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1.
HSS J ; 18(3): 393-398, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35846269

RESUMO

Background: Decreased length of stay after total joint arthroplasty (TJA) is becoming a more common way to contain healthcare costs and increase patient satisfaction. There is little evidence to support "early" discharge in elderly patients. Purpose: We sought to identify preoperative factors that correlated with early discharge (by postoperative day [POD] 1) in comparison to late discharge (after POD2) in octogenarians after TJA. Methods: In a retrospective cohort study from a single institution, we identified 482 patients ages 80 to 89 who underwent primary TJA from January 2014 to December 2017; 319 had total knee arthroplasty (TKA) and 163 had total hip arthroplasty (THA). Data collected included preoperative knee range of motion (ROM), demographics, and comorbidities; 90-day readmission and mortality rates were also evaluated. P values for continuous data were calculated using student's t test and for categorical data using χ2 testing. Results: Of octogenarian patients, 30.9% were discharged by POD1. Early discharge was associated with being male, married, and nonsmoking, as well as having an American Society of Anesthesiologists (ASA) score of 2, independent preoperative ambulation, and a postoperative caregiver. Type of procedure (TKA vs THA), body mass index, laterality, preoperative range of motion (ROM) for TKA, and single vs multilevel home did not affect the probability of early discharge. Discharge on POD1 was not associated with increased 90-day readmission rates. There were no deaths. Conclusion: Early discharge for octogenarians can be successfully implemented in a select subset of patients without increasing 90-day readmission or death rates. There are multiple factors that predict successful early discharge.

2.
J Arthroplasty ; 36(9): 3269-3274, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34053749

RESUMO

BACKGROUND: In revision total hip arthroplasty (THA) cases with preserved femoral metaphyseal bone, tapered proximally porous-coated "primary" femoral stems may be an option. The objective of this study was to compare outcomes of patients with Paprosky I or II femoral bone loss undergoing revision THA with either a primary metaphyseal-engaging cementless stem or a revision diaphyseal-engaging stem. METHODS: This was a retrospective analysis of 70 patients with Paprosky I or II femoral bone loss who underwent femoral revision. 35 patients who were revised using a primary cementless femoral stem were compared with 35 patients who underwent femoral revision using a revision diaphyseal-engaging stem. The groups were similar regarding age, gender, body mass index, and American Society of Anesthesiologists. Clinical and radiographic outcomes and complications were compared over an average follow-up of 2.9 years (SD 1.4). RESULTS: Revision THA was most commonly performed for periprosthetic joint infection (N = 27, 38.6%). The groups were similar with regards to Paprosky femoral classification (P = .56), length of stay (P = .68), discharge disposition (P = .461), operative time (P = .20), and complications (P = .164). There were no significant differences between primary and revision femoral stem subsidence (0.12 vs. 0.75 mm, P = .18), leg length discrepancy (2.3 vs. 4.05 mm, P = .37), and Hip Disability and Osteoarthritis Outcome Score Jr (73.1 [SD 21.1] vs. 62.8 [SD 21.7], P = .088). No patient underwent additional revision surgery involving the femoral component. CONCLUSION: Use of modern primary cementless femoral stems is a viable option for revision hip arthroplasty in the setting of preserved proximal femoral metaphyseal bone. Outcomes are not inferior to those of revision stems and offer potential benefits.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Prótese de Quadril/efeitos adversos , Humanos , Desenho de Prótese , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
3.
BMC Musculoskelet Disord ; 22(1): 478, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34030681

RESUMO

BACKGROUND: Dislocation after primary total hip arthroplasty (THA) has an incidence of 2-3%. Approximately 77% of dislocations occur within the first year after surgery. The SuperPATH technique is a minimally invasive approach for THA that preserves soft tissue attachments. The purpose of this study is to describe the dislocation rate at 1 year after SuperPATH primary THA. METHODS: All elective primary THAs performed by the senior author using the SuperPATH approach. Exclusion criteria were acute femoral neck fracture, revision surgery, or malignancy. There were 214 of 279 eligible patients available for telephone interviews (76.7%). Medical records were reviewed for secondary outcomes including early and late complications, cup positioning, distance ambulated on postoperative day one, discharge destination, and blood transfusions. RESULTS: Mean age at surgery was 64 ± 10.8 years and mean time to telephone follow up was 773 ± 269.7 days. There were 104 female and 110 male patients. There were zero dislocations reported. Blood transfusions were performed in 3.7% of patients, and 75.7% were discharged to home at an average of 2.3 ± 1.0 days. Cup position averaged 43.6 ± 5.2° abduction and 20.9 ± 6.2° anteversion, with an average leg length discrepancy of 3.6 ± 3.32 mm. Complications included three intraoperative calcar fractures, one periprosthetic femur fracture, one early femoral revision, three superficial infections, and one instance of wound necrosis. CONCLUSION: SuperPATH approach is safe for use in primary THA resulting in a low dislocation rate.


