Plasmonic optical fiber for bacteria manipulation—characterization and visualization of accumulation behavior under plasmo-thermal trapping

In this article, we demonstrate a plasmo-thermal bacterial accumulation effect using a miniature plasmonic optical fiber. The combined action of far-field convection and a near-field trapping force (referred to as thermophoresis)—induced by highly localized plasmonic heating—enabled the large-area accumulation of Escherichia coli. The estimated thermophoretic trapping force agreed with previous reports, and we applied speckle imaging analysis to map the in-plane bacterial velocities over large areas. This is the first time that spatial mapping of bacterial velocities has been achieved in this setting. Thus, this analysis technique provides opportunities to better understand this phenomenon and to drive it towards in vivo applications.     

GABA(B) receptor-mediated presynaptic inhibition of glycinergic transmission onto substantia gelatinosa neurons in the rat spinal cord

The GABA_B receptor-mediated presynaptic inhibition of glycinergic transmission was studied from young rat substantia gelatinosa (SG) neurons using a conventional whole-cell patch clamp technique. Action potential-dependent glycinergic inhibitory postsynaptic currents (IPSCs) were recorded from SG neurons in the presence of 3 mM kynurenic acid and 10 μM SR95531. In these conditions, baclofen (30 μM), a selective GABA_B receptor agonist, greatly reduced the amplitude of glycinergic IPSCs and increased the paired-pulse ratio. Such effects were completely blocked by 3 μM CGP55845, a selective GABA_B receptor antagonist, indicating that the activation of presynaptic GABA_B receptors decreases glycinergic synaptic transmission. Glycinergic IPSCs were largely dependent on Ca²⁺ influxes passing through presynaptic N- and P/Q-type Ca²⁺ channels, and these channels contributed equally to the baclofen-induced inhibition of glycinergic IPSCs. However, the baclofen-induced inhibition of glycinergic IPSCs was not affected by either 100 μM SQ22536, an adenylyl cyclase inhibitor, or 1 mM Ba²⁺, a G-protein coupled inwardly rectifying K⁺ channel blocker. During the train stimulation (10 pulses at 20 Hz), which caused a marked synaptic depression of glycinergic IPSCs, baclofen at a 30 μM concentration completely blocked glycinergic synaptic depression, but at a 3 μM concentration it largely preserved glycinergic synaptic depression. Such GABA_B receptor-mediated dynamic changes in short-term synaptic plasticity of glycinergic transmission onto SG neurons might contribute to the central processing of sensory signals.     

KIOM-79 inhibits high glucose or AGEs-induced VEGF expression in human retinal pigment epithelial cells

We evaluated whether KIOM-79, a mixture of extracts obtained from Puerariae lobata, Magnolia officinalis, Glycyrrhiza uralensis and Euphorbia pekinensis, could inhibit vascular endothelial growth factor (VEGF) expression in human retinal pigment epithelial (RPE) cells cultured under high glucose (HG, 25mM) or S100b (a specific ligand of the receptor for advance glycation end products (RAGE), 5microg/ml). In this study, the effect of KIOM-79 on HG or S100b-induced VEGF expression was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, RT-PCR, ELISA, and Western blot on human RPE cells. The MTT assay (p<0.01) revealed that KIOM-79 (up to 1mg/ml) had no effect on cell growth. HG or S100b induced an increase in expression of VEGF at both mRNA and protein levels (p<0.05; p<0.01 versus control). The increase in VEGF expression by HG or S100b was dose- and time-dependently prevented by KIOM-79 (p<0.05 versus 25mM glucose; p<0.01 versus S100b). Also, KIOM-79 inhibited protein kinase C (PKC)-alpha/beta(alpha) and p38 mitogen-activated protein kinase (MAPK) activation. Our results demonstrate that KIOM-79 can inhibit VEGF expression via inhibition of the MAPK and PKC pathway.     

