Chronic replication stress invokes mitochondria dysfunction via impaired parkin activity.

Replication stress is a major contributor to tumorigenesis because it provides a source of chromosomal rearrangements via recombination events. PARK2, which encodes parkin, a regulator of mitochondrial homeostasis, is located on one of the common fragile sites that are prone to rearrangement by replication stress, indicating that replication stress may potentially impact mitochondrial homeostasis. Here, we show that chronic low-dose replication stress causes a fixed reduction in parkin expression, which is associated with mitochondrial dysfunction, indicated by an increase in mtROS. Consistent with the major role of parkin in mitophagy, reduction in parkin protein expression was associated with a slight decrease in mitophagy and changes in mitochondrial morphology. In contrast, cells expressing ectopic PARK2 gene does not show mtROS increases and changes in mitochondrial morphology even after exposure to chronic replication stress, suggesting that intrinsic fragility at PARK2 loci associated with parkin reduction is responsible for mitochondrial dysfunction caused by chronic replication stress. As endogenous replication stress and mitochondrial dysfunction are both involved in multiple pathophysiology, our data support the therapeutic development of recovery of parkin expression in human healthcare.

Nicaraven induces programmed cell death by distinct mechanisms according to the expression levels of Bcl-2 and poly (ADP-ribose) glycohydrolase in cancer cells.

The PARP-1 expression level and poly (ADP-ribosyl)ation activity in cancer markedly affect the therapeutic outcome. Nicaraven, a free radical scavenger has been found to inhibit PARP, but the effect on cancer cells is still unclear. In this study, we investigated the potential role and molecular mechanism of nicaraven on cancer cells. Using U937 lymphoma cells and HCT-8 colorectal cancer cells, we found that nicaraven moderately reduced the cell viability of both cells in a dose-dependent manner. Interestingly, nicaraven significantly induced apoptosis of U937 cells that are dominantly expressing Bcl-2 but induced PAR-dependent cell death (parthanatos) of HCT-8 cells that are highly expressing poly (ADP-ribose) glycohydrolase (PARG). Based on our data, nicaraven seems to induce programmed cell death through distinct mechanisms, according to the expression levels of Bcl-2 and PARG in cancer cells.

A disease-driver population within interstitial cells of human calcific aortic valves identified via single-cell and proteomic profiling.

Cellular heterogeneity of aortic valves complicates the mechanistic evaluation of the calcification processes in calcific aortic valve disease (CAVD), and animal disease models are lacking. In this study, we identify a disease-driver population (DDP) within valvular interstitial cells (VICs). Through stepwise single-cell analysis, phenotype-guided omic profiling, and network-based analysis, we characterize the DDP fingerprint as CD44highCD29+CD59+CD73+CD45low and discover potential key regulators of human CAVD. These DDP-VICs demonstrate multi-lineage differentiation and osteogenic properties. Temporal proteomic profiling of DDP-VICs identifies potential targets for therapy, including MAOA and CTHRC1. In vitro loss-of-function experiments confirm our targets. Such a stepwise strategy may be advantageous for therapeutic target discovery in other disease contexts.

Nicaraven mitigates radiation-induced lung injury by downregulating the NF-κB and TGF-ß/Smad pathways to suppress the inflammatory response.

Radiation-induced lung injury (RILI) is commonly observed in patients receiving radiotherapy, and clinical prevention and treatment remain difficult. We investigated the effect and mechanism of nicaraven for mitigating RILI. C57BL/6 N mice (12-week-old) were treated daily with 6 Gy X-ray thoracic radiation for 5 days in sequences (cumulative dose of 30 Gy), and nicaraven (50 mg/kg) or placebo was injected intraperitoneally in 10 min after each radiation exposure. Mice were sacrificed and lung tissues were collected for experimental assessments at the next day (acute phase) or 100 days (chronic phase) after the last radiation exposure. Of the acute phase, immunohistochemical analysis of lung tissues showed that radiation significantly induced DNA damage of the lung cells, increased the number of Sca-1+ stem cells, and induced the recruitment of CD11c+, F4/80+ and CD206+ inflammatory cells. However, all these changes in the irradiated lungs were effectively mitigated by nicaraven administration. Western blot analysis showed that nicaraven administration effectively attenuated the radiation-induced upregulation of NF-κB, TGF-ß, and pSmad2 in lungs. Of the chronic phase, nicaraven administration effectively attenuated the radiation-induced enhancement of α-SMA expression and collagen deposition in lungs. In conclusion we find that nicaraven can effectively mitigate RILI by downregulating NF-κB and TGF-ß/pSmad2 pathways to suppress the inflammatory response in the irradiated lungs.

