MR Imaging Features of Middle Cranial Fossa Encephaloceles and Their Associations with Epilepsy.

BACKGROUND AND PURPOSE: Middle cranial fossa encephaloceles are an increasingly recognized cause of epilepsy; however, they are also often encountered on neuroimaging in patients with no history of seizure. We characterized the MR imaging features of middle cranial fossa encephaloceles in seizure and nonseizure groups with the hope of uncovering features predictive of epileptogenicity. MATERIALS AND METHODS: Seventy-seven patients with middle cranial fossa encephaloceles were prospectively identified during routine clinical practice of neuroradiology at a tertiary care hospital during an 18-month period. Thirty-five of 77 (45%) had a history of seizure, 20/77 (26%) had temporal lobe epilepsy, and 42/77 (55%) had no history of seizures. Middle cranial fossa encephalocele features on MR imaging were characterized, including depth, area, number, location, presence of adjacent encephalomalacia, and degree of associated parenchymal morphologic distortion. MR imaging features were compared between the seizure and nonseizure groups. RESULTS: No significant difference in MR imaging features of middle cranial fossa encephaloceles was seen when comparing the seizure and nonseizure groups. Comparison of just those patients with temporal lobe epilepsy (n = 20) with those with no history of seizure (n = 42) also found no significant difference in MR imaging features. CONCLUSIONS: Anatomic MR imaging features of middle cranial fossa encephaloceles such as size, number, adjacent encephalomalacia, and the degree of adjacent parenchymal morphologic distortion may not be useful in predicting likelihood of epileptogenicity.

Crystal structures and solution behavior of paramagnetic divalent transition metal complexes (Fe, Co) of the sterically encumbered tridentate macrocycles 1,4,7-R3-1,4,7-triazacyclononane: coordination numbers 5 (R = i-Pr) and 6 (R = i-Bu).

The coordination chemistry of the sterically hindered macrocyclic triamines, 1,4,7-R3-1,4,7-triazacyclononane (R = i-Pr, i-Pr3tacn, and R = i-Bu, i-Bu3tacn) with divalent transition metals has been investigated. These ligands form a series of stable novel complexes with the triflate salts MII(CF3SO3)2 (M = Fe, Co, or Zn) under anaerobic conditions. The complexes Fe(i-Pr3tacn)(CF3SO3)2 (2), [Co(i-Pr3tacn)(SO3CF3)(H2O)](CF3SO3) (3), [Co(i-Pr3tacn)(CH3CN)2](BPh4)2 (4), Zn(i-Pr3tacn)(CF3SO3)2 (5), [Fe(i-Bu3tacn)(CH3CN)2(CF3SO3)](CF3SO3) (6), Fe(i-Bu3tacn)-(H2O)(CF3SO3)2 (7), and Co(i-Bu3tacn)(CF3SO3)2 (8) have been isolated. The behavior of these paramagnetic complexes in solution is explored by their 1H NMR spectra. The solid-state structures of four complexes have been determined by X-ray single-crystal crystallography. Crystallographic parameters are as follows. 2: C17H33F6FeN3O6S2, monoclinic, P2(1)/n, a = 10.895(1) A, b = 14.669(1) A, c = 16.617(1) A, beta = 101.37(1) degrees, Z = 4. 3: C17H35CoF6N3O7S2, monoclinic, P2(1)/c, a = 8.669(2) A, b = 25.538(3) A, c = 12.4349(12) A, beta = 103.132(13) degrees, Z = 4. 6: C24H45F6FeN5O6S2, monoclinic, P2(1)/c, a = 12.953(6) A, b = 16.780(6) A, c = 15.790(5) A, beta = 96.32(2) degrees, Z = 4. 7: C20H41F6FeN3O7S2, monoclinic, C2/c, a = 22.990(2) A, b = 15.768(2) A, c = 17.564(2) A, beta = 107.65(1) degrees, Z = 8. The ligand i-Pr3tacn leads to complexes in which the metal ions are five-coordinate, while it's isobutyl homologue affords six-coordinate complexes. This difference in the stereochemistries around the metal center is attributed to steric interactions involving the bulky alkyl appendages of the macrocycles.

Tetranuclear manganese carboxylate complexes with a trigonal pyramidal metal topology via controlled potential electrolysis.

