Comparative efficacy evaluation of disinfectants against severe acute respiratory syndrome coronavirus-2.

BACKGROUND: Disinfection is one of the most effective ways to block the rapid transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Due to the prolonged coronavirus disease 2019 (COVID-19) pandemic, disinfectants have become crucial to prevent person-to-person transmission and decontaminate hands, clothes, facilities and equipment. However, there is a lack of accurate information on the virucidal activity of commercial disinfectants. AIM: To evaluate the virucidal efficacy of 72 commercially available disinfectants constituting 16 types of ingredients against SARS-CoV-2. METHODS: SARS-CoV-2 was tested with various concentrations of disinfectants at indicated exposure time points as recommended by the manufacturers. The 50% tissue culture infectious dose assay was used to calculate virus titre, and trypan blue staining and CCK-8 were used to assess cell viability after 3-5 days of SARS-CoV-2 infection. FINDINGS: This study found that disinfectants based on 83% ethanol, 60% propanol/ethanol, 0.00108-0.0011% sodium dichloroisocyanurate and 0.497% potassium peroxymonosulfate inactivated SARS-CoV-2 effectively and safely. Although disinfectants based on 0.05-0.4% benzalkonium chloride (BAC), 0.02-0.07% quaternary ammonium compound (QAC; 1:1), 0.4% BAC/didecyldimethylammonium chloride (DDAC), 0.28% benzethonium chloride concentrate/2-propanol, 0.0205-0.14% DDAC/polyhexamethylene biguanide hydrochloride (PHMB) and 0.5% hydrogen peroxide inactivated SARS-CoV-2 effectively, they exhibited cytotoxicity. Conversely, disinfectants based on 0.04-4% QAC (2:3), 0.00625% BAC/DDAC/PHMB, and 0.0205-0.14% and 0.0173% peracetic acid showed approximately 50% virucidal efficacy with no cytotoxicity. Citric acid (0.4%) did not inactivate SARS-CoV-2. CONCLUSION: These results indicate that most commercially available disinfectants exert a disinfectant effect against SARS-CoV-2. However, re-evaluation of the effective concentration and exposure time of certain disinfectants is needed, especially citric acid and peracetic acid.

[Analysis of PROKR2 gene mutation in patients with hypogonadotropic hypogonadism].

To investigate the clinical and genetic characteristics of patients with idiopathic hypogonadotropic hypogonadism (IHH), the clinical data of 23 patients with IHH were retrospectively analyzed. Gene analyses were accomplished with whole-exome sequencing (WES) and Sanger sequencing. Functional prediction of mutation sites was conducted using two bioinformatics platforms, SIFT and Polyphen. Among the 23 patients with IHH, 9 patients carried prokinin 2 (PROKR2) gene mutations including 4 missense mutations (p.W178S, p.Y113H, p.A103V, p.R164Q), and 1 frameshift mutation (p.D42delinsDED), the remaining 14 cases were found negative in gene sequencing. Functional prediction showed that the above mutations may affect protein function suggestive of a pathogenic role of PROKR2 mutation in the patients. There were no significant differences in the levels of follicle-stimulating hormone, luteinizing hormone, testosterone, and estradiol between the IHH patients with PROKR2 gene mutation and those without. PROKR2 gene mutation might associated with IHH, and the mutations reported in the present study could enrich the pathogenic spectrum of genes.

Safety and Efficacy of Stent-Assisted Coiling of Unruptured Intracranial Aneurysms Using Low-Profile Stents in Small Parent Arteries.

