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Spontaneous Resolution (spontaneous + resolution)
Kinds of Spontaneous Resolution Selected AbstractsSyntheses, Spectroscopic Studies, and Crystal Structures of Chiral [Rh(aminocarboxylato)(,4 -cod)] and Chiral [Rh(amino alcohol)(,4 -cod)](acetate) Complexes with an Example of a Spontaneous Resolution of a Racemic Mixture into Homochiral Helix-EnantiomersEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 11 2006Mohammed Enamullah Abstract The dimeric complex acetato(,4 -cycloocta-1,5-diene)rhodium(I), [Rh(O2CMe)(,4 -cod)]2 (cod = cycloocta-1,5-diene), reacts with amino acids [HAA = L -alanine, (S)-2-amino-2-phenylacetic acid (L -phenylglycine), N -methylglycine, and N -phenylglycine] and with the amino alcohol (S)-2-amino-2-phenylethanol to afford the aminocarboxylato(,4 -cycloocta-1,5-diene)rhodium(I) complexes [Rh(AA)(,4 -cod)] (AA = deprotonated amino acid = aminocarboxylato ligand) and [(S)-2-amino-2-phenylethanol](,4 -cycloocta-1,5-diene)rhodium(I) acetate, [Rh{(S)-HOCH2,CH(Ph)-NH2}(,4 -cod)](O2CMe) (V). The complexes are characterized by IR, UV/Vis, 1H/13C NMR and mass spectroscopy. The achiral N -phenylglycine ligand gives a chiral N -phenylglycinato complex [Rh(O2C,CH2,NHPh)(,4 -cod)] (IV) with the amine nitrogen atom becoming the stereogenic center upon metal coordination. Complex IV crystallizes in the tetragonal, chiral space group P43 and the crystal structure reveals twofold spontaneous resolution of a racemic mixture into homochiral helix-enantiomers. The investigated crystal contained only one type of helix, namely (left-handed or M- ) 43 -helical chains. This is traced first to an intermolecular N,H···O hydrogen bonding from the stereogenic amino group to a neighboring unligated carboxyl oxygen atom that connects only molecules of the same (R)-configuration into (left-handed or M- ) 43 -helical chains. This intrachain homochirality is supplemented, secondly, by the interlocking of adjacent chains with their corrugated van der Waals surface to allow for an interchain transmission of the sense of helicity, building the single crystal from the same homochiral helix-enantiomer. The enantiomeric amino alcohol complex V crystallizes in the monoclinic, noncentrosymmetric (Sohncke) space group P21. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Spontaneous Resolution of Racemic Hydrogen-Bonded Nanoassemblies on Graphite Revealed by Atomic Force Microscopy,ADVANCED MATERIALS, Issue 16 2004H. Schönherr An atomic force microscopy (AFM) investigation into the spontaneous resolution of a P/M racemic mixture of helical self-assembled tetrarosettes 13·(DEB)12 (see Figure) into enantiopure domains in 2D supramolecular assemblies on highly oriented pyrolytic graphite (HOPG) is reported. These results represent the first reported case of spontaneous resolution of a racemate of chiral nanostructures. [source] Spontaneous Resolution of Type A Aortic DissectionJOURNAL OF CARDIAC SURGERY, Issue 6 2005Omar Mangoush F.R.C.S. We also discuss the possible mechanism and the role of conservative management in very selected group of patients. [source] Total Spontaneous Resolution of Five-Coordinate Complexes,ANGEWANDTE CHEMIE, Issue 32 2009Anders Lennartson Sauber getrennt: Mithilfe von Zink- und Cadmiumdiethyldithiocarbamaten gelang erstmals die Racematspaltung bei größeren Mengen an fünffach koordinierten Komplexen. Das stereochemische Ergebnis lässt sich durch Zugabe des gewünschten Isomers beeinflussen, was einen praktischen Zugang zu jedem Enantiomer mit hohem Enantiomerenüberschuss und hoher Ausbeute eröffnet. [source] ChemInform Abstract: From Racemic Compound to Spontaneous Resolution: A Linker-Imposed Evolution of Chiral [MnMo9O32]6- -Based Polyoxometalate Compounds.CHEMINFORM, Issue 51 2009Huaqiao Tan Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Breaking Symmetry: Spontaneous Resolution of a PolyoxometalateCHEMINFORM, Issue 8 2008Yu Hou Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Wedekind,Fock,Havinga Salt Me(Et)N+(All)PhI - ×CHCl3 