Stress and coping in African American grandparents who are raising grandchildren

Over the years, substantial increases have occurred in the number of children being raised by their grandparents. A small number of studies have reported that grandparents raising grandchildren experience an increase in stress due to the demands of caregiving. The primary objectives of this study were to: (1) determine the degree of stress in African American (AA) grandparents who are raising their grandchildren age 12 years or younger; (2) identify the variables pertaining to the demographic characteristics of the grandparent caregiver and characteristics of the caregiving situation; (3) identify the coping strategies reported by AA grandparents; and (4) identify the relative importance of demographic and situational variables pertaining to the grandparent caregiver and caregiving situation, and coping strategies in influencing the degree of stress experienced. ^ An exploratory, descriptive, cross sectional design was used to study stress and coping in 50 AA grandparents who ranged in age from 44–87 years (M = 63.12). Data were collected via one personal interview in January/February 2001 at area senior centers or churches which the grandparent attends in Harris County, Texas. Five home interviews were done as requested by grandparents. ^ The instruments used to measure stress and coping were the Parenting Stress Index developed by Abidin and Folkman and Lazarus' Ways of Coping Questionnaire. Results of the study found that the grandparents is this study were a highly stressed group. Ninety-four percent of the sample demonstrated a “clinically significant” level of stress. Situational variables associated with lower stress levels were use of counseling, use of special school programs such as tutoring and special education, and increased length of caregiving (>5 years). ^ The most frequently used coping strategies overall were seeking social support and positive reappraisal. Six coping strategies were significantly correlated to lower reported stress: positive reappraisal, accepting responsibility, confrontive coping, self-control, planful problem solving, and distancing. ^ The findings from this study have limited generalizability. Nonetheless, this study was useful in adding to the limited amount of literature on AA grandparents who are rearing their grandchildren. The results clearly suggest the need for affordable counseling, support groups, education related to available resources, stress management, and interventions that increase the use of coping strategies found to reduce perceived stress. Future research should investigate levels of stress in AA and other grandparent caregivers longitudinally, as well as focus on stress and coping in grandparents raising grandchildren with special needs. ^

Factors Associated with Early Versus Late Development of Breast and Ovarian Cancer in BRCA1 and BRCA2 Positive Women

Hereditary breast and ovarian cancer (HBOC) is caused by a mutation in the BRCA1 or BRCA2 genes. Women with a BRCA1/2 mutation are at increased risks for breast and ovarian cancer and often develop cancer at an earlier age than the general population. However, some women with a BRCA1/2 mutation do not develop breast or ovarian cancer under the age of 50 years. There have been no specific studies on BRCA positive women with no cancer prior to age 50, therefore this study sought to investigate factors within these women with no cancer under age 50 with respect to reproductive risk factors, BMI, tumor pathology, screening history, risk-reducing surgeries, and family history. 241 women were diagnosed with cancer prior to age 50, 92 with cancer at age 50 or older, and 20 women were over age 50 with no cancer. Data were stratified based on BRCA1 and BRCA2 mutation status. Within the cohorts we investigated differences between women who developed cancer prior to age 50 and those who developed cancer at age 50 or older. We also investigated the differences between women who developed cancer at age 50 or older and those who were age 50 or older with no cancer. Of the 92 women with a BRCA1/2 mutation who developed cancer at age 50 or older, 46 developed ovarian cancer first, 45 developed breast cancer, and one had breast and ovarian cancer diagnosed synchronously. BRCA2 carriers diagnosed age 50 or older were more likely to have ER/PR negative breast tumors when compared to BRCA2 carriers who were diagnosed before age 50. This is consistent with one other study that has been performed. Ashkenazi Jewish women with a BRCA1 mutation were more likely to be diagnosed age 50 or older than other ethnicities. Hispanic women with a BRCA2 mutation were more likely to be diagnosed prior to age 50 when compared to other ethnicities. No differences in reproductive factors or BMI were observed. Further characterization of BRCA positive women with no cancer prior to age 50 may aid in finding factors important in the development of breast or ovarian cancer.

