An integrated analysis of the anticarcinogenic role of forkhead box protein 1 in oesophageal squamous cell carcinoma

Forkhead box protein 1 (FOXP1) serves as a tumour promoter or suppressor depending on different cancers, but its effect in oesophageal squamous cell carcinoma has not been fully elucidated. This study investigated the role of FOXP1 in oesophageal squamous cell carcinoma through bioinformatics analysis and experimental verification. We determined through public databases that FOXP1 expresses low in oesophageal squamous cell carcinoma compared with normal tissues, while high expression of FOXP1 indicates a better prognosis. We identified potential target genes regulated by FOXP1, and explored the potential biological processes and signalling pathways involved in FOXP1 in oesophageal squamous cell carcinoma through GO and KEGG enrichment, gene co-expression analysis, and protein interaction network construction. We also analysed the correlation between FOXP1 and tumour immune infiltration levels. We further validated the inhibitory effect of FOXP1 on the proliferation of oesophageal squamous cell carcinoma cells through CCK-8, colony formation and subcutaneous tumour formation assays. This study revealed the anticarcinogenic effect of FOXP1 in oesophageal squamous cell carcinoma, which may serve as a novel biological target for the treatment of tumour.

PI3Kα inhibitor GNE-493 triggers antitumor immunity in murine lung cancer by inducing immunogenic cell death and activating T cells

Phosphatidylinositol 3-kinase (PI3K) is frequently hyperactivated in cancer, playing pivotal roles in the pathophysiology of both malignant and immune cells. The impact of PI3K inhibitors on the tumor microenvironment (TME) within lung cancer remains largely unknown. In this study, we explored the regulatory effects of GNE-493, an innovative dual inhibitor of PI3K and mammalian target of rapamycin (mTOR), on the TME of lung cancer. First, through the analysis of The Cancer Genome Atlas-lung squamous cell carcinoma (LUSC) cohort, we found PIK3CA to be related to CD8 T cells, which may affect the overall survival rate of patients by affecting CD8 function. We herein demonstrated that GNE-493 can significantly inhibit tumor cell proliferation and promote cell apoptosis while increasing the expression of the immunogenic death-related molecules CRT and HSP70 using in vitro cell proliferation and apoptosis experiments on the murine KP lung cancer cell line and human A549 lung cancer cell line. Next, through the establishment of an orthotopic tumor model in vivo, it was found that after GNE-493 intervention, the infiltration of CD4+ and CD8+ T cells in mouse lung tumor was significantly increased, and the expression of CRT in tumors could be induced to increase. To explore the mechanisms underlying PI3K inhibition-induced changes in the TME, the gene expression differences of T cells in the control group versus GNE-493-treated KP tumors were analyzed by RNA-seq, and the main effector pathway of anti-tumor immunity was identified. The IFN/TNF family molecules were significantly upregulated after GNE-493 treatment. In summary, our findings indicate that GNE-493 promotes immunogenic cell death in lung cancer cells, and elucidates its regulatory impact on molecules associated with the adaptive immune response. Our study provides novel insights into how PI3K/mTOR inhibitors exert their activity by modulating the tumor-immune interaction.

Onvansertib inhibits the proliferation and improves the cisplatin-resistance of lung adenocarcinoma via β-catenin/c-Myc signaling pathway

Polo-like kinase 1 (PLK1) is a key regulator of cell division, and its abnormal expression is related to the progression and prognosis of cancers. However, the effect of PLK1 inhibitor onvansertib on the growth of lung adenocarcinoma (LUAD) has not been explored. In this study, we performed a series of bioinformatics and experimental analyses to comprehensively investigate the role of PLK1 in LUAD. We used CCK-8 assay and colony formation assay to evaluate the growth inhibitory ability of onvansertib. Furthermore, flow cytometry was applied to exploit the effects of onvansertib on cell cycle, apoptosis, and mitochondrial membrane potential. Moreover, the therapeutic potential of onvansertib was assessed in vivo by using xenograft tumor and patient-derived xenograft (PDX) models. We found that onvansertib significantly induced the apoptosis and inhibited the proliferation and migration of LUAD cells. Mechanistically, onvansertib arrested the cells at G2/M phase and enhanced the levels of reactive oxidative species in LUAD. Accordingly, onvansertib regulated the expression of glycolysis-related genes and improved the cisplatin resistance in LUAD. Notably, the protein levels of β-catenin and c-Myc were affected by onvansertib. Taken together, our findings provide insight into the function of onvansertib and shed light on the potential clinical application of onvansertib for the treatment of patients with LUAD.

