Podophyllotoxin-loaded PEGylated E-selectin peptide conjugate targeted cancer site to enhance tumor inhibition and reduce side effect

E-selectin, which is highly expressed in vascular endothelial cells near tumor and get involved in the all tumor growth steps: occurrence, proliferation and metastasis, is considered as a promise targeted protein for antitumor drug discovery. Herein, we would like to report the design, preparation and the anticancer evaluation of the peptide-PEG-podophyllotoxin conjugate(PEG-Pep-PODO), in which the short peptide (CIELLQAR) was used as the E-selectin ligand for the targeting purpose and the PEG portion the molecule got the conjugate self-assembled to form a water soluble nanoparticle. In vitro release study showed that the conjugated and entrapped PODO could be released simultaneously in the presence of GSH (highly expressed in tumor environmental conditions) and the GSH would catalyze the break of the disufur bond which linked of the PODO and the peptide-PEG portion of the conjugate. Cell adhesion test of the PEG-Pep-PODO indicated that E-selectin ligand peptide CIELLQAR could get specifically and efficiently binding to the E-selectin expressing human umbilical vein endothelial cells (HUVEC). In vitro cytotoxicity assay further revealed that PEG-Pep-PODO significantly improved the selectivity of PEG-Pep-PODO for killing the tumor cells and normal cells compared with PODO solution formulation. More importantly, the in vivo experiment demonstrated that the conjugate would accumulate of the PODO payload in tumor through targeting endothelial cells in the tumor microenvironment, which resulted in the much improved in vivo inhibition of tumor growth, intratumoral microvessel density, and decreased systemic toxicity of this nanoparticle over the free PODO. Furthermore, this water soluble conjugate greatly improved the pharmacokinetic properties of the mother molecule.

The Role of Radiation Therapy for Metastatic Cervical Cancer

PURPOSE/OBJECTIVE(S)

Survival rates for women with metastatic cervical cancer (CC) are low, with limited management options. Radiation therapy (RT) for metastatic disease has led to prolonged survival in other malignancies, however, the data are scarce in CC. Herein, we evaluated the effect of RT for metastatic CC.

MATERIALS/METHODS

A total of 58 patients with metastatic CC between September 2019 and January 2023 were retrospectively analyzed. All the patients were treated with platinum-based chemotherapy combined with targeted therapy or immunotherapy followed with or without RT (NRT). The recent efficacy, survival status and prognostic factors were analyzed statistically.

RESULTS

Objective response rate (ORR) was 63.6% with one complete and twenty partial responses in RT group (n = 33) and 40.0% with two complete and eight partial responses in NRT group (n = 25), respectively (p = 0.074). Disease control rate (DCR) of the RT and NRT groups were 79.4% vs 80.0%, respectively (p = 0.861). Median follow-up time was 17 months (3-39months). In RT group, 11(33.3%) patients experienced local regional or distant failure and 9 (27.3%) patients were dead. In NRT group, 15(60%) patients had progression and 8 (32%) patients dead. There was no significant difference between the two groups in overall survival (OS); however, RT group displayed superior progression-free survival (PFS) (1-year OS: 72.7% vs. 68.0%, p = 0.460; 1-year PFS: 66.7% vs. 40.0%, p = 0.039). The multivariate analysis showed that RT, immunotherapy, lymph node metastasis only relevant predictor of superior PFS but not OS. In subgroup analysis, patients treated with RT appeared to have a better PFS in some specific cohorts, such as age>45 years (72.0% vs 36.4% P = 0.015), squamous carcinoma histology (71.0% vs 40.9% P = 0.017), metastatic at diagnosis (75.0% vs 47.6% P = 0.012), non-targeted therapy (72.4% vs 43.8% P = 0.040). No significant increase in treatment-related toxicity was observed in the RT group compared with the NRT group.

CONCLUSION

RT provided superior PFS in metastatic CC patients compared to NRT, and well tolerated. Moreover, RT, immunotherapy, lymph node metastasis only were independent significant prognostic factors for PFS. Subgroup analysis showed that combination of RT and chemotherapy obtained favorable PFS in metastatic CC patients with age>45 years, squamous carcinoma histology, metastatic at diagnosis, non-targeted therapy. Studies with a larger sample size and longer follow-up are warranted.

