The value of bronchoalveolar lavage fluid genechip analysis for the identification of pathogens in children with refractory pneumonia / 中华实用儿科临床杂志

Objective:To investigate the value of bronchoalveolar lavage fluid (BALF) genechip analysis for the identification of pathogens in children with refractory pneumonia.Methods:A retrospective study of 500 children clinically diagnosed with refractory pneumonia in the Department of Respiratory and Critical Care Medicine, Kunming Children′s Hospital, Kunming Medical University between January 2020 to January 2022 was made.During hospitalization, bronchoscopic examination and bronchoalveolar lavage were performed.BALF was collected and analyzed using genechip technology to detect potential pathogens.At the same time, bacterial culture tests of sputum and BALF samples from the patients were performed. χ2 test was used to compare the positive rates of pathogens detected by different detection methods. Results:Of the 500 children patients, 482 cases (96.4%) were positive of BALF genechip analysis for pathogen identification.There were 71 cases (14.7%) infected with a single pathogen, and 411 cases (85.3%) with 2 or more pathogens.The top 3 bacteria were Streptococcus pneumoniae [117 cases (8.3%)], Haemophilus influenzae [63 cases (4.5%)], and Bordetella pertussis [32 cases (2.3%)]. The patients were mostly infected with respiratory syncytial virus [269 cases (19.1%)], followed by parainfluenza virus [217 cases (15.4%)], and adenovirus [132 cases (9.3%)]. Among the 500 patients, 116 cases (23.2%) were positive of BALF genechip analysis for bacteria identification, 47 cases (9.4%) had a positive BALF culture, 43 cases (8.6%) had a positive sputum culture.The bacterial detection rate of BALF genechip analysis was statistically significantly higher than that of BALF culture and sputum culture tests ( χ2=34.90, 39.85; all P<0.001). Conclusions:Most patients with refractory pneumonia have mixed infections.The genechip technology can rapidly and efficiently identify the pathogens, thus providing clinical guidance for anti-infection treatment.

Progress of unfolded protein response in acute respiratory distress syndrome / 国际儿科学杂志

Acute respiratory distress syndrome(ARDS)is a severe respiratory disease in children and the pathogenesis is not fully defined.It is mainly related to various mechanisms of lung injury such as inflammation and autophagy.In recent years, studies have found that, endoplasmic reticulum stress(ERS)can aggravate lung injury in ARDS, in which protein homeostasis imbalance can induce activation of the unfolded protein response(UPR).The UPR reconstructs homeostasis by mediating transmembrane protein-related signaling pathways, while continuous excessive ERS will promote apoptosis and autophagy.This review summarizes the progress of the signaling pathway of UPR related to lung injury and its inflammatory effect in ARDS.

Mechanism, prevention and treatment of acute lung injury caused by 2019-nCoV infection / 国际儿科学杂志

The main target organ of 2019 novel coronavirus(2019-nCoV)was the lung and acute respiratory distress syndrome, a life-threatening condition, could happen in severe cases.The main receptor of 2019-nCoV is angiotensin-converting enzyme 2(ACE2). Other receptors reported included CD147, tyrosine protein kinase receptor UFO, Neuropilin-1, Kidney injury molecule-1, et al.When 2019-nCoV is bound with ACE2, the expression of ACE2 would be down-regulated, which causes an increased angiotensin level and consequent lung injury through downstream signals.In addition, 2019-nCoV infection can induce inflammatory cytokine storm, cause coagulation dysfunction, trigger lung epithelial cell apoptosis, et al, which collaboratively contribute to lung injury.The clinical symptoms of 2019-nCoV infection in children are mild, which is thought due to the advantages of children in innate immune response and the low level of adaptive immune response.The fundamental means to prevent and treat lung injury was inhibiting the proliferation and replication of the 2019-nCoV virus, but so far, there are no specific antiviral drugs found yet.Approaches like recombinant human soluble ACE2 protein, neutralizing antibody against protein S, inhibiting angiotensinⅡ, contradicting inflammation factors, or stem cell infusion may be helpful to prevent and alleviate lung injury.

