Receptor tyrosine kinases (RTKs) are co-deregulated in a majority of glioblastoma (GBM), the most common and most deadly brain tumor. We show that the RTKs MET, EGFR, and PDGFR regulate microRNA-134 ...(miR-134) in GBM. We find that miR-134 is downregulated in human tumors and cancer stem cells and that its expression inversely correlates with the activation of MET, EGFR, and PDGFR. We demonstrate that miR-134 inhibits cancer cell and stem-cell proliferation, survival, and xenograft growth, as well as cancer stem-cell self-renewal and stemness. We identify KRAS and STAT5B as targets of miR-134, and establish molecular and functional links between RTKs, miR-134, KRAS/STAT5B and malignancy in vitro and in vivo. We show that miR-134 induction is required for the anti-tumor effects of RTK inhibitors. We also uncover the molecular pathways through which RTKs regulate miR-134 expression and demonstrate the involvement of MAPK signaling and the KLF4 transcription factor. We therefore identify miR-134 as a novel RTK-regulated tumor-suppressive hub that mediates RTK and RTK-inhibitor effects on GBM malignancy by controlling KRAS and STAT5B.
The main limitations to umbilical cord blood (UCB) transplantation (UCBT) in adults are delayed engraftment, poor immunological reconstitution and high rates of non-relapse mortality (NRM). Double ...UCBT (DUCBT) has been used to circumvent the issue of low cell dose, but acute GVHD remains a significant problem. We describe our experience in 32 subjects, who underwent DUCBT after reduced-intensity conditioning with fludarabine/melphalan/antithymocyte globulin and who received sirolimus and tacrolimus to prevent acute GVHD. Engraftment of neutrophils occurred in all patients at a median of 21 days, and platelet engraftment occurred at a median of 42 days. Three subjects had grade II-IV acute GVHD (9.4%) and chronic GVHD occurred in four subjects (cumulative incidence 12.5%). No deaths were caused by GVHD and NRM at 100 days was 12.5%. At 2 years, NRM, PFS and OS were 34.4, 31.2 and 53.1%, respectively. As expected, immunologic reconstitution was slow, but PFS and OS were associated with reconstitution of CD4(+) and CD8(+) lymphocyte subsets, suggesting that recovery of adaptive immunity is required for the prevention of infection and relapse after transplantation. In summary, sirolimus and tacrolimus provide excellent GVHD prophylaxis in DUCBT, and this regimen is associated with low NRM after DUCBT.
Recent genome-wide studies found that patients with hypotonia, developmental delay, intellectual disability, congenital anomalies, characteristic facial dysmorphic features, and low cholesterol ...levels suffer from Kaufman oculocerebrofacial syndrome (KOS, also reported as blepharophimosis-ptosis-intellectual disability syndrome). The primary cause of KOS is autosomal recessive mutations in the gene UBE3B. However, to date, there are no studies that have determined the cellular or enzymatic function of UBE3B. Here, we report that UBE3B is a mitochondrion-associated protein with homologous to the E6-AP Cterminus (HECT) E3 ubiquitin ligase activity. Mutating the catalytic cysteine (C1036A) or deleting the entire HECT domain (amino acids 758–1068) results in loss of UBE3B's ubiquitylation activity. Knockdown of UBE3B in human cells induces changes in mitochondrial morphology and physiology, a decrease in mitochondrial volume, and a severe suppression of cellular proliferation. We also discovered that UBE3B interacts with calmodulin via its N-terminal isoleucine-glutamine (IQ) motif. Deletion of the IQ motif (amino acids 29–58) results in loss of calmodulin binding and a significant increase in the in vitro ubiquitylation activity of UBE3B. In addition, we found that changes in calcium levels in vitro disrupt the calmodulin-UBE3B interaction. These studies demonstrate that UBE3B is an E3 ubiquitin ligase and reveal that the enzyme is regulated by calmodulin. Furthermore, the modulation of UBE3B via calmodulin and calcium implicates a role for calcium signaling in mitochondrial protein ubiquitylation, protein turnover, and disease.
