Comparison of Low-Dose Non-contrast CT in Detecting Anatomical and Surgically Important Variants of Paranasal Sinuses to Standard Dose Non-contrast CT: Experience from a Tertiary Care Hospital in Sub-Himalayan Region of Northern India.

Computed tomography (CT) is the gold standard for diagnosing sinusitis and anatomical variations and a guide for paranasal sinus (PNS) surgeries. High doses of radiation lead to increased risk of head and neck malignancies, radiation-induced cataracts, hypothyroidism, and hyperthyroidism. The purpose of this study was to assess the effectiveness of low-dose CT as compared to standard-dose CT in the identification of anatomical variants of paranasal sinus and rhinosinusitis. This was a prospective cross-sectional study consisting of 72 patients who were divided equally into cases (underwent low-dose CT for PNS) and controls (underwent CT for PNS using standard dose protocols). Prevalence of anatomical variants and sinusitis were compared. Image quality was assessed using volume CT dose index (CTDIvol), dose length product (DLP), scan length, and noise. Subjective assessment was done by two radiologists, and scores were given. The comparison and analysis of the quantitative and qualitative variables were done. Anatomical variants were comparable among cases and controls, with post-sellar sphenoid being most common and paradoxical middle turbinate being least common surgically important variant. The difference in mean SD of CTDIvol (mGy), DLP (mGy-cm), effective dose (mSv), globe, and air noise between low and standard doses was statistically significant. A moderate agreement (with kappa 0.50) in cases and substantial agreement (with kappa 0.69) in controls was observed between both observers. Low-dose CT PNS and standard-dose CT PNS are comparable in delineating the paranasal sinus anatomy, with a 3.53× reduction of effective radiation dose to patients.

Functional identification of cis-regulatory long noncoding RNAs at controlled false discovery rates.

A key attribute of some long noncoding RNAs (lncRNAs) is their ability to regulate expression of neighbouring genes in cis. However, such 'cis-lncRNAs' are presently defined using ad hoc criteria that, we show, are prone to false-positive predictions. The resulting lack of cis-lncRNA catalogues hinders our understanding of their extent, characteristics and mechanisms. Here, we introduce TransCistor, a framework for defining and identifying cis-lncRNAs based on enrichment of targets amongst proximal genes. TransCistor's simple and conservative statistical models are compatible with functionally defined target gene maps generated by existing and future technologies. Using transcriptome-wide perturbation experiments for 268 human and 134 mouse lncRNAs, we provide the first large-scale survey of cis-lncRNAs. Known cis-lncRNAs are correctly identified, including XIST, LINC00240 and UMLILO, and predictions are consistent across analysis methods, perturbation types and independent experiments. We detect cis-activity in a minority of lncRNAs, primarily involving activators over repressors. Cis-lncRNAs are detected by both RNA interference and antisense oligonucleotide perturbations. Mechanistically, cis-lncRNA transcripts are observed to physically associate with their target genes and are weakly enriched with enhancer elements. In summary, TransCistor establishes a quantitative foundation for cis-lncRNAs, opening a path to elucidating their molecular mechanisms and biological significance.

Detection and identification of ethanal-derived spin-trapped free radicals using headspace thermal desorption gas chromatography-mass spectrometry (TD-GC-MS).

In this study, we demonstrate a novel approach to the detection and identification of the products of spin-trapped free radicals. Hydroxyl free radicals were generated by Fenton-based chemistry in the presence of ethanal and the spin-trapping agent N-tert-butyl-α-phenylnitrone (PBN). The resulting volatile compounds present in the reaction vial headspace were collected using thermal desorption (TD) and analysed by gas chromatography-mass spectrometry (GC-MS). Eleven compounds were detected in the headspace, and their identification was aided by using either a fluorinated or deuterated analogue of PBN as an alternative spin trap and/or deuterated ethanal (CD3CHO) as the secondary source of free radicals. The electron-ionisation (EI) mass spectra clearly demonstrate the "capture" of methyl radicals; two of the compounds detected were identified as containing one methyl group derived from ethanal, and four were shown to contain two methyl groups. This study demonstrates that sampling the reaction headspace using TD-GC-MS is a viable method for analysing products of free radical trapping, and potentially may be applied to a wide range of free radical systems.

Non-compaction of ventricular myocardium with polycystic kidney disease with cardiogenic cerebral embolism.

Non-compaction of ventricular myocardium is a rare cardiomyopathy involving an early arrest of normal compaction of myocardium during fetal ontogenesis. Autosomal dominant polycystic kidney disease (ADPKD) is a hereditary nephropathy characterised by multiple renal cysts replacing the renal parenchyma and extrarenal manifestations. Here, we report a case of 65-year-old man, chronic smoker, presented with sudden onset right brachial monoparesis, exertional dyspnoea, orthopnoea, bipedal swelling and diagnosed as a case of ADPKD with left ventricular non-compaction cardiomyopathy with acute left ventricular failure and cardiogenic cerebral embolism (no evidence of atrial fibrillation); based on characteristic appearance on two-dimensional echocardiography and cardiac magnetic resonance. The patient was managed with guideline-directed pharmacotherapy for heart failure and anticoagulation as a secondary stroke prevention measure. Through this case report, we try to discuss the association between two rare entities and individualisation of treatment options available as a case-based approach, as no standard treatment guidelines are available.

