Activation of heat shock and antioxidant responses by the natural product celastrol: transcriptional signatures of a thiol-targeted molecule.

Stress response pathways allow cells to sense and respond to environmental changes and adverse pathophysiological states. Pharmacological modulation of cellular stress pathways has implications in the treatment of human diseases, including neurodegenerative disorders, cardiovascular disease, and cancer. The quinone methide triterpene celastrol, derived from a traditional Chinese medicinal herb, has numerous pharmacological properties, and it is a potent activator of the mammalian heat shock transcription factor HSF1. However, its mode of action and spectrum of cellular targets are poorly understood. We show here that celastrol activates Hsf1 in Saccharomyces cerevisiae at a similar effective concentration seen in mammalian cells. Transcriptional profiling revealed that celastrol treatment induces a battery of oxidant defense genes in addition to heat shock genes. Celastrol activated the yeast Yap1 oxidant defense transcription factor via the carboxy-terminal redox center that responds to electrophilic compounds. Antioxidant response genes were likewise induced in mammalian cells, demonstrating that the activation of two major cell stress pathways by celastrol is conserved. We report that celastrol's biological effects, including inhibition of glucocorticoid receptor activity, can be blocked by the addition of excess free thiol, suggesting a chemical mechanism for biological activity based on modification of key reactive thiols by this natural product.

Parentage analysis with genetic markers in natural populations. I. The expected proportion of offspring with unambiguous paternity.

Recent studies indicate that polymorphic genetic markers are potentially helpful in resolving genealogical relationships among individuals in a natural population. Genetic data provide opportunities for paternity exclusion when genotypic incompatibilities are observed among individuals, and the present investigation examines the resolving power of genetic markers in unambiguous positive determination of paternity. Under the assumption that the mother for each offspring in a population is unambiguously known, an analytical expression for the fraction of males excluded from paternity is derived for the case where males and females may be derived from two different gene pools. This theoretical formulation can also be used to predict the fraction of births for each of which all but one male can be excluded from paternity. We show that even when the average probability of exclusion approaches unity, a substantial fraction of births yield equivocal mother-father-offspring determinations. The number of loci needed to increase the frequency of unambiguous determinations to a high level is beyond the scope of current electrophoretic studies in most species. Applications of this theory to electrophoretic data on Chamaelirium luteum (L.) shows that in 2255 offspring derived from 273 males and 70 females, only 57 triplets could be unequivocally determined with eight polymorphic protein loci, even though the average combined exclusionary power of these loci was 73%. The distribution of potentially compatible male parents, based on multilocus genotypes, was reasonably well predicted from the allele frequency data available for these loci. We demonstrate that genetic paternity analysis in natural populations cannot be reliably based on exclusionary principles alone. In order to measure the reproductive contributions of individuals in natural populations, more elaborate likelihood principles must be deployed.

Health Care Providers' Training Needs Related to Human Trafficking: Maximizing the Opportunity to Effectively Screen and Intervene

Human trafficking is a complex and multifaceted problem that takes the form of economic, physical and sexual exploitation of people, both adults and children, who are reduced to simple products for commerce. Human trafficking in the United States also has both a domestic and an international aspect. Health care providers are in a unique position to screen for victims of trafficking and may provide important medical and psychological care for victims while in captivity and thereafter. Trafficked persons are likely to suffer a wide spectrum of health risks that reflect the unique circumstances and experiences in a trafficked victim’s life. Although trafficked victims typically have experienced inadequate medical care, once contact is made by the victim with the health care professionals, the opportunity then exists to identify, treat, and assist such victims. The range of services and supports required to appropriately respond to human trafficking victims once identified is broad and typically goes beyond just what is immediately provided by the health care professional and includes safe housing, legal advice, income support, and, for international victims, immigration status related issues. An informed and responsive community is necessary to serve both the international and domestic victims of human trafficking, and needs assessments demonstrated a number of barriers that hindered the delivery of effective services to human trafficking victims. One of the consistent needs identified to combat these barriers was enhanced training among all professionals who might come in contact with human trafficking victims. We highlight the efforts of the Houston Rescue and Restore Coalition (HRRC), a local grassroots non-profit organization whose mission focuses on raising awareness of human trafficking in the Greater Houston Metropolitan area. HRRC responded to the consistent recommendation from various community needs assessments for additional training of front line professionals who would have the opportunity to identify human trafficking victims and supported the design and pilot testing of a health professions training program around human trafficking. Dissemination of this type of training along with careful evaluation and continued refinement will be one way for health care professionals to engage in a positive manner with human trafficking victims.

