The Impact of Sex on Antiplatelet and Anticoagulant Thromboprophylaxis in Patients with Peripheral Artery Disease Post-revascularization.

OBJECTIVE: The aim of this prospective study was to 1) objectively quantify the impact of sex on platelet function in patients with PAD taking antiplatelet and anticoagulant medications and 2) to develop and test a personalized, iterative algorithm which personalizes thromboprophylaxis that incorporates platelet function testing. SUMMARY BACKGROUND DATA: Women with Peripheral Artery Disease (PAD) have worse outcomes as compared to their male counterparts in spite of having lower risk factors. This health disparity may be mitigated by personalizing thromboprophylaxis regimens. METHODS: Patients undergoing revascularization were enrolled. Serial thromboelastography (TEG) and TEG with Platelet Mapping (TEG-PM) was performed up to 6-months post-operatively to determine objective coagulation profiles. In a subset of patients, the Antiplatelet Coagulation Exactness (ACE) algorithm was implemented where patients were iteratively evaluated with TEG and given antiplatelet medications to maintain platelet inhibition at >29%. Statistical analysis was performed using unpaired t-test, ANOVA and Fisher's exact test. RESULTS: One hundred and eighty-one patients met study criteria. 58(32%) patients were females and 123(68%) were males. In the Aspirin cohort, females showed significantly greater clot strength as Maximum Amplitude - Arachidonic Acid (MAAA) and significantly lower platelet inhibition than males: [37.26 vs.32.38, P<0.01] and [52.95% vs.61.65%, P<0.05], respectively. In the Clopidogrel cohort, females showed higher Maximum Amplitude - Adenosine Diphosphate (MAADP) [42.58 vs.40.35, P=NS] compared to males. Females on dual antiplatelet therapy had higher MAADP [39.74 vs.35.07, P=NS] and lower platelet inhibition [45.25% vs.54.99%, P=NS] than males. The incidence of thrombosis of the revascularized segment, defined as thrombotic event, was objectively identified on an arterial duplex. Women showed significantly higher thrombotic events than men [22.95% vs.10.57%, P<0.05] on the same medication. In our pilot study, implementation of the ACE algorithm led to a significant decrease in the thrombosis rate (3%), including non-thrombotic events for females, vs. the historic thrombotic rate (22%) from our institution. CONCLUSIONS: Women with PAD exhibited higher platelet reactivity, clot strength, and reduced platelet inhibition in response to antiplatelet therapy. The use of the ACE algorithm to tailor antiplatelet medication in patients with PAD post-revascularization, resulted in a significant decrease in thrombotic event rates. This may serve as an opportune way to mitigate outcome sex-specific disparities caused by inadequate thromboprophylaxis in women.

Inhaled Adjunct Therapy with Second-Line Drug Candidates for Dose Reduction in Chemotherapeutic Regimens for Multi-drug-Resistant Tuberculosis.

Chemotherapy of multi-drug-resistant tuberculosis (TB) requires prolonged administration of multiple drugs. We investigated whether pulmonary delivery of minute doses of drugs, along with reduced oral doses of the same agents, would affect preclinical efficacy. We prepared dry powder inhalation (DPI) formulations comprising sutezolid (SUT), the second-generation pretomanid analog TBA-354 (TBA), or a fluorinated derivative of TBA-354 (32,625) in a matrix of the biodegradable polymer poly(L-lactide). We established formulation characteristics, doses inhaled by healthy mice, and preclinical efficacy in a mouse model of TB. Oral doses of 100 mg/kg/day or DPI doses of 0.25-0.5 mg/kg/day of drugs SUT, TBA-354, or 32,625 administered over 28 days were sub-optimally effective in reducing lung and spleen burden of Mycobacterium tuberculosis (Mtb) in infected mice. The addition of 0.25-0.5 mg/kg/day of SUT, TBA-354, or 32,625 as DPI to oral doses of 50 mg/kg/day was non-inferior in clearing Mtb from the lungs of infected mice. We concluded that adjunct therapy with inhaled second-line agents has the potential to reduce the efficacious oral dose.

