Concomitant Ring Research Articles

Skeletal Reorganization Emanated via the Course of Heterocyclic N1-N2 Bond Cleavage: Electrosynthetic Approach.

A unified method toward the synthesis of functionalized diazepines and quinazolines through reorganization of the molecular skeleton has been devised. The process is indulged by electrical energy via a domino N1-N2 bond cleavage followed by concomitant ring closing, initiating from cinnolines and indazoles as designed precursors. Additionally, an intermolecular ring homologation has also been established to synthesize densely functionalized dihydroquinazolines from 2,3-diaryl-indazoles and acetonitrile involving the same electrochemical strategy.

Fracture progression in fragility fractures of the pelvis: A case report

Introduction Fragility fractures of the pelvis (FFP) are becoming increasingly common as our population ages. Usually treated conservatively the concept of fracture progression is little recognized but can have important consequences for the patient if missed. Case report A patient with a FFP presented with increase of pain after initial conservative treatment. Additional imaging revealed extensive fracture progression resulting in an unstable pelvic ring, requiring surgical intervention. Most FFPs are currently treated conservatively. However, initially stable FFPs can progress into more unstable fracture patterns that may require invasive treatment. Conclusion Physicians should be aware of fracture progression and concomitant posterior ring fractures in case of prolonged or recurrent pain or mobilization difficulties. Careful follow-up and awareness might help to prevent or treat debilitation in an early phase and improve outcomes.

Mitral Valve Repair for Ischemic Mitral Regurgitation: The Jury Is Still Out

In this issue of The Annals of Thoracic Surgery, Fattouch and colleagues1 address a highly controversial matter that is as complex as it is multifactorial: the effect of ischemic mitral valve repair at the time of coronary revascularization. Their prospective randomized trial, albeit not devoid of important limitations, favors concomitant ring annuloplasty vs revascularization alone in terms of 10-year postoperative freedom from adverse events and left ventricular remodeling.

Internal fixation of acetabular quadrilateral plate fractures in elderly\xa0patients: Could the fracture reduction quality affect their\xa0functional recovery?

BackgroundOsteoporotic acetabular fractures frequently involve the quadrilateral plate (QP), a flat and thin bone constituting the medial wall of the acetabulum. This study aims to assess the impact of the quality of osteoporotic QP fractures reduction on the patients’ functional recovery, at 24 months follow-up.MethodsPatients referring with osteoporotic QP fractures to our Level I trauma centre were prospectively recruited. Inclusion criteria: patients aged 60 years old or older; osteoporosis, defined as Dual-energy X-ray Absorptiometry (DXA) T-score ≤ − 2.5; acute acetabular fracture; anatomic or good fracture reduction according to Matta on postoperative CT. Exclusion criteria: moderate cognitive impairment (defined as Mini-Mental State Examination < 19); a history of malignant neoplasm; concomitant fractures in other sites; traumatic head injury; lower limb joint prostheses; patient not able to walk independently before trauma; poor fracture reduction, according to Matta, on postoperative CT. All the QP fractures were surgically managed. After surgery, the reduction of each QP fracture was classified as anatomical (displacement 0–1 mm), good (displacement 2–3 mm) and poor (displacement > 3 mm) on postoperative CT. Based on this classification: patients with a poor fracture reduction were excluded from this study, patients with an anatomical reduction were recruited in Group-A and patients with a good reduction in Group-B. All the patients underwent a clinical and radiographic 24-months follow-up.Results68 patients (males 38; females 30; mean age 68.6 years old; range 60–79) were finally included in in the study. No cases of open fractures or concomitant pelvic ring fractures were observed. Based on the post-operative CT, 39 patients showed an anatomic fracture reduction (Group-A) while the remaining 29 patients revealed a good fracture reduction (Group-B). Complication rates and mean clinical scores showed no significant differences between groups, at 24-months follow-up.ConclusionsIn this study, the functional recovery at 24 months follow-up showed no significant differences in elderly patients with QP fracture undergoing anatomical reconstruction (displacement 0–1 mm) compared to patients receiving a good QP fracture reconstruction (displacement ≤ 3 mm).

Tandem Copper-Catalyzed Regioselective N-Arylation-Aza-Michael Addition: Synthesis of Tetracyclic 5H-Benzothiazolo[3,2-a]quinazoline Derivatives.

