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J H Jones

Publications and source records attributed to J H Jones.

At least 19 recordsLinked to original sources
PubMed2006

Combined ultrasound and isotope scanning is more informative in the diagnosis of congenital hypothyroidism than single scanning.

BACKGROUND: Thyroid imaging is helpful in confirming the diagnosis of congenital hypothyroidism and in establishing the aetiology. Although isotope scanning is the standard method of imaging, ultrasound assessment may be complementary. AIM: To determine the strengths and weaknesses of thyroid ultrasound and isotope scanning in neonates with thyroid stimulating hormone (TSH) elevation. METHODS: Babies from the West of Scotland with raised capillary TSH (>15 mU/l) on neonatal screening between January 1999 and 2004 were recruited. Thyroid dimensions were measured using ultrasonography, and volumes were calculated. Isotope scanning was carried out with a pinhole collimator after an intravenous injection of 99m-technetium pertechnetate. RESULTS: 40 infants (29 female) underwent scanning at a median of 17 days (range 12 days to 15 months). The final diagnosis was athyreosis (n = 11), ectopia (n = 12), hypoplasia (n = 8; 3 cases of hemi-agenesis), dyshormonogenesis (n = 5), transient hypothyroidism (n = 2), transient hyperthyrotropinaemia (n = 1) and uncertain status with gland in situ (n = 1). 6 infants had discordant scans with no isotope uptake but visualisation of thyroid tissue on ultrasound. This was attributed to TSH suppression from thyroxine (n = 3); maternal blocking antibodies (n = 1); cystic degeneration of the thyroid (n = 1); and possible TSH receptor defect (n = 1). CONCLUSIONS: Isotope scanning was superior to ultrasound in the detection of ectopic tissue. However, ultrasound detected tissue that was not visualised on isotope scanning, and showed abnormalities of thyroid volume and morphology. We would therefore advocate dual scanning in newborns with TSH elevation as each modality provides different information.

Congenital Hypothyroidism↗
PubMed2006

Improvement in screening performance and diagnosis of congenital hypothyroidism in Scotland 1979-2003.

AIM: To assess the Scottish newborn screening programme for congenital hypothyroidism from 1994 to 2003 (period 2) for performance and compare with an initial audit covering 1979 to 1993 (period 1). DESIGN: Performance data-age at blood spot sampling, notification by screening laboratory, start of treatment, and the prevalence of late testing, notification or treatment-were compared, together with the incidence of congenital hypothyroidism. RESULTS: Comparing data for period 2 with period 1, the mean annual incidence of true congenital hypothyroidism was 1:3655 live births v 1:4363. Median age for Guthrie sampling (all referrals) was 6 v 7 days (p<0.0001). Late sampling (>10 days) had fallen from 10.7% to 7%. For infants requiring repeat sampling before notification, the median (range) interval between initial and final repeat samples was 11 (1 to 52) compared with 14 (3 to 73) days. Median age at notification for true congenital hypothyroidism was 10 v 12 days (p <0.0001). Late notification (>15 days) was justifiable (mild TSH elevation) in 10 of 13 patients in period 2. Median age at start of treatment for true congenital hypothyroidism had improved to 11 days from 13.5 days. For true congenital hypothyroidism, late treatment (>16 days) occurred in 7% of patients compared with 19% (p<0.0001). CONCLUSIONS: There has been an improvement in performance measures for the congenital hypothyroidism screening programme in Scotland. However, late sampling, occurring primarily in inpatients and which is never justified, remains a problem, while the interval between initial and recall sampling is a further source of delay.

Age Factors↗
PubMed2003

Mucociliary transport determined by in vivo microdialysis in the airways of normal and CF mice.

