Comparison of corneal endothelial changes following phacoemulsification in diabetic and non-diabetic patients

Purpose:To study corneal endothelial changes post phacoemulsification in diabetic and non-diabetic patients.Methods:A comparative, prospective, observational study was conducted on 100 diabetic and 100 non-diabetics who underwent phacoemulsification. All patients were operated by the same surgeon by using the phaco chop technique to exclude any surgeon-related bias. Endothelial cell count, CCT, and coefficient of variance (CV) were measured with a specular microscope along with BCVA preoperatively and at 1 week, 4 weeks, and 3 months postoperatively. For statistical analysis, data were analyzed by using SPSS (version 27.0; SPSS Inc., Chicago, IL, USA). Data were summarized as mean and standard deviation for numerical variables and count and percentages for categorical variables. Chi square test, independent sample T test, and paired T test were used to compare the data. P ≤ 0.05 was considered statistically significant.Results:Postoperatively at 1 week, 4-week, and 3 months follow-up intervals, the mean endothelial cell count and coefficient of variance were significantly higher, and the mean percentage of hexagonal cells was significantly lower in non diabetic as compared to the diabetic group. A significant difference in mean central corneal thickness of the two groups was observed at 1-week and 4-weeks postoperative intervals; at both these intervals, the mean value was significantly higher in non diabetic as compared to the non-diabetic group. However, at 3-months post-operative interval, the difference between the two groups was not significant statistically. Mean BCVA values were significantly higher in diabetic as compared to the diabetic group at all three follow-up intervals.Conclusion:The findings of the present study show that endothelial cell characteristics are adversely affected in diabetic eyes as compared to non-diabetic patients undergoing phacoemulsification; this might also have an effect on the visual outcomes.     

Intestinal double-positive CD4+CD8+ T cells of neonatal rhesus macaques are proliferating, activated memory cells and primary targets for SIVMAC251 infection

Peripheral blood and thymic double-positive (DP) CD4(+)CD8(+) T cells from neonates have been described earlier, but the function and immunophenotypic characteristics of other tissue-derived DP T cells are not clearly understood. Here, we demonstrate the functional and immunophenotypic characteristics of DP cells in 6 different tissues, including thymus from normal neonatal rhesus macaques (Macaca mulatta) between 0 and 21 days of age. In general, intestinal DP T cells of neonates have higher percentages of memory markers (CD28(+)CD95(+)CD45RA(low)CD62L(low)) and proliferation compared with single-positive (SP) CD4(+) and CD8(+) T cells. In addition, percentages of DP T cells increase and CD62L expression decreases as animals mature, suggesting that DP cells mature and proliferate with maturity and/or antigen exposure. Consistent with this, intestinal DP T cells in neonates express higher levels of CCR5 and are the primary targets in simian immunodeficiency virus (SIV) infection. Finally, DP T cells produce higher levels of cytokine in response to mitogen stimulation compared with SP CD4(+) or CD8(+) T cells. Collectively, these findings demonstrate that intestinal DP T cells of neonates are proliferating, activated memory cells and are likely involved in regulating immune responses, in contrast to immature DP T cells in the thymus.     

Lactulose improves cognitive functions and health-related quality of life in patients with cirrhosis who have minimal hepatic encephalopathy