Assessment of Hepatic Arterial Anatomy in Keeping with Preservation of the Vasculature While Performing Pancreatoduodenectomy: An Opinion

Background Pancreatic surgeons often must make decisions regarding hepatic artery (HA) resection while performing a pancreatoduodenectomy (PD). The purpose of this report was to review and summarize HA resection experience with a focus on vascular preservation during PD and to develop a useful guideline for pancreatic surgeons in dealing with these needs. Methods We reviewed 1324 cases that had available computed tomographic and angiographic findings and summarized the problematic HA variations encountered in PD. In reviewing our PD series (n = 254), we have created a set of guidelines that enable a pragmatic approach to the unique variations in HA and the risks of cancer invasion. Results Challenging HA variations during PD were found in 20.1% of the cases and included the common HA arising from the superior mesenteric artery (SMA) (2.34%), a replaced right HA (RHA) from the SMA (9.82%), an RHA or left HA from the gastroduodenal artery (0.97%), and the right anterior or right posterior HA from the SMA (1.06%), among others. In our PD series, the problematic HAs (15.8%) were preserved, except for a single case (0.4%) in which PD involved en bloc resection of the RHA from the SMA due to a cancerous invasion and without right hemihepatectomy. Conclusions Surgeons should have knowledge of the anatomically variable vasculature of the HA when planning for PD. Preoperative imaging studies can aid and should be performed in anticipation of the potential HA variations during PD.     

Contemporary results of open repair of ruptured descending thoracic and thoracoabdominal aortic aneurysms

OBJECTIVE: The purpose of this study was to evaluate the results of open repair for ruptured descending thoracic and thoracoabdominal aortic aneurysm (RDTAA). METHODS: A retrospective review identified 41 consecutive cases of open surgical repair in 40 patients presenting with nontraumatic, atherosclerotic RDTAA from 1996 to 2006. Patients with traumatic injuries or complicated dissections were excluded. Patient characteristics and preoperative, intraoperative, and postoperative variables were collected from the medical record. Univariate and logistic regression were used to identify factors contributing to mortality and morbidity in these patients. RESULTS: The operative mortality rate was 26.8% (11/41). All but two deaths occurred within 24 hours of operation; seven were intraoperative. Overall actuarial survival rates at 1 and 2 years were 53.7% and 47.1%, respectively. For those who survived to hospital discharge, the respective numbers were 73.3% and 64.4%. Intraoperative hypotension and blood transfusion requirements were independent predictors of perioperative death. Octogenarians had a mortality rate equivalent to that of the younger population (25% vs 27.6%; not significant). There was a strong trend toward an improved outcome in the latter part (2003-2006) compared with the first part (1995-2002; 13.6% vs 42.1%, respectively; P = .075). CONCLUSIONS: Direct open repair for RDTAA can be achieved with acceptable mortality and morbidity rates even in elderly patients. Improved outcome can be expected with increased volume and experience. This series should help establish a reference against which the results of endovascular endeavors and hybrid procedures could be compared.     

Low risk prostate cancer in men under age 65: the case for definitive treatment

The management of low risk prostate cancer, defined as Gleason’s sum ≤6, PSA <10 ng/ml, and clinical stage T1c to T2a, remains controversial. There is substantiating evidence to suggest that a subset of early stage, low risk cancers can cause significant patient morbidity and death in the long term. Studies have shown that the natural history of untreated prostate cancer is to progress, particularly after 15 years of followup. The majority of men seeking definitive surgical treatment in contemporary series fall within 55 to 65 years of age and are expected to enjoy an overall life expectancy ranging from about 15 to 30 years, placing these men at long-term risk for disease progression and prostate cancer-specific death if managed expectantly. During the past 2 decades, refinements in surgical technique and in the delivery of external beam radiation have resulted in excellent long-term cancer control and favorable quality of life outcomes following treatment. Active surveillance with selective delayed intervention assumes that an individual’s cancer will not progress outside the window of curability during the surveillance period, that markers for disease progression are reliable, and that patients are compliant. Until we understand better the long-term natural history of untreated prostate cancer, have more reliable and accurate markers to detect disease progression with certainty, and can risk stratify more precisely the subgroup of men with low risk cancers who will eventually succumb to their disease, early definitive therapy seems prudent.