A new species and a new record of Phlomoides (Lamiaceae) from Xizang, China.

Phlomoidesbomiensis, a new species in Bomi County, Xizang, China, was described and illustrated. In addition, Phlomoideslongidentata, previously only known from Nepal and Bhutan, is newly recorded from Dingri County, Xizang, China. The phylogenetic placement of both species within the genus was analysed using nine plastid DNA markers (atpB-rbcL, psbA-trnH, rpl16, rpl32-trnL, rps16, trnK, trnL-trnF, trnS-trnG, trnT-trnL). Both species have brown-black trichomes inside the upper corolla lip and nested within the same subclade of Clade II. A diagnostic key to the Phlomoides species belonging to this subclade is provided.

Clinical spectrum, over 12-year follow-up and experience of SGLT2 inhibitors treatment on patients with glycogen storage disease type Ib: a single-center retrospective study.

BACKGROUND: Glycogen storage disease type Ib (GSD Ib) is a rare disorder characterized by impaired glucose homeostasis caused by mutations in the SLC37A4 gene. It is a severe inherited metabolic disease associated with hypoglycemia, hyperlipidemia, lactic acidosis, hepatomegaly, and neutropenia. Traditional treatment consists of feeding raw cornstarch which can help to adjust energy metabolism but has no positive effect on neutropenia, which is fatal for these patients. Recently, the pathophysiologic mechanism of the neutrophil dysfunction and neutropenia in GSD Ib has been found, and the treatment with the SGLT2 inhibitor empaglifozin is now well established. In 2020, SGLT2 inhibitor empagliflozin started to be used as a promising efficient remover of 1,5AG6P in neutrophil of GSD Ib patients worldwide. However, it is necessary to consider long-term utility and safety of a novel treatment. RESULTS: In this study, we retrospectively examined the clinical manifestations, biochemical examination results, genotypes, long-term outcomes and follow-up of thirty-five GSD Ib children who visited our department since 2009. Fourteen patients among them underwent empagliflozin treatment since 2020. This study is the largest cohort of pediatric GSD Ib patients in China as well as the largest cohort of pediatric GSD Ib patients treated with empagliflozin in a single center to date. The study also discussed the experience of long-term management on pediatric GSD Ib patients. CONCLUSION: Empagliflozin treatment for pediatric GSD Ib patients is efficient and safe. Increase of urine glucose is a signal for pharmaceutical effect, however attention to urinary infection and hypoglycemia is suggested.

A new metal ion chelator attenuates human tau accumulation-induced neurodegeneration and memory deficits in mice.

Neuronal neurofibrillary tangles containing Tau hyperphosphorylation proteins are a typical pathological marker of Alzheimer's disease (AD). The level of tangles in neurons correlates positively with severe dementia. However, how Tau induces cognitive dysfunction is still unknown, which leads to a lack of effective treatments for AD. Metal ions deposition occurs with tangles in AD brain autopsy. Reduced metal ion can improve the pathology of AD. To explore whether abnormally phosphorylated Tau causes metal ion deposition, we overexpressed human full-length Tau (hTau) in the hippocampal CA3 area of mice and primary cultured hippocampal neurons (CPHN) and found that Tau accumulation induced iron deposition and activated calcineurin (CaN), which dephosphorylates glycogen synthase kinase 3 beta (GSK3ß), mediating Tau hyperphosphorylation. Simultaneous activation of CaN dephosphorylates cyclic-AMP response binding protein (CREB), leading to synaptic deficits and memory impairment, as shown in our previous study; this seems to be a vicious cycle exacerbating tauopathy. In the current study, we developed a new metal ion chelator that displayed a significant inhibitory effect on Tau phosphorylation and memory impairment by chelating iron ions in vivo and in vitro. These findings provide new insight into the mechanism of memory impairment induced by Tau accumulation and develop a novel potential treatment for tauopathy in AD.

Protective effect of vitamin B6 against doxorubicin-induced cardiotoxicity by modulating NHE1 expression.