We report a novel method to measure mucociliary transport (MCT) in both the upper and lower airways of normal and CF mice. The in vivo microdialysis technique involves placing a small quantity of dye on the airway surface and a microdialysis probe a defined distance from the site of dye deposition. The dye is transported toward the probe by ciliary transport and, upon reaching the microdialysis probe, diffuses across the dialysis membrane and is collected in the dialysate leaving the probe. The rate of MCT is calculated from the length of time from dye deposition to recovery. The rate of tracheal MCT in normal mice was 2.2 +/- 0.45 (SE) mm/min (n = 6), a value similar to that in reports using other techniques. MCT in CF mice was not different (2.3 +/- 0.29, n = 6), consistent with previous observations suggesting that tracheal ion transport properties are not different between CF and normal mice. The rate of MCT in the nasal cavity of normal mice was slower than in the trachea (1.3 +/- 0.26, n = 4). MCT in the CF mouse nasal cavity (1.4 +/- 0.31, n = 8), a region in which the CF mouse exhibits bioelectric properties similar to the human CF patient, was, again, not different from the normal mouse, perhaps reflecting copious gland secretion offsetting Na(+) and liquid hyperabsorption. In conclusion, we have developed a versatile, simple in vivo method to measure MCT in both upper and lower airways of mice and larger animals.

Animals↗
PubMed2002

Physiological responses of young Thoroughbreds during their first year of race training.

Yearling horses are typically trained for more than a year before they begin racing; therefore, we questioned how relevant analyses of the initial responses to training are compared to physiological responses that occur over a year of training, and whether young horses with no history of training would respond the same as older horses that had been trained previously. We hypothesised that changes in O2 transport over the last months of a year of training would be different than at the beginning. We trained 5 yearling Thoroughbreds and evaluated metabolism, O2 transport and echocardiograms. Measurements were made before breaking (T1), after 6 months of training (T2) and following an additional 4 months of training (T3). We compared 5 trained horses (TR) with 5 untrained (UT) sex-, size- and age-matched yearlings kept at pasture and in boxes. Satellite telemetry indicated UT moved less total daily distance than TR during winter and more during summer, but UT walked for 80% of their distance, TR only 25%. The UT increased body mass (Mb) after T1 by 13% and were significantly heavier and fatter than TR. Specific aerobic capacity (VO2max/Mb) increased by 16% in both groups at T2, but by T3 was not different from T1 in UT, but was higher in TR (19%>T1, 15%>UT). In TR, specific cardiac output (Q/Mb) increased by 13% at T2, and specific stroke volume (V(S)/Mb) were larger at T2 and T3 than T1 and UT at the same times both by physiological (15-16%) and echocardiographical (22-23%) estimates. Increased Vs was a primary correlate of the sustained increase in VO2max/Mb in TR. The large increases in V(S) and VO2max had occurred by T2 and changed only slightly by T3.

Aging↗
PubMed2002

Does training affect mRNA transciption for cytokine production in circulating leucocytes?

Physical exertion is a stimulus for the upregulation of cytokine production including IL-1beta, IL-1ra, IL-2, IL-4, IL-6, IL-10 and TNF-alpha in horses. To investigate that hypothesis, we initiated training of 5 stall-rested Thoroughbreds. Blood samples were drawn before and weekly during training. The relative transcription of mRNA within the leucocytes was measured using real time TaqMan quantitative PCR. The training protocol was walking (3 min), trotting (3 min) and cantering/galloping (6 min) increasing in intensity weekly (6 to 12 m/s) and culminating in an intense exercise period. Comparisons of mRNA concentrations were made using a repeated measures ANOVA on ranks and a Student-Newman-Keuls pair-wise multiple comparison (P<0.05). The training programme or intense exercise bout did not affect IL-2, IL-4, IL-6 and IL-10. IL1-beta and TNF-alpha transcription increased on Day 23. TNF-alpha peaked on Day 23 and IL1-beta on Day 30. Neither demonstrated a response to intense exercise. IL-1ra decreased significantly on Day 9; rose significantly from Day 9 to Days 16 and 23; remained significantly elevated through Days 30 and 37 over Day 9, and rose very slightly after intense exercise on Day 56. Alterations in leukocyte cytokine responses may influence susceptibility to infectious disease, metabolic responses to exercise or exercised induced syndromes.

