Chronic unexplained hypertransaminasemia may be caused by occult celiac disease

In a subset of patients attending liver units, a chronic increase in serum transaminases may remain of undetermined cause despite thorough investigations. On the other hand, elevated levels of serum transaminases have been reported in about 40% of adult celiac patients. To evaluate the prevalence of subclinical celiac disease in patients with chronic unexplained hypertransaminasemia in comparison with that in the general population (0.5%), 140 consecutive patients with chronic increases of serum transaminases levels of unknown cause were tested for antigliadin and antiendomysium IgA antibodies. All patients with positive antibody tests were offered upper gastrointestinal endoscopy with distal duodenal biopsy. Thirteen patients (9.3%, 95% confidence interval 5. 0-15.4) had positive antigliadin and antiendomysium antibodies. The prevalence of antibodies was 17% in women and 5.4% in men (8/47 vs. 5/93 respectively; relative risk 3.2, 95% confidence interval 1.1-9. 1). Distal duodenal biopsy performed in all but one of the patients showed mild villous atrophy with increased intraepithelial lymphocytes in three cases, subtotal villous atrophy in six, and total villous atrophy in three. The prevalence of celiac disease in the patient group was significantly higher than that in the general population (P <.001) with a relative risk of 18.6 (95% confidence interval 11.1-31.2). On the basis of the present findings, screening for celiac disease is an important tool in the initial diagnostic work-up of patients with chronic unexplained hypertransaminasemia.

Serum von Willebrand factor levels in patients with inflammatory bowel disease are related to systemic inflammation

BACKGROUND

Increased levels of circulating von Willebrand factor (vWF) have been found in patients with inflammatory bowel disease (IBD); this increase may reflect either endothelial damage or systemic inflammation. Our aim was to evaluate serum vWF levels in patients with IBD and their correlation with clinical and biochemical disease activity.

METHODS

We evaluated serum vWF levels in 32 patients with ulcerative colitis (UC) (10 active with increased acute-phase reactants (APR), 6 active with normal APR, 16 in remission), 27 with Crohn disease (CD) (10 active, 12 quiescent, and 5 quiescent with increased APR), and 31 healthy controls.

RESULTS

Mean levels of vWF were 100.1 (standard deviation (s), 51.4) in IBD and 89.9 (s, 36.9) in controls (P = 0.33). Only five (8.47%) patients (three with active UC, one with active CD, and one with inactive CD but increased APR) showed circulating vWF levels higher than the upper limit of normal (150), compared with 1 (3.2%) of controls (P = 0.32). Among CD patients vWF levels were 80.0+/-25.4 in patients with quiescent disease and normal APR, 123.3+/-63.4 in patients with active disease (P = 0.04 versus inactive with normal APR), and 135.8+/-90.0 in patients with quiescent disease and increased APR (P = 0.059 versus inactive with normal APR). Among UC patients vWF levels were 82.7+/-35.6 in patients with quiescent disease and normal APR and 125.1+/-54.2 in those with active disease and increased APR (P = 0.002). Overall, mean vWF levels were significantly higher in patients with increased APR than in patients with normal APR (P = 0.0005) and controls (P = 0.009).

CONCLUSIONS

Our data show slight but significant increases in serum vWF levels in patients with IBD, which are correlated with signs of systemic inflammation.

[Topical beclomethasone dipropionate (BDP) in intestinal inflammatory diseases: the results of a multicentre trial]

The authors assessed the efficacy and tolerability of BDP in an open protocol using rectal enemas and suppositories and in a double-blind protocol vs mesalazine using rectal enemas. A total of 47 patients suffering from ulcerous rectocolitis were enrolled in the study and treated for 42 days while undergoing endoscopic, histologic and clinical controls. In conclusion, the authors affirm that BDP may represent a useful new therapeutic instrument in the treatment of slight to moderately severe forms of inflammatory intestinal disease.