Association between isolated abnormal coagulation profile on transfusion following major surgery: A NSQIP analysis of individuals without bleeding disorders.

INTRODUCTION: Preoperative coagulation screening for patients without bleeding disorders remains controversial. The combinatorial risk of INR, aPTT, and platelet count (PLT) abnormalities leading to bleeding requiring transfusion is not known in these patients. We examined the association between abnormal coagulation profile and the risk of transfusion following common elective surgery in patients without bleeding disorders. STUDY DESIGN AND METHODS: We utilized the National Surgical Quality Improvement Program (NSQIP) database from 2004 to 2018 to identify patients without a history of bleeding disorders undergoing common 23 major elective procedures across 10 specialties. Multivariable logistic regression was used to assess the association between coagulation profile and bleeding requiring packed red blood cell transfusion intra-/post-operatively. RESULTS: Of the 672,075 patients meeting inclusion criteria, 53.7% presented with normal coagulation profile preoperatively. Overall, 12.2% (n = 82,368) received transfusion. In the setting of normal aPTT/PLT, both Equivocal INR of 1.1-1.5 (aOR 1.41, 95% CI 1.38-1.44) and Abnormal INR of >1.5 (aOR 1.81, 95% CI 1.71-1.93) were significantly associated with an increased risk of transfusion. Equivocal (60-70) and Abnormal (>70) aPTT with normal INR/PLT did not demonstrate a comparable risk of transfusion. We observed a synergistic effect of combinatorial lab abnormalities on the risk of transfusion when both Abnormal INR/aPTT and Low PLT of <100,000 were present (aOR 5.18, 95% CI 3.04-8.84), compared to the effect of Abnormal INR/aPTT and normal/elevated PLT (aOR 1.90, 95% CI 1.48-2.45). DISCUSSION: The preoperative presence of abnormal findings in INR or PLT was significantly associated with the risk of bleeding requiring transfusion during intraoperative and postoperative periods.

Preparation and Evaluation of Low-Dose Calcitriol Dry Powder Inhalation as Host-Directed Adjunct Therapy for Tuberculosis.

BACKGROUND: It is unclear whether Vitamin D is efficacious as a host-directed therapy (HDT) for patients of tuberculosis (TB). We investigated pulmonary delivery of the active metabolite of Vitamin D3, i.e., 1, 25-dihydroxy vitamin D3 (calcitriol) in a mouse model of infection with Mycobacterium tuberculosis (Mtb). METHODS: We optimized a spray drying process to prepare a dry powder inhalation (DPI) of calcitriol using a Quality by Design (QbD) approach. We then compared outcomes when Mtb-infected mice were treated with inhaled calcitriol at 5 ng/kg as a stand-alone intervention versus DPI as adjunct to standard oral anti-tuberculosis therapy (ATT). RESULTS: The DPI with or without concomitant ATT markedly improved the morphology of the lungs and mitigated histopathology in both the lungs and the spleens. The number of nodular lesions on the lung surface decreased from 43.7 ± 3.1 to 22.5 ± 3.9 with the DPI alone and to 9.8 ± 2.5 with DPI + ATT. However, no statistically significant induction of host antimicrobial peptide cathelicidin or reduction in bacterial burden was seen with the DPI alone. DPI + ATT did not significantly reduce the bacterial burden in the lungs compared to ATT alone. CONCLUSIONS: We concluded that HDT using the low dose calcitriol DPI contributed markedly to mitigation of pathology, but higher dose may be required to evoke significant induction of bactericidal host response and bactericidal activity in the lung.

Distribution of soil carbon fractions under different bamboo species in northwest Himalayan foothills, India.