BACKGROUND AND PURPOSE: Stent-assisted coiling of intracranial aneurysms arising from small vessels (≤ 2.0 mm) is a common procedure. However, data regarding its treatment outcomes are scarce. This study evaluated the clinical and radiologic outcomes of stent-assisted coiling using low-profile stents for aneurysms of small parent arteries. MATERIALS AND METHODS: From November 2015 to October 2020, sixty-four patients with 66 aneurysms arising from parent arteries of ≤2.0 mm were treated with stent-assisted coiling using a Low-Profile Visualized Intraluminal Support Junior (LVIS Jr) or the Neuroform Atlas stent in a single institution. The clinical and radiologic data were retrospectively reviewed, and the risk factors for procedure-related complications were evaluated. RESULTS: The LVIS Jr and Neuroform Atlas stents were used in 22 (33.3%) and 44 (66.7%) cases, respectively. Technical success was achieved in 66 cases (100%). Immediate postprocedural aneurysm occlusion grades assessed by the Raymond-Roy occlusion classification were I (57.6%), II (19.7%), and III (22.7%), respectively. Procedure-related complications occurred in 10 cases (15.2%), with 8 thromboembolic complications (12.1%) and 2 hemorrhagic complications (3.0%). Procedure-related morbidity was 4.5% without mortality. On multivariate analysis, current smoking (odds ratio = 7.1, P = .021) had a statistically significant effect on procedure-related complications. CONCLUSIONS: Stent-assisted coiling of intracranial aneurysms with low-profile stents in small vessels (≤ 2.0 mm) had a 100% success rate and a 15.2% overall complication rate with 4.5% morbidity. Current smoking was a significant risk factor associated with procedure-related complications.

Lactate augments intramuscular triglyceride accumulation and mitochondrial biogenesis in rats.

Regular exercise induces intramuscular triglyceride accumulation with improved mitochondrial ability, but the mechanism remains unknown. The glycolytic product of exercise, lactate, has long been rec-ognized to suppress lipolysis and promote lipogenesis in adipocytes through inhibition of the cAMP-PKA pathway by activation of the G protein-coupled receptor (GPR81). However, whether lactate results in a similar process in skeletal muscle is unclear. Here, by using intramuscular injection of lactate to the gastrocnemius, the lipid metabolism effects were investigated in rat skeletal muscle. Firstly, the lactate-injection effect was verified by comparing changes in blood lactate levels from injection and exercise (30 min, 31 m/min, treadmill running). After five weeks of lactate intervention, intramuscular triglyceride levels in the gastrocnemius and the proportion of epididymis adipose mass to body weight increased. Chronic intramuscular injection of lactate elevated lactate receptor, GPR81, and reduced cAMP response element-binding (CREB) and P-CREB abundance in the gastrocnemius. Additionally, there was a significant decline in lipolytic-related proteins (AMPK, P-AMPK, P-HSL, CPT-1B, TGF-ß2, SDHA) and a significant increase in fat synthesis proteins (SREBP-1C, PPAR-γ). Surprisingly, mitochondrial biomarkers (PGC-1α, CS) were also increased in the gastrocnemius, suggesting that chronic lactate might promote mitochondria biogenesis. Together, these results demonstrated that lactate may play a crucial role in triglyceride storage and mitochondria biogenesis in the skeletal muscle of rat.

Intramedullary pneumorrhachis following a cervical epidural steroid injection.

Pneumorrhachis (PR) is a rare radiological condition characterized by the presence of intraspinal air. PR is commonly classified as spontaneous (nontraumatic), traumatic, or iatrogenic, and iatrogenic PR is the most common and often occurs secondary to invasive procedures such as epidural anesthesia, lumbar puncture, or spinal surgery. PR is usually asymptomatic, but it can produce symptoms associated with its underlying pathology. Here, we report a rare case of intramedullary cervical PR following a cervical epidural steroid injection (ESI) and include pertinent discussion.

[Genetic Polymorphisms of 17 Y-STR Loci in Nantong Han Population].

