The cardiovascular system at high altitude: A bibliometric and visualization analysis

BACKGROUND

When exposed to high-altitude environments, the cardiovascular system undergoes various changes, the performance and mechanisms of which remain controversial.

AIM

To summarize the latest research advancements and hot research points in the cardiovascular system at high altitude by conducting a bibliometric and visualization analysis.

METHODS

The literature was systematically retrieved and filtered using the Web of Science Core Collection of Science Citation Index Expanded. A visualization analysis of the identified publications was conducted employing CiteSpace and VOSviewer.

RESULTS

A total of 1674 publications were included in the study, with an observed annual increase in the number of publications spanning from 1990 to 2022. The United States of America emerged as the predominant contributor, while Universidad Peruana Cayetano Heredia stood out as the institution with the highest publication output. Notably, Jean-Paul Richalet demonstrated the highest productivity among researchers focusing on the cardiovascular system at high altitude. Furthermore, Peter Bärtsch emerged as the author with the highest number of cited articles. Keyword analysis identified hypoxia, exercise, acclimatization, acute and chronic mountain sickness, pulmonary hypertension, metabolism, and echocardiography as the primary research hot research points and emerging directions in the study of the cardiovascular system at high altitude.

CONCLUSION

Over the past 32 years, research on the cardiovascular system in high-altitude regions has been steadily increasing. Future research in this field may focus on areas such as hypoxia adaptation, metabolism, and cardiopulmonary exercise. Strengthening interdisciplinary and multi-team collaborations will facilitate further exploration of the pathophysiological mechanisms underlying cardiovascular changes in high-altitude environments and provide a theoretical basis for standardized disease diagnosis and treatment.

A Convenient and Effective Preoxygenation Technique for Prolonging Deep Inspiration Breath-Hold Duration With a Venturi Mask With a 50% Oxygen Concentration

PURPOSE

Voluntary deep inspiration breath-hold (DIBH) is commonly used in radiation therapy (RT), but the short duration of a single breath-hold, estimated to be around 20 to 40 seconds, is a limitation. This prospective study aimed to assess the feasibility and safety of using a simple preoxygenation technique with a Venturi mask to prolong voluntary DIBH.

METHODS AND MATERIALS

The study included 33 healthy volunteers and 21 RT patients. Preoxygenation was performed using a Venturi mask with a 50% oxygen concentration. Paired t tests compared the duration of a single DIBH in room air and after 5, 15, and 30 minutes of preoxygenation in healthy volunteers. Sustainability of breath-hold and tolerability of heart rate and blood pressure were assessed for multiple DIBH durations in both volunteers and patients.

RESULTS

In healthy volunteers, a 15-minute preoxygenation significantly prolonged the duration of a single DIBH by 24.95 seconds compared with 5-minute preoxygenation (89 ± 27.76 vs 113.95 ± 30.63 seconds; P < .001); although there was a statistically significant increase in DIBH duration after 30-minute preoxygenation, it was only extended by 4.95 seconds compared with 15-minute preoxygenation (113.95 ± 30.63 vs 118.9 ± 29.77 seconds; P < .01). After 15-minute preoxygenation, a single DIBH lasted over 100 seconds in healthy volunteers and over 80 seconds in RT patients, with no significant differences among 6 consecutive cycles of DIBH. Furthermore, there were no significant differences in heart rate or blood pressure after DIBHs, including DIBH in room air and 6 consecutive DIBHs after 15-minute preoxygenation (all P > .05).

CONCLUSIONS

Preoxygenation with a 50% oxygen concentration for 15 minutes effectively prolongs the duration of 6 cycles of DIBH both in healthy volunteers and RT patients. The utilization of a Venturi mask to deliver 50% oxygen concentration provides a solution characterized by its convenience, good tolerability, and effectiveness.

[Effectiveness of 13-valent pneumococcal conjugate vaccine against invasive disease caused by serotype 19A in children: a meta-analysis]

Objective: Using Meta-analysis to evaluate the vaccine effectiveness of 13-valent pneumococcal conjugate vaccine (PCV13) against invasive Streptococcus pneumoniae disease (IPD) caused by serotype 19A in children <5 years old. Methods: "Streptococcus pneumoniae infection""invasive pneumococcal disease""13-valent pneumococcal polysaccharide conjugate vaccine""PCV13""effectiveness""infant""child" and related terms were searched from China National Knowledge Infrastructure (CNKI), WANFANG DATA, PubMed, SCOPUS and Web of science with no limited on language, region and research institution. The retrieval time was limited from January 2010 to February 2023 and cohort study, case-control study and randomized controlled trial were included. Data were extracted from eligible studies by two independent reviewers, and after study quality assessment by NOS scale, Meta-analysis was completed using Stata 16.0 software. Results: A total of 2 340 related literatures were searched, and 10 literatures were finally included, including 5 case-control studies and 5 indirect cohort studies, which showed good literature quality. The vaccine effectiveness against serotype 19A IPD of PCV13 in children was 83.91% (95%CI: 78.92%-88.89%), and the subgroup analysis (P=0.240) showed there was no significant difference among the case-control study (VE=87.34%, 95%CI:79.74%-94.94%) and the indirect cohort study (VE=81.30%, 95%CI:74.69%-87.92%). The funnel plot and Egger test suggested that the possibility of publication bias was small. Conclusion: The present evidence indicates that PCV13 has a good vaccine effectiveness against serotype 19A IPD in children, and it is recommended to further increase the vaccination rate of PCV13 to reduce the disease burden of IPD in children <5 years old.

[Clinical and pathological features of 20 cases of congenital hepatic fibrosis]

Objective: To investigate the clinical and pathological features of congenital hepatic fibrosis (CHF). Methods: The clinical and pathological findings of 20 patients diagnosed with CHF from 2017 to 2023 were retrospectively analyzed. Results: Among the 20 patients, 8 were males and 12 were females with a median age of 21.5 years. Mostly patients were admitted to the hospital with cirrhosis, portal hypertension and upper gastrointestinal bleeding. Pathological features were diffuse fibrosis in the portal area, formation of fibrous septa of varying width, segmentation of the liver parenchyma, with hyperplasia of small bile ducts. Among them, 1 case (5%) was complicated with Caroli's disease, and 1 case (5%) was HNF1α hepatocellular adenoma. IHC GS showed that was positively expressed in acinar region 3 in 75% cases. Conclusion: CHF is mainly manifested by portal hypertension and its complications. Histopathology is the gold standard for diagnosis. The possibility of CHF should be considered first in children and adolescents with portal hypertension but no history of hepatitis, and complicated kidney disease. The positive pattern of acinus-3 region of GS in IHC is helpful for the diagnosis of CHF.

Early Enteral Nutrition and Sepsis-Associated Acute Kidney Injury: A Propensity Score Matched Cohort Study Based on the MIMIC-III Database

PURPOSE

We aimed to analyze the optimal timing of enteral nutrition (EN) in the treatment of sepsis and its effect on sepsis-associated acute kidney injury (SA-AKI.).

MATERIALS AND METHODS

The MIMIC-III database was employed to identify patients with sepsis who had received EN. With AKI as the primary outcome variable, receiver operating characteristic (ROC) curves were utilized to calculate the optimal cut-off time of early EN (EEN). Propensity score matching (PSM) was employed to control confounding effects. Logistic regressions and propensity score-based inverse probability of treatment weighting were utilized to assess the robustness of our findings. Comparisons within the EEN group were performed.

RESULTS

2364 patients were included in our study. With 53 hours after intensive care units (ICU) admission as the cut-off time of EEN according to the ROC curve, 1212 patients were assigned to the EEN group and the other 1152 to the delayed EN group. The risk of SA-AKI was reduced in the EEN group (odds ratio 0.319, 95% confidence interval 0.245-0.413, p<0.001). The EEN patients received fewer volumes (mL) of intravenous fluid (IVF) during their ICU stay (3750 mL vs. 5513.23 mL, p<0.001). The mediating effect of IVF was significant (p<0.001 for the average causal mediation effect). No significant differences were found within the EEN group (0-48 hours vs. 48-53 hours), except that patients initiating EN within 48 hours spent fewer days in ICU and hospital.

CONCLUSION

EEN is associated with decreased risk of SA-AKI, and this beneficial effect may be proportionally mediated by IVF volume.

A comparative transcriptomic analysis reveals a coordinated mechanism activated in response to cold acclimation in common vetch (Vicia sativa L.)

BACKGROUND

Due to its strong abiotic stress tolerance, common vetch is widely cultivated as a green manure and forage crop in grass and crop rotation systems. The comprehensive molecular mechanisms activated in common vetch during cold adaptation remain unknown.