Analysis of Variance↗
PubMed2002

Heterogeneity of intrapleural pressures during exercise.

We determined whether the caudodorsal region of the intrapleural space in exercising horses experiences larger pressure fluctuations than other regions and whether systematic phase-shifting of peak intrapleural pressures along the length of the thorax suggests the existence of locomotor-induced intrapleural pressure waves. We utilised percutaneous introducers and solid-state pressure-tip transducers implanted along the dorsal aspect of the thorax, mid-thorax or oesophagus to measure regional intrapleural pressures while 3 horses galloped on a flat treadmill at 13-14 m/s, then recorded pressures from the same catheters when horses exercised intensely (heart rate 170-190 beats/min) while swimming with no ground concussion. Pressure excursions in the caudodorsal region did not vary systematically from other regions during galloping or swimming, nor more than a few torr between different locations. During swimming, peak expiratory pressures were higher than during galloping (68-79 vs. 26-32 torr), and horses breathed explosively at frequencies 5 times slower than while galloping (28 vs. 120/min). During galloping, individual catheter locations registered locomotor concussion; however, this was variable and did not indicate a systematic pressure wave passing through the lung or intrapleural space.

Animals↗
PubMed2001

Frequency of and risk factors for epistaxis associated with exercise-induced pulmonary hemorrhage in horses: 251,609 race starts (1992-1997).

OBJECTIVE: To determine the frequency of epistaxis during or after racing among racehorses and identify factors associated with development of epistaxis. DESIGN: Retrospective study. SAMPLE POPULATION: 247,564 Thoroughbred and 4,045 Anglo-Arab race starts. PROCEDURE: Race start information (breed, age, sex, racing distance, and race type) was obtained for Thoroughbred and Anglo-Arab horses racing in Japan Racing Association-sanctioned races between 1992 and 1997. All horses that raced were examined by a veterinarian within 30 minutes of the conclusion of the race; any horse that had blood at the nostrils was examined with an endoscope. If blood was observed in the trachea, epistaxis related to exercise-induced pulmonary hemorrhage (EIPH) was diagnosed. RESULTS: Epistaxis related to EIPH was identified following 369 race starts (0.15%). Frequency of EIPH-related epistaxis was significantly associated with race type, age, distance, and sex. Epistaxis was more common following steeplechase races than following flat races, in older horses than in horses that were 2 years old, following races < or =1,600 m long than following races between 1,601 and 2,000 m long, and in females than in sexually intact males. For horses that had an episode of epistaxis, the recurrence rate was 4.64%. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that frequency of EIPH-related epistaxis in racehorses is associated with the horse's age and sex, the type of race, and the distance raced. The higher frequency in shorter races suggests that higher intensity exercise of shorter duration may increase the probability of EIPH.

Age Factors↗
PubMed2001

Surfactant proteins in bronchoalveolar lavage fluid of horses: assay technique and changes following road transport.

An enzyme-linked immunosorbent assay (ELISA) was developed for equine surfactant proteins SP-A and SP-D in bronchoalveolar lavage fluid (BALF). Anti-equine SP-A or SP-D monoclonal antibodies (mAb) were produced by hybridoma technology, purified by the antibody purification reagent, and analysed by Western blotting analysis. The immunoreaction (two-site sandwich ELISA) with a mAb, peroxidase-labelled mAb and BALF sample was carried out simultaneously and analytical recovery and precision were assayed. Six mAb for SP-A and four mAb for SP-D were successfully cloned in limiting dilution to monoclonality. These mAb were reacted with equine SP-A or SP-D on Western blotting analysis. For SP-A, a combination of solid-phase TA08 and horseradish peroxidase (HRP)-conjugated WA28 was found to be more sensitive than other combinations, gave a good dose response and was capable of measuring 0.78 to 100 ng of protein/ml. For SP-D, a combination of solid-phase TD13 and HRP-conjugated WD19 was found to be more sensitive than other combinations, had a good dose response and was capable of measuring 0.78 to 200 ng of protein/ml. The assay was used to determine the effect of 41 hours of road transport on the concentrations of SP-A and SP-D in the BALF of 30 horses. The concentrations of SP-A and SP-D decreased by 55 per cent and 36 per cent, respectively, decreases similar to the decrease in phosphatidylglycerol concentration previously reported by the authors.