Screening and diagnostic tests provide an objective measure of cognitive performance and also aid in distinguishing mild cognitive impairment (MCI) from major neurocognitive disorder (MNCD). Further, ...when such tests are culturally and educationally unbiased, it strengthens their diagnostic utility. This study aimed to validate the Hindi version of Addenbrooke's Cognitive Examination III (ACE-III) in Indian older adults and compare its validity with the Hindi Mini-Mental State Examination (HMSE).
A sample of 412 consenting older adults visiting a memory clinic was recruited into the study. They were categorized into three groups: healthy controls (n=222), MCI (n=70), and MNCD (n=120). The complete clinical protocol was followed. Hindi ACE-III and HMSE were administered and were statistically analyzed.
The optimal cut-off values to detect MCI and MNCD with ACE-III were 71 and 62 (AUC: 0.849 and 0.884), respectively, which were slightly higher than with HMSE (AUC: 0.822, 0.861). Education- and age-stratified cut-offs were also computed.
Hindi ACE-III has good discriminating power at lower cut-offs than the standard scores in differentiating between MCI and MNCD.
The understanding of the correlation between structural and photoluminescence (PL) properties of self-assembled semiconductor quantum dots (QDs), particularly InGaAs QDs grown on (001) GaAs ...substrates, is crucial for both fundamental research and optoelectronic device applications. So far structural and PL properties have been probed from two different epitaxial layers, namely top-capped and buried layers respectively. Here, we report for the first time both structural and PL measurements from an uncapped layer of InGaAs QDs to correlate directly composition, strain and shape of QDs with the optical properties. Synchrotron X-ray scattering measurements show migration of In atom from the apex of QDs giving systematic reduction of height and enlargement of QDs base in the capping process. The optical transitions show systematic reduction in the energy of ground state and the first excited state transition lines with increase in capping but the energy of the second excited state line remain unchanged. We also found that the excitons are confined at the base region of these elliptically shaped QDs showing an interesting volume-dependent confinement energy scaling of 0.3 instead of 0.67 expected for spherical dots. The presented method will help us tuning the growth of QDs to achieve desired optical properties.
The ability of the endothelium to produce nitric oxide, which induces generation of cyclic guanosine monophosphate (cGMP) that activates cGMP-dependent protein kinase (PKG-I), in vascular smooth ...muscle cells (VSMCs), is essential for the maintenance of vascular homeostasis. Yet, disturbance of this nitric oxide/cGMP/PKG-I pathway has been shown to play an important role in many cardiovascular diseases. In the last two decades, in vitro and in vivo models of vascular injury have shown that PKG-I is suppressed following nitric oxide, cGMP, cytokine, and growth factor stimulation. The molecular basis for these changes in PKG-I expression is still poorly understood, and they are likely to be mediated by a number of processes, including changes in gene transcription, mRNA stability, protein synthesis, or protein degradation. Emerging studies have begun to define mechanisms responsible for changes in PKG-I expression and have identified cis- and trans-acting regulatory elements, with a plausible role being attributed to post-translational control of PKG-I protein levels. This review will focus mainly on recent advances in understanding of the regulation of PKG-I expression in VSMCs, with an emphasis on the physiological and pathological significance of PKG-I down-regulation in VSMCs in certain circumstances.
This experiment investigated the effects of dietary supplementation of single-strain probiotic (SSP) containing Bacillus subtilis 2 × 109 cfu/g and multi-strain probiotic (MSP) containing ...Lactobacillus acidophilus 3 × 107–108 cfu/g, Bacillus subtilis 3 × 107-108 cfu/g, and Saccharomyces cerevisiae 106–107 cells/g on ISA Brown layers' productive performance and egg quality traits for 26 to 51 wk. Eighty-four birds were reared in cages of an open-sided house. SSP was fed either at 0.375, 0.50, or 0.625 g/kg feed or MSP either at 0.75, 1.00, or 1.25 g/kg feed, and a control group were maintained. Each dietary treatment was replicated 6 times, having 2 birds each. Egg production increased linearly with dose increment in the MSP-fed birds. Both SSP and MSP caused an improvement in egg weight, egg mass, and FCR. Feed intake and body weight gain were not affected by probiotic feeding. At 37 wk, MSP-fed birds had a higher shell percentage, whereas the value was higher for both SSP and MSP at 49 wk. Shell thickness rose linearly by MSP at 37 wk and followed a similar trend at 49 wk along with SSP. Haugh unit also increased in both weeks with SSP and MSP. Due to MSP feeding, the predicted yolk index dose was 0.67g/kg at 37 wk and increased linearly at 49 wk. The yolk percent varied with doses of SSP and MSP, while albumen percent with MSP doses at 37 wk. In conclusion, MSP increased egg production, and both SSP and MSP positively influenced other laying performances and egg quality, notably shell and albumen quality.
