OBJECTIVES: To analyze the clinical characteristics of diffuse panbronchiolitis (DPB) in children and to enhance the clinical diagnosis and treatment of this disease. METHODS: A retrospective analysis was conducted on the clinical data of 6 children diagnosed with DPB who were hospitalized at The First Affiliated Hospital of Guangzhou Medical University from January 2011 to December 2019. RESULTS: Among the 6 patients, there were 2 males and 4 females; the age at diagnosis ranged from 7 to 12 years. All patients presented with cough, sputum production, and exertional dyspnea, and all had a history of sinusitis. Two cases showed positive serum cold agglutinin tests, and 5 cases exhibited pathological changes consistent with chronic bronchiolitis. High-resolution chest CT in all patients revealed centrilobular nodules diffusely distributed throughout both lungs with a tree-in-bud appearance. Five patients received low-dose azithromycin maintenance therapy, but 3 showed inadequate treatment response. After empirical anti-tuberculosis treatment, non-tuberculous Mycobacteria were found in the bronchoalveolar lavage fluid. Follow-up over 2 years showed 1 case cured, 3 cases significantly improved, and 2 cases partially improved. CONCLUSIONS The clinical presentation of DPB is non-specific and can easily lead to misdiagnosis. In cases where DPB is clinically diagnosed but does not show improvement with low-dose azithromycin treatment, special infections should be considered.
Humans ; Male ; Female ; Bronchiolitis/drug therapy* ; Retrospective Studies ; Child ; Haemophilus Infections/diagnosis*

Objective:To explore the changes in plasma lipoprotein associated phospholipase A2(Lp-PLA2)and silencing information regulatory protein 1(SIRT1)in patients with sepsis complicated with acute kidney injury(AKI)and their relationship with short-term prognosis.Methods:243 sepsis patients who received treatment in our hospital from May 2022 to May 2024 were prospective selected,including 80 sepsis patients with AKI(AKI group)and 163 sepsis patients without AKI(non AKI group),the plasma Lp-PLA2 and SIRT1 levels between the two groups were compared.They were divided into good prognosis group and poor prognosis group according to 28 d prognosis after admission in AKI group.The influencing factors of short-term prognosis in sepsis patients complicated with AKI were analyzed by multiple logistic regression model.The short-term prognostic value of plasma Lp-PLA2 and SIRT1 alone and in combination for sepsis complicated with AKI patients was analyzed using receiver operating characteristic(ROC)curve.Results:Compared with non AKI group,AKI group had higher Lp-PLA2 and lower SIRT1(P＜0.05).39 deaths within 28 d after admission in AKI group(poor prognosis group),41 cases survived(good prognosis group),with poor prognosis rate of 48.75％(39/80).Sequential organ failure assessment(SOFA)score,acutephysiology and chronic health evaluationⅡ(APACHEⅡ)score,creatinine(Scr),lactate dehydrogenase albumin ratio(LAR)in poor prognosis group were higher than those in good prognosis group,while procalcitonin(PCT)was lower than that in good prognosis group(P＜0.05).Compared with the good prognosis group,poor prognosis group had higher Lp-PLA2 and lower SIRT1 at admission(P＜0.05).Elevated SOFA score,elevated Scr,elevated APACHEⅡ score,and elevated plasma Lp-PLA2 were risk factors for poor prognosis in sepsis patients complicated with AKI(P＜0.05),while elevated plasma SIRT1 was a protective factor(P＜0.05).ROC curve analysis results showed that,the combined detection of plasma Lp-PLA2 and SIRT1 predicted a poor prognosis for sepsis patients with AKI with an area under the curve(AUC)of 0.935,which was better than the prediction of 0.813 and 0.858 for plasma Lp-PLA2 and SIRT1 alone.Conclusion:Sepsis complicated with AKI patients have elevated plasma Lp-PLA2 and decreased SIRT1,combined detection of the two can assist in predicting the risk of poor prognosis.

Objective To use direct dilution method to pretreat human urine, and to determine 19 elements in human urine using inductively coupled plasma mass spectrometry, and to evaluate the uncertainty of the entire experimental process. Methods The relevant mathematical models were established according to JJF 10591-2012 ^“Evaluation and Expression of Measurement Uncertainty^” and CNAS-GL006 ^“Guidance for Evaluation of Uncertainty in Chemical Analysis^”. Taking molybdenum as an example, the uncertainty sources in the determination of 19 elements in human urine by inductively coupled plasma method were analyzed and evaluated, including sample pretreatment, sample repeated measurement, standard solution preparation and standard curve fitting. Results The extended uncertainty of molybdenum in human urine is 2.12μg/L, and the measurement result of molybdenum is (44.8±2.12)μg/L. The measurement result of 19 elements in human urine ranges from less than the detection limit to 601μg/L, and the extended uncertainty range is 0.38~33.6μg/L.Conclusion It was found from the calculation that the uncertainty of the determination result was mainly affected by the uncertainty of the sample repeated measurement and the standard curve fitting. By adjusting the range of standard curve and increasing the number of parallel sample measurement, the uncertainty was reduced and the quality of detection was improved.

