[HCV antigen detection method and clinical application]

Hepatitis C is distributed worldwide and possesses a hidden characteristic. The traditional methods of screening and diagnosis of hepatitis C infection commonly used in clinics are based on anti-HCV antibody and HCV RNA detection. Advances in HCV antigen detection technologies can apparently reduce the window period for anti-HCV antibodies, providing new clinical evidence for the early detection, diagnosis, and treatment of HCV infection. This article is a current review of HCV antigen detection methodologies, clinical applications, and detection strategies.

A zebrafish NLRX1 isoform downregulates fish IFN responses by targeting the adaptor STING

In mammals, NLRX1 is a unique member of the nucleotide-binding domain and leucine-rich repeat (NLR) family showing an ability to negatively regulate IFN antiviral immunity. Intron-containing genes, including NLRX1, have more than one transcript due to alternative splicing; however, little is known about the function of its splicing variants. Here, we identified a transcript variant of NLRX1 in zebrafish (Danio rerio), termed NLRX1-tv4, as a negative regulator of fish IFN response. Zebrafish NLRX1-tv4 was slightly induced by viral infection, with an expression pattern similar to the full-length NLRX1. Despite the lack of an N-terminal domain that exists in the full-length NLRX1, overexpression of NLRX1-tv4 still impaired fish IFN antiviral response and promoted viral replication in fish cells, similar to the full-length NLRX1. Mechanistically, NLRX1-tv4 targeted STING for proteasome-dependent protein degradation by recruiting an E3 ubiquitin ligase RNF5 to drive the K48-linked ubiquitination, eventually downregulating the IFN antiviral response. Mapping of NLRX1-tv4 domains showed that its N-terminal and C-terminal regions exhibited a similar potential to inhibit STING-mediated IFN antiviral response. Our findings reveal that like the full-length NLRX1, zebrafish NLRX-tv4 functions as an inhibitor to shape fish IFN antiviral response.IMPORTANCEIn this study, we demonstrate that a transcript variant of zebrafish NLRX1, termed NLRX1-tv4, downregulates fish IFN response and promotes virus replication by targeting STING for protein degradation and impairing the interaction of STING and TBK1 and that its N- and C-terminus exhibit a similar inhibitory potential. Our results are helpful in clarifying the current contradictory understanding of structure and function of vertebrate NLRX1s.

[Exploration of the diagnosis and treatment for benign prostatic hyperplasia with acupuncture based on jingjin theory]

Benign prostatic hyperplasia is caused by kidney deficiency and impaired qi transformation of the urinary bladder and is manifested by the stagnation of essence chamber. Based on jingjin (muscle region of meridian, sinew/fascia) theory and taking the visceral membrane as the principal, acupuncture is delivered at sinew/fascia to promote qi circulation, resolve stasis and open the orifice. Guided by CT, the needle is inserted at Zhongji (CV 3), the front-mu point of the urinary bladder, and then goes to the prostatic capsule, meaning "the disease of zang organ is treated by needling the front-mu point". In treatment of benign prostatic hyperplasia, this acupuncture therapy stimulates the different layers of fascia, by which, the defensive qi on the exterior is regulated and "essence orifice" in the interior is adjusted so that the urination can be promoted.

Idiopathic hypereosinophilic syndrome with hepatic sinusoidal obstruction syndrome: A case report and literature review

BACKGROUND

Hypereosinophilic syndrome (HES) is classified as primary, secondary or idiopathic. Idiopathic HES (IHES) has a variable clinical presentation and may involve multiple organs causing severe damage. Hepatic sinusoidal obstruction syndrome (HSOS) is characterized by damage to the endothelial cells of the hepatic sinusoids of the hepatic venules, with occlusion of the hepatic venules, and hepatocyte necrosis. We report a case of IHES with HSOS of uncertain etiology.

CASE SUMMARY

A 70-year-old male patient was admitted to our hospital with pruritus and a rash on the extremities for > 5 mo. He had previously undergone antiallergic treatment and herbal therapy in the local hospital, but the symptoms recurred. Relevant examinations were completed after admission. Bone marrow aspiration biopsy showed a significantly higher percentage of eosinophils (23%) with approximately normal morphology. Ultrasound-guided hepatic aspiration biopsy indicated HSOS. Contrast-enhanced computed tomography (CT) of the upper abdomen showed hepatic venule congestion with hydrothorax and ascites. The patient was initially diagnosed with IHES and hepatic venule occlusion. Prednisone, low molecular weight heparin and ursodeoxycholic acid were given for treatment, followed by discontinuation of low molecular weight heparin due to ecchymosis. Routine blood tests, biochemical tests, and imaging such as enhanced CT of the upper abdomen and pelvis were reviewed regularly.

CONCLUSION

Hypereosinophilia may play a facilitating role in the occurrence and development of HSOS.

Bioinformatics-based design of a fusion vaccine with CTLA-4 variable region to combat Brucella

Brucellosis has become a global zoonotic disease, seriously endangering the health of people all over the world. Vaccination is an effective strategy for protection against Brucella infection in livestock in developed countries. However, current vaccines are pathogenic to humans and pregnant animals, which limits their use. Therefore, it is very important to improve the safety and immune protection of Brucella vaccine. In this study, different bioinformatics approaches were carried out to predict the physicochemical properties, T/B epitope, and tertiary structure of Omp2b and Omp31. Then, these two proteins were sequentially linked, and the Cytotoxic T lymphocyte associated antigen-4 (CTLA-4) variable region was fused to the N-terminal of the epitope sequence. In addition, molecular docking was performed to show that the structure of the fusion protein vaccine had strong affinity with B7 (B7-1, B7-2). This study showed that the designed vaccine containing CTLA-4 had high potency against Brucella, which could provide a reference for the future development of efficient brucellosis vaccines.

Yellow catfish RIO kinases (RIOKs) negatively regulate fish interferon-mediated antiviral response

In mammals, right open reading frame kinases (RIOKs) are initially reported to participate in cancer cell proliferation, apoptosis, migration and invasion, and recently they have been related to host immune response. Little is known about the homologs of RIOKs in fish. In the current study, we cloned three homologous genes of RIOK family in yellow catfish (Pelteobagrus fulvidraco), termed Pfriok1, Pfriok2 and Pfriok3. Pfriok1, Pfriok2 and Pfriok3 were constitutively expressed at relatively high levels in yellow catfish tissues, and their mRNA levels were not changed under viral infection. Individual overexpression of PfRIOK1, PfRIOK2 and PfRIOK3 attenuated fish interferon (IFN) response, thereby promoting viral replication in fish cells. Mechanistically, yellow catfish RIOK proteins downregulated fish IFN response through attenuating TBK1 protein levels in cytoplasm. Our findings suggest that yellow catfish RIOK1, RIOK2 and RIOK3 are involved in downregulating fish IFN antiviral response.

