A case of pseudo-Kaposi sarcoma with chronic limb-threatening ischemia.

BACKGROUND: Pseudo-Kaposi sarcoma (PKS) is a rare vascular proliferative disease, caused by arteriovenous malformation (AVM) and chronic venous insufficiency. The lesions are characterized by purple or reddish-brownish papules, plaques, and nodules. Although benign, it is clinically similar to Kaposi's sarcoma (KS), a malignant disease, and must be differentiated by histopathological examination. We report a rare case of PKS with chronic limb-threatening ischemia (CLTI). CASE PRESENTATION: An 83-year-old man with diabetes mellitus (DM) presented to a local dermatology department with a complaint of a right second toe ulcer and was, thereby, referred to our department due to arterial bleeding during skin biopsy to exclude malignant diseases. Although the pulsation of dorsalis pedis artery of the affected limb was palpable, the skin perfusion pressure was only 20 and 30 mmHg on the dorsum and planter surface, respectively, indicating severe ischemia of toe and forefoot. Ultrasonography and computed tomography revealed an AVM around the right second metatarsophalangeal joint and occlusion of the right dorsalis pedis artery in the middle, indicating CLTI in the background. Pathological findings of the skin biopsy found capillary blood vessel proliferation, hemosiderin deposition, and extravascular red blood cell leakage in the dermal layer, which could be found in KS. However, CD34 was normally stained in the vascular endothelium, and human herpesvirus-8 staining was negative, resulting in the pathological diagnosis of PKS, a proliferative vascular lesion associated with AVM. The ulcer was spontaneously epithelialized, but 2 years later the ulcer recurred and infection developed, necessitating treatment for abnormal blood flow. Transarterial embolization using N-butyl 2-cyanoacrylate for the AVM controlled abnormal perfusion once; however, the procedure exacerbated perfusion of the toe, resulting in foot ulcer progression. Forefoot amputation with surgical excision of AVM was performed, and thereby, wound healing was achieved. CONCLUSION: This is a rare case of PKS with CLTI complicated with AVM. As there is currently no established consensus on the treatment of PKS, the approach to treatment strategy should be tailored to the specific condition of each patient.

New high-throughput screening method for Chinese hamster ovary cell lines expressing low reduced monoclonal antibody levels: application of a system controlling the gas phase over cell lysates in miniature bioreactors and facilitating multiple sample setup.

Interchain disulfide bonds in monoclonal antibodies may be reduced during large-scale mAb production using Chinese hamster ovary (CHO) cells. This reaction lowers the mAb product yield and purity; however, it may be prevented by screening cell lines that are unsusceptible to reduction and using them in mAb production. Antibody reduction susceptibility may be cell line-dependent. To the best of our knowledge, however, an efficient method of screening reduction-unsusceptible CHO cell lines has not been previously reported. Here, we report a novel screening method that can simultaneously detect and identify mAb reduction susceptibility in lysates containing ≤ 48 CHO cell lines. This evaluation system was equally effective and generated similar results at all culture scales, including 250 mL, 3 L, and 1000 L. Furthermore, we discovered that reduction-susceptible cell lines contained higher total intracellular nicotinamide adenine dinucleotide phosphate (NADPH) and NADP+ concentrations than reduction-unsusceptible cell lines, regardless of whether they expressed immunoglobulin (Ig)G4 or IgG1. NADPH or NADP+ supplementation in the lysate of reduction-unsusceptible cells resulted in mAb reduction. Application of the innovative CHO cell line screening approach could mitigate or prevent reductions in large-scale mAb generation from CHO cells.

A case of lymphoma mimicking infected internal iliac artery aneurysm.