OBJECTIVES: To analyze the genetic phenotypes of Nantong Han population and evaluate the application value of 17 Y-STR loci in Nantong population. METHODS: The peripheral blood samples were collected from 343 unrelated Nantong Han males and the genomic DNA were extracted by Chelex-100 method. Genotyping was performed using the AmpFℓSTR Yfiler™ Kit. The results were compared with other 12 Han populations, including Anhui, Jiangsu, Jiangxi, Shandong, Shanghai, Zhejiang （1）, Lanzhou, Nanyang, Luzhou, Mudanjiang, Shanxi and Zhejiang （2）, and 9 minority populations （Mongol, Xibe, Tibetan in Lhasa, Tibetan in Qinghai, Kazak, Uighur, Manchu, Paiwan in Taiwan and Tujia）. RESULTS: A total of 327 different haplotypes were found in 17 Y-STR loci in Nantong Han population. The haplotype diversity （HD） was 0.999 7. The Rst value between Nantong Han and other Chinese populations ranged from -0.000 6 to 0.263 5. The multidimensional scaling results showed that Nantong Han population had no significant differences between most of the Han populations, but had significant differences between most of Chinese minority populations. CONCLUSIONS: Seventeen Y-STR loci can be a powerful tool for forensic application because of its high polymorphism in Nantong Han population.

CRAF gene fusions in pediatric low-grade gliomas define a distinct drug response based on dimerization profiles.

Pediatric low-grade gliomas (PLGGs) are commonly associated with BRAF gene fusions that aberrantly activate the mitogen-activated protein kinase (MAPK) signaling pathway. This has led to PLGG clinical trials utilizing RAF- and MAPK pathway-targeted therapeutics. Whole-genome profiling of PLGGs has also identified rare gene fusions involving another RAF isoform, CRAF/RAF1, in PLGGs and cancers occuring in adults. Whereas BRAF fusions primarily dysregulate MAPK signaling, the CRAF fusions QKI-RAF1 and SRGAP3-RAF1 aberrantly activate both the MAPK and phosphoinositide-3 kinase/mammalian target of rapamycin (PI3K/mTOR) signaling pathways. Although ATP-competitive, first-generation RAF inhibitors (vemurafenib/PLX4720, RAFi) cause paradoxical activation of the MAPK pathway in BRAF-fusion tumors, inhibition can be achieved with 'paradox breaker' RAFi, such as PLX8394. Here we report that, unlike BRAF fusions, CRAF fusions are unresponsive to both generations of RAFi, vemurafenib and PLX8394, highlighting a distinct responsiveness of CRAF fusions to clinically relevant RAFi. Whereas PLX8394 decreased BRAF-fusion dimerization, CRAF-fusion dimerization is unaffected primarily because of robust protein-protein interactions mediated by the N-terminal non-kinase fusion partner, such as QKI. The pan-RAF dimer inhibitor, LY3009120, could suppress CRAF-fusion oncogenicity by inhibiting dimer-mediated signaling. In addition, as CRAF fusions activate both the MAPK and PI3K/mTOR signaling pathways, we identify combinatorial inhibition of the MAPK/mTOR pathway as a potential therapeutic strategy for CRAF-fusion-driven tumors. Overall, we define a mechanistic distinction between PLGG-associated BRAF- and CRAF/RAF1 fusions in response to RAFi, highlighting the importance of molecularly classifying PLGG patients for targeted therapy. Furthermore, our study uncovers an important contribution of the non-kinase fusion partner to oncogenesis and potential therapeutic strategies against PLGG-associated CRAF fusions and possibly pan-cancer CRAF fusions.

Role of HSPA1L as a cellular prion protein stabilizer in tumor progression via HIF-1α/GP78 axis.

The cellular prion protein (PrPC) is associated with metastasis, tumor progression and recurrence; however, the precise mechanisms underlying its action is not well understood. Our study found that PrPC degradation decreased tumor progression in colorectal cancer (CRC). In a CRC cell line and human CRC tissue exposed to hypoxia, induced heat-shock 70-kDa protein-1-like (HSPA1L) expression stabilized hypoxia-inducible factor-1α (HIF-1α) protein and promoted PrPC accumulation and tumorigenicity in vivo. PrPC was degraded via the proteasome pathway mediated by the ubiquitin-protein E3 ligase glycoprotein 78 (GP78), which interacts directly with PrPC. However, hypoxia-induced HSPA1L interacted with GP78 and inhibited its functions. HSPA1L knockdown facilitated the interaction of GP78 and PrPC, thereby increasing PrPC ubiquitination. Thus, GP78 was identified as the ubiquitinase for PrPC, thereby revealing an essential mechanism that controls PrPC levels in CRC. Our results suggest that the HSPA1L/HIF-1α/GP78 axis has a crucial role in PrPC accumulation during tumor progression.

