PubMed Health⌕ Search

Biomedical subjects

N P Hudson

Publications and source records attributed to N P Hudson.

15 recordsLinked to original sources
PubMed2001

In vitro microelectrode study of the electrical properties of smooth muscle in equine ileum.

Intracellular microelectrode recordings were made from smooth muscle cells in cross-sectional preparations of equine ileum, superfused in vitro. Membrane potential oscillations and spike potentials were recorded in all preparations, but recordings were made more readily from cells in the longitudinal muscle layer than from cells in the circular layer. The mean (se) resting membrane potential (RMP) of smooth muscle cells in the longitudinal muscle layer was -51.9 (1.2) mV, and the membrane potential oscillations in this layer had a mean amplitude of 4.8 (0.4) mV, a frequency of 9.0 (0.1) cycles per minute and a duration of 5.8 (0.2) seconds. The membrane potential oscillations were preserved in the presence of tetrodotoxin. A waxing and waning pattern of membrane potential oscillation activity was observed. Nifedipine abolished the spiking contractile activity of the smooth muscle, did not abolish the membrane potential oscillations but did alter their temporal characteristics.

Action Potentials↗
PubMed2001

Treatment of systemic lupus erythematosus with LJP 394.

OBJECTIVE: LJP 394 is a novel therapy under development for the treatment of systemic lupus erythematosus (SLE). We investigated the optimal LJP 394 dosing regimen required to maximally reduce serum dsDNA antibodies. We also evaluated the safety and tolerability of repeated doses of LJP 394 as well as the effects of therapy on SLE related disease activity and health related quality of life. METHODS: This was a multicenter, partially randomized, placebo controlled, double blind, dose-ranging trial. Study drug or placebo was administered at weekly, biweekly, or monthly intervals for a total of 17, 9, or 5 doses, respectively. Fifty-eight patients were randomly assigned to receive 1, 10, or 50 mg LJP 394 or placebo. After a 2 month pretreatment period, dosing visits continued for 16 weeks, after which there was a 2 month posttreatment period. RESULTS: The greatest reductions in mean dsDNA antibody titers were observed in the group of patients who received 50 mg LJP 394 weekly (38.1% and 37.1 % at Weeks 16 and 24, respectively). A reduction (29.3%) in dsDNA antibody titers was also observed at Week 24 in the group of patients who received 10 mg LJP 394 weekly. The frequencies of adverse events were comparable in the placebo and active treatment groups. CONCLUSION: This clinical trial, in which a large number of patients with SLE were treated with LJP 394, expanded the safety profile of LJP 394 and demonstrated its capacity to reduce dsDNA antibodies.

Adolescent↗
PubMed2000

Tissue culture of the enteric nervous system from equine ileum.

Ileal samples were harvested fresh from euthanized adult horses. The tissues were microdissected to prepare wholemount preparations for immunohistochemistry and for either explant or dissociated culture systems of the enteric nervous system. Explant culture systems were established using whole-mounts of either the submucous plexus or the muscularis externa (including the myenteric plexus). Dissociated cell cultures could only be obtained from the submucous plexus. Culture systems were maintained for up to 5 days. Immunoreactivity for a neuronal marker (Pan-N) and for glial cell markers (GFAP and S100) indicated the presence of both neurons and enteric glia in the tissue culture preparations. This is the first report of equine enteric neurons being grown in tissue culture Further refinements to the techniques will be required before this in vitro model can be used for quantitative analysis.

Animals↗
PubMed1999

An immunohistochemical study of interstitial cells of Cajal (ICC) in the equine gastrointestinal tract.

The interstitial cells of Cajal (ICC) are c-kit immunoreactive cells of the gastrointestinal tract which are suggested to have a role in the control of intestinal motility. Cells with c-kit immunoreactivity have not been previously described in the gastrointestinal tract of the horse. Immunoreactivity for c-kit was revealed using immunohistochemical labelling with an anti-c-kit polyclonal antibody. Sections of normal gastrointestinal tissue were examined from 13 anatomically defined sites from stomach to small colon taken from horses free from gastrointestinal disease. Three types of c-kit immunoreactive cells were identified: spindle-shaped cells in the region of the myenteric plexus, stellate or bipolar cells in the circular muscle layer, and round cells in the submucosa. The round cells were shown to be mast cells with the use of toluidine blue staining, whereas the other c-kit immunoreactive cells did not exhibit metachromasia and were classified as ICC. This study will serve as a basis for future pathological studies in the horse.

Animals↗
PubMed1999

Primary hypoparathyroidism in two horses.

Two Thoroughbred horses were presented with various clinical signs which included sweating, agitation, muscle twitching and synchronous diaphragmatic flutter. These signs were associated with profound hypocalcaemia. A diagnosis of primary hypoparathyroidism was made on the basis of low serum ionised calcium concentration, hyperphosphataemia and markedly reduced serum immunoreactive parathyroid hormone concentrations in the presence of normal renal function. Treatment with a combination of intravenous calcium and subsequently oral calcium, magnesium and a vitamin D analogue (dihydrotachysterol) for up to 65 days resulted in complete remission of clinical signs. Horse 1 was euthanased 12 months after the initial recognition of signs. Results of necropsy were unremarkable apart from an absence of detectable parathyroid tissue. Horse 2 returned to athletic activities while receiving only maintenance doses of oral calcium carbonate.

Animals↗
PubMed1992

Comparison of azathioprine, methotrexate, and the combination of both in the treatment of rheumatoid arthritis. A controlled clinical trial.

OBJECTIVE: To compare the relative safety and efficacy of azathioprine (AZA), methotrexate (MTX), and the combination of both in the treatment of active rheumatoid arthritis (RA). METHODS: Two hundred twelve patients with active RA were entered into a 24-week prospective, controlled, double-blind, multicenter trial and were randomly assigned to 1 of 3 treatment groups. RESULTS: One hundred fifty-eight patients finished 24 weeks of the study. There were no remissions seen but response rates were greater than 30% for all outcome measures. Combination therapy was not statistically superior to MTX therapy alone, but both combination therapy and MTX alone were superior to AZA alone when patients were analyzed by intent-to-treat and with withdrawals treated as therapy failures. If only patients who continued taking the therapy were analyzed, the mean improvement was greater for AZA therapy than for MTX, while the combination remained the most active. Adverse effects on the gastrointestinal tract and elevations of liver enzyme levels were the most frequent causes for discontinuations. CONCLUSION: Both combination therapy and MTX alone were superior to therapy with AZA alone for active RA but were not statistically different in their effect on outcome assessment.

Adult↗
PubMed1991

When to suspect connective tissue disease.

When a connective tissue disease is suspected, physical and historical data should be collected to build a case for a clinical syndrome. Negative serologic results may be helpful; positive ones must be used with awareness of their limitations. If a diagnosis is not clinically evident or serologically confirmed, observation may be preferable to overdiagnosis and unnecessary treatment. If the syndrome is atypical, physicians should look for evidence of clinical overlap and reevaluate regularly with an open mind.

Connective Tissue Diseases↗
PubMed1988

Update: treatment of rheumatoid disease.

The treatment of rheumatoid arthritis is, of necessity, highly individualized and thus invites the full application of the art of medicine. Patient education, physical therapy, NSAIDs, DMARDs, and surgical therapy all potentially play a role in the management of this syndrome. Careful and repeated assessment of signs and symptoms will identify patients who are likely to benefit from the wide array of helpful but imperfect drugs currently in use. The availability of increasingly effective therapy means that early referral and treatment are more important than ever in treatment of rheumatoid arthritis.

Anti-Inflammatory Agents, Non-Steroidal↗