[The role of cell division cycle 42 in root development of tooth and the involved mechanisms]

Objective: To explore the effect of cell division cycle 42 (CDC42) on root development and its regulation on cell proliferation and migration in Hertwig's epithelial root sheath (HERS). Methods: Trace the spatiotemporal expression of CDC42 in root development process [postnatal day 5 (P5), P7, P14] through immunofluorescence staining. Nine eight-week-old C57BL/6J male mice were randomly divided into 3 groups using a simple random sample method (n=3 in each group). P3 tooth germ was cultured in air-liquid system for 1 day and then transplanted to renal capsule each to observe tooth root development. The control group implanted tooth germ only. The phosphate buffered saline (PBS) group implanted tooth germ and gel beads soaked with PBS, while the ML141 group implanted tooth germ and gel beads soaked with CDC42 inhibitor (ML141). Cdc42 in HERS cells was inhibited via lentivirus transfection. Cell counting kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EdU) assay and scratch assay were performed. The distribution of Golgi apparatus (GM130) and cytoskeleton (F-actin) in migrated cells were mapped via immunofluorescence staining. Results: CDC42 was expressed in epithelial cells of HERS, polarized ameloblasts and odontoblasts, as well as adjacent dental papilla and dental follicle cells during tooth root development. The root length of the ML141 group [(0.61±0.09) mm] was substantially shorter than that of control group [(1.03±0.19) mm, P=0.007] and PBS group [(0.98±0.10) mm, P=0.021] according to the data of renal capsule transplantation. After lentiviral transfection, the relative expression of Cdc42 in knockdown group (0.31±0.33) was significantly lower than that in control group (1.05±0.08) (t=15.38, P<0.001), demonstrating the knockdown efficiency closed to 70%. Cell viabilities were significantly inhibited in knockdown group (0.87±0.04, 0.96±0.10, 0.59±0.06, respectively) compared with those in control group (1.09±0.13, 1.55±0.32, 1.10±0.09, respectively) after 3, 4 and 5 days (t=3.16, P=0.016; t=4.23, P=0.002; t=5.08, P<0.01), and the cell proliferation ability in knockdown group [(1.65±0.64)%] also decreased than that in the control group [(4.02±1.12)%](t=5.21, P<0.001). In addition, the cell migration rates after 24 and 48 h [(45.1±4.2)%, (56.4±8.3)%] in knockdown group were obviously lower than those in the control group [(63.8±7.4)%, (80.2±7.8)%] (t=3.78, P=0.019; t=3.62, P=0.023). After Cdc42 was knocked down, Golgi apparatus distributed along the nucleus while behaved oriented in the control group. Conclusions: CDC42 plays an important role in the regulation of root length during root development, which may mediate root elongation by affecting the migration and proliferation of HERS cells.

[Application characteristics of Qugu (CV 2) in ancient and modern literature]

To summarize and analyze the clinical application characteristics of Qugu (CV 2) in ancient and modern literature based on data mining technology. The Chinese Medical Code (the 5th edition) was taken as the retrieval source of ancient literature, while the CNKI, Wanfang, and VIP databases were taken as the retrieval source of modern literature. The indications of Qugu (CV 2) used alone or with compatible acupoints, compatible acupoints, acupuncture-moxibustion manipulation, etc., were systematically sorted out. As a result, a total of 140 articles of ancient literature were included. The common indications of Qugu (CV 2) used alone were urinary retention, profuse vaginal discharge and hernia. The common indications of Qugu (CV 2) used with compatible acupoints were profuse vaginal discharge, stranguria and hernia. Sixty-four acupoints were concurrently used with Qugu (CV 2), Qugu (CV 2) was mainly compatible with acupoints of conception vessel, bladder meridian and liver meridian, and the high-frequency acupoints included Zhongji (CV 3), Guanyuan (CV 4) and Sanyinjiao (SP 6); five-shu points were the most used special acupoints, and moxibustion therapy was often used. A total of 73 modern articles were included. The common indications of Qugu (CV 2) used alone were urinary retention, erectile dysfunction and chronic prostatitis; the common indications of Qugu (CV 2) used with compatible scupoints were urinary retention, erectile dysfunction and prostatic hyperplasia. Thirty-six acupoints were concurrently used with Qugu (CV 2), Qugu (CV 2) was mainly compatible with acupoints of conception vessel, kidney meridian and spleen meridian, and the high-frequency acupoints included Zhongji (CV 3), Guanyuan (CV 4) and Zusanli (ST 36); front-mu points were the most used special acupoints, and acupuncture therapy was often used. Qugu (CV 2) treats a wide range of diseases in ancient times, the distant treatment effectiveness of acupoints is emphasized; and it mainly treats local diseases in modern times, the nearby treatment effectiveness of acupoints is emphasized.

Zebrafish MARCH8 downregulates fish IFN response by targeting MITA and TBK1 for protein degradation

Recent studies have related the membrane-associated RING-CH-type finger (MARCH) family proteins to host innate immune response. Zebrafish (Danio rerio) MARCH8 is reported to target SVCV glycoprotein for degradation; however, little is known about whether fish MARCH8 is involved in innate interferon (IFN) response. In this study, zebrafish march8 was significantly induced by SVCV infection. Overexpression of MARCH8 diminished fish IFN-mediated antiviral response, thus promoting the replication of SVCV and GCRV in fish cells. Mechanistically, MARCH8 interacts with and degrades MITA and TBK1 proteins to inhibit IFN response. Moreover, MARCH8 has an E3 ligase activity and enhances MITA and TBK1 polyubiquitination. Our findings reveal a mechanism whereby zebrafish MARCH8 downregulates fish IFN response and facilitates viral replication by targeting MITA and TBK1 for protein degradation.

[A retrospective controlled study of TACE-HAIC-targeted-immune quadruple therapy for intermediate and advanced-stage hepatocellular carcinoma]

Objective: To evaluate the efficacy and safety of transcatheter arterial chemoembolization (TACE)-hepatic arterial infusion chemotherapy (HAIC)-targeted-immune quadruple therapy in patients with intermediate and advanced-stage hepatocellular carcinoma (HCC). Methods: 101 patients with intermediate and advanced stage HCC were enrolled according to the inclusion and exclusion criteria, and then they were divided into a combination group and a control group. Patients in the combination group was treated with TACE-HAIC-targeted-immune quadruple therapy, while the control group was only treated with TACE therapy. The overall survival (OS), progression-free survival (PFS), and treatment-related adverse reactions were statistically analyzed in the two groups of patients. Statistical analysis was carried out by t-test, χ² test, rank sum test, Kaplan-Meier curve, log-rank test, Cox regression (or proportional hazards model) analysis according to different data. Results: The tumor objective response rate and disease control rate as evaluated by mRECIST 1.1 criteria in the combination group were 80% and 94%, respectively, which were significantly higher than those in the control group, 41.2% (P<0.001) and 74.5% (P=0.007). The OS and PFS of the combination group were 15.6 months [95%CI 11.3-NA ] and 8.8 months [95%CI 6.9-12.0], respectively, which were significantly better than the control group at 6.1 months [95%CI 5.3-6.6] (P<0.001) and 3.2 months [95%CI 3.0-3.6] (P<0.001). Gastric ulcer incidence was significantly higher in the combination group (9/50, 18%) than that in the control group (2/51, 3.9%) (P=0.023). Conclusion TACE-HAIC-targeted-immune quadruple therapy is a more effective treatment mode for intermediate and advanced-stage HCC than TACE alone, and attention should be paid to the monitoring of target immune-related adverse reactions.

[Percutaneous biliary stent combined with brachytherapy for malignant obstructive jaundice: a multicenter retrospective controlled study]

Objective: To investigate the efficacy, safety and prognostic factors of percutaneous biliary stent combined with iodine-125 seed chain brachytherapy (radiotherapy) in the treatment of malignant obstructive jaundice. Methods: Data of 107 cases with malignant obstructive jaundice treated with percutaneous biliary stent implantation from January 2017 to December 2020 were retrospectively analyzed. Among them, 58 cases received biliary stent combined with iodne-125 seed chain brachytherapy (study group), and 49 cases received biliary stent implantation (control group). The changes of bilirubin, stent patency time, complications, overall survival (OS) and prognostic factors were analyzed in both groups. Results: The incidence of complications in the study group and the control group were 17.2% and 18.3% respectively, and the difference was not statistically significant (P=0.974). Serum total bilirubin levels were decreased significantly in both groups at one month after surgery (P<0.001). Postoperative stent patency time was significantly better in the study group (10.0±1.6 months) (95% CI: 8.2～12.5) than that in the control group (5.2±0.4 months) (95% CI: 4.1～6.0, P<0.001). The median OS was longer in the study group (11.2±1.8 months) (95% CI: 9.2～12.8) than that in the control group (8.0±1.1 months) (95% CI: 8.0～12.8, P<0.001). Multivariate analysis result showed that stent combined with brachytherapy (HR=0.08, 95% CI:0.04～0.15, P<0.001) and receiving further anti-tumor therapy after surgery (HR=0.27, 95% CI:0.15~0.49, P<0.001) were independent risk factors affecting the patency of biliary stents. Preoperative percutaneous transhepatic biliary drainage (HR=0.46, 95%CI:0.28～0.74, P=0.002), stent combined with brachytherapy (HR=0.23, 95%CI:0.14～0.39, P<0.001) and receiving further anti-tumor therapy after surgery (HR=0.37, 95%CI:0.22～0.61, P<0.001) were independent risk factors affecting OS. Conclusion: Percutaneous biliary stent combined with brachytherapy is safe and effective in the treatment of malignant obstructive jaundice, which can significantly prolong the patency time of biliary stent and the survival time of patients.