Value of macrobiopsies and transanal endoscopic microsurgery in the histological work-up of rectal neoplasms: A retrospective study.

AIM: To evaluate a step up approach: Taking macrobiopsies and performing excision biopsies in patients with suspected rectal cancer in which biopsies taken though the flexible endoscope showed benign histology. METHODS: Patients with a rectal neoplasm who underwent flexible endoscopy and biopsies were included. In case of benign biopsies rigid rectoscopy and macrobiopsies were employed. If this failed to prove malignancy, transanal endoscopic microsurgery (TEM) was used in a final effort to establish a certain preoperative diagnosis. The preoperative results were compared with the findings after surgical excision and follow up to calculate the reliability of this algorithm. RESULTS: One hundred and thirty-two patients were included. One hundred and ten patients with a carcinoma and 22 with an adenoma. Seventy-five of 110 carcinomas were proven malignant after flexible endoscopy. With the addition of rigid endoscopy and taking of macrobiopsies, this number increased to 89. Performing TEM excision biopsies further enlarged the number of proven malignancies to 100. CONCLUSION: The step-up approach includes taking macrobiopsies through the rigid rectoscope and performing excision biopsies using transanal endoscopic microsurgery in addition to flexible endoscopy. This approach, reduced the number of missed preoperative malignant diagnoses from 32% to 9%.

Novel coronaviruses, astroviruses, adenoviruses and circoviruses in insectivorous bats from northern China.

Bats are considered as the reservoirs of several emerging infectious disease, and novel viruses are continually found in bats all around the world. Studies conducted in southern China found that bats carried a variety of viruses. However, few studies have been conducted on bats in northern China, which harbours a diversity of endemic insectivorous bats. It is important to understand the prevalence and diversity of viruses circulating in bats in northern China. In this study, a total of 145 insectivorous bats representing six species were collected from northern China and screened with degenerate primers for viruses belonging to six families, including coronaviruses, astroviruses, hantaviruses, paramyxoviruses, adenoviruses and circoviruses. Our study found that four of the viruses screened for were positive and the overall detection rates for astroviruses, coronaviruses, adenoviruses and circoviruses in bats were 21.4%, 15.9%, 20% and 37.2%, respectively. In addition, we found that bats in northern China harboured a diversity of novel viruses. Common Serotine (Eptesicus serotinu), Fringed long-footed Myotis (Myotis fimriatus) and Peking Myotis (Myotis pequinius) were investigated in China for the first time. Our study provided new information on the ecology and phylogeny of bat-borne viruses.

Outbreak of hirame rhabdovirus infection in cultured spotted sea bass Lateolabrax maculatus on the western coast of Korea.

In this study, we determined the cause of a disease outbreak in spotted sea bass, Lateolabrax maculatus reared in culture cages on the western coast of Korea in 2013. The major signs in the diseased fish exhibited were haemorrhaging on the membranes of the abdomen, gastrointestinal organs and opercular gills, as well as an enlarged spleen. No external morphological signs of infection were visible, except for a darkening in colour. No parasites or pathological bacteria were isolated from the diseased fish; however, epithelioma papulosum cyprini (EPC) cells inoculated with tissue homogenates from the diseased fish showed cytopathic effects (CPEs). Virus particles in the EPC cells were bullet-shaped, 185-225 nm long and 70-80 nm wide, characteristic of Rhabdoviridae. Polymerase chain reaction analyses of homogenized tissues from the diseased fish and supernatants of cell cultures with CPEs indicated specific, 553-bp-long fragments corresponding to the matrix protein gene of the hirame rhabdovirus (HIRRV). Phylogenetically, the HIRRV phosphoprotein gene of spotted sea bass was more closely related to phosphoproteins from Chinese and Polish HIRRV strains than from other Korean strains. To our knowledge, this is the first report of HIRRV infection in cultured spotted sea bass.

