A modified partial wedge-shaped metaphyseal ulnar osteotomy for the treatment of ulnar impaction syndrome with reverse oblique sigmoid notch.

We describe a modified metaphyseal ulnar osteotomy to treat ulnar impaction syndrome with a reverse oblique sigmoid notch. Based on a computational analysis of radiographs, a modified wedge metaphyseal ulnar osteotomy was devised with its apex positioned at the ulnar styloid base to avoid impaction between the sigmoid notch and ulnar head. Subsequently, nine patients with ulnar impaction syndrome and a reverse oblique sigmoid notch underwent this operation, combined with arthroscopic exploration and transosseous triangular fibrocartilage complex repair. The mean follow-up was 14 months. All patients achieved bone union within 5 weeks, with no degenerative changes being observed during the follow-up assessments. The final follow-up assessments revealed decreases in ulnar variance and in the scores for Visual Analogue Scale, Quick Disabilities of the Arm, Shoulder and Hand questionnaire and the Patient-Rated Wrist Evaluation. All patients achieved excellent or good grades on the Modified Mayo Wrist Score. This technique is effective in treating the ulnar impaction syndrome with a reverse oblique sigmoid notch.Level of evidence: IV.

Electrical stimulation promoting the angiogenesis in diabetic rat perforator flap through attenuating oxidative stress-mediated inflammation and apoptosis.

Background: Skin flap transplantation is one of the effective methods to treat the diabetes-related foot ulceration, but the intrinsic damage to vessels in diabetes mellitus (DM) leads to the necrosis of skin flaps. Therefore, the discovery of a non-invasive and effective approach for promoting the survival of flaps is of the utmost importance. Electrical stimulation (ES) promotes angiogenesis and increases the proliferation, migration, and elongation of endothelial cells, thus being a potential effective method to improve flap survival. Objective: The purpose of this study was to elucidate the mechanism used by ES to effectively restore the impaired function of endothelial cells caused by diabetes. Methods: A total of 79 adult male Sprague-Dawley rats were used in this study. Gene and protein expression was assessed by PCR and western blotting, respectively. Immunohistochemistry and hematoxylin-eosin staining were performed to evaluate the morphology and density of the microvessels in the flap. Results: The optimal duration for preconditioning the flap with ES was 7 days. The flap survival area percentage and microvessels density in the DMES group were markedly increased compared to the DM group. VEGF, MMP2, and MMP9 protein expression was significantly upregulated. ROS intensity was significantly decreased and GSH concentration was increased. The expression of IL-1ß, MCP­1, cleaved caspase-3, and Bax were downregulated in the DMES group, while TGF-ß expression was upregulated. Conclusions: ES improves the angiogenesis in diabetic ischemic skin flaps by attenuating oxidative stress-mediated inflammation and apoptosis, eventually increasing their viability.

Customizing Anterolateral Thigh Flap With Magnetic Resonance Angiography Differential Subsampling With Cartesian Ordering Imaging for Individualized Reconstruction of Extremity Defects.

INTRODUCTION: Magnetic resonance angiography (MRA) with the differential subsampling with cartesian ordering (DISCO) imaging technique is rarely used in anterolateral thigh (ALT) flap. In our series, MRA DISCO imaging technique is used as a tool to customize ALT flaps. The aim of this study was to report the accuracy of cutaneous perforators identified by the MRA DISCO imaging. METHODS: Nineteen patients underwent the MRA DISCO imaging for perforator mapping before the ALT flap transfer. A total of 38 ALT regions were studied on the MRA DISCO images. Flap thinning was performed under the guidance of MRA DISCO imaging. RESULTS: The lateral circumflex femoral artery (LCFA) most commonly stems from the deep femoral artery (84.2%), followed by the common femoral artery (15.8%). The average number of perforator vessels per LCFA was 10.2 ± 1.7. The distinct oblique branch was observed in 16 out of the 38 ALT regions (42.1%). Among the 19 ALT flaps harvested, 5 were septocutaneous perforator flaps and 14 musculocutaneous perforator flaps. Ten were harvested based on the descending branch, and 3 used the oblique branch as the flap vascular pedicle. In addition, the displayed course and types of perforator vessels on the DISCO images of the 18 skin flaps were consistent with the intraoperative findings, with an accuracy of 94.7%. CONCLUSIONS: The state of the cutaneous perforators of LCFA can be identified on the MRA DISCO images. The 3D-CE-MRA DISCO imaging is a practical method, which can ameliorate the design and customization of ALT flap for an individualized reconstruction.