Aim To explore the influence of demethy-lase fat mass and obesity-related genes(FTO)on the abnormal contractile function of diabetic coronary smooth muscle.Methods Smooth muscle specific FTO knockout mice(FTOSMKO)were prepared by Cre-loxP recombinant technology.They were divided into four groups:control(WT)group,diabetes model group(DM),FTO knockout group(FTOSMKO),and FTOSMKO diabetic group(FTOSMKO-DM),with 15 mice in each group.Diabetic mice were prepared by intraperitoneal injection of streptozotocin(STZ);the remaining mice were injected with an equal amount of citric acid-sodi-um citrate buffer.The effects of 5-HTon the contractile response of coronary artery smooth muscle in the four groups of mice were observed by the technique of small-vessel ring tensiometry.Western blot and Dot blot were used to detect the changes of FTO protein and N6-methyladenine(m6A)methylation modification levels in mouse vascular tissues.Results Compared with the WT group,the DM group had significantly higher blood glucose(P＜0.01)and lower body weight(P＜0.05);the level of FTO protein in aorta of DM group increased(P＜0.01),and the level of m6A methylation modification decreased(P＜0.01).The 5-HT-induced contractile response significantly de-creased in the DM group compared with the WT group(P＜0.01),whereas the contractile response signifi-cantly increased in the FTOSMKO-DM group compared with the DM group(P＜0.01);the non-L-type calci-um channel-mediated vascular smooth muscle contrac-tile response was enhanced in the FTOSMKO-DM group,among which,the contractions induced by 1,4,5-triphosphate inositol receptor(IP3R)and caffeine-ac-tivated ranine receptor(RyR)mediated by sarcoplas-mic reticulum calcium release both significantly in-creased(P＜0.05).Conclusions Specific knock-down of smooth muscle FTO improves coronary artery responsiveness to the vasoconstrictor 5-HT in diabetic mice,which may be related to abnormalities in the FTO-mediated 5-HT receptor signaling pathway.

BACKGROUND: P16 inactivation is frequently accompanied by telomerase reverse transcriptase ( TERT ) amplification in human cancer genomes. P16 inactivation by DNA methylation often occurs automatically during immortalization of normal cells by TERT . However, direct evidence remains to be obtained to support the causal effect of epigenetic changes, such as P16 methylation, on cancer development. This study aimed to provide experimental evidence that P16 methylation directly drives cancer development. METHODS: A zinc finger protein-based P16 -specific DNA methyltransferase (P16-Dnmt) vector containing a "Tet-On" switch was used to induce extensive methylation of P16 CpG islands in normal human fibroblast CCD-18Co cells. Battery assays were used to evaluate cell immortalization and transformation throughout their lifespan. Cell subcloning and DNA barcoding were used to track the diversity of cell evolution. RESULTS: Leaking P16-Dnmt expression (without doxycycline-induction) could specifically inactivate P16 expression by DNA methylation. P16 methylation only promoted proliferation and prolonged lifespan but did not induce immortalization of CCD-18Co cells. Notably, cell immortalization, loss of contact inhibition, and anchorage-independent growth were always prevalent in P16-Dnmt&TERT cells, indicating cell transformation. In contrast, almost all TERT cells died in the replicative crisis. Only a few TERT cells recovered from the crisis, in which spontaneous P16 inactivation by DNA methylation occurred. Furthermore, the subclone formation capacity of P16-Dnmt&TERT cells was two-fold that of TERT cells. DNA barcoding analysis showed that the diversity of the P16-Dnmt&TERT cell population was much greater than that of the TERT cell population. CONCLUSION P16 methylation drives TERT -mediated immortalization and transformation of normal human cells that may contribute to cancer development.
Humans ; Telomerase/genetics* ; DNA Methylation/physiology* ; Fibroblasts/cytology* ; Cyclin-Dependent Kinase Inhibitor p16/metabolism* ; Cell Line ; Cell Transformation, Neoplastic/genetics*

Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

Objective:To explore the changes in plasma lipoprotein associated phospholipase A2(Lp-PLA2)and silencing information regulatory protein 1(SIRT1)in patients with sepsis complicated with acute kidney injury(AKI)and their relationship with short-term prognosis.Methods:243 sepsis patients who received treatment in our hospital from May 2022 to May 2024 were prospective selected,including 80 sepsis patients with AKI(AKI group)and 163 sepsis patients without AKI(non AKI group),the plasma Lp-PLA2 and SIRT1 levels between the two groups were compared.They were divided into good prognosis group and poor prognosis group according to 28 d prognosis after admission in AKI group.The influencing factors of short-term prognosis in sepsis patients complicated with AKI were analyzed by multiple logistic regression model.The short-term prognostic value of plasma Lp-PLA2 and SIRT1 alone and in combination for sepsis complicated with AKI patients was analyzed using receiver operating characteristic(ROC)curve.Results:Compared with non AKI group,AKI group had higher Lp-PLA2 and lower SIRT1(P＜0.05).39 deaths within 28 d after admission in AKI group(poor prognosis group),41 cases survived(good prognosis group),with poor prognosis rate of 48.75％(39/80).Sequential organ failure assessment(SOFA)score,acutephysiology and chronic health evaluationⅡ(APACHEⅡ)score,creatinine(Scr),lactate dehydrogenase albumin ratio(LAR)in poor prognosis group were higher than those in good prognosis group,while procalcitonin(PCT)was lower than that in good prognosis group(P＜0.05).Compared with the good prognosis group,poor prognosis group had higher Lp-PLA2 and lower SIRT1 at admission(P＜0.05).Elevated SOFA score,elevated Scr,elevated APACHEⅡ score,and elevated plasma Lp-PLA2 were risk factors for poor prognosis in sepsis patients complicated with AKI(P＜0.05),while elevated plasma SIRT1 was a protective factor(P＜0.05).ROC curve analysis results showed that,the combined detection of plasma Lp-PLA2 and SIRT1 predicted a poor prognosis for sepsis patients with AKI with an area under the curve(AUC)of 0.935,which was better than the prediction of 0.813 and 0.858 for plasma Lp-PLA2 and SIRT1 alone.Conclusion:Sepsis complicated with AKI patients have elevated plasma Lp-PLA2 and decreased SIRT1,combined detection of the two can assist in predicting the risk of poor prognosis.

Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

Aim To explore the influence of demethy-lase fat mass and obesity-related genes(FTO)on the abnormal contractile function of diabetic coronary smooth muscle.Methods Smooth muscle specific FTO knockout mice(FTOSMKO)were prepared by Cre-loxP recombinant technology.They were divided into four groups:control(WT)group,diabetes model group(DM),FTO knockout group(FTOSMKO),and FTOSMKO diabetic group(FTOSMKO-DM),with 15 mice in each group.Diabetic mice were prepared by intraperitoneal injection of streptozotocin(STZ);the remaining mice were injected with an equal amount of citric acid-sodi-um citrate buffer.The effects of 5-HTon the contractile response of coronary artery smooth muscle in the four groups of mice were observed by the technique of small-vessel ring tensiometry.Western blot and Dot blot were used to detect the changes of FTO protein and N6-methyladenine(m6A)methylation modification levels in mouse vascular tissues.Results Compared with the WT group,the DM group had significantly higher blood glucose(P＜0.01)and lower body weight(P＜0.05);the level of FTO protein in aorta of DM group increased(P＜0.01),and the level of m6A methylation modification decreased(P＜0.01).The 5-HT-induced contractile response significantly de-creased in the DM group compared with the WT group(P＜0.01),whereas the contractile response signifi-cantly increased in the FTOSMKO-DM group compared with the DM group(P＜0.01);the non-L-type calci-um channel-mediated vascular smooth muscle contrac-tile response was enhanced in the FTOSMKO-DM group,among which,the contractions induced by 1,4,5-triphosphate inositol receptor(IP3R)and caffeine-ac-tivated ranine receptor(RyR)mediated by sarcoplas-mic reticulum calcium release both significantly in-creased(P＜0.05).Conclusions Specific knock-down of smooth muscle FTO improves coronary artery responsiveness to the vasoconstrictor 5-HT in diabetic mice,which may be related to abnormalities in the FTO-mediated 5-HT receptor signaling pathway.

Objective To investigate the environmental contamination related to first patient with carbapenem-re-sistant Acinetobacter baumannii(CRAB)infection and the infection status of relevant patients in a newly established intensive care unit(ICU)of a hospital in Tibetan area,and analyze the transmission risk.Methods From the ad-mission in ICU of a patients who was first detected CRAB on November 15,2021 to the 60th day of hospitalization,all patients who stayed in ICU for＞48 hours were performed active screening on CRAB.On the 30th day and 60th day of the admission to the ICU of the first CRAB-infected patient,environment specimens were taken respectively 2 hours after high-frequency diagnostic and therapeutic activities but before disinfection,and after disinfection but before medical activities.CRAB was cultured with chromogenic culture medium.Results Among the 13 patients who were actively screened,1 case was CRAB positive,he was transferred from the ICU of a tertiary hospital to the ICU of this hospital on November 19th.On the 40th day of admission to the ICU,he had fever,increased frequency for sputum suction,and CRAB was detected.The drug sensitivity spectrum was similar to that of the first case,and he also stayed in the adjacent bed of the first case.64 environmental specimens were taken,and 9 were positive for CRAB,with a positive rate of 14.06％,8 sampling points such as the washbasin,door handle and bed rail were positive for CRAB after high-frequency diagnostic and therapeutic activities.After routine disinfection,CRAB was detected from the sink of the washbasin.Conclusion For the prevention and control of CRAB in the basic-level ICU in ethnic areas,it is feasible to conduct risk assessment on admitted patients and adopt bundled prevention and con-trol measures for high-risk patients upon admission.Attention should be paid to the contaminated areas(such as washbasin,door handle,and bed rail)as well as the effectiveness of disinfection of sink of washbasin.