Biocompatibility analysis and chemical characterization of Mn-doped hydroxyapatite.

The present work studies the effect of Mn doping on the crystalline structure of the Hap synthesized by the hydrothermal method at 200 °C for 24 h, from Ca(OH)2 and (NH4)2HPO4, incorporating MnCl2 to 0.1, 0.5, 1.0, 1.5 and 2.0 %wt of Mn concentrations. Samples were characterized by the X-Ray Diffraction technique, which revealed the diffraction peaks that corresponded to the hexagonal and monoclinic phase of the Hap; it was observed that the average size of crystallite decreased from 23.67 to 22.69 nm as the concentration of Mn increased. TEM shows that in all samples, there are two distributions of particle sizes; one corresponds to nanorods with several tens of nanometers in length, and the other in which the diameter and length are very close. FTIR analysis revealed absorption bands corresponding to the PO4-3 and OH- groups characteristic of the Hap. It was possible to establish a substitution mechanism between the Mn and the ions of Ca+2 of the Hap. From the Alamar blue test, a cell viability of 86.88% ± 5 corresponding to the sample of Hap at 1.5 %wt Mn was obtained, considered non-cytotoxic according to ISO 10993-5. It also evaluated and demonstrated the good osteoinductive properties of the materials, which were verified by histology and immunofluorescence expression of osteogenic markers. Adhesion, viability, biocompatibility and osteoinductive properties, make these materials candidates for future applications in bone tissue engineering with likely uses in regenerative medicine.

Cytogenomic characterization of small supernumerary marker chromosomes in patients with pigmentary mosaicism.

Introduction: The combination of gene content on the marker chromosome, chromosomal origin, level of mosaicism, origin mechanism (chromothripsis), and uniparental disomy can influence the final characterization of sSMCs. Several chromosomal aberrations, including sSMCs, have been observed in 30%-60% of patients with pigmentary mosaicism, and in more than 80%, chromosomal abnormalities are present in the mosaic state. In patients with pigmentary mosaicism the most representative chromosomes involved in sSMCs are 3, 5, 6, 9, 10, 13, 15, 18, 20, and X. In this study, we included the complete clinical, cytogenetic, and molecular characterization of seven patients with pigmentary mosaicism associated with the presence of SMCs of different chromosomal origins. Methods: The patients were diagnosed by the Genetics and Dermatology Department of three different hospitals. Cytogenetic and FISH analyses were performed on peripheral blood, light skin, and dark skin. FISH analysis was performed using different probes, depending on the marker chromosome description. Different array analysis was performed. Results: To date, of the seven cases studied, the chromosomal origins of six were successfully identified by FISH or array analysis. The chromosomes involved in SMCs were 6, 9, 15, and 18, X. The most frequently found was the centric minute structure. Discussion: To date, this group of seven patients constitutes the largest clinical and cytogenetically finely described study of cases with pigmentary mosaicism associated with sSMCs. Undoubtedly, analysis of the two skin types is a fundamental part of our study, as numerical differences may occur in the cell lines found in each skin type. The knowledge generated in this study will help delineate a very heterogeneous entity more accurately, and in the future, analyzing more patients with PM will likely establish a more definite association with the presence of this genetic alteration.

Synthesis, characterization and thermoluminescence properties of MgB4O7 phosphor co-doped with Tm and Dy.

The luminescent and dosimetric properties of the MgB4O7 phosphor co-doped with Tm and Dy ions (MgB4O7:Tm,Dy) obtained by the solution combustion technique were investigated. With the prepared material, sintered dosimeters in pellet form were made. The MgB4O7 dosimeters doped with Tm and Dy with 0.25 and 0.10 mol% respectively and sintered at 1223 K for 3 h showed a sensitivity almost 11 times greater than the sensitivity of the TLD-100 commercial dosimeter. The TL response as a function of the gamma dose showed linearity up to 50 Gy followed by a supralinearity region and, above 500 Gy, the saturation region of the electron traps is reached. The fading of the main TL peak was negligible in the first five days after irradiation reaching 13% after 60 days and the lower detection limit was 43 µGy. The kinetic parameters were determined using the deconvolution method revealing general and second order kinetics. The morphology, crystallography and photoluminescence of the prepared phosphor samples are also reported.