Glycerol-3-phosphate acyltransferase-1 upregulation by O-GlcNAcylation of Sp1 protects against hypoxia-induced mouse embryonic stem cell apoptosis via mTOR activation.

Oxygen signaling is critical for stem cell regulation, and oxidative stress-induced stem cell apoptosis decreases the efficiency of stem cell therapy. Hypoxia activates O-linked ß-N-acetyl glucosaminylation (O-GlcNAcylation) of stem cells, which contributes to regulation of cellular metabolism, as well as cell fate. Our study investigated the role of O-GlcNAcylation via glucosamine in the protection of hypoxia-induced apoptosis of mouse embryonic stem cells (mESCs). Hypoxia increased mESCs apoptosis in a time-dependent manner. Moreover, hypoxia also slightly increased the O-GlcNAc level. Glucosamine treatment further enhanced the O-GlcNAc level and prevented hypoxia-induced mESC apoptosis, which was suppressed by O-GlcNAc transferase inhibitors. In addition, hypoxia regulated several lipid metabolic enzymes, whereas glucosamine increased expression of glycerol-3-phosphate acyltransferase-1 (GPAT1), a lipid metabolic enzyme producing lysophosphatidic acid (LPA). In addition, glucosamine-increased O-GlcNAcylation of Sp1, which subsequently leads to Sp1 nuclear translocation and GPAT1 expression. Silencing of GPAT1 by gpat1 siRNA transfection reduced glucosamine-mediated anti-apoptosis in mESCs and reduced mammalian target of rapamycin (mTOR) phosphorylation. Indeed, LPA prevented mESCs from undergoing hypoxia-induced apoptosis and increased phosphorylation of mTOR and its substrates (S6K1 and 4EBP1). Moreover, mTOR inactivation by rapamycin (mTOR inhibitor) increased pro-apoptotic proteins expressions and mESC apoptosis. Furthermore, transplantation of non-targeting siRNA and glucosamine-treated mESCs increased cell survival and inhibited flap necrosis in mouse skin flap model. Conversely, silencing of GPAT1 expression reversed those glucosamine effects. In conclusion, enhancing O-GlcNAcylation of Sp1 by glucosamine stimulates GPAT1 expression, which leads to inhibition of hypoxia-induced mESC apoptosis via mTOR activation.

[Analysis of BPPV in patients with bone mineral density results].

Objective:Analyze BPPV in patients with ultrasonic bone mineral density to investigate the relationship between the BPPV and bone density. Method:A total of 88 included subjects were selected from patients admitted to the Otolaryngological Department of Renhe Hospital, Beijing. Meanwhile, 76 healthy persons were included as control. The control group had similar age and gender distributions to the test group, and all healthy subjects had no history of vertigo in recent one year. Both groups underwent regular otolaryngological examinations, videonystagmography（VNG）,ultrasound bone densitometer test. According to gender, age, listening to group. Result:①Bone density of the test group was significantly lower than the control group（-2.010±1.658 vs 0.3605±0.875）,the difference was statistically significant（P<0.01）；②Incidence rates of bone mass loss（35 in 88,39.77%）and osteoporosis（26 in 88, 29.55%）bone mineral density decreased incidence of 69.32%, in the test group was significantly higher than that in the control group（bone mass loss, 13 in 76, 17.10%; osteoporosis 6 in 76,7.89%）, bone mineral density decreased incidence of 25.00%,the difference was statistically significant（P<0.01）；③The test group and control group according to different age groups, the test group all ages bone density T values significantly lower than the control group（P<0.01）,the difference was statistically significant. In the age groups, the incidence of bone loss was higher in the test group than that in the control group, the difference was statistically significant(P<0.01).④In the gender group, bone density of the test group women were significantly lower than the control group, the difference was statistically significant（P<0.05）； especially after the age of 60.⑤In the test group, 27 cases of bone mineral density is normal, with normal hearing 19 cases (70.37%), hearing loss 8 cases(29.63%);61 cases of bone loss, including normal hearing 48 cases (78.69%),hearing loss 13 cases (21.31%). The difference between hearing loss and bone loss had no statistical significance(P>0.05).⑥The logistic regression results showed that the prompt Higher bone mineral density T value was BPPV protection factors, OR=0.686,(P<0.01,95%CI: 1.32-5.85). Conclusion:BPPV in patients with bone mineral density value is lower than the normal control group, there is a higher incidence of bone loss, at the same time, along with the age increasing on the rise, especially women.