Soil carbon and its fractions are important in understanding the mechanism of soil carbon sequestration. The present study evaluated the impact of seven commercial bamboo species, viz., Bambusa balcooa, B. bambos, B. vulgaris, B. nutans, Dendrocalamus hamiltonii, D. stocksii, and D. strictus, on labile and non-labile carbon fractions. In the 0-15-cm layer, B. nutans had the highest very labile C (7.65 g kg-1) followed by B. vulgaris > B. balcooa > D. stocksii > D. hamiltonii > B. bambos > D. strictus > open. The active carbon pool was significantly low under the control plot (i.e. the open) indicating the positive influence of bamboo in soil C build-up in the top 0-15 cm soil layer. Amongst the different species of bamboo evaluated in this study, D. strictus accumulated the highest active C pool in 0-30-cm soil layer followed by B. vulgaris. Of the total organic C in the 0-30 cm soil depth, majority (55-60%) was contributed by the passive C pool comprising the less labile and the non-labile fraction of SOC. A high value of carbon stratification ratio (> 2) was observed for D. strictus, B. bambos, and D. hamiltonii which proves their potential for restoration of the degraded lands. The majority of bamboo species except for B. balcooa and D. stocksii showed a higher carbon management index than open systems, thereby indicating higher rates of soil C rehabilitation. Of the seven bamboo species, B. vulgaris, D. strictus, and B. nutans can be adopted for cultivation in the northwest Himalayas given their ability to positively impact the SOC and its fractions in both surface and sub-surface soil.

Preclinical Development of Inhalable d-Cycloserine and Ethionamide To Overcome Pharmacokinetic Interaction and Enhance Efficacy against Mycobacterium tuberculosis.

We compared the pharmacokinetics and efficacy of a combination of d-cycloserine (DCS) and ethionamide (ETO) via oral and inhalation routes in mice. The plasma half-life (t1/2) of oral ETO at a human-equivalent dose decreased from 4.63 ± 0.61 h to 1.64 ± 0.40 h when DCS was coadministered. The area under the concentration-time curve from 0 h to time t (AUC0-t ) was reduced to one-third. Inhalation overcame the interaction. Inhalation, but not oral doses, reduced the lung CFU/g of Mycobacterium tuberculosis H37Rv from 6 to 3 log10 in 4 weeks, indicating bactericidal activity.

The Pediatric Toronto Extremity Salvage Score (pTESS): Validation of a Self-reported Functional Outcomes Tool for Children with Extremity Tumors.

BACKGROUND: The physical function of children with sarcoma after surgery has not been studied explicitly. This paucity of research is partly because of the lack of a sufficiently sensitive pediatric functional measure. The goal of this study was to establish and validate a standardized measure of physical function in pediatric patients with extremity tumors. QUESTIONS/PURPOSES: (1) What is the best format and content for new upper- and lower-extremity measures of physical function in the pediatric population? (2) Do the new measures exhibit floor and/or ceiling effects, internal consistency, and test-retest reliability? (3) Are the new measures valid? METHODS: In Phase 1, interviews with 17 consecutive children and adolescents with bone tumors were conducted to modify the format and content of draft versions of the pediatric Toronto Extremity Salvage Score (pTESS). In Phase 2, the pTESS was formally translated into French. In Phase 3, 122 participants between 7 and 17.9 years old with malignant or benign-aggressive bone tumors completed the limb-specific measure on two occasions. Older adolescents also completed the adult TESS. Floor and ceiling effects, internal consistency, test-retest reliability, and validity were evaluated. RESULTS: Feedback from interviews resulted in the removal, addition, and modification of draft items, and the pTESS-Leg and pTESS-Arm questionnaires were finalized. Both versions exhibited no floor or ceiling effects and high internal consistency (α > 0.92). The test-retest reliability was excellent for the pTESS-Leg (intraclass correlation coefficient [ICC] = 0.94; 95% CI, 0.90-0.97) and good for the pTESS-Arm (ICC = 0.86; 95% CI, 0.61-0.96). Known-group validity (ability to discriminate between groups) was demonstrated by lower mean pTESS-Leg scores for participants using gait aids or braces (mean = 68; SD = 21) than for those who did not (mean = 87; SD = 11; p < 0.001). There was no significant difference between pTESS arm scores among respondents using a brace (n = 5; mean = 73; SD = 11) and those without (n = 22; mean = 83; SD = 19; p = 0.13). To evaluate construct validity, we tested a priori hypotheses. The duration since chemotherapy correlated moderately with higher pTESS-Leg scores (r = 0.4; p < 0.001) but not with pTESS-Arm scores (r = 0.1; p = 0.80), and the duration since tumor resection correlated moderately with higher pTESS-Leg scores (r = 0.4; p < 0.001) but not pTESS-Arm scores (r = 0.2; p = 0.4). Higher VAS scores (that is, it was harder to do things) antecorrelated with both pTESS versions (pTESS-Leg: r = -0.7; p < 0.001; pTESS-Arm: r = -0.8; p < 0.001). To assess criterion validity, we compared the pTESS with the current "gold standard" (adult TESS). Among adolescents, strong correlations were observed between the TESS and pTESS-Leg (r = 0.97, p < 0.001) and pTESS-Arm (r = 0.9, p = 0.007). CONCLUSIONS: Both pTESS versions exhibited no floor or ceiling effects and had high internal consistency. The pTESS-Leg demonstrated excellent reliability and validity, and the pTESS-Arm demonstrated good reliability and reasonable validity. The pTESS is recommended for cross-sectional evaluation of self-reported physical function in pediatric patients with bone tumors. LEVEL OF EVIDENCE: Level II, outcome measurement development.