A copper-catalyzed tandem process integrating regioselective N-arylation, followed by aza-Michael addition, is disclosed using 2-aminobenzothiazoles and ortho-halo cinnamic acid congeners. This process generated diverse tetracyclic 5H-benzothiazolo[3,2-a]quinazoline derivatives in moderate to good yields. The present tandem reaction appears to proceed through concomitant ring opening of 2-aminobenzothiazole and S-arylation to give the ortho-cyanamide-substituted diaryl thioether intermediate. The thus generated intermediate likely undergoes an unprecedented Truce-Smiles-type rearrangement involving S- to N-aryl migration, followed by reformation of the thiazole ring and intramolecular aza-Michael addition to furnish the title products.

Ring-opening cyclization of activated spiro-aziridine oxindoles with heteroarenes: a facile synthetic approach to spiro-oxindole-fused pyrroloindolines.

Herein, we report a facile tandem approach for the synthesis of both spiro-oxindole-fused pyrroloindolines and benzofurano-pyrrolidines via a Lewis acid-catalyzed domino ring-opening with concomitant ring annulation using activated spiro-aziridines and heteroarenes. This method offers a new class of novel spiro-fused polycyclic pyrrolidines in a one-pot and sustainable manner with good yields and high diastereoselectivity. In addition, the structure of 3d was confirmed by single X-ray crystallography analysis.

Mitral valve repair using edge-to-edge technique in various situations: real-world experiences.

Edge-to-edge (E2E) mitral valve repair (MVP) is a versatile technique used in various situations for mitral regurgitation (MR). This technique has been regaining attention, given the increasing use of the MitraClip procedure. This real-world study evaluates the durability of the E2E technique in different settings. From January 2002 to May 2015, a total of 303 patients with at least moderate MR who underwent E2E MVP were identified. Patients undergoing isolated MVP (n = 133) and concomitant coronary artery bypass grafting or other valvular procedures (N = 170) were included. Cox proportional hazards modelling was used to evaluate the risk factors for cumulative survival, or MV event (i.e. MV reintervention or MR recurrence) while event-free survival-defined as time to composite outcome of either death or MV event-was determined using competing risk Kaplan-Meier analysis. Median follow-up duration was 6.9 (interquartile range 5.8) years. The most common MR aetiology was myxomatous (34%), followed by Barlow's disease (27.7%), and ischaemic (21.5%). E2E MVP was performed for the following indications: persistent MR (51.5%), systolic anterior motion prophylaxis (22.1%), transaortic approach (17.5%) and systolic anterior motion treatment post-MVP (8.9%). Concomitant ring annuloplasty was performed in 224 patients (73.9%). Operative mortality was 3.6% and MV event rate was 18.5%. Significant predictors of decreased survival included age, renal insufficiency, peripheral vascular disease and ischaemic MR aetiology (all P < 0.050). No ring annuloplasty (HR 2.79; P < 0.001) was the only significant predictor of MV events. Estimated event-free survival for the overall cohort was 8.5 years, and shortest for functional (non-ischaemic; 6.6 years) and ischaemic aetiology (5.5 years). E2E repair is a versatile MVP technique, which can be used in prevention and treatment of systolic anterior motion, transaortic approach or with concomitant techniques, with reasonable outcomes. Ischaemic aetiology and absence of ring annuloplasty were associated with worse cumulative survival and MV event rates, respectively, which raises some concern in light of the expanding indication for MitraClip system.

Copper-Mediated SN2' Allyl-Alkyl and Allyl-Boryl Couplings of Vinyl Cyclic Carbonates.

A method for the copper-catalyzed borylmethylation and borylation of vinyl cyclic carbonates through an SN2' mechanism is reported. These singular reactions involve selective SN2' allylic substitutions with concomitant ring opening of the cyclic carbonate and with extrusion of CO2 and formation of a useful hydroxyl functionality in a single step. The stereoselectivity of the homoallylic borylation and allylic borylation processes can be controlled, and synthetically useful unsaturated (E)-pent-2-ene-1,5-diols and (E)-but-2-ene-1,4-diols are accessed.

Structure-Activity Relationship Study Based on Autoinducing Peptide (AIP) from Dog Pathogen S. schleiferi.

