Daylight photodynamic therapy is an option for the treatment of actinic keratosis in patients with xeroderma pigmentosum in Africa

BACKGROUND

Xeroderma pigmentosum (XP) is a very rare and severe genetic disorder with a DNA repair defect of ultraviolet (UV)-induced damage. Photodynamic therapy (PDT) has been successfully used in XP patients to treat actinic keratosis (AK) and daylight PDT (DL-PDT) has demonstrated similar efficacy to conventional PDT (C-PDT) for AK.

OBJECTIVES

To assess DL-PDT for the treatment of AK in patients with XP.

METHODS

Patients with XP were evaluated by a group of Spanish and African dermatologists. Clinical characteristics of the patients were assessed and divided in mild, severe or moderate affectation of AK in the face. A topical photosensitizer was extended on the patients' faces and after two hours of indoor light exposure, fluorescence was assessed and the cream was removed. Patients were examined two and seven days later to assess the reaction to PDT and followed up three months later.

RESULTS

A total of 13 patients were treated on the whole face. Three were classified as severe AK, six as moderate AK and four as mild AK. Fluorescence assessment showed a soft yellow-green colour and a pink-color delineating the AK. Two days after treatment patients presented a scaly reaction. After one week the reaction healed, there was improvement and after three months no adverse events were noticed.

CONCLUSIONS

PDT is an option for treatment of AK in patients with XP.

Dermatofibrosarcoma protuberans with areas of giant cell fibroblastoma in the vulva: a case report

OBJECTIVE

To review the clinical, morphologic, immunohistochemical, and histogenetic characteristics of dermatofibrosarcoma protuberans with areas of giant cell fibroblastoma and explore current treatment options.

METHODS

We describe the case of a 38-year-old patient with a tumor measuring 5.7 cm on the right labium majus of the vulva. Serial sections stained with hematoxylin-eosin were examined and immunohistochemical staining was performed for CD34 and PDGF receptor alpha and beta (PDFGRA and PDGFRB).

RESULTS

The histologic study showed spindle-cell proliferation typical of dermatofibrosarcoma protuberans and other areas containing fibrosis and giant cells lining pseudovascular spaces. Both tumor areas expressed CD34, PDGFRA, and PDGFRB.

CONCLUSIONS

Only two cases of dermatofibrosarcoma protuberans with areas of giant cell fibroblastoma in the vulva have been reported to date. Both dermatofibrosarcoma protuberans and giant cell fibroblastoma are characterized by the translocation t (17;22) (q22;q13). The fact that PDGFRA and PDGFRB are overexpressed in these tumors opens new treatment options with imatinib. Surgical excision with wide margins or Mohs micrographic surgery continues to be the treatment of choice.

Comparison of intraocular treatment of DMTU and SOD following retinal ischemia in rats

The effect of intravitreal injections of DMTU (dimethylthiourea) and SOD (superoxide dismutase), two free radical scavengers, was evaluated in a rat model of retinal ischemia induced by elevated intraocular pressure. The drugs were administered just before or just after a 60 min ischemia. At days 2 and 7 after reperfusion, retinal recovery was evaluated by electroretinography. At day 7, layer thicknesses and cell rows were measured from histologic sections of paraffin-embedded retinas. In the vehicle-treated control group, we observed a decrease in the inner retinal layers and b-wave amplitude impairment. SOD injection (6 units/eye) protected the retina from ischemia/reperfusion injury. At day 2 after reperfusion, electroretinographic recovery was more efficient when SOD was administered just after ischemia (99%) than after pretreatment with SOD (81%) (p<0.03). In the DMTU-treated group (75 microg/eye), only the pretreatment induced significant electrophysiologic (40%) (p<0.001) and morphologic recovery.

