Research Progress on the Etiology,Diagnosis and Treatment of Neonatal Necrotizing Enterocolitis

Necrotizing enterocolitis(NEC)is a leading cause of death from gastrointestinal disease in premature and low-birth-weight infants.Early detection of severely ischemic or necrotic bowel before perforation is rather difficult.New techniques including multi-omics contribute to better understanding its underlying mechanisms and discovering differe categories of biomarkers.Combination of clinical metrics such as seven components of metabolic derangement(CMD)may provide accurate assessment of its severity.Implementation of quality improvement initiatives including breast milk feeding actually lowers its incidence.

Clinical association between coagulation indicators and bone metastasis in patients with gastric cancer

BACKGROUND Bones are one of the most common target organs for cancer metastasis.Early evaluation of bone metastasis(BM)status is clinically significant.Cancer patients often experience a hypercoagulable state.AIM To evaluate the correlation between coagulation indicators and the burden of BM in gastric cancer(GC).METHODS We conducted a single-center retrospective study and enrolled 454 patients.Clinical information including routine blood examination and coagulation markers were collected before any treatment.Patients were grouped according to the status of BM.Receiver operating characteristic curves were used to assess diagnostic performance and determine the optimal cutoff values of the above indicators.Cutoff values,sensitivity and specificity were based on the maximum Youden index.Univariate and multivariate logistic regression analyses were used to evaluate the relationships between biomarkers and BM.RESULTS Of the 454 enrolled patients,191 patients were diagnosed with BM.The receiver operating characteristic curve analysis suggested that prothrombin time(PT)Wang X et al.Coagulation indicators predict bone metastasis WJGO https://www.wjgnet.com 1254 July 15,2023 Volume 15 Issue 7[cutoff:13.25;sensitivity:0.651;specificity:0.709;area under receiver operating characteristic curve(AUC)=0.738],activated partial thromboplastin time(aPTT)(cutoff:35.15;sensitivity:0.640;specificity:0.640;AUC=0.678)and fibrin degradation products(FDP)(cutoff:2.75;sensitivity:0.668;specificity:0.801;AUC=0.768)act as novel predictors for BM.Based on multivariate logistic regression analysis,the results showed the independent correlation between PT[odds ratio(OR):3.16;95%confidence interval(CI):1.612-6.194;P=0.001],aPTT(OR:2.234;95%CI:1.157-4.313;P=0.017)and FDP(OR:3.17;95%CI:1.637-6.139;P=0.001)and BM in patients with GC.Moreover,age,carcinoembryonic antigen,erythrocyte and globulin were found to be significantly associated with BM.CONCLUSION Coagulation markers,namely PT,aPTT and FDP,might be potential predictors for screening BM in patients with GC.

Evaluation of immunoprotection against coronavirus disease 2019:Novel variants,vaccine inoculation,and complications

The strikingly rapidly mutating nature of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)genome has been a constant challenge during the coronavirus disease 2019(COVID-19)pandemic.In this study,various techniques,including reverse transcription-quantitative polymerase chain reaction,antigen-detection rapid diagnostic tests,and high-throughput sequencing were analyzed under different scenarios and spectra for the etiological diagnosis of COVID-19 at the population scale.This study aimed to summarize the latest research progress and provide up-to-date understanding of the methodology used for the evaluation of the immunoprotection conditions against future variants of SARS-CoV-2.Our novel work reviewed the current methods for the evaluation of the immunoprotection status of a specific population(endogenous antibodies)before and after vaccine inoculation(administered with biopharmaceutical antibody products).The present knowledge of the immunoprotection status regarding the COVID-19 complications was also discussed.Knowledge on the immunoprotection status of specific populations can help guide the design of pharmaceutical antibody products,inform practice guidelines,and develop national regulations with respect to the timing of and need for extra rounds of vaccine boosters.

