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1.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 4): 292-296, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-37057003

ABSTRACT

The title compound, C20H21F3N2O4, features a main twelve-membered difuryl ring with which the furan rings make dihedral angles of 76.14 (5) and 33.81 (5)°. The dihedral angle between the furan rings is 42.55 (7)°. The six-membered nitro-gen heterocycle has a twist-boat conformation. In the crystal, pairs of mol-ecules are connected by inter-molecular C-H⋯O inter-actions, generating an R 2 2(14) ring motif. These pairs of mol-ecules form zigzag chains along the a-axis direction by means of C-H⋯F inter-actions. Furthermore, C-H⋯π and C-F⋯π inter-actions link the mol-ecules into chains along the b-axis direction, forming sheets parallel to the (001) plane. These sheets are also connected by van der Waals inter-actions.

2.
Adv Colloid Interface Sci ; 304: 102667, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35462268

ABSTRACT

The development of functional materials with uniquely advanced properties lies at the core of nanoscience and nanotechnology. From the myriad possible combinations of organic and/or inorganic blocks, hybrids combining metal nanoclusters and carbon nanomaterials have emerged as highly attractive colloidal materials for imaging, sensing (optical and electrochemical) and catalysis, among other applications. While the metal nanoclusters provide extraordinary luminescent and electronic properties, the carbon nanomaterials (of zero, one or two dimensions) convey versatility, as well as unique interfacial, electronic, thermal, optical, and mechanical properties, which altogether can be put to use for the desired application. Herein, we present an overview of the field, for experts and non-experts, encompassing the basic properties of the building blocks, a systematic view of the chemical preparation routes and physicochemical properties of the hybrids, and a critical analysis of their ongoing and emerging applications. Challenges and opportunities, including directions towards green chemistry approaches, are also discussed.


Subject(s)
Carbon , Nanostructures , Carbon/chemistry , Catalysis , Metals/chemistry , Nanostructures/chemistry , Nanotechnology
3.
Nature ; 583(7818): 780-784, 2020 07.
Article in English | MEDLINE | ID: mdl-32728238

ABSTRACT

In the regime of deep strong light-matter coupling, the coupling strength exceeds the transition energies of the material1-3, fundamentally changing its properties4,5; for example, the ground state of the system contains virtual photons and the internal electromagnetic field gets redistributed by photon self-interaction1,6. So far, no electronic excitation of a material has shown such strong coupling to free-space photons. Here we show that three-dimensional crystals of plasmonic nanoparticles can realize deep strong coupling under ambient conditions, if the particles are ten times larger than the interparticle gaps. The experimental Rabi frequencies (1.9 to 3.3 electronvolts) of face-centred cubic crystals of gold nanoparticles with diameters between 25 and 60 nanometres exceed their plasmon energy by up to 180 per cent. We show that the continuum of photons and plasmons hybridizes into polaritons that violate the rotating-wave approximation. The coupling leads to a breakdown of the Purcell effect-the increase of radiative damping through light-matter coupling-and increases the radiative polariton lifetime. The results indicate that metallic and semiconducting nanoparticles can be used as building blocks for an entire class of materials with extreme light-matter interaction, which will find application in nonlinear optics, the search for cooperative effects and ground states, polariton chemistry and quantum technology4,5.

4.
Faraday Discuss ; 214(0): 159-173, 2019 05 23.
Article in English | MEDLINE | ID: mdl-30912539

ABSTRACT

An ideal plasmonic system for hot-electron generation allows the optical excitation of plasmons, limits radiation losses, exhibits strong non-radiative electron damping, and is made from scalable and cost-effective materials. Here we demonstrate the optical excitation of dark interlayer plasmons in bilayers of colloidal gold nanoparticles. This excitation is created by an antiparallel orientation of the dipole moments in the nanoparticle layers; it is expected to exhibit strongly reduced radiative damping. Despite the vanishing dipole moment, an incoming electromagnetic wave that is propagating normal to the surface will excite the dark mode due to field retardation. We observe a strong peak in the absorption spectrum of a colloidal gold bilayer (nanoparticle diameter = 46 nm); this peak is absent for a nanoparticle monolayer. The full width at half maximum of the dark mode is 230 meV for an ideal nanoparticle crystal and 320 meV for the structure produced by self-assembly out of solution. The position and width of the dark plasmon are efficiently tailored by the interparticle distance within the layer, nanoparticle size and layer number. We present time-resolved pump and probe experiments of hot-electron generation by bright and dark bilayer nanoparticle modes.

