Objective To investigate the titer stability of the harvest solution of severe acute respiratory syndrome coronavirus2(SARS-CoV-2)at 2 ～ 8 ℃ and the inactivation effect of β-propiolactone inactivator on the virus.Methods Three batches of SARS-CoV-2 harvest solution(batch numbers:202111001,202111002 and 202111003)were stored at 2 ～ 8 ℃ for 12 d and sampled every 3 d(0,3,6,9 and 12 d)for detection of the titers by Karber method;Three batches of virus harvest solution equilibrated overnight at 2 ～ 8 ℃ were inactivated by adding β-propiolactone at a volume fraction of 1∶4 000 and detected for the titers at different inactivation time points(0,0.5,1,1.5,2,3,4,8,16 and 24 h),of which samples inactivated for 8,16 and 24 h were taken for inactivation verification,and samples inactivated for 24 h were observed by transmission electron microscope.Results The titers of SARS-CoV-2 decreased with the prolongation of storage time at 2 ～8 ℃,which showed no obvious decrease during 0 ～ 3 d,while decreased from the initial 7.75,6 and 7.5 lgCCID_(50)/mL to5.75,4.625 and 6.25 lgCCID_(50)/mL on day 12,indicating that the virus activity showed a gradual decrease trend at 2 ～8 ℃；With the inactivation time,the virus titer decreased continuously and could not be detected after inactivation for 3 h.Transmission electron microscope observation showed that the inactivated virus particles were intact and the spike protein was evenly distributed.Conclusion The virulence of SARS-CoV-2 stored at 2 ～ 8 ℃ was unstable,so the subsequent inactivation and purification process should be carried out as soon as possible;The titer of virus could not be detected after3 h of inactivation,which provided a reference for the determination of the inactivation process.

OBJECTIVETo observe the effects of Panax notoginsenoside (PNS) on tumor necrosis factor-alpha (TNF-alpha) and matrix metalloproteinases-2 (MMP-2) expressions in rats with post-myocardial infarction ventricular remodeling and explore the mechanism.

METHODSRat models of acute infarction ventricular (AMI) were established by ligation of the left anterior descending coronary artery. Twenty-four hours after the operation, the rats were randomized into control and experimental groups for intragastric administration of normal saline (control), fosinopril and PNS at the low, medium and high doses for 4 consecutive weeks. The effects of PNS on the cardiac function index including the left ventricular end-diastolic dimension (LVIDd), left ventricular end-systolic diameter (LVIDs), ejection fraction (EF), percentage of left ventricular systole (FS), mitral early diastolic flow velocity mouth (MV), and heart rate (HR) were observed, and the changes in TNF-alpha and MMP-2 expression were detected after post-myocardial infarction ventricular remodeling.

RESULTSCompared with the control group, PNS at the medium and high doses produced significant improvements in the EF, FS and MV of the rats (P<0.01 or 0.05). TNF-alpha and MMP-2 expressions were significantly decreased by PNS treatment at low, medium and high doses (P<0.01).

CONCLUSIONPNS can inhibit or reduce the expression of TNF-alpha and MMP-2, thereby enhancing left ventricular systolic and diastolic functions, decreasing peripheral resistance, and improving the cardiac function of rats with post-myocardial infarction left ventricular remodeling.

Animals ; Female ; Male ; Matrix Metalloproteinase 2 ; metabolism ; Myocardial Infarction ; drug therapy ; physiopathology ; Panax notoginseng ; chemistry ; Rats ; Rats, Sprague-Dawley ; Saponins ; pharmacology ; therapeutic use ; Tumor Necrosis Factor-alpha ; metabolism ; Ventricular Remodeling ; drug effects

OBJECTIVETo reveal the relationship among congenital Toxoplasma gondii (T. gondii) infection, T lymphocyte cell subsets in umbilical cord blood and pregnancy outcome.

METHODS784 umbilical cord blood samples were collected and information of pregnancy outcomes was collected in a hospital of Hefei city, Anhui province during March 2009 to May 2010. T. gondii IgM antibodies in the sera were detected by ELISA. For all neonates infected with T. gondii and 10 healthy neonates, T lymphocyte cell subsets were detected by flow cytometry.

