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The photophysical properties of two isostructural heteroligand lanthanide complexes of general formula Ln(pdtc) 3 (phen) ( pdtc = pyrrolidinedithiocarbamate anion, phen = 1,10-phenanthroline), Ln = Sm 3+ ( 1 ), Eu 3+ ( 2 )) were studied in solid state and dichloromethane (DCM) solution. The two lanthanide complexes were investigated by experimental techniques for structural (single-crystal X-ray diffraction analysis of 1 , powder XRD, TG-DTA) and spectroscopic [electron paramagnetic resonance (EPR), infrared (IR), ultraviolet-visible (UV-vis), photoluminescence (PL)] characterization. DFT/TDDFT/ωB97xD and multireference SA-CASSCF/NEVPT2 calculations with perturbative spin-orbit coupling corrections were applied to construct the Jablonski energy diagrams and to discuss the excited state energy transfer mechanism with competing excited state processes and possible sensitized mechanism of metal-centered emission. The first excited state (S 1 ) involved in the excited state energy transfer L(antenna)-to-Ln was predicted to have interligand ( pdtc -to- phen ) charge transfer character in contrast to the previously predicted ligand-to-metal charge transfer character. The theoretical consideration showed similar relaxation paths and luminescence quenching channels and appropriate Donor*(phen)-Acceptor*(Ln 3+ ) energy gap for 1 and 2 . The experimental measurements in the solid state, however, showed efficient luminescence and good ability to convert UV to visible light only for the Sm(pdtc) 3 (phen) complex. The minor emission of 2 was explained by partial reduction of Eu 3+ , confirmed by EPR and calculated electron density distribution data.

The tetracarbonyl complexes of transition metal chalcogenides M 2 X 2 (CO) 4 , where M = Fe, Co, Ni, Cu and X = S, Se, are examined by density functional theory (DFT). The M 2 X 2 core is cyclic with either planar or non-planar geometry. As a sulfide, it is present in natural enzymes and has a selective redox capacity. The reduced forms of the selenide and sulfide complexes are relevant to the hydrogen evolution reaction (HER) and they provide different positions of hydride ligand binding: (i) at a chalcogenide site, (ii) at a particular cation site and (iii) in a midway position forming equal bonds to both cation sites. The full pathway of water decomposition to molecular hydrogen and oxygen is traced by transition state theory. The iron and cobalt complexes, cobalt selenide, in particular, provide lower energy barriers in HER as compared to the nickel and copper complexes. In the oxygen evolution reaction (OER), cobalt and iron selenide tetracarbonyls provide a low energy barrier via OOH* intermediate. All of the intermediate species possess favorable excitation transitions in the visible light spectrum, as evidenced by TD-DFT calculations and they allow photoactivation. In conclusion, cobalt and iron selenide tetracarbonyl complexes emerge as promising photocatalysts in water splitting.

Excited state energy level diagrams of coumarin-3-carboxylic acid (HCCA) chromophore, Eu(CCA)Cl 2 (H 2 O) 2 (1), Eu(CCA) 2 Cl(H 2 O) 2 (2) , Eu(CCA) 3 (H 2 O) 3 (3), Tb(CCA) 2 Cl(H 2 O) (4) and Tb(CCA) 2 (NO 3 )(H 2 O) (5) in gas phase and polar solution have been calculated by means of DFT/TDDFT/ωB97XD methods. Based on these results, the ability of CCA to sensitize Eu(III) and Tb(III) luminescence has been examined. The competitive excited state processes in the complexes - fluorescence, intersystem crossing (ISC) and phosphorescence, were analyzed depending on the environment, number of the ligands, Ln(III) ion type (Eu and Tb) and counteranion (Cl - and NO 3 - ). It has been found that the environment altered the S 1 state energy, oscillator strength, fluorescence lifetime as well as the S 1 character - polar solution stabilized the S 1 (ππ*) state, whereas non-polar solution (gas phase, solid state) stabilized the S 1 (nπ*) state. The S 1 emission of CCA and favored ISC or direct transfer to the emitting levels of Eu(III). The HCCA triplet (T 1 emission of CCA and favored ISC or direct transfer to the emitting levels of Eu(III). The HCCA triplet (T 1 eV) and (ππ*) character were retained in Eu/Tb-CCA complexes regardless of the environment. The energy gap between the higher energy T ZPE eV) and (ππ*) character were retained in Eu/Tb-CCA complexes regardless of the environment. The energy gap between the higher energy T 1 donor state and the acceptor levels 5 D 1 of Eu(III) (~0.5 eV) and 5 of Tb(III) (~0.1 eV) provided optimal resonance conditions for effective energy transfer for Eu(III), but less probability for Tb(III). The nonradiative energy (CCA → Eu(III)) transfer rates and quantum luminescence yield for 2 and 3 were calculated by a strategy combining DFT geometries, INDO/S excitation energies and calculated Judd-Ofelt parameters. The excitation channel T 4 of Tb(III) (~0.1 eV) provided optimal resonance conditions for effective energy transfer for Eu(III), but less probability for Tb(III). The nonradiative energy (CCA → Eu(III)) transfer rates and quantum luminescence yield for 2 and 3 were calculated by a strategy combining DFT geometries, INDO/S excitation energies and calculated Judd-Ofelt parameters. The excitation channel T 1  →  5 D 0 through an exchange mechanism was predicted as the most probable one to populate the main emissive Eu-centered state in complexes 2 and 3. The more efficient luminescence of 3 than that of 2 was discussed and explained., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Aneurysms of the splenic artery account for about 60% of all aneurysms of visceral arteries. Most of them are asymptomatic until rupture and are discovered accidentally, usually after an imaging study. The treatment is surgical or endovascular depending on the type, location and size. We present a case of a patient with an asymptomatic, accidentally found aneurysm of the splenic artery which we successfully treated with a covered stent. The control CT-angiography on 6th month showed patent stent and totally occluded aneurysm. It is very important in cases of acute abdomen and hemorrhagic shock to think of a ruptured aneurysm. In these cases the treatment of choice is endovascular as it is mini-invasive and organ-saving.