Herein, an effective protocol for solid-phase synthesis of peptide thiolactones by concomitant ring closure and cleavage from the solid support is reported. The strategy was applied for mapping the importance of the structural features in S. schleiferi AIP (5) by performing an alanine scan and truncation of this natural compound. This furnished some of the most potent inhibitors of accessory gene regulator (agr)-I in the human pathogen S. aureus reported to date.

THE NATURE AND STRUCTURE OF PELVIC AREA DAMAGE IN PATIENTS WITH POLYTRAUMA ANDUNSTABLE PELVIC RING

The goal: to investigate the nature and structure of the pelvic area injury (PAI) in casualties with severe concomitant injury and unstable pelvic ring. The methods: the medical records of 406 casualties (157 survivors, 249 dead) with an unstable pelvis injury in polytrauma were analyzed. The severity of the injury was assessed according to the integral scales ISS, PTS, ATS. The con­clusion forensic examinations were studied for the dead. Results: among different types of injury traffic accident (245; 60.3 %) and household injuries (136; 33.5 %) were predominated, from point of view of injury genesis — catatrauma (150; 36.9 %). Unstable pelvic injuries in polytrauma were diagnosed more than half of patients with PAI with a predominance of rotationally unstable fractures (type B) — 307 (75.6 %). Vertically unstable lesions (type C) were observed in 99 (24.4 %) cases. Concomitant acetabular fractures were observed in 11.8 % of patients, damage to the pelvic organs (PO) — in 24.1%. Among PO following ruptures were detected: bladder — 48 (11.8 %), urethra — 27 (6.7 %), rectum — 5 (1.2 %),uterus and ovarian — 3 (0.7 %), great vessels — 5 (1.2 %), sev­eral PO — 10 (2.5 %). The severity of the damage of the different anatomical regions (AR) according to the scales ISS, PTS, ATS in group of survivors and deaths did not differ significantly (p > 0.05),but from the point of view of general severity of injury the dif­ferences between the groups were significant (p < 0.05). Lethal outcome was recorded in 249 cases (61.3 %). The greatest number of casualties died at 1–3 days post-injury — 185 cases (74.3 %); 4–10-days — 42 cases (16.9 %), 10 days after trauma and more — 22 cases (8.8%). In 72 28.9 %) cases, the results of forensic medical examination did not match the final diagnosis of damage severity of pelvic ring injury. Conclusions : unstable pelvic injury (type B and C) in patients with polytrauma was identified in 51.9 %of cases, while rotationally unstable fractures (type B) — 2/3. Vertically unstable fracture (type C) increases the risk of death by almost two times. Crucial to survival prognosis in polytrauma has a number of damaged AR due to the developmen t of mutual burdening syndrome.

Convenient syntheses of ring-B-nor analogues of Ambrox® and amberketal via a novel ring contraction reaction

Manool is converted into ring-B-nor analogues of commercially important perfumery compounds via a novel ring-B-nor intermediate methylene ketone 9. Compound 9 is synthesised via the formation of an exocyclic bromonium ion and the concomitant ring contraction of the B-ring of a diterpene skeleton derived from manool. Oxidation and base treatment of the ring-contracted product result in dehydrohalogenation and decarboxylation to afford methylene ketone compound 9, which is then converted to ring-B-nor analogues of Ambrox® and amberketal.

Surgical Treatment of Old Pelvic Ring and Lower Urinary Tract Injuries in Men

Surgical treatment results for 56 men with old pelvic bones and junctions injuries complicated or associated with either strictures or obliteration of membranous and bulbomembranous urethral segment are presented for the period from 2002 to 2013. Terms after trauma made up from 1 month to 6 years, mean age of patients - 36 (16-66) years. All patients were admitted with epicystoma and history of 3-5 failed surgical interventions directed to uresis restoration. The pattern of pathologic mobility, degree of pelvic ring injury, length of urethral defect, and connec- tion of urethra with either bone fragments or displaced pelvic bones were assessed during complex urologic and traumatologic examination. Treatment tactics, i.e. one- or two-step, was chosen depending on the diagnosed injuries. In two-step treatment tactics orthopaedic step always preceded the urologic one (urethra plasty) that followed in about 2 months after primary intervention. Observation terms made up from 1 month to 6 years. Loco-motor function was restored in all patients, urination - in 54 of 56 patients. Thus, elaborated method of surgical treatment for old concomitant pelvic ring and lower urinary tract injuries showed high efficacy in patients with posttraumatic urethral stricture or obliteration

