Biopharmaceutics: Effect of Ointment Bases on Topical and Transdermal Delivery of Salicylic Acid in Rats: Evaluation by Skin Microdialysis

Microdialysis has been used to determine the concentration of salicylic acid in skin tissue and plasma periodically for 4 h to evaluate the effect of ointment bases on topical and transdermal delivery of salicylic acid. The ointment bases examined were solbase (water-soluble), poloid and white petrolatum (oleaginous), hydrophilic poloid (water in oil (w/o) type emulsion lacking water) and absorptive ointment (w/o-type emulsion containing water). The ointments (0.1 g) containing 25 μmol salicylic acid were applied for 2 h to the surface of rat skin (1 cm²) with (intact) or without the stratum corneum. For intact skin, the extent of topical delivery from different ointments, evaluated by the area under the concentration-time curve (AUC) of salicylic acid in the skin tissue (AUCskin), increased in the order solbase. white petrolatum, poloid, hydrophilic poloid. absorptive ointment. The ratio of AUC_skin (topical delivery) to the AUC of salicylic acid in plasma (AUC_plasma, transdermal delivery) varied remarkably among the different bases, the greatest ratio being observed for absorptive ointment. When the ointments were applied to skin surface without stratum corneum, AUC_skin for solbase was much higher (about 45 times that for intact skin), whereas only a small (two-fold) increase was observed for poloid and hydrophilic poloid and the increase was negligible for white petrolatum and absorptive ointment. For skin without the stratum corneum, the ratio AUC_skin/AUC_plasma for the different ointments was comparable, although the magnitudes of AUC_skin and AUC_plasma still varied substantially. The variance of AUC values arises as a result of the different rates of release of salicylic acid from the bases. These results indicate that: the topical and transdermal delivery of salicylic acid in intact skin varies substantially among different ointment bases, and the greatest topical delivery is observed for absorptive ointment; use of absorptive ointment increases the retention of salicylic acid in the stratum corneum; and the stratum corneum functions strongly as a penetration barrier for solbase, moderately for poloid and hydrophilic poloid, and less for absorptive ointment and white petrolatum.     

Correlation between deletion patterns of SMN and NAIP genes and the clinical features of spinal muscular atrophy in Japanese patients

We conducted molecular analysis of two candidate genes for spinal muscular atrophy (SMA), the survival motor neuron gene (SMN) and the neuronal apoptosis inhibitory protein gene (NAIP), in 16 Japanese patients with SMA and compared the phenotypic features of SMA in these patients with the corresponding genotypes. Exons 7 and/or 8 of SMN were homozygously deleted in 11 SMA type I (Werdnig-Hoffmann disease) patients, two SMA type II patients and one SMA type III patient. Exons 5 and 6 of NAIP were homozygously deleted in six SMA type I patients. No patient had a deletion in NAIP without a deletion in SMN. Mechanical ventilation was required during the first 7 months of life in the SMA type I patients who had a deletion in both SMN and NAIP. Ventilatory support was initiated within 2 years after birth in patients who had a deletion in SMN but not in NAIP. We detected homozygous deletion of exon 5 of NAIP in the unaffected mothers of two SMA type I patients. In these families, the patients exhibited a deletion in both SMN and NAIP. The parents and unaffected siblings of these patients did not have a deletion in SMN. The present findings support the hypothesis that SMN deletion plays an important role in the development of SMA and suggest that combined deletion of both SMN and NAIP may be relevant for determining the disease severity.     

Epidemiology of sudden infant death syndrome in Japan

An epidemiological survey was carried out to examine the present situation with respect to sudden infant death syndrome (SIDS) in Kanagawa Prefecture. Questionnaires on sudden unexpected death of infants aged < 1 year in 1990-91 were sent to the hospitals and clinics in Kanagawa Prefecture which may take care of such infants. By analysing information from 10 485 replies, 48 out of 73 reported sudden infant deaths were confirmed to be SIDS, although autopsy was not performed in 13 cases (27%). The incidence of SIDS per 1000 live births in Kanagawa Prefecture was 0.29 in 1990 and 0.31 in 1991; and if limited to autopsy cases 0.19 and 0.25, respectively. Sudden infant death syndrome cases in Japan were found to occur more frequently when infants were < 6 months old, at home and sleeping alone, but less in the winter and between midnight and early morning. There was little difference between the numbers in prone and supine sleeping positions at discovery. It was not clear whether SIDS occurred more often to babies sleeping prone than supine, because there were no controls matched with the SIDS cases. In future, continuous epidemiological surveys of SIDS in Japan should be carried out.     