Unlabelled: Carotid endarterectomy (CEA) is a surgical intervention that aims to reduce neurological symptoms in carotid atherosclerosis and prevent brain damage and subsequent neurological deficit., Aim: To study the major risk factors, surgical techniques, applied diagnostic methods and perioperative complications occurring in patients undergoing CEA., Materials and Methods: 496 surgical interventions on the occasion of stenoses and/or occlusions of the carotid arteries were performed for the period 1987-2009 at the department of Vascular Surgery and Angiology of "St. Ekaterina" - University Hospital - Sofia. All patients were operated using standard access under general or local anaesthesia. During surgeries, evaluation of cerebral hemodynamics and function was performed by transcranial Doppler Ultrasound (TCD) and cerebral oximetry (CO). Carotid shunting was selectively applied in cases of deterioration of the values of CO and TCD during cross clamping of the carotid arteries., Results: The highest relative share among cerebrovascular complications took stroke with 2.7% share in the group of asymptomatic patients and 1.7% - in the symptomatic group. Considering the other types of complications with the largest relative share were cardiac complications in both groups of patients - hemodynamic disorders and myocardial infarction., Conclusion: Low values of postoperative mortality and stroke after CEA in our study are comparable with other leading centers, proving that CEA is safe and effective surgical procedure for stroke prevention in both symptomatic and asymptomatic patients. Accurate perioperative diagnostic allows a good approach for choosing the correct surgical strategy.

The success of all vascular interventions depends mainly on the chosen strategy and access, especially in patients with severe co-morbidities, preceding operations or infection. In these cases the combination of retroperitoneal approach and extra-anatomical bypasses makes the revascularization possible. We present a clinical case of a patient after radiotherapy, peritonitis and colostomy with persistent pain in the lower extremities and angiographic finding of bilateral occlusion in the aorto-iliac segment. We did a right retroperitoneal aorto-femoral reconstruction and a crossover femoro-femoral bypass. It is also possible to perform visceral and renal arterial reconstructions with the retroperitoneal approach. In addition, symptomatic and ruptured aneurysms, as well as infected aortic grafts can be operated on with optimal results, without a notable increase in mortality.

Unlabelled: Carotid endarterectomy (CEA) is a surgical intervention that aims to reduce neurological symptoms in carotid atherosclerosis and prevent brain damage and subsequent permanent neurological deficit., Aim: To study the major risk factors, surgical techniques, applied diagnostic methods and perioperative complications occurred in patients undergoing CEA., Materials and Methods: 496 surgical interventions on the occasion of stenosis and/or occlusions of the carotid arteries were performed for the period 1987-2009 at the department of Vascular Surgery and Angiology of "St. Ekaterina"- University Hospital - Sofia. All patients were operated using standard access under general or local anaesthesia. During surgeries, the evaluation of cerebral hemodynamics and function was performed by transcranial Doppler Ultrasound (TCD) and cerebral oximetry (CO). Carotid shunting was selectively applied in cases of deterioration of the values of CO and TCD during cross clamping of the carotid arteries., Results: With the highest relative share among cerebrovascular complications was stroke with 2.7% share in the group of asymptomatic patients and 1.7%--in the symptomatic group. When considering the other types of complications with the largest relative share were cardiac complications in both groups of patients--hemodynamic disorders and myocardial infarction., Conclusion: Low values of postoperative mortality and stroke after CEA in our study are comparable with other leading centers, proving that CEA is safe and effective surgical procedure for stroke prevention in both symptomatic and asymptomatic patients. Accurate perioperative diagnostic allows a good approach for choosing the correct surgical strategy.