Doxorubicin (DOX) has been used to treat various types of cancer, but its application is limited due to its heart toxicity as well as other drawbacks. Chronic inhibition of Na+ /H+ exchanger (NHE1) reduces heart failure and reduces the production of reactive oxygen species (ROS); vitamin B6 (VitB6 ) has been demonstrated to have a crucial role in antioxidant mechanism. So, this study was designed to explore the effect of VitB6 supplement on the DOX-induced cardiotoxicity and to imply whether NHE1 is involved. Ultrasonic cardiogram analysis revealed that VitB6 supplement could alleviate DOX-induced cardiotoxicity; hematoxylin and eosin (HE) and Masson's staining further confirmed this effect. Furthermore, VitB6 supplement exhibited significant antioxidative stress and antiapoptosis effect, which was evidenced by decreased serum malondialdehyde (MDA) content and increased serum superoxide dismutase (SOD) content, and decreased Bcl-2-associated X protein/B-cell lymphoma-2 ratio, respectively. Collectively, VitB6 supplement may exert antioxidative and antiapoptosis effects to improve cardiac function by decreasing NHE1 expression and improve DOX-induced cardiotoxicity.

Recent innovations in microplastics and nanoplastics removal by coagulation technique: Implementations, knowledge gaps and prospects.

Recently, microplastics (MPs) and nanoplastics (NPs) contamination is a worldwide problem owing to the immense usage of plastic commodities. Thus, the environmental risks by MPs and NPs demand the application of innovative, efficient, and sustainable technologies to control the pollution of plastic particles. Regarding this, numerous technologies, including adsorption, coagulation, filtration, bioremediation, chemical precipitation, and photocatalysis, have been engaged to eradicate MPs and NPs from contaminated waters. However, the coagulation technique is getting much attention owing to its simplicity, higher removal performance, low carbon footprint, and low operational and maintenance cost. Therefore, this paper has been designed to critically summarize the recent innovations on the application of coagulation process to eradicate MPs and NPs from both synthetic and real sewage. More importantly, the effect of pertinent factors, including characteristics of coagulants, MPs/NPs, and environmental medium on the elimination performances and mechanisms of MPs/NPs have been critically investigated. Further, the potential of coagulation technology in eliminating MPs and NPs from real sewage has been critically elucidated for the first time, for better execution of this technique at commercial levels. Finally, this critical review also presents current research gaps and future outlooks for the improvement of coagulation process for eradicating MPs and NPs from water and real sewage. Overall, the current review will offer valuable knowledge to scientists in selecting a suitable technique for controlling plastic pollution.

Amorphous selenium inhibits oxidative stress injury of neurons in vascular dementia rats by activating NMDAR pathway.

Vascular dementia (VD) is one of the most common causes of dementia, taking account for about 20% of all cases. Although studies have found that selenium supplementation can improve the cognitive ability of Alzheimer's patients, there is currently no research on the cognitive impairment caused by VD. This study aimed to investigate the role and mechanism of Amorphous selenium nanodots (A SeNDs) in the prevention of VD. The bilateral common carotid artery occlusion (BCCAO) method was used to establish a VD model. The neuroprotective effect of A SeNDs was evaluated by Morris water maze, Transcranial Doppler TCD, hematoxylin-eosin (HE) staining, Neuron-specific nuclear protein (Neu N) staining and Golgi staining. Detect the expression levels of oxidative stress and Calcium-calmodulin dependent protein kinase II (CaMK II), N-methyl-D-aspartate receptor subunit NR2A, and postsynaptic dense protein 95 (PSD95). Finally, measure the concentration of calcium ions in neuronal cells. The results showed that A SeNDs could significantly improve the learning and memory ability of VD rats, restore the posterior arterial blood flow of the brain, improve the neuronal morphology and dendritic remodeling of pyramidal cells in hippocampal CA1 area, reduce the level of oxidative stress in VD rats, increase the expression of NR2A, PSD95, CaMK II proteins and reduce intracellular calcium ion concentration, but the addition of selective NR2A antagonist NVP-AAMO77 eliminated these benefits. It suggests that A SeNDs may improve cognitive dysfunction in vascular dementia rats by regulating the NMDAR pathway.