A RANDOMIZED TRIAL OF BILEVEL POSITIVE AIRWAY PRESSURE DEVICE AND HIGH FLOW OXYGEN FOR PERSISTENT DYSPNEA IN

Background: Dyspnea is a common and distressing symptom among patients with advanced cancer. The role of bilevel positive airway pressure (BIPAP) and Vapotherm in the relief of dyspnea have not been well defined. We aimed to determine and to compare the efficacy of BIPAP and VapoTherm for cancer related dyspnea. Methods: In this randomized, open-label, crossover study, we randomly assigned advanced cancer patients with persistent dyspnea >=3/10 to either Vapotherm for 2 hours followed by BiPAP for 2 hours, or BiPAP followed by Vaptherm. A variable washout period was instituted between interventions. The primary end point was change in numeric rating scale before and after each intervention. We planned to enroll 50 patients in total. Results: Among the 803 patients screened over the last 8 months, 62 (26%) were eligible, and 16 (2%) were enrolled so far. Five patients completed the entire study successfully, 4 discontinued the study prematurely due to prolonged relief of dyspnea, and 7 dropped out for various reasons, including inability to tolerate BiPAP (N=3), anxiety (N=2), fatigue (N=1) and pain requiring opioids (N=1). The median baseline numeric rating score for dyspnea was 7/10 (interquartile range (IQR) 5-8), and the median baseline Borg score was 4/10 (3-7). Interim analysis revealed that BiPAP was associated with a median change in numeric rating score of -3 (N=10, IQR -6.3 to -1, p=0.007) and modified Borg score of -1 (N=10, IQR -3 to 0.3, p=0.058), while Vapotherm was associated with a median change in numeric rating score of -2 (N=9, IQR -3 to -1, p=0.011) and modified Borg score of -2.5 (N=8, IQR -5.5 to -0.1, p=0.051). Among the 5 individuals who completed the entire study, 2 preferred Vapotherm, 2 favored BiPAP, and 1 liked both. The respiratory rate decreased and the oxygen saturation improved with both interventions. No significant toxicities were observed. Conclusions: We were successfully able to enroll patients onto this clinic trial. Our preliminary results suggest that BiPAP and Vapotherm are highly efficacious in providing relief for patients with persistent refractory dyspnea. A direct comparison of the two interventions will be done upon study completion. Further research is necessary to confirm our findings.

Dynamics of a minimal model of interlocked positive and negative feedback loops of transcriptional regulation by cAMP-response element binding proteins.

cAMP-response element binding (CREB) proteins are involved in transcriptional regulation in a number of cellular processes (e.g., neural plasticity and circadian rhythms). The CREB family contains activators and repressors that may interact through positive and negative feedback loops. These loops can be generated by auto- and cross-regulation of expression of CREB proteins, via CRE elements in or near their genes. Experiments suggest that such feedback loops may operate in several systems (e.g., Aplysia and rat). To understand the functional implications of such feedback loops, which are interlocked via cross-regulation of transcription, a minimal model with a positive and negative loop was developed and investigated using bifurcation analysis. Bifurcation analysis revealed diverse nonlinear dynamics (e.g., bistability and oscillations). The stability of steady states or oscillations could be changed by time delays in the synthesis of the activator (CREB1) or the repressor (CREB2). Investigation of stochastic fluctuations due to small numbers of molecules of CREB1 and CREB2 revealed a bimodal distribution of CREB molecules in the bistability region. The robustness of the stable HIGH and LOW states of CREB expression to stochastic noise differs, and a critical number of molecules was required to sustain the HIGH state for days or longer. Increasing positive feedback or decreasing negative feedback also increased the lifetime of the HIGH state, and persistence of this state may correlate with long-term memory formation. A critical number of molecules was also required to sustain robust oscillations of CREB expression. If a steady state was near a deterministic Hopf bifurcation point, stochastic resonance could induce oscillations. This comparative analysis of deterministic and stochastic dynamics not only provides insights into the possible dynamics of CREB regulatory motifs, but also demonstrates a framework for understanding other regulatory processes with similar network architecture.

Lipid-protein interactions drive membrane protein topogenesis in accordance with the positive inside rule.

