ObjectiveTo investigate the clinical characteristics and risk factors of Mycoplasma pneumoniae pneumonia （MPP） in children based on a dual classification integrating imaging features and clinical severity. MethodsMedical records of 2 054 pediatric patients with MPP were retrospectively analyzed. The cohort was stratified into severe consolidation （n=253）， severe non-consolidation （n=118）， non-severe consolidation （n=393）， and non-severe non-consolidation groups （n=1 290） based on clinical and radiological findings. Inter group data and characteristics were compared and multiple regression analysis was conducted to construct a prediction model for severe consolidation group. ResultsSignificant differences were observed among the groups in terms of age， duration of fever， length of hospital stay， presence of pulmonary rales， inflammatory markers ［C-reactive protein （CRP） and lactate dehydrogenase （LDH）］， the use of hormones， and bronchoscopic treatment （all P < 0.05）. Compared with the severe non-consolidation group， non-severe consolidation group， and non-severe non-consolidation group， children in severe consolidation group exhibited the longest duration of fever ［8 （6， 11） days vs 6 （2， 9）， 7 （6， 9） and 6 （3， 8） days， respectively］ and the longest length of hospital stay ［7 （5， 8） days vs 6 （5， 8）， 6 （5， 8） and 6 （4， 7） days， respectively］. They also had the highest incidence of reduced breath sounds ［34 cases （13.4%） vs 2 cases （1.7%）， 29 cases （7.4%） and 13 cases （1.0%）， respectively］ and a substantially higher rate of coinfections， particularly viral infections ［63 cases （24.9%） vs 23 cases （19.5%）， 60 cases （15.3%） and 190 cases （14.7%）， respectively］. Multivariate analysis indicated that the independent risk factors for severe MPP （SMPP） were age > 4.5 years， length of hospital stay > 6.5 days， reduced breath sounds， neutrophil-to-lymphocyte ratio （NLR） > 1.66， LDH > 370.5 U/L， CRP > 9.5 mg/L， and coinfection with viruses. Reduced breath sounds （OR = 5.58， 95% CI： 2.45 - 12.69） and coinfection with bacteria （OR = 3.11， 95% CI： 1.43 - 6.75） were identified as the most significant risk factors for pulmonary consolidation in non-severe MPP children. Additionally， reduced breath sounds， coinfection with viruses， LDH > 365.5 U/L， and CRP > 32.1 mg/L were risk factors for severe pneumonia in children with pulmonary consolidation. For non-consolidation MPP children， the presence of pulmonary dry rales （OR = 2.28， 95% CI： 1.46 - 3.56） was the primary independent risk factor for the development of severe pneumonia. ConclusionThe chest imaging findings of MPP are associated with clinical severity， and the risk factor model constructed based on this imaging-clinical classification can assist in achieving precise hierarchical diagnosis and treatment in clinical practice.

Objective : To investigate the diagnostic value of plasma calprotectin in childern with refractory mycoplasma pneumoniae pneumonia(RMPP). Methods : A multicenter, prospective cohort study was conducted, enrolling 228 children with mycoplasma pneumoniae pneumonia(MPP). Among these, 177 cases were diagnosed with general mycoplasma pneumoniae pneumonia(GMPP), while the remaining 51 cases were RMPP. Plasma was collected at the time of admission of the children in both groups, and calprotectin levels were measured. A one-way difference analysis was performed on the blood test indexes of the children in the two groups, and the difference variables withP<0.05 between the two groups were included in a multifactorial logistic regression to analyze the risk factors for the progression of GMPP to RMPP. The differential diagnostic value of plasma calprotectin for GMPP and RMPP was analyzed by the receiver operating characteristic(ROC) curves. Results : Univariate analysis showed that plasma calprotectin levels were significantly higher in the RMPP group than those in the GMPP group, and the difference was statistically significant(P<0.05). Logistic regression analysis showed that plasma calprotectin was an independent risk factor for RMPP(OR=1.323,P<0.001), ROC curve analysis showed that plasma calprotectin had a higher diagnostic value for the differential diagnosis of GMPP and RMPP(AUC =0.839), and its combination with C-reactive protein and albumin could significantly improve the diagnostic efficiency. Conclusion Plasma calprotectin has good clinical value for the diagnosis of RMPP.

Objective : To investigate the efficacy of standardized allergen subcutaneous immunotherapy (SCIT) in children with asthma sensitized to single dust mite allergens versus multiple allergens and to assess the safety of SCIT. Methods : 62 children with confirmed allergic asthma who received standardized allergen SCIT were retro⁃ spectively analyzed and divided into the monosensitized group (dust mite results≥ + + + ) and the polysensitized group (dust mite results ≥ + + + combined with other positive allergens) according to the results of skin pricktest , we observed the changes of pulmonary function , medication score and visual analog scale (VAS) scores , children asthma control test (C - ACT) scores , asthma control questionnaire (ACQ) scores before and after treatment in both groupsand compared the efficacy of the two groups. The incidence of local and systemic adverse effects was recorded during treatment in all children to assess the safety of SCIT. Results : Standardized allergen SCIT treatmentimproved lung function parameters , medication scores and VAS scores , C ⁃ACT scores , ACQ scores in both the monosensitized and polysensitized groups , with statistically significant differences before and after treatment (P < 0. 05) . In comparison between the two groups , lung function parameters [forced expiratory flow at 50% vital capacity(FEF50% ) , maximum midexpiratory flow(MMEF)] , medication scores , C ⁃ACT scores and ACQ scores improved significantly in the monosensitized group compared with the polysensitized group after treatment ( P <0. 001) . 62 patients received a total of 2 606 injections during the treatment of SCIT , 6 children had a total of 10 local adverse reactions and 3 children had 3 mild to moderate systemic adverse reactions , with an incidence of 0. 38% for local adverse reactions and 0. 12% for systemic adverse reactions. Conclusion The children with asthma in both the monosensitized group and polysensitized group achieved significant and safe clinical outcomes under standardized allergen SCIT. The children in the monosensitized group had more obvious clinical effects than the polysensitized group under standardized allergen SCIT.

OBJECTIVESTo investigate the expression of macrophage migration inhibitory factor (MIF) mRNA in Schwann cells after peripheral nerve injury and roles of Schwann cells and MIF in macrophages activation and nerve regeneration.

METHODSFifty SD rats were divided into 10 groups. One group served as normal control. The rest were anesthetized with 3% sodium pentobarbital (30 - 60 mg/kg, i.p) and sciatic nerves were transected distal to the obturator tendon respectively 1 h, 12 h, 1 d, 3 d, 7 d, 10 d, 14 d, 17 d and 21 d before being killed. Sciatic nerves were resected and connective tissues excised. Schwann cells were obtained by digesting the nerve tissues with trypsin and collagenase. RNA was isolated and reverse-transcription-polymerase chain reaction (RT-PCR) was carried out. cDNA was analyzed by automatic system and the parameters were assessed to define the status of MIF mRNA expression in different groups.

RESULTSThe level of MIF mRNA started to increase 12 h after the nerve transection. The level remained high from day 7 up to 10 after the injury. During the period from days 10 to 21, MIF mRNA decreased slowly to the pre-transection level.

CONCLUSIONAfter peripheral nerve injury, Schwann cells can secrete MIF which may play a pivotal role as an immunomodulatory cytokine in macrophage activation and inflammatory reaction.

Animals ; Female ; Macrophage Migration-Inhibitory Factors ; genetics ; Male ; Peripheral Nerve Injuries ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction ; Schwann Cells ; metabolism