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1.
BMC Ophthalmol ; 24(1): 68, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38355425

RESUMEN

BACKGROUND: To report a case of tuberculum meningioma with recovery of glaucoma-like visual field defects after chiasmal decompression. CASE PRESENTATION: A 39-year-old woman presenting with headache was found to have bilateral arcuate retinal nerve fiber layer (RNFL) thinning on optical coherence tomography (OCT) with a corresponding arcuate scotomas consistent with glaucomatous change. However a suprasellar tumor compressing the anterior chiasm from below was found on magnetic resonance imaging of the brain. After resection of the mass, which was diagnosed as meningothelial meningioma by the pathological examination, the glaucoma-like visual field defects resolved despite the RNFL thinning on the OCT showing no improvement. CONCLUSIONS: Chiasmal compression may mimic glaucoma and produce arcuate scotoma rather than temporal visual field loss. There is a possibility that the development of chiasmal compression somehow converted preperimetric glaucoma into a more advanced form accompanied by visual field defects and that the glaucoma reverted to the preperimetric state after chiasmal decompression.


Asunto(s)
Glaucoma , Neoplasias Meníngeas , Meningioma , Femenino , Humanos , Adulto , Campos Visuales , Meningioma/complicaciones , Meningioma/diagnóstico , Meningioma/cirugía , Fibras Nerviosas/patología , Células Ganglionares de la Retina/patología , Pruebas del Campo Visual , Glaucoma/diagnóstico , Glaucoma/etiología , Glaucoma/cirugía , Escotoma/diagnóstico , Escotoma/etiología , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/etiología , Trastornos de la Visión/patología , Tomografía de Coherencia Óptica/métodos , Neoplasias Meníngeas/complicaciones , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/cirugía , Descompresión
2.
Case Rep Ophthalmol ; 13(2): 578-583, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36160483

RESUMEN

We report the case of a healthy man who was diagnosed with bilateral optic neuritis after COVID-19 vaccination. A 63-year-old man presented with acute painful blurred vision in his left eye and temporal pain. Eleven days before the appearance of his symptoms, he received the first dose of COVID-19 mRNA vaccination. On examination, his best corrected visual acuity was 20/20 in his right eye and counting fingers in the left eye. Funduscopic examination showed bilateral optic disc swelling, and postcontrast magnetic resonance imaging showed left optic nerve sheath enhancement, consistent with left optic perineuritis and right optic papillitis. After steroid pulse therapy, his visual function and headache showed significant improvement. A few cases of optic neuritis as a side effect of COVID-19 mRNA vaccination were reported. This report provides important information about side effects assumed to be related to the COVID-19 mRNA vaccine.

3.
Sci Rep ; 12(1): 16036, 2022 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-36163451

RESUMEN

This study aimed to develop a diagnostic software system to evaluate the enlarged extraocular muscles (EEM) in patients with Graves' ophthalmopathy (GO) by a deep neural network.This prospective observational study involved 371 participants (199 EEM patients with GO and 172 controls with normal extraocular muscles) whose extraocular muscles were examined with orbital coronal computed tomography. When at least one rectus muscle (right or left superior, inferior, medial, or lateral) in the patients was 4.0 mm or larger, it was classified as an EEM patient with GO. We used 222 images of the data from patients as the training data, 74 images as the validation test data, and 75 images as the test data to "train" the deep neural network to judge the thickness of the extraocular muscles on computed tomography. We then validated the performance of the network. In the test data, the area under the curve was 0.946 (95% confidence interval (CI) 0.894-0.998), and receiver operating characteristic analysis demonstrated 92.5% (95% CI 0.796-0.984) sensitivity and 88.6% (95% CI 0.733-0.968) specificity. The results suggest that the deep learning system with the deep neural network can detect EEM in patients with GO.


