Targeting the aryl hydrocarbon receptor with FICZ regulates IL-2 and immune infiltration to alleviate Hashimoto's thyroiditis in mice.

Hashimoto's thyroiditis (HT) is the most frequent autoimmune disorder. Growing work points to the involvement of aryl hydrocarbon receptor (AhR), a ligand-dependent transcription factor, in the regulation of immune homeostasis. However, the roles of AhR and its ligands in HT remains unclear. In this study, we leveraged public human database analyses to postulate that the AhR expression was predominantly in thyroid follicular cells, correlating significantly with the thyroid infiltration levels of multiple immune cells in HT patients. Using a thyroglobulin-induced HT mouse model and in vitro thyroid follicular epithelial cell cultures, we found a significant downregulation of AhR expression in thyrocytes both in vivo and in vitro. Conversely, activating AhR by FICZ, a natural AhR ligand, mitigated inflammation and apoptosis in thyrocytes in vitro and conferred protection against HT in mice. RNA sequencing (RNA-seq) of thyroid tissues indicated that AhR activation moderated HT-associated immune or inflammatory signatures. Further, immunoinfiltration analysis indicated that AhR activation regulated immune cell infiltration in the thyroid of HT mice, such as suppressing cytotoxic CD8+ T cell infiltration and promoting anti-inflammatory M2 macrophage polarization. Concomitantly, the expression levels of interleukin-2 (IL-2), a lymphokine that downregulates immune responses, were typically decreased in HT but restored upon AhR activation. In silico validation substantiated the binding interaction between AhR and IL-2. In conclusion, targeting the AhR with FICZ regulates IL-2 and immune infiltration to alleviate experimental HT, shedding new light on the therapeutic intervention of this prevalent disease.

Integrated Analysis of miRNAs and Gene Expression Profiles Reveals Potential Biomarkers for Osteoarthritis.

Purpose: Currently, the early diagnosis and treatment of osteoarthritis (OA) remain a challenge. In the present study, we attempted to explore potential biomarkers for the diagnosis and treatment of OA. Methods: The differentially expressed genes (DEGs) were identified based on three mRNA datasets of synovial tissues for OA patients and normal controls downloaded from the Gene Expression Omnibus (GEO) database. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were used for evaluating gene function related categories. Then, miRNA sequencing was performed for differentially expressed miRNAs' identification. Finally, weighted gene co-expression network analysis (WGCNA) was performed for genes detected by the three mRNA datasets and a competing endogenous RNA (ceRNA) network with DEGs and differentially expressed microRNAs (miRNAs) was constructed for central genes identification. In addition, the relationship between central gene expression and immune infiltration was analyzed, and the candidate agents for OA were predicted based on the Connectivity Map database. Quantitative RT-PCR (qRT-PCR), Western blotting analysis, and immunofluorescent staining were performed to validate the expression levels of differentially expressed miRNAs and differentially expressed target genes in normal and OA tissues and chondrocytes. MiRNA-mRNA network was also validated in chondrocytes in vitro. Results: A total of 259 DEGs and 26 differentially expressed miRNAs were identified, among which 94 miRNA-mRNA interactions were predicted. The brown module in WGCNA was most closely correlated with the clinical traits of OA. After overlapping the brown module genes with miRNA-mRNA pairs, 27 miRNA-mRNA pairs were obtained. A ceRNA network was constructed with 5505 lncRNA-miRNA-mRNA interactions. B-cell translocation gene 2(BTG2), Abelson-related gene (ABL2), and vascular endothelial growth factor A (VEGFA) were identified to be the central genes with good predictive performance, which were significantly correlated with immune cell infiltration in OA, reflected by declined activated dendritic cells (aDCs), and elevated contents of B cells, macrophages, neutrophils, and T helper cells. Anisomycin, MG-132, thapsigargin, and lycorine were predicted to be the potential candidate agents for OA intervention. In vitro, the expression levels of differentially expressed miRNAs and biomarkers identified in the present study were consistent with the results obtained in normal or OA knee cartilage tissues and chondrocytes. Furthermore, BTG2 was identified to be negatively regulated by miR-125a-5p. Conclusion: BTG2, ABL2, and VEGFA can be regarded as potential predictive and treatment biomarkers for OA, which might guide the clinical therapy of OA.

Free bone grafting improves clinical outcomes in anterior shoulder instability with bone defect: a systematic review and meta-analysis of studies with a minimum of 1-year follow-up.