RUNX1 as a Potential Target for Combined Radioimmunotherapy of Lung Adenocarcinoma

PURPOSE/OBJECTIVE(S)

Radioimmunotherapy for non-small cell lung cancer has good clinical application prospects. The role and mechanism of RUNX1 in DNA damage repair were explored for its potential role in lung adenocarcinoma radioimmunotherapy.

MATERIALS/METHODS

To study the effect of RUNX1 expression level on the expression of DNA damage repair system related factors and radiation sensitivity of lung adenocarcinoma cells. As an important nuclear transcription factor, RUNX1 was explored whether directly regulating the expression of Nrf2, Rad51, BRCA1, and verifying their respective DNA binding sites in the promoter region through relevant databases. To observe the effect of RUNX1 knockout and overexpression on the expression level of PD-L1 in tumor cells at the cell level; The effect of RUNX1 expression level on the sorting and presentation of PD-L1 cells was investigated by the method of nucleocytoplasmic separation. According to literature reports, CMTM6 and ALIX play a key role in the process of PD-L1 cell sorting and presentation, and explore whether RUNX1 plays a role through this factor. The effect of phosphorylation level of different splicing bodies of RUNX1 (RUNX1a/b/c) on the expression level and DNA damage repair system related factors on tumor radiosensitivity were also explored.

RESULTS

According to TCGA database, RUNX1 is highly expressed and phosphorylated in lung adenocarcinoma. Through gene comparison with the database, it was found that RUNX1 binding sites existed in the promoter region of several factors related to this study, including ALIX, Nrf2, BRCA1, RAD51, ATM, H2AX, etc. After being activated by MAPKp38 phosphorylation, RUNX1a can positively regulate Nrf2 signal pathway. The expression of RUNX1 and p-RUNX1 is time-dependent on ionizing radiation. At the same time, it was found that the expression of RUNX1 and p-RUNX1 was dose-dependent on ionizing radiation, and the expression trend of Nrf2 signal pathway related factors was consistent with RUNX1. RUNX1 regulates the expression of PD-L1, BRCA1, ALIX and Nrf2. Bioinformatics analysis and flow cytometry data show that RUNX1 has inhibitory effect on tumor microenvironment of lung adenocarcinoma.

CONCLUSION

RUNX1 regulates DNA damage repair system and has inhibitory effect on tumor immunity. Inhibiting the expression of RUNX1 in lung adenocarcinoma cells can enhance the effect of radioimmunotherapy.

Cost-Effectiveness of Short-Course Radiotherapy Based Total Neoadjuvant Therapy for Locally Advanced Rectal Cancer in China

PURPOSE/OBJECTIVE(S)

The phase III STELLAR (NCT02533271) trial demonstrated that four cycles of chemotherapy after short-course radiotherapy (SCRT-TNT) were not inferior to the standard care of long-course concurrent radiotherapy (LCRT) in patients with locally advanced rectal cancer (LARC). This study assessed the cost-effectiveness of SCRT-TNT versus LCRT in locally advanced rectal cancer in China on the basis of the STELLAR trial.

MATERIALS/METHODS

A Markov model was used to synthesize the healthcare costs and benefits of LARC patients based on results from the STELLAR trial. The model assumes that LARC who meet the inclusion criteria of the STELLAR trial experience four possible states: No Evidence of Disease (NED), locally recurrence, distant metastases, or any death from rectal cancer or other unrelated causes, where local recurrence continues to be classified as resectable and unresectable. The transition status period is 3 month, and 5 years is used to calculate direct medical costs and health benefits. The probabilities of states transition after SCRT-TNT or LCRT were derived from the results of the STELLAR trial and previous published article (Table.1). Costs were evaluated from the Chinese payer's perspective reported in early 2022 US dollars (US$1 = 6.78 Chinese Yuan). Sensitivity analyses were performed for key variables. Cost-effectiveness was evaluated using the incremental cost-effectiveness ratio and net monetary benefits. Effectiveness was defined as quality-adjusted life-years (QALYs). Willingness-to-pay (WTP) threshold was set at $43500/QALY. Data were collected from October 3, 2020, to September 20, 2021, and analyzed from November 15, 2020, to October 25, 2021.