Seed morphology of Hypericum (Hypericaceae) in China and its taxonomic significance.

The seed morphology of 40 taxa within the genus Hypericum (Hypericaceae) from China, representing 9 sections of the genus, was examined using both Light and Scanning Electron Microscopy to evaluate the taxonomic relevance of macro- and micro-morphological features. Details articulating variation in seed size, color, shape, appendages, and seed coat ornamentation are described, illustrated, and compared, and their taxonomic importance is discussed. Seeds were generally brown in color and cylindric-ellipsoid to prolonged cylindric in shape. Seed size displayed wide variation, ranging from 0.37-1.91 mm in length and 0.12-0.75 mm in width. Seed appendages were observed as a characteristic morphological feature. Seed surface ornamentation has high phenotypic plasticity, and four types (reticulate, foveolate, papillose, and ribbed) can be recognized. In general, seed color and shape have limited taxonomic significance. However, some other features represent informative characters that can be used efficiently in distinguishing the studied taxa at the section and/or species levels. The findings illustrate that considerable taxonomic knowledge can be obtained by investigating the seed features of Hypericum, and the use of Scanning Electron Microscopy can reveal inconspicuous morphological affinities among species and play a role in taxonomic and systematic studies of the genus Hypericum. RESEARCH HIGHLIGHTS: Macro- and micro-morphological features of seeds of 40 Hypericum taxa from China were examined using Light and Scanning Electron Microscopy, providing the first broad study regarding seed morphology for Hypericum from China. Details and variations of seed size, shape, color, surface ornamentation, and appendages are fully presented. Seed features and their variation have important taxonomic significance at the section and/or species levels within Hypericum.

Design and characteristic research of smart rod based on optical fiber grating for strain monitoring of power transmission tower.

The safety of the power transmission towers is the basis for the reliable operation of the power grid. Real-time monitoring of the strain of the key rods of the power transmission tower can reflect the safety status of the power transmission tower. In this paper, a smart rod equipped with fiber Bragg grating with strain sensitivity enhanced structure is proposed to detect the strain of key rods of large-span power transmission towers on the southeast coast of the Yangtze River. The smart rod can be connected with the power transmission tower rod through the foot nails and the force on the tower can be transformed effectively. This structure has the advantages of convenient installation and no damage to the power transmission tower. Prestress can be applied to fiber Bragg grating equipped in the smart rod through the prestressed sleeve and can be continuously and accurately adjusted, sensitivity of the fiber Bragg grating was enhanced by strain sensitivity enhanced structure. The relationship between force and strain of fiber Bragg grating installed in the smart rod was analyzed by ANSYS software. Experimental results show that the sensitivity of the fiber Bragg grating strain sensor in the smart rod is 13 times that of the conventional structure fiber Bragg grating strain sensor, and the linearity between the fiber Bragg grating wavelength change and force is as high as 0.999. Temperature compensation was realized through temperature measurement fiber Bragg grating installed in the smart rod. This structure can be used to measure the strain of a large-span power transmission tower from 0 to 2000 µÎµ with an accuracy of 0.1 µÎµ with good repeatability.

Diagnostic ultrasound-mediated microbubble cavitation dose-dependently improves diabetic cardiomyopathy through angiogenesis.