BACKGROUND: Evidence on the efficacy and safety of the free bone grafting in treating anterior shoulder instability is limited. The purpose of this study was to systematically evaluate the clinical and imaging results of free bone grafting in treating anterior shoulder instability with glenoid bone defect and to explore the incidence of complications in clinically relevant subgroups. METHODS: This systematic review was conducted per PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. The PubMed, Embase, and Cochrane Library databases were searched up to January 29, 2021, for studies that had reported on free bone grafting in treating anterior shoulder instability with glenoid bone defect with a minimum of 1-year follow-up. Two researchers independently screened studies and extracted data. A random-effects model was used to pool data on clinical function scores, imaging results, and incidence of complications (recurrent instability and non-instability-related complications). Meta-regression analysis was used to evaluate the incidence of complications in different subgroups and investigate the sources of heterogeneity. RESULTS: A total of 29 studies were included in the meta-analysis, comprising 840 patients (845 shoulders) with average ages ranging from 21 to 34.6 years. Compared with preoperatively, free bone grafting increased the postoperative Rowe score, American Shoulder and Elbow Surgeons score, Constant score, Subjective Shoulder Value, and Oxford Shoulder Instability Score by 53.16, 31.80, 20.81, 38.63, and 4.07 points, respectively, and reduced the visual analog scale pain score by 3 points on average. During the postoperative follow-up period, the rates of return to sport and return to preoperative levels were 84.2% and 73.1%, respectively. The imaging results showed that the free bone healing rate was 98.9% and the incidence of osteoarthritis was 10.9%. The incidence rates of recurrent instability and non-instability-related complications were 3.4% and 5.6%, respectively. Meta-regression analysis showed no evidence of effect modification by the year, follow-up time, proportion of male patients, autograft or allograft, and arthroscopy or open surgery on the incidence of complications. Subgroup analysis showed that the incidence rates of recurrent instability for open surgery, arthroscopy, allograft, autograft, Latarjet revision, and non-bone block revision were 4.1%, 2.3%, 1.5%, 4.4%, 10.3%, and 3.5%, respectively. CONCLUSION: The application of free bone grafting in treating anterior shoulder instability with glenoid bone defect can effectively improve shoulder joint function and is associated with a high return-to-sport rate and a low overall recurrence rate, but there were some differences in the complications of recurrent instability and non-instability-related complications among the subgroups. Given that these results need to be confirmed via head-to-head comparisons, we recommend that future clinical and biomechanical studies focus on comparing and investigating the advantages and disadvantages of different surgical approaches, thus providing a basis for orthopedic surgeons to make reliable choices.

Excellent outcomes with Oxford Uni-compartmental knee arthroplasty in anteromedial osteoarthritis patients (≤60 years) at mid-term follow-up.

BACKGROUND: The use of Oxford uni-compartmental knee arthroplasty (UKA) has rapidly increased worldwide,however,the relevance of younger patients for postoperative function after Oxford UKA remains unclear. The main purpose of our study is to clarify the effectivemess of Oxford UKA in the younger Chinese patients with anteromedial osteoarthritis (AMOA). METHODS: We retrospectively enrolled 252 consecutive patients who underwent Oxford UKA for AMOA with a minimum follow-up of 5 years between March 2013 and December 2016. The patients were divided into the younger (≤60 years) and elderly (> 60 years) age groups. The demographic data and surgery variables were recorded and compared. Patient satisfaction grade, range of motion (ROM), Oxford knee score (OKS), Hospital for Special Surgery (HSS) score, Western Ontario and McMaster (WOMAC) Universities Osteoarthritis Index score and postoperative complications were recorded. The 5-year survival of the implants were also compared with TKA revision as the endpoint. RESULTS: A total of 252 consecutive patients were recruited, including 96 aged 60 years or less and 156 aged over 60 years. The mean follow-up duration in the younger and elderly groups were 73.6 months (SD,standard deviation, 4.1) and 74.7 months (SD 6.2) respectively. Patient satisfaction rate was high in both groups (P = 0.805). Furthermore, no significant differences were observed in postoperative ROM(P = 0.299), OKS(P = 0.117), HSS(P = 0.357) and WOMAC scores(P = 0.151) between the younger and elderly groups (P>0.05). However, the incidence of joint stiffness (P = 0.033) and delayed wound dehiscence (P = 0.026) were significantly different between both groups. Five-year implant survival without revision were also similar in both groups (96.9% vs 97.4%, P = 0.871), and that for the entire cohort was 97.2% (95% CI 95.4-99.6). CONCLUSION: Oxford UKA for AMOA demonstrated favorable results in younger patients aged ≤60 years at a minimum 5-year follow-up in terms of patient satisfaction, functional outcomes, implant survival and postoperative complications. Therefore, younger patients might not be considered as an absolute contraindication to Oxford UKA.