Magnetic resonance imaging characteristics of lesions relate to the difficulty of peripheral arterial endovascular procedures.

OBJECTIVE: Limitations with current peripheral arterial imaging modalities make selection of patients for percutaneous vascular interventions difficult. The purpose of this study was to determine whether a novel preprocedural magnetic resonance imaging (MRI) method can identify lesions that would be more challenging to cross during percutaneous vascular intervention. METHODS: Fourteen patients with peripheral arterial disease underwent MRI before their intervention. A novel steady-state free precession flow-independent magnetic resonance (MR) angiogram was used to locate lesions, and an ultrashort echo time image was used to characterize hard lesion components including calcium and dense collagen. Lesions were characterized as hard if ≥50% of the lumen was occluded with calcium or collagen (as determined by MR image characteristics) in the hardest cross section within the lesion. The primary outcome was the time it took to cross a guidewire through the target lesion. The secondary outcome was the need for stenting. RESULTS: Of 14 lesions, 8 (57%) were defined as hard and 6 (43%) were soft on the basis of MR image characteristics. Hard lesions took significantly longer to cross than soft lesions (average, 14 minutes 49 seconds vs 2 minutes 17 seconds; P = .003). Hard lesions also required stenting more often than soft lesions (Fisher exact test, P = .008). Of 14 lesions, 2 (14%) could not be crossed with a guidewire, and both lesions were hard. MR images also detected occult patencies and noncalcified hard lesions that could not be seen on X-ray angiography. CONCLUSIONS: MRI can be used to determine which peripheral arterial lesions are more difficult to cross with a guidewire. Future work will determine whether MRI lesion characterization can predict long-term endovascular outcomes to aid in procedure planning.

Perfusion measures for symptom severity and differential outcome of revascularization in limb ischemia: Preliminary results with arterial spin labeling reactive hyperemia.

BACKGROUND: Previously, a theoretical model based on microvascular physiology was established to facilitate the interpretation of calf perfusion dynamics recorded by arterial spin labeling (ASL). PURPOSE: To investigate the clinical relevance of novel perfusion indices by comparing them to the symptoms, response to revascularization, and short-term functional outcome in patients with peripheral arterial disease (PAD). STUDY TYPE: Prospective cohort study. POPULATION: Nineteen patients with PAD. FIELD STRENGTH/SEQUENCE: Pulsed ASL at 3T. ASSESSMENT: The mid-calf reactive hyperemia induced by 2 minutes of arterial occlusion was recorded in PAD patients. The perfusion responses were characterized by the peak, time-to-peak, and physiological model-derived indices including the baseline perfusion fr , arterial resistance Ra , and compliance Ca , and sensitivity gATP and response time τATP of downstream microvasculature to metabolic stress. These indices were compared to the disease severity and outcome within 6 months after revascularization assessed by self-reported symptoms and the ankle-brachial index. Disease severity was categorized as asymptomatic, claudication, or critical limb ischemia. The outcome was categorized as symptom resolved or limited improvement. STATISTICAL TESTS: Severity and outcome groups were compared using Mann-Whitney and Kruskal-Wallis tests with Holm-Sidak adjustments. RESULTS: The peak perfusion decreased and model arterial resistance increased progressively with increasing severity of limb ischemia (P = 0.0402 and 0.0413, respectively). Eleven patients had a successful endovascular procedure, including six patients who had symptoms resolved, four patients who had remaining leg pain, and one patient lost to follow-up. The subjects with limited improvement had significantly lower preintervention microvascular sensitivity gATP than those with symptoms resolved (8.72 ± 1.46 vs. 4.93 ± 0.91, P = 0.0466). DATA CONCLUSION: ASL reactive hyperemia reflects multiple aspects of the pathophysiology. Measures of macrovascular arterial disease are related to the manifested symptom severity, whereas preintervention gATP associated with microvascular dysfunction is related to prognosis following revascularization. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 4 J. Magn. Reson. Imaging 2018;47:1578-1588.