[Status of HVPG clinical application in China in 2021]

Objective: The investigation and research on the application status of Hepatic Venous Pressure Gradient (HVPG) is very important to understand the real situation and future development of this technology in China. Methods: This study comprehensively investigated the basic situation of HVPG technology in China, including hospital distribution, hospital level, annual number of cases, catheters used, average cost, indications and existing problems. Results: According to the survey, there were 70 hospitals in China carrying out HVPG technology in 2021, distributed in 28 provinces (autonomous regions and municipalities directly under the central Government). A total of 4 398 cases of HVPG were performed in all the surveyed hospitals in 2021, of which 2 291 cases (52.1%) were tested by HVPG alone. The average cost of HVPG detection was (5 617.2±2 079.4) yuan. 96.3% of the teams completed HVPG detection with balloon method, and most of the teams used thrombectomy balloon catheter (80.3%). Conclusion: Through this investigation, the status of domestic clinical application of HVPG has been clarified, and it has been confirmed that many domestic medical institutions have mastered this technology, but it still needs to continue to promote and popularize HVPG technology in the future.

[Safety and efficacy of TIPS combined with iodine-125 seed strands in the treatment of patients with hepatocellular carcinoma combined with portal vein tumor thrombosis]

Objective: To study the safety and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) combined with iodine-125 (¹²⁵Ⅰ) seed strands implantation in patients with hepatocellular carcinoma combined with portal vein tumor thrombosis. Methods: 25 cases with diffuse intrahepatic tumor combined with tumor thrombus type Ⅲ/Ⅳ requiring TIPS were simultaneously implanted with ¹²⁵Ⅰseed strand. Tumor thrombus was controlled with ¹²⁵I seed implantation brachytherapy to keep the TIPS pathway unobstructed, reduce the portal vein pressure, and observe the changes in the cause of death of the patients. During the same period, 30 cases without TIPS and seed strand implantation were used as controls. Data between groups were compared using t-test, Chi-Squared test or Fisher's exact test. Results: TIPS combined with ¹²⁵Ⅰ seed strand implantation was safe in patients with diffuse hepatocellular carcinoma combined with type III/IV portal vein tumor thrombus, and 92.0% (23/25) of the patients maintained unobstructed TIPS pathway. Compared with the control group, patients in the treatment group died of fewer lead-related complications, and most died from chronic liver failure (84.0% vs. 56.7%, χ² = 4.771, P=0.029). The incidence of upper gastrointestinal bleeding was significantly decreased (12.0% vs. 46.7%, χ² =7.674, P=0.006) and ascites severity was significantly improved (mild 40.0% vs. 16.7%, moderate 52.0% vs. 20.0%, severe 8.0% vs. 46.7%, χ² =13.246 , P=0.001). Conclusions: TIPS combined with ¹²⁵Ⅰ seed strand implantation is safe and feasible in patients with diffuse intrahepatic tumor combined with tumor thrombus type Ⅲ/Ⅳ. Moreover, it can effectively keep the shunt patency and reduce portal vein pressure, thereby reducing the incidence of upper gastrointestinal bleeding and improving the degree of ascites. TIPS combined with ¹²⁵Ⅰ seed strand implantation may be used as a standard treatment modality for patients requiring TIPS therapy combined with tumor thrombus type Ⅲ/Ⅳ.

[Risk factors of tracheal extubation failure in children with spinal muscular atrophy combined with pneumonia]

Objective: To summarize the risk factors of tracheal extubation failure in children with spinal muscular atrophy (SMA) combined with pneumonia. Methods: In this retrospective study, clinical data of 34 children with SMA combined with pneumonia who were hospitalized in Children's Hospital Affiliated to Capital Institute of Pediatrics from August 2018 to December 2021 were analyzed. According to whether the extubation was successful or not, they were divided into the success group and the failure group. The risk factors that may affect the success of extubation between two groups were derived by comparing the clinical characteristics by Mann-Whitney U test and Chi-square test, followed by multivariate Logistic regression. Results: Among the 34 cases, there were 14 males and 20 females, aged 10.8 (6.0,25.2) months at the time of hospitalization, 31 cases were type 1 SMA and 3 cases were type 2. Eleven children were unable to eat independently before intubation, 22 were treated with airway clearance techniques and 28 had multiple pulmonary infections. There were 21 cases in the success group and 13 cases in the failure group. The failure group had higher maximum partial pressure of arterial carbon dioxide level during intubation and higher rate of consolidation changes in chest images before extubation (81 (49,86) vs. 48 (43,56) mmHg (1 mmHg=0.133 kPa), 6/13 vs. 10%(2/21), Z=-2.55, χ²=5.99, both P<0.05). Multivariate Logistic regression analysis showed that tube feeding before intubation (OR =39.88, 95%CI 3.36-473.29, P=0.003) and not receiving airway clearance therapy (OR =14.55, 95%CI 1.35-156.78, P=0.027) were independent risk factors for extubation failure. Conclusions: The independent risk factors of tracheal extubation failure in children with SMA combined with pneumonia are unable to eat independently before intubation and not receiving airway clearance therapy. Therefore, the conditions to improve the success of extubation consist of having the ability to eat independently before intubation, using airway clearance techniques to improve ventilation and to make the chest images as clear as possible.

Promoter Binding and Nuclear Retention Features of Zebrafish IRF Family Members in IFN Response

Interferon regulatory factors (IRFs) constitute a family of transcription factors that synchronize interferon (IFN) antiviral response through translocating to nucleus and binding to the promoters of IFN and IFN-stimulated genes (ISGs). Fish contain 11 IRF members; however, whether or how fish IRF family genes function in IFN response remains limited. Herein, we determine the regulatory roles of 11 zebrafish IRF family members in IFN response relevant to their subcellular localization and promoter binding. Zebrafish IRF family members display three patterns of constitutive localization, only in nucleus (IRF1/2/9/11), only in cytoplasm (IRF3/5/7), and largely in nucleus with small amounts in cytoplasm (IRF4b/6/8/10). DNA pull-down assays confirm that all zebrafish IRF proteins are capable to bind fish IFN promoters, albeit to various degrees, thus regulating IFN gene transcription as activators (IRF1/3/5/6/7/8/9/11) or repressors (IRF2/4b/10). Further characterization of distinct IFN gene activation reveals that IRF1/3/5/6/7/8/9/11 efficiently stimulate zebrafish IFNφ1 expression, and IRF1/7/11 are responsible for zebrafish IFNφ3 expression. Two conserved basic residues within the helix α3 of DNA binding domains (DBDs) contribute to constitutive or inducible nuclear import for all zebrafish IRF family members and DNA binding for most members, thereby enabling them to function as transcription factors. Our results reveal a conserved and general mechanism that specifies zebrafish IRF family proteins to nuclear import and DNA binding, thereby regulating fish IFN response.