Chinese never smokers with adenocarcinoma of the lung are younger and have fewer lymph node metastases than smokers

Background

Lung cancers arising in never smokers have been suggested to be substantially different from lung cancers in smokers at an epidemiological, genetic and molecular level. Focusing on non-small cell lung cancer (NSCLC), we characterized lung cancer patients in China looking for demographic and clinical differences between the smoking and never-smoking subgroups.

Methods

In total, 891 patients with NSCLC, including 841 with adenocarcinoma and 50 with squamous cell carcinoma, were recruited in this study. Association of smoking status with demographic and clinical features of NSCLC was determined, and risk factors for lymph node metastasis and TNM stage were evaluated using Multivariate logistic regression analysis.

Results

In patients with adenocarcinoma, never smokers showed a younger age at diagnosis (54.2 ± 12.7vs. 59.3 ± 9.4, p^adjusted<0.001), a lower risk for lymph node metastasis than smokers (7,6% vs. 19.5%, p^adjusted<0.001) and less severe disease as indicated by lower percentages of patients with TNM stage of III or IV (5.5% vs. 14.7%, p^adjusted<0.001 ). By contrast, these associations were not observed in 50 patients with squamous cell carcinoma. Multivariate logistic regression analysis showed that smoking status was a risk factor for lymph node metastasis (OR = 2.70, 95% CI: 1.39–5.31, p = 0.004) but not for TNM stage (OR = 1.18, 95% CI: 0.09–14.43, p = 0.896) in adenocarcinoma.

Conclusion

This study demonstrates that lung adenocarcinoma in never smokers significantly differ from those in smokers regarding both age at diagnosis and risk of lymph node metastasis, supporting the notion that they are distinct entries with different etiology and pathogenesis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02199-z.

LINC01140 promotes the progression and tumor immune escape in lung cancer by sponging multiple microRNAs

BACKGROUND

Long intergenic non-protein coding RNA 1140 (LINC01140), a long non-coding RNA, is highly expressed in various cancers; however, its biological functions in lung cancer (LC) progression and immune escape are still unclear.

METHODS

Here, to elucidate LINC01140 function, 79 paired LC and paracancerous tissues were collected. LINC01140 expression levels were determined using fluorescence in situ hybridization and qPCR analysis. Cell counting kit-8 (CCK-8) assay and transwell assays were performed. The interaction between microRNAs (miRNAs) and LINC01140 was confirmed using an RNA immunoprecipitation assay. Cytokine-induced killer (CIK) cell phenotypes were analyzed by flow cytometry. Cytokine secretion levels were determined by ELISA. CIK cytotoxicity was assessed by measuring lactate dehydrogenase release. Besides, xenograft tumor mouse models were used to unveil the in vivo function of LINC01140.

RESULTS

We found that LINC01140 was highly expressed in human LC tissues and cell lines. High LINC01140 levels were associated with poor survival in patients with LC. LINC01140 upregulation promoted the proliferation, migration, and invasion of LC cells through direct interaction with miR-33a-5p and miR-33b-5p, thereby contributing to c-Myc expression and also inhibited cisplatin-induced cell apoptosis. In subcutaneous tumor xenograft mice, LINC01140 knockdown markedly reduced tumor growth and lung metastasis. Additionally, LINC01140 directly repressed miR-377-3 p and miR-155-5 p expression levels, resulting in the upregulation of their common downstream target programmed death-ligand 1 (PD-L1), a crucial target in LC immunotherapy. Notably, we proved that LINC01140 knockdown, along with CIK administration, suppressed the growth of subcutaneous LC xenografts by decreasing PD-L1 expression in severe combined immunodeficient mice.