Distribution of genes encoding MSCRAMMs and Pili in clinical and natural populations of Enterococcus faecium.

Enterococcus faecium has recently emerged as an important cause of nosocomial infections. We previously identified 15 predicted surface proteins with characteristics of MSCRAMMs and/or pili and demonstrated that their genes were frequently present in 30 clinical E. faecium isolates studied; one of these, acm, has been studied in further detail. To determine the prevalence of the other 14 genes among various E. faecium populations, we have now assessed 433 E. faecium isolates, including 264 isolates from human clinical infections, 69 isolates from stools of hospitalized patients, 70 isolates from stools of community volunteers, and 30 isolates from animal-related sources. A variable distribution of the 14 genes was detected, with their presence ranging from 51% to 98% of isolates. While 81% of clinical isolates carried 13 or 14 of the 14 genes tested, none of the community group isolates and only 13% of animal isolates carried 13 or 14 genes. The presence of these genes was most frequent in endocarditis isolates, with 11 genes present in all isolates, followed by isolates from other clinical sources. The number of genes significantly associated with clinical versus fecal or animal origin (P = 0.04 to <0.0001) varied from 10 to 13, depending on whether comparisons were made against individual clinical subgroups (endocarditis, blood, and other clinical isolates) or against all clinical isolates combined as one group. The strong association of these genes with clinical isolates raises the possibility that their preservation/acquisition has favored the adaptation of E. faecium to nosocomial environments and/or patients.

Acquisition of a natural resistance gene renders a clinical strain of methicillin-resistant Staphylococcus aureus resistant to the synthetic antibiotic linezolid.

Linezolid, which targets the ribosome, is a new synthetic antibiotic that is used for treatment of infections caused by Gram-positive pathogens. Clinical resistance to linezolid, so far, has been developing only slowly and has involved exclusively target site mutations. We have discovered that linezolid resistance in a methicillin-resistant Staphylococcus aureus hospital strain from Colombia is determined by the presence of the cfr gene whose product, Cfr methyltransferase, modifies adenosine at position 2503 in 23S rRNA in the large ribosomal subunit. The molecular model of the linezolid-ribosome complex reveals localization of A2503 within the drug binding site. The natural function of cfr likely involves protection against natural antibiotics whose site of action overlaps that of linezolid. In the chromosome of the clinical strain, cfr is linked to ermB, a gene responsible for dimethylation of A2058 in 23S rRNA. Coexpression of these two genes confers resistance to all the clinically relevant antibiotics that target the large ribosomal subunit. The association of the ermB/cfr operon with transposon and plasmid genetic elements indicates its possible mobile nature. This is the first example of clinical resistance to the synthetic drug linezolid which involves a natural resistance gene with the capability of disseminating among Gram-positive pathogenic strains.

The role of peroxisome proliferator-activated receptors in the development and physiology of gametes and preimplantation embryos.

In several species, a family of nuclear receptors, the peroxisome proliferator-activated receptors (PPARs) composed of three isotypes, is expressed in somatic cells and germ cells of the ovary as well as the testis. Invalidation of these receptors in mice or stimulation of these receptors in vivo or in vitro showed that each receptor has physiological roles in the gamete maturation or the embryo development. In addition, synthetic PPAR gamma ligands are recently used to induce ovulation in women with polycystic ovary disease. These results reveal the positive actions of PPAR in reproduction. On the other hand, xenobiotics molecules (in herbicides, plasticizers, or components of personal care products), capable of activating PPAR, may disrupt normal PPAR functions in the ovary or the testis and have consequences on the quality of the gametes and the embryos. Despite the recent data obtained on the biological actions of PPARs in reproduction, relatively little is known about PPARs in gametes and embryos. This review summarizes the current knowledge on the expression and the function of PPARs as well as their partners, retinoid X receptors (RXRs), in germ cells and preimplantation embryos. The effects of natural and synthetic PPAR ligands will also be discussed from the perspectives of reproductive toxicology and assisted reproductive technology.

