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Biomedical subjects

R Martin

Publications and source records attributed to R Martin.

At least 559 records · Page 31Linked to original sources
PubMed1986

Improved protein kinetics and albumin synthesis by branched chain amino acid-enriched total parenteral nutrition in cancer cachexia. A prospective randomized crossover trial.

A prospective randomized crossover trial was conducted to determine the effect of a branched chain amino acid (BCAA)-enriched solution on whole body leucine kinetics and fractional rates of albumin synthesis in patients with intra-abdominal metastatic adenocarcinoma. Ten malnourished cancer patients were provided isonitrogenous amounts of both a conventional total parenteral nutrition (TPN) formula containing 19% BCAA and a BCAA-enriched TPN formula containing 50% of the amino acids as BCAA in a random order. Whole body protein turnover was determined by a 10 hour continuous infusion of leucine 14C. Increased whole body leucine flux (68 +/- 5 mumols/kg BW/hr versus 145 +/- 11; mean +/- SEM; P less than 0.001) and oxidation (13 +/- 2 mumols/kg BW/hr to 46 +/- 5; P less than 0.001) were determined on the BCAA-enriched TPN. Increased whole body protein synthesis (2.2 +/- 0.2 g protein/kg BW/day versus 3.9 +/- 0.3; P less than 0.005) and leucine balance (2.5 +/- 0.4 g leucine/d versus 6.5 +/- 0.6; P less than 0.001) were also observed in patients receiving the BCAA-enriched TPN solution. Leucine release from protein breakdown was not statistically elevated (1.65 +/- 0.18 g protein/kg BW/d versus 2.48 +/- 0.40; P greater than 0.05) but, incorporation of leucine 14C into plasma albumin was significantly elevated (2.37 +/- 0.23 mumols/g/hr to 4.21 +/- 0.33; P less than 0.001) when the patients received BCAA-enriched TPN. Despite the better leucine balance, the improvement in the 24-hour urinary nitrogen balance was not statistically significant (6.6 +/- 3.9 g protein/d versus 11.4 +/- 2.9; control versus BCAA-enriched; P = 0.15). BCAA-enriched formulas improve whole body leucine kinetics, fractional rates of albumin synthesis, and leucine balance, and thus may favorably influence protein metabolism in cancer cachexia.

Abdominal Neoplasms↗
PubMed1986

Terpene hydrocarbons in Pimpinella anisum L.

The essential oil of anise (fruits and shoots) was investigated focusing on the composition of the hydrocarbon fraction. Several sesquiterpenes were identified by GC-MS and the relative composition of the fractions was established by GC analysis. gamma-Himachalene and the diterpene neophytadiene were isolated by TLC and column chromatography at low temperatures. Their structures were determined by MS and NMR including 1H-1H correlated COSY and NOE experiments.

Chromatography, Gas↗
PubMed1986

Isolation of the low-molecular-mass form of catechol O-methyltransferase from rat liver and immunocytochemical localization of the enzyme in the glycogen compartment.

The low-molecular-mass form of two distinct catechol O-methyltransferase activities (S-adenosyl-L-methionine: catechol O-methyltransferase, COMT, EC 2.1.1.6) has been purified to homogeneity from rat liver using 40-70% ammonium sulfate precipitation, gel filtration on Sephadex G-100, adsorption on hydroxyapatite C and ion-exchange chromatography on DEAE-Sepharose CL-6B. The relative molecular mass Mr, determined by sodium dodecyl sulfate/polyacrylamide gel electrophoresis is 22 400 +/- 500. Irradiation of the enzyme in the presence of 8-azido-[methyl-3H]AdoMet results in the specific labeling of the catalytic site of the enzyme. Photolabeling was successful with crude COMT preparations and with the isolated enzyme. Immunocytochemical studies present new information about the localization of the low-molecular-mass form in the liver parenchyma. Subcellularly COMT immunoreactivity could be attributed exclusively to the compartment with glycogen granules. Nucleus, mitochondria and endoplasmic reticulum showed no immunostaining.

Antibody Specificity↗
PubMed1986

Oscillometry and direct blood pressure: a comparative clinical study during deliberate hypotension.

Oscillometry using an automatic monitor was compared with invasive blood pressure monitoring in 21 patients scheduled for surgery under general anaesthesia with deliberate hypotension. Six ranges of mean blood pressure measurements were studied, two of which were hypotensive. An excellent correlation was found between the two methods (systolic: r = 0.94; mean: r = 0.93; diastolic: r = 0.88) but there was a large variability among individual subjects. For systolic, diastolic and mean intra-arterial readings above an approximative value of 10.64 KPa (80 mmHg), the oscillometric monitor was found to underestimate blood pressure. Inversely, it was found to overestimate blood pressure for intra-arterial readings under the approximative value of 10.8 KPa (80 mmHg). We conclude that the non-invasive monitor represents a good trend estimation of the invasive radial blood pressure technique, but that wide inter-individual variability and the overestimation of blood pressure below an approximative value of 10.64 KPa (80 mmHg) precludes interchange of techniques when absolute values are considered, especially during controlled hypotension. However, oscillometry could represent a better estimate of central aortic pressure.

Adult↗
PubMed1986

The sleep apnoea syndrome and epidural morphine.

A patient not known in advance to have the sleep apnoea syndrome (SAS) was administered a combined epidural-general anaesthetic for a proposed radical prostatectomy. After surgery which had to be discontinued due to extensive tumoural spread, morphine 5 mg was administered through the epidural catheter for analgesia. Severe respiratory depression occurred eight hours later and was successfully reversed by repeated injections of naloxone. The potential danger of epidural morphine administration to SAS patients is discussed.