CONCLUSIONS

Taken together, LINC01140 overexpression protects c-Myc and PD-L1 mRNA from miRNA-mediated inhibition and contributes to the proliferation, migration, invasion, and immune escape of LC cells. These results provide a theoretical basis that LINC01140 is a promising target for LC treatment.

[A preliminary investigation on a deep learning convolutional neural networks based pulmonary tuberculosis CT diagnostic model]

Objective: To evaluate the clinical value of a pulmonary tuberculosis CT diagnostic model based on deep learning convolutional neural networks (CNN). Methods: From March 2017 to March 2018,a total of 1 764 patients with positive sputum for tuberculous bacterium and had received high-resolution chest CT scan in radiology department of Hebei province chest hospital were enrolled. Among them, 937 were male, and 827 were female, aging from 17-73 years (average 38.4). A total of 20 139 CT images (17 kinds of image features) classified by 4 radiologists were used as training dataset to create a tuberculosis CT CNN diagnostic model. The top 5 image features in training set were: infiltrative pulmonary tuberculosis, cavitary pulmonary tuberculosis, pleural thickening, caseous pneumonia and pleural effusion. A total of 302 images were randomly selected from the marked images as testing dataset. The diagnosis of 2 senior radiologists was taken as "golden standard". The differences of sensitivity and accuracy in CT diagnosis between the CNN diagnostic model and the radiologists were compared. The classification error types and numbers of the CNN diagnostic model were recorded. FROC(free response operating characteristic curve)curve was drawn and the highest diagnostic efficiency of the model was measured. Results: The diagnostic accuracy of infiltrative pulmonary tuberculosis, cavitary pulmonary tuberculosis, pleural thickening, caseous pneumonia and pleural effusion by the CNN diagnostic model were 95.33%(10 982/11 520), 73.68%(2 151/2 920), 73.07%(1 128/1544), 83.33%(1 020/1225)and 94.11%(814/865), respectively. The overall diagnostic sensitivity and accuracy of the CNN model were 95.49%(339/355)and 90.40%(339/375), respectively, and the corresponding values ​​of radiologists were 93.80%(348/371)and 92.80%(348/375), respectively, and there was no statistical difference between the CNN model and the radiologists(sensitivity χ²=1.022,P=0.312;accuracy χ²=1.404,P=0.236). FROC curve showed that when sensitivity of the CNN model was 78% and FPI value was 2.48, it reached the highest diagnostic efficiency. The classification error of CNN diagnostic models was mainly confusion of fiber stripe components, cavitary pulmonary tuberculosis, caseous pneumonia and infiltrative pulmonary tuberculosis. Conclusions: The CNN-based pulmonary tuberculosis CT diagnostic model exhibited high sensitivity and accuracy (95.49% and 90.40% respectively). It could assist radiologists in CT diagnosis of pulmonary tuberculosis and deserve further clinical application.

Optimal margins for early stage peripheral lung adenocarcinoma resection

Background

A pathologically confirmed negative margin is required when performing sublobar resection in patients with early stage peripheral lung adenocarcinoma. However, the optimal margin distance to ensure complete tumor resection while preserving healthy lung tissue remains unknown. We aimed to establish a reliable distance range for negative margins.

Methods

A total of 52 intraoperative para-cancer tissue specimens from patients with peripheral lung adenocarcinoma with pathological tumors ≤2 cm in size were examined. Depending on the distance from the tumor edge (D), the para-cancer tissues were divided into the following five groups: D < 0.5 cm (group I); 0.5 cm ≤ D < 1.0 cm (group II); 1.0 cm ≤ D < 1.5 cm (group III); 1.5 cm ≤ D < 2.0 cm (group IV); and D ≥ 2.0 cm (group V). During pathological examination of the specimens under a microscope, the presence of atypical adenomatous hyperplasia or more severe lesions was considered unsafe, whereas the presence of normal lung tissue or benign hyperplasia was considered safe.

Results

Group V, in which the margin was the farthest from the tumor edge, was the safest. There were significant safety differences in between groups I and V (χ² = 26.217, P < 0.001). Significant safety differences also existed between groups II and V (χ² = 9.420, P < 0.005). There were no significant safety differences between group III or IV and group V (P = 0.207; P = 0.610).