BACKGROUND: Malignant lymphoma rarely mimics an infected arterial aneurysm and a ruptured arterial aneurysm because of similar imaging findings, leading to misdiagnosis. The hematomas of ruptured aneurysms are radiologically difficult to distinguish from those of malignant lymphoma in emergency settings. Hence, a definitive diagnosis is crucial to avoid unnecessary surgery. CASE PRESENTATION: A man in his 80s with hematuria and shock vital had right internal iliac artery aneurysm (IIAA) and perianeurysmal fluid retention, which appeared to be a ruptured or an infected aneurysm. Treatment was initiated for infected IIAA instead of for ruptured IIAA. Systemic inflammatory response syndrome developed, and the infectious sources were assessed. Pacemaker lead and urinary tract infections were identified and treated; however, blood pressure was unstable. The aneurysm was treated with endovascular aortic aneurysm repair following antibiotic therapy; however, fluid retention increased, and inflammatory status and hematuria deteriorated. Open surgical conversion was performed to manage the infected lesions. Although an iliopsoas abscess was detected during surgery and nephrectomy and ureterectomy were performed to control the hematuria, analysis of the removed tissues led to the pathological diagnosis of diffuse large B-cell lymphoma (DLBCL). CONCLUSIONS: We encountered a case of DLBCL with imaging findings mimicking an infected internal iliac artery aneurysm, and definitive diagnosis was made more than 2 months after the initial examination. Definitively diagnosing malignant lymphoma around an iliac artery aneurysm based merely on symptoms and imaging findings is extremely difficult. Thus, histological examination should be actively performed in atypical infected aneurysms.

Lateral approach to distal peroneal artery without fibular resection.

Bypass to the peroneal artery has sometimes been effective for pedal gangrene. However, the difficulty of approaching the terminal segment of the peroneal artery because of its anatomic features has been a clinical issue. Surgical access to this area can be achieved via a lateral approach with fibular resection. Although severe complications associated with fibular resection have rarely been reported, a less invasive surgical procedure would enable faster postoperative recovery and reduce the incidence of wound-related complications. We have described our experience with successful terminal peroneal artery bypass via a lateral approach without fibular resection in a 38-year-old male patient with chronic limb-threatening ischemia.

[A case of localized fasciitis with ulcerative colitis].

A 36-year-old man with ulcerative colitis presented with bloody stools at the beginning of October 2020. His condition had been stable without treatment since diagnosis 4 years prior. He was administered 4,000 mg of salazosulfapyridine orally and the bloody stools resolved. Fifteen days after treatment, he was admitted to our hospital with swelling and pain in his right lower leg. Laboratory results revealed an elevated erythrocyte sedimentation rate (43 mm/hr) and mildly elevated C-reactive protein levels (4.08 mg/dl). His D-dimer level was also elevated at 7.6 µg/ml. MRI using fat saturated T2-weighted imaging demonstrated marked hyperintensity in the fascia of the lower leg flexor and blood vessels of interstitial. In gadolinium-enhanced T1-weighted images, the deep veins were found to be dilated and the vein walls and their surrounding areas strongly contrasted, suggestive of localized fasciitis. No abnormalities were found on biopsy of his right gastrocnemius muscle on the 5th day after admission. Two days after the muscle biopsy, the patient began experiencing swelling and pain in his left lower leg. The high intensity lesions in his right leg were reduced on MRI performed the same day, but that of the fascia between the left gastrocnemius and soleus muscles was noted. We administered 60 mg (1.0 mg/kg/day) of prednisolone orally on day 9 and the pain and swelling in both legs promptly resolved. The prednisolone was tapered to 5 mg/day and as of the time of writing, resolution of pain and swelling has been maintained. Gastrocnemius myalgia syndrome, which causes pain and localized fasciitis, is often reported as a complication of Crohn's disease but is rare in conjunction with ulcerative colitis. It is important that clinicians are aware of this syndrome so it can be recognized early and successfully treated.

The Impact of Chronic Limb-Threatening Ischemia on Cardiac Surgery.

Purpose: The effect of chronic limb threatening ischemia (CLTI) on advanced cardiac disease, which requires surgical treatment, has rarely been reported. The purpose of this study was to review the outcomes of cardiac surgery in patients with CLTI and determine the risk factors, with a particular focus on the severity of CLTI. Patients: The baseline characteristics and outcomes of 33 patients who were treated for CLTI and underwent cardiac surgery were retrospectively analyzed. The states of CLTI were evaluated based on the Wound, Ischemia, and foot Infection (WIfI) classification system, and 33 patients were divided into the low-WIfI group (stages 1-2, n = 13) and high-WIfI group (stages 3-4, n = 20). Results: The in-hospital mortality rate was 0% in low-WIfI group and 35% in high-WIfI group (p = 0.027). Postoperative complications, particularly severe infections, occurred more frequently among high-WIfI group than low-WIfI group (70.0% vs. 23.1%, p < 0.01). Multivariable analysis identified foot infection grade as a WIfI classification factor and lower albumin levels as factors significantly associated with postoperative complications. The 1-year and 2-year survival rates were 84.6% and 67.7% in low-WIfI group and 45% and 28.1% in high-WIfI group, respectively (p = 0.011). Conclusions: Cardiac surgery in patients with high WIfI stage was an extremely high-risk procedure. In such patients, lowering the WIfI stage by lower extremity revascularization and/or debridement of diseased parts prior to cardiac surgery can be considered.

