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The crystal packing of organic chromophores has a profound impact on their photophysical properties. Molecular crystal engineering is generally incapable of producing precisely spaced arrays of molecules for use in photovoltaics, light-emitting diodes, and sensors. A promising alternative strategy is the incorporation of chromophores into crystalline metal-organic frameworks (MOFs), leading to matrix coordination-induced emission (MCIE) upon confinement. However, it remains unclear how the precise arrangement of chromophores and defects dictates photophysical properties in these systems, limiting the rational design of well-defined photoluminescent materials. Herein, we report new, robust Zr-based MOFs constructed from the linker tetrakis(4-carboxyphenyl)ethylene (TCPE4-) that exhibit an unexpected structural transition in combination with a prominent shift from green to blue photoluminescence (PL) as a function of the amount of acid modulator (benzoic, formic, or acetic acid) used during synthesis. Time-resolved PL (TRPL) measurements provide full spectral information and reveal that the observed hypsochromic shift arises due to a higher concentration of linker substitution defects at higher modulator concentrations, leading to broader excitation transfer-induced spectral diffusion. Spectral diffusion of this type has not been reported in a MOF to date, and its observation provides structural information that is otherwise unobtainable using traditional crystallographic techniques. Our findings suggest that defects have a profound impact on the photophysical properties of MOFs and that their presence can be readily tuned to modify energy transfer processes within these materials.
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Estruturas Metalorgânicas , Ácido Acético , Ácido Benzoico , Cristalografia , DifusãoRESUMO
INTRODUCTION: The quantitative measurement of the left ventricle by echocardiography is a fundamental tool in the diagnosis and prognosis of acquired and congenital diseases in the pediatric population. The objective of this study was to validate an automated three-dimensional adaptive analytic echocardiographic algorithm, the so-called Heart Model® (HM) in the pediatric population, using as comparators the left atrial and left ventricular volumes and left ventricular ejection fraction obtained by means of conventional 2D and 3D echocardiography. METHODS: Pilot study, where a population comprised of 75 consecutive patients aged 6-17 years who attended a pediatric cardiology clinic, was evaluated. Every patient underwent a conventional 2D and 3D echocardiography and an analysis using HM. Conventional 3D echo was used as the reference method. RESULTS: Seventy-five patients were analyzed. Mean age was 11.2 (4.0) years (52.2% women). The intraclass correlation coefficient of HM vs 2D echo was poor, but it was good for the agreement between HM and 3D echo for left ventricular end-diastolic volume (ICC: 0.98; 95% CI: 0.97-0.99; P < 0.001), left ventricular end-systolic volume ICC: 0.98; 95% CI: 0.96-0.99; P = 0.001), and left ventricular ejection fraction (ICC: 0.87; 95% CI: 0.78-0.92; P < 0.001). The agreement was also good for the three parameters when the analysis was performed according to body weight. CONCLUSIONS: Heart Model® is a feasible and accurate tool for the evaluation of left atrial and left ventricular volumes and left ventricular ejection fraction in pediatric population aged above 6 years.
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Ecocardiografia Tridimensional/métodos , Ventrículos do Coração/diagnóstico por imagem , Função Ventricular Esquerda/fisiologia , Adolescente , Algoritmos , Criança , Ecocardiografia/métodos , Estudos de Avaliação como Assunto , Estudos de Viabilidade , Feminino , Humanos , Masculino , Projetos Piloto , Reprodutibilidade dos TestesRESUMO
The ghost crab Ocypode quadrata is a relevant species in the Western Atlantic beaches, and has been proposed as an indicator of human impact in these ecosystems. Eventhough some studies have covered various aspects of its natural history, no evaluations on the effects of human disturbance on its population dynamics have been made. This work compared the abundance, growth, and mortality of O. quadrata in two disturbed beaches (Aventuras and Majahual) and two preserved beaches (Xcacel and Puerto Angel) from the Mexican Caribbean. For this, nine samplings were made on each beach (every two to three months) between March 2013 and November 2014. Crabs were collected manually by three people, during the night first hours and for one hour, and a total area of 9 000 m2 per beach. The crabs were measured, weighed, and separated into three groups: