Validation of the modified Berlin questionnaire to identify patients at risk for the obstructive sleep apnoea syndrome

Background & Objectives: Awareness regarding obstructive sleep apnoea (OSA) among general public as well as practicing physicians is low in India. The present study was undertaken to test the utility of modified Berlin questionnaire for risk categorization of OSA in Indian setting. Methods: The modified Berlin questionnaire was administered in 180 middle aged adults (of 320 screened), of whom, 104 underwent overnight polysomnograhy, in a cross-sectional study at a tertiary care, referral center in north India. Questionnaire addressed the presence of frequency of snoring, wake time sleepiness, fatigue, obesity and hypertension. Subjects with persistent and frequent symptoms in any two of these three domains were considered in high risk category for obstructive sleep apnoea. Overnight polysomnograhy was performed to measure apnoea and hypopnoea index (AHI). Results: Questions about the symptoms demonstrated internal consistency (Cronbach alpha correlations 0.92-0.96). Of the 180 respondents to the screening questions, 80 were in the high risk and the rest were in low risk group. For 104 subjects who underwent polysomnograhy, risk grouping was useful in prediction of AHI. High risk category predicted an AHI > 5 with a sensitivity of 86 per cent, specificity of 95 per cent, positive and negative predictive values of 96 and 82 per cent respectively. These results were comparable to Berlin questionnaire study done in the western population for validation. Interpretation & Conclusion: On the basis of the findings of present study it is concluded that administration of modified Berlin questionnaire prior to a polysomnography study can identify high risk subjects and can thus avoid unnecessary polysomnography studies especially in resource-limited settings. To identify subjects at risk for OSA syndrome in general population, this questionnaire can be applied. However, the findings of the present study need to be confirmed further in a large number of subjects in a community-based setting

Second Thoughts about Kripke\u27s Rule-Following Argument

クリプキによる規則遵守の議論は、「形式意味」に関する共時的な「規則遵守」の問題と、使用者の「話者意味」に関する通時的な「意図遵守」の問題とを並列化しており、さらに、意味の「構成」と「正当化」との二つの側面から議論展開していることを指摘し、その区別に基づく四象限の関係性が、数学的規則の場合と感覚言語の場合とで異なること、および、懐疑的解決以後は別の関係性として一元化されるとの解釈を提示した。加えて、別の著作内での「私的な名付け」との関連性、および、記述の人称について考察を加えた

Inactivation of Chk2 and Mus81 Leads to Impaired Lymphocytes Development, Reduced Genomic Instability, and Suppression of Cancer

Chk2 is an effector kinase important for the activation of cell cycle checkpoints, p53, and apoptosis in response to DNA damage. Mus81 is required for the restart of stalled replication forks and for genomic integrity. Mus81Δex3-4/Δex3-4 mice have increased cancer susceptibility that is exacerbated by p53 inactivation. In this study, we demonstrate that Chk2 inactivation impairs the development of Mus81Δex3-4/Δex3-4 lymphoid cells in a cell-autonomous manner. Importantly, in contrast to its predicted tumor suppressor function, loss of Chk2 promotes mitotic catastrophe and cell death, and it results in suppressed oncogenic transformation and tumor development in Mus81Δex3-4/Δex3-4 background. Thus, our data indicate that an important role for Chk2 is maintaining lymphocyte development and that dual inactivation of Chk2 and Mus81 remarkably inhibits cancer

DNA topoisomerases participate in fragility of the oncogene RET

Fragile site breakage was previously shown to result in rearrangement of the RET oncogene, resembling the rearrangements found in thyroid cancer. Common fragile sites are specific regions of the genome with a high susceptibility to DNA breakage under conditions that partially inhibit DNA replication, and often coincide with genes deleted, amplified, or rearranged in cancer. While a substantial amount of work has been performed investigating DNA repair and cell cycle checkpoint proteins vital for maintaining stability at fragile sites, little is known about the initial events leading to DNA breakage at these sites. The purpose of this study was to investigate these initial events through the detection of aphidicolin (APH)-induced DNA breakage within the RET oncogene, in which 144 APHinduced DNA breakpoints were mapped on the nucleotide level in human thyroid cells within intron 11 of RET, the breakpoint cluster region found in patients. These breakpoints were located at or near DNA topoisomerase I and/or II predicted cleavage sites, as well as at DNA secondary structural features recognized and preferentially cleaved by DNA topoisomerases I and II. Co-treatment of thyroid cells with APH and the topoisomerase catalytic inhibitors, betulinic acid and merbarone, significantly decreased APH-induced fragile site breakage within RET intron 11 and within the common fragile site FRA3B. These data demonstrate that DNA topoisomerases I and II are involved in initiating APH-induced common fragile site breakage at RET, and may engage the recognition of DNA secondary structures formed during perturbed DNA replication

New insight into the effects of lead modulation on antioxidant defense mechanism and trace element concentration in rat bone