[A Case of Scirrhous Gastric Cancer Not Diagnosed by Endoscopy but by Staging Laparoscopy].

A 71-year-old female was referred to our hospital for abdominal distention and anorexia. Gastrointestinal endoscopy revealed wall thickening of the entire circumference. Abdominal CT scan showed diffuse thickening of the stomach, but there was no obvious metastasis. Scirrhous gastric cancer was strongly suspected, but endoscopic biopsies could not demonstrate malignant features. Staging laparoscopy was performed. There was a small amount of ascites and numerous peritoneal dissemination. She was diagnosed with gastric cancer pStage Ⅳ(pT4a, NX, H0, M1, P1, CY1)without HER2 positivity. We experienced a case of scirrhous gastric cancer in which staging laparoscopy was useful for histological diagnosis and staging.

Nicaraven prevents the fast growth of inflamed tumors by an anti-inflammatory mechanism.

Inflammatory microenvironment is known to accelerate the progression of malignant tumors. We investigated the possible anti-inflammatory effect of nicaraven on slowing tumor growth. Tumor-bearing mice randomly received nicaraven injection (50 mg/kg daily, i.p, n = 8) or placebo treatment (n = 8) for 10 days, and then sacrificed for evaluations. Nicaraven administration effectively inhibited the fast growth of tumor, as a large tumor (> 1.0 g) developed finally in three of the eight mice received placebo treatment. Cytokines/chemokines array indicated that nicaraven reduced the levels of CXCL10 and SDF-1 in the tumor as well as the levels of IL-2 and MIP-2 in serum. Immunofluorescence staining showed that nicaraven significantly reduced the recruitment of macrophages and neutrophils in the tumor. Interestingly, western blot indicated that the expression of CD86, CD206, and NIMP-R14 was especially enhanced in the three large-size tumors, suggesting the potential role of nicaraven in preventing the hyper-inflammatory tumor microenvironment. Moreover, the expression of PARP-1 was downregulated, but the expression of phospho-p38 MAPK, phospho-MKK-3/6, and phospho-MSK-1 was upregulated in the large-size tumors, suggesting the involvement of p38 MAPK pathway in the anti-inflammatory effect of nicaraven. Taken together, our study suggests that nicaraven may effectively prevent the fast growth of inflamed tumors by an anti-inflammatory mechanism.

Dipyridamole induces the phosphorylation of CREB to promote cancer cell proliferation.

Dipyridamole, a traditional anti-platelet drug, has been reported to inhibit the proliferation of cancer cells. The present study aimed to investigate the possibility of dipyridamole as an adjuvant of chemotherapy by enhancing the cytotoxicity of an anti-cancer drug. The cytotoxicity of colorectal cancer cells (HCT-8), CD133+/CD44+ stem-like subpopulation of HCT-8 cells and lymphoma cells (U937) to dipyridamole and/or doxorubicin was evaluated using MTT proliferation and colony forming assays. The expression levels of phosphorylated cAMP-regulatory element-binding protein (pCREB) and poly(ADP-ribose) polymerase-1 (PARP-1) in cells were analyzed via western blotting and immunofluorescence. The present study reported controversial data regarding the anti-cancer effect of dipyridamole. Dipyridamole increased, rather than inhibited, the proliferation of HCT-8 and U937 cells in a dose-dependent manner. Furthermore, it was found that dipyridamole significantly increased the expression levels of pCREB and PARP-1. However, the combined usage of dipyridamole significantly enhanced the cytotoxicity of doxorubicin to HCT-8 cells at particular doses. Based on the current findings, dipyridamole likely induces the phosphorylation of CREB to promote the proliferation of cancer cells, but may enhance the cytotoxicity of anti-cancer drugs at particular doses.

