Immune responses that are caused by seizures or that can contribute to epileptogenesis are poorly understood. Lymphocyte immune responses in brain after a single seizure are unknown. We developed a new murine model system to analyze early brain immune responses after a single generalized tonic clonic seizure. C57bl/6 mice (males, 6-8 wk old) received either sham (electrodes placed subcutaneously over frontal lobe but no current passed) or electrical stimulus (electrodes placed subcutaneously over frontal lobe, 15-30 mA, 100 Hz, 0.4ms burst duration, 1 sec train duration) that resulted in submaximal (no hind-limb extension) or maximal seizures (hind-limb extension). Pretreatment of mice with pentobarbital (i.p., 25mg/kg) or inhaled ethyl-chloride (for 20s) prevented convulsions. Mice were killed at 1-24 hr and 7 days, brains pooled, and single-cell suspensions prepared, after which cells were separated according to density (Percoll gradients) and cell numbers determined (flow cytometry). In some experiments, brain was dissected into neocortex, hippocampus, midbrain, and cerebellum before assay. This is the first report that a single maximal seizure induced by frontal electric stimulus results in increased lymphocyte numbers in brain. This effect was not obtained when similar frontal electric stimulus resulted in submaximal seizures, or when mice were pretreated with pentobarbital or ethyl-chloride. The increases in lymphocyte numbers after maximal seizure were predominantly in neocortex (CD4+ and CD8+ T and B cells) and in hippocampus (T cells). The T and B cell subsets also expressed high levels of the activation markers/adhesion receptors CD11a, CD29, and CD44, which are required for lymphocyte migration into brain. After seizure, these markers were upregulated on peripheral T and B cells before T and B cell numbers increased in brain, suggesting that the increases in these cells in brain are due to their entry from the periphery. CD4+ and CD8+ T cells in brain intracytoplasmically expressed IL-2, a cytokine that is a potent stimulator of lymphocyte proliferation and enhances the killing activity of cytotoxic T cells. CD4+ T cells also expressed IL-4, the cytokine required for IgE isotype switching by B cells. B cells in brain was IgG+ and IgE+, setting the stage for immune responses, and even allergic response in brain. CD8+ T cells expressed IFN-g and TNF-a, cytokines that activate microglia and brain macrophages. Taken together, the results indicate that there are early immune responses in brain after a single seizure, which may play a role in allergy/autoimmunity, synaptic remodeling, and in the development of epilepsy.

Multiple myeloma (MM), a bone marrow (BM) neoplasm of B-lymphocytes arrested in their maturation at the pre-plasma cell stage of differentiation, is the second most common hematologic malignancy in the U.S. Despite prolonged median survival with anti-myeloma strategies aimed at the tumor and its BM microenvironment, MM remains invariably fatal. Endothelial progenitor cells (EPCs) are CD133+/KDR+ cells that originate in the BM and play a key role in providing tumor neoangiogenesis, growth and MM progression. Using X-chromosome inactivation and RT-PCR analyses, our lab previously found EPCs from MM patients to be clonally restricted and genetically similar to tumor cells in approximately 60% of patients. Based on genetic similarity between EPCs and tumor cells in MM that we and other laboratories have demonstrated, my thesis explored the hypothesis that the clonal EPC population contains CD133+ MM precursor cells capable of self-renewal, and differentiation into a tumorigenic population. Results of my experiments strongly suggest that at least a subset of CD133+ cells qualify as MM progenitor cells evidenced by: (1) engraftment and differentiation of BM derived EPCs from MM patients in vivo in NOD/SCID mice; (2) in vitro and in vivo studies showing the differentiation of CD133+ cells from patients with MM into cells with a multiple myeloma cell phenotype (CD138/38+cells); (3) analysis of gene expression microarray studies showing upregulation of genes involved in stem cell function. Furthermore, I show the in vivo anti-myeloma effects of targeting Hsp70 whose gene expression is upregulated in MM. Taken together, my studies investigated MM pathogenesis through the in vivo characterization of progenitor cells as well as through genomic analyses, and targeting of a dysregulated pathway within EPCs and tumor cells which may be clinically effective.