Discovery of a potent BTK and IKZF1/3 triple degrader through reversible covalent BTK PROTAC development

Building on our previous work on ibrutinib-based reversible covalent Bruton's tyrosine kinase (BTK) PROTACs, we explored a different irreversible BTK inhibitor poseltinib as the BTK binder for PROTAC development. Different from ibrutinib, converting the irreversible cysteine reacting acrylamide group of poseltinib to a reversible covalent cyano-acrylamide group dramatically decreases the binding affinity to BTK by over 700 folds. Interestingly, one of the reversible covalent BTK PROTACs based on poseltinib with a rigid linker, dubbed as PS-RC-1, is highly potent (IC₅₀ = ~10 nM) in Mino cells but not in other mantle cell lymphoma (MCL) cell lines, such as Jeko-1 and Rec-R cells. We showed that PS-RC-1 potently induces degradation of IKZF1 and IKZF3 but not BTK or GSPT1, accounting for its toxicity in Mino cells. We further decreased the molecular size of PS-RC-1 by shrinking the BTK binding moiety and developed PS-2 as a potent BTK and IKZF1/3 triple degrader with high specificity.

Enhancing intracellular accumulation and target engagement of PROTACs with reversible covalent chemistry

Current efforts in the proteolysis targeting chimera (PROTAC) field mostly focus on choosing an appropriate E3 ligase for the target protein, improving the binding affinities towards the target protein and the E3 ligase, and optimizing the PROTAC linker. However, due to the large molecular weights of PROTACs, their cellular uptake remains an issue. Through comparing how different warhead chemistry, reversible noncovalent (RNC), reversible covalent (RC), and irreversible covalent (IRC) binders, affects the degradation of Bruton's Tyrosine Kinase (BTK), we serendipitously discover that cyano-acrylamide-based reversible covalent chemistry can significantly enhance the intracellular accumulation and target engagement of PROTACs and develop RC-1 as a reversible covalent BTK PROTAC with a high target occupancy as its corresponding kinase inhibitor and effectiveness as a dual functional inhibitor and degrader, a different mechanism-of-action for PROTACs. Importantly, this reversible covalent strategy is generalizable to improve other PROTACs, opening a path to enhance PROTAC efficacy.

[Management strategy for the resumption of regular diagnosis and treatment in gastrointestinal surgery department during the outbreak of coronavirus disease 2019 (COVID-19)]

Acute abdomen, abdominal trauma, gastrointestinal bleeding and gastrointestinal tumors are the main conditions that are routinely treated in gastrointestinal surgery department with high incidence and critical condition. These conditions need emergency or selective operations. During the outbreak of the coronavirus disease 2019 (COVID-19), it's a great challenge for us to meet the patients' requirement under the situation. As the COVID-19 was brought under control in China, the Department of General Surgery in Nanfang Hospital resumed regular medical services gradually. Based on our clinical practice, the four major measures of strengthening pre-hospital screening, perioperative prevention and control, medical staff protection, and ward management were adopted. These main measures include the strict implementation of the appointment system and triage system before admission; the conduction of epidemiological and preliminary screening of viral nucleic acids; the chest CT examination during the perioperative period to re-screen COVID-19; the reduction of the risk of droplets and aerosol transmission; the minimally invasive surgery combined with enhanced recovery program in order to reduce patient's susceptibility and shorten the length of postoperative hospital stay; the reinforcement of specific infection control training for medical staff; the strict implementation of hierarchical protection; the establishment of gastrointestinal surgery prevention and control system; the rehearsal of emergency exercise; the installation of quarantine wards; the screening and management of family care-givers; the strict disinfection of environment and materials. Our preliminary practice shows that following the work guidelines issued by the Guangdong Province COVID-19 Prevention and Control Office and adopting precise management strategies in combination with the specific clinical features of gastrointestinal surgery, it is possible to safely resume regular care for the patients and comply to epidemic control at the same time.

[Clinical characteristics of non-invasive ventilation treatment in children with spinal muscular atrophy and sleep disordered breathing]

Objective: To study the short-term and long-term efficacy of the non-invasive ventilation treatment in children with spinal muscular atrophy (SMA) and sleep-disordered breathing. Methods: This was a prospective research to study the effect of night-time non-invasive ventilation in children with SMA and moderate to severe sleep-disordered breathing during March 2016 to January 2018, from the Pulmonary Department of Capital Institute of Pediatrics Affiliated Children's Hospital. Patients were divided into the treated group (with night-time non-invasive ventilation) and the control group (without ventilator). Sleep breathing pressure titration was suggested to the patients who were prepared to receive non-invasive ventilation. All cases were followed up for one year. Parameters'changes in polysomnography were assessed (paired t-test) in titration patients. Frequency of respiratory tract infection during the next year in the patients with and without ventilation was collected and compared (Mann-Whitney U-test). Results: Seventeen cases were recruited. The average age was (5.1±2.9) years, 10 cases were boys and 7 cases were girls. In the titration group (8 patients), after non-invasive ventilation, the average apnea hypopnea index was (3.8±2.5) times/h (t=4.086, P=0.005), hypopnea index was (2.4±1.2) times/h (t=2.779, P=0.027), average oxygen saturation during total sleep time was 0.966±0.007 (t=-5.292, P=0.001), and the minimum oxygen saturation was 0.906±0.023 (t=-3.938, P=0.006). All the above parameters were significantly improved after treatment. Than before, which was (16.6±9.7) times/h, (7.2±4.7) times/h, 0.946±0.015, 0.786±0.092 respectively. Ventilator mode for the 9 children with long time non-invasive ventilation at home was Bi-level positive airway pressure S/T. The positive airway pressure was set at 8-14 cmH(2)O (1 cmH(2)O=0.098 kPa) in inspiratory phase and 4-6 cmH(2)O in expiratory phase. In the treated group (9 patients), the average frequency of upper respiratory tract infection was 1.0 (0, 3.0) times/year (Z=-2.245, P=0.023), the lower respiratory tract infection was 0 (0, 0) times/year (Z=-3.189, P=0.001), hospitalization was 0 (0, 0) times/year (Z=-3.420, P<0.01), and admission to intensive care unit was 0 (0, 0) times/year (Z=-3.353, P=0.029). All the above indexes were significantly decreased compared with the control group (8 patients), which was 3.0 (2.3, 7.0) times/year, 2.0 (1.3, 4.5) times/year, 1.0 (1.0, 4.3) times/year, 0.5 (0, 1.0) times/year respectively. Conclusion: Non-invasive ventilation is efficient to SMA children with sleep-disordered breathing, and also can reduce the incidence of respiratory tract infections for children with SMA.