Enhanced Expression of ABCB1 and Nrf2 in CD133-Positive Cancer Stem Cells Associates with Doxorubicin Resistance.

The precise mechanism about drug resistance of cancer stem cells (CSCs) has not yet been completely understood. Based on the expression of CD44 and CD133, two well-recognized cell surface markers for CSC identification, we tried to separate HCT8 colorectal cancer cells into different subpopulations and then investigated how the expression of CD44 and CD133 associated with doxorubicin (DXR) resistance. Interestingly, DXR resistance was observed in CD44+CD133+ (P < 0.01vs. all other subpopulations), but not in CD44+CD133- cells. CD44+CD133+ cells also showed an enhanced expression of ABCB1 and drug efflux ability (P < 0.001vs. all other subpopulations), but verapamil, an inhibitor of ABCB1, only partially mitigated the DXR resistance. Independent on the accumulation of DXR, lower level of reactive oxygen species and higher expression of Nrf2 were detected in CD44+CD133+ than CD44+CD133- cells (P < 0.05). Unexpectedly, silencing CD133 by siRNA only partially enhanced the cytotoxicity of DXR, but did not obviously change the expression of ABCB1 and the accumulation of DXR in CD44+CD133+ cells. Complex mechanisms, including drug excretion and redox regulation, are likely involved in the DXR resistance of CD133-positive cells, suggesting the difficulty of drug resistance problem in cancer chemotherapy.

Nicaraven Attenuates Postoperative Systemic Inflammatory Responses-Induced Tumor Metastasis.

BACKGROUND: Inflammation has been demonstrated to promote cancer metastasis. Due to the well-known systemic inflammatory responses (SIR) after major surgery, it is critical to investigate and attenuate SIR-induced tumor metastasis of cancer patients suffering surgical procedures. METHODS: C57BL/6 mice were intravenously injected with Lewis lung cancer cells at 6, 24, and 72 h after the induction of intestinal ischemia/reperfusion (I/R) injury. We found that the number of tumor nodules significantly increased in lungs of mice injected with cancer cells at 6 h but not at 24 and 72 h after I/R injury. The administration of nicaraven 30 min before and 24 h after I/R injury effectively attenuated the enhanced tumor metastasis to lungs. Protein array showed the increase of various cytokines in plasma of mice at 6 h after I/R injury, but many of them were attenuated by the administration of nicaraven. Immunostaining indicated the increase of Ly6g-, CD206-, and CD11c-positive inflammatory cells in the lungs, but it was also attenuated by nicaraven administration. CONCLUSIONS: Postoperative SIR-induced tumor metastasis have been clearly evidenced in our experimental model, and the administration of nicaraven may ameliorate the SIR-induced tumor metastasis by suppressing inflammatory responses.

Retinoids Repress Human Cardiovascular Cell Calcification With Evidence for Distinct Selective Retinoid Modulator Effects.

OBJECTIVE: Retinoic acid (RA) is a ligand for nuclear receptors that modulate gene transcription and cell differentiation. Whether RA controls ectopic calcification in humans is unknown. We tested the hypothesis that RA regulates osteogenic differentiation of human arterial smooth muscle cells and aortic valvular interstitial cells that participate in atherosclerosis and heart valve disease, respectively. Approach and Results: Human cardiovascular tissue contains immunoreactive RAR (RA receptor)-a retinoid-activated nuclear receptor directing multiple transcriptional programs. RA stimulation suppressed primary human cardiovascular cell calcification while treatment with the RAR inhibitor AGN 193109 or RARα siRNA increased calcification. RA attenuated calcification in a coordinated manner, increasing levels of the calcification inhibitor MGP (matrix Gla protein) while decreasing calcification-promoting TNAP (tissue nonspecific alkaline phosphatase) activity. Given that nuclear receptor action varies as a function of distinct ligand structures, we compared calcification responses to cyclic retinoids and the acyclic retinoid peretinoin. Peretinoin suppressed human cardiovascular cell calcification without inducing either secretion of APOC3 (apolipoprotein-CIII), which promotes atherogenesis, or reducing CYP7A1 (cytochrome P450 family 7 subfamily A member 1) expression, which occurred with cyclic retinoids all-trans RA, 9-cis RA, and 13-cis RA. Additionally, peretinoin did not suppress human femur osteoblast mineralization, whereas all-trans RA inhibited osteoblast mineralization. CONCLUSIONS: These results establish retinoid regulation of human cardiovascular calcification, provide new insight into mechanisms involved in these responses, and suggest selective retinoid modulators, like acyclic retinoids may allow for treating cardiovascular calcification without the adverse effects associated with cyclic retinoids.

