Molecular investigation of mutations in androgen receptor and 5‐alpha‐reductase‐2 genes in 46,XY Disorders of Sex Development with normal testicular development

In this study, we aimed to determine androgen receptor (AR) and SRD5A2 gene mutations in 45 patients characterised by 46,XY Disorders of Sex Differentiation (DSD) signs with normal testicular development referred to the Children's Medical Center from February 2015 to September 2017. Karyotype and sex hormone analyses were performed. Cytogenetic investigation showed that seven patients were 46,XX DSD, six patients were chromosomal DSD and 32 patients were 46,XY DSD. Eight exons of the AR gene and five exons of the SRD5A2 gene were amplified. Two cases were affected with androgen insensitivity syndrome (AIS) (missense mutation on exon 7, position c.3637 G>A: p.R841H and position c.3610 G>A: p.R832Q), one case was affected with 5‐alpha‐reductase deficiency type 2 (missense mutation at c.578A>G: p.N193S on exon 4), and 22 cases (88%) did not demonstrate AIS or 5α‐RD2 gene abnormality. Due to the great impact of these disorders on human lifestyle, evaluation of genes involved can improve genetic counselling and therapeutic management. We focused on the AR and SRD5A2 genes in patients with 46,XY DSDs with normal testicular development referred to the Children's Medical Center from all over the country to eventually culminate in a reliable prenatal diagnosis protocol at this major referral centre giving service to a great number of families with consanguineous marriages.     

Changes in macrophage phenotype and induction of epithelial‐to‐mesenchymal transition genes following acute Achilles tenotomy and repair

Tendon injuries occur frequently in physically active individuals, but the clinical outcomes for these injuries can be poor. In many injured tissues the repair process is orchestrated by two types of cells, macrophages and fibroblasts. Macrophages, which have both pro‐inflammatory (M1) and anti‐inflammatory (M2) phenotypes, can directly participate in tissue remodeling and direct the response of other cells through the secretion of cytokines and growth factors. In many organ systems, epithelial cells can trans‐differentiate into fibroblasts, which can then regenerate damaged ECM. This process is triggered via activation of epithelial‐to‐mesenchymal transition (EMT) signaling programs. Most tendons are surrounded by sheets of epithelial cells, and these tissue layers could provide a source of fibroblasts to repair injured tendons. To gain greater insight into the biology of tendon repair, we performed a tenotomy and repair in Achilles tendons of adult rats and determined changes in macrophage phenotype, and ECM‐ and EMT‐related genes over a 4‐week time course. The results from this study suggest that changes in macrophage phenotype and activation of EMT‐related programs likely contribute to the degradation and subsequent repair of injured tendon tissue. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:944–951, 2014.     

Development of the supraspinatus tendon‐to‐bone insertion: Localized expression of extracellular matrix and growth factor genes

The adult healing response of the rotator cuff tendon‐to‐bone insertion site differs from the ordered process of insertion site development. Healing is characterized by disorganized scar and a lack of fibrocartilage formation, in contrast to the well organized fibrocartilaginous transition which forms during the normal development of the tendon‐to‐bone insertion. The purpose of this study was to localize the expression of a number of extracellular matrix and growth factor genes during insertion site development in order to guide future strategies for augmenting adult rotator cuff healing. The rotator cuff was morphologically distinct at 13.5 dpc (days postconception). Neo‐tendon was evident as a condensation of cells adjacent to bone. The interface between tendon and bone did not form into a mature fibrocartilaginous insertion until 21‐days postnatally, based upon the appearance of four distinct zones with a mineralized humeral head. Fibroblasts of the supraspinatus tendon expressed type I collagen at all timepoints. Type II collagen was first expressed by chondrocytes in the fibrocartilage and mineralized fibrocartilage at 7 days and persisted in the mineralized fibrocartilage at 56 days. Type X collagen was first expressed by the chondrocytes in the mineralized fibrocartilage at 14 days and persisted in the mineralized fibrocartilage at 56 days. A shift from TGF‐β3 to TGF‐β1 expression occurred at 15.5 dpc. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1621–1628, 2007     

Excellent Clinical Outcomes From a National Donation‐After‐Determination‐of‐Cardiac‐Death Lung Transplant Collaborative

Donation‐after‐Determination‐of‐Cardiac‐Death (DDCD) donor lungs can potentially increase the pool of lungs available for Lung Transplantation (LTx). This paper presents the 5‐year results for Maastricht category III DDCD LTx undertaken by the multicenter Australian National DDCD LTx Collaborative. The Collaborative was developed to facilitate interaction with the Australian Organ Donation Authority, standardization of definitions, guidelines, education and audit processes. Between 2006 and 2011 there were 174 actual DDCD category III donors (with an additional 37 potentially suitable donors who did not arrest in the mandated 90 min postwithdrawal window), of whom 71 donated lungs for 70 bilateral LTx and two single LTx. In 2010 this equated to an “extra” 28% of donors utilized for LTx. Withdrawal to pulmonary arterial flush was a mean of 35.2 ± 4.0 min (range 18–89). At 24 h, the incidence of grade 3 primary graft dysfunction was 8.5%[median PaO₂/FiO₂ ratio 315 (range 50–507)]. Overall the incidence of grade 3 chronic rejections was 5%. One‐ and 5‐year actuarial survival was 97% and 90%, versus 90% and 61%, respectively, for 503 contemporaneous brain‐dead donor lung transplants. Category III DDCD LTx therefore provides a significant, practical, additional quality source of transplantable lungs.     