Claustrum is a region of grey matter between the striatum and cerebral cortex that is among the most well-connected structures in the brain. It is hypothesized to function as a high-level coordinator of brain-wide activities like the integration of senses, attention, sleep, and consciousness. The exact anatomical boundaries of claustrum have been controversial and claustral subregions have not been well-defined. This may be in part due to its compact structure in rodents and other commonly studied species. In contrast, Seba’s short-tailed fruit (Carollia perspicillata) bat has a remarkably large claustrum, lending itself as a model and magnified view for investigating claustrum. We studied the distributions of the claustral marker latexin and the calcium-binding proteins calbindin, calretinin, and parvalbumin in claustrum. Using these markers, we defined clear claustral boundaries and several distinct subregions. The calcium-binding proteins (markers of different inhibitory neurons subtypes) were differentially distributed among subregions, suggesting that these regions are under the control of different inhibitory systems. In addition to having a large claustrum, Carollia is a relatively long-lived species, lending itself as a model for the neurobiology of aging and neurodegeneration. Two brain regions highly affected in the aging process are retrosplenial cortex (Brodmann areas 29 and 30) and hippocampus. In the course of this work, we found latexin was present in retrosplenial cortex, a region involved in memory and navigation, but only in Brodmann areas 29a and 29b. This distinct division of retrosplenial cortex differs from cytoarchitecturally-defined divisions but aligns with connectivity evidence that supports the separate grouping of areas 29a and 29b from areas 29c and 30. Finally, we found, several features of Carollia hippocampus including a compacted CA3 cell layer and a prosubiculum that are also present in primate but not rodent hippocampus. Due to these unique neuroanatomical features, Carollia may offer advantages in studying claustrum and other limbic cortical structures, especially in the context of aging, that are not present in more commonly studied model species.

Brain machine interfaces (BMIs) aim to restore lost motor functions by channeling movement-related brain signals to end-effectors skipping compromized parts of the central nervous system (CNS.) As there is increasing number of patients who can potentialy benefit from such help, there is a very urgent demand for optimizing and controlling the outputs of such devices. These BMI devices are currently is far from performing the every day and seemingly unintelligent acts of reaching, grasping, object manipulation, force-adaptation and motor learning. This is because these acts call on the CNS to make complex computations on its visual, proprioceptive and cutaneous inputs which artificial limbs lack, the main reason why even the best BMIs still give unstable movements. Efforts are now underway to create artificial proprioceptive and cutaneous inputs to BMIs. However, due to lack of thorough understanding of its effects on the brain and BMI movements, the presently accepted candidate for such a feedback channel, Microstimulation (MiSt) of the primary somatosensory cortex (S1), is not yet fully functional. Numerous critical questions have yet to be addressed, such as which S1 area and layer to target, what stimulus parameters to use, if unwanted side-effects, such as brain lesions, movement etc. should be major concerns, and many more. Moreover, we asked, why not even microstimulate other brain areas? Currently, there is little information on MiSt for somatosensation in other brain areas, such as the thalamus. This thesis aimed at: 1) Finding the discernable differences and similarities between the two inputs, natural and artificial (MiSt in S1 cortex and the VPL thalamus); 2) Finding the best region, cortex or VPL, where MiSt gives the most natural-looking response in S1 cortex; 3) Studying the dynamics of causal information transfer in thalamocortical networks in natural and MiSt for somatosensory neuroprosthesis to investigate possible behavioral consequences. MiSt was applied to S1 cortex and VPL thalamus of a monkey (multiple implants) and rats implanted with multielectrode and multiwire arrays respectively. The resulting spike and Local Field Potential (LFP) cortical and thalamic activities were recorded and analyzed per the goals of the thesis. The main findings indicate that cortical responses in both input conditions are comparable and that VPL MiSt may be a better candidate for somatosensory neuroprosthesis mainly because it causes reduced or no cortical inhibition. The results show that the different stimulation conditions have specific effects on the causal interaction in and between the two brain regions.

Objective: To evaluate associations between work-related stress, stressful life events, and perceived stress and semen quality. Design: Cross-sectional analysis. Setting: Northern California. Patient(s): 193 men from the Child Health and Development Studies evaluated between 2005-2008. Intervention(s): None. Main outcome measure(s): Measures of stress including job strain, perceived stress, and stressful life events; outcome measures of sperm concentration, percentage of motile sperm, and percentage of morphologically normal sperm. Result(s): We found an inverse association between perceived stress score and sperm concentration (estimated coefficient b=-0.09×10(3)/mL; 95% confidence interval [CI]=-0.18, -0.01), motility (b=-0.39; 95% CI=-0.79, 0.01), and morphology (b=-0.14; 95% CI, -0.25, -0.04) in covariate-adjusted linear regression analyses. Men who experienced two or more stressful life events in the past year compared with no stressful events had a lower percentage of motile sperm (b=-8.22; 95% CI, -14.31, -2.13) and a lower percentage of morphologically normal sperm (b=-1.66; 95% CI, -3.35, 0.03) but a similar sperm concentration. Job strain was not associated with semen parameters. Conclusion(s): In this first study to examine all three domains of stress, perceived stress and stressful life events but not work-related stress were associated with semen quality.