RESULTS

During the 5-year horizon, for the base case scenario, SCRT-TNT incurred a lower total cost and higher QALYs compared with LCCRT. The total cost was $65767 and QALYs were 1.77 for SCRT-TNT; for LCCRT, the total cost was $72802 and QALYs were 1.64. This resulted in an ICER of -$ 55470.69 per QALY. Therefore, SCRT-TNT was a cost-saving and dominating treatment strategy compared with LCRT. Sensitivity analysis showed that ICERs were most sensitive to the parameters of distant metastases risk after treatment.

CONCLUSION

SCRT-TNT in locally advanced rectal cancer can be a cost-effective alternative to LCRT in China, and should be considered in appropriately selected patients.

Pseudo CT Synthesis Using Cone-Beam CT of Cervical Cancer with GAN-Based Neural Network Model

PURPOSE/OBJECTIVE(S)

Cervical cancer (CC) is a tumor disease that threatens the health of women. As an important treatment of CC, radiotherapy has been widely used in clinic. With the rapid development of radiotherapy technology, adaptive radiotherapy has received much attention. Adaptive radiotherapy means more accurate radiation dose and more accurate radiation area, which can effectively protect normal tissue. It is significant to improve the local control rate of tumor and the quality of life of patients. However, the Cone-Beam CT (CBCT) images collected during radiotherapy are of poor quality and cannot provide real-time radiation effect information, resulting in timely and effective adjustment of radiation dose and radiation area in the process of radiotherapy for cervical cancer. To alleviate this issue, this study will establish a model to leverage CC CBCT images to synthetize pseudo computed tomography (CT) images with high quality, so as to achieve the purpose of quality improvement.

MATERIALS/METHODS

This study included the data of 20 patients with CC in ** hospital. The planning CT and CBCT scan data of each patient before radiotherapy were collected, and the interval between the two kinds of image data was required to be less than one week. After data preprocessing, a total of 1206 pairs of images were trained and tested. The generative adversarial network (GAN) is constructed. In order to ensure the similarity between the input image and the output image, the L1 loss function is leveraged. And the full supervision method is used to train the model to achieve a better effect of image synthesis and improve the quality of CBCT image. Peak signal-to-noise ratio (PSNR) and structural similarity (SSIM) were used as evaluation indexes.

RESULTS

Using five-fold cross-validation, the values of PSNR between the pseudo-CT (sCT) and the planning CT (pCT) image and between the CBCT and the pCT image are calculated. The results are 26.9 and 22.6, respectively. The sCT obtained from the GAN model increases the peak signal-to-noise ratio by 19% compared with the original CBCT, which means that the proposed model built in this study can improve the useful information of the CBCT image. The SSIM values between sCT and pCT and between CBCT and pCT are also calculated, and the average values of them are 0.89 and 0.63, respectively. Therefore, in this experiment, the structure of the sCT obtained by the proposed model is closer to pCT. And the SSIM increases by 41.2% compared with the original CBCT, which means that the sCT by the proposed model is more similar to the pCT in structure. These results could make a more accurate judgment on the effect of radiotherapy.

CONCLUSION

In this study, the pseudo-CT synthesis method based on GAN can improve the quality of CC CBCT image. The results show this method makes the structure clearer and could assist doctors to adjust the radiation dose and radiation area in time. This study is able to facilitate the development of adaptive radiotherapy for CC.

Serum Anti-Fumarate Hydratase Autoantibody as a Biomarker for Predicting Prognosis of Acute-on-Chronic Liver Failure

Background/Aims

To investigate the autoantibody against fumarate hydratase (FH), which is a specific liver failure-associated antigen (LFAA) and determine whether it can be used as a biomarker to evaluate the prognosis of acute-on-chronic liver failure (ACLF).