A new mesalazine gel enema in the treatment of left-sided ulcerative colitis: a randomized controlled multicentre trial

BACKGROUND

A new mesalazine rectal gel preparation (without propellant gas) has been recently developed to improve topical treatment in distal ulcerative colitis.

AIM

To evaluate the efficacy, safety and patient tolerability of mesalazine gel enema compared with mesalazine foam enema in the treatment of patients with acute left-sided ulcerative colitis.

METHODS

In a randomized multicentre investigator-blind parallel group trial, 103 patients with mild to moderate left-sided colitis or proctosigmoiditis were randomly allocated to mesalazine 2 g gel enema (n = 50 evaluable patients) and mesalazine 2 g foam enema (n = 53 evaluable patients) for 4 weeks. Clinical symptoms, endoscopic and histological findings were assessed at entry, 2 and 4 weeks. Patients' evaluation of treatment tolerability and acceptability was assessed at 2 and 4 weeks.

RESULTS

After 4 weeks of treatment, clinical remission was achieved by 76% of mesalazine gel enema-treated patients and 69% of patients treated with mesalazine foam enema (P = 0.608). Endoscopic remission rates at week 4 were 51 and 52% for the mesalazine gel and foam enemas, respectively (P = 0.925). Histological remission was achieved by 30% of patients in both groups. Patients reported that the new mesalazine gel preparation was significantly better tolerated than the foam enema. Patients in the foam group had significantly more difficulty in retention (25% vs. 6%, P < 0.05), abdominal bloating (50% vs. 26%, P < 0.005) and discomfort during administration (48% vs. 26%, P < 0.05).

CONCLUSION

The new mesalazine gel enema is efficacious and significantly better tolerated than the mesalazine foam enema.

Recognition of bactericidal/permeability-increasing protein by perinuclear anti-neutrophil cytoplasmic antibody-positive sera from ulcerative colitis patients: prevalence and clinical significance

BACKGROUND

The aim of this study was to evaluate a) the role of bactericidal/permeability-increasing protein (BPI) as a possible antigen determining perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) reactivity in ulcerative colitis and b) the prevalence and clinical correlates of anti-BPI antibodies in patients with ulcerative colitis on the basis of their p-ANCA status.

METHODS

p-ANCA and anti-BPI antibodies were evaluated by means of indirect immunofluorescence and enzyme-linked immunosorbent assay methods in a group of 112 ulcerative colitis patients (including 42 patients subjected to proctocolectomy) well defined as far as their clinical features and p-ANCA status.

RESULTS

Anti-BPI antibodies were detected in 24% of non-operated patients and were significantly more frequent in p-ANCA-positive patients (32% versus 5% in p-ANCA-negative patients; P < 0.015). The prevalence of anti-BPI antibodies was similar in non-operated and operated patients and was high in men, in patients with an extensive and aggressive disease, and in patients developing pouchitis after surgery.

CONCLUSIONS

These data indicate that BPI is a neutrophil antigen frequently recognized by p-ANCA-positive ulcerative colitis sera. The presence of anti-BPI antibodies appears to identify further immunologic and clinical heterogeneity in ulcerative colitis.

High prevalence of hyperchomocysteinemia in patients with inflammatory bowel disease: a pathogenic link with thromboembolic complications?

BACKGROUND AND AIMS

Why patients with inflammatory bowel disease are at increased risk for thrombosis is unknown. Since they may have impaired absorption of vitamins that regulate the metabolism of homocysteine, we tested the hypothesis that they have hyperhomocysteinemia, an established risk factor for arterial and venous thrombosis.

METHODS

The concentrations of total homocysteine (tHcy), folate and cobalamin were measured in blood samples from 61 consecutive patients with inflammatory bowel disease and 183 age- and sex-matched healthy controls.

