Cell death is an important mechanism to limit uncontrolled T-cell expansion during immune responses. Given the role of death-receptor adapter protein Fas-associated death domain (FADD) in apoptosis, ...it is intriguing that T-cell receptor (TCR)–induced proliferation is blocked in FADD-defective T cells. Necroptosis is an alternate form of death that can be induced by death receptors and is linked to autophagy. It requires the death domain-containing kinase RIP1 and, in certain instances, RIP3. FADD and its apoptotic partner, Caspase-8, have also been implicated in necroptosis. To accurately assess the role of FADD in mature T-cell proliferation and death, we generated a conditional T-cell–specific FADD knockout mouse strain. The T cells of these mice develop normally, but lack FADD at the mature stage. FADD-deficient T cells respond poorly to TCR triggering, exhibit slow cell cycle entry, and fail to expand over time. We find that programmed necrosis occurs during the late stage of normal T-cell proliferation and that this process is greatly amplified in FADD-deficient T cells. Inhibition of necroptosis using an inhibitor of RIP1 kinase activity rescues the FADD knockout proliferative defect. However, TCR-induced necroptosis did not appear to require autophagy or involve RIP3. Consistent with their defective CD8 T-cell response, these mice succumb to Toxoplasma gondii infection more readily than wild-type mice. We conclude that FADD constitutes a mechanism to keep TCR-induced programmed necrotic signaling in check during early phases of T-cell clonal expansion.
Rabies is a fatal zoonotic disease that requires fast, accurate diagnosis to prevent disease in an exposed individual. The current gold standard for post-mortem diagnosis of human and animal rabies ...is the direct fluorescent antibody (DFA) test. While the DFA test has proven sensitive and reliable, it requires high quality antibody conjugates, a skilled technician, a fluorescence microscope and diagnostic specimen of sufficient quality. The LN34 pan-lyssavirus real-time RT-PCR assay represents a strong candidate for rabies post-mortem diagnostics due to its ability to detect RNA across the diverse Lyssavirus genus, its high sensitivity, its potential for use with deteriorated tissues, and its simple, easy to implement design. Here, we present data from a multi-site evaluation of the LN34 assay in 14 laboratories. A total of 2,978 samples (1,049 DFA positive) from Africa, the Americas, Asia, Europe, and the Middle East were tested. The LN34 assay exhibited low variability in repeatability and reproducibility studies and was capable of detecting viral RNA in fresh, frozen, archived, deteriorated and formalin-fixed brain tissue. The LN34 assay displayed high diagnostic specificity (99.68%) and sensitivity (99.90%) when compared to the DFA test, and no DFA positive samples were negative by the LN34 assay. The LN34 assay produced definitive findings for 80 samples that were inconclusive or untestable by DFA; 29 were positive. Five samples were inconclusive by the LN34 assay, and only one sample was inconclusive by both tests. Furthermore, use of the LN34 assay led to the identification of one false negative and 11 false positive DFA results. Together, these results demonstrate the reliability and robustness of the LN34 assay and support a role for the LN34 assay in improving rabies diagnostics and surveillance.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Due to the current economic environment, many local and state health departments are faced with budget reductions. Health department administrators and public health laboratory (PHL) directors need ...to assess strategies to ensure that their PHLs can provide the same level of service with decreased funds. Exploratory case studies of interorganizational partnerships among local PHLs in California were conducted to determine the impact on local PHL testing services and capacity. Our findings suggest that interorganizational forms of cooperation among local PHLs can help bolster laboratory capacity by capturing economies of scale, leveraging scarce resources, and ensuring access to affordable, timely, and quality laboratory testing services. Interorganizational partnerships will help local and state public health departments continue to maintain a strong and robust laboratory system that supports their role in communicable disease surveillance.
