Modulation of Skin Collagen Metabolism in Aged and Photoaged Human Skin In Vivo

To the best of our knowledge, no study has been conducted to date to directly compare the collagen metabolism of photoaged and naturally aged human skin. In this study, we compared collagen synthesis, matrix metalloproteinase-1 levels, and gelatinase activity of sun-exposed and sun-protected skin of both young and old subjects. Using northern blot analysis, immunohistochemical stain, and Western blot analysis, we demonstrated that the levels of procollagen type I mRNA and protein in photoaged and naturally aged human skin in vivo are significantly lower than those of young skin. Furthermore, we demonstrated, by northern blot analysis, that the procollagen α1(I) mRNA expression of photoaged skin is much greater than that of sun-protected skin in the same individual. In situ hybridization and immunohistochemical stain were used to show that the expression of type I procollagen mRNA and protein in the fibroblasts of photoaged skin is greater than for naturally aged skin. In addition, it was found, by Western blot analysis using protein extracted from the dermal tissues, that the level of procollagen type I protein in photoaged skin is lower than that of naturally aged skin. The level of matrix metalloproteinase-1 protein and the activity of matrix metalloproteinase-2 were higher in the dermis of photoaged skin than in naturally aged skin. Our results suggest that the natural aging process decreases collagen synthesis and increases the expression of matrix metalloproteinases, whereas photoaging results in an increase of collagen synthesis and greater matrix metalloproteinase expression in human skin in vivo. Thus, the balance between collagen synthesis and degradation leading to collagen deficiency is different in photoaged and naturally aged skin

A childhood case of spinal tuberculosis misdiagnosed as muscular dystrophy

Tuberculosis is primarily a pulmonary disease, but extra-pulmonary manifestations are not uncommon, especially in children and adolescents. Ten percent of extra pulmonary tuberculosis localizes to the bones and joints, and 56% of such cases affect the spine. We treated a childhood case of spinal tuberculosis misdiagnosed as muscular dystrophy in a patient without specific constitutional symptoms. We report this case because the patient had an unusual presentation of spinal tuberculosis

SERS-Based Immunoassays for the Detection of Botulinum Toxins A and B Using Magnetic Beads

Rapid and sensitive detection of botulinum neurotoxins (BoNTs) is important for immediate treatment with proper antitoxins. However, it is difficult to detect BoNTs at the acute phase of infection, owing to its rarity and ambiguous symptoms. To resolve this problem, we developed a surface-enhanced Raman scattering (SERS)-based immunoassay technique for the rapid and sensitive detection of BoNTs. Magnetic beads and SERS nanotags as capture substrates and detection probes, respectively, and Nile Blue A (NBA) and malachite green isothiocyanate (MGITC) as Raman reporter molecules were used for the detection of two different types of BoNTs (types A and B), respectively. The corresponding limits of detection (LODs) were determined as 5.7 ng/mL (type A) and 1.3 ng/mL (type B). Total assay time, including that for immunoreaction, washing, and detection, was less than 2 h

Enhancing Laboratory Response Network Capacity in South Korea

Laboratory Response Network (LRN) laboratories help protect populations from biological and chemical public health threats. We examined the role of LRN biological laboratories in enhancing capacity to detect and respond to public health infectious disease emergencies in South Korea. The model for responding to infectious disease emergencies leverages standardized laboratory testing procedures, a repository of standardized testing reagents, laboratory testing cooperation among hospital sentinel laboratories and reference laboratories, and maintenance of a trained workforce through traditional and on-demand training. Cooperation among all network stakeholders helps ensure that laboratory response is an integrated part of the national response. The added laboratory testing capacity provided by the US Centers for Disease Control and Prevention LRN assets helps protect persons who reside in South Korea, US military personnel and civilians in South Korea, and those who reside in the continental United States

Clinical Outcomes of Secondary Prophylactic Granulocyte Colony-Stimulating Factors in Breast Cancer Patients at a Risk of Neutropenia with Doxorubicin and Cyclophosphamide-Based Chemotherapy

Doxorubicin and cyclophosphamide (AC)-based chemotherapy has been a standard regimen for early-stage breast cancer (ESBC) with an intermediate risk (10–20%) of febrile neutropenia (FN). Secondary prophylaxis of granulocyte colony-stimulating factor (G-CSF) is considered in patients receiving AC-based chemotherapy; however, relevant studies are limited. Here, we retrospectively reviewed the electronic medical records of 320 patients who completed adjuvant AC-based chemotherapy from September 2016 to September 2020. Approximately 46.6% of the patients developed severe neutropenic events (SNE) during AC-based chemotherapy. Secondary prophylaxis of G-CSF reduced the risk of recurrent SNE (p < 0.01) and the relative dose intensity (RDI) < 85% (p = 0.03) in patients who had experienced SNE during AC-based chemotherapy. Age ≥ 65 years (p = 0.02) and alanine aminotransferase (ALT) or aspartate aminotransferase (AST) > 60 IU/L (p = 0.04) were significant risk factors for RDI < 85%. The incidences of FN, grade 4 neutropenia, unscheduled hospitalization, and interruption to the dosing regimen were reduced in patients administered secondary prophylaxis with G-CSF (before vs. after administration: FN, 19.4% vs. 4.6%; grade 4 neutropenia, 86.1% vs. 14.8%; unscheduled hospitalization, 75.9% vs. 11.1%; interruption to the dosing regimen, 18.5% vs. 8.3%). This study indicated the importance of active intervention of G-CSF use to prevent recurrent SNE and improve clinical outcomes in patients with breast cancer who receive AC-based chemotherapy

H2O2 accumulation by catalase reduction changes MAP kinase signaling in aged human skin in vivo

To understand the molecular alterations occurring during the aging process, we compared mitogen-activated protein (MAP) kinase activities in the intrinsically aged and photoaged skins in the same individuals. Furthermore, we investigated the molecular events related to MAP kinase changes in intrinsically aged and photoaged skins. We found that extracellular-signal-regulated kinase (ERK) activity in photoaged skin was reduced, and that the activities of c-Jun N-terminal kinase (JNK) and p38 kinase were increased compared with intrinsically aged skin in the same individuals. Phospho-c-Jun levels and activator protein 1 activities in photoaged skin were also higher than in intrinsically aged skin. Moreover, catalase activity was found to be much reduced in primary dermal fibroblasts from photoaged skin, and as a result, H2O2 accumulated more in primary dermal fibroblasts in photoaged skin. In addition, treating primary dermal fibroblasts from photoaged skin with catalase reduced H2O2 levels, reversed aging-dependent MAP kinase changes, and inhibited matrix metalloproteinase (MMP)-1 expression. Our results indicate that the accumulation of reactive oxygen species due to catalase attenuation may be a critical aspect of the MAP kinase signaling changes that may lead to skin aging and photoaging in human skin in vivo. Thus, the induction and regulation of endogenous antioxidant enzymes including catalase may offer a strategy for preventing and treating skin aging