Standardization of Human Calcific Aortic Valve Disease in vitro Modeling Reveals Passage-Dependent Calcification.

Aortic valvular interstitial cells (VICs) isolated from patients undergoing valve replacement are commonly used as in vitro models of calcific aortic valve disease (CAVD). Standardization of VIC calcification, however, has not been implemented, which impairs comparison of results from different studies. We hypothesized that different culture methods impact the calcification phenotype of human VICs. We sought to identify the key parameters impacting calcification in primary human VICs to standardize CAVD in vitro research. Here we report that in calcification media containing organic phosphate, termed osteogenic media (OM), primary human VICs exhibited a passage-dependent decrease in calcification potential, which was not observed in calcification media containing inorganic phosphate, termed pro-calcifying media (PM). We used Alizarin red staining to compare the calcification potential of VICs cultured in OM and PM between the first and fourth passages after cell isolation from human CAVD tissues. Human VICs showed consistent Alizarin red stain when cultured with PM in a passage-independent manner. VICs cultured in OM did not exhibit consistent calcification potential between donors in early passages and consistently lacked positive Alizarin red stain in late passages. We performed whole cell, cytoplasmic and nuclear fractionation proteomics to identify factors regulating VIC passage-dependent calcification in OM. Proteomics cluster analysis identified tissue non-specific alkaline phosphatase (TNAP) as a regulator of passage-dependent calcification in OM. We verified an association of TNAP activity with calcification potential in VICs cultured in OM, but not in PM in which VICs calcified independent of TNAP activity. This study demonstrates that media culture conditions and cell passage impact the calcification potential of primary human VICs and should be taken into consideration in cell culture models of CAVD. Our results help standardize CAVD modeling as part of a greater effort to identify disease driving mechanisms and therapeutics for this unmet medical need.

Immunomodulatory effect of mesenchymal stem cells: Cell origin and cell quality variations.

The immunomodulatory property of mesenchymal stem cells (MSCs) has been previously reported. Still it is unclear if this property can be affected by the cell origin and cell quality. Using primary MSCs expanded from bone marrow (BM-MSCs) and adipose tissue (AD-MSCs) of mice, we investigated whether the immunomodulatory property of MSCs varied with cell origin and cell quality (early- vs. late-passaged BM-MSCs). BM-MSCs (p1) and AD-MSCs (p1) had a typical spindle shape, but morphological changes were observed in late-passaged BM-MSCs (p6). A pathway-focused array showed that the expression of chemokine/cytokine genes varied with different cell origins and qualities. By co-culturing with spleen mononuclear cells (MNC) for 3 days, the expression of CD4 was suppressed by all types of MSCs. By contrast, the expression of CD8 was suppressed by BM-MSCs and increased by AD-MSCs. The expression ratio of CD206 to CD86 was at a comparable level after co-culture with AD-MSCs and BM-MSCs, but was lower with late-passaged BM-MSCs. AD-MSCs highly induced the release of IL6, IL-10 and TGF-ß in culture medium. Compared with early-passaged BM-MSCs (p1), late-passaged BM-MSCs (p6) released less TGF-ß. Our data suggests that the immunomodulatory properties of MSCs vary with cell origin and cell quality and that BM-MSCs of good quality are likely the optimal source of immunomodulation.

Spatiotemporal Multi-Omics Mapping Generates a Molecular Atlas of the Aortic Valve and Reveals Networks Driving Disease.