Conclusions

We suggest that when performing sublobar resection in patients with early stage peripheral lung adenocarcinoma with pathological tumor sizes ≤2 cm, the resection margin distance should be ≥1 cm to ensure a negative margin.

Fe(II) interaction with cement phases: Method development, wet chemical studies and X-ray absorption spectroscopy

Fe(II) interaction with cement phases was studied by means of co-precipitation and sorption experiments in combination with X-ray absorption fine structure (XAFS) spectroscopy. Oxidation of Fe(II) was fast in alkaline conditions and therefore, a methodology was developed which allowed Fe(II) to be stabilised in the sorption experiments and to prepare samples for spectroscopy. X-ray diffraction (XRD) of the co-precipitation samples showed uptake of a small portion of Fe(II) by calcium-silicate-hydrates (C-S-H) in the interlayer indicated by an increase in the interlayer spacing. Fe(II) incorporation by AFm phases was not indicated. Wet chemical experiments using ⁵⁵Fe radiotracer revealed linear sorption of Fe(II) irrespective of the Ca/Si ratio of C-S-H and equilibrium pH. The K_d values for Fe(II) sorption on C-S-H are more than three orders of magnitude lower as compared to Fe(III), while they are comparable to those of other bivalent metal cations. XAFS spectroscopy showed Fe(II) binding by C-S-H in an octahedral coordination environment. The large number of neighbouring atoms rules out the formation of a single surface-bound Fe(II) species. Instead the data suggest presence of Fe(II) in a structurally bound entity. The data from XRD and XAFS spectroscopy suggests the presence of both surface- and interlayer-bound Fe(II) species.

Analysis of mutation detection of POLD1/pole in pan-cancer

3142

Background: Previous studies proved that mutation of POLD1 and POLE elevates base-substitution mutations and lead to the elevation of tumor mutation burden (TMB). Other signature needs to explore to identify driver mutations in these two genes. Methods: Using gene-panel target-capture next generation sequencing, we analyzed the TMB and POLD1/POLE mutation in 17383 tumor tissue or plasma ctDNA samples from different patients. Results: Tumor mutation burdens were calculated of all the 17383 samples. According to the present research and our panel, we use 10 and 100 Mut/Mb to define hypermutation and ultra-hypermutation. Samples with hypermutation possessed 18.8% (n = 3268) and ultra-hypermutation possessed 0.3% (n = 58). In unselected, hypermutation and ultra-hypermutation group, POLD1 or/and POLE mutations were identified in 3.5% (n = 625), 56.1% (n = 32) and 87.9%(n = 372) samples. There were 0.5% (n = 81), 17.0% (n = 73) and 87.7%(n = 51) identified more than one mutation. These results showed that POLD1 or/and POLE mutations were enriched in samples with high TMB. We screened every known POLE and POLD1 driver mutations. There were 22 ultra-hypermutation samples identified these mutations, including A456P(3), P286R(10), V411L(6), M444K(1), S459F(1) in POLE and R1016H(1) in POLD1. Interestingly, all of them were identified in microsatellite stable (MSS) samples, which suggest that driver mutation may enriched in MSS samples. These already known driver mutation was not detect in 24 high-level microsatellite instability (MSI-H) and ultra-hypermutation samples. We further analyzed 10 POLD1/POLE mutations in other 5 MSS and ultra-hypermutation samples. POLE L424V was a pathogenic germline mutation but not defined as a driver mutation clearly before. POLE P286C had not been biochemically characterized but had different residue with P286R in the same position. Others had not been biochemically characterized (R232H, A234T, V945M, S1064I, Y467H in POLD1, D462N and R749Q, E1956D in POLE). These mutations were potential driver mutations and further research need to be support. Conclusions: We found that not only POLD1 or/and POLE mutations were enriched in samples with high TMB, but also driver mutations were enriched in microsatellite stable tumors. Further researches need to continue to identify more driver mutations of POLD1 and POLE.

