High-yield strain of fusidic acid obtained by atmospheric and room temperature plasma mutagenesis and the transcriptional changes involved in improving its production in fungus Fusidium coccineum.

AIMS: To obtain the high-yield strain of fusidic acid, which is produced from fungus Fusidium coccineum and is the only fusidane-type antibiotic that has been used clinically, and confirm the changes in the transcription levels involved in increasing its production. METHODS AND RESULTS: By using the atmospheric and room temperature plasma mutagenesis technology, a high-yield mutant strain of fusidic acid-producing fungus F. coccineum was obtained. Using the genomic analysis of the original strain based on biosynthetic pathways of ergosterol and helvolic acid, we demonstrate that the pathway involved in the biosynthesis of 2,3-oxidosqualene from acetyl coenzyme A was shared by fusidic acid and ergosterol, and fusidic acid was finally synthesized by the catalysis of multiple cytochrome P450s and short-chain dehydrogenase/reductase from 2,3-oxidosqualene. Then, through the transcriptomic analysis of the original and mutagenized strain, it revealed that the proposed pathway from sucrose to fusidic acid was the most significantly up-regulated in the transcription levels of the mutant strain. CONCLUSIONS: The changes in the transcription levels of fusidic acid during its biosynthesis might result in high-yield of fusidic acid in the mutant strain. This is the first report on the whole biosynthetic pathway of fusidic acid in F. coccineum. SIGNIFICANCE AND IMPACT OF THE STUDY: This study obtain the genetic basis for the biosynthesis of fusidic acid which could be beneficial for the molecular modifications of F. coccineum to further increase its yield by fermentation in future, and established the foundation to reveal the mechanism of the high-yield of the mutant strain.

[Analysis on the imported Coronavirus Disease 2019 related cluster epidemic in rural areas of Chengdu].

An epidemiological investigation was carried out on a local cluster of outbreak caused by imported cases of Coronavirus Disease 2019 (COVID-19) in rural areas of Chengdu in December 2020, to find out the source of infection and the chain of transmission. According to Prevention and Control Protocol for COVID-19 (Version 7), field epidemiological investigation was adopted, combined with big data technology, video image investigation, gene sequencing and other methods to carry out investigation into COVID-19 cases and infections source tracing, analyze the epidemiological association, and map the chain of transmission. From December 7 to 17, 2020, 13 local COVID-19 confirmed cases and 1 asymptomatic case were diagnosed in Chengdu, of which 12 cases (85.71%) had a history of residence and activity in the village courtyard of Taiping (TP), Pidu (P) District, Chengdu. From November 8, 2020 to November 28, 2020, a group of inbound people form Nepal were transferred to the designated entry personnel quarantine hotel of P District which was adjacent to the TP village. During quarantine, there were 5 cases who tested positive for COVID-19. Through gene sequencing alignment, genes of local cases and Nepalese imported cases from the same period are homologous, all belong to the lineage of L2.2.3 (B.1.36 according to Pangolin lineage typing method). According to the results of field epidemiological investigation and gene sequencing analysis, the index case was most likely infected by contact with household waste of quarantine site. Under the situation of normalization prevention and control of COVID-19, sentinel monitoring of fever clinics in primary medical institutions is the key to early detection of the epidemic. The multi-department joint epidemiological investigation and the application of gene technology are the core links of the investigation and traceability of modern infectious diseases. The allocation of public health resources in rural areas needs to be strengthened. We need to improve the capacity for early surveillance and early warning of the epidemic in rural areas.

Identification and evaluation of outcome measurement instruments in pyoderma gangrenosum: a systematic review.