Neuroprotective effects of autophagy inhibition on hippocampal glutamate receptor subunits after hypoxia-ischemia-induced brain damage in newborn rats

Autophagy has been suggested to participate in the pathology of hypoxic-ischemic brain damage（HIBD）.However,its regulatory role in HIBD remains unclear and was thus examined here using a rat model.To induce HIBD,the left common carotid artery was ligated in neonatal rats,and the rats were subjected to hypoxia for 2 hours.Some of these rats were intraperitoneally pretreated with the autophagy inhibitor 3-methyladenine（10 m M in 10 μL） or the autophagy stimulator rapamycin（1 g/kg） 1 hour before artery ligation.Our findings demonstrated that hypoxia-ischemia-induced hippocampal injury in neonatal rats was accompanied by increased expression levels of the autophagy-related proteins light chain 3 and Beclin-1 as well as of the AMPA receptor subunit GluR 1,but by reduced expression of GluR 2.Pretreatment with the autophagy inhibitor 3-methyladenine blocked hypoxia-ischemia-induced hippocampal injury,whereas pretreatment with the autophagy stimulator rapamycin significantly augmented hippocampal injury.Additionally,3-methyladenine pretreatment blocked the hypoxia-ischemia-induced upregulation of Glu R1 and downregulation of GluR2 in the hippocampus.By contrast,rapamycin further elevated hippocampal Glu R1 levels and exacerbated decreased GluR2 expression levels in neonates with HIBD.Our results indicate that autophagy inhibition favors the prevention of HIBD in neonatal rats,at least in part,through normalizing Glu R1 and GluR2 expression.

Study on the neurotoxic effects of low-level lead exposure in rats

Objective: To investigate effects of developmental lead exposure on nitric oxide synthase (NOS) activity in different brain regions and on N-methyl-D-aspartate (NMDA) receptor mRNA expression in the hippocampus of rats. On the basis of these observations, we explored possible mechanisms by which lead exposure leads to impaired learning and memorizing abilities in children. Methods: A series of rat animal models exposed to low levels of lead during the developing period was established (drinking water containing 0.025%, 0.05% and 0.075% lead acetate). NOS activities in the hippocampus, the cerebral cortex, the cerebellum and the brain stem were determined with fluorescence measurement and levels of mRNA expression of the NMDA receptor 2A (NR2A) subunit and NMDA receptor 2B (NR2B) subunit in the rat hippocampus were measured with Retro-translation (RT-PCR). Results: There were no differences in the body weight of rat pups between any of the groups at any given time (P>0.05). The blood lead level of Pb-exposed rat pups showed a systematic pattern of change: at 14 d of age, it was lower than that at 7 d of age, then rising to the peak level at 21 d and finally falling to lower levels at 28 d. The hippocampal NOS activities of lead-exposed groups were all lower than that of the control group on the 21 st and 28th day (P<0.01). NOS activities in the cerebellum of lead-exposed groups were all lower than that of the control group on the 21 st and 28th day (P<0.001) and the NOS activity of the 0.025% group was significantly lower than that of the 0.05% and 0.075% groups on the 28th day (P<0.05).NOS activity in the cerebral cortex of the 0.075% group was significantly lower than that of the control, 0.025% and 0.05% groups on the four day spans (P<0.001). There was no significant difference of NOS activity in the brain stem between any lead-exposed group and the control group on the four day spans. In the 0.05% and the 0.075% groups, the level of NR2A mRNA expression was higher than that in the control group at 7 d and 14 d of age (P<0.05). In the 0.025% group, the level of NR2A was found to be higher than that in the control group at 7 d of age only (P<0.05). No significant differences were found for the levels of NR2B mRNA expression between any of the groups at any given time. Conclusions: NOS activity in the hippocampus, the cerebral cortex and the cerebellum are inhibited by lead exposure. The degree of the inhibitory effect depends on the time span of exposure and the lead concentration. Developmental low-level lead exposure was found to raise the level of NR2A mRNA expression in the hippocampus of rats. Developmental low-level lead exposure does not affect the level of NR2B mRNA expression in the hippocampus.