Mechanism of surgical stress impairment of murine natural killer cell cytotoxicity

Natural killer cells may provide an important first line of defense against metastatic implantation of solid tumors. This antitumor function occurs during the intravascular and visceral lodgment phase of cancer dissemination, as demonstrated in small animal metastasis models. The role of the NK cell in controlling human tumor dissemination is more difficult to confirm, at least partially because of ethical restraints on experimental design. Nonetheless, a large number of solid tumor patient studies have demonstrated NK cell cytolysis of both autologous and allogeneic tumors.^ Of the major cancer therapeutic modalities, successful surgery in conjunction with other treatments offers the best possibility of cure. However, small animal experiments have demonstrated that surgical stress can lead to increased rates of primary tumor take, and increased incidence, size, and rapidity of metastasis development. Because the physiologic impact of surgical stress can also markedly impair perioperative antitumor immune function in humans, we examined the effect of surgical stress on perioperative NK cell cytolytic function in a murine preclinical model. Our studies demonstrated that hindlimb amputation led to a marked impairment of postoperative NK cell cytotoxicity. The mechanism underlying this process is complex and involves the postsurgical generation of splenic erythroblasts that successfully compete with NK cells for tumor target binding sites; NK cell-directed suppressor cell populations; and a direct impairment of NK cell recycling capacity. The observed postoperative NK cell suppression could be prevented by in vivo administration of pyrimidinone biologic response modifiers or by short term in vitro exposure of effector cells to recombinant Interleukin-2. It is hoped that insights gained from this research may help in the future development of NK cell specific perioperative immunotherapy relevant to the solid tumor patients undergoing cancer resection. ^

The interaction of P160 BCR with BCR-ABL gene products unique to Philadelphia chromosome leukemias

The BCR gene is involved in the pathogenesis of Philadelphia chromosome-positive (Ph$\sp1$) leukemias. Typically, the 5$\sp\prime$ portion of BCR on chromosome 22 becomes fused to a 5$\sp\prime$ truncated ABL gene from chromosome 9 resulting in a chimeric BCR-ABL gene. To investigate the role of the BCR gene product, a number of BCR peptide sequences were used to generate anti-BCR antibodies for detection of BCR and BCR-ABL proteins. Since both BCR and ABL proteins have kinase activity, the anti-BCR antibodies were tested for their ability to immunoprecipitate BCR and BCR-ABL proteins from cellular lysates by use of an immunokinase assay. Antisera directed towards the C-terminal portions of P160 BCR, sequences not present in BCR-ABL proteins, were capable of co-immunoprecipitating P210 BCR-ABL from the Ph$\sp1$- positive cell line K562. Re-immunoprecipitation studies following complete denaturation showed that C-terminal BCR antisera specifically recognized P160 BCR but not P210 BCR-ABL. These and other results indicated the presence of a P160 BCR/P210 BCR-ABL protein complex in K562 cells. Experiments performed with Ph$\sp1$-positive ALL cells and uncultured Ph$\sp1$-positive patient white blood cells established the general presence of BCR/BCR-ABL protein complexes in BCR-ABL expressing cells. However, two cell lines derived from Ph$\sp1$-positive patients lacked P160 BCR/P210 BCR-ABL complexes. Lysates from one of these cell lines mixed with lysates from a cell line that expresses only P160 BCR failed to generate BCR/BCR-ABL protein complexes in vitro indicating that P160 BCR and P210 BCR-ABL do not simply oligomerize.^ Two-dimensional tryptic maps were performed on both BCR and BCR-ABL proteins labeled in vitro with $\sp{32}$P. These maps indicate that the autophosphorylation sites in BCR-ABL proteins are primarily located within BCR exon 1 sequences in both P210 and P185 BCR-ABL, and that P160 BCR is phosphorylated in trans in similar sites by the activated ABL kinase of both BCR-ABL proteins. These results provide strong evidence that P160 BCR serves as a target for the BCR-ABL oncoprotein.^ K562 cells, induced to terminally differentiate with the tumor promoter TPA, show a loss of P210 BCR-ABL kinase activity 12-18 hours after addition of TPA. This loss coincides with the loss of activity in P160 BCR/P210 BCR-ABL complexes but not with the loss of the P210 BCR-ABL, suggesting the existence of an inactive form of P210 BCR-ABL. However, a degraded BCR-ABL protein served as the kinase active form preferentially sequestered within the remaining BCR/BCR-ABL protein complex.^ The results described in this thesis form the basis for a model for BCR-ABL induced leukemias which is presented and discussed. ^