BACKGROUND: Pyoderma gangrenosum (PG) is a rare autoinflammatory skin condition that causes tissue destruction and subsequent painful ulcers. To date, there are no core domains or instruments for assessing PG severity in clinical trials, and current treatment paradigms rely on outcome measurements that have not been well characterized in the literature. OBJECTIVES: To perform two systematic reviews that (i) identify the outcome measurement instruments used in PG clinical trials and their corresponding domains and (ii) identify any associated validation studies and evaluate their measurement properties and methodological quality. METHODS: We systematically searched the MEDLINE and Embase databases for PG outcome measurement instruments. We also systematically searched for PG instrument validation studies. We evaluated the measurement properties and methodological quality of validation studies using the 2018 COSMIN Risk of Bias checklist. RESULTS: In total, seven clinical trials were included. These studies utilized a total of 20 different instruments, including 11 physician-reported instruments, eight patient-reported instruments and one composite instrument. Among these, 85% of the instruments lacked any validation data. Of the remaining three validated instruments (speed of healing, physician global assessment and resolution of inflammation), methodological quality was not available for half of the COSMIN categories. CONCLUSIONS: We identified 17 non-validated outcome measurement instruments used in PG clinical trials. We conclude that PG validation studies are required for existing instruments, and new instruments need to be developed to inform the consensus process for the development of a core outcome set for PG. What is already known about this topic? Pyoderma gangrenosum (PG) is a rare autoinflammatory skin condition that has been characterized by multiple outcome measurement instruments in clinical trials. However, there is no consensus on the most validated and appropriate outcome measurement instruments. What does this study add? This study identifies and evaluates 20 unique outcome measurement instruments for PG in the literature. Of these 20, 17 lack any instrument validation data, highlighting the need for future studies. What are the clinical implications of this work? Despite the current use of several outcome measurement instruments, future studies should explore the validation surrounding these instruments, as no instruments can currently be recommended.

Gentian violet for pyoderma gangrenosum: a retrospective chart review.

Pyoderma gangrenosum is a rare autoinflammatory skin disease. Treatment is multifactorial, addressing inflammation, pain, underlying disease, if present, and the wound. Gentian violet has been used for hundreds of years in a variety of dermatologic conditions for its anti-inflammatory properties. This study aims to evaluate gentian violet in wound healing for pyoderma gangrenosum. We conducted a retrospective chart review of patients with pyoderma gangrenosum treated with gentian violet at the Wake Forest School of Medicine Department of Dermatology in the last 10 years. The primary outcome was clinical improvement. Of the 34 cases that met inclusion criteria, 70% improved with gentian violet, 24% had no documented change, 3% initially improved then worsened, and 3% had unclear results. Gentian violet is a safe and cheap treatment that may improve resolution of pyoderma gangrenosum lesions in addition to systemic therapy.

The genetics of pyoderma gangrenosum and implications for treatment: a systematic review.

Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis characterized by painful skin ulcerations for which treatment can be challenging. The genetic basis of PG may provide a better understanding of the disease and new targets for treatment. We systematically reviewed the published literature regarding the syndromes and genetic mutations associated with PG. A literature search was performed through the clinical queries PubMed (National Library of Medicine) database and the Cochrane database. The studies were assessed and then categorized as relating to syndromes or specific gene mutations. Two hundred and eight articles were identified, describing 823 cases of PG. A total of 537 (65·2%) cases were associated with inflammatory bowel disease, 133 (16·1%) with polyarthritis and 103 (12·5%) with haematological disorders. Thirty-one cases of pyogenic arthritis, pyoderma gangrenosum and acne, and its variants, were identified. Two patients had mutations in MTHFR and two had mutations in JAK2. Fourteen (1·7%) cases were familial. PG responded to different treatments depending on the setting. For example, treatment with B vitamins improved PG in cases of mutations in MTHFR, whereas patients with myelodysplastic syndrome improved with thalidomide treatment. PG can occur in isolation, associated with systemic disease or as part of various syndromes. Different genetic causes may be best treated with particular treatments. Understanding its genetic basis can help elucidate new potential targets for drug development.

Different dexamethasone doses in the perioperative period improve short-term outcomes of total hip arthroplasty: a randomized controlled trial.

OBJECTIVE: This study aimed to evaluate the efficacy of different dexamethasone doses in the perioperative period of total hip arthroplasty (THA). PATIENTS AND METHODS: We randomly divided 180 patients into three groups: three perioperative saline injections (Group A, placebo); two perioperative doses of 15 mg dexamethasone plus a postoperative saline injection at 48 h (Group B); and three perioperative doses of dexamethasone (10 mg) (Group C). Primary outcomes were postoperative pain at rest and while walking. We also recorded consumption of analgesics and antiemetics, incidence of postoperative nausea and vomiting (PONV), C-reactive protein (CRP) and interleukin-6 (IL-6) levels, postoperative length of stay (p-LOS), range of motion (ROM), nausea, Identity-Consequence-Fatigue-Scale (ICFS), and severe complications (e.g., incidence of surgical site infection, SSI and gastrointestinal bleeding, GIB). RESULTS: Group B and C had significantly lower pain scores at rest than Group A on postoperative day 1. Group B and C also had significantly lower dynamic pain score, CRP, and IL-6 than Group A on postoperative day 1, 2, and 3. Patients in Group B and C had lower PONV incidence, reduced use of analgesics and antiemetics, improved ROM, shorter p-LOS, lower VAS nausea score, and lower ICFS than Group A patients. On postoperative day 3, patients in Group C had significantly lower dynamic pain and ICFS scores, IL-6, and CRP than Group B patients, as well as higher ROM. None of the groups exhibited SSI or GIB. CONCLUSIONS: Dexamethasone provides short-term advantages in reducing pain, PONV, inflammation, and ICFS, and increasing ROM in the early postoperative period after THA. Dexamethasone efficacy in reducing post-THA pain, inflammation, and PONV at 10 mg and 15 mg is similar during the first 48 h. Dexamethasone (30 mg) divided into three 10 mg doses was superior to two doses (15 mg) in reducing pain, inflammation, and ICFS, as well as in increasing ROM on postoperative day 3.