Directional immobilization of antibody onto magnetic nanoparticles by Fc-binding protein-assisted photo-conjugation for high sensitivity detection of antigen.

Immobilized antibodies with site-specific, oriented, and covalent pattern are of great significance to improve the sensitivity of solid-phase immunoassay. Here, we developed a novel antibody conjugation strategy that can immobilize antibodies in a directional and covalent manner. In this study, an IgG-Fc binding protein (Z domain) carrying a site-specific photo-crosslinker, p-benzoyl-L-phenylalanine, and a single C-terminal cysteine (Cys) handle was genetically engineered. Upon UV irradiation, the chimeric protein enables the Cys handle to couple with the native antibody in Fc-specific and covalent conjugation pattern, resulting in a novel thiolated antibody. Thus, an approach for the covalent, directional immobilization of antibodies to maleimide-modified magnetic nanoparticles (MNPs) was developed on the basis of the crosslinking between sulfhydryl and maleimide groups. The antibody-conjugated MNPs were applied in MNP-based enzyme-linked immunosorbent assay (ELISA) for the detection of carcinoembryonic antigen. The MNP-based ELISA presented a quantification linear range of 0.1-100 ng mL-1 and detection limit of 0.02 ng mL-1, which was approximately 100 times more sensitive than the traditional microplate ELISA (2.0 ng mL-1). Thus, the proposed antibody immobilization approach can be used in surface functionalization for the sensitive detection of various biomarkers.

A solid-contact Ca2+-selective electrode based on an inorganic redox buffer of Ag@AgCl/1-tetradecyl-3-methylimidazolium chloride as ion-to-electron transducer.

For construction of solid-contact ion-selective electrodes (SC-ISEs), ion-to-electron transducers based on the redox capacitance transduction mechanism are currently restricted to organic materials. Exploring inorganic nanomaterials with high redox buffer capacities as intermediate layers for SC-ISEs would offer another alternative. Herein, a solid-contact calcium ion-selective electrode (SC-Ca2+-ISE) with a new inorganic redox buffer-Ag@AgCl/1-tetradecyl-3-methylimidazolium chloride (TMMCl) as the ion-to-electron transducer is presented. In this system, the predominant component core-shell Ag@AgCl nanoparticles with diameters ranging from 30 to 100 nm can be prepared through a two-step process. An ionic liquid TMMCl is used to offer a source of free Cl-. The developed SC-Ca2+-ISE exhibits a near Nernstian slope of 28.3 mV/decade for Ca2+ in the range of 10-6 - 10-2 M. By using of the inorganic redox buffer, the SC-Ca2+-ISE has a smaller impedance and higher capacitance than the coated-wire electrode, which guarantees a stable potential response. Additionally, the proposed SC-Ca2+-ISE shows excellent resistances to interferences of light, O2 and CO2, with a reduced water layer formed between the ion-selective membrane and the underlying solid contact. The developed inorganic redox buffer of Ag@AgCl/TMMCl can be effectively used as a new ion-to-electron transducer for construction of solid contact ISEs.

Type 2 diabetes can undermine driving performance of middle-aged male drivers through its deterioration of perceptual and cognitive functions.

It has been widely agreed that it is risky for patients with diabetes to drive during hypoglycemia. However, driving during non-hypoglycemia may also bring certain safety hazards for some patients with diabetes. Based on previous studies on diabetes-related to early aging effect, as well as gender differences in health belief and driving behavior, we have hypothesized that middle-aged male drivers with type 2 diabetes, compared with the control healthy ones, may experience a decline in driving performance without awareness. And the decline is caused by impaired perceptual and cognitive driving-related functions. To verify these hypotheses, we recruited 56 non-professional male drivers aged between 40 and 60 (27 patients with type 2 diabetes and 29 healthy controls) to perform a simulated car-following task and finish behavioral tests of proprioception, visual search, and working memory abilities during non-hypoglycemia. They also reported their hypoglycemia experience and perceived driving skills. We found that the patients had equal confidence in their driving skills but worse driving performance as shown in larger centerline deviation (t = 2.83, p = .006), longer brake reaction time (t = 3.77, p = .001) and shorter minimum time-to-collision (t = -3.27, p = .002). Such between-group differences in driving performance could be fully mediated by proprioception, visual search ability, and working memory capacity but not by hypoglycemia experience. Regarding the effect sizes of the mediation, the visual search ability played the most important role, and then followed the working memory and the proprioception. This initial study provides original and first-hand evidence demonstrating that the middle-aged male drivers with type 2 diabetes have deteriorated driving performance, but they are unaware of it. We will also discuss the possible measures to identify people of the highest risk and improve their safety awareness by using the findings of the current study.

