[Non-primary solid malignancies of breast in needle core biopsy: a clinicopathological analysis of 23 cases].

Objective: To investigate the accurate diagnosis and differential diagnosis of non-primary solid malignant tumors in breast needle core biopsy. Methods: Twenty-three cases of breast, axilla or neck lymph nodes pathologically diagnosed as non-primary solid malignant tumors were collected at the First Affiliated Hospital of Nanjing Medical University, Nanjing, China from January 2013 to March 2023. The differential diagnoses and diagnostic features were analyzed, based on combining clinical data, histology, and expression characteristics of biomarkers. Results: All patients were female, with age ranging from 29 to 75 years (average 56 years). The average time from the diagnosis of primary tumor to the current diagnosis was 21 months (0 to 204 months).The primary sites included the ovary (9 cases), the lung (5 cases), the gastrointestinal tract (4 cases), the pancreas, intrahepatic bile duct, thyroid gland, nasal cavity and forearm skin (1 case each). No carcinoma in situ was found in any of the cases. The morphological differences were significant among the tumors, but similar to the primary tumors. The tumors of neuroendocrine and female reproductive tract had great morphological and immunophenotypic overlaps with breast cancer. Metastatic lung cancer cells showed obvious atypia and tumor giant cells. The morphology and immunophenotype of metastatic serous carcinoma of female reproductive system might resemble invasive micropapillary carcinoma of the breast. Metastatic adenocarcinoma of the gastrointestinal tract often had features of mucous secretion. Metastatic neuroendocrine tumors were bland in appearance and morphologically similar to solid papillary carcinoma of breast, but negative for ER. TRPS1 was mostly negative (18/23) and variably positive in ovarian (4/9) and intrahepatic bile duct (1/1) tumors. Conclusions: The diagnosis of breast needle core biopsy specimen should be combined with clinical history, imaging study, and careful examination of histological features, such as presence of in situ component, morphological similarity between the primary and metastatic tumors, and using appropriate markers to differentiate the primary from metastatic tumors.

[TRPS1 expression in salivary gland-type breast carcinoma and its clinical application].

Objective: To investigate the expression of TRPS1 in salivary gland-type breast carcinoma and its clinical application. Methods: A total of 30 cases of salivary gland-type breast carcinoma diagnosed from May 2015 to November 2022 at the Department of Pathology of the First Affiliated Hospital of Nanjing Medical University were collected. The expression of TRPS1 was detected by immunohistochemistry and compared with that of GATA3. TRPS1 and GATA3 expression in 24 cases of primary salivary gland carcinoma. Results: There were 10 cases of breast secretory carcinoma, aged 21-61 years (median 53.5 years), with the size ranging from 0.9-2.2 cm (median 1.6 cm), 2 of which were accompanied by axillary nodal macrometastasis. All patients were alive after 2-55 months of follow-up (median 29.5 months, mean 29.7 months). There were 20 cases of breast adenoid cystic carcinoma, aged 36-77 years (median 53.5 years), with the size ranging from 1.2-5.5 cm (median 2.5 cm), 3 of which were accompanied by axillary nodal macrometastasis. All patients were alive after 3-92 months of follow-up (median 22.5 months, mean 31.7 months), and 1 patient had lung metastasis 15 months after surgery. The medium/high expression ratio of TRPS1 in breast secretory carcinoma was 10/10, which was higher than that of GATA3 (7/10). TRPS1 was also positive in the 2 cases with lymph node metastases. The medium/high expression rate of TRPS1 in breast adenoid cystic carcinoma was 20/20, which was significantly higher than that of GATA3 (2/20). TRPS1 was highly expressed in both classic and solid subtypes, while GATA3 was only expressed in a few cases of the classic subtype. TRPS1 was also positive in 3 cases with lymph node metastases and 1 case of the pulmonary metastases. The expression level of TRPS1 was the same in 1 case before and after neoadjuvant chemotherapy. In addition, TRPS1 was positive in parotid secretory carcinoma and adenoid cystic carcinoma. The medium/high expression rate of TRPS1 in parotid secretory carcinoma (6/6) was higher than that of GATA3 (2/6), and the medium/high expression rate of TRPS1 in parotid adenoid cystic carcinoma (17/18) was higher than that of GATA3 (2/18). Conclusions: The expression of TRPS1 is highly sensitive to salivary gland-type breast carcinoma, especially in GATA3-negative solid subtype of adenoid cystic carcinoma, which plays an important role in clinical practice.

