Hypoxia improves hair inductivity of dermal papilla cells via nuclear NADPH oxidase 4-mediated reactive oxygen species generation'.

BACKGROUND: Dermal papilla cells (DPCs) play a key role in hair regeneration and morphogenesis. Therefore, tremendous efforts have been made to promote DPC hair inductivity. OBJECTIVES: The aim of this study was to investigate the mitogenic and hair inductive effects of hypoxia on DPCs and examine the underlying mechanism of hypoxia-induced stimulation of DPCs. METHODS: DPCs' hair inductivity was examined under normoxia (20% O2 ) and hypoxia (2% O2 ). RESULTS: Hypoxia significantly increased the proliferation and delayed senescence of DPCs via Akt phosphorylation and downstream pathways. Hypoxia upregulated growth factor secretion of DPCs through the mitogen-activated protein kinase pathway. Hypoxia-preconditioned DPCs induced the telogen-to-anagen transition in C3 H mice, and also enhanced hair neogenesis in a hair reconstitution assay. Injected green fluorescent protein-labelled DPCs migrated to the outer root sheath of the hair follicle, and hypoxia-preconditioning increased survival and migration of DPCs in vivo. Conditioned medium obtained from hypoxia increased the hair length of mouse vibrissa follicles via upregulation of alkaline phosphatase, vascular endothelial growth factor, and glial cell line-derived neurotrophic factor. We examined the mechanism of this hypoxia-induced stimulation, and found that reactive oxygen species (ROS) play a key role. For example, inhibition of ROS generation by N-acetylcysteine or diphenyleneiodonium treatment attenuated DPCs' hypoxia-induced stimulation, but treatment with ROS donors induced mitogenic effects and anagen transition. NADPH oxidase 4 is highly expressed in the DPC nuclear region, and NOX4 knockout by CRISPR-Cas9 attenuated the hypoxia-induced stimulation of DPCs. CONCLUSIONS: Our results suggest that DPC culture under hypoxia has great advantages over normoxia, and is a novel solution for producing DPCs for cell therapy. What's already known about this topic? Dermal papilla cells (DPCs) play a key role in hair regeneration and morphogenesis, but they are difficult to isolate and expand for use in cell therapy. Tremendous efforts have been made to increase proliferation of DPCs and promote their hair formation ability. What does this study add? Hypoxia (2% O2 ) culture of DPCs increases proliferation, delays senescence and enhances hair inductivity of DPCs. Reactive oxygen species play a key role in hypoxia-induced stimulation of DPC. What is the translational message? Preconditioning DPCs under hypoxia improves their hair regenerative potential, and is a novel solution for producing DPCs for cell therapy to treat hair loss.

Antimicrobial activities of an oxygenated cyclohexanone derivative isolated from Amphirosellinia nigrospora JS-1675 against various plant pathogenic bacteria and fungi.

AIMS: To evaluate the antimicrobial activities of an active compound isolated from the culture broth of Amphirosellinia nigrospora JS-1675 against various plant pathogenic bacteria and fungi. METHODS AND RESULTS: While screening for bioactive secondary metabolites from endophytic fungi, we found that A. nigrospora JS-1675 showed strong in vitro antibacterial activity against Ralstonia solanacearum. One compound (1) was isolated and identified as (4S, 5S, 6S)-5,6-epoxy-4-hydroxy-3-methoxy-5-methyl-cyclohex-2-en-1-one. Growth of most of the tested phytopathogenic bacteria was inhibited by compound 1 and the ethyl acetate (EtOAc) layer except Pseudomonas syringae pv. lachrymans. Compound 1 also inhibited the mycelial growth of several plant pathogenic fungi. Both compound 1 and the EtOAc layer reduced bacterial leaf spot disease in detached peach leaves. They also suppressed the development of bacterial wilt on tomato seedlings quite effectively. CONCLUSIONS: Amphirosellinia nigrospora JS-1675 showed antimicrobial activity against plant pathogenic bacteria and fungi by producing compound 1. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report on the occurrence of compound 1 in A. nigrospora JS-1675 and its efficacy against plant pathogenic bacteria and fungi. Their strong disease control efficacy against tomato bacterial wilt suggests that this fungus can be used as a microbial bactericide.

