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Biomedical subjects

R A Khan

Publications and source records attributed to R A Khan.

At least 73 records · Page 4Linked to original sources
PubMed1989

Ferritin levels in professional blood donors.

Iron stores were estimated in 333 professional blood donors by serum ferritin assay. Iron deficiency or depleted iron stores assessed by low serum ferritin levels (less than 12ng/ml) were found in 15% donors. In 51% donors the serum ferritin was within the normal range, while 34% donors had high serum ferritin levels (above 200 and upto 3580 ng/ml). Anaemia (Hb less than 13g/d1) was found in 284 (85%) donors, 51 (18%) of these had iron deficiency or low ferritin levels, 99 (35%) had high and 134 (47%) had normal serum ferritin levels. Iron deficiency in blood donors could be associated with repeated blood donations. High serum ferritin levels could be due to reasons like taking of medicinal iron much beyond the recommended dosage by self initiation. Therefore, estimation of serum ferritin has no value in professional blood donors.

Adult↗
PubMed1989

Serum thyroid hormone levels in liver cirrhosis.

Levels of thyroid hormones, serum thyroxine, triiodothyronine (T3), free thyroxine (FT4), free triiodothyronine (FT3) and thyrotropin (TSH) were measured in 55 patients with liver cirrhosis using radioimmunoassay techniques. Results were compared with 78 controls. The mean serum concentration of T3, FT3 and FT4 were significantly decreased in cirrhotics, while no significant change was noted in serum T4 and TSH levels. T3/T4 ratio was also lower than the normal. This indicates an impaired liver conversion of T4 to T3 in peripheral tissues. Serum T3 and FT3 showed an inverse correlation with serum bilirubin and a positive correlation with serum albumin. T3, FT3 and T3/T4 ratios were significantly low in patients who had ascites as compared to those who had no ascites. This study confirms the presence of abnormalities in serum thyroid hormone levels in cirrhosis of liver. Alteration in serum T3 and FT3 levels correlate well with the disease severity and may be useful in assessing the course and prognosis in cirrhotic patients.

Adolescent↗
PubMed1989

Pharmacodynamic studies on Polypodium vulgare (Linn.).

Aqueous extract of the root of P. vulgare (PV) produced CNS depressant effect. It decreased the spontaneous motor activity, prolonged the pentobarbitone induced hypnosis, reduced body temperature and increased the reaction time to pain stimuli. PV also caused prevention against supramaximal electroshock and pentylenetetrazol induced seizures. PV showed a positive inotropic and chronotropic effect on perfused frog heart and caused hypotension and tachycardia in anaesthetised dogs. The effects were blocked by propranolol. PV produced dose dependent inhibition of contractions of rabbit small intestine and the effect was blocked by propranolol. PV appears to possess CNS depressant and beta-adrenoceptor agonistic activities.

Animals↗
PubMed1989

Influence of Lernaeocera branchialis (Crustacea: Copepoda) on growth rate of Atlantic cod, Gadus morhua.

Influence of Lernaeocera branchialis, a hematophagous copepod, on the growth rate of Atlantic cod, Gadus morhua, was investigated in fish of various sizes. Initially, it appeared that growth, over a 16-mo period, was reduced when single or multiple infections were present. We then examined growth rate by comparing food consumption, weight gain, food conversion efficiency, and condition (k) factor over a 2-mo period and subsequently over a 4 wk in control and experimentally infected fish. Total body weight and length of each fish, controls and infected were determined before and after feeding known weights of food. Adults infected with young parasites consumed more food and gained more weight than controls, especially in the first month, but food conversion efficiency and k-factor were greater than those of controls after 2 mo, but food efficiency was still lower than in controls. In 2 groups of young infected fish, all values were consistently lower than those of uninfected fish of comparable size during the 2-mo period. Three additional trials on immature cod confirmed that infected fish consumed less food and exhibited less growth than infected controls. Our results suggest that only adult cod infected with immature parasites compensate for the infections by increasing food consumption, thus resulting in a transitory weight gain. Additionally, parasites that have completed their reproductive activities still produce subtle effects in the form of low food conversion efficiency in their hosts.

Animals↗
PubMed1988

Polymyositis and hepatocellular carcinoma.