Use of a Pfannenstiel incision in minimally invasive colorectal cancer surgery is associated with a lower risk of wound complications.

BACKGROUND: The Pfannenstiel incision, widely used in gynecological surgery, has been reported to be associated with lower rates of wound complications than midline incisions in open surgery. However, its effect on wound complications in minimally invasive surgery (MIS) is not well understood. We hypothesize that use of a Pfannenstiel incision in MIS colorectal cancer resections would be associated with fewer short-term wound complication rates. METHODS: A retrospective cohort study was performed on 171 patients who had undergone MIS colorectal cancer surgery requiring a specimen extraction/hand-access site, divided into a Pfannenstiel and a midline group depending on the type of incision used. Wound complications compared included disruption, infection, dehiscence, evisceration, and fistula formation. The Mann-Whitney U and Fisher's exact tests were used to analyze differences in risk factors between the groups. Logistic regression was performed to determine factors associated with prevention of wound complications. RESULTS: Patients in the Pfannenstiel group had significantly lower rates of wound disruption (0 vs. 13%, p = 0.02), superficial surgical site infection (7 vs. 22%, p = 0.03), and overall wound complications (13 vs. 30%, p = 0.04). Using multivariate logistic regression, Pfannenstiel incisions and colon rather than rectal resections were significant predictors of prevention of wound complications. CONCLUSIONS: The use of a Pfannenstiel incision in MIS colorectal cancer resections is associated with a decreased risk of short-term wound complications.

Are intravitreal injections essential during the COVID-19 pandemic? Global preferred practice patterns and practical recommendations.

Tertiary outpatient ophthalmology clinics are high-risk environments for COVID-19 transmission, especially retina clinics, where regular follow-up is needed for elderly patients with multiple comorbidities. Intravitreal injection therapy (IVT) for chronic macular diseases, is one of the most common procedures performed, associated with a significant burden of care because of the vigorous treatment regimen associated with multiple investigations. While minimizing the risk of COVID-19 infection transmission is a priority, this must be balanced against the continued provision of sight-saving ophthalmic care to patients at risk of permanent vision loss. This review aims to give evidence-based guidelines on managing IVT during the COVID-19 pandemic in common macular diseases such as age-related macular degeneration, diabetic macula edema and retinal vascular disease and to report on how the COVID-19 pandemic has affected IVT practices worldwide.To illustrate some real-world examples, 18 participants in the International Retina Collaborative, from 15 countries and across four continents, were surveyed regarding pre- and during- COVID-19 pandemic IVT practices in tertiary ophthalmic centers. The majority of centers reported a reduction in the number of appointments to reduce the risk of the spread of COVID-19 with varying changes to their IVT regimen to treat various macula diseases. Due to the constantly evolving nature of the COVID-19 pandemic, and the uncertainty about the normal resumption of health services, we suggest that new solutions for eye healthcare provision, like telemedicine, may be adopted in the future when we consider new long-term adaptations required to cope with the COVID-19 pandemic.

Pigmentary mosaicism as a recurrent clinical manifestation in three new patients with mosaic trisomy 12 diagnosed postnatally: cases report and literature review.

BACKGROUND: To date, only twenty-one cases diagnosed postnatally with mosaic trisomy 12 have been reported. The most frequent phenotypic manifestations are developmental delay, dysmorphic facial features, congenital heart defects, digital alterations, and pigmentary disorders. In the present report, detailed clinical and genetic profiles of three unrelated new patients with mosaic trisomy 12 are described and compared with previously reported cases. CASE PRESENTATION: In the present report, we include the clinical, cytogenetic, and molecular description of three Mexican patients diagnosed postnatally with mosaic trisomy 12. At phenotypic level, the three patients present with developmental delay, dysmorphic facial features, congenital heart defects and skin pigmentary anomalies. Particularly, patient 1 showed unique eye alterations as bilateral distichiasis, triple rows of upper lashes, and digital abnormalities. In patient 2 redundant skin, severe hearing loss, and hypotonia were observed, and patient 3 presented with hypertelorism and telecanthus. Hyperpigmentation with disseminated pigmentary anomalies is a common trait in all of them. The cytogenetic study was carried out under the strict criteria of analysis, screening 50-100 metaphases from three different tissues, showing trisomy 12 mosaicism in at least one of the three different tissues analyzed. With SNParray, the presence of low-level mosaic copy number variants not previously detected by cytogenetics, and uniparental disomy of chromosome 12, was excluded. STR markers allowed to confirm the absence of uniparental disomy as well as to know the parental origin of supernumerary chromosome 12. CONCLUSIONS: The detailed clinical, cytogenetic, and molecular description of these three new patients, contributes with relevant information to delineate more accurately a group of patients that show a heterogeneous phenotype, although sharing the same chromosomal alteration. The possibility of detecting mosaic trisomy 12 is directly associated with the sensitivity of the methodology applied to reveal the low-level chromosomal mosaicism, as well as with the possibility to perform the analysis in a suitable tissue.

