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Biomedical subjects

A Reiner

Publications and source records attributed to A Reiner.

At least 55 records · Page 3Linked to original sources
PubMed2000

Do birds possess homologues of mammalian primary visual, somatosensory and motor cortices?

Recent data on the expression of several homeobox genes in the embryonic telencephalon of mammals, birds and reptiles support the homology of a part of the avian pallium, named the Wulst, and at least the more-medial and superior parts of mammalian neocortex. This conclusion is also supported by previous embryological, topological and hodological data. Furthermore, new evidence on the connections and electrophysiological properties of specific subfields within the avian Wulst, and on the thalamic territories that project to these fields, supports the more-specific conclusion that a primary visual area and a primary somatosensory-somatomotor area are present in the avian Wulst; these areas are likely to be homologous to their counterparts in mammals. In spite of this, developmental, morphological and comparative evidence indicate that some structural and physiological traits that appear to be similar in the Wulst and neocortex (such as the lamination or binocularity) evolved independently in birds and mammals.

Animals↗
PubMed2000

Nitrergic neurons make synapses on dual-input dendritic spines of neurons in the cerebral cortex and the striatum of the rat: implication for a postsynaptic action of nitric oxide.

Pre-embedding electron microscopic immunocytochemistry was used to examine the ultrastructure of neurons containing nitric oxide synthase and to evaluate their synaptic relationships with target neurons in the striatum and sensorimotor cerebral cortex. Intense nitric oxide synthase immunoreactivity was found by light and electron microscopy in a type of aspiny neuron scattered in these two regions. The intensity of the labeling was uniform in the soma, dendrites and axon terminals of these neurons. In both forebrain regions, nitric oxide synthase-immunoreactive neurons received synaptic contacts from unlabeled terminals, which were mostly apposed to small-caliber dendrites. The unlabeled symmetric contacts were generally about four times as abundant as the unlabeled asymmetric contacts on the nitric oxide synthase-immunoreactive neurons. Terminals labeled for nitric oxide synthase were filled with synaptic vesicles and were observed to contact unlabeled neurons. Only 54% (in the cerebral cortex) and 44.3% (in the striatum) of the nitric oxide synthase-immunoreactive terminals making apposition with the target structures were observed to form synaptic membrane specializations within the plane of the randomly sampled sections. The most common targets of nitric oxide synthase-immunoreactive terminals were thin dendritic shafts (54% of the immunoreactive terminals in the cortex and 75.7% of the immunoreactive terminals in the striatum), while dendritic spines were a common secondary target (42% of the immunoreactive terminals in the cortex and 20.6% of the immunoreactive terminals in the striatum). The spines contacted by nitric oxide synthase-immunoreactive terminals typically also received an asymmetric synaptic contact from an unlabeled axon terminal. These findings suggest that: (i) nitric oxide synthase-immunoreactive neurons in the cortex and striatum preponderantly receive inhibitory input; (ii) nitric oxide synthase-containing terminals commonly make synaptic contact with target structures in the cortex and striatum; (iii) spines targeted by nitric oxide synthase-containing terminals in the cortex and striatum commonly receive an asymmetric contact as well, which may provide a basis for a synaptic interaction of nitric oxide with excitatory input to individual spines.

Animals↗
PubMed2000

Localization of dopamine D1A and D1B receptor mRNAs in the forebrain and midbrain of the domestic chick.

The distribution and cellular localization of dopamine D1A and D1B receptor mRNAs in the forebrain and midbrain of the domestic chick were examined using in situ hybridization histochemistry with 35[S]-dATP labeled oligonucleotide probes, visualized with film and emulsion autoradiography. Labeling for D1A receptor mRNA was intense in the medial and lateral striatum, and moderately abundant in the pallial regions termed the archistriatum and the neostriatum, in the hypothalamic paraventricular nucleus region, and in the superficial gray layer of optic tectum of the midbrain. D1B receptor mRNA was abundant in the medial and lateral striatum, and in the pallial region termed the hyperstriatum ventrale, and moderately abundant in the intralaminar dorsal and posterior thalamus and in the superficial gray of the optic tectum. At the cellular level, about 75% of neurons in the medial striatum and 59% of neurons in the lateral striatum were labeled for D1A receptor mRNA, whereas about 39% of the neurons in the medial striatum and 21% in the lateral striatum were labeled for D1B receptor mRNA. Large striatal neurons were not labeled for D1A or D1B receptor mRNA. The data suggest that while both D1A and D1B receptors mediate dopaminergic responses in many neurons of the avian striatum, primarily D1A receptors mediate dopaminergic responses in the archistriatum and the neostriatum, while primarily D1B receptors mediate dopaminergic responses in the hyperstriatum ventrale and the thalamus.