Minimal hepatic encephalopathy (MHE) has a negative effect on patients' daily functioning. Thus far, no study has investigated the effect of treatment-related improvement in cognitive functions on health-related quality of life (HRQOL). We measured psychometric performance by number and figure connection tests parts A and B, picture completion, and block design tests and HRQOL by the Sickness Impact Profile (SIP) of 90 patients with cirrhosis on inclusion into the study and 3 months later. A Z score less than -2 on the neuropsychological (NP) tests was considered abnormal. Sixty-one (67.7%) patients had MHE. They were randomly assigned in a 1:1 ratio to receive treatment (lactulose) for 3 months (n=31) or no treatment (n=30) in a nonblinded design. The mean number of abnormal NP tests decreased significantly in patients in the treated group (baseline, 2.74 [95% CI 2.40-3.08]; after 3 months, .75 [95% CI .36-1.16]) compared with patients in the untreated group (baseline, 2.47 [95% CI 2.19-2.74]; after 3 months, 2.55 [95% CI 2.16-2.94]); multivariate analysis of variance (MANOVA) for time and treatment, P=0.001. The mean total SIP score improved among patients in the treated group (baseline, 10.39 [95% CI 9.36-11.43]; after 3 months, 3.77 [95% CI 2.52-5.02]) compared with patients in the untreated group (baseline, 10.36 [95% CI 8.98-11.73]; after 3 months, 10.39 [95% CI 8.36-12.42]); MANOVA for time and treatment, P=0.002. Improvement in HRQOL was related to the improvement in psychometry. CONCLUSION: Treatment with lactulose improves both cognitive function and HRQOL in patients with cirrhosis who have MHE.     

Deciphering arterial identity through gene expression, genetics, and chemical biology

PURPOSE OF REVIEW: The present review presents a current view of vascular development, with a focus on the factors contributing to the establishment of arterial-venous identity and the potential of chemical biology for providing new insights into this field. RECENT FINDINGS: Genetics and gene expression studies have begun to define the complex network of molecular pathways that govern the formation of the embryonic vasculature, but these approaches have limited ability to spatially and temporally manipulate gene expression and function. Recently, the power of chemical biology, combined with model systems like zebrafish, has enabled discovery of additional contributors to vascular development and has provided a means of manipulating gene function with enhanced spatial and temporal control. SUMMARY: The molecular pathways directing arterial-venous specification during embryogenesis are relevant for understanding the causes of human arteriovenous malformations, tumor angiogenesis, and diabetic retinopathy. Through the complementary strengths of genetics and chemical biology, it is hoped that novel therapeutic approaches for these conditions will emerge.     

Induction of Immune Tolerance to FIX Following Muscular AAV Gene Transfer Is AAV-dose/FIX-level Dependent

Direct intramuscular injection (IM) of adeno-associated virus (AAV) has been proven a safe and potentially efficient procedure for gene therapy of many genetic diseases including hemophilia B. It is, however, contentious whether high antigen level induces tolerance or immunity to coagulation factor IX (FIX) following IM of AAV. We recently reported induction of FIX-specific immune tolerance by IM of AAV serotype one (AAV1) vector in mice. We hypothesize that the expression of high levels of FIX is critical to induction of FIX tolerance. In this study, we investigated the correlation among AAV dose, FIX expression, and tolerance induction. We observed that induction of immune tolerance or immunity to FIX was dependent on the dose of AAV1–human FIX (hFIX) given and the level of FIX antigen expressed in both normal and hemophilia mice. We then defined the minimum AAV1–hFIX dose and the lowest level of FIX needed for FIX tolerance. Different from hepatic AAV–hFIX gene transfer, we found that FIX tolerance induced by IM of AAV1 was not driven by regulatory T cells. These results provided further insight into the mechanism(s) of FIX tolerance, contributing to development of hemophilia gene therapy, and optimization of FIX tolerance induction protocols.     

Pharmacological cyclin dependent kinase inhibitors: Implications for colorectal cancer

Colorectal cancer accounts for a significant proportion of cancer deaths worldwide. The need to develop more chemotherapeutic agents to combat this disease is critical. Cyclin dependent kinases(CDKs), along with its binding partner cyclins, serve to control the growth of cells through the cell cycle. A new class of drugs, termed CDK inhibitors, has been studied in preclinical and now clinical trials. These inhibitors are believed to act as an anti-cancer drug by blocking CDKs to block the uncontrolled cellular proliferation that is hallmark of cancers like colorectal cancer. CDK article provides overview of the emerging drug class of CDK inhibitors and provides a list of ones that are currently in clinical trials.     

