COVID-19 cases from the first local outbreak of SARS-CoV-2 B.1.1.7 variant in China presented more serious clinical features: a prospective, comparative cohort study

BackgroundThe SARS-CoV-2 B.1.1.7 variant which was first identified in the United Kingdom (U.K.) has increased sharply in numbers worldwide and was reported to be more contagious. On January 17, 2021, a COVID-19 clustered outbreak caused by B.1.1.7 variant occurred in a community in Daxing District, Beijing, China. Three weeks prior, another non-variant (lineage B.1.470) COVID-19 outbreak occurred in Shunyi District, Beijing. This study aimed to investigate the clinical features of B.1.1.7 variant infection. MethodsA prospective cohort study was conducted on COVID-19 cases admitted to Ditan hospital since January 2020. Data of 74 COVID-19 cases from two independent COVID-19 outbreaks in Beijing were extracted as study subjects from a Cloud Database established in Ditan hospital, which included 41 Shunyi cases (Shunyi B.1.470 group) and 33 Daxing cases (Daxing B.1.1.7 group) that have been hospitalized since December 25, 2020 and January 17, 2021, respectively. We conducted a comparison of the clinical characteristics, RT-qPCR results and genomic features between the two groups. FindingsCases from Daxing B.1.1.7 group (15 [45.5%] male; median age, 39 years [range, 30.5, 62.5]) and cases from Shunyi B.1.470 group (25 [61.0%] male; median age, 31 years [range, 27.5, 41.0]) had a statistically significant difference in median age (P =0.014). Seven clinical indicators of Daxing B.1.1.7 group were significantly higher than Shunyi B.1.470 group including patients having fever over 38{degrees}C (14/33 [46.43%] in Daxing B.1.1.7 group vs. 9/41 (21.95%) in Shunyi B.1.470 group [P = 0 .015]), C-reactive protein ([CRP, mg/L], 4.30 [2.45, 12.1] vs. 1.80, [0.85, 4.95], [P = 0.005]), Serum amyloid A ([SAA, mg/L], 21.50 [12.50, 50.70] vs. 12.00 [5.20, 26.95], [P = 0.003]), Creatine Kinase ([CK, U/L]), 110.50 [53.15,152.40] vs. 70.40 [54.35,103.05], [P = 0.040]), D-dimer ([DD, mg/L], 0.31 [0.20, 0.48] vs. 0.24 [0.17,0.31], [P = 0.038]), CD4+ T lymphocyte ([CD4+ T, mg/L], [P = 0.003]), and Ground-glass opacity (GGO) in lung (15/33 [45.45%] vs. 5/41 [12.20%], [P =0.001]). After adjusting for the age factor, B.1.1.7 variant infection was the risk factor for CRP (P = 0.045, Odds ratio [OR] 2.791, CI [1.025, 0.8610]), SAA (0.011, 5.031, [1.459, 17.354]), CK (0.034, 4.34, [0.05, 0.91]), CD4+ T (0.029, 3.31, [1.13, 9.71]), and GGO (0.005, 5.418, [1.656, 17.729]) of patients. The median Ct value of RT-qPCR tests of the N-gene target in the Daxing B.1.1.7 group was significantly lower than the Shunyi B.1.470 group (P=0.036). The phylogenetic analysis showed that only 2 amino acid mutations in spike protein were detected in B.1.470 strains while B.1.1.7 strains had 3 deletions and 7 mutations. InterpretationClinical features including a more serious inflammatory response, pneumonia and a possible higher viral load were detected in the cases infected with B.1.1.7 SARS-CoV-2 variant. It could therefore be inferred that the B.1.1.7 variant may have increased pathogenicity. FundingThe study was funded by the National Key Research and Development Program (grant nos.2020YFC0846200 and 2020YFC0848300) and National Natural Science Foundation of China (grant no. 82072295).

Effect of tannins and cellulase on growth performance, nutrients digestibility, blood profiles, intestinal morphology and carcass characteristics in Hu sheep.