MRI for peripheral artery disease: Introductory physics for vascular physicians.

Magnetic resonance imaging (MRI) has advanced significantly in the past decade and provides a safe and non-invasive method of evaluating peripheral artery disease (PAD), with and without using exogenous contrast agents. MRI offers a promising alternative for imaging patients but the complexity of MRI can make it less accessible for physicians to understand or use. This article provides a brief introduction to the technical principles of MRI for physicians who manage PAD patients. We discuss the basic principles of how MRI works and tailor the discussion to how MRI can evaluate anatomic characteristics of peripheral arterial lesions.

Puncturing Plaques.

PURPOSE: To test and validate magnetic resonance imaging (MRI) sequences for peripheral artery lesion characterization and relate the MRI characteristics to the amount of force required for a guidewire to puncture peripheral chronic total occlusions (CTOs) as a surrogate for immediate failure of endovascular therapy. METHODS: Diseased superficial femoral, popliteal, and tibial artery segments containing 55 atherosclerotic lesions were excised from the amputated limbs of 7 patients with critical limb ischemia. The lesions were imaged at high resolution (75 µm3 voxels) with T2-weighted (T2W) and ultrashort echo time (UTE) sequences on a 7-T MR scanner. The MR images (n=15) were validated with micro-computed tomography and histology. CTOs (n=40) were classified by their MR signal characteristics as "soft" (signals indicating fat, thrombus, microchannels, or loose fibrous tissue), "hard" (collagen and/or speckled calcium signals), or "calcified" (calcified nodule signals). A 2-kg load cell advanced the back end of a 0.035-inch stiff guidewire at a fixed displacement rate (0.05 mm/s) through the CTOs, and the forces required to cross each lesion were measured. RESULTS: T2W images showed fat as hyperintense and hardened tissue as hypointense. Calcium and thrombus appeared as a signal void in conventional MRI sequences but were easily identified in UTE images (thrombus was hyperintense and calcium hypointense). MRI accurately differentiated "hard," "soft," and "calcified" CTOs based on associated guidewire puncture force. The guidewire could not enter "calcified" CTOs (n=6) at all. "Hard" CTOs (n=9) required a significantly higher (p<0.001) puncture force of 1.71±0.51 N vs 0.43±0.36 N for "soft" CTOs (n=25). CONCLUSION: MRI characteristics of PAD lesions correlate with guidewire puncture forces, an important aspect of crossability. Future work will determine if clinical MR scanners can be used to predict success in peripheral vascular interventions.

Unsupervised classification of multi-contrast magnetic resonance histology of peripheral arterial disease lesions using a convolutional variational autoencoder with a Gaussian mixture model in latent space: A technical feasibility study.

