Preparation, characterization, antioxidant, and antifungal activity of phenyl/indolyl-acyl chitooligosaccharides.

In this study, carboxylic acids compounds were grafted onto chitooligosaccharides to prepare seven phenyl/indolyl-acyl chitooligosaccharides derivatives. The structures of the derivatives were characterized by IR spectroscopy, 13C NMR and elemental analysis. Meanwhile, antioxidant activities in vitro of the novel derivatives were analyzed. Compared to COS and carboxylic acid, the derivatives showed higher scavenging capacity for superoxide anion and DPPH radicals, with scavenging rates of 59.39% and 94.86%, respectively. The hydroxyl radical scavenging ability of the derivatives was only 18.89%. The antifungal activities of chitooligosaccharide derivatives against Diaporthe batatas and Phytophthora capsici were studied by the growth rate method. Compared with chitooligosaccharide itself, derivatives were inhibited by 97.77% and 100%. The above results showed that chitooligosaccharide derivatives have good biocompatibility and can be used in food, agriculture and medicine.

Preparation, characterization, antioxidant and antifungal activities of benzoic acid compounds grafted onto chitosan.

The current study created three novel chitosan derivatives named BACS, PIBACS, and MHBACS by grafting benzoic acid (BA), p-isopropyl benzoic acid (PIBA), and m-hydroxybenzoic acid (MHBA) onto chitosan (CS). The structures of the derivatives were investigated using infrared spectroscopy (FT-IR) and nuclear magnetic resonance (13C NMR). The derivatives were discovered to be 45.06 %-60.49 % substituted using elemental analysis (EA). Based on the findings of in vitro antioxidant experiments (hydroxyl radical scavenging activity, superoxide anion radical scavenging activity, and DPPH radical scavenging activity), all of the derivatives had a higher hydroxyl radical scavenging activity than the chitosan raw material. MHBACS scavenged (31.02 ± 0.90)% of hydroxyl radicals at 0.5 mg/mL, 28.69 % more than chitosan raw. The derivatives scavenged more superoxide anion radicals than the chitosan feedstock at a particular concentration. For instance, at a test dose of 0.2 mg/mL, the scavenging rate of MHBACS on superoxide anion radicals was 7.75 % greater than that of chitosan raw materials. DPPH radical scavenging activity, on the other hand, was not as competent as chitosan feedstock. The growth rate approach was used to assess the potential of the three derivatives to inhibit the development of four phytopathogenic fungi. Chitosan derivatives have better antifungal efficacy than chitosan raw materials. PIBACS, MHBACS, BACS, and Wuyiencin inhibited Phytophthora capsici by (98.03 ± 1.95)%, (81.73 ± 1.63)%, (66.38 ± 1.81)%, and (93.01 ± 2.69)%, respectively, at 1.0 mg/mL. PIBACS had a higher inhibitory impact on Phytophthora capsici than the positive control. Based on the evidence presented above, it is reasonable to conclude that the addition of benzoic acid molecules increased the antioxidant and antifungal capabilities of chitosan.

Chitooligosaccharide-induced plant stress resistance.

In nature, the production of plant stress resistance traits is often induced by extreme environmental conditions. Under extreme conditions, plants can be irreversibly damaged. Intervention with phytostimulants, however, can improve plant stress resistance without causing damage to the plants themselves, hence maintaining the production. For example, exogenous substances such as proteins and polysaccharides can be used effectively as phytostimulants. Chitooligosaccharide, a plant stimulant, can promote seed germination and plant growth and development, and improve plant photosynthesis. In this review, we summarize progress in the research of chitooligosaccharide-induced plant stress resistance. The mechanism and related experiments of chitooligosaccharide-induced resistance to pathogen, drought, low-temperature, saline-alkali, and other stresses are classified and discussed. In addition, we put forward the challenges confronted by chitooligosaccharide-induced plant stress resistance and the future research concept that requires multidisciplinary cooperation, which could provide data for the in-depth study of the effect of chitooligosaccharide on plants.

The preparation and antioxidant activities of four 2-aminoacyl-chitooligosaccharides.

