A Fully Automated Multiplex Assay for Diagnosis of Lyme Disease with High Specificity and Improved Early Sensitivity.

Lyme borreliosis is a tick-borne disease caused by the Borrelia burgdorferisensu lato complex. Bio-Rad Laboratories has developed a fully automated multiplex bead-based assay for the detection of IgM and IgG antibodies to B. burgdorferi The BioPlex 2200 Lyme Total assay exhibits an improved rate of seropositivity in patients with early Lyme infection. Asymptomatic subjects from endemic and nonendemic origins demonstrated a seroreactivity rate of approximately 4% that was similar to other commercial assays evaluated in this study. Coupled to this result was the observation that the Lyme Total assay retained a high first-tier specificity of 96% while demonstrating a relatively high sensitivity of 91% among a well-characterized CDC Premarketing Lyme serum panel. The Lyme Total assay also performs well under a modified two-tier algorithm (sensitivity, 84.4 to 88.9%; specificity, 98.4 to 99.5%). Furthermore, the new assay is able to readily detect early Lyme infection in patient samples from outside North America.

Arca subcrenata Polypeptides Inhibit Human Colorectal Cancer HT-29 Cells Growth via Suppression of IGF-1R/Akt/mTOR Signaling and ATP Production.

Arca subcrenata Lischke, widely scattering offshore at neritic regions, is very popular on dining table due to its edible and medical functional meatball. This study aims to investigate the suppression of a polypeptide fraction from A. subcrenata (PAS) on human colorectal cancer HT-29 cells, and its underlying mechanism. The results showed that PAS inhibited the growth of HT-29 cells with an IC50 value of 117 µg/ml after 48 h treatment, and significantly suppressed the tumor growth in nude mice bearing-xenografted HT-29 cells at the dosage of 63 mg/kg, with little influence on normal colon cells and normal colonic mucosa. PAS was then inspiringly found to induce apoptosis and G2/M phase arrest in HT-29 cells. The effect mechanism was involved in the inhibition of IGF-1/IGF-1R signaling activation, which was responsible for inactivating downstream Akt/mTOR pathway. Immunofluorescence assay also showed that PAS could reduce phosphorylation of IGF-1R (Tyr1165/1166). IGF-1, an IGF-1R activator, could reverse the suppression of PAS on IGF-1R phosphorylation. Furthermore, PAS significantly inhibited ATP production of HT-29 cells both in vitro and in vivo. Our results provide positive evidence that A. subcrenata has the potential to be a candidate for the treatment of colorectal cancer.

RBM17 controls apoptosis and proliferation to promote Glioma progression.

The splicing factor SPF45 (RBM17) is a well-known component of the spliceosome that is involved in alternative splicing. RBM17 is frequently overexpressed in many tumors and plays a crucial role in cancer progression and drug resistance. However, the role of RBM17 in the development of glioma has not been thoroughly elucidated to date. In the present study, we found that RBM17 was overexpressed in glioma and that a high level of expression of RBM17 was closely associated with a poor prognosis in glioma patients. We investigated the effect of RBM17 on apoptosis, cell growth and cell cycle indexes and the activation of apoptosis signaling by shRNA in human U87 and U251 glioma cells. The downregulated expression of RBM17 mRNA was accompanied by the induction of cell cycle arrest, and apoptosis, reduced cell proliferation in the two cell lines, and reduced cell survival, as measured by the increased activation of caspase-3, caspase-9, and PARP (poly ADP-ribose polymerase). Furthermore, in subcutaneous U87 cell xenograft tumors in nude mice, intradermal administration of an shRNA targeting RBM17 significantly downregulated RBM17 expression in vivo and was accompanied by the suppressed growth of glioma. To the best of our knowledge, our results are the first to confirm that RBM17 functions in promoting cell proliferation, affecting the cell cycle, and inducing apoptosis in human glioma cells both in vitro and in vivo. These results indicate that RBM17 may be a therapeutic target in the clinical management of glioma.

