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Biomedical subjects

K Krishan

Publications and source records attributed to K Krishan.

At least 19 recordsLinked to original sources
PubMed1996

Changes in some troponin and insulin-like growth factor messenger ribonucleic acids in regenerating and denervated skeletal muscles.

To investigate the role of innervation and to determine if the process of muscle differentiation is preprogrammed, the expression of insulin-like growth factors (IGF-I and IGF-II), troponin I and troponin T mRNAs was studied in regenerating transplants of rat Extensor digitorum longus muscle in the presence and absence of nerve. The role of innervation was further investigated by denervating some adult fast (Gastrocnemius and Plantaris) and slow (Soleus) skeletal muscles. In normal adult skeletal muscles, IGF-I, IGF-II and developmental fast troponin T mRNA containing exon y, are undetectable or present at very low levels. Induction of all these mRNAs was observed in regenerating muscles in both the presence and absence of nerve as well as following denervation of adult fast and slow skeletal muscles. Their low level expression was maintained in adult denervated skeletal muscles but gradually suppressed in both innervated and noninnervated regenerating extensor digitorum longus muscle transplants after 2 months. Fast troponin T mRNA was synthesized in both innervated and noninnervated EDL transplants although the level of this transcript changed markedly in response to denervation of both adult fast and slow skeletal muscles. The fast troponin T mRNA containing exon 17 was also initially expressed in both regenerating muscles but its level was reduced with time in both transplants and in all adult denervated skeletal muscles. Fast and slow troponin I mRNAs were synthesised during EDL muscle regeneration in both the presence and absence of nerve but the slow troponin I expression was not maintained in noninnervated transplants. The level of fast troponin I mRNA decreased in denervated fast skeletal muscles but markedly increased in denervated Soleus. The level of slow troponin I mRNA was slightly increased in denervated fast skeletal muscles but considerably reduced in denervated Soleus.

Animals↗
PubMed1989

Circannual rhythmicity in the occurrence of idiopathic priapism in north-western India.

A group of 26 patients who were operated upon for idiopathic priapism between 1972 and 1986 were classified according to the date on which they attended hospital. During the same 15-year period 150 patients with penile cancer were treated and they served as controls. The data were analysed for circannual rhythmicity (365.25 days = 360 degrees and 0 degrees = 22 December. This revealed a significant circannual rhythmicity in the occurrence of idiopathic priapism, with the acrophase located on 2 August. There was a significantly higher incidence of idiopathic priapism between April and September.

Adolescent↗
PubMed1989

The loss of circadian rhythmicity of urinary solute excretion in idiopathic stone formers.

Circadian rhythmicity in urinary volume and excretion of creatinine, calcium, oxalate, uric acid and phosphate was studied in 15 idiopathic stone formers and in 17 control subjects who were age-matched, related adult males, living in the same house and engaged in similar occupations to those of the stone patients, but who had no clinically obvious stone disease. Three-hourly urine samples were collected and creatinine, calcium, oxalate, uric acid and inorganic phosphate were estimated. The time series of data were analysed by cosinor rhythmometry. Circadian rhythmicity has been described in urinary volume and urinary excretion of creatinine, calcium, oxalate, uric acid and inorganic phosphate in normal subjects, but it was not detected in the stone formers. The control subjects exhibited a circadian rhythmicity only in urinary volume and creatinine excretion. Thus they occupied a position midway between healthy adults, who exhibit circadian rhythmicity in all of the above parameters, and the stone formers, who appear to have lost it altogether.

Adult↗
PubMed1989

Comparative study of the circadian rhythmicity in the urinary concentration of glycosaminoglycans in patients of calcium oxalate nephrolithiasis and in healthy adults.

Glycosaminoglycans (GAGs) are potent inhibitors of calcium oxalate crystallisation and/or crystal aggregation. Urinary concentration of GAGs has been shown to vary during 24 h; therefore, circadian rhythmicity in urinary concentration of GAGs was investigated in 33 healthy male adults in the age group of 20-40 years and in 27 male patients of a similar age group with calcium nephrolithiasis. Three-hourly urine samples were collected for 24 h beginning from 00.00 h for estimation of urinary concentration of GAGs. The data of each patient was analysed by single cosinor rhythmometry and population mean-cosinor rhythmometry was then applied to each group. Twenty-four-hour urinary excretion of GAGs was significantly less in renal calculus patients (16.867 +/- 5.89 mumol) than in healthy subjects (22.588 +/- 5.32 mumol; p less than 0.001). A statistically validated circadian rhythm in urinary concentration of GAGs was demonstrated in both the groups. However, the amplitude-acrophase test revealed a significant difference between the two groups (F2,57 = 8.305; p less than 0.001); the amplitude was 2.354 mumol/l in patients with nephrolithiasis, whereas the amplitude was 7.028 mumol/l in healthy adults. The mesor test also revealed a significant difference in the 3-hour urinary concentration of GAGs between the two groups (18.536 mumol/l in healthy adults vs. 9.728 mumol/l in patients with nephrolithiasis). Thus in patients with nephrolithiasis, not only is the 24-hour urinary excretion of GAGs significantly low but the 3-hourly urinary concentration of GAGs is also significantly decreased as compared to healthy subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Skeletal muscle metabolism in mice bearing adenocarcinoma. III. Activities of alanine and aspartate aminotransferases.

Activities of alanine and aspartate aminotransferases in six skeletal muscles demonstrate 114-223% and 86-146% increase respectively, over the normal by the 10th week after adenocarcinoma transplantation in mice. The white (anaerobic) muscles reveal greater increment in these two enzymes than the red (aerobic) ones. The significance of elevated aminotransferase activities in energy metabolism of the host muscles is discussed.

Adenocarcinoma↗