Successful endovascular therapy involving direct puncture for spontaneous internal iliac artery aneurysm rupture.

Neurofibromatosis type 1 (NF-1) is associated with fatal vascular complications. A 40-year-old woman with NF-1 who had previously undergone left iliac artery ligation and femorofemoral bypass grafting for internal iliac artery (IIA) aneurysm rupture was transported to our hospital for the treatment of a newly developed IIA aneurysm. Although endovascular therapy was difficult owing to the previous surgery, we successfully performed embolization of the aneurysm and its feeding vessels via direct percutaneous puncture under ultrasound guidance. Aneurysm enhancement had completely disappeared at 2 months postoperatively. We have reported a novel approach of direct percutaneous puncture for IIA aneurysm embolization in a patient with NF-1.

Virus clearance by activated carbon for therapeutic monoclonal antibody purification.

In our previous study, activated carbon (AC) was employed in the purification process of therapeutic monoclonal antibody (mAb) as a replacement for Protein A affinity chromatography. In addition, we established an innovative column-free flow-through purification process using AC filter. In these investigations, the effective clearance of impurities (high-molecular-weight species, low-molecular-weight species, host cell proteins, and DNA) was observed compared to the conventional Protein A platform purification process. In this study, virus removal capability of our established AC process (AC filter) was investigated using two model viruses, Murine Leukemia Virus (MuLV) and Minute Virus of Mice (MVM) with the combination of two filtration methods (single-pass filtration and re-circulation filtration) using three kinds of mAbs. We found effective clearance of both MuLV and MVM (>3 log reduction factor, LRF) in all mAbs. Not only filtration method but also re-circulation duration didn't affect LRF, and >3 LRF of virus removal could be achieved by only single-pass filtration. From these results, it is expected that AC will be a promising candidate for the virus removal unit operation for mAb purification processes.

Calcified amorphous tumor located on a severely calcified mitral annulus in a patient with normal renal function.

A calcified amorphous tumor (CAT) of the heart is a rare, nonneoplastic, intracavitary cardiac mass. Histological examination shows that it contains calcified and amorphous fibrous material with underlying chronic inflammation. Surgical excision is generally recommended to avoid future embolism. The risk of embolism has been reported to be especially high in mitral-annular-calcification-related CAT, which constitutes a subgroup of CAT that is often associated with end-stage renal disease. A case of a CAT attached to the anterior annulus of the mitral valve that was easily removed with a light touch of the forceps through aortotomy is reported.

Challenges for the Development of Extracellular Vesicle-Based Nucleic Acid Medicines.

Nucleic acid drugs, such as siRNAs, antisense oligonucleotides, and miRNAs, exert their therapeutic effects by causing genetic changes in cells. However, there are various limitations in their delivery to target organs and cells, making their application to cancer treatment difficult. Extracellular vesicles (EVs) are lipid bilayer particles that are released from most cells, are stable in the blood, and have low immunogenicity. Methods using EVs to deliver nucleic acid drugs to target organs are rapidly being developed that take advantage of these properties. There are two main methods for loading nucleic acid drugs into EVs. One is to genetically engineer the parent cell and load the target gene into the EV, and the other is to isolate EVs and then load them with the nucleic acid drug. Target organ delivery methods include passive targeting using the enhanced permeation and retention effect of EVs and active targeting in which EVs are modified with antibodies, peptides, or aptamers to enhance their accumulation in tumors. In this review, we summarize the advantages of EVs as a drug delivery system for nucleic acid drugs, the methods of loading nucleic acid drugs into EVs, and the targeting of EVs to target organs.