[Effects of PNPLA3, TM6SF2 gene polymorphisms and its interactions with smoking and alcohol drinking on hepatitis B virus-associated hepatocellular carcinoma]

Objective: To explore the SNP effects of patatin-like phospholipase domain which containing 3 (PNPLA3), transmembrane 6 superfamily member 2 (TM6SF2) gene, environmental effects of smoking, alcohol drinking and interaction between gene-gene, gene-environment and drinking-smoking on hepatitis B virus-associated hepatocellular carcinoma (HBV-HCC). Methods: We collected anticoagulant peripheral blood from patients of HBV-HCC, chronic hepatitis B (CHB), liver cirrhosis (LC) and from healthy controls to detect the single nucleotide polymorphism (SNP) of patatin-like phospholipase domain containing 3 (PNPLA3) gene loci rs738409 and transmembrane 6 superfamily member 2 (TM6SF2) gene loci rs58542926, using the flight mass spectrometry method. The optimal assignment value of gene polymorphisms was defined by using the online SNP stats. Hardy-Weinberg (H-W) balance was tested for SNP. Effects of the genetic and environmental factors to HBV-HCC were analyzed by using the multiple classification logistic regression method. The gene-gene, gene-smoking and alcohol drinking interaction effects were investigated by Fork-Life analysis and binary logistic regression methods. Results: The frequency distribution of CHB group rs738409 loci seemed not in conformity with the H-W balance (χ(2)=11.980, P<0.005). Two loci frequency distributions in the other groups were all in accordandce with the H-W balance. After adjusting for influences on age and sex and comparing to the healthy group, the rs58542926 mutation appeared as OR=1.659, 95%CI: 1.026-2.684, P=0.039, in the HBV-HCC group. When comparing to CHB group, the HBV-HCC group presented that drinking as OR=1.680, 95%CI: 1.121-2.519, P=0.012. When comparing to the LC group, the ORs of drinking and smoking were 1.539 (1.071-2.213) and 1.453 (1.005-2.099) respectively, in the HBV-HCC group. When comparing to the CHB+LC group, interactions between the HBV-HCC group were found rs738409 and rs58542926 on additive model OR=1.548 (U=1.885, P=0.029) and OR=1.658 (P=0.024) on logistic regression model while drinking was rs738409 on interaction additive model with OR=1.811(U=1.965, P=0.024). As for drinking and mutation of rs738409, the multiplication model of logistic regression showed no statistically significant differences. Interaction between smoking and drinking appeared as OR=1.756 (P<0.001) in the logistics regression multiplication model. Conclusions: Factors as mutation of TM6SF2, smoking and drinking all appeared as risk factors for HBV-HCC. Mutations of both PNPLA3 and TM6SF2, together with smoking and drinking all served as risk factors for HBV-HCC. However, the mutation of single PNPLA3 appeared as a protective factor on HBV-HCC.

[Expression of Fermintin family homologous protein 2 in non-small cell lung cancer and its clinical significance]

Objective: To investigate the expression of Fermintin family homologous protein 2 (FERMT2) in non-small cell lung cancer and its clinical significance. Methods: Seventy-two patients with non-small cell lung cancer were collected at Xinxiang Central Hospital, Henan Province, from January 2015 to January 2017.There were 48 male and 24 female patients, the age ranged from 37 to 78 years (mean 58 years). The expression of FERMT2 in tumor samples and para-cancerous tissues were detected by immunohistochemistry. Protein and mRNA expression of FERMT2 were detected by Western blot and real-time fluorescence quantitative PCR, respectively. Western blot method was also used to detect integrin-related protein expression, including integrin beta 1 (CD29), vascular cell adhesion molecule (VCAM1), and mobile related protein-1 (MRP1). Results: Immunohistochemistry showed that the positive rates of FERMT2 expression were 81.9%(59/72)in carcinoma tissue and 15.4%(11/72) in para-cancerous tissues, and the difference was statistically significant (P<0.01). Positive FERMT2 expression was different in tumors at different tumor stages: 11/17 at stage Ⅰ, 16/20(80.0%)at stage Ⅱ, 17/20(85.0%)at stage Ⅲ, and 15/15 at stage Ⅳ, and there was a significant difference between each stage (P<0.01). By real-time PCR and Western blot, the expression of FERMT2 in non-small cell lung cancer tissues was significantly higher than that of para-cancerous tissue (P<0.01). The expression levels of integrin related proteins (integrin β1, VCAM1 and MRP1) in tumor tissues were significantly higher than those in para-cancerous tissues, and positively correlated with the expression of FERMT2 (r=0.531, P<0.01; r=0.483, P<0.01; r=0.612, P<0.01). Conclusions: FERMT2 is highly expressed in non-small cell lung carcinomas. Its expression is closely correlated with the tumor clinical stage. It is hypothesized that FERMT2 may promote tumor metastasis through interactions with integrin-like protein.

Difluoromethylation of (hetero)aryl chlorides with chlorodifluoromethane catalyzed by nickel

Relatively low reactivity hinders using chlorodifluoromethane (ClCF₂H) for general difluoromethylation with organic molecules, despite its availability as an inexpensive industrial chemical. To date, transformations of ClCF₂H are very limited and most of them involve difluorocarbene intermediate. Here, we describe a strategy for difluoromethylation of aromatics through nickel-catalyzed cross-coupling of ClCF₂H with readily accessible (hetero)aryl chlorides. The reaction proceeds under mild reaction conditions with high efficiency and features synthetic simplicity without preformation of arylmetals and broad substrate scope, including a variety of heteroaromatics and commercially available pharmaceuticals. The reliable practicability and scalability of the current nickel-catalyzed process has also been demonstrated by several 10-g scale reactions without loss of reaction efficiency. Preliminary mechanistic studies reveal that the reaction starts from the oxidative addition of aryl chlorides to Ni(0) and a difluoromethyl radical is involved in the reaction, providing a route for applications of ClCF₂H in organic synthesis and related chemistry.

Intra-arterial ethanol embolization augments response to TACE for treatment of HCC with portal venous tumor thrombus

Background

The prognosis of hepatocellular carcinoma with portal vein tumor thrombus remains extremely poor. This pilot study aimed to evaluate the technical feasibility, effectiveness and safety of transcatheter chemoembolization for tumors in the liver parenchyma plus intra-arterial ethanol embolization for portal vein tumor thrombus.

Methods

A pilot study was carried out on 31 patients in the treatment group (transcatheter chemoembolization plus intra-arterial ethanol embolization) and 57 patients in the control group (transcatheter chemoembolization alone). Enhanced computed tomography/magnetic resonance images were repeated 4 weeks after the procedure to assess the response. Overall survival and complications were assessed until the patient died or was lost to follow-up.

Results

Median survival was 10.5 months in the treatment group (2.4 ± 1.7 courses) and 3.9 months in the control group (1.9 ± 1 courses) (P = 0.001). Patients in the treatment group had better overall survival (at 3, 6 and 12 months, respectively), compared to patients in the control group (90.3% vs. 59.6%, 64.5% vs. 29.8%, and 41.9% vs. 10.6%; p = 0.001). Furthermore, the rate of portal vein tumor thrombus regression was higher in the treatment group (93.1%) than in the control group (32.1%) (P < 0.001).

Conclusions

Based on the results of this study, transcatheter chemoembolization combined with intra-arterial ethanol embolization may be more effective than transcatheter chemoembolization alone for treating hepatocellular carcinoma with portal vein tumor thrombus. Intra-arterial ethanol embolization for treating portal vein tumor thrombus is safe, feasible and prolongs overall survival.

A genetic variant in long non-coding RNA MALAT1 associated with survival outcome among patients with advanced lung adenocarcinoma: a survival cohort analysis

Background

Recently studies have demonstrated that the long non-coding RNA (lncRNA) metastasis associated lung adenocarcinoma transcript 1 (MALAT1) may participate in the development and progression of lung cancer. In this study, we hypothesized that genetic variant of this lncRNA may affect the prognosis of lung cancer patients.

Methods

We conducted a follow-up study for 538 patients with non–small cell lung carcinoma (NSCLC), including 140 early-staged (stage I and II) and 398 advanced staged (stage III and IV) patients. The genetic variant rs3200401 in MALAT1 was then genotyped among this population by using TaqMan assay. The association of this variant with overall survival of these patients was further analyzed.

Results

It was shown that among the advanced lung adenoma patients, subjects carrying rs3200401 CT and CT + TT genotypes had significantly longer median survival time (MST = 29.9, 28.9 vs. 19.3 month, Long-rank P = 0.019 and 0.024, respectively) and decreased death risks [crude HR (95% CI) = 0.65 (0.43–0.98) and 0.64 (0.44–0.95), P = 0.040 and 0.025, respectively], when compared to subjects wtih the MALAT1 rs3200401 CC genotype. However, the beneficial effect of rs3200401 was not seen among early NSCLC and advanced lung squamous cell carcinoma patients. We further tested the TCGA data, and found that a higher expression of MALAT1 was associated with metastatic of advanced lung adenocarcinoma but not with lung squamous cell carcinoma.