RESULTS

We investigated physiological responses and transcriptome profiles of cold-sensitive (Lanjian No. 1) and cold-tolerant (Lanjian No. 3) cultivars during cold acclimation to explore the molecular mechanisms of cold acclimation. In total, 2681 and 2352 differentially expressed genes (DEGs) were identified in Lanjian No. 1 and Lanjian No. 3, respectively; 7532 DEGs were identified in both lines. DEGs involved in "plant hormone signal transduction" were significantly enriched during cold treatment, and 115 DEGs involved in cold-processed hormone signal transduction were identified. Common vetch increased the level of indoleacetic acid (IAA) by upregulating the transcriptional regulator Aux/IAA and downregulating GH3, endowing it with stronger cold tolerance. An auxin-related DEG was overexpressed in yeast and shown to possess a biological function conferring cold tolerance.

CONCLUSION

This study identifies specific genes involved in Ca²⁺ signaling, redox regulation, circadian clock, plant hormones, and transcription factors whose transcriptional differentiation during cold acclimation may improve cold tolerance and contributes to the understanding of common and unique molecular mechanisms of cold acclimation in common vetch. The candidate genes identified here also provide valuable resources for further functional genomic and breeding studies.

[Epidemiological characteristics and spatiotemporal clustering of hepatitis A in Zhejiang Province from 2010 to 2019]

Objective: To analyze the epidemiological characteristics and spatiotemporal clustering of hepatitis A in Zhejiang Province from 2010 to 2019. Methods: The data of hepatitis A incidence in Zhejiang Province from 2010 to 2019 were collected from the infectious disease surveillance system of China Information System for Disease Control and Prevention. ArcGIS 10.7 software was used for spatial autocorrelation analysis. SaTScan 9.6 software was used for spatiotemporal scanning analysis. SPSS 25.0 software was used for additional analysis. Results: Zhejiang Province has reported 5 465 cases of hepatitis A in 2010-2019 years, with an average annual incidence rate of 1.00/100 000, and periodicity and seasonality are not obvious. The incidence of male was higher than that of female (P=0.023), and the highest incidence rate was 50-59 years old. Spatial autocorrelation analysis showed that there was a positive spatial correlation between the incidence of hepatitis A in Zhejiang Province from 2010 to 2017, with the weakest correlation in 2010 (Moran's I =0.103, Z=1.769, P=0.049), and the strongest correlation in 2016 (Moran's I=0.328, Z=4.979, P=0.001). Spatiotemporal scanning analysis showed that there was spatial aggregation of hepatitis A in Zhejiang Province from 2010 to 2019, with a total of three aggregation areas identified. Among them, the mostly aggregation area was concentrated in Xiangshan county of Ningbo city, which covered 10 counties (cities and districts), including Ninghai county and Yinzhou district, and appeared from January 1 to June 30, 2012. Conclusion: The incidence level of hepatitis A in Zhejiang Province shows a stable fluctuation trend from 2010 to 2019, and the seasonal regularity is not obvious. The population group aged 50-59 years old is the key population. There is spatial aggregation in the epidemic situation of hepatitis A. Targeted prevention and control measures of hepatitis A should be done based on the law of spatiotemporal aggregation and local incidence.

Targeted Inhibition of HK-II Reversed the Warburg Effect to Improve the Radiosensitivity of Laryngeal Carcinoma

Purpose

Hexokinase-II (HK-II) is the key enzyme in the first rate-limiting step of glycolysis that catalyzes the conversion of glucose to glucose-6-phosphate. Here, we examined the association between HK-II expression and radioresistance in laryngeal carcinoma and whether the inhibition of HK-II expression can enhance the radiosensitivity of these tumors.

Methods

The effects of HK-II small interfering RNA (siRNA) on the radiosensitivity of Tu212 cells were examined in vitro and in vivo in a mouse model. Cells were irradiated using a 6-MV linear accelerator. The cell viability, cell survival, proliferation, apoptosis, and cell cycle of Tu212 cells were evaluated using trypan blue staining, colony formation assays, CCK-8 assays, and flow cytometry, respectively. Oxygen consumption, lactic acid production, glucose consumption, and the ATP level of Tu212 cells were also examined. The expression of glycolytic and regulatory enzymes involved in the tricarboxylic acid cycle was assessed using Western blotting.

Results

The HK-II siRNA and X-ray combination treatment led to a significantly greater reduction of cell viability, inhibition of cell survival and proliferation, increased apoptosis, and increased G2 phase arrest compared to either treatment alone (all, P<0.01). HK-II siRNA increased the oxygen consumption rate of cells, significantly inhibited lactic acid production and glucose consumption, and significantly suppressed the upregulation of HK-II, pyruvate kinase M2 (PKM2), pyruvate dehydrogenase (PDH), phosphofructokinase platelet (PFKP), lactate dehydrogenase (LD), and citrate synthase (CS) (all, P<0.01).

Conclusion

The inhibition of HK-II by siRNA enhances the radiosensitivity of laryngeal carcinoma Tu212 cells by inhibiting glycolysis and partially inhibiting oxidative phosphorylation.

Radiosensitizing effects of curcumin alone or combined with GLUT1 siRNA on laryngeal carcinoma cells through AMPK pathway-induced autophagy

In this study, we investigated the ability of curcumin alone or in combination with GLUT1 siRNA to radiosensitize laryngeal carcinoma (LC) through the induction of autophagy. Protein levels in tumour tissues and LC cells were measured by immunohistochemistry and Western blotting. In vitro, cell proliferation, colony formation assays, cell death and autophagy were detected. A nude mouse xenograft model was established through the injection of Tu212 cells. We found that GLUT1 was highly expressed and negatively associated with autophagy-related proteins in LC and that curcumin suppressed radiation-mediated GLUT1 overexpression in Tu212 cells. Treatment with curcumin, GLUT1 siRNA, or the combination of the two promoted autophagy. Inhibition of autophagy using 6-amino-3-methypourine (3-MA) promoted apoptosis after irradiation or treatment of cells with curcumin and GLUT1 siRNA. 3-MA inhibited curcumin and GLUT1 siRNA-mediated non-apoptotic programmed cell death. The combination of curcumin, GLUT1 siRNA and 3-MA provided the strongest sensitization in vivo. We also found that autophagy induction after curcumin or GLUT1 siRNA treatment implicated in the AMP-activated protein kinase-mTOR-serine/threonine-protein kinase-Beclin1 signalling pathway. Irradiation primarily caused apoptosis, and when combined with curcumin and GLUT1 siRNA treatment, the increased radiosensitivity of LC occurred through the concurrent induction of apoptosis and autophagy.

Isolation and identification of bioactive substance 1-hydroxyphenazine from Pseudomonas aeruginosa and its antimicrobial activity

A strain named as Pseudomonas aeruginosa 2016NX1, which could produce phenazine and cereusitin, was isolated from the root of Millettia specisoa. Phenazines were extracted, isolated and purified by chloroform, thin-layer chromatography, column chromatography and high-performance liquid chromatography. Then the purified materials were identified by analysis of nuclear magnetic resonance. The major yellow component is 1-hydroxyphenazine and the minor blue component is cereusitin A. The tests of antimicrobial activity of yellow component showed that the growth of several common plant pathogenic fungi and bacteria (such as Cochliobolus miyabeanus, Diaporthe citri, Salmonella sp., Klebsiella oxytoca) could be strongly inhibited. This study suggested that Pseudomonas aeruginosa strain 2016NX1 had a significant potential for biological control of phytopathogenic fungi. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, one bioactive substance from Pseudomonas aeruginosa 2016NX1 was identified and its antimicrobial activity was verified. This study demonstrated that one bioactive substance from P. aeruginosa can strongly inhibit the growth of plant pathogenic fungi and bacteria. This study suggested that P. aeruginosa strain 2016NX1 has a significant potential for biological control of phytopathogenic fungi.

Effect of combination of curcumin and GLUT-1 AS-ODN on radiosensitivity of laryngeal carcinoma through regulating autophagy

BACKGROUND

This study is to explore the role of curcumin and GLUT-1 antisense oligodeoxynucleotides (AS-ODN) on autophagy modulation-initiated radiosensitivity.

METHODS

BALB/c mice were employed to establish xenograft model using Tu212 cell. The expression of autophagy- and apoptosis-related proteins was determined by WB. Autophagosome was observed under transmission electron microscope. Apoptosis of tumor tissue were detected by TUNEL staining.

RESULTS

Combinations of curcumin and GLUT-1 AS-ODN with 10 Gy inhibited the tumor growth by inducing apoptosis of laryngeal cancer cells followed with the enhancement of autophagy. 3-MA also had a promotion effect on irradiation-mediated growth inhibition possibly by depressing PI3K and on curcumin/GLUT-1 AS-ODN-mediated growth inhibition potentially by regulating autophagic events. Of note, a de-escalation of radiotherapy dose (5 Gy) along with curcumin, GLUT-1 AS-ODN or 3-MA produced a stronger effect than high dosage of radiotherapy (10 Gy) alone.

CONCLUSIONS

Curcumin and GLUT-1 AS-ODN improve the radiosensitivity of laryngeal carcinoma through regulating autophagy and inducing apoptosis.

