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1.
Appl Opt ; 62(24): 6534-6541, 2023 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-37706848

RESUMEN

In this work, we study multimodal interference filters with a graphite oxide coating. Use of the multimodal interference filter shows a distinctive peak in the signal spectrum, and when using the exfoliated graphite coated multimodal interference filter, the signal shows different spectral changes, such as the full width at half maximum of the curve, the maximum power, and central wavelength, which indicates that graphite oxide absorbs part of the energy. In addition, microscope observations when a He-Ne laser is passed through the filter confirm that graphite oxide is adhered to the filter.

2.
Opt Lett ; 44(3): 679-682, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30702709

RESUMEN

We present a novel approach for imaging through scattering media that combines the principles of Fourier spatial filtering and single-pixel imaging. We compare the performance of our single-pixel imaging setup with that of a conventional system. First, we show that a single-pixel camera does not reduce the frequency content of the object, when a small pinhole is used as a low-pass filter at the detection side. Second, we show that the introduction of Fourier gating improves the contrast of imaging through scattering media in both optical systems. We conclude that single-pixel imaging fits better than conventional imaging on imaging through scattering media by the Fourier gating.

3.
Appl Opt ; 57(7): B67-B73, 2018 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-29521996

RESUMEN

Single-pixel cameras have been successfully used in different imaging applications in the last years. One of the key elements affecting the quality of these cameras is the photodetector. Here, we develop a numerical model of a single-pixel camera, which takes into account not only the characteristics of the incident light but also the physical properties of the detector. In particular, our model considers the photocurrent, the dark current, the photocurrent shot noise, the dark-current shot noise, and the Johnson-Nyquist (thermal) noise of the photodiode used as a light detector. The model establishes a clear relationship between the electric signal and the quality of the final image. This allows us to perform a systematic study of the quality of the image obtained with single-pixel cameras in different contexts. In particular, we study the signal-to-noise ratio as a function of the optical power of the incident light, the wavelength, and the photodiode temperature. The results of the model are compared with those obtained experimentally with a single-pixel camera.

4.
Neurologia ; 32(1): 15-21, 2017.
Artículo en Inglés, Español | MEDLINE | ID: mdl-25704984

RESUMEN

OBJECTIVE: This study evaluates care-related sociodemographic, clinical, and imaging factors and influences associated with outcome at discharge in patients with aneurismal subarachnoid haemorrhage. PATIENTS AND METHOD: Retrospective cohort study in 334 patients treated at Hospital Hermanos Ameijeiras in Havana, Cuba between October 2005 and June 2014. RESULTS: Logistic regression analysis determined that the following factors were associated with higher risk of poor outcome: age older than 65 years (OR 3.51, 95% CI 1.79-5.7, P=.031), female sex (OR 2.17, 95% CI 1.22-3.84, P=.0067), systolic hypertension (OR 4.82, 95% CI 2.27-9.8, P=.0001), and hyperglycaemia at admission (OR 3.93, 95% CI 2.10-7.53, P=.0003). Certain complications were also associated with poor prognosis, including respiratory infection (OR 2.73, 95% CI 1.27-5.85, P=.0085), electrolyte disturbances (OR 3.33, 95% CI 1.33-8.28, P=.0073), hydrocephalus (OR 2.21, 95% CI 1.05-4.63, P=.0039), rebleeding (OR 16.50, 95% CI 8.24-41.24, P=.0000), symptomatic vasospasm (OR 19.00, 95% CI 8.86-41.24, P=.0000), cerebral ischaemia (OR 3.82, 95% CI 1.87-7.80, P=.000) and multiplex rebleeding (OR 6.69, 95% CI 1.35-36.39, P=.0019). Grades of iii and iv on the World Federation of Neurological Surgeons (OR 2.09, 95% CI 1.12-3.91, P=.0021) and Fisher scales (OR 5.18, 95% CI 2.65-10.29, P=.0008) were also related to poor outcome. CONCLUSIONS: Outcome of aneurysmal subarachnoid haemorrhage was related to age, sex, clinical status at admission to the stroke unit, imaging findings according to the Fisher scale, blood pressure, glycaemia and such complications as electrolyte disturbances, hydrocephalus, rebleeding, and multiplex rebleeding.


