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Background: Microplastics and nanoplastics (MNPs) are emerging as a potential risk factor for cardiovascular disease in preclinical studies. Direct evidence that this risk extends to humans is lacking., Methods: We conducted a prospective, multicenter, observational study involving patients who were undergoing carotid endarterectomy for asymptomatic carotid artery disease. The excised carotid plaque specimens were analyzed for the presence of MNPs with the use of pyrolysis-gas chromatography-mass spectrometry, stable isotope analysis, and electron microscopy. Inflammatory biomarkers were assessed with enzyme-linked immunosorbent assay and immunohistochemical assay. The primary end point was a composite of myocardial infarction, stroke, or death from any cause among patients who had evidence of MNPs in plaque as compared with patients with plaque that showed no evidence of MNPs., Results: A total of 304 patients were enrolled in the study, and 257 completed a mean (±SD) follow-up of 33.7±6.9 months. Polyethylene was detected in carotid artery plaque of 150 patients (58.4%), with a mean level of 21.7±24.5 μg per milligram of plaque; 31 patients (12.1%) also had measurable amounts of polyvinyl chloride, with a mean level of 5.2±2.4 μg per milligram of plaque. Electron microscopy revealed visible, jagged-edged foreign particles among plaque macrophages and scattered in the external debris. Radiographic examination showed that some of these particles included chlorine. Patients in whom MNPs were detected within the atheroma were at higher risk for a primary end-point event than those in whom these substances were not detected (hazard ratio, 4.53; 95% confidence interval, 2.00 to 10.27; P<0.001)., Conclusions: In this study, patients with carotid artery plaque in which MNPs were detected had a higher risk of a composite of myocardial infarction, stroke, or death from any cause at 34 months of follow-up than those in whom MNPs were not detected. (Funded by Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale and others; ClinicalTrials.gov number, NCT05900947.)., (Copyright © 2024 Massachusetts Medical Society.)

Primary aortic occlusion (PAO) is defined as acute occlusion in the absence of aortic atherosclerosis or aneurysm. PAO is a rare disease with acute onset and can determine massive parenchymal ischemia and distal arterial embolization. The aim of our study was to focus on the assessment of clinical characteristic, CT signs, medical and surgical treatment, complication rates and the overall survival of PAO., Materials and Methods: We retrospectively analyzed the data of all patients with acute lower limb ischemia and a final surgical or discharge diagnosis of PAO who underwent aortic CT angiography in ER settings in our hospital from January 2019 to November 2022., Results: A total of 11 patients (8 males/3 females; male/female ratio, 2.66:1, age range 49 to 79 years-old, mean age 65.27 y/o) with acute onset of lower limb impotence or ischemia were diagnosed with PAO. The etiology was thrombosis in all patients. The aortic occlusion was always located in the abdominal aorta and extended bilaterally through the common iliac arteries. The upper limit of the thrombosis was detected in the aortic subrenal tract in 81.8% of the cases, and in the infrarenal tract in 18.2%. A total of 81.8% of the patients were referred to the ER for symptoms related to lower limb: bilateral acute pain, hypothermia and sudden onset of functional impotence. Two patients (18.2%) died before undergoing surgery for multi-organ failure determined by the severe acute ischemia. The other patients (81.8%) underwent surgical treatment that included aortoiliac embolectomy (54.5%), aortoiliac embolectomy + aorto-femoral bypass (18.2%) and aortoiliac embolectomy and right lower limb amputation (9.1%). The overall mortality was 36.4% while the estimated survival at 1 year was 63.6%., Conclusions: PAO is a rare entity with high morbidity and mortality rates if not recognized and treated promptly. Acute onset of lower limb impotence is the most common clinical presentation of PAO. Aortic CT angiography is the first-choice imaging technique for the early diagnosis of this disease and for the surgical treatment, planning and assessment of any complications. Combined with surgical treatment, anticoagulation is considered the first-line medical therapy at the time of diagnosis, during surgical treatment and after at discharge.