as Historically the First Object for Absolute Asymmetric Synthesis: Spontaneous Resolution, Structure and Absolute Configuration.CHEMINFORM, Issue 28 2001Remir G. Kostyanovsky Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Spontaneous Resolution of Chiral Polyoxometalate-Based Compounds Consisting of 3D Chiral Inorganic Skeletons Assembled from Different Helical UnitsCHEMISTRY - A EUROPEAN JOURNAL, Issue 32 2008Ya-Qian Lan Dr. Abstract Four enantiomerically pure 3D chiral POM-based compounds, [Ni2(bbi)2(H2O)4V4O12],2,H2O (1,a and 1,b) and [Co(bbi)(H2O)V2O6] (2,a and 2,b) (bbi=1,1,-(1,4-butanediyl)bisimidazole) based on the achiral ligand, different vanadate chains, and different metal centers have been synthesized by hydrothermal methods. Single-crystal X-ray diffraction analyses revealed that 1,a and 1,b, and 2,a and 2,b, respectively, are enantiomers. In 1,a and 1,b two kinds of vanadate chains with different screw axes link Ni cations to generate 3D chiral inorganic skeletons, which are connected by the achiral bbi ligands to form complicated 3D 3,4-connected chiral self-penetrating frameworks with (72,8)(72,82,92)(73,82,10) topology. They represent the first examples of chiral self-penetrating frameworks known for polyoxometalate (POM) systems. Contrary to 1,a and 1,b, in 2,a and 2,b the vanadate chains link CoII cations to generate 3D chiral inorganic skeletons, which are assembled from two kinds of heterometallic helical units of opposite chirality along the c axes. The chiral inorganic skeletons are connected by bbi to form 3D 3,4-connected chiral POM-based frameworks with (62,8)2(62,82,102) topology. It is believed that the asymmetrical coordination modes of the metal cations in 1,a,2,b generate the initial chiral centers, and that the formation of the various helical units and the hydrogen bond interactions are responsible for preservation of the chirality and spontaneous resolution when the chirality is extended into the homochiral 3D-networks. This is the first known report of chiral POM-based compounds consisting of 3D chiral inorganic skeletons being obtained by spontaneous resolution upon crystallization in the absence of any chiral source, which may provide a rational strategy for synthesis of chiral POM-based compounds by using achiral ligands and POM helical units. [source] Breaking Symmetry: Spontaneous Resolution of a PolyoxometalateCHEMISTRY - A EUROPEAN JOURNAL, Issue 34 2007Yu Hou Abstract A chiral polyoxometalate [Hf(PW11O39)2]10, (1) has been prepared and structurally characterized. It crystallizes in the chiral space group P21212, as a conglomerate of two enantiomerically pure crystals in the absence of any chiral source. The absolute configuration of 1 was determined from the Flack parameter by X-ray crystallography. The structure of 1 comprises two lacunary [PW11O39]7, units, each functioning as a tetra-dentate ligand sandwiching an 8-coordinate HfIV centre in a distorted square antiprismatic geometry. Optically active crystals of both enantiomers were spectroscopically distinguishable by means of solid state circular dichroism spectroscopy. This hafnium-substituted polyoxometalate (POM), 1, shows that spontaneous chiral resolution, a rare phenomenon, can be operable in POM systems. [source] Total Spontaneous Resolution of Chiral Covalent Networks from Stereochemically Labile Metal ComplexesCHEMISTRY - A EUROPEAN JOURNAL, Issue 18 2005Anna Johansson Abstract Stereochemically labile copper and zinc complexes with the N,N, -dimethylethylenediamine ligand (dmeda) have been shown to be promising precursors for the total spontaneous resolution of chiral covalent networks. (N,N,)-[Cu(NO3)2(dmeda)], crystallises as a conglomerate and yields either enantiopure (R,R)- 1 or enantiopure (S,S)- 1. A mixed-valence copper(I/II) complex, [{CuIIBr2(dmeda)}3(CuIBr)2], (2), which crystallises as a pair of interpenetrating chiral (10,3)- a nets, is formed from CuBr, CuBr2 and dmeda. One net contains ligands with solely (R,R) configuration and exhibits helices with (P) configuration while