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Fractional flow reserve (FFR) is considered to be the criterion standard for the clinical diagnosis of functional myocardial ischemia. In this study, we explored the effect of the coronary arterial diameter derived from coronary computed tomography angiography on FFR.We retrospectively reviewed the clinical information of 131 patients with moderate coronary artery stenosis. To compare the mean diameter of stenotic vessels, patients were divided into ischemic and nonischemic groups. According to the clinical statistics of the diameter of the ischemic group and the nonischemic group, we established 8 ideal models of coronary artery diameter of 4 mm (40%, 50%, 60%, and 70% stenosis) and diameter of 3 mm (40%, 50%, 60%, and 70% stenosis). Two sets of numerical simulation experiments were carried out: experiment 1 evaluated the variation rate of CT-based computation of non-invasive fractional flow reserve (FFRCT) with vessel diameters of 4 mm and 3 mm under different stenosis rates, and experiment 2 explored the variation of FFRCT with vessel diameters of 4 mm and 3 mm under different cardiac outputs. We simulated changes in the flow of narrow blood vessels by changes in cardiac output.According to clinical statistics, the mean ± SD diameter of stenotic vessels in the ischemic and nonischemic groups was 3.67 ± 0.77 mm and 3.31 ± 0.64 mm (P0.05 for difference), respectively. In experiment 1, the FFRCT of coronary with a diameter of 4 mm was 0.86, 0.80, 0.66, and 0.35, and that with a diameter of 3 mm was 0.90, 0.84, 0.71, and 0.50, respectively. In experiment 2, the FFRCT of the coronary vessel diameter of 4 mm was 0.84, 0.80, 0.76, and 0.72, respectively. The FFRCT coronary vessels with a diameter of 3 mm were 0.87, 0.84, 0.80, and 0.76, respectively.As the stenosis increases, compared with narrow blood vessel of small diameter, the narrow blood vessel with larger diameter is accompanied by faster flow rate changes and is more prone to ischemia.

Transthoracic ultrasound is widely used in to diagnose and treat lung diseases, such as pneumonia, atelectasis, pneumothorax and pulmonary edema. Recently, intraoperative transthoracic ultrasound was used to promptly identify two cases of early pneumothorax in patients that underwent liver surgery. We documented the process of pneumothorax occurrence and the patient outcomes. Timely discovery and effective real-time monitoring and evaluation of the scope of pneumothorax ensured the smooth completion of the operation and successfully avoided closed thoracic drainage in one case, avoiding further patient trauma. Indeed, intraoperative ultrasound is an effective approach to diagnose and evaluate pneumothorax that does not affect the progress of surgery and is more convenient and sensitive than conventional chest radiography.

The objective of this study is to explore the effect of acute appendicitis and chronic cholecystitis on inflammatory factors and intestinal mucosal function during operation.This was a prospective cohort study. Forty-four patients including those who underwent elective cholecystectomy (Group A, n = 22) or emergency appendectomy (Group B, n = 22) were recruited. Before anesthesia and after surgery, arterial blood was collected for the measurement of plasma indices associated with inflammation or intestinal permeability. Both the tumor necrosis factor-alpha (TNF-α) and C-reactive protein (CRP) levels were higher in Group B than in Group A (P 0.05). The preoperative IL-10 level was higher in Group A than in Group B (P = 0.036), while after surgery, the opposite relationship was observed (P = 0.020). There were no intergroup or intragroup differences for D-Lac. The postoperative lipopolysaccharide (LPS) and human syndecan-1 (Sdc-1) levels were lower than the corresponding preoperative value (P 0.05) in the two groups. Both the preoperative Sdc-1 and fatty acid binding protein (FABP2) levels in Group A were higher than the corresponding levels in Group B (P 0.05).The study suggested that chronic cholecystitis had more severe damage to intestinal mucosal function than acute appendicitis. It is necessary to strengthen the protection of intestinal mucosa during the perioperative period.

