Three-dimensional visualization of thoracodorsal artery perforators using photoacoustic imaging

Introduction: Diagnostic imaging modalities to evaluate the three-dimensional distribution of thoracodorsal artery perforators (TDAPs) are lacking. In this study, TDAPs were visualized and characterized using photoacoustic imaging. Material and methods: In this study, 34 sites in the lateral chest wall of 18 individuals were analyzed. The region extending 5 cm ventral and 5 cm dorsal to the lateral edge of the latissimus dorsi (LD) and 5–15 cm from the posterior axillary fold was scanned using photoacoustic imaging. The largest perforator closest to the edge of the LD was characterized. The location of the stem portion and the orientation of the longest cutaneous branch of the perforator were described. The relationship between the maximal depth of delineation on photoacoustic images and the depth of the deep fascia was assessed. Results: On average, 2.6 perforators (range, 1–5 perforators) were visualized in the region of interest. The distribution of the TDAP stem portion was similar to that in previous studies. Cutaneous branches were preferentially oriented in a medial-caudal direction. The length of delineated cutaneous branches varied (range, 7–78 mm) depending on the thickness of the subcutaneous layer. Vessels under the LD were observed when the subcutaneous layer was thin. Conclusion: Photoacoustic imaging can successfully visualize TDAPs in three dimensions. Visualization of TDAPs varied by the thickness of the subcutaneous layer. A thin deep fascia of the LD might be a cause of deep laser penetration

Squamous Cell Carcinoma of the Scalp after Artificial Hair Implantation

A 48-year-old man with a protruding tumor on the parietal region had undergone treatment of alopecia using artificial synthetic fibers 2 or 3 times a year for 10 years from 30 to 39 years old. Three months before the first consultation at our hospital, he noticed a small tumor that had gradually shown bleeding and discharge, with expansion of the affected area. A diagnosis of squamous cell carcinoma (SCC) was made based on a biopsy, and we resected the tumor with a 1-cm surgical margin from the reddened area around the protruding tumor (14 × 11 cm), including the periosteum membrane. No tight adhesion was found between the periosteum and skull, so we excised the outer table of the skull of the central part (diameter: 8 cm) for a pathological analysis. A pathological study showed moderately differentiated SCC with a negative surgical margin. The whole tumor was surrounded by scar tissue with buried artificial hair implants. The second surgery was performed on the 15th postoperative day. An anterolateral thigh flap was divided into 2 flaps to fit the circle-shaped wound. This is the second report of SCC developing after artificial hair implantation in the frontal-parietal scalp. The whole protruding tumor was surrounded by scar tissue with buried artificial hair implants. Proving the direct causal relationship between inflammation of scar tissue and SCC generation is difficult; however, our pathological findings support the possibility of the harmful effects of artificial hair implants

Novel Mouse Xenograft Models Reveal a Critical Role of CD4+ T Cells in the Proliferation of EBV-Infected T and NK Cells

Epstein-Barr virus (EBV), a ubiquitous B-lymphotropic herpesvirus, ectopically infects T or NK cells to cause severe diseases of unknown pathogenesis, including chronic active EBV infection (CAEBV) and EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH). We developed xenograft models of CAEBV and EBV-HLH by transplanting patients' PBMC to immunodeficient mice of the NOD/Shi-scid/IL-2Rγnull strain. In these models, EBV-infected T, NK, or B cells proliferated systemically and reproduced histological characteristics of the two diseases. Analysis of the TCR repertoire expression revealed that identical predominant EBV-infected T-cell clones proliferated in patients and corresponding mice transplanted with their PBMC. Expression of the EBV nuclear antigen 1 (EBNA1), the latent membrane protein 1 (LMP1), and LMP2, but not EBNA2, in the engrafted cells is consistent with the latency II program of EBV gene expression known in CAEBV. High levels of human cytokines, including IL-8, IFN-γ, and RANTES, were detected in the peripheral blood of the model mice, mirroring hypercytokinemia characteristic to both CAEBV and EBV-HLH. Transplantation of individual immunophenotypic subsets isolated from patients' PBMC as well as that of various combinations of these subsets revealed a critical role of CD4+ T cells in the engraftment of EBV-infected T and NK cells. In accordance with this finding, in vivo depletion of CD4+ T cells by the administration of the OKT4 antibody following transplantation of PBMC prevented the engraftment of EBV-infected T and NK cells. This is the first report of animal models of CAEBV and EBV-HLH that are expected to be useful tools in the development of novel therapeutic strategies for the treatment of the diseases

Population pharmacokinetics and pharmacodynamics of sitafloxacin in patients with community-acquired respiratory tract infections