Effect of percutaneous and arthroscopically assisted osteosynthesis of talar body fractures.

BACKGROUND: Talar fractures are relatively uncommon, and the complex anatomy of the talus impedes their visualization, reduction, and fixation without performing an arthrotomy or osteotomy. To date, few studies have evaluated the complications of arthroscopically assisted percutaneous talar osteosynthesis. This clinical retrospective study aimed to investigate the effectiveness of this procedure according to the complications and functional outcomes. METHODS: Arthroscopically assisted percutaneous talar osteosynthesis was performed in 15 patients (10 men and 5 women) with 16 fractures (one bilateral). The mean patient age was 31 years (range, 14-52 years). The Sneppen classification of the fractures was type II in 14 cases and type III in 2 cases. RESULTS: Fifteen patients were followed up for 36 months on average (range, 18-65 months). No skin infection, osteomyelitis, or skin necrosis was observed in any patient. During the follow-up, no bony non-union or delayed union was found. At the final follow-up, 2 out of the 15 patients (13.3%) had peri-talar osteoarthritis. The ankle-hindfoot pain was absent in 11 patients (12 ankles) and mild in 4 patients. Based on the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale, functional results were excellent in 7 ankles and good in 9 ankles. The mean AOFAS ankle-hindoot score of the patients was 85.7 (range, 79-93). CONCLUSION: Arthroscopically assisted percutaneous talar osteosynthesis is a reliable and feasible technique that yields good clinical outcomes.

Daphnetin contributes to allergen-induced Th2 cytokine expression and type 2-immune responses in atopic dermatitis and asthma.

Daphne koreana Nakai is a cherished medicinal plant in the Changbai Mountain region of China. It can be incorporated into medicinal meals and used for various skin diseases by infiltrating liquor. Daphnetin (7,8-dihydroxycoumarin, Dap.) is a main constituent of D. koreana Nakai, which has been used to treat inflammatory conditions and immune disorders due to its numerous pharmacological activities, including anti-oxidant, anti-inflammatory, analgesic, etc. Atopic dermatitis (AD) and allergic asthma are typical diseases of type 2-immune responses. In the present study, the therapeutic potential of Dap. against AD and allergic asthma was investigated using animal and cell experiments. AD-like lesions were induced by repeated application of 1-chloro-2,4-dinitrobenzene (DNCB) to the shaved dorsal skin of BALB/c mice. Ovalbumin (OVA) induction was utilized to establish a mouse asthma model. A passive cutaneous anaphylaxis (PCA) mouse ear model and immunoglobulin E (IgE)/bovine serum albumin (BSA)-stimulated RBL-2H3 cells were used for in vitro assays. The skin lesions and serum and tissue homogenates of the mice were analyzed using histological analysis, immunohistochemistry (IHC) and enzyme-linked immunosorbent assay (ELISA), respectively, in order to investigate the anti-AD effects of Dap. Histological analysis was performed on the allergic asthma model to observe inflammatory cell infiltration in the lung tissues. Total IgE and OVA-specific IgE in the serum were measured by ELISA. The levels of inflammatory cytokines in BALF were detected by ELISA. In addition, ELISA and western blotting were performed for the in vitro analysis of RBL-2H3 cells. The results showed that Dap. inhibited the development of DNCB-induced AD-like lesions in the BALB/c mice by reducing the severity of the lesions, epidermal thickness and mast cell infiltration; this was accompanied by reduced levels of IgE and inflammatory cytokines [interleukin (IL)-4, IL-5, IL-9, IL-13, IL-33 and thymic stromal lymphopoietin (TSLP)]. In the allergic asthma model, Dap. reduced the number of infiltrated inflammatory cells in the lung tissues. Moreover, the levels of total serum IgE and OVA-specific IgE were reduced in the high daphnetin dose groups (Dap., -100 mg kg-1). Dap. administered at a dose of -100 mg kg-1 decreased the levels of inflammatory cytokines (IL-4, IL-5, IL-9, IL-13, IL-33 and TSLP in BALF). Furthermore, Dap. administered to IgE-sensitized mice effectively attenuated the IgE-triggered PCA reaction. In vitro, Dap. decreased the expression levels of histamine, IL-4, IL-6, IL-13, MIP-1α and INF-α, and reduced the protein expression levels of phosphorylated MAPKs, P-Lyn and P-syk in the RBL-2H3 cells. Therefore, Dap. can be represented as a potential therapeutic strategy for the treatment of allergic inflammatory conditions via immunoregulation.

