ABSTRACT
BACKGROUND: Diabetes mellitus (DM) is a chronic metabolic disorder characterised by high blood sugar (BS) levels due to impaired insulin production or insulin resistance. It is a global health concern with significant implications for morbidity and mortality. Persian medicine has long utilised natural remedies, such as Pistacia atlantica Desf., for various diseases. In this randomised clinical trial, the effects of P. atlantica oleoresin in the improvement of lipid profiles, glucose indices and blood pressure (BP) were assessed in patients with Type 2 DM. MATERIALS AND METHODS: In this randomised, single-blind, placebo-controlled study, 42 patients with Type 2 DM were randomly allocated to receive either P. atlantica oleoresin or placebo capsule for 3 months. Patients were evaluated prior to and 12 weeks after the beginning of the intervention, in terms of changes in lipid profiles, glucose indices and BP. RESULTS: After 3 months, the mean BP in patients with DM receiving P. atlantica oleoresin was significantly reduced compared with the baseline (p = 0.001). Also, these changes were significantly higher than those of the control group. The mean of total cholesterol (p = 0.89), low-density lipoprotein (LDL) (p = 0.43) and triglyceride (TG) (p = 0.98) in the intervention group after 3 months was lower than that in the control group, but this difference was not statistically significant. CONCLUSION: After 3 months, there was no significant difference between the P. atlantica and control groups in terms of blood sugar and lipid profiles. The mean BP in patients with DM receiving P. atlantica oleoresin was significantly reduced compared with that in the beginning of the study. Also, these changes were significant compared with the control group.
Subject(s)
Blood Glucose , Blood Pressure , Diabetes Mellitus, Type 2 , Pistacia , Plant Extracts , Humans , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/complications , Male , Single-Blind Method , Middle Aged , Female , Plant Extracts/pharmacology , Plant Extracts/administration & dosage , Plant Extracts/therapeutic use , Blood Glucose/metabolism , Adult , Lipids/blood , Phytotherapy , AgedABSTRACT
BACKGROUND: Mucinous cystadenocarcinoma is a relatively uncommon histological subtype of breast cancer that is a cystic form of papillary mucinous carcinoma. It is regularly negative for estrogen and progesterone receptors and it is most often diagnosed in older than 55-60 years old. The incidence of breast mucinous cystadenocarcinoma is about 1-6% of primary breast cancers. Here, we present a case of breast mucinous cystadenocarcinoma of left breast in a 69-year-old female which is positive for estrogen and progesterone receptors. CASE PRESENTATION: In this article, we describe a case of a-69-year-old female with a painful mass in her left breast. Based on intraoperative pathology consult, neoplastic tissue mostly floating in mucinous lakes with invasion to surrounding stroma was seen. Immunohistochemistry profile showed positive estrogen and progesterone receptors and negative for HER2. CONCLUSION: Mucinous cystadenocarcinoma of breast is typically triple negative for hormone receptors. But ER and PR positive variant of this tumor is rare, giving the chance of a better prognosis for the patient with hormonal therapy.
ABSTRACT
OBJECTIVE: Several studies have shown the antispasmodic activity of Matricariarecutita without detailing the underlying mechanism(s). The present study was designed to determine whether the antispasmodic mechanisms of M. recutita extract mediated via histaminergic/cholinergic receptors, Ca2+channels, activation of PKA2 and NO release in isolated rabbit jejunum. MATERIALS AND METHODS: The concentration- dependent (3 × 10-3-1.3 × 10-2 mg/ml) antispasmodic effect of the hydro-alcoholic extract of M. recutita flowers was studied in isolated rabbit jejunum. The isolated jejunum preparations were divided into seven groups, including the pharmacological probes that modulate cholinergic, histaminergic, and nitrergic receptors, as well as PKA2. RESULTS: M. recutita inhibited spontaneous smooth muscle contractility of the jejunum in a concentration-dependent manner (3 × 10-3-1.3 × 10-2 mg/ml) and reduced both K+- and Ca2+-induced contractions, which is similar to the effect of verapamil. The antispasmodic effect of M. recutita was inhibited by H89 (a PKA2 inhibitor). The myorelaxant effect of M. recutita increased in the presence of ACh/His and H89. CONCLUSION: M. recutita evoked antispasmodic and spasmolytic effects mediated through different signaling pathways. Our results have shown this dual inhibitory effect is mediated by blocking Ca2+ channels, activating His and ACh receptors, releasing NO, and activating PKA2.