A quick calculation approach of steady-state fractional flow reserve (FFRss) based on computed tomography angiography (CTA) images is a reliable non-invasive way of calculate FFR, the assumptions used in the research should be study further to increase forecast accuracy. The effect of inlet and outlet boundary conditions on FFRss was investigated.15 patients who had been diagnosed with coronary artery disease were enrolled in this study. We investigated the sensitivity of calculating FFR to boundary circumstances, using invasive FFR as a benchmark. There are two types of inlet: (1) aortic pressure based on clinically measured. (2) mean pressure calculated based on physiological formula; we further studied the outlet changes of FFRss under different coronary vasodilation responses (24%, 48%, 72%).According to the calculate FFR results of all patients, FFRA numerical analysis of the effects of proximal and distal boundary constraints of computational models on computed CT-FFR is presented. The findings revealed that distal boundary circumstances (hyperemic vasodilation response of coronary micro-vessels) have a significant impact on FFR, providing evidence to guide the development and application of a computational model for estimating FFR.

Dexmedetomidine (DEX), a highly selective α2 receptor agonist. DEX can inhibit the release of inflammatory factors in septic rats. It can also protect against H2O2 injury by up-regulating HIF-1α expression. The aim of this study was to explore whether DEX can up regulate HIF-1ɑ protein level and plays a role in reducing septic intestinal mucosal injury. Twenty-four Sprague Dawley (SD) rats were randomly divided into four groups of 6 rats each: the sham group, sepsis group (subjected to cecal ligation and perforation, CLP), sepsis + dexmedetomidine group (DEX group, 30 µg/kg of DEX by intraperitoneal injection 30 minutes before and 2 hours after CLP), and sepsis + DEX + HIF-1ɑ inhibitor Bay87-2243 (Bay87-2243 group, 30 µg/kg of DEX by intraperitoneal injection 30 minutes before and 2 hours after CLP and 9mg/kg of bay87-2243 by oral administration for 3 days before CLP. The HIF-1ɑ and the tight junction protein (TJs) was detected by Western blot; the plasma concentrations of diamine oxidase (DAO), intestinal fatty acid binding protein (FABP2) and D-lactic acid (D-LAC) were detected by ELISA; the morphological changes of intestinal mucosa were detected by HE staining. DEX significantly increased the expression level of HIF-1ɑ on intestinal mucosa in rats with sepsis injury, thus ameliorated intestinal mucosal pathological injury, reduced Chiu’s score, decreased intestinal mucosal permeability, and up-regulated TJs protein expression. Moreover, effect on sepsis induced intestinal mucosal injury of DEX was reversed by HIF-1ɑ inhibitor Bay87-2243. DEX could protect against sepsis-induced intestinal mucosal injury by up-regulating HIF-1ɑ expression in rats.

Objective Venous-arterial venous extracorporeal membrane oxygenation (V-AV ECMO), as a new clinical application of ECMO, showed great clinical application potential in the treatment of patients with combined cardiopulmonary failure. Given the complicated cannulation strategy of V-AV ECMO, its influence on the hemodynamics of the human circulatory system remained unclear. Methods In this paper, a fluid–structure interaction was used to study the effect of V-AV ECMO oxygenated blood shunt ratio on right atrial recirculation and tricuspid valve (TV) blood oxygen saturation. In this study, the right atrium, superior vena cava supplying cannulae and inferior vena cava draining cannulae model of a specific patient was constructed. Seven cases with shunt ratio of 12.50%, 18.75%, 25.00%, 31.25%, 37.50%, 43.75% and 50.00% were designed. Results The streamline diagram and velocity contour of oxygenated blood, recirculation fraction (RF), correlation of three variables (shunt ratio, RF, and oxygen saturation), and the oxygen saturation of blood at the TV were extracted for the study. Study results showed that, first, as the shunt ratio increased, the RF of the seven cases was 14.64%, 29.87%, 33.85%, 40.12%, 40.40%, 40.02%, and 38.09%. Second, with the increase of the shunt ratio, oxygen saturation of blood at the TV in seven cases was 82.1%, 82.5%, 83.3%, 83.3%, 84.0%, 84.6%, and 85.3%. Conclusions In this study, the shunt ratio had a strong correlation with the RF and oxygen saturation of blood at the TV. As the shunt ratio increased, the RF initially increased and then stabilized. However, oxygen saturation of blood at the TV would increase with the increase of the shunt ratio, but the degree of increase was small. This research provided useful information for surgeons and operators using V-AV ECMO.

