COMPARISON BETWEEN PRE-PRANDIAL AND POST-PRANDIAL HEART RATE VARIABILITY (HRV)

Abstract : After food ingestion, peptides are released in GIT, which cause local vasodilatation. Therefore, after meals, redistribution of blood occurs b e c a u s e o f s h i f t i n g o f l a r g e a m o u n t s o f b l o o d i n t o G I T . I n n o r m a l individuals, this is well compensated and does not lead to post-prandial hypotension. The mechanism of post-prandial hypotension is well known. We hypothesized that there may be a decrease in parasympathetic activity (tone) after meals to compensate for the change in blood distribution. We carried out the study to find out the changes in the autonomic tone before and after meals (lunch) in normal individuals, using Heart Rate Variability ( H R V ) . F r o m t h e s e r i e s o f R R i n t e r v a l s m a r k e d , t h e t i m e d o m a i n a n d f r e q u e n c y d o m a i n m e a s u r e s o f H R V w e r e o b t a i n e d u s i n g N e v r o k a r d software (version 6.4). Continuous ECG was recorded in 15 healthy adult subjects (mean age 29.06 ± 6.2; 13 males and 2 females). The ECG was r e c o r d e d i n p r e -p r a n d i a l a n d p o s t -p r a n d i a l s t a t e f o r a p e r i o d o f f i v e minutes each as follows: (1) just before the subjects had lunch, (2) 15 minutes after lunch, (3) 1 hour after lunch, and (4) 2 hours after lunch. T i m e d o m a i n a n d f r e q u e n c y d o m a i n m e a s u r e s o f H R V w e r e c o m p a r e d between pre-prandial state and rest of post-prandial states. The autonomic t o n e p a r a m e t e r s d i d n o t s h o w a s i g n i f i c a n t c h a n g e b e t w e e n t h e p r ep r a n d i a l s t a t e a n d t h e i m m e d i a t e p o s t -p r a n d i a l s t a t e . [ R a n g e , i . e . , t h e difference between the maximum and minimum RR intervals (406 ± 161.14 v s . 4 1 6 . 6 6 ± 1 2 5 ) , s t a n d a r d - Synopsis : Ambarish et al studied the changes in autonomic activity (tone) using heart rate variability (HRV) after feeding. Parasympathetic and sympathetic tone was studied in 15 healthy adult subjects before and after lunch. No significant change was seen in both when the autonomic tone parameters were compared. But the authors propose that HRV can be used to detect autonomic neuropathy in diabetics at a very early stage, by c o m p a r i n g p r e -p r a n d i a l a n d p o s t p r a n d i a l H R V

Evidence of co-infection of chikungunya and densonucleosis viruses in C6/36 cell lines and laboratory infected Aedes aegypti (L.) mosquitoes

<p>Abstract</p> <p>Background</p> <p>Densonucleosis viruses are the etiological agents of insect's disease. We have reported the isolation of densovirus from India and its distribution among the natural populations of <it>Aedes aegypti </it>mosquitoes across the country. Since densonucleosis virus persistently infects mosquito populations, and is demonstrated to negatively affect multiplication of dengue virus in <it>Aedes albopictus</it>, it would be interesting to study if this virus has a role in determining the susceptibility of the vector mosquito <it>Ae. aegypti </it>to chikugunya virus.</p> <p>Methods</p> <p>Mosquito cell lines and adult <it>Ae. aegypti </it>mosquitoes infected with densovirus were superinfected with Chikungunya virus and both the viruses were quantitated by determining their genomic copy number by real time amplification. Comparison was made between the log of genomic copy numbers of the viruses in the presence and absence of each other.</p> <p>Results</p> <p>The log of copy number of the viruses did not vary due to co-infection. Even though the RNA copy number of chikungunya virus increased over the period of time, no change was observed in the RNA copy number between the control and the co-infected group on any given day. Similarly, DNA copy number of densovirus also remained unchanged between the control and the co-infected groups.</p> <p>Conclusion</p> <p>Chikungunya virus neither stimulates the replication of densovirus nor is its own replication suppressed due to co-infection. <it>Ae. aegypti </it>mosquitoes with densovirus infection were as susceptible to infection by chikungunya virus as the uninfected mosquitoes.</p

Recent Ancestry of Kyasanur Forest Disease Virus

Clinicians in Asia should consider this disease when diagnosing acute febrile illnesses

Targeting of highly conserved Dengue virus sequences with anti-Dengue virus trans-splicing group I introns