Objective: This study was conducted to evaluate the effects of tannins and cellulase on growth performance, nutrient digestibility, blood profiles, intestinal morphology and carcass characteristics in Hu sheep. Methods: A total of 48 three-month-old meat Hu sheep (25.05 ± 0.9 kg) were blocked based on body weight, and randomly allotted to 4 treatments with 3 replicates of 4 sheep each. The experiment lasted for 80 d, and dietary treatments were as follows: (1) CON, control diet; (2) TAN, CON + 0.1% tannins; (3) CEL, CON + 0.1% cellulase; (4) TAN+ CEL, CON + 0.1% tannins and 0.1% cellulase. Results: Compared with CON, CEL and TAN+CEL had greater (P<0.05) final birth weight (FBW) and average daily gain but lower (P<0.05) F/G, while FBW of TAN+CEL was lower (P<0.05) than that of CEL. The apparent total tract digestibility (ATTD) of DM in TAN, CEL and TAN+CEL groups were higher (P<0.05) than that in CON. CEL and TAN+CEL groups had greater (P<0.05) ATTD of CF compared with TAN and CON, while TAN group had lower (P<0.05) ATTD of CP than other treatments. TAN, CEL and TAN+CEL groups increased (P<0.05) serum globulin and alkaline phosphatase but decreased (P<0.05) A/G. Serum total protein was greatest for TAN+CEL, intermediate for TAN and CEL and least for CON (P<0.05). TAN+CEL group increased (P<0.05) dressing percentage compared with CON, while the backfat thickness of CEL was lower (P<0.05) than that of CON. The villus height of jejunum and ileum in CEL and TAN+CEL groups were greater (P<0.05) than that in CON, and the crypt depth and villus height: crypt depth of jejunum were increased (P<0.05) in TAN, CEL and TAN+CEL groups. Conclusion: The addition of tannins and cellulase together promoted nutrient digestion, liver protein synthesis and intestinal development and thus improved growth performance and carcass characteristics.

Inhibition of Cannabinoid Receptor 1 Can Influence the Lipid Metabolism in Mice with Diet-Induced Obesity.

A growing number of evidences accumulated about critical metabolic role of cannabinoid type 1 receptor (CB1), carnitine palmitoyltransferase-1 (CPT1) and peroxisome proliferator-activated receptors (PPARs) in some peripheral tissues, including adipose tissue, liver, skeletal muscle and heart. To better understand the interactions of CB1, CPT1 and PPARs in these tissues, 30 diet-induced obese (DIO) C57BL/6J male mice were obtained, weight-matched and divided into two groups (15 in each group): (i) DIO/vehicle mice (D-Veh) and (ii) DIO/SR141716 mice (D-SR) treated with SR141716 (or rimonabant, a selective CB1 receptor blocker) administered orally (10 mg/kg daily). Another 15 mice fed standard diet (STD) formed the STD/vehicle group (S-Veh). At the end of 3-week treatment, mean body weight was 28.4 ± 0.5, 36.5 ± 0.8, and 30.3 ± 1.2 g for the S-Veh, D-Veh, and D-SR group, respectively (p < 0.05; D-Veh vs. D-SR). Liver weight in the D-SR group was also decreased significantly compared to the D-Veh group (p < 0.05). Serum levels of total cholesterol, high-density lipoprotein cholesterol, leptin and adiponectin in the D-SR group were ameliorated compared to the D-Veh group (p < 0.05). Both qRT-PCR and Western blot assay revealed that CB1 expression levels were efficiently blocked by SR141716 in subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), skeletal muscles and liver (D-SR vs. D-Veh; p < 0.05), whereas there was no significant difference between S-Veh and D-Veh mice (p > 0.05). Simultaneously with the reduction of CB1 expression in the D-SR group, the expression levels of CPT1A isoform (protein) in the liver and heart and CPT1B isoform (protein) in the SAT, VAT, liver and skeletal muscles were significantly increased (p < 0.05; D-SR vs. D-Veh). Interestingly, the CPT1A and CPT1B expression levels in heart were detected slightly. The expression levels of PPARα in the SAT, VAT, liver and skeletal muscles and PPARγ in the SAT and skeletal muscles in the D-SR group were significantly increased compared to the D-Veh mice (p < 0.05). However, the PPARß expression level differed from that of PPARα and PPARγ. Taken together, these data indicate that the inhibition of CB1 could ameliorate lipid metabolism via the stimulation of the CPT1A and CPT1B expression in vivo. Simultaneously, the PPARα and PPARγ expression levels significantly differed compared to that of PPARß in obesity and lipid metabolism-related disorders under blockade of CB1. Both the mechanism of the influence of CB1 inhibition on lipid metabolism in the examined tissues and the specific mechanism of PPARα, PPARγ and PPARß involvement in lipid exchange under these conditions remain to be further elucidated.

