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In mammalian cells, mature tRNAs are cleaved by stress-activated ribonuclease angiogenin to generate 5'- and 3'-tRNA halves: a novel class of small non-coding RNAs of 30-40 nucleotides in length. The biogenesis and biological functions of tRNA halves are emerging areas of research. This review will discuss the most recent findings on: (i) the mechanism and regulation of their biogenesis, (ii) their mechanism of action (we will specifically discuss their role in the protein synthesis inhibition and the intrinsic pathway of apoptosis), and (iii) their effects on the human physiology and disease conditions., (© 2015 by The American Society for Biochemistry and Molecular Biology, Inc.)

Wrightia tinctoria is a constituent of several ayurvedic preparations against skin disorders including psoriasis and herpes, though not yet has been explored for anticancer potential. Herein, for the first time, we report the significant anticancer properties of a semi-purified fraction, DW-F5, from the dichloromethane extract of W. tinctoria leaves against malignant melanoma. DW-F5 exhibited anti-melanoma activities, preventing metastasis and angiogenesis in NOD-SCID mice, while being non-toxic in vivo. The major pathways in melanoma signaling mediated through BRAF, WNT/β-catenin and Akt-NF-κB converging in MITF-M, the master regulator of melanomagenesis, were inhibited by DW-F5, leading to complete abolition of MITF-M. Purification of DW-F5 led to the isolation of two cytotoxic components, one being tryptanthrin and the other being an unidentified aliphatic fraction. The overall study predicts Wrightia tinctoria as a candidate plant to be further explored for anticancer properties and DW-F5 as a forthcoming drug formulation to be evaluated as a chemotherapeutic agent against malignant melanoma.

Hemihyperplasia is a heterogenous group of disorders characterized by asymmetric limb growth. Confusion regarding their classification and ascertainment into various syndromes still exists. Subtle, asymmetric variation of the unilateral structures of the head, face, trunk or extremities may occur in the general population in the absence of any local lesion or condition.

Hyperglycaemia occurs frequently in critically-ill patients. Not only does it occur among patients with pre-existing diabetes mellitus but elevated blood glucose values during an acute illness can also be seen in previously glucose-tolerant individuals (stress hyperglycaemia). Numerous observational studies have shown an increase in morbidity and mortality in critically ill patients with hyperglycaemia. Interestingly, outcomes in individuals with stress hyperglycaemia are worse than that in critically ill hyperglycaemic patients with pre-existing diabetes. Proper management of hyperglycaemia has been shown to result in improved clinical outcomes. Critically ill patients with hyperglycaemia should primarily be managed with intravenous insulin infusion to allow dynamic adjustment of treatment to suit the rapid changes in blood glucose values in these patients. Currently, there are in existence a fair number of published protocols to administer intensive intravenous insulin therapy that range from the relatively simple to the fairly complex. Different management strategies have been proposed depending upon whether the critically ill hyperglycaemic patient is stationed in the emergency department, the medical intensive care unit (ICU), the surgical ICU or the coronary care unit. Moreover, the ideal target blood glucose value to maintain in this group of patients remains controversial. Keeping these issues in mind, a group of leading experts in the fields of diabetes and critical care extensively reviewed the literature and framed recommendations with special attention to clinical practice in India. The aim was to formulate recommendations which are based on sound evidence and yet are simple and easy to understand and implement across the ICU throughout the country. In the current recommendations, intensive intravenous insulin therapy has been suggested as the preferred mode of managing hyperglycaemia in patients admitted to critical care settings. The current recommendations suggest using a simple and similar protocol for managing hyperglycaemia in critically-ill patients irrespective of their location among the various critical care units in a hospital. Recommendations have also been made for transition from intravenous to subcutaneous administration of insulin when the patient is transferred out of the critical care setting. It is hoped that the current recommendations shall form the basis for the management of hyperglycaemia in critically ill patients across the country.

