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Phosphotyrosines in the killer cell inhibitory receptor motif of NKB1 are required for negative signaling and for association with protein tyrosine phosphatase 1C.
NKB1 is one member of a growing family of killer cell inhibitory receptors (KIR). It is expressed on natural killer (NK) cells and T cells, and has been shown to inhibit cytolytic functions of these cells upon interacting with its ligand, HLA-B (Bw4). We demonstrate here that the cytoplasmic region of NKB1 is capable of inhibiting T cell activation in Jurkat cells. The tyrosine phosphorylation of the NKB1 KIR consensus motif, YxxL(x)26 YxxL, induces an association with the protein tyrosine phosphatase 1C (PTP1C). Importantly, mutation of both tyrosines in the motif abolished the inhibitory functions of NKB1 and abrogated PTP1C association. Mutational analysis of the individual tyrosines suggest that the membrane proximal tyrosine may play a crucial role in mediating the inhibitory signal. These results demonstrate that KIR can not only inhibit cytolytic activity, but can also negatively regulate T cell receptor activation events that lead to downstream gene activation, and further supports a model that implicates PTP1C as a mediator in the KIR inhibitory signal
Pharmacovigilance in India, Uganda and South Africa with reference to WHO's minimum requirements.
BACKGROUND: Pharmacovigilance (PV) data are crucial for ensuring safety and effectiveness of medicines after drugs have been granted marketing approval. This paper describes the PV systems of India, Uganda and South Africa based on literature and Key Informant (KI) interviews and compares them with the World Health Organization's (WHO's) minimum PV requirements for a Functional National PV System. METHODS: A documentary analysis of academic literature and policy reports was undertaken to assess the medicines regulatory systems and policies in the three countries. A gap analysis from the document review indicated a need for further research in PV. KI interviews covered topics on PV: structure and practices of the system; current regulatory policy; capacity limitations, staffing, funding and training; availability and reporting of data; and awareness and usage of the systems. Twenty interviews were conducted in India, 8 in Uganda and 11 in South Africa with government officials from the ministries of health, national regulatory authorities, pharmaceutical producers, Non-Governmental Organizations (NGOs), members of professional associations and academia. The findings from the literature and KI interviews were compared with WHO's minimum requirements. RESULTS: All three countries were confronted with similar barriers: lack of sufficient funding, limited number of trained staff, inadequate training programs, unclear roles and poor coordination of activities. Although KI interviews represented viewpoints of the respondents, the findings confirmed the documentary analysis of the literature. Although South Africa has a legal requirement for PV, we found that the three countries uniformly lacked adequate capacity to monitor medicines and evaluate risks according to the minimum standards of the WHO. CONCLUSION: A strong PV system is an important part of the overall medicine regulatory system and reflects on the stringency and competence of the regulatory bodies in regulating the market ensuring the safety and effectiveness of medications. National PV systems in the study countries needed strengthening. Greater attention to funding is needed to coordinate and sustain PV activities. Our study highlights a need for developing more systematic approaches to regularly monitoring and evaluating PV policy and practices
Effects of maternal suicidal ideation on child cognitive development: A longitudinal analysis
This study aimed to assess the association between suicidal ideation among mothers living with HIV in Zimbabwe and the cognitive development of their children. Participants were mother–child dyads recruited from two rural districts in Zimbabwe. Data were collected at baseline and 12 months follow-up. Suicidal ideation was assessed using item-10 from the Edinburgh postnatal depression scale. Mixed-effects linear regression was used to assess the association of child cognitive outcomes at follow-up (using the Mullen scales of early learning) with maternal suicidal ideation. Mothers with suicidal ideation at baseline (n = 171) tended to be younger, unmarried, experienced moderate to severe hunger, had elevated parental stress and depression symptoms compared with non-suicidal mothers (n = 391). At follow-up, emerging maternal suicidal ideation was associated with poorer child cognitive outcomes (adjusted mean difference − 6.1; 95% CI − 10.3 to − 1.8; p = 0.03). Suicidal ideation affects child cognitive development and should be addressed, particularly in HIV positive mothers
Fludarabine as a cost-effective adjuvant to enhance engraftment of human normal and malignant hematopoiesis in immunodeficient mice
There is still an unmet need for xenotransplantation models that efficiently recapitulate normal and malignant human hematopoiesis. Indeed, there are a number of strategies to generate humanized mice and specific protocols, including techniques to optimize the cytokine environment of recipient mice and drug alternatives or complementary to the standard conditioning regimens, that can be significantly modulated. Unfortunately, the high costs related to the use of sophisticated mouse models may limit the application of these models to studies that require an extensive experimental design. Here, using an affordable and convenient method, we demonstrate that the administration of fludarabine (FludaraTM) promotes the extensive and rapid engraftment of human normal hematopoiesis in immunodeficient mice. Quantification of human CD45+ cells in bone marrow revealed approximately a 102-fold increase in mice conditioned with irradiation plus fludarabine. Engrafted cells in the bone marrow included hematopoietic stem cells, as well as myeloid and lymphoid cells. Moreover, this model proved to be sufficient for robust reconstitution of malignant myeloid hematopoiesis, permitting primary acute myeloid leukemia cells to engraft as early as 8 weeks after the transplant. Overall, these results present a novel and affordable model for engraftment of human normal and malignant hematopoiesis in immunodeficient mice
Correcting India's Chronic Shortage of Drug Inspectors to Ensure the Production and Distribution of Safe, High-Quality Medicines.