Gliomas are the most common brain tumours with a poor prognosis due to their aggressiveness and propensity for recurrence. The 18 kDa translocator protein (TSPO) has been demonstrated to be greatly expressed in glioma cells and its over-expression has been correlated with glioma malignance grades. Due to both its high density in tumours and the pro-apoptotic activity of its ligands, TSPO has been suggested as a promising target in gliomas. With the aim to evidence if the TSPO expression level alters glioma cell susceptibility to undergo to cell death, we analysed the effects of the specific TSPO ligand, PK 11195, in human astrocytoma wild-type and TSPO-silenced cell lines. As first step, TSPO was characterised in human astrocytoma cell line (ADF). Our data demonstrated the presence of a single class of TSPO binding sites highly expressed in mitochondria. PK 11195 cell treatment activated an autophagic pathway followed by apoptosis mediated by the modulation of the mitochondrial permeability transition. In TSPO-silenced cells, produced by siRNA technique, a reduced cell proliferation rate and a decreased cell susceptibility to the PK 11195-induced anti-proliferative effect and mitochondrial potential dissipation were demonstrated respect to control cells. In conclusion, for the first time, PK 11195 was demonstrated to differentially affect glioma cell survival in relation to TSPO expression levels. These results encourage the development of specific-cell strategies for the treatment of gliomas, in which TSPO is highly expressed respect to normal cells., ((c) 2008 Wiley-Liss, Inc.)

Gliomas are one of the most malignant cancers. The molecular bases regulating the onset of such tumors are still poorly understood. The translocator protein (TSPO), formerly known as the peripheral-type benzodiazepine receptor, is a mitochondrial permeability transition (MPT)-pore protein robustly expressed in gliomas and involved in the regulation of apoptosis and cell proliferation. TSPO expression levels have been correlated with tumor malignancy. Here we describe the production of C6 rat glioma cells engineered to over-express the TSPO protein with the aim of providing the first direct evidence of a correlation between TSPO expression level and glioma cell aggressiveness. We observed that TSPO potentiates proliferation, motility and transmigration capabilities as well as the ability to overcome contact-induced cell growth inhibition of glioma cells. On the whole, these data demonstrate that TSPO density influences metastatic potential of glioma cells. Since several data suggest that TSPO ligands may act as chemotherapeutic agents, in this paper we also demonstrate that TSPO ligand-induced cell death is dependent on TSPO density. These findings suggest that the use of TSPO ligands as chemotherapeutic agents could be effective on aggressive tumor cells with a high TSPO expression level.

A series of 5'-carbamoyl and 5'-thionocarbamoyl derivatives of 2'-C-methyl analogues of the A(1) adenosine receptor (A(1)AR) full agonists N(6)-cyclopentyladenosine (CPA), 2-chloro-N(6)-cyclopentyladenosine (CCPA), N(6)-[3-(R)-tetrahydrofuranyl]adenosine (tecadenoson), and 2-chloro analogue (2-Cl-tecadenoson) was synthesized and evaluated for their affinity for adenosine receptor subtypes from bovine, porcine, and human species. In the N(6)-cyclopentylamino series, the 5'-substituted derivatives showed a reduced affinity at the bovine A(1)AR compared to the parent compounds; however, the selectivity for A(1) versus A(2A) receptor was retained or increased. The corresponding N(6)-3-(R)-tetrahydrofuranylamino analogues displayed a very low affinity toward the bovine A(1)AR. The 5'-methylthionocarbamoyl derivative of 2'-Me-CCPA showed the best affinity at porcine A(1)AR with a K(i) value of 13 nM. At human AR subtypes tecadenoson derivatives showed 2.3- to 5-fold lower affinity at A(1)AR and very low affinity at the other subtypes (A(2A), A(2B), and A(3)) compared to the corresponding N(6)-cyclopentyl analogues. The 5'-carbamoyl and 5'-thionocarbamoyl derivatives of 2'-Me-CCPA 3, 4, 7 and tecadenoson derivative 12 were found to be partial A(1) agonists at the porcine receptor. Docking studies explained the lower affinity of N(6)-3-(R)-tetrahydrofuranyl-substituted compounds at bovine A(1)AR compared to that of N(6)-cyclopentyl analogues, showing that the oxygen of the tetrahydrofuranyl ring establishes unfavorable electrostatic interactions with the CO oxygen of Asn254. The low binding affinity of the 2'-C-methyl-N(6)-3-(R)-tetrahydrofuranyl adenosine analogues at human A(1)AR may be ascribed to the presence of unfavorable interactions between the hydrophilic tetrahydrofuranyl ring and the surrounding hydrophobic residues Leu250 (TM6) and Ile274 (TM7).