5.
ACS Omega ; 3(1): 863-871, 2018 Jan 31.
Article in English | MEDLINE | ID: mdl-31457933

ABSTRACT

This work describes the preparation of a series of platinum-aminocarbene complexes [PtCl{C(N=C a (C6R2R3R4R5CON b ))=N(H)R1}(CNR1)] a-b (8-19, 65-75% isolated yield) via the reaction of cis-[PtCl2(CNR1)2] (R1 = Cy 1, t-Bu 2, Xyl 3, 2-Cl-6-MeC6H3 4) with 3-iminoisoindolin-1-ones HN=C a (C6R2R3R4R5CON b H) (R2-R5 = H 5; R3 = Me, R2, R4, R5 = H 6; R3, R4 = Cl, R2, R5 = H 7). New complexes 17-19 were characterized by elemental analyses (C, H, N), ESI+-MS, Fourier transform infrared spectroscopy (FT-IR), one-dimensional (1H, 13C{1H}), and two-dimensional (1H,1H correlation spectroscopy (COSY), 1H,13C heteronuclear multiple quantum correlation (HMQC)/1H,13C heteronuclear single quantum coherence (HSQC), 1H,13C heteronuclear multiple bond correlation (HMBC)) NMR spectroscopy, and authenticity of known species 8-16 was confirmed by FT-IR and 1H and 13C{1H} NMR. Complexes 8-19 were assessed as catalysts for hydrosilylation of terminal alkynes with hydrosilanes to give vinyl silanes, and complex [PtCl{C(N=C a (C6H3(5-Me)CON b ))=N(H)(2-Cl-6-MeC6H3)}{CN(2-Cl-6-MeC6H3)}] a-b (18) showed the highest catalytic activity. The catalytic system proposed operates at 80-100 °C for 4-6 h in toluene and with catalyst loading of 0.1 mol %, enabling the reaction of a number of terminal alkynes (PhC≡CH, t-BuC≡CH, and 4-(t-Bu)C6H4C≡CH) with hydrosilanes (Et3SiH, Pr3SiH, i-Pr3SiH, and PhMe2SiH). Target vinyl silanes were prepared in 48-95% yields (as a mixture of α/ß isomers) and with maximum turnover number of 8.4 × 103. Hydrosilylation of internal alkynes (PhC≡CPh, Me(CH2)2C≡C(CH2)2Me, and PhC≡CMe) with hydrosilanes (Et3SiH, PhMe2SiH) led to the corresponding trisubstituted silylated alkenes in 86-94% yields. Initial observations on the mechanism of the catalytic action of platinum-ADC catalysts 8-19 suggested a molecular catalytic cycle.