Indoor Allergen Levels and Household Distributions in Nine Cities Across China

Objective Chinese allergic subjects have high levels of sensitization to house dust mite （HDM） and other indoor allergens. This study quantifies common indoor allergen levels in Chinese households. Methods Dust samples were collected from nine cities. Major allergens Der p 1 and Der f I from Dermatophagoides pteronyssinus and D. farinae, and specific antigens of Blomia tropicalis, Tyrophagus putrescentiae, Acarus siro, and cockroach species Blattella germanica and Periplaneta americana were measured by ELISA.Results HDM allergens were found in dust samples from bedding in 95% of the Chinese households. The median levels varied from 〈0.006 to 9.2 μg/g of dust, depending on the city. The percentages of households having HDM allergen levels associated with the risk of developing allergy sensitization and asthma were 65% and 25%, respectively. Specific antigens of the storage mite and cockroach were only found in samples from the southern and tropical regions of China. Levels of mite allergens were generally higher in samples from bedding compared to samples from the living room, even for storage mites, whereas levels of cockroach antigens were higher in the living room samples.Conclusion HDM allergens are present in bedding dust samples from most Chinese households. Cities in southern and central China have relatively high levels of HDM major allergens compared to cities in northern and western China. Antigens of storage mites and cockroaches are not as common as HDM allergens.

The treatment of relapsing primary nephrotic syndrome in children

Objective: To explore better therapy and reduce the rate of re-relapse of primary nephritic syndrome in children who had been treated with corticosteroids but relapsed. Methods: Eighty relapsers were enrolled from Jan. 1994 to Apr. 2000, who were randomly divided into two groups. The treatment group (n=39) had been treated with tripterysium glucosides for three months,with the control group (n=41) members were treated with cyclophosphmide (CTX) by intermission intravenous pulse, with total dose of CTX not being more than 150 mg/kg. Prednisone, meanwhile, was given to both groups. The total treatment period of prednisone was prolonged by 12-18 months. Results: After following up for 3-7 years, the re-relapse rates of both groups were observed. The re-relapse rate of the treatment group was 28.2% to 29.3% in the CTX-controlled group. The re-relapse rates between two groups were almost similar, and with no observed significant difference (P>0.05). The side effect of tripterysium glucosides was less than that of CTX. Conclusion: For the treatment of relapsing nephritic syndrome in children, the combination of tripterysium glucosides and prolonged corticosteroid therapy is as effective as the regimen of CTX plus prolonged use of prednisone.

Absorption Characteristics of Novel Compound Calcium Carbonate Granules:Effects of Gastric Acid Deficiency and Exogenous Weak Acids

Calcium carbonates are commonly administered as supplements for conditions of calcium deficiency.We report here pharmacokinetic characteristics of a novel formulation,calcium carbonate compound granules(CCCGs).forming complexes of calcium carbonate and calcium citrate in water.CCCGs were compared to a kind of commonly?used calcium carbonate preparation(CC)in the market in 5-week-old mice that had been treated with omeprazole,to suppress gastric acid secretion,and in untreated control mice.The results showed that:(1)CCCGs had better water solubility than CC in vitro;(2)In control mice,calcium absorption rates after CCCGs administration were comparable to those after CC administration;(3)Inhibition of gastric acid secretion did not affect calcium absorption after CCCGs,but moderately decreased it after CC;(4)The presence of phytic acid or tannin did not affect calcium absorption rates after CCCGs but did for CC;and(5)In nonnal mice,CCCGs did not inhibit gastric emptying and intestinal propulsion,and did not alter the gastrointestinal honnones.The results suggest that CCCGs may be therapeutically advantageous over more commonly used calcium supplement formulations,particularly for adolescents,because of their stable calcium absorption characteristics and their relatively favorable adverse effect profile.

