Ashy Dermatosis in a Two-year-old Child: A Case Report and Mini-review.

Ashy dermatosis, or erythema dyschromicum perstans, is characterized by acquired grey patches distributed on the face, neck, trunk, and extremities with an unknown pathophysiology. Herein, we report a case of ashy dermatosis in a two-year-old child, possibly caused by an infection, with eventual improvement within two years, absent any treatment. To our knowledge, this is the second report of ashy dermatosis in a patient under the age of three years, and the first under the age of two years that was followed-up in the English-language literature from 2000 to 2021. Although the eruptions showed eventual improvement without any treatment in our case, all cases do not improve spontaneously. Further research is necessary to differentiate cases that eventually improve from resistant ones and determine treatment options for resistant cases.

Platelets are important for the development of immune tolerance: Possible involvement of TGF-ß in the mechanism.

Platelets have diverse roles in immune processes in addition to their key functions in haemostasis and thrombosis. Some studies imply that platelets may be possibly related to the immune tolerance induction. However, the role of platelets in the development of immune tolerance is not fully understood. The purpose of this study was to investigate the role of platelets in the development of regulatory mechanisms responsible for cutaneous inflammation using a mouse model of low zone tolerance (LZT). Mice were treated with 2,4,6-trinitro-1-chlorobenzene (TNCB) 8 times every other day for tolerance induction with administration of anti-platelet antibody or control antibody during the tolerance induction phase every 3 days. After the treatment for the tolerance induction, mice were sensitized and then challenged with TNCB. The contact hypersensitivity (CHS) was significantly decreased at 24 hours after challenge in the mice with LZT than in those without LZT. Platelet depletion via administration of anti-platelet antibody reversed the inhibition of CHS and reduced the frequency of Foxp3+ Tregs in the inflamed skin and draining lymph nodes in mice with LZT. In addition, repeated low-dose skin exposure resulted in elevated plasma levels of transforming growth factor (TGF)-ß1. Interestingly, platelet depletion reduced plasma TGF-ß1 levels of mice with LZT. Furthermore, the CHS response was reduced by administration of recombinant TGF-ß1 during platelet depletion in mice with LZT. Administration of anti-TGF-ß antibody reversed the inhibition of the CHS responses. These results suggest that platelets are involved in the induction of immune tolerance via the release of TGF-ß1.

A Prospective Trial Evaluating the Safety of a Shortened Infusion of Ramucirumab in Patients with Gastrointestinal Cancer.

LESSONS LEARNED: A shortened infusion of ramucirumab (from 60 to 20 minutes) was safe and feasible without infusion-related reactions.Twenty-minute infusions of ramucirumab can be an option for patients with no infusion-related reactions during the first 60-minute treatment. BACKGROUND: Ramucirumab is usually administered over 60 minutes, during which it is unlikely to cause infusion-related reactions (IRRs). This prospective study evaluated the safety of a shortened infusion of ramucirumab. METHODS: Patients who received their first dose of ramucirumab in a 60-minute infusion without developing IRRs were eligible and received their second ramucirumab dose for 20 minutes. The primary study endpoint was incidence of IRR during the first short-term infusion, and the secondary endpoints were incidence of IRR at any time and adverse events other than IRR. RESULTS: Of the 40 patients enrolled (median age, 68.5 years), 20 (55%) were male, 27 (67.5%) had stage IV gastric cancer, 25 (62.5%) received ramucirumab in combination with taxane-based chemotherapy, and 24 (60%) received only a single administration of ramucirumab prior to their enrollment. Notably, no IRR was observed during the first short-term infusion (IRR rate, 0%; 95% confidence interval [CI], 0%-0.72%). Among the 149 short-term infusions performed, there were no instances of IRRs or unexpected adverse events related to the treatment (Table 1). CONCLUSION: For patients without development of IRRs upon the first ramucirumab administration, shortening infusion time (from 60 to 20 minutes) is safe and feasible.

Verrucous lesions arising in lymphedema and diabetic neuropathy: Elephantiasis nostras verrucosa or verrucous skin lesions on the feet of patients with diabetic neuropathy?

Verrucous skin lesions on the feet in diabetic neuropathy (VSLDN) develop in areas with sensory loss in diabetic patients. Although various types of chronic stimulation, such as pressure or friction, are considered an important factor in the development of such lesions, the precise pathogenesis of VSLDN remains obscure, and there is currently no established treatment for this disease. Here, we present a case of VSLDN on the dorsum of the right foot. However, because lymphedema was also observed at the same site, this lesion could also be diagnosed as elephantiasis nostras verrucosa arising in diabetic neuropathy. The lesion was successfully treated with a combination of elastic stocking and mixed killed bacterial suspension and hydrocortisone ointment, which suggested that VSLDN might have been exacerbated by the pre-existing lymphedema. Because various types of chronic stimulation can trigger VSLDN, treatment plans should be devised on a case-by-case basis. Therefore, it is important to investigate the presence of factors that can induce or exacerbate chronic inflammatory stimulation, such as lymphedema in our case, in each patient with VSLDN.