Surgical Treatment of Old Pelvic Ring and Lower Urinary Tract Injuries in Men

Surgical treatment results for 56 men with old pelvic bones and junctions injuries complicated or associated with either strictures or obliteration of membranous and bulbomembranous urethral segment are presented for the period from 2002 to 2013. Terms after trauma made up from 1 month to 6 years, mean age of patients - 36 (16-66) years. All patients were admitted with epicystoma and history of 3-5 failed surgical interventions directed to uresis restoration. The pattern of pathologic mobility, degree of pelvic ring injury, length of urethral defect, and connec- tion of urethra with either bone fragments or displaced pelvic bones were assessed during complex urologic and traumatologic examination. Treatment tactics, i.e. one- or two-step, was chosen depending on the diagnosed injuries. In two-step treatment tactics orthopaedic step always preceded the urologic one (urethra plasty) that followed in about 2 months after primary intervention. Observation terms made up from 1 month to 6 years. Loco-motor function was restored in all patients, urination - in 54 of 56 patients. Thus, elaborated method of surgical treatment for old concomitant pelvic ring and lower urinary tract injuries showed high efficacy in patients with posttraumatic urethral stricture or obliteration

Rate of repair in minimally invasive mitral valve surgery.

Valve repair has been shown to be the method of choice in the treatment of patients with severe mitral valve regurgitation. Minimally invasive surgery has raised skepticism regarding the rate of repair especially for supposedly complex lesions, when anterior leaflet involvement or bileaflet prolapse is present. We sought to review our experience of all our patients presenting with degenerative mitral valve regurgitation and operated on minimally invasively. From September 2006 to December 2012, 842 patients (mean age 56.12±11.62 years old) with degenerative mitral valve regurgitation and anterior leaflet (n=82, 9.7%), posterior leaflet (n=688, 81.7%) and bileaflet (n=72, 8.6%) prolapses were operated on using a minimally invasive approach. 836 patients had a valve repair (99.3%) and received a concomitant ring annuloplasty (mean size, 33.7; range, 28-40). Six patients (0.7%) underwent valve replacement. Two patients had a re-repair due to MR progression or infective endocarditis. Thirty-day mortality was 0.2% (two patients). There were 60 major adverse events (MAE) (7.1%). A minimally invasive approach allows repair of almost all degenerative valves with good short-term outcomes in a tertiary referral center, when using proven and efficient surgical techniques.

OTITIS EXTERNA AND OTITIS MEDIA IN CATS IN ASSIUT: A RETROSPECTIVE STUDY OF PRESENTING SIGNS, CAUSES, DIAGNOSIS AND TREATMENT

In this study, records of cases admitted to the Small Animal Clinic (SAC), Veterinary Teaching Hospital (VTH) at Assiut University, between years 2007-2011 for investigation of signs of otitis were reviewed and data analyzed. Points of analysis comprised presenting clinical signs, results of otoscopic examination, identification of cause of otitis and outcome of treatment of each cat. Treatments used for these cases were either ivermectin injection or topical treatment with antimicrobial/anti-inflammatory ear drops as well as a ceruminolytic agent for cleansing the ear to increase effectiveness of medications used. Total number of cases with signs of otitis was 76 cats. Otitis cases comprised 19.8% of the total cases presented at the SAC in the study period. The most common presenting signs were head shaking, itching and ear wax in 67.11% of cases. 21.05% of cases were presented with severe inflammation, pain and alopecia around the ear pinna. A small number of cats were presented with signs of alopecia around the ear pinna and concomitant ring worm (3.95%). The remaining 7.89% were presented with very mild ear scratching in one or two ears. Sex was not a confounding factor as both males and females were equally represented among cases (51% males: 49% females). Turkish Angora and Persian cat breeds were over-represented (39.5% and 35.5% respectively). 68 cats were treated with ivermectin injections (1-4 injections) and ten cats were treated with topical antibacterial and anti-inflammatory. 67.11% of treated cases completely recovered and 32.89% of treated cases were not brought back for follow-up visits and therefore information regarding full recovery was not available. When evaluating a patient with otitis externa, it is important to determine the primary cause as well as the predisposing and perpetuating factors of the otitis so as to manage the otitis properly. The first diagnostic procedure that should be performed on a patient with a complaint of otitis externa is an otoscopic examination.