Coil embolization has become a new treatment method for pulsatile tinnitus (PT) caused by sigmoid sinus diverticulum (SSD). Although this therapy has achieved good results in clinical reports, the hemodynamic mechanism of coils in the treatment of PT in SSD remained unclear.Finite element method (FEM) and computational fluid dynamics (CFD) were combined to explore the hemodynamic mechanism of coil embolization in SSD treatment. Three personalized geometric models of sigmoid sinus were established according to the CTA data of patients. Coil model were established by FEM, and the hemodynamic differences of SSD before and after coiling were compared by transient CFD method.Velocity streamlines disappeared in the SSD after coiling. At the peak time (t1 = 0.22 s), the SSD-average velocity decreased in every patient. The average value of the decreased in three patients was 0.154 ± 0.028 m/s (mean ± SD). Wall average pressure (PA reduction in SSD-average velocity, wall pressure, and WSS were the short-term hemodynamic mechanism of coil embolization for PT. Coil embolization increased the proportion of low-velocity region in the SSCPD area, thereby creating a hemodynamic environment that easily produced thrombus and protects blood vessels from the impact of blood flow. This phenomenon was the long-term effect of coil embolization.

In this study, we explored the effect of vessel diameter of coronary artery where the stenosis is located on FFR at the same vascular level. This study is divided into two parts: clinical statistics and numerical simulation. In the clinical statistics section, we compared the blood vessel diameter where the stenosis is located of the ischemic group and the non-ischemic group. In the numerical simulation section, we further explored the effect of diameter on myocardial ischemia by using an ideal model. With the increase in stenosis rate and stenotic vessel flow, the FFR rate of the larger stenotic vessels was higher than that of smaller stenotic vessels. The larger blood vessels are more prone to ischemia when coronary artery stenosis occurs.

Sigmoid sinus wall dehiscence (SSWD) is a common pathophysiology of patients with pulsatile tinnitus (PT). However, the pathological mechanism of SSWD is unclear. This study aimed to investigate the relationship between the position of the SSWD and blood flow pattern of the transverse sinus and sigmoid sinus (TS-SS) junction. The impact of the blood flow was hypothesized to be the pathological mechanism of SSWD. Twenty patients and two healthy volunteers were analyzed retrospectively, and transient computer fluid dynamics was used to verify this hypothesis. A 4D flow magnetic resonance imaging experiment was performed to validate the numerical simulation. The position of high-velocity blood flow impacting the vessel wall (17/20) was consistent with SSWD. In healthy volunteers, the temporal bone was thin where the blood flow impacted the blood vessel wall. The average wall shear stress (20/20) and pressure (18/20) of the SSWD area (peak) were higher than those of sigmoid sinus wall anomalies (the contact area between the vessel wall and the temporal bone at the TS-SS junction). The average wall pressure percentage differences of 16/20, 11/20, and 4/20 patients were more than 5%, 10%, and 20%, respectively. The average wall shear stress percentage differences of 20/20, 18/20, and 16/20 patients were more than 5%, 10%, and 20%, respectively. In brief, the blood flow of the TS-SS junction impacted the vessel wall and increased wall pressure, which might be an important pathological mechanism of SSWD. This study could serve as a basis for the diagnosis and SSWD resurfacing surgery of patients with PT induced by SSWD.

Sigmoid sinus diverticulum (SSD) is a common pathophysiology of pulsatile tinnitus (PT) and mainly treated by SSD reconstruction surgery. The degree of reconstruction is an important indicator of SSD reconstruction surgery, but its impact on the effect of SSD reconstruction is unclear. This study aimed to clarify the effect of the degree of SSD reconstruction on diverticulum reconstruction surgical treatment. One patient-specific case (control subject) was reconstructed based on the computed tomography angiography (CTA) images of patients with PT. The SSD reconstruction degree was used as a new index in this study. And the case of 30% (case 1), 60% (case 2), and 100% (case 3) of the diverticulum reconstruction degree of control subject were constructed. Transient-state computational fluid dynamics was performed. Wall pressure distribution, wall average pressure (Pavg) of SSD, flow pattern (velocity streamlines and velocity vector), wall shear stress (WSS) and averaged WSS (WSSavg) were calculated and used in evaluating the hemodynamic differences among the DRD cases. Results demonstrated that change in SSD pressure was not linear with increase in DRD. The DRD that reached 60% of the original diverticulum was effective. At the peak point of the inlet boundary condition (T1 = 0.22s), the Pavg of SSD had a nonlinear change (control subject, 126.967 Pa vs. case 1, 126.274 Pa vs. case 2, 106.897 Pa vs. case 3, 94.116 Pa). Flow vorticity decreased gradually, and the smoothness of the streamlines increased with DRD. WSSavg slightly changed with increasing DRD. The high-speed flow blood hit the diverticulum entrance and then swirled to hit the area of the sigmoid sinus wall abnormal. It was concluded that flow patterns related to PT differ with DRD. In diverticulum reconstruction surgery, there is a threshold value, and only when the DRD exceeds this value (60% or 70% or 80%), it will have a noticeable effect. In this study, DRD should at least reach 60% of the original diverticulum. When DRD is insufficient, hemodynamic change in the diverticulum is small, and the PT may have remained. SSD may be caused by high-speed blood flow.

