How to prevent adverse events of vascular stapling in thoracic surgery: recommendations based on a clinical and experimental study

Background

Advances in the development of staplers for pulmonary vessels have contributed to safe and convenient procedures in thoracic surgery. However, adverse events (AEs) can occur during vascular stapling and cause fatal hemorrhage. We aimed to assess the risk level of using the vessel stapling procedure to reduce such AEs.

Methods

First, an animal experiment using pig cardiopulmonary blocks was conducted. Pulmonary arteries were closed with staplers under stressful conditions such as lifting or twisting; vessel stump endurance was analyzed through different methods. Second, AEs associated with clinical stapler use for pulmonary vessels were retrospectively reviewed by studying clinical videos of 263 patients.

Results

In the animal experiment, the pressure resistance was significantly lower in the twisted group than in the no strain group (no strain vs. lifting: P=0.2008, no strain vs. twisting: P=0.002, no strain vs. twisting and lifting: P<0.0001). Regarding clinical stapler use, 754 staplers were used against the vessels. AEs occurred in 9 cases, and 7 cases were suspected to be caused by vessel tension.

Conclusions

The pulmonary vessel stapling causes stress due to twisting and lifting that decreased stump durability. Avoiding such stress when using stapler for vessels leads to a safer thoracic surgery.

Lipin-1 is a novel substrate of protein phosphatase PGAM5

Lipin-1 has multiple functions that regulate lipid and energy metabolism according to its subcellular localization. The subcellular localization of Lipin-1 is determined by kinase-dependent phosphorylation; however, the phosphatase that dephosphorylates and inactivates Lipin-1 has remained elusive. Using an immunoprecipitation and LC-MS/MS approach we have identified phosphoglycerate mutase family member 5 (PGAM5), a serine/threonine specific protein phosphatase, as a regulator of Lipin-1 activity. Treatment of human hepatocellular carcinoma cells with carbonyl cyanide m-chlorophenyl hydrazone (CCCP), which activates endogenous PGAM5, promoted dephosphorylation and nuclear accumulation of Lipin-1. Our findings further elucidate the molecular mechanisms that regulate Lipin-1.

The Robo4-TRAF7 complex suppresses endothelial hyperpermeability in inflammation

Roundabout guidance receptor 4 (Robo4) is an endothelial cell-specific receptor that stabilizes the vasculature in pathological angiogenesis. Although Robo4 has been shown to suppress vascular hyperpermeability induced by vascular endothelial growth factor (VEGF) in angiogenesis, the role of Robo4 in inflammation is poorly understood. In this study, we investigated the role of Robo4 in vascular hyperpermeability during inflammation. Endotoxemia models using Robo4 ^-/- mice showed increased mortality and vascular leakage. In endothelial cells, Robo4 suppressed tumor necrosis factor α (TNFα)-induced hyperpermeability by stabilizing VE-cadherin at cell junctions, and deletion assays revealed that the C-terminus of Robo4 was involved in this suppression. Through binding and localization assays, we demonstrated that in endothelial cells, Robo4 binds to TNF receptor-associated factor 7 (TRAF7) through interaction with the C-terminus of Robo4. Gain- and loss-of-function studies of TRAF7 with or without Robo4 expression showed that TRAF7 is required for Robo4-mediated suppression of hyperpermeability. Taken together, our results demonstrate that the Robo4-TRAF7 complex is a novel negative regulator of inflammatory hyperpermeability. We propose this complex as a potential future target for protection against inflammatory diseases.

Associations of Skeletal Muscle Mass, Lower-Extremity Functioning, and Cognitive Impairment in Community-Dwelling Older People in Japan

OBJECTIVE

We examined whether skeletal muscle mass and lower extremity functioning are closely associated with multiple cognitive domains, including global cognition, memory, attention, executive functioning, and processing speed, in community-dwelling older Japanese adults.

DESIGN

A cross-sectional, population-based community study.

SETTING

This study was conducted among community-living older people enrolled in the Obu Study of Health Promotion for the Elderly.

PARTICIPANTS

Participants comprised 5,104 adults (≥ 65 years, mean age: 71 years).

MEASUREMENTS

Data from 4273 participants were analyzed. Appendicular skeletal muscle mass was estimated from bioelectrical impedance analysis and expressed as appendicular skeletal muscle mass index (ASMI). Lower-extremity functioning was assessed by the Five-Times-Sit-to-Stand test (FTSS) and Timed Up and Go test (TUG). Cognitive functions were assessed by the Mini Mental State Examination, word list memory, Trail Making Test parts A and B, and Symbol Digit Substitution Task. Logistic regression analysis were performed to calculate odds ratios (ORs) of cognitive impairment in various domains among skeletal muscle mass, lower-extremity functioning levels adjusted for important demographic variables, and comorbidities.

