Biomedical subjects

Hong Yan

Publications and source records attributed to Hong Yan.

At least 55 records · Page 3Linked to original sources

PubMed2005

[Assessment on nutritional status among children under 3 years using anthropometry in 40 counties of western China].

OBJECTIVE: To assess nutritional status among children younger than 3 years in 40 counties of western China, using anthropometry. METHODS: With cross-sectional study and random sampling, a survey with a sample size of 7252 was conducted in 40 counties of western China on children under 3 years old. Height and weight were measured and nutrition status was evaluated with WHO/NCHS reference using Z scores. RESULTS: SD of height for age (HA) and weight for age (WA) were 1.10 - 1.30 and 1.06 - 1.40, respectively and SD of WAZ for infants varied. The distribution of HA Z and WAZ shifted downward to 1 unit and 0.4 unit for distribution of weight for height (WHZ). The prevalence of stunting, underweight and wasting were 23.0%, 22.6% and 7.5% respectively. The prevalence rates were low among those yourger than 3 months. Stunting and underweight increased sharply after 6 months and reached 20% - 30%. Significant correlation was found between underweight and stunting or wasting with coefficients of 0.815 and 0.636, respectively. No correlation was found between stunting and wasting. CONCLUSION: The nutrition status adversely affected children as a whole but not only for individuals. There was a higher prevalence of malnutrition mainly on low height to children. Weight for age must be interpreted cautiously because of the inability of this indicator in distinguishing stunting and wasting just by itself. Assessment by anthropometry called for accurate information on age and measurement of height and weight.

Anthropometry↗

PubMed2005

[Habitat characteristics for the growth of Atractylodes lancea based on GIS].

OBJECTIVE: To study the habitat characteristics for the growth of Atractylodes lancea. METHOD: The leading factors for the growth of A. lancea are determined after stepwise regression, and the limiting factor are determined by field study, literature search,and weather records. The mean values of leading factors and the limiting factors of A. lancea for 30 years were applied to do spatial interpolation using IDIRIEIW softwares. An overlay was prerformed using data obtained in Mt. Maoshan and the general habitat of A. Iancea. RESULT: It was found that precipitation is one of the dominant climate factors that affects the quality of A. lancea. High temperature was one of the limiting factor which influences the living of A. lancea. The best habitat was determined to be: annual mean temperature more than 15 degrees C, monthly mean minimum temperature between - 2- -1 degrees C, monthly mean maximum temperature about 32 degrees C, lowest tolerable temperature - 17- -15 degrees C, drought season 1 - 2 months, annual mean precipitation between 1000 - 1160 mm. CONCLUSION: Mt. Maoshan was characterized by having high temperature, short drought season and adequate precipitation. The growth of A. Lancea is a result of environmental stress.

Atractylodes↗

PubMed2005

[Clinical study on treatment of chronic hepatitis B by kurarinone combined with interferon alpha-1b].

OBJECTIVE: To study the clinical effect of combination of kurarinone (KR) and interferon a-lb (IFNalpha-1b) in treating chronic hepatitis B. METHODS: One hundred and forty-six patients with chronic hepatitis B were randomized into four groups. Under the basic conventional treatment, additional KR combined IFNa-lb was given to Group A, IFNa-lb to Group B and KR to Group C while none was given to Group D. The therapeutic course for them was 6 months and succeeded with 6 months of follow-up. Changes in liver histology, expression of transforming growth factor beta (TGF-beta) in liver tissue, and serum levels of TGF-beta, hyaluronic acid (HA), laminin (LN), collagen type IV (IVC), precollagen III (PCIII), as well as the negative conversion rate of HBeAg and HBV DNA, and normalization rate of alanine transaminase (ALT) before and after treatment were observed by immuno chemical method, RIA and ELISA. RESULTS: After treatment, in Group A, the scores of liver fibrosis and all the above-mentioned indexes significantly lowered, as compared with those in Group B and C, the difference was significant (P<0.05 or P<0.01). The negative conversion rate of TGF-beta in liver tissue was in accordance with the dynamic change of liver fibrosis. Comparison between Group B and C in those aspects showed insignificant difference (P >0.05). CONCLUSION: KR combined with IFNalpha-1b shows better effect in treating chronic hepatitis B than that of using either of the two alone.

Adult↗

PubMed2005

[Analysis and processing of two-lead ECG signals based on orthogonal synthesizing].