Plantar and dorsal approaches for excision of morton's neuroma: a comparison study.

BACKGROUND: Morton's neuroma is a painful enlargement of the plantar digital nerve between the metatarsal heads that causes pain of the forefoot. Several approaches have been used to treat Morton's neuroma, each of them having distinct advantages and disadvantages. OBJECTIVES: The purpose of this study was to investigate and compare the clinical outcomes of neurectomy in the treatment of Morton's neuroma through plantar and dorsal approaches. MATERIALS AND METHODS: A total of 20 patients with a mean age of 48.5 ± 13.0 years (range: 19-66 years) who underwent excision of a Morton's neuroma that did not respond to conservative treatment were retrospectively analysed from June 2014 to June 2021. All the neurectomies were performed using a plantar or dorsal approach. Outcomes were evaluated using visual analogue scale (VAS) scores, American Orthopedic Foot and Ankle Society (AOFAS) scores, the Foot and Ankle Ability Measure (FAAM), and complications. The appearance index (AI) was also used to assess the influence of foot appearance on the quality of life after surgery. RESULTS: Eight patients underwent neurectomy by the dorsal approach, and 12 patients underwent neurectomy by the plantar approach. The average follow-up time was 28.9 ± 12.9 months (range: 15-72 months). No statistically significant difference was found between the dorsal and plantar approach groups with respect to postoperative pain measured by the VAS score. The postoperative AOFAS scores and FAAM outcomes were not significantly different between the groups. The complications reported in the dorsal approach group were significantly less than those of the plantar group, mainly discomfort in wearing shoes. The AI of the plantar group and the dorsal group were significantly different. CONCLUSION: The excision of the Morton's neuroma by both the dorsal and plantar approach resulted in satisfactory outcomes. However, the foot appearance after surgery by the plantar approach had less influence on the quality of life than that using the dorsal approach. Our recommendation is that surgeons should choose the approach they are most familiar with and with which they are most confident in performing. In addition, the plantar approach is recommended if the patient needs a better appearance.

Differential Subsampling with Cartesian Ordering Contrast-Enhanced Magnetic Resonance Angiography for the Preoperative Assessment of Anterolateral Thigh Flap.

OBJECTIVE: To investigate the clinical application of differential subsampling with Cartesian ordering (DISCO) contrast-enhanced (CE) magnetic resonance angiography for anterolateral thigh (ALT) flap transplantation, using operative findings as a reference. MATERIALS AND METHODS: Thirty patients (21 males and nine females; mean age ± standard deviation, 45.5 ± 15.6 years) who were scheduled to undergo reconstruction with ALT flaps between June 2020 and June 2021 were included in the prospective study. Before ALT flap transplantation, patients were scanned using CE-DISCO imaging. All acquired DISCO images of the 60 lower limbs (both sides from each patient) were analyzed using maximum intensity projection and volume rendering methods. Two experienced radiologists were employed to examine the patterns of the lateral circumflex femoral artery (LCFA), its branches, and perforators and their skin termini, which were compared with the operative findings. RESULTS: Using CE-DISCO, the patterns of the LCFA and its branches were clearly identified in all patients. Four different origins of the LCFA were found among the 60 blood vessels: type I (44/60, 73.3%), type II (6/60, 10.0%), type III (8/60, 13.3%), and type IV (2/60, 3.3%). Owing to a lack of perforators entering the skin, two patients did not undergo ALT flap transplantation. For the remaining 28 patients, the ALT flaps in 26 patients were successfully operated without flap re-selection during the operation, while the remaining two patients underwent other surgical procedures due to the thin diameter of the perforator or injury of the perforator during the operation. The success rate of flap transplantation was 92.8% (26/28). All transplanted flaps exhibited good blood supply and achieved primary healing without infection or delayed healing. CONCLUSION: CE-DISCO imaging can be an effective method for preoperative perforator imaging before ALT flap transplantation.

