62 research outputs found

    Post occupancy evaluation of thermal comfort and indoor air quality of office spaces in a tropical green campus building

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    Purpose: As suggested in many previous studies, good thermal comfort and indoor air quality (IAQ) played a significant role in ensuring human comfort, health and productivity in buildings. Hence, this study aims to evaluate the thermal comfort and IAQ conditions of open-plan office areas within a green-certified campus building through a post occupancy evaluation. Design/methodology/approach: Using the field measurement method, environmental dataloggers were positioned at three office areas during office hours to measure the levels of thermal comfort parameters, CO2 concentrations and the supply air rates. At the same time, questionnaires were distributed to the available office staff to obtain their perception of the indoor environment. The findings were then compared with the recommended environmental comfort ranges and used to calculate the thermal comfort indices. Findings: Results show that the physical parameters were generally within acceptable ranges of a local guideline. The neutral temperature based on the actual mean vote at these areas was 23.9°C, which is slightly lower than the predicted thermal neutrality of 25.2°C. From the surveyed findings, about 81% of the occupants found their thermal environment comfortable with high adaptation rates. A preference for cooler environments was found among the workers. Meanwhile, the air quality was perceived to be clean by a majority of the respondents, and the mean ventilation rate per person was identified to be sufficient. Research limitations/implications: This study focussed on the thermal environment and air quality at selected office spaces only. More work should be carried out in other regularly occupied workplaces and study areas of the green educational building to allow a more thorough analysis of the indoor air conditions. Practical implications: This paper highlights on the thermal comfort and air quality conditions of the air-conditioned office spaces in a green-certified campus building and is intended to assist the building services engineers in effective air conditioning control. The findings reported are useful for thermal comfort, IAQ and subsequently energy efficiency improvements in such building type where adjustments on the air temperature set-point can be considered according to the actual requirements. This study will be extended to other green campus spaces for a more exhaustive analysis of the indoor environment. Originality/value: There is limited information pertaining to the environmental comfort levels in offices of green campus in the tropics. This study is, therefore, one of the earliest attempts to directly explore the thermal comfort and IAQ conditions in such workplace using both on-site physical measurement and questionnaire survey

    Differential Expression of Alpha 4 Integrins on Effector Memory T Helper Cells during Bordetella Infections. Delayed Responses in Bordetella pertussis

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    Bordetella pertussis (B. pertussis) is the causative agent of whooping cough, a respiratory disease that is reemerging worldwide. Mechanisms of selective lymphocyte trafficking to the airways are likely to be critical in the immune response to this pathogen. We compared murine infection by B. pertussis, B. parapertussis, and a pertussis toxin-deleted B. pertussis mutant (BpΔPTX) to test the hypothesis that effector memory T-helper cells (emTh) display an altered pattern of trafficking receptor expression in B. pertussis infection due to a defect in imprinting. Increased cell recruitment to the lungs at 5 days post infection (p.i.) with B. parapertussis, and to a lesser extent with BpΔPTX, coincided with an increased frequency of circulating emTh cells expressing the mucosal-associated trafficking receptors α4β7 and α4β1 while a reduced population of these cells was observed in B. pertussis infection. These cells were highly evident in the blood and lungs in B. pertussis infection only at 25 days p.i. when B. parapertussis and BpΔPTX infections were resolved. Although at 5 days p.i., an equally high percentage of lung dendritic cells (DCs) from all infections expressed maturation markers, this expression persisted only in B. pertussis infection at 25 days p.i. Furthermore, at 5 days p.i with B. pertussis, lung DCs migration to draining lymph nodes may be compromised as evidenced by decreased frequency of CCR7+ DCs, inhibited CCR7-mediated in vitro migration, and fewer DCs in lung draining lymph nodes. Lastly, a reduced frequency of allogeneic CD4+ cells expressing α4β1 was detected following co-culture with lung DCs from B. pertussis-infected mice, suggesting a defect in DC imprinting in comparison to the other infection groups. The findings in this study suggest that B. pertussis may interfere with imprinting of lung-associated trafficking receptors on T lymphocytes leading to extended survival in the host and a prolonged course of disease

    Discovery of a Non-Peptidic Inhibitor of West Nile Virus NS3 Protease by High-Throughput Docking