BACKGROUND: No pharmacological therapy exists for calcific aortic valve disease (CAVD), which confers a dismal prognosis without invasive valve replacement. The search for therapeutics and early diagnostics is challenging because CAVD presents in multiple pathological stages. Moreover, it occurs in the context of a complex, multi-layered tissue architecture; a rich and abundant extracellular matrix phenotype; and a unique, highly plastic, and multipotent resident cell population. METHODS: A total of 25 human stenotic aortic valves obtained from valve replacement surgeries were analyzed by multiple modalities, including transcriptomics and global unlabeled and label-based tandem-mass-tagged proteomics. Segmentation of valves into disease stage-specific samples was guided by near-infrared molecular imaging, and anatomic layer-specificity was facilitated by laser capture microdissection. Side-specific cell cultures were subjected to multiple calcifying stimuli, and their calcification potential and basal/stimulated proteomes were evaluated. Molecular (protein-protein) interaction networks were built, and their central proteins and disease associations were identified. RESULTS: Global transcriptional and protein expression signatures differed between the nondiseased, fibrotic, and calcific stages of CAVD. Anatomic aortic valve microlayers exhibited unique proteome profiles that were maintained throughout disease progression and identified glial fibrillary acidic protein as a specific marker of valvular interstitial cells from the spongiosa layer. CAVD disease progression was marked by an emergence of smooth muscle cell activation, inflammation, and calcification-related pathways. Proteins overrepresented in the disease-prone fibrosa are functionally annotated to fibrosis and calcification pathways, and we found that in vitro, fibrosa-derived valvular interstitial cells demonstrated greater calcification potential than those from the ventricularis. These studies confirmed that the microlayer-specific proteome was preserved in cultured valvular interstitial cells, and that valvular interstitial cells exposed to alkaline phosphatase-dependent and alkaline phosphatase-independent calcifying stimuli had distinct proteome profiles, both of which overlapped with that of the whole tissue. Analysis of protein-protein interaction networks found a significant closeness to multiple inflammatory and fibrotic diseases. CONCLUSIONS: A spatially and temporally resolved multi-omics, and network and systems biology strategy identifies the first molecular regulatory networks in CAVD, a cardiac condition without a pharmacological cure, and describes a novel means of systematic disease ontology that is broadly applicable to comprehensive omics studies of cardiovascular diseases.

The effect of transient oxygenation on stem cell mobilization and ischemia/reperfusion heart injury.

For general anesthesia, pre-oxygenation is routinely performed prior to intubation. It is well-known that ischemic/hypoxic preconditioning induces stem cell mobilization and protects against ischemia/reperfusion (I/R) injury. In this study, we investigated the effect of transient oxygenation on stem cell mobilization and I/R injury of the heart. Mice were exposed to 100% oxygen for 5 or 20 minutes. We evaluated the number of c-kit+ stem/progenitor cells and the levels of SDF-1α and VEGF in peripheral blood at 1, 3, 6, and 24 hours after oxygenation. We also induced I/R injury of the heart at 3 hours post-oxygenation for 5 minutes and then examined stem cell recruitment and fibrotic changes in the heart 3 or 14 days later. The number of c-kit+ cells in peripheral blood was significantly increased at 1 or 24 hours after oxygenation for either 5 or 20 minutes. Oxygenation for 5 or 20 minutes did not significantly change the SDF-1α level measured in plasma. However, the plasma VEGF level was decreased at 3 hours post-oxygenation for 20 minutes (p = 0.051). Oxygenation for 5 minutes did not significantly alter the fibrotic area or cell apoptosis. Although oxygenation for 5 minutes increased the number of c-kit+ cells in hearts damaged by I/R injury, this difference was not significant between groups due to large variation between individuals (p = 0.14). Although transient oxygenation induces stem cell mobilization, it does not appear to protect against I/R injury of the heart in mice.

Nicaraven reduces cancer metastasis to irradiated lungs by decreasing CCL8 and macrophage recruitment.

Radiotherapy for cancer patients damages normal tissues, thereby inducing an inflammatory response and promoting cancer metastasis. We investigated whether nicaraven, a compound with radioprotective and anti-inflammatory properties, could attenuate radiation-induced cancer metastasis to the lungs of mice. Nicaraven and amifostine, another commercial radioprotective agent, had limited effects on both the radiosensitivity of Lewis lung carcinoma cells in vitro and radiation-induced tumor growth inhibition in vivo. Using experimental and spontaneous metastasis models, we confirmed that thorax irradiation with 5 Gy X-rays dramatically increased the number of tumors in the lungs. Interestingly, the number of tumors in the lungs was significantly reduced by administering nicaraven but not by administering amifostine daily after radiation exposure. Furthermore, nicaraven administration effectively inhibited CCL8 expression and macrophage recruitment in the lungs 1 day after thorax irradiation. Our data suggest that nicaraven attenuates radiation-induced lung metastasis, likely by regulating the inflammatory response after radiation exposure.