Role of peripheral sigma-1 receptors in ischaemic pain: Potential interactions with ASIC and P2X receptors.

BACKGROUND: The role of peripheral sigma-1 receptors (Sig-1Rs) in normal nociception and in pathologically induced pain conditions has not been thoroughly investigated. Since there is mounting evidence that Sig-1Rs modulate ischaemia-induced pathological conditions, we investigated the role of Sig-1Rs in ischaemia-induced mechanical allodynia (MA) and addressed their possible interaction with acid-sensing ion channels (ASICs) and P2X receptors at the ischaemic site. METHODS: We used a rodent model of hindlimb thrombus-induced ischaemic pain (TIIP) to investigate their role. Western blot was performed to observe changes in Sig-1R expression in peripheral nervous tissues. MA was measured after intraplantar (i.pl.) injections of antagonists for the Sig-1, ASIC and P2X receptors in TIIP rats or agonists of each receptor in naïve rats. RESULTS: Sig-1R expression significantly increased in skin, sciatic nerve and dorsal root ganglia at 3 days post-TIIP surgery. I.pl. injections of the Sig-1R antagonist, BD-1047 on post-operative days 0-3 significantly attenuated the development of MA during the induction phase, but had no effect on MA when given during the maintenance phase (days 3-6 post-surgery). BD-1047 synergistically increased amiloride (an ASICs blocker)- and TNP-ATP (a P2X antagonist)-induced analgesic effects in TIIP rats. In naïve rats, i.pl. injection of Sig-1R agonist PRE-084 alone did not produce MA; but it did induce MA when co-administered with either an acidic pH solution or a sub-effective dose of αßmeATP. CONCLUSION: Peripheral Sig-1Rs contribute to the induction of ischaemia-induced MA via facilitation of ASICs and P2X receptors. Thus, peripheral Sig-1Rs represent a novel therapeutic target for the treatment of ischaemic pain.

Disruption of effective connectivity from the dorsolateral prefrontal cortex to the orbitofrontal cortex by negative emotional distraction in obsessive-compulsive disorder.

BACKGROUND: Obsessive-compulsive disorder (OCD) has been associated with abnormal cognitive and emotional functions and these dysfunctions may be dependent on the disruption of dynamic interactions within neuronal circuits associated with emotion regulation. Although several studies have shown the aberrant cognitive-affective processing in OCD patients, little is known about how to characterize effective connectivity of the disrupted neural interactions. In the present study, we applied effective connectivity analysis using dynamic causal modeling to explore the disturbed neural interactions in OCD patients. METHOD: A total of 20 patients and 21 matched healthy controls performed a delayed-response working memory task under emotional or non-emotional distraction while undergoing functional magnetic resonance imaging. RESULTS: During the delay interval under negative emotional distraction, both groups showed similar patterns of activations in the amygdala. However, under negative emotional distraction, the dorsolateral prefrontal cortex (DLPFC) and the orbitofrontal cortex (OFC) exhibited significant differences between groups. Bayesian model averaging indicated that the connection from the DLPFC to the OFC was negatively modulated by negative emotional distraction in patients, when compared with healthy controls (p < 0.05, Bonferroni-corrected). CONCLUSIONS: Exaggerated recruitment of the DLPFC may induce the reduction of top-down prefrontal control input over the OFC, leading to abnormal cortico-cortical interaction. This disrupted cortico-cortical interaction under negative emotional distraction may be responsible for dysfunctions of cognitive and emotional processing in OCD patients and may be a component of the pathophysiology associated with OCD.