Fluorescent ligands for the peripheral-type benzodiazepine receptor (PBR) featuring the 7-nitrobenz-2-oxa-1,3-diazol-4-yl moiety were synthesized, based on N,N-dialkyl-2-phenylindol-3-ylglyoxylamides, a potent, selective class of PBR ligands previously described by us. All the new ligands are moderately to highly potent at the PBR, with a complete selectivity over the central benzodiazepine receptor. Results from fluorescence microscopy showed that these probes specifically labeled the PBR at the mitochondrial level in C6 glioma cells.

Peripheral benzodiazepine receptor (PBR) has been considered a promising drug target for cancer therapy, and several ligands have been developed for this purpose. Human T-lymphoma Jurkat cells have been considered as lacking PBR and are often used as negative control to prove the specificity of PBR ligands effects. It is surprising that we evidenced PBR protein expression in this cell line by means of Western blotting and immunocytochemistry assays using specific anti-PBR antibodies. PBR intracellular localization was evidenced in mitochondria and nuclei, as demonstrated by confocal and electron microscopy. The binding of the [(3)H]4'-chloro derivative of diazepam [(3)H]7-chloro-5-(4-chlorophenyl)-1,3-dihydro-1-methyl-2H-1,4-benzodiazepin-2-one (Ro5-4864) and the isoquinoline carboxamide derivative [(3)H]1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3 isoquinolinecarboxamide (PK11195) evidenced a single class of binding sites with an unusual affinity constant (K(d)) of 1.77 +/- 0.30 and 2.20 +/- 0.20 microM, respectively. The pharmacological profile of the classic ligands showed that PK11195 was the most potent inhibitor in the radioligand binding assays followed by Ro5-4864 and diazepam, whereas clonazepam, a specific ligand for the central-type receptor, showed a K(i) >1.0 x 10(-4) M. By a combined strategy of reverse transcriptase-polymerase chain reaction and Southern blot experiments, we succeeded in isolating and cloning the full-length Jurkat PBR cDNA, called JuPBR. The JuPBR gene showed two single-nucleotide polymorphisms resulting in the two substitutions, Ala147 --> threonine and His162 --> arginine, of PBR amino acidic sequence. In conclusion, for the first time, we demonstrated PBR expression in Jurkat cells: the protein bound classic PBR ligands with micromolar affinity constants and presented a modified amino acidic sequence consequent to the detection of two gene polymorphisms.

The present paper reports the synthesis and binding studies of new 2-phenylpyrazolo[1,5-a]pyrimidin-3-yl acetamides as selective Peripheral Benzodiazepine Receptor (PBR) ligands. The variability of substituents at the 3-position was investigated and a 3D-QSAR model was proposed to evaluate the effect of different substitutions on the acetamide moiety. In addition, a subset of the novel compounds showing high affinity for PBR was tested for their ability to modulate the steroid biosynthesis in C6 glioma cells.

Mitochondrial benzodiazepine-receptor (mBzR) ligands constitute a heterogeneous class of compounds that show a pleiotropic spectrum of effects within the cells, including the modulation of apoptosis. In this paper, a novel synthetic 2-phenylindol-3-ylglyoxylamide derivative, N,N-di-n-butyl-5-chloro-2-(4-chlorophenyl)indol-3-ylglyoxylamide (PIGA), which shows high affinity and selectivity for the mBzR, is demonstrated to induce apoptosis in rat C6 glioma cells. PIGA was able to dissipate mitochondrial transmembrane potential (DeltaPsim) and to cause a significant cytosolic accumulation of cytochrome c. Moreover, typical features of apoptotic cell death, such as caspase-3 activation and DNA fragmentation, were also detected in PIGA-treated cells. Our data expand the knowledge on mBzR ligand-mediated apoptosis and suggest PIGA as a novel proapoptotic compound with therapeutic potential against glial tumours, in which apoptosis resistance has been reported to be involved in carcinogenesis.