Ultrasound-mediated microbubble cavitation (UMMC) induces therapeutic angiogenesis to treat ischemic diseases. This study aimed to investigate whether diagnostic UMMC alleviates diabetic cardiomyopathy (DCM) and, if so, through which mechanisms. DCM model was established by injecting streptozocin into rats to induce hyperglycemia, followed by a high-fat diet. The combined therapy of cation microbubble with low-intensity diagnostic ultrasound (frequency = 4 MHz), with a pulse frequency of 20 Hz and pulse length (PL) of 8, 18, 26, or 36 cycles, was given to rats twice a week for 8 consecutive weeks. Diagnostic UMMC therapy with PL at 8, 18, and 26 cycles, but not 36 cycles, dramatically prevented myocardial fibrosis, improved heart functions, and increased angiogenesis, accompanied by increased levels of PI3K, Akt, and eNOS proteins in the DCM model of rats. In cultured endothelial cells, low-intensity UMMC treatment (PL = 3 cycles, sound pressure level = 50%, mechanical index = 0.82) increased cell viability and activated PI3K-Akt-eNOS signaling. The combination of diagnostic ultrasound with microbubble destruction dose-dependently promoted angiogenesis, thus improving heart function through PI3K-Akt-eNOS signaling in diabetes. Accordingly, diagnostic UMMC therapy should be considered to protect the heart in patients with diabetes.

Microbial-induced calcium carbonate precipitation: Influencing factors, nucleation pathways, and application in waste water remediation.

Microbial-induced calcium carbonate precipitation (MICP) is a technique that uses the metabolic action of microorganisms to produce CO32- which combines with free Ca2+ to form CaCO3 precipitation. It has gained widespread attention in water treatment, aimed with the advantages of simultaneous removal of multiple pollutants, environmental protection, and ecological sustainability. This article reviewed the mechanism of MICP at both intra- and extra-cellular levels. It summarized the parameters affecting the MICP process in terms of bacterial concentration, ambient temperature, etc. The current status of MICP application in practical engineering is discussed. Based on this, the current technical difficulties faced in the use of MICP technology were outlined, and future research directions for MICP technology were highlighted. This review helps to improve the design of existing water treatment facilities for the simultaneous removal of multiple pollutants using the MICP and provides theoretical reference and innovative thinking for related research.

Citronellal Attenuates Oxidative Stress-Induced Mitochondrial Damage through TRPM2/NHE1 Pathway and Effectively Inhibits Endothelial Dysfunction in Type 2 Diabetes Mellitus.

In type 2 diabetes mellitus (T2DM), oxidative stress induces endothelial dysfunction (ED), which is closely related to the formation of atherosclerosis. However, there are few effective drugs to prevent and cure it. Citronellal (CT) is an aromatic active substance extracted from citronella plants. Recently, CT has been shown to prevent ED, but the underlying mechanism remains unclear. The purpose of this study was to investigate whether CT ameliorated T2DM-induced ED by inhibiting the TRPM2/NHE1 signal pathway. Transient receptor potential channel M2 (TRPM2) is a Ca2+-permeable cation channel activated by oxidative stress, which damages endothelial cell barrier function and further leads to ED or atherosclerosis in T2DM. The Na+/H+ exchanger 1 (NHE1), a transmembrane protein, also plays an important role in ED. Whether TRPM2 and NHE1 are involved in the mechanism of CT improving ED in T2DM still needs further study. Through the evaluations of ophthalmoscope, HE and Oil red staining, vascular function, oxidative stress level, and mitochondrial membrane potential evaluation, we observed that CT not only reduced the formation of lipid deposition but also inhibited ED and suppressed oxidative stress-induced mitochondrial damage in vasculature of T2DM rats. The expressions of NHE1 and TRPM2 was up-regulated in the carotid vessels of T2DM rats; NHE1 expression was also upregulated in endothelial cells with overexpression of TRPM2, but CT reversed the up-regulation of NHE1 in vivo and in vitro. In contrast, CT had no inhibitory effect on the expression of NHE1 in TRPM2 knockout mice. Our study show that CT suppressed the expression of NHE1 and TPRM2, alleviated oxidative stress-induced mitochondrial damage, and imposed a protective effect on ED in T2DM rats.

Shunxin decoction improves diastolic function in rats with heart failure with preserved ejection fraction induced by abdominal aorta constriction through cyclic guanosine monophosphate-dependent protein kinase Signaling Pathway.

