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R Raina

Publications and source records attributed to R Raina.

34 records · Page 2Linked to original sources
PubMed1993

The ORF encoding a putative ferredoxin-like protein downstream of the vnfH gene in Azotobacter vinelandii is involved in the vanadium-dependent alternative pathway of nitrogen fixation.

An open reading frame (ORF) in the same operon as, but downstream of, vnfH in Azotobacter vinelandii can code for a ferredoxin-like protein. The role this ORF may play in the vnf (vanadium-dependent alternative) pathway of nitrogen fixation was investigated. Site-directed mutagenesis was used to alter one base in each of the codons specifying amino acids 18 and 19 generating a unique Bg/II site. A kanamycin resistance cartridge was cloned into the Bg/II site. This construct was mobilized into A. vinelandii CA12 (delta nifHDK) strain by conjugation and the mutation was introduced into the genome by marker exchange. The resulting mutant was unable to fix nitrogen under conditions in which the vnf pathway of nitrogen fixation operates. This suggests that this ORF is functional and is essential for the vanadium-dependent alternative pathway of nitrogen fixation in A. vinelandii.

Amino Acid Sequence↗
PubMed1993

The Azotobacter vinelandii nifL-like gene: nucleotide sequence analysis and regulation of expression.

The nucleotide sequence of the Azotobacter vinelandii nifL-like gene (Av-nifL) was determined. The 1.9 kb sequence shows an open reading frame (ORF) of 1577 bp which encodes a polypeptide of 519 amino acids, with a calculated molecular weight of 57,793. Av-nifL has about 50% homology with the Klebsiella pneumoniae nifL gene (Kp-nifL) at the nucleotide level and a little more than 52% homology at the amino acid level. The N-terminal regions show more homology than the C-terminal regions. As is the case in K. pneumoniae, Av-nifL is located just upstream of the A. vinelandii nifA gene (Av-nifA) and both genes constitute an operon. The expression of Av-nifL, however, seems to be independent of NtrA and NtrC. Furthermore, Av-nifL expression is not autogenously regulated by NifA, unlike the case in K. pneumoniae. The expression of an Av-nifL::lacZ fusion in A. vinelandii is inhibited by novobiocin and coumermycin A, which are inhibitors of DNA gyrase.

Amino Acid Sequence↗
PubMed1992

The influence of 2,3-butanedione monoxime on dichlorvos-induced enzymatic changes in buffalo calves.

The effects of administration of 2,3-butanedione monoxime (2,3-BM) or atropine alone and in combination were determined on the blood enzymatic activities of dichlorvos-exposed buffalo calves. Dichlorvos given po at 160 mg/kg body weight produced pronounced inhibition of erythrocyte acetylcholinesterase (AChE) and elevation in serum aminotransferases and phosphatases within 30 min. 2,3-BM administered alone or in conjunction with atropine to dichlorvos-exposed calves significantly reactivated erythrocyte AChE activity whereas atropine was ineffective. The effect of 2,3-BM plus atropine on other enzymatic activities was comparatively greater than that of either drug alone. The results indicated that combined treatment with 2,3-BM and atropine was most effective in reversing dichlorvos-induced enzymatic alterations.

Animals↗
PubMed1991

The therapeutic effects of 2,3-butanedione monoxime and atropine in severe dichlorvos intoxication in buffalo calves.

2,3-Butanedione monoxime and atropine alone or in combination were evaluated for their ability to alleviate the toxicity and to reverse the biochemical changes induced by dichlorvos in the blood of buffalo calves. Treatment with 2,3-butanedione monoxime plus atropine 30 min after oral administration of dichlorvos (160 mg/kg) eliminated the apparent toxic signs within 10-15 min, completely prevented lethality, and reversed the dichlorvos-induced alterations in the concentrations of serum carboxylesterase, total plasma proteins, blood glucose and plasma cholinesterase within 2, 4, 12 and 168 h, respectively. Treatment with either 2,3-butanedione monoxime or atropine alone was less effective but the former was the more potent of the two in counteracting the biochemical effects of dichlorvos. These antidotal studies suggest that 2,3-butanedione monoxime in conjunction with atropine would provide effective therapy against severe dichlorvos intoxication in buffalo.

Animals↗
PubMed1990

The influence of repeated oral administration of dichlorvos on circulating esterases in buffalo calves (Bubalus bubalis).