GLUT-1 siRNA Enhances Radiosensitization Of Laryngeal Cancer Stem Cells Via Enhanced DNA Damage, Cell Cycle Redistribution, And Promotion Of Apoptosis In Vitro And In Vivo

Background

Radiotherapy does not show good efficacy against laryngeal cancer due to radioresistance. Cancer stem cells (CSCs) are considered among the causes of radioresistance. Inhibition of glucose transporter-1 (GLUT-1) using GLUT-1 small interfering RNA (siRNA) may enhance the radiosensitivity of laryngeal cancer cells, but the underlying cellular mechanisms remain unclear.

Methods

The CD133⁺-Hep-2R cell line was established with repeated irradiation and magnetic-activated cell sorting. The effects of irradiation on CD133⁺-Hep-2R cells were examined by CCK-8 assay, Transwell assay, quantitative real-time polymerase chain reaction (RT-PCR), and Western blotting. The effects of GLUT-1 siRNA on the radiosensitivity of CD133⁺-Hep-2/2R cells were examined by RT-PCR, Western blotting, CCK-8 assay, colony formation assay, and Transwell assay in vitro and in a xenograft tumor model in nude mice. The cellular mechanism of enhanced radiosensitivity associated with GLUT-1 siRNA was investigated. The cell cycle and apoptosis rate were analyzed by flow cytometry, and the repair capability was examined by determining the levels of RAD51 and DNA-PKcs.

Results

CD133⁺-Hep-2/2R cells showed stronger proliferation, lower apoptosis rate, lower percentage of G0/G1 phase cells, higher percentages of S and G2/M phase cells, and higher expression levels of GLUT-1 than Hep-2/2R cells. Transfection with GLUT-1 siRNA inhibited the proliferation and invasive capability of CD133⁺-Hep-2R cells by inhibiting GLUT-1 expression, which also caused a redistribution of the cell cycle (higher proportion of cells in the G0/G1 phase and lower proportion in the S and G2/M phases), increased the apoptosis rate, and reduced DNA repair capability by suppressing RAD51 and DNA-PKcs expression.

Conclusion

The results of this study suggest that GLUT-1 siRNA can enhance the radiosensitivity of CD133⁺-Hep-2R cells by inducing a redistribution of cell cycle phases, inhibiting DNA repair capability, and increasing apoptosis. Inhibition of GLUT-1 may have therapeutic potential for interventions to increase the radiosensitivity of laryngeal CSCs.

Construction of a GLUT-1 and HIF-1α gene knockout cell model in HEp-2 cells using the CRISPR/Cas9 technique

Background

Glucose transporter (GLUT)-mediated glucose uptake is an important process in the development of laryngeal carcinoma, one of the most common malignancies of the head and neck. GLUT-1, together with HIF-1α, is also an indicator of hypoxia. Both proteins play a critical role in glucose uptake and glycolysis in laryngeal carcinoma cells under hypoxic stress. A double gene knockout model in which HIF-1α and GLUT-1 are no longer expressed can provide important information about carcinogenesis in laryngeal carcinoma.

Purpose

In this study we used the CRISPR/Cas 9 system to induce HIF-1α and GLUT-1 double gene knockout in HEp-2 cells and then used the knocked-out cells to study the role of these markers in laryngeal carcinoma, including in chemoradioresistance.

Methods

High-grade small-guide RNAs (sgRNAs) of HIF-1α and GLUT-1 were designed using an online tool and inserted into the pUC57-T7-gRNA vector. The recombinant plasmids were transfected into HEp-2 cells and positive cells were screened using the dilution method. Gene mutation and expression were determined by sequence analysis and immunoblotting.

Results

In HIF-1α and GLUT-1 double gene knockout HEp-2 cells, a 171-bp deletion in the HIF-1α genomic sequence was detected, whereas multiple base insertions resulted in frameshift mutations in the GLUT-1 gene. Neither HIF-1α nor GLUT-1 protein was expressed in positive cells. The proliferation, migration, and invasion of HEp-2 cells were significantly decreased afterward. The possible mechanism may be that the inhibition PI3K/AKT/mTOR pathway by HIF-1α and GLUT-1 double gene knockout using CRISPR/Cas9 technique lead to reduction of glucose uptake and lactic acid generation.

Conclusion

Our HIF-1α and GLUT-1 double gene knockout HEp-2 cell model, obtained using a CRISPR/Cas9-based system, may facilitate studies of the pathogenesis of laryngeal carcinoma.

In vivo evaluation of the effects of simultaneous inhibition of GLUT-1 and HIF-1α by antisense oligodeoxynucleotides on the radiosensitivity of laryngeal carcinoma using micro 18F-FDG PET/CT

Purpose

Hypoxia-inducible factor 1α (HIF-1α) and glucose transporter-1 (GLUT-1) are two important hypoxic markers associated with the radioresistance of cancers including laryngeal carcinoma. We evaluated whether the simultaneous inhibition of GLUT-1 and HIF-1α expression improved the radiosensitivity of laryngeal carcinoma. We explored whether the expression of HIF-1α and GLUT-1 was correlated with 2′-deoxy-2’-[18F]fluoro-D-glucose (¹⁸F-FDG) uptake and whether ¹⁸F-FDG positron emission tomography-computed tomography (PET/CT) was appropriate for early evaluation of the response of laryngeal carcinoma to targeted treatment in vivo.

Materials and Methods

To verify the above hypotheses, an in vivo model was applied by subcutaneously injecting Hep-2 (2 × 107/mL × 0.2 mL) and Tu212 cells (2 × 107/mL × 0.2 mL) into nude mice. The effects of HIF-1α antisense oligodeoxynucleotides (AS-ODNs) (100 μg) and GLUT-1 AS-ODNs (100 μg) on the radiosensitivity of laryngeal carcinoma were assessed by tumor volume and weight, microvessel density (MVD), apoptosis index (AI) and necrosis in vivo based on a full factorial (2³) design. ¹⁸F-FDG-PET/CT was taken before and after the treatment of xenografts. The relationships between HIF-1α and GLUT-1 expression and ¹⁸F-FDG uptake in xenografts were estimated and the value of ¹⁸F-FDG-PET/CT was assessed after treating the xenografts.

Results

10 Gy X-ray irradiation decreased the weight of Hep-2 xenografts 8 and 12 days after treatment, and the weights of Tu212 xenografts 8 days after treatment. GLUT-1 AS-ODNs decreased the weight of Tu212 xenografts 12 days after treatment. There was a synergistic interaction among the three treatments (GLUT-1 AS-ODNs, HIF-1α AS-ODNs and 10Gy X-ray irradiation) in increasing apoptosis, decreasing MVD, and increasing necrosis in Hep-2 xenografts 8 days after treatment (p < 0.05) and in Tu212 xenografts 12 days after treatment (p < 0.001). Standardized uptake value (tumor/normal tissue)( SUVmaxT/N) did not show a statistically significant correlation with GLUT1 and HIF-1α expression and therapeutic effect (necrosis, apoptosis).

Conclusions

Simultaneous inhibition of HIF-1α and GLUT-1 expression might increase the radiosensitivity of laryngeal carcinoma, decreasing MVD, and promoting apoptosis and necrosis. ¹⁸F-FDG-PET/CT wasn't useful in evaluating the therapeutic effect on laryngeal cancer in this animal study.

[Complications of critically ill children supported by venoarterial extracorporeal membrane oxygenation]

OBJECTIVE

To study the complications occurred in the process of venoarterial extracorporeal membrane oxygenation (VA-EMCO) in critically ill children.

METHOD

To analyze retrospectively 25 children who were admitted to PICU of Children's Hospital of Fudan University from December 2011 to December 2015. They were all treated with VA-ECMO with incision and catheterization in right internal carotid artery and jugular vein. Complications were recorded during ECMO process.

RESULT

The duration of ECMO treatment was 14 to 567 h (153 (112, 204) h). Seventeen cases (68%) withdrew from ECMO successfully and 15 cases (60%) survived to discharge. Thirty-three complications occurred during ECMO treatment. Of which, mechanical complications occurred 9 times, including oxygenator leakage (n=3), hemolysis (n=2), water tank failure (n=2), pump head rupture (n=1) and piping thrombosis (n=1). Somatic complications appeared 24 times, including neurological complications (n=8) which included cerebral infarction (n=2), convulsions (n=2), intracranial hemorrhage (n=2), thrombosis after ligation of internal jugular vein (n=1) and cerebral atrophy (n=1); bleeding complications (n=8) which included bleeding at puncture sites (n=4), ECMO canalized site bleeding (n=3), and spontaneous (n=1), intracranial hemorrhage or hematoma cases(n=2) in mechanical complications; acute kidney injury (n=5) and microcirculation thrombosis (n=3).

CONCLUSION

ECMO technique may cause complications, which mainly include neurological, mechanical and clotting complications. Advanced equipments and materials and well-managed teamwork are helpful in decreasing complications.

