A lock-in thermal imaging setup for dermatological applications.

BACKGROUND: Lock-in thermal imaging is a thermographic method that is widely used in the nondestructive testing of materials. The technique allows detecting under the sample surface, small variations of the thermophysical properties in a noninvasive and noncontact manner. Surprisingly, this method has, to our knowledge, never been used in dermatology although it is particularly suited. METHODS: We present in this article the first lock-in thermal imaging setup dedicated to dermatological applications. The apparatus uses a temperature-modulated airflow to periodically stimulate the skin surface. The infrared images recorded by a high sensitive camera are demodulated according to the digital lock-in principle to compute a phase and amplitude image. RESULTS: First results obtained on benign skin lesions are presented. The images allow to detect small variations of the tissue thermophysical properties like for example, perfusion variations. Lock-in thermal imaging has the ability to reject disturbing thermal signals coming from subcutaneous tissues. The localization of the lesions is more accurate due the suppression of the lateral heat spreading. CONCLUSION: Lock-in thermal imaging is a promising method for the detection of lesions exhibiting modified thermophysical properties compared to the surrounding healthy skin.

Pruritic acquired nevus of Ota.

Nevus of Ota is a unilateral, asymptomatic cutaneous and mucosal hyperpigmentation of the face that is congenital or may appear during childhood. We present a case of symptomatic acquired nevus of Ota in an adult, associated with intense pruritus, not described in the literature so far. A 32-year-old woman presented with brownish mottled macules which appeared on her face progressively over 8 days, following the distribution of the first and second divisions of the left trigeminal nerve and partially covering the iris and sclera of the left eye. She reported an intense pruritus in this area. We performed a biopsy on the left forehead, which confirmed the diagnosis of nevus of Ota. Specific stains and immunohistochemistry revealed increased numbers of mast cells. Ophthalmological tests showed acute acquired melanocytosis of the left iris and sclera. The origin of the nevus is still unclear. Several hypotheses suggest a reactivation of melanocytes during their migration from the neural crest. The pruritus reported in our patient may be explained by the increased quantity of mast cells observed in the lesion and/or neuronal stimulation of the ophthalmic and maxillary divisions of the fifth cranial nerve.

[Lentigo maligna: a special melanoma]. / Lentigo maligna: un mélanome particulier.

Lentigo maligna (LM) and lentigo maligna melanoma (LMM) account for about 10% of all melanomas. They have distinct clinical and histological features as well as specific epidemiology, natural history, evolution, and genetics. Epidemiology of these tumors progressively concerns younger patients. Diagnostic and preparation of surgical removal of LM and LMM can now be optimized by new technologies of imaging, like dermoscopy or in vivo confocal reflectance microscopy. Surgery is the treatment of choice, but alternative options can be considered, especially for the elderly for whom the needs for efficiency and acceptability should be met.

[Scleroedema adultorum Buschke in a diabetic subject: intravenous immunoglobulin therapy]. / Scléroedème de Buschke chez un diabétique: traitement par immunoglobulines intraveineuses.

BACKGROUND: Scleroedema adultorum Buschke (SB) is a rare disease involving scleroedema of the neck and shoulders. It can extend to the rest of the trunk and the limbs but characteristically spares the extremities. Three types of SB are distinguished: the first is acute and develops after an infectious disease, the second is of insidious evolution and is associated with monoclonal gammopathy, and the third is associated with type 2 diabetes. PATIENTS AND METHODS: We report the case of a type 2 diabetic patient presenting with progressive, oedematous timbering of the trunk associated with impaired mobility, dysphagia and restrictive respiratory syndrome. SB was diagnosed on the basis of clinical presentation and histology. Treatment was mandatory because of the adverse impact of the disease. A therapy that would not worsen the patient's comorbidities had to be chosen. Intravenous immunoglobulins were thus initiated with excellent response as of the first cycle regarding trunk mobility and dysphagia. Cutaneous rigidity improved steadily until the end of treatment (eight cycles). CONCLUSION: Therapeutic abstention is the rule in SB if it has no severe functional repercussions. Nevertheless, there is no clearly indicated treatment once therapy becomes necessary. Control of underlying diabetes usually does not improve the scleroedema and the metabolic syndrome contraindicates most of the treatments reported in the literature. In this article, we suggest a new treatment of SB in the diabetic patient.

