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HSnBr and DSnBr have been detected for the first time by a combination of laser-induced fluorescence (LIF), fluorescence hole-burning, and wavelength resolved emission spectroscopies. The transient molecules were produced in a twin-discharge jet using separate precursor streams of SnH 4 /SnD 4 and HBr/DBr, both diluted in high pressure argon. The à 1 A″-X̃ 1 A' spectrum of HSnBr only consists of the 0 0 0 and 2 0 1 cold bands that show clearly resolved subband structure with fluorescence lifetimes varying from 526 to 162 ns. The DSnBr LIF spectrum exhibits four bands (0 0 0 , 2 0 1 , 2 0 2 , and 1 0 1 ) whose fluorescence lifetimes decrease from 525 ns (0 0 ) to 175 ns (1 1 ). Single vibronic level emission spectra have provided extensive information on the ground state vibrations, including all the anharmonicities and the harmonic frequencies. Fluorescence hole-burning experiments have shown that a few higher HSnBr nonfluorescent levels are very short-lived but still detectable. The ab initio studies of Tarroni and Clouthier [J. Chem. Phys. 156, 064304 (2022)] show that these molecules dissociate into SnBr + H on the excited state potential surface and this is the cause of the short fluorescence lifetimes and breaking off of the LIF spectra. HSnBr is a barely fluorescent molecule in the sense that only vibrational levels less than or equal to 317 cm -1 in the excited state emit detectable photons down to the ground state.

Transmittance and absorbance data in the form of a spectral atlas have been obtained from Fourier transform spectra recorded on a commercial (Bomem DA3) instrument, operated with an external white light source injected through the instrument's `emission' port. The sample was a sealed, evacuated cell containing a small quantity of 130 Te. This cell was placed in a ceramic furnace maintained close to 620 °C, with tellurium vapor pressures 8-11 Torr. The data are intended as an aid to spectral calibration in the blue-green to violet region. The data relate to work published in J. Mol. Spectrosc. 384 111,589 (2022)., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests. Although there is no obvious competing interest, we indicate that Joseph M. Cardon is an employee of Ideal Vacuum Products, a company that commercializes the tellurium reference cell and temperature-controlled furnace cited in the paper., (© 2022 The Authors.)

Redox-active sites present at large concentrations as part of a solid support or dissolved as molecules in fluid solutions undergo reversible self-exchange electron-transfer reactions. These processes can be monitored using a variety of techniques. Chronoamperometry and cyclic voltammetry are common techniques used to interrogate this behavior for molecules bound to mesoporous thin films of wide-bandgap semiconductors and insulators. In order to use these techniques to obtain accurate values for apparent diffusion coefficients, which are proxies for rate constants for self-exchange electron transfer, it is imperative to take into consideration nonidealities in redox titrations, parasitic currents, and ohmic resistances. Using spectroelectrochemical measurements taken concurrently with measurements of chronoamperometry data, we show that the spectroscopic data is not confounded from effects of parasitic currents or electroinactive dyes. However, we show that the thickness of the thin film over the region that is optically probed by the measurements must be known. When each of these considerations is included in data analyses, calculated apparent diffusion coefficients are, within error, independent of the method used to obtain the data. These considerations help reconcile variations in apparent diffusion coefficients measured using different techniques that have been reported over the past several decades and allow correct analyses to be performed in the future, independent of the method used to obtain the data.

Total synthesis of the anticancer peptide natural product yaku'amide A is reported. Its β-tert-hydroxy amino acids were prepared by regioselective aminohydroxylation involving a chiral mesyloxycarbamate reagent. Stereospecific construction of the E- and Z-ΔIle residues was accomplished through a one-pot reaction featuring anti dehydration, azide reduction, and O→N acyl transfer. Alkene isomerization was negligible during this process. These methods enabled a highly convergent and efficient synthetic route to the natural product., (© 2020 Wiley-VCH GmbH.)

Attempts to perform the OsO 4 -catalyzed enantioselective base-free aminohydroxylation of β,β-disubstituted enoates are described. Low yields and racemic products were obtained in the presence of standard chiral ligands, suggesting the occurrence of a "Second Cycle" process due to slow hydrolysis of the amino alcohol product from the Os metal center. Support for this hypothesis was provided by the slightly improved enantioselectivity (60:40 er) obtained with an amino alcohol ligand. Based on density functional theory calculations, it is proposed that the lack of significant enantioselectivity is due to a low-energy (3 + 2) oxo/imido cycloaddition transition state without the chiral ligand in the Second Cycle that outcompetes protonolysis in the First Cycle.