Influence of gum-chewing on the haemodynamics in female masseter muscle

Summary  Blood flow in active skeletal muscles provides energy substrate, oxygen and reduction of excessive heat and metabolic by-products. Although cyclic jaw motions such as those during mastication and speech articulation are the primitive oro-facial functions, possible effects of the cyclic muscle contractions on the intramuscular haemodynamics of the jaw muscles remains scarcely known. We investigated the masseteric haemodynamics during and after gum-chewing. Ten healthy female adults participated in the study. Electromyography, kinetics of masseter muscle oxygenation, electrocardiogram and blood pressure were recorded simultaneously. The subjects were asked to perform gum-chewing and cyclic jaw motion without gum bolus (empty-chewing task). The haemodynamics parameters were compared between the two experimental conditions. During gum-chewing task, deoxygenated haemoglobin and sympathetic nerve activity increased, while tissue blood oxygen saturation decreased. Blood pressure and parasympathetic nerve activity did not change. The overall behaviour of haemodynamic parameters during empty-chewing task was similar to that observed during gum-chewing task. However, the latency periods from the end of chewing until significant changes in the haemodynamic parameters were notably shorter ( P  < 0·05) in gum-chewing task as compared with those associated with empty-chewing task. The duration of the changes was shorter with empty-chewing than with gum-chewing. Fluctuations in masseter muscle haemodynamics associated with chewing jaw movement differed depending on the level of muscle contraction during movement. The differences became statistically significant immediately after the commencement of chewing and after the cessation movement. During the chewing movement, automatic nerve activities increased in response to the level of muscle contraction during movement.     

Assessment of Angiographic Coronary Calcification and Plaque Composition in Virtual Histology Intravascular Ultrasound

Objectives

We assessed the relation between coronary plaque composition and angiographic calcification by using virtual histology intravascular ultrasound (VH‐IVUS).

Background

The plaque vulnerability according to angiographic calcification is unclear.

Methods

Subjects were 140 consecutive patients (145 lesions) undergoing VH‐IVUS before percutaneous coronary intervention. Subjects were divided into 4 groups: no calcification group (n = 27), spotty group (n = 65) that had calcium deposits under 90° in grayscale IVUS, intermediate group (n = 37) had calcium deposits with 90° or more and under 180°, and extensive group (n = 16) had calcium deposits with 180° or more.

Results

The number of VH thin‐cap fibroatheromas in spotty group was significantly larger than no calcification group, intermediate group, and extensive group (0.66 ± 0.71 vs 0.22 ± 0.42 [P < 0.01], 0.32 ± 0.48 [P < 0.05], 0.13 ± 0.34 [P < 0.01], respectively). Spotty group without angiographic calcification had significantly larger %necrotic core than with angiographic calcification (24.5 ± 6.7% vs 19.9 ± 7.2%, P < 0.05). Intermediate group without angiographic calcification had significantly larger necrotic core area than with angiographic calcification (2.5 ± 0.9 mm² vs 1.7 ± 0.9 mm², P < 0.05). Extensive group with angiographic calcification had significantly larger %dense calcium than without angiographic calcification (18.3 ± 4.0% vs 13.4 ± 4.4%, P < 0.05).

Conclusions

Lesions with spotty calcification was highly vulnerable in VH‐IVUS. Spotty or intermediate plaque calcification without angiographic calcification was more vulnerable than those with angiographic calcification. Extensive plaque calcification with angiographic calcification had more dense calcium than those without angiographic calcification.