A novel synthesis method to produce silver-doped CeO2 nanotubes based on Ag nanowire templates.

Silver nanowires were used as templates to synthesize silver-doped CeO(2) (Ag-CeO(2)) nanotubes by the precipitation method. The precipitated solid was dried at 100 °C for 24 h and calcined at 500 °C for 5 h. A TEM, HRTEM, LV-SEM and XRD study was carried out to determine the micro and nanostructural characteristics of the samples. LV-SEM analysis allowed us to observe microtubular empty structures constituted by Ce, O and Ag as indicated by EDS. These tubular structures, with an external diameter from 120 to 280 nm and an internal diameter from 40 to 80 nm, were mainly composed of 11 nm ceria nanoparticles. This kind of structures was obtained when CeO(2) nanoparticles covered the Ag nanowires during the synthesis. Due to the presence of ammonium hydroxide used during the synthesis, a fraction of the silver nanowire reacts and Ag atoms begin to migrate outside the ceria microtube. When the sintering process is applied, the Kirkendall effect can occur. So, out-diffusion of the remnant Ag through the interface is faster than the in-diffusion of the shell material (CeO(2)), which eventually results in a coaxial nanotube on completion of the non-equilibrium interdiffusion, leaving the central core completely empty, driving the formation of hollow tubular Ag-CeO(2) structures as a result.

Luminescence and kinetics parameters of high sensitivity MgB4O7 phosphor co-doped with Tm and Dy.

This work reports the luminescence and kinetics parameters of high sensitivity MgB4O7 phosphor co-doped with Tm and Dy ions (MgB4O7:Tm,Dy) obtained by the solution combustion technique. With the obtained material, sintered dosimeters in form of discs were made and subjected to 1223 K for 3 h and exposed to gamma radiation from a60Co source. It was found that these dosimeters show a sensitivity approximately 10 times higher than that shown by the commercial dosimeter TLD-100 (LiF:Mg,Ti). The kinetic parameters from three samples with different concentration of dopants were determined using the initial rise, peak shape and deconvolution methods. Initial rise and peak shape methods showed lower values than those found by the deconvolution method for the main peak (Peak 1). MgB4O7:Tm, Dy shows a wide linearity interval of TL response with respect to gamma dose and low coefficient of variability (1.5%). These results suggest that this new high sensitivity phosphor could be a promising material to be used in clinical dosimetry.

[Adherence to pulmonary rehabilitation: An exploratory review]. / La adherencia a los tratamientos de rehabilitación pulmonar: revisión exploratoria.

Currently, several studies have identified low adherence to pulmonary rehabilitation in patients with COPD, despite the positive effects of the treatment. Patient adherence to pulmonary rehabilitation is affected by factors such as the absence of family support, and the presence of multiple comorbidities, respiratory distress, anxiety and depression. Given that there is no conclusive evidence about which of these factors are most influential in determining adherence to pulmonary rehabilitation in patients with COPD, we conducted this scoping review to analyse the available evidence on the factors influencing the adherence of patients with COPD to pulmonary rehabilitation programs (PRP). A wide literature search was carried out in Medline, Ovid, Science Direct, EMBASE, EBSCO and ISI-web of science, with prior definition of the selection criteria that included the factors associated with healthcare and adherence in patients with COPD in PRP. We used the adherence model proposed by the WHO as a conceptual framework. As a significant result, we found that factors in the dimension of illness (40%) and patient (30%) were the most frequently found dimensions in the studies, revealing that the design of pulmonary rehabilitation programs must take into account the specific needs of the patient. Further studies are needed to establish barriers and facilitators of adherence among COPD patients to PRP in the Colombian setting.