RESULTS

The mean (+/- S.D.) concentration of plasma tHcy was higher in patients (12.2 +/- 7.7 micromol/l) than in controls (10.5 +/- 4.6, p = 0.045). Eight patients (13%) had concentrations of tHcy higher than the 95th percentile of distribution among controls, as compared with 9 healthy controls (5%, p = 0.04). The prevalence of folate deficiency was higher in patients (15%) than in controls (5%, p = 0.02). Oral administration of folate, cobalamin and pyridoxine to 15 patients for 30 days decreased their mean tHcy levels from 20.3 +/- 9.9 to 9.5 +/- 3.4 (p <0.001).

CONCLUSIONS

In patients with inflammatory bowel disease there is an increased prevalence of hyperhomocysteinemia, which can be corrected by the administration of folate, cobalamin and pyridoxine. The high prevalence of hyperhomocysteinemia may account for the thrombotic risk of IBD patients; whether or not its correction will decrease the thrombotic risk should be tested in properly designed clinical trials.

Tyrosine phosphorylation and proteolysis. Pervanadate-induced, metalloprotease-dependent cleavage of the ErbB-4 receptor and amphiregulin

Enhancement of tyrosine phosphorylation in cells by the application of pervanadate, an extremely potent phosphotyrosine phosphatase inhibitor, provokes the rapid metalloprotease-dependent cleavage of ErbB-4, a transmembrane receptor tyrosine kinase. The pervanadate-induced proteolysis occurs in NIH 3T3 cells expressing transfected human ErbB-4 and in several cell lines that express endogenous ErbB-4. One product of this proteolytic event is a membrane-anchored molecule of approximately 80 kDa, which is heavily tyrosine phosphorylated and which possesses tyrosine kinase catalytic activity toward an exogenous substrate in vitro. This response to pervanadate is not dependent on protein kinase C activation, which has previously been demonstrated to also activate ErbB-4 cleavage. Hence, the pervanadate and 12-O-tetradecanoylphorbol-13-acetate-induced proteolytic cleavage of ErbB-4 seem to proceed by different mechanisms, although both require metalloprotease activity. Moreover, pervanadate activation of ErbB-4 cleavage, but not that of 12-O-tetradecanoylphorbol-13-acetate , is blocked by the oxygen radical scavenger pyrrolidine dithiocarbomate. A second phosphotyrosine phosphatase inhibitor, phenylarsine oxide, also stimulates a similar cleavage of ErbB-4 but, unlike pervanadate, is not sensitive to pyrrolidine dithiocarbomate. Last, pervanadate is shown to stimulate the proteolytic cell surface processing of a second and unrelated transmembrane molecule: the precursor for amphiregulin, an epidermal growth factor-related molecule. Amphiregulin cleavage by pervanadate occurred in the absence of a cytoplasmic domain and tyrosine phosphorylation of this substrate.

Long-term observation of the perinuclear anti-neutrophil cytoplasmic antibody status in ulcerative colitis patients

BACKGROUND

Perinuclear anti-neutrophil cytoplasmic antibodies (p-ANCA) have been regarded as a possible immunogenetic marker of ulcerative colitis. If this were true, the p-ANCA status of a given patient should be constant over time; however, little information is available on this issue.

METHODS

One hundred and forty-five sera collected from 40 ulcerative colitis patients during a mean follow-up period of 50.6 months were tested for p-ANCA reactivity by indirect immunofluorescence.

RESULTS

At base line 24 patients (60%) were p-ANCA-positive, with no relationship to gender distribution, age at diagnosis, disease activity, or extension. During follow-up, changes in p-ANCA status occurred in 10 patients (25%). P-ANCA positivity during follow-up was associated with more aggressive forms of disease, whereas p-ANCA negativity was associated with stable remission.

CONCLUSIONS

Changes in the p-ANCA status over time occur in some ulcerative colitis patients. P-ANCA behaviour is associated with different clinical patterns of disease.