Complex three-dimensional patterns of myosin isoform expression: differences between and within specific extraocular muscles

Because complex structural differences in adult extraocular muscles may have physiological and pathophysiological significance, the three-dimensional pattern of myosin heavy chain (MHC) isoform expression within the orbital and global layers of the muscle bellies compared with the distal tendon ends was quantitatively assessed. Three of the six extraocular muscles of adult rabbits were examined for immunohistologic expression of all fast, fast IIA/X, slow, neonatal and developmental MHC isoforms. The percentages of myofibers positive for each of these 5 myosin isoforms were determined in the orbital and global layers. There were relatively similar patterns of fast and slow MHC expression in the orbital and global layers of each of the three muscles examined. There were high levels of developmental MHC in the orbital layers, but significantly fewer developmental MHC positive myofibers in the global layer. The most variable expression was found with the neonatal MHC. There were significant differences between the longitudinal expression of the various isoforms in the middle of each muscle compared with the tendon end. In the orbital layer of all three muscles examined, the large numbers of fibers positive for fast MHC in the middle of the muscle dramatically decreased at the tendon end, with a concomitant increase in expression of slow myosin. There was a greater number of developmental MHC-positive myofibers at the tendon end than in the middle of the muscle in all three muscles examined. In the global layer, the IIA/X-positive myofibers comprised only half of the total number of fast-positive myofibers whereas in the orbital layer they comprised all or almost all of the fast positive myofibers. The configuration of the extraocular muscles is more complex than might be indicated by previous studies. The lateral rectus muscle had the most individual pattern of MHC expression when compared with the inferior rectus and inferior oblique muscles. Together with dramatic cross-sectional MHC fiber type differences between the orbital and global layers of the muscles, there are pronounced longitudinal differences in the proportions of myofibers expressing these five MHC isoforms in the middle region of the muscles and those in the distal tendon ends. This longitudinal progression appears to occur both within single myofibers, as well as within the series of myofibers that comprise the length of the muscle. We also confirm that the number of myofibers is reduced at the tendonous end while the cross-sectional area of each of the remaining myofibers is proportionally increased with regard to those in the muscle belly. Future studies may yet require two additional schemes for anatomic classification of the named extraocular muscles. One will be based on immunohistochemical features of their constituent myofibers as a supplement to classifications based on their electron microscopic appearance, innervation patterns or relative position with regard to the globe and orbit. Another will be based on the proportional length and longitudinal position of individual myofibers within an individual extraocular muscle.

Differential expression of activation epitopes of beta1 integrins in psoriasis and normal skin

In the epidermis, beta1 integrin expression is normally confined to the basal layer; however, suprabasal expression of beta1 integrins in keratinocytes has been found in psoriasis, and it has been suggested that it could be a pathogenic factor of the disease. We have investigated herein the functional state of beta1 integrins of human keratinocytes in normal skin and psoriasis. The expression of beta1-activation-reporter epitopes was monitored with two monoclonal antibodies, HUTS-21 and MG5A7, that recognize epitopes whose expression parallels functional activity of beta1 integrins and correlates with the ligand binding activity of these heterodimeric glycoproteins. We have found that keratinocytes express activation epitopes of beta1 integrins, and that these epitopes can be modulated by manganese. The expression of activation epitopes of beta1 integrins was related to an enhanced adhesion to fibronectin and collagen. Immunohistochemical studies of normal and psoriatic skin with HUTS-21 and other monoclonal antibodies indicate that, although there is suprabasal expression of beta1 integrins in psoriasis, these molecules seem to be in an inactive state. Moreover, most beta1 integrins in lateral and apical surfaces of basal keratinocytes of psoriasis are also in a nonactive conformation, implying a decrease of activity compared with normal skin, in which active beta1 integrins are distributed all over the basal keratinocytes.

Postprandial hypotension in Alzheimer's disease

The degree of postprandial hypotension in patients with Alzheimer's disease (AD) is not known. We therefore studied ten AD patients and 23 controls before and after a meal. Seven AD patients but only six controls showed a fall in blood pressure (BP) of 20 mmHg or more. Maximum BP fall in AD patients was observed between 20 and 120 min after food ingestion. This differed from the time course in other groups with primary chronic autonomic failure. Postural hypotension occurred in two controls, but not in AD patients. Abnormalities in cardiac vasomotor regulation, gut peptide liberation or both could be responsible for postprandial hypotension in AD.