[Efficacy comparison between a new generation of artificial ligaments and bone-patellar tendon-bone autograft for anterior cruciate ligament revision].

Objective: To compare the clinical efficacy of a new generation of ligaments (LARS artificial ligament) and bone-patellar tendon-bone (BPTB) autograft as grafts in anterior cruciate ligament (ACL) revision. Methods: A retrospective cohort study. The clinical data of 54 patients who underwent ACL revision from January 2018 to June 2020 in the First Hospital Affiliated to Army Medical University were retrospectively analyzed. There were 44 males and 10 females with a mean age of (28.5±7.7) years (15-45 years). Among them, 24 cases underwent ACL revision with LARS artificial ligament (LARS group), the other 30 cases underwent ACL revision with BPTB (BPTB group). The subjective and objective knee joint evaluation indexes were compared between the two groups to evaluate the clinical efficacy. The subjective evaluation indexes included Tegner score, Lysholm score and the International Knee Documentation Committee (IKDC) score. The objective evaluation indexes included the Lachman test, pivot-shift test, the anterior tibial translation (ATT) measurement at the weight-bearing position and the rate of patients returned to pre-injury sports. Results: The follow-up period was (32.8±5.3) months (24-42 months). At the last follow-up, the IKDC score, Tegner score and Lysholm score in the two groups significantly increased when compared with those before surgery (all P<0.05), and there was no significant difference in those indexes between the two groups (all P>0.05). The ATT measurement in the weight-bearing position was (3.1±0.7) mm in the LARS group and it was (4.1±0.9) mm in the BPTB group, which were significantly improved when compared with those before surgery (both P<0.05), and it was better in the LARS group than in the BPTB group (P<0.05). Postoperative Lachman test and pivot-shift test results in the LARS group were better than those in the BPTB group with statistically significant difference (both P<0.05). The rate of patients returned to pre-injury sports one year after surgery was 79.2%(19/24) in the LARS group and it was 50.0%(15/30) in the BPTB group, and the difference was statistically significant (P=0.029). Conclusions: Both LARS artificial ligament and BPTB autograft can achieve good short-term clinical efficacy in ACL revision, but LARS artificial ligament group has more advantages than BPTB autograft group in knee stability and early return to sports.

[Comparative analysis of metagenomic and 16S rDNA sequencing in gut microbiota of healthy elderly].

Objective: To explore the differences in subsequent analysis between metagenomic and 16Sr DNA sequencing in compositionally characterizing gut microbiota of healthy elderly. Methods: By using a panel study design, five monthly repeated measurements were performed among 76 healthy older people in Jinan City, Shandong Province. Their fecal samples were collected, and genomic DNA was extracted and analyzed through metagenomic and 16Sr DNA sequencing to compare the composition and diversity of gut microbiota. The correlation between species abundance and α diversity was analyzed by Pearson correlation analysis, and the correlation between species abundance and ß diversity was determined by Procrustes analysis. Results: The age of 76 participants was (65.07±2.75), and the body mass index was (25.03±2.40) kg/m2. There were 38 males and 38 females. A total of 345 fecal samples were obtained from five monthly repeated measurements. Compared with 16S rDNA sequencing, metagenomic sequencing showed more annotated species at each level. The difference in the number of two sequencing species increased with the decrease of the level. Although there were significant differences in species richness between the two sequencing methods. Their species richness was highly correlated at both phylum (r=0.88, P<0.001) and genus (r=0.77, P<0.001) levels. Bacteroidetes and Firmicutes were the common dominant species. Gut microbiota diversity analysis further showed that there was a significantly positive correlation between α diversity (r=0.70, P<0.001) and ß diversities (M2=0.84, P<0.05) in the two groups. Conclusion: The annotation efficiency of metagenomic sequencing is much higher than that of 16S rDNA sequencing. The two sequencing methods are consistent in phylum abundance as well as α diversity.

The role and contribution of magnetic fields, characterized via their magnetic flux, to the statistical structuring of the solar atmosphere.

The anomalous heating of the solar upper atmosphere is one of the eight key problems in modern astronomy. Moreover, the stratification of the solar atmosphere is an outstanding key-problem in solar physics. In this study, a hot butterfly-like pattern is found to run through the chromosphere to the corona lying right on top of the magnetic butterfly pattern of sunspots in the photosphere. We thus propose to introduce the term butterfly body to describe the butterfly diagram in the 3-dimensional atmosphere. Besides, we discuss the so-called polar brightening in different layers. It is found to be statistically in anti-phase with the solar cycle in the photosphere and the chromosphere, while in phase with the solar cycle in the corona. Accordingly, we describe the role and relationship of solar magnetic elements of different magnetic flux strengths to explain the statistical structuring of the solar atmosphere with the butterfly body over the solar cycle.