OBJECTIVE: To determine whether Shunxin decoction improves diastolic function in rats with heart failure with preserved ejection fraction (HFpEF) by regulating the cyclic guanosine monophosphate-dependent protein kinase (cGMP-PKG) signaling pathway. METHODS: Except for control group 8 and sham surgery group 8, the remaining 32 male Sprague-Dawlay rats were developed into HFpEF rat models using the abdominal aorta constriction method. These rats in the HFpEF model were randomly divided into the model group, the Shunxin high-dose group, the Shunxin low-dose group, and the Qiliqiangxin capsule group. The three groups received high-dose Shunxin decoction, low-dose Shunxin decoction, and Qiliqiangxin capsule by gavage, respectively, for 14 d. After the intervention, the diastolic function of each rat was evaluated by testing E/A, heart index, hematoxylin-eosin staining, Masson, myocardial ultrastructure, and N-terminal pro-brain natriuretic peptide (NT-proBNP). The Bioinformatics Analysis Tool for Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM) software was used to predict targets for which Shunxin decoction acts on the cGMP-PKG pathway. Natriuretic peptide receptor A (NPRA) and guanylate cyclase (GC) were detected by immunohistochemistry, and eNOS, phosphodiesterase 5A (PDE5A), and cGMP-dependent protein kinase 1(PKG I) were determined by Western blotting. RESULTS: Compared to the model group, the thickness of the interventricular septum at the end of diastole (IVSd) and the thickness of the posterior wall at the end of diastole (PWd) of the Shunxin decoction high-dose group, Shunxin decoction low-dose group, and Qiliqiangxin capsule group were all significantly reduced ( < 0.01). Furthermore, Shunxin decoction high-dose group E/A value was decreased ( < 0.01). Compared to the model group, the expression of NPRA and GC increased in the Shunxin decoction low-dose group and the Qiliqiangxin capsule group ( < 0.01). Compared to the model group, the expressions of eNOS and PKG I increased ( < 0.05) in the Shunxin decoction high-dose group. The expression of PDE5A expression decreased in the myocardium of the Shunxin decoction high-dose group, Shunxin decoction low-dose group, and Qiliqiangxin capsule group compared to the model group ( < 0.01). CONCLUSIONS: Shunxin decoction can improve diastolic function in rats with HFpEF. It increases the expression of NPRA, GC, and eNOS in the myocardial cell cGMP-PKG signaling pathway, upregulates cGMP expression, decreases PDE5A expression to reduce the cGMP degradation. Thus, the cGMP continually stimulates PKG I, reversing myocardial hypertrophy and improving myocardial compliance in HFpEF rats.

Sesquiterpene Lactams and Lactones With Antioxidant Potentials From Atractylodes macrocephala Discovered by Molecular Networking Strategy.

Atractylodes macrocephala rhizome (called Bái-zhú in China) has a long history as a functional food and herbal medicine in East Asia, especially China. Sesquiterpenoids are one of the main active compounds of Atractylodes macrocephala rhizome. This study aimed to explore the unknown sesquiterpenoids of A. macrocephala rhizome using a molecular networking strategy. Two new nitrogen-containing sesquiterpenoids, atractylenolactam A (1) and atractylenolactam B (2), and 2 new sesquiterpene lactones, 8-methoxy-atractylenolide V (6) and 15-acetoxyl atractylenolide III (7), along with 12 known analogs (3-5 and 8-16) were discovered and isolated. All the structures were assigned based on detailed spectroscopic analyses. The absolute configurations of 1, 2, 6, and 7 were established by time-dependent density functional theory ECD (TDDFT-ECD) calculations. All these compounds had different degrees of concentration-dependent activating effects on nuclear-factor-E2-related factor-2 (Nrf2).

Genetic Characteristics of Porcine Hemagglutinating Encephalomyelitis Coronavirus: Identification of Naturally Occurring Mutations Between 1970 and 2015.