PURPOSE: To investigate the feasibility of a deep learning algorithm combining variational autoencoder (VAE) and two-dimensional (2D) convolutional neural networks (CNN) for automatically quantifying hard tissue presence and morphology in multi-contrast magnetic resonance (MR) images of peripheral arterial disease (PAD) occlusive lesions. METHODS: Multi-contrast MR images (T2-weighted and ultrashort echo time) were acquired from lesions harvested from six amputated legs with high isotropic spatial resolution (0.078 mm and 0.156 mm, respectively) at 9.4 T. A total of 4014 pseudo-color combined images were generated, with 75% used to train a VAE employing custom 2D CNN layers. A Gaussian mixture model (GMM) was employed to classify the latent space data into four tissue classes: I) concentric calcified (c), II) eccentric calcified (e), III) occluded with hard tissue (h) and IV) occluded with soft tissue (s). Test image probabilities, encoded by the trained VAE were used to evaluate model performance. RESULTS: GMM component classification probabilities ranged from 0.92 to 0.97 for class (c), 1.00 for class (e), 0.82-0.95 for class (h) and 0.56-0.93 for the remaining class (s). Due to the complexity of soft-tissue lesions reflected in the heterogeneity of the pseudo-color images, more GMM components (n=17) were attributed to class (s), compared to the other three (c, e and h) (n=6). CONCLUSION: Combination of 2D CNN VAE and GMM achieves high classification probabilities for hard tissue-containing lesions. Automatic recognition of these classes may aid therapeutic decision-making and identifying uncrossable lesions prior to endovascular intervention.

Magnetic Resonance Imaging and Histological Insights Into Deep Venous Arterialisation.

Introduction: Percutaneous deep venous arterialisation (DVA) is emerging as a promising alternative for limb salvage in chronic limb threatening ischaemia (CLTI) patients without any reasonable anatomical option for conventional revascularisation techniques. However, its mechanism of action remains incompletely understood. This report aimed to find some of the histological alterations occurring in the limb following DVA. Report: This short report presents the case of a 53 year old female who underwent DVA for Rutherford 5 CLTI. Although the intervention was successful and showed evidence of improved blood flow to the foot, the post-operative course was notable due to worsening infection leading to a below knee amputation four weeks later. The blood vessels were harvested for histological analysis, which found features of venous arterialisation such as smooth muscle cell proliferation and neointimal hyperplasia, even in the paired posterior tibial vein that did not undergo DVA. Discussion: This case demonstrated unexpected histological changes occurring in the paired posterior tibial vein that did not undergo DVA. This warrants further investigations to fully understand the mechanisms at play in DVA and to explore the role of the paired vein in sustaining arterialised flow to the foot.

Optimizing the fabrication of electrospun nanofibers of prochlorperazine for enhanced dissolution and permeation properties.

Despite being an approved antiemetic for more than five decades, the clinical usefulness of prochlorperazine is limited by its low solubility and inconsistent absorption in the gastrointestinal tract, which presents challenges for nanotherapeutic interventions. Here, we report the preparation of a highly soluble and permeable nanofiber formulation of prochlorperazine using the Quality-by-Design approach. The final nanofiber formulation with drug entrapment of 88.02 ± 1.14 % was obtained at 20.0 kV, with a flow rate of 0.5 ml/h and tip-to-collector distance of 19.9 cm. Physio-mechanical properties, such as thickness (0.42 ± 0.02 mm), pH resistance (7.04 ± 0.08), folding endurance (54 ± 5), and tensile strength (0.244 ± 0.02 N.mm-2), were appropriate for packaging and application to oromucosal surfaces. The content uniformity (93.48-106.63 %) and weight variation (<1.8 mg) of the optimal nanofiber formulation were within the permissible limits prescribed for orodispersible films. Microscopical investigations confirm a randomly deposited and dense network of woven nanofibers with an average diameter of 363 ± 5.66 nm. The drug particles were embedded homogeneously on the fiber in the nanoform (4.27 ± 1.34 nm). The spectral analysis using TEM-EDS shows diffraction peaks of sulfur and chlorine, the elemental constituents of prochlorperazine. The drug was amorphized in the nanofiber formulation, as led by the decline of the crystallinity index from 87.25 % to 7.93 % due to electrostatic destabilization and flash evaporation of the solvent. The enthalpy of fusion values of the drug in the nanofiber mat decreased significantly to 23.6 J/g compared to its pristine form, which exhibits a value of 260.7 J/g. The nanofibers were biocompatible with oral mucosal cells, and there were no signs of mucosal irritation compared to 1 % sodium lauryl sulfate. The fiber mats rapidly disintegrated within <1 s and released ≈91.49 ± 2.1 % of the drug within 2 min, almost 2-fold compared to the commercial Stemetil MD® tablets. Similarly, the cumulative amount of the drug permeated across the unit area of the oromucosal membrane was remarkably high (31.28 ± 1.30 µg) compared to 10.17 ± 1.11 µg and 13.10 ± 1.79 µg from the cast film and drug suspension. Our results revealed these nanofiber formulations have the potential to be fast-dissolving oromucosal delivery systems, which can result in enhanced bioavailability with an early onset of action due to rapid disintegration, dissolution, and permeation.