Notch1 Signaling Activation Contributes to Adult Hippocampal Neurogenesis Following Traumatic Brain Injury.

BACKGROUND Neural stem cells are reported to exist in the hippocampus of adult mammals and are important sources of neurons for repair. The Notch1 signaling pathway is considered as one of the important regulators of neural stem cells, but its role in adult brains is unclear. We aimed to describe the role of Notch1 signaling in the adult rat hippocampus after traumatic brain injury. MATERIAL AND METHODS The model rats were randomly divided into 4 groups as follows: sham, sham-TBI, sham-Ad-TBI, and NICD-Ad-TBI. We used adenovirus-mediated gene transfection to upregulate endogenous NICD in vivo. Firstly, a TBI rat model was constructed with lateral fluid percussion. Then, the hippocampus was collected to detect the expression of Notch1 markers and stem cell markers (DCX) by Western blot analysis, immunohistochemistry, and immunofluorescence. The prognosis after TBI treatment was evaluated by the Morris Water Maze test. RESULTS First, we found the expression of NICD in vivo was significantly increased by adenovirus-mediated gene transfection as assessed by Notch1 immunofluorescence and Western blot analysis. Second, enhancing NICD stimulated the regeneration of neural stem cells in the DG of the adult rat brain following traumatic brain injury, as evaluated by DCX and NeuN double-staining. Furthermore, Notch1 signaling activation can promote behavioral improvement after traumatic brain injury, including spatial learning and memory capacity. CONCLUSIONS Our findings suggest that targeted regulation of Notch1 signaling may have a useful effect on stem cell transformation. Notch1 signaling may have a potential brain-protection effect, which may result from neurogenesis.

Expression of Stem Cell Markers and Dopamine D2 Receptors in Human and Rat Prolactinomas.

BACKGROUND Dopamine agonists (DAs) are the first-line treatment for prolactinomas. DAs primarily target the dopamine D2 receptor (D2R). Tumor stem-like cells (TSLCs) are associated with the tolerance to radiotherapy and chemotherapy. TSLCs have also been identified in pituitary adenomas. We aimed to characterize the expression pattern of stem cell markers and D2R in human and rat prolactinomas. MATERIAL AND METHODS Human prolactinoma specimens (n=14) were obtained from patients with surgical resection. The xenograft model of rat prolactinomas was generated by endermically injecting MMQ cells, HE and PRL were confirmed by immunohistochemical staining of tumor sections, and the expression of serum PRL was measured by ELISA. The expression of stem cell markers (CD133, Nestin, Oct4, and Sox2) and D2R in prolactinomas was detected by immunofluorescence. The proportion of CD133-expressing cells after DA treatment was evaluated by flow cytometry in vitro. RESULTS We found that a small subpopulation of cells expressing stem cell markers existed both in human and rat prolactinomas. Furthermore, the CD133-expressing cells showed negative D2R expression. Conversely, the D2R-expressing cells showed negative CD133 expression. The proportion of CD133-expressing cells in surviving tumor cells was significantly increased after DA treatment. CONCLUSIONS Our results confirmed the existence of cells expressing stem cell markers in human and rat prolactinomas. Additionally, the CD133-expressing cells might resist DA therapy due to the lack of D2R expression.

Antibacterial Activity of AI-Hemocidin 2, a Novel N-Terminal Peptide of Hemoglobin Purified from Arca inflata.