BACKGROUND: Good drug regulation requires an effective system for monitoring and inspection of manufacturing and sales units. In India, despite widespread agreement on this principle, ongoing shortages of drug inspectors have been identified by national committees since 1975. The growth of India's pharmaceutical industry and its large export market makes the problem more acute. METHODS: The focus of this study is a case study of Maharashtra, which has 29% of India's manufacturing units and 38% of its medicines exports. India's regulations were reviewed, comparing international, national and state inspection norms with the actual number of inspectors and inspections. Twenty-six key informant interviews were conducted to ascertain the causes of the shortfall. RESULTS: In 2009-2010, 55% of the sanctioned posts of drug inspectors in Maharashtra were vacant. This resulted in a shortfall of 83%, based on the Mashelkar Committee's recommendations. Less than a quarter of the required inspections of manufacturing and sales units were undertaken. The Indian Drugs and Cosmetics Act and its Rules and Regulations make no provisions for drug inspectors and workforce planning norms, despite the growth and increasing complexity of India's pharmaceutical industry. CONCLUSION: The Maharashtra Food and Drug Administration (FDA) falls short of the Mashelkar Committee's recommended workforce planning norms. Legislation and political and operational support are required to produce needed changes
When Is Higher Neuroticism Protective Against Death? Findings From UK Biobank
We examined the association between neuroticism and mortality in a sample of 321,456 people from UK Biobank and explored the influence of self-rated health on this relationship. After adjustment for age and sex, a 1- SD increment in neuroticism was associated with a 6% increase in all-cause mortality (hazard ratio = 1.06, 95% confidence interval = [1.03, 1.09]). After adjustment for other covariates, and, in particular, self-rated health, higher neuroticism was associated with an 8% reduction in all-cause mortality (hazard ratio = 0.92, 95% confidence interval = [0.89, 0.95]), as well as with reductions in mortality from cancer, cardiovascular disease, and respiratory disease, but not external causes. Further analyses revealed that higher neuroticism was associated with lower mortality only in those people with fair or poor self-rated health, and that higher scores on a facet of neuroticism related to worry and vulnerability were associated with lower mortality. Research into associations between personality facets and mortality may elucidate mechanisms underlying neuroticism's covert protection against death
Effects of Maternal Suicidal Ideation on Child Cognitive Development: A Longitudinal Analysis.
This study aimed to assess the association between suicidal ideation among mothers living with HIV in Zimbabwe and the cognitive development of their children. Participants were mother-child dyads recruited from two rural districts in Zimbabwe. Data were collected at baseline and 12 months follow-up. Suicidal ideation was assessed using item-10 from the Edinburgh postnatal depression scale. Mixed-effects linear regression was used to assess the association of child cognitive outcomes at follow-up (using the Mullen scales of early learning) with maternal suicidal ideation. Mothers with suicidal ideation at baseline (n = 171) tended to be younger, unmarried, experienced moderate to severe hunger, had elevated parental stress and depression symptoms compared with non-suicidal mothers (n = 391). At follow-up, emerging maternal suicidal ideation was associated with poorer child cognitive outcomes (adjusted mean difference - 6.1; 95% CI - 10.3 to - 1.8; p = 0.03). Suicidal ideation affects child cognitive development and should be addressed, particularly in HIV positive mothers
Electrochemical synthesis of peroxomonophosphate using boron-doped diamond anodes
A new method for the synthesis of peroxomonophosphate, based on the use of boron-doped diamond electrodes, is described. The amount of oxidant electrogenerated depends on the characteristics of the supporting media (pH and solute concentration) and on the operating conditions (temperature and current density). Results show that the pH, between values of 1 and 5, does not influence either the electrosynthesis of peroxomonophosphate or the chemical stability of the oxidant generated. Conversely, low temperatures are required during the electrosynthesis process to minimize the thermal decomposition of peroxomonophosphate and to guarantee significant oxidant concentration. In addition, a marked influence of both the current density and the initial substrate is observed. This observation can be explained in terms of the contribution of hydroxyl radicals in the oxidation mechanisms that occur on diamond surfaces. In the assays carried out below the water oxidation potential, the generation of hydroxyl radicals did not take place. In these cases, peroxomonophosphate generation occurs through a direct electron transfer and, therefore, at these low current densities lower concentrations are obtained. On the other hand, at higher potentials both direct and hydroxyl radical-mediated mechanisms contribute to the oxidant generation and the process is more efficient. In the same way, the contribution of hydroxyl radicals may also help to explain the significant influence of the substrate concentration. Thus, the coexistence of both phosphate and hydroxyl radicals is required to ensure the generation of significant amounts of peroxomonophosphoric acid
A comparison of electrochemical degradation of phenol on boron doped diamond and lead dioxide anodes
This work compares two electrode materials used to mineralize phenol contained in waste waters. Two disks covered with either boron doped diamond (BDD) or PbO2 were used as anodes in a one compartment flow cell under the same hydrodynamic conditions. Efficiencies of galvanostatic electrolyses are compared on the basis of measurements of Total Organic Carbon (TOC) and Chemical Oxygen Demand (COD). Galvanostatic electrolyses were monitored by analysis of phenol and of its oxidation derivatives to evaluate the operating time needed for complete elimination of toxic aromatics. The experimental current efficiency is close to the theoretical value for the BDD electrode. Other parameters being equal, phenol species disappeared at the same rate using the two electrode materials but the BDD anode showed better efficiency to eliminate TOC and COD. Moreover, during the electrolysis less intermediates are formed with BDD compared to PbO2 whatever the current density. A comparison of energy consumption is given based on the criterion of 99% removal of aromatic compounds
Free energy for parameterized Polyakov loops in SU(2) and SU(3) lattice gauge theory
We present a study of the free energy of parameterized Polyakov loops P in
SU(2) and SU(3) lattice gauge theory as a function of the parameters that
characterize P. We explore temperatures below and above the deconfinement
transition, and for our highest temperatures T > 5 T_c we compare the free
energy to perturbative results.Comment: Minor changes. Final version to appear in JHE
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