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Biomedical subjects

D J Cole

Publications and source records attributed to D J Cole.

14 recordsLinked to original sources
PubMed1992

Focal cerebral ischemia in rats: effect of hemodilution with alpha-alpha cross-linked hemoglobin on CBF.

Hemodilution has had limited success as a treatment of cerebral ischemia. When using a nonoxygen binding fluid, the therapeutic efficacy of hemodilution-induced increases in CBF are offset by concomitant decreases in oxygen content. The effect of hemodilution, with diaspirin alpha-alpha cross-linked hemoglobin (DCLHb), on CBF during middle cerebral artery occlusion was assessed. Rats were hemodiluted to one of the following hematocrits (Hct): (a) 44/Hct, (b) 37/Hct, (c) 30/Hct, (d) 23/Hct, (e) 16/Hct, or (f) 9/Hct. After 10 min of ischemia, CBF was determined with 14C-iodoantipyrine. Coronal brain sections were evaluated for areas with a CBF of 0-10 and 11-20 ml 100 g-1 min-1. In addition, oxygen delivery was calculated. In the center of the ischemic zone, both areas of low CBF were less in the 30/Hct, 23/Hct, and 16/Hct groups compared with the 44/Hct and 37/Hct groups; and both areas were less in the 9/Hct group compared with the other five groups (p < 0.05). For the hemisphere contralateral to occlusion, there was a direct correlation between hematocrit and oxygen delivery. However, for the hemisphere ipsilateral to occlusion, oxygen delivery increased as hematocrit decreased (44/Hct, 8.6 +/- 0.3 vs. 9/Hct, 13.6 +/- 0.4 [mean +/- SD, ml 100 g-1 min-1]). The results of this study support a hypothesis that hemodilution with DCLHb decreases the extent of focal cerebral ischemia.

Animals↗
PubMed1992

A pilot study of accelerated fractionation in the radiotherapy of invasive carcinoma of the bladder.

24 patients with muscle invasive carcinoma of the bladder were treated in a pilot study of twice daily fractionation at radiation doses of 1.8-2.0 Gy per fraction to total doses of 54-64 Gy to the bladder and 39.6-44 Gy to the whole pelvis. The treatment aim was to give 32 fractions in 22 days. The interfraction interval was a minimum of 6 h. The principle objective was to record acute and late tolerance, but local control and survival data is also presented. Acute radiation morbidity was scored according to the RTOG system. Grade 2 large bowel effects were seen in 52% of patients, Grade 3 effects in 26% and there was one Grade 4 and one Grade 5 effect. The mean duration of effect was 4.5 weeks although the more severe reactions were also more protracted. Grade 2 urinary effects occurred in 30% and Grade 3 in 17% of patients. The mean duration of effect was 7.2 weeks. There were no Grade 4 or 5 acute urinary effects. Late radiation morbidity was scored according to the EORTC/RTOG system and was assessable in 16 cases who survived more than 6 months. There were two cases (12%) of Grade 1 bowel toxicity, two cases of Grade 1 and three of Grade 2 urinary toxicity. There were no cases of late skin effects. Actuarial analysis at 2 years shows a local control probability of 56% and survival probability of 35%.

Acute Disease↗
PubMed1992

Temporary cerebral ischemia. Effects of pentastarch or albumin on reperfusion injury.

Recent investigations have proposed that, after temporary ischemia, pentastarch may reduce microvascular permeability and reperfusion injury. However, this hypothesis has not been tested in the brain. Accordingly, after 180 min of temporary middle cerebral artery occlusion, the effect of pentastarch or albumin on blood-brain barrier permeability and cerebral injury was investigated in isoflurane-anesthetized rats. One of the following was maintained for the final 60 min of occlusion and throughout reperfusion: control-hematocrit was not manipulated; pentastarch-hematocrit was decreased to approximately 30% with pentastarch; or albumin-hematocrit was decreased (approximately 30%) with albumin. Part A (n = 21): 30 min of reperfusion was allowed, and blood-brain barrier permeability was determined with the indicator dye Evans Blue. Part B (n = 14): in different animals, 120 min of reperfusion was allowed, and cerebral injury (2,3,5-triphenyltetrazolium chloride stain) and edema (specific gravity) were assessed. Part C (n = 4): in different animals, the blood-brain barrier was evaluated by electron microscopy. Evans Blue (micrograms per gram brain tissue, mean +/- SD) was greater in the control (20.8 +/- 9.0) and albumin (15.5 +/- 7.3) groups versus the pentastarch (4.7 +/- 2.7) group (P less than 0.05). Brain injury (percent of hemisphere ipsilateral to occlusion) was less and specific gravity greater in the pentastarch (33 +/- 8 and 1.040 +/- 0.003 respectively) versus the albumin group (45 +/- 6 and 1.035 +/- 0.003). This study supports the hypothesis that during temporary cerebral ischemia, pentastarch decreases brain injury and edema.(ABSTRACT TRUNCATED AT 250 WORDS)

Albumins↗
PubMed1979

Pulmonary embolism associated with hemolymphangioma of lower extremity.

