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C Prior

Publications and source records attributed to C Prior.

At least 91 records · Page 5Linked to original sources
PubMed1989

Interferon in lungs.

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Bronchoalveolar Lavage Fluid↗
PubMed1989

[Is percutaneous liver biopsy using the Trucut (Travenol) needle superior to Menghini puncture?].

The aim of this study was to compare the quality of biopsy cylinders obtained by the Menghini or Trucut liver biopsy-method as well as the frequency of complications observed with both these methods. For this purpose, 74 Menghini and 62 Trucut biopsies were analyzed. Both groups were comparable with respect to histologic diagnosis, but no final diagnosis could be made in eight cases of Menghini biopsy because of insufficiency of the material obtained. Fragmentation of the sample occurred significantly more often in the Menghini group (p less than 0.05; chi 2 test). Trucut biopsies were significantly longer (12 mm versus 8 mm mean value; p less than 0.001; Wilcoxon rank sum test) and contained significantly more portal tracts (16 versus 6 mean value; p less than 0.001). None of the total 136 biopsies led to serious complications. We conclude that Trucut liver biopsy is superior to the Menghini method since tissue yield is better and both methods are equally safe.

Adolescent↗
PubMed1988

Urinary neopterin excretion in pulmonary sarcoidosis: correlation to clinical course of the disease.

Urinary neopterin levels were determined by high pressure liquid chromatography in 36 patients with pulmonary sarcoidosis. Values were above normal range in 69.4% of all patients. Neopterin excretion was significantly higher in radiologic types II/III than in type I disease (p = 0.0265, Mann-Whitney U-test). Urinary neopterin showed a weak, but significant inverse correlation to disease duration (r = -0.36; p = 0.034, Spearman's rank correlation). No significant correlation could be found between neopterin and the presence of pulmonary or extrapulmonary symptoms, vital capacity, forced expiratory volume in the first second, steroid treatment, and serum angiotensin converting enzyme. Follow-up studies revealed that worsening or improvement of chest X-ray findings was invariably accompanied by rising or decreasing neopterin excretion, respectively. Patients with normal neopterin at initial evaluation had a higher tendency towards spontaneous healing, and none of them deteriorated during the follow-up period. We conclude that urinary neopterin excretion reflects one aspect of alveolitic "activity" in pulmonary sarcoidosis and that normal values probably indicate a favorable prognosis.

Adult↗
PubMed1988

IOL prediction: an evaluation of preoperatively determined intraocular lens power accuracy.

A retrospective survey of 612 eyes that had undergone cataract extraction and IOL implantation was undertaken to evaluate the accuracy of ultrasound biometry combined with keratometry using the SRK regression formula, for the preoperative prediction of intraocular lens powers. A mean error of +0.35 dioptre sphere (DS) (SD +/- 0.98) was found for the series overall, with a significant (P less than 0.005) difference between the distribution of postoperative refractive errors using the S.R.K. formula for IOL prediction and the use of a standard lens of 19.5 DS. The consistency of results was tested for those patients with greater or less than normal axial length. Linear regression analysis showed no correlation between axial length and postoperative refractive error and therefore does not support the adjustment of predicted IOL powers by a factor based on axial length. Statistically significant differences were found between surgeons' results, supporting the practice of A-constant modification for individual surgeons.

Cornea↗
PubMed1988

A further study of the neuromuscular effects of vesamicol (AH5183) and of its enantiomer specificity.

1. The effects of vesamicol (2-(4-phenylpiperidino) cyclohexanol), an inhibitor of acetylcholine storage, and its two optical isomers have been studied on neuromuscular transmission in rat and frog muscle, and on nerve conduction in frog nerve. 2. Racemic vesamicol produced a pre-block augmentation of twitch tension that also occurred in directly-stimulated muscle. This effect is thus at least partially due to an increase in muscle contractility. 3. (-)-Vesamicol was approximately 20 times more potent than (+)-vesamicol in blocking twitches elicited at 1 Hz. This degree of stereoselectivity is similar to that measured for inhibition of acetylcholine uptake by isolated synaptic vesicles. Both enantiomers were equally weak in reducing nerve action potential amplitude in frog nerve. 4. Further studies with the active isomer, (-)-vesamicol, showed that, like that produced by racemic vesamicol, the neuromuscular block was highly frequency-dependent. The block was not reversed by choline or neostigmine, but was partially reversed by 4- or 3,4-aminopyridine. 5. Preliminary electrophysiological studies showed that vesamicol reduced miniature endplate potential amplitude in rapidly-stimulated frog nerve-muscle preparations. Addition of lanthanum ions increased the frequency of miniature endplate potentials and led to the appearance of apparently normal-sized potentials amongst those of reduced amplitude. 6. The results show the close agreement between pharmacological and biochemical observations indicating the suitability of the rat diaphragm as a test model for substances of this nature. The degree of reversibility of the vesamicol-induced neuromuscular block by aminopyridines was unexpected, and it is suggested that in the presence of a drug which greatly increases release, a pool of acetylcholine is capable of being released which is not normally releasable after block of storage by vesamicol. It is also considered possible that the results from the intracellular recording studies may be explained in these terms.

