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Biomedical subjects

M J Jordan

Publications and source records attributed to M J Jordan.

12 recordsLinked to original sources
PubMed2006

Effect of thyme essential oils (Thymus hyemalis and Thymus zygis) and monensin on in vitro ruminal degradation and volatile fatty acid production.

The effect of the essential oils of thyme on the in vitro ruminal degradability of a barley seed/alfalfa hay substrate was studied. Two essential oils were used, one from Thymus hyemalis (TH), rich in carvacrol, and the other from Thymus zygis (TZ), rich in thymol. Four experimental treatments of in vitro degradability, using the Daisy II(200/220) incubator, were conducted including a negative control (CO), a positive control at 7.5 microg/mL of monensin (MO), and two treatments with essential oils (TH or TZ) at 1.35 microL/mL. The material was incubated at 39.5 degrees C for various lengths of time. At each time, the disappearance of dry matter, crude protein, and neutral detergent fiber was measured. Volatile fatty acids (VFAs) were determined after 48 h of incubation. CO and MO provided (p < 0.01) higher values of potential degradability (a + b) of DM than the TH and TZ treatments (72.6 and 70.8 vs 53.2 and 48.2%, respectively). Also, crude protein degradability was lowest in the essential oil treatments. The CO treatment showed the highest potential degradability of NDF. The values of VFA production obtained (p < 0.001) with CO and MO treatments were higher than those obtained with TH and TZ treatments (21.0 and 19.1 vs 11.2 and 10.1 mM). The essential oils decreased the molar proportion of propionate, increasing the acetate/propionate ratio. In conclusion, the effects of essential oils at assayed doses would not be nutritionally beneficial to the ruminal energetic metabolism.

Animals↗
PubMed1991

Intraoperative assessment of atracurium-induced neuromuscular block using double burst stimulation.

Paired train-of-four (TOF) and double burst stimuli (DBS) were administered to the ulnar nerve at the wrist in 25 patients (group 1) paralysed with atracurium 0.5 mg kg-1; responses were measured mechanically (except every third DBS response which was manually evaluated). Another 30 patients (group 2) received a DBS every 60 s. A post-tetanic count (PTC) was performed when the first response (D1) was palpated. There was a significant correlation between the twitch heights of the first TOF response (T1) and D1 and likewise between the twitch heights of both second responses (r = 0.9; P less than 0.001), but there was a significant difference in regression coefficients of these two correlations (P less than 0.001). D1 was palpable first with a median PTC of 7. Our results showed that palpation of a single response implied a satisfactory level of paralysis. DBS may be useful for intraoperative clinical monitoring of neuromuscular block.

Adolescent↗
PubMed1991

Clinical approach to treatment of otitis media.

The author presents his experience of 10 years of practice with the treatment of otitis media. He expresses concern for the inconsistencies between articles written recommending treatment protocols for otitis media and actual clinical results from using those treatment protocols. Otitis media varies in its appearance from patient to patient, with its association to other continuous structures and other organ systems making it a challenging disease to correct and cure. Treatment must be tailor-made to fit the patient, and the physician needs to consider other professional opinions and emphasize follow-up care.

Child↗
PubMed1987

Neural control of internal anal sphincter function.

The effect on anal tone of electrical stimulation of the presacral (hypogastric) sympathetic nerves has been studied in eight patients during abdominal rectopexy or restorative proctocolectomy. A sharp fall in anal pressure occurred in seven patients (mean fall 59 cmH2O; range 35-80 cmH2O). In one patient given a beta- and alpha-sympathetic blocking drug (labetalol 200 mg) intra-operatively, the anal pressure decreased by 15 cmH2O. These observations show that stimulation of the presacral sympathetic nerves causes relaxation of the internal anal sphincter and implies that these nerves may induce relaxation of the sphincter in vivo. The pathway of the recto-anal reflex has been studied intra-operatively in three patients undergoing rectal excision. The recto-anal reflex is present after presacral nerve blockade and after full mobilization of the rectum, but is abolished by circumferential rectal myotomy. The reflex has a local intramural pathway. This observation validates the assumption that absence of this reflex is a feature of aganglionosis, as in Hirschsprung's disease.

