ABSTRACT
Schwannomas are benign, encapsulated soft-tissue tumors that rarely present to the foot and ankle. These tumors are usually asymptomatic unless an increase in size or disruption of the nerve causes pain. We report a case of a painful mass along the lateral plantar nerve near the fourth metatarsal base that was surgically excised and confirmed as a benign schwannoma by means of histopathologic analysis. At the final follow-up of over 2 years, the patient reported no pain, neurologic deficits, or signs of recurrence. This case demonstrates an unusual location of a schwannoma arising from the lateral plantar nerve.
Subject(s)
Neurilemmoma , Soft Tissue Neoplasms , Ankle , Foot , Humans , Neoplasm Recurrence, Local , Neurilemmoma/diagnostic imaging , Neurilemmoma/surgeryABSTRACT
The field cycling NMR relaxometry method (also known as fast field cycling (FFC) when instruments employing fast electrical switching of the magnetic field are used) allows determination of the spin-lattice relaxation time (T1 ) continuously over five decades of Larmor frequency. The method can be exploited to observe the T1 frequency dependence of protons, as well as any other NMR-sensitive nuclei, such as (2) H, (13) C, (31) P, and (19) F in a wide range of substances and materials. The information obtained is directly correlated with the physical/chemical properties of the compound and can be represented as a 'nuclear magnetic resonance dispersion' curve. We present some recent academic and industrial applications showing the relevance of exploiting FFC NMR relaxometry in complex materials to study the molecular dynamics or, simply, for fingerprinting or quality control purposes. The basic nuclear magnetic resonance dispersion features are outlined in representative examples of magnetic resonance imaging (MRI) contrast agents, porous media, proteins, and food stuffs. We will focus on the new directions and perspectives for the FFC technique. For instance, the introduction of the latest Wide Bore FFC NMR relaxometers allows probing, for the first time, of the dynamics of confined surface water contained in the macro-pores of carbonate rock cores. We also evidence the use of the latest field cycling technology with a new cryogen-free variable-field electromagnet, which enhances the range of available frequencies in the 2D T1 -T2 correlation spectrum for separating oil and water in crude oil. Copyright © 2015 John Wiley & Sons, Ltd.
ABSTRACT
Novel bi-functional compounds with a nitric oxide (NO)-releasing moiety bound to a dorzolamide scaffold were investigated. Several compounds were synthesized and their activity as selective carbonic anhydrase inhibitors (CAI) evaluated in vitro on recombinant hCA type I, II and IV enzyme isoforms where they showed different degrees of potency and selectivity to hCA II. A high resolution X-ray crystal structure for the CA II adduct with 8 confirmed the high affinity of this class of compounds for the enzyme. Compounds 4, 6, and 8 showed highly potent and efficacious NO-mediated properties as assessed by their vascular relaxant effect on methoxamine-precontracted rabbit aortic rings. Finally, compounds 4 and 6 exerted potent intraocular pressure (IOP) lowering effects in vivo in normotensive rabbits thereby anticipating their potential for the treatment of hypertensive glaucoma.
Subject(s)
Carbonic Anhydrase II/antagonists & inhibitors , Carbonic Anhydrase Inhibitors/therapeutic use , Glaucoma, Open-Angle/drug therapy , Nitric Oxide/chemistry , Sulfonamides/therapeutic use , Thiophenes/therapeutic use , Animals , Carbonic Anhydrase Inhibitors/chemical synthesis , Carbonic Anhydrase Inhibitors/chemistry , Crystallography, X-Ray , Drug Discovery , Models, Molecular , Molecular Structure , Rabbits , Structure-Activity Relationship , Sulfonamides/chemical synthesis , Sulfonamides/chemistry , Thiophenes/chemical synthesis , Thiophenes/chemistryABSTRACT
Ketene dithioacetals undergo a Sharpless-type asymmetric oxidation using (+)-DET, Ti(O(i)()Pr)(4), and cumene hydroperoxide to give the trans bis-sulfoxides 4a-f with essentially complete control of enantioselectivity and diastereoselectivity. The high enantioselectivity is a consequence of carrying out two asymmetric processes on the same substrate. However, this should lead to the formation of a small amount of the meso isomer but none was isolated. From monitoring the enantioselectivity of the monoxide over time, it was concluded that small amounts of the meso isomer must be formed. The inability to isolate this compound could be because it acted as a ligand on titanium and remained tightly bound even upon workup.