Transmembrane domain orientation within some membrane proteins is dependent on membrane lipid composition. Initial orientation occurs within the translocon, but final orientation is determined after membrane insertion by interactions within the protein and between lipid headgroups and protein extramembrane domains. Positively and negatively charged amino acids in extramembrane domains represent cytoplasmic retention and membrane translocation forces, respectively, which are determinants of protein orientation. Lipids with no net charge dampen the translocation potential of negative residues working in opposition to cytoplasmic retention of positive residues, thus allowing the functional presence of negative residues in cytoplasmic domains without affecting protein topology.

Immunopathology of postprimary tuberculosis: increased T-regulatory cells and DEC-205-positive foamy macrophages in cavitary lesions.

Postprimary tuberculosis occurs in immunocompetent people infected with Mycobacterium tuberculosis. It is restricted to the lung and accounts for 80% of cases and nearly 100% of transmission. Little is known about the immunopathology of postprimary tuberculosis due to limited availability of specimens. Tissues from 30 autopsy cases of pulmonary tuberculosis were located. Sections of characteristic lesions of caseating granulomas, lipid pneumonia, and cavitary stages of postprimary disease were selected for immunohistochemical studies of macrophages, lymphocytes, endothelial cells, and mycobacterial antigens. A higher percentage of cells in lipid pneumonia (36.1%) and cavitary lesions (27.8%) were positive for the dendritic cell marker DEC-205, compared to granulomas (9.0%, P < .05). Cavities contained significantly more T-regulatory cells (14.8%) than found in lipid pneumonia (5.2%) or granulomas (4.8%). Distribution of the immune cell types may contribute to the inability of the immune system to eradicate tuberculosis.

Dynamics of a minimal model of interlocked positive and negative feedback loops of transcriptional regulation by cAMP-response element binding proteins.

cAMP-response element binding (CREB) proteins are involved in transcriptional regulation in a number of cellular processes (e.g., neural plasticity and circadian rhythms). The CREB family contains activators and repressors that may interact through positive and negative feedback loops. These loops can be generated by auto- and cross-regulation of expression of CREB proteins, via CRE elements in or near their genes. Experiments suggest that such feedback loops may operate in several systems (e.g., Aplysia and rat). To understand the functional implications of such feedback loops, which are interlocked via cross-regulation of transcription, a minimal model with a positive and negative loop was developed and investigated using bifurcation analysis. Bifurcation analysis revealed diverse nonlinear dynamics (e.g., bistability and oscillations). The stability of steady states or oscillations could be changed by time delays in the synthesis of the activator (CREB1) or the repressor (CREB2). Investigation of stochastic fluctuations due to small numbers of molecules of CREB1 and CREB2 revealed a bimodal distribution of CREB molecules in the bistability region. The robustness of the stable HIGH and LOW states of CREB expression to stochastic noise differs, and a critical number of molecules was required to sustain the HIGH state for days or longer. Increasing positive feedback or decreasing negative feedback also increased the lifetime of the HIGH state, and persistence of this state may correlate with long-term memory formation. A critical number of molecules was also required to sustain robust oscillations of CREB expression. If a steady state was near a deterministic Hopf bifurcation point, stochastic resonance could induce oscillations. This comparative analysis of deterministic and stochastic dynamics not only provides insights into the possible dynamics of CREB regulatory motifs, but also demonstrates a framework for understanding other regulatory processes with similar network architecture.

Human TOB, an antiproliferative transcription factor, is a poly(A)-binding protein-dependent positive regulator of cytoplasmic mRNA deadenylation.

In mammalian cells, mRNA decay begins with deadenylation, which involves two consecutive phases mediated by the PAN2-PAN3 and the CCR4-CAF1 complexes, respectively. The regulation of the critical deadenylation step and its relationship with RNA-processing bodies (P-bodies), which are thought to be a site where poly(A)-shortened mRNAs get degraded, are poorly understood. Using the Tet-Off transcriptional pulsing approach to investigate mRNA decay in mouse NIH 3T3 fibroblasts, we found that TOB, an antiproliferative transcription factor, enhances mRNA deadenylation in vivo. Results from glutathione S-transferase pull-down and coimmunoprecipitation experiments indicate that TOB can simultaneously interact with the poly(A) nuclease complex CCR4-CAF1 and the cytoplasmic poly(A)-binding protein, PABPC1. Combining these findings with those from mutagenesis studies, we further identified the protein motifs on TOB and PABPC1 that are necessary for their interaction and found that interaction with PABPC1 is necessary for TOB's deadenylation-enhancing effect. Moreover, our immunofluorescence microscopy results revealed that TOB colocalizes with P-bodies, suggesting a role of TOB in linking deadenylation to the P-bodies. Our findings reveal a new mechanism by which the fate of mammalian mRNA is modulated at the deadenylation step by a protein that recruits poly(A) nuclease(s) to the 3' poly(A) tail-PABP complex.

