ICAR: endoscopic skull‐base surgery

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Cobalt-Catalyzed Tandem Deamination, Decarboxylation, and Dehomologation of Primary Amines to Carboxylic Acids in Water

Selective transformation of carboxylic acids through oxidative deamination of primary amines is a catalytically challenging and useful transformation. Herein, we present a simple protocol for the transformation of primary amines to carboxylic acids with the readily accessible, cheap cobalt catalyst in the presence of an oxidant, exhibiting good functional group tolerance. While the deamination reaction of benzylamine derivatives proceeds smoothly to provide the corresponding carboxylic acids, the same with substituted 2-arylethylamines under the reaction conditions resulted in the expulsion of carbon dioxide and leads to the formation of the dehomologation product, i.e., carboxylic acids having one carbon atom less. Experimental studies, including control experiments and kinetic studies, were undertaken to shed light on the mechanism

Endocrine Labomas

Laboratory endocrinology forms an integral part of 21 st century endocrinology. Perhaps, no other specialty of medicine is as closely associated with laboratory as endocrinology. This review intends to highlight the challenges faced by an endocrinologist before interpreting a hormone assay report. This review by no means is holistic but intends to highlight some of the pitfalls of laboratory endocrinology and arouse further interest in this important but neglected section of endocrinology. Lack of standardization, as well as rigorous implementation is some of the major challenges facing endocrine assays in our country. It is essential to be aware not only of the details of the method of analysis of a hormone, the pre-analytical requisites, but also disease-specific analytical issues to prevent unnecessary concern both for the patient, as well as the treating physician, as well as needless investigations. Problems with interpretation of serum prolactin, thyroglobulin, steroid hormone assays, rennin assay and vitamin-D assay have been highlighted

Insight into the Amine-Assisted Metal-free Chemoselctive Reductive Amination of Carbonyl Compounds Under Mild Conditions

Tertiary amines are ubiquitous and play an essential role in organocatalysis, pharmaceuticals, and fine chemicals. Amongst various synthetic procedures known for their synthesis, the reductive amination of carbonyl compounds has been found to be a proficient method. Over the past few decades, different synthetic strategies for reductive amination have been developed. Most of them suffer from the use of transition metals and/or harsh reaction conditions. Herein, we present an efficient, operationally simple protocol for the chemoselective reductive amination of carbonyl compounds to furnish the tertiary amines. The strategy encompasses broad substrate scope under the metal-free condition at room temperature and does not require any solvent. A detailed mechanistic investigation was executed with the aid of control experiments and computational study to shed light on the reaction pathway

Leptin and cancer: Pathogenesis and modulation

Leptin, a product of Ob gene from adipocytes regulates appetite, energy expenditure and body mass composition by decreasing orexigenic and increasing anorexigenic neuropeptide release from hypothalamus. Research over the past few years have suggested leptin/leptin receptor dysregulation to have a role in the development of a large variety of malignancies like breast ca, thyroid ca, endometrial ca and gastrointestinal malignancies, predominantly through JAK/STAT pathway which modulates PI3K/AKT3 signaling, ERK1/2 signaling, expression of antiapoptotic proteins (like XIAP), systemic inflammation (TNF-α, IL6), angiogenic factors (VEGF) and hypoxia inducible factor-1a (HIF-1a) expression. In this review, the current understanding of leptin′s role in carcinogenesis has been elaborated. Also a few agents modulating leptin signaling to inhibit cancer cell growth has been described

Occurrence of osteoporosis & factors determining bone mineral loss in young adults with Graves′ disease