Probing chelation motifs in HIV integrase inhibitors

A series of HIV integrase (HIV-1 IN) inhibitors were synthesized to evaluate the role of the metal-binding group (MBG) in this class of metalloenzyme inhibitors. A total of 21 different raltegravir-chelator derivative (RCD) compounds were prepared that differed only in the nature of the MBG. These IN strand-transfer inhibitors (INSTIs) were evaluated in vitro in cell-free enzyme activity assays, and the in vitro results were further validated in cell culture experiments. All of the active compounds showed selective inhibition of the strand-transfer reaction over 3'-processing, suggesting a common mode of action with raltegravir. The results of the in vitro activity suggest that the nature of the MBG donor atoms, the overall MBG structure, and the specific arrangement of the MBG donor atom triad are essential for obtaining maximal HIV-1 IN inhibition. At least two compounds (RCD-4, RCD-5) containing a hydroxypyrone MBG were found to display superior strand-transfer inhibition when compared to an abbreviated analogue of raltegravir (RCD-1). By isolating and examining the role of the MBG in a series of INSTIs, we have identified a scaffold (hydroxypyrones) that may provide access to a unique class of HIV-1 IN inhibitors, and may help overcome rising raltegravir resistance.     

Measuring quality of life in aphasia: Results from two scales

Background: Although aphasia affects quality of life (QoL), the impact within specific domains (e.g., psychosocial, communication) is poorly understood. Moreover, the complex and multidimensional nature of QoL renders it difficult to measure accurately using a single global scale.

Aims: Using two recently developed QoL scales, the Stroke and Aphasia Quality of Life Scale‐39, (SAQOL; Hilari, Byng, Lamping, & Smith, 2003a Hilari, K., Byng, S., Lamping, D. L. and Smith, S. C. 2003a. Stroke and Quality of Life Scale‐39 (SAQOL‐39): Evaluation of acceptability, reliability and validity.. Stroke, 34: 1944–1950. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) and the American Speech Language Hearing Association's Quality of Communication Life Scale (QCL; Paul et al., 2004 Paul, D. R., Frattali, C. M., Holland, A. L., Thompson, C. K., Caperton, C. J. and Slater, S. C. 2004. Quality of Communication Life Scale, Rockville, MD: The American Speech‐Language‐Hearing Association.  [Google Scholar]), this study aimed to document the domains of QoL that were most affected for participants with aphasia compared to control participants, as well as to determine the relationship between the two scales, their sub‐domains, and linguistic variables in aphasia.

Methods & Procedures: The two scales were administered to a group of 19 participants with aphasia (14 male, 5 female), ages ranging from 27 to 79 years, and 19 age‐ and gender‐matched control participants. Various types and severity of aphasia were represented in the aphasia group. The performances of aphasia and control groups were compared, and correlation analyses examined the relationship between the two scales and their sub‐domains in the aphasia group only.

Outcomes & Results: Compared to control participants, QoL was lower in participants with aphasia, with the communication sub‐domain of SAQOL and socialisation/activities sub‐domain of QCL being the most affected areas of functioning. Between the two scales, the communication sub‐domain of SAQOL correlated with the socialisation/activities sub‐domain and the QCL mean. Moreover, linguistic variables correlated strongly with psychosocial, communication and socialisation/activities sub‐domains of QoL.

Conclusions: Measuring QoL using the SAQOL and the QCL captures different but equally important aspects of experiences of living with aphasia. When interpreted together, they provide a holistic picture of functioning in aphasia that includes broad overviews of QoL from the SAQOL and a finer‐grained analysis of communication impairments on QoL from the QCL.     

Coincidental loss of DOCK8 function in NLRP10-deficient and C3H/HeJ mice results in defective dendritic cell migration