Clinical significance of tumor-associated macrophage infiltration in supraglottic laryngeal carcinoma

Tumor-associated macrophages(TAMs) can elicit contrasting effects on tumor progression,depending on different tumor microenvironment.This study aimed to explore the correlation between TAM infiltration and clinicopathologic characteristics,metastasis,and prognosis of supraglottic laryngeal carcinoma.TAMs in intratumoral and peritumoral regions of 84 specimens of supraglottic laryngeal carcinoma tissues were detected by immunohistochemical staining with monoclonal CD68 antibody.The density of peritumoral CD68+ TAMs in recurrence cases(9/11) and in dead cases(17/23) were significantly higher than those in non-recurrence cases(33/73) and in survival cases(25/61),with significant differences(P = 0.024 and 0.007,respectively).The Kaplan-Meier survival analysis showed a significant relationship between the infiltration of both intratumoral and peritumoral CD68 + TAMs and the overall survival of patients.The 5year survival rate was significantly lower in the group with a high density of intratumoral CD68+ TAMs than in the group with a low density(39.6% vs.82.5%,P < 0.05).Similarly,the 5-year survival rate was significantly lower in the group with a high density of peritumoral CD68+ TAMs than in the group with a low density(50.6% vs.73.1%,P < 0.05).Cox regression analysis revealed that T classification,distant metastasis,and intratumoral or peritumoral CD68 + TAMs were independent factors for disease-free survival,whereas T classification and intratumoral CD68 + TAMs were independent factors for overall survival.The results indicate that TAM infiltration in supraglottic laryngeal carcinoma can be used to predict metastasis and prognosis and is an independent factor for prognosis.

Effects of IGF-Ⅱ on promoting proliferation and regulating nitric oxide synthase gene expression in mouse osteoblast-like cell

Objective: To investigate the effects of insulin-like growth factor Ⅱ (IGF-Ⅱ) on promoting cell proliferation, regulating levels of cellular nitric oxide (NO) and mRNA transcriptions of inducible nitric oxide synthase (iNOS) and endothelial NOS (eNOS) in mouse osteoblast-like cells. Methods: Mouse osteoblastic cell line MC3T3-E1 was selected as the effective cell of IGF-Ⅱ. After the cells were treated with IGF-Ⅱ at different concentrations for different time duration,3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) colorimetric assay was used to examine cell proliferation,and nitrate reductase method was applied to detect NO concentrations in cell culture supernatants and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was employed to determine transcription levels of cellular iNOS and eNOS mRNAs. Results: After the MC3T3-E 1 cells were treated with IGF-Ⅱ at concentration of 1 ng/ml for 72 h, 10 and 100 ng/ml for 24,48 and 72 h respectively, all the MTT values increased (P<0.05 or P<0.01) with obvious dosage-time dependent pattern. NO levels of the MC3T3-E1 cells treated with 100 ng/ml IGF-Ⅱ for 48 h, and with 1, 10 and 100 ng/ml IGF-Ⅱ for 72 h were remarkably lower than that of the normal control, respectively (P<0.05 or P<0.01). After the cells were treated with 100 ng/ml IGF-Ⅱ for 48 h cellular iNOS mRNA levels were significantly decreased (P<0.01). But the levels of eNOS mRNA in the cells treated with each of the used IGF-Ⅱ dosages for different time duration did not show any differences compared with the normal control (P>0.05).Conclusion: IGF-Ⅱ at different concentrations could promote proliferation of mouse MC3T3-E1 cell. This cell proliferation promotion was associated with the low NO levels maintained by IGF-Ⅱ. Higher concentration of IGF-Ⅱ could down-regulate iNOS gene expression at the level of transcription but not affect transcription of eNOS mRNA, which might be one of the mechanisms for IGF-Ⅱ maintenance of the low NO levels in MC3T3-E 1 cells.

