P. Cardo

The challenge of diagnosing atypical exanthems: A clinico-laboratory study

BACKGROUND Although atypical exanthems pose a severe diagnostic challenge, they have not been studied widely. OBJECTIVE To identify the clinical features, laboratory parameters and other characteristics that help establish the etiology of atypical exanthems. METHODS We collected the following information from 260 consecutive patients with atypical exanthems, including 108 children and 152 adults: demographic data, exanthem and enanthem morphology, clinical symptoms, month of outbreak and total duration. Throat, rectal, and vesicle swabs as well as urine and skin samples were examined for bacterial and viral signs. Serologic studies were performed for the most common infectious agents. RESULTS Seven morphological patterns were identified: macular erythema, papular erythema, macular-papular erythema, erythematovesicular, macular-papular erythema with petechiae, erythema with pustules, and urticarial. Ninety-four cases were due to viruses, 38 to bacteria, 65 to drugs, 3 to parasites, and one to viruses-plus-drugs. Nineteen of the 25 cases with a petechial pattern had an infectious etiology (12 viral and 7 bacterial) and only 4 were iatrogenic. Sixty-one of 69 patients with enanthems were infectious (57 viral and 4 bacterial), 6 were iatrogenic, and 2 remained undiagnosed. The petechial pattern was infectious in 80% of cases (14 viral and 2 bacterial). Four cases were iatrogenic. During the spring and summer, 60% of exanthems were infectious and 21% were iatrogenic. Picornavirus infections exhibited summer prevalence (57%), peaking in July. LIMITATIONS There were a variable number of patients with each of the morphological patterns. CONCLUSIONS Morphological patterns, seasonal occurrence, and enanthem are key for etiological diagnosis of atypical exanthems.

Reliability of hamilton-norwood classification.

Background: Hamilton-Norwood scale (HNS) has been largely used to assess clinically the severity of androgenetic alopecia (AGA), especially for therapeutical trials and even to establish its association with important diseases such as ischemic heart disease and prostate cancer. Objective To study HNS reproducibility in the hands of dermatologists and dermatology residents. Materials and Methods: Seven dermatologists and 16 residents in dermatology classified 43 photographs of male heads with different degrees of AGA. In a second study, 8 appraisers (3 dermatologists and 5 residents in dermatology) examined 56 pictures with the same procedure and repeated the observation 3 months later. In the first study, the inter-rater agreement was estimated by calculating an intra-class correlation coefficient (ICC). In the second study, for intra-rater repeatability, each raters scores from session 1 were paired with his/her scores for the same subjects in session 2, and the ordinary least products linear regression was calculated. Results: In the first study, the concordance of appraisers was unsatisfactory (ICC = 0.63-0.68)]. In the second study, repeatability was poor, without any significant difference between dermatologists and dermatology residents. Comment: Reliability of HNS is unsatisfactory even in the hands of expert appraisers. To obtain better reliability, the number of classes should be reduced, but with such reduction HNS would be usable to classify patients only in a broad way.

Potentially functional regions of nucleic acids recognized by a Kohonen's self-organizing map

Computer recognition of short functional sites on DNA, such as promoter regions or intron-exon boundaries, has recently attracted much interest. In this paper we have focused our attention on the automatic recognition of relevant features of human nucleic acid sequences by means of an unsupervised artificial neural network model. Sixty messenger RNA and 31 genomic DNA sequences were analysed. The results showed that in mRNA, the minimal similarity 60 base pattern was guanine- and cytosine-rich and located in most sequences in a range of 250 bases from either the middle point of the signal peptide coding region or from the start of the coding region. On DNA sequences a region defined by a cluster of minimal similarity patterns was present in many of the analysed genes. This zone may be related to alternative splicing and DNA methylation.

Studies on Rat Hair Cultures

SummaryBy means of two different quantification techniques the Authors were able to show that the addition of increasing concentrations of testosterone to the medium of hair-cultures simultaneously provokes an increased volume of epidermis as well as of hair-follicles and a better differentiation of hair follicles. The addition of dihydrotestosterone, on the contrary, does not induce any change.ZusammenfassungDurch die Verwendung von zwei quantitativen Methoden haben die Autoren gezeigt, daß Zusatz von steigenden Testosteronkonzentrationen an das Nährmedium von Haaren eine Hebung des Volumens von Epidermis und Haarfollikel und eine bessere Differenzierung der Haarfollikel gleichzeitig bewirkt.Dagegen bewirkt der Zusatz von steigenden Dihydrotestosteronkonzentrationen keine Veränderungen.SummaryThe authors have developed a technique to quantitatively assess follicle growth in culture. Rat hair follicles increase in volume when chondroitinsulfate A, but not B and C, is added to the culture medium.ZusammenfassungEs wurde eine Methode entwickelt, mit deren Hilfe das in vitro-Wachstum von Haarfollikeln quantitativ gemessen werden kann. Rattenhaarfollikel vergrößern das Organvolumen bei Zusatz von Chondroitinsulfat A, nicht aber B oder C zum Kulturmedium.

Polymorphous light eruption and benign summer light eruption in Italy

Background/purpose: Polymorphous light eruption (PLE) heterogeneity has been postulated, but the existence of benign summer light eruption (BSLE) is controversial. We studied the prevalence of the clinical patterns, criteria distinguishing BSLE from PLE, and diagnostic usefulness of phototest.

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.

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.

Proteomic-based screening of miRNAs metabolic pathway targeting

The analysis of miRNA expression profile is powerful support to screen new disease biomarkers. One miRNA can control the expression of several different protein mRNAs. Lack of knowledge about the process of target recognition is a weak point in the development of reliable computational tools for miRNA target selection. Here we present a novel integrative approach for to predict potential miRNA target. It is a workflow founded on integration proteomic and miRNA information. The software has been tested on a sample of proteomic data obtained from samples of mouse subjected to the effect of Environmental Cigarette Smoke (ECS).

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.