Methods

An immunoproteomic approach was applied to screen specific LFAAs related to differential prognosis of ACLF (n=60). Enzyme-linked immunosorbent assay (ELISA) technology was employed for the validation of the frequency and titer of autoantibodies against FH in ACLF patients with different prognoses (n=82). Moreover, we clarified the expression of autoantibodies against FH in patients with chronic hepatitis B (n=60) and hepatitis B virus-related liver cirrhosis (n=60). The dynamic changes in the titers of autoantibodies against FH were analyzed by sample collection at multiple time points during the clinical course of eight ACLF patients with different prognoses.

Results

Ultimately, 15 LFAAs were screened and identified by the immunoproteomic approach. Based on ELISA-based verification, anti-FH/Fumarate hydratase protein autoantibody was chosen to verify its expression in ACLF patients. ACLF patients had a much higher anti-FH autoantibody frequency (76.8%) than patients with liver cirrhosis (10%, p=0.000), patients with chronic hepatitis B (6.7%, p=0.022), and normal humans (0%, p=0.000). More importantly, the frequency and titer of anti-FH protein autoantibodies in the serum of ACLF patients with a good prognosis were much higher than that of patients with a poor prognosis (83.9% vs 61.5%, p=0.019; 1.41±0.85 vs 0.94±0.56, p=0.017, respectively). The titer of anti-FH autoantibodies showed dynamic changes in the clinical course of ACLF.

Conclusions

The anti-FH autoantibody in serum may be a potential biomarker for predicting the prognosis of ACLF.

[Discussion from metabolism to fatty liver disease: rethinking the origin of disease and the endpoint of new drugs or metabolic dysfunction-associated steatotic liver disease]

The diagnosis of nonalcoholic fatty liver disease (NAFLD) is an exclusionary diagnosis, and the name does not reflect the disease's nature or mechanism. Internationally, MAFLD (metabolic dysfunction-associated fatty liver disease) and MASLD (metabolic dysfunction-associated steatotic liver disease) have recently been proposed, which are translated as metabolic dysfunction-associated fatty liver disease in Chinese. The new name reflects the initiating factors of the disease, its occurrence and development process, and the clinical significance of associated outcomes. Through interventions against metabolic disorders, liver disease (hepatic manifestations of systemic disease) reflecting MASLD (MAFLD) has the potential to improve clinical outcomes.

[Interpretation of the important update of the Guideline for the prevention and treatment of hepatitis C (2022 edition)]

In the past 20 years, Chinese Medical Association had issued several versions of hepatitis C prevention and treatment guidelines. In the latest guidelines published in 2022, the Chinese Society of Hepatology and the Society of Infectious Diseases for the Chinese Medical Association organized experts to update their recommendations for hepatitis C screening and treatment. The updated key points on prevention, diagnosis, and treatment proposed in the guidelines are now interpreted, aiming to provide reference for more effective clinical application of the guidelines.

[Ten-year changes in clinical characteristics and antiviral treatment patterns of chronic hepatitis B in China: a CR-HepB-based real-world study]

Objective: To understand ten-year changes in clinical characteristics and antiviral treatment patterns of chronic hepatitis B in China. Methods: Patients with chronic HBV infection:demographic, virologic, hematologic, blood biochemistry, and antiviral treatment data were extracted from the China Registry of Hepatitis B (CR-HepB) database between 2012 and 2022 for descriptive statistics and change trend analysis. Multiple group comparisons were conducted using the Kruskal Wallis H test, while counting data was compared between groups using χ (2) test. Results: A total of 180 012 patients with chronic HBV infection were included, with a median age of 40 years old, and a male proportion accounting for 60.2%. The HBeAg positive rate was 43.3%. Over time, the median age of new patients each year increased from 39 to 47 years, while the HBeAg positive rate decreased from 51.3% to 32.8%. The initial diagnosis of patients was mainly CHB (71.4%), followed by hepatitis B cirrhosis (11.8%), inactive HBsAg carrier status (10.6%), and chronic HBV carrier status (6.2%). Among the newly registered patients every year from 2012 to 2022, the proportion of hepatitis B cirrhosis remained stable, but after 2019, the proportion of CHB increased and the proportion of other diagnoses decreased. The proportion of patients with cirrhosis increased with age in different age groups, with 3.5%, 19.3%, and 30.4% in the < 40, 40-69, and≥70 age groups, respectively. The proportion of women in patients with cirrhosis also increased with age, from 16.1% in those < 30 years old to 44.3% in those≥80 years old. From 2012 to 2022, the proportion of patients receiving first-line nucleos(t)ide analog antiviral treatment increased year by year, from 51.0% in 2012-2013 to 99.8% in 2022. Conclusion: The CR-HepB registration data reflect the changes in clinical characteristics and antiviral treatment patterns in patients with chronic HBV infection in China over the past ten years and can thus provide a reference to promote hepatitis B diagnosis and treatment practice, as well as scientific research.