[Serum bone turnover markers and vitamin D level in diabetes patients with and without tuberculosis].

Objective: To investigate the levels of bone turnover marks and vitamin D(25OHD(3))in diabetes patients with and without tuberculosis. Methods: A total of 163 patients were recruited from Beijing Hospital and Jilin Provincial Academy of Tuberculosis Control and Prevention. including 80 diabetes patients without tuberculosis [39 males and 41 females, mean age (59±10) years], and 83 diabetes patients with tuberculosis [34 males and 49 females, mean age (56±12) years]. In the meantime, 80 healthy subjects were recruited as the normal control [39 males and 41 females, mean age (50±8) years]. The blood samples of all participants were taken after 10 hours fasting and before anti-tuberculosis treatment, and the levels of 25OHD(3), ß-crossLaps, Osteocalcin(OCN), and total procollagen type 1 amino-terminal propeptide(tP(1)NP) were meausured. One-way ANOVA and chis-square test were used for comparisons among the 3 groups and between groups respectively. Results: The concentration of 25OHD(3) was higher in diabetes patients without tuberculosis (16 µg/L) than in those with tuberculosis (14 µg/L), P<0.05, but significantly lower than that in the healthy subjects(21 µg/L) (P<0.01). The rate of 25OHD(3) deficiency was 79.8% (130/163) in diabetes patients (with and without tuberculosis), and significantly higher than that in healthy subjects 41.3% (33/80), P<0.01. The rate of serious deficiency of 25OHD(3) was 24.1% (20/83) in diabetes patients with tuberculosis. The level of tP(1)NP in diabetes patients (36 µg/L) was significantly lower than that in diabetes patients with tuberculosis 57 µg/L(P<0.01). Conclusions: 25OHD(3) deficiency was common in diabetes patients with and without tuberculosis. The level of tP(1)NP was significantly lower in diabetes patients without tuberculosis than those with tuberculosis, for which further studies were needed .

Evidence that activation of ASIC1a by acidosis increases osteoclast migration and adhesion by modulating integrin/Pyk2/Src signaling pathway.

Activated acid-sensing ion channel 1a (ASIC1a) is involved in acid-induced osteoclastogenesis by regulating activation of the transcription factor NFATc1. These results indicated that ASIC1a activation by extracellular acid may cause osteoclast migration and adhesion through Ca2+-dependent integrin/Pyk2/Src signaling pathway. INTRODUCTION: Osteoclast adhesion and migration are responsible for osteoporotic bone loss. Acidic conditions promote osteoclastogenesis. ASIC1a in osteoclasts is associated with acid-induced osteoclastogenesis through modulating transcription factor NFATc1 activation. However, the influence and the detailed mechanism of ASIC1a in regulating osteoclast adhesion and migration, in response to extracellular acid, are not well characterized. METHODS: In this study, knockdown of ASIC1a was achieved in bone marrow macrophage cells using small interfering RNA (siRNA). The adhesion and migration abilities of osteoclast precursors and osteoclasts were determined by adhesion and migration assays, in vitro. Bone resorption was performed to measure osteoclast function. Cytoskeletal changes were assessed by F-actin ring formation. αvß3 integrin expression in osteoclasts was measured by flow cytometry. Western blotting and co-immunoprecipitation were performed to measure alterations in integrin/Pyk2/Src signaling pathway. RESULTS: Our results showed that blockade of ASIC1a using ASIC1a-siRNA inhibited acid-induced osteoclast precursor migration and adhesion, as well as osteoclast adhesion and bone resorption; we also demonstrated that inhibition of ASIC1a decreased the cell surface αvß3 integrin and ß3 protein expression. Moreover, blocking of ASIC1a inhibited acidosis-induced actin ring formation and reduced Pyk2 and Src phosphorylation in osteoclasts and also inhibited the acid-induced association of the αvß3 integrin/Src/Pyk2. CONCLUSION: Together, these results highlight a key functional role of ASIC1a/αvß3 integrin/Pyk2/Src signaling pathway in migration and adhesion of osteoclasts.