Conclusions

The rs3200401 T allele located on the lncRNA MALAT1 was associated with a better survival for advanced lung adenocarcinoma patients, which may offer a novel prognostic biomarker for this patient subgroup. However, these results need to be validated in larger populations of lung cancer and the biological function of this variant still warrants further investigation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3151-6) contains supplementary material, which is available to authorized users.

CT-guided 125I seed implantation for inoperable retroperitoneal sarcoma: A technique for delivery of local tumor brachytherapy

Radical surgery is currently the first treatment of choice for retroperitoneal soft tissue sarcoma (RSTS). However, the prognosis of RSTS remains poor due to ineffective local control and a high incidence of metastasis after surgical resection. Brachytherapy has been shown to safely provide local radiotherapy for numerous types of cancer when used alone or in combination with surgical resection, but has not been well characterized in the management of RSTS. The aim of this study was to evaluate CT-guided 125I seed implantation for local control and pain relief in the treatment of inoperable RSTS. A total of 23 patients with RSTS were treated with 125I implantation. Pain was assessed using a visual analog scale. Other endpoints were evaluated via computed tomography scan or phone call/e-mail records. The occurrence of complications was assessed preoperatively (baseline) and during postoperatively follow-up or until patient succumbed. All patients were successfully treated with 125I implantation. A mean number of 70.87 radioactive seeds were applied in each patient. During the follow-up, two patients were unaccounted for, local recurrence occurred in three patients, five succumbed and complications were observed in sixteen. The patient's VAS score changed from 7.4 preoperatively to 7.6, 2.3, 2.0, 1.2, 1.5, 1.4 and 2.5 at 24 h, 1, 3, 6, 12, 24 and 36 months after the procedure, respectively. Good local control and significant pain relief after 125I seed implantation was observed in patients with inoperable RSTS. Thus, the present results suggest that this method could be an effective treatment option for patients with inoperable RSTS.

CT-guided biopsy for Langerhans cell histiocytosis of the atlas: a case report and literature review

Langerhans cell histiocytosis (LCH) is a rare disease, and involvement of the atlas is extremely uncommon. Biopsy of atlas lesions is difficult and risky. In this case report, we describe the performance of percutaneous computed tomography-guided biopsy of an atlantal LCH in a patient with no complication.

Hypoxia-induced apoptosis and mitochondrial dysfunction in chondrocytes arising from CREB phosphorylation reduction

Chondrocytes, which are embedded within the growth-plate or the intervertebral disc, are sensitive to environmental stresses, such as inflammation and hypoxia. However, little is known about the molecular signaling pathways underlying hypoxia-induced mitochondrial dysfunction and apoptosis in chondrocytes. We first examined the apoptosis, caspase-3 activity, and apoptosis-associated markers in human chondrocyte cell line C28/I2 under normoxia or hypoxia. We then investigated mitochondrial dysfunction and the activation of cyclic adenosine monophosphate response element-binding protein (CREB) signaling in the same human chondrocyte cell line. Our results indicated that hypoxia induced apoptosis and reduced CREB phosphorylation in chondrocytes. Upregulated mitochondrial superoxide and reactive oxygen species levels, and reduced mitochondrial membrane potential and complex IV activity were observed in hypoxia-treated C28/I2 cells. In conclusion, the present study confirmed reduced CREB phosphorylation, apoptosis induction, and mitochondrial dysfunction in the hypoxia-treated chondrocyte cells. This implies the key role played by CREB signaling in hypoxia-induced mitochondrial dysfunction and apoptosis in chondrocytes.

Synthesis of diaryldifluoromethanes by Pd-catalyzed difluoroalkylation of arylboronic acids

The first example of Pd-catalyzed aryldifluoromethylation of arylboronic acids with readily available aryldifluoromethyl bromides has been described. Preliminary mechanistic studies revealed that a Pd(0)L_n-initiated single electron transfer (SET) pathway is involved in the catalytic cycle.

Targeting pyruvate kinase M2 contributes to radiosensitivity of non-small cell lung cancer cells in vitro and in vivo

Aerobic glycolysis, a metabolic hallmark of cancer, is associated with radioresistance in non-small cell lung cancer (NSCLC). Pyruvate kinase M2 isoform (PKM2), a key regulator of glycolysis, is expressed exclusively in cancers. However, the impact of PKM2 silencing on the radiosensitivity of NSCLC has not been explored. Here, we show a plasmid of shRNA-PKM2 for expressing a short hairpin RNA targeting PKM2 (pshRNA-PKM2) and demonstrate that treatment with pshRNA-PKM2 effectively inhibits PKM2 expression in NSCLC cell lines and xenografts. Silencing of PKM2 expression enhanced ionizing radiation (IR)-induced apoptosis and autophagy in vitro and in vivo, accompanied by inhibiting AKT and PDK1 phosphorylation, but enhanced ERK and GSK3β phosphorylation. These results demonstrated that knockdown of PKM2 expression enhances the radiosensitivity of NSCLC cell lines and xenografts as well as may aid in the design of new therapies for the treatment of NSCLC.

Nickel-catalyzed cross-coupling of functionalized difluoromethyl bromides and chlorides with aryl boronic acids: a general method for difluoroalkylated arenes

Transition-metal-catalyzed difluoroalkylation of aromatics remains challenging despite the importance of difluoroalkylated arenes in medicinal chemistry. Herein, the first successful example of nickel-catalyzed difluoroalkylation of aryl boronic acids is described. The reaction allows access to a variety of functionalized difluoromethyl bromides and chlorides, and paves the way to highly cost-efficient synthesis of a wide range of difluoroalkylated arenes. The notable features of this protocol are its high generality, excellent functional-group compatibility, low-cost nickel-catalyst, and practicality for gram-scale production, thus providing a facile method for applications in drug discovery and development.

Highly selective gem-difluoroallylation of organoborons with bromodifluoromethylated alkenes catalyzed by palladium

A first example of Pd-catalyzed gem-difluoroallylation of organoborons using 3-bromo-3,3-difluoropropene (BDFP) in high efficiency with high α/γ-substitution regioselectivity has been developed. The reaction can also be extended to substituted BDFPs and has advantages of low catalyst loading (0.8 to 0.01 mol %), broad substrate scope, and excellent functional group compatibility, thus providing a facile route for practical application in drug discovery and development.

Rapid increase of serum neuron specific enolase level and tachyphylaxis of EGFR-tyrosine kinase inhibitor indicate small cell lung cancer transformation from EGFR positive lung adenocarcinoma?

We report the case of an 80-year-old male with relapsed EGFR exon 19 deletion lung adenocarcinoma treated with EGFR-tyrosine kinase inhibitor (TKI), but with poor response and rapid increase of serum neuron specific enolase (NSE). Repeat biopsy identified pathological transformation to small cell lung cancers (SCLC) retaining the same EGFR mutation. This case highlights routine serological testing of NSE may benefit for the lung adenocarcinoma patients resistant to TKIs.

Enhanced radioresponse with a novel recombinant human endostatin protein via tumor vasculature remodeling: experimental and clinical evidence

PURPOSE

This study aimed to examine the effect of the novel recombinant human endostatin (rh-Endo) protein on tumor vasculature, and to explore and evaluate the optimal scheduling of rh-Endo and radiotherapy (RT).