Chitooligosaccharides (COS) with two different molecular weights are acylated with four nonpolar amino acids: glycine (Gly), alanine (Ala), valine (Val) and leucine (Leu) to obtain 2-aminoacetyl-chitooligosaccharide (2-GlyCOS), 2-aminopropionyl-chitooligosaccharide (2-AlaCOS), 2-amino-3-methylbutyryl-chitooligosaccharide (2-ValCOS), and 2-amino-4-methylpentanoyl-chitooligosaccharide (2-LeuCOS). The structure of the derivatives was characterized by FT-IR spectroscopy, 13C NMR spectroscopy, and elemental analysis. The antioxidant activities of the derivatives, such as hydroxyl radical (·OH) scavenging ability, superoxide anion (O2·-) scavenging ability, reducing ability, and DPPH radical scavenging ability, were investigated using various established systems. Compared with chitooligosaccharide and nonpolar amino acids, all derivatives have strong scavenging ability toward hydroxyl radicals and superoxide anions, and the clearance rate was 19.05% and 67.70% separately. The reducing ability and DPPH free radical scavenging ability of the derivatives are only 0.021Abs and 32.97%. Among them, only 2-AlaLCOS has significant reducing ability, and the value can reach 0.143Abs. The above results showed that the antioxidant activity of some derivatives was higher than that of chitooligosaccharide. The water solubility of the new derivatives was also greatly improved compared to that of nonpolar amino acids. Therefore, the application of 2-aminoacyl-chitooligosaccharides (2-AACOS) in antioxidants has laid a foundation and has certain potential application value in the fields of medicine, agriculture, and animal husbandry.

The preparation and antioxidant activities of three phenyl-acylchitooligosaccharides.

Chitooligosaccharides with two different molecular weights are acylated with three containing benzene carboxylic acids: salicylic acid (BHA), α-naphthylacetic acid (NAA) and indole-3-butyric acid (IBA) to obtain o-hydroxybenzoyl-chitooligosaccharide, α-naphthylacetyl-chitooligosaccharide, and 3-Indolebutyryl-chitooligosaccharide. The structure of the derivatives was characterized by FT-IR spectroscopy, 13C NMR spectroscopy and elemental analysis. According to several amide characteristic absorption peaks between 1750 cm-1-1500 cm-1 in the FT-IR spectrum, it can be determined that the target group has been successfully grafted. And there are obvious characteristic absorption peaks of aromatic ring at 900-650 cm-1. The six chemical shifts of 98.02, 76.42, 74.83, 72.00, 60.39, 55.37 ppm in 13C NMR proved that the chitooligosaccharide did not destroy its own sugar ring structure during the reaction. The antioxidant activities of the derivatives, such as hydroxyl radical (·OH) scavenging ability, superoxide anion (O2·-) scavenging ability, reducing ability, and DPPH radical scavenging ability were investigated using various established systems. Comparing with chitooligosaccharide and containing benzene carboxylic acids, most derivatives have strong scavenging ability toward superoxide anions and DPPH radicals, and the clearance rate up to 47.44% and 80.27% separately. The reducing ability and hydroxyl free radical scavenging ability of the derivatives are only 0.032 Abs and 11.43%. The above results showed that the antioxidant activity of some derivatives was higher than that of chitooligosaccharide. The water solubility of the new derivatives was also greatly improved than that of containing benzene carboxylic acids. Therefore, the application of phenyl-acyl-chitooligosaccharide in antioxidants has laid a foundation, and has certain potential application value in the fields of medicine and agriculture and animal husbandry.

[Gene expression profiling of testicular seminoma via bioinformatical analysis].