[Effects and mechanisms of high-volume hemofiltration on endotoxin-induced acute lung injury of piglets]

Objective: To compare the effects of high-volume hemofiltration (HVHF) and continuous veno-venous hemofiltration (CVVH) on cardiopulmonary functions, lung fluid balance, lung damage and cytokine expression in endotoxin-induced acute lung injury piglet model, and to further evaluate the value of high-volume hemofiltration in acute lung injury. Method: Eighteen piglets were randomly divided into the control group (6 piglets), the CVVH group (6 piglets) and the HVHF group (6 piglets). By general anesthesia, the intravenous infusion of 0.15 mg/kg endotoxin were received in all the animals and induced acute lung injury.High-volume hemofiltration and continuous veno-venous hemofiltration were addressed to different groups.Subsequently, hemodynamic parameters (heart rate, mean arterial blood pressure, central venous pressure, pulse contour cardiac index, systemic venous resistance index and extravascular lung water index) as well as gas exchange and lung mechanics parameters (respiratory rate, partial pressure of carbon dioxide, partial pressure of oxygen/fraction of inspired oxygen, dynamic lung compliance and airway resistance) were intermittently measured.Lung tissues were collected for further analysis (the lung wet-to-dry weight ratio, lung injury scoring). The plasma protein levels of cytokines (interleukin(IL) -6, 10 and tumor necrosis factors alpha(TNF-α)) were also assessed.Two-way analysis of variance (ANOVA) and Bonferroni post-test were conducted to identify significant differences among the control, CVVH and HVHF group. Result: Compared with CVVH, HVHF had the capacity to improve significantly the index of Cdyn(HVHF (2.3±0.5) vs. CVVH (1.5±0.5) ml/(cmH(2)O·kg), 1 cmH(2)O=0.098 kPa, P<0.05)and Rrs(HVHF (22.0±1.9) vs.CVVH (29.5±1.5) cmH(2)O/(L·s), P<0.05)at the time of 6 h, and decreased lung water accumulation(index of EVLWI in HVHF (22.7±2.1) vs.CVVH (39.5±2.6) ml/m(2,) P<0.01) at the time of 6 h, and the plasma concentration of cytokines(IL-6, IL-10, TNF-α)in the HVHF group had an obvious decline compared with those in the CVVH group at the time of 6 h( (200±55) vs. (280±61), (74±17) vs. (102±21), (54±13) vs. (73±21) pg/ml, all P<0.05). The lung injury scoring of HVHF group was significantly lower than those of CVVH group((7.8±1.9) vs. (11.3±2.2) scores, P<0.05). Although the plasma concentration of cytokines(IL-6, IL-10, TNF-α) in the CVVH group were lower than those in the control group at the time of 6 h((374±55), (137±25), (98±17) pg/ml, all P<0.05), the indexes of respiratory function were not improved (all P<0.05). Conclusion: Different doses hemofiltration can reduce plasma inflammatory mediators indicators in piglets.Early high volume hemofiltration can improve respiratory function of piglets with endotoxin-induced acute lung injury and reduce lung injury pathological score.

In-vivo organ engineering: Perfusion of hepatocytes in a single liver lobe scaffold of living rats

Organ decellularization is emerging as a promising regenerative medicine approach as it is able to provide an acellular, three-dimensional biological scaffold material that can be seeded with living cells for organ reengineering. However this application is currently limited to donor-derived decellularized organs for reengineering in vitro and no study has been conducted for re-engineering the decellularized organ in vivo. We developed a novel technique of a single liver lobe decellularization in vivo in live animals. Using a surgical method to generate a by-pass circulation through the portal vein and infra-hepatic vena cava with a perfusion chamber system, we decellularized the single liver lobe and recellularized it with allogenic primary hepatocytes. Our results showed that the decellularization process in vivo can preserve the vascular structural network and functional characteristics of the native liver lobe. It allows for efficient recellularization of the decellularized liver lobe matrix with allogenic primary hepatocytes. Upon the re-establishment of blood circulation, the recellularized liver lobe is able to gain the function and the allogenic hepatocytes are able to secret albumin. Our findings provide a proof of principle for the in vivo reengineering of liver.

[Application of right jugular vessels to build extracorporeal membrane oxygenation for treating the critically ill children]

OBJECTIVE

To summarize the experience in applying a technique of inserting a cannula through right internal jugular vein and common carotid artery to build extracorporeal membrane oxygenation (ECMO) for critically ill children.

METHOD

The data of critically ill patients received ECMO support through right internal jugular vein and common carotid artery between December 2011 and December 2015 from Children's Hospital of Fudan University were analyzed retrospectively.The data included diagnosis, age, body weight, time of cannula and ECMO running, complication and prognosis.

RESULT

In total 28 patients received ECMO support, 3 patients of post-cardiac surgery with transthoracic cannula were excluded.Twenty-five patients inserted cannula through neck vessels were enrolled, 15 boys and 10 girls, the median age was 1.8 years (range, 1 d-13 years), the median weight was 12.0 (2.8-50.0) kg.All the cannula sites were right internal jugular vein and right common carotid artery, before cannula use 5 patients had been inserted central vein tube and 3 patients with blood filter tube in right internal jugular vein, in one case cannula was applied during cardiopulmonary resuscitation.V-A ECMO had been built for all the cases successfully, the median operation time was (45±26) min.The pump flow was 80-150 ml/(kg·min), the median duration of ECMO support was 153(14-567) h. Sixteen (64%) patients weaned off ECMO successfully, 15(60%) survived to hospital discharge.About the complication of cannula, six patients developed cannula site bleeding, and two patients required re-fixation of cannula, one patient's external jugular vein had been hurt and sutured for bleeding.

CONCLUSION

Application of right jugular vessels to build ECMO is easy and safe for treating the sick children. The skill should be proficient to assure ECMO run and reduce the complications.

Inhibiting GLUT-1 expression and PI3K/Akt signaling using apigenin improves the radiosensitivity of laryngeal carcinoma in vivo

Hypoxia is an important factor in radioresistance of laryngeal carcinoma. Glucose transporter-1 (GLUT-1) is an important hypoxic marker in malignant tumors, including laryngeal carcinoma. Apigenin is a natural phytoestrogen flavonoid that has potential anticancer effects. Various studies have reported that the effects of apigenin on lowering GLUT-1 expression were involved in downregulation of the PI3K/Akt pathway. Thus, apigenin may improve the radiosensitivity of laryngeal carcinoma by suppressing the expression of GLUT-1 via the PI3K/Akt pathway. The effect of GLUT-1 and PI3K/Akt pathway-related factor expressions by apigenin or antisense oligonucleotides (AS-ODNs) on the radiosensitivity of laryngeal carcinoma in vivo was assessed. The xenograft volume, xenograft weight and apoptosis detection were performed to determine radiosensitivity. The results showed that apigenin or apigenin plus GLUT-1 AS-ODNs improved the radiosensitivity of xenografts. Apigenin or apigenin plus GLUT-1 reduced the expression of GLUT-1, Akt, and PI3K mRNA after X-ray radiation. We found similar results at the protein level. The results suggest that the effects of apigenin on inhibiting xenograft growth and enhancing xenograft radiosensitivity may be associated with suppressing the expression of GLUT-1 via the PI3K/Akt pathway. In addition, apigenin may enhance the effects of GLUT-1 AS-ODNs via the same mechanism.

Follicular dendritic cell sarcoma of the right tonsil: A case report and literature review

The current study presents a case of extranodal follicular dendritic cell sarcoma (FDCS) of the tonsil and reviews the relevant literature. In the present case, a 59-year-old male presented with a globus sensation in the right pharynx for 6 weeks. On clinical examination, a painless non-ulcerated enlarged right tonsil was identified; the tonsil was covered with a normal mucus membrane. A right tonsillectomy was performed under general anesthesia. The final pathological diagnosis was follicular dendritic cell sarcoma of the right tonsil. Postoperatively, the patient received radiotherapy. The patient remains alive without disease recurrence or metastasis 44 months after tonsillectomy. To the best of our knowledge, only 42 cases of FDCS of the tonsil have been reported to date. Of the 42 cases, 41 patients underwent surgery and one patient refused treatment. A total of 23 (54.7%) received surgery alone. Adjuvant treatment was administered for 18 patients (42.9%). Six patients (14.3%) experienced local recurrences and two patients (4.8%) succumbed to the disease 24 months after treatment. The three-, five-, and eight-year overall survival rates for the entire group were 86.5, 77.8 and 77.8%, respectively. Furthermore, a tumor diameter of ≥4 cm was prognostic upon univariate analysis (χ²=4.634; P=0.031; excluding incomplete data). Tonsillar FDCS is rare and is associated with high rates of recurrence and metastasis, therefore, adjuvant treatment should be prescribed.

Role of PET/CT in the diagnosis, staging, and follow-up of a nasal-type natural killer T-cell lymphoma in the larynx: a case report and literature review

BACKGROUND

Nasal-type natural killer T-cell lymphoma involving the larynx is uncommon. Our search revealed only 12 cases reported previously in the English-language literature.