Objective: The aim was to assess 18 month outcomes of the paclitaxel eluting balloon (PEB) in patients with femoropopliteal (FP) in-stent restenosis (ISR)., Methods: In a national prospective and multicentre cohort study, symptomatic patients with femoropopliteal in-stent restenosis were included from January 2012 to June 2013. Patients were treated by paclitaxel eluting balloon angioplasty (In Pact Admiral, Medtronic, Santa Rosa, CA, USA). Clinical and duplex scan follow-up evaluations were performed at 1, 3, 6, 9, 12, and 18 months. The primary endpoint was freedom from target lesion revascularisation (TLR) at 12 months. Secondary endpoints were major adverse cardiovascular events (MACE), Target extremity revascularisation (TER), primary and secondary sustained clinical improvement, recurrent restenosis rate, primary and secondary patency, quality of life assessed by EQ-5D questionnaire, technical success, clinical success, and length of stay RESULTS: A total of 53 patients were enrolled. After a blinded review, 10 patients were defined as protocol violation because restenosis occurred more than 2 years after stent implantation. Procedures were performed in 55 limbs, 48 (87%) for claudication and 7 (13%) for critical limb ischaemia. The mean diameter and length of PEB were 6 ± 0.57 mm and 86 mm ± 32 mm, follow-up was 17 months (range 1-19). At 1 year, the survival rate was 96 ± 2.7% and freedom from TLR and TER were 90.2 ± 4.2% and 85 ± 5%, respectively. Sustained primary and secondary clinical improvements were 78.6 ± 5.7% and 92.0 ± 3.8%, respectively. At 1 year, the primary patency rate was 83.7 ± 5.0%. Prior to the procedure, the mean EQ-5D score was 66 ± 14 and 74 ± 16 at 1 year (p = .10). Two patients died during follow-up; one patient died 33 days after the procedure because of limb ischaemia., Conclusion: PEB for the treatment of FP ISR is associated with a low rate of re-interventions and restenosis. Clinical improvement is maintained at 18 months., (Copyright © 2016 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.)

A concise synthesis of peptides that contain E- or Z-dehydroisoleucine (ΔIle) residues is reported. The key reaction is an unusual anti dehydration of β-tert-hydroxy amino acid derivatives that is mediated by the Martin sulfurane. A subsequent tandem Staudinger reduction-O → N acyl transfer process forges an amide bond to the ΔIle residue with minimal E/Z alkene isomerization. Density functional calculations attribute the stereospecific dehydration to a highly asynchronous E2 anti process.

Objective: To evaluate mid-term primary patency of the femoral artery stenting in correlation with usCRP level and characteristics of the population, morphological aspect of the lesions and interventional techniques., Methods: Patients were prospectively included in a multicenter study (18 centers in France) after stenting (SMART, Cordis Johnson & Johnson, Issy-les-Moulineaux, France) of the superficial femoral artery (SFA). Inclusion and exclusion criteria were based on recommendations and every day practice of the centers., Results: Thus 255 patients (183 men; mean age: 69 years; range 44-92) were included. Technical success of the SFA stenting was 100% without any complications and primary angiographic success 97%. usCRP level increased significantly (p < 0.05) between before and 24h after SFA stenting. In the subgroup of patients without initial inflammation (n = 157), usCRP increased significantly (p < 0.05) in the group of patient with initial thrombosis and additional intervention (graft, amputation, angioplasty on other arterial bed) in the same procedure compared to the remaining patients. Restenosis rate was 12.4% (26/209 patients) at 7 ± 2 months. Before stenting, usCRP level was not predictive of a restenosis, whereas after stenting, an increase of the 24h usCRP level was significantly higher in the subgroup of patient with an occlusion at mid-term (8 patients; p < 0.05)., Conclusion: This study demonstrated good patency at 7 months of SFA stenting with nitinol SMART with an increase of the usCRP level 24h after stenting in favour of the presence of an occlusion at mid-term follow-up., (Copyright © 2010 Elsevier Masson SAS. All rights reserved.)

Popliteal-to-distal bypass is still the gold standard for limb salvage. However, some patients, especially elderly or diabetic patients, are not eligible for such treatment; and problems may arise, including poor healing of distal surgical wounds, delayed resumption of ambulation, and prolonged hospitalization. This prospective multicenter study carried out on an intent-to-treat basis includes 53 extremities in 48 patients presenting critical ischemia due to infrageniculate arterial lesions with no proximal lesions. Two populations were isolated: diabetic patients (56.6%) and elderly patients over 80 years (45%). In 82% of cases the arterial lesions were long, i.e., more than 1 cm. The limb salvage rate at 1 year was 81%. Postoperative mortality was 9%, and mortality at 1 year was 22.6%. These results show that cutting balloon angioplasty can be proposed as primary treatment in patients with critical ischemia due to popliteal and distal artery lesions.