OBJECTIVE: To dig out the potential information in two-lead ECG signals, and discuss a new method of analyzing and processing two-lead ECG signals, viz. Orthogonal Synthesis Cardiogram (OSCG). METHOD: From a case in MIT-BIH Database, several representative heartbeats were chosen to draw a series of OSCG, and analyses were made quantitatively and qualitatively. RESULT: All species of OSCG in the case differed greatly in form. The indices picked up such as maximal vector orientation and amplitude of QRS Loop etc. could effectively distinguish all species of heartbeats. Thus gets more characteristics about the heart transformation beat by beat. CONCLUSION: OSCG is found to be a simple, capable method, suitable for use in manned space flight.

Electrocardiography↗

PubMed2005

[Influence of the enteral feeding of levorotatory arginine on severely burned patients during shock stage].

OBJECTIVE: To investigate the effects and the mechanism of action of postburn dietary supplementation of levorotatory arginine (L-Arg) on burn shock resuscitation in severely burned patients. METHODS: This study was designed to be a prospective, randomized, single blinded and controlled one. Twenty burn patients with total burn surface area (TBSA) more than 30% were enrolled and randomized into two groups; 1) Group A (n = 10): enteral feeding of 50 g/L glucose normal saline (GNS) 500 ml per day containing L-Arg (400 mg/kg.day) at equal pace with fluid infusion for shock resuscitation for 4 days. 2) Group C (n = 10): enteral feeding with only 50 g/L GNS 500 ml per day for 4 days. All of the twenty patients received equal amount of enteral feeding via an intra-gastric tube with the aid of an enteral feeding pump, started within 24 postburn hours (PBH). Venous blood was harvested from all the patients in both groups on 1, 2, 3 and 4 postburn day (PBD) for the determination of serum content of nitric oxide (NO), malondialdehyde (MDA) and the activity of serum superoxide dismutase (SOD). And the arterial content of lactate (BL) was also determined concomitantly. RESULTS: The results indicated that the serum SOD activity in group A was increased after burns, peaked on 4 PBD (68 +/- 23 U/ml), and it was obviously higher than that in group C (31 +/- 9 U/ml, P < 0.01). The serum contents of MDA and NO were decreased in both groups after burns. On 2 PBD, the serum NO level in group A decreased to the lowest level (50 +/- 14 micromol/L), which was obviously lower compared with group C (78 +/- 22 micromol/L, P < 0.01). On 4 PBD, serum MDA levels in group A (3.4 +/- 0.8 micromol/L) and group C (3.5 +/- 1.3 micromol/L) were decreased to the lowest level. The BL content in group A was obviously lower than that in group C on 2 and 3 PBD (P < 0.05 or 0.01). CONCLUSION: Enteral supplementation of L-arginine can decrease excessive NO production to a relatively normal level, and it might be beneficial to resuscitation of burn shock. It might also exert a protective effect against ischemia/reperfusion injury to burn patients.

Adolescent↗

PubMed2005

[Comparative study on the influence of arginine hydrochloride and arginine acetate on the immune function and acid-base balance in rabbits with severe burns].

OBJECTIVE: To investigate the influence of arginine hydrochloride and arginine acetate on the immune function and acid-base balance in rabbits with severe burns. METHODS: One hundred and ten flap-eared rabbits were used in the study, in which 8 served as normal control, while the rest were inflicted with 30% TBSA full thickness burn. All the rabbits were divided into 10 groups, i.e. normal control (C, n = 14), burn control (B, n = 14, with intravenous infusion of Ringer's solution), 0.3 g/kg arginine hydrochloride (AH, n = 12), 0.3 g/kg arginine acetate (AA, n = 10), 0.6 g/kg AH (n = 10), and 0.6g/kg AA (n = 10) groups, 1.2 g/kg AH (n = 10), 1.2 g/kg AA (n = 10), 2.4 g/kg AA (n = 14) and 2.4 g/kg AH (n = 12) groups. AA and AH in different doses were fed to rabbits in corresponding groups 2 times a day for 7 days. The changes in the immune function, acid-base balance, chloride ion metabolism, and mortality were determined. RESULTS: Disorder in immune system was found after severe burns, with enhanced immune function at the beginning and weakening afterwards. The lymphocytic transformation rate, the CD4/CD8 ratio, the phagocytosis rate and the chemotactic index of white blood cells on 7 post burn day (PBD) were obviously lower in B group compared with C group (P < 0.05 or 0.01). These indices were obviously higher in 1.2, 2.4 g/kg AA and AH groups than those in B group on 7 PBD (P < 0.05 or 0.01). There was no difference in improvement of immune functions between 0.3, 0.6g/kg AH, AA group and B group. The values of blood pH, base excess (BE), buffer base (BB), HCO(3)(-) level in AH group were significantly lower than those in C group on 7 PBD (P < 0.05 or 0.01), while there were no obvious changes in AA group, they were obviously higher than those in AH group (P < 0.05 or 0.01). The contents of chloride ion in but 2.4 g/kg AH group during 5 to 7 PBD were obviously higher than those in C group and 2.4 g/kg AA group (P < 0.05 or 0.01), while no difference was found between 2.4 g/kg AA and C groups. The mortality in B group was obviously higher than that in 0.3, 0.6, 1.2 g/kg AH and AA groups (P < 0.05 or 0.01), but significantly lower than that in 2.4 g/kg AA and AH groups (P < 0.05). CONCLUSION: Disorders in immune functions were observed in severely burned rabbits. Administration of arginine acetate as well as arginine hydrochloride could enhance the immune function, but arginine acetate seemed to be safer than arginine hydrochloride. Excessive dosage should be avoided to prevent a rise of the mortality.