Looking for an optimal pedal layout to improve the driving performance of patients with diabetic peripheral neuropathy.

Diabetes can undermine people's ability to drive safely, but most previous studies have focused on its deterioration of the central nervous system. This study sought to investigate how diabetic peripheral neuropathy (DPN), a common complication of diabetes characterized by reduced sensitivity of the limbs, can influence people's braking behavior and other safety-related measures of driving. In addition, it also tested how such a deteriorating effect can be reduced by using certain pedal layout designs. In total, 29 healthy drivers and 31 drivers of type 2 diabetes matched in demographic variables were invited to participate in this study. The participants with type 2 diabetes (they are from here on out referred to as "patients")were then split into two subgroups based on the severity of DPN using the median of the Semmes-Weinstein monofilaments Examination (SWME) scores. All three groups of participants finished a series of vehicle-pedestrian conflict tasks in a driving simulator using nine different types of pedal layouts. These layouts varied in the lateral distance between the accelerator and the brake (45 mm, 60 mm, and 75 mm) and the width of brake pedals (50 mm, 70 mm, 90 mm). The results showed that patients with serious DPN had longer brake reaction times (BRT) and shorter minimum distance-to-collision (DTC) as compared to the other two groups. However, the effects of such a disadvantage varied across different pedal layouts. When the accelerator-brake distance was 45 mm, patients with serious DPN showed no compromised driving performance as compared to other two groups. In conclusion, we found the DPN could undermine driving performance of participants with type 2 diabetes, and a closer accelerator-brake lateral distance (45 mm) may be an optimal choice for them to counteract such a negative influence.

A solid-contact potassium-selective electrode with MoO2 microspheres as ion-to-electron transducer.

A solid-contact ion-selective electrode (SC-ISE) for potassium with MoO2 microspheres as ion-to-electron transducer is described. MoO2 microsphers can be synthesized via the reduction of MoO3 nanobelts in an isopropanol solvent with a mild process, and the obtained MoO2 microspheres have been characterized by X-ray diffraction and field-emission scanning electron microscopy. With the application of MoO2 microspheres, the newly fabricated SC-ISE for K+ exhibits a stable and rapid potential response. A near Nernstian slope of 55 mV/decade to potassium activities in the range of 10-5 ‒ 10-3 M is found and the detection limit is 10-5.5 M. Impedance spectra and chronopotentiometry results show that a smaller resistance together with a larger double layer capacitance is guaranteed due to the introduction of the intermediate layer of MoO2 microspheres. Additionally, light, O2 and CO2 do not induce significant influences to the present SC-ISE, and a reduced water layer between the ion selective membrane and the underlying conductor is formed. Thus, it is clear that MoO2 microspheres, as metallic analogues, can be used as a good candidate for the new type of transducing layer in SC-ISEs.

Prognostic Factors and Postoperative Recurrence of Calculus Following Small-Incision Sphincterotomy with Papillary Balloon Dilation for the Treatment of Intractable Choledocholithiasis: A 72-Month Follow-Up Study.