We report the case of a 58-year-old man with erysipelas of both buttocks secondary to lymphoedema after pelvis surgery for prostatic cancer and multiple vascular interventions for iliofemoral thrombosis. The diagnosis was based on clinical examination and lymphoscintigraphy. This location of lymphoedema, limited to the buttocks, is uncommon; lower limbs are usually affected. This location needs a specific curative and preventive treatment, including antibiotic therapy, lymphatic drainage and contention to abate the condition and prevent a relapse.

Incompetence of the deep venous valve is a common feature of post-thrombotic deep venous insufficiency. Various surgical techniques have been proposed to treat reflux. In this study we describe long-term results of a novel transposition technique using the ipsilateral greater saphenous vein. From 1984 to 1994 we used this procedure to treat 16 patients including 10 men and 6 women with a mean age of 56 years (range: 25 to 76 years). In all 16 cases the indication for surgery was incapacitating pain associated with recurring ulceration in 9 patients. From the results of using this technique we conclude that transposition using the ipsilateral greater saphenous vein is safe and effective with good mid-term results, especially for pain. For ulcers the primary success rate was 55% but this increased to 84% with proper surveillance and treatment of secondary insufficiency of the superficial venous system.

Purpose: To report the results of a multicenter safety trial of percutaneous carotid stenting performed by vascular surgeons., Methods: Symptomatic or asymptomatic patients > or = 65 years of age with internal carotid artery (ICA) stenoses > or = 70% and < or = 2-cm long were eligible for enrollment. The procedures were performed in an operating room with the choice of anesthesia and the percutaneous access site at the discretion of the surgeon. Only Palmaz stents were used., Results: From January 1, 1996 to December 31, 1997, 99 patients (74 men, mean age 70 years, range 51 to 94) were enrolled in the study. More than half (57 of 99 patients) were asymptomatic. The direct cervical approach was used predominantly (97%). Three (3%) cases were converted to surgery for inability to access the artery or deploy the stent (technical success 97%). No perioperative death or myocardial infarction was reported. Six (6%) procedural complications included 1 reversible arterial spasm, 2 dissections, 1 cervical hematoma, and 2 residual stenoses. One neurological event reversed within 7 days (1% minor stroke rate) and 4 (4%) transient ischemic attacks resolved within 24 hours. One (1%) asymptomatic early occlusion occurred 2 days postoperatively. No neurological event was observed in the 1- to 24-month follow-up (mean 13 months). Two (2%) patients died of nonprocedurally related causes. No stent compression was seen, but 1 asymptomatic occlusion and 3 asymptomatic, non-flow-limiting restenoses (2 < 40%, 1 at 60%) were found within 1 year (3% restenosis rate on an intention-to-treat basis). Patency was 98% at 1 year., Conclusions: The results of this trial support the contention that carotid stenting of short ICA lesions can be performed with a low neurological complication rate.

Due to their position deep in the pelvis, the classical surgical treatment of iliac artery aneurysm leads to a high morbidity and mortality rate. The transfemoral percutaneous repair of these aneurysms is now possible thanks to a new device the endoprosystem I from "Mintech". We began in 1994 a study including radiological, cardiac and vascular centers all of them skilled in endovascular procedures. 27 patients entered the study: 1 patient died, 2 attempt failed and 2 presented leakage: the immediate failure rate was then 18.5%. For the late result (min 6, Max 19, mean 12 months) we had 1 thrombosis treated by surgery, 1 restenosis treated by PTA. We did not see any polyester dilatation or reactivation of aneurysm at the scan control at one year. We conclude that the percutaneous treatment of iliac aneurysm is possible and safe but we need long term result to validate the method.

The purpose of this study was to evaluate the feasibility of transluminal techniques in an unselected group of patients and to assess long-term outcome in successful procedures. All patients in whom iliac artery recanalization was attempted were included in this study. Patients with an occluded prosthesis or recent embolism were excluded. A total of 37 patients were studied. Assessment of the success or failure of the procedure was based on the results of control arteriography. Recanalization was deemed successful in 31 patients. This study demonstrates that transluminal recanalization of occluded iliac arteries by a surgeon is indeed feasible. Primary patency was 66% at 24 months. The potential risk, however, is long-term restenosis. Thus follow-up examination every 6 months is recommended including pressure index measurements after exercise and color Doppler ultrasonography of the recanalized zone.