Effect of buffer conditions on CYP2C8-mediated paclitaxel 6α-hydroxylation and CYP3A4-mediated triazolam α- and 4-hydroxylation by human liver microsomes.

1. Buffer conditions in in vitro metabolism studies using human liver microsomes (HLM) have been reported to affect the metabolic activities of several cytochrome P450 (CYP) isozymes in different ways, although there are no reports about the dependence of CYP2C8 activity on buffer conditions. 2. The present study investigated the effect of buffer components (phosphate or Tris-HCl) and their concentration (10-200 mM) on the CYP2C8 and CYP3A4 activities of HLM, using paclitaxel and triazolam, respectively, as marker substrates. 3. The Km (or S50) and Vmax values for both paclitaxel 6α-hydroxylation and triazolam α- and 4-hydroxylation, estimated by fitting analyses based on the Michaelis-Menten or Hill equation, greatly depended on the buffer components and their concentration. 4. The CLint values in phosphate buffer were 1.2-3.0-fold (paclitaxel) or 3.1-6.4-fold (triazolam) higher than in Tris-HCl buffer at 50-100 mM. These values also depended on the buffer concentration, with a maximum 2.3-fold difference observed between 50 and 100 mM which are both commonly used in drug metabolism studies. 5. These findings suggest the necessity for optimization of the buffer conditions in the quantitative evaluation of metabolic clearances, such as in vitro-in vivo extrapolation and also estimating the contribution of a particular enzyme in drug metabolism.

Contact sensitivity in patients with recalcitrant atopic dermatitis.

Patients with atopic dermatitis are usually responsive to conventional treatment such as topical steroids; however, they are sometimes refractory to the treatment. The influence of contact sensitivities on the course of patients with recalcitrant atopic dermatitis is not known. The aim of this study was to investigate whether contact sensitivities affect the course of patients with recalcitrant atopic dermatitis. We evaluated 45 patients with atopic dermatitis who had failed conventional therapy. Patch testing was performed with the Japanese standard series, metal series and/or suspected items. A total of 15 patients had a positive patch test reaction to at least one allergen. The most common allergens were nickel, topical drugs and rubber accelerators. Avoidance of products or food containing allergic substances greatly or partially improved skin symptoms in nine patients. These results suggest that contact allergens and metals may be critical factors causing eczematous lesions in patients with recalcitrant atopic dermatitis.

Clinical characteristics and prognostic factors in dogs with histiocytic sarcomas in Japan.

Canine histiocytic sarcoma (HS) is a rare neoplasm that originates from dendritic cells or macrophages, and there have been a number of cases experienced in Japan. To identify the characteristics and prognostic variables that determine outcome in dogs with HS in Japan, medical records of 73 dogs with HS were retrospectively analyzed. Signalment, clinical signs, complete blood count (CBC), blood chemistry profiles, treatment, response to treatment and overall survival (OS) were analyzed. Diagnosis of HS was determined histologically in 44 cases and cytologically in 29 cases. The most frequently diagnosed breeds were Flat-Coated Retrievers (n=16, odds ratio [OR] 62.0), Pembroke Welsh corgis (n=15, OR 9.7) and Bernese Mountain dogs (n=14, OR 45.0). Median survival time for all dogs in this study was 43 days. In the dogs that received no treatment or only symptomatic treatment, the median OS was 12 days (range 2-254 days) compared with that of dogs that received surgical treatment and/or chemotherapy (85 days, range 4-360 days). Univariate analysis identified anemia, thrombocytopenia, hypoalbuminemia, hypoproteinemia and not receiving antitumor treatment (chemotherapy and/or surgery) as factors significantly associated with shorter OS. Multivariate analysis confirmed that platelet counts, localized/disseminated lesional pattern and whether the dog received antitumor treatment were significantly predictive of survival.

Equilibrium vitrification of mouse embryos.

For the cryopreservation of embryos, vitrification has various advantages, but it also has disadvantages because embryos are vitrified with a considerable supercooling (i.e., in nonequilibrium). Here, we tried to develop a novel method in which embryos are vitrified in near-equilibrium. The extent of equilibrium was assessed by examining whether vitrified embryos survive after being kept at -80 degrees C. Two-cell embryos of ICR mice were vitrified with ethylene glycol (EG)-based solutions, either EFSa or EFSc solutions, which were mixtures of EG (30%-40%) and an FSa or FSc solution, respectively. The FSa and FSc solutions were PB1 medium containing 30% Ficoll plus 0.5 or 1.5 M sucrose, respectively. In vitro survival rate was high when embryos vitrified with 30%-40% EG (EFS30a, EFS40a, EFS30c, and EFS40c) were warmed rapidly. When embryos were vitrified and then kept at -80 degrees C for 4 days, large proportions survived with EFS30c and EFS40c. When embryos were vitrified with EFS35c or EFS40c, the survival rate was high even for those kept at -80 degrees C for 10 days. When embryos of ICR and C57BL/6J mice were vitrified with EFS35c or EFS40c and then kept at -80 degrees C for 4 days, the survival rate was high even after recooling in liquid nitrogen; a high proportion (75%) of C57BL/6J embryos vitrified with EFS35c developed to term after transfer. In conclusion, we have developed a novel method by which embryos are vitrified in near-equilibrium. This will be a supreme method for cryopreservation, retaining the advantages of both current vitrification and equilibrium slow freezing.