RESEARCH ARTICLE Molecular cloning and expression analysis of a matrix Gla protein gene in the spinyhead croaker, Collichthys lucidus.

The matrix Gla (gamma-carboxyglutamic acid-rich) protein (MGP), a vitamin K-dependent and Gla-containing protein, is a calcification inhibitor that mainly functions in tissue calcification and mineralization. In this study, we obtained the complete cDNA sequence of MGP from the spinyhead croaker (Collichthys lucidus), which we named Cl-MGP. Cl-MGP was 923 bp long with a 384-bp open reading fragment that encoded 127 amino acids. The predicted MGP protein sequence contained a 19-residue hydrophobic signal peptide, suggesting that it possesses secretory characteristics. The Gla domain and the invariant unit ErraEtCedyspC, which has been identified in all known vitamin K-dependent vertebrate proteins, were highly conserved in Cl-MGP, suggesting that it uses the same mechanism to function as the known proteins. An alignment analysis revealed that Cl-MGP had the highest identity with Larimichthys crocea (93%), which had lost five amino acid residues in the C-terminal. A quantitative real-time polymerase chain reaction revealed that Cl-MGP expression was highest in the gill, followed by the cholecyst and spleen, with almost no expression in the blood, muscle, or testes. The high Cl-MGP expression in the gill is similar to that observed in other fish species, but the relatively high expression found in the cholecyst and spleen is not seen in all species. Future studies should investigate the tissue distributions of both mRNA and proteins in different species, in order to understand the function and evolution of MGP in different species.

Investigation of JAKs/STAT-3 in lipopolysaccharide-induced intestinal epithelial cells.

Janus-activated kinase (JAKs)-signal transducer and activator of transcription 3 (STAT-3) signalling play critical roles in immunoregulation and immunopathology, which involve inflammatory responses and enteritis. JAK phosphorylates STAT-3 in response to stimulation by cytokines or growth factors, and then activates or represses the gene expression. STAT-3 is activated persistently in cancer cells and contributes to the malignant progression of various types of cancer and inflammation. To elucidate the different roles of JAKs in the activation of STAT-3, the lipopolysaccharide-induced primary intestinal epithelial cell (IEC) acute inflammatory model was established. Small interference RNAs (siRNAs) were then employed to attenuate the expression levels of JAKs. Real-time quantitative reverse transcription-polymerase chain reaction (PCR) (qRT-PCR) revealed that JAK mRNA levels were reduced efficiently by JAK-specific siRNAs. Under the IEC inflammatory model transfected with si-JAK, which equates to effective silencing, qRT-PCR and Western blot assays, suggested that knockdowns of JAK attenuated the JAK-induced down-regulation of STAT-3 at the mRNA or protein levels. In particular, JAK1 played a key role, which was consistent with the RNA-Seq results. Subsequently, the expression levels of proinflammatory cytokines interleukin (IL)-1ß and tumour necrosis factor (TNF)-α were down-regulated in the IEC inflammatory model transfected with si-JAK1. JAK1 appears as a direct activator for STAT-3, whereas treatments targeting JAK1 repressed STAT-3 sufficiently pathways in the IEC inflammatory model. Therefore, the control of JAK1 using siRNAs has the potential to be an effective strategy against enteritis.

Molecular cloning and expression analyses of RPS3a gene from mulberry under abiotic stresses and among different mulberry varieties.

A full-length cDNA sequence coding ribosomal protein S3a of mulberry tree, which we designated MmRPS3a (GenBank accession No. KR610331), was cloned based on mulberry expressed sequence tags. Sequence analysis showed that the MmRPS3a is 1089 bp long and contains a 80-bp 5'-UTR (untranslated region) and a 220-bp 3'-UTR. Its open reading frame consists of a 789-bp encoding 262 amino acids with a predicted molecular weight of 30.053 kDa and an isoelectric point of 9.84. Homology analysis revealed that MmRPS3a gene is highly conservative in mulberry and other species including Morus notabilis, Theobroma cacao, and Ricinus communis. Phylogenetic analysis based on MmRPS3a of other species showed that mulberry had a closer relationship with Prunus persica, Arabidopsis thaliana, Solanum tuberosum, Solanum lycopersicum, and Vitis vinifera. The results of quantitative PCR analysis showed that the transcriptional level of MmRPS3a mRNA changed significantly under the conditions of hypothermia, aridity, salt stress, and varieties of differing resistances.