Risks of heavy metals-induced severe bone disorders generate interest to their toxicity. The present study was undertaken to monitor the biochemical and antioxidant status of bone of 30 and 80 days old male Wistar rats exposed to 5 week lead treatment. At the end of study, the rats were sacrificed, their long bone i.e. femur were excised, cleaned of soft tissue, minced and homogenized. Nucleic acid content, alkaline phosphatase, lipid peroxidation, catalase, glutathione S-transferase and superoxide dismutase were determined in bone. In both groups of treated animals lead treatment increased the production of malondialdehyde, while reducing activities of catalase, glutathione S-transferase and superoxide dismutase, indicating that it causes oxidative stress. Parallely with these effects lead significantly reduced the nucleic acid content and the activity of alkaline phosphatase, considered as biomarkers of osteoblast's function, conditions and development of bones. Moreover the concentrations of copper, zinc, iron and sodium were reduced in the excised bones. The present study indicates that the lead induced bone toxicity and its deteriorated development is the consequence of a primary oxidative stress. Our results may be helpful in understanding the modulation of biochemical parameters under lead toxicity

Distributed Stochastic Power Control in Ad-hoc Networks: A Nonconvex Case

Utility-based power allocation in wireless ad-hoc networks is inherently nonconvex because of the global coupling induced by the co-channel interference. To tackle this challenge, we first show that the globally optimal point lies on the boundary of the feasible region, which is utilized as a basis to transform the utility maximization problem into an equivalent max-min problem with more structure. By using extended duality theory, penalty multipliers are introduced for penalizing the constraint violations, and the minimum weighted utility maximization problem is then decomposed into subproblems for individual users to devise a distributed stochastic power control algorithm, where each user stochastically adjusts its target utility to improve the total utility by simulated annealing. The proposed distributed power control algorithm can guarantee global optimality at the cost of slow convergence due to simulated annealing involved in the global optimization. The geometric cooling scheme and suitable penalty parameters are used to improve the convergence rate. Next, by integrating the stochastic power control approach with the back-pressure algorithm, we develop a joint scheduling and power allocation policy to stabilize the queueing systems. Finally, we generalize the above distributed power control algorithms to multicast communications, and show their global optimality for multicast traffic.Comment: Contains 12 pages, 10 figures, and 2 tables; work submitted to IEEE Transactions on Mobile Computin

Unique Signatures of Natural Background Radiation on Human Y Chromosomes from Kerala, India

The most frequently observed major consequences of ionizing radiation are chromosomal lesions and cancers, although the entire genome may be affected. Owing to its haploid status and absence of recombination, the human Y chromosome is an ideal candidate to be assessed for possible genetic alterations induced by ionizing radiation. We studied the human Y chromosome in 390 males from the South Indian state of Kerala, where the level of natural background radiation (NBR) is ten-fold higher than the worldwide average, and that from 790 unexposed males as control.We observed random microdeletions in the Azoospermia factor (AZF) a, b and c regions in >90%, and tandem duplication and copy number polymorphism (CNP) of 11 different Y-linked genes in about 80% of males exposed to NBR. The autosomal homologues of Y-linked CDY genes largely remained unaffected. Multiple polymorphic copies of the Y-linked genes showing single Y-specific signals suggested their tandem duplication. Some exposed males showed unilocus duplication of DAZ genes resulting in six copies. Notably, in the AZFa region, approximately 25% of exposed males showed deletion of the DBY gene, whereas flanking genes USP9Y and UTY remained unaffected. All these alterations were detected in blood samples but not in the germline (sperm) samples.Exposure to high levels of NBR correlated with several interstitial polymorphisms of the human Y chromosome. CNPs and enhanced transcription of the SRY gene after duplication are envisaged to compensate for the loss of Y chromosome in some cells. The aforesaid changes, confined to peripheral blood lymphocytes, suggest a possible innate mechanism protecting the germline DNA from the NBR. Genome analysis of a larger population focusing on greater numbers of genes may provide new insights into the mechanisms and risks of the resultant genetic damages. The present work demonstrates unique signatures of NBR on human Y chromosomes from Kerala, India

p53 modeling as a route to mesothelioma patients stratification and novel therapeutic identification

Background Malignant pleural mesothelioma (MPM) is an orphan disease that is difficult to treat using traditional chemotherapy, an approach which has been effective in other types of cancer. Most chemotherapeutics cause DNA damage leading to cell death. Recent discoveries have highlighted a potential role for the p53 tumor suppressor in this disease. Given the pivotal role of p53 in the DNA damage response, here we investigated the predictive power of the p53 interactome model for MPM patients’ stratification. Methods We used bioinformatics approaches including omics type analysis of data from MPM cells and from MPM patients in order to predict which pathways are crucial for patients’ survival. Analysis of the PKT206 model of the p53 network was validated by microarrays from the Mero-14 MPM cell line and RNA-seq data from 71 MPM patients, whilst statistical analysis was used to identify the deregulated pathways and predict therapeutic schemes by linking the affected pathway with the patients’ clinical state. Results In silico simulations demonstrated successful predictions ranging from 52 to 85% depending on the drug, algorithm or sample used for validation. Clinical outcomes of individual patients stratified in three groups and simulation comparisons identified 30 genes that correlated with survival. In patients carrying wild-type p53 either treated or not treated with chemotherapy, FEN1 and MMP2 exhibited the highest inverse correlation, whereas in untreated patients bearing mutated p53, SIAH1 negatively correlated with survival. Numerous repositioned and experimental drugs targeting FEN1 and MMP2 were identified and selected drugs tested. Epinephrine and myricetin, which target FEN1, have shown cytotoxic effect on Mero-14 cells whereas marimastat and batimastat, which target MMP2 demonstrated a modest but significant inhibitory effect on MPM cell migration. Finally, 8 genes displayed correlation with disease stage, which may have diagnostic implications. Conclusions Clinical decisions related to MPM personalized therapy based on individual patients’ genetic profile and previous chemotherapeutic treatment could be reached using computational tools and the predictions reported in this study upon further testing in animal models