6.
J Inorg Biochem ; 166: 34-48, 2017 01.
Article in English | MEDLINE | ID: mdl-27815980

ABSTRACT

Synthesis and spectroscopic properties of seven new dibutyltin(IV) compounds of 2-{(E)-4-hydroxy-3-[(E)-4-(aryl)iminomethyl]phenyldiazenyl}benzoic acids (LnHH'; n=2-8) with general formula {[Bu2Sn(LnH)]2O}2 (1-7) are reported. The compounds were characterized by elemental analysis and by UV-Visible, fluorescence, IR, 1H, 13C and 119Sn NMR spectroscopies. Solid state structures of dibutyltin(IV) compounds 1-3, 6 and 7 were accomplished from single crystal X-ray crystallography which reveal the common ladder-type structure with two endo- and two exo-Sn atoms. The redox properties of LnHH' (n=2-4, 7 and 8) and their diorganotin(IV) compounds 1-3, 6 and 7 were also investigated by cyclic voltammetry. In general, the dibutyltin(IV) derivatives exhibited significant in vitro cytotoxic potency towards A375 (melanoma) and HCT116 (colon carcinoma) cell lines as determined by several experiments, like Live and Dead assay, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) cell viability assay, LDH (lactate dehydrogenase), cleavage of caspases and PARP (poly(ADP-ribose)polymerase), and DNA fragmentation. Dibutyltin(IV) compounds increase cell death without cytolysis and decreases membrane fluidity, without interfering with p53. Among the dibutyltin(IV) compounds, compound 6 was found to be the most potent, with an IC50 value of 78nM. A mechanism of action for tumor cell death is proposed.


Subject(s)
Antineoplastic Agents , Colonic Neoplasms/drug therapy , Cytotoxins , Melanoma/drug therapy , Organotin Compounds , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Cell Membrane/metabolism , Cell Membrane/pathology , Cell Survival/drug effects , Colonic Neoplasms/metabolism , Colonic Neoplasms/pathology , Crystallography, X-Ray , Cytotoxins/chemical synthesis , Cytotoxins/chemistry , Cytotoxins/pharmacology , Drug Screening Assays, Antitumor , Humans , Magnetic Resonance Spectroscopy , Melanoma/metabolism , Melanoma/pathology , Membrane Fluidity/drug effects , Molecular Structure , Organotin Compounds/chemical synthesis , Organotin Compounds/chemistry , Organotin Compounds/pharmacology , Tumor Suppressor Protein p53/metabolism
7.
Dalton Trans ; 43(40): 15192-200, 2014 Oct 28.
Article in English | MEDLINE | ID: mdl-25185114

ABSTRACT

The Ni(II) and Zn(II) complexes [MCl(Tpms(Ph))] (Tpms(Ph) = SO3C(pz(Ph))3, pz = pyrazolyl; M = Ni 2 or Zn 3) and the Cu(II) complex [CuCl(Tpms(Ph))(H2O)] (4) have been prepared by treatment of the lithium salt of the sterically demanding and coordination flexible tris(3-phenyl-1-pyrazolyl)methanesulfonate (Tpms(Ph))(-) (1) with the respective metal chlorides. The (Tpms(Ph))(-) ligand shows the N3 or N2O coordination modes in 2 and 3 or in 4, respectively. Upon reaction of 2 and 3 with Ag(CF3SO3) in acetonitrile the complexes [M(Tpms(Ph))(MeCN)](CF3SO3) (M = Ni 5 or Zn 6, respectively) were formed. The compounds were obtained in good yields and characterized by analytic and spectral (IR, (1)H and (13)C{(1)H} NMR, ESI-MS) data, density functional theory (DFT) methods and {for 4 and [(n)Bu4N](Tpms(Ph)) (7), the latter obtained upon Li(+) replacement by [(n)Bu4N](+) in Li(Tpms(Ph))} by single crystal X-ray diffraction analysis. The Zn(II) and Cu(II) complexes (3 and 4, respectively) act as efficient catalyst precursors for the diastereoselective nitroaldol reaction of benzaldehydes and nitroethane to the corresponding ß-nitroalkanols (up to 99% yield, at room temperature) with diastereoselectivity towards the formation of the anti isomer, whereas the Ni(II) complex 2 only shows a modest catalytic activity.