Global burden of ischemic heart disease attributable to high sugar-sweetened beverages intake from 1990 to 2019

BACKGROUND AND AIMS

Excessive sugar-sweetened beverages (SSBs) intake is associated with a higher risk of ischemic heart disease (IHD). However, global patterns and trends in the burden of IHD attributable to high SSBs intake have not been systematically assessed.

METHODS AND RESULTS

We retrieved data from the Global Burden of Disease Study (GBD) 2019. We obtained the numbers and age-standardized mortality rate (ASMR) and disability-adjusted life years (DALYs) rate (ASDR) of IHD attributable to high SSBs intake by sex, year, socio-demographic index (SDI), and country between 1990 and 2019. Furthermore, we used a validated decomposition algorithm to attribute changes to population growth, population aging, and epidemiologic changes in the 21 GBD regions. From 1990 to 2019, the global IHD mortality attributable to high SSBs intake, as quantified by ASMR and ASDR declined significantly, while the burden increased saliently in absolute numbers. Population decomposition suggested that changes in epidemiology in most GBD regions have reduced IHD mortality due to high SSBs intake, but this trend has been counteracted by population growth and aging.

CONCLUSIONS

Although the age-standardized rate of IHD deaths and DALYs attributable to high SSBs intake decreased overall from 1990 to 2019, the absolute IHD burden remains high in some countries, especially in some developing countries in Asia and Oceania. Action is needed to enhance the prevention of diseases associated with high SSBs intake.

Crosstalk between colorectal cancer cells and cancer-associated fibroblasts in the tumor microenvironment mediated by exosomal noncoding RNAs

Colorectal cancer (CRC) is a common malignant tumor of the digestive system, and its morbidity rates are increasing worldwide. Cancer-associated fibroblasts (CAFs), as part of the tumor microenvironment (TME), are not only closely linked to normal fibroblasts, but also can secrete a variety of substances (including exosomes) to participate in the regulation of the TME. Exosomes can play a key role in intercellular communication by delivering intracellular signaling substances (e.g., proteins, nucleic acids, non-coding RNAs), and an increasing number of studies have shown that non-coding RNAs of exosomal origin from CAFs are not only closely associated with the formation of the CRC microenvironment, but also increase the ability of CRC to grow in metastasis, mediate tumor immunosuppression, and are involved in the mechanism of drug resistance in CRC patients receiving. It is also involved in the mechanism of drug resistance after radiotherapy in CRC patients. In this paper, we review the current status and progress of research on CAFs-derived exosomal non-coding RNAs in CRC.

[Interpretation of the essential updates in guidelines for the prevention and treatment of chronic hepatitis B (Version 2022)]

Chinese Society of Hepatology and Chinese Society of Infectious Diseases, Chinese Medical Association update the guidelines for the prevention and treatment of chronic hepatitis B (version 2022) in 2022. The latest guidelines recommend more extensive screening and more active antiviral treating for hepatitis B virus infection. This article interprets the essential updates in the guidelines to help deepen understanding and better guide the clinical practice.

