Value of pseudopod sign on high-frequency ultrasound in predicting the pathological invasion of extramammary Paget's disease lesions

BACKGROUND

Vertical invasion of extramammary Paget's disease (EMPD) is associated with poor prognosis. The usual vertical invasion route is directly downward or along the skin appendages. High-frequency ultrasound (HFUS) can be used to measure the EMPD lesion thickness, and visualize the pseudopod extensions due to skin appendage involvement. It is a non-invasive method for evaluating the extent of vertical invasion in EMPD.

OBJECTIVE

To investigate the value of HFUS in predicting the extent of vertical invasion in EMPD.

METHODS

In this retrospective study, 85 patients with EMPD were divided into two groups based on the pathology: invasive EMPD (iEMPD) group (n = 13) and in situ EMPD group (n = 72). The clinical and HFUS features of both the groups were analyzed. The different types of pseudopodia morphology on HFUS were as follows: no pseudopodia, irregular bottom, small sphere, short strip, long strip, vase shape, and nodular convex. These were further stratified into low-risk and high-risk levels.

RESULTS

The clinical features were comparable between the two groups (P > .05). There were significant differences between the two groups in the HFUS features (lesion thickness, lesion shape, bottom shape, layer involvement, pseudopodia morphology, and color Doppler blood flow signal; all P < .05). The distribution of the pseudopodia morphology types in the in situ EMPD and iEMPD groups, was as follows: no pseudopodia, 30/72 and 0/13; irregular bottom, 5/72 and 0/13; small sphere, 5/72 and 0/13; short strip, 21/72 and 0/13; long strip, 8/72 and 3/13; vase shape, 3/72 and 3/13; and nodular convex, 0/72 and 7/13 (P < .05 for all). The sensitivity and specificity of high-risk pseudopodia in identifying iEMPD were 100% and 84.7%, respectively.

CONCLUSIONS

HFUS provides morphological information regarding EMPD lesions. Risk stratification for pseudopodia can help to distinguish between iEMPD and in situ EMPD lesions.

The new-generation proteasome inhibitor oprozomib increases the sensitivity of cervical cancer cells to cisplatin-induced apoptosis

This study aimed to evaluate the anti-tumor effect of a new generation of protease inhibitor, oprozomib (OPZ), used alone and in combination with cisplatin, also called CDDP, on cervical cancer. Five different types of cervical cancer cell lines - HeLa, Caski, HeLa-CDDP, C33a, and SiHa - and one nontransformed cervical cell line - HaCaT -were treated with OPZ alone or in combination with cisplatin. The inhibitory effects of OPZ and cisplatin on the proliferation of cervical cancer cells were then analyzed using cytotoxicity tests, flow cytometry, and Western blotting. It was found that OPZ alone or in combination with cisplatin can reduce the proliferation of the five types of cancer cells by enhancing the lysis of caspase-3 and PARP and inducing cancer cell apoptosis. In the combined treatment, OPZ was found to inhibit the degradation of inhibitory factor κB alpha induced by cisplatin, thereby inhibiting the activation of NF-κB, which causes cisplatin resistance, and enhancing the sensitivity of the tumor cells to cisplatin. Moreover, OPZ promoted the phosphorylation of the apoptosis signaling pathway JNK that was activated by cisplatin, thereby inducing tumor cell apoptosis. These findings provide a theoretical basis for the clinical use of OPZ alone and in combination with cisplatin in the treatment of cervical cancer.

[Efficacy and safety of segmental radiofrequency ablation for isolation of the superior vena cava in patients with atrial fibrillation]