[Follow-up of melanoma lesions]. / Surveillance des lésions mélanocytaires.

Due to the early diagnosis, melanomas can be diagnosed in early stages. Most melanomas tend not to show morphological criteria of malignancy in the very early stages. They rather resemble benign moles. For patients with hundreds of atypical lesions, follow-up examinations using digital dermoscopy are very helpful. This technique enables the physician to monitor lesions and to detect microscopic change. Lesions with microscopic change are thought to be high risk lesions and should be removed this will represent important savings for the health system because this will allow to make the diagnosis of melanoma in earlier stages and to save costs for unnecessary surgery. In this article we are going to review the technique.

Heterogeneity of HLA-G gene transcription and protein expression in malignant melanoma biopsies.

Nonclassical MHC class I HLA-G antigen expression is tissue specific and is thought to play a role in tolerance of the semiallogeneic fetus by the maternal immune system. Ectopic expression of HLA-G by tumor cells provides them with an additional mechanism of escape from immunosurveillance by host cytotoxic effector mechanisms. The aim of this study was to assess the expression of nonclassical HLA-G antigens in ex vivo human melanoma biopsies. HLA-G mRNA levels corresponding to both membrane-bound and soluble protein isoforms were analyzed in tumor specimens obtained from primary or metastatic melanomas of 23 patients. High levels of HLA-G transcription were detected in tumor specimens in 5 of 23 patients and found to be comparable in both lymph node and skin metastases. HLA-G mRNA transcript levels at tumor sites in 18 of these patients were compared with those in samples of their own healthy skin and were higher in the tumor tissue in 12 patients. Differential expression of mRNA transcripts corresponding to soluble and membrane-bound HLA-G was also observed in some tumor biopsies. HLA-G protein expression was detected in tumors that exhibited high levels of HLA-G transcription by immunofluorescence of frozen sections and Western blot analysis of both tumor and healthy skin biopsies, using anti-HLA-G-specific monoclonal antibodies. This work provides evidence that HLA-G gene transcription and protein expression can be up-regulated ex vivo in melanoma. Our finding that several of the tumors studied expressed high levels of HLA-G provides additional clues as to how a tumor can be selected in vivo to escape from cytotoxic antitumor responses, constituting a new parameter to be considered in the design of therapeutic approaches aimed at enhancing antitumor immune responses.

[Cancer and fecundity]. / Cancer et fécondité.

The overall increase in relative survival rates of adult and childhood cancer patients is related to improved chemotherapy and radiotherapy treatment protocols. However, this success is tempered by gonadotoxic effects and uterine damage. The reduced fertility and possible premature menopause can have a profound impact on patients self-esteem and quality of life. Consequently, preservation of fertility or treatments to protect the ovarian function, become a more relevant issue. Advances in assisted reproduction techniques have focused on the following: embryo cryopreservation which is restricted by time and constrains such as, sexual maturity and the presence of a stable partner. Cryopreservation of immature ovarian tissue, the most promising option, with restoration of natural fertility following auto-transplantation or maturation of oocytes in vitro in combination with assisted reproduction.

Longitudinal follow-up of cellular and humoral immunity induced by recombinant adenovirus-mediated gene therapy in cancer patients.

Replication-defective adenoviruses are arousing growing interest as both gene therapy and vaccine vectors. In a phase I clinical trial designed to evaluate the feasibility and tolerance of recombinant adenovirus (rAd)mediated gene transfer, we previously demonstrated that a single intratumoral injection of 10(9) PFU of rAd encoding the beta-galactosidase protein (Ad-beta-Gal) induced strong short-term (1-3 months) humoral, helper (Th1 type) and cytotoxic T cell responses specific for the transgene product in patients with advanced lung cancer. The purpose of the present study was to evaluate the persistence of long-lasting immunity to the transgene protein and in parallel, to assess patient immunocompetence revealed by responses to recall antigens (tetanus toxoid, purified protein derivative), viral pathogens (Epstein-Barr virus, influenza virus), and allogeneic antigens in mixed lymphocytic reactions. The beta-Gal-specific proliferative response declined rapidly in patients with progressive disease, as did responses to the other antigens. In contrast, a long-lasting proliferative response to beta-gal was maintained in an immunocompetent patient in complete remission 2 years after an injection of 108 PFU of Ad-beta-Gal. Anti-beta-Gal humoral (IgG and IgA) responses persisted notably, as did responses to TT and poliomyelytic antigens. While T cell effector cytotoxic responses specific for the viral peptides plummeted, the frequency of anti-beta-Gal CTL precursors remained particularly high, thus attesting to major immunization. Despite the impact of both advanced disease and chemotherapy on immunocompetence, we show the long-term persistence of immunity to the transgene protein vectorized by rAd.