ANALYSIS OF THE CORYNEBACTERIUM PARVUM-INDUCED DECLINE OF MURINE NATURAL KILLER CELL-MEDIATED CYTOTOXICITY

Treatment of mice with the immunomodulating agent, Corynebacterium parvum (C. parvum), was shown to result in a severe and long-lasting depression of splenic natural killer (NK) cell-mediated cytotoxicity 5-21 days post-inoculation. Because NK cells have been implicated in immunosurveillance against malignancy (due to their spontaneous occurrence and rapid reactivity to a variety of histological types of tumors), as well as in resistance to established tumors, this decreased activity was of particular concern, since this effect is contrary to that which would be considered therapeutically desirable in cancer treatment (i.e. a potentiation of antitumor effector functions, including NK cell activity, would be expected to lead to a more effective destruction of malignant cells). Therefore, an analysis of the mechanism of this decline of splenic NK cell activity in C.parvum treated mice was undertaken.^ From in vitro co-culturing experiments, it was found that low NK-responsive C. parvum splenocytes were capable of reducing the normally high-reactivity of cells from untreated syngeneic mice to YAC-1 lymphoma, suggesting the presence of NK-directed suppressor cells in C. parvum treated animals. This was further supported by the demonstration of normal levels of cytotoxicity in C. parvum splenocyte preparations following Ficoll-Hypaque separation, which coincided with removal of the NK-suppressive capabilities of these cells. The T cell nature of these regulatory cells was indicated by (1) the failure of C. parvum to cause a reduction of NK cell activity, or the generation of NK-directed suppressor cells in T cell-deficient athymic mice, (2) the removal of C. parvum-induced suppression by T cell-depleting fractionation procedures or treatments, and (3) demonstration of suppression of NK cell activity by T cell-enriched C. parvum splenocytes. These studies suggest, therefore, that the eventual reduction of suppression by T cell elimination and/or inhibition, may result in a promotion of the antitumor effectiveness of C. parvum due to the contribution of "freed" NK effector cell activity.^ However, the temporary suppression of NK cell activity induced by C. parvum (reactivity of treated mice returns to normal levels within 28 days after C. parvum injection), may in fact be favorable in some situations, e.g. in bone marrow transplantation cases, since NK cells have been suggested to play a role also in the process of bone marrow graft rejection.^ Therefore, the discriminate use of agents such as C. parvum may allow for the controlled regulation of NK cell activity suggested to be necessary for the optimalization of therapeutic regimens. ^

Chronic lymphocytic leukemia: A study of the changing patterns of the natural history, clinical factors associated with prognosis, and risk of second cancers

A retrospective cohort study was conducted among 1542 patients diagnosed with CLL between 1970 and 2001 at the M. D. Anderson Cancer Center (MDACC). Changes in clinical characteristics and the impact of CLL on life expectancy were assessed across three decades (1970–2001) and the role of clinical factors on prognosis of CLL were evaluated among patients diagnosed between 1985 and 2001 using Kaplan-Meier and Cox proportional hazards method. Among 1485 CLL patients diagnosed from 1970 to 2001, patients in the recent cohort (1985–2001) were diagnosed at a younger age and an earlier stage compared to the earliest cohort (1970–1984). There was a 44% reduction in mortality among patients diagnosed in 1985–1995 compared to those diagnosed in 1970–1984 after adjusting for age, sex and Rai stage among patients who ever received treatment. There was an overall 11 years (5 years for stage 0) loss of life expectancy among 1485 patients compared with the expected life expectancy based on the age-, sex- and race-matched US general population, with a 43% decrease in the 10-year survival rate. Abnormal cytogenetics was associated with shorter progression-free (PF) survival after adjusting for age, sex, Rai stage and beta-2 microglobulin (beta-2M); whereas, older age, abnormal cytogenetics and a higher beta-2M level were adverse predictors for overall survival. No increased risk of second cancer overall was observed, however, patients who received treatment for CLL had an elevated risk of developing AML and HD. Two out of three patients who developed AML were treated with alkylating agents. In conclusion, CLL patients had improved survival over time. The identification of clinical predictors of PF/overall survival has important clinical significance. Close surveillance of the development of second cancer is critical to improve the quality of life of long-term survivors. ^