Objective: To analyze the three-dimensional distribution of functional sinus node, right phrenic nerve and superior vena cava(SVC)-right atrial muscle sleeves by three-dimensional electrophysiological technique in patients with atrial fibrillation (AF), and to investigate the efficacy and safety of segmental radiofrequency catheter ablation (RFCA) for isolation of superior vena cava in these patients. Methods: In this retrospective study, we enrolled 136 AF patients who underwent first RFCA in the First Affiliated Hospital of Zhengzhou University from July 2018 to June 2019 and all patients underwent SVC isolation under sinus rhythm. Baseline clinical data of patients were collected. The functional sinus node was defined by activation mapping, pacing was guided by three-dimensional mapping (Carto) system, localization of the right phrenic nerve was defined by pacing map, the superior vena cava-right atrial muscle sleeves was determined according to the change of potential during SVC isolation, segmental RFCA was performed for SVC isolation, the three-dimensional distribution of functional sinus node, right phrenic nerve and superior vena cava(SVC)-right atrial muscle sleeves was determined by three-dimensional electrophysiological technique. Immediate SVC isolation was achieved in all patients. Patients were evaluated immediately after RFCA and patients were followed at 3, 6, 9, and 12 months after RFCA. Holter monitoring was performed every 3 months, the chest radiograph and the SVC ultrasonic examination were performed every 6 months after RFCA. Postoperative complications were assessed. Results: The mean age of the 136 patients with AF was (51.6±14.2) years, 86 (63.2%) were male, 98 cases (72.1%) were paroxysmal AF and 38 cases (27.9%) were persistent AF. Right atrium activation mapping revealed that 17 (12.5%) functional sinus node were located in the SVC, 78 (57.4%) were located at the SVC-right atrium junctions, 41 (30.1%) were located below the junction level. From the head to foot view, 83 (61.0%) functional sinus node were located at the anterior lateral segment of the SVC-right atrium three-dimensional reconstruction model, 34 (25.0%) located at the posterior lateral segment, 15 (11.0%) located at the anterior wall, 4 (2.9%) located at posterior wall or anterior septum. A total of 294 SVC muscle sleeves were detected among all patients, 94 (32.0%) SVC muscle sleeves were located at the anterior septum of the SVC-right atrium three-dimensional reconstruction model, 76 (25.9%) were located at the posterior septum, 21(7.1%) were located at the posterior free wall, 11 (3.7%) were located at the posterior lateral, 27 (9.2%) were located at anterior lateral wall and 65 (22.1%) were located at the anterior free wall. Right phrenic nerve positioned relatively fix, 133 (97.8%) were located at the lateral segment of the SVC-right atrium three-dimensional reconstruction model, 3 (2.2%) were located at the anterior free wall. Sinus rhythm and SVC isolation were successfully restored immediately after RFCA, no significant SVC stenosis, right phrenic nerve palsy and functional sinus node injury occurred immediately post procedure. All patients were followed up for (11.2±3.6) months and none had postoperative complication. Conclusions: Three-dimensional electrophysiological can determine the spatial location of functional sinus node, right phrenic nerve and SVC-right atrial sleeves. On this basis, segmental RFCA is a safe and effective method to achieve complete isolation of SVC.

Association of body mass index with immune recovery, virological failure and cardiovascular disease risk among people living with HIV

OBJECTIVES

We conducted a longitudinal cohort analysis to evaluate the association of pre-treatment body mass index (BMI) with CD4 recovery, virological failure (VF) and cardiovascular risk disease (CVD) markers among people living with HIV (PLHIV).

METHODS

Participants who were enrolled between January 2003 and March 2019 in a regional Asia HIV cohort with weight and height measurements prior to antiretroviral therapy (ART) initiation were included. Factors associated with mean CD4 increase were analysed using repeated-measures linear regression. Time to first VF after 6 months on ART and time to first development of CVD risk markers were analysed using Cox regression models. Sensitivity analyses were done adjusting for Asian BMI thresholds.

RESULTS

Of 4993 PLHIV (66% male), 62% had pre-treatment BMI in the normal range (18.5-25.0 kg/m² ), while 26%, 10% and 2% were underweight (< 18.5 kg/m² ), overweight (25-30 kg/m2) and obese (> 30 kg/m² ), respectively. Both higher baseline and time-updated BMI were associated with larger CD4 gains compared with normal BMI. After adjusting for Asian BMI thresholds, higher baseline BMIs of 23-27.5 and > 27.5 kg/m² were associated with larger CD4 increases of 15.6 cells/µL [95% confidence interval (CI): 2.9-28.3] and 28.8 cells/µL (95% CI: 6.6-50.9), respectively, compared with normal BMI (18.5-23 kg/m² ). PLHIV with BMIs of 25-30 and > 30 kg/m² were 1.27 times (95% CI: 1.10-1.47) and 1.61 times (95% CI: 1.13-2.24) more likely to develop CVD risk factors. No relationship between pre-treatment BMI and VF was observed.

CONCLUSIONS

High pre-treatment BMI was associated with better immune reconstitution and CVD risk factor development in an Asian PLHIV cohort.