juvenile, male and female; while abundance was estimated by the number of collected crabs, and growth parameters were estimated using length frequencies. A total of 1 047 crabs were sampled in the four beaches; a higher crab abundance was found in the preserved beaches, but significant differences were only found between Puerto Angel and Majahual (Tukey, p<0.05). The adult-juvenile ratio was 1:1 in Xcacel and Aventuras, while in Majahual, more juveniles than adults were collected; and Puerto Angel had more adults than the juveniles. The size structure at Xcacel ranged from 4-32 mm, but in the rest of the beaches the minimum size was 5 mm. The maximum size at Aventuras, Majahual and Puerto Angel were 27 mm, 25 mm and 30 mm, respectively. The modal progression analysis of length's pooled data, revealed the presence of at least two groups of ages in all beaches. For all beaches, individuals smaller than 10 mm length were collected in almost all sampling months, indicating a continuous recruitment throughout the year. The length-weight relationship of the ghost crab was found isometric in the two preserved beaches, and negative allometric at the two impacted beaches. Crabs from Puerto Angel showed the highest body condition (Tukey, p<0.05). K-values ranged from 0.6-0.97/year and L∞ from 29.0 mm to 33.6 mm with higher values for the two preserved beaches. The highest mortality values were found in Xcacel and Aventuras. In the disturbed beaches, the destruction of the dunes, the mechanical cleaning and the removal of organic matter, seem to be the main causes that lead to a low abundance of crabs, their slower growth and higher mortalities. However, in the best preserved beaches, biological interactions appear to be the most important aspects in regulating the population dynamics of this species. These results supported the information that the ghost crab is a good indicator of human disturbance, and its population changes were clearly measurable and comparable among protected and impacted beaches; these results are also relevant for the management of sandy beaches in the Mexican Caribbean.
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Praias , Braquiúros/fisiologia , Atividades Humanas , Análise de Variância , Animais , Região do Caribe , Conservação dos Recursos Naturais , Meio Ambiente , Feminino , Humanos , Masculino , México , Dinâmica Populacional , Distribuição por SexoRESUMO
The freshwater snail Pomacea flagellata is native from Southeastern Mexico. Studies about this species are scarce and none has treated their reproduction. This snail has been exploited at Bacalar lagoon for many years, leading to a significant decrease in their abundance and currently, a permanent ban was proposed by the government. This work aimed to assess the temporal variations of mating frequency and the abundance of egg clutches of P. flagellata at Bacalar lagoon, as well as their relation with snails density and environmental variables. Sampling was done during the three climatic seasons: Rainy (July, August and September/2012), North or Cold fronts (December/2012 and January and February/2013) and Dry (March, April and May/2013) in 12 sampling stations located along the Bacalar lagoon. On each station a transect of 100 m length was set parallel to the edge, and the number of fresh egg clutches (pink color) laid over vegetation, rocks or manmade structures, were counted. In the water, three 50 x 2 m transects were set and the number of snails were counted as well as the mating frequency. Density of snails varied significantly among seasons, decreasing from the rainy to the dry season. There were no significant differences of snail abundance among months, nested in climatic seasons (ANOVA, p>0.05). During the rainy season the mating frequency was significantly higher than in the Norths, meanwhile in the dry season no mating were registered (Kruskal-Wallis, pË0.05). Eggs clutches appeared from July to March. Density of egg clutches presented no differences between the Rainy and the North seasons (2.72 and 2.93 clutches/m, respectively), nonetheless during the dry season abundance of egg masses was significantly lower (0.1 clutches/m) (H, pË0.05). Mating frequency was related with snail abundance (rs= 0.26; p<0.05) and water temperature (rs= 0.34; p<0.05) and the abundance of egg masses is related with snail abundance (rs= 0.46; p<0.05). In general, we observed that reproductive activity of P. flagellata at Bacalar lagoon is related with the warmer months and with higher rainfall. This finding is relevant to support the management of this resource in the region, so that to implement any management arrangement they must be aware that a temporal ban is necessary during the reproductive season at least.