Acetates↗

PubMed2005

[Effects of alkali-stress on Aneurolepidium chinense and Helianthus annuus].

Employing monocotyledon Aneurolepidium chinense and dicotyledon Helianthus annuus, the two species with high alkali-saline resistance as test materials, and stressing them with neutral, alkalic, and mixed salts, this paper studied the characteristics of various stresses and their interrelations, with relative growth rate (RGR) as the main strain index. The results showed that under the same concentration, alkalic salt had a stronger effect than neutral salt, and the RGR of A. chinense and H. annuus was decreased with increasing salt concentration under the same kind of salt stress and pH conditions. When the pH was higher, the RGR decreased more obviously. In addition, the proline and citric acid contents in test plants were increased with increasing stress. The transformation of proline in A. chinense was greater than that in H. annuus, while that of citric acid was in adverse. In a word, alkalic salt stress was different from neutral salt stress in stressing plants and in plant responses. Alkalic salt stress and neutral salt stress were actually two distinct kinds of stresses. The former was better called "alkali-stress", while "salt-stress" only meant neutral salt stress. The key difference between them was their different pH value. It was reasonable to consider the buffer capacity as the strength value of alkali-stress, and the salinity as the strength value of salt-stress. An interactive effect between salt-stress and alkali-stress could be seen under mixed saline and alkali stress.

Alkalies↗

PubMed2005

[Clinical study on needling method for regulating mental activities and soothing liver for treatment of melancholia].

OBJECTIVE: To observe clinical therapeutic effect of needling method for regulating mental activities and soothing liver on melancholia. METHODS: One hundred and ten cases of depression were selected according to the diagnostic criteria of depression in mood disturbance (emotional and mental disturbance) and randomly divided into a regulating mental activities and soothing liver needling group (n=50), a traditional acupuncture group (n=30) and a prozac treatment group (n=30). Their therapeutic effects were evaluated by Hamilton depression scale, Self-rating depression scale (SDS), psychiatric self-rating scale (SCL-90). RESULTS: In the regulating mental activities and soothing liver needling group, 34 cases were cured, 10 cases were markedly effective, 4 cases were effective and 1 cases were ineffective, with the cured rate of 69.4% and the total effective rate of 98.0%, which were significantly better than those in the traditional acupuncture group (the cured rate was 48.3% and the total effective rate was 89.7%), and was not significantly different with the prozac treatment group (the cured rate was 64.0% and the total effective rate was 96.0%). CONCLUSION: The needling method for regulating mental activities and soothing liver has a better therapeutic effect on depression.

Acupuncture Therapy↗

PubMed2005

[Advances in clinical and mechanism studies of acupuncture and moxibustion for treatment of depression].

OBJECTIVE: To introduce clinical and mechanism studies about treatment of depression by acupuncture and moxibustion in recent years. METHODS: Review was made from clinical controls, mechanism studies and animal experiments. CONCLUSION: Acupuncture and moxibustion have definite therapeutic effect on depression, with less adverse effects, but some problems in clinical and mechanism studies remain to be resolved.

Acupuncture↗

PubMed2005

[An experimental study on the influence of hypoxia induction factor-1alpha on the glycolysis of the rat myocardial cell under hypoxic condition].

