Carla Cipriani

Flushing in rosacea: A possible mechanism

SummaryFlushing in rosacea has been investigated by means of (a) pharmacological inhibition of some possible chemical mediators and (b) titration of bradykinin as a possible effector directly in the blood. Clonidine-inhibited flushing was seen in all patients (mean 45%), other drugs had poorer results. Bradykinin increased in all patients at the climax of flushing (mean 60%). These findings support the hypothesis that epinephrine promotes a bradykinin release responsible for vasodilation.ZusammenfassungDie Flush-Reaktion bei Rosazea wurde (a) durch pharmakologische Hemmung einiger Mediatoren und (b) durch Titration von Bradykinin, das möglicherweise einen direkten Effektor im Blut darstellt, untersucht.Clonidin konnte die Flush-Reaktion bei allen Patienten (durchschnittlich um 45%) hemmen. Andere Medikamente zeigten schlechtere Ergebnisse. Der Bradykininspiegel fand sich auf dem Höhepunkt der Flush-Reaktion bei allen Patienten deutlich eleviert (durchschnittlich um 60%). Diese Ergebnisse belegen die Hypothese, daß Adrenalin die Freisetzung von Bradykinin fördert und somit eine Vasodilatation bewirken kann.

Production rate and composition of cerumen: Influence of sex and season

The production rate and composition of cerumen have been studied in 11 participants (5 men and 6 women), 25 to 42 years old. The cerumen was obtained in January, May, July, and November to investigate the possible influence of the season. Only the triglyceride content decreased from November to July. Sex was not a factor, which supported the hypothesis that sex hormones play a minor role in the production rate of the lipid component of cerumen.

Delayed Telogen Replacement in a Boy’s Scalp

Background: In case the shedding telogen hair is not replaced in time by a terminal anagen hair, an empty space results. Objective: To verify whether the phenomenon is present in prepubertal subjects. Methods: From July 1996 to May 1997, an 8-year-old boy was submitted monthly to the phototrichogram technique. Sixty hairs were monitored throughout the study. Results: 52% of all studied hairs were terminal anagen hairs throughout the study and additionally 22% were in a regular hair cycle. Vellus hairs and empty spaces were observed in 18 and 8% of follicles, respectively. In 2% of hairs, vellus hairs and empty spaces were associated. Conclusions: Vellus hairs and empty spaces are present even in children. Without gonadal androgens and expression or induction of 5α-reductase in the prepubertal scalp, they are unlikely to herald androgenetic alopecia (AGA) but could reflect a physiological phenomenon of ‘true resting’ of a small proportion of scalp hair. Androgens may increase the phenomenon which may account in part for AGA development.

Soluble and insoluble collagen and elastin in the rat hair cycle.

SummarySoluble and insoluble collagen and elastin were chemically evaluated in the dorsal skin of rats during the third hair cycle.Both fractions of collagen remain unchanged during anagen, while they increase considerably in the first days of telogen to drop afterwards.Elastin content gradually increases throughout anagen and falls in telogen.The authors suggest that the increasing amounts of collagen in the first part of telogen may be responsible for the progressive block in the downwards movements of previously growing follicles into the dermis.Elastin data could be the result of a mechanical readjustment of skin to the expansion provoked by growing follicles.ZusammenfassungDas lösliche und unlösliche Kollagen und das Elastin wurden chemisch auf der Rückenhaut der Ratten während des dritten Haarzyklus geschätzt. Beide Teile des Kollagens bleiben während des Anagens unverändert, während sie in den ersten Tagen des Telogens erheblich steigen und anschließend sofort fallen.Der Elastingehalt steigt graduell während des Anagens und fällt während des Telogens ab.Die Autoren sind der Meinung, daß die während der ersten Phase des Telogens eintretende Kollagenerhöhung für den Stop des Tiefenwachstums der Follikel verantwortlich sein kann. Die Veränderung des Elastins kann Folge einer mechanischen Auswirkung gegenüber den wachsenden Follikeln sein.