We report a patient with recent onset of acute polymyositis who was subsequently found to have a hepatocellular carcinoma, a rare uncommonly associated malignancy.

Carcinoma, Hepatocellular↗
PubMed1988

Nematode infestation of fillets from Atlantic cod, Gadus morhua, off eastern Canada.

The prevalence and intensity of larval nematodes in fillets of Atlantic cod, Gadus morhua, were examined and compared with similar data from a previous survey conducted about 30 yr ago. Anisakis simplex occurred more often in the nape of the fillet, whereas Pseudoterranova decipiens was the predominant species in napeless fillets. The results suggest an increase in both the prevalence and intensity of P. decipiens in fillets of cod, especially those originating from the Gulf of St. Lawrence and coastal Nova Scotia.

Animals↗
PubMed1988

Experimental transmission, development, and effects of a parasitic copepod, Lernaeocera branchialis, on Atlantic cod, Gadus morhua.

Development and effects of adult Lernaeocera branchialis were studied following experimental transmission to Atlantic cod, Gadus morhua. Growth from the detection of pennella stages to mature adults was approximately 9-10 mo (September-June of the following year) at which time eggs were released and the adult parasites degenerated. Cod from all size groups were susceptible but the prevalence of infection was greater in small fish. Peak mortality, about 30%, occurred within 4 mo after infection and was greatest in young fish with multiple infections. Death was associated with emaciation, blood loss, open lesions, and probable occlusion of branchial blood vessels and/or ventral aorta. Infected fish, especially subadults that survived, consumed less food, gained less weight, had a lower conversion factor, and were substantially smaller than uninfected controls through a 32-wk period. Many of these fish displayed hyperactivity. Large cod that survived the infection and harboured 1 parasite were apparently unaffected but died when stressed. A previous infection conferred no protection against reinfection. Multiple infections delayed gonadal maturation and resulted in significantly lower gonadal somatic indices than in controls. Exposure of infected fish to crude oil fractions or to infection with a hemoprotozoan, Trypanosoma murmanensis, culminated in mortality, weight loss, or low organ somatic indices. It is estimated that considerable losses through mortality and weight gain in young fish occur each year in coastal areas from infections by L. branchialis, particularly in one area where it was estimated that 20% of the population was infected.

Animals↗
PubMed1987

Trypanosoma humboldti n. sp. from the Chilean catshark, Schroederichthys chilensis (Guichenot, 1848).

The morphology of Trypanosoma humboldti n. sp. is described from living and stained specimens obtained from the blood of a catshark, Schroederichthys chilensis. This represents the first report of a trypanosome in fish from the eastern Pacific Ocean. It is distinguished by its size and apparent lack of pleomorphism. The presence of a leech, Branchellion ravenellii, attached to the catshark, raises the possibility that it can act as a vector. Additionally, this leech is recorded for the first time from the Pacific Ocean.

Animals↗
PubMed1986

Effect of concurrent infections of Lernaeocera Branchialis (Copepoda) and Trypanosoma murmanensis (Protozoa) on Atlantic cod, Gadus morhua.

A study was initiated to ascertain the prevalence, effect and interaction of the adult stages of the parasitic copepod, Lernaeocera branchialis, on Atlantic cod concurrently infected with a hematozoan, Trypanosoma murmanensis, by comparing condition (K) factor, organ somatic indices, hematological values and lipid concentrations of the liver from infected and uninfected fish of comparable length. Prevalence of the copepod varied from 9 to 21% and was highest in fish examined on the southern coast of Newfoundland. Body condition and blood values were significantly lower in young cod infected with two parasites whereas only K-factor was altered in two size classes parasitized by one copepod. Although lipid concentrations were similar in three length groups of fish without and infected with L. branchialis, the pooled values were significantly greater among the infected group. Mortality occurred only in juvenile cod infected with the copepod and T. murmanensis concurrently. Cod which survived dual infections had lower K-factor and blood values than controls or fish harboring single, parasitic infections. It is concluded that an infection with an adult L. branchialis does not impair the health of fish in this area of the northwestern Atlantic Ocean, but the presence of T. murmanensis concurrently can potentiate its effect.

Animals↗