CASE REPORT

We report a case of laryngeal NKTCL. In December 2011, the patient was diagnosed with nasal-type NKTCL and FDG PET/CT showed the lesions were confined to the nasal cavity (stage I). At 1 year after radiotherapy, the patient presented with hoarseness and FDG PET/CT revealed high FDG uptake in the subglottic region and left cervical lymph nodes. A biopsy of the subglottis confirmed NKTCL (stage II). He then received chemotherapy and 14 months after the completion of chemotherapy, FDG PET/CT showed no evidence of recurrence or metastasis.

CONCLUSIONS

PET/CT has better sensitivity than other conventional methods and may play an important role in the diagnosis, staging, and follow-up of nasal-type natural killer T-cell lymphoma.

Metastatic squamous cell carcinoma of the gingiva appearing as a solitary branchial cyst carcinoma: diagnostic role of PET/CT

We herein present a case of a left cervical cystic mass, for which the initial pathological diagnosis was branchial cleft cyst carcinoma (following complete mass excision). Thorough postoperative examinations, including with FDG positron emission tomography/computed tomography (PET/CT), revealed a primary tumor in the retromolar region of the left mandible. A 52-year-old female presented with a 2-month history of a painless, progressively enlarged left-sided neck mass. Fine-needle aspiration biopsy suggested a branchial cleft cyst. Physical examination revealed a 3 × 3-cm smooth, tender mass in the upper-left neck and anterior border of the sternocleidomastoid muscle. Examination using nasendoscopy and a strobolaryngoscope revealed no abnormalities of the nasal cavity, nasopharynx, oropharynx, hypopharynx or larynx. MRI of the neck revealed a solitary, round, cystic mass under the left parotid gland. The mass was excised completely. Pathologic results indicated a branchial cleft cyst carcinoma. According to the diagnostic criteria for a branchial cleft cystic carcinoma, PET/CT was performed to detect the occult primary site. PET/CT revealed high FDG uptake in the tooth root of the left mandible. Frozen sections of the mass were indicative of moderate, differentiated squamous cell carcinoma. The carcinoma in the retromolar region of the left mandible was locally excised under general anesthesia. A partial left maxillectomy, partial mandibulectomy, and left radical neck dissection were performed. The patient received postoperative concurrent chemoradiotherapy, and was disease-free at the 8-month follow-up. True branchial cleft cyst carcinoma is rare: once diagnosed, it should be distinguished from metastatic cystic cervical lymph and occult primary carcinoma. FDG PET/CT is useful in the identification of occult primary tumor.

Postoperative radiotherapy for glioma: improved delineation of the clinical target volume using the geodesic distance calculation

OBJECTS

To introduce a new method for generating the clinical target volume (CTV) from gross tumor volume (GTV) using the geodesic distance calculation for glioma.

METHODS

One glioblastoma patient was enrolled. The GTV and natural barriers were contoured on each slice of the computer tomography (CT) simulation images. Then, a graphic processing unit based on a parallel Euclidean distance transform was used to generate the CTV considering natural barriers. Three-dimensional (3D) visualization technique was applied to show the delineation results. Speed of operation and precision were compared between this new delineation method and the traditional method.

RESULTS

In considering spatial barriers, the shortest distance from the point sheltered from these barriers equals the sum of the distance along the shortest path between the two points; this consists of several segments and evades the spatial barriers, rather than being the direct Euclidean distance between two points. The CTV was generated irregularly rather than as a spherical shape. The time required to generate the CTV was greatly reduced. Moreover, this new method improved inter- and intra-observer variability in defining the CTV.

CONCLUSIONS

Compared with the traditional CTV delineation, this new method using geodesic distance calculation not only greatly shortens the time to modify the CTV, but also has better reproducibility.

Expression of hypoxia-related markers in inflammatory myofibroblastic tumors of the head and neck

Background

The etiology of inflammatory myofibroblastic tumors (IMTs) is controversial and the prognosis is unpredictable. Previous studies have not investigated the expression of hypoxia-related markers in IMTs.

Methods

Between 2002 and 2012, 12 consecutive patients with histologically proven IMTs were enrolled in the study. Immunohistochemistry was used to detect GLUT-1, HIF-1α, PI3K, and p-Akt expression in paraffin-embedded tumor specimens. Associations among GLUT-1, HIF-1α, PI3K, and p-Akt protein expression and clinical parameters were investigated.

Results

The mean duration of follow-up was 52.1 months (range, 11 to 132 months). Six patients had local recurrence. GLUT-1, HIF-1α, PI3K, and p-Akt expression were detected in 41.7%, 50.0%, 33.3%, and 41.7% of patients, respectively. Fisher’s exact test revealed significant correlations between recurrence of IMT and PI3K expression (P = 0.01) and p-Akt expression (P = 0.015). Univariate analyses revealed significant correlations between survival and GLUT-1 expression (P = 0.028), PI3K expression (P = 0.006), and p-Akt expression (P = 0.028). Multivariate analysis did not show a significant relationship between survival and GLUT-1, HIF-1α, PI3K, or p-Akt. Spearman rank correlation analysis showed significant correlations between HIF-1α and PI3K expression (r = 0.707, P = 0.01) and between p-Akt and PI3K expression (r = 0.837, P = 0.001).

Conclusions

Although our results are inconclusive owing to the small sample size, they suggest that PI3K and p-Akt expression may play a role in the recurrence of IMTs of the head and neck.

Effect of antisense oligodeoxynucleotides glucose transporter-1 on enhancement of radiosensitivity of laryngeal carcinoma

PURPOSE

Laryngeal carcinomas always resist to radiotherapy. Hypoxia is an important factor in radioresistance of laryngeal carcinoma. Glucose transporter-1 (GLUT-1) is considered to be a possible intrinsic marker of hypoxia in malignant tumors. We speculated that the inhibition of GLUT-1 expression might improve the radiosensitivity of laryngeal carcinoma.

METHODS

We assessed the effect of GLUT-1 expression on radioresistance of laryngeal carcinoma and the effect of GLUT-1 expressions by antisense oligodeoxynucleotides (AS-ODNs) on the radiosensitivity of laryngeal carcinoma in vitro and in vivo.

RESULTS

After transfection of GLUT-1 AS-ODNs: MTS assay showed the survival rates of radiation groups were reduced with the prolongation of culture time (p<0.05); Cell survival rates were significantly reduced along with the increasing of radiation dose (p<0.05). There was significant difference in the expression of GLUT-1mRNA and protein in the same X-ray dose between before and after X-ray radiation (p<0.05). In vivo, the expressions of GLUT-1 mRNA and protein after 8Gy radiation plus transfection of GLUT-1 AS-ODNs were significant decreased compared to 8Gy radiation alone (p<0.001).

CONCLUSION

Radioresistance of laryngeal carcinoma may be associated with increased expression of GLUT-1 mRNA and protein. GLUT-1 AS-ODNs may enhance the radiosensitivity of laryngeal carcinoma mainly by inhibiting the expression of GLUT-1.

¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography as an effective diagnostic workup in cervical metastasis of carcinoma from an unknown primary tumor

PURPOSE

The purpose of this study is to assess the potential of ¹⁸F-fluorodeoxyglucose (¹⁸FDG) positron emission tomography/computed tomography (PET/CT) imaging for the diagnosis of cervical metastasis of carcinoma of an unknown primary tumor (CUP) and to determine whether the maximum standardized uptake value (SUV(max)) is a prognostic factor.

METHODS

Twenty-five consecutive patients with cervical metastasis of CUP were retrospectively analyzed by PET/CT between July 2007 and July 2011.

RESULTS

FDG PET/CT suggested a primary tumor in 21 out of 25 patients (84.0%). The sensitivity of FDG PET/CT in detecting the primary tumor was 73.3% (11 of 15), and the positive predictive value was 52.4% (11 of 21). The median follow-up duration of survival patients was 10.4 months (range: 0-30 months). The estimated 2-year overall survival rate of all patients was 50.0%. Univariate analyses did not reveal a significant difference in overall survival between the group of 11 patients identified by pathology and the 14 patients not identified by pathology (overall survival was 57.1% and 49.1%, respectively; p=0.468). The median SUV(max) was 7.6. In the log-rank test, patients with a low SUV(max) (≤ 7.0) in cervical lymph nodes had a significantly higher survival rate at 2 years (87.5% vs. 21.2%; p=0.007) than patients with a high SUV(max) (>7.0).

CONCLUSIONS

Although our study was inconclusive due to the small sample size, our results suggest that FDG PET/CT may be an effective diagnostic workup in the cervical metastasis of carcinoma from an unknown primary tumor (UPT). In the present study, SUV(max) of PET/CT in the cervical lymph node may serve as a prognostic factor of cervical metastasis of carcinoma from a UPT based on the limited number of patients. Further studies are needed to confirm these findings.