OBJECTIVE: To evaluate the recurrence of common bile duct stones and risk factors for recurrence following routine endoscopic sphincterotomy (EST) versus small-incision endoscopic sphincterotomy plus endoscopic papillary balloon dilation (EST-EPBD). METHODS: Three hundred patients who were hospitalized between June 2007 and June 2008 with common bile duct stones >10 mm in diameter were randomly assigned to the EST or EST-EPBD group. We compared the short-term (≤3 years) and long-term (>3 years) recurrence of ductal stones in the two groups over a 72-month follow-up period. Potential risk factors were evaluated using a logistic regression analysis. RESULTS: A total of 291 patients completed the study. The short-term recurrence rate in the EST group was not significantly higher than that in the EST-EPBD group (P > 0.05). The long-term recurrence rate for the EST group was significantly higher than that for the EST-EPBD group (P < 0.05). The serum level of cholesterol, body mass index, gallstones, maximum stone diameter, number of stones, and mechanical lithotripsy were risk factors for the recurrence of ductal stones. Minimal size of the duodenal papilla incision was a protective factor with regard to the recurrence of ductal stones. Cholecystectomy, sex, and age were not associated with the recurrence of ductal stones. CONCLUSIONS: Small-incision EST-EPBD has a similar overall success rate and a significantly lower rate of the recurrence of ductal stones, compared with those of EST alone. Thus, the curative effect of EST-EPBD is better than that of EST alone. Minimal size of the duodenal papilla incision protects against the recurrence of ductal stones.

Effects of thyroxine and donepezil on hippocampal acetylcholine content, acetylcholinesterase activity, synaptotagmin-1 and SNAP-25 expression in hypothyroid adult rats.

A growing number of studies have revealed that neurocognitive impairment, induced by adult-onset hypothyroidism, may not be fully restored by traditional hormone substitution therapies, including thyroxine (T4). The present study has investigated the effect of T4 and donepezil (DON; an acetylcholinesterase (AChE) inhibitor) treatment on the hypothyroidism-induced alterations of acetylcholine (ACh) content and AChE activity. Furthermore, we examined synaptotagmin-1 (syt-1) and SNAP-25 expression in the hippocampus of adult rats. Adding 0.05% propylthiouracil to their drinking water for five weeks induced hypothyroidism in the rat models. From the fourth week, the rats were treated with T4, DON or a combination of both. Concentration of ACh and the activity of AChE was determined colorimetrically. The results demonstrated that hypothyroidism induced a significant decrease of Ach content and AChE activity (by 17 and 34%, respectively), which were restored to control values by T4 administration. DON treatment also restored Ach to the normal level. Protein levels of syt-1 and SNAP-25 were determined by immunohistochemistry. The results demonstrated that syt-1 was expressed at significantly lower levels in hypothyroid rats, while SNAP-25 levels were notably higher compared with the controls. Two-week treatment with T4 alone failed to normalize the expression levels of these two proteins, while co-administration of T4 and DON was able to induce this effect. These data suggested that the thyroid hormone, T4, may have a direct effect on the metabolism of hippocampal ACh in adult rats, and that the DON treatment may facilitate the recovery of synaptic protein impairments induced by hypothyroidism.

Effects of thyroxin and donepezil on hippocampal acetylcholine content and syntaxin-1 and munc-18 expression in adult rats with hypothyroidism.

Adult-onset hypothyroidism induces various impairments in hippocampus-dependent cognitive function, in which numerous synaptic proteins and neurotransmitters are involved. Donepezil (DON), an acetylcholinesterase inhibitor, has been shown to be efficient in improving cognitive function. The aim of the present study was to investigate the effects of adult-onset hypothyroidism on the expression levels of the synaptic proteins syntaxin-1 and munc-18, as well as the content of the neurotransmitter acetylcholine (ACh) in the hippocampus. In addition, the study explored the effects of thyroxin (T4) and DON treatment on the altered parameters. The study involved 55 Sprague-Dawley rats that were randomly divided into five groups: Control, hypothyroid (0.05% 6-n-propyl-2-thiouracil; added to the drinking water), hypothyroid treated with T4 (6 µg/100 g body weight once daily; intraperitoneal injection), hypothyroid treated with DON (0.005%; added to the drinking water) and hypothyroid treated with a combination of the two drugs (6 µg/100 g T4 and 0.005% DON). The concentration of ACh was determined in the homogenized hippocampus of each animal by alkaline hydroxylamine colorimetry. The protein levels of syntaxin-1 and munc-18 were determined by immunohistochemistry. The results showed that the content of ACh in the hippocampi of the hypothyroid rats was significantly decreased compared with that in the controls and that T4 monotherapy and DON administration restored the ACh content to normal values. In the hippocampi of the hypothyroid group, munc-18 was expressed at significantly lower levels, while the expression levels of syntaxin-1 were increased compared with the levels in the control group. Treatment with T4 alone restored the expression of syntaxin-1 but failed to normalize munc-18 expression levels. The co-administration of T4 and DON returned the munc-18 levels to normal values. These observations indicate that adult-onset hypothyroidism induces alterations in the levels of munc-18, syntaxin-1 and ACh in the hippocampus. Syntaxin-1 and ACh levels were restored by T4 monotherapy while munc-18 levels were not. In addition, the co-administration of T4 and DON resulted in more effective restoration than either alone. The thyroid hormone has a direct effect on metabolism of hippocampal ACh in adult rats and DON is helpful for treatment of synaptic protein impairment induced by hypothyroidism.