Asunto(s)
Índice de Severidad de la Enfermedad , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/terapia , Factores de Edad , Cuba , Femenino , Humanos , Hiperglucemia , Hipertensión/etiología , Masculino , Persona de Mediana Edad , Alta del Paciente , Pronóstico , Estudios Retrospectivos , Factores Sexuales , Hemorragia Subaracnoidea/diagnóstico por imagen
5.
Rev Cient (Maracaibo) ; 26(2): 86-94, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28713196

RESUMEN

The Tamaulipan rock rattlesnake (Crotalus lepidus morulus) is a montane snake that occurs in the humid pine-oak forest and the upper cloud forest of the Sierra Madre Oriental in southwestern Tamaulipas, central Nuevo Leon, and southeastern Coahuila in Mexico. Venom from this rattlesnake was fractionated by High-Performance Liquid Chromatography for the purpose of discovering disintegrin molecules. Disintegrins are non-enzymatic, small molecular weight peptides that interfere with cell-cell and cell-matrix interactions by binding to various cell receptors. Eleven fractions were collected by anion exchange chromatography and pooled into six groups (I, II, III, IV, V, and VI). Proteins of the six groups were analyzed by SDS-PAGE and western blot using antibodies raised against a disintegrin. The antibodies recognized different protein bands in five (II, III, IV, V, and VI) of six groups in a molecular mass range of 7 to 105 kDa. Western blot analysis revealed fewer protein bands in the higher molecular mass range and two bands in the disintegrin weight range in group II compared with the other four groups. Proteins in group II were further separated into nine fractions using reverse phase C18 chromatography. Fraction 4 inhibited platelet aggregation and was named morulustatin, which exhibited a single band with a molecular mass of approximately 7 kDa. Mass spectrometry analysis of fraction 4 revealed the identification of disintegrin peptides LRPGAQCADGLCCDQCR (MH+ 2035.84) and AGEECDCGSPANCCDAATCK (MH+ 2328.82). Morulustatin inhibited ADP-induced platelet aggregation in human whole blood and was concentration-dependent with an IC50 of 89.5 nM ± 12.

6.
Appl Opt ; 54(14): 4439-46, 2015 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-25967499

RESUMEN

For an expert nose, the aroma of a beverage is a fingerprint that can be used to certify its authenticity, distinguish between distillation processes, or even identify the raw material used to fabricate it. In this work, we propose a simple, automatic, and repeatable optical method, which can be used as a first and quick test to authenticate tequila samples. This method is based on the measurement of beam intensity changes, using the surface plasmon resonance technique, operating at a fixed angle. We observed that each tequila, depending on the alcohol content and aging process, produces a specific change in measured intensity level.

7.
Eur J Gynaecol Oncol ; 36(1): 21-4, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25872329

RESUMEN

PURPOSE OF INVESTIGATION: To determine the prevalence of endometriosis in patients with epithelial ovarian cancer and explore the differences between women with endometrioid and clear-cell histologic subtypes with and without associated endometriosis. MATERIALS AND METHODS: The medical charts of 496 patients with epithelial ovarian cancer at the Hospital Virgin de la Arrixaca (Murcia, Spain) between 1971 and 2010 were reviewed. RESULTS: Endometriosis was present in 27 (5.4%) of the 496 cases (p < 0001), and was associated with the endometrioid histotype in 13/45 cases (29%) and with the clear cell histotype in 7/22 (32%). The prevalence of an association with endometriosis according to histologic type was 28.8% (13/45) for endometrioid carcinoma and 31.8% (7/22) for clear-cell carcinoma. CONCLUSION: Both endometrioid and clear-cell ovarians tumours are associated with pelvic endometriosis. Patients with endometiosis associated ovarian cancer differ from non-endometiosis associated ovarian cancer in their clinical characteristics.


Asunto(s)
Adenocarcinoma de Células Claras/epidemiología , Carcinoma Endometrioide/epidemiología , Endometriosis/epidemiología , Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/patología , Adenocarcinoma de Células Claras/patología , Adulto , Anciano , Carcinoma Endometrioide/patología , Femenino , Humanos , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , España/epidemiología
8.
J Opt Soc Am A Opt Image Sci Vis ; 31(10): 2244-8, 2014 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-25401251

RESUMEN

Determining the invisibility of an optical cloak intended to hide something has become a complex problem in recent years. There are many invisibility mechanisms, the performance is quite different from technique to technique, and it is desirable to have a precise metric for their comparison. Here, we propose a simple metric that assesses the perceived invisibility. This invisibility index is based on the fact that the human visual system (HVS) is highly sensitive to spatial frequencies, and then uses the Fourier transform and the contrast sensitivity function of the HVS to assess invisibility.