The binding of MBL to common bacteria in infectious diseases of children

Objective:To purify Mannan-binding lectin(MBL)from human serum and detect its binding ability to several kindsof bacteria common in infections diseases of children.Methods:MBL was purifide from human serum by affinity chromatographyon mannan-Sepharose 4B column.Its binding ability to eight species,97 stratus of bacteria was detected by enzyme-linked lectinassay(ELLA).Results:MBL has different binding ability to bacteria and shows strong binding ability to Klebsiella ornithinolvticaand Escherichia coli,but shows relatively lower binding ability to Staphylococcus haemolyticus,Enterobacter cloacae andStaphylococcus epidermidis.To different isolates of Klebsiella pneumoniae,Haemophilus influenzae and Staphylococcus aureus,MBL shows quite different binding ability.Conclusions:MBL has different binding ability to different bacteria,and has relativelystronger binding ability to Gram-negative bacteria.Its binding ability to different isolates of certain kinds of bacteria is quitedifferent.

Expression of Clock genes in the pineal glands of newborn rats with hypoxic-ischemic encephalopathy

Clock genes are involved in circadian rhythm regulation, and surviving newborns with hypoxic-ischemic encephalopathy may present with sleep-wake cycle reversal. This study aimed to determine the expression of the clock genes Clock and Bmall, in the pineal gland of rats with hypoxic-ischemic brain damage. Results showed that levels of Clock mRNA v^re not significantly changed within 48 hours after cerebral hypoxia and ischemia. Expression levels of CLOCK and BMAL1 protein were significantly higher after 48 hours. The levels of Bmall mRNA reached a peak at 36 hours, but were significantly reduced at 48 hours. Experimental findings indicate that Clock and Bmall genes were indeed expressed in the pineal glands of neonatal rats. At the initial stage （within 36 hours） of hypoxic-ischemic brain damage, only slight changes in the expression levels of these two genes were detected, followed by significant changes at 36-48 hours. These changes may be associated with circadian rhythm disorder induced by hypoxic-ischemic brain damage.

Autophagy inhibitor 3-methyladenine regulatesthe expression of LC3, Beclin-1 and ZnTs in ratcerebral cortex following recurrent neonatal seizures

BACKGROUND： Autophagy is a homeostatic process for intracellular recycling of bulk proteins and aging organelles. Increased autophagy has now been reported in experimental models of traumatic brain injury, stroke and excitotoxicity, and in patients with Alzheimer＇s disease and critical illness. The role of autophagy in developmental epilepsy, however, is unknown. The present study was to investigate the effects of recurrent neonatal seizure, in the presence and absence of autophagy inhibitor 3-methyladenine （3-MA）, on the acute phase gene expression of ZnTs, LC3 and Beclin-1 in rat cerebral cortex and the interaction among them.METHODS： Thirty-six Sprague-Dawley neonatal rats at postnatal day 6（P6） were randomly divided into three groups： a recurrent-seizures group （RS, n=12）, a 3-MA treated-seizure group （3-MA group, each rat pretreated with 3-methyladenine before seizures, 100nmol/μl/day, i.p., n=12） and a control group （n=12）. At 1.5 and 6 hours after the last seizures, the mRNA levels of ZnT1-ZnT3, microtubule-associated protein 1A/1B light chain 3 （LC3） and beclin-1 were detected using the real-time RT-PCR method. The LC3 protein level was examined by Western blotting.RESULTS： The levels of LC3, beclin-1 and ZnT-2 transcripts in the RS group elevated signi？ cantly at 1.5 and 6 hours after the last seizures compared with those in the control and 3-MA groups. At the interval of 1.5 hours, the mRNA level of ZnT-1 increased signi？ cantly after the last seizure compared with that in the control group. There was no signi？ cant difference in the transcript levels of ZnT-3 among the three groups. Linear correlation analysis showed that the expression of the ？ ve genes in the control group exhibited a signi？ cant inter-relationship. In the 3-MA group, however, the inter-relationship was only found between beclin-1 and ZnT-1. In the RS group, the inter-relationship was not observed.CONCLUSIONS： The autophagy/lysosomal pathway is immediately activated along with the elevated expression of ZnT1 and ZnT2 in the cerebral cortex after recurrent seizures. 3-MA is involved in the regulation of the autophagy/lysosomal pathway and ZnTs by down-regulating the expression of LC3 and beclin-1.