[Utilizing ultra-small volume graft in auxiliary liver transplantation for portal hypertension]

Objective: To examine the clinical effect of auxiliary liver transplantation with ultra-small volume graft in the treatment of portal hypertension. Methods: Twelve cases of portal hypertension treated by auxiliary liver transplantation with small volume graft at Liver Transplantation Center,Beijing Friendship Hospital, Capital Medical University between December 2014 and March 2022 were studied retrospectively. There were 8 males and 4 females,aged 14 to 66 years. Model for end-stage liver disease scores were 1 to 15 points and Child scores were 6 to 11 points. The grafts was derived from living donors in 9 cases,from split cadaveric donors in 2 cases,from whole cadaveric liver of child in 1 case. The graft recipient body weight ratios of 3 cadaveric donor livers were 0.79% to 0.90%, and of 9 living donor livers were 0.31% to 0.55%.In these cases, ultra-small volume grafts were implanted. The survivals of patient and graft, complications, portal vein blood flow of residual liver and graft, abdominal drainage and biochemical indexes of liver function were observed. Results: All the grafts and patients survived. Complications included outflow tract torsion in 2 cases, acute rejection in 1 case, bile leakage in 1 case, and thyroid cancer at the later stage of follow-up in 1 case, all of which were cured. The torsion of outflow tract was attributed to the change of anastomotic angle after the growth of donor liver. After the improvement of anastomotic method, the complication did not recur in the later stage. There was no complication of portal hypertension. The measurement of ultrasonic portal vein blood flow velocity showed that the blood flow of residual liver decreased significantly in the early stage after operation, and maintained a very low blood flow velocity or occlusion in the long term after operation, and the blood flow of transplanted liver was stable. Conclusions: Auxiliary liver transplantation can implant ultra-small donor liver through compensation of residual liver. This method may promote the development of living donor left lobe donation and split liver transplantation. However, the auxiliary liver transplantation is complex, and it is difficult to control the complications. Therefore, this method is currently limited to centers that are skilled in living related liver transplantation and that have complete ability to monitor and deal with complications.

Development and validation of a risk score (Delay-7) to predict the occurrence of a treatment delay following cycle 1 chemotherapy

BACKGROUND

The risk of toxicity-related dose delays, with cancer treatment, should be included as part of pretreatment education and be considered by clinicians upon prescribing chemotherapy. An objective measure of individual risk could influence clinical decisions, such as escalation of standard supportive care and stratification of some patients, to receive proactive toxicity monitoring.

PATIENTS AND METHODS

We developed a logistic regression prediction model (Delay-7) to assess the overall risk of a chemotherapy dose delay of 7 days for patients receiving first-line treatments for breast, colorectal and diffuse large B-cell lymphoma. Delay-7 included hospital treated, age at the start of chemotherapy, gender, ethnicity, body mass index, cancer diagnosis, chemotherapy regimen, colony stimulating factor use, first cycle dose modifications and baseline blood values. Baseline blood values included neutrophils, platelets, haemoglobin, creatinine and bilirubin. Shrinkage was used to adjust for overoptimism of predictor effects. For internal validation (of the full models in the development data) we computed the ability of the models to discriminate between those with and without poor outcomes (c-statistic), and the agreement between predicted and observed risk (calibration slope). Net benefit was used to understand the risk thresholds where the model would perform better than the 'treat all' or 'treat none' strategies.

RESULTS

A total of 4604 patients were included in our study of whom 628 (13.6%) incurred a 7-day delay to the second cycle of chemotherapy. Delay-7 showed good discrimination and calibration, with c-statistic of 0.68 (95% confidence interval 0.66-0.7), following internal validation and calibration-in-the-large of -0.006.

CONCLUSIONS

Delay-7 predicts a patient's individualised risk of a treatment-related delay at cycle two of treatment. The score can be used to stratify interventions to reduce the occurrence of treatment-related toxicity.

Treatment of Hepatitis E

Hepatitis E virus (HEV) infections are the most common cause of acute hepatitis, but they can also take a chronic course. There is no specific therapy for acute hepatitis, and current treatment is supportive. Choosing ribavirin as the first-line therapy for chronic HEV is advisable, especially immunosuppressed individuals. Moreover, ribavirin therapy in the acute phase of infection provides major benefits for those at high risk of acute liver failure (ALF)/acute-on-chronic liver failure (ACLF). Pegylated interferon α has been used successfully for treatment of hepatitis E but is associated with major side effects. Cholestasis is one of the most common, but devastating, manifestations in hepatitis E. Current therapy for HEV aims to treat symptoms. Therapy generally involves several measures, such as vitamins, albumin, and plasma for supporting treatment, symptomatic treatment for cutaneous pruritus, ursodeoxycholic acid, Obeticholic acid, S-adenosylmethionine, etc. for removing jaundice. HEV infection during pregnancy and patients with underlying liver disease may develop liver failure. For these patients, active monitoring, standard care, and supportive treatment are the foundations. Ribavirin has successfully been used to prevent liver transplantation (LT). Prevention and treatment of complications are important for treatment of liver failure. Liver support devices are intended to support liver function until such time as native liver function recovers, or until LT. LT is widely considered as irreplaceable and definitive treatment for liver failure, particularly for patients who do not improve with supportive measures to sustain life.