9.
Rev Esp Cir Ortop Traumatol ; 68(3): T253-T261, 2024.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38232932

RESUMEN

INTRODUCTION: The main complication of percutaneous iliosacral screw fixation is implant malposition, which can lead to vascular and nerve damage. The anatomical variability of the sacrum can make screw insertion difficult under fluoroscopic guidance. Among the methods described to improve the accuracy of this technique, stands out the use of computed tomography (CT). The aim of this study is to compare the results of iliosacral screw insertion with fluoroscopy or CT navigation. METHODOLOGY: Retrospective cohort study of 66 iliosacral screws in 56 patients during 11 years. The screws were inserted with fluoroscopy in the operating room or with CT in the radiodiagnosis area. We collected data on patient characteristics, lesions, treatment, and clinical and radiological results. RESULTS: Forty-seven screws were inserted with fluoroscopy and 19 with CT. A percentage of 18.2 of screws perforated the S1 osseous corridor. All of them were inserted with fluoroscopy guidance (0 vs. 34%; p<0.01). Those operated with CT accumulated more sacral dysmorphism criteria than those operated with fluoroscopy (2.2 vs. 1.6; p=0.02). The S1 corridor on the axial CT view was narrower in those in whom perforation had occurred (18.8 vs. 21.0mm; p=0.02). Two cases with perforation developed S1 radiculalgia. Two endopelvic screws had to be removed. CONCLUSION: We advise the use of CT guidance for iliosacral screw insertion in patients with sacral dysmorphism or narrow S1 corridors in facilities where other navigation methods are not available.

10.
Rev Esp Cir Ortop Traumatol ; 68(4): T363-T372, 2024.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38325573

RESUMEN

INTRODUCTION: Rotational ankle fractures are common, have diverse personalities and affect both robust and fragile patients. Postoperative complications are frequent, creating a sizeable economic burden. The primary purpose of this study was to expand current knowledge on predictors of postoperative complications after low-energy ankle fracture fixation. MATERIALS AND METHODS: A retrospective single-center cohort study was completed of patients undergoing internal fixation OF low-energy ankle fractures. The primary outcome was first-year postoperative complications, classified as major (surgical) or minor (non-surgical). Data on patients, their injuries, and treatments were collected. To identify potential predictors of outcomes, logistic regression methods were used, with a backward-stepwise method used for model fitting. RESULTS: In total, 663 patients of median age 59 years were analysed. We found a high rate of complications (28.4%), with wound-healing issues and infections predominant. Overall, 14.8% had minor complications, while 13.6% required an unplanned reoperation. On multivariable analysis, the most consistent predictors of complications were older age (OR: 1.02 per year), longer operating time (3.32 per hour), and smoking (2.91). CONCLUSIONS: Older patients and smokers who sustain fractures requiring more complex surgery are at higher risk of postoperative complications.

11.
Facts Views Vis Obgyn ; 15(4): 351-353, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38128093

RESUMEN

Xanthogranulomatous endometritis (XGE) is an uncommon inflammatory benign condition that can mimic endometrial cancer. The majority of the reported cases of XGE have been observed in postmenopausal women, often presenting clinically as haematometra or benign senile pyometra. We report a case of XGE in a 73-year-old woman who presented with pyometra. Diagnostic hysteroscopy is an important tool when accompanied by endometrial samples for histology in suspected cases. Knowledge of this uncommon disease is crucial for accurate diagnosis. XGE is a benign condition, however, there have been reported cases of chronic active XGE and bacterial infection in which hysterectomy was required due to complications.

12.
Plast Reconstr Surg ; 151(4): 749-757, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36729920

RESUMEN

BACKGROUND: The authors present a retrospective, comparative, and analytical cohort study, that aimed to prove the utility of unilateral or asymmetrical bony wedge resection to straighten the twisted nose as applied in let-down and push-down methods. The study involved objective angle measurements preoperatively and postoperatively on frontal view photographs. METHODS: Preoperative and postoperative angle measurements were made on frontal view photographs of 78 patients with twisted noses classified as type C and type I. Angles of deviation were obtained using Scion Image software, measured in degrees. Statistical analysis was performed using Excel v15.13.3. RESULTS: Forty-two patients had twisted nose type C and 28 patients had twisted nose type I. The mean age was 19 years. There was an 81% improvement ratio for twisted nose type C and 79% for twisted nose type I, and the angle correction for each type of nasal deformity was statistically significant ( P < 0.01). The majority of postoperative results were classified as excellent to good, with the exception of four cases with bad outcomes, including two patients with type C and two with type I deviations. CONCLUSIONS: Unilateral or asymmetrical bony wedge resection is a modification of the let-down rhinoplasty technique. This study demonstrates statistically significant improvements in straightening twisted noses among patients with or without preoperative hump and preserving the nasal dorsum. The authors found this modification better suited for type C deviations. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.