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Caramujos/fisiologia , Análise de Variância , Animais , Clima , Água Doce , México , Oviposição/fisiologia , Densidade Demográfica , Chuva , Reprodução/fisiologia , Estações do Ano , Estatísticas não Paramétricas , Temperatura , Fatores de TempoRESUMO
Metal-organic frameworks (MOFs) are porous, crystalline materials constructed from organic linkers and inorganic nodes with potential utility in gas separations, drug delivery, sensing, and catalysis. Small variations in MOF synthesis conditions can lead to a range of accessible frameworks with divergent chemical or photophysical properties. New methods to controllably access phases with tailored properties would broaden the scope of MOFs that can be reliably prepared for specific applications. Herein, we demonstrate that simply increasing the reaction concentration during the solvothermal synthesis of M2(dobdc) (M = Mg, Mn, Ni; dobdc4- = 2,5-dioxido-1,4-benzenedicarboxylate) MOFs unexpectedly leads to trapping of a new framework termed CORN-MOF-1 (CORN = Cornell University) instead. In-depth spectroscopic, crystallographic, and computational studies support that CORN-MOF-1 has a similar structure to M2(dobdc) but with partially protonated linkers and charge-balancing or coordinated formate groups in the pores. The resultant variation in linker spacings causes CORN-MOF-1 (Mg) to be strongly photoluminescent in the solid state, whereas H4dobdc and Mg2(dobdc) are weakly emissive due to excimer formation. In-depth photophysical studies suggest that CORN-MOF-1 (Mg) is the first MOF based on the H2dobdc2- linker that likely does not emit via an excited state intramolecular proton transfer (ESIPT) pathway. In addition, CORN-MOF-1 variants can be converted into high-quality samples of the thermodynamic M2(dobdc) phases by heating in N,N-dimethylformamide (DMF). Overall, our findings support that high-concentration synthesis provides a straightforward method to identify new MOFs with properties distinct from known materials and to produce highly porous samples of MOFs, paving the way for the discovery and gram-scale synthesis of framework materials.
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Acid modulation is among the most widely employed methods for preparing metal-organic frameworks (MOFs) that are both stable and highly crystalline, yet there exist few guiding principles for selecting the optimal modulator for a given system. Using the Zr-based MOFs UiO-66 and UiO-68-Me2 (UiO = Universitetet i Oslo) as representative materials, here we present for the first time an in-depth structure-activity study of acid modulators and identify key principles of modulation for the synthesis of highly crystalline Zr-MOFs. By applying whole pattern fitting of powder X-ray diffraction (PXRD) patterns as a technique for evaluating modulator efficacy, complemented by scanning electron microscopy (SEM), 1H NMR, and thermogravimetric analysis (TGA), we demonstrate that the key to effective modulation is competition between the linker and modulator for coordination to the Zr secondary building units (SBUs). Specifically, we illustrate that a close match in pK a and structure between the linker and modulator favors larger and more well-defined crystallites, particularly with sterically unhindered aromatic acid modulators. Based on our findings, we demonstrate that 5-membered heteroaromatic carboxylic acids are among the most efficient acid modulators identified to date for the synthesis of several representative Zr-MOFs with fcu net topologies. In addition, we find that coordination modulation is superior to exogenous acid modulation at higher modulator concentrations. Finally, we compare 1H NMR and TGA as data-driven methods for quantifying linker deficiencies in modulated MOF syntheses. The guiding principles established herein have critical implications for the scalable and controllable synthesis of highly crystalline and stable MOFs relevant to chemical separations, gas storage, and catalysis.
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BACKGROUND: Neuromyelitis Optica Spectrum Disorders (NMOSD) are a group of inflammatory diseases of the Central Nervous System (CNS) that primarily affect the optic nerve and spinal cord, usually with a severe and relapsing course. Due to the scarce information in non-Caucasian populations, we aimed to describe incidence, prevalence, and main clinical characteristics of NMOSD in a defined region in Mexico. MATERIALS AND METHODS: Descriptive, retrospective analysis of all reported cases of NMOSD attended in the neurology department of the UMAE-HE, CMNO, IMSS, the biggest third level hospital in Western Mexico. We searched the electronic medical records of the hospital for patients with a diagnosis of NMO, and reviewed all cases to confirm if they fulfilled NMOSD 2015 diagnostic criteria. Data were collected through a structured form. We described adjusted incidence and prevalence according to the WHO method, for the IMSS affiliated total population in Jalisco state in 2019. RESULTS: 67 NMOSD patients were included in the analysis of clinical data, with a mean age at onset of symptoms of 36 years ((Rivera et al., 2008-65). Most patients were female (74.6%). 53 patients living in Jalisco by the end of 2019 were included in the analysis of prevalence and incidence. Adjusted prevalence was 0.71/100,000 (95% CI 0.55-0.92), while adjusted incidence was 1.87/1,000,000 person-years (95% CI 1.11-3.16). In the full cohort, the first symptom of NMOSD was optic neuritis in 49.3% of the patients, followed by transverse myelitis (23.9%) and area postrema syndrome (10.4%). 62 patients relapsed in a mean follow-up of 2 years (0-7). 5 patients with less than 6 months of follow up had not relapsed. 55.2% of the patients were AQP4-IgG +, 14.9% AQP4-IgG -, and 29.9% unknown status. CONCLUSIONS: Although NMOSD prevalence is similar to other reports around the world, incidence is higher than in Caucasian populations. We believe that this high incidence is related to an increased awareness of the disease in the era of new NMOSD treatments. Recurrent disease is very frequent in our cohort.