Animals↗
PubMed2000

Causes of inconsistency in diagnosing and classifying intraductal proliferations of the breast. European Commission Working Group on Breast Screening Pathology.

It is now widely recognised that classifying ductal carcinoma in situ (DCIS) of the breast and diagnosing atypical ductal hyperplasia are associated with significant interobserver variation. Two possible reasons for this inconsistency are differences in the interpretation of specified histological features and field selection where morphology is heterogeneous. In order to investigate the relative contribution of these two factors to inconsistent interpretation of intraductal proliferations, histological sections of 32 lesions were sent to 23 European pathologists followed 3 years later by images of small parts of these sections. Kappa statistics for diagnosing hyperplasia of usual type, atypical ductal hyperplasia and ductal carcinoma in situ were 0.54, 0.35 and 0.78 for sections and 0.47, 0.29 and 0.78 for images, respectively, showing that most of the inconsistency is due to differences in morphological interpretation. Improvements can thus be expected only if diagnostic criteria or methodology are changed. In contrast, kappa for classifying DCIS by growth pattern was very low at 0.23 for sections and better at 0.47 for images, reflecting the widely recognised variation in the growth pattern of DCIS. Higher kappa statistics were obtained when any mention of an individual growth pattern was included in that category, thus allowing multiple categories per case; but kappa was still higher for images than sections. Classifying DCIS by nuclear grade gave kappa values of 0.36 for sections and 0.49 for images, indicating that intralesional heterogeneity has hitherto been underestimated as a cause of inconsistency in classifying DCIS by this method. More rigorous assessment of the proportions of the different nuclear grades present could lead to an improvement in consistency.

Breast↗
PubMed2000

Stress fractures in the Israeli defense forces from 1995 to 1996.

This study, encompassing 2591 Israeli soldiers, characterized Israeli soldiers with stress fractures to profile individuals who are prone to experience stress fractures: 318 with clinically and scintigraphically proven high grade stress fractures; 237 soldiers with symptoms but with normal scintigraphy; and 2036 soldiers with no symptoms. Soldiers with high grade stress fractures weighed less (68.4 +/- 7.9 kg versus 70.5 +/- 12.4 kg), smoked less, and reported fewer previous stress fractures, had fewer reports of stress fractures in their family histories, and had fewer incidences of bone diseases than did control subjects. Serum levels of bone specific alkaline phosphatase and osteocalcin were elevated in patients with high grade stress fractures compared with control subjects with no symptoms: 37.6 versus 26.2 units/L, and 10.8 versus 8.8 ng/mL, respectively. Levels of 25-hydroxy vitamin D were lower in patients with high grade stress fractures (25.3 ng/mL) than in control subjects (29.8 ng/mL). This study revealed that several parameters can distinguish soldiers with high grade stress fractures, but their predictive value and precise pathogenetic role remain unclear.

Adult↗
PubMed2000

Detecting gene copy number fluctuations in tumor cells by microarray analysis of genomic representations.

In this work, we explore the use of representations in conjunction with DNA microarray technology to measure gene copy number changes in cancer. We demonstrate that arrays of DNA probes derived from low-complexity representations can be used to detect amplifications, deletions, and polymorphic differences when hybridized to representations of genomic DNA. The method is both reproducible and verifiable, and is applicable even to microscopic amounts of primary tumors. We also present a mathematical model for array performance that is useful for designing and understanding DNA microarray hybridization protocols. The future applications and challenges of this approach are discussed.

Breast Neoplasms↗
PubMed2000

Succinic dehydrogenase histochemistry reveals the location of the putative primary visual and auditory areas within the dorsal ventricular ridge of Sphenodon punctatus.