Antibacterial activities of penicillic acid isolated from Aspergillus persii against various plant pathogenic bacteria.

UNLABELLED: The emergence of pathogenic bacterial strains resistant to agrochemicals and the increasing demand for organic foods have led to the discovery of new antibacterial metabolites that can be used either directly or as a lead molecule for development of synthetic bactericides. During the screening of antibacterial fungal cultures, we found that one fungal strain, Aspergillus persii EML-HPB1-11, showed strong in vitro antibacterial activity against Xanthomonas arboricola pv. pruni (Xap) with a minimum inhibitory concentration (MIC) of 10% of fermentation broth filtrate. The active compound was identified as penicillic acid (PA: 3-methoxy-5-methyl-4-oxo-2,5-hexadienoic acid) by mass and NMR spectroscopy. The in vitro antibacterial activity of PA was tested against 12 phytopathogenic bacteria. All of the bacterial pathogens tested were highly inhibited by PA with MIC values of 12·3-111·1 µg ml(-1) . It also effectively suppressed the development of bacterial spot disease in detached peach leaves, showing control values of 82·4 and 94·1% at concentrations of 111·1 and 333·3 µg ml(-1) respectively. This is the first report on the production of PA by A. persii. This study suggests that PA can be used as a lead molecule for development of synthetic bactericides for control of various plant diseases. SIGNIFICANCE AND IMPACT OF THE STUDY: Penicillic acid (PA) produced by the seed-borne fungus Aspergillus persii EML-HPB1-11 showed antibacterial activity against various plant pathogenic bacteria. The compound effectively inhibited the growth of 12 plant pathogenic bacteria and successfully controlled bacterial spot disease on peach leaf. These results suggest that PA can be used as a lead molecule for development of synthetic agrochemicals to control plant bacterial diseases.

Effects of honeybee venom supplementation in drinking water on growth performance of broiler chickens.

The effects of water supplementation of bee venom (BV) on performance, antioxidant activity, and liver function in Arbor Acres broiler chickens were investigated. Hence, 3 experimental treatment groups (control, 0.5 mg/L of BV, and 1 mg/L of BV) were allocated to 3 replicates of 5,000 one-day-old chicks each. The control group was kept on tap water, whereas the other 2 groups were supplied water supplemented with 0.5 and 1 mg of BV, respectively, per liter of drinking water. Broilers were provided ad libitum access to feed for the experimental period of 1 to 28 d of age. Supplementing drinking water with BV significantly increased BW gain at 28 d of age (P < 0.05). The average daily weight gain from d 1 to 28 was increased for birds supplemented with BV compared with control birds. The increase in BW gain was more pronounced with supplementation of 1 mg/L of BV compared with 0.5 mg/L of BV. An improved feed intake was noted in groups supplemented with BV as compared with control chicks. Liver function enzymes, aspartate aminotransferase, and alanine aminotransferase activities including total cholesterol, total protein, albumin, and globulin were not changed by BV supplementation. Tap water supplementation of BV did not alter the number of leukocytes, erythrocytes, heterophils, and lymphocytes. However, the antioxidative activities estimated as a superoxide dismutase-like activity of broiler chicks supplemented with BV was significantly increased (P < 0.05) in comparison with those without BV supplementation. These data indicate a possibility of better broiler performance through BV supplementation under conditions of severe stressful challenges the newly born chicks encounter.

Renal failure and progressive pancytopenia.