Objectives: The role of occupation in the development of cardiovascular disease (CVD) remains a topic of research because few studies have examined longitudinal associations, and because occupation can be an indicator of socioeconomic position (SEP) and a proxy for hazard exposure. This study examines associations of occupational category as an SEP marker and selected occupational exposures with progression of the subclinical carotid artery disease. Methods: A community-based, multiethnic sample (n=3109, mean age=60.2) provided subclinical CVD measures at least twice at three data collection points (mean follow-up=9.4 years). After accounting for demographic characteristics, SEP, and traditional CVD risk factors, we modelled common carotid intima-media thickness, carotid plaque scores, and carotid plaque shadowing as a function of occupational category, physical hazard exposure, physical activity on the job, interpersonal stress, job control and job demands. These job characteristics were derived from the Occupational Resource Network (O*NET). Random coefficient models were used to account for repeated measures and time-varying covariates. Results: There were a few statistically significant associations at baseline. After all covariates were included in the model, men in management, office/sales, service and blue-collar jobs had 28-44% higher plaque scores than professionals at baseline (p=0.001). Physically hazardous jobs were positively associated with plaque scores among women (p=0.014). However, there were no significant longitudinal associations between any of the occupational characteristics and any of the subclinical CVD measures. Conclusions: There was little evidence that the occupational characteristics examined in this study accelerated the progression of subclinical CVD.

Objective: To assess associations of occupational categories and job characteristics with prevalent hypertension. Methods: We analyzed 2517 Multi-Ethnic Study of Atherosclerosis participants, working 20+ hours per week, in 2002 to 2004. Results: Higher job decision latitude was associated with a lower prevalence of hypertension, prevalence ratio = 0.78 (95% confidence interval 0.66 to 0.91) for the top versus bottom quartile of job decision latitude. Associations, however, differed by occupation: decision latitude was associated with a higher prevalence of hypertension in health care support occupations (interaction P = 0.02). Occupation modified associations of sex with hypertension: a higher prevalence of hypertension in women (vs men) was observed in health care support and in blue-collar occupations (interaction P = 0.03). Conclusions: Lower job decision latitude is associated with hypertension prevalence in many occupations. Further research is needed to determine reasons for differential impact of decision latitude and sex on hypertension across occupations.

Objectives: The prognostic utility of lifestyle risk factors and job-related conditions (LS&JRC) for cardiovascular disease (CVD) risk stratification remains to be clarified. Methods: We investigated discrimination and clinical utility of LS&JRC among 2532 workers, 35-64 years old, CVD-free at the time of recruitment (1989-1996) in four prospective cohorts in Northern Italy, and followed up (median 14 years) until first major coronary event or ischemic stroke, fatal or non-fatal. From a Cox model including cigarette smoking, alcohol intake, occupational and sport physical activity and job strain, we estimated 10-year discrimination as the area under the ROC curve (AUC), and clinical utility as the Net Benefit. Results: N = 162 events occurred during follow-up (10-year risk: 4.3%). The LS&JRC model showed the same discrimination (AUC = 0.753, 95% CI 0.700-0.780) as blood lipids, blood pressure, smoking and diabetes (AUC = 0.753), consistently across occupational classes. Among workers at low CVD risk (n = 1832, 91 CVD events), 687 were at increased LS&JRC risk; of these, 1 every 15 was a case, resulting in a positive Net Benefit (1.27; 95% CI 0.68-2.16). Conclusions: LS&JRC are as accurate as clinical risk factors in identifying future cardiovascular events among working males. Our results support initiatives to improve total health at work as strategies to prevent cardiovascular disease.