Clinical application of dexmedetomidine in pediatrics / 中国小儿急救医学

Dexmedetomidine(DEX) is a new type of highly selective α 2 adrenergic receptor agonist with multiple effects, such as sedation, analgesic, anti-anxiety and inhibition of sympathetic nervous system activity.DEX is usually used as an anesthetic adjuvant and as an sedative and analgesic in PICU, also possessing effects of preventing and treating emergence agitation, counteracting postoperative shivering and organ protection.This paper summarized the clinical application of DEX in pediatric field.

Clinical application of dexmedetomidine in pediatrics / 中国小儿急救医学

Dexmedetomidine(DEX) is a new type of highly selective α2 adrenergic receptor agonist with multiple effects, such as sedation, analgesic, anti-anxiety and inhibition of sympathetic nervous system activity.DEX is usually used as an anesthetic adjuvant and as an sedative and analgesic in PICU, also possessing effects of preventing and treating emergence agitation, counteracting postoperative shivering and organ protection.This paper summarized the clinical application of DEX in pediatric field.

High altitude pulmonary edema in children / 中国小儿急救医学

High altitude pulmonary edema(HAPE) occurs usually in plateau of low oxygen environ-ment,which is a non-cardiogenic pulmonary edema characterized by hypoxic pulmonary hypertension. Children HAPE has an acute onset and rapid progression.It always happens during the first 1 to 3 days ente-ring the plateau and has clear trigger factors such as upper respiratory tract infection,many physical labour and coldness. The pathogenesis is related with hypoxic pulmonary artery contraction,pulmonary epithelial dysfunction,inflammatory response,water transport imbalance in pulmonary epithelium,and genetic polymor-phism.The early symptoms include crying,breath holding,and dry cough. With the disease progressing, patients will present shortness of breath and expectoration of pink foam sputum,and even be unconscious, which results from cerebral edema and is mortal.The treatments of HAPE include bed rest,oxygen therapy, reduction of pulmonary arterial hypertension,hormone,diuresis,prevention of infection and so on.

The problems concerned on diagnosis and treatment of refractory Mycoplasma pneumoniae pneumonia / 中华实用儿科临床杂志

Refractory mycoplasma pneumoniae pneumonia is clinically increasing and has become a common disease that threatens children's lives. This article will introduce the concepts,mechanism,Mycoplasma pneumoniae re-sistance,systemic manifestation,early diagnosis and treatment of refractory mycoplasma pneumoniae pneumonia. Addi-tionally,the reports of pleural effusion and embolism caused by Mycoplasma pneumoniae are increased recently;the achievements on the topic are also reviewed.

Effects of calcitonin gene-related peptide on aquaporin 1 and aquaporin 5 expressions in young rats with acute lung injury / 中华实用儿科临床杂志

Objective To explore the effect of calcitonin gene-related peptide (CGRP) on expressions of aquaporin (AQP)1 and AQP 5 in young rats with acute lung injury (ALI) caused by lipopolysaccharide (LPS).Methods Eighty-four young rats were randomly divided into control group,ALI model group and CGRP group.The rats in ALI model group were given intraperitoneal injection of LPS (5 mg/kg)for 2,6,12,24 hours;while the rats in CGRP group were given intraperitoneal CGRP (1 mg/kg) after 1 h injection of LPS.At 2 h,6 h,12 h and 24 h,all rats were sacrificed and lung tissues were obtained.The histopathological changes in lung tissues were evaluated by adopting hematoxylin-eosin staining,and wet/dry(W/D) was measured.The mRNA and protein levels of AQP1 and AQP5 in lung tissues were detected by adopting fluorogenic quantitative PCR (qPCR) and Western blot.Results Pathological stain showed that rats in control group had a normal lung tissue structure,and LPS made lung tissue edema,narrowing the alveolar cavity and inflammatory cell infiltration.CGRP attenuated the effect of LPS on rat's lung.The W/D ratio of lung tissue was significantly higher than that in the control group,and CGRP reduced the W/D ratio of lung tissue.qPCR showed that the mRNA levels of AQP1 and AQP5 from rats in ALI group (0.009 ±0.001 and 0.055 ±0.006)decreased compared with those in the control group (0.035±0.002 and 0.167 ±0.006) and CGRP group (0.024 ± 0.002 and 0.134 ± 0.012) (all P ＜ 0.001).Western blot results showed after 24 h injection of LPS,both AQP1 and AQP5 levels from ALI group (0.397 ± 0.041 and 0.215 ± 0.029) were significantly lower than those in the control group (0.850 ± 0.020 and 0.741 ± 0.032) (all P ＜ 0.001),and their levels in CGRP group (0.593-± 0.065 and 0.461 ± 0.039) were also lower than those in the control group,but higher than those in ALI group (all P ＜ 0.001).Conclusion CGRP can enhance AQP1 and AQP5 levels and reduce pulmonary edema,and it has a protective effect on rats with acute lung injury.