LncRNA-ATB Promotes Lung Squamous Carcinoma Cell Proliferation, Migration, and Invasion by Targeting microRNA-590-5p/NF90 Axis

Lung cancer with highest morbidity and mortality seriously threatens human health worldwide. Long noncoding RNAs (lncRNAs) exert important biological functions by acting as microRNA, which is implicated in tumorigenesis and cancer development. Previous work has reported that lncRNA-ATB expression was significantly upregulated in lung adenocarcinoma tissues and promoted tumor progression; however, the mechanisms of lncRNA-ATB in lung squamous carcinoma (LSC) are still fairly elusive. In our study, lncRNA-ATB expression also markedly increases in LSC tissues and cell lines in comparison to the adjacent normal tissues and normal lung epithelial cells, respectively. Functional experiments indicate that lncRNA-ATB overexpression improves the proliferative, migratory, and invasive capabilities of normal lung epithelial cells compared with control group. Furthermore, the migratory and invasive abilities are strikingly inhibited in lncRNA-ATB silenced LSC cells. Mechanistically, lncRNA-ATB directly binds to microRNA-590-5p and downregulates microRNA-590-5p level, leading to the upregulation of NF-90 expression. In addition, lncRNA-ATB overexpression promotes the epithelial-mesenchymal transition process, where lncRNA-ATB overexpression facilitates the expression of mesenchymal phenotype related molecules N-cadherin and vimentin, while restrains the expression of epithelial phenotype related proteins E-cadherin and CK-19, compared to the control. Conversely, microRNA-590-5p mimics can reverse the results caused by lncRNA-ATB overexpression. Taken together, our initial data suggest that lncRNA-ATB overexpression may promote the progression of LSC by modulating the microRNA-590-5p/NF-90 axis.

Aetiology and pathogenesis of paraneoplastic autoimmune disorders

Paraneoplastic autoimmune disorders (PAD) represent a group of autoimmune diseases associated with neoplasms. As a consequence of a remote autoimmunity-mediated effect, PAD are found in multiple organs or tissues, including the skin, blood and nervous system. Compared with non-paraneoplastic autoimmune diseases, PAD have different aetiologies, pathologies, disease symptoms and treatment responses. There are two main origins of autoimmunity in PAD: neoplasm-mediated dysregulated homeostasis in immune cells/organs and in autoantigens. Pathologically, PAD are mediated predominantly by either autoantibodies or autoreactive T-cells. In the past decade, significant progress has been achieved in increasing our understanding of the aetiology and pathology of PAD. In this review article, we aim to provide a comprehensive overview of the recent advances in this field.

Computed tomography-guided preoperative semi-rigid hook-wire localization of small pulmonary nodules: 74 cases report

OBJECTIVES

The study aimed to retrospectively evaluate the success rate, utility, practicality and results of pre-operative CT (computed tomography)-guided semi-rigid single hook-wire placement and the pathology results of small pulmonary nodules (SPN).

MATERIALS AND METHODS

Seventy-four patients with 81 small pulmonary nodules underwent CT-guided semi-rigid single hook wire localization consecutively between 2016 and 2017 were reviewed. VATS (video-assisted thoracoscopic surgery) resection of lung tissue containing each pulmonary nodule and were performed in the direction of hook wire. The success rate and utility of the localization, hook wire related complications, the histopathology of SPN are analyzed.

RESULTS

The semi-rigid hook wire was performed successfully in all 81 small pulmonary nodules within mean time of 10 min (8-13 min, SD: 1.58 min). Compared with solid nodules, GGOs (ground-glass opacity) were more frequently malignant (p < 0.05), with an OR (odds ratio) 8.59 (95%CI, 0.967, 412.845). Of the pure GGOs, 9 (25%) nodules were classified as AIS, 10 (27.8%) nodules were classified as MIA and 22 (57.9%) of the mGGOs were lung cancer. According to multivariate analysis, the malignant hazard was as high as 6.533-fold higher in nodules with a size larger than 10 mm compared with those smaller than 10 mm. GGOs with tiny blood vessels showed a statistically significant correlation with malignancy. Surprisingly, no statistically significant difference in the incidence of lung cancer in age. No major complication occurred.