Irradiation-induced telomerase activity and gastric cancer risk: a case-control analysis in a Chinese Han population

<p>Abstract</p> <p>Background</p> <p>Telomerase expression is one of the characteristics of gastric cancer (GC) cells and telomerase activity is frequently up-regulated by a variety of mechanisms during GC development. Therefore, we hypothesized that elevated levels of activated telomerase might enhance GC risk due to increased propagation of cells with DNA damage, such as induced by γ-radiation.</p> <p>Methods</p> <p>To explore this hypothesis, 246 GC cases and 246 matched controls were recruited in our case-control study. TRAP-ELISA was used to assess the levels of telomerase activity at baseline and after γ-radiation and the γ-radiation-induced telomerase activity (defined as after γ-irradiation/baseline) in cultured peripheral blood lymphocytes (PBLs).</p> <p>Results</p> <p>Our data showed that there was no significant difference for the baseline telomerase activity between GC cases and controls (10.17 ± 7.21 <it>vs. </it>11.02 ± 8.03, <it>p </it>= 0.168). However, after γ-radiation treatment, γ-radiation-induced telomerase activity was significantly higher in the cases than in the controls (1.51 ± 0.93 <it>vs</it>. 1.22 ± 0.66, <it>p </it>< 0.001). Using the median value of γ-radiation-induced telomerase activity in the controls as a cutoff point, we observed that high γ-radiation-induced telomerase activity was associated with a significantly increased GC risk (adjusted odds ratio, 2.45; 95% confidence interval, 1.83-3.18). Moreover, a dose response association was noted between γ-radiation-induced telomerase activity and GC risk. Age, but not sex, smoking and drinking status seem to have a modulating effect on the γ-radiation-induced telomerase activities in both cases and controls.</p> <p>Conclusion</p> <p>Overall, our findings for the first time suggest that the increased γ-radiation-induced telomerase activity in PBLs might be associated with elevated GC risk. Further confirmation of this association using a prospective study design is warranted.</p

Phase I/II study of oral etoposide plus GM-CSF as second-line chemotherapy in platinum-pretreated patients with advanced ovarian cancer

The aim of this phase I/II study was to determine the maximum tolerated dose (MTD) and the dose-limiting toxicities of chronic oral etoposide given on days 1–10 followed by rescue with subcutaneous (s.c.) granulocyte-macrophage colony-stimulating factor (GM-CSF) on days 12–19 as second-line chemotherapy in platinum-pretreated patients (pts) with advanced ovarian carcinoma. Cohorts of three to six pts were treated with doses of oral etoposide from 750 mg m−2 cycle−1 escalated to 1250 mg m−2 cycle−1 over 10 days, every 3 weeks. Subcutanous GM-CSF, 400 μg once daily, days 12–19, was added if dose-limiting granulocytopenia was encountered. In total, 18 pts with a median Karnofsky index of 80% (range, 70–100%) and a median time elapsed since the last platinum dose of 10 months (range, 1–24 months), 30% of whom showed visceral metastases, were treated at four dose levels (DLs) of oral etoposide on days 1–10 of each cycle as follows: DL 1, 750 mg m−2 cycle−1, without GM-CSF, three pts; DL 2, 1000 mg m−2 cycle−1, without GM-CSF, three pts; DL 3, 1000 mg m−2 cycle−1, with GM-CSF, six pts; and DL 4, 1250 mg m−2 cycle−1, with GM-CSF, six pts. All pts were assessable for toxicity and 16 pts for response. Dose-limiting toxicity (DLT) was reached at DL 4 by three of six pts, showing World Health Organization (WHO) toxicity grade 4. One patient died from gram-negative sepsis associated with granulocytopenia grade 4. Two more pts developed uncomplicated granulocytopenia grade 4. Thus, we recommend that DL 3 can be used for further phase II evaluation (i.e. oral etoposide 1000 mg m−2 cycle−1, days 1–10, followed by s.c. GM-CSF 400 μg, days 12–19). The clinical complete or partial responses in each patient cohort were: DL 1, one of three pts; DL 2, one of three pts; DL 3, three of five pts; and DL 4, two of five pts. In conclusion, in this phase I/II study, we defined the MTD and the dose recommended for the therapy with oral etoposide given over 10 days followed by s.c. GM-CSF in platinum-pretreated patients with advanced ovarian cancer. Our data demonstrate encouraging activity of this regimen and strongly support its further investigation in a phase II study