In turtles, crocodilians, lizards and snakes, the dorsal ventricular ridge (DVR) is a nuclear cell mass that contains distinct visual and auditory thalamorecipient cell groups. In the tuatara (Sphenodon punctatus), the DVR is not organized into diverse cell groups but instead possesses a trilaminar cytoarchitecture resembling that characteristic of the telencephalic cortex in reptiles. To determine if visual and auditory fields might also be present in the DVR of Sphenodon punctatus, we used succinic dehydrogenase (SDH) histochemistry, which has been shown to delineate the visual and auditory fields of the DVR in turtles, crocodilians and lizards. We also used acetylcholinesterase (AChE) histochemistry to determine the boundary between the DVR and the basal ganglia in Sphenodon. We found an SDH-rich region in the neuropil ventral to the cell plate of the rostrolateral DVR and a slightly less intense SDH-rich zone in the neuropil deep to the cell plate of the ventromedial DVR. These SDH-rich zones appear to be located at the apical dendrites of the neurons of the adjacent cell plate. These SDH-rich zones were clearly located within the DVR and were distinct from the AChE-rich striatal part of the basal ganglia, which occupied the ventrolateral wall of the telencephalon. Based on findings in other reptiles, it seems likely that the SDH-rich zone in rostrolateral DVR represents the zone of termination of nucleus rotundus visual input to the DVR, whereas the zone in ventromedial DVR represents the zone of termination of nucleus reuniens auditory input. Because a trilaminar DVR such as that in Sphenodon might be the primitive DVR condition for reptiles, our results suggest that the cytoarchitecture of the DVR and the synaptic organization of its thalamic sensory input in the common ancestor of living reptiles might have been much like of the dorsal cortex.

Acetylcholinesterase↗
PubMed2000

[Breast cancer from the viewpoint of the pathologist].

Important criteria for histopathological evaluation in breast carcinoma are described. Of major importance is macroscopical evaluation. It is mainly the evaluation of the resection margins which still remains a clinically relevant problem for pathologists. New trends for intraductal carcinoma and evaluation of axillary lymph nodes are reported. An overview for prognostic factors is given.

Breast↗
PubMed1999

A simple and sensitive antigen retrieval method for free-floating and slide-mounted tissue sections.

The masking of antigens by aldehyde-containing fixatives or by paraffin embedding procedures is a problem for immunohistochemical studies. Enzymatic digestion, formic acid treatment, microwave heating and autoclave heating have been used to deal with this problem, with microwave heating-based antigen retrieval having become widely used as the method of choice. Microwave heating, however, has the shortcoming that it is difficult to precisely control the heating temperature and it is difficult to apply this method of heating to free-floating sections without damaging the sections. We describe here a simple, reliable and sensitive antigen retrieval method that uses water-bath heating. By this method, the temperature can be precisely controlled to yield effective antigen retrieval with minimal tissue damage in free-floating or paraffin-embedded slide-mounted sections. We found that the best results were obtained with a 30 min incubation in a 10-50 mM sodium citrate solution (pH 8.5-9.0) preheated to and maintained at 80 degrees C in a water-bath, followed by 30 min incubation in 0.3-3% nonfat dry milk to reduce nonspecfic staining. This method is highly effective for both 40 microm free floating sections, slide-mounted cryostat sections and paraffin-embedded slide-mounted sections, and it works well for tissue from diverse species (human, rat, mouse, pigeon, and zebra finch) and for diverse antigens (e.g. enkephalin, substance P, huntingtin, GluR1, GFAP, and ubiquitin). This method was also found to enhance immunolabeling in glutaraldehyde-fixed tissue that had been prepared for ultrastructural examination, without having a deleterious effect on the ultrastructure.

Animals↗
PubMed1999

Cellular localization of huntingtin in striatal and cortical neurons in rats: lack of correlation with neuronal vulnerability in Huntington's disease.

Immunohistochemistry and single-cell RT-PCR were used to characterize the localization of huntingtin and/or its mRNA in the major types of striatal neurons and in corticostriatal projection neurons in rats. Single-label immunohistochemical studies revealed that striatum contains scattered large neurons rich in huntingtin and more numerous medium-sized neurons moderate in huntingtin. Double-label immunohistochemical studies showed that the large huntingtin-rich striatal neurons include nearly all cholinergic interneurons and some parvalbuminergic interneurons. Somatostatinergic striatal interneurons, which are medium in size, rarely contained huntingtin. Calbindin immunolabeling showed that the vast majority of the medium-sized striatal neurons that contain huntingtin are projection neurons, but only approximately 65% of calbindin-labeled projection neurons (localized to the matrix compartment of striatum) were labeled for huntingtin. Calbindin-containing projection neurons of the matrix compartment and calbindin-negative projection neurons of the striatal patch compartment contained huntingtin with comparable frequency. Single-cell RT-PCR confirmed that striatal cholinergic interneurons contain huntingtin, but only approximately 65% of projection neurons contained detectable huntingtin message. The finding that huntingtin is not consistently found in striatal projection neurons [which die in Huntington's disease (HD)] but is abundant in striatal cholinergic interneurons (which survive in Huntington's disease) suggests that the mutation in huntingtin that causes HD may not directly kill neurons. In contrast to the heterogeneous expression of huntingtin in the different striatal neuron types, we found all corticostriatal neurons to be rich in huntingtin protein and mRNA. One possibility raised by our findings is that the HD mutation may render corticostriatal neurons destructive rather than render striatal neurons vulnerable.