We present a case of major pulmonary embolization from a hemolymphangiomatous malformation of the loin and lower extremity. Treatment was with a low-dose infusion of urokinase for a short period directly into the pulmonary artery, and dramatic clinical improvement was noted. Prolonged maintenance therapy was with a low dose of heparin.

Adult↗
PubMed1979

Avermectins, new family of potent anthelmintic agents: isolation and chromatographic properties.

The avermectins, a family of new anthelmintic agents, were isolated from the mycelia of Streptomyces avermitilis. Four closely related major components and four homologous minor components were separated from the complex. Solvent extraction, solvent partition, and adsorption methods were used to isolate and purify the complex; novel partition chromatography systems using Sephadex LH-20 were used to separate the components. A reverse-phase high-pressure liquid chromatography assay for the quantitative determination of all components was used extensively to monitor the purification methods.

Anthelmintics↗
PubMed1978

The variation in the concentration of plasma amino acids and blood urea in pregnant sows.

Two pregnant sows were fed on a basal diet consisting of equal amounts of ground barley and ground wheat with or without addition of L-lysine hydrochloride. Plasma amino acid and blood urea levels varied according to the time after feeding. Almost all the essential amino acids reached a maximum level after one hour and then declined at four hours after feeding. The results suggested that samples taken at between one and four hours after feeding were responsive to changes in dietary composition and could provide a measure to evaluate the amino acid pattern in relation to feeding. Both plasma amino acid and blood urea data suggested that lysine was the first limiting amino acid in the basal diet.

Amino Acids↗
PubMed1978

Amino acid requirements of the breeding sow: the dietary lysine requirement during pregnancy.

1. Four pregnant sows were used to study lysine requirements by means of the interpretation of values for plasma amino acid and blood urea. Diets containing graded levels of dietary lysine were fed at the rate of 1.82 kg/d. 2. Plasma lysine remained at a low level up to 6.4 g dietary lysine/kg (dry matter basis) and then increased sharply with further increases in lysine intake. 3. Blood urea levels decreased when the dietary lysine content was increased to 6.4 g/kg and then increased at higher dietary lysine concentrations. 4. Both criteria of response indicated that the lysine requirement of the pregnant sow given 1.82 kg diet/d during the later stages of pregnancy does not exceed 10.00 g/d.

Amino Acids↗
PubMed1978

Amino acid requirements of the breeding sow. 2. The dietary lysine requirement of the lactating sow.

1. Two experiments, involving six lactating Landacre x (Landrace x Large White) sows were undertaken to study the lysine requirement of the lactating sow and to identify the second limiting amino acid by means of interpretation of plasma amino acid and blood urea levels. 2. A basal diet composed mainly of equal amounts of ground barley and ground wheat supplemented with mineral and vitamin mixtures was used. This diet was supplemented with synthetic amino acids (lysine threonine, tryptophan, methionine and isoleucine). 3. Plasma amino acid and blood urea values showed a close agreement and indicated that lysine intake above 38.4 g/d was in excess of the requirement level. 4. Plasma amino acid values suggested tryptophan to be the second limiting amino acid whereas blood urea values suggested threonine to be the second limiting amino acids.

Amino Acids↗
PubMed1977

Nitrogen retention in the pig.

I. Published results have been used to study the relationships between nitrogen retention (NR), body-weight (W) and N intake in the pig. 2. The general decrease in maximal NR (g/d per kg W0.75) with increasing W (kg) was curvilinear for values of W from 1-5 to 45: NR = 3.324--0.098 W + 0.001 W2; and rectilinear for values of W from 45 to 165: NR = 1.252--0.006 W. Values for protein requirements derived from these equations agreed closely with published estimates. 3. The slopes of the curves for NR (g/d per kg W0.75) v. N intake (g/d) decreased as W (kg) increased from about 2.5 to 190. After extrapolation to a proposed common intercept on the NR axis of--150 mg N/d per kg W0.75, regression analysis of the intercepts of these curves on the N-intake axis v. W gave an estimate of N requirements for maintenance of 246 + 19 mg/d per kg W0.75. 4. The results also indicated that at low N intakes net protein utilization (N retention + total obligatory N losses divided by N intake) was essentially independent of W, whereas the gross efficiency of N utilization (NR divided by N intake) was influenced by both W and N intake.

Animals↗