The efficacy of aggressive warming combined with tranexamic acid during total hip arthroplasty: a single-center retrospective study from southern China.

OBJECTIVE: The aim of the study was to evaluate the efficacy of aggressive warming combined with tranexamic acid (TXA) during total hip arthroplasty (THA). PATIENTS AND METHODS: A total of 832 patients who underwent THA from October 2013 to June 2019 were divided into three groups according to the order of admission. There were 210 patients from October 2013 to March 2015 in group A, 302 patients from April 2015 to April 2017 in group B, and 320 patients from May 2017 to June 2019 in group C. Group A was the control group and was not given any measures. Group B was administered intravenously with 15 mg/kg TXA before skin incision and 3 h later without aggressive warming. Group C was administered intravenously with 15 mg/kg TXA before skin incision and 3 h later with aggressive warming. We evaluated the differences in the intraoperative blood loss, changes in core body temperature of patients at different stages during the operation, postoperative drainage, hidden blood loss, transfusion rate, drop of hemoglobin (Hb) on postoperative day 1 (POD1), prothrombin time (PT) of POD1, average hospitalization day, and complications. RESULTS: There were statistically significant differences among the three groups during the intraoperative blood loss, intraoperative changes in core body temperature, postoperative drainage, hidden blood loss, blood transfusion rate, drop of Hb on POD1 and average hospital stay (p<0.05). There was no statistical difference in PT on POD1 and the incidence of complications (p>0.05). CONCLUSIONS: Aggressive warming combined with TXA can significantly reduce the blood loss and transfusion rate of THA, and accelerate the recovery. We also observed that it does not increase the postoperative complications.

Molecular and biological characterization of the murine leukotriene B4 receptor expressed on eosinophils.

The movement of leukocytes into tissues is regulated by the local production of chemical mediators collectively referred to as chemoattractants. Although chemoattractants constitute a diverse array of molecules, including proteins, peptides, and lipids, they all appear to signal leukocytes through a related family of seven transmembrane-spanning G protein-coupled receptors. The eosinophil is a potent proinflammatory cell that is attracted into tissues during allergic inflammation, parasitic infection, and certain malignancies. Since the molecular mechanisms controlling eosinophil recruitment are incompletely understood, we performed a degenerate polymerase chain reaction on cDNA isolated from murine eosinophils to identify novel chemoattractant receptors. We report the isolation of a cDNA that encodes a 351-amino acid glycoprotein that is 78% identical to a human gene that has been reported to be a purinoceptor (P2Y7) and a leukotriene B4 (LTB4) receptor (BLTR). Chinese hamster ovary (CHO) cells transfected with this cDNA specifically bound [3H]LTB4 with a dissociation constant of 0.6 +/- 0.1 nM. Furthermore, LTB4 induced a dose-dependent intracellular calcium flux in transfected CHO cells. In contrast, [35S]dATP did not specifically bind to these transfectants. This mRNA was expressed at high levels in interleukin 5-exposed eosinophils, elicited peritoneal macrophages and neutrophils, and to a lesser extent interferon gamma stimulated macrophages. Low levels of expression were detected in the lung, lymph node, and spleen of unchallenged mice. Western blot analysis detected the mBLTR protein in murine eosinophils and alveolar macrophages as well as human eosinophils. In addition, elevated levels of mBLTR mRNA were found in the lungs of mice in a murine model of allergic pulmonary inflammation in a time course consistent with the influx of eosinophils. Our findings indicate that this murine receptor is an LTB4 receptor that is highly expressed on activated leukocytes, including eosinophils, and may play an important role in mediating eosinophil recruitment into inflammatory foci.

[Application of laser speckle perfusion imaging in predicting wound healing time of burn patients].