Asunto(s)
Oftalmopatía de Graves , Músculos Oculomotores , Oftalmopatía de Graves/diagnóstico por imagen , Humanos , Hipertrofia , Redes Neurales de la Computación , Músculos Oculomotores/diagnóstico por imagen , Estudios Prospectivos , Tomografía Computarizada por Rayos X
4.
Oper Neurosurg (Hagerstown) ; 22(3): 101-105, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35234412

RESUMEN

BACKGROUND: Few reports have shown that superior oblique myokymia (SOM) may result from vascular compression of the trochlear nerve and may be curable using microvascular decompression (MVD). OBJECTIVE: To report the clinical characteristics and surgical treatment of 2 cases of SOM and provide a review of the related literature. METHODS: Two patients with SOM were treated using MVD with the lateral supracerebellar infratentorial approach. The patients underwent diagnostic magnetic resonance imaging and three-dimensional fusion imaging preoperatively. A lateral suboccipital craniotomy was performed in the park-bench position. The trochlear nerve and branches of the superior cerebellar artery were confirmed after opening the cerebellomesencephalic fissure over the tentorial surface of the cerebellum. The vessel, which compressed the root exit zone of the trochlear nerve, was transposed far from the nerve and attached to the surface of the midbrain using Teflon felt and fibrin glue. RESULTS: The first case showed compression on both the ventral and rostral sides of the trochlear nerve root exit zone, and the second showed compression only on the ventral side. Large bridging veins on the tentorial surface of the cerebellum complicated the approach in the second case. Postoperatively, both patients had immediate and complete resolution of symptoms without recurrence at the 24-mo and 17-mo follow-ups, respectively. Five previous reports described the complete resolution of SOM after MVD. CONCLUSION: A presentation of an intermittent fluttering ocular sensation should prompt magnetic resonance imaging for ipsilateral trochlear nerve compression. The lateral supracerebellar infratentorial approach allows safe and efficacious MVD for SOM.


Asunto(s)
Cirugía para Descompresión Microvascular , Enfermedades del Nervio Troclear , Humanos , Enfermedades del Nervio Troclear/diagnóstico por imagen , Enfermedades del Nervio Troclear/cirugía , Imagen por Resonancia Magnética , Craneotomía/métodos , Mesencéfalo/diagnóstico por imagen , Mesencéfalo/cirugía
5.
Am J Ophthalmol Case Rep ; 25: 101368, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35146212

RESUMEN

PURPOSE: To report a case of unilateral petrous apex cephalocele (PAC) and contralateral vitreous hemorrhage in a young patient with intracranial hypertension. OBSERVATIONS: A 12-year-old boy had acute visual loss in the right eye. The clinical and radiological findings were consistent with right vitreous hemorrhage with mild intracranial hypertension and left PAC. Cerebral angiography demonstrated low flow of the left inferior petrosal sinus and anterior venous high flow from the cavernous sinus to the facial vein via the superior ophthalmic vein. The presence of an expanding PAC, blocking the venous flow away from the inferior petrosal sinus, would produce an ipsilateral intraocular pressure (IOP) (20 mmHg) mildly higher than the other one (16 mmHg) although it is in the normal range, which may have caused the difference of the translaminar pressure gradient resulting from the balance between the cerebrospinal flow pressure and the IOP. CONCLUSION AND IMPORTANCE: Unilateral expanding PAC may cause intracranial hypertension with different severity of papilledema between two eyes.