Calcitonin gene-related peptide and lung diseases / 国际儿科学杂志

Pulmonary diseases include infection,injury,asthma,interstitial disease,tumor,hypertension and so on.The mechanisms are not fully understood.Calcitonin gene-related peptide(CGRP),a 37-amino acid neuropeptide,identified in multiple species,has widespread distribution and expression.Although there are no cases that CGRP works in pulmonary disease,many studies have showed that CGRP play an important role on cell line in vitro or on animal models.This brief review provides a preliminary understanding of the diverse biological effects of CGRP and its antagonist in respiratory system.

Effects of calcitonin gene-related peptide on aquaporin 1 and aquaporin 5 expressions in young rats with acute lung injury / 中华实用儿科临床杂志

Objective To explore the effect of calcitonin gene-related peptide (CGRP) on expressions of aquaporin (AQP)1 and AQP 5 in young rats with acute lung injury (ALI) caused by lipopolysaccharide (LPS).Methods Eighty-four young rats were randomly divided into control group,ALI model group and CGRP group.The rats in ALI model group were given intraperitoneal injection of LPS (5 mg/kg)for 2,6,12,24 hours;while the rats in CGRP group were given intraperitoneal CGRP (1 mg/kg) after 1 h injection of LPS.At 2 h,6 h,12 h and 24 h,all rats were sacrificed and lung tissues were obtained.The histopathological changes in lung tissues were evaluated by adopting hematoxylin-eosin staining,and wet/dry(W/D) was measured.The mRNA and protein levels of AQP1 and AQP5 in lung tissues were detected by adopting fluorogenic quantitative PCR (qPCR) and Western blot.Results Pathological stain showed that rats in control group had a normal lung tissue structure,and LPS made lung tissue edema,narrowing the alveolar cavity and inflammatory cell infiltration.CGRP attenuated the effect of LPS on rat's lung.The W/D ratio of lung tissue was significantly higher than that in the control group,and CGRP reduced the W/D ratio of lung tissue.qPCR showed that the mRNA levels of AQP1 and AQP5 from rats in ALI group (0.009 ±0.001 and 0.055 ±0.006)decreased compared with those in the control group (0.035±0.002 and 0.167 ±0.006) and CGRP group (0.024 ± 0.002 and 0.134 ± 0.012) (all P ＜ 0.001).Western blot results showed after 24 h injection of LPS,both AQP1 and AQP5 levels from ALI group (0.397 ± 0.041 and 0.215 ± 0.029) were significantly lower than those in the control group (0.850 ± 0.020 and 0.741 ± 0.032) (all P ＜ 0.001),and their levels in CGRP group (0.593-± 0.065 and 0.461 ± 0.039) were also lower than those in the control group,but higher than those in ALI group (all P ＜ 0.001).Conclusion CGRP can enhance AQP1 and AQP5 levels and reduce pulmonary edema,and it has a protective effect on rats with acute lung injury.