RESULTS

Participants with lower ASMI and slower FTSS and TUG groups had lower cognitive functioning scores than did participants with higher ASMI and faster FTSS and TUG. The slowest quartiles (Q4) of FTSS and TUG were significantly associated with impaired global functioning (MMSE score < 24) compared to the fastest quartile (Q1) after multivariate adjustment (FTSS, OR = 1.46, 95% confidence interval (CI) = 1.12-1.90; TUG, OR = 1.65, 95% CI = 1.25-2.17). In other dimensions of cognitive functioning, FTSS and TUG were significantly associated with all cognitive impairment in the full adjustment model.

CONCLUSION

Lower-extremity functioning, rather than skeletal muscle mass, is closely related to multiple cognitive domains. This study suggests that maintaining lower-extremity functioning, rather than skeletal muscle mass, may be required for detecting and preventing cognitive impairment.

Cell-autonomous and redundant roles of Hey1 and HeyL in muscle stem cells: HeyL requires Hes1 to bind diverse DNA sites

The undifferentiated state of muscle stem (satellite) cells (MuSCs) is maintained by the canonical Notch pathway. Although three bHLH transcriptional factors, Hey1, HeyL, and Hes1, are considered to be potential effectors of the Notch pathway exerting anti-myogenic effects, neither HeyL nor Hes1 inhibits myogenic differentiation of myogenic cell lines. Furthermore, whether these factors work redundantly or cooperatively is unknown. Here, we showed cell-autonomous functions of Hey1 and HeyL in MuSCs using conditional and genetic null mice. Analysis of cultured MuSCs revealed anti-myogenic activity of both HeyL and Hes1. We found that HeyL forms heterodimeric complexes with Hes1 in living cells. Moreover, our ChIP-Seq experiments demonstrated that, compared with HeyL alone, HeyL-Hes1 heterodimer bound with high affinity to specific sites in the chromatin including the cis-element of Hey1. Finally, the analyses of myogenin promoter activity showed that HeyL and Hes1 acted synergistically to suppress myogenic differentiation. Collectively, those results suggest that HeyL and Hey1 function redundantly in MuSCs, and that HeyL requires Hes1 for effective DNA binding and biological activity.

X-ray diffraction study on the orientation dynamics of biaxial microcrystals under static and rotating magnetic fields

The orientation of microcrystals of DyBa₂Cu₃O_y (y ~ 7) under static and rotating magnetic fields was studied.

Development of a detection method for antisense oligonucleotides in mouse kidneys by matrix-assisted laser desorption/ionization imaging mass spectrometry

RATIONALE

Oligonucleotide therapeutics have recently gained much attention, but its pharmacokinetic evaluation methods are still not sufficient, and, in particular, more tools are needed to evaluate their tissue distribution and metabolites. We developed a matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS)-based method to evaluate the tissue distribution of oligonucleotide therapeutics.

METHODS

We used an antisense oligonucleotide containing locked nucleic acids (LNA-A). Various washing protocols were examined using mouse kidney homogenate sections. Next, we applied a two-step matrix preparation strategy. As a first step, 3-hydroxypicolinic acid (3-HPA) matrix containing citrate and amines was sprayed using an airbrush and subsequently 3-HPA matrix containing citrate only was sprayed using the ImagePrep. Finally, kidney sections prepared from LNA-A-dosed mice were treated with our optimized method and analyzed with MALDI-IMS.

RESULTS

The selected washing method made it possible to detect LNA-A with MALDI-IMS and, furthermore, our developed matrix pretreatment method enhanced signal intensity approximately two-fold. MALDI-IMS revealed that LNA-A localized in a portion presumed to be the renal cortex. We also obtained information on LNA-A metabolites, which showed the same distribution profile as LNA-A in kidneys.

CONCLUSIONS

This study shows that MALDI-IMS can be applied to evaluate the tissue distribution of oligonucleotide therapeutics. Our method can evaluate the tissue distribution along with metabolites and has the potential to help the development of novel oligonucleotide therapeutics.