Alterations in circulating esterases induced by dichlorvos and their reversibility were investigated in male buffalo calves. Changes in blood glucose and total plasma proteins were also monitored. Animals received 4 or 8 mg dichlorvos/kg/day po for 28 consecutive d. Dichlorvos caused dose- and time- dependent significant (P less than 0.01) inactivation of blood esterases. Maximal inhibition of plasma cholinesterase (87-94%) and serum carboxylesterase (51-67%) was observed on the 28th day. An increase in blood glucose and total plasma proteins occurred during the dosing period; these parameters returned to control values in surviving animals within 7 d after the final dose. Activities of esterases returned to 45-70% of normal the 14th d after cessation of dichlorvos dosing.

Administration, Oral↗
PubMed1990

Antimalarial activity of some 4-alkylamino 2/3 methoxy-4-aminodiphenyl sulphones.

From a series of thirty six 2,3, N-substituted 4,4'-diaminodiphenyl sulphones studied for their suppressive activity in mice against blood induced erythrocytic stage of Plasmodium berghei infection, six sulphones (1-6) showed 100% suppressive and curative activity at an intraperitoneal dose of 1 mg/kg x 4 days. These sulphones have been studied for their suppressive activity in still lower doses ranging from 1.0-0.25 mg/kg i.p. x 4 days and for their curative activity at 1 mg/kg i.p. x 4 days in comparison to DDS as standard drug. The maximum tolerated dose of these compounds and DDS has also been determined. These sulphones have better therapeutic efficacy for their suppressive and curative action than DDS.

Animals↗
PubMed1990

Disposition kinetics and dosage regimen of sulfadiadine in crossbred calves.

After a single intravenous administration (100 mg/kg) of sulfadiadine to calves, the distribution half-life, elimination half-life and volume of distribution were 0.353 +/- 0.071 h, 11.2 +/- 0.79 h and 0.55 +/- 0.08 l/kg, respectively. Total body clearance and tissue/plasma ratio were calculated to be 34.8 +/- 4.6 ml.kg-1.1-1 and 1.34 +/- 0.38, respectively. A satisfactory intravenous dosage regimen of sulfadiadine in the treatment of infections in calves would be 125 mg/kg, followed by 100 mg/kg at 24 h intervals.

Animals↗
PubMed1989

Kinetics and thermodynamic transitions of N-acetyl-beta-D-glucosaminidase A and B in free and bound forms: role of cellulose ion-exchangers.

The kinetic and thermodynamic properties of N-acetyl-beta-D-glucosaminidase A (Hex A) and N-acetyl-beta-D-glucosaminidase beta (Hex B) from goat testes were investigated in free and bound (after binding them on ion-exchangers such as DEAE- or CM-cellulose respectively) forms. The optimum pH of free Hex A and Hex B was at 4.2 and 5.4, whereas the bound forms showed the optimum pH at 4.0 and 5.2 respectively. While apparent Km of free and bound Hex A (0.8 and 1.0 mM respectively) did not differ, the Km of Hex B increased when bound on CM-cellulose (Km of free Hex B = 0.96 mM versus bound Hex B = 1.6 mM). Though the free Hex A was more thermo-labile than the free Hex B, both isozymes, on insoluble matrices decayed at faster rates on heating. Activation analysis revealed that the energy of activation (Eoa) for transition state of free Hex B (81 Kcal deg-1 mole-1) did not differ from Eoa of bound Hex B. On the other hand, Eoa of free Hex A declined from 77.2 to 71.1 Kcal deg-1 mole-1 when heat transitions were carried out in free and bound state respectively. Thermodynamic analysis suggested a change in entropy of activation (delta S) of free Hex A and Hex B as 200 and 211 eu respectively. While delta S of Hex B did not change after heat transitions, delta S of Hex A was 182.5 eu.

Animals↗
PubMed1989

Studies on 2,3,N,N'-substituted 4,4'-diaminodiphenylsulfones as potential antimalarial agents.

A series of new 4,4'-diaminodiphenylsulfones substituted at 2 and 3 position and also at primary amino group of the phenyl rings have been synthesized and evaluated for their antimalarial activity against Plasmodium berghei infection in mice. Some of these compounds were active and showed complete inhibition of parasitaemia which included 7a1-7a4, 7b3, 7b4 and 16a at 1 mg/kg i.p. for 4 days and 16a, at 0.3 mg/kg for 4 days. Some compounds tested for their synthetase inhibitory action in cell-free system isolated from P. berghei (7b1, 7b2 and 8b2) were found to be more active than diaminodiphenylsulphone. The difference in order of activity between these in vivo and in vitro tests may be due to differences in their pharmacokinetic properties.