OBJECTIVE: To investigate the differentially expressed genes related to the survival of testicular seminoma patients and the pathogenesis of the malignancy. METHODS: We obtained the gene expression profiling of testicular seminoma data set GSE8607 from the GEO database and differentially expressed genes in testicular seminoma using the GEO2R online tool. We performed GO and KEGG pathway enrichment via the DAVID website, screened testicular seminoma-related core genes using the STRING and Cytoscape software, and analyzed the survival rate and expression level associated with the core genes through the Kaplan Meier plotter and GEPIA websites. RESULTS: Totally, 591 differentially expressed genes were identified, of which 216 were up-regulated and mainly enriched in 23 biological processes, 8 cell components, 5 biological functions and 7 KEGG pathways, and the other 375 down-regulated and enriched only in the biological process, involving the formation and development of spermatozoa. Thirty-two core genes were obtained via PPI network analysis, including C1QB, CCL2, CCR2, GPR183, ELL, LAPTM5, NPY5R, CD28 and MMP9, which were closely related to the survival rate (P < 0.05), C1QB, CCL2, CCR2, SELL, LAPTM5, CD28 and MMP9, which were highly expressed in the testicular seminoma tissue (P < 0.05), and NPY5R, which was lowly expressed in the testicular seminoma tissue (P < 0.05). CONCLUSIONS: The 8 differentially expressed genes identified in the testicular seminoma tissue contribute to effective prediction of the survival rate of the patients as well as to the diagnosis, prevention and treatment of the disease and development of new anti-cancer drugs.

Preparation, characterization and antimicrobial activities of cyclic substituted chitosan derivatives.

Six cyclic substituted chitosan derivatives were synthesized, and their structures were characterized by FTIR, 13C NMR and elemental analyses. Additionally, their antimicrobial properties were studied. The synthesized derivatives showed significantly greater zones of inhibition compared with chitosan. The zone of inhibition values produced by C2-2-naphthylamine formamide-C6-2-naphthylamine formyl ester-polymer chitosan against Sarcina sp., Staphylococcus aureus and Escherichia coli were 24 mm, 21 mm and 21 mm, respectively, whereas those of C2-cyclohexylamine formamide-C6-cyclohexylamine formyl ester-low chitosan against Fusarium equiseti and Verticillium dahliae were 14 mm and 15 mm, respectively. The antibacterial abilities of chitosan and its derivatives against the Gram-positive bacteria Sarcina sp. and Staphylococcus aureus were stronger than those against the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa. In addition, all of the high and low molecular weight chitosan derivatives showed greater bacteriostatic activities than antifungal activities. The results provided a useful reference for the development of chitosan and its derivatives used as new pesticides.

Clinical characteristics of 2,459 severe or critically ill COVID-19 patients: A meta-analysis.

ABSTRACT: Our study aims to summarize the clinical characteristics of patients with severe or critically ill coronavirus disease 2019 (COVID-19).Five databases were electronically searched to collect studies describing clinical characteristics of severe or critically ill COVID-19 patients and published between January 1, 2020 and April 12, 2020. Three reviewers independently collected the literature, extracted the required data, and assessed the risk of publication bias of the included studies before including the studies in the meta-analysis.A total of 40 studies involving 2459 patients with severe or critically ill COVID-19 patients were included. Meta-analysis showed that a greater proportion of severe or critically COVID-19 patients were male (62.3%), and the 2 main clinical symptoms were fever (87.4%) and cough (66.3%). Other common clinical symptoms included dyspnea (45.3%), chest tightness (37.4%), fatigue (36.6%), and expectoration (31.9%). Minor symptoms included myalgia (19.5%), dizziness (11.5%), headache (11.4%), diarrhea (11.2%), pharyngalgia (11.0%), nausea, and vomiting (5.9%). Most patients showed elevated levels of C-reactive protein (83.5%) and D-dimer (73.3%), lymphopenia (70.3%), and normal leukocyte counts (56.9%). Other findings included abnormal levels of liver function (39.8%), elevated procalcitonin (36.6%), leukocytosis (21.7%), thrombocytopenia (19.0%), and leucopenia (18.2%). Most patients showed acute respiratory distress syndrome (60.8%). Other complications included acute cardiac injury (37.1%), shock (32.0%), and acute kidney injury (22.0%).The most common symptoms of severe or critically ill COVID-19 patients were fever and cough. Most patients showed lymphopenia, elevated levels of C-reactive protein and D-dimer. A large percentage of patients progress to ARDS, acute cardiac injury, acute kidney injury and shock were also common.

Identification of Genes with Altered Methylation and Its Role in Early Diagnosis of Sepsis-Induced Acute Respiratory Distress Syndrome.