[Electrophysiological characteristics and therapeutic efficacy of radiofrequency ablation of focal atrial tachycardia originating from the right atrial appendage during pregnancy]

Objective: To analyze the electrophysiological characteristics and the therapeutic efficacy of irrigated-tip catheter radiofrequency ablation(RFA) without radiation for pregnant women with focal atrial tachycardia(AT) originating from the right atrial appendage (RAA). Methods: Data from 55 women with focal AT, who underwent radiofrequency ablation (RFA) in the First Affiliated Hospital of Zhengzhou University from October 2016 to March 2019, were screened. 2 non-pregnant women with right atrial appendage tachycardia (RAAT) and 4 pregnant women with non-RAAT were excluded. The remaining 49 cases were divided into RAAT during pregnancy group (n=6, including 4 cases of tachycardia-induced cardiomyopathy) and non-pregnant and non-RAAT group (control, n=43). Under the guidance of three-dimensional mapping system, the earliest activation site was identified, RFA with the irrigated catheter without x-ray fluoroscopy was performed in RAAT patients during pregnancy, all patients in control group underwent non-zero-ray ablation. Patients were followed up at 3, 6, 12 months post procedure, and yearly follow up thereafter in outpatient clinic. Electrocardiogram or Holter monitoring was performed during follow up. AT recurrence and surgical complications were recorded during follow up. At 6 months after RFA, echocardiography examination and laboratory examination including N-terminal B-type brain natriuretic peptide measurement were performed in the pregnant patients, delivery results were also recorded in the pregnant patients. The electrophysiological characteristics of RAAT during pregnancy were analyzed, the therapeutic efficacy of RFA was compared between the two groups. Results: This study is a retrospective study. Age ((30.7±6.2)years vs. (57.2±11.7)years), left ventricular ejection fraction ((46.0±12.8)% vs. (60.1±5.9)%), proportions of organic heart disease (0% vs. 58%) were significantly lower in the RAAT patients during pregnancy group than in control group (P<0.05), while proportions of patients with persistent tachycardia (100% vs. 7%), symptoms of chest distress and palpitation (6/6 vs. 49%) and left ventricular ejection farction≤50% (4/6 vs. 9%) were significantly higher in RAAT group than in control group (P<0.05), heart rate was similar between the two groups ((163.7±11.1)beats/minutes vs. (153.7±15.2)beats/minutes, P>0.05). The characteristic P-wave morphology was observed in RAAT patients during pregnancy, i.e, P wave was mostly upright (5/6) in inferior-leads (Ⅱ, Ⅲ, aVF) and in lead I and aVL, deep and wide negative P wave was found in V₁ lead (5/6), and gradually became positive from V₂-V₆. The mean tachycardia cycle length was (361.7±38.5) ms. Three-dimensional mapping showed that the origin points of the 6 RAAT pregnant patients were all scattered in the local region, the local region was ablated accordingly, 2 patients (2/6) received extensive ablation of local areas. Immediate successful rate was similar between the two groups (6/6 vs. 93%). During follow up ((15.3±4.0) months), no complications were observed after RFA, postoperative recurrence rate was similar (1/6 vs. 12%). Uncomplicated delivery was reported in all 6 pregnant RAAT post ablation. Normal cardiac structure and function was observed in the 4 pregnant patients with tachycardia-induced cardiomyopathy post ablation. Compared to pre-ablation phase, reduced left atrial dimension ((30.3±1.3) mm vs. (36.8±6.7) mm, P>0.05), increased left ventricular ejection fraction ((64.0±2.9)% vs. (39.8±10.7)%), reduced left ventricular end-diastolic dimension ((44.8±4.0) mm vs. (60.0±2.9) mm) and reduced N-terminal B-type natriuretic peptide value ((136.2±47.5) ng/L vs. (3 408.4±901.3) ng/L) were observed at 6 months post ablation (P<0.05). Conclusion: The electrophysiological characteristics are suggestive for focal AT originating from RAA during pregnancy. Under the guidance of 3-dimension activation mapping, no fluoroscopic RFA with irrigated-tip catheter is a safe and effective strategy for the treatment of focal RAAT during pregnancy.