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Neuromielite Óptica , Aquaporina 4 , Autoanticorpos , Feminino , Humanos , Imunoglobulina G , Masculino , México/epidemiologia , Neuromielite Óptica/diagnóstico , Neuromielite Óptica/epidemiologia , Estudos RetrospectivosRESUMO
Collagen is an extracellular matrix structural component that can regulate cellular processes through its interaction with the integrins, α1ß1, α2ß1, α10ß1, and α11ß1. Collagen-like proteins have been identified in a number of bacterial species. Here, we used Scl2 from Streptococcus pyogenes serotype M28 strain MGAS6274 as a backbone for the introduction of discrete integrin-binding sequences. The introduced sequences GLPGER, GFPGER, or GFPGEN did not affect triple helix stability of the Scl (Streptococcal collagen-like) protein. Using ELISA and surface plasmon resonance, we determined that Scl2(GLPGER) and Scl2(GFPGER) bound to recombinant human α1 and α2 I-domains in a metal ion-dependent manner and without a requirement for hydroxyproline. We predicted a novel and selective integrin-binding sequence, GFPGEN, through the use of computer modeling and demonstrated that Scl2(GFPGEN) shows specificity toward the α1 I-domain and does not bind the α2 I-domain. Using C2C12 cells, we determined that intact integrins interact with the modified Scl2 proteins with the same selectivity as recombinant I-domains. These modified Scl2 proteins also acted as cell attachment substrates for fibroblast, endothelial, and smooth muscle cells. However, the modified Scl2 proteins were unable to aggregate platelets. These results indicate that Scl2 is a suitable backbone for the introduction of mammalian integrin-binding sequences, and these sequences may be manipulated to individually target α1ß1 and α2ß1.
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Proteínas de Bactérias/química , Colágeno/química , Integrina alfa1/química , Integrina alfa2/química , Engenharia de Proteínas/métodos , Streptococcus pyogenes/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Adesão Celular , Linhagem Celular , Colágeno/genética , Colágeno/metabolismo , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Integrina alfa1/genética , Integrina alfa1/metabolismo , Integrina alfa2/genética , Integrina alfa2/metabolismo , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Streptococcus pyogenes/genéticaRESUMO
Hydrogen sulfide (H2S) is an endogenous gasotransmitter with potential therapeutic value for treating a range of disorders, such as ischemia-reperfusion injury resulting from a myocardial infarction or stroke. However, the medicinal delivery of H2S is hindered by its corrosive and toxic nature. In addition, small molecule H2S donors often generate other reactive and sulfur-containing species upon H2S release, leading to unwanted side effects. Here, we demonstrate that H2S release from biocompatible porous solids, namely metal-organic frameworks (MOFs), is a promising alternative strategy for H2S delivery under physiologically relevant conditions. In particular, through gas adsorption measurements and density functional theory calculations we establish that H2S binds strongly and reversibly within the tetrahedral pockets of the fumaric acid-derived framework MOF-801 and the mesaconic acid-derived framework Zr-mes, as well as the new itaconic acid-derived framework CORN-MOF-2. These features make all three frameworks among the best materials identified to date for the capture, storage, and delivery of H2S. In addition, these frameworks are non-toxic to HeLa cells and capable of releasing H2S under aqueous conditions, as confirmed by fluorescence assays. Last, a cellular ischemia-reperfusion injury model using H9c2 rat cardiomyoblast cells corroborates that H2S-loaded MOF-801 is capable of mitigating hypoxia-reoxygenation injury, likely due to the release of H2S. Overall, our findings suggest that H2S-loaded MOFs represent a new family of easily-handled solid sources of H2S that merit further investigation as therapeutic agents. In addition, our findings add Zr-mes and CORN-MOF-2 to the growing lexicon of biocompatible MOFs suitable for drug delivery.