Assuntos
Artroplastia de Quadril , Fraturas do Colo Femoral , Prótese de Quadril , Luxações Articulares , Artroplastia de Quadril/efeitos adversos , Feminino , Fraturas do Colo Femoral/diagnóstico por imagem , Fraturas do Colo Femoral/epidemiologia , Fraturas do Colo Femoral/cirurgia , Fêmur , Seguimentos , Prótese de Quadril/efeitos adversos , Humanos , Masculino , Estudos Retrospectivos
4.
Insights Imaging ; 11(1): 84, 2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32681296

RESUMO

MRI has a vital role in the assessment of intracranial lesions. Conventional MRI has limited specificity and multiparametric MRI using diffusion-weighted imaging, perfusion-weighted imaging and magnetic resonance spectroscopy allows more accurate assessment of the tissue microenvironment. The purpose of this educational pictorial review is to demonstrate the role of multiparametric MRI for diagnosis, treatment planning and for assessing treatment response, as well as providing a practical approach for performing and interpreting multiparametric MRI in the clinical setting. A variety of cases are presented to demonstrate how multiparametric MRI can help differentiate neoplastic from non-neoplastic lesions compared to conventional MRI alone.

5.
J Am Acad Orthop Surg ; 28(6): e255-e262, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31206437

RESUMO

INTRODUCTION: Perioperative hypothermia (PH) is common in patients undergoing total joint arthroplasty (TJA). A previous study at our institution identified the largest drop in core body temperature between preoperative holding and induction of anesthesia. This study evaluates the effect of preoperative warming measures on PH in TJA patients. METHODS: A retrospective review was conducted of 672 patients undergoing TJA at our institution between April 1 and October 31, 2017. Under the new normothermia protocol, patients received warmed intravenous fluids and forced-air warming gowns in the preoperative holding area. Time and temperature data for the perioperative period were collected from the electronic health record. Chi-square and paired t-tests were used to compare between total knee arthroplasty and total hip arthroplasty patients and between new and old protocols. RESULTS: In the new protocol, 173 of 672 (26%) patients were hypothermic at incision compared with 140 of 383 (37%) patients in the previous protocol (P < 0.05). The largest drop in core body temperature occurred between preoperative holding and induction of anesthesia. The duration of time from operating room entry to incision was less for normothermic than for hypothermic patients. The duration of hypothermia was similar between new and old protocols overall, but markedly fewer total hip arthroplasty patients remained hypothermic for the entire surgery under the new protocol. CONCLUSION: Adding forced-air warming preoperatively to our warming protocol reduced the rate of PH by approximately 30%. The time from entry into the operating room to the start of surgery should be minimized because patients are vulnerable to PH during this interval.


Assuntos
Artroplastia de Quadril , Artroplastia do Joelho , Regulação da Temperatura Corporal , Hipotermia/prevenção & controle , Complicações Intraoperatórias/prevenção & controle , Reaquecimento , Adulto , Humanos , Período Perioperatório , Estudos Retrospectivos
6.
Arthroplast Today ; 5(2): 193-196, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31286043

