Eleazar Samuel Kolosovas-Machuca

Distribution of skin temperature in Mexican children

Background: Infrared thermography can be a valuable diagnostic tool in the evaluation and management of several pathologies; however, the temperature pattern of the healthy body should be known in order to perform a more precise clinical evaluation.

Noninvasive determination of burn depth in children by digital infrared thermal imaging

Abstract. Digital infrared thermal imaging is used to assess noninvasively the severity of burn wounds in 13 pediatric patients. A delta-T (ΔT) parameter obtained by subtracting the temperature of a healthy contralateral region from the temperature of the burn wound is compared with the burn depth measured histopathologically. Thermal imaging results show that superficial dermal burns (IIa) show increased temperature compared with their contralateral healthy region, while deep dermal burns (IIb) show a lower temperature than their contralateral healthy region. This difference in temperature is statistically significant (p<0.0001) and provides a way of distinguishing deep dermal from superficial dermal burns. These results show that digital infrared thermal imaging could be used as a noninvasive procedure to assess burn wounds. An additional advantage of using thermal imaging, which can image a large skin surface area, is that it can be used to identify regions with different burn depths and estimate the size of the grafts needed for deep dermal burns.

Local use of insulin in wounds of diabetic patients: higher temperature, fibrosis, and angiogenesis.

Background: Clinical trials have shown the effectiveness of systemic and local insulin therapy in improving wound healing. Diabetic wounds remain a challenge for healthcare providers. Impaired angiogenesis and reduced granulation tissue formation contribute to inadequate wound healing. The aim of this study was to investigate the effect of local insulin administration in acute and chronic diabetic wounds. Methods: Eight diabetic patients presenting with full-thickness wounds, of different causes, were included in this study. Five wounds were due to necrobiosis, one to trauma, and two to postneoplasm resection. All wounds were treated with regular bedside treatment. In addition, half of the wound surface was treated with insulin and the other half did not receive insulin. Thermographic and biopsy specimens of the two sides were obtained on days 0 and 14. The presence of fibrosis, change in temperature, and amount of blood were evaluated. Results: Significant differences in the number of vessels were observed on the insulin-treated side (96 ± 47) when compared with the no-insulin side (32.88 ± 45) (p < 0.026). The percentage of fibrosis (insulin: 44.42 ± 30.42 percent versus no insulin: 12.38 ± 36.17 percent; p < 0.047) and the mean temperature (insulin: 1.27 ± 1.12°C versus no-insulin: 0.13 ± 1.22°C; p < 0.001) were also significantly different between sides. No adverse events related to the study occurred. Conclusion: The use of local insulin improves the formation of new blood vessels, increases fibrosis, and correlates with increased temperature. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, II.

Diagnosis of breast cancer by analysis of sialic acid concentrations in human saliva by surface-enhanced Raman spectroscopy of silver nanoparticles

Breast cancer is the most common type of malignant tumor among women and their second leading cause of cancer-related deaths. The most common method for screening and diagnosis is mammography. Nonetheless, two main problems have been identified. First, the dose of radiation received during the test prevents the method from the use on women who are < 40 years old. Second, there can be mammogram failure owing to the lack of tumor contrast with the fibrous tissue. Therefore, there is a need for screening methods that will help to identify high-risk cases. We developed a biological marker test that can help to identify them.Increased levels of sialic acid (SA) in saliva are known to correlated with breast cancer. In this study, we evaluated the feasibility of Raman spectroscopy as a method for quantification of SA in saliva, using citrate-reduced silver nanoparticles (cit-Ag-NPs) as a surface-enhanced Raman spectroscopy (SERS) substrate. Quantification of SA was accomplished by measuring its intensity in saliva and comparing it with a calibration curve of SA standards. The mean SA concentration in saliva was found to be significantly higher among 100 breast cancer patients (18.3 ± 9.4 mg·dL–1; mean ± SD) than among 106 healthy controls (3.5 ± 1.0 mg·dL–1). The SERS test showed sensitivity of 94% and specificity 98% for detection of patients with breast cancer, assuming that SA concentration >7 mg·dL–1 is a cutoff for positive test results. Our findings prove the usefulness of this SERS technique as a simple, convenient, and highly sensitive method of quantitative analysis of SA in saliva. The simplicity of this nanotechnological test may help to substantially reduce the mortality among patients with breast cancer by providing women with a simple, noninvasive screening test that can be applied regardless of age or density of breast tissue.

Design and Fabrication of Interdigital Nanocapacitors Coated with HfO2

In this article nickel interdigital capacitors were fabricated on top of silicon substrates. The capacitance of the interdigital capacitor was optimized by coating the electrodes with a 60 nm layer of HfO2. An analytical solution of the capacitance was compared to electromagnetic simulations using COMSOL and with experimental measurements. Results show that modeling interdigital capacitors using Finite Element Method software such as COMSOL is effective in the design and electrical characterization of these transducers.