Objective: To explore the application effect of laser speckle perfusion imaging (LSPI) in predicting wound healing time of burn patients. Methods: LSPI was performed in 84 adult burn patients hospitalized in department of burns of Tongren Hospital of Wuhan University & Wuhan Third Hospital within post injury hour (PIH) 24 to 72 to detect the blood perfusion values of the wounds. The wound healing time was recorded. The 128 wounds were divided into superficial group (wound healing time shorter than or equal to 14 d, n=57) and deep group (wound healing time longer than 14 d and shorter than or equal to 28 d, n=71) according to the healing time. The blood perfusion values of the two groups were compared. Data were processed with t test or chi-square test. The receiver operating characteristic (ROC) curve was drawn and Youden index was calculated to determine the optimal critical blood perfusion value of wound healing time of the two groups, and the validity of the critical value was assessed by Kappa consistency test. Results: (1) The blood perfusion value of woundsin superficial group was (6.8±1.8) perfusion unit (PU), which was significantly higher than (3.5±1.3) PU in deep group (t=11.404, P<0.01). (2) The total area under ROC curve of blood perfusion value to predict wound healing time was 0.931 (with 95% confidence interval 0.887-0.975, P<0.01). Combined with Youden index, 5.52 PU was chosen as the optimal critical value of wound healing time of the two groups, with sensitivity of 76.9% and specificity of 94.7%. (3) The healing time of 44 wounds predicted was shorter than or equal to 14 d, and the healing time of 84 wounds predicted was longer than 14 d and shorter than or equal to 28 d, while the actual number of wounds was 57 and 71, respectively. The Kappa coefficient of consistency test was 0.754 (P<0.01). Conclusion: LSPI is a useful method to predict the healing time of burn wounds.

Pycnogenol induces differentiation and apoptosis in human promyeloid leukemia HL-60 cells.

Pycnogenol, rich of many phytochemicals of medical value, is a commercialized nutrient supplement extracted from the bark of European coastal pine. In this study, we investigated the anti-tumor effects of Pycnogenol on HL-60, U937 and K562 human leukemia cell lines. We found that Pycnogenol inhibited cell proliferation dose- and time-dependently, and the IC(50)s of Pycnogenol on HL-60, U937 and K562 cells were 150, 40 and 100 microg/ml, respectively. When HL-60 cells were incubated with low concentrations of Pycnogenol (50, 100 and 125 microg/ml) for 24 h, a prominent G0/G1 arrest was observed, followed by gradual accumulation of sub-G0/G1 nuclei. At 48 h of treatment, 50-70% of HL-60 cells differentiated, as evidenced by morphological changes, NBT reduction, induction of NSE activity, and increases of cell surface expression of CD11b. However, results from Annexin V/PI staining, DAPI staining and DNA fragmentation assay indicated that Pycnogenol induced HL-60, U937 and K562 cell apoptosis at their respective IC(50)s after 24 h of treatments. Pretreatment of z-DEVD-fmk, a caspase-3 specific inhibitor, not only decreased caspase-3 activity but also reduced the percentage of apoptotic cells induced by Pycnogenol. This indicated that caspase-3 activation was involved in Pycnogenol induced-apoptosis. In conclusion, Pycnogenol induced differentiation and apoptosis in leukemia cells. Our data suggest that Pycnogenol could serve as a potent cancer chemopreventive or chemotherapeutic agent for human leukemia.

Radical additions of TEMPO to ketenes: correlation of free radical and nucleophilic reactivity.

[reaction: see text] Tetramethylpiperidinyloxy (TEMPO, TO*) reacts with a variety of ketenes R1R2C=C=O by rate-limiting attack on carbonyl carbon to give the 1,2-bis(adducts) R1R2C(OT)CO2T. The alpha,beta-unsaturated ketenes (E)-PhCH=CHCH=C=O (8b) and PhC=CCH=C=O (8c) give the 1,4-bis(adducts) PhCH(OT)CH=CHCO2T and PhC(OT)=C=CHCO2T. The ketenes may be generated in situ for these reactions in the presence of TEMPO by either dehydrochlorination of R1R2CHCOCl with Et3N or Wolff rearrangement. Ketenes PhCH=C=O (8a), 8b, and 8c had not previously been observed as long-lived species at room temperature, but when formed by photochemical Wolff rearrangement, these could be characterized in solution by conventional IR spectroscopy and used for kinetic studies for reaction with TEMPO using UV detection. The reactions of six ketenes with TEMPO in hydrocarbon solvents follow second-order kinetics, with a range of 2.5 x 10(5) in the rate constants, which are correlated with unit slope with the corresponding rate constants for hydration.