Dendritic cells (DCs) are the primary leukocytes responsible for priming T cells. To find and activate naïve T cells, DCs must migrate to lymph nodes, yet the cellular programs responsible for this key step remain unclear. DC migration to lymph nodes and the subsequent T-cell response are disrupted in a mouse we recently described lacking the NOD-like receptor NLRP10 (NLR family, pyrin domain containing 10); however, the mechanism by which this pattern recognition receptor governs DC migration remained unknown. Using a proteomic approach, we discovered that DCs from Nlrp10 knockout mice lack the guanine nucleotide exchange factor DOCK8 (dedicator of cytokinesis 8), which regulates cytoskeleton dynamics in multiple leukocyte populations; in humans, loss-of-function mutations in Dock8 result in severe immunodeficiency. Surprisingly, Nlrp10 knockout mice crossed to other backgrounds had normal DOCK8 expression. This suggested that the original Nlrp10 knockout strain harbored an unexpected mutation in Dock8, which was confirmed using whole-exome sequencing. Consistent with our original report, NLRP3 inflammasome activation remained unaltered in NLRP10-deficient DCs even after restoring DOCK8 function; however, these DCs recovered the ability to migrate. Isolated loss of DOCK8 via targeted deletion confirmed its absolute requirement for DC migration. Because mutations in Dock genes have been discovered in other mouse lines, we analyzed the diversity of Dock8 across different murine strains and found that C3H/HeJ mice also harbor a Dock8 mutation that partially impairs DC migration. We conclude that DOCK8 is an important regulator of DC migration during an immune response and is prone to mutations that disrupt its crucial function.Dendritic cells (DCs) are crucial for the initiation of an adaptive immune response. Upon acquiring antigens in the periphery, DCs undergo a maturation process that includes antigen processing, cytokine production, and up-regulation of costimulatory molecules. A mature DC must then migrate from peripheral tissues to draining lymph nodes (LNs) to fulfill its role as an antigen-presenting cell that primes naïve T cells (1). Although the signals that induce this maturation process are now well-established (1), relatively little is understood about DC migration aside from the primary chemotactic cue provided by CCR7 that guides DCs to the LN (2, 3).We recently described a genetically modified NLRP10 (NLR family, pyrin domain containing 10) knockout strain in which this migration step was disrupted while leaving the remainder of the DC maturation program, including CCR7 expression, intact (4). NLRP10 is the only NOD-like receptor (NLR) without a leucine-rich repeat domain, the putative pathogen-associated molecular pattern (PAMP)–binding domain. It has been proposed to both positively and negatively regulate other NLRs, such as NOD1 and NLRP3, respectively (5, 6). Although we found that NLRP3 inflammasome activation was unaltered in the absence of NLRP10, we discovered that Nlrp10^−/− mice could not mount a productive T- or B-cell immune response due to a DC-intrinsic failure to emigrate out of inflamed tissues (4, 7).To understand the mechanism by which NLRP10 governs DC migration, we used an expression proteomic approach to identify molecules with altered expression in DCs generated from the Nlrp10^−/− strain and discovered a profound reduction in DOCK8 (dedicator of cytokinesis 8). DOCK8 is a guanine nucleotide exchange factor (GEF) that has two functional domains, DOCK homology region (DHR) 1 and DHR2 (8). In murine DCs, the DHR2 domain has been implicated in regulating the Rho GTPase CDC42 (cell division control protein 42 homolog), which in turn maintains cell polarity of mature DCs during migration (9, 10). Furthermore, mice harboring inactivating mutations in Dock8 lack marginal zone B-cell development, long-term antibody production following immunization, and memory CD8⁺ T-cell responses to viral infections (11, 12). In humans, inactivating mutations in Dock8 were recently identified as the primary genetic cause underlying autosomal recessive hyper-IgE syndrome (13). This syndrome presents with eczema, recurrent infections of the skin and respiratory tract, increased serum IgE, eosinophilia, recurrent fungal and viral infections, extensive food and environmental allergies, and, in certain patients, squamous cell dysplasia and carcinomas (14).Given that DOCK8 regulates a wide array of immunologic processes in mouse and human, we sought to understand how NLRP10 regulates DOCK8. To our surprise, we discovered that loss of DOCK8 in the Nlrp10^−/− strain was secondary to a point mutation within the Dock8 gene itself. In this study, we demonstrate that restoring DOCK8 function in the Nlrp10^−/− strain leads to normal DC migration in vivo. We further show that deletion of Dock8, as well as spontaneous mutation of Dock8 in another inbred strain of mice, results in defective DC migration and, depending on the degree of impaired migration, also abrogates CD4⁺ T-cell activation.