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    An estimated 2.5 billion people are at risk of diseases caused by dengue and West Nile virus. As of today, there are neither vaccines to prevent nor drugs to cure the severe infections caused by these viruses. The NS3 protease is one of the most promising targets for drug development against West Nile virus because it is an essential enzyme for viral replication and because success has been demonstrated with the closely related hepatitis C virus protease. We have discovered a small molecule that inhibits the NS3 protease of West Nile virus by computer-aided high-throughput docking, and validated it using three experimental techniques. The inhibitor has potential to be developed to a drug candidate to combat West Nile virus infections

    Integrative Genome Comparison of Primary and Metastatic Melanomas

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    A cardinal feature of malignant melanoma is its metastatic propensity. An incomplete view of the genetic events driving metastatic progression has been a major barrier to rational development of effective therapeutics and prognostic diagnostics for melanoma patients. In this study, we conducted global genomic characterization of primary and metastatic melanomas to examine the genomic landscape associated with metastatic progression. In addition to uncovering three genomic subclasses of metastastic melanomas, we delineated 39 focal and recurrent regions of amplification and deletions, many of which encompassed resident genes that have not been implicated in cancer or metastasis. To identify progression-associated metastasis gene candidates, we applied a statistical approach, Integrative Genome Comparison (IGC), to define 32 genomic regions of interest that were significantly altered in metastatic relative to primary melanomas, encompassing 30 resident genes with statistically significant expression deregulation. Functional assays on a subset of these candidates, including MET, ASPM, AKAP9, IMP3, PRKCA, RPA3, and SCAP2, validated their pro-invasion activities in human melanoma cells. Validity of the IGC approach was further reinforced by tissue microarray analysis of Survivin showing significant increased protein expression in thick versus thin primary cutaneous melanomas, and a progression correlation with lymph node metastases. Together, these functional validation results and correlative analysis of human tissues support the thesis that integrated genomic and pathological analyses of staged melanomas provide a productive entry point for discovery of melanoma metastases genes

    HIV-1 Envelope Subregion Length Variation during Disease Progression

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    The V3 loop of the HIV-1 Env protein is the primary determinant of viral coreceptor usage, whereas the V1V2 loop region is thought to influence coreceptor binding and participate in shielding of neutralization-sensitive regions of the Env glycoprotein gp120 from antibody responses. The functional properties and antigenicity of V1V2 are influenced by changes in amino acid sequence, sequence length and patterns of N-linked glycosylation. However, how these polymorphisms relate to HIV pathogenesis is not fully understood. We examined 5185 HIV-1 gp120 nucleotide sequence fragments and clinical data from 154 individuals (152 were infected with HIV-1 Subtype B). Sequences were aligned, translated, manually edited and separated into V1V2, C2, V3, C3, V4, C4 and V5 subregions. V1-V5 and subregion lengths were calculated, and potential N-linked glycosylation sites (PNLGS) counted. Loop lengths and PNLGS were examined as a function of time since infection, CD4 count, viral load, and calendar year in cross-sectional and longitudinal analyses. V1V2 length and PNLGS increased significantly through chronic infection before declining in late-stage infection. In cross-sectional analyses, V1V2 length also increased by calendar year between 1984 and 2004 in subjects with early and mid-stage illness. Our observations suggest that there is little selection for loop length at the time of transmission; following infection, HIV-1 adapts to host immune responses through increased V1V2 length and/or addition of carbohydrate moieties at N-linked glycosylation sites. V1V2 shortening during early and late-stage infection may reflect ineffective host immunity. Transmission from donors with chronic illness may have caused the modest increase in V1V2 length observed during the course of the pandemic

    HIV-2 interaction with cell coreceptors: amino acids within the V1/V2 region of viral envelope are determinant for CCR8, CCR5 and CXCR4 usage

