Effect of superior cervical ganglion block on cardiac function and NLRP3 signaling pathway in a rat model of myocardial ischemia-reperfusion / 中华麻醉学杂志

Objective:To evaluate the effect of superior cervical ganglion block (SCGB) on cardiac function and nucleotide like receptor protein 3 (NLRP3) signaling pathway in a rat model of myocardial ischemia-reperfusion (I/R).Methods:Sixty healthy SPF male Sprague-Dawley rats, weighing 250-300 g, aged 2-3 months, were divided into 4 groups ( n=15 each) using a random number table method: sham operation group (sham group), myocardial I/R group (IR group), myocardial I/R + normal saline group (IR+ NS group), and myocardial I/R + SCGB group (IR+ SCGB group). Myocardial I/R model was developed by ligation of the left anterior descending branch of the coronary artery for 45 min followed by restoration of blood flow in anesthetized aninals. IR+ SCGB group received SCGB (0.25% ropivacaine 0.1 ml) at 10 min before reperfusion once a day for 2 consecutive weeks, while 0.9% sodium chloride was given instead of ropivacaine in IR+ NS group. Blood samples were collected at 24 h and 14 days of reperfusion for determination of serum concentrations of norepinephrine (NE), troponin T (TnT), tumor necrosis factor-alpha (TNF-α), interleukin-18 (IL-18) and IL-1β by enzyme-linked immunosorbent assay. Echocardiography was performed before ischemia and at 14 days of reperfusion, and left ventricular short axis shortening rate (FS), ejection fraction (EF), and cardiac output (CO) were measured. The rats were sacrificed at 14 days of reperfusion and the hearts were taken for determination of the contents of norepinephrine (NE) in myocardial tissues in the infarction area (by enzyme-linked immunosorbent assay), percentage of myocardial fibrosis area (by Masson staining), M1 macrophage marker CD68 + cell count in the infarction area (by immunohistochemical method), and expression of NLRP3 and gasdermin D (GSDMD) in myocardial tissues (by Western blot). Results:Compared with Sham group, the serum concentrations of TnT, TNF-α, IL-18 and IL-1β, percentage of myocardial fibrosis area, and NE levels in serum and myocardial tissues were significantly increased, the expression of NLRP3 and GSDMD in myocardial tissues was up-regulated, CD68 + cell count was increased, and EF, CO and FS were decreased in IR group ( P<0.05). Compared with IR group, the serum concentrations of TnT, TNF-α, IL-18 and IL-1β, percentage of myocardial fibrosis area, and NE levels in serum and myocardial tissues were significantly decreased, the expression of NLRP3 and GSDMD in myocardial tissues was down-regulated, CD68 + cell count was decreased, and EF, CO and FS were increased in IR+ SCGB group ( P<0.05), and no statistically significant changes were found in the parameters mentioned above in IR+ NS group ( P>0.05). Conclusions:SCGB can improve the cardiac function in a rat model of myocardial I/R, and the mechanism may be related to the inhibition of NLRP3 signaling pathway.

Relationship between inducible nitric oxide synthase and delayed encephalopathy in carbon monoxide poisoning / 中华急诊医学杂志

Objective:To observe the relationship between inducible carbon monoxide synthase (iNOS) and delayed encephalopathy after acute carbon monoxide poisoning (DEACMP), and explore its mechanism of action in DEACMP.Methods:This study was designed as prospective cohort study. Patients with acute carbon monoxide poisoning who met the diagnostic criteria and were admitted to Emergency Intensive Care Unit(EICU) of our hospital from June 2019 to June 2021 were selected as subjects. Patients were divided into the DEACMP group and non-DEACMP group according to the occurrence of DEACMP. Serum samples were collected on the first 24 h after admission and on day 7 and 14 after admission, and the serum nitric oxide (NO), neuronal nitric oxide synthase (nNOS), inducible carbon monoxide synthase (iNOS), and endothelial nitric oxide synthase (eNOS) level were measured by enzyme-linked immunosorbent assay. The generalized estimating equation was used to estimate the difference of NO, nNOS, iNOS and eNOS between DEACMP and non-DEACMP patients.Results:A total of 78 patients with carbon monoxide poisoning were included in our study finally, including 49 (62.82%) males and 29 (37.18%) females, with an average age of (53.96±14.95) years, 20 (25.64%) patients with DEACMP, and 1 (1.28%) death. Univariate analysis showed that patients with DEACMP had an average increase of 3 h (95% CI: 1.00, 5.00) in carbon monoxide exposure time and a 5-point decrease in GCS score (95% CI: 1.00, 6.00) than the patients without DEACMP, and the proportion of patients with severe carbon monoxide poisoning in the DEACMP group was higher than that of the non-DEACMP group (90.00% vs. 32.76%). According to the analysis of generalized estimation equation, on day 7 and 14 after admission, Compared with non-DEACMP patients, neither by performing unadjusted nor adjusted analysis with the iNOS of DEACMP patients was significantly higher than that in non-DEACMP patients regardless of whether exposure time, GCS score, coma time or severity of carbon monoxide poisoning were adjusted or not ( P <0.01 or P <0.05). Except for the level of nNOS in the GEE model adjusted with carbon monoxide exposure time, the levels of NO, nNOS and eNOS showed no significant difference between DEACMP and non-DEACMP patients ( P >0.05). Conclusions:The expression of iNOS level is increased in DEACMP patients, and its continuous expression may be involved in the pathogenesis of DEACMP.

