Assessment of endothelial function during the loading phase of infliximab in psoriasis: a potential predictor of its drug survival.

BACKGROUND: Tumor necrosis factor inhibitors decrease the risk of cardiovascular events in moderate to severe psoriasis, but the association between their effects on endothelial function and those on skin lesions has not been well studied. We investigated the association between infliximab effects on endothelial function during the loading phase and those on skin lesions in patients with psoriasis. METHODS: We evaluated endothelial function with reactive hyperemia-peripheral arterial tonometry index (RHI) in 15 patients with psoriasis before the first and third infusions of infliximab. Patients were stratified into two groups; those who maintained Psoriasis Area and Severity Index (PASI) 75 response for more than 6 months (defined as responders) and the others (defined as nonresponders). RESULTS: Six weeks after the initiation of infliximab (before the third infusion), PASI scores were significantly improved compared with baseline, while RHI values were not altered in the whole patient group. However, when the responders and the nonresponders were analyzed separately, RHI values tended to be decreased before the third infusion compared with baseline in the nonresponders, while being unchanged in the responders. Importantly, the difference in ∆RHI reached a statistical significance between the two groups, and the cutoff value (mean - 2 standard deviation of RHI values in the responders) identified the nonresponders with 67% of sensitivity and 100% of specificity. CONCLUSIONS: The decrease in RHI values before the third infusion may serve as a predictor for the long-term unfavorable effect of infliximab on psoriatic skin lesions.

Propranolol is more effective than pulsed dye laser and cryosurgery for infantile hemangiomas.

UNLABELLED: Propranolol hydrochloride is a nonselective ß-blocker that is used for the treatment of hypertension, arrhythmia, and angina pectoris. In Japan, it was recently approved for the treatment of childhood arrhythmia. It has been observed to produce drastic involution of infantile hemangiomas. The aim of this prospective study was to examine propranolol's superiority to classical therapy with pulsed dye laser and/or cryosurgery in treating proliferating infantile hemangiomas. Fifteen patients between the ages of 1 and 4 months with proliferating infantile hemangiomas received grinded propranolol tablets 2 mg/kg per day divided in three doses. Twelve patients with proliferating infantile hemangiomas receiving pulsed dye laser and/or cryosurgery were enrolled as controls. Baseline electrocardiogram, echocardiogram, and chest x-ray were performed. Monitoring of heart rate, blood pressure, and blood glucose was performed every 2 weeks. Efficacy was assessed by performing blinded volume measurements and taking photographs at every visit. Propranolol induced significantly earlier involution and redness reduction of infantile hemangiomas, compared to pulsed dye laser and cryosurgery. Adverse effects such as hypoglycemia, hypotension, or bradycardia did not occur. CONCLUSION: The dramatic response of infantile hemangiomas to propranolol and few side effects suggest that early treatment of infantile hemangiomas could result in decreased disfigurement. Propranolol should be considered as a first-line treatment of infantile hemangiomas.

Structural and functional characterization of rabbit and human L-gulonate 3-dehydrogenase.

L-Gulonate 3-dehydrogenase (GDH) catalyzes the NAD(+)-linked dehydrogenation of L-gulonate into dehydro-L-gulonate in the uronate cycle. In this study, we isolated the enzyme and its cDNA from rabbit liver, and found that the cDNA is identical to that for rabbit lens lambda-crystallin except for lacking a codon for Glu(309). The same cDNA species, but not the lambda-crystallin cDNA with the codon for Glu(309), was detected in the lens, which showed the highest GDH activity among rabbit tissues. In addition, recombinant human lambda-crystallin that lacks Glu(309) displays enzymatic properties similar to rabbit GDH. These data indicate that GDH is recruited as lambda-crystallin without gene duplication. An outstanding feature of GDH is modulation of its activity by low concentrations of P(i), which decreases the catalytic efficiency in a dose dependent manner. P(i) also protects the enzyme against both thermal and urea denaturation. Kinetic analysis suggests that P(i) binds to both the free enzyme and its NAD(H)-complex in the sequential ordered mechanism. Furthermore, we examined the roles of Asp(36), Ser(124), His(145), Glu(157 )and Asn(196) in the catalytic function of rabbit GDH by site-directed mutagenesis. The D36R mutation leads to a switch in favor of NADP(H) specificity, suggesting an important role of Asp(36) in the coenzyme specificity. The S124A mutation decreases the catalytic efficiency 500-fold, and the H145Q, N196Q and N195D mutations result in inactive enzyme forms, although the E157Q mutation produces no large kinetic alteration. Thus, Ser(124), His(145) and Asn(196) may be critical for the catalytic function of GDH.