Clinical Application of Laser Speckle Flowgraphy to Assess Changes in Blood Flow to the Foot After a Lumbar Sympathetic Ganglion Block: A Case Report.

BACKGROUND: The lumbar sympathetic ganglion block (LSGB) has been used as a diagnostic and therapeutic procedure for treating pain conditions such as neuropathic and ischemia-related pain, affecting the lower extremities. In general, an increase in skin temperature is useful in confirming the effectiveness of the sympathetic nerve block in clinical settings. However, the assessment of skin temperature in patients with peripheral arterial disease (PAD) occasionally provides false negatives. CASE PRESENTATION: A novel technology, laser speckle flowgraphy (LSFG) enables noninvasive quantitative and qualitative blood flow assessments. LSFG is a novel neuro-monitor for quantitative blood flow detection in the optic nerve head during cardiac surgery. Herein, we report on measuring foot blood flow using LSFG before and after LSGB in a PAD patient. This research aimed to determine whether LSFG could detect any improvement in the dynamics of foot blood flow after an LSGB in a situation where changes in skin temperature alone could not determine the procedure's outcome. CONCLUSION: LSFG can be used to assess blood flow changes in a foot with PAD, following a LSGB.

A Case of Isolated Infragenicular Arterial Lesions Successfully Treated with Open Endarterectomy.

A 68-year-old man with a history of superior mesenteric arterial thromboembolism due to chronic atrial fibrillation had experienced intermittent claudication (IC) of his left leg for 3 years. Computed tomography angiography showed focal occlusive lesions in the left distal popliteal artery and proximal segments of the infrapopliteal arteries. Endarterectomy was performed for these localized arterial lesions, and a drastic symptomatic improvement of IC after revascularization was achieved. The endarterectomized segments remained patent for 4 years after the surgery. Endarterectomy could be a useful alternative to bypass surgery and endovascular therapy for the treatment of localized infragenicular arterial lesions.

Collateral artery bypass in the infrapopliteal segment.

A 74-year-old man with diabetes and end-stage renal failure on regular dialysis required revascularization for gangrene of multiple toes and a heel ulcer on the right foot with chronic limb-threatening ischemia. However, the anterior tibial artery, posterior tibial artery, and peroneal artery, which are the usual targets below the knee, showed obstruction or calcification and were considered inappropriate bypass targets. Instead, a collateral artery developed along the area of the posterior tibial artery, and bypass surgery was performed with this artery. This is a case report showing successful collateral artery bypass grafting in the distal infrapopliteal segment.

Predictive Model for Postoperative Ambulatory Function after Lower Extremity Bypass in Chronic Limb-Threatening Ischemia.

BACKGROUND: In chronic limb-threatening ischemia, maintenance or recovery of ambulatory function is an important goal of treatment. This study aimed to develop a predictive model for ambulatory ability 1 year after bypass based on preoperative risk factors, including the Wound, Ischemia, and foot Infection (WIfI) classification. METHODS: We analyzed 146 patients with chronic limb-threatening ischemia (154 limbs) who underwent bypass to below the knee arteries. The patients were classified into 2 groups based on ambulatory status 1 year postoperatively: postoperative ambulation (99 patients, 104 limbs) and postoperative nonambulation (47 patients, 50 limbs). Various factors associated with postoperative ambulation were analyzed and a predictive model of postoperative ambulation was developed. RESULTS: Multivariate logistic regression analysis detected preoperative nonambulatory status, functional nonindependence in daily living, older age, WIfI wound grade 3, chronic obstructive pulmonary disease, and hemodialysis as independent risk factors for postoperative nonambulation. The predictive scoring model (scores ranging from -5.0 to 4.4) comprising these risk factors discriminated the postoperative ambulatory status well: the probabilities of postoperative ambulatory ability were ≥85% in those with a score ≤-2, 50% in those with a score of zero, and ≤15% in those with a score ≥2. The area under the receiver operating characteristic curve was 0.898, indicating good performance of the model. CONCLUSIONS: Preoperative nonambulatory status, functional nonindependence, advanced age, high WIfI wound grade, chronic obstructive pulmonary disease, and hemodialysis were important predictors of postoperative nonambulatory status. The predictive model will help us identify patients who will benefit from bypass surgery.