RESUMO

BACKGROUND: Total hip arthroplasty (THA) is the preferred treatment for displaced femoral neck fractures in select patients, although dislocation remains a concern. In some studies, the supercapsular percutaneously assisted (SuperPATH) approach has demonstrated early mobilization, short hospital stay, and low dislocation rates in primary THA, but there are little data on its use for fractures. This study describes the perioperative outcomes and early dislocation rate of SuperPATH THA for displaced femoral neck fragility fractures. METHODS: A retrospective review was performed of previous ambulatory patients with a displaced femoral neck fragility fracture treated with THA using the SuperPATH approach. Demographic data, time to ambulation, length of stay, and in-hospital complications during the hospital stay and follow-up period were recorded. Phone interviews were conducted to check for dislocations 1 year after surgery. RESULTS: Thirty-seven consecutive patients were included with an average age of 75.0 years. Hospital stay averaged 5.5 days, and patients were discharged on average postoperative day 3.6. About 83.8% of patients were ambulatory by postoperative day 1, and 94.6% ambulatory before discharge. Twenty-seven percent of patients were discharged home, 46% to inpatient rehabilitation, 24% to skilled nursing facility, and 1 patient to hospice. At follow-up, there was no symptomatic heterotopic ossification and no infections. Thirty-two patients were available for telephone interviews at 1 year, with no dislocations reported. CONCLUSIONS: In this small cohort, the SuperPATH approach for THA appears to be safe and effective for use in femoral neck fragility fractures, resulting in early ambulation and a low dislocation rate.

8.
Orthopedics ; 41(2): e252-e256, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29451935

RESUMO

Ankle fractures are among the most common injuries requiring operative management. Implant choices include one-third tubular plates and anatomically precontoured plates. Although cadaveric studies have not revealed biomechanical differences between various plate constructs, there are substantial cost differences. This study sought to characterize the economic implications of implant choice. A retrospective review was undertaken of 201 consecutive patients with operatively treated OTA type 44B and 44C ankles. A Nationwide Inpatient Sample query was performed to estimate the incidence of ankle fractures requiring fibular plating, and a Monte Carlo simulation was conducted with the estimated at-risk US population for associated plate-specific costs. The authors estimated an annual incidence of operatively treated ankle fractures in the United States of 59,029. The average cost was $90.86 (95% confidence interval, $90.84-$90.87) for a one-third tubular plate vs $746.97 (95% confidence interval, $746.55-$747.39) for an anatomic plate. Across the United States, use of only one-third tubular plating over anatomic plating would result in statistically significant savings of $38,729,517 (95% confidence interval, $38,704,773-$38,754,261; P<.0001). General use of one-third tubular plating instead of anatomic plating whenever possible for fibula fractures could result in cost savings of up to nearly $40 million annually in the United States. Unless clinically justifiable on a per-case basis, or until the advent of studies showing substantial clinical benefit, there currently is no reason for the increased expense from widespread use of anatomic plating for fractures amenable to one-third tubular plating. [Orthopedics. 2018; 41(2):e252-e256.].


Assuntos
Fraturas do Tornozelo/cirurgia , Placas Ósseas/economia , Fíbula/cirurgia , Fixação Interna de Fraturas/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Adolescente , Adulto , Fraturas do Tornozelo/economia , Redução de Custos , Feminino , Fíbula/lesões , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Texas , Adulto Jovem
9.
Instr Course Lect ; 67: 567-578, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31411440

RESUMO

The management of metastatic spine disease has evolved substantially in the past 5 years. Early treatment approaches with more aggressive surgical indications were based on studies that misinterpreted or overemphasized the advantages of the surgical management of metastatic spine disease. However, substantial advantages in radiation therapy, chemotherapy, and biologic agents have led to considerable improvements in patient outcomes and have, in many patients, shifted the paradigm back to nonsurgical or less invasive treatment modalities. Surgeons should be aware of critiques of earlier treatment strategies and associated frameworks for the management of metastatic spine disease. The Medical, Oncologic, Stenosis, and Stability framework was developed to address some of the shortcomings of early metastatic spine disease treatment approaches.

10.
World Neurosurg ; 107: 445-450, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28790004

RESUMO

BACKGROUND: Cervical spondylotic myelopathy (CSM) is a disorder that can cause neurologic deterioration. Studies on paraspinal muscular atrophy (PMA) in the lumbar spine have shown that these changes are caused by several perioperative factors. It is possible that PMA in the cervical spine could behave similarly. In this retrospective study, we compared the degree of PMA after laminoplasty versus laminectomy and fusion (LF) using a standard posterior approach to the cervical spine. METHODS: 18 laminoplasty and 43 LF patients were included in this study. For each patient, preoperative and postoperative MRI files were obtained and transferred into OsiriX imaging software. Atrophy rate was obtained and reported as percentage change in cross-sectional area of the cervical paraspinal muscles from preoperative to postoperative imaging. RESULTS: Mean cross-sectional cervical muscle atrophy rates were 6% and 13.1% for laminoplasty and LF, respectively, representing a 2.19 times increase in the degree of atrophy (P < 0.001). Independently, LF was associated with a 5.84% increase in the rate of PMA (P = 0.03). Involvement of C3 as the cephalad surgical level was associated with a 5.78% decrease in the rate of PMA (P = 0.03). For each degree increase in postoperative Cobb angle, there was a 0.66% decrease in the rate of PMA (P = 0.02). CONCLUSION: PMA should be part of the decision making process when a posterior approach is considered, inasmuch as this study demonstrates that cervical laminoplasty was associated with significantly lower rates of PMA compared with cervical laminectomy and fusion. Additionally, these results suggest that minimizing PMA may help preserve cervical lordosis.