Animals↗
PubMed1988

Characterization of the gene for the Fe-protein of the vanadium dependent alternative nitrogenase of Azotobacter vinelandii and construction of a Tn5 mutant.

A sequence homologous to the conventional nifH gene has been cloned from a different region of the Azotobacter vinelandii genome. Tn5 insertions were obtained in this clone and the mutagenized plasmid was used for marker exchange with A. vinelandii strain CA12 (delta nifHDK) to obtain Tn5 mutants. These mutants exhibited a Nif- phenotype in the presence of vanadium, unlike CA12 which was Nif+ on vanadium-containing medium. The gene in the cloned nifH-like region is therefore apparently involved in the vanadium dependent alternative pathway of nitrogen fixation. This gene, nifH2, has been sequenced and encodes a protein of 289 amino acids that is similar to nifH in nucleotide sequence, deduced amino acid sequence, predicted secondary structure and hydrophobicity profile. A second open reading frame downstream of nifH2 codes for a protein of 64 amino acids, similar to the ferredoxin (Fd)-like protein encoded downstream of nifH* in A. chroococum. Sequence analysis suggests that the nifH2 and Fd-like genes are in a single operon.

Amino Acid Sequence↗
PubMedDate not supplied

Effects of repeated topical application of dichlorvos on blood enzymes and its toxicity in buffalo calves (Bubalus bubalis).

Dichlorvos was applied as spray at 1 and 2% concentrations daily for a period of 28 and 21 consecutive days, respectively to buffalo calves. Animals sprayed with 1% dichlorvos displayed mild to moderate clinical signs of toxicosis during the 4th week of exposure. The higher concentration (2%) produced clinical signs of poisoning after 12-16 applications, and was lethal to one of three animals. Daily spraying of dichlorvos at both concentrations inactivated erythrocyte cholinesterase (ChE) (15-21%), plasma ChE (17-20%) and serum carboxylesterase (5-10%) within 3 days. The extent of inhibition of esterases was increased with repeated treatment and maximal inhibition of erythrocyte ChE (80-89%), plasma ChE (81-91%) and serum carboxylesterase (33-54%) with 1 and 2% concentrations was observed on the 28th and 21st day after start of application, respectively. In surviving animals, blood esterases remained inactivated to the extent of 14-65% on the 14th day after the termination of treatment. Dichlorvos at both concentrations significantly (P less than 0.01) elevated the serum levels of aspartate aminotransferase, alanine aminotransferase, acid phosphatase and alkaline phosphatase. The activities of these enzymes in surviving animals recovered to control values within 14 days after the final application of dichlorvos.

Administration, Topical↗
PubMedDate not supplied

Long-term efficacy and compliance of MUSE for erectile dysfunction following radical prostatectomy: SHIM (IIEF-5) analysis.

Baseline and follow-up data of 54 patients from a single surgical series (1998-2001), who used medicated urethral system for erection (MUSE) for the erectile dysfunction (ED) associated with radical prostatectomy (RP), were obtained. Patients were surveyed using the abridged five-item version of the International Index of Erectile Function (IIEF) questionnaire, commonly referred to as the Sexual Health Inventory of Men (SHIM), to determine presence and severity of ED and efficacy of ED treatment modalities. The mean patient age was 63.7+/-5.6 y and the mean follow-up period was 2.3+/-1.2 y. All patients experienced ED for at least 6 months after their surgery before starting MUSE therapy. Overall, 55% of the patients achieved and maintained erections sufficient for sexual intercourse while on MUSE and 48% continued long-term therapy with a mean use of 2.32+/-1.2 y. The mean presurgery SHIM score in these patients was 19.2+/-1.3, which decreased to 5.2+/-0.5 after surgery and increased to 16.3+/-1.3 after MUSE treatment. A total of 28 patients (52%) discontinued treatment after a mean use of 8+/-1.4 months. The reasons for discontinuation were insufficient erections (n = 16, mean SHIM score of 10.5+/-4.4), switch to other ED therapies (n = 4), natural return of erections (n = 4) and urethral pain and burning (n = 4). Excluding the patients (n = 8) who preferred other therapies and return of natural erections, the compliance to MUSE was 63%. There were no significant differences in the IIEF-5 responses between the patients who had a nerve-sparing technique (n=34) and those who did not (n = 20) or among patients who used different doses (250, 500 or 1000 microg) of MUSE. The results of the current trial indicate that MUSE is a successful treatment option in RP patients with established ED. It appears that a post-treatment SHIM score of > or = 16 defines a successful outcome with MUSE therapy.