the other has solely (S,S)-dmeda ligands and gives rise to a net in which the helices have (M) configuration. The whole crystalline arrangement is racemic, because the interpenetrating chiral nets are of opposite handedness. With zinc chloride (R,S)-[ZnCl(dmeda)2]2[ZnCl4] (3) is obtained, which is a network structure, although not chiral. Total spontaneous resolution of stereochemically labile metal complexes formed from achiral or racemic building blocks is suggested as a viable route for the preparation of covalent chiral networks. Once the absolute structure of the compound has been determined by X-ray crystallography, a quantitative determination of the enantiomeric excess of the bulk product can be undertaken by means of solid-state CD spectroscopy. [source] The characteristics and outcome of primary vesicoureteric reflux diagnosed in the first year of lifeINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 7 2006F. Papachristou Summary A retrospective trial was performed to study presentation, evaluation, management, complications and outcome of 186 infants with vesicoureteral reflux (VUR). Medical records of 103 male and 83 female infants with mean age at entry 5.97 months were reviewed. Diagnosis was established using radiographic voiding cystourethrogram. At diagnosis, a renal ultrasound and dimercaptosuccinic acid renal scintigraphy were performed in all children. The follow-up included blood pressure measurements, serial urine cultures, haematological and biochemical tests, radionuclide cystography, renal ultrasounds and renal scintigraphy. The majority of infants with reflux, 176/186, presented with one or more episodes of urinary tract infections. In 113 children, reflux resolved spontaneously, 27 underwent surgical or endoscopic correction and 46 are being followed-up to date. Spontaneous resolution after prophylaxis was more frequent in boys (p < 0.0001), in children with grade I or II (p < 0.0001) and unilateral reflux at diagnosis (p = 0.0215). No significant difference could be established with respect to the presence of scars (p = 0.1680) and the number of breakthrough urinary tract infections (p = 0.1078). The data of the present study indicate that spontaneous resolution rate is high in infants, and therefore, early antireflux surgery should be avoided. [source] Spontaneous resolution of a delayed granulomatous reaction to cosmetic tattooINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 1 2008Brad Jones MBBS, MPhil(Path) A 27-year-old woman presented with linear, flesh-colored papules along her vermillion borders, 4 years after a cosmetic lip tattoo was applied. A biopsy of the lesion was performed and histology showed it to be a granulomatous reaction surrounding the tattoo pigment. Following the biopsy, the lesions began to resolve spontaneously within 4 weeks and were not noticeable at a follow-up review. Granulomatous reactions are rare after cosmetic facial tattoos and may respond to topical corticosteroids or laser ablation. We present a unique report of a delayed granulomatous reaction to a cosmetic tattoo completely resolving without any specific treatment. [source] Spontaneous resolution of acquired factor V inhibitor associated with ovarian carcinomaINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2007E. O. MAUGHAN Summary A 74-year-old lady who presented initially with loin pain and haematuria, then melaena was found to have a prothrombin time ratio (PTR) > 10 and activated partial thromboplastin time ratio (APTTR) > 7. A factor V inhibitor was diagnosed. She was managed with supportive care and the FV inhibitor resolved. A few weeks later she developed abdominal swelling and ascites and was found to have an ovarian tumour. This is the first case, as far as we are aware, of a malignancy-associated FV antibody that has spontaneously remitted before overt presentation of the tumour and illustrates the value of adopting an expectant approach to the management of acquired FV inhibitors. [source] Erythema multiforme along Blaschko's linesJOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 3 2000Claudia Micalizzi Abstract A case of erythema multiforme along Blaschko's lines is reported in a 20-year-old female suffering from recurrent herpes labialis. Histological examination was compatible with the clinical features. Spontaneous resolution followed in 4 weeks without therapy. [source] Spontaneous resolution of hypothermia-induced atrial fibrillation in a dogJOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, Issue 4 2004Scott A. Campbell DVM Abstract Objective: To report a case of spontaneous resolution of atrial fibrillation secondary to hypothermia in a dog without detectable heart disease. Case summary: An 8-year-old female spayed mixed breed dog presented with a history of prolonged exposure to below freezing environmental temperatures. The dog presented hypothermic (<32°C or <90°F) and minimally responsive to stimuli. The heart rate was 80 beats per minute (bpm) and irregular. Atrial fibrillation was diagnosed. The dog had pale mucous membranes, absent femoral pulses, and no obtainable blood pressure via indirect Doppler technique. Resuscitation fluids were administered and active external warming was instituted. Peripheral edema was observed during the rewarming phase and the irregular heart rate was noted to increase. The atrial fibrillation spontaneously resolved with no specific anti-arrhythmic therapy. No underlying myocardial disease was found. The recovery of this dog was complete with a subsequent repeat of the echocardiogram and electrocardiogram (ECG) 8-months later found to be within normal limits. [source] Improvement in hepatopulmonary syndrome after methadone withdrawal: A case report with implications for disease mechanismLIVER TRANSPLANTATION, Issue 7 2010Edmund M. T. Lau Spontaneous resolution of hepatopulmonary syndrome (HPS) without liver transplantation or improvement in the underlying liver disease has rarely been reported in the literature. Increased endogenous production of nitric oxide has been implicated in the pathogenesis of HPS. We report the case of a 50-year-old man with hepatitis C cirrhosis who demonstrated dramatic improvement in HPS after withdrawal from chronic methadone therapy. We speculate on the potential role of opiate receptors in the pulmonary vasculature and their effect on nitric oxide signaling as a potential mechanism accounting for the patient's clinical improvement. Liver Transpl 16:870,873, 2010. © 2010 AASLD. [source] Spontaneous resolution of Epstein,Barr virus-associated hemophagocytic lymphohistiocytosis,PEDIATRIC BLOOD & CANCER, Issue 4 2010Brian Belyea MD Abstract Secondary hemophagocytic lymphohistiocytosis (sHLH) is a reactive, proliferative disorder of the immune system resulting in lymphohistiocytic proliferation, hemophagocytosis, and cytokine dysregulation. The most common infectious trigger in sHLH is Epstein,Barr virus (EBV-HLH). Current treatment protocols for EBV-HLH have a cure rate of approximately 75%; however, there are significant toxicities associated with these therapies. We present two patients with EBV-HLH who experienced spontaneous resolution of their disease prior to the initiation of therapy, suggesting there may be a subgroup of patients with EBV-HLH who do well with conservative management and can avoid potentially toxic therapies. Pediatr Blood Cancer. 2010;55:754,756. © 2010 Wiley-Liss, Inc. [source] Spontaneous resolution of diffuse persistent pulmonary interstitial emphysemaPEDIATRIC PULMONOLOGY, Issue 6 2008Mandeep S. Jassal MD Abstract Persistent pulmonary interstitial emphysema (PPIE) is a rare condition that occurs in both preterm and term infants. It is thought to arise from a disruption of the basement membrane of the alveolar wall allowing air entry into the interstitial space. The characteristic CT scan appearance of PPIE can be used to differentiate it from other congenital cystic lesions that may present similarly. Although conservative management is accepted as the initial form of management in most cases, a review of the published literature found that a significant proportion of localized PPIE cases eventually require surgical resection. This case illustrates that extensive bilateral PPIE associated with a persistent pneumomediastinum can resolve spontaneously thus demonstrating that conservative management without surgical intervention may be appropriate for some children. Pediatr Pulmonol. 