Correlation of vascular change with TRPV1, TRPV4, and TRPA1 in a rat model of inferior gluteal artery perforator flap.

Maximum survival area after perforator flap elevation is mainly achieved through vasodilation and angiogenesis, and endothelial Ca2+ signals play a pivotal role in both of them. Transient receptor potential (TRP) channels modulate many endothelial cell functions via mediating the extracellular Ca2+ entry. This study aims to investigate the correlation of TRPV4, TRPV1, and TRPA1 with vascular change after the inferior gluteal artery perforator flap elevation. A total of 50 adult male SD rats were used in this study. Ten rats were used in the part one to assess the flap viability on postoperative day 7. Twenty rats were used in the part two to evaluate blood flow change after flap elevation. The correlation of vascular change with TRPV1, TRPV4, and TRPA1 protein changes was investigated in 20 rats in the part three. The mean flap survival area percentage was 55 ± 5.7%. Blood flow in the overall flap and Zone II after the flap elevation markedly increased from the postoperative day 3. The most marked change of the vasodilation occurred on Days 3 and 5 after flap elevation. The angiogenesis occurred on Day 5 after flap elevation and the microvessel density peaked also on Day 5. Moreover, TRPA1 expression showed a trend towards continuous reduction over time. The expression of TRPV1 and TRPV4 reached the peak value on Day 3. The endothelial NO synthase expression showed an increasing trend at first, followed by a reduction over time, while VEGF expression reached the peak value on Day 3. The vascular changes after flap elevation might be associated with the changes in TRPV4, TRPV1, and TRPA1.

Mothers caring experiences of children with congenital hand or foot abnormalities: A phenomenological study.

PURPOSE: To explore the mothers' caring experiences of children with congenital hand or foot abnormalities, and to inform the development of tailored intervention strategies to improve the mothers' well-being. DESIGN AND METHODS: A qualitative study design was used. A purposive sample of 23 women whose children had congenital abnormalities of the hand or foot were enrolled. Semi-structured, in-depth interviews were conducted from December 2019 to May 2020. The Colaizzi's phenomenological approach was used for data analysis. RESULTS: Data analysis revealed four main themes: (a) dynamic negative affect; (b) low health literacy; (c) mothers' need for support; and (d) the shift in social activity and family role. Eleven subthemes were involved in these themes. CONCLUSIONS: Women whose children have abnormal hands or feet have complicated care experiences and are under tremendous psychological pressure. Some mothers also encounter financial difficulties. PRACTICE IMPLICATIONS: This study assessed the psychological impact on mothers of children with congenital hand or foot abnormalities. Our findings illustrate the needs of mothers, and call attention to this specific group. The findings may help inform healthcare and social interventions to facilitate the recovery of the affected children and cater to the needs of these families. Healthcare providers should provide adequate instructions to the parents regarding the provision of home management care following discharge from the hospital.

Flow-mediated vasodilation through mechanosensitive G protein-coupled receptors in endothelial cells.

Currently, endothelium-dependent vasodilatation involves three main mechanisms: production of nitric oxide (NO) by endothelial nitric oxide synthase (eNOS), synthesis of prostanoids by cyclooxygenase, and/or opening of calcium-sensitive potassium channels. Researchers have proposed multiple mechanosensors that may be involved in flow-mediated vasodilation (FMD), including G protein-coupled receptors (GPCRs), ion channels, and intercellular junction proteins, among others. However, GPCRs are considered the major mechanosensors that play a pivotal role in shear stress signal transduction. Among mechanosensitive GPCRs, G protein-coupled receptor 68, histamine H1 receptors, sphingosine-1-phosphate receptor 1, and bradykinin B2 receptors have been identified as endothelial sensors of flow shear stress regulating flow-mediated vasodilation. Thus, this review aims to expound on the mechanism whereby flow shear stress promotes vasodilation through the proposed mechanosensitive GPCRs in ECs.

Mimical reconstruction and aesthetic repair of the nail after resection of subungual melanocytic nevus.