High prevalence of Helicobacter pylori infection in patients with colonic adenomas and carcinomas

In some uncontrolled studies, a high prevalence of Helicobacter pylori infection unexpectedly has been found in patients with colorectal cancer. The purpose of the study was to investigate the prevalence of H. pylori infection in patients with colonic polyps or cancer. We reviewed 50 consecutive patients with either colonic adenomas or cancer who entered a preliminary case-control study. For each patient, 2 age- and gender-matched control subjects were selected (72 males; mean age, 63.1 years). A further 44 consecutive patients (30 with polyps and 14 with cancer) subsequently were enrolled. The H. pylori prevalence in patients with either polyps or cancer was compared with that in control subjects. Anti-H. pylori immunoglobulin G antibodies were assayed by an immunoenzymatic method. The prevalence of H. pylori antibodies was 49 (49%) of 100 in control subjects, 40 (71.4%) of 56 in patients with polyps (p < 0.006 vs. control subjects), and 21 (55%) of 38 in patients with cancer (not significant). Among patients with colorectal cancer, H. pylori prevalence was 9 (69.2%) of 13 for patients evaluated at the time of diagnosis and 12 (48%) of 25 for patients evaluated 1 to 9 years after surgery. We conclude that colonic neoplastic lesions, especially adenomas, are associated with an increased prevalence of H. pylori infection. The mechanisms underlying this association need to be elucidated.

Constitutive proteolysis of the ErbB-4 receptor tyrosine kinase by a unique, sequential mechanism

The heregulin receptor tyrosine kinase ErbB-4 is constitutively cleaved, in the presence or absence of ligand, by an exofacial proteolytic activity producing a membrane-anchored cytoplasmic domain fragment of 80 kD. Based on selective sensitivity to inhibitors, the proteolytic activity is identified as that of a metalloprotease. The 80-kD product is tyrosine phosphorylated and retains tyrosine kinase activity. Importantly, the levels of this fragment are controlled by proteasome function. When proteasome activity is inhibited for 6 h, the kinase-active 80-kD ErbB-4 fragment accumulates to a level equivalent to 60% of the initial amount of native ErbB-4 (approximately 10(6) receptors per cell). Hence, proteasome activity is essential to prevent the accumulation of a significant level of ligand-independent, active ErbB-4 tyrosine kinase generated by metalloprotease activity. Proteasome activity, however, does not act on the native ErbB-4 receptor before the metalloprotease-mediated cleavage, as no ErbB-4 fragments accumulate when metalloprotease activity is blocked. Although no ubiquitination of the native ErbB-4 is detected, the 80-kD fragment is polyubiquitinated. The data, therefore, describe a unique pathway for the processing of growth factor receptors, which involves the sequential function of an exofacial metalloprotease and the cytoplasmic proteasome.

Controlled trial of oral 5-aminosalicylic acid for the prevention of early relapse in Crohn's disease

BACKGROUND

Recent data indicate that 5-aminosalicylic acid (5-ASA) is most effective in preventing relapse of Crohn's disease in patients with a short duration of remission before enrollment.

AIM

To evaluate the efficacy of oral 5-ASA treatment, started immediately after achieving steroid-induced remission, in preventing clinical relapses of Crohn's disease.

METHODS

Patients with active Crohn's disease, achieving remission on steroids, were randomized to oral 5-ASA 3 g/day or placebo, while steroids were tapered over 6 weeks. The trial was terminated after interim analysis showed a slightly higher relapse rate in the 5-ASA group, and the calculated probability of seeing a statistically significant difference by completing the study was minimal.

RESULTS

Final analysis included 117 patients (58 taking 5-ASA and 59 taking placebo; follow-up 9.2 +/- 6.5 months). Cumulative relapse rates at 6 and 12 months were 34% and 58% in 5-ASA patients and 31% and 52% in placebo patients, respectively (rate difference +0.095; 95% CI = -0.085 to +0.274). Subgroups analysis showed that 5-ASA was equally ineffective in patients with ileal, colonic or ileocolonic disease.

