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Biomedical subjects

S K Shukla

Publications and source records attributed to S K Shukla.

At least 19 recordsLinked to original sources
PubMed2001

Isolation and characterization of a black-pigmented Corynebacterium sp. from a woman with spontaneous abortion.

An unusual black-pigmented coryneform bacterium was isolated from the urogenital tract of a woman who experienced a spontaneous abortion during month 6 of pregnancy. Biochemical and chemotaxonomic analyses demonstrated that the unknown bacterium belonged to the genus Corynebacterium. Phylogenetic analysis based on 16S rRNA sequences (GenBank accession no. AF220220) revealed that the organism was a member of a distinct subline which includes uncultured Corynebacterium MTcory 1P (GenBank accession no. AF115934), derived from prostatic fluid, and Corynebacterium CDC B8037 (GenBank accession no. AF033314), an uncharacterized black-pigmented coryneform bacterium. On the basis of chemotaxonomic and phylogenetic evidence, this organism probably represents a new species and is most closely related to the uncharacterized Centers for Disease Control and Prevention group 4 coryneforms. Our strain is designated CN-1 (ATCC 700975).

Abortion, Spontaneous↗
PubMed2000

The hydropericardium syndrome and inclusion body hepatitis in domestic fowl.

Hydropericardium syndrome, an emerging disease of poultry, has recently been detected in some countries of Asia and America, particularly in broiler birds aged 3-6 weeks. The disease is characterized by its sudden occurrence with high mortality of up to 80% in broilers and low mortality of under 10% in layers, associated with hydropericardium. Its course is of 7-15 days under natural conditions. The causative agent is probably fowl adenovirus serotype 4, belonging to group I aviadenovirus genus of the family adenoviridae, which can be cultivated in primary cell cultures of chicken kidney and embryo liver cells. The transmission of disease occurs laterally by the oral-faecal route. The livers of affected birds show necrotic foci, and basophilic intranuclear inclusion bodies fill the entire enlarged nucleus of some of the hepatocytes. The disease can be diagnosed from its gross lesions, histopathological changes in the liver and by serological tests, such as agar gel diffusion, counter immunoelectrophoresis, indirect haemagglutination and ELISA. It has been brought under control by inactivated liver organ vaccines (0.25 ml/bird) or inactivated cell culture vaccines (10(3.5) LD50/bird) given by the subcutaneous route at 10-15 days of age. The vaccine is effective in the face of an outbreak and significantly reduces the mortality.

Adenoviridae Infections↗
PubMed2000

Desulfovibrio desulfuricans bacteremia in a dog.

Desulfovibrio desulfuricans was isolated from the blood of a dog presenting with fever, anorexia, and rear limb stiffness. The isolate was identified by 16S rRNA gene amplification and sequencing.

Animals↗
PubMed1999

Decreased sensitivity of the ultrarapid urease test for diagnosing Helicobacter pylori in patients with chronic renal failure.

Fifty patients with chronic renal failure and 50 asymptomatic healthy volunteers were studied to determine the prevalence of Helicobacter pylori in the two groups and to compare the results of ultrarapid urease test (URUT) and gastric histology for detecting H. pylori infection. Four gastric antral biopsy specimens were taken. Two specimens were used for the URUT and two were processed routinely. Sections were stained with H&E and Loeffler's methylene blue. Histological examination showed presence of H. pylori in 56% of patients with chronic renal failure (CRF) and in 78% of the controls. The difference was statistically significant (p < 0.05). The URUT was positive in only 16% of patients with CRF compared to 74% in the controls (p < 0.0001). The sensitivity and overall diagnostic accuracy of the URUT to diagnose H. pylori infection were 94.8 and 96%, respectively, in controls but were only 29 and 60%, respectively, in patients with CRF. It is concluded that the prevalence of H. pylori is significantly less in patients with CRF and that the URUT is less sensitive than gastric histology for diagnosing H. pylori infection in these patients.

Adolescent↗
PubMed1998

[Kinetics of receptor-mediated radiotoxicity of 16alpha-[125I]-iodostradiol-3,17beta].