Stringent monitoring of blood glucose in diabetes plays an important role as the treatment of the disease itself. Blood glucose monitoring (BGM) strategies such as measurement of Hb1Ac, Self-Monitoring of Blood Glucose (SMBG) and Continuous Glucose Monitoring (CGM) plays a vital role in achieving the important goal of preventing long term complications of diabetes. Although the use of BGM is recommended by various international guidelines in T1DM and T2DM, there is no consensus on the utility of BGM in India. So, there is a need to develop a guidance for uniform monitoring mechanism among the care givers taking into account the variations and challenges that are unique to Indian population. A committee was established that comprised of physicians, researchers and other healthcare professionals having expertise in diabetes treatment to oversee the formulation of guidelines on different monitoring and treatment aspects of diabetes. Extensive literature searches were conducted to identify and analyze the evidence available on BGM. An initial draft of BGM guidelines was presented to core members who discussed the subject matter and presented their opinion. This was then taken to wider expert audience to invite their comments that were incorporated in the initial draft. The first compilation was presented at a conference attended by nearly 200 experts. Again, their opinion was sought and the next version was prepared which was sent to core committee members for the final inputs. The Indian consensus guideline on BGM using Hb1Ac, SMBG and CGM as the primary tools was then finalized., (Copyright © 2014 Diabetes India. Published by Elsevier Ltd. All rights reserved.)

Adaptation to changes in extracellular tonicity is essential for cell survival. However, severe or chronic hyperosmotic stress induces apoptosis, which involves cytochrome c (Cyt c) release from mitochondria and subsequent apoptosome formation. Here, we show that angiogenin-induced accumulation of tRNA halves (or tiRNAs) is accompanied by increased survival in hyperosmotically stressed mouse embryonic fibroblasts. Treatment of cells with angiogenin inhibits stress-induced formation of the apoptosome and increases the interaction of small RNAs with released Cyt c in a ribonucleoprotein (Cyt c-RNP) complex. Next-generation sequencing of RNA isolated from the Cyt c-RNP complex reveals that 20 tiRNAs are highly enriched in the Cyt c-RNP complex. Preferred components of this complex are 5' and 3' tiRNAs of specific isodecoders within a family of isoacceptors. We also demonstrate that Cyt c binds tiRNAs in vitro, and the pool of Cyt c-interacting RNAs binds tighter than individual tiRNAs. Finally, we show that angiogenin treatment of primary cortical neurons exposed to hyperosmotic stress also decreases apoptosis. Our findings reveal a connection between angiogenin-generated tiRNAs and cell survival in response to hyperosmotic stress and suggest a novel cellular complex involving Cyt c and tiRNAs that inhibits apoptosome formation and activity., (Copyright © 2014, American Society for Microbiology. All Rights Reserved.)

Background: The hereditary hemoglobin (Hb) disorders are the most commonly encountered single gene disorders in India. Data pertaining to the pattern of hemoglobinopathies and thalassemias is scarce in North East India, and hence it was considered worthwhile to study these disorders using a large series of patients referred to a clinical diagnostic laboratory., Aims: A total of 9000 patients referred for Hb variant analysis were studied to identify hemoglobinopathies and thalassemias in Upper Assam region of North East India., Materials and Methods: This study was performed by high performance liquid chromatography (HPLC) using BIORAD variant Hb typing system., Results: Out of 9000 patients studied, abnormal Hb fractions were seen in 5320 patients. The HbE gene was detected in 4315 patients of which HbE trait was seen in 2294 followed by HbE disease in 1892. There were 114 HbE beta thalassemia patients and 15 double heterozygotes of HbE with HbS or HbD. Beta thalassemia trait was seen in 313 patients and beta thalassemia homozygous in 32. HbS gene was detected in 460 patients comprising of HbS trait in 189, HbS disease in 203, S beta thalassemia in 53 and double heterozygotes of SD and ES in 15. The rest comprised of HbD trait in 6, delta beta thalassemia in 33, hereditary persistence of fetal hemoglobin trait in 5 and J chain hemoglobinopathy in 8 patients. Evidence of alpha thalassemia though suspected, could not be confirmed., Conclusion: A high incidence of hemoglobinopathies and thalassemias and their combinations is unique for this part of the country.