6.
Case Rep Ophthalmol ; 13(3): 730-735, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36845459

RESUMEN

The characteristics of hemorrhagic macular cysts (HMCs) in patients with Terson's syndrome, focusing on the vitreoretinal interface observed through an ophthalmic surgical microscope, are described. Between May 2015 and February 2022, 19 eyes (17 patients) with vitreous hemorrhage (VH) occurring after subarachnoid hemorrhage underwent pars plana vitrectomy. After removing dense VH, 2 of 19 eyes had HMCs. In both cases with HMCs, they formed a dome-like shape and were located beneath the internal limiting membrane (ILM), lying beyond the clean posterior precortical vitreous pocket (PPVP) without hemorrhage despite the severe VH. Based on the microsurgical findings, it appears that two types of HMCs consisting of subhyaloid and sub-ILM hemorrhages in Terson's syndrome may be involved in the impairment of adhesion of the posterior border of the PPVP and the ILM surface of the macula due to micro bleeding, and that the PPVP may prevent the sub-ILM type of HMC from breaking into the subhyaloid space and transforming into the subhyaloid type. In conclusion, the PPVP may play an important role in the formation of HMCs in Terson's syndrome.

7.
Am J Ophthalmol Case Rep ; 20: 100929, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33005817

RESUMEN

PURPOSE: To report a case of congenital geniculate quadruple sectoranopia associated with occipital heterotopia. OBSERVATIONS: A 51-year-old healthy woman was incidentally found to have a left incongruous quadruple sectoranopia. Analysis of the macular ganglion cell complex (GCC) revealed homonymous hemianopic thinning of the inner layer of the retina. Brain magnetic resonance imaging (MRI) showed congenital occipital heterotopia, characterized by hypertrophy of the right parahippocampal gyrus, lingual gyrus, and isthmus of the cingulate gyrus, with shrinkage of the white matter. In addition, serial coronal images on a short tau inversion recovery (STIR) sequence demonstrated an atrophic right optic tract. CONCLUSION AND IMPORTANCE: Congenital geniculate quadruple sectoranopia is extremely rare and may be caused by congenital occipital heterotopia.

8.
Am J Ophthalmol Case Rep ; 17: 100613, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32083223

RESUMEN

PURPOSE: To describe features characteristic of vitreous hemorrhage in patients with Terson syndrome observed through a microsurgical scope. METHODS: Between May 2015 and February 2019, 12 eyes of 10 patients with vitreous hemorrhage occurring after subarachnoid hemorrhage (SAH) underwent pars plana vitrectomy. RESULTS: During vitreous surgery, we found 10 of 12 eyes did not have posterior vitreous detachment (PVD). Furthermore, we observed in 9 of the 10 eyes without PVD (90.0%) that there was no hemorrhage in the posterior vitreous cavity at the posterior pole while we removed vitreous hemorrhage. We confirmed that this clean space could be the posterior precortical vitreous pocket (PPVP). CONCLUSION AND IMPORTANCE: Terson syndrome may have no hemorrhage in the PPVP regardless of the presence of severe vitreous hemorrhage. The cases presented in our study may suggest one of the mechanisms of Terson syndrome.

9.
Orbit ; 37(3): 165-170, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29023217

RESUMEN

We demonstrate a case of ocular impairment caused by a hydroxyapatite filler injection and review the prior literature on clinical presentations. A healthy woman, who received a hydroxyapatite filler injection into the glabella for nose augmentation suddenly had symptoms of nausea, diplopia, visual loss in the left eye, and impaired consciousness. Her left eye showed paresis of the inferior branch of the oculomotor nerve, conjunctival injection, cell infiltration in the anterior chamber, and multiple white spots in the nasal fundus. Purpura was detected in the area from the glabella to the left forehead. An orbital computed tomography (CT) scan demonstrated high-density deposits along vessels in the left medial orbit and forehead. Although her consciousness stabilized after a few days, the vision in her left eye deteriorated due to corneal edema and both hypopyon and hyphema in the anterior chamber, and the skin from the glabella to the left forehead developed necrosis. Multiple plaques were observed within the conjunctival and scleral vessels. After 2 months, diplopia and visual loss issues were mostly resolved. A histological examination of the conjunctiva specimen showed multiple foreign bodies plugged vessels that could be dissolved by decalcification. Recently, the number of complications by cosmetic filler injections has increased. The migrated hydroxyapatite particles in vessels cause multiple vascular emboli that can lead to various symptoms.