CONCLUSIONS

Contrary to previous results, in our study early introduction of treatment with oral 5-ASA did not prevent relapse in Crohn's disease patients treated with steroids to induce remission.

5-fluorouracil in combined trabeculectomy and clear-cornea phacoemulsification with posterior chamber intraocular lens implantation. A one-year randomized, controlled clinical trial

PURPOSE

To test the effect of postoperative subconjunctival 5-fluorouracil (5-FU) on the pressure outcome in combined procedure (limbus-based trabeculectomy + clear-cornea phacoemulsification).

METHODS

Prospective randomized, controlled clinical trial; n = 24 eyes (24 patients) with concurrent open-angle glaucoma and cataract; 12 eyes per treatment group; sample size adjusted for a minimal expected difference in the event rate between the 2 treatment groups = 50%, control rate = 20%; type I error = 0.05; power = 95%. Uncomplicated limbus-based trabeculectomy + uncomplicated clear-cornea phacoemulsification + posterior chamber intraocular lens. The 5-FU group = five subconjunctival injections of 5 mg 5-FU, starting from day 8 after surgery, one injection per week. Control group = no injections. The groups were matched for age, preoperative intraocular pressure (IOP), duration of preoperative antiglaucoma treatment, preoperative pilocarpine and adrenergics, preoperative laser trabeculoplasty, and beta-blockers in the fellow eye. The IOP less than or equal to 15 mmHg without treatment 1 year after surgery (IOP = average of the two highest values measured in the diurnal curve, 8 AM to 6 PM, one reading every 2 hours).

RESULTS

Each patient completed a 1-year follow-up. Ten of 12 eyes of the 5-FU group showed an IOP less than or equal to 15 mmHg at the end of follow-up versus 1 of 12 eyes in the control group (Fisher's exact test, P = 0.00064). The IOP range was 10 to 17 mmHg in the 5-FU group and 14 to 22 mmHg in the control group.

CONCLUSION

Postoperative 5-FU may improve the 1-year success rate of trabeculectomy combined with clear-cornea phacoemulsification.

Lack of effect of antineutrophil cytoplasmic antibodies associated with ulcerative colitis on superoxide anion production from neutrophils

BACKGROUND

Antineutrophil cytoplasmic antibodies (ANCAs) from patients with vasculitidis can induce neutrophils to release oxygen radicals in vitro. ANCAs with a perinuclear pattern of immunofluorescence are found in most patients with ulcerative colitis, but several findings are against ANCAs having a pathogenetic role in this disease.

AIMS

To evaluate the influence of ANCAs associated with ulcerative colitis on the respiratory burst activity of neutrophils.

PATIENTS

Serum samples were obtained from 14 patients with ulcerative colitis, seven of whom showed positivity for p-ANCAs, three patients with vasculitidis, two with positivity for p-ANCAs, and one for c-ANCAs, and seven healthy volunteers.

METHODS

A positive ANCA serology was determined with a standard indirect immunofluorescence assay. Purified immunoglobulins (IgGs) were prepared from serum samples by DEAE-Affigel blue chromatography. Human neutrophils were prepared by dextran-Ficoll-Hypaque separation. Superoxide anion (O2-.) generation was measured by following the superoxide dismutase inhibitable reduction of ferricytochrome.

RESULTS

There were no significant differences among samples from ulcerative colitis IgG p-ANCA positive, ulcerative colitis IgG p-ANCA negative patients, and controls on O2-. production, whereas ANCA positive IgG from vasculitidis significantly enhanced O2-. release (p < 0.001).

CONCLUSIONS

p-ANCAs associated with ulcerative colitis have no effect on the respiratory burst activity of normal human neutrophils in vitro. These results reinforce the hypotheses that ANCAs are unlikely to contribute to the pathogenesis of ulcerative colitis.