Transferrin receptor is another receptor for SARS-CoV-2 entry

Angiotensin-converting enzyme 2 (ACE2) has been suggested as a receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) entry to cause coronavirus disease 2019 (COVID-19). However, no ACE2 inhibitors have shown definite beneficiaries for COVID-19 patients, applying the presence of another receptor for SARS-CoV-2 entry. Here we show that ACE2 knockout dose not completely block virus entry, while TfR directly interacts with virus Spike protein to mediate virus entry and SARS-CoV-2 can infect mice with over-expressed humanized transferrin receptor (TfR) and without humanized ACE2. TfR-virus co-localization is found both on the membranes and in the cytoplasma, suggesting SARS-CoV-2 transporting by TfR, the iron-transporting receptor shuttling between cell membranes and cytoplasma. Interfering TfR-Spike interaction blocks virus entry to exert significant anti-viral effects. Anti-TfR antibody (EC50 ~16.6 nM) shows promising anti-viral effects in mouse model. Collectively, this report indicates that TfR is another receptor for SARS-CoV-2 entry and a promising anti-COVID-19 target.

Susceptibility of tree shrew to SARS-CoV-2 infection

Since SARS-CoV-2 became a pandemic event in the world, it has not only caused huge economic losses, but also a serious threat to global public health. Many scientific questions about SARS-CoV-2 and COVID-19 were raised and urgently need to be answered, including the susceptibility of animals to SARS-CoV-2 infection. Here we tested whether tree shrew, an emerging experimental animal domesticated from wild animal, is susceptible to SARS-CoV-2 infection. No clinical signs were observed in SARS-CoV-2 inoculated tree shrews during this experiment except the increasing body temperature (above 39{degrees} C) particular in female animals during infection. Low levels of virus shedding and replication in tissues occurred in all three age groups, each of which showed his own characteristics. Histopathological examine revealed that pulmonary abnormalities were mild but the main changes although slight lesions were also observed in other tissues. In summary, tree shrew is not susceptible to SARS-CoV-2 infection and may not be a suitable animal for COVID-19 related researches.

Comparison of SARS-CoV-2 infections among 3 species of non-human primates

COVID-19, caused by SARS-CoV-2 infection, has recently been announced as a pandemic all over the world. Plenty of diagnostic, preventive and therapeutic knowledges have been enriched from clinical studies since December 2019. However, animal models, particularly non-human primate models, are urgently needed for critical questions that could not be answered in clinical patients, evaluations of anti-viral drugs and vaccines. In this study, two families of non-human primates, Old world monkeys (12 Macaca mulatta, 6 Macaca fascicularis) and New world monkeys (6 Callithrix jacchus), were experimentally inoculated with SARS-CoV-2. Clinical signs were recorded. Samples were collected for analysis of viral shedding, viremia and histopathological examination. Increased body temperature was observed in 100% (12/12) M. mulatta, 33.3% (2/6) M. fascicularis and none (0/6) of C. jacchus post inoculation of SARS-CoV-2. All of M. mulatta and M. fascicularis showed chest radiographic abnormality. Viral genomes were detected in nasal swabs, throat swabs, anal swabs and blood from all 3 species of monkeys. Viral shedding from upper respiratory samples reached the peak between day 6 and day 8 post inoculation. From necropsied M. mulatta and M. fascicularis, the tissues showing virus positive were mainly lung, weasand, bronchus and spleen. No viral genome was seen in any of tissues from 2 necropsied C. jacchus. Severe gross lesions and histopathological changes were observed in lung, heart and stomach of SARS-CoV-2 infected animals. In summary, we have established a NHP model for COVID-19, which could be used to evaluate drugs and vaccines, and investigate viral pathogenesis. M. mulatta is the most susceptible to SARS-CoV-2 infection, followed by M. fascicularis and C. jacchus. One Sentence SummaryM. mulatta is the most susceptible to SARS-CoV-2 infection as compared to M. fascicularis and C. jacchus.