2008; 43:615,619. © 2008 Wiley-Liss, Inc. [source] Spontaneous resolution (and other rarities) of gallstone ileusANZ JOURNAL OF SURGERY, Issue 12 2009Arkadiusz Peter Wysocki MBBS, FRACS No abstract is available for this article. [source] Spontaneous resolution in a case of pseudo-pseudoxanthoma elasticumBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2001H. Sueki No abstract is available for this article. [source] Syntheses, Spectroscopic Studies, and Crystal Structures of Chiral [Rh(aminocarboxylato)(,4 -cod)] and Chiral [Rh(amino alcohol)(,4 -cod)](acetate) Complexes with an Example of a Spontaneous Resolution of a Racemic Mixture into Homochiral Helix-EnantiomersEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 11 2006Mohammed Enamullah Abstract The dimeric complex acetato(,4 -cycloocta-1,5-diene)rhodium(I), [Rh(O2CMe)(,4 -cod)]2 (cod = cycloocta-1,5-diene), reacts with amino acids [HAA = L -alanine, (S)-2-amino-2-phenylacetic acid (L -phenylglycine), N -methylglycine, and N -phenylglycine] and with the amino alcohol (S)-2-amino-2-phenylethanol to afford the aminocarboxylato(,4 -cycloocta-1,5-diene)rhodium(I) complexes [Rh(AA)(,4 -cod)] (AA = deprotonated amino acid = aminocarboxylato ligand) and [(S)-2-amino-2-phenylethanol](,4 -cycloocta-1,5-diene)rhodium(I) acetate, [Rh{(S)-HOCH2,CH(Ph)-NH2}(,4 -cod)](O2CMe) (V). The complexes are characterized by IR, UV/Vis, 1H/13C NMR and mass spectroscopy. The achiral N -phenylglycine ligand gives a chiral N -phenylglycinato complex [Rh(O2C,CH2,NHPh)(,4 -cod)] (IV) with the amine nitrogen atom becoming the stereogenic center upon metal coordination. Complex IV crystallizes in the tetragonal, chiral space group P43 and the crystal structure reveals twofold spontaneous resolution of a racemic mixture into homochiral helix-enantiomers. The investigated crystal contained only one type of helix, namely (left-handed or M- ) 43 -helical chains. This is traced first to an intermolecular N,H···O hydrogen bonding from the stereogenic amino group to a neighboring unligated carboxyl oxygen atom that connects only molecules of the same (R)-configuration into (left-handed or M- ) 43 -helical chains. This intrachain homochirality is supplemented, secondly, by the interlocking of adjacent chains with their corrugated van der Waals surface to allow for an interchain transmission of the sense of helicity, building the single crystal from the same homochiral helix-enantiomer. The enantiomeric amino alcohol complex V crystallizes in the monoclinic, noncentrosymmetric (Sohncke) space group P21. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Maternal-infant transmission of hepatitis C virus infectionHEPATOLOGY, Issue 5B 2002Eve A. Roberts 555 University Ave. Mother-to-infant transmission of hepatitis C virus (HCV) is comparatively uncommon. The prevalence of antibody to HCV (anti-HCV) in pregnant women is 0.1% to 2.4%, although in some endemic areas it is much higher. The proportion of women with anti-HCV who have active infection with viremia is 60% to 70%. Transmission of HCV occurs only when serum HCV RNA is detectable and may be related to higher levels (above 106 copies per mL). The rate of mother-to-infant transmission is 4% to 7% per pregnancy in women with HCV viremia. Co-infection with human immunodeficiency virus (HIV) increases the rate of transmission 4 to 5 fold. The actual time and mode of transmission are not known. Elective Cesarean section is not recommended for women with chronic HCV infection alone. The role of treatment to prevent transmission is limited by the fetal toxicity of currently available medications for hepatitis C. Breast feeding poses no important risk of HCV transmission if nipples are not