RESULTSAccording to the detection results of T. gondii IgM antibodies, 784 neonates were divided into infection group (21 neonates) and control group (763 neonates). The body weight and 1 min Apgar score of infection group were (3116.4 ± 352.6) g and (8.21 ± 1.26) points, respectively, which were statistically lower than control group ((3220.1 ± 242.3) g and (8.77 ± 1.61) points, respectively) (P < 0.01). The proportion of adverse pregnancy outcome of infection group was 19.0% (4/21), which was statistically greater than control group (4.8%, 37/763) (P < 0.01). The percentage of CD(3)(+) T lymphocyte cells in umbilical cord blood in infection group with and without adverse pregnancy outcomes were (64.51 ± 5.27)% and (64.32 ± 4.56)%, respectively, which were statistically lower than control group ((69.32 ± 4.32)%) (P < 0.01). The ratio value of CD(4)(+)/CD(8)(+) in infection group with, without adverse pregnancy outcomes and control group are 1.39 ± 0.24, 1.64 ± 0.28 and 2.34 ± 0.46, respectively, which showed statistical difference between any 2 groups (P < 0.01).

CONCLUSIONT. gondii infection leads to adverse pregnancy outcomes and disorder of cellular immunity while T lymphocyte cell subsets are closely associated with adverse pregnancy outcome.

Case-Control Studies ; Female ; Fetal Blood ; cytology ; immunology ; Humans ; Infant, Newborn ; Pregnancy ; Pregnancy Outcome ; T-Lymphocyte Subsets ; immunology ; Toxoplasmosis, Congenital ; immunology

OBJECTIVETo investigate the association between rs9722 polymorphisms in the S100B gene and hand, foot and mouth disease (HFMD) caused by enterovirus 71.

METHODSA total of 124 HFMD children with enterovirus 71 infection were enrolled as subjects, and 56 healthy children were enrolled as control group. The rs9722 polymorphisms in the S100B gene were detected for both groups, and the serum level of S100B protein was measured for 74 HFMD children.

RESULTSThe rs9722 locus of the S100B gene had three genotypes, CC, CT, and TT, and the genotype frequencies were in accordance with Hardy-Weinberg equilibrium. Compared with the control group, the HFMD group had significant increases in the frequencies of TT genotype and T allele (P<0.01). Children with severe HFMD caused by enterovirus 71 infection had significantly higher frequencies of TT genotype and T allele than those with moderate or mild HFMD (P<0.05). Compared with the cured patients, the patients with poor prognosis had significant increases in the frequencies of TT genotype and T allele in the rs9722 locus of the S100B gene (P<0.05). Among the 74 children with HFMD, the children with TT genotype had the highest serum level of S100B protein, and those with CC genotype had the lowest level (P<0.01).

CONCLUSIONST allele in the rs9722 locus of the S100B gene might be a risk factor for severe HFMD caused by enterovirus 71 infection.

Child, Preschool ; Enterovirus A, Human ; Enterovirus Infections ; complications ; Female ; Genotype ; Hand, Foot and Mouth Disease ; etiology ; genetics ; Humans ; Infant ; Male ; Polymorphism, Genetic ; S100 Calcium Binding Protein beta Subunit ; genetics

BACKGROUNDGlobally, the proportion of child deaths that occur in the neonatal period remains a high level of 37-41%. Differences of cause in neonate death exist in different regions as well as in different economic development countries. The specific aim of this study was to investigate the causes, characteristics, and differences of death in neonates during hospitalization in the tertiary Neonatal Intensive Care Unit (NICU) of China.

METHODSAll the dead neonates admitted to 26 NICUs were included between January l, 2011, and December 31, 2011. All the data were collected retrospectively from clinical records by a designed questionnaire. Data collected from each NICU were delivered to the leading institution where the results were analyzed.

RESULTSA total of 744 newborns died during the 1-year survey, accounting for 1.2% of all the neonates admitted to 26 NICUs and 37.6% of all the deaths in children under 5 years of age in these hospitals. Preterm neonate death accounted for 59.3% of all the death. The leading causes of death in preterm and term infants were pulmonary disease and infection, respectively. In early neonate period, pulmonary diseases (56.5%) occupied the largest proportion of preterm deaths while infection (27%) and neurologic diseases (22%) were the two main causes of term deaths. In late neonate period, infection was the leading cause of both preterm and term neonate deaths. About two-thirds of neonate death occurred after medical care withdrawal. Of the cases who might survive if receiving continuing treatment, parents' concern about the long-term outcomes was the main reason of medical care withdrawal.

CONCLUSIONSNeonate death still accounts for a high proportion of all the deaths in children under 5 years of age. Our study showed the majority of neonate death occurred in preterm infants. Cause of death varied with the age of death and gestational age. Accurate and prompt evaluation of the long-term outcomes should be carried out to guide the critical decision.

Cause of Death ; China ; Female ; Hospital Mortality ; Humans ; Infant ; Infant Mortality ; Infant, Newborn ; Infant, Newborn, Diseases ; mortality ; Intensive Care Units, Neonatal ; statistics & numerical data ; Male ; Perinatal Death ; Retrospective Studies