Asunto(s)
Rinoplastia , Humanos , Adulto Joven , Adulto , Rinoplastia/métodos , Estudios de Cohortes , Estudios Retrospectivos , Tabique Nasal/cirugía , Resultado del Tratamiento , Nariz/cirugía
13.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38043738

RESUMEN

INTRODUCTION: Rotational ankle fractures are common, have diverse personalities and affect both robust and fragile patients. Postoperative complications are frequent, creating a sizeable economic burden. The primary purpose of this study was to expand current knowledge on predictors of postoperative complications after low-energy ankle fracture fixation. MATERIALS AND METHODS: A retrospective single-center cohort study was completed of patients undergoing internal fixation OF low-energy ankle fractures. The primary outcome was first-year postoperative complications, classified as major (surgical) or minor (non-surgical). Data on patients, their injuries, and treatments were collected. To identify potential predictors of outcomes, logistic regression methods were used, with a backward-stepwise method used for model fitting. RESULTS: In total, 663 patients of median age 59 years were analyzed. We found a high rate of complications (28.4%), with wound-healing issues and infections predominant. Overall, 14.8% had minor complications, while 13.6% required an unplanned reoperation. On multivariable analysis, the most consistent predictors of complications were older age (OR=1.02 per year), longer operating time (3.32 per hour), and smoking (2.91). CONCLUSIONS: Older patients and smokers who sustain fractures requiring more complex surgery are at higher risk of postoperative complications.

14.
Artículo en Inglés, Español | MEDLINE | ID: mdl-37918689

RESUMEN

INTRODUCTION: The main complication of percutaneous iliosacral screw fixation is implant malposition, which can lead to vascular and nerve damage. The anatomical variability of the sacrum can make screw insertion difficult under fluoroscopic guidance. Among the methods described to improve the accuracy of this technique, stands out the use of computed tomography (CT). The aim of this study is to compare the results of iliosacral screw insertion with fluoroscopy or CT navigation. METHODOLOGY: Retrospective cohort study of 66 iliosacral screws in 56 patients during 11 years. The screws were inserted with fluoroscopy in the operating room or with CT in the radiodiagnosis area. We collected data on patient characteristics, lesions, treatment, and clinical and radiological results. RESULTS: Forty-seven screws were inserted with fluoroscopy and 19 with CT. A percentage of 18.2 of screws perforated the S1 osseous corridor. All of them were inserted with fluoroscopy guidance (0 vs. 34%; p<0.01). Those operated with CT accumulated more sacral dysmorphism criteria than those operated with fluoroscopy (2.2 vs. 1.6; p=0.02). The S1 corridor on the axial CT view was narrower in those in whom perforation had occurred (18.8 vs. 21.0mm; p=0.02). Two cases with perforation developed S1 radiculalgia. Two endopelvic screws had to be removed. CONCLUSION: We advise the use of CT guidance for iliosacral screw insertion in patients with sacral dysmorphism or narrow S1 corridors in facilities where other navigation methods are not available.

15.
J Vector Borne Dis ; 49(1): 8-14, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22585236

RESUMEN

BACKGROUND & OBJECTIVES: The saliva of the Phlebotominae is highly immunogenic to the vertebrate host and is a determining factor in the Leishmania infection. The aim of this work was to study the saliva of Lutzomyia ovallesi as a possible risk marker for the transmission of Leishmania. METHODS: Two populations of L. ovallesi from different geographical areas and subjected to different environmental conditions were compared by geometric morphometry of the wings, by protein profile analysis of salivary glands and by assessing the presence of anti-saliva protein in human sera confronted with laboratory L. ovallesi saliva. RESULTS: The results showed differences in the isometric size and structure of the wings but no allometric effects. Protein profiles of salivary glands of both the L. ovallesi populations studied were found to be similar, based on 11 protein bands with molecular weights ranging from 16 to 99 kDa. Anti-saliva antibodies were present in human sera, but human sera infected and uninfected with leishmaniasis could not be differentiated. INTERPRETATION & CONCLUSION: We conclude that the saliva of laboratory-reared L. ovallesi is representative of that of the wild population. It is suggested to study the presence of anti-saliva antibodies in other species of sandflies and mosquitoes.