CONCLUSIONS

Preoperative localization of small pulmonary nodules using semi-rigid single hook wire was found to be practical and safe, which allows for proper diagnosis. Incidental small pulmonary nodule, especially GGO larger than 10 mm needs to be taken seriously.

Repurposing the anti-malarial drug dihydroartemisinin suppresses metastasis of non-small-cell lung cancer via inhibiting NF-κB/GLUT1 axis

Non-small-cell lung cancer (NSCLC) is an aggressive malignancy and long-term survival remains unsatisfactory for patients with metastatic and recurrent disease. Repurposing the anti-malarial drug dihydroartemisinin (DHA) has been proved to possess potent antitumor effect on various cancers. However, the effects of DHA in preventing the invasion of NSCLC cells have not been studied. In the present study, we determined the inhibitory effects of DHA on invasion and migration and the possible mechanisms involved using A549 and H1975 cells. DHA inhibited in vitro migration and invasion of NSCLC cells even in low concentration with little cytotoxicity. Additionally, low concentration DHA also inhibited Warburg effect in NSCLC cells. Mechanically, DHA negatively regulates NF-κB signaling to inhibit the GLUT1 translocation. Blocking the NF-κB signaling largely abolishes the inhibitory effects of DHA on the translocation of GLUT1 to the plasma membrane and the Warburg effect. Furthermore, GLUT1 knockdown significantly decreased the inhibition of invasion, and migration by DHA. Our results suggested that DHA can inhibit metastasis of NSCLC by targeting glucose metabolism via inhibiting NF-κB signaling pathway and DHA may deserve further investigation in NSCLC treatment.

Semi-rigid single hook localization the best method for localizing ground glass opacities during video-assisted thoracoscopic surgery: re-aerated swine lung experimental and primary clinical results

Background

The aim of this study was to compare the effects of currently available preoperative localization methods, including semi-rigid single hook-wire, double-thorn hook-wire, and microcoil, in localizing the pulmonary nodules, thus to select the best technology to assist video-assisted thoracoscopic surgery (VATS) for small ground glass opacities (GGO).

Methods

Preoperative CT-guided localizing techniques including semi-rigid single hook-wire, double-thorn hook-wire and microcoil were used in re-aerated fresh swine lung for location experiments. The advantages and drawbacks of the three positioning technologies were compared, and then the most optimal technique was used in patients with GGO. Technical success and post-operative complications were used as primary endpoints.

Results

All three localizing techniques were successfully performed in the re-aerated fresh swine lung. The median tractive force of semi-rigid single hook wire, double-thorn hook wire and microcoil were 6.5, 4.85 and 0.2 N, which measured by a spring dynamometer. The wound sizes in the superficial pleura, caused by unplugging the needles, were 2 mm in double-thorn hook wire, 1 mm in semi-rigid single hook and 1 mm in microcoil, respectively. In patients with GGOs, the semi-rigid hook wires localizations were successfully performed, without any complication that need to be intervened. Dislodgement was reported in one patient before VATS. No major complications related to the preoperative hook wire localization and VATS were observed.

Conclusions

We found from our localization experiments in the swine lung that, among the commonly used three localization methods, semi-rigid hook wire showed the best operability and practicability than double-thorn hook wire and microcoil. Preoperative localization of small pulmonary nodules with single semi-rigid hook wire system shows a high success rate, acceptable utility and especially low dislodgement in VATS.

Inhibition of SRC-3 enhances sensitivity of human cancer cells to histone deacetylase inhibitors

SRC-3 is widely expressed in multiple tumor types and involved in cancer cell proliferation and apoptosis. Histone deacetylase (HDAC) inhibitors are promising antitumor drugs. However, the poor efficacy of HDAC inhibitors in solid tumors has restricted its further clinical application. Here, we reported the novel finding that depletion of SRC-3 enhanced sensitivity of breast and lung cancer cells to HDAC inhibitors (SAHA and romidepsin). In contrast, overexpression of SRC-3 decreased SAHA-induced cancer cell apoptosis. Furthermore, we found that SRC-3 inhibitor bufalin increased cancer cell apoptosis induced by HDAC inhibitors. The combination of bufalin and SAHA was particular efficient in attenuating AKT activation and reducing Bcl-2 levels. Taken together, these accumulating data might guide development of new breast and lung cancer therapies.