Effects of interchange ratio on sludge reduction and microbial community structures in an anaerobic/anoxic/oxic process with combined anaerobic side-stream reactor

Oxic-settling-anaerobic (OSA) process is effective in minimizing sludge production, by inserting an anaerobic side-stream reactor (ASSR) in the recycling bypass. Interchange ratio (IR), the quantity ratio of sludge entering the ASSR to the sludge in the main stream reactors, is one of the most important parameters for OSA process. In the present study, a laboratory-scale anaerobic/anoxic/oxic (A²/O) process combined with an ASSR (A²/O-ASSR) was operated for 366 days in parallel with a conventional A²/O process to investigate the effects of IR on sludge reduction. IR was assigned values of 5%, 8%, 10%, and 15%, and the A²/O-ASSR process achieved 14.0%, 16.0%, 24.1%, and 13.7% of sludge reduction, respectively. At the optimum IR of 10%, high through-put sequencing analysis showed that the microbes responsible for pollutant removal and ubiquitous in wastewater treatment remained predominant in the two systems, and slow-growing microbes related to hydrolysis, nitrogen and phosphorus removal increased in the A²/O-ASSR process, which probably played a key role in sludge reduction. 40.6-58.6% of sludge reduction was caused by sludge decay in the ASSR. The tiny amount of extracellular polymeric substance released in the A²/O-ASSR process was subthreshold to cause remarkable sludge reduction.

Population structure and genetic diversity of Setosphaeria turcica from corn in Heilongjiang province, China

AIM

The aims of this study were to identify races and mating types of Setosphaeria turcica causing northern corn leaf blight in Heilongjiang province of China and analyse the genetic diversity of S. turcica isolates using SSR markers.

METHODS AND RESULTS

Based on gene-for-gene interactions, 13 races of S. turcica (races 0, 1, 2, 3, 12, 13, 23, 123, N, 1N, 12N, 3N and 23N) were isolated from infected corn plants in Heilongjiang province. Races 0 and 1 were the predominant races, and race 23N was identified for the first time in the region. Using two pairs of specific primers, three mating types, 'a', 'Aa' and 'A', were identified, with 'a' being the predominant mating type. SSR markers were used to analyse genetic diversity of 60 S. turcica isolates. Five SSR primers were polymorphic, which resulted in 45 reproducible bands with 2-15 bands for each primer. Cluster analysis separated the isolates into five groups at a similarity coefficient of 0·84. Analysis of molecular variance showed that there was significant correlation between SSR groups and mating type of the isolates. No significant correlation was found between SSR groups and physiological races or geographical location of the isolates.

CONCLUSIONS

The work reported that races 0 and 1 were the predominant races, and race 23N was identified for the first time in Heilongjiang province with 'a' being the predominant mating type. There was significant correlation between SSR groups and mating type of S. turcica isolates.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our results provide information on population structure and genetic diversity of S. turcica causing Northern corn leaf blight, which will facilitate the development of effective disease management programs.

Cardiovascular disease-related mortality and factors associated with cardiovascular events in the TREAT Asia HIV Observational Database (TAHOD)

OBJECTIVES

With aging of the HIV-positive population, cardiovascular disease (CVD) increasingly contributes to morbidity and mortality. We investigated CVD-related and other causes of death (CODs) and factors associated with CVD in a multi-country Asian HIV-positive cohort.

METHODS

Patient data from 2003-2017 were obtained from the Therapeutics, Research, Education and AIDS Training in Asia (TREAT Asia) HIV Observational Database (TAHOD). We included patients on antiretroviral therapy (ART) with > 1 day of follow-up. Cumulative incidences were plotted for CVD-related, AIDS-related, non-AIDS-related, and unknown CODs, and any CVD (i.e. fatal and nonfatal). Competing risk regression was used to assess risk factors of any CVD.

RESULTS

Of 8069 patients with a median follow-up of 7.3 years [interquartile range (IQR) 4.4-10.7 years], 378 patients died [incidence rate (IR) 6.2 per 1000 person-years (PY)], and this total included 22 CVD-related deaths (IR 0.36 per 1000 PY). Factors significantly associated with any CVD event (IR 2.2 per 1000 PY) were older age [sub-hazard ratio (sHR) 2.21; 95% confidence interval (CI) 1.36-3.58 for age 41-50 years; sHR 5.52; 95% CI 3.43-8.91 for ≥ 51 years, compared with < 40 years], high blood pressure (sHR 1.62; 95% CI 1.04-2.52), high total cholesterol (sHR 1.89; 95% CI 1.27-2.82), high triglycerides (sHR 1.55; 95% CI 1.02-2.37) and high body mass index (BMI) (sHR 1.66; 95% CI 1.12-2.46). CVD crude IRs were lower in the later ART initiation period and in lower middle- and upper middle-income countries.

CONCLUSIONS

The development of fatal and nonfatal CVD events in our cohort was associated with older age, and treatable risk factors such as high blood pressure, triglycerides, total cholesterol and BMI. Lower CVD event rates in middle-income countries may indicate under-diagnosis of CVD in Asian-Pacific resource-limited settings.