An optimal dosage regimen of sitafloxacin was considered based on a pharmacokinetics and pharmacodynamics (PK–PD) analysis in patients with community-acquired respiratory tract infections (RTI). A population pharmacokinetic analysis of sitafloxacin was conducted using clinical data of five clinical pharmacology studies and one clinical PK–PD study in patients with RTIs. The pharmacokinetic parameters in individual patients were estimated by the Bayesian method to examine any correlation between pharmacokinetics and bacteriological efficacy. Efficacy data were obtained from the clinical PK–PD study, in which 50 or 100 mg sitafloxacin was administered twice daily for 7 days. In addition, an efficacy was simulated for a hypothetical dose regimen of 100 mg once daily. The fAUC(0–24h)/MIC and the fC(max)/MIC of sitafloxacin at a dose of 50 mg twice daily were 117.5 ± 78.0 and 7.3 ± 4.7 (mean ± SD), respectively. As a result of the univariate logistic regression analysis, the larger the value of fAUC(0–24h)/MIC or fC(max)/MIC becomes, the higher the bacteriological efficacies. The eradication rates for fAUC(0–24h)/MIC ≥ 30 and for fC(max)/MIC ≥ 2 were 96.4 % and 96.3 %, respectively. The PK–PD target values of sitafloxacin for the treatment of mild to moderate RTIs were considered to be fAUC(0–24h)/MIC ≥ 30 and fC(max)/MIC ≥ 2. The PK–PD parameters at the regimen of 50 or 100 mg twice daily in patients with RTIs reached the target values. Furthermore, a 100 mg once-daily regimen was expected to show similar efficacy based on the PK–PD simulations

Functional Differentiation among the Arabidopsis Phosphatidylinositol 4-Phosphate 5-Kinase Genes PIP5K1, PIP5K2 and PIP5K3

International audienceAbstract Phosphatidylinositol 4-phosphate 5-kinase (PIP5K) is involved in regulating various cellular processes through the signaling function of its product, phosphatidylinositol (4,5)-bisphosphate. Higher plants encode a large number of PIP5Ks forming distinct clades in their molecular phylogenetic tree. Although biological functions of PIP5K genes have been analyzed intensively in Arabidopsis thaliana, it remains unclear how those functions differ across clades of paralogs. We performed comparative functional analysis of the Arabidopsis genes encoding PIP5K1, PIP5K2 and PIP5K3, of which the first two and the last belong to closely related but distinct clades, to clarify their conserved and/or differentiated functions. Genetic analysis with their single and multiple mutants revealed that PIP5K1 and PIP5K3 have non-overlapping functions, with the former in total plant growth and the latter in root hair elongation, whereas PIP5K2 redundantly functions in both phenomena. This pattern of functional redundancy is explainable in terms of the overlapping pattern of their promoter activities. In transformation rescue experiments, PIP5K3 promoter-directed PIP5K1-YFP completely rescued the short-root-hair phenotype of pip5k3. However, PIP5K3-YFP could substitute for PIP5K1-YFP only partially in rescuing the severe dwarfism of pip5k1pip5k2 when directed by the PIP5K1 promoter. Phylogenetic analysis of angiosperm PIP5Ks revealed that PIP5K3 orthologs have a faster rate of diversification in their amino-acid sequences compared with PIP5K1/2 orthologs after they arose through a eudicot-specific duplication event. These findings suggest that PIP5K3 specialized to promote root hair elongation and lost some of the protein-encoded functions retained by PIP5K1 and PIP5K2, whereas PIP5K1 differentiated from PIP5K2 only in its promoter-directed expression pattern

Optical Properties of ZnO Nanoparticles Capped with Polymers

Optical properties of ZnO nanoparticles capped with polymers were investigated. Polyethylene glycol (PEG) and polyvinyl pyrrolidone (PVP) were used as capping reagents. ZnO nanoparticles were synthesized by the sol-gel method. Fluorescence and absorption spectra were measured. When we varied the timing of the addition of the polymer to the ZnO nanoparticle solution, the optical properties were drastically changed. When PEG was added to the solution before the synthesis of ZnO nanoparticles, the fluorescence intensity increased. At the same time, the total particle size increased, which indicated that PEG molecules had capped the ZnO nanoparticles. The capping led to surface passivation, which increased fluorescence intensity. However, when PEG was added to the solution after the synthesis of ZnO nanoparticles, the fluorescence and particle size did not change. When PVP was added to the solution before the synthesis of ZnO nanoparticles, aggregation of nanoparticles occurred. When PVP was added to the solution after the synthesis of ZnO nanoparticles, fluorescence and particle size increased. This improvement of optical properties is advantageous to the practical usage of ZnO nanoparticles, such as bioimagin