Adenyl-cyclase activity in rat-hair-cycle.

SummaryIn the skin of rat, during telogen phase, a high adenyl-cyclase activity coincides with maximal catecholamines content, minimal histamine level and blocking of mitoses in epithelial cells. These events suggest that in telogen the control of mitotic activity in rat hair follicles may operate through a block of G1 cells as already suggested for epidermal cells.ZusammenfassungWährend des Stadiums von Telogen fällt in der Haut der Ratte eine hohe Aktivität von “Adenyl-Cyclase” mit einer hohen Konzentration von “Katecholaminen”, einer geringen Konzentration von “Histamin” und eine Hemmung der Mitose von Epithelzellen zusammen.Diese Daten lassen die Annahme zu, daß während des Telogens die Kontrolle der Zellmitose in Haarfollikel durch eine Hemmung der G1-Phase vor sich geht. Ein entsprechender Mechanismus dürfte auch an epidermalen Zellen zu vermuten sein.

Metabolism of testosterone 4-14C in skin of castrated rats

SummaryTestosterone metabolism was studied in the skin and preputial glands of normal and prepuberally castrated male rats during the 2nd hair cycle. In catagen-telogen the 17-beta-OHSDH of dorsal skin was higher in castrated than in control animals; 5-alpha-reductase instead, remained unchanged through out the hair cycle.Also in the preputial glands of castrated rats 17-beta-OHSDH was higher than in normal rats. So was 5-alpha-reductase. A possible direct control of a substrate, like Testosterone, and/or of a hypophyseal tropin, like prolactin, on enzymes that direct the metabolism of steroids in target tissues is conceivable.ZusammenfassungDie Autoren studierten den Testosteron-Metabolismus der Haut und der Präputialdrüsen von normalen männlichen Ratten, die in der Vorpubertät während des zweiten Haarzyklus kastriert wurden.Im Katagen- und im Telogen-Stadium war die 17-beta-Hydroxysteroid-Dehydrogenase der Rückhaut in den kastrierten Ratten höher als in den normalen Ratten; dagegen blieb die 5-alpha-Reductase während des ganzen Haarzyklus unverändert.Auch in den Präputialdrüsen der kastrierten Ratten waren die 17-beta-Hydroxysteroid-Dehydrogenase und die 5-alpha-Reductase höher als in den normalen Ratten.Man darf annehmen, daß eine direkte Kontrolle eines Substrates — Testosteron und/oder eines pituitären Tropin als Prolactin — über Enzyme, die für den Metabolismus der Steroide im “Target”-Zielgewebe verantwortlich sind, denkbar ist.

A technique for measuring the rate of cerumen production

A technique is described for quantitatively measuring the rate of cerumen production. Two different washing solutions were tried. A mixture of alcohol/ether (3:1 v/v) appeared to be the best extracting solution yielding 2.05±0.22 versus 0.73±0.14 mg/week per ear obtained with Triton X‐100 solution. In addition, reproducibility was definitely better. Triton X‐100 may be useful whenever microbiologic evaluations are requested. Total lipids accounted for 73.3% of cerumen extracted with the former solution, triglycerides being 19.5%, and cholesterol 7.2%. Our extracting technique appears to be a good estimate of the cerumen global output and may supply important information about cerumen in several biologic conditions.

(+)-Catechin effects on X-rays irradiated skin of rats

SummaryThe effect of (+)-catechin on the skin of rats previously irradiated was a net decrease of AMPS content and a partial recovery of the insoluble collagen-loss due to X-Rays.ZusammenfassungBehandlung von vorbestrahlter Rattenhaut mit (+)-Catechin ergab eine Verminderung des sauren Mucopolysaccharidgehaltes sowie eine partielle Verbesserung des strahleninduzierten Abbaus von unlöslichem Collagen.