Effect of a YAG laser iridotomy on intraocular pressure in pigment dispersion syndrome

PURPOSE

To determine whether an iridotomy can prevent an increase in intraocular pressure (IOP) in patients with pigment dispersion syndrome.

METHODS

Consecutive subjects (n = 21) recruited into this randomized, controlled clinical trial in a hospital-based outpatient referral center, had pigment dispersion syndrome in both eyes, and underwent a YAG laser iridotomy in one eye (randomly chosen); no intervention was performed in the fellow eye. A significant elevation of IOP was arbitrarily defined as an increase of more than 5 mmHg.

RESULTS

Eleven (52.3%) untreated eyes versus 1 (4.7%) treated eye showed a significant elevation of IOP during the 2-year follow-up. The IOP difference between the untreated and the fellow treated eye at the end of the 2-year follow-up period is inversely related to the age of each patient.

CONCLUSION

YAG laser iridotomy may reduce the incidence of ocular hypertension in eyes affected by pigment dispersion syndrome. This effect, being less pronounced after 40 years of age, may be of clinical relevance in young subjects.

Selective cleavage of the heregulin receptor ErbB-4 by protein kinase C activation

The 180-kDa transmembrane tyrosine kinase ErbB-4 is a receptor for the growth factor heregulin. 125I-Heregulin binding to NIH 3T3 cells overexpressing the ErbB-4 receptor is rapidly decreased by 12-O-tetradecanoylphorbol-13-acetate (TPA) pretreatment. Immunologic analysis demonstrates that TPA treatment of cells induces the proteolytic cleavage of ErbB-4, producing an 80-kDa cytoplasmic domain fragment, which contains a low level of phosphotyrosine, and a 120-kDa ectodomain fragment, which is released into the extracellular medium. Cleavage of ErbB-4 was also enhanced by other protein kinase C activators, i.e. platelet-derived growth factor, ionomycin, and synthetic diacylglycerol, while protein kinase C inhibition or down-regulation suppressed the TPA stimulation of ErbB-4 degradation. TPA did not induce the degradation of related receptors (ErbB-1, ErbB-2, and ErbB-3) in the EGF receptor family. The phorbol ester-induced cleavage of ErbB-4 occurs within or close to the ectodomain, as the 80-kDa cytoplasmic domain fragment is recognized by antibody to the ErbB-4 carboxyl terminus and is membrane-associated. Coprecipitation experiments show that, while the 80-kDa ErbB-4 fragment is associated with the SH2-containing molecules PLC-gamma1 and Shc, TPA did not induce the phosphorylation of these substrates in intact cells. In addition, kinase assays in vitro indicate that the 80-kDa fragment is not an active tyrosine kinase. These results show that protein kinase C negatively regulates heregulin signaling through the ErbB-4 receptor by the activation of a selective proteolytic mechanism.

Expression of acylphosphatase in Saccharomyces cerevisiae enhances ethanol fermentation rate

Previous experiments in vitro have demonstrated the ability of acylphosphatase to increase the rate of glucose fermentation in yeast. To evaluate the possibility of increasing fermentation in vivo also, a chemically synthesized DNA sequence coding for human muscle acylphosphatase was expressed at high level in Saccharomyces cerevisiae. Ethanol production was measured in these engineered strains in comparison with a control. Acylphosphatase expression strongly increased the rate of ethanol production both in aerobic and anaerobic culture. This finding may be potentially important for the development of more efficient industrial fermentation processes.