BACKGROUND: This study aimed to report the outcomes of mimical reconstruction and aesthetic repair of the nail. METHODS: When the pigmented bands were more than 1/2 the width of the whole nail, mimical reconstruction of the nail was performed, with a lateral toe pulp island flap covering the wound via the subcutaneous channel. If the pigmented bands were 1/4 to 2/5 the width of the entire nail, aesthetic repair of the nail was carried out by split-thickness excision under a microscope. RESULTS: The average age of patients at the time of surgery was 14.5 years. Five patients had lesions on their toes, while three had lesions on their fingers. There were no post-operative complications. All toenails of the five patients who had undergone mimical reconstruction exhibited a well-settled flap. The nails of the three patients who underwent aesthetic repair displayed no nail malnutrition or deformity, and all nails had an aesthetic appearance. CONCLUSIONS: Both mimical reconstruction and aesthetic repair of the nail following resection of subungual melanocytic nevus are reliable and feasible. The "like tissue" repairs of complex nail defects appear to be satisfactory. All patients had excellent aesthetic outcomes. LEVEL OF EVIDENCE: V.

A Novel Medial Malleolar Osteotomy Technique for the Treatment of Osteochondral Lesions of the Talus.

BACKGROUND: The current techniques for medial malleolar osteotomy may lead to posterior tibial tendon injury and have a high rate of malunion. PURPOSE: To describe a novel partial step-cut medial malleolar osteotomy technique and evaluate its technical feasibility and its advantages compared with traditional methods. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: The novel technique consisted of osteotomy of the anterior one-third to two-thirds of the medial malleolus. A total of 19 ankles (18 patients) with osteochondral lesions of the talus underwent the novel osteotomy technique before osteochondral reconstruction. All patients were evaluated for more than 2 years. Radiographs were analyzed for postoperative displacement and malunion, and postoperative ankle function was evaluated according to the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scale and the visual analog scale (VAS) for pain. RESULTS: The partial step-cut osteotomy technique was able to provide adequate intra-articular exposure without disturbing the posterior tibial tendon. The 19 ankles healed at a mean of 7.3 ± 1.5 weeks (range, 6-12 weeks). There was slight incongruence in 4 ankles, with a displacement of 1.0 ± 0.1 mm proximally and 0.3 ± 0.1 mm medially. The mean postoperative AOFAS and VAS scores improved compared with preoperatively, from 54.2 ± 12.1 to 84.6 ± 6.6 and from 6.4 ± 1.0 to 1.8 ± 1.3, respectively (P < .001 for both). No intraoperative tendon injuries were observed. CONCLUSION: Results indicated that partial step-cut osteotomy is a reliable and effective method for providing enough exposure, avoiding displacement after reduction, and not disturbing the anatomic structures behind the medial malleolus.

Role of TRPV4 channel in vasodilation and neovascularization.

The transient receptor potential vanilloid type 4 (TRPV4) channel, a Ca2+ -permeable nonselective cation channel, is widely distributed in the circulatory system, particularly in vascular endothelial cells (ECs) and smooth muscle cells (SMCs). The TRPV4 channel is activated by various endogenous and exogenous stimuli, including shear stress, low intravascular pressure, and arachidonic acid. TRPV4 has a role in mediating vascular tone and arterial blood pressure. The activation of the TRPV4 channel induces Ca2+ influx, thereby resulting in endothelium-dependent hyperpolarization and SMC relaxation through SKCa and IKCa activation on ECs or through BKCa activation on SMCs. Ca2+ binds to calmodulin, which leads to the production of nitric oxide, causing vasodilation. Furthermore, the TRPV4 channel plays an important role in angiogenesis and arteriogenesis and is critical for tumor angiogenesis and growth, since it promotes or inhibits the development of various types of cancer. The TRPV4 channel is involved in the active growth of collateral arteries induced by flow shear stress, which makes it a promising therapeutic target in the occlusion or stenosis of the main arteries. In this review, we explore the role and the potential mechanism of action of the TRPV4 channel in the regulation of vascular tone and in the induction of neovascularization to provide a reference for future research.

Vascularized Capitate Transposition for the Treatment of Stage IIIB Kienböck Disease.