Background: The World Health Organization (WHO) and the International Labour Organization (ILO) are developing Joint Estimates of the work-related burden of disease and injury (WHO/ILO Joint Estimates), with contributions from a large network of experts. Evidence from mechanistic data suggests that exposure to long working hours may cause ischaemic heart disease (IHD). In this paper, we present a systematic review and meta-analysis of parameters for estimating the number of deaths and disability-adjusted life years from IHD that are attributable to exposure to long working hours, for the development of the WHO/ILO Joint Estimates. Objectives: We aimed to systematically review and meta-analyse estimates of the effect of exposure to long working hours (three categories: 41-48, 49-54 and ≥55 h/week), compared with exposure to standard working hours (35-40 h/week), on IHD (three outcomes: prevalence, incidence and mortality). Data sources: We developed and published a protocol, applying the Navigation Guide as an organizing systematic review framework where feasible. We searched electronic databases for potentially relevant records from published and unpublished studies, including MEDLINE, Scopus, Web of Science, CISDOC, PsycINFO, and WHO ICTRP. We also searched grey literature databases, Internet search engines and organizational websites; hand-searched reference lists of previous systematic reviews; and consulted additional experts. Study eligibility and criteria: We included working-age (≥15 years) workers in the formal and informal economy in any WHO and/or ILO Member State but excluded children (aged < 15 years) and unpaid domestic workers. We included randomized controlled trials, cohort studies, case-control studies and other non-randomized intervention studies which contained an estimate of the effect of exposure to long working hours (41-48, 49-54 and ≥55 h/week), compared with exposure to standard working hours (35-40 h/week), on IHD (prevalence, incidence or mortality). Study appraisal and synthesis methods: At least two review authors independently screened titles and abstracts against the eligibility criteria at a first stage and full texts of potentially eligible records at a second stage, followed by extraction of data from qualifying studies. Missing data were requested from principal study authors. We combined relative risks using random-effect meta-analysis. Two or more review authors assessed the risk of bias, quality of evidence and strength of evidence, using Navigation Guide and GRADE tools and approaches adapted to this project. Results: Thirty-seven studies (26 prospective cohort studies and 11 case-control studies) met the inclusion criteria, comprising a total of 768,751 participants (310,954 females) in 13 countries in three WHO regions (Americas, Europe and Western Pacific). The exposure was measured using self-reports in all studies, and the outcome was assessed with administrative health records (30 studies) or self-reported physician diagnosis (7 studies). The outcome was defined as incident non-fatal IHD event in 19 studies (8 cohort studies, 11 case-control studies), incident fatal IHD event in two studies (both cohort studies), and incident non-fatal or fatal ("mixed") event in 16 studies (all cohort studies). Because we judged cohort studies to have a relatively lower risk of bias, we prioritized evidence from these studies and treated evidence from case-control studies as supporting evidence. For the bodies of evidence for both outcomes with any eligible studies (i.e. IHD incidence and mortality), we did not have serious concerns for risk of bias (at least for the cohort studies). No eligible study was found on the effect of long working hours on IHD prevalence. Compared with working 35-40 h/week, we are uncertain about the effect on acquiring (or incidence of) IHD of working 41-48 h/week (relative risk (RR) 0.98, 95% confidence interval (CI) 0.91 to 1.07, 20 studies, 312,209 participants, I2 0%, low quality of evidence) and 49-54 h/week (RR 1.05, 95% CI 0.94 to 1.17, 18 studies, 308,405 participants, I2 0%, low quality of evidence). Compared with working 35-40 h/week, working ≥55 h/week may have led to a moderately, clinically meaningful increase in the risk of acquiring IHD, when followed up between one year and 20 years (RR 1.13, 95% CI 1.02 to 1.26, 22 studies, 339,680 participants, I2 5%, moderate quality of evidence). Compared with working 35-40 h/week, we are very uncertain about the effect on dying (mortality) from IHD of working 41-48 h/week (RR 0.99, 95% CI 0.88 to 1.12, 13 studies, 288,278 participants, I2 8%, low quality of evidence) and 49-54 h/week (RR 1.01, 95% CI 0.82 to 1.25, 11 studies, 284,474 participants, I2 13%, low quality of evidence). Compared with working 35-40 h/week, working ≥55 h/week may have led to a moderate, clinically meaningful increase in the risk of dying from IHD when followed up between eight and 30 years (RR 1.17, 95% CI 1.05 to 1.31, 16 studies, 726,803 participants, I2 0%, moderate quality of evidence). Subgroup analyses found no evidence for differences by WHO region and sex, but RRs were higher among persons with lower SES. Sensitivity analyses found no differences by outcome definition (exclusively non-fatal or fatal versus "mixed"), outcome measurement (health records versus self-reports) and risk of bias ("high"/"probably high" ratings in any domain versus "low"/"probably low" in all domains). Conclusions: We judged the existing bodies of evidence for human evidence as "inadequate evidence for harmfulness" for the exposure categories 41-48 and 49-54 h/week for IHD prevalence, incidence and mortality, and for the exposure category ≥55 h/week for IHD prevalence. Evidence on exposure to working ≥55 h/week was judged as "sufficient evidence of harmfulness" for IHD incidence and mortality. Producing estimates for the burden of IHD attributable to exposure to working ≥55 h/week appears evidence-based, and the pooled effect estimates presented in this systematic review could be used as input data for the WHO/ILO Joint Estimates.