Subject(s)
Copper/chemistry , Heterocyclic Compounds, 3-Ring/chemistry , Nickel/chemistry , Nitro Compounds/chemistry , Zinc/chemistry , Catalysis , Crystallography, X-Ray , Ligands , Mesylates/chemistry , Models, Molecular , Stereoisomerism
8.
Chemistry ; 20(13): 3689-704, 2014 Mar 24.
Article in English | MEDLINE | ID: mdl-24616192

ABSTRACT

[RuCl(arene)(µ-Cl)]2 dimers were treated in a 1:2 molar ratio with sodium or thallium salts of bis- and tris(pyrazolyl)borate ligands [Na(Bp(Br3))], [Tl(Tp(Br3))], and [Tl(Tp(iPr, 4Br))]. Mononuclear neutral complexes [RuCl(arene)(κ(2)-Bp(Br3))] (1: arene=p-cymene (cym); 2: arene=hexamethylbenzene (hmb); 3: arene=benzene (bz)), [RuCl(arene)(κ(2)-Tp(Br3))] (4: arene=cym; 6: arene=bz), and [RuCl(arene)(κ(2)-Tp(iPr, 4Br))] (7: arene=cym, 8: arene=hmb, 9: arene=bz) have been always obtained with the exception of the ionic [Ru2 (hmb)2-(µ-Cl)3][Tp(Br3)] (5'), which formed independently of the ratio of reactants and reaction conditions employed. The ionic [Ru-(CH3OH)(cym)(κ(2)-Bp(Br3))][X] (10: X=PF6, 12: X=O3SCF3) and the neutral [Ru(O2CCF3)(cym)(κ(2)-Bp(Br3))] (11) have been obtained by a metathesis reaction with corresponding silver salts. All complexes 1-12 have been characterized by analytical and spectroscopic data (IR, ESI-MS, (1)H and (13)C NMR spectroscopy). The structures of the thallium and calcium derivatives of ligand Tp(Br3), [Tl(Tp(Br3))] and [Ca(dmso)6][Tp(Br3)]2 ⋅2 DMSO, of the complexes 1, 4, 5', 6, 11, and of the decomposition product [RuCl(cym)(Hpz(iPr, 4Br))2][Cl] (7') have been confirmed by using single-crystal X-ray diffraction. Electrochemical studies showed that 1-9 and 11 undergo a single-electron Ru(II) →Ru(III) oxidation at a potential, measured by cyclic voltammetry, which allows comparison of the electron-donor characters of the bis- and tris(pyrazol-1-yl)borate and arene ligands, and to estimate, for the first time, the values of the Lever EL ligand parameter for Bp(Br3), Tp(Br3), and Tp(iPr, 4Br). Theoretical calculations at the DFT level indicated that both oxidation and reduction of the Ru complexes under study are mostly metal-centered with some involvement of the chloride ligand in the former case, and also demonstrated that the experimental isolation of the µ(3)-binuclear complex 5' (instead of the mononuclear 5) is accounted for by the low thermodynamic stability of the latter species due to steric reasons.


Subject(s)
Borates/chemical synthesis , Organometallic Compounds/chemical synthesis , Pyrazoles/chemistry , Ruthenium/chemistry , Borates/chemistry , Ligands , Magnetic Resonance Spectroscopy , Models, Chemical , Molecular Structure , Organometallic Compounds/chemistry , Thermodynamics
12.
Rev. esp. cir. oral maxilofac ; 31(4): 257-263, jul.-ago. 2009. tab, ilus
Article in Spanish | IBECS | ID: ibc-77239

ABSTRACT

La Úlcera Eosinófila de la Mucosa Oral, es una entidad pocofrecuente, pobremente descrita en la literatura mundial. Se define como unalesión benigna autolimitada que si bien puede presentarse en distintas áreasde la cavidad bucal, presenta una marcada predilección por la mucosa ventralde la lengua. Clínicamente, se presenta como una lesión ulcerada de bordesindurados y sobreelevados. Los hallazgos histopatológicos son característicosy consisten en un infiltrado mixto rico en eosinófilos, acompañadode una población de grandes células mononucleadas. Recientes artículosbasados en estudios inmunohistoquimicos, permiten afirmar la presencia degrandes linfocitos atípicos CD30+ y por lo tanto, incluir esta lesión en el espectrode las entidades simuladoras de desordenes linfoproliferativos.A pesar de esto, el mecanismo etiopatogenico permanece oscuro y el traumalocal juega un rol todavía no dilucidado; aunque se halla presente en lamayoría de las publicaciones, explicando el fenómeno como un mecanismoreactivo. La importancia de esta lesión, radica en su diagnostico diferencialpor su semejanza clínica al carcinoma espinocelular, histoplasmosis, chancrosifilítico, Úlcera tuberculosa, carcinoma epidermoide y otras.En nuestro trabajo se revisa la literatura y se discuten la características clínicas,histopatológicas y alternativas terapéuticas, a partir del artículo de uncaso clínico en una paciente joven, que luego de la biopsia escisión comométodo para el diagnostico de certeza, se produce una recidiva de la lesión;lo que orientó el tratamiento hacia la cirugía combinada con corticoterapialocal intralesional, logrando su remisión(AU)