Transcriptional regulation of suppressors of cytokine signaling during infection with Mycobacterium tuberculosis in human THP-1-derived macrophages and in mice.

Mycobacterium tuberculosis (Mtb) infection leads to upregulation of Suppressors of Cytokine signaling (SOCS) expression in host macrophages (Mϕ). SOCS proteins inhibit cytokine signaling by negatively regulating JAK/STAT. We investigated this host-pathogen dialectic at the level of transcription. We used phorbol-differentiated THP-1 Mϕ infected with Mtb to investigate preferential upregulation of some SOCS isoforms that are known to inhibit signaling by IFN-γ, IL-12, and IL-6. We examined time kinetics of likely transcription factors and signaling molecules upstream of SOCS transcription, and survival of intracellular Mtb following SOCS upregulation. Our results suggest a plausible mechanism that involves PGE2 secretion during infection to induce the PKA/CREB axis, culminating in nuclear translocation of C/EBPß to induce expression of SOCS1. Mtb-infected Mϕ secreted IL-10, suggesting a mechanism of induction of STAT3, which may subsequently induce SOCS3. We provide evidence of temporal variation in SOCS isoform exspression and decay. Small-interfering RNA-mediated knockdown of SOCS1 and SOCS3 restored the pro-inflammatory milieu and reduced Mtb viability. In mice infected with Mtb, SOCS isoforms persisted across Days 28-85 post infection. Our results suggest that differential temporal regulation of SOCS isoforms by Mtb drives the host immune response towards a phenotype that facilitates the pathogen's survival.

Peripheral arterial disease treatment planning using noninvasive and invasive imaging methods.

With the growing prevalence and mortality of peripheral arterial disease, preoperative assessment, risk stratification, and determining the correct indication for endovascular and open surgical procedures are essential for therapeutic decision-making. The effectiveness of interventional procedures is significantly influenced by the plaque composition and calcification pattern. Therefore, the identification of patients for whom endovascular treatment is the most appropriate therapeutic solution often remains a challenge. The most commonly used imaging techniques have their own limitations and do not provide findings detailed enough for specific, personalized treatment planning. Using state-of-the-art noninvasive and invasive imaging modalities, it is now possible to obtain a view, not only of the complex vascular anatomy and plaque burden of the lower extremity arterial system, but also of complex plaque structures and various pathologic calcium distribution patterns. In the future, as these latest advancements in diagnostic methods become more widespread, we will be able to obtain more accurate views of the plaque structure and anatomic complexity to guide optimal treatment planning and device selection. We reviewed the implications of the most recent invasive and noninvasive lower extremity imaging techniques and future directions.

Human Cadaveric Model for Vessel Preparation Device Testing in Calcified Tibial Arteries.

To describe an ex vivo model for vessel preparation device testing in tibial arteries. We performed orbital atherectomy (OA), intravascular lithotripsy (IVL), and plain balloon angioplasty (POBA) on human amputated limbs with evidence of concentric tibial artery calcification. The arterial segments were then harvested for ex vivo processing which included imaging with microCT, decalcification, and histology. The model was tested out in 15 limbs and was successful in 14 but had to be aborted in 1/15 case due to inability to achieve wire access. A total of 22 lesions were treated with OA on 3/22 lesions, IVL on 8/22, and POBA without vessel preparation on the remaining 11/22. Luminal gain was assessed with intravascular ultrasound and histology was able to demonstrate plaque disruption, dissections, and cracks within the calcified lesions. A human cadaveric model using amputated limbs is a feasible, high-fidelity option for evaluating the performance of vessel preparation devices in calcified tibial arteries.