Background: The A1chieve, a multicentric (28 countries), 24-week, non-interventional study evaluated the safety and effectiveness of insulin detemir, biphasic insulin aspart and insulin aspart in people with T2DM (n = 66,726) in routine clinical care across four continents., Materials and Methods: Data was collected at baseline, at 12 weeks and at 24 weeks. This short communication presents the results for patients enrolled from North East, India., Results: A total of 730 patients were enrolled in the study. Four different insulin analogue regimens were used in the study. Patients had started on or were switched to biphasic insulin aspart (n = 518), insulin detemir (n = 88), insulin aspart (n = 74), basal insulin plus insulin aspart (n = 19) and other insulin combinations (n = 30). At baseline glycaemic control was poor for both insulin naïve (mean HbA1c: 9.5%) and insulin users (mean HbA1c: 9.2%) groups. After 24 weeks of treatment, both groups showed improvement in HbA1c (insulin naïve: -1.6%, insulin users: -1.5%). SADRs including major hypoglycaemic events or episodes did not occur in any of the study patients., Conclusion: Starting or switching to insulin analogues was associated with improvement in glycaemic control with a low rate of hypoglycaemia.

Endoplasmic reticulum (ER) stress-induced responses are associated with the loss of insulin-producing β-cells in type 2 diabetes mellitus. β-Cell survival during ER stress is believed to depend on decreased protein synthesis rates that are mediated via phosphorylation of the translation initiation factor eIF2α. It is reported here that chronic ER stress correlated with increased islet protein synthesis and apoptosis in β-cells in vivo. Paradoxically, chronic ER stress in β-cells induced an anabolic transcription program to overcome translational repression by eIF2α phosphorylation. This program included expression of amino acid transporter and aminoacyl-tRNA synthetase genes downstream of the stress-induced ATF4-mediated transcription program. The anabolic response was associated with increased amino acid flux and charging of tRNAs for branched chain and aromatic amino acids (e.g. leucine and tryptophan), the levels of which are early serum indicators of diabetes. We conclude that regulation of amino acid transport in β-cells during ER stress involves responses leading to increased protein synthesis, which can be protective during acute stress but can lead to apoptosis during chronic stress. These studies suggest that the increased expression of amino acid transporters in islets can serve as early diagnostic biomarkers for the development of diabetes.

Certain stress conditions can induce cleavage of tRNAs around the anticodon loop via the use of the ribonuclease angiogenin. The cellular factors that regulate tRNA cleavage are not well known. In this study we used normal and eIF2α phosphorylation-deficient mouse embryonic fibroblasts and applied a microarray-based methodology to identify and compare tRNA cleavage patterns in response to hypertonic stress, oxidative stress (arsenite), and treatment with recombinant angiogenin. In all three scenarios mouse embryonic fibroblasts deficient in eIF2α phosphorylation showed a higher accumulation of tRNA fragments including those derived from initiator-tRNA(Met). We have shown that tRNA cleavage is regulated by the availability of angiogenin, its substrate (tRNA), the levels of the angiogenin inhibitor RNH1, and the rates of protein synthesis. These conclusions are supported by the following findings: (i) exogenous treatment with angiogenin or knockdown of RNH1 increased tRNA cleavage; (ii) tRNA fragment accumulation was higher during oxidative stress than hypertonic stress, in agreement with a dramatic decrease of RNH1 levels during oxidative stress; and (iii) a positive correlation was observed between angiogenin-mediated tRNA cleavage and global protein synthesis rates. Identification of the stress-specific tRNA cleavage mechanisms and patterns will provide insights into the role of tRNA fragments in signaling pathways and stress-related disorders.