A total of 85 occluded superficial femoral arteries were treated using the rotational transluminal angioplasty catheter system (ROTACS). The mean length of the occlusions was 7cm; 76% were uncalcified or only slightly calcified whereas 24% were calcified or highly calcified. The mean preoperative ankle:brachial index was 0.51. Primary success was achieved in 62 of 85 cases (73%). The mean length of reperfused occlusions was 6.2 cm: 26% of these lesions were calcified. The mean ankle:brachial index was 0.91. There were 23 primary failures (27%): reperfusion was impossible in 11 cases (including one complicated by perforation) and there were eight dissections, three cases where residual stenosis exceeded 50%, and one other unspecified failure. The mean length of these occlusions was 10.5 cm; 17% were calcified. Two patients developed a distal embolus and one died 10 days after reperfusion. The probability of primary patency of a reperfused artery was 44% at 1 year. Forty-two of the 62 patients who achieved primary success remained symptom free; the mean length of the original occlusion was 4.5 cm. Fifteen patients developed a new area of stenosis whereas five others exhibited new occlusion after a mean interval of 6 months. The mean length of these reperfused arteries was 9 cm. The probability of secondary patency at 1 year was 58%. Arterial calcification did not appear to influence the feasibility of reperfusion using the catheter. The main factor determining successful reperfusion was the length of the occlusal defect (P < 0.05). Reperfusion using the ROTACS did not improve the feasibility of reperfusion by conventional transluminal angioplasty.(ABSTRACT TRUNCATED AT 250 WORDS)

The study was carried out on patients with intermittent claudication (Fontaine's stage II). The arterial and atheromatous origin of the disease was confirmed and localized by angiography or Doppler velocimetry examination. One hundred eighty-six patients were selected initially. Their pain-free walking distance on a treadmill (at a speed of 3 km/hour and an inclination of 10%) had to be 150-300 m. During the first month all patients received 3 placebo tablets daily. At the end of this run-in period (D-30; D 0) and after checking walking distance stability (allowed variation: +/- 20% between the two measurements) the patients were included in the study. One hundred fifty-four patients were selected and 118 remained during the whole study. The study was designed as a double-blind, using two parallel randomly selected groups. Sixty-four patients received for six months Naftidrofuryl (3 X 200 mg tablets daily with meals); 54 patients received placebo under the same conditions. During this period, clinical and paraclinical examinations were carried out every quarter (D 90 and D 180). After checking the initial homogeneity of the Naftidrofuryl and placebo-groups, the comparison between groups indicates a significant improvement in Naftidrofuryl group after 3 and 6 months of treatment. At the end of the study the observed differences in walking distance with Naftidrofuryl are approximately twice the difference in the reference group (D 90: p less than 0.05; D 180: p less than 0.02). The results of this study indicate that Naftidrofuryl is an efficient pharmacological tool for treatment of patients with chronic arterial disease (Fontaine's stage II).

The authors report a case of blunt traumatic rupture of the right ventricle, diagnosed during a laparotomy. Similar cases were seldom met: too short a time of spontaneous survival, and difficult challenging diagnosis explain it.

Endometriosis involving the digestive tract accounts for 1% of all cases of the disease. There is a marked predominance in the recto-sigmoid and terminal ileal loops. Symptomatology is dominated by disturbances in intestinal transit, sub-occlusion or acute obstruction, pain worsening at the time of menstruation and by a haemorrhagic rectal discharge again accompanying menstruation. Apart from classical aetiopathogenic theories such as grafting onto the digestive tract by tubal, lymph vessel or venous propagation, it would appear that prostaglandins and in particular a change in the (formula; see text) ratio may play a large role. Operative resection of localised stenosis combined with oophorectomy, if the latter is possible in view of the patient's age, or prolonged medical treatment with progestational agents or even better Danazol results in cure and avoids recurrences.

The authors analyse a series of 100 arterial lesions in respect to the localization, the time elapsed between the accident and reconstructive surgery, and the number of associated lesions (two or more). The results confirm the prognostic importance of the factor time: 83% of the good results are obtained in the first twelve hours, and only 67.5% after twelve hours. The results seen with popliteal and tibial lesions show a steady improvement from a 50% amputation rate twenty years ago to a 21.6% rate at the present time. The presence of associated lesions is equally important in the outcome: isolated arterial lesions (or accompanied by no more than two other anomalies) are successfully treated in 91% of the patients, opposed to 50% when loco-regional lesions are found (bone, skin, veins, nerves, muscles). The optional treatment of these complex traumatisms should be by means of a multidisciplinary approach.

Two subgroups in Natali and Thevenet's stage 0 class of asymptomatic diseases are defined. True asymptomatic affections occur in patients with neurologically asymptomatic carotid lesions. The natural history of these diseases when compared with results after surgery is in favor of preventive operative therapy. False asymptomatic affections are seen in patients who, after previous operations for symptomatic carotid lesions, present a lesion on the controlateral carotid which until then had been neurologically silent. The natural history of this group shows that immediate definitive cerebral accidents are rare and that life expectancy is low. In contrast, the course after repeat surgery, the present data being the first to be published, appears to be rather unfavorable. Careful selection of patients in this subgroup is therefore necessary when considering surgical treatment.