Evaluation of Virtual Noncontrast Images Obtained from Dual-Energy CTA for Diagnosing Subarachnoid Hemorrhage.

BACKGROUND AND PURPOSE: The virtual noncontrast images generated with iodine subtraction from dual-energy CTA images are expected to replace the true noncontrast images for radiation-dose reduction. This study assessed the feasibility of virtual noncontrast images for diagnosing SAH. MATERIALS AND METHODS: Eighty-four patients with or without SAH underwent true noncontrast brain CT (the criterion standard for diagnosing SAH). Among them, 37 patients underwent an additional head dual-energy angiography, and the other patients underwent head and neck dual-energy angiography. Virtual noncontrast images were produced on a dedicated dual-energy postprocessing workstation and reconstructed in orientation and section width identical to those in true noncontrast images. The findings on the virtual noncontrast and true noncontrast images were compared at both the individual level and the lesion level. Image noise of the virtual noncontrast and true noncontrast images was also measured and compared. The volume CT dose index and dose-length product were recorded for the radiation-dose analysis. RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value of virtual noncontrast images at the individual level and the lesion level were 94.5%, 100%, 100%, 90.6% and 86.7%, 96.9%, 91.8%, 94.8%, respectively. The agreement in the diagnosis of SAH on true noncontrast and virtual noncontrast images reached 92.3% at the individual level and 85.1% at the lesion level. The virtual noncontrast images showed a higher image noise level. The volume CT dose index and dose-length product were obviously reduced without the true noncontrast brain CT scan. CONCLUSIONS: Virtual noncontrast images are a reliable tool for diagnosing SAH, with the advantage of reducing the radiation dose.

Expression of multidrug resistance 1 and multidrug resistance-related protein 1 in C57BL/6 mice treated with benzene.

ATP-binding cassette super family (ABC) proteins are considered key to oncology and pharmacology studies. We examined the effect of benzene on ABC pump protein levels in C57BL/6 mouse bone marrow mononuclear cells. After a 2-week gavage (200 mg/kg, 5 days per week), the number of peripheral leukocytes, lymphocytes and basophils dropped significantly; there was also a significant decrease in MDR1 and MRP1 gene expression. A significant reduction in expression of P-gp was found; however, there was no significant decrease in the expression of MRP1 and NF-κB p65. We conclude that regulation of membrane efflux transport protein could be a factor in benzene hematotoxicity.

Effective antitumor gene therapy delivered by polyethylenimine-conjugated stearic acid-g-chitosan oligosaccharide micelles.

Non-viral vesicle composing of low-molecular weight polyethylenimine-conjugated stearic acid-g-chitosan oligosaccharide (CSOSA-g-PEI) was synthesized for gene delivery and therapy. The synthesized CSOSA-g-PEI had good ion-buffer capabilities and DNA-binding capacity, which could form positively charged nano-sized particles (100-150 nm) with plasmid DNA; in vitro gene transfection tests demonstrated that CSOSA-g-PEI presented much lower cytotoxicity and corresponding transfection efficiency in comparison with Lipofectamine 2000 in both human cancer cells (Hela and MCF-7). The gene transfection of CSOSA-g-PEI/pDNA could be further enhanced in the presence of serum or by adding arginine during incubation of CSOSA-g-PEI micelles with plasmid DNA. The biodistribution experiments demonstrated CSOSA-g-PEI conjugate highly localized in the tumor tissue and indicated a persistently increased accumulation. In vivo antitumor activity results showed that CSOSA-g-PEI/plasmid pigment epithelium-derived factor formulation could effectively suppress the tumor growth (above 60% tumor inhibition) without systematic toxicity against animal body after intravenous injection.