     

Immunohistochemical localization of lysyl oxidase in normal human skin

Lysyl oxidase (EC 1.4.3.13), a copper-dependent enzyme which catalyses the formation of aldehyde cross-links, and acts primarily on collagen and elastin, is known to be increased during wound healing and in fibrotic disorders including liver cirrhosis and atherosclerosis, and to be decreased in some hereditary connective tissue diseases and in malignant cell lines. A recent study showed that lysyl oxidase might possess tumour suppressor activity as an antioncogene for ras. Little is known about the localization of this enzyme in human skin. In this study, we determined immunohistochemically the localization of lysyl oxidase in normal skin of young and elderly subjects obtained from sun-exposed and unexposed regions of the body. All skin samples tested had similar distributions of lysyl oxidase. The enzyme was present both extracellularly and intracellularly. Extracellularly, a few granular aggregates of immunoreactants were observed along collagen and elastic fibres. These granules were more common in the adventitial portion of the dermis than in the reticular portion. Of all sun-exposed and unexposed regions studied, the skin of the face displayed the greatest amount of extracellular immunoreactants. Immunopositive granules were observed intracellularly in fibroblasts, vascular endothelial cells, sweat glands, sebaceous glands, arrector pili muscles and some keratinocytes. These findings provide evidence that, as suggested in recent reports, lysyl oxidase may have a variety of intracellular functions.     

Incidence of Kawasaki disease in Japan: the nationwide surveys of 1999–2002

BACKGROUND: The purpose of the present study was to describe the results of nationwide epidemiologic surveys of Kawasaki disease for the 4 year period 1999-2002. METHODS: The design is a retrospective incidence survey. The patients reported in these two surveys are all new patients who were reported during the two study periods (1999-2000 and 2001-2002), although the data were collected retrospectively. A questionnaire was sent to all pediatric departments of hospitals with 100 beds or more throughout Japan, requesting data on patients with Kawasaki disease, such as sex, age, date of first hospital visit, recurrence, and cardiac lesions. RESULTS: The total number of patients reported in the 4 year period 1999-2002 was 32 266 (18 604 male, 13 662 female), with an average annual incidence of 137.7 per 100 000 children younger than 5 years old. The male/female ratio was 1.30. The incidence peaked at 9-11 months of age, and the proportion of patients under 1 year of age was 26%. The monthly distribution had a high peak in January and a gradual increase in summer. Geographically, the high-incidence areas were limited to certain prefectures and moved from year to year. The cardiac lesions at acute stage and cardiac sequelae occurred more in children under 1 year and older than 4 years. Among the principal symptoms, fever persisting >or=5 days occurred most commonly, followed by conjunctival congestion, changes in lips and oral cavity, polymorphous exanthema, and changes of extremities. Cervical lymphadenopathy occurred less. CONCLUSION: More than 32 000 patients with Kawasaki disease during the 4 year period 1999-2002 were reported to the nationwide incidence surveys. The number of patients is steadily increasing despite the decrease of children. The seasonal variation, geographical distribution, and age-specific distribution support the infection theory for the etiology of Kawasaki disease.     

A Colonoscopic Study of Aphthoid Ulcers of the Large Intestine

Colonoscopic characteristics of aphthoid ulcers in amebiasis, Crohn's disease, and tuberculosis were evaluated. Multiple aphthoid ulcers were featured in 14 out of 15 cases of amebiasis, 7 out of 74 cases of Crohn's disease, and 5 out of 24 cases of tuberculosis. Aphthoid ulcers of amebiasis were often confined to the rectum and lower sigmoid colon, being characterized by marginal elevation and erythema. Crohn's aphthoid ulcers lacked the red halo in all but one case. No verrucous elevations were observed. The intervening mucosa appeared intact in all cases. Aphthoid ulcers of intestinal tuberculosis were oval or lozenge-shaped. They were surrounded by a marginal red halo in 4 cases (80%), however, the red halos found in tuberculosis patients were milder than those of patients with amebiasis. Aphthoid ulcers of Crohn's disease and tuberculosis showed a tendency to be arranged in a specific direction. Crohn's ulcers were arranged in a longitudinal fashion, whereas tuberculous ulcers were arranged in a circular fashion. Ulcers of amebiasis were arranged entirely at random. Biopsy from aphthoid ulcers of amebiasis showed parasites in 64%, whereas cytological studies were positive in 93% of cases.