PURPOSE: Early diagnosis of sepsis-induced acute respiratory distress syndrome (ARDS) is critical for effective treatment. We aimed to identify early stage biomarkers. MATERIALS AND METHODS: Differentially expressed genes were identified in whole blood samples from patients with sepsis or ARDS based on the Gene Expression Omnibus (GEO) datasets GSE32707, GSE54514 and GSE10361. Functional enrichment analysis explored the biological characteristics of differentially expressed genes. Genes with high functional connectivity based on a protein-protein interaction network were marked as hub genes, which were validated using the GEO dataset GSE76293, and a gene set variation analysis index (GSVA) was assigned. Diagnostic and predictive ability of the hub genes were assessed by receiver operating characteristic (ROC) curve analysis. DNA methylation levels of hub genes were quantified using the GEO dataset GSE67530. RESULTS: Forty-one differentially expressed genes were shared between sepsis-specific and ARDS-specific datasets. MAP2K2 and IRF7 functional activity was highly connected in sepsis-induced ARDS. Hub genes included RETN, MVP, DEFA4, CTSG, AZU1, FMNL1, RBBP7, POLD4, RIN3, IRF7. ROC curve analysis of the hub gene GSVA index showed good diagnostic ability in sepsis or ARDS. Among genes related to sepsis-induced ARDS, 17 were differentially methylated. Principal component analysis and heatmaps indicated that gene methylation patterns differed significantly between ARDS patients and controls. CONCLUSION: We identified a genetic profile specific to early-stage sepsis-induced ARDS. The abnormal expression of these genes may be caused by hypomethylation, which may serve as a biomarker for early diagnosis of ARDS.

Coagulation dysfunction is associated with severity of COVID-19: A meta-analysis.

To systematically analyze the blood coagulation features of coronavirus disease 2019 (COVID-19) patients to provide a reference for clinical practice. An electronic search in PubMed, EMbase, Web of Science, Scopus, CNKI, WanFang Data, and VIP databases to identify studies describing the blood coagulation features of COVID-19 patients from 1 January 2020 to 21 April 2020. Three reviewers independently screened literature, extracted data, and assessed the risk of bias of included studies, then, the meta-analysis was performed by using Stata 12.0 software. Thirty-four studies involving 6492 COVID-19 patients were included. Meta-analysis showed that patients with severe disease showed significantly lower platelet count (weighted mean differences [WMD]: -16.29 × 109 /L; 95% confidence interval [CI]: -25.34 to -7.23) and shorter activated partial thromboplastin time (WMD: -0.81 seconds; 95% CI: -1.94 to 0.33) but higher D-dimer levels (WMD: 0.44 µg/mL; 95% CI: 0.29-0.58), higher fibrinogen levels (WMD: 0.51 g/L; 95% CI: 0.33-0.69) and longer prothrombin time (PT; WMD: 0.65 seconds; 95% CI: 0.44-0.86). Patients who died showed significantly higher D-dimer levels (WMD: 6.58 µg/mL; 95% CI: 3.59-9.57), longer PT (WMD: 1.27 seconds; 95% CI: 0.49-2.06) and lower platelet count (WMD: -39.73 × 109 /L; 95% CI: -61.99 to -17.45) than patients who survived. Coagulation dysfunction is common in severe COVID-19 patients and it is associated with severity of COVID-19.

[Regulatory effect of Jinkui Shenqi Pills on the gene expression of the Nrf2 signaling pathway in cyclophosphamide-induced testis injury in mice].