Direct evidence to support the role of antigen-specific CD8(+) T cells in melanoma-associated vitiligo.

Vitiligo is a cutaneous pigmentary disorder characterized by the loss of melanocytes. An autoimmune mechanism is strongly suspected to be involved in this affection given that it is frequently associated with autoimmune hormonal disorders, and because antibodies directed against melanocytic antigens are found in the serum of patients with vitiligo. We examined the role of cellular immunity in melanoma-associated vitiligo by expanding infiltrating lymphocytes from fresh biopsy specimens of vitiligo patches in melanoma patients. The vitiligo-infiltrating lymphocytes were almost exclusively T lymphocytes, and most were CD8(+). Following in vitro expansion, vitiligo-infiltrating lymphocytes remained predominantly CD8(+) and expressed the cutaneous homing receptor CLA. Furthermore, vitiligo-infiltrating lymphocytes had a clonal or oligoclonal T cell receptor profile, possibly reflecting specific antigenic stimulation. Finally, vitiligo- infiltrating lymphocytes specifically recognized differentiation antigens shared by normal melanocytes and melanoma cells. This direct demonstration of CD8(+) T cell involvement in vitiligo suggests that, in melanoma patients, vitiligo may be a visible effect of a spontaneous antitumoral immune response.

Melanoma peptide MART-1(27-35) analogues with enhanced binding capacity to the human class I histocompatibility molecule HLA-A2 by introduction of a beta-amino acid residue: implications for recognition by tumor-infiltrating lymphocytes.

The design of heteroclytic antigens with high MHC binding capacity is of particular interest to overcome the weak immunogenicity of peptide epitopes derived from tissue antigens expressed by tumors. In the present study, double-substituted peptide analogues of the tumor-associated antigen MART-1(27-35) incorporating a substitution at a primary anchor residue and a beta-amino acid residue at different positions in the sequence were synthesized and evaluated for binding to the human histocompatibility class I molecule HLA-A2 and for recognition by tumor-infiltrating lymphocytes. Interestingly, by combining a Leu for Ala substitution at P2 (which alone is deleterious for antigenic activity) with a beta-amino acid substitution at a putative TCR contact residue, recognition by tumor-infiltrating lymphocytes was partially restored. The analogue [Leu(28),beta-HIle(30)]MART-1(27-35) displays both a higher affinity to HLA-A2 and a more prolonged complex stability compared to [Leu(28)]MART-1(27-35). Overall, these results suggest that double-substitution strategies and beta-amino acid replacements at putative TCR contact residues might prove useful for the design of epitope mimics with high MHC binding capacity.

In vitro maturation and fertilization of goat oocytes frozen at the germinal vesicle stage.

The ability of frozen immature goat oocytes to undergo in vitro maturation (IVM) and fertilization (IVF) was investigated. Fully grown germinal vesicle stage (GV-stage) goat oocytes were submitted to different variables of cryopreservation: 1) exposure to propanediol before maturation but without freezing to detect the level of damage attributable to propanediol alone, 2) removal of cumulus cells to mimic damage attributable to osmotic stress during cryoprotectant exposure or freezing procedure, and 3) rapid freezing with propanediol. Maturation and fertilization rates were 82.1, 71, 65.3 and 23.7% and 71.2, 40, 58.4 and 23.1% for control, exposed, denuded and frozen oocytes, respectively. These results indicate that freezing sticto sensu (i.e., cooling and warming phases) have detrimental effects on IVM of GV-stage oocytes, whereas the reduced IVF rates of post-thaw matured oocytes are imputable to a cryoprotectant effect.

In vivo and in vitro survival of goat embryos after freezing with ethylene glycol or glycerol.

