158 research outputs found
Efficacy of carotid thrombus penetration with a balloon guiding catheter to fast recanalization of acute extra- and intra-cranial carotid artery tandem occlusion
Acute ischemic stroke with ipsilateral Internal carotid artery (ICA) stenosis presents a great management dilemma. We present our preliminary report of retrograde retrieval of clot from middle cerebral artery (MCA) followed by delayed carotid artery stenting (CAS) with dual anti platelet therapy (DAPT)
4 electron temperature driven ultrafast electron localization
Valence transitions in strongly correlated electron systems are caused by
orbital hybridization and Coulomb interactions between localized and
delocalized electrons. The transition can be triggered by changes in the
electronic structure and is sensitive to temperature variations, applications
of magnetic fields, and physical or chemical pressure. Launching the transition
by photoelectric fields can directly excite the electronic states and thus
provides an ideal platform to study the correlation among electrons on
ultrafast timescales. The EuNi(SiGe) mixed-valence
metal is an ideal material to investigate the valence transition of the Eu ions
via the amplified orbital hybridization by the photoelectric field on
sub-picosecond timescales. A direct view on the 4 electron occupancy of the
Eu ions is required to understand the microscopic origin of the transition.
Here we probe the 4 electron states of EuNi(SiGe)
at the sub-ps timescale after photoexcitation by X-ray absorption spectroscopy
across the Eu -absorption edge. The observed spectral changes due to the
excitation indicate a population change of total angular momentum multiplet
states = 0, 1, 2, and 3 of Eu, and the Eu = 7/2 multiplet
state caused by an increase in 4 electron temperature that results in a 4
localization process. This electronic temperature increase combined with
fluence-dependent screening accounts for the strongly non-linear effective
valence change. The data allow us to extract a time-dependent determination of
an effective temperature of the 4 shell, which is also of great relevance in
the understanding of metallic systems' properties, such as the ultrafast
demagnetization of ferromagnetic rare-earth intermetallics and their
all-optical magnetization switching.Comment: 19 pages, 9 figure
The Role of Nephritis-Associated Plasmin Receptor (NAPlr) in Glomerulonephritis Associated with Streptococcal Infection
It is well known that glomerulonephritis can occur after streptococcal infection, which is classically referred to as acute poststreptococcal glomerulonephritis (APSGN). The pathogenic mechanism of APSGN has been described by so-called immune complex theory, which involves glomerular deposition of nephritogenic streptococcal antigen and subsequent formation of immune complexes in situ and/or the deposition of circulating antigen-antibody complexes. However, the exact entity of the causative antigen has remained a matter of debate. We isolated a nephritogenic antigen for APSGN from the cytoplasmic fractions of group A streptococcus (GAS) depending on the affinity for IgG of APSGN patients. The amino acid and the nucleotide sequences of the isolated protein revealed to be highly identical to those of reported plasmin(ogen) receptor of GAS. Thus, we termed this antigen nephritis-associated plasmin receptor (NAPlr). Immunofluorescence staining of the renal biopsy tissues with anti-NAPlr antibody revealed glomerular NAPlr deposition in essentially all patients with early-phase APSGN. Furthermore, glomerular plasmin activity was detected by in situ zymography in the distribution almost identical to NAPlr deposition in renal biopsy tissues of APSGN patients. These data suggest that NAPlr has a direct, nonimmunologic function as a plasmin receptor and may contribute to the pathogenesis of APSGN by maintaining plasmin activity
Bile Duct Regeneration with an Artificial Bile Duct Made of Gelatin Hydrogel Nonwoven Fabrics
Although choledochojejunostomy is the standard technique for biliary reconstruction, there are various associated problems that need to be solved such as reflux cholangitis. Interposition with an artificial bile duct (ABD) to replace the resected bile duct maintains a physiological conduit for bile and may solve this problem. This study investigated the usefulness of an ABD made of gelatin hydrogel nonwoven fabric (GHNF). GHNF was prepared by the solution blow spinning method. The migration and activity of murine fibroblast L929 cells were examined in GHNF sheets. L929 cells migrated into GHNF sheets, where they proliferated and synthesized collagen, suggesting GHNF is a promising scaffold for bile duct regeneration. ABDs made of GHNF were implanted in place of resected bile duct segments in rats. The rats were killed at 2, 6, and 12 weeks postimplantation. The implantation site was histologically evaluated for bile duct regeneration. At postoperative 2 weeks, migrating cells were observed in the ABD pores. The implanted ABD was mostly degraded and replaced by collagen fibers at 6 weeks. Ki67-positive bile duct epithelial cells appeared within the implanted ABD. These were most abundant within the central part of the ABD after 6 weeks. The percentages of Ki67-positive cells were 31.7 ± 9.1% in the experimental group and 0.8 ± 0.6% in the sham operation group at 6 weeks (p < 0.05), indicating that mature biliary epithelial cells at the stump proliferated to regenerate the biliary epithelium. Biliary epithelial cells had almost completely covered the bile duct lumen at 12 weeks (epithelialization ratios: 10.4 ± 6.9% at 2 weeks, 93.1 ± 5.1% at 6 weeks, 99.2 ± 1.6% at 12 weeks). The regenerated epithelium was positive for the bile duct epithelium marker cytokeratin 19. Bile duct regeneration was accompanied by angiogenesis, as evidenced by the appearance of CD31-positive vascular structures. Capillaries were induced 2 weeks after implantation. The number of capillaries reached a maximum at 6 weeks and decreased to the same level as that of normal bile ducts at 12 weeks. These results showed that an ABD of GHNF contributed to successful bile duct regeneration in rats by facilitating the cell migration required for extracellular matrix synthesis, angiogenesis, and epithelialization. Impact Statement Development of an artificial bile duct (ABD) enables physiological biliary reconstruction and may solve clinical problems associated with choledochojejunostomy. In this study, we created ABDs with gelatin hydrogel nonwoven fabric and implanted them in place of resected bile duct in rats. We evaluated the process of bile duct regeneration as well as decomposition of the ABD and demonstrated successful regeneration of resected bile duct, highlighting the possibility of this novel biliary reconstruction method to replace choledochojejunostomy