<p>Abstract</p> <p>Background</p> <p>Dengue viruses (DENV) are one of the most important viral diseases in the world with approximately 100 million infections and 200,000 deaths each year. The current lack of an approved tetravalent vaccine and ineffective insecticide control measures warrant a search for alternatives to effectively combat DENV. The <it>trans</it>-splicing variant of the <it>Tetrahymena thermophila </it>group I intron catalytic RNA, or ribozyme, is a powerful tool for post-transcriptional RNA modification. The nature of the ribozyme and the predictability with which it can be directed makes it a powerful tool for modifying RNA in nearly any cell type without the need for genome-altering gene therapy techniques or dependence on native cofactors.</p> <p>Results</p> <p>Several anti-DENV Group I <it>trans</it>-splicing introns (αDENV-GrpIs) were designed and tested for their ability to target DENV-2 NGC genomes <it>in situ</it>. We have successfully targeted two different uracil bases on the positive sense genomic strand within the highly conserved 5'-3' cyclization sequence (CS) region common to all serotypes of DENV with our αDENV-GrpIs. Our ribozymes have demonstrated ability to specifically <it>trans</it>-splice a new RNA sequence downstream of the targeted site <it>in vitro </it>and in transfected insect cells as analyzed by firefly luciferase and RT-PCR assays. The effectiveness of these αDENV-GrpIs to target infecting DENV genomes is also validated in transfected or transformed Aedes mosquito cell lines upon infection with unattenuated DENV-2 NGC.</p> <p>Conclusions</p> <p>Analysis shows that our αDENV-GrpIs have the ability to effectively <it>trans</it>-splice the DENV genome <it>in situ</it>. Notably, these results show that the αDENV-GrpI 9v1, designed to be active against all forms of Dengue virus, effectively targeted the DENV-2 NGC genome in a sequence specific manner. These novel αDENV-GrpI introns provide a striking alternative to other RNA based approaches for the transgenic suppression of DENV in transformed mosquito cells and tissues.</p

Identification of hepatitis B virus genotypes detected in Lahaul & Spiti district of Himachal Pradesh, India

Background & objectives: Infection by hepatitis B virus (HBV) results in acute or chronic hepatitis. Based on sequence differences of eight per cent or more, HBV is divided into 10 genotypes (A to J) and 35 sub-genotypes. Molecular characterization of the circulating HBV genome has helped in understanding the epidemiology and its clinical importance. Spiti valley in Himachal Pradesh, which shares its border with Tibet, is one of the most HBV prevalent areas in India. Since information about the circulating genotype/s of HBV in this area is limited, this study was conducted to identify the circulating HBV genotypes. Methods: The surface and partial reverse transcriptase gene regions were sequenced using 14 hepatitis B surface antigen-positive samples. Results: Out of the 14 hepatitis B surface antigen-positive samples 11 sample gave quality sequence for further analysis. All the 11 samples belonged to subtype ayw2. The phylogenetic and recombination analysis revealed that five out of 11 samples were of genotype CD1 and the rest six were of genotype D3. Interpretation & conclusions: The CD1 recombinant sub-genotype might have immigrated during past or present transcontinental migration between the adjacent countries. Further studies using full-genome sequencing and high sample size will be helpful to understand this epidemiology and to combat the high prevalence of HBV in the area

Early symptom-relief after valvulotomy in mitral stenosis indicates role of lobeline-sensitive intrapulmonary receptors

Respiratory sensations of eight patients with mitral stenosis in response to i.v. lobeline and 6-min walk before percutaneous mitral valvulotomy (PMV) were ‘being short of breath’, pressure in chest, tracheo-bronchial irritation, a desire to cough, persistent dry cough, chest pain and were qualitatively similar amongst 75% (P = 0.005) of the patients. A week after PMV lobeline evoked similar sensations but the threshold dose decreased from 32.4 ± 3.8 to 24.1 ± 3.2 μg/kg (P = 0.001) and pulmonary artery wedge pressure (PAwP), signifying reduction in pulmonary congestion, from 23.1 ± 1.4 to 14.3 ± 3.4 mmHg (P &#60; 0.001). Distance walked in 6 min increased from 217 ± 58 to 319 ± 51.6 m; and mitral valve area from 0.63 ± 0.01 to 1.43 ± 0.26 cm² (P &#60; 0.001). A fall in lobeline-sensation threshold dose indicated reduction in pulmonary congestion and stimulus to juxtapulmonary/J (or pulmonary C fibre) receptors which suggests that they had contributed to the respiratory and viscerosomatic symptoms seen before PMV