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Background: It is essential to assess the corneal thickness in diabetes patient. Introduction: diabetes mellitus is a major cause of blindness throughout the worldDiabetic retinopathy is the most importance given on day to day basics studies especially for ophthalmologist studied indicators in eye. However, functional oddities have been recognised in cornea too like changes in central corneal thickness. Objectives: 1. To estimate the central corneal thickness (CCT) of type 2 diabetes mellitus patients without diabetic retinopathy age/sex matched normal people. 2. To measure central corneal thickness (CCT) of type 2 diabetes mellitus patient with diabetic retinopathy with age/ sex matched normal person. Methods: This is a hospital based case control study. Expected Results: The central corneal thickness is more in type 2 diabetes patients than non-diabetic individual.

Objectives Current antiretroviral therapy can suppress HIV replication, increase CD4 count and result in increased lifespan. However, it cannot eradicate the virus due to the presence of latent provirus in cellular reservoirs, such as resting CD4+ T cells. Using combination latency-reversing agents to shock the virus out of latency for elimination through immune clearance or viral cytopathic effect is one of the most promising strategies for HIV eradication. Specifically, recent evidence shows that isoform-selective histone deacetylase inhibitors may be more effective than their non-selective counterparts. Therefore, identification and characterisation of new isoform-selective compounds are of prime importance. Here, we sought to determine the ability of two new isoform-targeted hydroxamic acid derivatives to reactivate HIV from latency. Methods We used cell lines and infected primary resting CD4+ T cells. These were treated with these compounds with HIV reactivation measured using fluorescence-activated cell sorting, Western blots and luciferase luminescence. Isoform selectivity and acetylation of the HIV promoter were measured by Western blotting and chromatic immunoprecipitation. Results and conclusions The two new hydroxamic acid derivatives, MC2625 and MC1742, potently reactivate HIV from latency. These compounds are isoform-selective histone deacetylate inhibitors that increase the levels of histone acetylation at the HIV promoter. In addition, they synergise effectively with the protein kinase C modulators bryostatin-1 and INDY, an inhibitor of the dual-specificity tyrosine phosphorylation regulated kinase 1A. We conclude that the combinations of new hydroxamic acid derivatives and bryostatin-1 or INDY could be a new tool for HIV reactivation in the cure efforts.

Despite the recent introduction of pneumococcal polysaccharide and conjugate vaccines, Streptococcus pneumoniae infection remains a leading cause of illness and death worldwide. In particular, infants in Papua New Guinea are at increased risk of severe pneumococcal pneumonia compared to infants in similar countries. We sought to determine if a novel genetic variant could explain this increased susceptibility. Whole exome sequencing revealed a single nucleotide variant (D308Y) in the gene encoding COQ6 (COQ6DY), a monooxygenase required for CoQ10 biosynthesis. We have utilized both a Saccharomyces cerevisiae model and a mouse model of COQ6DY to show that despite adequate production of CoQ10, this variant directly causes increased susceptibility to S. pneumoniae. This variant represents a previously unknown function of the CoQ10 biosynthetic complex that does not exert its effects through CoQ10 deficiency but rather through alterations of mitochondrial function and metabolism. These mitochondrial deficits in COQ6DY macrophages are sufficient to abrogate macrophage killing of S. pneumoniae and alter the coordination of the downstream immune response. In conclusion, we have identified a novel susceptibility allele to S. pneumoniae infection that exerts its effects via alterations in macrophage mitochondrial function. Supported by NIH (R21 AI142723), SLCH Children's Discovery Institute (PD-II-2018-742)

Current antiretroviral therapy (ART) for HIV/AIDS slows disease progression by reducing viral loads and increasing CD4 counts. Yet ART is not curative due to the persistence of CD4+ T-cell proviral reservoirs that chronically resupply active virus. Elimination of these reservoirs through the administration of synergistic combinations of latency reversing agents (LRAs), such as histone deacetylase (HDAC) inhibitors and protein kinase C (PKC) modulators, provides a promising strategy to reduce if not eradicate the viral reservoir. Here, we demonstrate that largazole and its analogues are isoform-targeted histone deacetylase inhibitors and potent LRAs. Significantly, these isoform-targeted HDAC inhibitors synergize with PKC modulators, namely bryostatin-1 analogues (bryologs). Implementation of this unprecedented LRA combination induces HIV-1 reactivation to unparalleled levels and avoids global T-cell activation within resting CD4+ T-cells.