Anesthetics, Local↗
PubMed1988

[Malacoplakia of the urinary tract].

Malacoplakia is a granulomatous disease that most frequently involves the genitourinary tract. Because of the great variability of symptoms and lack of typical radiologic findings, this disease is usually not considered preoperatively. Generally of benign nature in the lower urinary tract, it leads to destruction and loss of renal function when affecting ureter and kidney. Progression of the latter can only be prevented by surgical intervention. Malacoplakia of the lower urinary tract requires long-term treatment with intracellularly active antibiotics in combination with drugs enhancing phagocytosis.

Female↗
PubMed1987

Potential of urinary neopterin excretion in differentiating chronic non-A, non-B hepatitis from fatty liver.

Urinary neopterin excretion was measured in 26 patients with histologically proven chronic non-A, non-B hepatitis (16 chronic persistent hepatitis, 10 chronic active hepatitis) and in 16 patients with steatosis. The potential of neopterin levels to discriminate between the two patient groups was compared with that of standard laboratory variables. Neopterin levels and triglycerides were shown to be the best variables for discriminating between the hepatitis and fatty liver patients, neopterin being the more specific of the two. Neopterin excretion in chronic persistent hepatitis was not statistically different from that in chronic active hepatitis. In the absence of specific tests, increased neopterin excretion seems to be a useful marker for diagnosing chronic non-A, non-B hepatitis and particularly in differentiating it from fatty liver.

Adult↗
PubMed1987

Lambert-Eaton myasthenic syndrome: I. Early morphological effects of IgG on the presynaptic membrane active zones.

In the freeze-fractured presynaptic membrane of the motor end-plate, the active zones consist of two parallel arrays and each array contains 10- to 12-nm particles arranged in two rows. In the Lambert-Eaton myasthenic syndrome (LEMS) and in mice treated with 10 mg/day of LEMS IgG, administered intraperitoneally for several weeks, there was a paucity and disorganization of the active zones, and clusters of 10- to 12-nm particles appeared. To further define the changes in the active zones, mice were studied that had been treated over 2 days with 104 to 180 mg of IgG. Treatment transferred the physiological defect of LEMS. Control mice received normal human IgG or no IgG. The spacing and density (number/unit area) of active-zone particles were evaluated in presynaptic membrane P-faces using computer-assisted stereometry. In the normal active zone, the distance between particles in a given row and between adjacent rows of an array was less than, but the distance between the two arrays was greater than, the distance between the two antigen-binding sites on human IgG. In mice treated with LEMS IgG, the initial alteration in the active zone was a decrease in the distance between particles in a given row and between adjacent rows of an array; the distance between the two arrays remained unaltered. In more affected active zones, the parallel orientation of the rows was disturbed and the arrays became clusters. There was a significantly reduced density of active zones and of large-membrane particles associated with all active zones and clusters.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Waldenstrom macroglobulinaemia treated with sequential hemibody irradiation.

A 40-year-old man presented with symptoms of anaemia and blurred vision. Waldenstrom macroglobulinaemia was diagnosed on the basis of plasmacytoid lymphocytes in the peripheral blood, extensive bone marrow involvement, and an IgM kappa monoclone in the plasma of 48 g/liter. Symptoms were immediately reversed by isovolaemic continuous-flow plasmapheresis coupled with red cell transfusion. Specific therapy was undertaken with sequential hemibody irradiation. At two years of follow-up the patient enjoys excellent health, has improved haematopoietic reserve in the bone marrow, and the only therapy required is intermittent plasmapheresis to control symptoms relating to rising viscosity. Thus, systemic irradiation, which is well tolerated and objectively reduces marrow tumour bulk, offers an alternative to chemotherapy in the palliative management of active macroglobulinaemia and may diminish but not prevent the need for intermittent plasmapheresis.

Adult↗
PubMed1987

The effect of myasthenic syndrome antibody on presynaptic calcium channels in the mouse.

1. The action of immunoglobulin G obtained from patients with Lambert-Eaton myasthenic syndrome (LEMS IgG) was investigated by injecting mice, followed by intracellular recordings from the mouse diaphragm. 2. End-plate potential quantal content was studied over a range of Ca2+ concentrations. Curves of log quantal content versus log Ca2+ concentration were shifted to the right by LEMS IgG. For low Ca2+ concentrations, release continued to follow Poisson statistics after LEMS IgG treatment. 3. Miniature end-plate potential (m.e.p.p.) frequency was measured in solutions containing high K+ concentrations. LEMS IgG significantly reduced m.e.p.p. frequency at each K+ concentration studied. 4. M.e.p.p. frequency was measured at fixed high-K+ concentration (15.9 mM) for a range of Ca2+ concentrations. The log-log plot of m.e.p.p. frequency versus Ca2+ concentration was shifted downwards throughout by LEMS IgG. 5. M.e.p.p. frequency was not affected by LEMS IgG in Ca2+-free solutions (K+ concentration 15.9 mM) or in solutions of low Ca2+ concentration (K+ concentration 5.9 mM). 6. At each Ca2+ concentration studied, m.e.p.p. amplitudes were not affected by LEMS IgG. 7. The data suggest that LEMS IgG acts on presynaptic voltage-dependent Ca2+ channels to cause their loss of function, probably by down-regulation.