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The fibrinogen (Fg) binding MSCRAMM Clumping factor A (ClfA) from Staphylococcus aureus interacts with the C-terminal region of the fibrinogen (Fg) gamma-chain. ClfA is the major virulence factor responsible for the observed clumping of S. aureus in blood plasma and has been implicated as a virulence factor in a mouse model of septic arthritis and in rabbit and rat models of infective endocarditis. We report here a high-resolution crystal structure of the ClfA ligand binding segment in complex with a synthetic peptide mimicking the binding site in Fg. The residues in Fg required for binding to ClfA are identified from this structure and from complementing biochemical studies. Furthermore, the platelet integrin alpha(IIb)beta(3) and ClfA bind to the same segment in the Fg gamma-chain but the two cellular binding proteins recognize different residues in the common targeted Fg segment. Based on these differences, we have identified peptides that selectively antagonize the ClfA-Fg interaction. The ClfA-Fg binding mechanism is a variant of the "Dock, Lock and Latch" mechanism previously described for the Staphylococcus epidermidis SdrG-Fg interaction. The structural insights gained from analyzing the ClfANFg peptide complex and identifications of peptides that selectively recognize ClfA but not alpha(IIb)beta(3) may allow the design of novel anti-staphylococcal agents. Our results also suggest that different MSCRAMMs with similar structural organization may have originated from a common ancestor but have evolved to accommodate specific ligand structures.
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Coagulase/metabolismo , Fibrinogênio/metabolismo , Modelos Moleculares , Infecções Estafilocócicas/tratamento farmacológico , Sítios de Ligação , Cristalografia por Raios X , Desenho de Fármacos , Peptídeos/síntese química , Peptídeos/farmacologia , Ligação Proteica/efeitos dos fármacos , Staphylococcus aureusRESUMO
Epilepsia partialis continua (EPC) has changed in its clinical and pathophysiological definition throughout time. Several etiologies have been described in addition to classic causes of EPC. The following case depicts a young woman who had a peculiar onset of epilepsy with a continuous visual aura becoming a form of chronic recurrent and non-progressive EPC. The patient was initially misdiagnosed as a non-neurological entity (assumed psychiatric in origin), but finally, an immune-mediated epilepsy was diagnosed, and EEG showed focal status epilepticus during evolution. Once the diagnosis was achieved and immune treatment was established, the patient is seizure free. Early identification of an immune basis in patients with epilepsy is important because immunotherapy can reverse the epileptogenic process and reduce the risk of chronic epilepsy. To date, this is the only case reported with EPC manifesting as a continuous visual aura associated with antiglutamic acid decarboxylase 65 (anti-GAD65) and anti-N-methyl-d-aspartate (anti-NMDA) antibodies.
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BACKGROUND: Surveys of cardiac pacing and implantable cardiovertor defibrillators (ICD) have been reported since 1969 and 1993 respectively. Increasing costs of medical technology, budget constraints and emergent new clinical indications prompted our committee to conduct the first survey of cardiac rhythm management and device implant patterns in Puerto Rico. METHOD: Clinical and demographic data were obtained for all cardiac devices sold and implanted from 2000 to 2006, through a joint agreement with official representatives of the 2 largest manufacturers and distributors of cardiac pacemakers and ICD in Puerto Rico. RESULTS: 13,854 cardiac devices were implanted from 2000 to 2006. The number of permanent pacemakers (PP) implanted per million population has varied from 430 in the year 2000 to 482 in the year 2006. A significant greater number of males received PP than females (P < .05). Yearly increases in implant rates for cardiac resynchronization therapy (CRT) and ICD were observed, mainly due to new emergent clinical indications, appropriate insurance coverage and availability of implanting electrophysiologists. CONCLUSIONS: Sales figures from PP and ICD manufacturers are a reliable system to calculate and analyze changes in cardiac device implant patterns. The rate of 482 PP per million population positions Puerto Rico as the third largest implant market in North and South America. This finding should be useful to insurance health providers since 76% of the implants are performed in patients over 65 years old. In the year 2006, Puerto Rico was the 10th largest implant market in the world with 67 CRT implanted per million population. A significant greater number of CRT and ICD were implanted in males than females. This gender difference has increased in spite of strict requirements to include more females in clinical trials and intensive, educational and awareness efforts conducted among physicians and patients. A summary of the current guidelines and clinical indications is provided to assist the physician in the selection of patients referred for cardiac rhythm management and implant procedures.