The reason why HIV cannot be cured by current therapy is because of viral persistence in resting T cells. One approach to permanent HIV remission that has received less attention is the so-called “block and lock” approach. The idea behind this approach is that the virus could be permanently disabled in patients if viral genome or surrounding chromatin could be altered to silence the virus, thus enabling patients to stop therapy. In this work, we have identified splicing factor 3B subunit 1 (SF3B1) as a potential target for this approach. SF3B1 interacts with the viral protein Tat, which is critical for viral transcription. Inhibition of SF3B1 prevents HIV transcription and reactivation from latency. Since there are preclinical inhibitors for this protein, our findings could pave the way to silence HIV transcription, potentially leading to prolonged or permanent remission., The main obstacle to an HIV cure is the transcriptionally inert proviruses that persist in resting CD4 T cells and other reservoirs. None of the current approaches has significantly reduced the size of the viral reservoir. Hence, alternative approaches, such as permanent blocking of viral transcription, to achieve a sustained remission, need urgent attention. To identify cellular factors that may be important for this approach, we sought for host targets that when altered could block HIV transcription and reactivation. Here, we identified splicing factor 3B subunit 1 (SF3B1) as a critical HIV dependency factor required for viral replication. SF3B1 is a splicing factor involved in directing chromatin and nascent gene transcripts to appropriate splice sites. Inhibitors of SF3B1 are currently in development for cancer and have been found to be nontoxic to normal cells compared to malignant cells. Knockdown of SF3B1 abrogated HIV replication in all cell types tested. SF3B1 interacted with viral protein Tat in vitro and in vivo. Genetic or pharmacologic inhibition of SF3B1 prevented Tat-mediated HIV transcription and RNA polymerase II association with the HIV promoter. In addition, an inhibitor of SF3B1 prevented HIV reactivation from latency irrespective of the latency-reversing agent used. The data show that SF3B1 is involved in viral transcription and reactivation from latency and may serve as a therapeutic target in the HIV cure efforts.

To identify immune variants predisposing to severe pneumonia, we performed whole exome sequencing in a pediatric population highly susceptible to acute lower respiratory infections, identifying a candidate novel variant in the CoQ biosynthetic pathway. To evaluate the effect of this variant on immune function during bacterial pneumonia, we generated a mouse line using CRISPR-Cas9 that expresses the homologous variant in the enzyme COQ6. Interestingly, we found that the variant does not result in CoQ deficiency, as other known variants in biosynthetic proteins do, however intra-tracheal S. pneumoniae infection leads to increased bacteremia and mortality in mutant mice. Mechanistic studies show that mutant macrophages have reduced pneumococcal killing in vitro, showing an intrinsic defect in innate immune function conferred by the COQ6 mutation. Variant macrophages have decreased mitochondrial respiratory capacity both at baseline and following stimulation with LPS, as well as an inability to induce mitochondrial reactive oxygen species (mROS) in response to stimulation despite increased mROS at baseline. Thus, the novel variant in a CoQ biosynthetic enzyme leads to changes in macrophage mitochondrial function and an intrinsic inability to kill internalized bacteria. As alveolar macrophages are the first responders in the lung to bacterial challenge, the inability of these macrophages to mount a sufficient immune response leads to the observed increase in mortality following bacterial pneumonia. This work describes a novel susceptibility locus to severe childhood pneumonia, and also represents the first known pathogenic variant in a CoQ biosynthetic protein that does not cause pathology resulting from CoQ deficiency.