OBJECTIVE: To investigate the protective effect of Jinkui Shenqi Pills (JSP) against cyclophosphamide-induced testis injury (TI) and its anti-oxidation mechanism in mice. METHODS: Thirty male mice were equally divided into a blank control, a TI model control and a JSP treatment group. The mice in the JSP treatment group were treated intragastrically with JSP and the blank controls with normal saline at 1.2 g/kg qd for 7 days, and then the animals in both the TI model control and JSP treatment groups were injected intraperitoneally with cyclophosphamide at 50 mg/kg, once a week, for 35 days, to induce testis injury. After modeling, all the mice were weighed and sacrificed, followed by detection of the serum T content, measurement of the testis weight, examination of semen parameters in the caudad epididymis, and determination of the levels of super oxide dismutase (SOD) and malondialdehyde (MDA) in the testis tissue and the expressions of relevant genes by qRT-PCR. RESULTS: The mice of the TI model control group, compared with the blank controls, showed significant decreases in the body weight (ï¼»34.63 ± 1.92ï¼½ vs ï¼»48.32 ± 1.64ï¼½ g, P<0.05), testis weight (ï¼»80.00 ± 3.90ï¼½ vs ï¼»140.00 ± 6.10ï¼½ mg, P<0.05), testicular organ coefficient (ï¼»0.22 ± 0.01ï¼½ vs ï¼»0.31 ±0.03ï¼½%, P<0.05), sperm motility (ï¼»48.66 ± 8.08ï¼½% vs ï¼»89.33 ± 4.04ï¼½%, P<0.05), sperm concentration (ï¼»28.42 ± 5.26ï¼½ vs ï¼»77.67 ± 8.73ï¼½ ×106/ml, P<0.05), and levels of serum T (ï¼»8.75 ± 0.96ï¼½ vs ï¼»21.75 ± 1.71ï¼½ pg/ml, P<0.05) and SOD (ï¼»140.82 ± 10.08ï¼½ vs ï¼»358.52 ± 40.41ï¼½ U/mg prot, P<0.05), but remarkable increases in the sperm deformity rate (ï¼»37.33 ± 2.08ï¼½ vs ï¼»15.33±1.53ï¼½%, P<0.05) and MDA level (ï¼»54.89±6.09ï¼½ vs ï¼»30.21±2.17ï¼½ nmol/ng prot, P<0.05). The mice of the JSP treatment group, in comparison with the TI model controls, exhibited markedly increased body weight (ï¼»39.80±2.89ï¼½ vs ï¼»34.63±1.92ï¼½g, P<0.05), testis weight (ï¼»130.00 ± 11.00ï¼½ vs ï¼»80.00 ± 3.90ï¼½ mg, P<0.05), testicular organ coefficient (ï¼»0.28 ± 0.01ï¼½ vs ï¼»0.22 ± 0.01ï¼½%, P<0.05), sperm motility (ï¼»76.00 ± 5.29ï¼½% vs ï¼»48.66 ± 8.08ï¼½%, P<0.05), sperm concentration (ï¼»56.08 ± 4.29ï¼½ vs ï¼»28.42 ± 5.26ï¼½ ×106/ml, P<0.05), and levels of serum T (ï¼»15.50 ± 1.29ï¼½ vs ï¼»8.75 ± 0.96ï¼½ pg/ml, P<0.05) and SOD (ï¼»206.59 ± 16.38ï¼½ vs ï¼»140.82 ± 10.08ï¼½ U/mg prot, P<0.05), but decreased sperm deformity rate (ï¼»25.01 ± 2.99ï¼½% vs ï¼»37.33 ± 2.08ï¼½%, P<0.05) and MDA level (ï¼»35.84 ± 3.61ï¼½ vs ï¼»54.89 ± 6.09ï¼½ nmol/ng prot, P<0.05). The mRNA expressions of NOQ-1, Nrf2 and HO-1 in the testis tissue were significantly lower and that of Caspase-3 remarkably higher in the TI model control than in the blank control group (P<0.05), while those of Nrf2 and HO-1 significantly higher and that of Caspase-3 markedly lower in the JSP treatment group than in the TI model controls (P<0.05). Histopathological images displayed reduced layers of spermatogenic cells in the seminiferous tubules, complete exfoliation of the spermatogenic cells in some of the tubules and decreased number of sperm cells in the TI model controls, which were all found normal in the JSP treatment group. CONCLUSIONS: Jinkui Shenqi Pills can effectively inhibit cyclophosphamide-induced testis injury, which may be related to its effect of regulating the gene expression of the Nrf2 signaling pathway and enhancing the activity of antioxidant enzymes.

Association of elevated inflammatory markers and severe COVID-19: A meta-analysis.