Facile ring cleavage of basic azetidines

Azetidines containing a basic ring nitrogen atom have been shown to undergo facile ring cleavage to afford 3-halo-1-amino propane derivatives upon exposure to alkyl bromides and acyl chlorides under certain conditions. The rate of ring cleavage appears to be determined largely by the rate at which quaternization of the azetidine nitrogen atom occurs. Alkylation of NH azetidines to afford N-alkyl azetidines can be carried out in synthetically useful yields if reaction times are kept short. As the free base, azetidines may undergo spontaneous oligomerization with concomitant ring cleavage.

ChemInform Abstract: Palladium‐Catalyzed Regioselective [3 + 2] Annulation of Internal Alkynes and Iodopyranoquinolines with Concomitant Ring Opening.

AbstractUnsymmetrical internal alkynes such as (X) or (XII) generate selectively a single isomers [cf.(XI) or (XIII)].

Palladium-Catalyzed Regioselective [3 + 2] Annulation of Internal Alkynes and Iodo-pyranoquinolines with Concomitant Ring Opening

A regioselective tandem synthesis of highly functionalized pyrrolo[1,2-a]quinolines has been developed through a novel strategy by palladium-catalyzed [3 + 2] annulation of iodo-pyranoquinolines and internal alkynes with subsequent ring opening. Pyranoquinoline with n-alkyl substitution at the 3-position leads to the formation of pyrrolo-acridones via [3 + 2] annulations/ring opening and successive intramolecular cross-aldol condensation.

The Rheumatic Mitral Valve and Repair Techniques in Children

The mitral valve is the most commonly affected valve in acute and chronic rheumatic heart disease in the first and second decades of life. Pure or predominant mitral regurgitation with non-significant stenosis (mitral valve area > 1.5 cm(2) on echocardiography) is the most frequently encountered valvular dysfunction in children. In our experience, based on 428 children operated between 1993 and 2011 at our institution, functional classification based on leaflet motion assessed by echocardiography and reconfirmed peroperatively revealed pure annulus dilatation (type I) in 7% of patients, anterior leaflet prolapse (type IIa) in 33%, combination of anterior leaflet pseudoprolapse with restricted motion of the posterior leaflet (type pseudoIIa/IIIp) in 34%, and restricted anterior and posterior leaflet motion (type IIIa/p) in 26%. Patients with type III were older than those with type IIa and type pseudoIIa/IIIp. Different techniques can be used to repair rheumatic mitral valve lesions: prolapse of the anterior leaflet caused by chordal elongation or rupture can be treated by chordal shortening, chordal transfer, or artificial chordal replacement; restricted motion of the anterior and/or posterior leaflet can be treated by commissurotomy, splitting of the papillary muscles, resection of the secondary, or sometimes primary posterior chordae, posterior leaflet free edge suspension, leaflet thinning, and leaflet enlargement using autologous pericardium. Because mitral annulus dilatation is present in almost all patients with mitral regurgitation, concomitant ring annuloplasty offers more stability in valve repair, improving long-term outcome. The major causes for failure of rheumatic mitral valve repair are the presence of ongoing rheumatic inflammation at the time of surgery, use of inappropriate techniques, technical failures requiring early reoperation, lack of concomitant ring annuloplasty, and progression of leaflet and chordal disease further resulting in more leaflet retraction, thickening, and deformity. Freedom from reoperation depends on mitral regurgitation functional type, the type IIa and type pseudoIIa/IIIp having a better long-term outcome than type I and type III, in our series. In conclusion, mitral valve repair should be a preferred strategy in children with rheumatic heart disease whenever feasible, providing stable actuarial survival with fewer thromboembolic complications in a pediatric population noncompliant to anticoagulation.

ChemInform Abstract: Ring-Enlarging Cyclopentene Annulations.

Abstract Ethynylation of 2-[(2,2-dialkoxy)ethyl]cycloalkanones followed by Lewis acid-promoted rearrangement occasions cyclopentene annulation with concomitant one-carbon ring expansion of the starting cycloalkanone.