Aged↗
PubMedDate not supplied

Sexual dysfunction after pelvic surgery.

Pelvic surgeries are among the most common causes of organic sexual dysfunction in men and women. The impact of nerve-sparing surgery on potency has been well documented in radical prostatectomy. However, its impact on potency needs to be evaluated in other pelvic surgeries. Sexual dysfunction is highly prevalent even after multiple technical advances in the field of oncological surgeries. The prevalence varies from 8 to 82%, depending on the type of pelvic surgery. In females, sexual dysfunction has not been evaluated adequately using validated questionnaires. However, in subspecialized circles, treatment for female sexual dysfunction is becoming routine. Currently, physicians have several options for the treatment of erectile dysfunction (ED) in men. Since the introduction of oral PDE-5 inhibitors, oral therapy has become the first-line treatment option for ED, irrespective of etiology. Currently available treatment options for the female sexual dysfunction include estrogens, androgens, phosphodiesterase inhibitors, and dopamine receptor antagonists. Initial reports regarding the role of early rehabilitation are encouraging and may become the part of routine practice in the management of ED after pelvic surgery. In this article, we summarize the sexual dysfunction following pelvic surgeries and their management.

Animals↗
PubMedDate not supplied

Early use of vacuum constriction device following radical prostatectomy facilitates early sexual activity and potentially earlier return of erectile function.

To assess the efficacy of vacuum constriction devices (VCD) following radical prostatectomy (RP) and determine whether early use of VCD facilitates early sexual activity and potentially earlier return of erectile function. This prospective study consisted of 109 patients who underwent nerve-sparing (NS) or non-nerve-sparing (NNS) RP between August 1999 and October 2001 and developed erectile dysfunction following surgery. The patients were randomized to VCD use daily for 9 months (Group 1, N=74) or observation without any erectogenic treatment (Group 2, N=35). Treatment efficacy was analyzed by responses to the Sexual Health Inventory of Men (SHIM) (abridged 5-item International Index of Erectile Function (IIEF-5)), which were stratified by the NS status. Patient outcome regarding compliance, change in penile length, return of natural erection, and ability for vaginal intercourse were also assessed. The mean patient age was 58.2 years, and the minimum follow-up was 9 months. Use of VCD began at an average of 3.9 weeks after RP. In Group 1, 80% (60/74) successfully used their VCD with a constriction ring for vaginal intercourse at a frequency of twice/week with an overall spousal satisfaction rate of 55% (33/60). In all, 19 of these 60 patients (32%) reported return of natural erections at 9 months, with 10/60 (17%) having erections sufficient for vaginal intercourse. The abridged IIEF-5 score significantly increased after VCD use in both the NS and NNS groups. After a mean use of 3 months, 14/74 (18%) discontinued treatment. In Group 2, 37% (13/35) of patients regained spontaneous erections at a minimum follow-up of 9 months after surgery. However, only four of these patients (29%) had erections sufficient for successful vaginal intercourse and rest of patients (71%) sought adjuvant treatment. Of the 60 successful users, 14 (23%) reported a decrease in penile length and circumference at 9 months (range, 4-8 months) compared to 12/14 (85%) among the nonresponders. However, in control group 22/35 reported decrease in penile length and circumference. Early use of VCD following RP facilitates early sexual intercourse, early patient/spousal sexual satisfaction, and potentially an earlier return of natural erections sufficient for vaginal penetration.

Aged↗
PubMedDate not supplied

Isolation and characterization of a locus from Azospirillum brasilense Sp7 that complements the tumorigenic defect of Agrobacterium tumefaciens chvB mutant.

The chromosomal virulence gene chvB of Agrobacterium tumefaciens is required for pathogenesis. A DNA fragment from the chvB locus can hybridize to DNA from Azospirillum brasilense Sp7. This DNA fragment could restore the tumorigenic activity of the chvB mutant strain A. tumefaciens A1011 towards leaf disks of Nicotiana tabacum. An NH2-terminal open reading frame, 480 codons long, was most likely responsible for the restoration of the tumorigenic activity. The A. brasilense sequence showed good homology with the NH2-terminal region of the ndvB gene of Rhizobium meliloti.

Agrobacterium tumefaciens↗