Metagenomic next-generation sequencing (mNGS), the shotgun sequencing of RNA and DNA from clinical samples, has proved useful for broad-spectrum pathogen detection and the genomic surveillance of ...viral outbreaks. An additional target enrichment step is generally needed for high-sensitivity pathogen identification in low-titre infections, yet available methods using PCR or capture probes can be limited by high cost, narrow scope of detection, lengthy protocols and/or cross-contamination. Here, we developed metagenomic sequencing with spiked primer enrichment (MSSPE), a method for enriching targeted RNA viral sequences while simultaneously retaining metagenomic sensitivity for other pathogens. We evaluated MSSPE for 14 different viruses, yielding a median tenfold enrichment and mean 47% (±16%) increase in the breadth of genome coverage over mNGS alone. Virus detection using MSSPE arboviral or haemorrhagic fever viral panels was comparable in sensitivity to specific PCR, demonstrating 95% accuracy for the detection of Zika, Ebola, dengue, chikungunya and yellow fever viruses in plasma samples from infected patients. Notably, sequences from re-emerging and/or co-infecting viruses that have not been specifically targeted a priori, including Powassan and Usutu, were successfully enriched using MSSPE. MSSPE is simple, low cost, fast and deployable on either benchtop or portable nanopore sequencers, making this method directly applicable for diagnostic laboratory and field use.
TRAIL receptor (TRAIL-R) signaling has been implicated in inducing apoptosis in tumor cells, but little is understood about its physiological function. Here, we report the generation and ...characterization of
TRAIL-R
−/−
mice, which develop normal lymphocyte populations but possess enhanced innate immune responses.
TRAIL-R
−/−
mice exhibited increased clearance of murine cytomegalovirus that correlated with increased levels of IL-12, IFN-α, and IFN-γ. Stimulation of macrophages with
Mycobacterium and Toll-like receptor (TLR)-2, -3, and -4, but not TLR9, ligands resulted in high levels of TRAIL upregulation and enhanced cytokine production in
TRAIL-R
−/−
cells. The immediate-early TLR signaling events in
TRAIL-R
−/−
macrophages and dendritic cells are normal, but IκB-α homeostatic regulation and NF-κB activity at later time points is perturbed. These data suggest that TRAIL-R negatively regulates innate immune responses.
Background. California has 61 local health departments that are currently served by 37 local public health laboratories. These laboratories act as the first line of defense against health threats by ...providing community disease surveillance, food and environmental safety testing, newborn disease screening, identification of causal agents during an outbreak, and national disease screening for biological agents of warfare, resulting in a decreased burden on the health care system. In January 2009, the Little Hoover Commission released a report "First Year Checkup: Strategies for a Stronger Public Health Department" to address ways in which the California Department of Public Health can improve public health and safety. One of the five major recommendations made was for the California Department of Public Health to continue to provide leadership to strengthen the state's laboratory capacity by helping to facilitate consolidation of county public health laboratories into regional laboratories. Due to the California budget crisis and the shortage of public health laboratory directors qualified to run laboratories, regionalization has been proposed as a strategy to address resource constraints as well as to obtain economies of scale in the provision of laboratory services. However, there is resistance from a subset of county public health laboratory directors as well as county health officers to regionalize local public health laboratories. In addition, neither the California Department of Public Health nor the state has the legal authority or financial resources to enforce county public health laboratory regionalization. The rationale and the feasibility of implementing the Little Hoover Commission's recommendation need to be more thoroughly explored. Purpose. This dissertation research was conducted to incorporate the perspectives of county public health laboratory directors, county health officers, and state public health officials in order to assess whether reorganization of county public health laboratories is a feasible solution to bolster California's public health laboratory capacity. Methodology. Case studies of inter-organizational forms of cooperation among public health laboratories in California were conducted to assess necessary "factors of success" when engaging in an inter-organizational partnership between public health laboratories. Qualitative interviews were also conducted with public health laboratory directors, health officers, and state public health officials to assess (1) the feasibility of public health laboratories engaging in inter-organizational partnerships and (2) the impact that an inter-organizational partnership will have on addressing the state's insufficient PHL capacity. Lastly, policy options aimed at bolstering the state's laboratory capacity were proposed based on findings from the case studies and the interviews. Findings. Analysis of the data collected through the case studies and qualitative interviews with public health laboratory directors, county health officers and state public health officials suggests that an inter-organizational form of cooperation such as a regionalization effort of local county public health laboratories led by the state is not a feasible solution to help bolster laboratory capacity. However, a consolidation effort of public health laboratories led by county administrators and public health laboratory directors through a joint powers agreement is a potential solution for (1) ensuring affordable and continuous provision of public health laboratory testing services for all public health departments and (2) a short-term measure to address the shortage of board certified, doctoral level public health laboratory directors available to supervise laboratories located in rural counties. The three policy options that would be effective at addressing the state's insufficient laboratory capacity include (1) amend the state PHLD requirements, (2) promote locally driven PHL consolidation efforts through utilization of joint powers agreements and (3) provide state funding for PHL services in rural counties.