PURPOSE: The treatment of Kienböck disease (KD) continues to be controversial. In this study, we report the long-term follow-up outcomes of patients who were diagnosed with stage IIIB KD treated with vascularized capitate transposition. METHODS: A total of 16 patients were retrospectively reviewed. Baseline clinical information was extracted from medical records, and wrist function was clinically evaluated, including x-ray images. RESULTS: At the final follow-up, wrist pain was severe in 0 patients, moderate in 2 patients, mild in 5 patients, and absent in 9 patients. The mean postoperative active flexion and extension of the affected wrist was significantly improved after surgery compared with before surgery. The postoperative and preoperative mean grip strength was 35 kg and 27 kg, respectively. The Disabilities of the Arm, Shoulder, and Hand score was significantly improved after surgery compared with before surgery. CONCLUSIONS: Vascularized capitate transposition for the treatment of Lichtman stage IIIB KD is feasible and associated with improvements in wrist function and pain. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Visualizing the Pharmacologic Preconditioning Effect of Botulinum Toxin Type A by Infrared Thermography in a Rat Pedicled Perforator Island Flap Model.

BACKGROUND: Surgical delay can improve flap viability, leading to vasodilation, neovascularization, and vessel reorganization. Experiments suggest a similar positive effect of botulinum toxin type A on pedicled flap viability. However, whether it may convert choke anastomoses into true anastomoses and how to identify the optimal timing for flap transfer remain unclear. METHODS: One hundred fifty-four Sprague-Dawley rats were divided into a control group, three saline injection groups, and three botulinum toxin type A injection groups defined by time of injection (2, 3, and 4 weeks before flap harvest). A pedicled 11 × 3-cm flap was marked on the unilateral dorsum of each rat. Before flap harvest, the flap donors were assessed by infrared thermal imaging, postmortem arteriography, immunohistochemical staining of CD31, and enzyme-linked immunosorbent assay. Flap survival area percentage was measured on postoperative day 7. RESULTS: In the control and saline groups, infrared thermography showed three independent white hotspots interspaced by red zones over flaps, whereas it presented a continuous white band in the botulinum toxin type A groups. There was a significant increase in flap survival area, flap surface temperatures, numbers of identifiable vessels in the choke zones, microvascular density, and vascular endothelial growth factor concentration in the botulinum toxin type A groups. CONCLUSIONS: Botulinum toxin type A can convert choke anastomoses into true anastomoses, and its preconditioning effect cannot increase over time; it is appropriate to choose the timing point when the infrared thermal images show a continuous white band existing over flaps for flap transfer.

Genomic Analysis Of A KPC-2-Producing Klebsiella Pneumoniae ST11 Outbreak From A Teaching Hospital In Shandong Province, China.

PURPOSE: Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae bacteria causes nosocomial infections worldwide. However, KPC-producing K. pneumoniae outbreak has never been reported in Shandong Province, China. The purpose of our study was to elucidate the epidemiological and drug resistance mechanisms of KPC-producing K. pneumoniae strains collected from a large teaching hospital in Shandong during the outbreak. Moreover, we attempted to characterize the genetic environment and phylogenetic analysis of bla KPC-2 in outbreak isolates. METHODS: We monitored a 64-day outbreak of infection in a general hospital in Shandong Province, and the bacteria causing the infection were all ST11-type K. pneumoniae. The genotype correlation of KPC-producing K. pneumoniae isolates was assessed by whole-genome sequencing (WGS) phylogenetic analysis. Subsequent studies included antibiotic susceptibility testing, multilocus sequence typing (MLST) and S1-pulsed-field gel electrophoresis (S1-PFGE), Southern blot hybridization. RESULTS: From February 1, 2018 to April 5, 2018, 14 KPC-producing K. pneumoniae isolates from different wards were collected. All 14 isolates were resistant to carbapenems and carried the extended-spectrum ß-lactamase (ESBL) gene as well as fosA, and sul genes. Whole-genome analysis showed that all 14 the outbreak isolates were all ST11 type. The bla KPC-2 carrying plasmids were all belong to IncFIIK2 type, and the size ranged from 94 kb to 368 kb. CONCLUSION: As far as we know, this report first describes the genomics characterization of KPC-2-producing K. pneumoniae outbreak isolates from Shandong Province, China. In our study, these isolates appeared to be cloned, and ST11 K. pneumoniae was the major clone caused the outbreak. Therefore, routine surveillance of such strains in this region is urgently warranted.