Comparison of the duration of neuromuscular blockade following a single bolus dose of rocuronium during laparoscopic gynaecological surgery vs conventional open surgery

We investigated whether laparoscopic vs open surgical approaches affected the duration of neuromuscular blockade following a single bolus dose of rocuronium. Fifty-three female patients underwent either laparoscopic or open gynaecological surgery. Rocuronium 0.6 mg.kg(-1) was administered to achieve neuromuscular blockade in all subjects, and adductor pollicis train-of-four responses following ulnar nerve stimulation were monitored with mechanomyography. The mean (SD) time from injection of rocuronium until spontaneous recovery of the first twitch, and to 5% and 25% of baseline, was significantly prolonged in the laparoscopic group (27.2 (8.3) min, 31.3 (9.1) min and 38.1 (10.6) min, respectively) compared with the open surgery group (21.1 (5.8) min, 25.6 (6.3) min and 31.2 (6.7) min, respectively). Changes in liver function both before surgery and at 24 h postoperatively were similar between the two groups (p > 0.05). Our findings suggest that neuromuscular blockade may be prolonged following a single bolus dose of rocuronium given during laparoscopic procedures.

Measuring anisotropic muscle stiffness properties using elastography

Physiological and pathological changes to the anisotropic mechanical properties of skeletal muscle are still largely unknown, with only a few studies quantifying changes in vivo. This study used the noninvasive MR elastography (MRE) technique, in combination with diffusion tensor imaging (DTI), to measure shear modulus anisotropy in the human skeletal muscle in the lower leg. Shear modulus measurements parallel and perpendicular to the fibre direction were made in 10 healthy subjects in the medial gastrocnemius, soleus and tibialis anterior muscles. The results showed significant differences in the medial gastrocnemius (μ‖ = 0.86 ± 0.15 kPa; μ⊥ = 0.66 ± 0.19 kPa, P < 0.001), soleus (μ‖ = 0.83 ± 0.22 kPa; μ⊥ = 0.65 ± 0.13 kPa, P < 0.001) and the tibialis anterior (μ‖ = 0.78 ± 0.24 kPa; μ⊥ = 0.66 ± 0.16 kPa, P = 0.03) muscles, where the shear modulus measured in the direction parallel is greater than that measured in the direction perpendicular to the muscle fibres. No significant differences were measured across muscle groups. This study provides the first direct estimates of the anisotropic shear modulus in the triceps surae muscle group, and shows that the technique may be useful for the probing of mechanical anisotropy changes caused by disease, aging and injury.

Arthritis prevalence and place of birth: findings from the 1994 Canadian National Population Health Survey

This paper describes the prevalence of arthritis in Canadians by ethnic origin, including Asians, Europeans/Australians, and North American-born Canadians. Data for this study were derived from the 1994 Canadian National Population Health Survey, a cross-sectional survey with a sample of 39,240 persons aged 20 years and older. Arthritis was defined as a long-term health condition of "arthritis or rheumatism" diagnosed by a health professional. Place of birth was determined according to self-reported country of birth. Unconditional multiple logistic regression models were used to adjust for potential confounding effects. The crude prevalence of self-reported arthritis and rheumatism diagnosed by a health professional as a long-term condition for those aged 20 years and older in Canada was 14.2%. The age-sex adjusted prevalence by place of birth was 6.9% in Asians, 14.2% in Europeans/Australians, and 14.5% in North American-born Canadians. In the multivariate analyses using North America-born Canadians as baseline, the risk for arthritis (odds ratio = 0.56) was significantly lower in Asian-born Canadians after adjustment for age, sex, education, income, occupation, and body mass index.