OBJECTIVE: To investigate the influence of hypoxia induction factor-1alpha (HIF-1alpha) on glycosis of rat myocardial cell under hypoxic condition. METHODS: The myocardial cells of the rats were routinely isolated and cultured. The cells were divided into single hypoxia (H) and HIF-1alpha inhibiting (I) groups. The cells in H group were cultured in glucose-free medium with mixed low-oxygen gas [1% O2, 94% N2 and 5% CO2 (v/v)]. While the cells in I group were cultured with low-oxygen gas after the cell model of low expression of HIF-1alpha protein constructed by RNAi technique. The cells in both groups were all observed before hypoxia (routine culture) and at the time points of 1, 3, 6, 12 and 24 hours of hypoxia. The LA (lactate acid ) content in the supernatant of the culture and the activity of the key enzymes in glycolysis such as hexokinase (HK), phosphofructokinase (PFK) and lactate dehydrogenase (LDH) of both groups of cells were determined at all the time points. RESULTS: (1) After hypoxia, the HK and PFK activities of the rat myocardial cells in H and I groups were obviously increased at the beginning and decreased thereafter when compared with that before hypoxia. While the activities of HK and PFK in H group at 1, 3 and 6 hours after hypoxia were evidently higher than those in I group (P <0.05 or 0.01), and the peak activity of them in H and I groups was 159 +/- 13 U/g vs 133 +/- 55 U/g, and 298 +/- 44 U/g vs 188 +/- 55 U/g, respectively. (2) Compared with normal control (92 +/- 12 U/g), the LDH activity of the cells in H group after hypoxia increased significantly, reaching the peak at 6 hours after hypoxia (2 568 +/- 125 U/g, P < 0. 01), and it decreased thereafter, while that in I group peaked at 3 hours after hypoxia (2125 +/- 126 U/g, P <0.01). The LA content in the culture supernatant in H group increased significantly after hypoxia with the passage of time, while that in I group increased in smaller magnitude (P <0.01). CONCLUSION: High expression of HIF-1alpha in the rat myocardial cells after hypoxia could directly cause continuous enhancement of cell glycolysis, which was beneficial to the protection of myocardial cells under hypoxic condition.

Animals↗

PubMed2005

[The molecular chaperone function of alpha-crystallin in age-related cataract].

PURPOSE: To evaluate the molecular chaperone function of alpha-crystallin in age-related cataract. METHODS: alpha L-Crystallin of human clear and cataractous lenses in both the cortex and nucleus were separated by chromatography on Sephacryl S-300HR. The preventive effects of alpha L-crystallin on thermally induced aggregation of catalase were measured spectrophotometrically. The complex formation between a catalase and alpha L-crystallin during the aggregation experimental was detected by SDS-PAGE methods. RESULTS: Human alpha L-crystallin specifically prevented catalase from thermal aggregation. Its preventive ability in cortex was greatly higher than that in nucleus of clear lenses. There was a remarkably decrease of preventive ability in cataractous lenses with statistical differences between the group under 65 years old and that over 65 years old, grade II and grade IV in over 65 years group, whereas alpha L-crystallin showed no statistical change in under 65 years group but its preventive ability was diminished in grade IV. SDS-PAGE showed that the 20 kDa bands had no significant decrease in water-soluble portion after heating 0.40 mim and 2 h, whereas the 65 kD bands were increased. CONCLUSION: alpha-Crystallin can function as a molecular chaperone by preventing thermal aggregation of catalase. A decrease in chaperone function from cataractous lenses has been showed in age-dependent and opacification-dependent fashion, which may play an important role in formation of cataract.

Aged↗

PubMed2004

Carnosine protects against the inactivation of esterase induced by glycation and a steroid.

Carnosine, an endogenous histidine-containing dipeptide, protects protein from oxidation and glycation, which may contribute to a potential treatment for some conformational diseases including cataract. Glycation, the non-enzymic reaction of sugars with proteins, promotes cross-linking and further aggregation. Prolonged use of glucocorticoids is a risk factor for cataract, as is diabetes. Esterase activity in the lens is decreased in senile cataract and diabetes. Previously, we reported that glycation and a steroid inactivate esterase. Here we tested the inactivation of esterase with fructose, fructose 6-phosphate (F6P) and ribose as model glycation reactions and prednisolone-21-hemisuccinate (P-21-H) as a model steroid and investigated the ability of carnosine to protect esterase against inactivation. The activity of esterase was measured by a spectrophotometric assay using p-nitrophenyl acetate as the substrate. The modified esterase was examined electrophoretically. The esterase was progressively inactivated by F6P, fructose, ribose and P-21-H. P-21-H was more effective than the sugars. Carnosine significantly inhibited the inactivation of esterase induced by all four compounds. Carnosine decreased the extent of the cross-linking. These results provide further evidence for carnosine's role as an anti-glycation compound. It is also proposed that carnosine may be an anti-steroid agent.