The continued emergence of antibiotic resistant bacteria in recent years is of great concern. The search for new classes of antibacterial agents has expanded to non-traditional sources such as shellfish. An antibacterial subunit of hemoglobin (Hb-I) was purified from the mantle of Arcainflata by phosphate extraction and ion exchange chromatography. A novel antibacterial peptide, AI-hemocidin 2, derived from Hb-I, was discovered using bioinformatics analysis. It displayed antibacterial activity across a broad spectrum of microorganisms, including several Gram-positive and Gram-negative bacteria, with minimal inhibitory concentration (MIC) values ranging from 37.5 to 300 µg/mL, and it exhibited minimal hemolytic or cytotoxic activities. The antibacterial activity of AI-hemocidin 2 was thermostable (25-100 °C) and pH resistant (pH 3-10). The cellular integrity was determined by flow cytometry. AI-hemocidin 2 was capable of permeating the cellular membrane. Changes in the cell morphology were observed with a scanning electron microscope. Circular dichroism spectra suggested that AI-hemocidin 2 formed an α-helix structure in the membrane mimetic environment. The results indicated that the anti-bacterial mechanism for AI-hemocidin 2 occurred through disrupting the cell membrane. AI-hemocidin 2 might be a potential candidate for tackling antibiotic resistant bacteria.

Diterpenoids from Wedelia prostrata and Their Derivatives and Cytotoxic Activities.

One new ent-kaurane diterpenoid, 11ß,16α-dihydroxy-ent-kauran-19-oic acid (1), together with eight known analogues 2 - 9 were isolated from the aerial parts of Wedelia prostrata. One of the acidic diterpenoids, kaurenoic acid (3), was converted to seven derivatives, 10 - 16. All compounds were evaluated for their cytotoxic activity in vitro against human leukemia (K562), liver (HepG-2), and stomach (SGC-7901) cancer cell lines. Only four kaurenoic acid derivatives, 13 - 16, with 15-keto and substitutions at C(19) position, exhibited notable cytotoxic activities on these tumor cell lines with IC50 value ranging from 0.05 to 3.71 µm. Compounds 10 - 12, with oxime on C(15) showed moderate inhibitory effects and compounds 1 - 9 showed no cytotoxicities on them. Structure-activity relationships were also discussed based on the experimental data obtained. The known derivative, 15-oxokaurenoic acid 4-piperdin-1-ylbutyl ester (17), induced typical apoptotic cell death in colon SW480 cells upon evaluation of the apoptosis-inducing activity by flow-cytometric analysis.

IL-13 receptor α2 stimulates human glioma cell growth and metastasis through the Src/PI3K/Akt/mTOR signaling pathway.

Glioma is a malignant tumor that affects all kinds of people all over the world. It demonstrates remarkable infiltrative and invasive features. The high expression of interleukin-13 receptor subunit alpha-2 (IL-13Rα2) reportedly plays a pivotal role in some cancers. However, whether IL-13Rα2 contributes to glioma remains unknown. This study demonstrates that IL-13Rα2 is significantly up-regulated in human glioma tissue samples. It is also associated with late stages of disease progression and diminished survival in glioma patients. Gain- and loss-of-function studies demonstrate that IL-13Rα2 promotes the growth, migration, and invasion of glioma cells. In addition, mechanistic investigations show that IL-13Rα2 activates Scr, phosphatidylinositol 3 kinase (PI3K), Akt, and mTOR. Also, restraining Scr in glioma cells attenuates the activation of Scr/PI3K/Akt/mTOR pathway by IL-13Rα2, whereas the silencing of Scr markedly rescues the pro-invasive effect of IL-13Rα2. In conclusion, our results suggest that the high expression of IL-13Rα2 is significantly associated with the growth and metastasis of human glioma cells via the Scr/PI3K/Akt/mTOR pathway, while IL-13Rα2 may be a potential therapeutic target for glioma treatment.

Antiproliferative and apoptosis-inducing activity of schisandrin B against human glioma cells.