Use of digital infrared imaging in the assessment of childhood psoriasis.

a chronic autoimmune diseasethat occurs when the immune system sendsout faulty signals that speed up the growthcycle of skin cells. It is well recognized that pso-riasis may have a markedly deleterious effecton the patient’s quality of life, with the physi-cal, social and psychological impact comparableto that seen in heart disease, diabetes mellitusand cancer (1). Psoriasis can affect children,approximately one-third of psoriasis patientsreport being diagnosed before being 20 yearsold (2). Self-esteem and behavior can be affectedby the disease and bullying has also been notedin clinical research (3).A wide variety of scoring systems have beenproposed to assess the severity of psoriasis;however, despite the importance of the evalua-tion of psoriasis there is a lack of consensus onthe most appropriate scoring system (4).The PASI (Psoriasis Area Severity Index)score is the most extensively studied clinicalseverity score for psoriasis and the most thor-oughly validated (4).In childhood and adolescence, the presence ofpsoriasis is associated with weight fluctuationsand an increased BMI, with poor cardiovascularprognosis (5). For this reason, it is difficult toassess the PASI, because the body surface area inchildhood and adolescence has larger variationsin short periods of time than the average adult.In this letter, thermal digital infrared imagingwas used to assess the progress and outcome ofan obese 9-year-old boy with psoriasis to objec-tively evaluate the affected area in a subjectwith significant surface area variations.The patient was a 9-year-old boy, obese(height 1.40 m, and weight 42.5 kg, both overthe 90th percentile), with a history of 4 yearswith a diagnosis of psoriasis and vitiligo treatedwith topical betamethasone as initial therapy,3 years after initial diagnosis a clinical worsen-ing of psoriatic lesions was observed and meth-otrexate was added to the treatment at a12.5 mg/week dose. No significant improve-ment was observed with treatment and thepatient maintained a PASI around 12.6 ± 2 for6 months. After a routine lab work was per-formed on the patient an infectious pyelonephri-tis was found, for that reason the methotrexatewas suspended and 50 mg of acitretin per daywas initiated and the psoriatic lesions weremonitored using digital infrared thermal imag-ing to evaluate the intensity of the lesions as thePASI alone gave significant variations due to thebody mass fluctuations observed on the patientduring the duration of treatment.Infrared imaging was performed using aFLIR T400 infrared camera (FLIR Systems, Wil-sonville, OR, USA) which has a 320 9 240 FocalPlane Array of uncooled microbolometers witha spectral range of 7.5–13 lm and a thermalsensitivity of 50 mK at 30°C.The thermographic analysis was performedusing FLIR QuickReport v1.2 (FLIR Systems,Wilsonville, OR, USA) which includes a tool toobtain maximum, minimum, and average tem-perature of a user-defined area.Before treatment the patient presented scat-tered lesions mostly around the right part ofthe chest and on the abdominal area (Fig. 1a),

Pain Measurement through Temperature Changes in Children Undergoing Dental Extractions

Background and Objective. Pain evaluation in children can be a difficult task, since it possesses sensory and affective components that are often hard to discriminate. Infrared thermography has previously been used as a diagnostic tool for pain detection in animals; therefore, the aim of this study was to assess the presence of temperature changes during dental extractions and to evaluate its correlation with heart rate changes as markers of pain and discomfort. Methods. Thermographic changes in the lacrimal caruncle and heart rate measurements were recorded in healthy children scheduled for dental extraction before and during the procedure and compared. Afterwards, correlation between temperature and heart rate was assessed. Results. We found significant differences in temperature and heart rate before the procedure and during the dental extraction (mean difference 4.07°C, p < 0.001, and 18.11 beats per minute, p < 0.001) and no evidence of correlation between both measurements. Conclusion. Thermographic changes in the lacrimal caruncle can be detected in patients who undergo dental extractions. These changes appear to be stable throughout time and to possess very little intersubject variation, thus making them a candidate for a surrogate marker of pain and discomfort. Future studies should be performed to confirm this claim.

Resistance-based biosensor of Multi-Walled Carbon Nanotubes.

Multi-Walled Carbon Nanotubes (MWNTs) are a good choice for resistive biosensors due to their great resistance changes when immunoreactions take place, they are also low-cost, more biocompatible than single-walled carbon nanotubes, and resistive measurement equipment is usually not expensive and readily available. In this work a novel resistive biosensor based on the immobilization of an antigen through a silanization process over the surface of Multi-Walled Carbon Nanotubes (MWNTs) is reported. Results show that the biosensor increases its conductivity when adding the antigen and decreases when adding the antibody making them good candidates for disease diagnosis.

Bioanalysis by Immobilization of Antibodies on Hafnium(IV) Oxide with 3-Aminopropyltriethoxysilane

ABSTRACT Self-assembled monolayers of 3-aminopropyltriethoxysilane (APTES) are commonly used to promote adhesion between substrates and organic or metallic materials with applications ranging from advanced composites to biomolecular lab-on-a-chip devices. In this work, the silanization on hafnium oxide (HfO2) films is reported. The layers of HfO2 were deposited on Si (001) substrates by atomic layer deposition. The grown HfO2 films were modified in accordance with three main steps: oxidation, silanization, and cross-linking of the APTES monolayer using glutaraldehyde as cross-linking agent. Microscopic features were characterized by atomic force microscopy. Further, both bovine serum albumin and antibovine serum albumin agents were deposited on the samples to test their potential use as the immunosensor.

Evaluation of noise environments during daily activities of university students

Noise conditions specifically in areas inside university facilities and its impact on the quality of life of university students are topics that have received little attention. This paper presents a study of the noise conditions in which university students of various institutions in Madrid, Spain, carry out their daily studies. A representative number of measurements was carried out using noise dosemeters and dataloggers in order to evaluate the levels of noise, noise dose and exposure to noise during school periods and extracurricular activities. The results were compared with the recommendations given by current environmental noise regulations. This paper was complemented with a survey to get to know how students perceive the exposure to noise in university environments.