Despite the increased volume of patients undergoing selective reconstruction on the occasion of abdominal aortic aneurysms (AAA) in the last decades, the number of patients with rupture of abdominal aortic aneurysms (RAAA) is not significantly decreased. RAAA is catastrophic and life-threatening condition. It remains a challenge to every practitioner. To optimize the surgical practice we studied the literature for the treatment of symptomatic and rupture aneurysm of the abdominal aorta.

Ischemic stroke is the third most common cause of death right after myocardial infarction and malignancies. Most cases of stroke are due to extracranial carotid atherosclerotic disease. The percutaneous transluminal angioplasty and stenting of the carotid arteries have emerged as an alternative to the standart carotid endarterectomy mainly because they are less invasive procedures. Carotid stenting with or without the use of neuroprotection devices proves to be effective in high-risk patients with carotid stenosis. Nevertheless, there is no clear proof that endovascular techniques outmatch the classic surgical methods.

Extracranial carotid artery aneurysms are unusually rare. Their aetiology and clinical picture have significant meaning for their recognition, with the majority involving the common carotid artery--ACC. Approximately one third of these lesions are confined to the ICA, with an equal distribution between the proximal, middle, and distal segments. Nonoperated treatment is associated with a high risk of stroke compare to surgical, wich is think as necessary from most authors, because of the high level of neurologic symptomatic in the studies. Surgical treatment is used for prevention from cerebrovascular deficit.

The first lumbar sympathectomy for treatment of arterial occlusive disease of the lower extremity was performed in 1924 by Julio Diez of Buenos Aires. The standart anatomy textbooks indicate, as a rule that the lumbar sympathetic trunk contains four or five ganglia. The overall anatomic denervation is important for achievement of an adequate sympathectomy of a given segment of an extremity. Criteria and indications for complete sympathetic block are still not clear. Exceptionally important for the improvement of the reology of the lower limbs is the option for a direct increase of the collaterals' debit which could be achieved by extensive profundoplasty. As an addition to the arterial reconstructions, the sympathectomy increases the passability of small vessel anastomosis and the recovery of traumatized arteries. Unilateral or bilateral lumbar sympathectomy is performed by retroperitonal access. From 01.01.2008 till 01.11.2008 in our clinic were performed 117 isolated and after arterial reconstruction lumbar sympathectomies.

The question addressed was whether the use of sympathectomy was of benefit in non-revascularisable critical leg ischaemia. Altogether 387 papers were found, of which 13 represented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses were tabulated. We conclude that lumbar sympathectomy is a minimally invasive procedure with a low complication rate. Randomized controlled trials have failed to identify any objective benefits for lumbar sympathectomy, but subjective improvements in symptoms for patients with highly symptomatic critical leg ischaemia have been consistently demonstrated in multiple cohort studies with sustained symptom improvements in approximately 60% of patients. Lumbar sympathectomy is in process of renaissance and should be considered for symptomatic patients with critical leg ischaemia as an alternative to amputation in patients with otherwise viable limbs.

Unlabelled: Noneoperative treatment of the internal carotid artery (ICA) occlusion is associated with increased recurrent stroke rates. Several randomized trials have validated the use of carotid endarterectomy (CEA) to treat symptomatic internal carotid artery occlusions. The aim of this study is to analyze the data from external CEA for treatment of symptomatic ICA occlusions, to evaluate its safety and outcomes., Material and Methods: 302 surgical interventions on the carotid artery in 295 patients had been operated for 42 months (from January 2006 to June 2009) at the "Department of Vascular Surgery and Angiology" of "St. Ekaterina" University Hospital --Sofia. 30 patients were with symptomatic ICA occlusion, and in 17 of them we used external carotid endarterectomy. The patients had been analyzed according to the type of surgical intervention and clinical picture. The frequency of postoperative complications and outcomes had been investigated., Results: There were no complications in the early postoperative period. We found reduction or disappearing of the neurological signs in the patients. On the 30th day after the surgery patients were without any clinical symptoms. There were no restenosis or reoclusions at the postoperative check up. No patients died in the perioperative period (30 days)., Conclusion: The restoration of the ICA blood flow reduce the risk of recurrent strokes, which is demonstrated in the long term follow up. External carotid endarterectomy (ECA) is estimate procedure for relieving the hemispheric symptoms in patients with ICA occlusions.