Hyperparathyroidism may be a precipitating factor to the development of myelofibrosis; however, this is extremely rare with only a few documented case reports of myelofibrosis caused by secondary hyperparathyroidism. We describe a case of a 24-year-old female who had a failed live donor renal transplant and secondary hyperparathyroidism. While on haemodialysis she became increasingly pancytopenic despite erythropoietin injections and adequate iron, vitamin B12 and folate replacement. Her secondary hyperparathyroidism evolved to tertiary hyperparathyroidism despite vitamin D supplementation and phosphate binders. In order to determine the cause of her pancytopenia, a bone marrow biopsy was performed that confirmed myelofibrosis due to her secondary hyperparathyroidism. Following a successful parathyroidectomy in a tertiary hospital, her pancytopenia resolved and she is now awaiting a second transplant.

Synthesis and antimicrobial activity of novel 3-[(aminopyrimidiniumyl)thio]methyl cephalosporins.

A series of novel cephalosporin compounds which have 3-[(aminopyrimidiniumyl)thio]methyl substituents was synthesized. They show high antimicrobial activity against various bacterial species including Pseudomonas aeruginosa. Structure-activity relationships with various thiopyrimidines, thiopyrimidiniums, bicyclic thiotriazolopyrimidiniums, and bicyclic thioimidazolopyrimidiniums as 3'-substituents were also studied; cephalosporins with quarternized pyrimidinium moieties have better antimicrobial activities than neuteral pyrimidine cephalosporins, and stabilization of the positive charge on the pyrimidinium moieties is essential for better activity. According to semiempirical PM3 calculations, amino and alkylthio substituents on the pyrimidinium rings play a major role in charge stabilization and delocalization.

Oral colchicine for the treatment of experimental traction retinal detachment.

In proliferative vitreoretinopathy and trauma, long-term reattachment of the retina is often prevented by the formation of contractile cellular membranes on the retinal surface and within the vitreous cavity. Colchicine, a well-documented inhibitor of microtubule assembly, is a potent inhibitor of retinal pigment epithelium cell, astrocyte, and fibroblast proliferation and migration. To study the therapeutic value of orally administered colchicine, we used an experimental animal model in which intravitreally injected platelet-derived growth factor and fibronectin produced traction retinal detachments in rabbits. With oral administration of colchicine, we were able to decrease the incidence and severity of traction retinal detachment from 74% in controls (20 of 27 eyes) to 29.6% in the treated animals (eight of 27 eyes) at five weeks (P less than .0009). These results, and the apparent lack of retinal and systemic toxicity, suggest that oral therapy with colchicine may prove to be of value in the treatment of human disease.

Extension of retinal detachments as a complication of pneumatic retinopexy.

Pneumatic retinopexy is a promising new alternative technique to scleral buckling for the treatment of selected cases of retinal detachment. We describe two cases, however, in which intravitreal gas injection caused further extension of the retinal detachment that in one case led to new macular detachment. This complication of pneumatic retinopexy has not been reported before, to our knowledge, and it may represent a significant limitation to the technique.

Intravitreous fibronectin and platelet-derived growth factor. New model for traction retinal detachment.

In proliferative vitreoretinopathy and trauma, traction retinal detachments result from cellular migration into the vitreous cavity with contractile membrane formation. Cleary and Ryan have established the efficacy of intravitreous injection of autologous blood in reproducing this pathologic process in the rabbit eye. It has previously been shown that two serum components, fibronectin and platelet-derived growth factor, stimulate cellular migration. We now show that contractile membranes and traction retinal detachments occur in 72% of rabbit eyes within three weeks following intravitreous injection of fibronectin and platelet-derived growth factor. These results provide a straightforward new model to study the development of intravitreous cellular membranes and traction retinal detachments.

The rate of sulfur hexafluoride escape from a plastic syringe.