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Arritmias Cardíacas/terapia , Desfibriladores Implantáveis/estatística & dados numéricos , Marca-Passo Artificial/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Porto RicoRESUMO
BACKGROUND: Postoperative epidural fibrosis may contribute to between 5% to 60% of the poor surgical outcomes following decompressive surgery. Correlations have been reported between epidural scarring and radicular pain, poor surgical outcomes, and a lack of any form of surgical treatment. The use of spinal endoscopic adhesiolysis in recent years in the management of chronic refractory low back and lower extremity pain has been described. METHODS: A prospective, randomized, double-blind trial was conducted to determine the outcome of spinal endoscopic adhesiolysis to reduce pain and improve function and psychological status in patients with chronic refractory low back and lower extremity pain. A total of 83 patients were evaluated, with 33 patients in Group I and 50 patients in Group II. Group I served as the control, with endoscopy into the sacral level without adhesiolysis, followed by injection of local anesthetic and steroid. Group II received spinal endoscopic adhesiolysis, followed by injection of local anesthetic and steroid. RESULTS: Among the 50 patients in the treatment group receiving spinal endoscopic adhesiolysis, significant improvement without adverse effects was shown in 80% at 3 months, 56% at 6 months, and 48% at 12 months. The control group showed improvement in 33% of the patients at one month and none thereafter. Based on the definition that less than 6 months of relief is considered short-term and longer than 6 months of relief is considered long-term, a significant number of patients obtained long-term relief with improvement in pain, functional status, and psychological status. CONCLUSION: Spinal endoscopic adhesiolysis with targeted delivery of local anesthetic and steroid is an effective treatment in a significant number of patients with chronic low back and lower extremity pain without major adverse effects.
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BACKGROUND: Psychological disorders may be associated with poor pain related treatment outcomes. However, there may be limitations with studies evaluating the relationship between pain and psychopathology. OBJECTIVE: To assess the reliability of psychological evaluations in interventional pain management by MCMI-III(R) and P-3(R). STUDY DESIGN: Prospective evaluation of consecutive patients in an interventional pain management center. METHODS: Patients were evaluated using a DSM-IV-TR(R) questionnaire with a physician interview as an integral part of their comprehensive evaluation. In addition, all the patients participating in this study also underwent psychological evaluation with MCMI-III and P-3. A positive diagnosis of major depression or generalized anxiety disorder based on DSM-IV-TR criteria was considered as the criterion standard. All of the patients presented for treatment of chronic pain. The data based on the criterion standard were compared with results of the diagnostic impression from the MCMI-III and the P-3 evaluation utilizing criteria for average, and above average, patient pain scores. RESULTS: Major depression was diagnosed in a total of 59 of 100 patients using DSM-IV-TR criteria, in 32 patients based on MCMI-III criteria, and in 55 patients based on P-3 evaluations utilizing average pain patient criteria. Generalized anxiety disorder was diagnosed in 55 patients by means of DSM-IV-TR, 45 patients by MCMI-III, and 55 patients by P-3 Profile utilizing average pain patient scores. The specificity of MCMI-III was 100% with a sensitivity of 54% for diagnosis of depression; whereas it was 78% specificity and sensitivity for P-3, with average pain patient scores. For generalized anxiety disorder, specificity of MCMI-III was 89% with a sensitivity of 73% compared to specificity of 80% and sensitivity of 84% for average pain patient scores for P-3. CONCLUSION: MCMI-III and P-3 are highly specific in diagnosing depression and generalized anxiety disorder, with variable sensitivity. A DSM-IV-TR questionnaire evaluation incorporated into the pain management questionnaire, along with a short clinical interview, is a reliable means of assessing depression and anxiety in patients suffering with chronic pain.
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Epidural steroid injections are the most commonly used procedures to manage chronic low back pain in interventional pain management settings. The overall effectiveness of epidural steroid injections has been highly variable, and in the role has not been evaluated in patients discographically evaluated. One hundred consecutive patients, without evidence of disc herniation or radiculitis, who had failed to respond to conservative management with physical therapy, chiropractic and/or medical therapy, underwent discography utilizing strict criteria of concordant pain, and negative adjacent discs, after being judged to be negative for facet joint and/or sacroiliac joint pain utilizing comparative local anesthetic blocks. Any other type of response was considered negative. This study included 62 patients, who underwent caudal epidural steroid injections with Sarapin. They included Group I, comprised of 45 of 55 patients negative on provocative discography; and Group II, with 17 of 45 patients with positive provocative discography. Results showed that there was significant improvement in patients receiving caudal epidural injections, with a decrease in pain associated with improved physical, functional, and mental status; decreased narcotic intake, and increased return to work. The study showed that at 1 month, 100% of the patients evaluated showed significant improvement in both groups; this declined to 86% at 3 months in Group I, but remained at 100% in Group II, declining to 60% and 64% at 6 months in Group I and Group II, respectfully, with administration of one to three injections. Analysis with one to three injections, which included all (62) patients showed significant relief in 71% and 65% of the patients at 1 month, in 67% and 65% at 3 months, and in 47% and 41% at 6 months, in Group I and Group II, respectively. In conclusion, caudal epidural injections with or without steroids is an effective modality of treatment in managing chronic, persistent low back pain failing to respond to conservative modalities of treatments, in patients negative for facet joint and sacroiliac joint pain, whether positive or negative, on evaluation with provocative discography.