Studies on the role of BCR in Philadelphia chromosome-positive leukemias

It is well established that the chimeric Bcr-Abl oncoprotein resulting from fusing 3$\sp\prime$ ABL sequences on chromosome 9 to 5$\sp\prime$ BCR sequences on chromosome 22 is the primary cause of Philadelphia chromosome-positive (Ph$\sp1$) leukemias. Although it is clear that the cis-Bcr sequence present within Bcr-Abl is able to activate the tyrosine kinase activity and F-actin binding capacity of Bcr-Abl which is critical for the transforming ability of BCR-ABL, the biological role of normal BCR gene product (P160 BCR) remains largely unknown. The previous finding by our lab that P160 BCR forms stable complexes with Bcr-Abl oncoprotein in Ph$\sp1$-positive leukemic cells implicated P160 BCR in the pathogenesis of Ph$\sp1$-positive leukemias. Here, we demonstrated that P160 BCR physically interacts with P210 BCR-ABL and become tyrosine phosphorylated when co-expressed with P210 BCR-ABL in COS1 cells while no tyrosine phosphorylation of P160 BCR can be detected when it is expressed alone. The results suggest that P160 BCR is a target for the Bcr-Abl tyrosine kinase. Although we were unable to detect stable physical interaction between P160 BCR and P145 c-ABL (Ib) in COS1 cells overexpressing both proteins, P160 BCR was phosphorylated on tyrosine residues when co-expressed with activated tyrosine kinase of P145 c-ABL (Ib). In addition, studies of tyrosine phosphorylation of BCR deletion mutants and 2-dimensional tryptic mapping of in vitro phosphorylated wild type and mutant (tyrosine to phenylalanine) Bcr-Abl indicated that tyrosine 177, 283 and 360 of Bcr represent some of the phosphorylation sites. Even though the significance of tyrosine phosphorylation of residues 283 and 360 of Bcr has not been determined, tyrosine phosphorylation of residue 177 within Bcr-Abl has been reported to be critical for its interaction with Grb2 molecule and subsequent activation of Ras signaling pathway. Here, we further demonstrated that tyrosine 177 phosphorylated P160 BCR is also able to bind to Grb2 molecule suggesting the role of P160 BCR in the Ras signaling pathway.^ Surprisingly, using 3$\sp\prime$ BCR antisense oligonucleotide to reduce the expression of P160 BCR without interfering with the expression of BCR-ABL resulted in increased growth or survival of B15 cells and M3.16 cells expressing either P185 BCR-ABL or P210 BCR-ABL respectively. The results provided strong arguments that P160 BCR may function as a negative regulator for cell growth.^ Considering all these results, we hypothesize that P160 BCR negatively regulate cell growth and tyrosine phosphorylation of P160 BCR turns off its growth suppressor function and turns on its growth stimulatory function. We further speculate that Bcr-Abl oncoprotein in leukemia cells stably interacts with and constitutively phosphorylates portions of P160 BCR converting it into a growth stimulatory state. In normal cells, the growth suppressor effects of P160 BCR could only be transiently and conditionally switched to growth stimulatory action by a strictly regulated cellular tyrosine kinase such as c-ABL. The model will be further discussed in the text. ^

Outcomes of tuberculosis positive non-injection drug users in Harris County from October 1995 through September 2004