BACKGROUND: Malignant glioma is the most devastating and aggressive tumour in the brain and is characterised by high morbidity, high mortality and extremely poor prognosis. The main purpose of the present study was to investigate the effects of schisandrin B (Sch B) on glioma cells both in vitro and in vivo and to explore the possible anticancer mechanism underlying Sch B-induced apoptosis and cell cycle arrest. METHODS: The anti-proliferative ability of Sch B on glioma cells were assessed by MTT and clony formation assays. Flow cytometric analysis was used to detect cell cycle changes. Apoptosis was determined by Hoechst 33342 staining and annexin V/PI double-staining assays. The mitochondrial membrane potential was detected by Rhodamine 123 staining. The in vivo efficacy of Sch B was measured using a U87 xenograft model in nude mice. The expressions of the apoptosis-related and cell cycle-related proteins were analysed by western blot. Student's t-test was used to compare differences between treated groups and their controls. RESULTS: We found that Sch B inhibited growth in a dose- and time-dependent manner as assessed by MTT assay. In U87 and U251 cells, the number of clones was strongly suppressed by Sch B. Flow cytometric analysis revealed that Sch B induced cell cycle arrest in glioma cells at the G0/G1 phase. In addition, Sch B induced glioma cell apoptosis and reduced mitochondrial membrane potential (ΔΨm) in a dose-dependent manner. Mechanically, western blot analysis indicated that Sch B induced apoptosis by caspase-3, caspase-9, PARP, and Bcl-2 activation. Moreover, Sch B significantly inhibited tumour growth in vivo following the subcutaneous inoculation of U87 cells in athymic nude mice. COCLUSIONS: In summary, Sch B can reduce cell proliferation and induce apoptosis in glioma cells and has potential as a novel anti-tumour therapy to treat gliomas.

Glial scar formation occurs in the human brain after ischemic stroke.

Reactive gliosis and glial scar formation have been evidenced in the animal model of ischemic stroke, but not in human ischemic brain. Here, we have found that GFAP, ED1 and chondroitin sulphate proteoglycans (CSPG) expression were significantly increased in the cortical peri-infarct regions after ischemic stroke, compared with adjacent normal tissues and control subjects. Double immunolabeling showed that GFAP-positive reactive astrocytes in the peri-infarct region expressed CSPG, but showed no overlap with ED1-positive activated microglia. Our findings suggest that reactive gliosis and glial scar formation as seen in animal models of stroke are reflective of what occurs in the human brain after an ischemic injury.

[Impact injuries of pedestrians: 90 cases study].

OBJECTIVE: To explore the relationship between pedestrian traffic accidents and the type of vehicles and summarize the characteristics. METHODS: Ninety cases of pedestrian traffic accidents were reviewed, and the relationship between the types of vehicles and the injuries (site, feature and severity) were analyzed. RESULTS: Different impact injuries were caused by different types of vehicles. The primary sites of the impact injuries depended on the body posture and the height of protruding parts of the front when the accident happened. The injury characteristics were related to the size, direction of acting force and contact surface. CONCLUSION: The analysis of position, feature, and severity of pedestrian injury can determine the type of injury vehicle.

Nature of back slopping kombucha fermentation process: insights from the microbial succession, metabolites composition changes and their correlations.

Kombucha, a fermented tea prepared with a symbiotic culture of bacteria and yeast (SCOBY), offers a unique and unpredictable home-brewed fermentation process. Therefore, the need for a controlled kombucha fermentation process has become evident, which requiring a thorough understanding of the microbial composition and its relationship with the metabolites produced. In this study, we investigated the dynamics of microbial communities and metabolites over a 12-day fermentation period of a conventional kombucha-making process. Our findings revealed similarities between the microbial communities in the early (0-2 days) and late (10-12 days) fermentation periods, supporting the principle of back-slopping fermentation. Untargeted metabolite analysis unveiled the presence of harmful biogenic amines in the produced kombucha, with concentrations increasing progressively throughout fermentation, albeit showing relatively lower abundance on days 8 and 12. Additionally, a contrasting trend between ethanol and caffeine content was observed. Canonical correspondence analysis highlighted strong positive correlations between specific bacterial/yeast strains and identified metabolites. In conclusion, our study sheds light on the microbial and metabolite dynamics of kombucha fermentation, emphasizing the importance of microbial control and quality assurance measures in the production process.