Background & objectives: There is a paucity of data with conflicting reports regarding the extent and pattern of bone mineral (BM) loss in Graves′ disease (GD), especially in young adults. Also, interpretation of BM data in Indians is limited by use of T-score cut-offs derived from Caucasians. This study was aimed to evaluate the occurrence of osteoporosis in active treatment naive patients with GD and determine the factors predicting BM loss, using standard T-scores from Caucasians and compare with the cut-offs proposed by the Indian Council of Medical Research (ICMR) for diagnosing osteoporosis in Indians. Methods: Patients with GD, >20 yr age without any history of use of anti-thyroid drugs, and normal controls without fracture history, drugs use or co-morbidities underwent BM density (BMD) assessment at lumbar spine, hip and forearm, thyroid function and calcium profile assessment. Women with menopause or premature ovarian insufficiency and men with androgen deficiency were excluded. Results: p0 atients with GD (n=31) had significantly lower BMD at spine (1.01±0.10 vs. 1.13±0.16 g/cm 2 ), hip (0.88±0.10 vs. 1.04±0.19 g/cm 2 ) and forearm (0.46±0.04 vs. 0.59±0.09 g/cm 2 ) compared with controls (n=30) (P<0.001). Nine (29%) and six (19.3%) patients with GD had osteoporosis as per T-score and ICMR criteria, respectively. None of GD patients had osteoporosis at hip or spine as per ICMR criteria. Serum T 3 had strongest inverse correlation with BMD at spine, hip and femur. Step-wise linear regression analysis after adjusting for age, BMI and vitamin D showed T 3 to be the best predictor of reduced BMD at spine, hip and forearm, followed by phosphate at forearm and 48 h I 131 uptake for spine BMD in GD. Interpretation & conclusions: Osteoporosis at hip or spine is not a major problem in GD and more commonly involves forearm. Diagnostic criterion developed from Caucasians tends to overdiagnose osteoporosis in Indians. T 3 elevation and phosphate are important predictors of BMD. Baseline I 131 uptake may have some role in predicting BMD

Idiopathic hypoparathyroidism and systemic sclerosis: An association likely missed

Hypoparathyroidism in systemic sclerosis is extremely rare with only a single case reported till date. Idiopathic hypoparathyroidism with systemic sclerosis was diagnosed in a 59-year-old gentleman who had presented with recurrent seizures, instability of gait, skin thickening and tightening over both legs and forearms, and arthritis. Examination was significant for positive Trousseau sign and cerebellar ataxia. Evaluation revealed bilateral symmetrical cerebellar and basal ganglia calcification, sensorineural deafness, low serum calcium, elevated serum phosphorus, normal magnesium, normal vitamin D, low plasma parathyroid hormone, high titer of thyroid peroxidase antibody, positive centromere pattern antinuclear antibody, strongly positive anti-topoisomerase-1 (Scl-70) antibody, nonvisualization of parathyroids on neck ultrasonography and skin biopsy suggestive of hyperkeratosis, increased collagen in dermis, and perivascular lymphomononuclear cell infiltration compatible with scleroderma. Last evaluated 10 months after the diagnosis, his ataxia had improved, he remained seizure-free, Trousseau sign was negative, and he had low-normal calcium calcium with calcium carbonate and calcitriol supplementation and switch from phenytoin to valproate. Further studies are warranted to study the use of serum calcium as a screening test for hypoparathyroidism in patients with systemic sclerosis

Adrenal myelolipoma with keratoconus: A novel clinical association

Adrenal myelolipoma is a benign metaplastic collection of reticuloendothelial cells and adipose tissue, believed to be secondary to chronic stimulation of the adrenals. Keratoconus is the most common corneal ectasia of unknown pathogenesis. Altered expression of proteinases, proteinases inhibitors, and cytokines are believed to have a role. We report for the first time, the occurrence of adrenal myelolipoma in a 52-year-old man with bilateral keratoconus with right corneal scarring for 13 years, who had presented with abdominal pain and heaviness for 4 weeks. Computerized tomography abdomen revealed 7.4 × 7.0 × 6.6 cm hypo-dense variegated left adrenal mass [-71 to -51 Hounsfield Unit (HU)] with smooth borders and poor contrast uptake, suggestive of adrenal myelolipoma, which was biochemically non-functional in view of normal overnight dexamethasone suppressed cortisol (1.4 mcg/dl), 24 h urinary fractionated metanephrines [metanephrines 57 mcg/day (53-341); normetanephrines 95 mcg/day (88-444)], androgen levels [dehydroepiandrostenedione-sulphate 112 mcg/dl (21-123); testosterone 542 ng/dl (275-1200)] with normal visualization of the contralateral adrenal. The cause of this association could not be determined. However, it may be hypothesized that altered adrenal steroid metabolism may have some role in the development of myelolipoma in our patient with keratoconus; in view of increased occurrence of myelolipoma in patients with congenital adrenal hyperplasia (CAH), isolated report of keratoconus in twins with CAH and mice model of keratoconus demonstrating the role of androgens in the development of keratoconus