Animals↗
PubMed2001

Coats' disease.

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Adult↗
PubMed2000

Induction of Ca-independent PLA(2) and conservation of plasmalogen polyunsaturated fatty acids in diabetic heart.

Diabetes-induced changes in phospholipase A(2) (PLA(2)) activity have been measured in several tissues but are undefined in diabetic myocardium. We measured ventricular PLA(2) activity in control, streptozotocin-induced diabetic, and insulin-treated diabetic rats and characterized myocardial phospholipids to determine whether diabetes altered myocardial phospholipid metabolism. Increased membrane-associated Ca(2+)-independent PLA(2) (iPLA(2)) activity was observed in diabetes that was selective for arachidonylated phospholipids. Increased iPLA(2) activity was accompanied by an increase in choline lysophospholipids. Diabetes was associated with marked alterations in the phospholipid composition of the myocardium, characterized by decreases in esterified arachidonic and docosahexaenoic acids and increases in linoleic acid. The decrease in polyunsaturated fatty acids was confined to diacylphospholipids, whereas the relative amount of these fatty acids in plasmalogens was increased. Diabetes-induced changes in PLA(2) activity, lysophospholipid production, and alterations in phospholipid composition were all reversed by insulin treatment of diabetic animals. Diabetes-induced changes in membrane phospholipid content and phospholipid hydrolysis may contribute to some of the alterations in myocardial function that are observed in diabetic patients.

Animals↗
PubMed2000

Use of sevoflurane for anesthetic management of horses during thoracotomy.

OBJECTIVE: To evaluate sevoflurane as an inhalation anesthetic for thoracotomy in horses. ANIMALS: 18 horses between 2 and 15 years old. PROCEDURE: 4 horses were used to develop surgical techniques and were euthanatized at the end of the procedure. The remaining 14 horses were selected, because they had an episode of bleeding from their lungs during strenuous exercise. General anesthesia was induced with xylazine (1.0 mg/kg of body weight, IV) followed by ketamine (2.0 mg/kg, IV). Anesthesia was maintained with sevoflurane in oxygen delivered via a circle anesthetic breathing circuit. Ventilation was controlled to maintain PaCO2 at approximately 45 mm Hg. Neuromuscular blocking drugs (succinylcholine or atracurium) were administered to eliminate spontaneous breathing efforts and to facilitate surgery. Cardiovascular performance was monitored and supported as indicated. RESULTS: 2 of the 14 horses not euthanatized died as a result of ventricular fibrillation. Mean (+/- SD) duration of anesthesia was 304.9 +/- 64.1 minutes for horses that survived and 216.7 +/- 85.5 minutes for horses that were euthanatized or died. Our subjective opinion was that sevoflurane afforded good control of anesthetic depth during induction, maintenance, and recovery. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of sevoflurane together with neuromuscular blocking drugs provides stable and easily controllable anesthetic management of horses for elective thoracotomy and cardiac manipulation.

Anesthesia, General↗
PubMed1999

Im-trityl protection of histidine.

A rational attempt to prepare FmocHis(piTrt)OH regiospecifically gave in fact the well-known tau-trityl isomer, and experiments with model systems indicate that the prospects for access to pi-trityl histidine derivatives, which would be of great value for the racemization-free synthesis of histidine-containing peptides, are poor.

Histidine↗