcinoma in situ was more than five times greater in the later period (1994-1998) (13.9%), compared with the early period (1980-1984) (2.6%). In the middle period (1987-1991), breast cancer was diagnosed as breast carcinoma in situ about one-third less frequently among women in areas with the lowest urbanization, median family income, and percent educated beyond high school, compared with communities with the highest levels of these variables. Recently disparities in early detection rates by community income and education indicators declined slightly, whereas disparities in percent of breast carcinoma in situ by urbanization did not. CONCLUSIONS: Communities with lower levels of income, education, and urbanization lagged in the early detection of breast cancer during the 1980s and, despite some progress during the 1990s, continue to be underserved. Women in these communities should be targeted for interventions to improve the early detection of breast cancer.     

Outcomes in sinonasal mucosal melanoma

BACKGROUND: The present paper assesses treatment outcomes in a series of 20 patients with sinonasal mucosal melanoma (SNMM) over 11 years. METHODS: All patients who presented to a single institution between 1991 and 2002 with a diagnosis of SNMM had their treatment reviewed and outcomes determined. RESULTS: Twenty patients presented to our institution with SNMM over the study period. No cervical node or metastatic involvement was detected at presentation. The most common site of involvement was the nasal cavity (17/20). The majority of patients received initial surgery followed by radiotherapy (15/20). At the completion of treatment 14 patients had no disease evident. The median time to failure in these patients was 12 months. Of these patients 10 relapsed, including six who had metastatic failure only. Fifteen patients died due to disease. Median overall survival was 17 months, with a 2-year overall survival of 23%. In univariate analysis, patients with advanced tumours (T3-4) had a 4.3 times greater risk of dying than patients with early tumours (T1-2). CONCLUSIONS: Patients with SNMM have poor outcomes with conventional therapy. Full staging prior to treatment is recommended. Aggressive treatment carrying significant morbidity is justified only for patients with early stage disease.