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Many commissions and groups throughout the world have proposed clinical guidelines on the management of low back pain, spinal pain, and chronic pain. Practice guidelines are systematically developed statements to assist the practitioner and patient decisions about appropriate healthcare for specific clinical circumstances. The American Society of Interventional Pain Physicians developed practice guidelines for interventional techniques which are professional practice recommendations for practices for prevention, diagnosis and treatment of acute and chronic painful disorders, and in some cases, disability management. The effectiveness of so-called evidence-based guidelines has not proven. This study was designed to evaluate a total of 300 patients with 100 randomized patients seen in the month of January 1999, 2000 and 2001, in one private pain management practice in a non-university setting. The study was retrospective for 1999 and 2000, whereas it was prospective for 2001. The results showed that there were no significant differences in patient demographics or their psychological status. The results consistently showed decrease in number of visits from 1999 to 2000 and 2001 with 5.5 +/- 0.18, 5.1 +/- 0.17, and 4.3 +/- 0.15 respectively. The average expenditure also decreased from per visit of $872 in 1999 to $891 in 2000, to $810 to 2001. further, the average expenditure per year also decreased as expected due to decrease in frequency of visits, as well as the average expenditure per visit from $4751 +/- $231 in 1999 to $4505 +/- $214 in 2000 and to $3514 +/- $193 in 2001 even without consideration of inflation. Thus, it is concluded that guidelines describing the interventional techniques in the management of chronic pain are effective in reducing the cost and frequency of visits with improvement or at least maintenance of similar outcomes, physician decision making abilities, and patient preferences.
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BACKGROUND: Lumbar facet (zygapophysial) joints have been implicated as the source of chronic pain in 15% to 45% of patients with chronic low back pain. Diagnosis may be confounded by false-positive results with a single diagnostic block and administration of anxiolytics and narcotics prior to or during the diagnostic facet joint blocks. OBJECTIVE: To evaluate the effect of midazolam and fentanyl on the diagnostic validity of of lumbar facet joint pain. STUDY DESIGN: Randomized, prospective, double-blind, placebo-controlled evaluation. METHODS: The design consisted of a placebo group receiving sodium chloride solution and two experimental groups receiving either midazolam or fentanyl. The patients included in the study were diagnosed with facet joint pain with controlled comparative local anesthetic blocks of medial branches or L5 dorsal rami. They had been treated with lumbar facet joint nerve blocks with good pain relief, and were presenting for repeat treatment after a period of symptom relief. The study was undertaken in an interventional pain management practice. OUTCOME MEASURES: Outcomes were assessed at baseline and after the administration of 1 of the 3 solutions (Group I, sodium chloride solution; Group II, midazolam; or Group III, fentanyl). Outcome measures included numeric pain scale, proportion of pain relief, and ability to perform prior painful movements. RESULTS: Pain relief of > or =80% was noted in 2% of the patients in Group I, 5% of the patients in Group II, and 7% in Group III. Pain relief of > or =50% was noted in 7% of the patients in Group I, 5% of the patients in Group II, and 13% of the patients in Group III. There were no significant differences among the groups. CONCLUSION: The administration of sedation with midazolam or fentanyl is a confounding factor in the diagnosis of lumbar facet joint pain in patients with chronic low back pain. However, this study suggests that if strict criteria including pain relief and ability to perform prior painful movements is used as the standard for evaluating the effect of controlled local anesthetic blocks, the diagnostic validity of lumbar facet joint nerve blocks may be preserved.
