Iliac vein compression syndrome: Clinical, imaging and pathologic findings

May-Thurner syndrome(MTS) is the pathologic compression of the left common iliac vein by the right common iliac artery, resulting in left lower extremity pain, swelling, and deep venous thrombosis. Though this syndrome was first described in 1851, there are currently no standardized criteria to establish the diagnosis of MTS. Since MTS is treated by a wide array of specialties, including interventional radiology, vascular surgery, cardiology, and vascular medicine, the need for an established diagnostic criterion is imperative in order to reduce misdiagnosis and inappropriate treatment. Although MTS has historically been diagnosed by the presence of pathologic features, the use of dynamic imaging techniques has led to a more radiologic based diagnosis. Thus, imaging plays an integral part in screening patients for MTS, and the utility of a wide array of imaging modalities has been evaluated. Here, we summarize the historical aspects of the clinical features of this syndrome. We then provide a comprehensive assessment of the literature on the efficacy of imaging tools available to diagnose MTS. Lastly, we provide clinical pearls and recommendations to aid physicians in diagnosing the syndrome through the use of provocative measures.

A handy review of carpal tunnel syndrome:From anatomy to diagnosis and treatment

Carpal tunnel syndrome(CTS) is the most commonly diagnosed disabling condition of the upper extremities. It is the most commonly known and prevalent type of peripheral entrapment neuropathy that accounts for about 90% of all entrapment neuropathies. This review aims to provide an outline of CTS by considering anat-omy, pathophysiology, clinical manifestation, diagnostic modalities and management of this common condition, with an emphasis on the diagnostic imaging evaluation.

Immune response after photodynamic therapy increases anti-cancer and anti-bacterial effects

Photodynamic therapy(PDT) is a clinically approved procedure for treatment of cancer and infections. PDT involves systemic or topical administration of a photosensitizer(PS), followed by irradiation of the diseased area with light of a wavelength corresponding to an absorbance band of the PS. In the presence of oxygen, a photochemical reaction is initiated, leading to the generation of reactive oxygen species and cell death. Besides causing direct cytotoxic effects on illuminated tumor cells, PDT is known to cause damage to the tumor vasculature and induce the release of pro-inflammatory molecules. Pre-clinical and clinical studies have demonstrated that PDT is capable of affecting both the innate and adaptive arms of the immune system. Immune stimulatory properties of PDT may increase its beneficial effects giving the therapy wider potential to become more extensively used in clinical practice. Be-sides stimulating tumor-specific cytotoxic T-cells capable to destroy distant untreated tumor cells, PDT leads to development of anti-tumor memory immunity that can potentially prevent the recurrence of cancer. The immunological effects of PDT make the therapy more effective also when used for treatment of bacterial infections, due to an augmented infiltration of neutrophils into the infected regions that seems to potentiate the outcome of the treatment.

Sex, ApoE4 and Alzheimer's disease: rethinking drug discovery in the era of precision medicine

Alzheimer's disease(AD) is the most common cause of dementia and presents with an insidious onset and long prodromal period. Despite billions spent on clinical trials and decades of research, there are currently no disease modifying therapies approved for AD.

Customized Prediction of Short Length of Stay Following Elective Cardiac Surgery in Elderly Patients Using a Genetic Algorithm

Objective: To develop a customized short LOS (gery, using local data and a computational feature selection algorithm. Design: Utilization of a machine learning algorithm in a prospectively collected STS database consisting of patients who received cardiac surgery between January 2002 and June 2011. Setting: Urban tertiary-care center. Participants: Geriatric patients aged 70 years or older at the time of cardiac surgery. Interventions: None. Measurements and Main Results: Predefined morbidity and mortality events were collected from the STS database. 23 clinically relevant predictors were investigated for short LOS prediction with a genetic algorithm (GenAlg) in 1426 patients. Due to the absence of an STS model for their particular surgery type, STS risk scores were unavailable for 771 patients. STS prediction achieved an AUC of 0.629 while the GenAlg achieved AUCs of 0.573 (in those with STS scores) and 0.691 (in those without STS scores). Among the patients with STS scores, the GenAlg features significantly associated with shorter LOS were absence of congestive heart failure (CHF) (OR = 0.59, p = 0.04), aortic valve procedure (OR = 1.54, p = 0.04), and shorter cross clamp time (OR = 0.99, p = 0.004). In those without STS prediction, short LOS was significantly correlated with younger age (OR = 0.93, p 0.001), absence of CHF (OR = 0.53, p = 0.007), no preoperative use of beta blockers (OR = 0.66, p = 0.03), and shorter cross clamp time (OR = 0.99, p 0.001). Conclusion: While the GenAlg-based models did not outperform STS prediction for patients with STS risk scores, our local-data-driven approach reliably predicted short LOS for cardiac surgery types that do not allow STS risk calculation. We advocate that each institution with sufficient observational data should build their own cardiac surgery risk models.