traumatized and maternal hepatitis C is quiescent. Pregnant women at high risk for HCV infection should be screened for anti-HCV, and HCV RNA testing should be performed if anti-HCV is positive. Infants of women with hepatitis C should be tested for HCV RNA on two occasions, between the ages of 2 and 6 months and again at 18 to 24 months, along with serum anti-HCV. The natural history of mother-to-infant hepatitis C remains uncertain, especially the course in the first year of life when some infants appear to have spontaneous resolution. [source] Tissue inhibitor of metalloproteinases-1 attenuates spontaneous liver fibrosis resolution in the transgenic mouseHEPATOLOGY, Issue 4 2002Hitoshi Yoshiji It has been suggested that the tissue inhibitor of metalloproteinases-1 (TIMP-1) is involved in spontaneous resolution of liver fibrosis. The aim of this study was to investigate whether TIMP-1 altered spontaneous resolution of liver fibrosis in conjunction with matrix metalloproteinases (MMP) inhibition and hepatic stellate cell (HSC) activation. The livers of liver-targeted TIMP-1 transgenic (TIMP-Tg) and control hybrid (Cont) mice were harvested at 0, 3, 7, and 28 days following spontaneous recovery from CCl4 -induced liver fibrosis. The extent of fibrosis resolution, MMP expression, ,-smooth-muscle actin (,-SMA) positive cells, and procollagen-(I) messenger RNA (mRNA) in the liver were assessed at the respective periods in both groups. We also examined the effect of TIMP-1 on HSC apoptosis. The TIMP-Tg mice showed significantly attenuated resolution of spontaneous liver fibrosis compared with the Cont mice. The hydroxyproline content, number of ,-SMA positive cells, and procollagen-(I) mRNA rapidly decreased with time in the Cont mice, whereas these markers were little changed in TIMP-Tg mice. The level of the active form of metalloproteinases-2 (MMP-2) in the TIMP-Tg mice was less than that in the Cont mice. TIMP-1 markedly decreased the nonparenchyma apoptotic cells in the liver fibrosis resolution model, and it also inhibited HSC apoptosis associated with suppression of caspase-3 activity in vitro. In conclusion, TIMP-1 significantly attenuated spontaneous resolution of liver fibrosis by the combination of a net reduction of the MMP activity and suppression of apoptosis in HSC. [source] Spontaneous Resolution of Racemic Hydrogen-Bonded Nanoassemblies on Graphite Revealed by Atomic Force Microscopy,ADVANCED MATERIALS, Issue 16 2004H. Schönherr An atomic force microscopy (AFM) investigation into the spontaneous resolution of a P/M racemic mixture of helical self-assembled tetrarosettes 13·(DEB)12 (see Figure) into enantiopure domains in 2D supramolecular assemblies on highly oriented pyrolytic graphite (HOPG) is reported. These results represent the first reported case of spontaneous resolution of a racemate of chiral nanostructures. [source] One-Step Synthesis of Chiral Azamacrocycles via Palladium-Catalyzed Enantioselective Amination of 1,5-Dichloroanthraquinone and 1,5-DichloroanthraceneADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 13 2010Elena R. Ranyuk Abstract Asymmetric amination of 1,5-dichloroanthraquinone and 1,5-dichloroanthracene with di- and trioxadiamines catalyzed by palladium complexes with various chiral phosphine ligands gave chiral macrocycles with ee values of up to 60%. The dependence of the chemical yields and enantiomeric excess on the nature of the starting compounds and the phosphine ligands employed was demonstrated. An unexpected spontaneous resolution upon crystallization of the macrocycle comprising anthraquinone and dioxadiamine moieties was observed while in the case of the macrocycle with a trioxadiamine linker racemic monocrystals were obtained. Crystallization of the enantiomerically enriched mixtures afforded chiral macrocycles with 88,99% ee. [source] Proarrhythmia of Circumferential Left Atrial Lesions for Management of Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2006EMILE G. DAOUD M.D. Background: After circumferential ablation for atrial fibrillation, new