Extracellular Vesicles Are Key Regulators of Tumor Neovasculature.

Tumor progression involves a series of biologically important steps in which the crosstalk between cancer cells and the surrounding environment is an important issue. Angiogenesis is a key tumorigenic phenomenon for cancer progression. Tumor-related extracellular vesicles (EVs) modulate the tumor microenvironment (TME) through cell-to-cell communication. Tumor cells in a hypoxic TME release more EVs than cells in a normoxic environment due to uncontrollable tumor proliferation. Tumor-derived EVs in the TME influence endothelial cells (ECs), which then play multiple roles, contributing to tumor angiogenesis, loss of the endothelial vascular barrier by binding to ECs, and subsequent endothelial-to-mesenchymal transition. In contrast, they also indirectly induce tumor angiogenesis through the phenotype switching of various cells into cancer-associated fibroblasts, the activation of tumor-associated ECs and platelets, and remodeling of the extracellular matrix. Here, we review current knowledge regarding the involvement of EVs in tumor vascular-related cancer progression.

NT5E Genetic Mutation Is a Rare But Important Cause of Intermittent Claudication and Chronic Limb-Threatening Ischemia.

BACKGROUND: NT5Egenetic mutations are known to result in calcification of joints and arteries (CALJA), and worldwide, 14 patients from 7 families have been reported.Methods and Results:A total of 5 patients from 2 independent families with CALJA were found in Japan. Of them, 3 complained of intermittent claudication (IC), and 1 suffered from bilateral chronic limb-threatening ischemia (CLTI). Whole-exome sequencing analysis revealed an identical mutation pattern (c.G3C on the exon 1 start codon) that was unique compared withNT5Emutations reported in other countries. CONCLUSIONS: Vascular specialists need to recognize CALJA as a rare cause of ischemic IC and CLTI.

A Case of Chronic Limb-Threatening Ischemia with Heel Ulcers Cured by Revascularization and Partial Calcanectomy.

Ischemic limbs with infected heel ulcers are often difficult to salvage. We present a case of an 82-year-old woman who had bilateral heel ulcers owing to chronic limb-threatening ischemia. She underwent right femoral-terminal posterior tibial artery bypass surgery, but right calcaneus osteomyelitis occurred and inhibited wound healing. She underwent partial calcanectomy (PC), and her right heel healed six months after the bypass surgery. The ulcer on her left foot also healed after distal bypass and PC. We describe our experience with a patient who needed PC to cure her heel ulcers.

Development of gene therapy with a cyclic adenosine monophosphate response element decoy oligodeoxynucleotide to prevent vascular intimal hyperplasia.

OBJECTIVE: Intimal hyperplasia (IH) is the main cause of therapeutic failure after vascular and endovascular surgery. However, there is currently no targeted therapy for the treatment of IH. We recently reported that the inhibition of cyclic adenosine monophosphate response element (CRE) binding protein (CREB) activation is important in vein graft IH. We focused on a decoy oligodeoxynucleotide (ODN) therapeutic strategy for suppressing IH as a clinical application. The objective of this study was to confirm the therapeutic effect of a CRE decoy ODN in an animal model as a novel therapy for preventing intimal hyperplasia as the first step of the preclinical study of our strategy. METHODS: We designed two phosphorothioate CREs and two scramble decoy ODNs and screened them using a CREB transcription assay to check their ability to bind to a CRE sequence. We chose a CRE decoy ODN with high first-binding ability and transfected it into vascular smooth muscle cells (VSMCs) in vitro. Proliferation and migration were assessed using MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assays and modified Boyden chamber assays. We examined CRE activity using a luciferase reporter gene assay. We assessed the expression of messenger RNAs by quantitative real-time polymerase chain reaction. In a wire-injury mouse model (C57BL6, n = 6), CRE decoy ODN was transfected into the injured vessel wall using an ultrasound-sonoporation method in vivo. Mitogen-activated protein kinase-activated protein kinase 3 (MAPKAPK3) and four and a half LIM domains 5 (FHL5) expression of pregrafting vein remnants were assessed by immunohistologic analyses. RESULTS: Compared with scramble decoy ODN, the selected CRE decoy ODN could significantly decrease CRE activity (mean ± standard error of the mean: 0.20 ± 0.03 vs 1.00 ± 0.16, n = 6; P < .05) as shown by a luciferase reporter gene assay, VSMC proliferation (0.73 ± 0.04 vs 0.89 ± 0.02, n = 6; P < .05) and migration (96.4 ± 6.1 vs 311.4 ± 19.1 migrated VSMCs/well, n = 6; P < .05) after 24-hour transfection. The CRE decoy ODN significantly suppressed the formation of IH at injured vessel walls in an animal model, as analyzed by pathologic staining (0.20 ± 0.02 vs 0.56 ± 0.08, area of the intima/area of the artery vs the control after 21 days' transfection, n = 6; P < .05). Furthermore, MAPKAPK3 and FHL5, which are CREB activators, were significantly expressed in pregrafting vein remnants in diabetes mellitus patients. CONCLUSIONS: CREB-CRE signaling is an important mechanism of IH formation, and CRE decoy therapy can help preventing IH. This study is the first part of the preclinical study of our strategy.