Cultural competence in an HIV dedicated dental clinic: Application of the National Standards for Culturally and Linguistically Appropriate Services in Health Care (CLAS)

This dissertation investigated perspectives on cultural competence among African-American women patients, staff, and the administrator of a dental clinic serving people living with HIV/AIDS; and evaluated the role of the National Standards for Culturally and Linguistically Appropriate Services in Health Care (CLAS) in advancing the provision of culturally competent care in the clinic. ^ The study was qualitative with data collection via focus groups and individual interviews with a sample of African-American women patients, and individual interviews with a sample of staff and the clinic administrator. Transcripts were coded and themes identified using the software program ATLAS.ti. A cultural audit template was developed and applied to evaluate cultural competency. ^ Among attitudes and behaviors that contributed to the provision of culturally competent care at the clinic were respect and empathic communication. Formal cultural competency was not featured strongly in the methods by which the staff learned to work with diverse populations. Instead cultural competence among the staff was based on thoughtful hiring practices, natural aptitude and a climate that encouraged learning through informal sharing of experiences. The staff and administrator felt that an African-American dentist would be an asset in improving culturally competent care at the clinic. Previous research and national policy also promote the provider-patient racial/ethnic concordance to improve care. In this study, however, the patients were happy with the care provided regardless of the race/ethnicity of the staff, probably reflecting the well developed cultural competence skills of clinic staff overall. ^ The clinic administrator was unaware of the CLAS standards although the clinic was implicitly operated under their mandates. This occurred because the clinic is supported by federal funding and the CLAS standards were incorporated into the requirements. Incorporation into and monitoring of the CLAS standards in federally funded programs therefore appears to be an effective means for ensuring that they are implemented. ^ This study illustrates that cultural competence, though not universally understood, can be systematically investigated to identify what constitutes appropriate care and the factors that support or inhibit it. Among important elements of culturally competent care are respect and empathic communication. ^

An overview of China's one child policy and health consequences on society

In 1979, China implemented the one child policy to stifle the burden of the massive demographic growth cast on the future economic development and quality of living conditions. At the time, a quarter of the world's population resided in China and occupied only 7 percent of the world's arable land (The World Factbook, 2006). The government set the target total population to about 1.4 billion for the year 2010 and to significantly reduce the natural increase rate. First this overview paper will describe population demographics and economy of China's society. This paper will also investigate what the one child policy entails and how it is implemented. Furthermore, the consequences of the policy in regard to population growth, sex ratio, marital discrepancies, adverse health of mother and child, aging population, and pension coverage will be examined. Finally, future recommendations and an alternative policy will be postulated to increase the effectiveness of the policy and improve its effects on health. ^

A model for use by local public health departments to evaluate pandemic influenza plans

The events of the 1990's and early 2000's demonstrated the need for effective planning and response to natural and man-made disasters. One of those potential natural disasters is pandemic flu. Once defined, the CDC stated that program, or plan, effectiveness is improved through the process of program evaluation. (Centers for Disease Control and Prevention, 1999) Program evaluation should be accomplished not only periodically, but in the course of routine administration of the program. (Centers for Disease Control and Prevention, 1999) Accomplishing this task for a "rare, but significant event" is challenging. (Herbold, John R., PhD., 2008) To address this challenge, the RAND Corporation (under contract to the CDC) developed the "Facilitated Look-Backs" approach that was tested and validated at the state level. (Aledort et al., 2006).^ Nevertheless, no comprehensive and generally applicable pandemic influenza program evaluation tool or model is readily found for use at the local public health department level. This project developed such a model based on the "Facilitated Look-Backs" approach developed by RAND Corporation. (Aledort et al., 2006) Modifications to the RAND model included stakeholder additions, inclusion of all six CDC program evaluation steps, and suggestions for incorporating pandemic flu response plans in seasonal flu management implementation. Feedback on the model was then obtained from three LPHD's—one rural, one suburban, and one urban. These recommendations were incorporated into the final model. Feedback from the sites also supported the assumption that this model promotes the effective and efficient evaluation of both pandemic flu and seasonal flu response by reducing redundant evaluations of pandemic flu plans, seasonal flu plans, and funding requirement accountability. Site feedback also demonstrated that the model is comprehensive and flexible, so it can be adapted and applied to different LPHD needs and settings. It also stimulates evaluation of the major issues associated with pandemic flu planning. ^ The next phase in evaluating this model should be to apply it in a program evaluation of one or more LPHD's seasonal flu response that incorporates pandemic flu response plans.^