Notch4 is activated in endothelial and smooth muscle cells in human brain arteriovenous malformations.

Up-regulation of Notch4 was observed in the endothelial cells in the arteriovenous malformations (AVMs) in mice. However, whether Notch4 is also involved in brain AVMs in humans remains unclear. Here, we performed immunohistochemistry on normal brain vascular tissue and surgically resected brain AVMs and found that Notch4 was up-regulated in the subset of abnormal vessels of the brain AVM nidus, compared with control brain vascular tissue. Two-photon confocal images show that Notch4 was expressed not only in the endothelial but also in the smooth muscle cells of the vascular wall in brain AVMs. Western blotting shows that Notch4 was activated in brain AVMs, but not in middle cerebral artery of normal human brain, which was confirmed by immunostaining. Our findings suggest a possible contribution of Notch4 signalling to the development of brain AVMs in human.

Preliminary Investigation of Essentially Derived Variety of Tea Tree and Development of SNP Markers.

The continuous emergence of Essentially Derived Varieties (EDVs) in the process of tea tree breeding will endanger and affect the innovation ability and development potential of tea tree breeding. In this study, genotyping by sequencing (GBS) technology was used to screen high-quality genomic SNPs for the first time to investigate the derived relationships of 349 tea trees from 12 provinces in China. A total of 973 SNPs uniformly covering 15 tea tree chromosomes with high discrimination capacity were screened as the core SNP set. A genetic similarity analysis showed that 136 pairs of tea trees had a genetic similarity coefficient (GS) > 90%, among which 60 varieties/strains were identified as EDVs, including 22 registered varieties (19 were indisputably EDVs). Furthermore, 21 SNPs with 100% identification of 349 tea trees were selected as rapid identification markers, of which 14 SNP markers could be used for 100% identification of non-EDV. These results provide the basis for the analysis of the genetic background of tea trees in molecular-assisted breeding.

Artificial intelligence differentiates abdominal Henoch-Schönlein purpura from acute appendicitis in children.

OBJECTIVE: This study aims to construct an artificial intelligence (AI) model capable of effectively discriminating between abdominal Henoch-Schönlein purpura (AHSP) and acute appendicitis (AA) in pediatric patients. METHODS: A total of 6965 participants, comprising 2201 individuals with AHSP and 4764 patients with AA, were enrolled in the study. Additionally, 53 laboratory indicators were taken into consideration. Five distinct artificial intelligence (AI) models were developed employing machine learning algorithms, namely XGBoost, AdaBoost, Gaussian Naïve Bayes (GNB), MLPClassifier (MLP), and support vector machine (SVM). The performance of these prediction models was assessed through receiver operating characteristic (ROC) curve analysis, calibration curve assessment, and decision curve analysis (DCA). RESULTS: We identified 32 discriminative indicators (p < .05) between AHSP and AA. Five indicators, namely the lymphocyte ratio (LYMPH ratio), eosinophil ratio (EO ratio), eosinophil count (EO count), neutrophil ratio (NEUT ratio), and C-reactive protein (CRP), exhibited strong performance in distinguishing AHSP from AA (AUC ≥ 0.80). Among the various prediction models, the XGBoost model displayed superior performance evidenced by the highest AUC (XGBoost = 0.895, other models < 0.89), accuracy (XGBoost = 0.824, other models < 0.81), and Kappa value (XGBoost = 0.621, other models < 0.60) in the validation set. After optimization, the XGBoost model demonstrated remarkable diagnostic performance for AHSP and AA (AUC > 0.95). Both the calibration curve and decision curve analysis suggested the promising clinical utility and net benefits of the XGBoost model. CONCLUSION: The AI-based machine learning model exhibits high prediction accuracy and can differentiate AHSP and AA from a data-driven perspective.

Finite Element Parametric Design of Hallux Valgus Orthosis Based on Orthogonal Analysis.