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BACKGROUND: Chronic, refractory low back pain is a common problem. Percutaneous adhesiolysis with hypertonic saline neurolysis was described in the management of chronic refractory low back pain, non-responsive to conservative modalities of management. OBJECTIVE: To determine the ability of percutaneous adhesiolysis and hypertonic saline administration to reduce pain and improve functional and psychological status in patients with chronic low back pain. DESIGN: Randomized, double-blind, controlled trial. METHODS: A total of 75 patients were studied, with 25 patients in each group. Three types of interventions were included, with Group I serving as control with catheterization without adhesiolysis, followed by injection of local anesthetic, normal saline, and steroid. Group II consisted of catheterization and adhesiolysis, followed by injection of local anesthetic, normal saline, and steroid. Group III consisted of adhesiolysis followed by injection of local anesthetic, hypertonic saline, and steroid. Statistical analysis incorporated intent-to-treat analysis. OUTCOME MEASURES: Visual Analogue Scale pain scores, Oswestry Disability Index, work status, opioid intake, range of motion measurement, and P-3 (R). Significant pain relief was defined as average relief of 50% or greater. RESULTS: Significant improvement was seen in patients in Group II and III, at 3 months, 6 months, and 12 months, compared to baseline measurements, as well as compared to Group I without adhesiolysis. Seventy-two percent of patients in Group III (adhesiolysis and hypertonic neurolysis), 60% of patients in Group II (adhesiolysis only), compared to 0% in Group I (control) showed significant improvement at 12-month follow up. The average number of treatments for one year were 2.76 in Group II and 2.16 in Group III. Duration of significant relief with the first procedure was 2.8 +/- 1.49 months in Group II and 3.8 +/- 3.37 months in Group III. CONCLUSION: Percutaneous adhesiolysis, with or without hypertonic saline neurolysis, is an effective treatment for chronic low back pain.
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Epidural adhesiolysis with spinal endoscopy is an emerging interventional pain management technique in managing chronic refractory low back and lower extremity pain. However, there is a lack of significant data demonstrating the effectiveness of spinal endoscopic adhesiolysis. This randomized, double-blind controlled trial was undertaken to determine the ability of spinal endoscopic adhesiolysis to reduce pain and improve functional and psychological status. The study was performed in an interventional pain management practice, a specialty referral center, in a private practice setting. This trial extended from January 2002 to December 2002. However, only the patients with 6-month follow-up were included. Any relief of less than 6 months was considered as short-term and 6-months or longer was considered as long-term. All the patients with chronic low back pain of at least 6 months and having failed conservative modalities of management, including fluoroscopically directed epidural steroid injections and percutaneous adhesiolysis, were included. Patient assignment was by randomized selection from all eligible subjects. Two types of interventions were included with Group I serving as the control with endoscopy to the sacral level without adhesiolysis, followed by injection of local anesthetic and steroid. Group II consisted of spinal endoscopy and appropriate adhesiolysis, followed by injection of local anesthetic and steroid. Outcome measures were focused to evaluate and demonstrate a clinically significant difference between the treated patients and those patients randomized to the control group in multiple parameters of pain, functional status, psychological, and behavioral status. Overall, 13 of 23 patients (57%) showed significant improvement without adverse events. Based on the definition that less than 6 months of relief is considered as short-term and longer than 6 months is considered as long-term, a significant number of patients obtained long-term relief. The results showed significant improvement in patients undergoing spinal endoscopic adhesiolysis at 1-month, 3-months, and 6-months, compared to baseline measurements, as well as compared to the control group without adhesiolysis. Spinal endoscopic adhesiolysis with targeted injection of local anesthetic and steroid, is an effective treatment in a significant number of patients without major adverse effects at 6-month follow-up.
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The major barriers to the clinical success of orthopedic and dental implants are poor integration of fixtures with bone tissue and biomaterial-associated infections. Although multifunctional device coatings have long been considered a promising strategy, their development is hindered by difficulties in integrating biocompatibility, anti-infective activity and antithrombotic properties within a single grafting agent. In this study, we used cell adhesion assays and confocal microscopy of primary murine osteoblasts and human osteoblast cell lines MG-63 and Saos-2 to demonstrate that a streptococcal collagen-like protein engineered to display the α1 and α2 integrin recognition sequences enhances osteoblast adhesion and spreading on titanium fixtures. By measuring calcium deposition and alkaline phosphatase activity, we also showed that selective activation of α2ß1 integrin induces osteoblast differentiation, osteoid formation and mineralization. Moreover, cell adhesion assays and scanning electron microscopy of clinical isolates Staphylococcus aureus Philips and Staphylococcus epidermidis 9491 indicated that streptococcal collagen-mimetic proteins inhibit bacterial colonization and biofilm formation irrespective of their interaction with integrins. Given that streptococcal collagenous substrates neither interact with platelets nor trigger a strong immune response, this novel bioactive coating appears to have desirable multifaceted properties with promising translational applications.