A. assamensis is a phytophagous Lepidoptera from Northeast India reared on host trees of Lauraceae family for its characteristic cocoon silk. Source of these cocoons are domesticated farm stocks that crash frequently and/or wild insect populations that provide new cultures. The need to reduce dependence on wild populations for cocoons necessitates assessment of genetic diversity in cultivated and wild populations. Molecular markers based on PCR of Inter-simple sequence repeats (ISSR) and simple sequence repeats (SSR) were used with four populations of wild insects and eleven populations of cultivated insects. Wild populations had high genetic diversity estimates (H(i) = 0.25; H(S) = 0.28; H(E) = 0.42) and at least one population contained private alleles. Both marker systems indicated that genetic variability within populations examined was significantly high. Among cultivated populations, insects of the Upper Assam region (H(i) = 0.19; H(S) = 0.18; H(E) = 0) were genetically distinct (F(ST) = 0.38 with both marker systems) from insects of Lower Assam (H(i) =0.24; H(S) =0.25; H(E) = 0.3). Sequencing of polymorphic amplicons suggested transposition as a mechanism for maintaining genomic diversity. Implications for conservation of native populations in the wild and preserving in-farm diversity are discussed.

Autoimmune polyglandular syndromes (APS) comprise a wide clinical spectrum of autoimmune disorders. APS is divided into Type I, Type II, Type I and Type IV depending upon the pattern of disease combination. Ghronic diarrhoea is one of the many manifestations of APS and many aetiological factors have been suggested for it. Apart from the established aetiological factors, intestinal lymphangiectasia may be responsible for chronic diarrhea in some cases.Intestinal lymphangiectasia has been reported in Type I APS. We report a case of Type III APS with hypocalcaemia and hypothyroidism who had chronic diarrhea of long duration and was finally diagnosed to have intestinal lymphangiectasia.

Diabetic myonecrosis is an underreported complication of long-standing, poorly controlled diabetes mellitus which is usually self-limiting and responds well to conservative management. Patients frequently have microvascular complications, and although short-term prognosis is good, the long-term prognosis is poor. We report four cases of diabetic myonecrosis admitted in a tertiary care hospital.

Dual ectopic thyroid is a rare presentation of thyroid ectopia. Only a few cases have been reported in the world literature. Dual ectopic thyroid in the presence of a normally located thyroid is even rarer. We report a case of dual ectopic thyroid in the lingual and submandibular areas in a seventeen-year-old female with hypoplastic thyroid gland in its normal location. The patient presented with a midline swelling at the base of tongue with dysphagia. Thyroid function test revealed primary hypothyroidism. Ultrasonography of the neck showed hypoplastic thyroid in its normal location. A thyroid scan with Technetium-99 m pertechnate showed two intensely hyperfunctioning foci of ectopic thyroid tissue at a higher level in the midline consistent with dual ectopic thyroid, one at the base of tongue and the other in submental region. No uptake was seen in the normal bed.

The N(1)-methyl-Adenosine (m(1)A58) modification at the conserved nucleotide 58 in the TPsiC loop is present in most eukaryotic tRNAs. In yeast, m(1)A58 modification is essential for viability because it is required for the stability of the initiator-tRNA(Met). However, m(1)A58 modification is not required for the stability of several other tRNAs in yeast. This differential m(1)A58 response for different tRNA species raises the question of whether some tRNAs are hypomodified at A58 in normal cells, and how hypomodification at A58 may affect the stability and function of tRNA. Here, we apply a genomic approach to determine the presence of m(1)A58 hypomodified tRNAs in human cell lines and show how A58 hypomodification affects stability and involvement of tRNAs in translation. Our microarray-based method detects the presence of m(1)A58 hypomodified tRNA species on the basis of their permissiveness in primer extension. Among five human cell lines examined, approximately one-quarter of all tRNA species are hypomodified in varying amounts, and the pattern of the hypomodified tRNAs is quite similar. In all cases, no hypomodified initiator-tRNA(Met) is detected, consistent with the requirement of this modification in stabilizing this tRNA in human cells. siRNA knockdown of either subunit of the m(1)A58-methyltransferase results in a slow-growth phenotype, and a marked increase in the amount of m(1)A58 hypomodified tRNAs. Most m(1)A58 hypomodified tRNAs can associate with polysomes in varying extents. Our results show a distinct pattern for m(1)A58 hypomodification in human tRNAs, and are consistent with the notion that this modification fine tunes tRNA functions in different contexts.