AIM: The radiocytotoxic effects in estrogen receptor (ER) containing MCF-7 cells of a mamma carcinoma were investigated following incubation with [125I]E ranging from 1 h to 24 h. METHODS: The receptor status of the cells was confirmed by immunohistochemical staining. The accumulation of [125I]E in MCF-7 cells was tested in the presence and absence of radioinert E and [127I]E and in ER-negative cells in comparison to ER-positive cells. The subcellular distribution was investigated in 0.25 M Saccharose by ultra centrifugation. The radiocytotoxicity was assessed in ER-positive and negative cells by a standard colony forming assay after incubating with [125I]E (1.85 kBq/ml-55.5 kBq/ml) for 1, 2, 4, 8, 12, and 24 h. RESULTS: A significant cytotoxicity was observed only when ER-rich MCF-7-cells were incubated with [125I]E alone. The maximal cytotoxic effect was a reduction of survival fraction to 20-25%. This was achieved at radioactivity concentrations > 37 kBq/ml. Maximal effect was seen after 8 h incubation, extension of incubation time did not further increase toxicity. CONCLUSION: The results suggest that the radioactivity was bound to ER. Through their nuclear localization radioestrogens tagged with radionuclides emitting very low energy electrons (Auger electrons) bear potential for therapy by ER-mediated deposition of lethal doses of ionizing radiation to single cells without affecting neighbouring cells. But, instead of 125I the shorter-living 123I shall be used for labelling because the deciding radiation effectes occur within the first 8 h.

Biological Transport↗
PubMed1997

Hydropericardium syndrome (HPS) in India: a preliminary study on the causative agent and control of the disease by inactivated autogenous vaccine.

Hydropericardium syndrome (HPS) in broiler birds of 3 to 6 weeks of age was recorded for the first time in the Haldwani area of Nainital district (UP) in India in November, 1994. The overall mortality in 6 poultry farms was 61.62 per cent. The disease was experimentally transmitted by bacteria free infected liver homogenate extract passed through membrane filters of 0.22 and 0.1 mu APD. The aetiological agent was inactivated by heat treatment at 56 degrees C for one hour and 80 degrees C for 10 min. A precipitin band was demonstrated in agar gel immunodiffusion and counter immunoelectrophoresis using infected liver homogenate extract as antigen and homologous antisera raised in the laboratory. The disease was effectively controlled by formalinised and heat inactivated autogenous vaccine prepared from the infected livers of birds which died of natural infection.

Animals↗
PubMed1997

[Influence on extratumoral organ activities of tumor-affinity samarium-153 preparations].

AIM: Possibilities to exercise an influence on the biodistribution of a tumor-affine 153Sm-preparation, samarium-153-nitrilotriacetate (NTA), were tested. METHODS: Animals experiments on tumor-bearing mice after additional application of EDTMP (ethylenediamine tetramethylene phosphonate) for the reduction of extratumorale liver-radioactivity and yttrium chloride for the reduction of unwanted underground radioactivity in bone were carried out. Furthermore, the combination of both measurements was tested. RESULTS: The biodistribution of 153Sm-NTA showed a rather low tumor-radioactivity of app. 0.72%/g. The additional EDTMP-application caused a dose-dependent decrease of the underground-radioactivity in liver especially if given 2 h in advance or simultaneously. The additional application of the stable yttrium salt reduced the bone radioactivity on simultaneous increase of liver- and spleen-radioactivity and practically unchanged tumor-radioactivity. The combined use of EDTMP together with the bone-affine metal salt led to a reduction of liver radioactivity on simultaneous reduction of bone radioactivity. CONCLUSIONS: The background radioactivity can be reduced on unchanged tumor-radioactivity by combined Na-EDTMP/YCl3-application. The present results do not allow a therapeutic exploitation because of the low tumor accumulation.

Animals↗
PubMed1995

Blood biochemical profiles in induced aflatoxicosis of cockerels.