Diapolycopenedioic acid xylosyl esters A, B, and C, novel antioxidative glyco-C30-carotenoic acids produced by a new marine bacterium Rubritalea squalenifaciens.

Novel acyl glyco-carotenoic acids, diapolycopenedioic acid xylosyl esters A, B, and C, were isolated as red pigments by using chromatographic methods from a marine bacterium, Rubritalea squalenifaciens, belonging to subdivision 1 of Verrucomicrobia. The structures of these diapolycopenedioic acid xylosyl esters were determined to be 4-[2-O-acyl-beta-D-xylopyranosyl] hydrogen 4,4'-diapo-Psi,Psi-carotene-4,4'-dioate by spectroscopic analysis. Diapolycopenedioic acid xylosyl ester A showed potent antioxidative activity in a (1)O(2) suppression model.

The melanocortin receptor-1 gene but not the proopiomelanocortin gene is expressed in melanoblasts and contributes their differentiation in the mouse skin.

Alpha-melanocyte stimulating hormone (alpha-MSH) added to serum-free primary culture of melanoblasts derived from epidermal cell suspensions of 0.5 d old C57BL/10JHir mice induced their differentiation. Analysis using the reverse transcription-polymerase chain reaction showed that the expression of the melanocyte-specific alpha-MSH receptor gene, melanocortin receptor-1 (MC1-R), had already been initiated before addition of alpha-MSH, and, in addition, no up-regulation of the MC1-R gene was observed after addition of alpha-MSH. However, no expression of the proopiomelanocortin (POMC) gene was observed before or after the addition of alpha-MSH. The expression of the MC1-R and POMC genes in the epidermis and dermis of the dorsal skin was surveyed from 13 d old embryos to 5.5 d old neonates. The expression of the MC1-R gene was first observed in the epidermis of 13 d old embryos, and gradually increased up to 0.5 d after birth, and thereafter remained constant. By contrast, the expression of the MC1-R gene in the dermis was first observed in 16 d old embryos, and gradually increased up to 3.5 d after birth, and thereafter remained constant. However, no expression of the POMC gene was observed in the epidermis or dermis of the dorsal skin at any age of mice tested. These results suggest that the expression of the MC1-R gene, but not of the POMC gene, plays an important role in the regulation of melanocyte differentiation in mouse skin.

The melanocortin receptor subtypes in chicken have high preference to ACTH-derived peptides.

1 Melanocortin (MC) receptors are widely distributed throughout the body of chicken, like in mammals, and participate in a wide range of physiological functions. 2 To clarify the pharmacological impact of ligands acting in the MC system, we expressed the chicken MC1, MC2, MC3, MC4 and MC5 (cMC1-5) receptors in eukaryotic cells and performed comprehensive pharmacological characterization of the potency of endogenous and synthetic melanocortin peptides. 3 Remarkably, the cMC receptors displayed high affinity for ACTH-derived peptides and in general low affinity for alpha-MSH. It is evident that not only the cMC2 receptor but also the other cMC receptors interact with ACTH-derived peptide through an epitope beyond the sequence of alpha-MSH. 4 The synthetic ligand MTII was found to be a potent agonist whereas HS024 was a potent antagonist at the cMC4 receptor, indicating that these ligands are suitable for physiological studies in chicken. 5 We also show the presence of prohormone convertase 1 (PC1) and PC2 genes in chicken, and that these peptides are coexpressed with proopiomelanocortin (POMC) in various tissues.

Pheomelanin production in the epidermis from newborn agouti mice is induced by the expression of the agouti gene in the dermis.

The present study was designed to clarify the role of the agouti gene in the regulation of the proliferation and differentiation of mouse epidermal melanocytes using serum-free primary culture of epidermal melanocytes from 0.5-d-old black (a/a; C57BL/10JHir) mice and congenic, agouti (A/A; C57BL/10JHir-A/A) mice. There was no significant difference in the proliferation or differentiation of melanocytes between a/a and A/A mice. However, the content of pheomelanin in culture media from A/A melanocytes was increased by L-tyrosine compared with a/a melanocytes. In addition, the content of the pheomelanin precursor, 5-S-cysteinyldopa, in culture media from A/A melanocytes was dramatically increased by L-tyrosine. Moreover, pheomelanin content in the epidermis from 3.5- and 5.5-d-old A/A mice was much higher than in a/a mice. Analysis of the A gene using reverse transcription-polymerase chain reaction revealed that cultured keratinocytes and melanocytes do not express the A gene. Moreover, the A gene was expressed in the A/A dermis of 0.5-, 3.5- and 5.5-d-old mice, but not in the a/a dermis nor in the A/A or a/a epidermis. These results suggest that A/A epidermal melanoblasts are influenced by the A gene from the dermis of neonatal mice, and are capable of synthesizing pheomelanin in the culture. Pheomelanin production in the epidermis from 3.5- and 5.5-d-old A/A mice may be induced by the expression of the agouti gene in the dermis.