A ratiometric fluorescent sensor for the detection of Fe

Limited population-based cancer registry data available in China until now has hampered efforts to inform cancer control policy. Following extensive efforts to improve the systematic cancer surveillance in this country, we report on the largest pooled analysis of cancer survival data in China to date. Of 21 population-based cancer registries, data from 17 registries (n = 138,852 cancer records) were included in the final analysis. Cases were diagnosed in 2003-2005 and followed until the end of 2010. Age-standardized relative survival was calculated using region-specific life tables for all cancers combined and 26 individual cancers. Estimates were further stratified by sex and geographical area. The age-standardized 5-year relative survival for all cancers was 30.9% (95% confidence intervals: 30.6%-31.2%). Female breast cancer had high survival (73.0%) followed by cancers of the colorectum (47.2%), stomach (27.4%), esophagus (20.9%), with lung and liver cancer having poor survival (16.1% and 10.1%), respectively. Survival for women was generally higher than for men. Survival for rural patients was about half that of their urban counterparts for all cancers combined (21.8% vs. 39.5%); the pattern was similar for individual major cancers except esophageal cancer. The poor population survival rates in China emphasize the urgent need for government policy changes and investment to improve health services. While the causes for the striking urban-rural disparities observed are not fully understood, increasing access of health service in rural areas and providing basic health-care to the disadvantaged populations will be essential for reducing this disparity in the future.

Limited population-based cancer registry data available in China until now has hampered efforts to inform cancer control policy. Following extensive efforts to improve the systematic cancer surveillance in this country, we report on the largest pooled analysis of cancer survival data in China to date. Of 21 population-based cancer registries, data from 17 registries (n = 138,852 cancer records) were included in the final analysis. Cases were diagnosed in 2003-2005 and followed until the end of 2010. Age-standardized relative survival was calculated using region-specific life tables for all cancers combined and 26 individual cancers. Estimates were further stratified by sex and geographical area. The age-standardized 5-year relative survival for all cancers was 30.9% (95% confidence intervals: 30.6%-31.2%). Female breast cancer had high survival (73.0%) followed by cancers of the colorectum (47.2%), stomach (27.4%), esophagus (20.9%), with lung and liver cancer having poor survival (16.1% and 10.1%), respectively. Survival for women was generally higher than for men. Survival for rural patients was about half that of their urban counterparts for all cancers combined (21.8% vs. 39.5%); the pattern was similar for individual major cancers except esophageal cancer. The poor population survival rates in China emphasize the urgent need for government policy changes and investment to improve health services. While the causes for the striking urban-rural disparities observed are not fully understood, increasing access of health service in rural areas and providing basic health-care to the disadvantaged populations will be essential for reducing this disparity in the future.

From Dec. 1976 through June 1986, 474 patients with acute leukemia were treated with central nervous system (CNS) irradiation for the purpose of preventing relapse of CNS leukemia. Of the whole series, whole cranial irradiation at a dosage of 24 Gy and 4–5 intrathecal instillations of methotrexate (MTX) were given in 149 patients, simple intrathecal instillation of MTX in 44 patients and high dose intravenous MTX in 5 patients; the CNS relapse rates were 4.0%, 20.5% and 40.0% respectively. It was proved by our experience that whole cranial irradiation plus intrathecal MTX is the best approach to prevention of CNS leukemia relapses.