Evaluation of Hyphecan (1‐4,2‐acetamide‐deoxy‐B‐D‐glucan polymer) on wound healing in a rodent model

Objective: To evaluate the effect of an artificial skin Hyphecan (1‐4,2‐acetamide‐deoxy‐B ‐D ‐glucan polymer) on wound healing in a rodent model. Materials and Method: The prospective study was conducted at a basic science laboratory at a tertiary teaching hospital. Two 4 cm × 4 cm full‐thickness wounds were created on the dorsal surface of 10 Spraque–Dawley rats and covered with Hyphecan and Kaltostat, respectively. Wounds were examined and measured on days 4, 10, 21 and 28, and would continue after day 28 until healed up completely. Punch biopsies (3 mm) were taken on days 4, 10 and 28 for histological examination of the response of healing and repair. Results: Despite the fact that the wound healing rate was similar for both groups on days 4, 10, 21 and 28, the average healing time for the Hyphecan group (29.1 ± 1.7 days) was significantly shorter statistically (P = 0.03) than the Kaltostat group (30.7 ± 2.8 days). Conversely, the marked healing response elicited by Hyphecan on day 4 persisted on days 10 and 28 in contrast to Kaltostat, which had only a mild degree of healing response on days 10 and 28. The study suggests that wounds treated by Hyphecan heal faster than Kaltostat. Conclusion: The findings provide basic scientific evidence supporting the clinical use of Hyphecan in different wounds and might also reduce the cost of wound management as Hyphecan is cheaper than Kaltostat and requires a shorter treatment time.      

Investigation of High‐Speed Erythrocyte Flow and Erythrocyte‐Wall Impact in a Lab‐on‐a‐Chip

To better understand erythrocyte high‐speed motion, collision characteristics, and collision‐induced hemolysis probability in rotary blood pumps, a visual experimental investigation of high‐speed erythrocyte flow and erythrocyte‐wall collision in a lab‐on‐a‐chip was performed. The erythrocyte suspension was driven by a microsyringe pump connected to the microchip, and the erythrocyte flow and erythrocyte‐wall impact process were observed and imaged by an optical microscope and a high‐speed camera. Two types of microchips with different impact surfaces (flat and curved) were employed. The motion and deformation features before and after collision were studied in detail. The results show that erythrocytes not only move along the flow direction in the flow plane but also rotate and roll in three‐dimensional space. Erythrocytes keep discoid shape during the movement in the straight channel, but their deformations during collision are mainly classified into two types: erythrocyte structure is still stable and the erythrocyte performance can be ensured to a certain extent in the TypeA deformation, while the TypeB deformation makes the membrane more likely to fracture on the stretched side, increasing the probability of hemolysis. Furthermore, the movements and deformations of the erythrocytes after collision are analyzed and classified into two types: bouncing and slipping. Moreover, a simulation method for the flow in microchip was performed and validated through a comparison of the streamlines and experimental erythrocytes tracks, which can be further employed to predict the high‐speed blood flow, associated with collision process in mechanical blood pump.     

Role of Toll‐like receptor 4 signaling in cutaneous chronic graft‐versus‐host disease

Cutaneous damage is one of the characterized manifestations in chronic graft‐versus‐host disease (cGVHD). When local effective immunity in the skin is altered to a dysimmune reaction, cutaneous injuries occur. Toll‐like receptor 4 signaling is regarded as a central mediator of inflammation and organ injury. In this study, we found that TLR4 mRNA in peripheral blood from patients with cutaneous cGVHD was markedly increased compared with that from non‐GVHD patients and healthy controls. In addition, NF‐κB expression, TLR4 downstream signaling, and TLR4‐mediated cytokines, including IL‐6 and ICAM‐1, were upregulated. Moreover, ICAM‐1 was widely distributed in skin biopsies from patients with cutaneous cGVHD. We also found that LPS induced TLR4‐mediated NF‐κB activation and IL‐6 and ICAM‐1 secretion in human fibroblasts in vitro. Thus, TLR4, NF‐κB, IL‐6, and ICAM‐1 contribute to the inflammatory response that occurs in cutaneous cGVHD, indicating the TLR4 pathway may be a novel target for cutaneous cGVHD therapy.