Our study aimed to assess the existing evidence on whether severe coronavirus disease 2019 (COVID-19) is associated with elevated inflammatory markers.The PubMed, Embase, Web of Science, Scopus, Chinese National Knowledge Infrastructure, WanFang, and China Science and Technology Journal databases were searched to identify studies published between January 1 and April 21, 2020 that assayed inflammatory markers in COVID-19 patients. Three reviewers independently examined the literature, extracted relevant data, and assessed the risk of publication bias before including the meta-analysis studies.Fifty-six studies involving 8719 COVID-19 patients were identified. Meta-analysis showed that patients with severe disease showed elevated levels of white blood cell count (WMD: 1.15, 95% CI: 0.78-1.52), C-reactive protein (WMD: 38.85, 95% CI: 31.19-46.52), procalcitonin (WMD: 0.08, 95% CI: 0.06-0.11), erythrocyte sedimentation rate (WMD: 10.15, 95% CI: 5.03-15.46), interleukin-6 (WMD: 23.87, 95% CI: 15.95-31.78), and interleukin-10 (WMD: 2.12, 95% CI: 1.97-2.28). Similarly, COVID-19 patients who died during follow-up showed significantly higher levels of white blood cell count (WMD: 4.11, 95% CI: 3.25-4.97), C-reactive protein (WMD: 74.18, 95% CI: 56.63-91.73), procalcitonin (WMD: 0.26, 95% CI: 0.11-0.42), erythrocyte sedimentation rate (WMD: 10.94, 95% CI: 4.79-17.09), and interleukin-6 (WMD: 59.88, 95% CI: 19.46-100.30) than survivors.Severe COVID-19 is associated with higher levels of inflammatory markers than a mild disease, so tracking these markers may allow early identification or even prediction of disease progression.

Risk factors of severe cases with COVID-19: a meta-analysis.

Our study aimed to systematically analyse the risk factors of coronavirus disease 2019 (COVID-19) patients with severe disease. An electronic search in eight databases to identify studies describing severe or critically ill COVID-19 patients from 1 January 2020 to 3 April 2020. In the end, we meta-analysed 40 studies involving 5872 COVID-19 patients. The average age was higher in severe COVID-19 patients (weighted mean difference; WMD = 10.69, 95%CI 7.83-13.54). Patients with severe disease showed significantly lower platelet count (WMD = -18.63, 95%CI -30.86 to -6.40) and lymphocyte count (WMD = -0.35, 95%CI -0.41 to -0.30) but higher C-reactive protein (CRP; WMD = 42.7, 95%CI 31.12-54.28), lactate dehydrogenase (LDH; WMD = 137.4, 95%CI 105.5-169.3), white blood cell count（WBC), procalcitonin（PCT）, D-dimer, alanine aminotransferase (ALT), aspartate aminotransferase (AST) and creatinine（Cr）. Similarly, patients who died showed significantly higher WBC, D-dimer, ALT, AST and Cr but similar platelet count and LDH as patients who survived. These results indicate that older age, low platelet count, lymphopenia, elevated levels of LDH, ALT, AST, PCT, Cr and D-dimer are associated with severity of COVID-19 and thus could be used as early identification or even prediction of disease progression.

Two gene set variation indexes as potential diagnostic tool for sepsis.

Accurate diagnosis of sepsis remains challenging, new markers or combinations of markers are urgently needed. In the present study, we screened differentially expressed genes (DEGs) between sepsis and non-sepsis blood samples across three previously published gene expression data sets. Common upregulated and downregulated DEGs were ranked according to their average functional similarity. The ten genes (OLFM4, ORM1, CEP55, S100A12, S100P, LRG1, CEACAM8, MS4A4A, PLSCR1, and IL1R2) with the largest average functional similarity among the common upregulated genes and another ten genes (THEMIS, IL2RB, CD2, IL7R, CD3E, KLRB1, PVRIG, CCRR3, TGFBR3, and PLEKHA1) with the largest average functional similarity among the common downregulated genes were separately identified as the upregulated crucial gene set and the downregulated crucial gene set. Gene set variation analysis (GSVA) was used to obtain the GSVA index of each sample against the two crucial gene sets. Both the two crucial GSVA indexes may be robust markers for sepsis with high area under ROC curve. The diagnostic utility of the upregulated GSVA index was validated in another independent data set. Functional analyses revealed several sepsis-related pathways. In conclusion, we proposed two sepsis-related gene sets across multiple data sets and created two GSVA indexes with promising diagnostic value.

Clinicopathological characteristics of 8697 patients with COVID-19 in China: a meta-analysis.