Animals↗

PubMed2004

Antitumor efficacy of oblimersen Bcl-2 antisense oligonucleotide alone and in combination with vinorelbine in xenograft models of human non-small cell lung cancer.

Overexpression of Bcl-2 protein in cancer cells can inhibit programmed cell death and engender chemoresistance. Reducing Bcl-2 protein levels by using antisense oligonucleotides targeting the gene message can increase the sensitivity of cancer cells to cytotoxic agents. The objective of this work was to investigate the antitumor efficacy of the Bcl-2 antisense oligonucleotide oblimersen (Genasense; G3139), alone and in combination with vinorelbine (VNB), in an ectopic and orthotopic xenograft model of NCI-H460 human non-small-cell lung cancer. In addition to assessing therapeutic effect, Bcl-2 protein expression in tumor tissue isolated from lung and heart was measured. In the ectopic xenograft model, oblimersen at 5 and 10 mg/kg significantly inhibited tumor growth compared with saline-treated control groups, and furthermore, the antitumor effect of oblimersen was associated with down-regulation of Bcl-2 protein in isolated tumor tissue. Moreover, the combination of oblimersen with VNB was more active in inhibiting tumor growth than either drug used alone. In the orthotopic model, oblimersen treatment (5 mg/kg) increased the median survival time of mice to 33 days in comparison with a median survival time of 21 days in the control animals. With this model, the anticancer effect was demonstrated by assessing tumor growth in lung and heart tissues by hematoxylin and eosin staining and Bcl-2 expression by immunohistochemistry. When VNB at 5 mg/kg was combined with oblimersen administered at 5 mg/kg, 33% of mice survived more than 90 days. These data suggest that the combination of oblimersen and VNB may provide enhanced antitumor activities against non-small-cell lung cancer.

Animals↗

PubMed2004

Structure of the hepatocyte nuclear factor 6alpha and its interaction with DNA.

Hepatocyte nuclear factor 6 (HNF-6) belongs to the family of One Cut transcription factors (also known as OC-1) and is essential for the development of the mouse pancreas, gall bladder, and the interhepatic bile ducts. HNF-6 binds to DNA as a monomer utilizing a single cut domain and a divergent homeodomain motif located at its C terminus. Here, we have used NMR methods to determine the solution structures of the 162 amino acid residue DNA-binding domain of the HNF-6alpha protein. The resulting overall structure of HNF-6alpha has two different distinct domains: the Cut domain and the Homeodomain connected by a long flexible linker. Our NMR structure shows that the Cut domain folds into a topology homologous to the POU DNA-binding domain, even though the sequences of these two protein families do not show homology. The DNA contact sequence of the HNF-6alpha was mapped with chemical shift perturbation methods. Our data also show that a proposed CREB-binding protein histone acetyltransferase protein-recruiting sequence, LSDLL, forms a helix and is involved in the hydrophobic core of the Cut domain. The structure implies that this sequence has to undergo structural changes when it interacts with CREB-binding protein.

Acetyltransferases↗

PubMed2004

Development of an exonuclease protection mediated PCR bioassay for sensitive detection of Ah receptor agonists.

The aromatic hydrocarbon receptor (AhR) is a ligand-activated transcription factor that mediates many of the biological and toxicological effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, dioxin) and related chemicals. Here we developed a novel method to detect the presence of AhR ligands using Exonuclease Protection Mediated PCR bioassay (EPM-PCR). This assay measures the ability of a chemical to activate AhR DNA binding in vitro. In the presence of AhR ligand, an expected length PCR product was observed on electrophoresis, but no signal was detected in the absence of ligand. Real-time quantitative PCR was performed to quantify DNA bound to ligand:AhR complex. We obtained a standard curve with TCDD concentration to bound DNA copies in the range of 0.01 pM-10 nM of TCDD. Minimal detection limit of the assay was below 0.01 pM TCDD, and the whole detection time was less than 5 h. In comparison to the chemical-activated luciferase gene expression (CALUX) bioassay, EPM-PCR bioassay is more sensitive and easier to perform. These results suggest that this assay is useful for detection and quantification of TCDD and related AhR ligands in a cell-free system without the use of radioactivity.