A brand-new generation of fluorescent nano-neural tracers: biotinylated dextran amine conjugated carbonized polymer dots.

The anterograde neuroanatomical tracing technique plays a crucial role in studying and charting the complex interconnections of the nervous system. But there are several major limitations for traditional neural tracers, such as complex immunohistochemical staining procedures, low fluorescence intensity and quick fluorescence quenching. Carbon dots (CDs) as fluorescent bio-probes have been widely used in the biological studies due to their superior optical properties, excellent chemical stability, low toxicity, and easy modifications. In this study, biotinylated dextran amine (BDA) and red fluorescent carbonized polymer dots (CPDs) are successfully conjugated to develop a brand-new generation of fluorescent nano-neural tracers: BDA-CPDs. They are successfully applied as fluorescent probes for in vitro and in vivo bioimaging. In vitro biodistribution of BDA-CPDs shows that they distribute mainly in lysosomes and endoplasmic reticulum. Moreover, two metabolic pathways of BDA-CPDs are found through the investigation of in vivo biodistribution of BDA-CPDs. Furthermore, they can be taken up and anterogradely transported by neurons within the peripheral nervous system of rats. Our results suggest that BDA-CPDs have many advantages over traditional tracers, such as low toxicity, high photoluminescence intensity, excellent photostability and easy procedures. Anterograde pathway tracing with BDA-CPDs is a simple, direct and economical way of studying the connections in the nervous system. Therefore, BDA-CPDs are reliable and valuable fluorescent anterograde neural tracers.

Visualized identification of the maximal surgical delay effect in a rat flap model.

Currently, experimental evidence suggests that the surgical delay can increase flap survival area, but its effect may decrease if the optimal delay period is missed. The aim of this study is to establish a sensitive and objective modality based on the visualized and individualized infrared thermography for identifying the maximal surgical delay effect. A rectangular three-angiosome flap was designed on the unilateral dorsum of the rat. Ninety-six rats were randomly divided into six groups according to the various delay time. Both the relative temperature and the relative temperature ratio were measured by the infrared thermography. Arterial density, number of vessels >0.1 mm in diameter, microvessel density, VEGF concentration, and flap viability were measured. Receiving operating characteristic curve with the highest Youden-Index was used to detect and identify an optimal cutoff point of the relative temperature ratio in the maximal surgical delay effect. The criteria for identifying the flap maximum delay effect based on the infrared thermography included the surface of the postdelayed flaps presented white color (higher temperature) instead of the red and white pattern of the normal skin and the optimal cutoff point of the relative temperature ratio was ≥1.17 with a sensitivity of 84.6% and a specificity of 77.3%. Instead, the sensitivity and specificity of the conventional method based on the delay time were 38.5 and 90.9%, respectively. Infrared thermal imaging can accurately identify the maximum delay effect when combined with the relative temperature ratio.

Effect of Endogenous Vascular Endothelial Growth Factor on Flap Surgical Delay in a Rat Flap Model.

BACKGROUND: Experimental evidence suggests that endogenous vascular endothelial growth factor (VEGF) may play a major role in the surgical delay phenomenon. The purpose of this study was to investigate the effect of endogenous VEGF on flap surgical delay. METHODS: A total of 82 adult male Sprague-Dawley rats with an average weight of 330 g were used for these experiments. These experiments were then conducted in two parts. In part 1, 32 rats were used to assess the effectiveness of VEGF inhibitor through Western blot assay and enzyme-linked immunosorbent assay. In part 2, 50 rats were used to investigate the effect of VEGF on flap surgical delay by means of arteriography, histologic analysis, and flap viability. RESULTS: The VEGF protein inhibition ratio reached the maximum (approximately 91.6 percent) in 5 to 7 days. The number of transverse arteries and the number of vessels greater than 0.1 mm in diameter on the 3-day delay duration and the 6-day delay duration were significantly greater than those of the normal group. The number of transverse arteries and the number of vessels greater than 0.1 mm in diameter on the 6-day inhibition duration were not significantly changed compared with the normal group. Microvascular density on the 6-day delay duration obviously increased, whereas the 6-day inhibition duration was not significantly changed in comparison to the normal group. CONCLUSION: Endogenous VEGF is an initiating factor of the surgical delay effect by controlling choke vessel dilation and neovascularization within the choke zones.