Asunto(s)
Arteriopatías Oclusivas/etiología , Materiales Biocompatibles/efectos adversos , Durapatita/efectos adversos , Embolia/etiología , Arteria Oftálmica , Trastornos de la Visión/etiología , Adulto , Arteriopatías Oclusivas/diagnóstico por imagen , Conjuntiva/irrigación sanguínea , Técnicas Cosméticas , Embolia/diagnóstico por imagen , Femenino , Humanos , Angiografía por Resonancia Magnética , Rinoplastia , Esclerótica/irrigación sanguínea , Tomografía Computarizada por Rayos X , Trastornos de la Visión/diagnóstico , Personas con Daño Visual
10.
Eur Radiol ; 26(8): 2640-5, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26607576

RESUMEN

OBJECTIVES: To evaluate the usefulness of the signal intensity ratio (SIR) of the optic nerve to the white matter (WM) on short tau inversion recovery (STIR) images to diagnose acute optic neuritis (AON). METHODS: The 405 consecutive patients with suspected orbital diseases underwent orbital magnetic resonance imaging (MRI) using a 3-T scanner between June 2008 and August 2011. Among them, 108 optic nerves (33 AON and 75 control) were retrospectively analysed. The averaged SIR (SIRave) and maximum SIR (SIRmax) were defined as the averaged signal intensity (SI) of the optic nerve divided by that of WM, and the maximum SI of the optic nerve divided by averaged SI of WM, respectively. These values were compared between AON and control using the Mann-Whitney U test. A P < 0.05 was considered statistically significant. RESULTS: SIRave and SIRmax were significantly (P < 0.001) higher in the AON compared to the control. At a cut-off SIRave value of 1.119, the sensitivity, specificity and accuracy were 0.939, 0.840, and 0.870; and at a cut-off SIRmax value of 1.281, these were 1.000, 0.720 and 0.806, respectively. CONCLUSION: The SIR of the optic nerve to WM on STIR images is of value in diagnosing AON. KEY POINTS: • We propose a method of diagnosing acute optic neuritis using 3-T MRI. • Our method is simple and objective and requires no novel imaging techniques. • Our method shows high diagnostic accuracy.


Asunto(s)
Lóbulo Frontal/diagnóstico por imagen , Nervio Óptico/diagnóstico por imagen , Neuritis Óptica/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto Joven
11.
Dalton Trans ; 44(44): 19056-8, 2015 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-26447328

RESUMEN

A polyoxometalate-silver ethynide composite cluster, [Ag42(CO3){C≡CC(CH3)3}27(α-A-SiW9Nb3O40)2](-) (1), demonstrates that we can select the binding site of a polyoxometalate to the silver alkynide cluster by tuning the surface charge of the precursor polyoxometalate. Multidimensional and multinuclear NMR spectra revealed that 1 maintains its precise atomic connectivity in the solution.

12.
Case Rep Ophthalmol ; 6(2): 149-57, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26078748

RESUMEN

In the present study, two female patients with unilateral scleritis without systemic complications were examined. Both patients were suffering from ocular pain and received corticosteroid therapy. The first patient, a 45-year-old woman, was diagnosed with scleritis and iritis in her right eye. Topical corticosteroid treatment could eradicate the iritis but not the scleritis. Oral corticosteroid administration and corticosteroid pulse therapy were applied with little effect. The application of systemic cyclosporine had a satisfactory effect in controlling the scleritis. The other patient, a 60-year-old woman, was suffering from scleritis and lid swelling in her right eye. Not only did topical and systemic corticosteroid therapy prove insufficient, they also resulted in the elevation of her intraocular pressure. After termination of corticosteroid therapy, the systemic cyclosporine was applied orally. Subsequently, the patient's scleritis improved without any severe side effects. Scleritis is a painful and destructive inflammatory disease of the sclera that causes congestion of the scleral venous plexus. In this study, we have established a new grading system for assessing activity in scleritis that can score the extent of ocular pain and the area of congestion. This system provides a practical method for following the clinical course and monitoring the outcome of therapy. We report two cases of unilateral scleritis that were resistant to corticosteroid therapy but responsive to systemic administration of cyclosporine. Findings from these cases indicate that cyclosporine is an effective drug for controlling severe scleritis.