The aim of the present study was to compare the survival rates of goat morulae and blastocysts after different freezing procedures. The viability of frozen-thawed embryos was assessed both in vivo and in vitro. Two cryoprotectants, ethylene glycol and glycerol, were used and three cryoprotectant removal procedures were compared: progressive dilution in 1.0, 0.5, 0.3 and 0 M of cryoprotectant in PBS; a similar progressive dilution with cryoprotectant in PBS plus 0.25 M of sucrose; or one-step transfer in PBS containing 0.25 M of sucrose. In vitro development of frozen-thawed blastocysts was always higher than that of frozen morulae irrespective of the cryoprotectant (52 129 = 40.3% vs 23 161 = 14.3% ; P< 0.001). In vivo, however, frozen-thawed morulae developed equally as well as blastocysts after an identical freezing-thawing protocol. Development both in vivo and in vitro showed ethylene glycol to be a better cryoprotectant than glycerol for goat embryos at both developmental stages (23 vs 0%, 45 vs 35% in vitro; 34.5 vs 21%, 35 vs 23% in vivo for morulae and blastocysts, respectively).

Development of vitrified matured cattle oocytes after thawing and culture in vitro.

Bovine oocytes were partly denuded either at the beginning (t0) or six hours (t6) after the beginning of maturation and vitrified by the open pulled straw method at the end of the maturation process. After warming and fertilisation, their development in vitro and in vivo was assessed. The rates of production of blastocysts achieved in vitro were 3.4 per cent for the t0 group and 0.9 per cent for the t6 group compared with 40.4 per cent for the control oocytes. After transfer at the blastocyst stage pregnancies have been established in the three groups. Some of these pregnancies originated from vitrified oocytes which were further vitrified at the blastocyst stage before being transferred into synchronised recipients.

[Gilbert disease and isotretinoin]. / Maladie de Gilbert et isotrétinoïne.

INTRODUCTION: Because of the potential hepatotoxicity of retinoids, prescription of isotretinoin is always very carefully made in healthy subjects, and prohibited in case of concomitant hepatopathy. Gilbert's syndrome consists of chronic, mild, unconjugated hyperbilirubinemia. In this syndrome, isotretinoin has been reported twice to be perfectly tolerated, and once even beneficial. We report here a new case of good tolerance and even improvement of a Gilbert's syndrome during isotretinoin therapy. CASE REPORT: A 17-year-old man with Gilbert's syndrome presented with a nodulocystic acne. Topical agents had been inefficient, and cyclines bad tolerated. Thus isotretinoin has been gradually introduced, with a regular monitoring of the liver function. We observed a steady decrease of the bilirubinemia during the course of isotretinoin, and then a reappearance of hyperbilirubinemia as soon as posology was diminished and particularly after completion of isotretinoin therapy. DISCUSSION: A review of the literature finds only very few cases of hepatic injuries caused by isotretinoin, contrary to etretinate. Safety of isotretinoin in Gilbert's syndrome was first observed in 1984, but its beneficial effects have only recently been described by Wang et al., and we report here a similar case. Pharmacological mechanisms remain hypothetic. However, considering the prevalence of Gilbert's syndrome and its usual first expression during postpubertal period, it seems to us interesting for therapeutic practice to know that isotretinoin is not less safe in these patients.

Cryopreservation of cattle oocytes: effects of meiotic stage, cycloheximide treatment, and vitrification procedure.

Different parameters likely to influence the survival of bovine oocytes after a vitrification procedure were evaluated: oocyte meiotic stage, cycloheximide treatment at the beginning or the end of maturation, and three vitrification procedures using conventional straws, open pulled straws (OPS), or microdrops. For each procedure a mixture of cryoprotectants (25% ethylene glycol and 25% glycerol) was used. After the oocytes were warmed and subjected to in vitro maturation and fertilization, the number that developed into blastocysts was determined. Results show that cryoprotectant exposure reduced embryo development and that cycloheximide treatment had no beneficial effect on oocytes vitrified in conventional straws. Among the three vitrification procedures, only the OPS method yielded blastocysts (approximately 3% of vitrified oocytes) irrespective of their initial meiotic stage. This result highlights the major influence of the cooling rate in an oocyte vitrification protocol.

Changes in protein synthesis pattern during in vitro maturation of goat oocytes.