Investigation of a Branchlike MoO(3)/polypyrrole hybrid with enhanced electrochemical performance used as an electrode in supercapacitors.

A branchlike MoO3/polypyrrole conductive nanocomposite was facilely prepared by wrapping a homogeneous polypyrrole (PPy) layer around MoO3 nanobelts via the in situ oxidative polymerization of a self-assembled pyrrole monomer. X-ray powder diffraction characterization demonstrated that the PPy polymer does not hinder the crystallization of the MoO3 nanobelts substrate. The electrochemical tests show that the specific capacitance of 129 F g(-1) for the MoO3/PPy hybrid is higher than both pristine MoO3 and pure PPy. Moreover, the hybrid electrode with good electrical conductivity displays good cyclic stability of 90% retention after 200 cycles of charge/discharge. These results indicate a promising potential application of the MoO3/PPy nanocomposite for use as an effective electrode material in supercapacitors.

[Observation on the ultrastructure of Pneumocystis carinii].

OBJECTIVE: To study the life cycle and morphology of Pneumocystis carinii by ultrastructural observation. METHODS: Wistar rat model of P. carinii infection was established by subcutaneous injection with dexamethasone. Lung tissue of the infected rats was used for the transmission electron microscopical study. RESULTS: The organisms were mainly present in the lung alveolar cavity, and also in the alveolar septum, pulmonary macrophages and neutrophils. More trophozoites of P. carinii attached to the type I alveolar epithelial cells, and rarely to the type II alveolar epithelial cells. Most of these trophozoites showed pseudopodial evaginations on their pellicles. The nucleus-associated organelle and spindle microtubules were observed in some trophozoites. The precyst phase was in three forms: early, intermediate and late form. Synaptonemal complexes indicating meiotic nuclear divisions and a clump of mitochondria were also observed in the precyst. The pellicle of the cyst has a thickened portion with a pore. There were nucleus with nucleolus, mitochondrion, vesicles, endoplasmic reticulum and numerous ribosomes in the organisms, and tubular expansions on its surface. CONCLUSION: The life cycle of P. carinii consists of trophozoite, precyst and cyst stages. The presence of a single pore in the cyst wall reveals that pore formation may be a mode of excystation for intracystic bodies of P. carinii.

[The clinical features of acute pancreatitis in 10 cities in Shandong Province].

OBJECTIVE: To investigate and obtain a more comprehensive view of the etiology and clinical features of acute pancreatitis (AP) in Shandong Province. METHODS: 1471 cases admitted to hospital for AP were studied and collected from the ten cities of Shandong Province from January 1992 to December 2002 retrospectively. Data of each enrolled patient was recorded in a standardized form. RESULTS: In the 1471 patients, the ratio of male: female was 854:617, and also the mean age of them and the range was 43.3 and from 13 - 82 years old. 1280 had mild AP, and 191 had sever AP. Cholelithiasis (20.2%), alcohol (17.3%) and diet-induced (12.4%) were the most frequent etiologic factors, followed by biliary tract infections (5.6%), hyperlipemia (2.3%), other factors (5.1%). But in about 36.1% cases, the etiology of AP still remains unexplained. In coastal regions, cholelithiasis is the most frequent factor but in interior regions alcohol ranked first. In male, a small predominance of alcohol over cholelithiasis was seen (27.4 vs.14.3%, P < 0.01); and in female, there was a clear predominance of cholelithiasis over alcohol (28.4 vs. 3.2%, P < 0.01). The complications of AP were pancreatic pseudocyst, ascites and peritonitis, pulmonary infections, multiple organ failure, diabetes mellitus-2 and shock, etc. according to their frequencies. CONCLUSIONS: Cholelithiasis, alcohol and diet-induced factor were main etiologic factors in Shandong Province, whereas cholelithiasis alone predominated in the females. In about 36.1% cases, the etiology remains unknown. So that more attention should be paid to study the etiology of AP.