Effect of sintering temperature on sensitivity of MgB4O7:Tm,Ag obtained by the solution combustion method.

Borates are appropriate TL materials for radiation dosimetry, because of their equivalence with tissue. Magnesium borate is a tissue equivalent material and its most important advantage over lithium borate, is that this material is insoluble in water. In this work the effect of sintering temperature on the sensitivity of magnesium borate obtained by the solution combustion technique is presented. The results showed that the material doped with Tm and Ag, subjected to 1223 K, for 3 h, had a sensitivity between two and four times higher than that of the commercial dosimeter TLD-100 making it highly appropriate for applications in clinical dosimetry.

Molecular prognosticators of complex karyotype soft tissue sarcoma outcome: a tissue microarray-based study.

BACKGROUND: Molecular markers are currently being utilized as sensitive prognosticators of cancer patient outcome. We sought to identify prognostic biomarkers for complex karyotype soft tissue sarcoma (STS). MATERIALS AND METHODS: A large (n = 205) clinically annotated tissue microarray (TMA) was constructed and immunostained for several tumor-related markers. Staining was scored via an automated Ariol image analysis system; data were statistically analyzed to evaluate the correlation of clinicopathological and molecular variables with overall survival (OS) and local recurrence. RESULTS: Multivariable analysis identified older age [hazard ratio (HR) 1.62, P < 0.0001], nonextremity location (HR 2.95, P = 0.001), high tumor grade (HR 2.5, P = 0.02), and increased matrix metalloproteinase (MMP) 2 expression (HR 1.74, P = 0.04) as predictors for poor OS. Similarly, older age (HR 1.51, P = 0.008), nonextremity location (HR 4.09, P = 0.001), and increased MMP2 expression (HR 6.28, P = 0.006) were all found to correlate with shorter local recurrence-free interval. High nuclear p53 expression was associated with shorter STS local recurrence-free interval, with a trend toward significance. CONCLUSIONS: Data presented indicate that a clinically annotated TMA can be utilized to identify STS-related prognostic markers. Specifically, MMP2 and nuclear p53 should be further evaluated for their potential inclusion in complex karyotype STS staging systems.

Postoperative nomogram for survival of patients with retroperitoneal sarcoma treated with curative intent.

BACKGROUND: Current American Joint Committee on Cancer retroperitoneal sarcoma (RPS) staging is not representative of patients with RPS specifically and has limited discriminative power. Our objective was to develop a RPS disease-specific nomogram capable of stratifying patients based on probability of overall survival (OS) after resection. PATIENTS AND METHODS: In all, 1118 RPS patients were evaluated at our institution (1996-2006). Patients with resectable, nonmetastatic disease were selected (n = 343) and baseline, treatment and outcome variables were retrieved. A nomogram was created and its performance was evaluated by calculating its discrimination (concordance index) and calibration and by subsequent internal validation. RESULTS: Median follow-up and OS were 50 and 59 months, respectively. Independent predictors of OS were included in the nomogram: age (> or = 65), tumor size (> or = 15 cm), type of presentation (primary versus recurrent), multifocality, completeness of resection and histology. The concordance index was 0.73 [95% confidence interval (CI) 0.71-0.75] and the calibration was excellent, with all observed outcomes within the 95% CI of each predicted survival probability. CONCLUSIONS: A RPS-specific postoperative nomogram was developed. It improves RPS staging by allowing a more dynamic and robust disease-specific risk stratification. This prognostic tool can help in patient counseling and for selection of high-risk patients that may benefit from adjuvant therapies or inclusion into clinical trials.

Dosimetric properties of Li2B4O7:Cu,Ag,P solid detector.