1. Experimental intoxication induced in cockerels with varying doses of aflatoxin fed at the rate of 2.5 micrograms, 5.0 micrograms, and 10.0 micrograms per g of food resulted in appreciable changes in blood biochemical profiles. 2. At all doses the aflatoxin caused decreases in serum total proteins, albumin: globulin ratio, serum total cholesterol, serum calcium and phosphorus and increase in serum globulins, alanine amino transferase (ALT) and aspartate amino transferase (AST) concentrations. 3. No changes in serum bilirubin were observed. 4. Possible mechanisms for such blood biochemical changes are discussed and related to liver cellular damage caused by the aflatoxin toxicity.

Animals↗
PubMed1995

[Biokinetics of tumor-affinity yttrium preparations--2].

After demonstrating that the application form 87Y-NTA-EDTMP-Ca is superior to the so far used citrate form of yttrium especially regarding the tumour/liver and tumour/bone ratios, the relationships between the concentrations of the components in the 87Y-NTA-EDTMP-Ca mixture and the 87Y biokinetics were investigated in tumour-bearing mice. The increase of the EDTMP and Ca2+ concentrations by several orders of magnitude caused no significant changes of tumour radioactivity but a clear radioactivity decrease in the liver, spleen and bone, respectively. The increase of the NTA concentration led also to a radioactivity decrease in all organs and tissues investigated. A significant radioactivity reduction in the tumour could be observed only after administration of rather high NTA amounts. Considerations of the tumour/background ratios depending on different compositions of the injection mixture showed the possibility of optimizing radionuclide biodistribution.

Animals↗
PubMed1995

[Biokinetics of tumor-affinity yttrium preparations--Part 1].

Differences of yttrium biokinetics after application to male tumor-bearing mice of 87Y-citrate were studied in comparison to a 87Y-NTA-EDTMP-Ca mixture after variation of both the manner of application (intraperitoneal vs. intratumoral) and the tumor type (mamma carcinoma vs. melanoma). The application of 87Y as NTA-EDTMP-Ca preparation led--in comparison to the citrate form applied so far--to a similar radionuclide tumor accumulation and distinctly lower extratumoral radioactivities in liver, spleen and skeleton with clearly more favorable tumor/background ratios. Melanomas showed a significantly higher radioactivity accumulation (factor 2-3) after injection of 87Y-NTA-EDTMP-Ca than mamma carcinomas. Intratumoral application led to high initial radioactivities in the tumors. Radioactivity concentrations which are comparable with those after intraperitoneal application were achieved within 4 h after intratumoral application. The application of the EDTMP-containing mixture promises in comparison to the traditional citrate form higher radiation doses in the tumor related to the whole-body radiation exposure. The consequences for a possible tumor therapy will be further investigated.

Animals↗
PubMed1994

An activity gel assay for the detection of DNA helicases and nucleases from cell-free extracts.

An activity gel assay was developed for the detection of DNA helicases in crude extracts. The assay was based on the ability of DNA helicases to unwind radioactive fragments from single-stranded M13 circles that were immobilized in an SDS polyacrylamide gel. The displaced radioactive strands were detected by blotting them to a filter and visualizing the resulting bands by autoradiography. Experiments with purified proteins demonstrated that DNA helicases, endonucleases and exonucleases could produce activity bands. A one-dimensional gel assay was sufficiently sensitive to allow detection of DNA helicase I, DNA helicase II, DNA helicase IV, the RecQ helicase as well as 3 unidentified putative DNA helicases in crude extracts of Escherichia coli. Exonuclease and endonuclease activities from crude extracts could be distinguished from DNA helicase activities by their ATP-independence and from each other by their band morphologies.

Base Sequence↗
PubMed1993

Diagnostic significance of T I < T III and TV1 > TV6 signs in ischaemic heart disease.

One hundred seventy patients with ischaemic heart disease (IHD) and 141 healthy controls were evaluated to assess the diagnostic significance of T I < T III and TV1 > TV6 as compared to widening of QRS-T angle. Number of cases with abnormal widening of QRS-T angle was significantly higher (P < .001) in frontal and horizontal planes in the IHD group. T I < T III sign has 61.2% sensitivity, 74.5% specificity and 25.5% false positivity in diagnosis of IHD. Along with abnormal QRS-T angle widening it gave a specificity of 95.5% but a false positivity of 35% and a low sensitivity index (35.3%). TV1 > TV6 sign has sensitivity, specificity and false positivity of 72.9% 84.4% and 15.6% respectively. Combining it with abnormally wide QRS-T angle did not materially improve these indices. Combining T I < T III and TV1 > TV6 signs gives a sensitivity of 49.4%, specificity of 95% and false positivity of 5% in IHD. This is a good diagnostic index and can be assessed at a quick glance without cumbersome estimation of QRS-T angle.