The Pathogenicity of 2019 Novel Coronavirus in hACE2 Transgenic Mice

Severe acute respiratory syndrome CoV-2 (SARS-CoV-2) caused the Corona Virus Disease 2019 (COVID-19) cases in China has become a public health emergency of international concern (PHEIC). Based on angiotensin converting enzyme 2 (ACE2) as cell entry receptor of SARS-CoV, we used the hACE2 transgenic mice infected with SARS-CoV-2 to study the pathogenicity of the virus. Weight loss and virus replication in lung were observed in hACE2 mice infected with SARS-CoV-2. The typical histopathology was interstitial pneumonia with infiltration of significant lymphocytes and monocytes in alveolar interstitium, and accumulation of macrophages in alveolar cavities. Viral antigens were observed in the bronchial epithelial cells, alveolar macrophages and alveolar epithelia. The phenomenon was not found in wild type mice with SARS-CoV-2 infection. The pathogenicity of SARS-CoV-2 in hACE2 mice was clarified and the Kochs postulates were fulfilled as well, and the mouse model may facilitate the development of therapeutics and vaccines against SARS-CoV-2.

Monitoring results of human brucellosis from 2013 to 2017 in Harbin / 中华地方病学杂志

Objective To find out the epidemic characteristics of brucellosis in Harbin and provide scientific evidences for development of countermeasures.Methods The brucellosis surveillance data were collected from the "National Diseases Surveillance Information Management System" and the municipal surveillance results from 2013 to 2017 in Harbin;the place,time and population distribution characteristics of brucellosis were analyzed by descriptive epidemiological methods.Results A total of 2 909 cases of brucellosis were reported in Harbin from 2013 to 2017,and the incidence of brucellosis declined from 5.98 per 100 000 to 4.53 per 100 000,the epidemic situation was mainly sporadic,and an outbreak caused by a live Brucella vaccine (A19 strain) was reported in 2017;all eighteen districts (counties or cities) in Harbin had reported epidemic in the past five years,Shuangcheng,Yilan,Binxian and Bayan had a large number of cases,accounted for 53.76％ (1 564/2 909) of the total number of patients in Harbin;the time of onset focused on March to July,which accounted for 57.17％ (1 663/2 909) of annual incidence;age distribution,mainly young adults aged 30 to 59,accounted for 72.57％ (2 111/2 909);gender distribution predominandy male,accounted for 75.42％ (2 194/2 909);and occupational distribution predominantly farmers,accounted for 86.28％ (2 510/2 909).In the municipal surveillance stations from 2013 to 2017,7 005 cases were surveyed,of which 2 141 cases received serological test,the positive rate was 3.32％ (71/2 141),except 2016,the serum positive rate was decreasing year by year (x2 =13.927,P ＜ 0.05),and the monitoring results of municipal monitoring stations can better reflect the epidemic trend.Conclusions The incidence of brucellosis in Harbin is decreasing year by year.However,the outbreak caused by the new vaccines should be given high attention and we should strengthen prevention and control of the disease.

A comparative proteomic analysis for adventitious root formation in lotus root (Nelumbo nucifera Gaertn).

Adventitious roots (ARs) directly affect lotus seedling growth and product quality because principal root is not well developed. However, the details of AR formation at the molecular level have not been determined in lotus. Therefore, three stages were chosen to identify the change of proteins abundant during rhizome formation, using isobaric tags for relative and absolute quantization coupled with liquid chromatography-tandem mass spectrometry to gain insight into the molecular mechanisms involved in AR formation. We totally obtained 323,375 spectra during AR formation. After filtering to eliminate low-scoring spectra, 66,943 spectra, including 53,106 unique spectra, were identified. These unique spectra matched 28,905 peptides, including 24,992 unique peptides, which were assembled into 6686 proteins. In the C0/C1 and C1/C2 stages, 66 and 32 proteins showed enhanced abundance, and 173 and 73 proteins showed decreased abundance, respectively. Seventeen important AR formation-related proteins from the three stages were identified, and the expressions of nine genes from the above-identified proteins were assessed by qRT-PCR. This article provides a comprehensive understanding of the changes in metabolism during AR formation, and is helpful to accelerate the progress of breeding in fulture in lotus root.