Liver, biliary and pancreatic injuries in pancreaticobiliary maljunction model in cats

BACKGROUND： Pancreaticobiliary maljunction is a high risk factor of pancreatitis and biliary tract cancer. How this maljunction affects the liver remains obscure. This study aimed to examine the effects of pancreaticobiliary maljunction on the liver, pancreas and gallbladder in a cat model.METHODS： A model of choledocho-pancreatic side-to-side ductal anastomosis was created in ten cats. Before the procedure,a small piece of tissue from the liver, pancreas and gallbladder was collected as a control. The common channel formation was checked by cholecystography. The livers, pancreases and gallbladders of these cats were harvested for histological examination. The expression of proliferating cell nuclear antigen in the gallbladder was examined with immunohistochemistry. RESULTS： Seven of the 10 cats survived for 6 months after surgery. The color of the liver was darker in the PBM model than the control specimen, with nodules on the surface. Histological examination showed ballooning changes and inflammatory infiltrations and the histopathological score increased significantly（P〈0.05）. Also, mitochondria swelling and lipid droplet in cytoplasm were observed under an electron microscope. The pancreas also appeared darker in the PBM model than the control specimen and dilated pancreatic ducts were found in three cats. Histopathological examination revealed vascular proliferation and inflammatory infiltration with numerous neutrophils. Gallbladder epithelial cells were featured by expanded endoplasmic reticulum, increased intercellular space and cellular nucleus deformation. The positive cells ofproliferating cell nuclear antigen were increased significantly（P〈0.05）. CONCLUSION： The present study demonstrated that pancreaticobiliary maljunction can lead to the injuries of the liver, pancreas and gallbladder.

Impact of physical activity on health-related quality of life in osteoporotic and osteopenic postmenopausal women:A systematic review

Objective:This meta-analysis included papers which evaluated the effects of physical activity on the health-related quality of life(HRQoL)of osteoporotic and osteopenic postmenopausal women.Methods:Four English databases were searched for relevant randomized clinical trials(RTCs)published from 1970 to June,2014.Eligible RCTs which used the Quality of Life Questionnaire of the European Foundation for Osteoporosis(QUALEFFO)as their outcome measure were selected for inclusion.Results:Five RCTs were included in the final meta-analysis.The results showed that physical activity produced favorable effects in the HRQoL domains of physical function(p=0.001)and pain(p=0.01),but not in other domains.Compared with a single exercise,combined exercise produced more favorable effects on both physical function(p=0.0004)and pain(p=0.02).Short-term physical activity produced significant favorable results in all general health domains of HRQoL(p=0.01),whereas middle-term physical activity produced significant improvements only in the physical function(p<0.01)domains of HRQoL.Long-term physical activity produced significant improvement only in the pain domains of HRQoL(p<0.01),and only in the physical activity group when compared with a control group.Conclusion:Only weak evidence supports the notion that physical activity effectively improves the health-related quality of life of osteoporotic and osteopenic postmenopausal women.Compared with a single exercise,combined exercise produced favorable effects on both physical function and pain.However,different lengths of exercise produced improvements in different domains.

The inhibitory effect of SEMA3C/3D mutations on Neuro-2a cells migration and axonal growth in patients with Hirschsprung′s disease