Double Crossover Points in the DFA of Heartbeats in Patients with Sleep Apnea

Cardiovascular and cerebrovascular events have been observed during night-time associated with periodic breathing including sleep apnea and Cheyne-Stokes respiration. Early detection and treatment is important to reduce night-time events. We clarified the characteristics of the dynamic nature of heartbeats associated with periodic breathing by using detrended fluctuation analysis (DFA). We analyzed heartbeats in eight recordings from the MIT-BIH Polysomnographic database. We observed two crossover points and defined three scaling exponents, β1 (n ≤ 40 beats), β2 (50 ≤ n ≤ 200), and β3 (251 ≤ n ≤ 1584). Compared with β1 (1.21 ± 0.13) and β3 (0.92 ± 0.16), scaling exponent β2 (0.62 ± 0.16) showed the statistically lowest value (p 0.05). And there was a negative relationship between the scaling exponent β2 and apnea/hypopnea index (p 0.05). These results indicate that DFA analysis of heartbeats may be useful for the early detection of sleep associated breathing disorders including sleep apnea and its severity.

A toolkit of thread-based microfluidics,sensors,and electronics for 3D tissue embedding for medical diagnostics

Threads,traditionally used in the apparel industry,have recently emerged as a promising material for the creation of tissue constructs and biomedical implants for organ replacement and repair.The wicking property and flexibility of threads also make them promising candidates for the creation of three-dimensional(3D)microfluidic circuits.In this paper,we report on thread-based microfluidic networks that interface intimately with biological tissues in three dimensions.We have also developed a suite of physical and chemical sensors integrated with microfluidic networks to monitor physiochemical tissue properties,all made from thread,for direct integration with tissues toward the realization of a thread-based diagnostic device(TDD)platform.The physical and chemical sensors are fabricated from nanomaterial-infused conductive threads and are connected to electronic circuitry using thread-based flexible interconnects for readout,signal conditioning,and wireless transmission.To demonstrate the suite of integrated sensors,we utilized TDD platforms to measure strain,as well as gastric and subcutaneous pH in vitro and in vivo.

3D cellular-resolution imaging in arteries using few-mode interferometry

Cross-sectional visualisation of the cellular and subcellular structures of human atherosclerosis in vivo is significant,as this disease is fundamentally caused by abnormal processes that occur at this scale in a depth-dependent manner.However,due to the inherent resolution-depth of focus tradeoff of conventional focusing optics,today’s highestresolution intravascular imaging technique,namely,optical coherence tomography(OCT),is unable to provide crosssectional images at this resolution through a coronary catheter.Here,we introduce an intravascular imaging system and catheter based on few-mode interferometry,which overcomes the depth of focus limitation of conventional highnumerical-aperture objectives and enables three-dimensional cellular-resolution intravascular imaging in vivo by a submillimetre diameter,flexible catheter.Images of diseased cadaver human coronary arteries and living rabbit arteries were acquired with this device,showing clearly resolved cellular and subcellular structures within the artery wall,such as individual crystals,smooth muscle cells,and inflammatory cells.The capability of this technology to enable cellularresolution,cross-sectional intravascular imaging will make it possible to study and diagnose human coronary disease with much greater precision in the future.

Persistence of tumor-infiltrating CD8 T cells is tumor-dependent but antigen-independent

How tumor-infiltrating lymphocytes(TILs)that are tumor-specific but functionally tolerant persist in the antigen-expressing tumor tissue is largely unknown.We have previously developed a modified TRansgenic Adenocarcinoma of the Mouse Prostate(TRAMP)model where prostate cancer cells express the T-cell epitope SIYRYYGL(SIY)recognized by CD8 T cells expressing the 2C T-cell receptor(TCR)(referred to as TRP-SIY mice).In TRP-SIY mice,activated 2C T cells rapidly become tolerant following infiltration into the prostate tumor.In this study,we show that tolerant 2C T cells persist in the prostate tumor of TRP-SIY mice by proliferating slowly in a tumor-dependent,but antigen-,interleukin(IL)-7-and IL-15-independent manner.We also show that disappearance of 2C T cells from the lymphoid organs of TRP-SIY mice are due to antigen-induced T-cell contraction rather than altered trafficking or generalized T-cell depletion in the mice.Finally,we show that clonal T cells unreactive to SIY are equally capable of persisting in the prostate tumor.These findings suggest that while functional tolerance of TILs is induced by antigen,persistence of tolerant TILs in the tumor tissue is mediated by a novel mechanism:slow proliferation independent of antigen and homeostatic cytokines.These results also allow CD8 T-cell survival in the tumor environment to be compared with T-cell survival in chronic infection.

Color-selective holographic retroreflector array for sensing applications

Corner cube retroreflectors(CCRs)have applications in sensors,image processing,free space communication and wireless networks.The ability to construct low-loss wavelength filters embedded in CCRs can enable the development of wavelength multiplexing,tunable lasers and photonic integrated circuits.Here we created an~10-μm-thick holographic corner cube retroreflector(HCCR)array that acted as a color-selective wavelength filter and diffracted light at broad angles.Angle-resolved spectral measurements showed that the Bragg peak of the diffracted light from the HCCR array could be tuned from 460 to 545 nm by varying the incident angle.The HCCR array also exhibited a wavelength-selective tuning capability based on the rotation angle in the visible spectrum.HCCRs projected holographic images with the rotational property in the far field.The utility of the HCCR was demonstrated as optical temperature and relative humidity sensors that produced a visible colorimetric response for rapid diagnostics.