The early postoperation complications and treatments in 30 children with total anomalous pulmonary venous connection / 中国小儿急救医学

ObjectiveTo summarize the early postoperation complications and treatments in children with total anomalous pulmonary venous connection (TAPVC).MethodsThirty TAPVC children who were treated with corrective operation and transferred into PICU were collected.Patients were monitored routinely for electrocardiogram,blood pressure and SpO2.The routine treatment measures included mechanical ventilation,sedation,hemostasis,positive inotropic agents,diuresis,vasodilator,antibiotics and symptomatic treatment.Adrenaline or isoproterenol was used when low cardiac output syndrome appeared and temporary pacemaker was employed in the case of bradycardia.Alprostadil and sildenafil were added instantly after corrective operation when severe preoperative pulmonary hypertension or reactive postoperative pulmonary hypertension was present.ResultsThe early postoperation complication was found in 30 cases of TAPVC,which included 13 cases of pneumonia (43.3％ ),8 of arrhythmia (26.7％ ),7 of low cardiac output syndrome (23.3％),6 of respiratory failure (20.0％ ),4 of pulmonary hypertension ( 13.3％ ),3 of pulmonary edema or atelectasis( 10.0％ ) and 1 of pneumorrhagia ( 3.3％ ).Two cases died postoperatively.The interval of stay in PICU was 1 ～ 21 d and the mean time was (5.95 ± 4.94) d.ConclusionOccurrence of respiratory complications is high among early postoperative complications of TAPVC.Therefore,preventing pulmonary infection and maintaining pulmonary function should be viewed as the key points in early postoperative monitoring and managing.In addition,more attention should also be paid on correction of arrhythmia,prophylaxis and treatment of low cardiac output syndrome and pulmonary hypertension crisis,which may improve the postoperative survival rate and care quality of TAPVC.

Clinical features and changes of peripheral blood lymphocyte subsets in children with EBV-associated hemophagocytic syndrome / 中国小儿急救医学

Objective To summarize clinical features and changes of peripheral blood lymphocyte subsets in children with EBV-associated hemophagocytic syndrome. Methods Twenty children diagnosed with EBV-AHS were characterized by hemophagocytic syndrome and had the evidence of EBV infection.Clinical characteristics were analyzed and proportions of lymphocyte subsets of CD4+ ,CD8+, CD19+,CD16+CD56+ and CD4+/CD8+ in peripheral venous blood were determined by flow cytometry. Twenty healthy children matched in age and gender with these patients were selected as control. Results In all the diagnostic items of EBV-AHS, fever, decline of cells over two lineages in blood routine, enhanced lactate dehydrogenase ( ＞1 000 U/L) and ferritin ( ＞ 1 500 g/L),decreased high-density lipoprotein occurred in all the patients with an incidence of 100%. The percentages of CD8 + T and CD19 + B in children with EBV-AHS were higher than those in control group(53.70% ± 10.6% vs 27.05% ±8.22%,24.95% ±5.34% vs 11.85 % ± 4. 53 %, respectively), while levels of CD4 + T and CD16 + CD56 + NK cell were lower compared with control group (23.60% ±6. 42% vs 45.20% ±5.74% ,5.55% ±2. 87% vs 14. 70% ±4. 16% ,respectively ,P ＜ 0.01 ). Conclusion Disorder of cellular and humoral immunity happens in patients with EBV-AHS, which could be implicated in the pathogenesis and progression of EBV-AHS.

Isolation and primary culture of typeⅡ alveolar epithelial cells from fetal rat lung / 重庆医科大学学报

Objective:Todevelop the isolation and purification technology for typeⅡalveolar epithelial cells(AECⅡ)of fetal rat,in order to provide experimental means for the study of lung development or neonatal lung disease.Methods:Lung tissues of 19-day fetal rats were digested with trypsin and collagenase,then purified for AECⅡwith different centrifugal force and repeated attachment.Cell viability was evaluated by typran inclusion dying before plated into six-well flask.Growth status and shape of attached cells were observed with inverted phase contrast microscope.AECⅡwere identified by electron microscopy and its percentage was assessed by modified Papanicolaou dying and immunofluorescence,the latter aiming to detect expression of surfactant protein C(SPC)in AECⅡ.Results:The total amount of cells we harvested from 3 to5 fetal rat was(36?5)?106 with a viability of 98%?2%.Cells were like polygonal and connected like island under microscope.AECⅡwas ascertained by lamellar bodies found in cytoplasma under electron microscope and its percentage was 96%?3%identified by modified Papanicolaou dying,the same as the result by immunofluorescence for SPC.Conclusion:Highly Purified and viable AECⅡcould be achieved by our methods and the cell model could be used in further study.