Objective:To explore the effect and mechanism of SEMA3C/3D mutations on axonal growth of neurons and cell migration in Hirschsprung′s disease(HSCR)patients.Methods:HEK293 Tcells were transfected with wild-type and mutant SEMA3C/3D plasmids.The supernatants that contained SEMA3C/3D-AP fusion proteins were collected and added into the Neuro-2acells.The changes in the cell morphology were observed by immunofluorescence staining.The expression and phosphorylation levels of cofilin,ERM and CRMP2 were determined by western blotting.The cell migration rate was measured by transwell assay.Results:Compared with wild-type SEMA3D,SEMA3D-P615T mutant suppressed cofilin phosphorylation in Neuro-2a cells(P <0.05).The neural cells treated by five mutant SEMA3C/3D-AP fusion proteins presented different levels of axon atrophy,growth cone collapse,and sometimes,loss of normal structure.SEMA3C-S329 G,SEMA3C-V337M and SEMA3D-P615T mutants cells exhibited a significantly reduced migration rate as compared with wild-type SEMA3C/3D treated cells(P <0.01).Conclusion:SEMA3C and SEMA3 D mutations in HSCR patients could lead to the inhibition of Neuro-2a cells′migration and axonal growth.The mechanism of SEMA3 DP615T mutant might be related to down-regulation of the expression of p-cofilin,which consequently lead to cytoskeleton structure collapse and migrating ability decrease.Our study might provide important clues for the pathogenesis of HSCR.

Posttraumatic stress symptom trajectories of Chinese university students during the first eight months of the COVID-19 pandemic and their association with cognitive reappraisal,expressive suppression,and posttraumatic growth

Objective: To identify the moderating effects of cognitive reappraisal(CR) and expressive suppression(ES) on the relationship between posttraumatic stress(PTS) symptoms and posttraumatic growth(PTG) in university students. Methods: The survey included 1 987 Chinese university students who completed questionnaires on PTS symptoms in February 2020, with three follow-up surveys at two-month intervals until August 2020. We assessed CR and ES at February 2020 and PTG at August 2020. Growth mixture modeling was used to classify the PTS symptom trajectories. Multinomial logistic regression was used to recognize the predictors of class membership. The relationships among PTS symptoms, CR, ES, and PTG were examined using multi-group path analysis.Results: Sex, SARS-Co V-2 infection of a family member or friend, number of siblings, CR, and ES were significantly associated with PTS symptoms. Three latent classes were identified: ‘Increasing PTS’(n=205, 10.0%) who had rapid deterioration of PTS symptoms, ‘Moderate PTS’(n=149, 8.0%) who had a high level of PTS symptoms at the beginning and slightly increasing, and ‘Persistent Minimal PTS’(n=1 633, 82.0%), who had slow resolution of PTS symptoms over time. Male, SARS-Co V-2 infection of a family member or friend, and having a lower CR and a higher ES, were more likely to have ‘Increasing PTS’. PTS at February 2020 predicted PTG only in ‘Increasing PTS’ class, and both CR and ES had moderating effects on the conversion between them.Conclusions: Most students recovered from posttraumatic stress of COVID-19 pandemic, but a small proportion expeienced increasing PTS symptoms, and those with this condition may benefit from emotional regulation intervention.

More common RNAemia in the early stage of severe SARS-CoV-2 BF.7.14 infections in pediatric patients

The risk factors of severe infections in children during the severe acute respiratory syndrome coronavirus 2(SARS‐CoV‐2)outbreak in Beijing remain elusive.SARS‐CoV‐2‐positive children admitted to the intensive care unit(ICU)with collected plasma specimens were enrolled and screened for common pathogens using capillary electrophoresis‐based multiplex PCR from December 12,2022,to January 24,2023.The SARS‐CoV‐2 subvariants were identified using next‐generation sequencing.Plasma was positive for two(positive;P),one(suspicious;S),or no(negative;N)SARS‐CoV‐2 genes were classified as plasmatic RNA‐positive(RNAemia;P+S)or without RNAemia(N).Clinical and laboratory data of the enrolled cases were then collected and analyzed.The 34 enrolled children included 26 males and 24 younger than three years.All were negative for other respiratory pathogens.BF.7.14(18/29)was the predominant subvariant.Viral loads in respiratory specimens,hours from symptom onset to the first respiratory specimen collection(time‐variable),with comorbidities and BF.7.14 and BA.5.2 distributions were significantly different in P vs.N and RNAemia vs.without RNAemia group.Among most cases,the T lymphocyte ratios decreased,while the cytokine level and the B lymphocyte ratio increased.The time variables were 2.22±2.05 and 4.00±2.49 days in BF.7.14 and BA.5.2 infections,respectively.In conclusion,SARS‐CoV‐2 was more likely to cause severe infections among males aged≤3 years old with comorbidities during the SARS‐CoV‐2 outbreak in Beijing,while RNAemia is more common in children at the early stage of severe BF.7.14 infections,and most had high cytokine levels and B‐cell activation.