[Exposure of Femoral Artery and Vein and Axillary Artery Based on Anatomical Knowledge].

Femoral artery and veins and axillary artery are one of the major vessels in the human body which are easily accessible to circulation. Therefore, these vessels are usually used for cardiac and aortic surgeries to establish extracorporeal circulation through surgical as well as percutaneous technique. Additionally, with increasing a minimally invasive fashion for treatment of cardiac and aortic diseases, these accessible arteries are frequently manipulated, for example transcatheter aortic valve implantation, debranching thoracic endovascular aortic repair and endovascular aneurysm repair. Thus, exposure of the vessels is a basic procedure in this field;cardiac and vascular surgeons need understanding anatomical knowledge of the arteries and the surrounding structures, such as muscles and nerves. Especially, it becomes frequent for surgeons to see a bleeding complication with the increasing endovascular therapy and a calcified and atherosclerotic artery due to peripheral artery disease;these situations increase difficulty of femoral artery exposure. Deep understanding of anatomical knowledge helps to obtain good surgical exposure. We hope that it describes some useful improvements to surgical technique and anatomical understanding of cardiac and vascular surgeons.

Effectiveness and Safety of Ultrasound Guided Lower Extremity Nerve Blockade in Infragenicular Bypass Grafting for High Risk Patients With Chronic Limb Threatening Ischaemia.

OBJECTIVES: Surgical revascularisation to accomplish limb salvage remains preferable in some patients with chronic limb threatening ischaemia (CLTI). The aim of this study was to evaluate the effectiveness and safety of ultrasound guided lower extremity nerve blockade (UGNB) in infragenicular bypass surgery (IGBS). METHODS: This was a single centre, retrospective clinical study. Fifty-nine patients with CLTI (67 limbs) who underwent IGBS under UGNB (femoral and sciatic nerve blockade) at Asahikawa Medical University between January 2012 and December 2017 were compared with patients with CLTI (137 limbs) who underwent IGBS under general anaesthesia (GA) over the same period. Propensity score matching based on pre-operative comorbidities was used to minimise background differences of the two groups. RESULTS: Fifty-six pairs of CLTIs were matched and analysed (55% dialysis dependent). Procedure duration was similar between the two groups, but intraoperative catecholamine index and intravenous fluid volume were lower with UGNB compared with GA (2.9 ± 4.6 vs. 5.9 ± 6.5; p < .01 and 1831 ± 990 vs. 2335 ± 931 mL; p < .01, respectively). The mean arterial blood pressure during induction of anaesthesia was significantly decreased with GA. Post-operatively, the time period to resume a clear liquid and solid food diet was significantly shorter with UGNB (P<0.01 for both outcome measures). Intravenous fluid volume was significanlty lower, while cardiac complications and delirium, based on the NEECHAM confusion scale, occurred significantly less often with UGNB than GA. These significant differences show advantages of UGNB compared to GA. No mortality or major amputations were observed in either group. Early graft thrombosis was observed in five limbs (8.9%) with UGNB and in four limbs with GA (7.1%) (p = .73). CONCLUSIONS: UGNB has advantages for intra- and post-operative management and could be a useful method to prevent peri-operative complications for high risk patients with CLTI. To ensure the effectiveness of UGNB for IGBS for future indications, a randomised study is required.