Surgical strategy for aortic arch reconstruction after the Norwood procedure based on numerical flow analysis.

OBJECTIVES: Inefficient aortic flow after the Norwood procedure is known to lead to the deterioration of ventricular function due to an increased cardiac workload. To prevent the progression of aortic arch obstruction, arch reconstruction concomitant with second-stage surgery is recommended. The aim of this study was to determine the indications for reconstruction based on numerical simulation and to reveal the morphology that affects the haemodynamic parameters. METHODS: Fifteen patients who underwent the Norwood procedure or arch repair and Damus-Kaye-Stansel anastomosis were enrolled. The pressure gradient in aortic arch was 1.6 ± 3.9 mmHg (ranged from 0 to 12 mmHg) on catheter examination. Six patients who had prominent turbulent flow accompanied with a large flow energy loss index greater than 40 mW/m2 and high wall shear stress greater than 100 Pa underwent arch reconstruction. RESULTS: After arch reconstruction, the energy loss index significantly decreased from 88.5 ± 50.0 mW/m2 to 23.1 ± 10.4 mW/m2 (P = 0.026) and wall shear stress significantly decreased from 194.5 ± 87.4 Pa to 60.3 ± 40.5 Pa (P = 0.0062). There were 3 late deaths due to heart failure caused by progressive atrioventricular valve regurgitation during the follow-up period (60 months). The systemic ventricular function was preserved in the remaining patients without any pressure gradients in the arch. CONCLUSIONS: Determining the surgical strategy for arch reconstruction based on numerical flow analysis may effectively reduce the ventricular load even if no stenosis or pressure gradients are observed on catheter examination or echocardiography.

Risk factors for difficulty of laparoscopic cholecystectomy in grade II acute cholecystitis according to the Tokyo guidelines 2013.

BACKGROUND: The Tokyo Guidelines 2013 classifies acute cholecystitis (AC) into three grades and recommends appropriate therapy for each grade. For grade II AC, either early laparoscopic cholecystectomy (LC) or percutaneous transhepatic gallbladder drainage (PTGBD) should be performed. This study aimed to identify the risk factors for difficulty of LC for treating grade II AC. METHODS: Totally, 122 patients who underwent LC for grade II AC were enrolled and divided into difficult LC (DLC) and nondifficult LC (NDLC) groups. The DLC group included patients who experienced one of the following conditions: conversion from LC to open cholecystectomy, operating time ≥ 180 min, or blood loss ≥300 ml. Preoperative characteristics and postoperative outcomes were analyzed. RESULTS: In univariate analysis, risk factors included male sex, interval between symptom onset and admission, interval between symptom onset and LC, and anticoagulant therapy. The incidence of postoperative complications was higher in the DLC group than in the NDLC group (23.5% vs. 4.6%, p = 0.0016). According to receiver operating characteristic curves, the optimal cutoff value was calculated, and multivariate analysis showed that male sex [odds ratio (OR), 5.76; 95% confidence interval (CI), 1.979-19.51; p = 0.0009) and interval between symptom onset and LC of over 96 h (OR, 6.32; 95% CI, 2.126-20.15; p = 0.0009) were independent risk factors for difficulty of LC. CONCLUSIONS: In patients with grade II AC, LC was technically difficult when performed over 96 h after symptom onset. Moreover, male sex was a risk factor. Therefore, PTGBD should be considered in these patients.

Extreme dilatation of the interposed jejunal pouch after proximal gastrectomy associated with portal venous gas: A case report.