OBJECTIVE: Our study aims to present a summary of the clinicopathological characteristics of patients affected by the coronavirus disease 2019 (COVID-19) that can be used as a reference for further research and clinical decisions. DESIGN: Studies were included in the meta-analysis if they had cohort, case-control or case series designs and provided sufficient details on clinical symptoms, laboratory outcomes and asymptomatic patients. SETTING: PubMed, Embase, Chinese Biomedical Literature Database, Wanfang, China Science and Technology Journal Database and China National Knowledge Infrastructure databases were electronically searched to identify related studies published between 1 January 2020 and 16 March 2020. Three reviewers independently examined the literature, extracted relevant data and assessed the risk of publication bias before including the studies in the meta-analysis. PARTICIPANTS: The confirmed cases of COVID-19. RESULTS: A total of 55 unique retrospective studies involving 8697 patients with COVID-19 were identified. Meta-analysis showed that a higher proportion of infected patients were male (53.3%), and the two major symptoms observed were fever (78.4%) and cough (58.3%). Other common symptoms included fatigue (34%), myalgia (21.9%), expectoration (23.7%), anorexia (22.9%), chest tightness (22.9%) and dyspnoea (20.6%). Minor symptoms included nausea and vomiting (6.6%), diarrhoea (8.2%), headache (11.3%), pharyngalgia (11.6%), shivering (15.2%) and rhinorrhea (7.3%). About 5.4% of the patients were asymptomatic. Most patients showed normal leucocyte counts (64.7%) and elevated C reactive protein levels (65.9%). Lymphopaenia was observed in about 47.6% of the infected patients, along with abnormal levels of myocardial enzymes (49.4%) and liver function (26.4%). Other findings included leucopenia (23.5%), elevated D-dimer (20.4%), elevated erythrocyte sedimentation rate (20.4%), leucocytosis (9.9%), elevated procalcitonin (16.7%) and abnormal renal function (10.9%). CONCLUSIONS: The most commonly experienced symptoms of patients with COVID-19 were fever and cough. Myalgia, anorexia, chest tightness and dyspnoea were found in some patients. A relatively small percentage of patients were asymptomatic and could act as carriers of the disease. Most patients showed normal leucocyte counts, elevated levels of C reactive protein and lymphopaenia, confirming the viral origin of the disease.

Clinical characteristics of 3062 COVID-19 patients: A meta-analysis.

We aimed to systematically review the clinical characteristics of coronavirus disease 2019 (COVID-19). Seven databases were searched to collect studies about the clinical characteristics of COVID-19 from January 1, 2020 to February 28, 2020. Then, meta-analysis was performed by using Stata12.0 software. A total of 38 studies involving 3062 COVID-19 patients were included. Meta-analysis showed that a higher proportion of infected patients was male (56.9%). The incidence rate of respiratory failure or acute respiratory distress syndrome was 19.5% and the fatality rate was 5.5%. Fever (80.4%), fatigue (46%), cough (63.1%), and expectoration (41.8%) were the most common clinical manifestations. Other common symptoms included muscle soreness (33%), anorexia (38.8%), chest tightness (35.7%), shortness of breath (35%), dyspnea (33.9%). Minor symptoms included nausea and vomiting (10.2%), diarrhea (12.9%), headache (15.4%), pharyngalgia (13.1%), shivering (10.9%), and abdominal pain (4.4%). The proportion of patients that was asymptomatic was 11.9%. Normal leukocyte counts (69.7%), lymphopenia (56.5%), elevated C-reactive protein levels (73.6%), elevated ESR (65.6%), and oxygenation index decreased (63.6%) were observed in most patients. About 37.2% of patients were found with elevated D-dimer, 25.9% of patients with leukopenia, along with abnormal levels of liver function (29%), and renal function (25.5%). Other findings included leukocytosis (12.6%) and elevated procalcitonin (17.5%). Only 25.8% of patients had lesions involving a single lung and 75.7% of patients had lesions involving bilateral lungs. The most commonly experienced symptoms of COVID-19 patients were fever, fatigue, cough, and expectoration. A relatively small percentage of patients were asymptomatic. Most patients showed normal leucocytes counts, lymphopenia, elevated levels of C-reactive protein and ESR. Bilateral lung involvement was common.

CT imaging features of 4121 patients with COVID-19: A meta-analysis.