METHODS

Tumor-perfusion parameters and hypoxia were monitored after rh-Endo treatment in 10 non-small cell lung-cancer (NSCLC) patients. Eight-week female C57BL/6J mice were randomized to receive rh-Endo or control (saline) once daily for 12 days when Lewis lung carcinoma (LLC) reached approximately 100-150 mm(3). On planned days, tumors were measured for cell apoptosis, microvessel density, pericytes, blood-vessel morphology, and tumor hypoxia. The tumor response under different combinations of rh-Endo and RT schedules was evaluated.

RESULTS

Tumor hypoxia was significantly reduced 5 days after rh-Endo in NSCLC patients, and a similar result was found in the LLC mouse model. The anti-tumor effect was markedly enhanced when RT was administered within the remodeling period compared to any other treatment schedule. rh-Endo treatment remodeled the tumor vasculature after 5 days by reducing microvessel density and increasing pericytic coverage of the vessel endothelium.

CONCLUSION

This study demonstrated decreased hypoxia in animals and patients upon rh-Endo treatment, which also enhanced the radioresponse within the vasculature-remodeling period. The optimal clinical combination of rh-Endo and RT warrants further investigation.

CT-guided percutaneous vertebroplasty of the upper cervical spine via a translateral approach

BACKGROUND

The clinical management of spinal hemangiomas and osteolytic metastases involving the upper cervical spine (C1-C3) is challenging. Symptoms vary from simple vertebral pain to progressive neurological deficits. Surgery and radiotherapy have been the treatment options for years. Surgery, however, can result in complications, such as hemorrhage, and may be counter-indicated when the treatment goal is primarily palliative due to multiple metastases, an unfavorable prognosis and/or a poor performance state. On the other hand, radiotherapy carries the risk of inducing secondary sarcomas or producing radionecrosis. Percutaneous vertebroplasty (PVP) was recently introduced as an alternative for treating patients in whom surgery and radiotherapy are counter-indicated. As of yet, there are few PVP case reports.

OBJECTIVE

This study aimed to evaluate the safety and efficacy of PVP using a computed tomography (CT)-guided translateral approach via the space between the carotid sheath and vertebral artery for hemangiomas or metastatic lesions at C1-C3 under local anesthesia.

STUDY DESIGN

CT-guided PVP was performed in 15 patients with hemangiomas or metastatic lesions at C1-C3 and clinical outcomes were evaluated.

SETTING

An interventional therapy group at a medical center in a major Chinese city.

METHODS

Fifteen consecutive patients had a total of 15 cervical vertebral bodies treated with CT-guided PVP via a translateral approach. The patients were followed up for a mean postoperative period of 8.3 months (range, 1-40 months). Pain status was assessed using a visual analog scale (VAS). The presence of complications was assessed preoperatively (baseline) and at 24 hours, 2 weeks, and one, 3, 6, 12 and 24 months postoperatively, or until the patient died or was lost to follow-up.

RESULTS

Fifteen consecutive patients were successfully treated with CT-guided PVP via a translateral approach. Their mean VAS score decreased from 7.7 ± 2.9 preoperatively to 1.4 ± 1.5 by the 24 hour postoperative time point, and was 1.2 ± 1.3 at 2 weeks, 1.2 ± 1.3 at one month, 1.4 ± 1.3 at 3 months, 0.6 ± 0.9 at 6 months, 0.3 ± 0.5 at 12 months, and 0 at 24 months after the procedure. The mean VAS score at all of the postoperative time points differed significantly from the preoperative baseline score (P < 0.05). No severe complications were observed. Mild complications included 2 cases (13.3%) of asymptomatic cement leakage into the epidural space, one case (6.67%) of anterior leakage from the vertebral body, and 2 cases (13.3%) of paravertebral leakage.

LIMITATIONS

This was an observational study with a relatively small sample size.

CONCLUSIONS

The safety and efficacy of CT-guided PVP using a translateral approach via the space between the carotid sheath and vertebral artery were demonstrated in patients with hemangioma or metastasis in the upper cervical spine. CT-guided PVP via a translateral approach should become a treatment option for such patients.

Effects of heterochromatin in colorectal cancer stem cells on radiosensitivity

BACKGROUND AND OBJECTIVE

Radiotherapy (RT) is a major non-surgical modality in the comprehensive treatment for colorectal adenocarcinoma. The radioresistance of cancer stem cells (CSCs) is a key factor that influences therapeutic effectiveness. This study was to investigate the effects of specific chromosome structure and histone modification in CSCs in colorectal adenocarcinoma radioresistance.

METHODS

Samples were collected from resected human colorectal adenocarcinomas. Subcutaneous colorectal cancer model was established in nude mice. Immunohistochemistry showed that xenografts generated from bulk colorectal cancer cells resembled the original tumor specimen. Flow cytometry was performed to sort CSCs (CD133+) and non-CSCs (CD133-) from both resected samples of colorectal adenocarcinoma and xenograft before and after high single-dose radiation. The markers labeling heterochromatin (H3K9me3, HP1-alpha and H3K4me1) and euchromatin (H3K4me3) in CD133+ and CD133- nucleus were detected by immunofluorescence.

RESULTS

There was distinct difference in chromatin structure between colorectal CSCs (CD133+) and non-CSCs (CD133-). The chromatin displayed compact patches in CD133+ nucleus, but loosely latticed structure in CD133- nucleus; immunofluorescence verified that the compact patches existing in CSCs was generated from heterochromatin construction. In addition, the vacuole-like defect in heterochromatin regions of CSCs was observed within 24 h after exposure to 10 gray (Gy) single-dose RT. Interestingly, this phenomenon was repaired from 96 h, and recovered to dense plaque structure in heterochromatin regions of CSCs after 144 h. However, no significant difference in non-CSCs was observed after RT exception for a loose chromatin structure.

CONCLUSIONS

CSCs play a role in radiosensitivity in colorectal cancer. The mechanism may be related to heterochromatin formation and histone methylation.

[Antitumor effect by combination of shRNA interfering plasmid targeting PKM2 with recombinant endostatin]

OBJECTIVE

To investigate the enhancement effect of the combination of shRNA interfering plasmid targeting PKM2 with recombinant Endostatin in the treatment of lung cancer.

METHODS

Twenty five BABL/nu/nu mice bearing A549 lung cancer were divided into 5 groups (NS control, psh-Control, psh-PKM2 treated group, Endostar treated group, psh-PKM2+Endostar treated group) and treated with shRNA interfering plasmid targeting PKM2 and recombinant Endostatin respectively or in combination. The expression of PKM2 in A549 detected with immunofluorescent assay. The interference effect of psh-PKM2 was determined by Western blot. The tumor volume, microvessel density (MVD), apoptosis index (AI) and side effects were observed.

RESULTS

The combination treatment of RNA interfering plasmid targeting PKM2 with recombinant Endostatin inhibited tumor growth obviously (P < 0.05); The combination group revealed a decreased MVD and an increased AI (P < 0.05).

CONCLUSION

The combination of shRNA interfering plasmid targeting PKM2 with recombinant Endostatin might enhance anti-tumor effect by increasing the apoptosis of the cancer cell.

In-band OSNR monitoring using a pair of Michelson fiber interferometers

Two polarization-independent Michelson fiber interferometers with different optical delays were used to measure the in-band OSNR of an optical signal from 5 to 30 dB within an accuracy of 0.5 dB. Using an expansion of the amplitude autocorrelation function of the signal around zero delay, it was possible to perform measurements without any prior knowledge of the signal. The system is shown to be immune to the effects of modulation frequency (up to 10G), partially and fully polarized noise, chromatic dispersion and poorly biased modulators.

Could changes in arterioles impede the perivascular drainage of interstitial fluid from the cerebral white matter in leukoaraiosis?

AIMS

Leukoaraiosis (LA) is the increase in fluid in cerebral white matter with hyperintensity on T2-weighted MR imaging that occurs in 25% of individuals over 65 years of age and in Alzheimer's disease. Age, hypertension, diabetes mellitus and cardiac disease are the major risk factors for LA. Ischaemia is considered to be the cause of LA, but the aim of the present study is to assess whether changes in arterioles in LA could impede perivascular lymphatic drainage of interstitial fluid from the cerebral white matter.