Porcine hemagglutinating encephalomyelitis virus (PHEV) is a Betacoronavirus characterized by neurological symptoms and a worldwide prevalence. Although PHEV is one of the earliest discovered porcine coronaviruses, it remains poorly studied. The full-length genome of the earliest PHEV strain collected in 1970 in the United States (PHEV/67 N/US/1970) was determined in October 2020. Using this virus as a prototype, we comparatively analyzed all available PHEV full-length sequences during 1970-2015. In phylogenetic trees based on PHEV full-length or spike glycoprotein open reading frame genomic sequences, PHEV/67 N/US/1970 was sorted into a clade different from that of viruses isolated in the United States in 2015. Intriguingly, United States and Belgium viruses isolated in 2015 and 2005, respectively, revealed multiple deletion mutation patterns compared to the strain PHEV/67 N/US/1970, leading to a truncated or a non-functional NS2A coding region. In addition, the genomic similarity analysis showed a hypervariability of the spike glycoprotein coding region, which can affect at least eight potential linear B cell epitopes located in the spike glycoprotein. This report indicates that PHEVs in the United States underwent a significant genetic drift, which might influence PHEV surveillance in other countries.

[New eudesmane sesquiterpenoids from Atractylodis Macrocephalae Rhizoma and their inhibitory activities against SREBPs].

Three sesquiterpenoids were isolated and purified from the 95% ethanol extract of Atractylodis Macrocephalae Rhizoma by column chromatography on silica gel, Sephadex LH-20, ODS, and high-performance liquid chromatography(HPLC). Their chemical structures were identified on the basis of spectroscopic analysis and physiochemical properties as(7Z)-8ß,13-diacetoxy-eudesma-4(15),7(11)-diene(1), 7-oxo-7,8-secoeudesma-4(15),11-dien-8-oic acid(2), and guai-10(14)-en-11-ol(3). Compounds 1 and 2 are new compounds and compound 3 was obtained from Compositae family for the first time. Compounds 1, 2, and 3 showed weak inhibitory activities against sterol regulatory element-binding proteins(SREBPs).

Two new sesquiterpenes from the rhizomes of Atractylodes macrocephala and their biological activities.

Two new sesquiterpenes, named selina-4(14),7,11-trien-9-ol (1) and selina-4(14),11-dien-7-ol (2), along with two known compounds were isolated from rhizomes of Atractylodes macrocephala Koidz. All structures were assigned on the basis of detailed spectroscopic analyses. The absolute configuration of 1 was established by TDDFT-ECD calculations. Compound 1 was found to moderately inhibit LSD1 activity with IC50 value of 34.0 µM. Compounds 1 and 4 exhibited a regulate effect on Keap1-Nrf2-ARE pathway.[Formula: see text].

[Effect of internal heat-type acupuncture needle on the expression of osteoprotegerin, receptor activator of NF-κB ligand and receptor activator of NF-κB of subchondral bone in knee osteoarthritis rabbits].

OBJECTIVE: To investigate the effect of internal heat-type acupuncture needle on the expression of osteoprotegerin (OPG), receptor activator of NF-κB ligand (RANKL), and receptor activator of NF-κB (RANK) in knee osteoarthritis (KOA) rabbits, so as to explore its mechanisms in relieving KOA. METHODS: Thirty New Zealand rabbits were randomly divided into control, model and treatment groups, with 10 rabbits in each group. The KOA model was established by using Hulth method. The rabbits of the treatment group received internal heat-type acupuncture needles (42 ℃) on the left hind limb 20 min, once a week for 4 weeks. The behavioral scores were assessed according to the pain severity, gait, joint motion range and articular swelling severity in reference to the modified Lequesne's methods. Toluidine Blue staining was performed to observe the structure of the subchondral bone and to analyze the difference of morphometric parameters. The protein and mRNA expressions of OPG, RANKL and RANK were detected by Western blot and real-time PCR, respectively. RESULTS: Compared with the control group, the Lequesne total score, the separation degree of trabecular bone, the protein and mRNA expressions of RANKL and RANK in subchondral bone tissues were significantly increased in the model group, while the percentage of trabecular bone area, number of trabecular bone, the expression of OPG protein and mRNA were decreased (P<0.05, P<0.01). The above indexes were all reversed in the treatment group relevant to those of the model group (P<0.05). CONCLUSION: The internal heat-type acupuncture needle therapy can improve the motor function of rabbits with KOA, which may be related to its effects in up-regulating the expression of OPG and down-regulating the RANKL and RANK in subchondral bone tissue.