Scoping review of atherectomy and intravascular lithotripsy with or without balloon angioplasty in below-the-knee lesions.

Objective: We evaluated how contemporary data on infrapopliteal vessel preparation have been reported to identify knowledge gaps and opportunities for future research. Methods: A literature search was performed on Web of Science, PubMed, and Google Scholar to identify clinical research studies reporting on the outcomes of vessel preparation in below-the-knee lesions between 2006 and 2021. Studies were excluded if they were case reports or case series with a sample size of <10. Results: A total of 15 studies comprising 5450 patients were included in this review, with vessel preparation performed in 2179 cases (40%). Of the 15 studies, 2 were randomized controlled trials, 6 were prospective cohort studies, and 7 were retrospective studies. Only 2 of the 15 studies evaluated intravascular lithotripsy devices, and 6 were noncomparative studies. The mean diameter stenosis treated was 86.7% ± 12.6%, and the lesion length was 71.7 ± 55.3 mm. Large heterogeneity was found in the choice and definitions of end points and lesion characterization. Procedural success ranged between 84% and 90%, and bailout stenting was performed in 0.8% to 15% of cases. Of the five studies comparing procedural success of atherectomy with or without balloon angioplasty to balloon angioplasty alone, only one was in favor of the former (99% vs 90%; P < .001). The remaining studies did not show any statistically significant differences. Similarly, atherectomy had a significantly superior limb salvage rate in only one of seven studies (91% vs 73%; P = .036). In contrast, the seven studies evaluating target lesion revascularization reported conflicting outcomes, with two in favor of atherectomy, two against atherectomy, and three reporting similar outcomes between atherectomy and balloon angioplasty alone. None of the studies evaluating intravascular lithotripsy was comparative. Conclusions: The current body of evidence on vessel preparation in tibial arteries is largely based on observational studies with a large amount of heterogeneity and a number of inconsistencies. Further clinical and experimental studies with more robust study designs are warranted to investigate the comparative efficacy and safety of vessel preparation in calcified tibial arteries.

Automatic Classification of Magnetic Resonance Histology of Peripheral Arterial Chronic Total Occlusions Using a Variational Autoencoder: A Feasibility Study.

The novel approach of our study consists in adapting and in evaluating a custom-made variational autoencoder (VAE) using two-dimensional (2D) convolutional neural networks (CNNs) on magnetic resonance imaging (MRI) images for differentiate soft vs. hard plaque components in peripheral arterial disease (PAD). Five amputated lower extremities were imaged at a clinical ultra-high field 7 Tesla MRI. Ultrashort echo time (UTE), T1-weighted (T1w) and T2-weighted (T2w) datasets were acquired. Multiplanar reconstruction (MPR) images were obtained from one lesion per limb. Images were aligned to each other and pseudo-color red-green-blue images were created. Four areas in latent space were defined corresponding to the sorted images reconstructed by the VAE. Images were classified from their position in latent space and scored using tissue score (TS) as following: (1) lumen patent, TS:0; (2) partially patent, TS:1; (3) mostly occluded with soft tissue, TS:3; (4) mostly occluded with hard tissue, TS:5. Average and relative percentage of TS was calculated per lesion defined as the sum of the tissue score for each image divided by the total number of images. In total, 2390 MPR reconstructed images were included in the analysis. Relative percentage of average tissue score varied from only patent (lesion #1) to presence of all four classes. Lesions #2, #3 and #5 were classified to contain tissues except mostly occluded with hard tissue while lesion #4 contained all (ranges (I): 0.2-100%, (II): 46.3-75.9%, (III): 18-33.5%, (IV): 20%). Training the VAE was successful as images with soft/hard tissues in PAD lesions were satisfactory separated in latent space. Using VAE may assist in rapid classification of MRI histology images acquired in a clinical setup for facilitating endovascular procedures.