Asunto(s)
Anticuerpos/sangre , Biomarcadores/sangre , Proteínas de Insectos/análisis , Proteínas de Insectos/inmunología , Psychodidae/química , Adolescente , Adulto , Animales , Femenino , Humanos , Masculino , Saliva/química , Proteínas y Péptidos Salivales/análisis , Venezuela
16.
Trans R Soc Trop Med Hyg ; 116(7): 673-675, 2022 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34850236

RESUMEN

BACKGROUND: Cyclosporiasis has a marked seasonality. Few community-based studies have addressed this issue and there are no reports from Venezuela. A study was conducted to determine the seasonal variation of infection in a community from Falcon State, Venezuela. METHODS: A sample of 732 individuals was collected for 1 y. Stools were examined with modified Ziehl-Neelsen carbolfuchsin staining of ethyl acetate-formalin concentrates and ultraviolet epiflorescence of wet mounts. RESULTS: Cyclospora prevalence was 9.9% (73/732) with monthly variation from 0% to 35.3%. A trend of increased infections coinciding with the rainy time was observed (p<0.001). CONCLUSIONS: Cyclosporiasis is common in this area with high endemicity during the rainy periods.


Asunto(s)
Cyclospora , Ciclosporiasis , Ciclosporiasis/epidemiología , Diarrea/epidemiología , Heces , Humanos , Estaciones del Año , Venezuela/epidemiología
17.
Nat Commun ; 13(1): 5779, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-36182942

RESUMEN

Scattering can rapidly degrade our ability to form an optical image, to the point where only speckle-like patterns can be measured. Truly non-invasive imaging through a strongly scattering obstacle is difficult, and usually reliant on a computationally intensive numerical reconstruction. In this work we show that, by combining the cross-correlations of the measured speckle pattern at different times, it is possible to track a moving object with minimal computational effort and over a large field of view.

18.
Medicine (Madr) ; 13(55): 3246-3249, 2022 May.
Artículo en Español | MEDLINE | ID: mdl-35582698

RESUMEN

SARS-CoV-2 infection causes a wide spectrum of symptoms with varying degrees of severity, from asymptomatic cases or cases in the form of self-limiting influenza-like illness to cases of rapidly progressing respiratory distress syndrome due to an anomalous immune system response in the form of a cytokine storm. Thrombotic complications are also common. Multiple antiviral treatments have been tested in COVID-19 without favorable outcomes. Only remdesivir may be useful, but not in all cases, and its use is controversial. On the contrary, immunomodulating treatments have the most solid evidence, particularly glucocorticoids. Other more specific immunosuppressors, such as interleukin-6 inhibitors, have also shown favorable results and many others are currently being studied. Thromboprophylaxis is the other pillar of COVID-19 treatment, although the anticoagulant dose to be used is still being discussed.

19.
J Nutr Health Aging ; 26(10): 926-935, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36259581

RESUMEN

BACKGROUND: The gut microbiota can impact older adults' health, especially in patients with frailty syndrome. Understanding the association between the gut microbiota and frailty syndrome will help to explain the etiology of age-related diseases. Low-grade systemic inflammation is a factor leading to geriatric disorders, which is known as "inflammaging". Intestinal dysbiosis has a direct relationship with low-grade systemic inflammation because when the natural gut barrier is altered by age or other factors, some microorganisms or their metabolites can cross this barrier and reach the systemic circulation. OBJECTIVES: This review had two general goals: first, to describe the characteristics of the gut microbiota associated with age-related diseases, specifically frailty syndrome. The second aim was to identify potential interventions to improve the composition and function of intestinal microbiota, consequently lessening the burden of patients with frailty syndrome. METHODS: A search of scientific evidence was performed in PubMed, Science Direct, and Redalyc using keywords such as "frailty", "elderly", "nutrient interventions", "probiotics", and "prebiotics". We included studies reporting the effects of nutrient supplementation on frailty syndrome and older adults. These studies were analyzed to identify novel therapeutic alternatives to improve gut microbiota characteristics as well as subclinical signs related to this condition. RESULTS: The gut microbiota participates in many metabolic processes that have an impact on the brain, muscles, and other organs. These processes integrate feedback mechanisms, comprising their respective axis with the intestine and the gut microbiota. Alterations in these associations can lead to frailty. We report a few interventions that demonstrate that prebiotics and probiotics could modulate the gut microbiota in humans. Furthermore, other nutritional interventions could be used in patients with frailty syndrome. CONCLUSION: Probiotics and prebiotics may potentially prevent frailty syndrome or improve the quality of life of patients with this disorder. However, there is not enough information about their appropriate doses and periods of administration. Therefore, further investigations are required to determine these factors and improve their efficacy as therapeutic approaches for frailty syndrome.


Asunto(s)
Fragilidad , Microbioma Gastrointestinal , Probióticos , Humanos , Anciano , Prebióticos , Calidad de Vida , Anciano Frágil , Probióticos/uso terapéutico , Inflamación
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