This work presents results obtained following the preparation of lithium borate by the chemical reaction between lithium carbonate (Li2CO3) and boric acid (H3BO3), doping the host salt of lithium borate (Li2B4O7) with ions of copper, silver and phosphorus. With the obtained material dosimeters were produced in sintered pellet form which were exposed by gamma radiation that emitted from 60Co source. The highest sensitivity was found for the sample of Li2B4O7:Cu,Ag,P (in pellet form) with 0.45, 0.45 and 12 mol% of Cu, Ag and P, respectively, subjected to a thermal treatment at 1123 K during 2 h. The TL response shows linearity in the dose range from 0.005 to 100 Gy. The lower detection limit (LDL) was equal to 6.10 µGy. The fading was found to be 3% in the first ten days and 9% at the end of thirty days. The repeatability of TL measurements for twenty cycles, showed a variability coefficient equal to 4.15%. The glow curve shape of Li2B4O7:Cu,Ag,P sintered pellet shows two peaks with general-kinetics order. This new material could be appropriate for dosimetry in clinical radiation applications.

Genetic and clinical characterization of 73 Pigmentary Mosaicism patients: revealing the genetic basis of clinical manifestations.

BACKGROUND: Pigmentary mosaicism constitutes a heterogeneous group of skin pigmentation alterations associated with multisystem involvement. The aim of this study was to establish a complete cytogenetic and molecular characterization of PM patients, emphasizing on searching for possible low chromosomal mosaicism and on establishing an accurate genotype-phenotype correlation. RESULTS: A total of 73 patients were included (3 months to 18 years of age), 52% male and 48% female. Observed in 69 (95%) patients, the most frequent pattern of pigmentation was fine and whorled BL, which was associated with disseminated skin extent in 41 (59%) patients. Central nervous system (84%) alterations were the most frequent observed in the group of patients, followed by the musculoskeletal (53%) and ophthalmologic (27%) alterations. Considering the pattern of pigmentation, no significant differences in association with skin extent or extracutaneous manifestations were detected. Following a strict cytogenetic analysis strategy, screening metaphases from three different tissues (peripheral blood, hyperpigmented and hypopigmented skin) we found that 23/73 patients had chromosomal abnormalities classified as follows: 1) Mosaic with 2 or more different cell lines with structural alterations n = 19; 2) Polyploidy (mosaic) n = 1 and 3) Alterations in all cells in three different tissues n = 3. SNP array, array CGH and FISH were useful for the complete characterization of the chromosomal aberrations, for the detection of microdeletions in patients with normal karyotype but with strong clinical suspicious of chromosomal alteration, and for a better establishment of genotype-phenotype correlation. In 2 patients we found genes associated with some of the extracutaneous manifestations (SHH, MNX1, PPP2R2C). CONCLUSIONS: This group of 73 patients finely described is the largest series of patients with pigmentary mosaicism reported worldwide. As we showed in this study, the followed analysis strategy allowed the detection of cytogenetic and molecular abnormalities, and made possible the establishment of genotype-phenotype associations in some patients. An important limitation of our study was the analysis of fibroblasts cultures instead of melanocytes and keratinocytes. In some cases the direct molecular DNA analysis of skin biopsy could be another choice.

Resectable well-differentiated versus dedifferentiated liposarcomas: two different diseases possibly requiring different treatment approaches.

