Design and Ballistic Performance of Hybrid Plates Manufactured from Aramid Composites for Developing Multilayered Armor Systems.

In this study, the impact resistance of aramid fabric reinforced with shear thickening fluids (STFs), epoxy or polyurea elastomers is examined through ballistic tests. According to the ballistic test results, the aramid composite structure treated with polyurea elastomers absorbs the most impact energy per unit area density and has the best impact resistance. However, the occurrence of stress concentration during ballistic impact reduces the impact resistance of the aramid composite structure treated with epoxy. On the other hand, aramid fabric impregnated with STF improves structural protection, but it also increases the weight of the composite structure and reduces the specific energy absorption (SEA). The results of this study analyze the energy absorption properties, deformation characteristics, and damage modes of different aramid composites, which will be of interest to future researchers developing next-generation protective equipment.

Uremic Pruritus: From Diagnosis to Treatment.

Uremic pruritus, or chronic kidney disease-associated pruritus, is common, bothersome, and sometimes debilitating in patients with chronic kidney disease or end-stage renal disease. Due to its variable clinical manifestations, the diagnosis of uremic pruritus requires exquisite evaluation. Excluding itch resulting from other dermatological causes as well as other systemic conditions is essential for a proper diagnosis. The pathophysiology of uremic pruritus remains uncertain. Hypotheses including toxin deposition, immune system dysregulation, peripheral neuropathy, and opioid imbalance are supposed. This review summarizes the way to accurately diagnose uremic pruritus and describes the latest treatment options.

Skin infection by Mycobacterium farcinogenes-senegalense group in an immunocompetent patient: a case report.

BACKGROUND: Mycobacterium farcinogenes-senegalense group mostly cause bovine farcy, which rarely infect human beings. We reported one case of cutaneous Mycobacterium farcinogenes-senegalense group infection in an immunocompetent victim. CASE PRESENTATION: A 66-year-old Taiwanese woman with hypertension developed tender nodules on her left dorsal foot for 2 months. Tissue culture identified Mycobacterium farcinogenes-senegalense group. The lesion was treated successfully with clarithromycin and sulfamethoxazole/trimethoprim, followed by surgical excision. CONCLUSIONS: Mycobacterium farcinogenes-senegalense group infection should be considered as a potential pathogen of skin infection in immunocompetent patients.

Impaired Wnt/beta-catenin and protein patched homolog 1 signaling in extraocular sebaceous carcinoma: A clinical and histopathological study.

Sebaceous carcinoma (SC) is a rare malignant neoplasm with sebaceous differentiation. SC is classified into eyelid and extraocular SC clinically. Most studies have focused on the eyelid SC in terms of pathogenesis, treatment, and prognosis. In skin, Wnt/beta-catenin and hedgehog signaling are two major pathways in sebaceous differentiation. We aimed to characterize the clinical and histopathological features of extraocular SC and to measure the expression of beta-catenin, lymphoid enhancer-binding factor 1 (LEF1), sonic hedgehog (Shh), and protein patched homolog 1 (PTCH) in extraocular SC. Ten cases of extraocular SC were identified from 2007 to 2020. The clinical features, microscopic findings, and prognosis were analyzed. Immunohistochemical stain for beta-catenin, LEF1, Shh, and PTCH were performed in extraocular SC and other benign sebaceous tumors including sebaceous hyperplasia, sebaceous adenoma, and sebaceoma. The male:female ratio was 4:6. The median onset age was 73.5 years (range, 43-88). Seven patients out of 10 were diagnosed after 60 years. Most extraocular SC were located on the head and neck with indurated plaque. Two patients had concurrent internal cancers and three patients showed lymph node metastasis at time of presentation. Five-year overall-survival was 40%. Beta-catenin was expressed membranously in all sebaceous hyperplasia, but was expressed variably in extraocular SC (1/5). While LEF1 was unequivocally expressed in normal hair follicles, LEF1 expression was absent in all extraocular SC and benign sebaceous tumors. Regarding the sonic hedgehog signaling, Shh and PTCH were all expressed in the cytoplasm of sebaceous hyperplasia, sebaceous adenoma, and sebaceoma. In contrast, PTCH was absent in all cases of extraocular SC and only 50% of the extraocular SC expressed cytoplasmic Shh. To conclude, extraocular SC commonly affects facial skin in the elderly. Inactivated Wnt/beta-catenin and aberrant hedgehog pathway may contribute to the carcinogenesis of extraocular SC. Further studies may be required to elucidate the causative mechanism of these pathways in extraocular SC.

"Spade sign" and inflammation/fibrosis limited to the upper and mid-dermis as the pathognomonic features of acne keloidalis.

Acne keloidalis (AK) is one of the primary cicatricial alopecias and predominantly affects men of African descent. Reports in Asians are scant. This study aimed to retrospectively review the clinical and histopathological features of AK patients in southern Taiwan and identify the pathognomonic features of AK. There were 15 patients with histopathologically confirmed AK in National Cheng Kung University Hospital between 1988 and 2018. The median onset age was 24 years (range, 14-71). The male : female ratio was 14:1. In the acute stage of AK, the lymphocytic and neutrophilic peri-infundibular inflammatory infiltrates with microabscess formation and edema corresponded to the clinical finding of isolated papules or pustules. Subsequently, the inflammatory infiltrates involved the mid-dermis and the isthmus of hair follicles. The "spade sign", a thin and dilated space resembling the shape of a balloon or spade symbol of playing cards at the level of lower isthmus, was identified in eight biopsies from five patients and may be a pathognomonic sign in the subacute stage of AK. At the chronic stage, the segments of hair shafts remained in the upper to mid-dermis and induced chronic inflammation and extensive fibrosis, resulting in the clinical keloid-like appearance. The restriction of inflammation and fibrosis in the upper to mid-dermis was another unique and pathognomonic feature of AK.

Primary scarring alopecia: A retrospective study of 89 patients in Taiwan.

Primary scarring alopecia (PSA) is caused by irreversible damage to the hair epithelial stem cells that reside in hair follicles. There is limited published work regarding PSA amongst the Asian population. The aim of this study was to evaluate the clinical features and to characterize the subtypes of PSA in southern Taiwan. In this retrospective case series, we reviewed 89 patients with pathology-confirmed PSA. The data was collected from National Cheng Kung University Hospital between 1988 through 2016. The clinical and histological data were reviewed, and the patients were characterized into different subtypes of PSA based on the clinical features and histological findings. We noted seven different subtypes of PSA. The most common type was dissecting cellulitis (DC) (30.3%), followed by lichen planopilaris (LPP) (23.5%), central centrifugal cicatricial alopecia (CCCA) (12.4%) and acne keloidalis nuchae (AKN) (12.4%). The other subtypes include folliculitis decalvans (FD), discoid lupus erythematosus (DLE) and pseudopelade of Brocq (PPB). Interestingly, FD, DC and AKN were more common in males, while CCCA, LPP, DLE and PPB had a female predominance. The mean age of patients with DLE, DC and AKN were younger, while patients with CCCA, LPP, PPB and FD tend to be older. The pattern of hair loss was more likely to be unifocal-ragged border in CCCA and DLE, multifocal-interconnected in LPP and FD, and multifocal-separated in DC. The pathogenesis of PSA may be influenced by sex, age and genetic background. It is important to identify the hair loss pattern to differentiate the subtypes of PSA.