Action Potentials↗
PubMed1986

Urinary neopterin, a marker of clinical activity in patients with Crohn's disease.

Urinary neopterin excretion was measured in 34 patients with Crohn's disease. Neopterin excretion showed a significant correlation with disease activity using a clinical activity score. An interacting effect of previous medical or surgical therapy on neopterin excretion could be ruled out. Disease localization and extent did not exert any influence on neopterin excretion. Neopterin values were significantly correlated with disease duration, body weight and the presence of a palpable abdominal mass. Multiple stepwise regression analyses identified the combination of neopterin, hematocrit, weekly stool frequency, palpable abdominal mass and related symptoms as predicting clinical activity better than Crohn's Disease Activity Index (CDAI). Thus, neopterin determination may be introduced as an additional biochemical parameter in the assessment of disease activity.

Adolescent↗
PubMed1986

A simple index relating clinical activity in Crohn's disease with T cell activation: hematocrit, frequency of liquid stools and urinary neopterin as parameters.

Crohn's disease is characterized by alternating acute and quiescent periods. Several indices for activity of the inflammatory process have been proposed to have criteria for prognosis of the clinical course and therapeutic efficacy. Neopterin is specifically released from human monocytes-macrophages after induction by interferon-gamma secreted from activated human T lymphocytes. Thus, urinary neopterin excretion is elevated in diseases involving activation of cellular immunity. Fifteen clinical and laboratory parameters, including urinary neopterin levels, collected from 35 visits of patients with Crohn's disease, were compared using multiple linear regression analysis with a simple clinical activity index as reference. Prediction of clinical activity was best with the combination of hematocrit, weekly number of liquid stools and neopterin. A simple triple-parametric Crohn's disease activity index was established on the basis of this result. Its quality was tested on independent data obtained from 25 repeat visits of 13 of these patients. A comparison with the well-known Crohn's Disease Activity Index (CDAI) was performed. The results obtained with the proposed activity index were slightly better than those with the eight-parametric CDAI for the data from the first as well as from the repeat visits. We conclude that our simple index is a reliable and easily accessible measure for clinical activity in patients with Crohn's disease.

Adolescent↗
PubMed1986

The effects of chloramphenicol isomers on the motor end-plate nicotinic receptor-ion channel complex.

Four enantiomers of chloramphenicol have been tested for their effects on end-plate current and miniature end-plate current decay and amplitude characteristics in the voltage-clamped costocutaneous nerve-muscle preparation of the garter snake. All four enantiomers exhibited effects on end-plate current and miniature end-plate current decay at similar concentrations (0.2-1.0 mM), indicating that the measured effect was not related to the antibacterial action of the compounds in which D-threo chloramphenicol is known to be at least 50 times more powerful than the L-threo and D- and L-erythro isomers. The compounds slightly increased end-plate current but not miniature end-plate current amplitude, indicating that they produce an increase in end-plate current quantal content. This effect was verified by an analysis of end-plate current driving functions (see Appendix) for one of the chloramphenicol isomers. In addition to this presynaptic action, all four compounds converted end-plate current and miniature end-plate current decays from single to double exponential functions. This effect was both concentration and voltage dependent. For all four compounds, hyperpolarization resulted in a progressive decrease in tau f and an increase in tau s. The relative amplitudes of the fast and slow decay components were independent of membrane potential. The results are interpreted in terms of the drugs blocking the open form of the acetylcholine-activated receptor-ion channel complex. However, in addition to affecting decay characteristics, all four compounds increased the charge passed during both end-plate and miniature end-plate currents. This effect was concentration but not voltage dependent and is inconsistent with the predictions of the sequential model for open ion channel blockade. By using an extension of Ruff's analysis of the sequential model of open end-plate ion channel blockade, we have been able to show that the action of the chloramphenicols on end-plate current amplitude and time course can be explained by the combination of two distinct mechanisms. First is an open channel block conforming to the sequential model and with calculated channel blocking affinity constants ranging from 0.3-1.0 mM. The channel blocking actions of all four isomers were shown to be independent of membrane voltage. Second is an action to slow channel closing, resulting in prolonged open time and hence increased charge passed during the end-plate current. This effect was strongly concentration dependent, but not voltage dependent.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