Vibrio vulnificus VvpE inhibits mucin 2 expression by hypermethylation via lipid raft-mediated ROS signaling in intestinal epithelial cells.

Mucin is an important physical barrier against enteric pathogens. VvpE is an elastase encoded by Gram-negative bacterium Vibrio vulnificus; however, the functional role of VvpE in intestinal mucin (Muc) production is yet to be elucidated. The recombinant protein (r) VvpE significantly reduced the level of Muc2 in human mucus-secreting HT29-MTX cells. The repression of Muc2 induced by rVvpE was highly susceptible to the knockdown of intelectin-1b (ITLN) and sequestration of cholesterol by methyl-ß-cyclodextrin. We found that rVvpE induces the recruitment of NADPH oxidase 2 and neutrophil cytosolic factor 1 into the membrane lipid rafts coupled with ITLN to facilitate the production of reactive oxygen species (ROS). The bacterial signaling of rVvpE through ROS production is uniquely mediated by the phosphorylation of ERK, which was downregulated by the silencing of the PKCδ. Moreover, rVvpE induced region-specific methylation in the Muc2 promoter to promote the transcriptional repression of Muc2. In two mouse models of V. vulnificus infection, the mutation of the vvpE gene from V. vulnificus exhibited an increased survival rate and maintained the level of Muc2 expression in intestine. These results demonstrate that VvpE inhibits Muc2 expression by hypermethylation via lipid raft-mediated ROS signaling in the intestinal epithelial cells.

Arachidonic acid promotes skin wound healing through induction of human MSC migration by MT3-MMP-mediated fibronectin degradation.

Arachidonic acid (AA) is largely released during injury, but it has not been fully studied yet how AA modulates wound repair with stem cells. Therefore, we investigated skin wound-healing effect of AA-stimulated human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) in vivo and its molecular mechanism in vitro. We found that transplantation of hUCB-MSCs pre-treated with AA enhanced wound filling, re-epithelization, and angiogenesis in a mouse skin excisional wound model. AA significantly promoted hUCB-MSCs migration after a 24 h incubation, which was inhibited by the knockdown of G-protein-coupled receptor 40 (GPR40). AA activated mammalian target of rapamycin complex 2 (mTORC2) and Aktser473 through the GPR40/phosphoinositide 3-kinase (PI3K) signaling, which was responsible for the stimulation of an atypical protein kinase C (PKC) isoform, PKCζ. Subsequently, AA stimulated phosphorylation of p38 MAPK and transcription factor Sp1, and induced membrane type 3-matrix metalloproteinase (MT3-MMP)-dependent fibronectin degradation in promoting hUCB-MSCs motility. Finally, the silencing of MT3-MMP in AA-stimulated hUCB-MSCs failed to promote the repair of skin wounds owing to impaired cell motility. In conclusion, AA enhances skin wound healing through induction of hUCB-MSCs motility by MT3-MMP-mediated fibronectin degradation, which relies on GPR40-dependent mTORC2 signaling pathways.

Potential synergistic effects of human placental extract and minoxidil on hair growth-promoting activity in C57BL/6J mice.

