Refractory and Active Ulcerative Colitis Complicated by Venous Thrombosis: a Case Report

ULCERATIVE colitis is a chronic inflammatorydisease characterized by diffuse mucosalinflammation involving the rectum and extendingproximally to involve all or part of the colon. Astep-up approach for medical therapy is routinely applied,from 5-aminosalicylic acid （ASA） compounds, corticosteroids,immunomodulators, and biologics.1 Thrombosis, mainlyvenous, is a rare and well-recognized extra-intestinalmanifestation of inflammatory bowel disease.2 In thisarticle, we report the use of thrombolytic and antithrombotictherapy for the venous thrombosis in a 55-year-old malepatient with refractory and active ulcerative colitis withexcellent outcome.

Relationship of VEGF/VEGFR with immune and cancer cells:staggering or forward?

Vascular endothelial growth factor(VEGF) is primarily known as a proangiogenic factor and is one of the most important growth and survival factors affecting the vascular endothelium. However, recent studies have shown that VEGF also plays a vital role in the immune environment. In addition to the traditional growth factor role of VEGF and VEGF receptors(VEGFRs), they have a complicated relationship with various immune cells. VEGF also reportedly inhibits the differentiation and function of immune cells during hematopoiesis. Dendritic cells(DCs), macrophages, and lymphocytes further express certain types of VEGF receptors.VEGF can be secreted as well by tumor cells through the autocrine pathway and can stimulate the function of cancer stemness.This review will provide a paradigm shift in our understanding of the role of VEGF/VEGFR signaling in the immune and cancer environment.

Twenty-four-hour ambulatory blood pressure changes in older patients with essential hypertension receiving monotherapy or dual combination antihypertensive drug therapy

Objective To evaluate the differences in 24-hour ambulatory blood pressure (BP) in older patients with hypertension treated with the five major classes of antihypertensive drugs,as monotherapy or dual combination therapy,to improve daytime and nighttime BP control. Methods We enrolled 1920 Chinese community-dwelling outpatients aged ≥ 60 years and compared ambulatory BP values and ambulatory BP control (24-hour BP < 130/80 mmHg;daytime mean BP < 135/85 mmHg;and nighttime mean BP < 120/70 mmHg),as well as nighttime BP dip patterns for monotherapy and dual combination therapy groups. Results Patients’ mean age was 71 years,and 59.5% of patients were women. Calcium channel blockers (CCBs) constituted the most common (60.3% of patients) monotherapy,and renin–angiotensin system (RAS) blockers combined with CCBs was the most common (56.5% of patients) dual combination therapy. Monotherapy with beta-blockers (BB) provided the best daytime BP control. The probabilities of having a nighttime dip pattern and nighttime BP control were higher in patients receiving diuretics compared with CCBs (OR = 0.52,P = 0.05 and OR = 0.41,P = 0.007,respectively). Patients receiving RAS/diuretic combination therapy had a higher probability of having controlled nighttime BP compared with those receiving RAS/CCB (OR = 0.45,P = 0.004). Compared with RAS/diuretic therapy,BB/CCB therapy had a higher probability of achieving daytime BP control (OR = 1.27,P = 0.45). Conclusions Antihypertensive monotherapy and dual combination drug therapy provided different ambulatory BP control and nighttime BP dip patterns. BB-based regimens provided lower daytime BP,whereas diuretic-based therapies provided lower nighttime BP,compared with other antihypertensive regimens.

Estimation of Treatment Effects in Nonlinear Models with Unobserved Confounding

Estimation of treatment effects is one of the crucial mainstays in economics and sociology studies.The problem will become more serious and complicated if the treatment variable is endogenous for the presence of unobserved confounding.The estimation and conclusion are likely to be biased and misleading if the endogeny of treatment variable is ignored.In this article,we propose the pseudo maximum likelihood method to estimate treatment effects in nonlinear models.The proposed method allows the unobserved confounding and random error terms to exist in an arbitrary relationship(such as,add or multiply),and the unobserved confounding have different influence directions on treatment variables and outcome variables.The proposed estimator is consistent and asymptotically normally distributed.Simulation studies show that the proposed estimator performs better than the special regression estimator,and the proposed method is stable for various distribution of error terms.Finally,the proposed method is applied to the real data that studies the influence of individuals have health insurance on an individual’s decision to visit a doctor.

Two-step Estimation for Longitudinal Data When the Working Correlation Matrix is a Linear Combination of Some Known Matrices

The generalized estimating equations(GEE) approach is perhaps one of the most widely used methods for longitudinal data analysis. While the GEE method guarantees the consistency of its estimators under working correlation structure misspecification, the corresponding efficiency can be severely affected. In this paper, we propose a new two-step estimation method in which the correlation matrix is assumed to be a linear combination of some known working matrices. Asymptotic properties of the new estimators are developed.Simulation studies are conducted to examine the performance of the proposed estimators. We illustrate the methodology with an epileptic data set.

A power conversion system for PMSG-based WECS operating with fully-controlled current-source converters

We propose a new power conversion system for a permanent magnet synchronous generator(PMSG) based grid-connected wind energy conversion system(WECS) operating with fully-controlled back-to-back current-source converters. On the generator side, two independent current-source rectifiers(CSRs) with space-vector pulse width modulation(SVPWM) are employed to regulate and stabilize DC-link currents. Between DC-link and the electrical grid, a direct-type three-phase five-level current-source inverter(CSI) is inserted as a buffer to regulate real and reactive power fed to the grid and thus adjusts the grid side power-factor. We also present a current-based maximum power point tracking(MPPT) scheme, which helps the generator extract the maximum power through closed-loop regulation of the generator speed. By applying the multilevel modulation and control strategies to the grid-side five-level CSI, a multilevel output current waveform with less distortion is produced, and the bulk requirement of the output capacitor filter to eliminate the harmonic current is reduced. All the proposed concepts are verified by simulation models built in a PSIM environment.