Eosinophilic Ulcer of the Oral Mucosa, an entity, poorlydeciphers in world-wide literature. It is defined as a self-limited,benign injury that although it can appear in different areas of thebuccal cavity it presents a noticeable predilection via the ventralmucosa of the tongue. Clinically, one looks like an ulcer with hardand risen edges. The histo-pathological findings are typical andconsist of a rich infiltrated mix of eosinophils, as well as a populationof large mononuclear cells. Recent reports based onimmunohistochemical studies allow us to confirm the presence oflarge atypical lymphocytes CD30+ and therefore include this lesioninjury in the spectrum of lympho proliferative disorder simulators.Despite this the etiopathogenic mechanism remains unknown andlocal trauma still plays an unexplained roll; although the majorityof publications have explained the phenomena as a reactivemechanism. The importance of this injury is established by itsdifferential diagnostic because of its clinical similarity to SpinocellularCarcinoma, Histoplasmosis, syphilitic chancre, Ulcer Tuberculosis,Epidermoid Carcinoma and others. In our work the literature isreviewed and clinical characteristics, histo-pathologies and alternativetherapies are discussed. We use the case of a young patient whohas a biopsy in an effort to diagnose with certainty has a relapseof the lesion which directs the treatment towards combined surgeryand local intra lesion cortico therapy which led to successful remission(AU)


Subject(s)
Humans , Female , Adolescent , Eosinophilia/complications , Oral Ulcer/surgery , Surgical Flaps , Adrenal Cortex Hormones/therapeutic use , Diagnosis, Differential , Trismus/etiology , Edema/etiology
13.
Appl Psychophysiol Biofeedback ; 22(3): 209-14, 1997 Sep.
Article in English | MEDLINE | ID: mdl-9428970

ABSTRACT

Studies that have examined the relationship between personality characteristics and tension headache have arrived at conflicting and, for the most part, negative results. In recent years, a number of investigators have begun examining the relationship between anger and psychophysiological disorders, focusing mostly on anger which is suppressed or held in rather than expressed behaviorally. The present study explored the relationship between anger in 59 tension headache subjects and compared their results to 33 nonpain controls. Materials consisted of the revised research edition of the Spielberger State-Trait Anger Expression Inventory. As predicted, tension headache sufferers were found to have significantly more anger held inward than nonpain controls. Implications for applied psychophysiology treatment and future research directions are discussed.


Subject(s)
Anger , Psychophysiology/methods , Tension-Type Headache/psychology , Adult , Aged , Female , Humans , Male , Middle Aged
14.
Headache ; 35(7): 411-9, 1995.
Article in English | MEDLINE | ID: mdl-7672959

ABSTRACT

This study is the first systematic examination of a trapezius EMG biofeedback training regimen with tension headache sufferers. It evaluated the differential effects of three psychophysiological treatments for tension headache: (1) a standard 12-session frontal EMG biofeedback training regimen (n = 8), (2) a 12-session upper trapezius EMG biofeedback training regimen (n = 10), and (3) a standard seven-session progressive muscle relaxation therapy regimen (n = 8). Posttreatment assessment at 3 months following cessation of treatment revealed clinically significant decreases in overall headache activity (50% or greater) in 50% of subjects in the frontal biofeedback group, 100% in the trapezius biofeedback group, and 37.5% in the relaxation therapy group. Chi-squared analyses indicated that the trapezius biofeedback group was more effective in obtaining significant clinical improvement than the frontal biofeedback and relaxation therapy groups (which did not differ from each other). The three treatments did not differ on secondary measures of headache improvement (number of headache-free days, peak headache activity, and medication index). Implications for the psychophysiological treatment of tension headache, as well as future research directions, are discussed.