Infection control measures for public transportation derived from the flow dynamics of obstructed cough jet.

During the COVID-19 pandemic, WHO and CDC suggest people stay 1 m and 1.8 m away from others, respectively. Keeping social distance can avoid close contact and mitigate infection spread. Many researchers suspect that suggested distances are not enough because aerosols can spread up to 7-8 m away. Despite the debate on social distance, these social distances rely on unobstructed respiratory activities such as coughing and sneezing. Differently, in this work, we focused on the most common but less studied aerosol spread from an obstructed cough. The flow dynamics of a cough jet blocked by the backrest and gasper jet in a cabin environment was characterized by the particle image velocimetry (PIV) technique. It was proved that the backrest and the gasper jet can prevent the front passenger from droplet spray in public transportation where maintaining social distance was difficult. A model was developed to describe the cough jet trajectory due to the gasper jet, which matched well with PIV results. It was found that buoyancy and inside droplets almost do not affect the short-range cough jet trajectory. Infection control measures were suggested for public transportation, including using backrest/gasper jet, installing localized exhaust, and surface cleaning of the backrest.

Airborne infection risk of nearby passengers in a cabin environment and implications for infection control.

BACKGROUND: Expiratory droplets cause high infection risk to nearby passengers via airborne route. METHODS: We built a two-row four-seat setup to simulate a public transport cabin. A cough generator and a nebulizer were used to simulate the cough and talk processes respectively. Exposure and infection risk of nearby passengers was studied. The effect of gasper jet and backrest on risk mitigation was investigated. RESULTS: For the activity of coughing, the front passenger has much higher infection risk, which was around four times of that of other passengers, because of the concentration surge in the inhalation zone. For talking, the nearby passengers have similar infection risk because nearby passengers were all exposed to concentration surges with similar peak value. Gasper jet of the infected passenger and higher backrest can extinguish or reduce the concentration surge of front passengers and reduce the infection risk due to coughing and talking droplets. CONCLUSION: The passengers near the infected passenger have very high infection risk. The overhead gasper and a higher backrest can reduce the exposure and mitigate the risk of infection. It is believed that the control measures to protect nearby passengers are urgently needed in public transport cabins.

Synergistic effects ofα-Fe2O3nanoparticles and Fe-doping on gas-sensing performance of NiO nanowires and interface mechanism.

High surface area nickel oxide nanowires (NiO NWs), Fe-doped NiO NWs andα-Fe2O3/Fe-doped NiO NWs were synthesized with nanocasting pathway, and then the morphology, microstructure and components of all samples were characterized with XRD, TEM, EDS, UV-vis spectra and nitrogen adsorption-desorption isotherms. Owing to the uniform mesoporous template, all samples with the same diameter exhibit the similar mesoporous-structures. The loadedα-Fe2O3nanoparticles should exist in mesoporous channels between Fe-doped NiO NWs to form heterogeneous contact at the interface of n-typeα-Fe2O3nanoparticles and p-type NiO NWs. The gas-sensing results indicate that Fe-dopant andα-Fe2O3-loading both improve the gas-sensing performance of NiO NWs sensors.α-Fe2O3/Fe-doped NiO NWs sensors presented the highest response to 100 ppm ethanol gas (55.264) compared with Fe-doped NiO NWs (24.617) and NiO NWs sensors (3.189). The donor Fe-dopant increases the ground state resistance and the absorbed oxygen content in air.α-Fe2O3nanoparticles in electron depletion region result in the increasing resistance in ethanol gas and decreasing resistance in air. In this way,α-Fe2O3/Fe-doped NiO NWs sensor presents the excellent gas-sensing performance due to the formation of heterogeneous contact at the interface.

First Evidence of Local E×B Drift in the Divertor Influencing the Structure and Stability of Confined Plasma near the Edge of Fusion Devices.