Animals↗

PubMed2004

Treatment of HER-2/neu overexpressing breast cancer xenograft models with trastuzumab (Herceptin) and gefitinib (ZD1839): drug combination effects on tumor growth, HER-2/neu and epidermal growth factor receptor expression, and viable hypoxic cell fraction.

PURPOSE: The purpose of this research was to assess the effects of single agent and combination treatment with trastuzumab and gefitinib on tumor growth and tumor microenvironment in two HER-2/neu overexpressing breast xenograft models, MDA-MB-435/LCC6(HER-2) (LCC6(HER-2); estrogen receptor negative) and MCF-7(HER-2) (estrogen receptor positive). EXPERIMENTAL DESIGN: LCC6(HER-2) and MCF-7(HER-2) cells, both in tissue culture and xenografts grown in SCID-Rag 2M mice, were treated with trastuzumab and gefitinib, alone or in combination. The rate of tumor growth was determined. In addition, tumor HER-2/neu and epidermal growth factor receptor expression, cell viability, cell cycle distribution, and proportion of viable hypoxic cells were determined by flow cytometric analyses of single tumor cell suspensions. RESULTS: Both tumor models were very sensitive to trastuzumab and moderately sensitive to gefitinib in vivo. The combination resulted in therapeutic effects, as judged by inhibition of tumor growth, which was greater (albeit not statistically significant) than that observed with trastuzumab administered as a single agent. Trastuzumab was effective in down-regulating HER-2/neu, and gefitinib mediated a reduction in epidermal growth factor receptor expression on tumor cells. In LCC6(HER-2) tumors, trastuzumab significantly reduced tumor cell viability, which was not improved by the addition of gefitinib. Gefitinib dramatically reduced the proportion of viable hypoxic cells in LCC6(HER-2) and MCF-7(HER-2) tumors. This effect was abrogated by the addition of trastuzumab. CONCLUSIONS: Although in vivo efficacy studies in two HER-2/neu overexpressing breast xenograft models showed that the combination of trastuzumab and gefitinib was effective, analyses of various cellular parameters failed to reveal beneficial effects and argue that this drug combination may not be favorable.

Animals↗

PubMed2004

Dominant spectral component analysis for transcriptional regulations using microarray time-series data.

MOTIVATION: Microarray time-series data provides us a possible means for identification of transcriptional regulation relationships among genes. Currently, the most commonly used method in determining whether or not two genes have a potential regulatory relationship is to measure their expressional similarity using Pearson's correlation coefficient. Although this traditional correlation method has been successfully applied to find functionally correlated genes, it does have many limitations. In the hope of overcoming such circumstances and getting more insights into the transcriptional regulatory issue, we propose an autoregressive (AR)-based technique for detection of potential regulated gene pairs from time-series microarray measurements. RESULTS: We use the well-known AR modeling technique to characterize temporal gene expression data from the Spellman's alpha-synchronized yeast cell-cycle experiment. In this method, time-series expression profiles are decomposed into spectral components and correlations between profiles are then computed in a component-wise sense. We show how these component-wise correlations reveal possible regulatory relationships. Our technique is applied on known transcriptional regulations and is able to identify many of those missed by the traditional correlation method.

Algorithms↗

PubMed2004

Cluster of acute hemorrhagic appendicitis among high school students in Wuhan, China.

BACKGROUND: Features of a cluster of acute appendicitis that occurred among a high school student population in China were investigated. METHODS: Epidemiologic data, medical records, and histologic slides of resected appendices were examined. RESULTS: During a period between April 10, 1997, and June 11, 1997, 11 cases occurred in a high school, with 10 cases among 290 students enrolled at the time. From the end of the initial cluster until June, 2000, 20 additional cases were encountered. Female cases (6.5%) are more frequent than male cases (1.9%). There was a clustering pattern. Many patients had a history of mutual contact before the onset of symptoms. Pathologically, the resected appendices exhibited diffuse or focal hemorrhages in the lamina propria or within hyperplastic lymphoid follicles, and infiltration by eosinophils and by lymphocytes. Appendical tissues were examined using immunohistochemistry, but no etiologic agent was identified. CONCLUSIONS: This cluster of acute appendicitis represented a special kind of appendicitis, with features of an infectious disease in epidemiology.

Adult↗