The Topcon SP 1000 and Image-NET systems. A comparison of four methods for evaluating corneal endothelial cell density

The objective of this study was to compare four methods of counting corneal endothelial cell density using the Topcon SP 1000 microscope and Image-NET digital graphic software. Two independent observers quantified cell density from 63 endothelial photomicrographs using the various standardized techniques. The first method was that suggested for use with Topcon SP 1000, employing five different reference grids to compare subjectively with the endothelial cell density of the unknown sample. The other three methods involved the automated, semiautomated, and manual procedures developed for use with the Image-NET system software. The manual Image-NET system is presently considered to yield accurate cell morphology data. Confidence limits and standard errors of mean differences between values obtained by different methods were used to evaluate agreement and reproducibility of computerized methods. Sensitivity and specificity were calculated for two different threshold limits of endothelial cell density. Results showed that the automated Image-NET system is not reliable for clinical use because of its poor agreement with other methods and its lack of sensitivity and specificity at the selected threshold limits of endothelial cell density. The comparative Topcon method of using reference grids, although inexpensive and accurate for 500 cell/mm2 increments, was considered too imprecise for most clinical situations. The semiautomated Image-NET system, in half the analysis time required by the manual method, provided endothelial cell count estimates that were not clinically different from those obtained with manual counting.

Serial administration of adrenergic antagonist and agonist ("pulsatile therapy") reduces the incidence of long-term drift to timolol in humans

PURPOSE

To test whether the incidence of long-term drift to timolol can be reduced by a "pulsatile" treatment (6 months timolol-2 months dipivefrin).

METHODS

In a randomized clinical trial, 100 consecutive subjects with ocular hypertension or high-tension primary open-angle glaucoma in at least one eye were randomly assigned to either group A, which was administered timolol 0.5% twice a day (b.i.d.), or to group B, which was administered timolol 0.5% b.i.d. (6 months) alternated with 0.1% dipivefrin b.i.d. (2 months). Diurnal intraocular pressure (IOP) was measured at recruitment, 1 month later during timolol administration ("reference value"), and every 6 months in group A or at the end of each pulse in group B. In bilateral cases, the right eye only was considered for the analysis. Length of follow-up was 54 months. Long-term drift was diagnosed if the IOP on timolol increased by at least 5 mm Hg over the reference value and was followed by a </ = 2mm Hg increase after withdrawing timolol for 2 weeks.

RESULTS

Reference values were comparable in both groups (16.4+/-1.2 mm Hg in group A, 15.9+/-1.7 mm Hg in group B). Eleven subjects (four in group A and seven in group B) did not complete follow-up because IOP increased >5 mm Hg in the study eye without detectable drift to the beta-blocker. The actual 54-month incidence of long-term drift was 45% (21/46) in group A versus 7% (3/43) in group B (P<0.01). In group B, IOP was always higher during dipivefrin pulse than on timolol (paired samples t-test, P<0.01). However, dipivefrin proved more effective through follow-up; IOP was 21.1+/-1.2 mm Hg at month 8 (first "pulse") and 18.6+/-0.95 mm Hg at month 48 (last "pulse") (paired samples t-test, P<0.01).

CONCLUSIONS

Serial administration of adrenergic antagonist and agonist can reduce the incidence of long-term drift to the beta-blockade in ocular hypertension and primary open angle glaucoma.

Primary biliary cirrhosis is associated with specific changes in liver IgG-bearing cell subpopulations

BACKGROUND/AIMS

The density of total IgG-bearing cells and the distribution of their subclasses were studied in the liver of patients with primary biliary cirrhosis.

METHODS

Immunohistochemistry and computerized image analysis were used to compare liver specimens from 18 patients with primary biliary cirrhosis and 28 with chronic hepatitis of different etiology.

RESULTS

The density of total IgG-bearing cells was similar in the two groups. However, in patients with primary biliary cirrhosis the proportion of IgG3-positive cells was significantly higher than in patients with chronic hepatitis (53 +/- 7% vs. 7.5 +/- 2.4%) (p < 10(-8)). Conversely, IgG1-positive cells were significantly less prevalent in patients with primary biliary cirrhosis than in chronic hepatitis patients (27 +/- 6.9% vs. 68 +/- 7.2%, p < 10(-8)). Stratification of patients with primary biliary cirrhosis according to histology did not show any difference in the distribution of IgG subclasses associated with the progression of disease.