BACKGROUND: Division of retroperitoneal liposarcoma (RPLS) into well-differentiated (WD) and dedifferentiated (DD) subtypes is established; however, WD and DD are usually treated similarly. We hypothesized that WD and DD have distinct biological behaviors mandating different treatments. METHODS: A prospective sarcoma database identified all primary/recurrent RPLS treated between 1996 and 2007: 77 DD (52%) and 58 WD (39.2%) patients were analyzed for recurrence rate, recurrence free survival (RFS), and overall survival (OS). RESULTS: At presentation, WD were mostly primary whereas DD were mostly recurrent (75.9% versus 58.4%; p = 0.04). A significant proportion of DD (37.7%) received chemotherapy compared to WD (1.7%; p < 0.0001). Multivisceral resection was more common in DD versus WD (45.5% versus 31%; p = 0.01). Gross total resection rates were equivalent (WD: 86.2%; DD: 85.7%). Overall and local recurrence were higher in DD versus WD (82.2% versus 50% and 71.2% versus 46.3%; p < 0.0001). Only 3.7% WD recurred as high grade metastatic disease. Median time to recurrence was 55.5 months in WD versus 13.5 months in DD (p < 0.0001). RFS and OS (1, 2, and 5 year) were higher in WD than DD (80.3% versus 55.9%; 65.1% versus 34.1%; 41.9% versus 7.8%; p < 0.0001) and (98% versus 88.1%; 95.6% versus 71.9%; 92.1% versus 36.5%; p < 0.0001) respectively. CONCLUSION: WD and DD have distinct biological behaviors. Gross total resection is achievable in most WD; unlike DD, high-grade recurrence is uncommon. Treatment should therefore reflect these biologic differences by maximizing survivorship while avoiding unnecessarily extensive multivisceral resection. SYNOPSIS: The biological behaviors of well-differentiated and dedifferentiated liposarcomas differ significantly. This article presents outcomes of two different surgical approaches that were implemented at the UTMDACC, treating these tumors as different disease entities.

New perspectives for staging and prognosis in soft tissue sarcoma.

BACKGROUND: Data suggest that the current American Joint Committee on Cancer (AJCC) soft tissue sarcoma (STS) staging criteria merit further evaluation. We sought to identify and validate factors as enhanced descriptors of STS clinical behavior. METHODS: Prospectively accrued data were analyzed for 1,091 AJCC stage I to III primary STS patients who had complete macroscopic resection at our institution from 1996 to 2007. Study factors were examined by univariable and multivariable analyses to identify independent prognostic factors for disease related mortality and overall survival (OS). RESULTS: In contrast to the current AJCC STS staging system, which stratifies size into T1 (5 cm) groups, we demonstrated three distinct cohorts (P < 0.0001): T1 (15 cm; OS 52%). A two-category system of histologic grade was demonstrably as informative as the current four histologic grade AJCC system. A multivariable Cox proportional hazard model identified tumor size (5 to 15 cm vs. 15 cm vs.

Dosimetric properties of α-Al2O3: Tm+PTFE phosphor.

A new α-Al2O3 doped with Tm3+ ions was obtained by combustion method; doped α-Al2O3 in the powder form was mixed with polytetrafluoroethylene resin (PTFE) to obtain dosimeters in pellet form, in order to be used as radiation dosimeter. The glow curve, linearity, lower detection limit, repeatability and fading, were studied. The kinetic parameters were determined by deconvolution method. Morphological characteristics were studied by low vacuum scanning electron microscopy and X-ray diffraction. Results showed that α-Al2O3+PTFE obtained is a promising material to radiation dosimetry.

Wet chemical synthesis of nanocrystalline hydroxyapatite flakes: effect of pH and sintering temperature on structural and morphological properties.

Wet chemical synthesis of hydroxyapatite (HAp) nanostructures was carried out with different solution pH values (9, 10 and 11) and sintering temperatures (300°C, 500°C, 700°C and 900°C). The effects of pH and sintering temperature on the structural and morphological properties of nanocrystalline HAp powders were presented. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were performed to obtain the crystalline structure, chemical composition, morphology and particle size of the HAp powders. The TEM analysis is used in order to observe the rod- and flake-like HAp structures. XRD confirms the presence of both HAp hexagonal and monetite phases, although the monetite phase was less abundant in the resultant powders. Increase in pH reduced the monetite phase and enhanced Ca/P ratio from 1.7 to 1.83. Additionally, an increment in sintering temperature increased the crystallite size from 20 to 56 nm. The SEM analysis revealed the formation of semi-spherical and flake-like HAp structures with preferential flake morphology. An increase in pH and sintering temperature resulted in the growth and coalescence of crystals resulting in a porous capsular morphology. The FTIR analysis confirmed the reduction of carbonate stretching modes with an increase in pH and H-O-H antisymmetric stretching mode is eliminated for powders sintered at 900°C confirming the formation of stable and porous HAp powders.