Assuntos
Laminectomia/tendências , Laminoplastia/tendências , Atrofia Muscular/diagnóstico por imagem , Doenças da Medula Espinal/diagnóstico por imagem , Fusão Vertebral/tendências , Espondilose/diagnóstico por imagem , Idoso , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Feminino , Humanos , Laminectomia/efeitos adversos , Laminoplastia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Atrofia Muscular/etiologia , Músculos Paraespinais/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Doenças da Medula Espinal/cirurgia , Fusão Vertebral/efeitos adversos , Espondilose/cirurgia , Resultado do Tratamento
11.
Appl Opt ; 56(10): 2630-2635, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28375222

RESUMO

The reductions in the transmission of emission originating from a fluorophore dissolved in a polymer matrix due to light scattering were compared in two forms of planar waveguides used as luminescent solar concentrators: a thin film of poly(methylmethacrylate) (PMMA) spin-coated on a glass plate and a solid PMMA plate of the same dimensions. The losses attributable to light scattering encountered in the waveguide consisting of the thin film of polymer coated on a glass plate were not detectable within experimental uncertainty, whereas the losses in the solid polymer plate were significant. The losses in the solid plate are interpreted as arising from light-scattering centers comprising minute bubbles of vapor/gas, incomplete polymerization or water clusters that are introduced during or after the thermally induced polymerization process.

12.
J Orthop Trauma ; 31(4): 236-240, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27984442

RESUMO

OBJECTIVES: To determine the proportion of patients requiring secondary surgery for symptomatic implant removal after open reduction, internal fixation using dual mini-fragment plating technique for clavicular shaft fractures. DESIGN: Retrospective observational study. SETTING: Single university Level 1 trauma center. PATIENTS: Eighty-one patients treated with open reduction, internal fixation using dual mini-fragment plating technique for clavicular shaft fractures (OTA/AO 15-B1, B2, and B3) with minimum 12-month follow-up (median 477 days; range 371-1549 days). INTERVENTION: Open reduction, internal fixation using dual mini-fragment plating technique for clavicular shaft fractures. MAIN OUTCOME MEASUREMENTS: Incidence of secondary surgery, QuickDASH (Disabilities of the Arm, Shoulder, and Hand) scores. RESULTS: Six of 81 patients (7.4%) underwent secondary surgery for implant removal for any reason. Of these, 3 (3.7%) underwent symptomatic implant (soft-tissue irritation) removal, 2 (2.5%) required implant removal in the setting of infection, and 1 patient (1.2%) required revision open reduction internal fixation for early implant failure. The mean QuickDASH score in this series was 8.44 (±6.94, range 0-77.27). The associated implant cost of the typical construct utilized in this series was $1511.38. The mean surgical time was 97 minutes (range 71-143 minutes). CONCLUSIONS: The utilization of a dual mini-fragment plating technique in the treatment of clavicular shaft fractures results in a low rates of secondary surgery for symptomatic implant removal (3.7%) and similar QuickDASH scores when compared with historical controls treated with 3.5-mm plates placed on the superior clavicle. Potential disadvantages in using this technique include a higher surgical implant cost and length of surgery. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Clavícula/lesões , Remoção de Dispositivo/estatística & dados numéricos , Fixação Interna de Fraturas/instrumentação , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Adolescente , Adulto , Distribuição por Idade , Idoso , Placas Ósseas/estatística & dados numéricos , Clavícula/cirurgia , Comorbidade , Análise de Falha de Equipamento , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/estatística & dados numéricos , Humanos , Incidência , Pessoa de Meia-Idade , Miniaturização , Desenho de Prótese , Falha de Prótese , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Avaliação de Sintomas , Texas/epidemiologia , Resultado do Tratamento , Adulto Jovem
13.
Photochem Photobiol Sci ; 15(9): 1163-1169, 2016 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-27480331