Animals↗
PubMed1999

Influence of ophthalmic nerve fibers on choroidal blood flow and myopic eye growth in chicks.

Ophthalmic sensory nerve fibers containing substance P and calcitonin gene-related peptide' innervate the choroid in mammals and are known to vasodilate choroidal blood vessels. The avian choroid is also innervated by ophthalmic nerve fibers containing substance P and calcitonin gene-related peptide. The present studies were carried out to determine the influence of these sensory fibers on choroidal blood flow in birds and characterize their interaction with manipulations affecting eye growth. In these studies, ChBF was measured using laser Doppler flowmetry in both eyes in the following groups of birds: (1) normal chicks; (2) chicks with right optic nerve transected for 2 weeks; (3) chicks with right optic nerve transected and a goggle over the right eye for 2 weeks; and (4) chicks with right optic and ophthalmic nerves transected and a goggle over the right eye for 2 weeks. The eyes were refracted and various ocular dimensions measured after the blood-flow measurements. It was found that optic nerve transection reduced ChBF to 30% of normal. Placing a goggle (which increases ocular temperature by 4 degrees C) over an optic nerve transected eye nearly doubled choroidal blood flow over that in an optic nerve transected eye without a goggle. Additional transection of the ophthalmic nerve in a goggled optic nerve-transected eye, yielded choroidal blood flow that was indistinguishable from that in a nongoggled optic nerve-transected eye. Optic nerve transection had a slight stunting effect on axial growth of the eye. While myopic axial elongation was observed in goggled eyes with the optic nerve cut, the extent of myopia was less than in normal goggled eyes. Ophthalmic nerve transection further reduced the myopia induced by goggling in an optic nerve cut eye. These results suggest that ophthalmic nerve input to the choroid exerts a vasodilatory influence, which is activated in a goggled eye. This increased choroidal blood flow may be in response to elevated ocular temperatures caused by the goggling and this increase appears to be masked in goggled eyes with an intact optic nerve by the reduction in choroidal blood flow normally accompanying myopic eye growth. Our results thus show that the induction of myopic eye growth (as in our optic nerve cut eyes with a goggle) need not be accompanied by a decrease in choroidal blood flow from the baseline no-goggle condition (in this case, with the optic nerve cut).

Animals↗
PubMed1999

NMDA and non-NMDA receptor-mediated excitotoxicity are potentiated in cultured striatal neurons by prior chronic depolarization.

The excitatory input from cortex and/or thalamus to striatum appears to promote the maturation of glutamate receptors on striatal neurons, but the mechanisms by which it does so have been uncertain. To explore the possibility that the excitatory input to striatum might influence glutamate receptor maturation on striatal neurons, at least in part, by its depolarizing effect on striatal neurons, we examined the influence of chronic KCl depolarization on the development of glutamate receptor-mediated excitotoxic vulnerability and glutamate receptors in cultured striatal neurons. Dissociated striatal neurons from E17 rat embryos were cultured for 2 weeks in Barrett's medium containing either low (3 mM) or high (25 mM) KCl. The vulnerability of these neurons to NMDA receptor agonists (NMDA and quinolinic acid), non-NMDA receptor agonists (AMPA and KA), and a metabotropic glutamate receptor agonist (trans-ACPD) was examined by monitoring cell loss 24 h after a 1-h agonist exposure. We found that high-KCl rearing potentiated the cell loss observed with 500 microM NMDA or 250 microM KA and yielded cell loss with 250 microM AMPA that was not evident under low KCl rearing. In contrast, neither QA up to 5 mM nor trans-ACPD had a significant toxic effect in either KCl group. ELISA revealed that chronic high KCl doubled the abundance of NMDA NR2A/B, AMPA GluR2/3, and KA GluR5-7 receptor subunits on cultured striatal neurons and more than doubled AMPA GluR1 and GluR4 subunits, but had no effect on NMDA NR1 subunit levels. These receptor changes may contribute to the potentiation of NMDA and non-NMDA receptor-mediated excitotoxicity shown by these neurons following chronic high-KCl rearing. Our studies suggest that membrane depolarization produced by corticostriatal and/or thalamostriatal innervation may be required for maturation of glutamate receptors on striatal neurons, and such maturation may be important for expression of NMDA and non-NMDA receptor-mediated excitotoxicity by striatal neurons. Striatal cultures raised under chronically depolarized conditions may, thus, provide a more appropriate culture model to study the role of NMDA or non-NMDA receptor subtypes in excitotoxicity in striatum.