The structure of the edge plasma in a magnetic confinement system has a strong impact on the overall plasma performance. We uncover for the first time a magnetic-field-direction dependent density shelf, i.e., local flattening of the density radial profile near the magnetic separatrix, in high confinement plasmas with low edge collisionality in the DIII-D tokamak. The density shelf is correlated with a doubly peaked density profile near the divertor target plate, which tends to occur for operation with the ion B×∇B drift direction away from the X-point, as currently employed for DIII-D advanced tokamak scenarios. This double-peaked divertor plasma profile is connected via the E×B drifts, arising from a strong radial electric field induced by the radial electron temperature gradient near the divertor target. The drifts lead to the reversal of the poloidal flow above the divertor target, resulting in the formation of the density shelf. The edge density shelf can be further enhanced at higher heating power, preventing large, periodic bursts of the plasma, i.e., edge-localized modes, in the edge region, consistent with ideal magnetohydrodynamics calculations.

[Establishing reference intervals of thyroid hormone based on a laboratory information system].

Objective: To establish reference intervals (RIs) of thyroid hormone based on data from healthy subjects in laboratory information system (LIS) by indirect methods. Methods: Data were selected from the physical examination center in LIS of the First Hospital of Jilin University from May 2014 to December 2018. The normal distribution of the original data was checked by the Kolmogorov-Smirnov test. Skewed data were transformed into normal distribution using BOX-COX techniques, and outliers were identified by the Turkey method. The continuous percentile curve was established by coefficient of skewness-median-coefficient of variation(LMS) methods. Cut-off value of age was determined by decision trees, and the differences between groups were verified by Z-tests. P(2.5) and P(97.5) in the RIs were analyzed by non-parametric methods. Results: A total of 45 742 subjects were included in the study. There were no differences in the RI for thyroid stimulating hormone (TSH) among age groups or between men and women (Z

Rubber seed oil and flaxseed oil supplementation alter digestion, ruminal fermentation and rumen fatty acid profile of dairy cows.

Rubber seed oil (RO) that is rich in polyunsaturated fatty acids (FA) can improve milk production and milk FA profiles of dairy cows; however, the responses of digestion and ruminal fermentation to RO supplementation in vivo are still unknown. This experiment was conducted to investigate the effect of RO and flaxseed oil (FO) supplementation on nutrients digestibility, rumen fermentation parameters and rumen FA profile of dairy cows. Forty-eight mid-lactation Holstein dairy cows were randomly assigned to one of four treatments for 8 weeks, including basal diet (CON) or the basal dietary supplemented with 4% RO, 4% FO or 2% RO plus 2% FO on a DM basis. Compared with CON, dietary oil supplementation improved the total tract apparent digestibility of DM, neutral detergent fibre and ether extracts ( P < 0.05). Oil treatment groups had no effects on ruminal digesta pH value, ammonia N and microbial crude protein ( P > 0.05), whereas oil groups significantly changed the volatile fatty acid (VFA) profile by increasing the proportion of propionate whilst decreasing total VFA concentration, the proportion of acetate and the ratio of acetate to propionate ( P < 0.05). However, there were no differences in VFA proportions between the three oil groups (P > 0.05). In addition, dietary oil supplementation increased the total unsaturated FA proportion in the rumen by enhancing the proportion of trans-11 C18:1 vaccenic acid (VA), cis-9, trans-11 conjugated linoleic acid (CLA) and α-linolenic acid (ALA) ( P < 0.05). These results indicate that dietary supplementation with RO and FO could improve nutrients digestibility, ruminal fermentation and ruminal FA profile by enhancing the VA, cis-9, trans-11 CLA and ALA composition of lactating dairy cows. These findings provide a theoretical basis for the application of RO in livestock production.

[Ramsey-Hunt syndrome with initial syndrome of hoarseness: a case report].

Summary Ramsey-Hunt syndrome is caused by the varicella zoster virus, which mainly affects the facial nerve. The typical clinical features of Ramsey-Hunt syndrome are peripheral facial paralysis and ear herpes. In this case, initial symptoms were hoarseness and coughing, afterwards typical symptom occurred 5 days later which were earache, late-onset herpes, and facial paralysis. Ramsey-Hunt syndrome are difficult to diagnose because of its seemingly unrelated initial symptoms.

Effects of source on bioavailability of selenium, antioxidant status, and performance in lactating dairy cows during oxidative stress-inducing conditions.

