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Follicular CD8 + T cells (fCD8) mediate surveillance in lymph node (LN) germinal centers against lymphotropic infections and cancers, but the precise mechanisms by which these cells mediate immune control remain incompletely resolved. To address this, we investigated functionality, clonotypic compartmentalization, spatial localization, phenotypic characteristics, and transcriptional profiles of LN-resident virus-specific CD8 + T cells in persons who control HIV without medications. Antigen-induced proliferative and cytolytic potential consistently distinguished spontaneous controllers from noncontrollers. T cell receptor analysis revealed complete clonotypic overlap between peripheral and LN-resident HIV-specific CD8 + T cells. Transcriptional analysis of LN CD8 + T cells revealed gene signatures of inflammatory chemotaxis and antigen-induced effector function. In HIV controllers, the cytotoxic effectors perforin and granzyme B were elevated among virus-specific CXCR5 + fCD8s proximate to foci of HIV RNA within germinal centers. These results provide evidence consistent with cytolytic control of lymphotropic infection supported by inflammatory recruitment, antigen-specific proliferation, and cytotoxicity of fCD8s.

A novel Schiff base compound named as phenylmethanaminium (E)-4-((benzylimino)methyl)benzoate C7H10N+. C15H12NO2- (A) is synthesized by the chemical reaction of benzylamine and 4-carboxybenzaldehyde in ethanol, and the structure of the titled compound is verified using the single-crystal X-ray diffraction technique. Structural investigation inferred that the crystal packing is mainly stabilized by N-H···O and comparatively weak C-H···O bonding between the cation and anion and further stabilized by weak C-H···π and C-O···π interactions. Hirshfeld surface analysis is employed to explore the noncovalent interactions that are responsible for crystal packing quantitatively. Furthermore, we have used state-of-the-art quantum chemical calculations to get comprehensive insights into the structure-optoelectronic property relationship for the entitled compound. The molecular geometry of compound A is optimized at the M06/6-311G* level of theory. The linear polarizability, third-order nonlinear optical (NLO) polarizability, total and partial density of states, and UV-visible spectrum are calculated through quantum chemical calculations. We believe that compound A is not only a new addition to crystallographic data but also possesses good optical and NLO properties for its potential use in lasers and frequency-converting applications.

Drilling into fractures and fissures in carbonate reservoirs with lateral pore pressure variations is a major challenge. Accurately predicting and managing fracture initiation and fracture closure pressure is not practically feasible in naturally fractured carbonate rocks. Local fracture closure pressure (FCP, minimum in situ stress) around fractures are much lower than the mean value of FCP for the area, as observed in the Al Shaheen field. Drilling operators are experiencing massive lost circulation resulting in potential formation damage; and cost overruns. To address these lost circulation instances, modern lost circulation pills must be implemented. Drilling through the natural fractures within parts of the Shuaiba limestone reservoir usually results in significant drilling fluid losses, up to 50 m3/h. Lateral pore pressure variation causes dynamic inflow conditions within the wellbore, which make plugging fractures difficult. In addressing these lost circulation challenges, various approaches were previously used, notably reducing the hydrostatic pressure of fluids column, utilizing lighter weight drilling fluids, reducing the penetration of fluids into fractures with the use of various lost circulation materials, and the use of thixotropic cement slurries and lightweight high-solids-content cement slurries. Conventional lost circulation treatments provided very limited success under these conditions. An engineered composite fiber-based lost circulation pill with an innovative blend of fibers and sized solids to bridge and plug thief zones has been developed to address these lost circulation challenges. This pill was designed to be pumped through either a dummy bottomhole assembly (BHA) or through bypass circulation ports above the BHA with total flow area of 1.571 in2. These pills have been successfully used to mitigate losses while drilling as well as to achieve an incremental equivalent static density up to 144 kg/m3 to drill and cement the section. An impermeable grid created by this system was able to withstand the additional pressures. As a result, all the wells treated with these pills in the field were successfully drilled and cemented. After establishing the field specific guidelines over 2 years, continuous success was replicated in other wells for all the operator's rigs in Qatar.