Quantitative trait loci mapping of the stigma exertion rate and spikelet number per panicle in rice (Oryza sativa L.)

The stigma exertion rate is a polygenic inherited trait that is important for increased seed yield in hybrid rice breeding. To identify quantitative trait loci (QTL) associated with high stigma exertion rate, we conducted QTL mapping using 134 recombinant inbred lines derived from XieqingzaoB and Zhonghui9308, which have high and low stigma exertion rates, respectively. A total of eight QTLs (qSES6, qSSE11, qDSE1a, qDSE1b, qDSE10, qDSE11, qTSE1, and qTSE11) for single stigma exertion, double stigma exertion, and total stigma exertion were detected. The locations of qSSE11 and qTSE11 have not been previously reported, and the qDSE11 allele from parent XQZB exhibited a positive additive effect. In addition, three QTLs (qSNP1, qSNP3a, and qSNP3b), for spikelet number per panicle were identified. Of note, one QTL (qSNP1) was detected in two different environments (Hainan and Zhejiang). To evaluate the advantage of exerted stigma for cross-pollination, single, dual, and total stigma exertion should be considered separately for future genetic improvement in the production of rice hybrid seeds. In addition, this study provides information for fine mapping, gene cloning, and marker assisted selection, with emphasis on the latter.

Ultrasound Findings of Intraductal Papillary Neoplasm in Bile Duct and the Added Value of Contrast-Enhanced Ultrasound

PURPOSE

To investigate the imaging features of intraductal papillary neoplasm in bile duct (IPNB) on baseline ultrasound and contrast-enhanced ultrasound (CEUS).

MATERIALS AND METHODS

The imaging features on baseline ultrasound and CEUS in 16 pathologically proven IPNB lesions in 15 patients were retrospectively analyzed. Real-time contrast specific modes and contrast agent of SonoVue were used for CEUS.

RESULTS

Bile duct dilation was present in all patients. The mean lengths for the intraductal papillary adenomas and adenocarcinomas were 2.5 ± 1.1 (range, 1.2 - 4.2 cm) and 5.6 ± 2.0 cm (range, 3.3 - 9.8 cm) (P = 0.004). Three imaging types of IPNB on ultrasound were depicted: bile duct dilation with intraductal mass (n = 8), bile duct dilation without intraductal mass (n = 3), and cystic-solid mixed type (n = 5). On CEUS, solid components of 13 lesions appeared hyper- (n = 12) or iso-enhancement (n = 1) in the arterial phase whereas all showed hypo-enhancement in the portal and late phases. For 3 lesions of bile duct dilation without intraductal mass, CEUS showed non-enhancement during all phases. Pre-surgical CEUS and conventional ultrasound made correct diagnoses in 12 (75.0 %) and 5(31.3 %) of 16 IPNBs respectively (P = 0.04). For CECT, correct diagnosis was also achieved in 12 (75.0 %) of 16 lesions (P = 1.00, in comparison with CEUS).

CONCLUSIONS

IPNB should be taken into consideration when intraductal mass or cystic-solid mass with bile duct dilation, or remarkable bile duct dilation without intraductal mass, are found on US. Intraductal mass length > 3.0 cm is more commonly found in malignant IPNB. CEUS might facilitate the diagnosis of IPNB by easily excluding the possibility of commonly found sludge, nonshadowing stones, or blood clots.

Differential expression of luteinizing hormone receptor, androgen receptor and heat-shock protein 70 in the testis of long-distance transported mice

Spermatogenesis, is a complex process of precisely regulated intracellular events, where it is affected by many factors. Long-distance transport of animals is one of the stressors that may influence spermatogenesis and sperm quality. The present study chose luteinizing hormone receptor (LHR), androgen receptor (AR), and heat-shock protein 70 (HSP70) as our target genes to investigate their mRNA and protein expression in the testes of long-distance transported (about 1000 km) mice. Histological analysis showed that there was a reduction in the thickness of the seminiferous epithelium in the transported mice, and a significant decrease in body weight and sperm count in the epididymis was also observed. mRNA expression was determined by QPCR in the testis of transported and control mice. The levels for AR decreased significantly in transported mice. LHR and HSP70 expression in the testes of the transported mice was slightly higher than that of control mice but did not reach a significant level. A similar tendency of protein expression was also observed by Western blot analysis. The levels of LHR and HSP70 increased slightly after transportation. However, none of the changes were statistically significant compared with the control mice. In conclusion, long-distance transport has an adverse effect on reproductive organs and spermatozoa in adult mice.