INTRODUCTION: The jejunal pouch interposition (JPI) after proximal gastrectomy (PG) was proposed as a reconstructive procedure to provide a gastric reservoir substitute and prevent postgastrectomy syndrome. However, food residue remaining in some of the pouches resulted in the adverse effect of abdominal bloating, thereby body weight loss. Here, we report a rare case with an extreme dilation of the interposed jejunal pouch (JP) 8 years after PG, requiring pouch resection. PRESENTATION OF CASE: A 65-year-old-man who had undergone PG with an inverted U-shaped JPI for early gastric cancer 8 years previously, suffered from shock after right hip joint implantation. Abdominal enhanced CT scan revealed an extremely dilated JP accompanied by portal venous gas. After 5 months of conservative therapy, he underwent resection of the JP and gastric remnant with Roux-en-Y esophagojejunostomy reconstruction. After the operation, the patient has remained in good health for over 3 years. DISCUSSION AND CONCLUSION: Long-term operative outcome following pouch operation for gastric cancer still remains controversial. Surgical intervention should be considered when we encounter patients who have refractory pouch dilatation after surgery for gastric cancer.

Optimal timing of cholecystectomy after percutaneous gallbladder drainage for severe cholecystitis.

BACKGROUND: The Tokyo guideline for acute cholecystitis recommended percutaneous transhepatic gallbladder drainage followed by cholecystectomy for severe acute cholecystitis, but the optimal timing for the subsequent cholecystectomy remains controversial. METHODS: Sixty-seven patients who underwent either laparoscopic or open cholecystectomy after percutaneous transhepatic gallbladder drainage for severe acute cholecystitis were enrolled and divided into difficult cholecystectomy (group A) and non-difficult cholecystectomy (group B). Patients who had one of these conditions were placed in group A: 1) conversion from laparoscopic to open cholecystectomy; 2) subtotal cholecystectomy and/or mucoclasis; 3) necrotizing cholecystitis or pericholecystic abscess formation; 4) tight adhesions around the gallbladder neck; and 5) unsuccessfully treated using PTGBD. Preoperative characteristics and postoperative outcomes were analyzed. RESULTS: The interval between percutaneous transhepatic gallbladder drainage and cholecystectomy in Group B was longer than that in Group A (631 h vs. 325 h; p = 0.031). Postoperative complications occurred more frequently when the interval was less than 216 h compared to when it was more than 216 h (35.7 vs. 7.6%; p = 0.006). CONCLUSIONS: Cholecystectomy for severe acute cholecystitis was technically difficult when performed within 216 h after percutaneous transhepatic gallbladder drainage.

Dynamin-Related Protein 1 Inhibition Attenuates Cardiovascular Calcification in the Presence of Oxidative Stress.

RATIONALE: Mitochondrial changes occur during cell differentiation and cardiovascular disease. DRP1 (dynamin-related protein 1) is a key regulator of mitochondrial fission. We hypothesized that DRP1 plays a role in cardiovascular calcification, a process involving cell differentiation and a major clinical problem with high unmet needs. OBJECTIVE: To examine the effects of osteogenic promoting conditions on DRP1 and whether DRP1 inhibition alters the development of cardiovascular calcification. METHODS AND RESULTS: DRP1 was enriched in calcified regions of human carotid arteries, examined by immunohistochemistry. Osteogenic differentiation of primary human vascular smooth muscle cells increased DRP1 expression. DRP1 inhibition in human smooth muscle cells undergoing osteogenic differentiation attenuated matrix mineralization, cytoskeletal rearrangement, mitochondrial dysfunction, and reduced type 1 collagen secretion and alkaline phosphatase activity. DRP1 protein was observed in calcified human aortic valves, and DRP1 RNA interference reduced primary human valve interstitial cell calcification. Mice heterozygous for Drp1 deletion did not exhibit altered vascular pathology in a proprotein convertase subtilisin/kexin type 9 gain-of-function atherosclerosis model. However, when mineralization was induced via oxidative stress, DRP1 inhibition attenuated mouse and human smooth muscle cell calcification. Femur bone density was unchanged in mice heterozygous for Drp1 deletion, and DRP1 inhibition attenuated oxidative stress-mediated dysfunction in human bone osteoblasts. CONCLUSIONS: We demonstrate a new function of DRP1 in regulating collagen secretion and cardiovascular calcification, a novel area of exploration for the potential development of new therapies to modify cellular fibrocalcific response in cardiovascular diseases. Our data also support a role of mitochondrial dynamics in regulating oxidative stress-mediated arterial calcium accrual and bone loss.