Functional up-regulation of P2X3 receptors in dorsal root ganglion in a rat model of bone cancer pain

BACKGROUND

Cancer-induced bone pain remains a clinical challenge due to the poor understanding of the mechanisms. Recent study revealed extracellular adenosine triphosphate (ATP) and P2X receptors may be implicated in nociceptive signalling under cancer pain state. Therefore, here we investigated the potential role of P2X(3) receptor in a rat model of bone cancer pain.

METHODS

Walker 256 tumour cells were inoculated into the left tibia of Wistar rats. The model was verified by X-ray imaging, pathology and behaviour examinations. The expression of P2X(3) receptors in dorsal root ganglia (DRG) was examined. Functional significance of altered P2X(3) receptors was investigated by measuring influx upon α,β-meATP stimulation in acutely dissociated DRG neurons. Moreover, A-317491, an antagonist of P2X(3) receptors, was administrated intrathecally or locally to evaluate its analgesia effect in the cancer pain animals.

RESULTS

The P2X(3) receptor was up-regulated for about 50% in DRG neurons in rats with bone cancer at both protein and mRNA levels and correlated with the pain behaviour in bone cancer rats. A 51.9% increase of α,β-me ATP (10 μM, for 4 s) evoked transient response currents and a higher percentage of neurons responsive to the application of α,β-me ATP was detected in bone cancer rats. Intrathecal or local injection of A-317491 significantly attenuated pain behaviour induced by bone cancer.

CONCLUSIONS

These results suggest that the P2X(3) receptor is functionally up-regulated in DRG in cancer rats. P2X(3) receptor is a promising target for therapeutic intervention in cancer patients for pain management.

The efficacy and safety of vildagliptin in patients with type 2 diabetes: a meta-analysis of randomized clinical trials

WHAT IS KNOWN AND OBJECTIVE

Dipeptidyl peptidase-4 (DPP-4) inhibitors are a relatively new class of drugs for the management of type 2 diabetes (T2DM). Vildagliptin is an oral DPP-4 inhibitor approved in more than 70 countries. The purpose of this meta-analysis is to provide an update on the clinical efficacy and safety of vildagliptin in patients with T2DM.

METHODS

A literature search identified 30 randomized controlled trials comparing vildagliptin with comparators (placebo or other hypoglycaemic agents). Meta-analyses were conducted for HbA1c, weight, fasting plasma glucose (FPG), hypoglycaemia and other adverse events. The outcomes of HbA1c, weight and FPG were analysed as weighted mean differences (WMD), and the number of ADRs events as relative risks (RR).

RESULTS

Compared with placebo, vildagliptin lowered HbA1c {WMD, -0·77% [95% confidence interval (CI), -0·96% to -0·58%] for 100 mg/day of vildagliptin and -0·58% [95% CI, -0·72% to -0·44%] for 50 mg/day of vildagliptin}. The effect was non-inferior to thiazolidinediones, sulfonylureas and α-glycosidase inhibitors, but inferior to metformin. Compared with placebo, treatment with 50 mg/day of vildagliptin caused neutral weight changes, while 100 mg/day of vildagliptin resulted in slight weight gain [0·95 kg (95% CI, 0·73-1·17 kg)]. In addition, compared to comparators, vildagliptin was not associated with an increase in overall risk for any adverse events [RR, 0·97 (95% CI, 0·94-0·99)]. The incidence of hypoglycaemia was low with vildagliptin, and the risk with vildagliptin was not significantly different from the comparators [0·85 (95% CI, 0·49-1·47)]. The use of vildagliptin did not display any increased risks of infection [1·03 (95% CI, 0·94-1·13) for nasopharyngitis and 1·07 (95% CI, 0·90-1·27) for upper respiratory tract infection].

WHAT IS NEW AND CONCLUSION

Vildagliptin is effective in glycaemic control with a low risk of hypoglycaemia and other adverse reactions. This may have an important impact on patient adherence to this medication.

Effect of the route of foot-and-mouth disease virus infection of piglets on the course of disease

Three different routes of Foot-and-mouth disease virus (FMDV) infection of piglets, namely intranasal (i.n.) through drops, intradermal (i.d.) into the foot, and intramuscular (i.m.) were compared regarding the onset and severity of the disease. The results showed that the i.d. injection of the virus resulted in the fastest onset of the disease. The i.m. injection led to a delayed onset, but the final effect was identical with i.d. injection. Moreover, the i.m. injection was simpler to perform and easier to evaluate. Therefore, the i.m. injection of piglets is recommended as the optimal infection route for evaluation of the FMDV vaccine potency.

A comparison of liver function after hepatectomy with inflow occlusion between sevoflurane and propofol anesthesia

BACKGROUND

In this study, we compared liver function tests after hepatectomy with inflow occlusion as a function of propofol versus sevoflurane anesthesia.

METHODS

One hundred patients undergoing elective liver resection with inflow occlusion were randomized into a sevoflurane group or a propofol group. General anesthesia was induced with 3 μg/kg fentanyl, 0.2 mg/kg cisatracurium, and target-controlled infusion of propofol, set at a plasma target concentration of 4 to 6 μg/mL, or sevoflurane initially started at 8%. Anesthesia was maintained with target-controlled infusion of propofol (2-4 μg/mL) or sevoflurane (1.5%-2.5%). The primary end point was postoperative liver injury assessed by peak values of liver transaminases.

RESULTS

Transaminase levels peaked between the first and the third postoperative day. Peak alanine aminotransferase was 504 and 571 U/L in the sevoflurane group and the propofol group, respectively. Peak aspartate aminotransferase was 435 U/L after sevoflurane and 581 U/L in the propofol group. There were no significant differences in peak alanine aminotransferase or peak aspartate aminotransferase between groups. Other liver function tests including bilirubin and alkaline phosphatase, and peak values of white blood cell counts and creatinine, were also not different between groups.

CONCLUSIONS

Sevoflurane and propofol anesthetics resulted in similar patterns of liver function tests after hepatectomy with inflow occlusion. These data suggest that the 2 anesthetics are equivalent in this clinical context.

The effects of obstructive jaundice on the pharmacodynamics of propofol: does the sensitivity of intravenous anesthetics change among icteric patients?

BACKGROUND

Some studies suggest that certain clinical symptoms of cholestasis, such as fatigue and pruritus, result from altered neurotransmission. Patients with obstructive jaundice also have labile blood pressure and heart rate. In the present study, the authors investigated whether obstructive jaundice affects a patient's sensitivity to hypnotics and the haemodynamic profile of propofol.

METHODS

Thirty-six ASA physical status I/II/III patients with serum total bilirubin (TBL) from 7.8 to 362.7 micromol/l scheduled for bile duct surgery were recruited. A computer-controlled propofol infusion programmed for effect site target was used to rapidly attain and maintain sequential increase of the compartment concentration (from 1 to 3 microg/ml). Each target-controlled concentration was maintained for about 12 min, and arterial blood samples were drawn for propofol concentration determination. The bispectral index (BIS) and mean arterial pressures (MAP) were used as indices of the propofol effect. The relation between the concentration and the effects was described by the Hill equation. The pharmacodynamic parameters were optimized using a nonlinear mixed-effect model.

RESULTS

TBL was not a significant covariate of EC(50) for the pharmacodynamic model. For BIS and MAP, the parameters of the pharmacodynamic model were E(max)=75.77%, EC(50)=2.34 microg/ml, and gamma=1.82, and E(max)=47.83%, EC(50)=1.49 microg/ml, and gamma=1.88, respectively.

CONCLUSIONS

We demonstrated that obstructive jaundice with serum TBL from 7.8 to 362.7 micromol/l had no effect on propofol pharmacodynamics observed by BIS and MAP.

Reliability and validity of a patient self-administered daily questionnaire to assess impact of oral mucositis (OM) on pain and daily functioning in patients undergoing autologous hematopoietic stem cell transplantation (HSCT)

Oral mucositis (OM) is a frequent complication of myeloablative therapy and HSCT. We evaluated the feasibility, reliability, and validity of a new patient self-reported daily questionnaire on OM and its impact on daily functions. This OM Daily Questionnaire (OMDQ), containing 10 items, was developed for use in palifermin clinical trials. In a phase 3 study, 212 patients received palifermin or placebo for three consecutive days before conditioning and three consecutive days after HSCT. Compliance rates were consistently >80% for most patients. Mouth and throat soreness (MTS) and MTS-Activity Limitations (MTS-AL) (swallowing, drinking, eating, talking, and sleeping) scores on consecutive days were highly correlated (days 7,8 = 0.70-0.86; test-retest reliability). Correlations among items measuring the same construct ranged between 0.5 and 0.8 (internal consistency reliability). The WHO Oral Toxicity scale was the clinical comparator to assess the criterion, discriminative, and evaluative validities of MTS-related questions. Most correlation coefficients between the WHO and MTS ranged between 0.45 and 0.55. Patients with more severe WHO OM grades had higher MTS mean scores. Changes in MTS scores were similar, but patients detected changes 1-3 days earlier than clinicians. In conclusion, the OMDQ is a feasible, reliable, valid, and responsive patient-reported measure of OM severity.