METHODS

We quantified arteriolosclerosis and immunohistochemical changes in the extracellular matrix in arterioles of cerebral white matter in 20 hypertension autopsy cases with LA and in 10 controls.

RESULTS

The ratio of the area immunoreactive for collagen types I, III, V and VI to the cross-sectional area of arterioles was significantly higher in LA patients compared with controls (P < 0.001). Changes were observed in collagen IV and laminin. The walls of white matter arterioles in LA were significantly thicker (P < 0.01), and lumina were significantly smaller (P < 0.01). Arterioles had a significantly higher sclerotic index [1 - (internal/external diameter)] in LA than in adjacent cortex or control white matter (P < 0.01).

CONCLUSIONS

Our results show that thickening and sclerosis of the walls of arterioles in cerebral white matter in LA are associated with the accumulation of extracellular matrix components. Although these changes may result in decreased perfusion, they could also impede perivascular lymphatic drainage of interstitial fluid from white matter in LA.

Polarization dependence of a GaAs-based two-photon absorption microcavity photodetector

In this paper, the polarization response of a GaAs based two-photon absorption microcavity photodetector has been studied. The deviation in the dependence of the detector response from that of bulk GaAs is shown to be due to the birefringence of the cavity. A theoretical model based on the convolution of the cavity birefringence and the polarization dependence of two-photon absorption in GaAs is described and shown to match the measured polarization dependence of the microcavity detector very well.

Improved therapeutic effectiveness by combining liposomal honokiol with cisplatin in lung cancer model

Background

Honokiol is a major bioactive compound extracted from Magnolia. The present study was designed to determine whether liposomal honokiol has the antitumor activity against human lung cancer as well as potentiates the antitumor activity of cisplatin in A549 lung cancer xenograft model, if so, to examine the possible mechanism in the phenomenon.

Methods

human A549 lung cancer-bearing nude mice were treated with liposomal honokiol, liposomal honokiol plus DDP or with control groups. Apoptotic cells and vessels were evaluated by fluorescent in situ TUNEL assay and by immunohistochemistry with an antibody reactive to CD31 respectively.

Results

The present study showed that liposomal honokiol alone resulted in effective suppression of the tumor growth, and that the combined treatment with honokiol plus DDP had the enhanced inhibition of the tumor growth and resulted in a significant increase in life span. The more apparent apoptotic cells in the tumors treated with honokiol plus DDP was found in fluorescent in situ TUNEL assay, compared with the treatment with control groups. In addition, the combination of honokiol and DDP apparently reduced the number of vessels by immunolabeling of CD31 in the tissue sections, compared with control groups.

Conclusion

In summary, our data suggest that honokiol alone had the antitumor activity against human lung cancer in A549 lung cancer xenograft model, and that the combination of honokiol with DDP can enhance the antitumor activity, and that the enhanced antitumor efficacy in vivo may in part result from the increased induction of the apoptosis and the enhanced inhibition of angiogenesis in the combined treatment. The present findings may be of importance to the further exploration of the potential application of the honokiol alone or the combined approach in the treatment of lung carcinoma.

Annealing study of palladium-silver dental alloys: Vickers hardness measurements and SEM microstructural observations

Three Pd-Ag dental alloys for metal-ceramic restorations, W-1 (Ivoclar Vivadent), Rx 91 (Pentron) and Super Star (Heraeus Kulzer), were subjected to isothermal annealing for 0.5 hr periods in a nitrogen atmosphere at temperatures from approximately 400 degrees to 950 degrees C. The annealing behavior was investigated by Vickers hardness measurements (1 kg load) and SEM microstructural observations. The highest Vickers hardness occurred at approximately 700 degrees C for W-1 and 650 degrees C for Rx 91. For Super Star, there were two peaks in hardness at approximately 500 degrees and 650 degrees C. Additional use of light indenting loads (25 g for W-1; 10 g for Rx 91 and Super Star) revealed that hardness variations during annealing for W-1 and Rx 91 were related to the palladium solid solution matrix phase. For Super Star, the lower-temperature peak was controlled by multi-phase regions and the higher-temperature peak by the matrix phase. While microstructural changes due to annealing were evident with the SEM for Rx 91 and Super Star, no correlation was possible for W-1 because of its finer-scale microstructure. Although commercial Pd-Ag alloys have a relatively narrow composition range, their microstructures and annealing behavior can vary because of differences in proportions of secondary elements utilized for porcelain adherence and grain refinement elements, as well as other proprietary strategies employed by the manufacturers.

Transmission electron microscopic studies of deformed high-palladium dental alloys

Objective. The purpose of this study was to employ transmission electron microscopy (TEM) to investigate the microstructures of Pd-Cu-Ga and Pd-Ga dental alloys that had been permanently deformed, in order to obtain information about the deformation behavior of individual phases and changes in microstructure brought about by that deformation.Methods. Heavily deformed regions taken from fractured tensile test bars of the two alloys in the as-cast condition were prepared for TEM analysis, using mechanical grinding and polishing, ion milling, and plasma cleaning. The specimens were examined in the TEM using bright-field and dark-field diffraction contrast imaging. Selected-area and convergent-beam electron diffraction patterns were employed to analyze the structures of the phases, and standardless energy-dispersive X-ray spectrometry was used to determine their mean compositions.Results. For both alloys, tweed structures underwent permanent deformation by twinning, whereas dislocation movement occurred in the face-centered cubic (fcc) palladium solid solution matrix. A body-centered cubic (bcc) phase, previously unreported in our TEM studies and containing a high density of dislocations, was identified in the Pd-Cu-Ga alloy, while fine-scale, stress-induced precipitates were found in some regions of the fcc matrix in the Pd-Ga alloy.Significance. The present results have provided novel information about the mechanical deformation behavior of high-palladium alloys. The stress-induced precipitation in the Pd-Ga dental alloy studied may be a critical component of strengthening mechanisms.

Transmission electron microscopic investigation of a Pd-Ag-In-Sn dental alloy

With the price volatility of palladium, there has been renewed interest in palladium-silver alloys for metal-ceramic restorations in dentistry. The microstructures of a popular Pd-Ag dental alloy were investigated in the as-cast and simulated porcelain-firing heat-treated conditions, using transmission electron microscopy. In the as-cast condition, the microstructure was strongly influenced by microsegregation, and contained the face-centered cubic Pd solid solution matrix, a eutectic structure with lattice parameters that varied for the two phases, and a face-centered tetragonal (fct) precipitate. After heat treatment, the lattice parameters for the two phases in the eutectic structure were uniform, and discontinuous precipitates with [011](matrix) habit planes and dislocations appeared in the matrix. An unusual nanostructured constituent was found in the fct set of eutectic lamellae in the heat-treated alloys.

Fatigue studies of high-palladium dental casting alloys: Part II. Transmission electron microscopic observations

The microstructures of two representative high-palladium dental alloys, a Pd-Cu-Ga alloy and a Pd-Ga alloy, which had been subjected to cyclic fatigue in uniaxial tension were investigated by transmission electron microscopy (TEM). Two different mechanisms were found to dominate microplastic deformation during fatigue: twinning in the Pd-Cu-Ga alloy, and planar slip of dislocations in the Pd-Ga alloy. In addition, stress-induced precipitation occurred in the Pd-Ga alloy during cyclic loading. Heat treatment simulating the firing cycles for dental porcelain resulted in the formation of a previously unreported bcc phase in the Pd-Cu-Ga alloy, and in the elimination of the characteristic tweed structure found in the Pd-Ga alloy for the as-cast condition.