13.
Pestic Biochem Physiol ; 119: 1-8, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25868810

RESUMEN

Biotypes of Echinochloa crus-galli var. formosensis with resistance to cyhalofop-butyl, an acetyl-CoA carboxylase (ACCase) inhibitor, have been found in dry-seeded rice fields in Okayama, Japan. We collected two lines with suspected resistance (Ecf27 and Ecf108) from dry-seeded rice fields and investigated their sensitivity to cyhalofop-butyl and other herbicides. Both lines exhibited approximately 7-fold higher resistance to cyhalofop-butyl than a susceptible line. Ecf108 was susceptible to penoxsulam, an acetolactate synthase (ALS) inhibitor. On the other hand, Ecf27 showed resistance to penoxsulam and two other ALS inhibitors: propyrisulfuron and pyriminobac-methyl. The alternative herbicides butachlor, thiobencarb, and bispyribac-sodium effectively controlled both lines. To examine the molecular mechanisms of resistance, we amplified and sequenced the target-site encoding genes in Ecf27, Ecf108, and susceptible lines. Partial sequences of six ACCase genes and full-length sequences of three ALS genes were examined. One of the ACCase gene sequences encodes a truncated aberrant protein due to a frameshift mutation in both lines. Comparisons of the genes among Ecf27, Ecf108, and the susceptible lines revealed that none of the ACCases and ALSs in Ecf27 and Ecf108 have amino acid substitutions that are known to confer herbicide resistance, although a single amino acid substitution was found in each of three ACCases in Ecf108. Our study reveals the existence of a multiple-herbicide resistant biotype of E. crus-galli var. formosensis at Okayama, Japan that shows resistance to cyhalofop-butyl and several ALS inhibitors. We also found a biotype that is resistant only to cyhalofop-butyl among the tested herbicides. The resistance mechanisms are likely to be non-target-site based, at least in the multiple-herbicide resistant biotype.


Asunto(s)
Butanos/farmacología , Echinochloa/efectos de los fármacos , Resistencia a los Herbicidas , Herbicidas/farmacología , Nitrilos/farmacología , Oryza/crecimiento & desarrollo , Malezas/efectos de los fármacos , Semillas/crecimiento & desarrollo , Acetolactato Sintasa/genética , Acetolactato Sintasa/metabolismo , Acetil-CoA Carboxilasa/genética , Acetil-CoA Carboxilasa/metabolismo , Echinochloa/enzimología , Echinochloa/genética , Oryza/enzimología , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Malezas/enzimología , Malezas/genética , Semillas/enzimología , Semillas/genética
14.
Mod Rheumatol ; 25(2): 199-204, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25159154

RESUMEN

Abstract Objective. Immunoglobulin (Ig)G4-related disease (IgG4-RD) is a new disease entity that has only been identified this century. Clinical information is thus lacking. We established the Sapporo Medical University and Related Institutes Database for Investigation and Best Treatments of IgG4-related Disease (SMART) to clarify the clinical features of IgG4-RD and provide useful information for clinicians. Methods. Participants comprised 122 patients with IgG4-related dacryoadenitis and/or sialadenitis (IgG4-DS), representing lacrimal and/or salivary lesions of IgG4-RD, followed-up in December 2013. We analyzed the sex ratio, mean age at onset, organ dysfunction, history or complications of malignancy, treatments, rate of clinical remission, and relapse. Results. The sex ratio was roughly equal. Mean age at diagnosis was 59.0 years. Positron emission tomography revealed that the ratio of other organ involvements was 61.4%. Complications of malignancy were observed in 7.4% of cases. Glucocorticoid was used to treat 92.1% of cases, and the mean maintenance dose of prednisolone was 4.8 mg/day. Rituximab was added in three cases, and showed good steroid-sparing effect. The clinical remission rate was 73.8%, and the annual relapse rate was 11.5%. Half of the cases experienced relapses within 7 years of initial treatment. Conclusion. We analyzed the clinical features and treatments of IgG4-DS using SMART, providing useful information for everyday clinical practice.