OBJECTIVE: We systematically reviewed the computed tomography (CT) imaging features of coronavirus disease 2019 (COVID-19) to provide reference for clinical practice. METHODS: Our article comprehensively searched PubMed, FMRS, EMbase, CNKI, WanFang databases, and VIP databases to collect literatures about the CT imaging features of COVID-19 from 1 January to 16 March 2020. Three reviewers independently screened literature, extracted data, and assessed the risk of bias of included studies, and then, this meta-analysis was performed by using Stata12.0 software. RESULTS: A total of 34 retrospective studies involving a total of 4121 patients with COVID-19 were included. The results of the meta-analysis showed that most patients presented bilateral lung involvement (73.8%, 95% confidence interval [CI]: 65.9%-81.1%) or multilobar involvement (67.3%, 95% CI: 54.8%-78.7%) and just little patients showed normal CT findings (8.4%). We found that the most common changes in lesion density were ground-glass opacities (68.1%, 95% CI: 56.9%-78.2%). Other changes in density included air bronchogram sign (44.7%), crazy-paving pattern (35.6%), and consolidation (32.0%). Patchy (40.3%), spider web sign (39.5%), cord-like (36.8%), and nodular (20.5%) were common lesion shapes in patients with COVID-19. Pleural thickening (27.1%) was found in some patients. Lymphadenopathy (5.4%) and pleural effusion (5.3%) were rare. CONCLUSION: The lung lesions of patients with COVID-19 were mostly bilateral lungs or multilobar involved. The most common chest CT findings were patchy and ground-glass opacities. Some patients had air bronchogram, spider web sign, and cord-like. Lymphadenopathy and pleural effusion were rare.

Global transcriptional regulation of STAT3- and MYC-mediated sepsis-induced ARDS.

BACKGROUND: In recent years, sepsis-induced acute respiratory distress syndrome (ARDS) has remained a major clinical challenge for patients in intensive care units. While some progress has been reported over the years, the pathogenesis of ARDS still needs to be further expounded. METHODS: In the present study, gene set enrichment analysis, differentially expressed genes analysis, short time-series expression miner, protein-protein interaction (PPI) networks, module analysis, hypergeometric test, and functional enrichment analysis were performed in whole blood gene expression profiles of sepsis and induced-sepsis ARDS to explore the molecular mechanism of sepsis-induced ARDS. RESULTS: Further dysregulated genes in the process evolving from healthy control through sepsis to sepsis-induced ARDS were identified and organized into 10 functional modules based on their PPI networks. These functional modules were significantly involved in cell cycle, ubiquitin mediated proteolysis, spliceosome, and other pathways. MYC, STAT3, LEF1, and BRCA1 were potential transcription factors (TFs) regulating these modules. A TF-module-pathway global regulation network was constructed. In particular, our findings suggest that MYC and STAT3 may be the key regulatory genes in the underlying dysfunction of sepsis-induced ARDS. Receiver operating characteristic curve analysis showed the core genes in the global regulation network may be biomarkers for sepsis or sepsis-induced ARDS. CONCLUSIONS: We found that MYC and STAT3 may be the key regulatory genes in the underlying dysfunction of sepsis-induced ARDS. The reviews of this paper are available via the supplementary material section.

Synthesis, characterization and biological activity of C6-Schiff bases derivatives of chitosan.

C6-Schiff bases derivatives of chitosan were synthesized for the first time. C2-amino groups and C3-hydroxy groups were firstly protected by CuSO4·5H2O, and the C6-hydroxy was then transformed into aldehyde, which then reacted with anilines through nucleophilic addition to introduce the CN group at C6-position in chitosan chain. Finally, C6-Schiff bases derivatives of chitosan were got by the deprotection of C2-NH2 with cation exchange resin. The structures and properties of the new synthesized products were characterized by Fourier transform infrared spectroscopy, 13C NMR, SEM image, and elemental analysis. The antibacterial activities of derivatives were tested in the experiment, and the results showed that the prepared chitosan derivatives had significantly improved antibacterial activity toward Staphylococcus aureus and Escherichia coli. The Cytotoxicity test showed that the prepared chitosan derivatives had low Cytotoxicity, compared with chitosan and C2-benzaldehyde Schiff bases of chitosan. This paper allowed a new method for the synthesis of Schiff bases of chitosan, which was enlightening.