Subject(s)
Biofeedback, Psychology/methods , Relaxation Therapy , Tension-Type Headache/therapy , Adult , Chronic Disease , Electrodes , Electromyography , Female , Humans , Male , Medical Records , Middle Aged , Muscles/physiopathology , Tension-Type Headache/physiopathology , Treatment Outcome
15.
Int J Psychophysiol ; 17(2): 153-7, 1994 Jul.
Article in English | MEDLINE | ID: mdl-7995777

ABSTRACT

A number of investigators in recent years have called for the development of devices that can monitor surface EMG levels in individuals' normal environments for use with patients who suffer from disorders in which the etiology or maintenance of the pathology is presumed to be due at least in part to musculoskeletal dysfunction, such as low back pain, phantom limb pain and tension headache. This study examined the test-retest reliability of just such a device. Twenty-six healthy controls wore a lightweight (24 ounce) device which measured bilateral upper trapezius EMG, as well as peak and integral motion, for 5 consecutive days for up to 18 h each day. ANOVAs on the four measures revealed no difference between any of the four measures over the 5 days. Intra-class correlation coefficients for the two EMG variables across 5 days were both significant with alpha levels set at 0.01. The two EMG measures were highly correlated (r = 0.77); the two motion measures were also highly correlated (r = 0.60), but at a lower magnitude than EMG values; the relationship between EMG and motion was significant, but the magnitude of the between EMG motion correlations (0.26 and 0.35) were lower than the within EMG or motion ones. It was concluded that the test-retest reliability of the ambulatory monitoring device is within acceptable limits. Implications for the use of the device with musculoskeletal pain disorders--particularly headache--are discussed.


Subject(s)
Electromyography/instrumentation , Monitoring, Ambulatory/instrumentation , Musculoskeletal Diseases/diagnosis , Pain/diagnosis , Adult , Aged , Analysis of Variance , Electrodes , Female , Headache/diagnosis , Humans , Male , Middle Aged , Muscle, Skeletal/physiopathology , Musculoskeletal Diseases/physiopathology , Pain/physiopathology , Reproducibility of Results
16.
Biofeedback Self Regul ; 16(4): 379-90, 1991 Dec.
Article in English | MEDLINE | ID: mdl-1760459

ABSTRACT

This study evaluated the effects of a 12-session frontal electromyographic biofeedback training regimen on the headache activity of eight tension headache sufferers aged 62 and older. The biofeedback sessions were slightly modified for a geriatric population, essentially to increase comprehension and retention of rationale and instructions. Post-treatment assessment at three months revealed significant decreases in overall headache activity (50% or greater) in 50% of the subjects, and moderate improvement (35%-45%) in three of the remaining four subjects. Significant clinical and/or statistical pre-post differences were also found for the number of headache-free days, peak headache activity, and medication index. This is the first prospective study of biofeedback training for tension headache in an elderly population and, unlike previous retrospective studies, suggests that such therapy may be an effective intervention in the treatment of tension headaches in the elderly.


Subject(s)
Biofeedback, Psychology/methods , Headache/therapy , Aged , Electromyography , Female , Humans , Male , Middle Aged , Prognosis , Prospective Studies
17.
J Psychosom Res ; 35(2-3): 187-95, 1991.
Article in English | MEDLINE | ID: mdl-2046052

ABSTRACT

This paper presents the results of two studies. In the first, 20 tension headache subjects were evaluated in both a headache and non-headache state on bilateral trapezius and unilateral frontalis electromyographic activity during six positions: standing, bending from the waist, rising, sitting with back unsupported, sitting with back supported, and prone. Results indicated no effect of headache state on either measure. In a second study, 11 of the tension headache sufferers in Study One and 11 age-matched controls were compared on the same measures (controls were assessed two times, with a one-week duration separating evaluations). Results indicated a diagnosis by position interaction, with post-hoc tests revealing the muscle activity of tension headache sufferers to be considerably higher during the prone position than that of non-headache controls. Non-significant trends were found when examining the data for clinically significant abnormalities (90% of the headache sufferers were found to have significant clinical abnormalities).