Asunto(s)
Enfermedades Autoinmunes/diagnóstico , Dacriocistitis/diagnóstico , Inmunoglobulina G , Inmunosupresores/uso terapéutico , Sialadenitis/diagnóstico , Adulto , Edad de Inicio , Anciano , Anciano de 80 o más Años , Enfermedades Autoinmunes/tratamiento farmacológico , Dacriocistitis/tratamiento farmacológico , Bases de Datos Factuales , Femenino , Glucocorticoides/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Prednisolona/uso terapéutico , Sialadenitis/tratamiento farmacológico , Resultado del Tratamiento , Adulto Joven
15.
J Neuroophthalmol ; 34(4): 393-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25405661

RESUMEN

Immunoglobulin (Ig) G4-related disease (IgG4-RD) is a chronic inflammatory disorder characterized by elevated serum level of IgG4 and abundant infiltration of IgG4-bearing plasmacytes and fibrosis in various organs, typically including the lacrimal glands, salivary glands, pancreas, thyroid gland, lungs, and kidneys. Lacrimal and orbital involvements are called IgG4-related ophthalmic disease, often presenting as orbital myositis, perineuritis of the optic and trigeminal nerves, and orbital inflammation. In particular, a characteristic finding is infraorbital nerve enlargement on magnetic resonance imaging. Systemic screening is necessary to establish the diagnosis of IgG4-RD, and it must be distinguished from neoplastic disease. Corticosteroid treatment is effective in inducing remission but some patients may relapse during tapering of pharmacotherapy. This review encompasses the history, clinical profile, diagnostic criteria, treatment, and prognosis of IgG4-RD.


Asunto(s)
Enfermedades Autoinmunes/sangre , Enfermedades Autoinmunes/inmunología , Inmunoglobulina G/sangre , Corticoesteroides/uso terapéutico , Enfermedades Autoinmunes/tratamiento farmacológico , Conductos Biliares/patología , Humanos , Páncreas/patología , Glándulas Salivales/patología
16.
Dalton Trans ; 43(2): 402-5, 2014 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-24212334

RESUMEN

A novel aquachloridooxidodiperoxidomolybdate(vi), [MoClO(O2)2(OH2)](-), was crystallised as tetraethylammonium and triethylmethylammonium salts from strongly acidic aqueous solutions, and was structurally analysed by single crystal X-ray diffraction and NMR spectroscopy. The aqueous behaviour of the present anion observed by (17)O NMR agrees with that reported in a previous speciation study.

17.
Acta Crystallogr C ; 69(Pt 12): 1494-7, 2013 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-24311498

RESUMEN

The title salts calcium (glycinato-κ(2)N,O)oxidobis(peroxido-κ(2)O,O')vanadate(V) tetrahydrate, Ca[VO(O2)2(NH2CH2COO)]·4H2O, and strontium (glycinato-κ(2)N,O)oxidobis(peroxido-κ(2)O,O')vanadate(V) tetrahydrate, Sr[VO(O2)2(NH2CH2COO)]·4H2O, crystallized at pH ca 7.4 with similar lattice parameters. The glycinate anion acts as a bidentate N,O-chelating ligand, and the V atom has a pentagonal bipyramidal geometry, with two η(2)-peroxo groups and the glycinate N atom in the equatorial plane, and one terminal oxo and a glycinate O atom at the axial positions. The H atoms of three of the four water molecules in the strontium salt exhibited disorder over three positions for each molecule.