Observation of a near-threshold enhancement in the pp mass spectrum from radiative J/psi-->gammapp decays

We observe a narrow enhancement near 2m(p) in the invariant mass spectrum of pp pairs from radiative J/psi-->gammapp decays. No similar structure is seen in J/psi-->pi(0)pp decays. The results are based on an analysis of a 58 x 10(6) event sample of J/psi decays accumulated with the BESII detector at the Beijing electron-positron collider. The enhancement can be fit with either an S- or P-wave Breit-Wigner resonance function. In the case of the S-wave fit, the peak mass is below 2m(p) at M=1859(+3)(-10) (stat)+5-25(syst) MeV/c(2) and the total width is Gamma<30 MeV/c(2) at the 90% confidence level. These mass and width values are not consistent with the properties of any known particle.

Measurements of the cross section for e(+)e(-) --> hadrons at center-of-mass energies from 2 to 5 GeV

We report values of R = sigma(e(+)e(-)-->hadrons)/sigma(e(+)e(-)-->mu(+)mu(-)) for 85 center-of-mass energies between 2 and 5 GeV measured with the upgraded Beijing Spectrometer at the Beijing Electron-Positron Collider.

Disruption of cytoskeletal integrity impairs Gi-mediated signaling due to displacement of Gi proteins

beta1 integrins play a crucial role as cytoskeletal anchorage proteins. In this study, the coupling of the cytoskeleton and intracellular signaling pathways was investigated in beta1 integrin deficient (-/-) embryonic stem cells. Muscarinic inhibition of the L-type Ca2+ current (ICa) and activation of the acetylcholine-activated K+ current (IK,ACh) was found to be absent in beta1 integrin-/- cardiomyocytes. Conversely, beta adrenoceptor-mediated modulation of ICa was unaffected by the absence of beta1 integrins. This defect in muscarinic signaling was due to defective G protein coupling. This was supported by deconvolution microscopy, which demonstrated that Gi exhibited an atypical subcellular distribution in the beta1 integrin-/- cardiomyocytes. A critical role of the cytoskeleton was further demonstrated using cytochalasin D, which displaced Gi and impaired muscarinic signaling. We conclude that cytoskeletal integrity is required for correct localization and function of Gi-associated signaling microdomains.

[Neocartilage formation in vitro using transduced mesenchymal stem cells cultured on biomimetic biodegradable polymer scaffolds]

OBJECTIVE

To investigate the effect of transforming growth factor (TGF) beta 1 gene transfection on the growth of mesenchymal stem cells(MSCs) and to evaluate a new biomimetic biodegradable polymer as scaffolds for applications in articular cartilage tissue engineering.

METHODS

Principles of tissue engineering were combined organically with principles of gene therapy to produce cultured periosteum-derived MSCs transduced with the full-length rat TGF-beta 1 cDNA in vitro. These cells were then seeded onto three-dimensional porous poly-DL-lactide scaffolds modified with poly-L-lysine that mimicked cell-binding domains found on natural extracellular matrix to promote specific cell adhesion. The adhesion, proliferation, and differentiation of the transfected MSCs were examined with scanning electron microscope within 2 weeks.

RESULTS

All cells adhered to the biomimetic matrices well, but more cartilage-like tissue was formed for TGF-beta 1 gene modified MSCs/scaffolds composites than for the control groups. Transfer of gene encoding TGF-beta 1 to MSCs promoted its proliferation and differentiation significantly.

CONCLUSIONS

The TGF-beta 1 gene transduced MSCs/biomimetic matrix composites used in this study was the first attempt to apply the principles of molecular tissue engineering for articular cartilage repair. This new molecular tissue engineering approach could be of potential benefit to repair damaged articular cartilage, especially in osteoarthritis. The new biomimetic biodegradable polymer matrices modified with biomolecules not only have good structural compatibility, but also have better interfacial compatibility and bioactivity, and can be used as scaffolds for articular cartilage tissue engineering.

Effectiveness of breast self-examination nursing interventions for Taiwanese community target groups

BACKGROUND

Because of the increasing morbidity and mortality from breast cancer, the Health Department in Taiwan in 1992 has identified early detection of breast cancer as one of the national health objectives. The effectiveness of Breast Self-Examination (BSE) in detecting breast cancer depends not only on frequency, but also on accuracy. This study explored the effects of nursing intervention on the BSE intention, BSE frequency and BSE accuracy among beauticians as community target groups.

DESIGN

This study was comprised of two stages. In the first stage, 198 beauticians in Taipei County were surveyed. Those women with perceived barrier scores > or =15 points in the first stage were selected for the second stage with the quasi-experimental design. The experimental group was provided with BSE instruction for the enhancement of BSE competence, personalized strategies to reduce barriers to BSE and monthly telephone reminders after BSE instruction class for 3 months. The study instruments were Champion's BSE questionnaire, Lashley's 15 BSE steps and BSE items of social norm referenced Lierman et al.

RESULTS

The mean age of the 198 beauticians was 28 (+/-8.6), the mean year of education was 10 (+/-2.4) and 60% of participants were married. The results of the study indicate that the program significantly increased BSE frequency, BSE accuracy, perceived benefit of BSE, perceived competence in BSE and decreased perceived susceptibility to breast cancer and perceived barriers to practice BSE. Multiple regression analysis indicated that the perceived competency, susceptibility and social normative influence accounted for 25% of the variance in BSE intention. Perceived competency and social normative influence accounted for 15% of the variance in BSE frequency, while intention, social normative influence and perceived competency accounted for 21% of the variance in BSE accuracy.

The relationship between menstrual attitudes and menstrual symptoms among Taiwanese women

AIM OF THE STUDY

This study explored characteristics of the menstrual cycle including duration, prevalence and severity of symptoms and examined the relationship of these characteristics with attitudes toward menstruation.

BACKGROUND

Conceptualization of menstrual phenomena and attitudes toward menstruation may vary among cultures. While data about menstrual health among American women are widely available, there are little data concerning menstrual health in Taiwanese women.

DESIGN/METHODS

A total of 30 healthy women with a mean age of 24.4 years participated in the study and made daily records of symptoms over a 90-day period with the Woods Daily Health Diary (WDHD). They then retrospectively completed the Moos Menstrual Distress Questionnaire (MMDQ) and the Menstrual Attitudes Questionnaire (MAQ).

RESULTS

The mean age of menarche of these women was 13 years, their mean cycle duration was 5.8 days and the cycle length was 31.1 days. The mean scores of five subscales for MAQ ranged from 2.19 to 3.28. Forty-six percent of the surveyed Taiwanese women agreed that the onset of menstruation can be predicted and anticipated, and 78% of these women agreed that menstruation was a natural event.

CONCLUSIONS

Menstrual attitudes in Taiwanese women are multidimensional, and that significant cross-cultural differences are present. Attitudes toward menstruation in Taiwanese women are related to their physical, cognitive, behavioural and psychological changes in the premenstrual and menstrual phases.

Outwards currents in embryonic stem cell-derived cardiomyocytes

The aim of the present study was to investigate the expression and functional role of outwards currents during the early stages of cardiomyogenesis. The predominant repolarizing current in early-stage, embryonic stem (ES) cell-derived cardiomyocytes was a 4-aminopyridine (4-AP) sensitive [concentration for half-maximal inhibition (IC50) 1.7 mM], transient outward current (Ito) with a current density of 10.3+/-2.1 pA/pF (n=72). We observed two additional, rapidly activating, outwardly rectifying current components, I(K),sus and Ires, in early- and late-stage cardiomyocytes. These currents were characterized by slow and no inactivation, respectively, during the depolarizing voltage step. I(K),sus was detected in about 25% of cells investigated and displayed 4-AP hypersensitivity (IC50 29 microM), whereas Ires was found in all cells of both differentiation stages and was 4-AP insensitive. In contrast to early-stage cells, Ires formed the larger portion of the aggregate, whole-cell current in late-stage, ES cell-derived cardiomyocytes. The current densities of all three current components increased during development, however, the most prominent increase was observed for I(res) from 3.6+/-0.8 pA/pF (n=72) to 8+/-1.1 pA/pF (n=35). In current-clamp recordings in early-stage, spontaneously contracting cardiomyocytes, 4-AP depolarized the cells, lengthened the action potential duration (APD) and increased the action potential frequency. In late-stage cells 4-AP had no effect on action potential frequency. We conclude that in early-stage cardiomyocytes I(to) plays an important role in controlling electrical activity.