Controlled potential electrolysis (CPE) procedures are described that provide access to complexes with a [Mn4(mu 3-O)3(mu 3-O2CR)]6+ core (3MnIII,MnIV) and a trigonal pyramidal metal topology, starting from species containing the [Mn4(mu 3-O)2]8+ core (4MnIII). [Mn4O2(O2CMe)6(py)2(dbm)2] (6): triclinic, P1, a = 10.868(3) A, b = 13.864(3) A, c = 10.625(3) A, alpha = 108.62(1) degrees, beta = 118.98(1) degrees, gamma = 89.34(2) degrees, V = 1307 A3, Z = 1, T = -131 degrees C, R (Rw) = 3.24 (3.70)%. [Mn4O2(O2CPh)6(py)(dbm)2] (8): monoclinic, P2(1)/c, a = 14.743(6) A, b = 15.536(8) A, c = 30.006(13) A, beta = 102.79(1) degrees, V = 6702 A3, Z = 4, T = -155 degrees C, R (Rw) = 4.32 (4.44)%. Both 6 and 8 contain a [Mn4O2]8+ core; 8 only has one py group, the fourth MnIII site being five-coordinate. (NBun4)[Mn4O2(O2CPh)7(dbm)2] (10) is available from two related procedures. CPE of 10 at 0.65 V vs ferocene in MeCN leads to precipitation of [Mn4O3(O2CPh)4(dbm)3] (11); similarly, CPE of 6 at 0.84 V in MeCN/CH2Cl2 (3:1 v/v) gives [Mn4O3(O2CMe)4(dbm)3] (12). Complex 11: monoclinic, P2(1)/n, a = 15.161(3) A, b = 21.577(4) A, c = 22.683(5) A, beta = 108.04(3) degrees, V = 7056 A3, Z = 4, T = -100 degrees C, R (wR2) = 8.63 (21.80)%. Complex 12: monoclinic, P2(1)/n, a = 13.549(2) A, b = 22.338(4) A, c = 16.618(2) A, beta = 103.74(1) degrees, V = 4885 A3, Z = 4, T = -171 degrees C, R (Rw) = 4.63 (4.45)%. Both 11 and 12 contain a [Mn4(mu 3-O)3(mu-O2CR)] core with a Mn4 trigonal pyramid (MnIV at the apex) and the RCO2- bridging the MnIII3 base. However, in 11, the carboxylate is eta 2,mu 3 with one O atom terminal to one MnIII and the other O atom bridging the other two MnIII ions, whereas in 12 the carboxylate is eta 1,mu 3, a single O atom bridging three MnIII ions. Variable-temperature, solid-state magnetic susceptibility studies on 11 and 12 show that, for both complexes, there are antiferromagnetic exchange interactions between MnIII/MnIV pairs, and ferromagnetic interactions between MnIII/MnIII pairs. In both cases, the resultant ground states of the complex is S = 9/2, confirmed by magnetization vs field studies in the 2.00-30.0 K and 0.50-50 kG temperature and field ranges, respectively.

Spin-state variation in solid state and solution of mononuclear iron(II) 1,4,7-trimethyl-1,4,7-triazacyclonane complexes.

The series of mononuclear iron(II) complexes with the tridentate macrocycle Me3tacn have been prepared (Me3tacn = 1,4,7-trimethyl-1,4,7-triazacyclonane). A purple, spin-crossover complex [Fe(Me3tacn)(MeCN)3](CF3-SO3)2 (1-OTf) forms in acetonitrile but readily loses MeCN ligands to form a colorless high-spin complex Fe(Me3tacn)(OTf)2 (2). The BPh4- salt of 1 is stable to loss of MeCN and remains purple even under a vacuum. Methylene chloride solutions of Fe(OTf)2 and Me3tacn afford crystals of [Fe(Me3tacn)(MeCN)2(OTf)](OTf) (3). Crystallization of 1-OTf in the presence of water affords a colorless high-spin complex, Fe(Me3tacn)(H2O)(CF3-SO3)2 (4), that exists as a pair of molecules bridged by hydrogen bonds between the coordinated water and the two bound triflate anions of the inversion-related partner. The crystallographic parameters are the following. 1-BPh4: C63H70B2Fe, monoclinic, P2(1)/c, a = 18.360(1) A, b = 11.761(1) A, c = 25.754(2) A, beta = 90.72(1) degrees, Z = 4. 3: C16H29Cl2F6FeN5O6S2, triclinic group P1, a = 8.500(1) A, b = 11.421(2) A, c = 15.677(2) A, alpha = 92.23(1) degrees, beta = 94.79(1) degrees, gamma = 97.03(1) degrees, Z = 2. 4: C20H18F6FeN4O6S2, monoclinic, P2(1)/n, a = 11.253(3) A, b = 12.624(5) A, c = 14.683(5) A, beta = 94.02(2) degrees, Z = 4. Variable temperature visible spectra and 1H NMR spectra of solutions of both 1-OTf and 1-BPh4 exhibit low-spin, high-spin crossover behavior, whereas 2, 3, and 4 remain high-spin in solution. The extensive role of coordinated triflate as a terminal and/or bridging ligand as well as a counteranion is demonstrated by variable temperature 19F NMR spectra.

A comparison of two skin preps used in cardiac surgical procedures.

Postoperative surgical site infections contribute significantly to increased patient morbidity and mortality rates and unnecessary hospital costs. Effective and efficient preoperative patient skin preparation is an important perioperative nursing intervention that decreases the number of wound contaminants and reduces the risks for postoperative surgical site infections. This study examined the effectiveness and time and material costs of two preoperative patient skin prep methods (ie, isopropyl alcohol prep/iodophor-impregnated adhesive drape method, iodophor scrub and paint prep/plain adhesive drape method). The isopropyl alcohol prep/iodophor-impregnated adhesive drape method clinically was as effective as the iodophor scrub and paint prep/plain adhesive drape method, more cost-effective when time and materials were compared, and less cost-effective when materials alone were compared. To make appropriate decisions about the use of preoperative patient skin prep methods, perioperative nurse managers and staff members need to examine and determine whether costs in time or materials have the greater impact on their surgical settings.