Sulfur hexafluoride (SF6) gas is widely used for internal tamponade during retinal reattachment surgery and is commonly injected into the eye from a 10-mL plastic syringe. The rate of diffusion of SF6 out of a plastic syringe has not bee studied. We measured the percentage of SF6 gas in a 10-mL plastic syringe by gas chromatography, confirmed by infrared spectrometry. Measurements were obtained immediately after aspiration, and at 30 s and 10, 15, 60, 90, and 120 minutes, and 18 hours. A marked decrease in SF6 concentration, from 97% at 30 s to 76% at 60 minutes and 2% at 18 hours, was noted. The results were highly reproducible. Sulfur hexafluoride gas should be injected into the patient's eye as soon as possible after aspiration from the tank to ensure accurate concentrations.

Interphotoreceptor retinoid-binding protein levels in subretinal fluid from rhegmatogenous retinal detachment and retinopathy of prematurity.

Interphotoreceptor retinoid-binding protein (IRBP) has been detected qualitatively in subretinal fluid associated with rhegmatogenous retinal detachments. We have used a quantitative enzyme-linked immunosorbent assay to determine the IRBP concentrations in 24 fluid specimens collected at retinal reattachment surgery from 22 patients, and from 17 patients who underwent surgery for retinopathy of prematurity with traction detachment. We observed a wide range of concentrations (1 to 176 micrograms of IRBP per milligram of protein). Higher concentrations were found only in fluid from the more recent rhegmatogenous detachments. The lowest concentrations were detected among fluids drained from under rhegmatogenous detachments ranging from five days' to one year's duration. The IRBP concentration in subretinal fluid showed no correlation with visual outcome and may be influenced by IRBP turnover in the vitreous cavity. Most strikingly, none of the 17 samples from patients with retinopathy of prematurity contained detectable amounts of IRBP.

Combined clinical and computed tomographic diagnosis of orbital lymphoid tumors.

Computed tomography has made it possible to make a strongly presumptive preoperative diagnosis of orbital lymphoid tumors, particularly when the radiographic findings are analyzed in conjunction with the clinical features. Twenty-six patients (with 27 orbital lymphoid tumors) had an average age of 57 years and had painless swelling or low-grade proptosis averaging 7.5 months in duration. The computed tomographic findings were highly characteristic. Almost all of the tumors had a retrobulbar or superior orbital component. In both the coronal and axial planes, distinctive growth patterns and contourings were discovered. The lesions molded themselves to preexisting orbital structures without eroding bone or enlarging the orbit. Against the bone, globe, and muscle edges, the lesions featured smooth, sharply demarcated contours with abruptly acute or perpendicular angulations, whereas a streaky profile became apparent as they irregularly infiltrated the retrobulbar fat, reflecting involvement of microfascial structural elements. No distinguishing differences were discovered in the growth patterns of the benign and the malignant tumors.

Combined clinical and computed tomographic diagnosis of primary lacrimal fossa lesions.

We studied 39 patients who had solid mass-lesions primary in the lacrimal gland by computed tomography and reviewed their clinical histories. Twenty-three patients had either inflammatory conditions (16 cases) or lymphoid tumors (seven cases), with average symptomatic periods of less than a year. In this group, soft-tissue contour analysis in the axial and corneal projections demonstrated diffuse, compressed, and molded enlargements of the lacrimal gland in an oblong fashion, and there were no associated bone defects. Sixteen parenchymal benign or malignant tumors (six benign mixed tumors, one schwannoma, and nine malignant epithelial tumors) exhibited rounded or globular soft-tissue outlines and were frequently associated with contiguous bone changes. The benign tumors had smooth encapsulated outlines at their margins, whereas the malignant tumors displayed microserrations indicative of infiltration. The patients with the benign mixed tumors had had symptoms, on the average, for more than a year, whereas those with epithelial malignancies became symptomatic or had a preexisting benign mixed tumor that became exacerbated in periods of less than six months. Contour analysis of the soft-tissue mass depicted in coronal and axial tomograms is a valuable adjunct that leads to more accurate preoperative diagnosis when combined with a radiographic search for bone changes and the clinical history. Once a diagnosis regarding the presumptive lesional family has been made preoperatively, corticosteroid therapy may be instituted for acute inflammation and biopsies through the eyelid should be performed for suspected chronic inflammations, lymphoid lesions, or epithelial malignancies. A lateral orbitotomy without prior biopsy should be performed for rounded, well-encapsulated masses of long duration that are likely to be benign mixed tumors.