A tendency for magnesium deficiency in patients with diabetes mellitus is well established. Hypomagnesemia is commonly associated with hypokalemia and hypocalcemia. Here, we report a case of a 55 yr old woman with diabetes mellitus, presenting with acute onset quadriparesis, paresthesia and muscle cramps, associated with hypokalemia, hypomagnesemia and hypocalcemia, with total recovery on correction of electrolytes for which no other secondary cause could be ascertained.

12hrs fasting samples of 1485 apparently healthy, Assamese population in the age group of 20-80 yrs., mostly from the urban area of Assam were tested for serum lipid profile that includes total cholesterol, triacylglycerol, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C) and very low density lipoprotein cholesterol (VLDL-C) over a period of three years. The values (median and range in mg/dl) obtained were 170 (93-263); 110 (40-256); 40 (23-73); 103 (40-173) and 22 (8-51) respectively. After grouping these subjects according to the age and sex no significant difference were observed between most of the groups. Median and upper range of total cholesterol, HDL-C and LDL-C were found to be higher in women than in men in all the age groups. But triacylglycerol and VLDL-C concentrations were observed to be higher in the men than women except in age group of 61-70 yrs. It can be suggested that lipid values obtained in this study can be used as the reference value, based on which clinical correlation can be made.

AppDNA is an intermediate in enzyme-catalyzed DNA ligation reactions, and its efficient enzymatic synthesis requires a donor-template duplex of at least 11 base pairs in length. An efficient chemical synthesis of AppDNA with the coupling of an adenosine 5'-phosphorimidazolidate to an immobilized DNA-5'-monophosphate as the key step is described. The adenylation efficiencies of DNA-5'-monophosphate were excellent for oligonucleotides containing less than 11 nucleotides and at least 50% for oligonucleotides containing 15-25 nucleotides.

Over 100 chemical types of RNA modifications have been identified in thousands of sites in all three domains of life. Recent data suggest that modifications function synergistically to mediate biological function, and that cells may coordinately modulate modification levels for regulatory purposes. However, this area of RNA biology remains largely unexplored due to the lack of robust, high-throughput methods to quantify the extent of modification at specific sites. Recently, we developed a facile enzymatic ligation-based method for detection and quantitation of methylated 2'-hydroxyl groups within RNA. Here we exploit the principles of molecular recognition and nucleic acid chemistry to establish the experimental parameters for ligation-based detection and quantitation of pseudouridine (Psi) and N6-methyladenosine (m6A), two abundant modifications in eukaryotic rRNA/tRNA and mRNA, respectively. Detection of pseudouridylation at several sites in the large subunit rRNA derived from yeast demonstrates the feasibility of the approach for analysis of pseudouridylation in biological RNA samples.

Over 100 different chemical types of modifications have been identified in thousands of sites in tRNAs, rRNAs, mRNAs, small nuclear RNAs, and other RNAs. Some modifications are highly conserved, while others are more specialized. They include methylation of bases and the ribose backbone, rotation, and reduction of uridine, base deamination, elaborate addition of ring structures, carbohydrate moieties, and more. We have developed a systematic approach to detect and quantify the extent of known RNA modifications. The method is based on the enzymatic ligation of oligonucleotides using the modified or unmodified RNA as the template. The efficiency of ligation is very sensitive to the presence and the type of modifications. First, two oligo pairs for each type of modification are identified. One pair greatly prefers ligation using the unmodified RNA template over the modified RNA template or vice versa. The other pair has equal reactivity with unmodified and modified RNA. Second, separate ligations with each of the two oligo pairs and the total RNA mixture are performed to detect the presence or absence of modifications. Multiple modification sites can be examined in the same ligation reaction. The feasibility of this method is demonstrated for three 2'O-methyl modification sites in yeast rRNA.