Animals↗
PubMed1999

CD44 expression in benign and malignant colorectal polyps.

PURPOSE: This retrospective study was undertaken to evaluate immunohistochemically the expression of CD44 standard protein and CD44v5 and CD44v6 isoforms in colorectal adenomas and early invasive cancers developing within adenomas as possible markers characterizing colorectal polyps with a more aggressive biologic potential. METHODS: Archival tissues of 81 consecutive locally resected colorectal polyps, comprising 57 colorectal adenomas and 24 carcinomas-in-adenomas, were stained immunohistochemically with the use of commercially available mouse monoclonal antibodies: SFF-2 for CD44 standard protein, VFF-8 for CD44v5, and VFF-7 for CD44v6. RESULTS: Sixty-three percent of the colorectal polyps were positive for CD44 standard protein, 59 percent were positive for CD44v5, and 27 percent were positive for CD44v6. Ninety-three percent of the low-grade adenomas were CD44 standard protein-positive, in contrast to 50 percent of the high-grade adenomas and only 42 percent of the carcinomas-in-adenomas (Kendall's Tau = -0.42; P < 0.0001). CD44v6 expression was more frequently found in early invasive cancers (54 percent) than in high-grade adenomas (25 percent) and low-grade adenomas (7 percent). This difference also was statistically significant (Kendall's Tau-b = 0.39; P = 0.00003). Surprisingly, a downregulation of CD44 standard protein expression was observed in the adenoma tissue adjacent to carcinomas (62 percent) and areas with high-grade atypia (71 percent), compared with low-grade adenomas (93 percent; Kendall's Tau-b = -0.28; P = 0.004). CONCLUSIONS: Our data suggest that CD44 standard protein and CD44 isoform v6 expression differs considerably in benign and malignant colorectal polyps. Clinical studies with larger patient groups could clarify the prognostic potential of CD44 further.

Adenoma↗
PubMed1999

Distribution of serum creatine kinase activity in young healthy persons.

The normal distribution of serum creatine kinase (CK) was determined in 428 men (mean age = 21.5) and 540 women (mean age = 20.2). The bootstrap method was employed to obtain statistical parameters of CK reference range and correlations with physical activity habits, BMI, cigarette smoking and alcohol consumption. CK distribution was non-Gaussian and skewed toward the higher values; 18.9% of the men and 4.6% of the women had values above the upper reference limits defined for the commercial assay kit. The median 97.5 percentile value was 532 u/l for men and 248 u/l for women (95% confidence interval of 384-738 u/l and 184-340 u/l, respectively). A significant correlation was found only between CK and alcohol consumption in men. Myoglobin level in a representative group of subjects correlated well with CK activity for both genders. Our findings define the range of CK values in a healthy, young, heterogeneous population. We suggest that only CK levels above the determined 97.5 percentile should warrant further clinical investigation.

Adult↗
PubMed1999

The distribution of dynorphinergic terminals in striatal target regions in comparison to the distribution of substance P-containing and enkephalinergic terminals in monkeys and humans.