La adherencia a los tratamientos de rehabilitación pulmonar: revisión exploratoria / Adherence to pulmonary rehabilitation: An exploratory review

En la actualidad diversos estudios han identificado una baja adherencia al tratamiento de rehabilitación pulmonar en pacientes con EPOC, a pesar de los efectos positivos que se obtienen con el tratamiento; factores como la ausencia de soporte familiar, las múltiples comorbilidades, la dificultad respiratoria, la ansiedad y la depresión afectan la adherencia de los pacientes a la rehabilitación pulmonar. Dado que no existe evidencia concluyente acerca de cuáles de estos factores son más determinantes en la adherencia a la rehabilitación pulmonar de los pacientes con EPOC, se decidió realizar esta revisión exploratoria (scoping review) con el objetivo de revisar y analizar la evidencia disponible sobre los factores que influyen en la adherencia de los pacientes con EPOC a los programas de rehabilitación pulmonar. Se realizó una búsqueda de literatura en las bases de datos Medline, Ovid, Science Direct, EMBASE, EBSCO, ISI-web of science y se definieron previamente criterios de selección que consideraran los factores que se relacionan con la asistencia y la adherencia en pacientes con EPOC en PRP. Como marco conceptual para el análisis de los resultados se utilizó el modelo de adherencia propuesto por la OMS. Como resultado significativo se encontró que los factores en la dimensión enfermedad (40%) y paciente (30%) son los que se mencionan con mayor frecuencia en los estudios, permitiendo identificar que el diseño de un programa de rehabilitación pulmonar debe tener en cuenta las necesidades específicas del paciente y su condición clínica. Se requiere un estudio que permita establecer las barreras y facilitadores de la adherencia en el medio colombiano (AU)

Currently, several studies have identified low adherence to pulmonary rehabilitation in patients with COPD, despite the positive effects of the treatment. Patient adherence to pulmonary rehabilitation is affected by factors such as the absence of family support, and the presence of multiple comorbidities, respiratory distress, anxiety and depression. Given that there is no conclusive evidence about which of these factors are most influential in determining adherence to pulmonary rehabilitation in patients with COPD, we conducted this scoping review to analyse the available evidence on the factors influencing the adherence of patients with COPD to pulmonary rehabilitation programs (PRP). A wide literature search was carried out in Medline, Ovid, Science Direct, EMBASE, EBSCO and ISI-web of science, with prior definition of the selection criteria that included the factors associated with healthcare and adherence in patients with COPD in PRP. We used the adherence model proposed by the WHO as a conceptual framework. As a significant result, we found that factors in the dimension of illness (40%) and patient (30%) were the most frequently found dimensions in the studies, revealing that the design of pulmonary rehabilitation programs must take into account the specific needs of the patient. Further studies are needed to establish barriers and facilitators of adherence among COPD patients to PRP in the Colombian setting (AU)

Ag nanoparticle effects on the thermoluminescent properties of monoclinic ZrO(2) exposed to ultraviolet and gamma radiation.

The goal of this work was to analyse ZrO(2) in the pure state and when doped with Ag nanoparticles, by electron microscopy, x-ray diffraction and thermoluminescence methods. According to the results obtained, Ag nanoparticles did not modify the morphology or the crystalline structure of the ZrO(2). The thermoluminescent (TL) response of pure ZrO(2) showed two peaks, one at 334 K and the other at 417 K, when it was exposed to ultraviolet (UV) radiation, and at 342 and 397 K when gamma radiation was used. For ZrO(2) impregnated with Ag nanoparticles a diminished TL intensity due to nanoparticle shielding was observed, but the glow curve shape was similar. However, when Ag nanoparticles were added during the ZrO(2) synthesis, a shift of the TL peaks towards higher temperature values with reference to pure ZrO(2) was observed. A linear dependence of the integrated TL signal as a function of the irradiation dose was observed in all analysed samples. It was possible to determine some kinetic parameters, such as activation energy, kinetic order and frequency factor, using the sequential quadratic programming glow curve deconvolution; it was found that these values are highly dependent on the type of radiation used. Ag nanoparticles present in ZrO(2) also modified the kinetic parameters, mainly when they were added during the synthesis of ZrO(2). Our results reinforce the possibilities of using pure and doped ZrO(2) as an appropriate dosimetric material in radiation physics.