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  • Author or Editor: Sanjeev Singh x
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Abstract

The physiology of baroreceptors and chemoreceptors present in large blood vessels of the heart is well known in the regulation of cardiorespiratory functions. Since large blood vessels and peripheral blood vessels are of the same mesodermal origin, therefore, involvement of the latter in the regulation of cardiorespiratory system is expected. The role of perivascular nerves in mediating cardiorespiratory alterations produced after intra-arterial injection of a nociceptive agent (bradykinin) was examined in urethane-anesthetized male rats. Respiratory frequency, blood pressure, and heart rate were recorded for 30 min after the retrograde injection of bradykinin/saline into the femoral artery. In addition, paw edema was determined and water content was expressed as percentage of wet weight. Injection of bradykinin produced immediate tachypneic, hypotensive and bradycardiac responses of shorter latency (5–8 s) favoring the neural mechanisms involved in it. Injection of equi-volume of saline did not produce any responses and served as time-matched control. Paw edema was observed in the ipsilateral hind limb. Pretreatment with diclofenac sodium significantly attenuated the bradykinin-induced responses and also blocked the paw edema. Ipsilateral femoral and sciatic nerve sectioning attenuated bradykinin-induced responses significantly, indicating the origin of responses from the local vascular bed. Administration of bradykinin in the segment of an artery produced reflex cardiorespiratory changes by stimulating the perivascular nociceptors involving prostaglandins. This is a novel study exhibiting the role of peripheral blood vessels in the regulation of the cardiorespiratory system.

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Authors: Azad Singh, Megha Bedekar, Rakesh Sharma, Bikash Sarkhel, Sanjeev Singh and Sudhir Jain

In order to detect infectious bursal disease virus (IBDV), bursal tissue was collected from 10 IBD-suspected birds from a 30-day-old, IBDV-vaccinated commercial broiler chicken flock of 2000 birds exhibiting clinical signs suggestive of infectious bursal disease (IBD). The presence of IBDV was confirmed by partial amplification of the VP2 gene by reverse transcription and polymerase chain reaction. Isolates were identified as very virulent strains of IBDV (vvIBDV) by nucleotide sequence analysis. The comparison of the VP2 nucleotide sequences among the isolates revealed the presence of single-nucleotide polymorphisms in the VP2 gene of IBDV in the same flock. The comparative analysis indicated that these viruses were genetically close to the vvIBDVs previously detected in India. Our analysis provided information about the existence of vvIBDV in Central India.

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In this paper we deduce some tight Turán type inequalities for Tricomi confluent hypergeometric functions of the second kind, which in some cases improve the existing results in the literature. We also give alternative proofs for some already established Turán type inequalities. Moreover, by using these Turán type inequalities, we deduce some new inequalities for Tricomi confluent hypergeometric functions of the second kind. The key tool in the proof of the Turán type inequalities is an integral representation for a quotient of Tricomi confluent hypergeometric functions, which arises in the study of the infinite divisibility of the Fisher-Snedecor F distribution.

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