RESUMO

The fluorescence spectra, quantum yields and lifetimes of a series of alkoxy-substituted phenylenevinylene molecules, which serve as short chain oligomer models for poly(p-phenylenevinylene), have been determined in fluid solvents and in a high viscosity polymer matrix. The effects of solvent polarity and a high viscosity molecular environment on the fluorescence yields and spectral shapes have been established. Alkoxy group substitution on the phenyl ring moieties of the molecules has an important effect on the vibronic structures and profiles of the absorption spectra. This was interpreted in terms of hot-band, ground to excited singlet state transitions from energetically closely-spaced torsional vibrational levels of the vinylene double bond in the ground state. The shapes of the absorption bands affect the overlaps of the absorption and fluorescence spectra. This has been quantified as the probability of fluorescence reabsorption in solid polymer films as a function of pathlength. This is an important determinant of the efficacies of these compounds for "harvesting" solar energy in luminescent solar concentrator systems. The reabsorption probabilities of these compounds are lower for all pathlengths than those determined in the same polymer film for the fluorophores, perylene and perylene diimide, which have been considered for concentrating spatially diffuse sunlight.


Assuntos
Fluorescência , Polímeros/química , Estilbenos/química , Absorção Fisico-Química , Estrutura Molecular , Processos Fotoquímicos , Espectrometria de Fluorescência
14.
J Org Chem ; 79(21): 10153-69, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25265243

RESUMO

We report details of the synthesis of a series of bi- and trichromophores. These compounds contain mixtures of chromophores that have zwitterionic (ZWI) and neutral ground state (NGS) components covalently attached to each other. The neutral ground state moieties are based on dyes with aniline donors--such as Disperse Red 1--whereas the zwitterionic components are derived from chromophores with pro-aromatic donors such as 1,4-dihydropyridinylidene. By combining both ZWI and NGS components, we aim to develop novel compounds for nonlinear optics in which there is an enhancement of the overall hyperpolarizability coupled with a decrease in the net dipole moment. Thus, this approach should eliminate the electrostatic effects that result when only one type of chromophore is used, and so reduce the likelihood of undesirable aggregation occurring. This, in turn, should enable us to realize organic materials with large macroscopic optical nonlinearities. An analysis of the UV-vis results suggests that there is a strong dependence on solvent polarity that determines whether the embedded constituents should be treated as discrete elements; in low polarity solvents, there appear to be strong intramolecular interactions occurring, particularly when a 1,4-quinolinylidene-based donor is used in the ZWI component.

15.
Electron. j. biotechnol ; 17(3): 137-147, May 2014. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-719104

RESUMO

Background ADP-glucose pyrophosphorylase (AGPase) is a rate-limiting enzyme catalyzing the first step in the starch biosynthesis pathway in higher plants. To date, there are no reported variants or isoforms of the AGPase enzyme in bananas (Musa spp. family Musaceae) as is the case of other plants. In this study, genomic DNA sequences homologous to the gene encoding one of the large subunits of the enzyme were amplified from 10 accessions of the genus Musa, including representatives of wild ancestors (AA and BB genomes), dessert bananas (AA, AAA, AB and AAB genomes), plantains (AAB genome) and cooking bananas (ABB and AAA genomes), and studied in order to find single nucleotide polymorphisms (SNP) base variations in Musa accessions. Results In the 810-base pair amplicons of the AGPase large sub-unit (LSU) gene analyzed in ten Musa accessions, a total of 36 SNPs and insertions/deletions (indels) were found. The phylogenetic analysis revealed fifteen distinct haplotypes, which were grouped into four variants. Deep examination of SNPs in the 2nd exon in the LSU of AGPase showed that at seven locations, five SNPs altered their amino acid sequence. Conclusions This work reveals the possible number of AGPase enzyme isoforms and their molecular levels in banana. Molecular markers could be designed from SNPs present in these banana accessions. This information could be useful for the development of SNP-based molecular markers for Musa germplasm, and alteration of the allosteric properties of AGPase to increase the starch content and manipulate the starch quality of banana fruits.