Role of L-type Ca2+ channel in PACAP-induced adrenal catecholamine release in vivo

The aim of the present study was to investigate whether the dihydropyridine-sensitive L-type Ca2+ channel is operative in adrenal catecholamine (CA) secretion induced by a novel neuropeptide, pituitary adenylate cyclase-activating polypeptide (PACAP), in anesthetized dogs. Plasma CA concentrations in adrenal venous and aortic blood were determined by a high-performance liquid chromatography method. All drugs tested were locally infused into the left adrenal gland via the left adrenolumbar artery. PACAP, with the isoform consisting of 27 (PACAP-27) and 38 (PACAP-38) amino acid residues, significantly increased CA output in a dose-dependent manner, with doses ranging from 5 to 500 ng and 7 to 700 ng, respectively. However, the amplitude of epinephrine response to PACAP-27 was three times greater than that obtained with PACAP-38 at the highest dose tested. In a separate group, a single dose of PACAP-27 (50 ng) induced highly reproducible CA responses when the same dose was repeated with an interval of 35 min. In dogs treated with nifedipine (50 microg), 5 min before the second administration of PACAP-27, the net CA response was significantly inhibited by approximately 50% compared with that obtained in the presence of vehicle. A similar CA response to BAY K 8644 (5 microg) was completely abolished by the same dose of nifedipine. The present results indicate that both PACAP-27 and PACAP-38 have the direct local secretagogue effect on the adrenal medulla in vivo and that CA responses to PACAP-27 were greater than those observed with PACAP-38 at equivalent mole doses. The study suggests that the dihydropyridine-sensitive L-type Ca2+ channel is functionally involved in PACAP-induced adrenal CA secretion in the canine adrenal medulla in vivo.

Prehospital thrombolysis in acute myocardial infarction

The benefit and risk of prehospital thrombolysis for acute myocardial infarction (AMI) were evaluated in a double-blind randomized trial. Patients presenting less than 4 hours after symptom onset received 2 million units of urokinase as an intravenous bolus either before (group A, n = 40) or after (group B, n = 38) hospital admission. The mean time interval from onset of symptoms to thrombolytic therapy was 85 +/- 51 minutes in group A and 137 +/- 50 minutes in group B (p less than 0.0005). In 91% of the patients, thrombolytic therapy was administered less than 3 hours after symptom onset. Complication rates during the pre- and in-hospital period were low and did not differ between groups. Three patients died (1 in group A, 2 in group B) from reinfarction 7 to 14 days after admission. Left-sided cardiac catheterization before discharge revealed a patency rate in the infarct-related artery of 61% in group A and 67% in group B (difference not significant). Global left ventricular function and regional wall motion at the infarct site did not differ significantly between group A and B (ejection fraction 51 +/- 10%, n = 28 vs 53 +/- 14%, n = 28; wall motion -2.3 +/- 1.3 vs -2.2 +/- 1.1 standard deviation, respectively). Also, peak creatine kinase did not differ significantly (838 +/- 634 U/liter in group A vs 924 +/- 595 U/liter in group B). Prehospital thrombolysis using a bolus injection of urokinase has a low risk when performed by a trained physician with a mobile care unit. The saving of 45 minutes in the early stage of an acute infarction through prehospital thrombolysis did not appear to be important for salvage of myocardial function.

[The thrombolysis treatment of acute myocardial infarct at the site of the emergency. A randomized double-blind study]

Two million units of urokinase were administered intravenously as a bolus, either before (group I, n = 40) or after hospital admission (group II, n = 38), to 66 men and 12 women (mean age 55 +/- 8 years) with typical symptoms of acute myocardial infarction of less than 4 hours' duration. Time elapsed between onset of symptoms and urokinase administration averaged 85 +/- 51 min for group I and 137 +/- 50 min for group II (P less than 0.005). The complication rate was low, both during the pre-hospital and the hospital phases, without any significant differences between the two groups. The rate of open infarct vessels (by angiography before discharge from hospital) was 61% for group I and 67% for group II (no significant difference). Global left ventricular function, regional wall motion in the infarct area and maximal creatinekinase values did not significantly differ between the two groups (ejection fraction 51 +/- 10% and 53 +/- 14%, respectively; creatinekinase 838 +/- 634 U/l and 924 +/- 595 U/l, respectively). The data indicate that thrombolytic pre-hospital treatment carried a low risk. The gain of 45 min, however, seems to be of secondary importance in any significant diminution of the acute infarction size.