Leishmaniasis presenting as a dermatomyositis-like eruption in AIDS

Three patients are described with leishmaniasis and AIDS, with cutaneous lesions mimicking dermatomyositis. Leishmania organisms were observed in great numbers in the dermis of lesional skin biopsy specimens. They were also present inside keratinocytes in all layers of the epidermis in one patient. Skin cultures from all patients and bone marrow culture in patients 1 and 3 revealed Leishmania infantum. Leishmania organisms were also found in nonlesional skin. The absence of proximal symmetric muscle weakness, elevated muscle enzymes, myopathic electromyograms, or characteristic histopathologic and immunologic features of dermatomyositis, and the rapid and complete clearance or marked improvement of the cutaneous lesions after treatment for leishmaniasis, make us consider true dermatomyositis unlikely. We suggest that leishmaniasis be included in the list of diseases capable of inducing a dermatomyositis-like eruption.

[Blood pool in the study of hepatic hemangioma]

Blood pool scintigraphy is a useful tool in the diagnosis of hepatic hemangioma. We reviewed retrospectively the clinical histories of 24 patients with abnormal blood pool scintigraphies and a presumptive diagnosis of hepatic hemangioma, based on clinical or ultrasonographic findings. In 20 of these patients, blood pool scintigraphy was diagnostic for hepatic hemangioma. The diagnosis was confirmed by an asymptomatic clinical evolution of 12 to 78 months in all the patients, CT scan in 8, angiography in 5 and liver biopsy in one. In the remaining 4 patients scintigraphy ruled out the presence of a hepatic hemangioma. Our results are similar to previous reports in the literature and blood pool scintigraphy has a high specificity for the diagnosis of hepatic hemangioma.

Local inhibition of inflammatory pain by naloxone and its N-methyl quaternary analogue

Inflammation was induced in rats by intraplantar administration of carrageenan (500 micrograms in 0.1 ml). Nociceptive thresholds were measured on both inflamed and contralateral hindpaws with the pressure test of Randal and Sellito. Low doses (0.03-10 micrograms/kg) of naloxone hydrochloride (Nx) or of methylnaloxone methylsulfonate (MeNx) were injected 4 h after carrageenan in the inflamed paw: Nx (3 micrograms) and MeNx (1-10 micrograms) diminished inflammatory pain; a slight, nonspecific hyperalgesia was observed in the contralateral paw after Nx, MeNx or NaCl. Neither drug was effective when injected s.c. at the same doses and time; however activities were shown to be influenced by the experimental schedule. Low s.c. doses of Nx antagonized the analgesia produced by s.c. morphine whereas MeNx did not. This work demonstrates the local site of the analgesic action of the doses of Nx and MeNx used here, bringing new evidence in favour of the existence of cutaneous opioid receptors. Opiate antagonists might inhibit inflammatory pain by interacting with a particular population of cutaneous receptors and (or) by being dealkylated locally into agonists.

Inhibition of inflammatory pain by naloxone and its N methyl quaternary analogue

Naloxone hydrochloride (Nx) and methylnaloxone methylsulfate (MeNx) antagonized the inflammatory pain, but not oedema, produced by intraplantar carrageenan in rats. The liminar effective dose (3 microgram/kg) was the same for the two drugs after intraplantar or subcutaneous injection. The s.c. dose effects curves were, as a whole, similar for the two drugs. The effect was long lasting and stereospecific. The low "analgesic" s.c. doses of Nx were able to antagonize morphine analgesia, those of MeNx were not. The interpretation is difficult; a peripheral action or better the local production of morphinomimetic metabolite(s) might account for most facts.

[Comparison of the effects of naloxone hydrochloride and methiodide on endotoxic shock in the anesthetized rat]

In the anesthetized rats, both naloxone hydrochloride and methiodide produced transient hypotension and bradycardia. The hydrochloride salt was able to revert (during 1 hr for the dose of 10 mg/kg I.V.) the hypotension produced by the endotoxin of Escherichia coli, the methiodide salt was ineffective. Further naloxone hydrochloride, produced tachycardia and some awaking of the animals which were not observed after the quaternary ammonium salt. These observations strengthen the view that the effects of naloxone observed in the shocked rat are of central origin and that the antihypotensive action results--partly at least--from the antagonism of beta endorphin released by the toxin.