Disorders of thyroid hormone metabolism are commonly encountered in clinical practice. Apart from conditions affecting the thyroid gland, thyroid hormone homeostasis may be altered by medications used in varied clinical settings. Drugs may interfere at different steps in thyroid hormone synthesis or secretion leading to hypothyroidism or thyrotoxicosis or may cause changes in hormone binding leading to difficulties in the interpretation of thyroid function tests. These difficulties have been largely overcome by the development of improved diagnostic tools including radio-active uptake studies, estimation of thyroid auto-antibodies and highly sensitive hormone assays.

Background: Patients who underwent replacement of the ascending aorta with a prosthetic graft for treatment of ascending aortic aneurysm and dissection between January 1992 and December 2000 were studied., Methods and Results: Bentall's operation, using a composite aortic valve and prosthetic graft. was performed in 82 patients (70 males). Indications for the procedure included ascending aortic aneurysm (n=54 including 16 patients with Marfan's syndrome): DeBakey Type I or II aortic dissection (n=26 including 10 patients with Marfan's syndrome) and ascending aortic aneurysm with severe aortic stenosis (bicuspid aortic valve disease) (n=2). Bentall's procedure with the inclusion technique was performed in 72 patients and a Cabrol fistula created in 63 patients. In 10 other patients, coronary button transfer was done without a Cabrol fistula. There were 6 early deaths (7.3%) and 8 patients required re-exploration for excessive bleeding. Eighteen patients showed low cardiac output while the wound of 8 became infected. Postoperative arrhythmia and renal failure was seen in 26 and 6 patients, respectively. Four patients had pericardial effusion. Follow-up ranged from 1 month to 8 years. There were 8 late deaths, the causes of which include congestive heart failure (n=3). cerebral hemorrhage (n=3) and sudden cardiac death (n=2). Two patients reported back with dissection of the descending thoracic aorta and await surgery., Conclusions: Bentall's operation is a safe procedure with an acceptable mortality and morbidity.

Minimally invasive cardiac surgical techniques have been applied recently in the management of variety of cardiac lesions. Between December 1998 and February 1999, fifty patients underwent coronary artery bypass grafting (CABG) under two different techniques. In group A (twenty five patients), CABG was done under cardiopulmonary bypass (CPB) and in group B (twenty three patients), CABG was performed on a 'beating heart' without CPB. Serum concentration of cardiac specific enzymes CPZ-MB and Troponin-T were estimated in all the patients from pre-induction period to 72 hours after the bypass graft. Group A patients exhibited a significant (P<0.05) elevation in the CPK-MB and Troponin-T level as compared to group B. Our results show that the extent of myocardial damage following CABG is significantly less when the procedure is done on a 'beating heart'.

The pathological effects of betel-nut meal consumption in weaned albino rats were studied for a period of 4 weeks. In higher concentrations (60-100%), toxic effects were observed. The rats showed severe diarrhoea and died within 1-3 weeks depending upon the amount of betel-nut meal consumed. In lower concentrations (5-10%), no grossly detectable pathological changes were observed in any one of the experimental rats. With the increase in the concentration of betel-nut meal in the experimental diets, the pathological changes were intensified gradually. The pathological changes observed in the rats fed with experimental diets containing more than 15% betel-nut meal were necrosis of the buccal and intestinal mucosa, splenomegaly, fatty changes in the liver and stunted skeletal growth. Catarrhal enteritis was observed in the rats fed with 15% betel-nut meal and haemorrhagic gastroenteritis was observed when the concentration of the betel-nut meal was raised above 15%.