Asunto(s)
Calcio/química , Complejos de Coordinación/química , Sales (Química)/química , Estroncio/química , Cristalografía por Rayos X , Enlace de Hidrógeno , Concentración de Iones de Hidrógeno , Estructura Molecular
18.
Acta Crystallogr C ; 69(Pt 1): 37-40, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23282910

RESUMEN

The unit-cell parameters of the three title salts, namely, tripotassium, K(3)[Mo(2)(CHO(2))O(3)(O(2))(4)], trirubidium, Rb(3)[Mo(2)(CHO(2))O(3)(O(2))(4)], and triammonium µ-(formato-κ(2)O:O')-µ-oxido-bis[oxidobis(peroxido-κ(2)O,O')molybdate(VI)], (NH(4))(3)[Mo(2)(CHO(2))O(3)(O(2))(4)], which were all crystallized at pH 3, are quite similar, but the potassium and rubidium salt structures are noncentrosymmetric, whereas that of the ammonium salt is centrosymmetric. Formate acts as an O:O'-bridging ligand in the complex anion and is bound to a µ-oxido-bis(oxidodiperoxidomolybdate) unit.

19.
Dalton Trans ; 41(25): 7485-97, 2012 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-22584428

RESUMEN

Magnitudes of the p(Z)-π(Ar/Nap) conjugation were evaluated for 1-(arylchalcogena)naphthalenes (1-(ArZ)Nap, 1-(p-YC(6)H(4)Z)C(10)H(7); 1 (Z = Te), 2 (Se), 3 (S) and 4 (O)). Structures of 1 were determined by X-ray analysis for Y = NMe(2) (b), OMe (c) and CN (i). For 1b and 1c that have electron donating Y, the Z-C(Ar) bond is located on the naphthyl plane with Z-C(Nap) being perpendicular to the aryl plane, which we define as (B: pd). On the other hand, the structure of 1i with electron donating Y is (A: pl), of which Z-C(Ar) is placed almost perpendicular to the naphthyl plane with Z-C(Nap) being located on the aryl plane. Each structure of 1a (Y = H), 1b, 1c, 1d (Me), 1e (F), 1f (Cl), 1g (Br), 1h (COOEt), 1i and 1j (NO(2)) was determined by NMR in chloroform-d. Structures of 1 in the solutions are (B: pd) for b, c and e that have electron donating Y, (A: pl) for f-j with electron accepting Y, and in equilibrium between (B: pd) and (A: pl) for a and d of which Y are rather neutral. The results for 2-4 are very similar to those of 1 in solutions. Quantum chemical calculations were performed on 1-4 with Y of a, b' (NH(2)), d, f and j. Magnitudes of the p(Z)-π(Ar/Nap) conjugation were well-evaluated by NBO (natural bond orbital) analysis. The values were 12.6 and 13.0 kcal mol(-1) for the typical forms of (A: pl) and (B: pd) of 1a, respectively, resulting in a much smaller energy difference between the two (0.4 kcal mol(-1)), which should correspond to the observed result. It is well-demonstrated that the p(Te)-π(Ar/Nap) conjugation operates effectively in 1, although the magnitudes increase in the order of Z = Te < Se < S < O. Thermal effect of the Gibbs free energies is shown to play an important role in the energy profiles of 1a-4a.

20.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 12): m1467, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23468694

RESUMEN

A trimethyl-phenyl-ammonium salt of a dinuclear µ-oxalate complex of diperoxidomonomolybdate units, (C9H14N)2[Mo2(C2O4)(O2)4O2], was obtained from an acidic aqueous solution; the dianion is located about a centre of inversion. Each Mo atom bears two peroxide groups together with one O atom from the oxalate group in its equatorial positions and one terminal O atom as well as another O atom from the oxalate in axial positions. The oxalate group acts as a tetra-dentate bridging ligand and bridges between the diperoxidomolybdate units.

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