onset left atrial flutter (LA Flr) may occur. This study assessed the relationship between induced and clinical episodes of LA Flr, the rate of spontaneous resolution of LA Flr, and the proarrhythmic effect of circumferential ablation. Methods and Results: A total 112 patients underwent circumferential LA ablation for atrial fibrillation. Immediately after completion of the ablation, LA Flr was induced in 43 of 112 (38%) patients, but was not targeted for ablation. During follow-up (14 ± 4 months), new onset LA Flr occurred in 28 of 112 (25%) patients; however, the presence of inducible LA Flr did not identify those patients with clinical LA Flr (P = 0.6). In comparison to episodes of atrial fibrillation occurring before circumferential ablation, LA Flr was associated with a faster ventricular rate (124 ± 19 beats/min vs 91 ± 16 beats/min, P < 0.001), and was more likely to be persistent requiring cardioversion (86% vs 32%, P = 0.01). By ,4 months postcircumferential ablation, clinical LA Flr resolved in 18 of 28 patients (64%). A second ablation procedure for LA Flr was performed in 9 of 10 patients. Of the 17 morphologies, 16 (94%) LA Flr circuits were successfully ablated. Conclusions: (1) LA Flrs that are induced immediately after circumferential ablation for atrial fibrillation do not identify those patients who require a second ablation procedure for clinical LA Flr; (2) Since the majority of clinical LA Flrs spontaneously resolve, ablation of LA Flr should be postponed several months; and (3) new onset LA Flr after ablation for atrial fibrillation is likely a manifestation of the proarrhythmic effect of ablation lines in the LA. [source] Conservative management of an extensive renal graft subcapsular hematoma arising during living donor nephrectomy.JOURNAL OF CLINICAL ULTRASOUND, Issue 3 2010Role of Doppler sonographic posttransplant follow-up Abstract We report a case of subcapsular hematoma (SH) of a kidney graft arising during minimal-incision living-donor nephrectomy. SH covered at least two-thirds of the cortical surface. Capsulotomy was not done because it was deemed too risky. In the immediate postoperative period, a rapid deterioration of graft function was observed associated with Doppler sonographic evidence of graft compression. However, in the following days, spontaneous resolution of SH and progressive improvement of Doppler findings was observed, which preceded full recovery of graft function. Conservative management seemed a valid approach of this complication in this case where Doppler sonography proved essential for the follow-up. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2010 [source] Factors predicting successful outcome following neostigmine therapy in acute colonic pseudo-obstruction: A prospective studyJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 2 2006RAJIV MEHTA Abstract Aim:, To evaluate predictors of neostigmine response in patients with acute colonic pseudo-obstruction. Methods:, Twenty-seven patients with acute colonic pseudo-obstruction were enrolled in the study. All patients had received initial conservative management such as nil orally, nasogastric suction, rectal tube placement and correction of electrolyte imbalance for the first 24 h. Those who did not resolve with conservative management received 2 mg neostigmine intravenously. The same dose was repeated after 24 h in patients who did not response to the first dose (initial non-responders), or in those patients who relapsed after an initial response (initial responders). All non-responders to neostigmine underwent colonoscopic decompression followed by 2 mg neostigmine infusion for 30 min. A sustained response was defined as the resolution of symptoms and colonic dilatation on a plain radiograph. Results:, The study enrolled 27 patients; 18 were male (67%), and the median age was 60 years (range 18,78 years). Eight (30%) patients had spontaneous resolution. Initial response with neostigmine was observed in 16 (84%) patients, of which 10 (63%) had a sustained response. Nine patients (three