Deletion of both p62 and Nrf2 spontaneously results in the development of nonalcoholic steatohepatitis
Nonalcoholic steatohepatitis (NASH) is one of the leading causes of chronic liver disease worldwide. However, details of pathogenetic mechanisms remain unknown. Deletion of both p62/Sqstm1 and Nrf2 genes spontaneously led to the development of NASH in mice fed a normal chow and was associated with liver tumorigenesis. The pathogenetic mechanism (s) underlying the NASH development was investigated in p62:Nrf2 double-knockout (DKO) mice. DKO mice showed massive hepatomegaly and steatohepatitis with fat accumulation and had hyperphagia-induced obesity coupled with insulin resistance and adipokine imbalance. They also showed dysbiosis associated with an increased proportion of gram-negative bacteria species and an increased lipopolysaccharide (LPS) level in feces. Intestinal permeability was elevated in association with both epithelial damage and decreased expression levels of tight junction protein zona occludens-1, and thereby LPS levels were increased in serum. For Kupffer cells, the foreign body phagocytic capacity was decreased in magnetic resonance imaging, and the proportion of M1 cells was increased in DKO mice. In vitro experiments showed that the inflammatory response was accelerated in the p62:Nrf2 double-deficient Kupffer cells when challenged with a low dose of LPS. Diet restriction improved the hepatic conditions of NASH in association with improved dysbiosis and decreased LPS levels. The results suggest that in DKO mice, activation of innate immunity by excessive LPS flux from the intestines, occurring both within and outside the liver, is central to the development of hepatic damage in the form of NASH
Ability of minimally invasive surgery to decrease incisional surgical site infection occurrence in patients with colorectal cancer and other gastroenterological malignancies
BackgroundSurgical site infection (SSI) is one of the most important complications of surgery for gastroenterological malignancies because it leads to a prolonged postoperative hospital stay and increased inpatient costs. Furthermore, SSI can delay the initiation of postoperative treatments, including adjuvant chemotherapy, negatively affecting patient prognosis. Identifying the risk factors for SSI is important to improving intra- and postoperative wound management for at-risk patients.MethodsPatients with gastroenterological malignancies who underwent surgery at our institution were retrospectively reviewed and categorized according to the presence or absence of incisional SSI. Clinicopathological characteristics such as age, sex, body mass index, malignancy location, postoperative blood examination results, operation time, and blood loss volume were compared between groups. The same analysis was repeated of only patients with colorectal malignancies.ResultsA total of 528 patients (330 men, 198 women; mean age, 68 ± 11 years at surgery) were enrolled. The number of patients with diseases of the esophagus, stomach, small intestine, colon and rectum, liver, gallbladder, and pancreas were 25, 150, seven, 255, 51, five, and 35, respectively. Open surgery was performed in 303 patients vs. laparoscopic surgery in 225 patients. An incisional SSI occurred in 46 patients (8.7%). Multivariate logistic regression analysis showed that postoperative hyperglycemia (serum glucose level ≥140 mg/dl within 24 h after surgery), colorectal malignancy, and open surgery were independent risk factors for incisional SSI. In a subgroup analysis of patients with colorectal malignancy, incisional SSI occurred in 27 (11%) patients. Open surgery was significantly correlated with the occurrence of incisional SSI (P = 0.024).ConclusionsPostoperative hyperglycemia and open surgery were significant risk factors for SSI in patients with gastroenterological malignancies. Minimally invasive surgery could reduce the occurrence of incisional SSI
Snail accelerates cancer invasion by upregulating MMP expression and is associated with poor prognosis of hepatocellular carcinoma
We have previously demonstrated in an in vitro study that Snail increased the invasion activity of hepatoma cells by upregulating matrix metalloproteinase (MMP) gene expression. In the present study, we examined whether Snail gene expression correlates with cancer invasion and prognosis of patients with hepatocellular carcinoma (HCC). Quantitative reverse transcription–polymerase chain reaction (RT–PCR) was performed to evaluate Snail, E-cadherin, and MMP mRNA expressions in eight nodule-in-nodule tumours and 47 ordinary HCC tissues. In the nodule-in-nodule tumours, Snail expression significantly increased with tumour dedifferentiation (P=0.047). In the ordinary HCC tissues, Snail expression was significantly correlated with portal vein invasion (P=0.035) and intrahepatic metastasis (P=0.050); it also showed a significant correlation with MT1-MMP expression (r=0.572, P<0.001). In recurrence-free survival, the group with high Snail expression showed significantly poorer prognosis (P=0.035). Moreover, high Snail expression was an independent risk factor for early recurrence after curative resection. During the progression of HCC, Snail expression may be induced and accelerate invasion activity by upregulating MMP expression, resulting in portal invasion, intrahepatic metastasis, and poor prognosis
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