The regulation of meiotic events of goat oocytes from prophase I to metaphase II was studied by inhibiting protein synthesis at different times of the transition and by analyzing the changes in the protein synthesis pattern during maturation. Protein synthesis was required for germinal vesicle breakdown (GVBD). Nevertheless, the concomitant event to the rupture of germinal vesicle, i.e., chromosome condensation, took place even in a cycloheximide-containing medium. The transition from metaphase I to metaphase II was also protein synthesis dependent as evidenced by experiments using this protein synthesis inhibitor. The inhibition was partly reversible, i.e., after removal of the drug, oocytes were able to progress until metaphase I but could not proceed beyond this stage. Changes in the protein synthesis pattern were studied by radiolabelling of oocytes with [35S]methionine. These changes were correlated with the nuclear status of the oocyte: At GVBD, a polypeptide of 25 kD disappeared, while one of 27 kD appeared. At the same time, a polypeptide of 33 kD appeared, whereas concomitantly one of 34 kD became barely detectable and finally disappeared as the maturation progressed. During maturation, the synthesis of a 67 kD polypeptide increased and became predominant at the end of the maturation process. The synthesis of actin decreased after 18 hr of culture from a very high to a low level of synthesis.

Differential osmotic behavior of mammalian oocytes before and after maturation: a quantitative analysis using goat oocytes as a model.

This study shows that immature and mature goat oocytes respond differently to hyperosmotic stress; when exposed to a 1.5 M propanediol solution, immature oocytes manifest a higher osmotic stress than do mature oocytes. This is the consequence of both higher water permeability (133.9 +/- 15.2 vs 82.4 +/- 4.4 x 10(-3) cm/min) and lower propanediol permeability (0.87 +/- 0.03 vs 1.20 +/- 0.03 x 10(-3) cm/min at 20 degrees C) in the immature than in the mature stage. The difference of osmotic behavior between these two types of oocytes is abolished following exposure to cytochalasin D, a drug known to modify the cellular microfilament network. This result suggests differences in actin organization between the two types of oocyte, probably at the cortical level. Calculated values of the intracellular concentration of propanediol as a function of time of exposure show that propanediol rapidly permeates both types of oocyte and that the kinetics of intracellular concentration are lowered by cytochalasin treatment.

Protein phosphorylation patterns during in vitro maturation of the goat oocyte.

Protein phosphorylation patterns were studied by radiolabelling goat cumulus oocyte complexes with [32P]orthophosphate for various periods of time. The radiolabelled denuded oocytes were assessed for nuclear status and were used individually for gel electrophoresis. This study demonstrated that specific changes in protein phosphorylations were programmed during goat oocyte maturation. One of the most prominent changes was a general increase in the phosphorylation rate at germinal vesicle breakdown (GVBD). From 8 hr of culture, dominant phosphoprotein bands with apparent molecular weights of 27, 31, 40, and 50 kD were observed; they remained at this level until the metaphase II stage. In the molecular weight range of 65-80 kD, the protein phosphorylation pattern exhibited characteristic differences, with a complex series of phosphoproteins appearing and disappearing, duration maturation. Addition of 6-dimethylaminopurine (6-DMAP) at the onset of culture blocked the maturation process after GVBD and induced a dramatic condensation of chromatin. When added at different times after GVBD, 6-DMAP invariably induced chromosome condensation. This inhibition was partly reversible; i.e., after removal of the drug, oocytes were able to progress only until metaphase I.

Prolonged isolated fever due to attenuated extracerebral toxoplasmosis in patients infected with human immunodeficiency virus who are receiving trimethoprim-sulfamethoxazole as prophylaxis.

We report two cases of prolonged fever in deeply immunocompromised patients with AIDS who had been receiving trimethoprim-sulfamethoxazole (TMP-SMZ) as primary prophylaxis for several months. Investigations of the cause of fever yielded normal or negative findings except that the polymerase chain reaction (PCR) for Toxoplasma gondii in the blood was positive in both cases, and PCR of the bronchoalveolar lavage fluid was positive in one case. After a few days of treatment with pyrimethamine plus clindamycin, the two patients became afebrile and the T. gondii PCR became negative. The patients probably had disseminated toxoplasmosis attenuated by TMP-SMZ. PCR examination of blood for evidence of T. gondii genome may be useful in screening for causes of unexplained fever in patients with AIDS, even those who receive prophylaxis with TMP-SMZ.