initial non-responders and six initial responders) had received a second dose of neostigmine. A sustained response was seen only in five initial responders. Four patients who did not respond to neostigmine underwent colonoscopic decompression followed by neostigmine infusion and had a sustained response. Neostigmine responders were more likely to be postoperative patients (11 of 15 (73%) vs one of four (25%), P = 0.07), less likely to have electrolyte imbalance and to be on antimotility agents (three of 15 (20%) vs four of four (100%), P = 0.009 and two of 15 (13%) vs four of four (100%), P = 0.003). Conclusions:, Electrolyte imbalance and usage of anti-motility agents are factors associated with a poor response, while postoperative patients showing good response to neostigmine therapy. [source] Oral lichen planus: a condition with more persistence and extra-oral involvement than suspected?JOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 10 2008Marta Bidarra Background:, Lichen planus is a relatively common and often studied chronic mucocutaneous condition. Reports detailing certain aspects relevant to patients affected have been lacking or inconsistent. Methods:, A questionnaire-based survey was employed to assess the duration of oral lesions and the prevalence of self-reported potential extra-oral manifestations associated with oral lichen planus in 87 patients. All patients had recognized clinical features of oral lichen planus, and most had had histopathological confirmation following oral biopsy. Results:, We report the findings of a preliminary survey which assessed the duration of oral lesions and the prevalence of extra-oral lesions consistent with lichen planus in patients presenting with oral lesions. The study confirmed the chronic nature of oral lichen planus and the rarity of spontaneous resolution. Most subjects had experienced symptoms for one to ten years (66 patients; 75.8%). Approximately 40% (36 patients) of the sample reported clinical features suggestive of extra-oral manifestations of lichen planus by the time that their oral lesions were apparent. The most commonly reported extra-oral manifestations involved the nails (27.6%, 24 patients). 25.3% (22 patients) reported a persistently sore throat suggestive of oesophageal or pharyngeal involvement. Skin (17.2%, 11 patients), and genital (10.3%, 9 patients) involvement was relatively infrequently reported. Most patients reported extra-oral lesions at only one site. Conclusions:, The survey results suggest that in patients with oral lichen planus oral lesions persist for a prolonged period, and that extra-oral lesions may be more common than suspected. However, further studies involving specialists to examine extra-oral sites are required. [source] Spontaneous resolution of hypothermia-induced atrial fibrillation in a dogJOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, Issue 4 2004Scott A. Campbell DVM Abstract Objective: To report a case of spontaneous resolution of atrial fibrillation secondary to hypothermia in a dog without detectable heart disease. Case summary: An 8-year-old female spayed mixed breed dog presented with a history of prolonged exposure to below freezing environmental temperatures. The dog presented hypothermic (<32°C or <90°F) and minimally responsive to stimuli. The heart rate was 80 beats per minute (bpm) and irregular. Atrial fibrillation was diagnosed. The dog had pale mucous membranes, absent femoral pulses, and no obtainable blood pressure via indirect Doppler technique. Resuscitation fluids were administered and active external warming was instituted. Peripheral edema was observed during the rewarming phase and the irregular heart rate was noted to increase. The atrial fibrillation spontaneously resolved with no specific anti-arrhythmic therapy. No underlying myocardial disease was found. The recovery of this dog was complete with a subsequent repeat of the echocardiogram and electrocardiogram (ECG) 8-months later found to be within normal limits. [source] | |||||||||||||||||||||||||||||||