Functional expression and regulation of the hyperpolarization activated non-selective cation current in embryonic stem cell-derived cardiomyocytes

1. The biophysical and pharmacological characteristics of the hyperpolarization activated non- selective cation current (If) were recorded using whole-cell voltage clamp in embryonic stem (ES) cell-derived cardiomyocytes at different stages of development. 2. The cation current was detected in a large percentage (65 %) of early stage (EDS, differentiated for 7 + 3-4 days) cells at a current density of 11.4 +/- 0.6 pA pF-1 (n = 47). In late stage (LDS, differentiated for 7 + 9-12 days) cells the percentage of cells expressing If decreased (45 %), but If densities (15.5 +/- 0.9 pA pF-1, n = 20) were increased. 3. The muscarinic agonist carbachol (CCh, 1 microM) depressed basal If in EDS cells by 45.7 +/- 6.5 %, n = 5) and was without effect in LDS cardiomyocytes (n = 4). The beta-adrenoceptor agonist isoprenaline (ISO, 1 microM) stimulated If in LDS cells by 33 +/- 5.2 % (n = 6) but not in EDS cells (n = 5). 4. Cell infusion with the catalytic subunit of the cAMP-dependent protein kinase (PKA, 7 microM) stimulated If in EDS cells by 37.0 +/- 2.9 %, (n = 4), but subsequent superfusion of 8-bromo-cAMP (200 microM) was without effect. Intracellular perfusion of LDS cardiomyocytes with the highly selective peptide inhibitor of PKA (PKI, 20 microM) completely inhibited the stimulation of the L-type Ca2+ current (ICa,L) as well as of If by ISO (1 microM). 5. Extracellular superfusion with phosphodiesterase (PDE) inhibitors - IBMX, a non-selective antagonist, Erythro-9-(2-hydoxy-3-nonyl)adenine (EHNA), a PDE2 antagonist and rolipram, a PDE4 antagonist - resulted in stimulation of ICa,L and If in EDS cells. By contrast, milrinone and cilostamide, two PDE3 antagonists, stimulated ICa,L, but not If. 6. The present work demonstrates that If is functionally expressed during early cardiomyogenesis. Similar to ICa,L, If is regulated during embryonic development by phosphorylation via PKA. In contrast to ICa,L, If is not regulated by PDE3 suggesting different localization of these ion channels with respect to PDE3.

Identification of a highly diverged class of S-adenosylmethionine synthetases in the archaea

S-adenosylmethionine is the primary alkylating agent in all known organisms. ATP:L-methionine S-adenosyltransferase (MAT) catalyzes the only known biosynthetic route to this central metabolite. Although the amino acid sequence of MAT is strongly conserved among bacteria and eukarya, no homologs have been recognized in the completed genome sequences of any archaea. In this study, MAT has been purified to homogeneity from the archaeon Methanococcus jannaschii, and the gene encoding it has been identified by mass spectrometry. The peptide mass map identifies the gene encoding MAT as MJ1208, a hypothetical open reading frame. The gene was cloned in Escherichia coli, and expressed enzyme has been purified and characterized. This protein has only 22 and 23% sequence identity to the E. coli and human enzymes, respectively, whereas those are 59% identical to each other. The few identical residues include the majority of those constituting the polar active site residues. Each complete archaeal genome sequence contains a homolog of this archaeal-type MAT. Surprisingly, three bacterial genomes encode both the archaeal and eukaryal/bacterial types of MAT. This identification of a second major class of MAT emphasizes the long evolutionary history of the archaeal lineage and the structural diversity found even in crucial metabolic enzymes.

Empirical criteria for the selection of quality-of-life instruments for the evaluation of peripheral blood progenitor cell transplantation

We propose a method for selecting quality-of-life instruments for use in phase III trials using the convergent validity of patient responses collected in phase I and II clinical trials. Two generic and two disease-specific instruments were administered to patients with breast cancer undergoing peripheral blood progenitor cell mobilization and transplantation. They included the visual analog scale from the EuroQoL EQ5D instrument, the SF-36, the European Organization for Research and Treatment of Cancer (EORTC)-QLQ-C30, and the Functional Assessment of Cancer Therapy instrument. No single instrument was found to have superior convergent validity in all domains, but the EORTC-QLQ-C30 seemed to perform better than the SF-36.

Social support and breast self-examination

Declining practice of breast self-examination (BSE) among women over the age of 55 years dramatically decreases the probability of early detection of breast cancer. About two-thirds of women who die of breast cancer are over the age of 55 years. Social support has been found to be associated with health behaviors. Although a woman's health may benefit from supportive relationships, the effect of diminished social networks on practices of BSE among older women has not been examined. Thus, the purpose of this study was to determine the relationship between social support and the frequency and accuracy of BSE practice. The sample consisted of 22 women, 55 years of age and older, who were having routine examinations at a small Midwestern gynecologic clinic. Social support was assessed by the Norbeck Social Support Questionnaire, and two tools assessed the accuracy and frequency of BSE. Social support was found to be significantly related to the frequency of BSE (r = 0.45, p < 0.05), but not to the accuracy of BSE (r = 0.28). The results also indicated that these women had lower social support scores compared with younger women. Planners of nursing intervention for BSE should consider health care providers as important resources in social support networks for the reinforcement of frequency and accuracy of BSE for older women.

Variables associated with breast self-examination among Chinese women

Asians are the fastest growing minorities in the U.S. To deliver culturally sensitive care is a significant challenge to the nursing profession. Research identifying variables associated with breast self-examination (BSE) in the U.S. has been conducted on Caucasian women, but little is known about Asian women. Based on the health belief model (HBM) and Bandura's social learning theory, the purpose of this study was to identify barriers to the practice of BSE among Chinese women. The Chinese women (n = 174; mean age, 31 years) were surveyed with a 38-item, five-point Likert scale developed by Champion, and Lauver and Angerame, as well as a six-step accuracy check. The factors included susceptibility; seriousness for breast cancer; general efficacy for BSE; specific efficacy of BSE for oneself; competence; comfort; and control. The results showed that only 15% of these Chinese women practiced BSE monthly, and 48% reported never having performed BSE. Approximately 50% had no opinion on perceived susceptibility to and seriousness of breast cancer; nevertheless, > 80% recognize the efficacy of BSE. Perceived competence significantly accounted for 10% of the variance on BSE frequency (p < 0.001). Implications for nursing interventions that foster competence in BSE for this population are suggested. The study also demonstrates culturally specific methodological considerations.

ESR dating of tooth enamel: comparison with U-series, FT and TL dating at the Peking man site

Deer tooth samples from Zhoukoudian, the Peking Man Cave, were studied. Non-linear fitting is used to determine AD, from which ESR ages were calculated by both the disequilibria model (DU) and linear uptake model (LU). Comparison of ESR ages with those from U-series, FT and TL methods show that the enamel of deer teeth is a suitable material for ESR dating.

Regulation of the GTPase activity of the ras-like protein p25rab3A. Evidence for a rab3A-specific GAP

The rab3A gene product is a 25-kilodalton guanine nucleotide-binding protein, expressed at high levels in neural tissue, which has about 30% homology to ras. Recombinant rab3A protein and p25rab3A purified from bovine brain membranes have been used as substrates to look for factors that regulate its biochemical activity. A detergent-soluble factor associated with rat brain membranes exists that accelerates the GTPase activity of both mammalian and recombinant p25rab3A. The activity was thermolabile, sensitive to trypsin, and behaved like an integral membrane protein. GTPase-activating protein (GAP) activity toward p25rab3A was also detected in the cytosolic fraction. This activity was observed in all other tissues examined, in addition to brain. Based upon dose-response data, the rab3A-GAP activity from rat brain was approximately equally distributed between cytosolic and membrane fractions; no activity was found in the nuclear fraction. Recombinant ras-specific GAP had no effect upon the GTPase activity of p25rab3A. By gel filtration chromatography, the factor in rat brain cytosol has a molecular size of 400,000 daltons.

Acute experimental allergic encephalomyelitis in SJL/J mice induced by a synthetic peptide of myelin proteolipid protein

Clinical, histologic, and ultrastructural characteristics of acute experimental allergic encephalomyelitis (EAE) induced by sensitization with a synthetic peptide corresponding to mouse myelin proteolipid protein (PLP) residues 139-151 HCLGKWLGHPDKF were studied in SJL/J mice. Groups of mice were immunized with 20, 50, or 100 nmol of the peptide and were killed from seven to 28 days after sensitization or when they were moribund. Beginning on Day 9, the mice showed signs of EAE and the disease progressed rapidly to paralysis. Central nervous system (CNS) inflammation, edema, gliosis, and demyelination were found in all mice killed between Days 10 and 28 and white matter lesion areas correlated with clinical score at the time the mice were killed. Peripheral nerve roots and the cauda equina did not have lesions. Within the range studied, the severity of clinical or histologic disease was the same regardless of the PLP peptide dose. Two of ten mice immunized with 100 nmol and none of 14 mice given smaller doses of a synthetic peptide of mouse myelin basic protein (MBP) showed clinical EAE. These mice had small numbers of CNS lesions that were indistinguishable from those in PLP peptide-sensitized mice. These findings demonstrate that immunization of SJL/J mice with PLP peptide 139-151 produces a disease with the clinical and morphologic features of CNS tissue-, whole PLP-, whole MBP-, and MBP peptide-induced acute EAE. Thus, PLP is a major encephalitogen and immune reactions to epitopes of different myelin proteins may induce identical patterns of injury in the CNS.