Assuntos
Amido/metabolismo , Polimorfismo de Nucleotídeo Único , Glucose-1-Fosfato Adenililtransferase/genética , Filogenia , Variação Genética , Haplótipos , Marcadores Genéticos , Reação em Cadeia da Polimerase , Clonagem Molecular , Musa , Genótipo
16.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 1): o29-30, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24526976

RESUMO

In the title mol-ecule, C48H42N4O5, a potential non-linear optical compound, the furan ring [r.m.s. deviation = 0.010 (1) Å] and the indolyl-idene ring system [r.m.s. deviation = 0.013 (2) Å] are inclined to one another by 18.52 (6)°. This is similar to the arrangement [16.51 (18)°] found for the N-hy-droxy-ethyl adduct of the title compound [Bhuiyan et al. (2011 ▶). Mol. Cryst. Liq. Cryst. 548, 1-12]. Replacing the hy-droxy-ethyl group with 3,5-di-benzyl-oxybenzoate has not resulted in a non-centrosymmetric lattice arrangement or significant changes to the basic mol-ecular structure. In the crystal, mol-ecules are linked via pairs of C-H⋯N hydrogen bonds, forming inversion dimers with an R (2) 2(20) ring motif. The dimers are linked via C-H⋯O hydrogen bonds, forming C(17) chains along [010]. The chains are linked by further C-H⋯N hydrogen bonds, forming layers parallel to (001) and enclosing R 2 (2)(44) ring motifs. There are also C-H⋯π inter-actions present, stabilizing the inter-layer orientation of the pendant bis-(benz-yloxy)benzo-yloxy group.

17.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 1): o45-6, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24526989

RESUMO

The title compound, C25H24N4O2, adopts a cisoid configuration and has twofold orientational disorder of the 2-hy-droxy-ethyl group. The mol-ecule is twisted from planarity so that the dihedral angle between the terminating indol-2-yl-idene and the furan-2-yl-idene moiety mean planes is 12.75 (7)°. Conformational disorder occurs at the indol-2-yl-idene N atom, which results in two orientations for the hy-droxy-ethyl group [occupancy ratio = 0.896 (2):0.104 (2)], and the hy-droxy O atom of the 2-hy-droxy-ethyl group is located over three sites [occupancy ratio = 0.548 (2):0.348 (2):0.104 (2)]. An intra-molecular C-H⋯O hydrogen bond involving the lowest occupancy hy-droxy O atom is observed. In the crystal, the mol-ecules pack in parallel dimeric sheets about centres of symmetry, utilizing O-H⋯N(cyano), C-H⋯N(cyano) and O-H⋯O hydrogen bonds, in two sets parallel to (02-1) and (021) planes.

18.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 1): o83-4, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24527014

RESUMO

The title compound, C18H23N2O2 (+)·Cl(-), crystallizes with two independent cations and anions per cell. Each cation has twofold rotational disorder about the linking vinyl groups but with unequal occupancies [0.963 (5):0.037 (5) and 0.860 (8):0.140 (8)]. The two independent cations are close to being related by an inversion centre but the data does not support the expected centrosymmetric space-group assignment. The conclusion is that the differing rotational disorder has lead to an overall non-centrosymmetric lattice. In the crystal, the mol-ecules pack in layers parallel to (133) and (-13-3), chain-linked with motif C (1) 2(7) by the di-hydroxy-propyl O-H⋯Cl⋯H-O hydrogen bonds. Other lattice binding is provided by O-H⋯Cl, C-H⋯Cl and C-H⋯N inter-actions.

19.
Artigo em Inglês | MEDLINE | ID: mdl-24098196

RESUMO

The title compound, C20H21N3O, has crystallographic mirror symmetry with all non-H atoms apart from the methyl C atom of the CMe2 group lying on the mirror plane. Mol-ecules are linked into planar sheets parallel to (010) by phen-yl-azo C-H⋯N and phen-yl-ethanone C-H⋯O inter-actions. Methyl C-H⋯π inter-actions provide crosslinking between the planes.

20.
Artigo em Inglês | MEDLINE | ID: mdl-24046704

RESUMO

Mol-ecules of the potential non-linear optical title compound, C13H9N3O3, form dimeric stacks of mol-ecules along the a axis cross-linked around inversion centers by N-H⋯O hydrogen bonds and weak (phen-yl)C-H⋯O inter-molecular inter-actions, forming a 'collaboration' of R 2 (2)(8) and R 2 (2)(16) ring motifs. The mol-ecules are then further linked by weak C-H⋯O and C-H⋯N inter-actions into sheets parallel to (121).

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