Subject(s)
Arousal/physiology , Electromyography , Headache/physiopathology , Muscle Contraction/physiology , Posture/physiology , Adult , Facial Muscles/physiopathology , Female , Headache/psychology , Humans , Male , Middle Aged
18.
Int J Psychophysiol ; 9(1): 31-7, 1990 Jul.
Article in English | MEDLINE | ID: mdl-2142149

ABSTRACT

This paper presents the results of two studies in which bilateral surface EMG recordings of paraspinal muscle tension were measured in 29 lower back pain and 20 normal subjects in 6 different positions (standing, bending from the waist, rising, sitting with back supported, sitting unsupported, prone) on two occasions, and a comparison of the data from both studies. Measures were highly reliable when examined using analysis of variance procedures. Statistically significant reliability coefficients were obtained when the absolute values of the measures were examined, although in some instances less than 20% of the variance was explained. When examined as relative [percent change from baseline (prone) condition] values, differences between the two groups were observed: the normals were statistically more reliable than lower back pain subjects during every condition. Implications for clinical work and both basic and applied research are discussed.


Subject(s)
Back Pain/physiopathology , Electromyography/methods , Muscles/physiopathology , Posture , Adult , Back Pain/etiology , Female , Humans , Male , Middle Aged , Muscles/physiology
19.
J Psychosom Res ; 34(1): 71-7, 1990.
Article in English | MEDLINE | ID: mdl-2313614

ABSTRACT

This study reports the results of the first investigation into the relationship between situational stress and phantom limb pain. Twenty-seven male amputees recorded their pain and overall stress levels daily for 180 days using a 1-10 rating scale. Three possible relationships into the etiology and/or maintenance of phantom limb pain were examined using cross-lagged correlational techniques: an isomorphic relationship (same time increases in pain lead to same time increases in stress and vice versa), a consequence relationship (increases in pain precede increases in stress), and a precursor relationship (increases in stress precede increases in pain). Thirty-seven per cent of subjects demonstrated some significant precursor relationship. Although support was found for all three hypotheses, the most frequently observed relationship was the isomorphic one. Seventy-four per cent of subjects demonstrated some significant stress-pain relationship. The results lend support to the psychological theory underlying the use of psychophysiological interventions such as biofeedback and relaxation therapy in amputees with phantom limb pain.


Subject(s)
Pain Measurement/methods , Phantom Limb/psychology , Stress, Psychological/complications , Adult , Aged , Arousal , Follow-Up Studies , Humans , Individuality , Male , Middle Aged , Personality Tests
20.
J Rehabil Res Dev ; 25(2): vii-x, 1988.
Article in English | MEDLINE | ID: mdl-3361454

ABSTRACT

Recent findings suggest that major misunderstandings concerning the prevalence, characteristics, etiology, and treatment effectiveness of phantom pain have led to the widespread mismanagement of amputees throughout the history of modern medicine. For years it has been believed that phantom pain is relatively rare, is of unknown etiology, and probably has a psychological basis. Research results over the last few years, however, suggest that phantom pain is widely prevalent among individuals with amputations and most likely has a physiological basis. Although many different treatments have been introduced recently, few, if any, have yet been documented as effective due to lack of rigorous follow-up studies. Future progress in clinical treatment and increased scientific understanding of phantom pain will require an examination of some of the factors that have led to past confusion regarding scientific research on and clinical treatment of phantom pain.


Subject(s)
Amputation, Surgical/rehabilitation , Phantom Limb/therapy , Chronic Disease , Combined Modality Therapy , Humans , Phantom Limb/psychology , Psychophysiologic Disorders/therapy , Research
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