BMP9 induces osteogenic differentiation through up-regulating LGR4 via the mTORC1/ Stat3 pathway in mesenchymal stem cells

Bone defects and non-union are prevalent in clinical orthopedy,and the outcomes of current treatments are often suboptimal.Bone tissue engineering offers a promising approach to treating these conditions effectively.Bone morphogenetic protein 9(BMP9)can commit mesenchymal stem cells to osteogenic lineage,and a knowledge of the underlying mechanisms may help advance the field of bone tissue engineering.Leucine-rich repeats con-taining G protein-coupled receptor 4(LGR4),a member of G protein-coupled receptors,is essential for modulating bone development.This study is aimed at investigating the impact of LGR4 on BMP9-induced osteogenesis in mesenchymal stem cells as well as the underlying mechanisms.Bone marrow stromal cells from BMp9-knockout mice exhibited diminished LGR4 expression,and exogenous LGR4 clearly restored the impaired osteogenic potency of the bone marrow stromal cells.Furthermore,LGR4 expression was increased by BMP9 in C3H10T1/2 cells.LGR4 augmented the benefits of BMP9-induced osteogenic markers and bone formation,whereas LGR4 inhibition restricted these effects.Meanwhile,the BMP9-induced li-pogenic markers were increased by LGR4 inhibition.The protein levels of Raptor and p-Stat3 were elevated by BMP9.Raptor knockdown or p-Stat3 suppression attenuated the osteoblastic markers and LGR4 expression brought on by BMP9.LGR4 significantly reversed the blocking ef-fect of Raptor knockdown or p-Stat3 suppression on the BMP9-induced osteoblastic markers.Raptor interacts with p-Stat3,and p-Stat3 activates the LGR4 promoter activity.In conclusion,LGR4 boosts BMP9 osteoblastic potency in mesenchymal stem cells,and BMP9 may up-regulate LGR4 via the mTORC1/Stat3 signal activation.

Expert consensus on the diagnosis, treatment, and prevention of respiratory syncytial virus infections in children

Background Respiratory syncytial virus(RSV)is the leading global cause of respiratory infections and is responsible for about 3 million hospitalizations and more than 100,000 deaths annually in children younger than 5 years,representing a major global healthcare burden.There is a great unmet need for new agents and universal strategies to prevent RSV infections in early life.A multidisciplinary consensus development group comprising experts in epidemiology,infectious diseases,respiratory medicine,and methodology aims to develop the current consensus to address clinical issues of RSV infections in children.Data sources The evidence searches and reviews were conducted using electronic databases,including PubMed,Embase,Web of Science,and the Cochrane Library,using variations in terms for"respiratory syncytial virus","RSV","lower respiratory tract infection","bronchiolitis","acute","viral pneumonia","neonatal","infant""children",and"pediatric".Results Evidence-based recommendations regarding diagnosis,treatment,and prevention were proposed with a high degree of consensus.Although supportive care remains the cornerstone for the management of RSV infections,new monoclonal antibodies,vaccines,drug therapies,and viral surveillance techniques are being rolled out.Conclusions This consensus,based on international and national scientific evidence,reinforces the current recommendations and integrates the recent advances for optimal care and prevention of RSV infections.Further improvements in the management of RSV infections will require generating the highest quality of evidence through rigorously designed studies that possess little bias and sufficient capacity to identify clinically meaningful end points.