Purpose: To describe a unique case of misdiagnosed leiomyosarcoma of the common femoral artery presenting with signs and symptoms of high-grade stenosis, which was treated with stent placement., Case Report: A 31-year-old woman with a history of diabetes and hyperlipidemia had recurrent claudication and showed significant in-stent restenosis of the common femoral artery in a postoperative angiogram at 5 months. The patient's clinical stage remained unchanged after repeat percutaneous intervention, and leiomyosarcoma was diagnosed from surgical specimens. The patient underwent resection and repair of the involved artery. She has survived 30 months with no further evidence of local recurrence or systemic metastatic disease., Conclusions: Endovascular repair may cause a long delay in the diagnosis of an arterial leiomyosarcoma mimicking peripheral occlusive disease.

Background: Treatment of lymphoceles complicating vascular procedures is controversial. The purpose of this study was to evaluate the practicability, effectiveness and safety of conservative management on an outpatient basis., Methods: Medical records were reviewed for 23 postoperative lymphoceles (in 18 patients) seen at our institution between 1986 and 1999. Diagnosis was made by physical examination and needle aspiration of fluid collection; bacterial cultures were obtained in all. Ultrasonography was performed in all patients, lymphoscintigraphy (99mTc HSA) in 11, angio-TC in 2 cases, MRI in 3 large lymphoceles., Results: Twenty-one lymphoceles developed in the groin, 2 in the thigh and were mostly (72.2%) diagnosed after hospital discharge. Imaging techniques detected subcutaneous wound collection; in addition, lymphoscintigraphy showed lymphatic interruption and collateral pathways in patients with limb swelling. Outpatient management consisted of limited ambulation, limb elevation and pressure dressings; no serial aspirations were made. Resolution was obtained in all patients over a mean period of 21 days (range, 12 to 35). No patient required re-hospitalization or developed wound and/or graft infection. No recurrence was noted after a follow-up of all patients for 1 year., Conclusions: Outpatient treatment of lymphoceles following arterial reconstructive procedures can be performed safely. Significant advantages of this pathway include no re-hospitalization and cost reduction.

The goal of cerebral protection in carotid surgery is to reduce postoperative central neurological complications and thus reduce morbidity-mortality of carotid endarterectomy. With improving understanding of the mechanism leading to neurological complications, means of achieving cerebral protection have been developed. Preoperative evaluation of the ischemic risk is based on the neurological examination and on computed tomography and magnetic resonance imaging findings. The possibilities of arterial supply during carotid cross-clamping can be recognized with the help of arteriography, transcranial Doppler or angio-MRI. Selective or systematic use of an intraluminal shunt and preoperative heparin therapy are the main methods used for cerebral protection. The risk of early postoperative stroke can also be reduced by careful preoperative anatomic control to detect any technical failure. Discussion on the usefulness of monitoring cerebral function during the procedure is closely related to the experience of the surgical team. The only method currently accepted by all surgeons is the use of stents during carotid angioplasty to achieve cerebral protection.

Background: To evaluate the feasibility and safety of surgical treatment of the superficial temporal artery aneurysms on an outpatient basis., Methods: The records of 5 patients seen at our institution from 1983 to 1997 were reviewed retrospectively. Preoperative diagnosis was made by patient s history and physical examination, with no further evaluation., Results: Outpatient ligation and excision of four aneurysms of distal branches of the superficial temporal artery (3 frontal, 1 parietal) and one involving its proximal portion was performed under local anesthesia. Supplementation with minimal intravenous sedation facilitated the treatment in an uncooperative child and in the patient affected with proximal STA aneurysm. All procedures were uneventful. Patients were discharged a few hours after surgical treatment. No patient required hospitalization following discharge. No recurrence was noted during follow-up periods of 2 to 16 years., Conclusions: Outpatient diagnosis and excision of aneurysm of the superficial temporal artery can be performed safely. Significant advantages of this pathway include no hospital admission and cost reduction.