Emitters coupled to waveguides have emerged as ideal platforms to achieve strong light-matter interaction in recent experiments. Here, we study the decaying of an atom into one-dimensional guided photonic modes using the master equation approach.

Background Helicobacter pylori occupy a unique niche, located within the mucus layer lining the stomach, and attached to the apical surface of the gastric epithelium. As such, antibodies would be expected to play a major role in regulating infection and/or pathogenesis. However, experiments using antibody-deficient mice to study gastric helicobacter infection have yielded inconsistent results, although some pointed toward antibodies increasing colonization levels and decreasing gastritis severity. The variability in these studies is possibly due to their use of nonmatched wild-type controls. This current study presents the first evaluation of the role of antibodies in H pylori infection by comparing antibody-deficient mice with matched wild-type siblings. Methods Matched wild-type and antibody-deficient μMT mice were generated by heterozygous crossings. In two separate experiments, appropriately genotyped sibling littermates were infected with H pylori for 4 months and then sera and stomachs were collected. Results There was no difference in H pylori colonization levels between infected μMT mice and sibling wild-type controls. Similarly, there was no significant difference in the severity of gastritis between these groups of mice, although there was a trend toward less severe gastritis in μMT mice which was supported by a significantly lower IFNγ (Th1) gastric cytokine response. Conclusions Comparing matched antibody-deficient and antibody-competent mice indicates that an antibody response does not influence H pylori colonization levels. Contrary to previous studies, these results suggest antibodies might have a minor pro-inflammatory effect by promoting gastric Th1 cytokines, although this did not translate to a significant effect on gastritis severity.

Summary Spontaneous control of HIV infection has been repeatedly linked to antiviral CD8+ T cells but is not always permanent. To address mechanisms of durable and aborted control of viremia, we evaluated immunologic and virologic parameters longitudinally among 34 HIV-infected subjects with differential outcomes. Despite sustained recognition of autologous virus, HIV-specific proliferative and cytolytic T cell effector functions became selectively and intrinsically impaired prior to aborted control. Longitudinal transcriptomic profiling of functionally impaired HIV-specific CD8+ T cells revealed altered expression of genes related to activation, cytokine-mediated signaling, and cell cycle regulation, including increased expression of the antiproliferative transcription factor KLF2 but not of genes associated with canonical exhaustion. Lymphoid HIV-specific CD8+ T cells also exhibited poor functionality during aborted control relative to durable control. Our results identify selective functional impairment of HIV-specific CD8+ T cells as prognostic of impending aborted HIV control, with implications for clinical monitoring and immunotherapeutic strategies.

Dengue virus (DENV) belonging to the family Flaviviridae consists of 4 serotypes (DEN-1, 2, 3 & 4) causing severe illnesses like dengue fever (DF), Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS). Dengue fever has become an emerging disease in Pakistan during the past 5-7 years with an increase in the number of cases every year since 2006. The current study aimed at identifying the serotypes of dengue virus involved in 2011 outbreak of Pakistan. Samples were collected from all provinces of Pakistan. Patients were confirmed in the hospital by antibody captured Enzyme linked immunosorbent assay (ELISA). These ELISA positive serum samples were inoculated on HeLa cell line to raise the viral titer of dengue virus and then RT-PCR was done for serotyping of dengue virus. Initially D1, D2 primers were tried for serotyping of dengue virus but poor results were obtained. Then serotype specific primers were designed having equal fragment length targeting NS1 gene. This approach was successful in serotyping of dengue virus from Pakistani population. On Real time RT-PCR, Dengue virus (DENV) was detected in 43.33% (n=26) patientsout of 60 analyzed samples. Among 26 positive cases, 76.9% (n=20) were children and 23.1% (n=6) were adultsand 46.1% (n=12) were male and 53.8 % (n=14) were females. ELISA results of26 PCR positive cases show that 53.8% (n=14) were positive for IgM, 15.4 % (n=4) were positive for IgG and 30.8 % (n=8) were positive for both IgG and IgM. In this study DEN-2 was detected in 13.3% (n=8) patients, DEN-3 was detected in 16.67% (n=10) patients and DEN-2 & DEN-3 coinfection was detected in 13.3% (n=8) patients. We did not detected DEN-1 & DEN-4 in 2011 outbreak of Pakistan in 60 analyzed samples. By this study we can conclude that DEN-2 and DEN-3 were the main serotypes involved in 2011 outbreaks in Pakistan.