Background. The population-based Houston Tuberculosis Initiative (HTI) study has enrolled and gathered demographic, social, behavioral, and disease related data on more than 80% of all reported Mycobacterium Tuberculosis (MTB) cases and 90% of all culture positive patients in Houston/Harris County over a 9 year period (from October 1995-September 2004). During this time period 33% (n=1210) of HTI MTB cases have reported a history of drug use. Of those MTB cases reporting a history of drug use, a majority of them (73.6%), are non-injection drug users (NIDUs). ^ Other than HIV, drug use is the single most important risk factor for progression from latent to infectious tuberculosis (TB). In addition, drug use is associated with increased transmission of active TB, as seen by the increased number of clonally related strains or clusters (see definition on page 30) found in this population. The deregulatory effects of drug use on immune function are well documented. Associations between drug use and increased morbidity have been reported since the late 1970's. However, limited research focused on the immunological consequence of non-injection drug use and its relation to tuberculosis infection among TB patients is available. ^ Methods. TB transmission patterns, symptoms, and prevalence of co-morbidities were a focus of this project. Smoking is known to suppress Nitric Oxide (NO) production and interfere with immune function. In order to limit any possible confounding due to smoking two separate analyses were done. Non-injection drug user smokers (NIDU-S) were compared to non-drug user smokers (NDU-S) and non-injection drug user non-smokers (NIDU-NS) were compared to non-drug user non-smokers (NDU-NS) individually. Specifically proportions, chi-square p-values, and (where appropriate) odds ratios with 95% confidence intervals were calculated to assess characteristics and potential associations of co-morbidities and symptoms of TB among NIDUs HTI TB cases. ^ Results. Significant differences in demographic characteristics and risk factors were found. In addition drug users were found to have a decreased risk for cancer, diabetes mellitus, and chronic pulmonary disease. They were at increased risk of having HIV/AIDS diagnosis, liver disease, and trauma related morbidities. Drug users were more likely to have pulmonary TB disease, and a significantly increased amount of clonally related strains of TB or "clusters" were seen in both smokers and non-smoker drug users when compared to their non-drug user counterparts. Drug users are more likely to belong to print groups (clonally related TB strains with matching spoligotypes) including print one and print three and the Beijing family group, s1. Drug users were found to be no more likely to experience drug resistance to TB therapy and were likely to be cured of disease upon completion of therapy. ^ Conclusion. Drug users demographic and behavioral risk factors put them at an increased risk contracting and spreading TB disease throughout the community. Their increased levels of clustering are evidence of recent transmission and the significance of certain print groups among this population indicate the transmission is from within the social family. For these reasons a focus on this "at risk population" is critical to the success of future public health interventions. Successful completion of directly observed therapy (DOT), the tracking of TB outbreaks and incidence through molecular characterization, and increased diagnostic strategies have led to the stabilization of TB incidence in Houston, Harris County over the past 9 years and proven that the Houston Tuberculosis Initiative has played a critical role in the control and prevention of TB transmission. ^

Antiretroviral therapy adherence and the use of condoms among African American HIV-positive crack cocaine users

Safer sex practices, such as consistent condom use, are essential to reduce HIV transmission. Determining causes and/or co-variants related to the likelihood of participating in high-risk sexual behaviors may allow the content of interventions and treatments to minimize HIV transmission to be tailored more effectively. The goal of this study was to examine whether a relationship exists between consistent condom use among African American HIV-positive crack cocaine users and both (1) the use of antiretroviral therapy, and (2) adherence to antiretroviral therapy regimens. The study population consisted of 390 participants. They were at least 18 years old, African American, HIV-positive, and had used crack cocaine within a month prior to an interview conducted sometime between April, 2004, and September, 2007. Bivariate associations were examined using contingency tables and χ2-statistics. The Mantel-Haenszel method was used to control for confounding. This study found neither a significant relationship between use of antiretroviral therapy and consistent condom use (Odds ratio (OR) = 1.38; 95% Confidence interval (95%CI) = 0.86–2.22), nor an association between antiretroviral therapy adherence and consistent condom use (OR = 1.02, 95%CI = 0.60–1.75). The exception was more consistent condom use when sex was traded for money or drugs in those on antiretroviral therapy, compared to those not on such therapy (OR = 2.28, 95%CI = 1.08–4.85). Further studies examining condom use and HIV treatment adherence are recommended. ^