Health impacts of extreme weather: Flood fatalities in Texas

Floods are the leading cause of fatalities related to natural disasters in Texas. Texas leads the nation in flash flood fatalities. From 1959 through 2009 there were three times more fatalities in Texas (840) than the following state Pennsylvania (265). Texas also leads the nation in flood-related injuries (7753). Flood fatalities in Texas represent a serious public health problem. This study addresses several objectives of Healthy People 2010 including reducing deaths from motor vehicle accidents (Objective 15-15), reducing nonfatal motor vehicle injuries (Objective 15-17), and reducing drownings (Objective 15-29). The study examined flood fatalities that occurred in Texas between 1959 and 2008. Flood fatality statistics were extracted from three sources: flood fatality databases from the National Climatic Data Center, the Spatial Hazard Event and Loss Database for the United States, and the Texas Department of State Health Services. The data collected for flood fatalities include the date, time, gender, age, location, and type of flood. Inconsistencies among the three databases were identified and discussed. Analysis reveals that most fatalities result from driving into flood water (77%). Spatial analysis indicates that more fatalities occurred in counties containing major urban centers – some of the Flash Flood Alley counties (Bexar, Dallas, Travis, and Tarrant), Harris County (Houston), and Val Verde County (Del Rio). An intervention strategy targeting the behavior of driving into flood water is proposed. The intervention is based on the Health Belief model. The main recommendation of the study is that flood fatalities in Texas can be reduced through a combination of improved hydrometeorological forecasting, educational programs aimed at enhancing the public awareness of flood risk and the seriousness of flood warnings, and timely and appropriate action by local emergency and safety authorities.^

Policy implications of public health workforce development for disaster preparedness in the United States

Public health efforts were initiated in the United States with legislative actions for enhancing food safety and ensuring pure drinking water. Some additional policy initiatives during the early 20th century helped organize and coordinate relief efforts for victims of natural disasters. By 1950's the federal government expanded its role for providing better health and safety to the communities, and its disaster relief activities became more structured. A rise in terrorism related incidents during the late 1990's prompted new proactive policy directions. The traditional policy and program efforts for rescue, recovery, and relief measures changed focus to include disaster preparedness and countermeasures against terrorism.^ The study took a holistic approach by analyzing all major disaster related policies and programs, in regard to their structure, process, and outcome. Study determined that United States has a strong disaster preparedness agenda and appropriate programs are in place with adequate policy support, and the country is prepared to meet all possible security challenges that may arise in the future. The man-made disaster of September 11th gave a major thrust to improve security and enhance preparedness of the country. These new efforts required large additional funding from the federal government. Most existing preparedness programs at the local and national levels are run with federal funds which is insufficient in some cases. This discrepancy arises from the fact that federal funding for disaster preparedness programs at present are not allocated by the level of risks to individual states or according to the risks that can be assigned to critical infrastructures across the country. However, the increased role of the federal government in public health affairs of the states is unusual, and opposed to the spirit of our constitution where sovereignty is equally divided between the federal government and the states. There is also shortage of manpower in public health to engage in disaster preparedness activities, despite some remarkable progress following the September 11th disaster.^ Study found that there was a significant improvement in knowledge and limited number of studies showed improvement of skills, increase in confidence and improvement in message-mapping. Among healthcare and allied healthcare professionals, short-term training on disaster preparedness increased knowledge and improved personal protective equipment use with some limited improvement in confidence and skills. However, due to the heterogeneity of these studies, the results and interpretation of this systematic review may be interpreted with caution.^