BACKGROUND: Human placenta extract (HPE) has been used to alleviate tiredness and promote wound healing, and for its antiageing functions; however, it has not yet been studied for its effects on hair growth. In the present study, we evaluated the in vitro effect of HPE on hair growth by observing its actions on human dermal papilla cells (DPCs). AIM: To define how HPE promotes induction of anagen hair growth during the telogen phase, and to understand the synergistic molecular mechanisms of HPE and minoxidil (MXD) actions on hair growth. METHODS: We examined the effects of HPE and MXD on C57BL6/J mice using haematoxylin and eosin staining, quantitative histomorphometry, hair growth scoring, immunohistochemistry and immunofluorescence on the dorsal skins of C57BL/6J mice. RESULTS: We found that HPE synergistically augmented the effects of MXD, a promoter of hair growth. In particular, histomorphometric analysis data indicated that subcutaneous injection of HPE induced an earlier anagen phase and prolonged the anagen phase. It also stimulated increases in both the number and size of hair follicles in groups treated with HPE alone and HPE + MXD. CONCLUSIONS: From our data, we conclude that HPE increases ß-catenin and Wnt3a expression levels. Overall, our findings suggest that HPE in combination with MXD has hair growth-promoting activity and is a potential novel therapeutic treatment for alopecia or baldness in humans.

Vibrio vulnificus VvhA induces NF-κB-dependent mitochondrial cell death via lipid raft-mediated ROS production in intestinal epithelial cells.

The Gram-negative bacterium Vibrio vulnificus produces hemolysin (VvhA), which induces cytotoxicity in mammalian cells. However, our understanding of the cytotoxic mechanism and the modes of action of VvhA are still fragmentary and incomplete. The recombinant protein (r) VvhA (50 pg/ml) significantly induces necrotic cell death and apoptosis in human intestinal epithelial (INT-407) cells. The apoptotic cell death induced by rVvhA is highly susceptible to the sequestration of cholesterol by methyl-ß-cyclodextrin, whereas for necrotic cell death, this shows a marginal effect. We found that rVvhA induces the aggregation of lipid raft components coupled with NADPH oxidase enzymes, in which rVvhA increased the interaction of NADPH oxidase 2 (NOX2, gp91(phox)) with a cytosolic protein NCF1 (p47(phox)) to facilitate the production of reactive oxygen species (ROS). rVvhA uniquely stimulated a conventional PKC isoform PKCα and induced the phosphorylation of both ERK and JNK, which are responsible for the activation of transcription factor NF-κB. rVvhA induced an NF-κB-dependent imbalance of the Bcl-2/Bax ratio, the release of mitochondrial cytochrome c, and caspase-3/-9 activation during its promotion of apoptotic cell death. In addition, rVvhA has the ability to inhibit the expression of cell cycle-related proteins, such as CDK2, CDK4, cyclin D1, and cyclin E. These results demonstrate that rVvhA induces NF-κB-dependent mitochondrial cell death via lipid raft-mediated ROS production by the distinct activation of PKCα and ERK/JNK in intestinal epithelial cells.

Lactoferrin causes IgA and IgG2b isotype switching through betaglycan binding and activation of canonical TGF-ß signaling.

Lactoferrin (LF), a pleiotropic iron-binding glycoprotein, is known to modulate the humoral immune response. However, its exact role in Ig synthesis has yet to be elucidated. In this study, we investigated the effect of LF on Ig production by mouse B cells and its underlying mechanisms. LF, like transforming growth factor (TGF)-ß1, stimulated B cells to produce IgA and IgG2b, while downregulating other isotypes. Using limiting dilution analysis, LF was shown to increase the frequency of IgA-secreting B-cell clones. This was paralleled by an increase in Ig germ-line α (GLα) transcripts, indicating that LF plays a role as an IgA switch factor. Interestingly, LF directly interacted with betaglycan (TGF-ß receptor III, TßRIII) and in turn induced phosphorylation of TßRI and Smad3 through formation of the TßRIII/TßRII/TßRI complex, leading to IgA isotype switching. Peroral administration of LF increased intestinal/serum IgA production as well as number of IgA plasma cells in lamina propria. Finally, we found that LF has an adjuvant activity when nontoxigenic Salmonella typhimurium was inoculated perorally, conferring protection against intragastrical infection of toxigenic S. typhimurium. These results suggest that LF has an important effect on the mucosal/systemic IgA response and can contribute to protection against intestinal pathogens.