In the current study, we used heat stress (HS) as an oxidative stress model to examine the effects of hydroxy-selenomethionine (HMSeBA), an organic selenium source, on selenium's bioavailability, antioxidant status, and performance when fed to dairy cows. Eight mid-lactation Holstein dairy cows (141 ± 27 d in milk, 35.3 ± 2.8 kg of milk/d, parity 2 or 3) were individually housed in environmental chambers and randomly assigned to 1 of 2 treatments: inorganic Se supplementation (sodium selenite; SS; 0.3 mg of Se/kg of dry matter; n = 4) or HMSeBA supplementation (0.3 mg of Se/kg of dry matter; n = 4). The trial was divided into 3 continuous periods: a covariate period (9 d), a thermal neutral (TN) period (28 d), and a HS period (9 d). During the covariate and TN periods, all cows were housed in TN conditions (20°C, 55% humidity). During HS, all cows were exposed to cyclical HS conditions (32-36°C, 40% humidity). All cows were fed SS during the covariate period, and dietary treatments were implemented during the TN and HS periods. During HS, cows fed HMSeBA had increased Se concentrations in serum and milk, and total Se milk-to-serum concentration ratio compared with SS controls. Superoxide dismutase activity did not differ between Se sources, but we noted a treatment by day interaction in glutathione peroxidase activity as HS progressively reduced it in SS controls, whereas it was maintained in HMSeBA cows. Supplementation with HMSeBA increased total antioxidant capacity and decreased malondialdehyde, hydrogen peroxide, and nitric oxide serum concentrations compared with SS-fed controls. We found no treatment effects on rectal temperature, respiratory rate, or dry matter intake. Supplementing HMSeBA tended to increase milk yield and decrease milk fat percentage. No other milk composition parameters differed between treatments. We observed no treatment effects detected on blood biochemistry, except for a lower alanine aminotransferase activity in HMSeBA-fed cows. These results demonstrate that HMSeBA supplementation decreases some parameters of HS-induced oxidative stress.

Design of Langmuir probe diagnostic system for the upgraded lower tungsten divertor in EAST tokamak.

In order to achieve long-pulse H-mode plasma scenario over 400 s with high heating power in the Experimental Advanced Superconducting Tokamak (EAST) device, the lower graphite divertor will be upgraded into a tungsten (W) divertor with active water cooling, which consists of the W/Cu monoblock units and the W flat-tile units as the divertor plasma facing components. As a fundamental diagnostic tool, the divertor Langmuir probe (Div-LP) diagnostic system will be upgraded accordingly. This paper presents the design of two kinds of new Div-LP systems, which are planned to be utilized on the W/Cu monoblock units and the W flat-tile units for the upgraded lower tungsten divertor, respectively, including their structures and preliminary poloidal and toroidal layouts. The Div-LP diagnostic system can measure the plasma parameters with the schemes of triple-probe, double-probe, and single-probe, to obtain the spatial and temporal distribution of plasma behavior on the divertor targets, which is useful for the discharge control and operation in EAST. In addition, the thermal analysis of the two kinds of probe assemblies is also carried out by using the three-dimensional finite element code ANSYS, which is aimed to get the optimal designs to withstand the long-pulse and high-power operation in EAST future experiments.

Survey on Physical Fitness and Cardiovascular Function of the City Elderly in Different Regular Physical Activities in China.

OBJECTIVE: To explore the relationship between sports law project selection and physical health, cardiovascular function of the city elderly. DESIGN AND SETTING: To investigate the state of regular physical activity, physical health, and cardiovascular function. PARTICIPANTS: 1,555 city elderly people aged 60-69 years in 10 cities of Shaanxi Province. MEASUREMENTS: Clinical and anthropometrics measurements included height, weight, waistline, blood pressure, heart rate, strength, balance, flexibility. RESULTS: The sports participation rate for the samples was 51.38%, which was with fitness walking (61.08%), Tai Chi (12.52%), fitness run (11.51%), dance(8.89%)as the main items; There were statistically significant difference in WHtR (F = 2.63), heart rate (F = 3.43), balance (F = 4.51), flexibility (F = 3.57), strength (F = 24.69) (all P < 0.05) for the two groups of elderly; Compared with the non-regular physical activity groups, these groups of fitness walking, Tai Chi and fitness running were statistically significant (all P<0.05). The systolic blood pressure (t = 4.18), diastolic blood pressure (t = 2.02), heart rate (t= -2.13), balance (t= 2.88) of fitness walking group were improved markedly. The balance (t = 4.42, P = .000) of Tai Chi group was significant. The strength (t = 2.48, P = .013) of fitness running group was significant. CONCLUSION: The project of regular physical activity can effectively improve the physical health level and heart vascular function of the elderly people. WHtR was suitable for evaluating physical fitness of elderly people in regular sports. Fitness walking, Tai Chi, fitness running can effectively improve the obese elderly obesity levels and reduce the risk of cardiovascular disease. Fitness walking program can improve heart rate and blood pressure levels, and it also can be recommended as an exercise for improving the level of cardiovascular function, with the flexibility exercise being added. Tai Chi helped the elderly to improve their balance level and prevent falls. Fitness running helped to improve the elderly power and slow down the process of muscle degradation. The choice of Regular sports activities for the elderly was single, not according to their own physical or chronic disease of the targeted exercise.