This paper evaluates the safety and acceptability of long-term
community-based use of misoprostol for management of postpartum
hemorrhage (PPH) in home-births, by comparing deliveries with and
...without misoprostol use in communities of Kigoma, Tanzania. We
administered a standardized survey instrument to women who delivered
between August 2004 and May 2007. 940 women completed questionnaires,
corresponding to 950 deliveries. Findings showed that the majority of
TBAs administered misoprostol at the correct time (76%). Receipt of
three or five tablets was most commonly reported (47% and 43%
respectively). Misoprostol users were significantly more likely to
experience shivering, high temperature, nausea, and vomiting after
delivery; adjustment for gynecological history and delivery
characteristics revealed no significant differences in experience of
symptoms. Misoprostol was highly acceptable to all women surveyed.
Misoprostol at the community level is a safe intervention (Afr J Reprod
Health 2009; 132:117-128).
This paper evaluates the safety and acceptability of long-term community-based use of misoprostol for management of postpartum hemorrhage (PPH) in home-births, by comparing deliveries with and ...without misoprostol use in communities of Kigoma, Tanzania. We administered a standardized survey instrument to women who delivered between August 2004 and May 2007. 940 women completed questionnaires, corresponding to 950 deliveries. Findings showed that the majority of TBAs administered misoprostol at the correct time (76%). Receipt of three or five tablets was most commonly reported (47% and 43% respectively). Misoprostol users were significantly more likely to experience shivering, high temperature, nausea, and vomiting after delivery; adjustment for gynecological history and delivery characteristics revealed no significant differences in experience of symptoms. Misoprostol was highly acceptable to all women surveyed. Misoprostol at the community level is a safe intervention. Disponibilité de misoprostol dans la communauté : est-il sans danger? Cet article évalue la sauveté et l'acceptabilité de l'emploi à long terme de misoprostol dans la communauté pour le traitement de l'hémorragie du post partum (HPP) dans les naissances à domicile, en comparant les accouchements avec et sans l'utilisation de misoprostol dans les communautés de Kigoma, Tanzamie. Nous avons administré un instrument d'enquête standardisé aux femmes qui ont accouché entre le mois d'août 2004 et mai 2007. 940 femmes ont rempli des questionnaires, ce qui correspondait à 950 accouchements. Les résultats ont montré que la majorité des sages-femmes traditionnelles (SFTs) ont administre misoprostol comme il faut (76%). Elles ont indiqué en général avoir reçu trois ou cinq comprimés (47% et 43% respectivement). Les utilisateurs de misoprostol avaient la possibilité de subir le frissonnement, la haute température, la nausée et le vomissement après l'accouchement ; l'ajustement pour l'histoire gynécologique et les caractéristiques de l'accouchement n'ont pas révélé des différences significatives quant aux symptómes. Misoprostol a été bien acceptable à toutes les femmes enquêtées. Misoprostol au niveau de la communauté est une intervention sans danger.
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