OBJECTIVE: To design appropriate orthosis for hallux valgus, a difficult foot condition that affects a quarter of the body's bones, we need to clarify the numerical biomechanical features, which have not been established in previous biomechanical studies. Therefore, we constructed a finite element model of the bunion foot to investigate the orthopaedic force compensation mechanism. METHODS: A patient with moderate hallux valgus was recruited. CT imaging data in DICOM format were extracted for three-dimensional foot model reconstruction. In conjunction with the need for rapid design of bunion orthosis, a metatarsal force application sizing method based on an orthogonal test design was investigated. The orthogonal test design was used to obtain the hallux valgus angle (HVA) and the inter metatarsal angle (IMA) data for different force combinations. Based on the extreme difference analysis and analysis of variance of the test results, the influence of different force combinations on the bunion angle was quickly determined. RESULTS: The results showed that the stress concentration occurred mainly in the first metatarsal bone. The distribution trend was in the medial and lateral middle of the bone and gradually decreased to the dorsal base of the bone body. The greatest stress occurs in the cartilage between the phalanges and metatarsals. In 25 groups of simulation experiments, HVA was reduced from 27.7° to 13°, and IMA was reduced from 12.5° to 7.3°. CONCLUSION: Applying detailed orthopaedic force collocation to the first metatarsal column can effectively restore the mechanics and kinematics of hallux valgus, and provide a reference for the treatment of bunion valgus and the design of orthopaedic devices.

Label-free optical metabolic imaging of adipose tissues for prediabetes diagnosis.

Rationale: Prediabetes can be reversed through lifestyle intervention, but its main pathologic hallmark, insulin resistance (IR), cannot be detected as conveniently as blood glucose testing. In consequence, the diagnosis of prediabetes is often delayed until patients have hyperglycemia. Therefore, developing a less invasive diagnostic method for rapid IR evaluation will contribute to the prognosis of prediabetes. Adipose tissue is an endocrine organ that plays a crucial role in the development and progression of prediabetes. Label-free visualizing the prediabetic microenvironment of adipose tissues provides a less invasive alternative for the characterization of IR and inflammatory pathology. Methods: Here, we successfully identified the differentiable features of prediabetic adipose tissues by employing the metabolic imaging of three endogenous fluorophores NAD(P)H, FAD, and lipofuscin-like pigments. Results: We discovered that 1040-nm excited lipofuscin-like autofluorescence could mark the location of macrophages. This unique feature helps separate the metabolic fluorescence signals of macrophages from those of adipocytes. In prediabetes fat tissues with IR, we found only adipocytes exhibited a low redox ratio of metabolic fluorescence and high free NAD(P)H fraction a1. This differential signature disappears for mice who quit the high-fat diet or high-fat-high-sucrose diet and recover from IR. When mice have diabetic hyperglycemia and inflamed fat tissues, both adipocytes and macrophages possess this kind of metabolic change. As confirmed with RNA-seq analysis and histopathology evidence, the change in adipocyte's metabolic fluorescence could be an indicator or risk factor of prediabetic IR. Conclusion: Our study provides an innovative approach to diagnosing prediabetes, which sheds light on the strategy for diabetes prevention.

Expression of dopamine 2 receptor subtype mRNA in clinically nonfunctioning pituitary adenomas.

Dopamine receptor agonists (DAs) can reduce hormone release and tumor mass in the majority of prolactinomas, whereas such effects are controversial in clinically nonfunctioning pituitary adenomas (NFPAs). Whether expression of dopamine 2 receptor (D2R) is different in subgroups of NFPAs has not been fully elucidated. We assessed and compared D2R subtype (long: D2L and short: D2S) mRNA levels in subgroups of NFPAs by real-time reverse transcriptase polymerase chain reaction (RT-PCR). For both D2L and D2S mRNA, there were no significant differences among them. Only 21.6% of NFPAs showed relatively high D2R mRNA levels; furthermore, histopathological subtypes of those cases with relatively high D2R expression were gonadotropinomas and null-cell adenomas. These data suggest that DAs are effective only for a small proportion of NFPAs, and relatively high D2R expression may more possibly happen to a subset of gonadotropinomas and null-cell adenomas.