Hypocalcemic cardiomyopathy: a rare presenting manifestation of hypoparathyroidism.

Hypoparathyroidism patients present with features of hypocalcemia like carpopedal spasm, numbness and paresthesias but hypocalcemic cardiomyopathy leading to congestive heart failure (CHF) is a rare presentation. We present here a case of 55-year-old Asian man who was a known case of dilated cardiomyopathy for 6 months, presented with the chief complaints of shortness of breath on exertion and decreased urine output. On general physical examination, features suggestive of CHF were seen. Chvostek and Trousseau's sign was positive. The patient had a history of cataract surgery of both eyes 15 years ago. Further investigations revealed hypocalcemia. Echo showed severe global hypokinesia of left ventricle with left ventricle ejection fraction 15%. This CHF was refractory to conventional treatment, though, with calcium supplementation, the patient improved symptomatically. On follow-up after 3 months, an improvement was seen in the echocardiographic parameters with ejection fraction improving to 25%.

Prevalence of Metabolic Syndrome in Prediabetes.

Aims: To study the prevalence of metabolic syndrome and its components in prediabetes and to compare the anthropometric indices [waist circumference (WC), hip circumference, waist-hip ratio, waist-height ratio] as predictors of metabolic syndrome in prediabetes. Methods: A total of 300 subjects (200 prediabetic cases and 100 matched normoglycemic controls) in the age group of 18-70 years were recruited for the study. Among the cases, there were 38% of males and 62% of females; and there were 33% of males and 67% of females in the control group. Prediabetes was diagnosed using the American Diabetic Association (ADA) criteria, and metabolic syndrome was diagnosed using the International Diabetes Federation criteria. Results: Prevalence of metabolic syndrome was 63% among the cases and 26% among the normoglycemic controls. Among cases, 56.5% of males and 66.9% of females, and among the controls, 36.3% of males and 20.9% of females had metabolic syndrome. The prevalence of metabolic syndrome increased with age and increasing body mass index among both the cases and controls. Central obesity was found to be the most common component of metabolic syndrome among prediabetic males (80.2%) and females (82.2%). The most common cluster of abnormality among the cases and controls was found to be increased WC plus low high-density lipoprotein plus increased triglycerides. Logistic regression analysis was applied to anthropometric indices, and it was found that increased WC had the maximum predictive power for metabolic syndrome among the subjects with prediabetes. Conclusion: Metabolic syndrome was more prevalent in the prediabetic population in comparison to the normoglycemic individuals with increased WC being the most prevalent component. Increased WC had the maximum predictive power for occurrence of metabolic syndrome among prediabetic subjects.

Uncontrolled diabetes as a rare presenting cause of pituitary apoplexy.

Pituitary apoplexy is a rare endocrine emergency. The extent to which hyperglycaemia is a contributory risk factor in the precipitation of pituitary apoplexy is not known. A 38-year-old man with poorly controlled diabetes presented to the emergency department with sudden onset of nausea and headache with drooping of his right eyelid for about 4 days. On physical examination, he had orthostatic hypotension, ptosis of the right eye, lateral and downward positioning of the eye and absent pupillary reflex. Visual field testing of the left eye revealed superolateral quadrantanopia. MRI of the brain showed pituitary macroadenoma with necrosis. Investigations showed hyperglycaemia, decreased T3, T4 with normal Thyroid stimulating hormone (TSH), low serum Leutinizing hormone (LH), Follicle stimulating hormone (FSH), testosterone and low normal serum prolactin levels. About 21% of non-functioning pituitary adenomas present with apoplexy as was seen in our patient. It is likely that his uncontrolled diabetes precipitated this episode of apoplexy as hyperosmolarity and dehydration, caused by hyperglycaemia can lead to changed pituitary microvascular environment increasing the risk of pituitary infarction.

Dandy-Walker variant with precocious puberty: a rare association.

Precocious puberty is characterised by premature appearance of secondary sexual characteristics before the age of 7 years in girls and 9 years in boys. Dandy-Walker malformation comprises a spectrum of intracranial malformations of the posterior fossa. We present a case of a 7-year-old male child who has presented with features of central precocious puberty and on further evaluation has been found to have Dandy-Walker variant and secondary hypothyroidism. The following case report describes this association which is extremely rare and has never been described in literature.

Dulaglutide-induced cerebral venous thrombosis in a patient with type 2 diabetes mellitus.

Though patients with diabetes mellitus are at a high risk of atherothrombotic events, every such event should not be attributed to the disease itself. We present a case of a patient with diabetes with headache and blurring of vision for 3 days. Brain imaging revealed right transverse sinus thrombosis and acute infarct of the right posterior parieto-occipital region, predominantly in the posterior cortical watershed zone. The patient was on subcutaneous dulaglutide for 3 weeks and was having nausea and vomiting. Various causes of cerebral venous thrombosis were ruled out with appropriate laboratory investigations. Finally, cerebral venous thrombosis was attributed to dulaglutide-induced nausea and vomiting which led to severe dehydration.