[Influencing factors for postoperative survival of patients with pneumoconiosis treated by lung transplantation]

Objective: To explore the influencing factors for postoperative survival of patients with pneumoconiosis (silicosis) after lung transplantation in order to improve their clinical outcomes. Methods: In August 2021, retrospective alalysis from December 2015 to July 2021, 29 patients with end-stage pneumoconiosis underwent lung transplantation at Department of Thoracic Surgery, Affiliated Henan Provincial People's Hospital, Zhengzhou University. The survival, postoperative complications, and causes of death were analyzed. Life table and Kaplan-Meier method were used to draw survival curves, the log-rank test was used to compare the influence of each factor on survival rates, and the multivariate Cox proportional hazards regression model was used to evaluate the influence of each factor on survival. Results: All the patients underwent successful lung transplantation, with survival rates of 75% at 6 months, 70% at 1 year, 65% at 2 years, 50% at 3 years and 50% at 5 years. The Kaplan-Meier survival analysis showed that BMI, age and preoperative albumin level were influencing factors for postoperative survival rates (P<0.05) . The multivariate COX regression model showed that BMI≥18.5 kg/m(2) and the albumin level≥35 g/L were the protective factors (P<0.05) . Conclusion: Aging older, preoperative BMI<18.5 kg/m(2) and hypoalbuminemia are independent risk factors for death after lung transplantation. Survival rates are affected by preoperative BMI index, albumin level and age. Early intervention should be made before lung transplantation to promote the BMI index and albumin level to reach the standard.

Different Features of a Metabolic Connectivity Map and the Granger Causality Method in Revealing Directed Dopamine Pathways: A Study Based on Integrated PET/MR Imaging

BACKGROUND AND PURPOSE

Exploring the directionality of neural information in the brain is important for understanding brain mechanisms and neurodisease development. Granger causality analysis and the metabolic connectivity map can be used to investigate directional transmission of information between brain regions, but their differences in depicting functional effective connectivity are not clear.

MATERIALS AND METHODS

Using the Monash rs-PET/MR imaging data set, we conducted Granger causality and metabolic connectivity map analyses of the dopamine reward circuit in the brain. The dopamine reward circuit is a well-known system consisting primarily of the bilateral orbital frontal cortex, caudate, nucleus accumbens, thalamus, and substantia nigra. We validated these circuit pathways using Granger causality and the metabolic connectivity map for identifying effective connectivities against a priori knowledge by testing the significance of directed pathways (P < .05, false discovery rate-corrected).

RESULTS

We found 3 types of effective connectivities in the dopamine reward circuit: long-range, neighborhood, and symmetric. Granger causality analysis revealed long-range connections in the orbital frontal cortex-caudate and orbital frontal cortex-nucleus accumbens regions. Metabolic connectivity map analysis revealed neighborhood connections in the nucleus accumbens-caudate, substantia nigra-thalamus, and thalamus-caudate regions. Metabolic connectivity map analysis also found symmetric connections in each of the bilateral nucleus accumbens, caudate, thalamus, and orbital frontal cortex-caudate regions. Different patterns in directional networks of the dopamine reward circuit were revealed by Granger causality and metabolic connectivity map analyses.

CONCLUSIONS

Granger causality analysis primarily identified bidirectional cortico-nucleus connections, while the metabolic connectivity map primarily identified direct connections among neighborhood and symmetric regions. The results of this study indicated that investigations of effective connectivities should use an appropriate analysis method depending on the purpose of the study.