[Targeted therapy of malignant glioma by a chimeric fusion toxin composed of IL-13 and Pseudomonas exotoxin in vitro].

OBJECTIVE: To examine the antitumor activity of IL-13PE38 on solid malignant glioma cells in vitro and to investigate its relationship between the antitumor activity of IL-13PE38 and the expression level of IL-13Rα2 in malignant glioma. METHODS: Ten fresh tissues of anaplastic glioma and 11 fresh tissues of glioblastoma multiforme were obtained during craniotomy at First Affiliated Hospital, Wenzhou Medical College between June 2009 and December 2010. All fresh glioma cells were cultured in vitro with IL-13PE38. Then the cytotoxicity of IL-13PE38 was determined by colorimetric MTS proliferation assay and the SR (survival rate) calculated. The expression level of IL-13Rα2 was studied by immunohistochemical SABC method in 21 cases of malignant glioma. And the value of integrated optical density (IOD) was examined by computer assisted pathological image analysis system. The correlation between the IOD of IL-13Rα2 and the SR of malignant glioma cells was also studied. RESULTS: (1) There were strongly positive expression of IL-13Rα2 in most cases (19/21, 90%). And the expression level of IL-13Rα2 in glioblastoma multiforme was higher than the expression level of IL-13Rα2 in anaplastic glioma (P < 0.05). (2) As the fresh malignant glioma cells were cultured with IL-13PE38 of same concentration, the number of surviving cells decreased in different degrees. The survival rate of 14 cases were < 70% and 9 cases < 50%. And the survival rate of anaplastic glioma cells was higher than that of glioblastoma multiforme cells (P < 0.05). (3) The IOD of IL-13Rα2 and the SR of malignant glioma cells were strongly negatively correlated (r = -0.093, P < 0.01). CONCLUSION: A low concentration of IL-13PE38 shows a high level of cytotoxicity for solid malignant glioma cells. And its cytotoxic efficiency depends on the expression level of IL-13Rα2.

Development and Validation of a Differential Diagnosis Model for Acute Appendicitis and Henoch-Schonlein Purpura in Children.

Objective: To study and develop a predictive model for the differential diagnosis of acute appendicitis (AA) and Henoch-Schonlein purpura (HSP) in children and to validate the model internally and externally. Methods: The complete data of AA and HSP cases were retrospectively analyzed and divided into internal and external verification groups. SPSS software was used for single-factor analysis and screening of independent variables, and R software was used for the development and verification of the diagnostic model. Lasso regression analysis was used to screen predictors and Lasso-logistic regression model was constructed, and K-fold cross-validation was used for the internal verification. In addition, nonfever patients were selected for model development and validation in the same way. Receiver operating characteristic (ROC) curves and calibration curves were drawn, respectively, to evaluate the 2 models. Results: Internal development and validation of the model showed that fever, neutrophil ratio (NEUT%), albumin (ALB), direct bilirubin (DBIL), C-reactive protein (CRP), and K were predictive factors for the diagnosis of HSP. The model was presented in the form of a nomogram, and the area under ROC curve of the development group and verification group was 0.9462 (95% confidence interval [CI] = 0.9402-0.9522) and 0.8931 (95% CI = 0.8724-0.9139), respectively. In the model of patients without fever, NEUT%, platelets (PLT), ALB, DBIL, alkaline phosphatase (ALP), CRP, and K were predictive factors for the diagnosis of HSP, and the area under ROC curve of the development group and verification group was 0.9186 (95% CI = 0.908-0.9293) and 0.8591 (95% CI = 0.8284-0.8897), respectively. Conclusion: In this study, 2 diagnostic models were constructed for fever or not, both of which had good discrimination and calibration, and were helpful to distinguish AA and HSP in children.