CONCLUSION

These data suggest a pathogenetic role of local IgG3-bearing cells in primary biliary cirrhosis.

Decrease of intraocular pressure after subconjunctival injection of mitomycin in human glaucoma

OBJECTIVE

To investigate the effects of a subconjunctival injection of mitomycin on the intraocular pressure in human eyes affected by glaucoma.

DESIGN

Consecutive case series, prospective study, intraocular pairwise comparison (paired samples Student's t test adopted).

SETTING

Hospital-based glaucoma clinic.

PATIENTS

Twelve consecutive patients with bilateral glaucoma and monolateral blindness, intraocular pressure greater than 30 mm Hg in the blind eye (mean of the two highest values of the diurnal curve, confirmed at 96-hour interval), and no previous bulbar surgery.

INTERVENTION

Subconjunctival injection of 0.5 mL of 0.2% mitomycin in the upper temporal quadrant, preceded and followed by treatment with topical indomethacin.

MAIN OUTCOME MEASURE

Analysis of the variance of the mean intraocular pressure before and after the injection of mitomycin in each eligible eye.

RESULTS

An intraocular pressure decrease was observed in each eligible eye the day after the treatment (mean [+/- SD] decrease, 7.15 +/- 1.46 mm Hg). The effect was still detectable at the end of the 60 days of follow-up (mean [+/- SD] decrease, 5.67 +/- 1.61 mm Hg). No change of intraocular pressure, in the meantime, was observed in the fellow eye.

CONCLUSIONS

Topically applied mitomycin induces a decrease of intraocular pressure in human glaucomatous eyes. Our data confirm previous results obtained in albino rabbits and support the hypothesis that mitomycin exerts a still unknown direct effect on aqueous humor dynamics in the eye.

Properties of N-terminus truncated and C-terminus mutated muscle acylphosphatases

Enzymatic activity and structure of N-terminus truncated and C-terminus substituted muscle acylphosphatase mutants were investigated by kinetic studies under different conditions and 1H NMR spectroscopy, respectively. The N-terminus truncated mutant lacked the first six residues (delta 6), whereas arginine 97 and tyrosine 98 were replaced by glutamine giving two C-terminus substituted mutants (R97Q and Y98Q, respectively). All acylphosphatase forms were obtained by modifications of a synthetic gene coding for the human muscle enzyme which was expressed in E. coli. The delta 6 deletion mutant elicited a reduced specific activity and a native-like structure. The kinetic and structural properties of R97Q and Y98Q mutants indicate a possible role of Arg-97 in the stabilisation of the active site correct conformation, most likely via back-bone and side chain interactions with Arg-23, the residue involved in phosphate binding by the enzyme. This study also suggests a possible involvement of Tyr-98 in the stabilisation of the acylphosphatase overall structure.

Electroclinical diagnosis of Angelman syndrome: a study of 7 cases

The authors describe 7 new cases of Angelman syndrome (AS: 3 males and 4 females) diagnosed on the basis of clinical features (dysmorphic facial features, severe mental retardation with absent speech, peculiar jerky movements, ataxic gait and paroxysms of inappropriate laughter) and neurophysiological findings. Failure to detect deletion of the long arm of chromosome 15 or the absence of epileptic seizure were not considered sufficient to exclude a diagnosis of AS. Feeding problems, developmental delay and early signs of ataxia, especially tremor on handling objects and unstable posture when seated, proved effective as clinical markers for early diagnosis of AS. The EEG patterns characteristic of AS were found within the first 2 years of life (under 18 months in the majority of cases). The authors conclude that AS should be included in differential diagnosis in a child aged under 12 months having cryptogenic psychomotor retardation with prevalent language compromise. Repeat EEG recordings are needed to check for the typical trace, and cytogenetic investigations are mandatory.