The Characteristics of Spike Glycoprotein Gene of Swine Acute Diarrhea Syndrome Coronavirus Strain CH/FJWT/2018 Isolated in China.

Swine acute diarrhea syndrome (SADS) is a highly contagious infectious disease characterized by acute vomiting and watery diarrhea in neonatal piglets. The causative agent for SADS is the swine acute diarrhea syndrome coronavirus (SADS-CoV), an alphacoronavirus in the family Coronaviridae. Currently, SADS-CoV was identified only in Guangdong and Fujian provinces of China, not in any other regions or countries in the world. To explore the genetic diversity of SADS-CoV isolates, herein we comparatively analyzed 44 full-length genomes of viruses isolated in Guangdong and Fujian provinces during 2017-2019. The spike glycoprotein gene of SADS-CoV strain CH/FJWT/2018 isolated in Fujian province is distinct from that of other viral isolates in either spike glycoprotein gene-based phylogenetic analysis or whole genome-based gene similarity analysis. Moreover, at least 7 predicted linear B cell epitopes in the spike glycoprotein of CH/FJWT/2018 would be affected by amino acid variations when compared with a representative virus isolated in Guangdong province. The spike glycoprotein of coronaviruses determines viral host range and tissue tropism during virus infection via specific interactions with the cellular receptor and also plays critical roles in eliciting the production of neutralizing antibodies. Since SADS-CoVs have a broad cell tropism, the results in this report further emphasize that the spike glycoprotein gene is a pivotal target in the surveillance of SADS-CoV.

The spike glycoprotein genes of porcine epidemic diarrhea viruses isolated in China.

The porcine epidemic diarrhea virus (PEDV) causes a highly contagious disease in pigs, which is one of the most devastating viral diseases of swine in the world. In China, PEDV was first confirmed in 1984 and PEDV infections occurred sporadically from 1984 to early 2010. From late 2010 until present, PEDV infections have swept every province or region in China. In this study, we analyzed a total of 186 full-length spike genes and deduced proteins of all available complete genomes of PEDVs isolated in China during 2007-2019. A total of 28 potential recombination events were identified in the spike genes of PEDVs in China. Spike gene recombination not only expanded the genetic diversity of PEDVs in the GII genogroup, but also resulted in the emergence of a new evolutional branch GI-c during 2016-2018. In addition, comparative analysis of spike proteins between GI-a prototype virulent CV777 and GII strain AJ1102 reveals that the amino acid variations could affect 20 potential linear B cell epitopes, demonstrating a dramatic antigen drift in the spike protein. These results provide a thorough view of the information about the genetic and antigenic diversity of PEDVs circulating in China and therefore could benefit the development of suitable strategies for disease control.

Genetic drift of MERS-CoV in Saudi Arabia during 2012-2019.

Middle East respiratory syndrome (MERS) is caused by MERS-CoV that infects both human and camel. Camel is supposed to be the natural reservoir for human infection while the sources for most of the primary human infection cases are still not known. We identified two conserved pyrimidine nucleotides that flank UAAU element in MERS-CoV 5'-UTR. These conserved pyrimidine nucleotides distinguish MERS-CoVs into 3 types, that is, UUAAUU, CUAAUU and CUAAUC (referred to as U----U, C----U, and C----C types, respectively). Human MERS-CoV displays a genetic drift from U----U, C----U, to C----C from 2012 to 2019. Camel virus displays a genetic drift from U----U to C----U with a time lag when compared with human virus. The discrepancy in genetic drift seems not to support the notion that camel serves as the only natural reservoir for human infection.