Aim: The aim of this study was to evaluate the prevalence of and risk factors for chronic venous disease (CVD) in the Bulgarian adult population seeking medical help from general practitioners., Methods: The design was a cross-sectional descriptive survey. Each general practitioner (GP) enrolled 50 consecutive patients aged 18 and over attending for a routine consultation. A subsample of these patients was reappraised by a group of specialists to confirm the GPs diagnosis., Results: A total of 576 GPs selected 26 785 subjects to participate in the survey. In the GP survey, 11 724 subjects (44%) were found to be suffering from CVD. Specialist reappraisal of a subset of 373 subjects confirmed the initial diagnosis in 91.2% of cases. CVD was more prevalent in females (51%) than in males (32%) (P<0.0001) and prevalence increased with age and body mass index., Conclusions: Heavy legs, pain in the legs, and a sensation of swelling were the most frequently reported symptoms. Varicose veins and telangiectasias were the most common signs in both males and females, but with a higher frequency of varicose veins in males and telangiectasias in females. Increasing age, pregnancy, and a positive family history were found to be risk factors for CVD.

Hyperperfusion syndrome is a complication with frequency about 3 per cent and unclear etiological factors who mostly lead to hard neurological deficit and/or death for the patient. Symptoms are headaches, fits, confusion, focal neurological sings to intracerebral hemorrhage. The prevention and control are accomplished by active monitoring of intracranial blood flow and systolic blood pressure. Hyperperfusion syndrome can be clinicaly performed with or without hemorrhage. We present a case of hyperperfusion syndrome after carotid endarterectomy of 59-years-old man operated at the Department of Vascular surgery and Angiology of "St. Ekaterina" hospital. The patient had thrombosis of one carotid artery and stenosis of the other and two old cerebral infarctions. In the early postoperative period the patient developed a clinical picture of awake coma with quadriparesis and right plegia. On the 14-th day after the surgical intervention the patient left the clinic in better condition and was directed to his neurologist for observation.

In patients with chronic limb ischemia (CLI) the atherosclerotic process involves the aorto-iliac and/or the femoro-popliteal segment. In most cases there are steno-occlusive lesions of the superficial femoral artery but the profunda femoris artery is often spared. In 30% of the diabetic patients and in 9% of the nondiabetic there are lesions of the profunda femoris artery which are mainly ostial or can be found at the most proximal part. The revascularization of the profunda femoris artery is an important operative method especially in many cases where there is no other possibility of vascular reconstructive operation. In this paper we discuss different diagnostic tests and criteria, which we used when deciding which patients are suitable for profundoplasty--segmental pressures, angiography, Doppler triplex scan.

We present a case of a 56-year-old male patient who was admitted at the clinic with complains of pain and blue-colored index finger of the left hand since a couple of days. He has an anamnesis of claudication of the left arm. After the contrast CT-angiogram, which showed a 80% stenosis of the left subclavian artery, the patient had an allergic reaction. This changed our initial plan for an endovascular intervention and we proceeded to an open surgical procedure. Because of the suitable anatomical characteristics we did a replantation of the subclavian artery to the common carotid artery. The postoperative period went smoothly. Six months after the intervention the patient is feeling fine. He has pulse on the radial and ulnar arteries and no sign of the necrosis of the index linger. Subclavian-carotid transposition is a safe method for the treatment of steno-occlusive lesions of the subclavian artery. Except the ortograde physiological blood flow through the vertebral artery and the construction of only one anastomosis, the main advantage over the bypass surgery is not using autogenous or heterogenous prosthetic material.

For surgical treatment of aorto-iliac occlusive diseases the prosthetic grafts are used for aorto-femoral bypass in which the end to side anastomoses are done on anterior aspect of aorta. But this approach is leading to some disadvantages caused by gravity or pressure imposed by abdominal viscera and resulting to kinking to the anastomotic area between the vertebral column and viscera which brings about turbulence, platelet aggregation, thrombus formation, and its organization which finally occludes the lumen. Nazem's method of lateral end-to-side anastomosis preferably to the left side of aorta will be without the mentioned bad on sequences, thereby greatly reducing mortality and morbidity. We recommend the interested academic groups use our method, which follows and we welcome them sharing their results with us.

The merits of the Russian physician Ugryumov, participant in the Liberation Russian-Turkish war (1877-78) and pioneer in the organization of health services in Eastern Rumelia are emphasized. Ugryumov made part of the IV brigade of the Bulgarian volunteer corps as a physician; he organized a hospital for typhus patients in Plovdiv, which subsequently was converted into the First State Hospital. Dr. Ugryumov organized the first educational course for surgeon's assistants in Bulgaria.