Electrocardiography↗
PubMed1993

[The effect of ethylenediaminetetramethylenephosphonate on the biodistribution of tumor-seeking radionuclides].

It is well known that after application of radioactive complexes for tumour diagnosis or therapy, such as 67Ga-citrate or radiolanthanide complexes (167Tm- or 169Yb-nitrilotriacetate, -citrate, -alpha-hydroxyisobutyrate, 90Y-citrate, etc.) activity is accumulated not only in the tumour but also in other organs, above all liver and bone. This is the main obstacle to their medical use. Recently published results encouraged us to use ethylenediaminetetramethylene phosphonate (EDTMP) for the reduction of extratumoural liver activity. The results show that even small amounts of EDTMP (1-2 mg/kg BW) reduce the activity deposition in the liver by about one order of magnitude. EDTMP provoked elimination of activity from tumour, skeleton and other tissues but not to the same extent as from the liver. Tumor/liver activity ratios > 5 are achievable in this manner.

Animals↗
PubMed1993

[The effect of bone-seeking metal salts on the biodistribution of tumor-seeking heavy metal complexes].

This work attempted to overcome the problem of unwanted bone radioactivity after injection of tumour-affine heavy-metal compounds (prototype 169Yb-citrate) by pre-application of stable yttrium- and calcium-compounds into tumour-bearing mice in doses of 1 mg metal/kg body weight. The pre-application of stable yttrium and calcium resulted in a smaller bone radioactivity. The most favourable results were achieved by injecting the metal salts simultaneously at or within 5 h before the 169Yb-citrate. On the other hand a strong radioactivity increase in the RES (liver and spleen) by a factor of 2 to 4 was observed after yttrium-preapplication.

Animals↗
PubMed1993

[Long term biokinetics of 169Yb following injection as citrate, hydroxyethylethylenediaminetetraacetate and nitrilotriacetate].

169Yb complexes with known biokinetics in tumour-bearing mice up to 48 h p.i. were injected into healthy mice to study the radionuclide biodistribution in various organs and tissues for 672 h after injection, in order to obtain reliable biokinetic data in an animal model, not affected by tumour-growth, as a basis for the calculation of biological half-life and dose distribution. The results demonstrated the existence of at least two components with different biological half-lives in the organs and tissues investigated. The effective half-lives of these components decreased with increasing stability of the complexes administered. The effective half-life of the fast component was a few hours and that of the slow one between about 200 and 800 h.

Animals↗
PubMed1992

[The effect of Ca-diethylenetriamine pentaacetate on the bio-behavior of tumor-affine metal complexes].

The complexon CaDTPA was injected into tumour-bearing mice in concentrations of 0.05, 0.1, 0.3, and 0.6 mole/l (pH:6) 30 min after the 169Yb-injection. 100 microliters of a 0.3 M CaDTPA solution were injected at different time points (simultaneously, 2, 5, 10, 20, 30, 40 and 50 min, 1, 1.25, 1.5, 2.5 and 10 h) after 169Yb-citrate injection. The animals were killed 24 h after radionuclide administration. A strong radioactivity decrease was observable 24 h p.i. not only in blood, liver, spleen, muscle and bone but also in the tumour if CaDTPA was administered within the first 2 h after ytterbium injection. Thereafter no change in radioactivity could be achieved by DTPA. A time phase in which the Yb could be eliminated from the tissues by means of DTPA (time intervals < 2 h) was distinguishable from a time phase in which it was not attainable for DTPA (time intervals > 5 h). This indicates that the incorporation of Yb into the cells is completed after 5 h and that the metals are intracellularly bound, probably to the lysosomes. Improvements of the scintigraphic tumour detection cannot be expected from the use of complexons.

Animals↗