[Successful Treatment of a Patient with Idiopathic Subglottic Stenosis]

Idiopathic subglottic stenosis (ISS) is defined as the narrowing of the upper airway without any known cause. A 40-year-old female was referred to our hospital with the complaint of exacerbation of dyspnea causing difficulty in going out. Chest computed tomography (CT) scan and bronchoscopy revealed subglottic tracheal stenosis with a luminal diameter of 5 mm at the narrowest part. Tracheal mucosa of the stenotic lesion was smooth, and the patient had no previous medical history. Subglottic tracheal resection of the stenotic lesion and reconstruction were performed. The postoperative course was good, and the symptom of dyspnea improved significantly. Recently, some reports have suggested conservative treatments such as laser and balloon dilation for ISS, but the recurrence rate after these treatments is still high. Surgery is recommended rather than conservative treatments for patients with less severe inflammation of tracheal mucosa and other comorbidities like present case.

ROS1-rearranged high-PD-L1-expressing lung adenocarcinoma manifesting as mediastinal tumor: A case report

ROS proto-oncogene 1 receptor tyrosine kinase (ROS1)-rearranged lung cancer is rare and comprises only 1% of lung adenocarcinoma cases. It has recently been reported to have good response to crizotinib, a tyrosine kinase inhibitor of anaplastic lymphoma kinase. Driver oncogene mutations with approved therapies seldom coexist with a high expression of Programmed death-ligand 1 (PD-L1). The present case report describes a rare case of ROS1 rearrangement with high-PD-L1-expressing occult lung adenocarcinoma. A 32-year-old woman presented with chest pain and a prolonged cough. Chest computed tomography (CT) revealed a 57×36-mm tumor in the mediastinum, with no tumors detected in other regions. Positron emission tomography (PET)-CT showed a strong fluorodeoxyglucose accumulation in the tumor (SUVmax 13.2). Mediastinal tumor resection was completely resected using a video-assisted thoracic surgery approach. Pathological examination showed the tumor cells were positive for thyroid transcription factor 1, Napsin-A, ROS1, and PD-L1 (tumor proportion score >99%). ROS1 rearrangement was confirmed by fluorescence in situ hybridization. The mediastinal tumor was diagnosed as mediastinal lymph node metastasis of ROS1-rearranged PD-L1 high-expression undifferentiated lung adenocarcinoma (pathological stage 3, TxN2M0). Two months after the operation, the CT scan showed multiple mediastinum lymph nodes metastases with rapid tumor growth. The patient achieved a complete response after three cycles of S-1 plus cisplatin with concurrent radiotherapy 60 Gy/30 Fr.

[Solitary Pulmonary Metastasis from Carcinoma of the Ampulla of Vater after Pancreatoduodenectomy;Report of a Case]

A 74-year-old woman had underwent pancreatoduodenectomy for a carcinoma of the ampulla of Vater. After 3 years of the operation, chest computed tomography (CT) scan showed a solitary nodule in the right posterior segment (S2). Under the diagnosis of solitary pulmonary metastasis, we performed wedge resection for the right S2 lesion under video-assisted thoracic surgery (VATS). Pathological diagnosis was the metastasis of carcinoma of the ampulla of Vater. One year later, chest CT scan showed another solitary lesion in right superior segment (S6). Wedge resection was performed again for the right S6 nodule, which was also diagnosed as a metastasis.

[Continuous Chest Drainage Systems in Thoracic Surgery]

In the management of chest drain after thoracic surgery, it is important to egest fluid and air which accumulate in the pleural cavity and to gain information such as air leakage, bleeding or pus discharge. To achieve these purpose, continuous chest drainage system is necessary for thoracic surgery. In addition, we have to understand the particularity in the pleural cavity and the structure of continuous chest drainage system. Traditional drainage system is based on 3-bottle system. Recently, we can use new drainage system, such as Thopaz, which is called digital drainage system. There are several studies comparing digital drainage system with traditional drainage system, but the superiority of digital drainage system to traditional drainage system is not confirmed.

[Pulmonary Metastasis of Gastric Cancer as Carcinomatous Lymphangiosis at Five and Half Years after Surgery;Report of a Case]

A 51-year-old woman underwent radical operation for a gastric cancer and adjuvant chemotherapy with tegafur, gimeracil, and oteracil potassium. Five and a half years later, screening chest computed tomography(CT)scan showed slight ground glass opacity(GGO)of the both lungs and they were regarded as inflammatory change. Several months later, she experienced a dry cough. CT scan showed aggravation of GGO, and she was refered to our hospital to investigate these lesions 6 years after operation. We performed a wedge resection of right middle lobe. A postoperative pathology revealed metastatic carcinomatous lymphangiosis of gastric cancer. Chemotherapy using capecitabine and oxaliplatin, and then docetaxel was performed and talc pleurodesis was done for the malignant pleural effusion. These treatments did not improve condition, and she died 7 months after lung operation. In conclusion, we need to consider GGO as the possibility of carcinomatous lymphangiosis in case of patient with gastric cancer.