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    © 2014 Santos-Costa et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background: Human immunodeficiency virus 1 and 2 (HIV-1 and HIV-2) use cellular receptors in distinct ways. Besides a more promiscuous usage of coreceptors by HIV-2 and a more frequent detection of CD4-independent HIV-2 isolates, we have previously identified two HIV-2 isolates (HIV-2MIC97 and HIV-2MJC97) that do not use the two major HIV coreceptors: CCR5 and CXCR4. All these features suggest that in HIV-2 the Env glycoprotein subunits may have a different structural organization enabling distinct - although probably less efficient - interactions with cellular receptors. Results: By infectivity assays using GHOST cell line expressing CD4 and CCR8 and blocking experiments using CCR8-specific ligand, I-309, we show that efficient replication of HIV-2MIC97 and HIV-2MJC97 requires the presence of CCR8 at plasma cell membrane. Additionally, we disclosed the determinants of chemokine receptor usage at the molecular level, and deciphered the amino acids involved in the usage of CCR8 (R8 phenotype) and in the switch from CCR8 to CCR5 or to CCR5/CXCR4 usage (R5 or R5X4 phenotype). The data obtained from site-directed mutagenesis clearly indicates that the main genetic determinants of coreceptor tropism are located within the V1/V2 region of Env surface glycoprotein of these two viruses. Conclusions: We conclude that a viral population able to use CCR8 and unable to infect CCR5 or CXCR4-positive cells, may exist in some HIV-2 infected individuals during an undefined time period, in the course of the asymptomatic stage of infection. This suggests that in vivo alternate molecules might contribute to HIV infection of natural target cells, at least under certain circumstances. Furthermore we provide direct and unequivocal evidence that the usage of CCR8 and the switch from R8 to R5 or R5X4 phenotype is determined by amino acids located in the base and tip of V1 and V2 loops of HIV-2 Env surface glycoprotein.This work was supported by grants from: Fundação para a Ciência e Tecnologia (FCT; PPCDT/SAU-IMI/55726/2004); Fundação para a Ciência e Tecnologia and Ministério da Saúde de Portugal (VIH/SAU/0006/2011); and from Gilead Sciences Portugal (Programa Gilead Génese).info:eu-repo/semantics/publishedVersio

    Clinical significance of HIV-1 coreceptor usage

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    The identification of phenotypically distinct HIV-1 variants with different prevalence during the progression of the disease has been one of the earliest discoveries in HIV-1 biology, but its relevance to AIDS pathogenesis remains only partially understood. The physiological basis for the phenotypic variability of HIV-1 was elucidated with the discovery of distinct coreceptors employed by the virus to infect susceptible cells. The role of the viral phenotype in the variable clinical course and treatment outcome of HIV-1 infection has been extensively investigated over the past two decades. In this review, we summarize the major findings on the clinical significance of the HIV-1 coreceptor usage

    Single-cell analysis tools for drug discovery and development

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    The genetic, functional or compositional heterogeneity of healthy and diseased tissues presents major challenges in drug discovery and development. Such heterogeneity hinders the design of accurate disease models and can confound the interpretation of biomarker levels and of patient responses to specific therapies. The complex nature of virtually all tissues has motivated the development of tools for single-cell genomic, transcriptomic and multiplex proteomic analyses. Here, we review these tools and assess their advantages and limitations. Emerging applications of single cell analysis tools in drug discovery and development, particularly in the field of oncology, are discussed

    The global distribution of lymphatic filariasis, 2000–18: a geospatial analysis

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    Background Lymphatic filariasis is a neglected tropical disease that can cause permanent disability through disruption of the lymphatic system. This disease is caused by parasitic filarial worms that are transmitted by mosquitos. Mass drug administration (MDA) of antihelmintics is recommended by WHO to eliminate lymphatic filariasis as a public health problem. This study aims to produce the first geospatial estimates of the global prevalence of lymphatic filariasis infection over time, to quantify progress towards elimination, and to identify geographical variation in distribution of infection. Methods A global dataset of georeferenced surveyed locations was used to model annual 2000–18 lymphatic filariasis prevalence for 73 current or previously endemic countries. We applied Bayesian model-based geostatistics and time series methods to generate spatially continuous estimates of global all-age 2000–18 prevalence of lymphatic filariasis infection mapped at a resolution of 5 km2 and aggregated to estimate total number of individuals infected. Findings We used 14 927 datapoints to fit the geospatial models. An estimated 199 million total individuals (95% uncertainty interval 174–234 million) worldwide were infected with lymphatic filariasis in 2000, with totals for WHO regions ranging from 3·1 million (1·6–5·7 million) in the region of the Americas to 107 million (91–134 million) in the South-East Asia region. By 2018, an estimated 51 million individuals (43–63 million) were infected. Broad declines in prevalence are observed globally, but focal areas in Africa and southeast Asia remain less likely to have attained infection prevalence thresholds proposed to achieve local elimination. Interpretation Although the prevalence of lymphatic filariasis infection has declined since 2000, MDA is still necessary across large populations in Africa and Asia. Our mapped estimates can be used to identify areas where the probability of meeting infection thresholds is low, and when coupled with large uncertainty in the predictions, indicate additional data collection or intervention might be warranted before MDA programmes cease

    QCD and strongly coupled gauge theories : challenges and perspectives

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    We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe
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