Single- and double-label immunohistochemical techniques using several different highly specific antisera against dynorphin peptides were used to examine the distribution of dynorphinergic terminals in globus pallidus and substantia nigra in rhesus monkeys and humans in comparison to substance P-containing and enkephalinergic terminals in these same regions. Similar results were observed in monkey and human tissue. Dynorphinergic fibers were very abundant in the medial half of the internal pallidal segment, but scarce in the external pallidal segment and the lateral half of the internal pallidal segment. In substantia nigra, dynorphinergic fibers were present in both the pars compacta and reticulata. Labeling of adjacent sections for enkephalin or substance P showed that the dynorphinergic terminals overlapped those for substance P in the medial half of the internal pallidal segment, but showed only slight overlap with enkephalinergic terminals in the external pallidal segment. The substance P-containing fibers were moderately abundant along the borders of the external pallidal segment, and enkephalinergic fibers were moderately abundant in parts of the internal pallidal segment. Dynorphinergic and substance P-containing terminals overlapped extensively in the nigra, and both extensively overlapped enkephalinergic fibers in medial nigra. Immunofluorescence double-labeling studies revealed that dynorphin co-localized extensively with substance P in individual fibers and terminals in the medial half of the internal pallidal segment and in substantia nigra. Thus, as has been found in non-primates, dynorphin within the striatum and its projection systems appears to be extensively localized to substance P-containing striatopallidal and striatonigral projection neurons. Nonetheless, our results also raise the possibility that a population of substance P-containing neurons that projects to the internal pallidal segment and does not contain dynorphin is present in primate striatum. Our results also suggest the possible existence of populations of striatopallidal and striatonigral projection neurons in which substance P and enkephalin or dynorphin and enkephalin, or all three, are co-localized. Thus, striatal projection neurons in primates may not consist of merely two types, one containing substance P and dynorphin and the other enkephalin.

Animals↗
PubMed1999

Prognostic significance of mutations in the p53 gene, particularly in the zinc-binding domains, in lymph node- and steroid receptor positive breast cancer patients. Austrian Breast Cancer Study Group.

The aim of our study was to evaluate if p53 mutations, especially those in the L2/L3 domains of the p53 gene, add prognostic information for node-positive and steroid receptor positive breast cancer patients. Two hundred and five tumour samples from a randomised clinical trial of 596 lymph node- and steroid receptor positive breast cancer patients were included. All patients had been randomly allocated to receive 20 mg of adjuvant tamoxifen (TAM) daily for 2 years or TAM plus one cycle of low-dose, short-term chemotherapy. For detection of p53 mutations we used in vitro amplification by polymerase chain reaction and consecutively performed temperature gradient gel electrophoresis (PCR-TGGE) and direct sequencing. We found p53 mutations in 42/205 (20%) cases: 16/42 (38%) p53 mutations occurred within the L2/L3 domains of the p53 gene, and 26/42 (62%) outside the L2/L3 domains. p53 mutation served as a statistically significant parameter in predicting disease-free survival in univariate (P = 0.02) and multivariate (P = 0.009) analysis. For overall survival, no significant differences were observed. Patients with tumours that had p53 mutations within the L2/L3 domains of the gene showed no significant difference to those with mutations outside the L2/L3 domains for disease-free survival. For overall survival, mutations in the L2/L3 domains showed a marginally significant difference (P = 0.05) in multivariate analysis, but not in univariate analysis (P = 0.13). We conclude that mutation in the L2/L3 domains of the p53 gene is not an independent prognostic indicator of disease outcome for patients suffering from breast cancer with lymph node metastases and positive steroid receptors.

Adult↗
PubMed1999

Tretinoin-iontophoresis in atrophic acne scars.

BACKGROUND: Atrophic acne scars are a frequent problem after acne. Hitherto, mainly invasive treatment measures were possible. In a recent paper, we demonstrated the positive effects of iontophoresis with 0.025% tretinoin gel vs. estriol 0.03%. OBJECTIVE: In this further study, the recording of the clinical effects of iontophoresis with 0.025% tretinoin gel in atrophic acne scars was supplemented by immunohistochemistry investigations of collagen I and III, proliferation markers, and the estimation of epidermal thickness. METHODS: The treatment was performed twice weekly in 32 volunteer patients for a period of 3 months by application of the substance under a constant direct current of 3 mA for 20 min. Skin biopsies prior to and at the end of treatment were performed in 32 voluntary patients in order to investigate collagen I/III and proliferation markers by immunohistochemistry methods. RESULTS: Clinically, at the end of treatment, in 94% of patients a significant decrease in the scar depth was observed. Neither epidermal thickness nor proliferation markers revealed a significant increase at the end of treatment. Furthermore, collagen I and collagen III showed no common trend, as expressed statistically by a lack of significance. In some cases, increases in collagen III became evident at the end of treatment. CONCLUSIONS: Tretinoin-iontophoresis is an effective, noninvasive treatment of atrophic acne scars without causing disturbing side-effects.

Acne Vulgaris↗