The epidemiology of Mycoplasma pneumoniae (Mp) is poorly understood in India. The present study was conducted to identify the prevalence of Mp in a large set of patients with acute respiratory tract ...infections (ARI) in an Indian tertiary hospital. During 2015–2020, we tested throat swab specimens from patients with the clinical diagnosis of ARI (n = 1,098) by a real-time PCR and compared the demographic, clinical, laboratory, and outcome data of Mp-positive and Mp-negative patients. During the study period, 5% (55/1,098) of the tested samples were positive for Mp by PCR. School-aged children and young adults represented 36% (20/55) of the cases and 47.3% (26/55) of the cases were registered during the summer and monsoon. Among the Mp-positive patients, 61.8% (34/55) had underlying conditions; the most common were malignancy (n = 12; 21.8%) and hypertension (n = 6; 10.9%). Fever (98.2% versus 84.9%; P = 0.006), and pharyngitis (27.3% versus 16.3%; P = 0.034) were significantly common in the Mp-positive group than Mp-negative group. Among the Mp-positive group, 20% (11/55) of patients were admitted to an intensive care unit and a total of 7/55 (12.7%) patients received ventilatory support. The mortality in the Mp-positive cohort was 13.3%. The study provides baseline data regarding Mp prevalence and clinical characteristics. The application of molecular assays for diagnosing this pathogen among hospitalized patients with ARI could reduce inappropriate empirical antibiotic treatment and improve patient outcomes. Further large-scale studies are required to avoid the underdiagnosis of Mp infections in India and such studies should address some research gaps, such as macrolide resistance and molecular typing. IMPORTANCE M. pneumoniae (Mp) is a significant pathogen causing atypical pneumonia but by far these infections are underreported clinical entities in India. In the present study, we report the prevalence of Mp and describe the demographic and baseline clinical data of Mp-positive cases in an Indian tertiary care hospital. Our study may improve the clinician’s awareness of this important agent of respiratory infection therefore timely and accurate diagnostic tools can be applied for patient management decisions and outcomes.
Background. Overexpression of programmed death 1 (PD-1) receptor is thought to inhibit the effector T-cell response in human tuberculosis. However, the precise mechanism of such inhibition remains ...unclear. The present study addresses the role of PD-1 in dampening host T-cell function among patients with pulmonary tuberculosis. Methods. Expression of PD-1 and its ligands (PD-L1/L2) on T cells, B cells, and monocytes was evaluated by flow cytometry (FACS). In vitro stimulation of peripheral blood mononuclear cells in the presence of Mycobacterium tuberculosis antigens was performed with and without blocking PD-1, and intracellular cytokine production was measured by FACS. Results. We showed higher frequencies of T cells, monocytes, and B cells expressing PD-1 and its ligand(s) among patients with pulmonary tuberculosis. Infections with live M. tuberculosis upregulated PD-L1 expression on monocytes. In vitro PD-1 blocking rescued M. tuberculosis-specific interferon γ (IFN-γ)-producing T cells from undergoing apoptosis. The number of PD-1-expressing T cells decreased significantly during therapy and inversely correlated with IFN-γ-dominant T-cell response against M. tuberculosis. Conclusions. Manipulation of PD-1 signaling may restore the host T-cell response and thus may have therapeutic potential. PD-1 also may serve as a biomarker to monitor host immunity among patients with tuberculosis during therapy and vaccine studies.
PDF