Inhibition of xanthine oxidase by some Chinese medicinal plants used to treat gout.

The enzyme xanthine oxidase catalyses the oxidation of hypoxanthine to xanthine and then to uric acid, which plays a crucial role in gout. A total of 122 traditional Chinese medicinal plants, selected according to the clinical efficacy and prescription frequency for the treatment of gout and other hyperuricemia-related disorders, have been evaluated for the enzyme inhibitory activity. Among the 122 methanol extracts derived from these species, 69 were shown to be inhibitory at 100 microg/ml, with 29 having greater than 50% inhibition. As to the equal amount of water extracts, 40 were disclosed to be active at 100 microg/ml, with 13 possessing more than 50% inhibition. At 50 microg/ml, 58 methanol and 24 water extracts exhibited inhibitory activity, with 15 of the former and two of the latter showing greater than 50% inhibition. The most active was the methanol extract of the twig of Cinnamomum cassia (Lauraceae) (IC(50), 18 microg/ml), which was followed immediately by those of the flower of Chrysanthemum indicum (Asteraceae) (IC(50), 22 microg/ml) and the leaves of Lycopus europaeus (Lamiatae) (IC(50), 26 microg/ml). Among the water extracts, the strongest inhibition of the enzyme was observed with that of the rhizome of Polygonum cuspidatum (Polygonaceae) (IC(50), 38 microg/ml). The IC(50) value of allopurinol used as a positive control was 1.06 microg/ml. The study demonstrated that the effects for these medicinal plants used for the gout treatment were based, at least in part, on the xanthine oxidase inhibitory action.

Phenethyl isothiocyanate triggers apoptosis in human malignant melanoma A375.S2 cells through reactive oxygen species and the mitochondria-dependent pathways.

We have reported previously that phenethyl isothiocyanate (PEITC) induces apoptosis in human osteosarcoma U-2 OS cells. Cytotoxic activity of PEITC towards other cancer cells such as human malignant melanoma and skin cancer cells has not been reported. In this study, the anticancer activity of PEITC towards human malignant melanoma cancer A375.S2 cells was investigated. To determine the mechanisms of PEITC inhibition of cell growth, the following end points were determined in A375.S2 cells: cell morphological changes, cell cycle arrest, DNA damage and fragmentation assays and morphological assessment of nuclear change, reactive oxygen species (ROS) and Ca(2+) generations, mitochondrial membrane potential disruption, and nitric oxide and 10-N-nonyl acridine orange productions, expression and activation of caspase-3 and -9, B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax), Bcl-2, poly (adenosine diphosphate-ribose) polymerase, and cytochrome c release, apoptosis-inducing factor and endonuclease G. PEITC induced morphological changes in time- and dose-dependent manner. PEITC induced G2/M phase arrest and induced apoptosis via endoplasmic reticulum stress-mediated mitochondria-dependent pathway. Western blot analysis showed that PEITC promoted Bax expression and inhibited Bcl-2 expression associated with the disintegration of the outer mitochondrial membrane causing cytochrome c release, and activation of caspase-9 and -3 cascade leading to apoptosis. We conclude that PEITC-triggered apoptotic death in A375.S2 cells occurs through ROS-mediated mitochondria-dependent pathways.

Effect of pesticide 1-[6-chloro-3-methyl-pyridyl-8-nitro-7-methyl-1 2 3 5 6 7-hexahydro imidazo (1,2a)]-pyridine when responding to a wheat plant's antioxidant defense system.

The purpose of this research was to establish an analytical method for analysing the 1-[6-chloro-3-methyl-pyridyl-8-nitro-7-methyl-1 2 3 5 6 7-hexahydro imidazo-(1,2a)]-pyridine (IPP) residue levels and to evaluate the difference in plant growth and its physical condition. A high performance liquid chromatography connected to a diode array detector (HPLC-DAD) was also employed. The results showed that the content of protein and water soluble carbohydrate (WSC) treated by IPP were initially higher with a significant delayed decrease. The biomarker response showed, even at a lower dose rate, exposure to the IPP caused stress effects and modified the activity of superoxide dismutase (SOD), guaiacol peroxidase (POD), catalase (CAT) and polyphenol oxidase (PPO). Different patterns of biomarker responses were observed by an increase in SOD and malondialdehyde (MDA), and differential effects for antioxidant enzymes with a decrease in CAT, POD and PPO. The conclusions show that this profile of biomarker variation could represent a useful method to characterise exposure to IPP in a wheat plant.