To identify immune variants predisposing to severe pneumonia, we performed whole exome sequencing in a pediatric population highly susceptible to acute lower respiratory infections, identifying a candidate novel variant in the ubiquinone (CoQ10) biosynthetic pathway. To evaluate the effect of this variant on immune function during bacterial pneumonia, we generated a mouse line using CRISPR-Cas9 that expresses the homologous aspartate to tyrosine variant in the enzyme COQ6. Intra-tracheal S. pneumoniae infection leads to increased bacteremia and mortality in mice homozygous for the variant despite similar numbers of immune cells in the lung. Mechanistic studies show that macrophages expressing the variant have decreased mitochondrial activity at the ubiquinone-dependent reduction of cytochrome c by complex III, as well as decreased maximum respiratory capacity in response to acute stimulation. Variant-expressing macrophages also exhibit impaired generation of mitochondrial reactive oxygen species (mROS) causing a direct, intrinsic defect in intracellular killing of internalized bacteria. Thus, the novel variant in CoQ10 biosynthesis leads to changes in macrophage mitochondria and an intrinsic inability to kill internalized bacteria. As alveolar macrophages are the first responders in the lung to bacterial challenge, the inability of these macrophages to mount a sufficient immune response can explain the observed increase in mortality following bacterial pneumonia. Because variants in CoQ10 biosynthesis can be supplemented with CoQ10, a readily available therapy may be able to correct this defect and improve survival in children with this variant

Summary The restriction factor SAMHD1 limits HIV-1 replication in noncycling cells. SIV and HIV-2 overcome this restriction via the accessory protein Vpx, which targets SAMHD1 for degradation through interactions with the host ubiquitin ligase adaptor DCAF1. However, the factors used by HIV-1 to replicate in macrophages, despite the presence of the restriction factor SAMHD1, are unknown. Using a yeast two-hybrid screen, we identified cyclin L2 as a DCAF1-interacting protein required for HIV-1 replication in macrophages. Knockdown of cyclin L2 results in severe attenuation of HIV-1 replication in macrophages but not cycling cells, and this effect is lost in the absence of SAMHD1. Cyclin L2 and SAMHD1 form a molecular complex that is partially dependent on the presence of DCAF1 and results in SAMHD1 degradation in a proteasome- and DCAF1-dependent manner. Therefore, cyclin L2-mediated control of SAMHD1 levels in macrophages supports HIV-1 replication.

Background Naturally occurring polyphenols found in food sources provide huge health benefits. Several polyphenolic compounds are implicated in the prevention of disease states, such as cancer. One of the mechanisms by which polyphenols exert their biological actions is by interfering in the protein kinase C (PKC) signaling pathways. PKC belongs to a superfamily of serine-threonine kinase and are primarily involved in phosphorylation of target proteins controlling activation and inhibition of many cellular processes directly or indirectly. Scope of review Despite the availability of substantial literature data on polyphenols' regulation of PKC, no comprehensive review article is currently available on this subject. This article reviews PKC-polyphenol interactions and its relevance to various disease states. In particular, salient features of polyphenols, PKC, interactions of naturally occurring polyphenols with PKC, and future perspective of research on this subject are discussed. Major conclusions Some polyphenols exert their antioxidant properties by regulating the transcription of the antioxidant enzyme genes through PKC signaling. Regulation of PKC by polyphenols is isoform dependent. The activation or inhibition of PKC by polyphenols has been found to be dependent on the presence of membrane, Ca2 + ion, cofactors, cell and tissue types etc. Two polyphenols, curcumin and resveratrol are in clinical trials for the treatment of colon cancer. General significance The fact that 74% of the cancer drugs are derived from natural sources, naturally occurring polyphenols or its simple analogs with improved bioavailability may have the potential to be cancer drugs in the future.