Two unilateral puncturation comparative analyses of multiple-level fresh osteoporotic vertebral body compression fractures treated with percutaneous vertebroplasty guided by C-arm fluoroscopy or in senile patients.

OBJECTIVE: To compare the curative effects of two unilateral puncturation percutaneous vertebroplasty (PVP) for the pain caused by multiple-level osteoporotic vertebral body compression fractures (OVCF) in senile patients. PATIENTS AND METHODS: From June 2008 to November 2014, eighty-nine cases suffering from fresh multiple-level OVCF were randomly divided into experimental group (n=51) and control group (n=38). Patients underwent PVP guided by C-arm fluoroscopy in the prone position. We monitored and recorded the visual analgesic scale (VAS) at pre-operation and 2 days post-operation, operation time, exposure duration, bone cement injection amount and extraosseous cement leakages. RESULTS: PVP procedures were successful in both groups without serious complications. The VAS scores in both two groups at 2 days post-operation were significantly lower than VAS scores at pre-operation (p<0.05). The operation time and exposure duration in the observational group were significantly lower than those in the control group (p<0.05). However, bone cement injection amount and extraosseous cement leakages in the observing group were similar to those in control (p>0.05). CONCLUSIONS: The curative effects of two unilateral puncturation PVPs were satisfactory. However, puncturation method had lower operation time and lower X-ray exposure dose. We concluded that puncturation method was a suitable method to be considered for clinical application.

Effects of dietary neutral detergent fiber and starch ratio on rumen epithelial cell morphological structure and gene expression in dairy cows.

This study was designed to investigate the effect of dietary neutral detergent fiber to starch ratio on rumen epithelial morphological structure and gene expression. Eight primiparous dairy cows including 4 ruminally fistulated cows were assigned to 4 total mixed rations with neutral detergent fiber to starch ratios of 0.86, 1.18, 1.63, and 2.34 in a replicated 4 × 4 Latin square design. The duration of each period was 21 d including 14 d for adaptation and 7 d for sampling. Rumen epithelial papillae were collected from the ruminally fistulated cows for morphological structure examination and mRNA expression analysis using quantitative real-time PCR of several genes related to volatile fatty acid absorption and metabolism, and cellular growth. Increasing dietary neutral detergent fiber to starch ratio resulted in a linear increase in the thickness of the stratum spinosum and basale. In contrast, expression of HMGCS2 (encoding the rate-limiting enzyme in the synthesis of ketone bodies) decreased linearly, whereas the expression of MCT2 (encoding a transporter of volatile fatty acid) increased linearly with increasing dietary neutral detergent fiber to starch ratio. As dietary neutral detergent fiber to starch ratio increased, expression of IGFBP5 (a gene related to the growth of rumen epithelial papillae) decreased, whereas IGFBP6 expression increased. Both of these IGFBP genes are regulated by short-chain fatty acids. Overall, the data indicate that dietary neutral detergent fiber to starch ratio can alter the thickness of the rumen epithelial papillae partly through changes in expression of genes associated with regulating volatile fatty acid absorption, metabolism, and cell growth.

Establishment of heterotopic ossification via sharp instrument injury in rats.

OBJECTIVE: To establish an animal model for heterotopic ossification (HO) induced by sharp instrument injury in Sprague-Dawley (SD) rat and to investigate its possible mechanism. MATERIALS AND METHODS: A total of 48 male SD rats were divided into 3 groups (n=16). In sham group, incision and suture were performed only in the left leg. Partial tenotomy was performed in the left Achilles tendons in the PAT group. In Achilles' tenotomy (AT) group, tenotomy was performed in the left Achilles tendons to establish animal model of EO. X-ray and histological examinations were made at 6 and 10 weeks after operation. RESULTS: No HO occurred in the sham and PAT groups. In AT group, X-ray results on 4 rats showed cartilage and bone formation while the remaining 4 rats showed chondrification in histological examination at 6 weeks after operation. At 10 weeks all rats showed bone formation with trabecular bone. This kind of HO usually develops through a process of endochondral ossification. CONCLUSION: Tenotomy is a simple, effective and feasible method to induce HO.