Computational modelling of blood flow through curved stenosed arteries.

A computational model of three-dimensional blood flow in curved arteries with elliptic stenosis was developed. Two groups of models, (a) different angles of curvature and (b) degrees of stenosis, have been studied under typical conditions for stenosed coronary artery. Useful information on the haemodynamics has been obtained. Results of pressure drop show that the presence of the curvature augments the increased flow resistance due to stenotic lesions. The study also demonstrates the significant presence of secondary flow in a curved artery. In addition, the results have shown that the secondary flow in a curved artery brings about elevated shear stress on the vessel wall. These results indicated that both curvature and stenosis should be considered together by cardiologists to assess or quantify the severity of the stenosis. This study employed a powerful computer-aided design (CAD) package to construct the model and a commercial computational fluid dynamics (CFD) code for the analysis of blood flow in stenosed arteries. The long-term application of this form of research promises to be an effective tool for gaining insights into the pathology of arterial diseases.

Contrast echocardiography to assess left ventricular volume and function in Beagle dogs: comparison with 3-Tesla dual source parallel cardiac magnetic resonance imaging.

This study was performed to evaluate the effect and feasibility of contrast echocardiography (CE) compared with unenhanced echocardiography (UE) and cardiac magnetic resonance imaging (CMRI) to assess left ventricular (LV) volume and function, including end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) in six healthy Beagles. When the dogs were conscious, LV measurements using CE were significantly higher than those obtained using UE, except for EF, and were similar to the values obtained using CMRI. Additionally, EDV, SV, and EF obtained using UE from anesthetized dogs were significantly lower than those obtained using CE or CMRI. Measurements of EDV, SV and EF using CE were not significantly different from the corresponding measurements obtained using CMRI (31.13±2.18 vs. 32.88±1.17 mL, 18.41±1.25 vs. 17.92±0.96 mL, 59.29±2.29% vs. 53.33±1.69%, respectively). Inter-observer agreements for UE (0.74±0.05) were lower than those for CE (0.80±0.04) and CMRI (0.92±0.03). In conclusion, LV function was assessed reproducibly using CE, and the measurements obtained were consistent with reference standard measurements obtained using CMRI. Measurements made using CE agreed more closely with CMRI than those made using UE.

Preoperative laser photocoagulation to mark tiny retinal breaks in eyes with retinal detachment.

We used preoperative argon laser photocoagulation to create a white intraretinal color change to mark the location of a tiny retinal break in an aphakic eye with rhegmatogenous retinal detachment. The break was visible only by fundus biomicroscopy with a three-mirror contact lens and could not be seen by indirect ophthalmoscopy. Intraretinal uptake of laser energy is accomplished with a small spot size and moderate energy levels. This technique facilitates rapid intraoperative identification and localization of small retinal breaks that are otherwise difficult to visualize.

Silicone oil in the treatment of complicated retinal detachments.

Silicone oil is now used with increasing frequency to treat cases of complicated retinal detachment (RD). The authors report their results using silicone oil in eyes with RD resulting from proliferative diabetic retinopathy (PDR) or proliferative vitreoretinopathy (PVR). The retina was completely reattached at last examination in 16 (70%) of 23 eyes with PDR and 20 (67%) of 30 eyes with PVR. Final vision of 5/200 or better was obtained in 5 eyes with PDR (22%) and 16 eyes with PVR (53%) (P = 0.0016). Reproliferation of epiretinal membranes occurred in 26% of diabetics and 23% of eyes with PVR. Silicone oil did not cause regression of iris neovascularization. Complications of silicone oil included corneal decompensation, lens opacification, intraocular pressure elevation, and hypotony.