Dengue virus infections are a major cause of mortality and morbidity in Southeast Asia South and Central America with rsquo deaths annually Two factors are accountable for the severe outcomes of Dengue Hemorrhagic Fever DHF one is the virulence of the virus and second is the cross reactivity of various dengue serotypes with the immune system of the host Rapid rise in the levels of various cytokines particularly Tumor Necrosis Factor alpha TNF alpha Interleukin IL Interleukin IL Interleukin IL have a major role in inducing distinctive clinical presentations of DHF These range from simple plasma leakage to hemorrhagic problems and even shock Another hallmark of DHF is the presence of cross reactive primary antibodies which produce an intense immune response in secondary infection resulting in immune mediated pathology seen in DHF There have been many attempts made in the past for the development of a suitable vaccine for dengue fever Vaccination using plasmid DNA against dengue fever is an active area of research In this review the role of different cells in the multiplication of dengue virus and viral interactions with the immune system have been discussed Special emphasis is given to the nature of DNA vaccines in general developmental efforts of a dengue fever vaccine

Over the last 60 years in the oil and gas industry, lost circulation has been the major nonproductive time (NPT) issue worldwide during well construction (12% of total NPT). According to industry figures, more than USD 2 billion are spent combating circulation loss each year. In the Rumaila field of Iraq, the NPT due to lost circulation is significant, estimated to be 46% of the total NPT recorded. The Rumaila oil field is a super-giant oil field in southern Iraq; the field is estimated to contain 17 billion barrels, which accounts for 12% of Iraq's oil reserves. In the Rumaila field, at least 45% of the wells experience severe to total circulation loss at depths of 450 to 650 m true vertical depth (TVD) while drilling in the karst facies of the Dammam formation. Numerous strategies, requiring up to 24 days of rig time or 15 cement plugs in some extreme cases, have been applied by different service companies without consistent results. This has resulted in higher operating costs and delayed production. Some of the identified reasons for the low success rate are poor wellbore characterization, weak assessment of the problem, and improper execution. The foundation of the proposed engineering and operational approach is the characterization of the wellbore with the caliper and formation image logs for better understanding of fractures and estimation of fracture volume. The approach also includes two cement slurry-type options—an increased slurry rheology with reduced density and a slurry with rapid gel strength development. The proposed approach is made complete with the engineered estimation of cement slurry volume, based on loss rate, and proper field deployment. Developed on the basis of previous experiences and optimization of hydrostatic pressure, cement slurry rheology, and gel strength development, the engineered lost circulation solution significantly improves the lost circulation control results. Extended evaluation of cement plug jobs with the engineered design and proper execution has proven the effective impact of the solution, curing losses during the drilling phase (

Over the last three decades, CPUs have continued to produce large performance improvements from one generation to the next. However, CPUs have recently hit a performance wall and need parallel computing to move forward. Parallel computing over the next decade will become increasingly defined by heterogeneous computing, involving the use of accelerators in addition to CPUs to get computational tasks done. In order to use an accelerator, software changes must be made. Regular x86-based compilers cannot compile code to run on accelerators without these needed changes. The amount of software change required varies depending upon the availability of and reliance upon software tools that increase performance and productivity. Writing software that leverages the best parallel computing hardware, adapts well to the rapid pace of hardware updates, and minimizes developer muscle is the industry’s goal. OpenCL is the standard around which developers are able to achieve parallel performance. OpenCL itself is too difficult to program to receive general adoptions, but productive high-performing software libraries are becoming increasingly popular and capable in delivering lasting value to user applications.