Aged↗
PubMed1986

The organization of the araBAD operon of Escherichia coli.

The nucleotide (nt) sequence of the araBAD operon of Escherichia coli B/r has been determined. The nt sequence predicts a transcript of about 4250 nt. The coding regions of araB, araA and araD genes were identified by partial amino acid (aa) sequences of the purified proteins and their cleavage products. We have deduced that the polypeptides encoded by the araBAD operon consist of 566 (araB), 500 (araA) and 231 (araD) aa residues. The operon contains a leader sequence of 27 nt. The intergenic region between araB and araA is 10 bp in length, while the araA and araD genes are separated by 283 bp consisting primarily of six REP sequences. Comparison of the E. coli sequence with that of Salmonella typhimurium [Lin et al., Gene 34 (1985) 111-122; 123-128; 129-134] shows that, while considerable divergence in nt sequence has occurred, the aa sequences are largely conserved. The most pronounced difference, found in the araD gene, is the deletion of a single nt in the S. typhimurium sequence.

Amino Acid Sequence↗
PubMed1986

In-vitro activity of ciprofloxacin, ceftriaxone and five other antimicrobial agents against 95 strains of Brucella melitensis.

We studied the in-vitro activity of seven antibiotics against 95 strains of Brucella melitensis isolated in blood cultures of 95 patients with brucellosis. The minimum inhibitory concentration (MIC) was measured by the agar dilution method. All strains of B. melitensis were inhibited by doxycycline at 0.25 mg/l, tetracycline at 0.5 mg/l, ciprofloxacin at 0.5 mg/l, streptomycin at 1 mg/l, ceftriaxone at 1 mg/l, rifampicin at 4 mg/l and by co-trimoxazole at 0.5/9.5 mg/l. We did not find strains resistant to any of the antibiotics studied. All antibiotics, including ciprofloxacin and ceftriaxone, showed a good in-vitro activity against B. melitensis.

Anti-Bacterial Agents↗
PubMed1986

Use of a controlled duodenal fistula in the management of a major duodenal injury.

The management of a major duodenal injury associated with gross peritoneal contamination caused by multiple colonic perforations is reported. Resection of devitalized duodenum with creation of a controlled duodenal fistula, a jejunostomy and three colostomies, together with subsequent reconstruction, led to a successful outcome.

Catheters, Indwelling↗
PubMed1986

Advances in single-chamber pacemaker diagnostic data.

Diagnostic data, which is Holter-type information documenting the pulse generators' interaction with the patient over time, are now available in single chamber pulse generators from at least six manufacturers. Diagnostic data are available in bradycardia, tachycardia, and rate-responsive pulse generators. Six hypothetical examples discuss the clinical utility of advanced diagnostic data. Three examples examine the use of diagnostic data with bradycardia pulse generators. These use rate histograms or high-rate counters to solve programming and patient problems. Two examples involve antitachycardia pulse generators and the uses for diagnostic data in both chronic and acute cases. One example deals with the use of maximum and minimum temperature diagnostics in proper programming of a temperature rate-responsive device.

Arrhythmias, Cardiac↗
PubMed1986

Mapping and complementation studies of the gene for release factor 1.

In Escherichia coli the release factor 1 protein (RF1) recognizes and terminates translation at UAG and UAA codons. Using the technique of ColE1 plasmid integration in polA strains, we have mapped the cloned gene for RF1 to 27 min on the E. coli chromosome. This is the same location as that of the uar gene in which temperature-sensitive mutations increase the suppression of UAG and UAA alleles. In this study we proved that the uar mutation lies in the gene for RF1 by complementation of the uar phenotype with plasmids carrying the RF1 gene and by cloning the uar allele onto the RF1 plasmid by means of homologous recombination. In addition, complementation and P1 mapping data suggest that sueB is also a mutation in the same position as the RF1 gene. We propose that the gene for RF1 be named prfA after protein release factor.

Alleles↗
PubMed1986

Comparison of Rapid NFT system and conventional methods for identification of nonsaccharolytic gram-negative bacteria.

This study examined the Rapid NFT system (Analytab Products, Plainview, N.Y.) to determine its ability to accurately identify 229 clinical isolates of mostly nonsaccharolytic gram-negative rods. Identifications were classified by the following scheme: correct (corresponding to excellent, very good, good, or acceptable identification as listed in the code book); low discrimination (correct identification among a range of listed possibilities, with additional tests necessary for accurate identification); incorrect. Correct identification was considered correct to species and subspecies for all organisms except Alcaligenes faecalis and "Alcaligenes odorans"; "A. faecalis/odorans" was considered a correct response. By using these criteria, 71.6% of the strains were correctly identified, 17.9% were identified with low discrimination, and 10.5% were incorrectly identified. When consideration was made for incorrect identification resulting from taxonomic problems (e.g., Alcaligenes and Moraxella spp.), incorrect identifications fell to 5.2%. The Rapid NFT system was truly rapid and was easy to use and interpret. Its use of carbon substrate assimilation enables it to provide more accurate identification of medically important nonsaccharolytic bacteria than do other commercially available systems.

Alcaligenes↗
PubMed1986

Late pericardial tamponade and coronary arteriovenous fistula after trauma.

A 48 year old man presented with cardiac tamponade six weeks after an apparently minor penetrating chest injury. Thoracotomy showed a haemopericardium with no actively bleeding vessel. Re-investigation eleven months later, prompted by persistent chest pain, showed the presence of a fistula between the second diagonal of the left anterior descending coronary artery and a cardiac vein.

Arteriovenous Fistula↗