Heme compound II models bearing electron-deficient and -rich porphyrins, [Fe(O)(TPFPP)(Cl)] (1a) and [Fe(O)(TMP)(Cl)] (2a), respectively, are synthesized, spectroscopically characterized, and investigated in chemoselectivity and disproportionation reactions using cyclohexene as a mechanistic probe. Interestingly, cyclohexene oxidation by 1a occurs at the allylic C-H bonds with a high kinetic isotope effect (KIE) of 41, yielding 2-cyclohexen-1-ol product; this chemoselectivity is the same as that of nonheme iron(iv)-oxo intermediates. In contrast, as observed in heme compound I models, 2a yields cyclohexene oxide product with a KIE of 1, demonstrating a preference for C[double bond, length as m-dash]C epoxidation.
View Article and Find Full Text PDFPost-traumatic portal venous thrombosis is a rare event, and is usually seen in association with penetrating injuries. Portal venous thrombosis following blunt abdominal trauma is extremely rare with only few reports in the literature, some associated with underlying coagulation disorders. We report multidetector computed tomography findings in a case of blunt abdominal trauma with otherwise normal coagulation profile, which showed shattered spleen and MDCT evidence of acute thrombosis in the right branch of the portal vein.
View Article and Find Full Text PDFActivation of dioxygen (O) in enzymatic and biomimetic reactions has been intensively investigated over the past several decades. More recently, O-O bond formation, which is the reverse of the O-activation reaction, has been the focus of current research. Herein, we report the O-activation and O-O bond formation reactions by manganese corrole complexes.
View Article and Find Full Text PDFBackground: Robert's uterus is a very rare müllerian duct anomaly which is characterised by septate uterus with obstruction of a one-sided cavity and formation of hematometra. Therefore, patients present with cyclical abdominal pain during menstruation along with normal menstrual flow.
Case Report: We present magnetic resonance imaging (MRI) findings in a case of Robert's uterus in a young woman.
The rate constants of the C═C epoxidation and the C-H hydroxylation (i.e., allylic C-H bond activation) in the oxidation of cyclohexene by a high-valent iron(IV)-oxo porphyrin π-cation radical complex, [(TMP)Fe(O)(Cl)] (1, TMP = meso-tetramesitylporphyrin dianion), were determined at various temperatures by analyzing the overall rate constants and the products obtained in the cyclohexene oxidation by 1, leading us to conclude that reaction pathway changes from the C═C epoxidation to C-H hydroxylation by decreasing reaction temperature.
View Article and Find Full Text PDFBackground: Portal annular pancreas is a rare pancreatic developmental anomaly which is often overlooked at imaging, and often diagnosed retrospectively when it is detected incidentally at the time of surgery. Although the anomaly itself is asymptomatic, it becomes important in cases where pancreatic resection/anastomosis is planned, because of varying ductal anatomy, risk of ductal injury and increased risk of postoperative pancreatic fistula formation.
Case Report: We present imaging findings in a case of portal annular pancreas in a 45-year-old male patient.
Introduction: Multidetector Computed Tomography (MDCT) provides clinically and surgically important information in bowel obstruction. It can depict the severity, level and cause of obstruction.
Aim: To depict the spectrum of MDCT findings in cases of small and large bowel obstruction.
Introduction: Magnetic resonance imaging (MRI) is the modality of the first choice for evaluation of vertebral compression/collapse. Many MRI qualitative features help to differentiate benign from malignant collapse. We conducted this study to look for a quantitative difference in chemical shift values in benign and malignant collapse using dual-echo gradient echo in-phase/out-phase imaging.
View Article and Find Full Text PDFAim: To compare the retentive ability and deformation of Acetal resin with Cobalt-Chromium clasps via Insertion Removal apparatus after subjecting them to stimulate clinical use.
Materials And Methods: Materials used for this study are commercially available Cobalt-Chromium alloy namely Wironit, Bego, Germany and Acetal resin namely Biodentaplast, Bredent, Germany. The test samples were divided into two major groups based on the type of materials used in the study.
Acquired Dyke-Davidoff-Masson syndrome, also known as hemispheric atrophy, is characterized by loss of volume of one cerebral hemisphere from an insult in early life. Crossed cerebellar diaschisis refers to dysfunction/atrophy of cerebellar hemisphere which is secondary to contralateral supratentorial insult. We describe magnetic resonance imaging findings in two cases of acquired Dyke-Davidoff-Masson syndrome with crossed cerebro-cerebellar diaschisis.
View Article and Find Full Text PDFJ Craniovertebr Junction Spine
March 2015
Introduction: Back pain is a common clinical problem and is the frequent complaint for referral of lumbar spine magnetic resonance imaging (MRI). Coronal short tau inversion recovery sequence (STIR) can provide diagnostically significant information in small percentage of patients.
Materials And Methods: MRI examinations of a total of 350 patients were retrospectively included in the study.
Introduction: Spinal trauma is relatively more common in young active individuals. Although its mortality is low, it is an important cause of long term disability. Magnetic resonance imaging (MRI) can accurately depict presence and extent of spinal cord injury (SCI) in these patients.
View Article and Find Full Text PDFA broad ligament pregnancy is an extremely rare condition. Diagnosis is often missed and finally made during laparotomy. We present a case which remained undiagnosed throughout her pregnancy till she reached term and unfortunately had intrauterine foetal demise when she reported to our hospital.
View Article and Find Full Text PDFIndian J Radiol Imaging
April 2013
Cystic adventitial disease of popliteal artery is a rare condition of unknown etiology which usually presents in middle-aged men. We present Doppler and computed tomography angiography findings in a case of cystic adventitial disease with significant obstruction of popliteal artery, with secondary narrowing of popliteal vein.
View Article and Find Full Text PDFSnakebite is an important and serious medical problem throughout the entire terai region of Nepal. But comprehensive study of snakebite epidemiology in Western Development Region of Nepal is scarce. We described the status of snakebite situation in the region based on retrospective data retrieved from 10 snakebite treatment centers during June 2011 to February 2012.
View Article and Find Full Text PDFJ Emerg Trauma Shock
July 2012
Aorto-esophageal fistula (AEF) is a rare and life threatening condition, which can be rapidly fatal. More than half of such cases are secondary to aortic aneurysm rupture. There are only two previous reports describing AEF caused by penetrating atherosclerotic ulcer.
View Article and Find Full Text PDFIndian J Gastroenterol
December 2011