Study of the sludge reduction in an oxic-settling-anaerobic activated sludge process based on UNITANK

An oxic-settling-anaerobic process (OSA) can effectively reduce sludge production, but most of the research studies on the OSA process have been either under laboratory test conditions or based on synthetic wastewater, which cannot fully reflect the performance and sludge reduction efficiency in existing OSA process. Thus, aiming at examining the sludge reduction efficiency and the stability of the OSA process, UNITANK and UNITANK-OSA processes were performed in a 120 m(3)/d pilot-scale system using actual sewage. The results indicate that UNITANK-OSA achieved a 48% reduction of the sludge compared to the reduction due to UNITANK, not considering the accumulation of the effluent-suspended solids. The effluent quality was not found to change significantly, except that the total phosphorus concentration increased slightly. The extracellular polymeric substances metal floc theory may, to some extent, explain this reduction in this study. The OSA process could be used to reform the classic wastewater treatment process to get lower sludge mass.

Optimization of complex conditions by response surface methodology for APAM-oil/water emulsion removal from aqua solutions using nano-sized TiO2/Al2O3 PVDF ultrafiltration membrane

This paper studies the cumulative effect of various parameters, namely anionic polyacrylamide (APAM) concentration, oil concentration, pH, trans-membrane pressure (TMP), and total dissolved solid (TDS), and obtains optimal parameters for the minimum relative flux (J/J(0)) declining in aqueous solutions with response surface methodology (RSM). In order to analyze the mutual interaction and optimal values of parameters affecting ultrafiltration, a central composite rotatable design (CCRD), one method of RSM, was employed. The analysis of variance (ANOVA) of the cubic polynomial model demonstrated that this model was highly significant and reliable. The results show that the effect of APAM and oil on J/J(0) has an inverse trend with pH value increasing. Moreover, the mutual interaction of initial APAM (oil) concentration (C(APAM(oil))) and pH (TMP) were negligible, while the mutual interaction of C(APAM) and C(oil) has an obvious effect, i.e. the effect of initial feed C(APAM) became more important at higher values of initial feed C(oil), and the J/J(0) was only about 4%. The favorable operate conditions in this ultrafiltration process were at low C(APAM), C(oil), pH, and TMP, which agreed with the conclusions of many authors, while considering water production, C(APAM) and C(oil) < 50 mg/L, pH < 4, and TMP < 0.075 MPa could be accepted.

Comparative study of serology and histology based detection of Helicobacter pylori infections: a large population-based study of 7,241 subjects from China

Two detection methods for H. pylori infections, i.e. serological antibody titer measurements by Hp-ELISA and histological scoring by HE staining, have been compared to investigate the relationship between the diagnosis methods, to clarify the application scope of each diagnosis method and to determine its influencing factors. In the 7,241 subjects who participated in gastric cancer screening, H. pylori infection rate was 70.14% by the Hp-HE method and 41.87% by the Hp-ELISA method when 34EIU was recognized as the cut-off value. The IgG titers increased with the elevation of HE scores; however, the two methods were not closely correlated among those in different gastric disease status. Age, gender and drinking status did not have significant impact on the relationship between the two methods; however, smoking status seemed to significantly influence the correlation of the two diagnosis methods. In conclusion, it was necessary to reevaluate the cut-off value when using ELISA test kits in different population groups. In most cases, the results of two H. pylori infection diagnosis methods show high correlation. However, this relationship can be affected by smoking and gastric diseases status. Additionally, the dynamic change of H. pylori antibody titers is an indicator of gastric disease development.

Biological evaluation of collagen-chitosan scaffolds for dermis tissue engineering

Three-dimensional collagen-chitosan scaffolds were fabricated with type I collagen and chitosan through freeze drying and glutaraldehyde cross-linking. Dermal fibroblasts were isolated from neonatal Sprague-Dawley rat skin by dispase II/collagenase I digestion. The fibroblasts were then seeded into the scaffolds to construct tissue-engineered dermis. The microstructure of the scaffolds as well as the fibroblasts' proliferation, cytokine secretion and cell cycle were investigated. Flow cytometry analysis indicated that cells in the scaffolds proliferated steadily. IL-6 concentration measurement by the ELISA test suggested that the scaffolds could promote secretion of the fibroblasts' cytokine. These results show that the fibroblasts and the scaffolds interact well with each other, and the fibroblasts have better proliferation ability and biological activity in the scaffolds than in monolayer culture. The scaffolds are a promising candidate for tissue repair and regeneration with enhanced biostability and good cytocompatibility.