Adrenergic Fibers↗
PubMed1981

Closed-circuit halothane and enflurane using an in-circle Goldman vaporizer.

A closed-circle absorber system incorporating an in-circle Goldman vaporizer was used to administer halothane or enflurane in oxygen to adult patients. The attained inspired and end-tidal concentrations of volatile agent after a period of stabilization at each vaporizer setting were measured by mass spectrometry. During spontaneous respiration under halothane the ranges of inspired concentrations at settings 1, 11/2 and 2 were respectively 0.5-0.9%, 1.4-2.4% and 3.3-4.5%. corresponding inspired enflurane concentrations at the same settings were 0.8-1.4%, 1.9-2.8% and 3.7-5.0%. IPPV to 5% end-tidal carbon dioxide, although increasing the inspired concentrations slightly, produced considerable increases in end-tidal concentrations. Minimal pre-oxygenation was used to assess the problem of nitrogen accumulation within the circuit. The maximum nitrogen concentration was 56%.

Adult↗
PubMed1979

Cimetidine in the prevention of the pulmonary acid aspiration (Mendelson's) syndrome.

Cimetidine 200 mg was given i.v. 1 h before induction of anaesthesia to 20 patients about to undergo emergency surgery. There was an increase in pH of gastric aspirate in all patients (P less than 0.001) and in 80% pH was greater than 2.5 units at the time of induction of anaesthesia. The pH of gastric aspirate continued to increase after induction of anaesthesia and was greater than 4 units in all patients at the time of tracheal extubation and in the early recovery period.

Adolescent↗
PubMed1978

Potency of mixtures of general anaesthetic agents.

The anaesthetic potencies of binary mixtures of the gases argon (Ar), nitrous oxide (N2O) and sulphur hexafluoride (SF6) have been measured using mice. The mixtures SF6-N2O and N2O-Ar showed additive behaviour, whereas the constituents of the mixture SF6-Ar were non-additive, having a smaller total potency than expected. Further experiments on this mixture with Italian Great Newts and on the carbon tetrafluoride mixtures CF4-Ar and CF4-SF6 with mice suggested that the anomalous potencies may arise from specific pulmonary effects associated with the breathing of SF6 accompanied by a high pressure of some other gas.

Anesthesia, Inhalation↗
PubMed1975

Effects of zinc-smelter emissions on forest soil microflora.

Within 2 km of a zinc (Zn) smelter in Palmerton, Pennsylvania, near the Lehigh Water Gap, up to 13.5% Zn by weight has been measured in the O2 horizon of the soil, and up to 8% Zn in the A1 horizon. The total numbers of bacteria, actinomycetes, and fungi (measured by dilution plate counts) were greatly reduced in the most severely Zn-contaminated soils compared with control soils. The reduction of microbial populations may be a partial cause of the decreased rate of litter decomposition at Lehigh Gap. Growth of most bacteria from control sites was reduced by 100 to 200 muM Zn, most actinomycetes by 100 muM Zn, and most fungi by 100 to 1000 muM Zn in thin-Pablum extract agar (TPab). All the tested actinomycetes and non-spore-forming bacteria isolated from Zn-contaminated Lehigh Gap soils were Zn-tolerant, growing normally in media containing 600-2000 muM Zn. Most fungi, regardless of source, were capable of at least 50% of normal growth at 700 muM Zn. Zinc-tolerant bacteria, actinomycetes, and fungi were readily isolated from low-Zn soils, suggesting that selection for Zn tolerance may proceed rapidly. Acidophilic Mortierella species have been selectively eliminated near the smelter, apparently because of elevated soil pH. Peryronellaea glomerata (Corda) Goidanich and Coniothyrium spp. were found only in the high-Zn soils.

Actinomycetales↗