ABSTRACT
We herein report a case of colonic polyposis, colorectal carcinoma and large B-cell lymphoma in a 22-year-old male patient with a previous history of childhood lymphoblastic lymphoma. Eight years after lymphoblastic lymphoma, which presented as mediastinal mass and superior vena cava syndrome, the patient complained of abdominal pain, lower gastrointestinal bleeding and an abdominal mass. The surgical exploration revealed numerous mucosal polyps throughout the large intestine, and multifocal masses in the ascending and transverse colon and the rectosigmoid region. A retroperitoneal mass was also found. The pathological examination revealed >100 tubular adenomatous polyps and a multifocal, well-differentiated adenocarcinoma, with lymph node involvement and pericolic invasion. Interestingly, the immunohistochemical studies confirmed the malignant undifferentiated retroperitoneal mass as large B-cell lymphoma. Over a period of ~10 years, the patient had suffered from three different malignancies. To the best of our knowledge, such a combination of sporadic adenomatous colonic polyposis, colorectal carcinoma and two extra-intestinal non-Hodgkin lymphomas has not been reported to date. It should be considered that each malignancy increases the risk for other neoplastic diseases and a close follow-up is crucial for early detection of second malignancies and neoplastic syndromes.
ABSTRACT
UNLABELLED: The ways that fibroblasts remodel their environment are central to wound healing, development of musculoskeletal tissues, and progression of pathologies such as fibrosis. However, the changes that fibroblasts make to the material around them and the mechanical consequences of these changes have proven difficult to quantify, especially in realistic, viscoelastic three-dimensional culture environments, leaving a critical need for quantitative data. Here, we observed the mechanisms and quantified the mechanical effects of fibroblast remodeling in engineered tissue constructs (ETCs) comprised of reconstituted rat tail (type I) collagen and human fibroblast cells. To study the effects of remodeling on tissue mechanics, stress-relaxation tests were performed on ETCs cultured for 24, 48, and 72h. ETCs were treated with deoxycholate and tested again to assess the ECM response. Viscoelastic relaxation spectra were obtained using the generalized Maxwell model. Cells exhibited viscoelastic damping at two finite time constants over which the ECM showed little damping, approximately 0.2s and 10-30s. Different finite time constants in the range of 1-7000s were attributed to ECM relaxation. Cells remodeled the ECM to produce a relaxation time constant on the order of 7000s, and to merge relaxation finite time constants in the 0.5-2s range into a single time content in the 1s range. Results shed light on hierarchical deformation mechanisms in tissues, and on pathologies related to collagen relaxation such as diastolic dysfunction. STATEMENT OF SIGNIFICANCE: As fibroblasts proliferate within and remodel a tissue, they change the tissue mechanically. Quantifying these changes is critical for understanding wound healing and the development of pathologies such as cardiac fibrosis. Here, we characterize for the first time the spectrum of viscoelastic (rate-dependent) changes arising from the remodeling of reconstituted collagen by fibroblasts. The method also provides estimates of the viscoelastic spectra of fibroblasts within a three-dimensional culture environment. Results are of particular interest because of the ways that fibroblasts alter the mechanical response of collagen at loading frequencies associated with cardiac contraction in humans.
Subject(s)
Collagen Type I/chemistry , Fibroblasts/metabolism , Tissue Scaffolds/chemistry , Animals , Cells, Cultured , Fibroblasts/cytology , Humans , RatsABSTRACT
Viscoelastic relaxation spectra are essential for predicting and interpreting the mechanical responses of materials and structures. For biological tissues, these spectra must usually be estimated from viscoelastic relaxation tests. Interpreting viscoelastic relaxation tests is challenging because the inverse problem is expensive computationally. We present here an efficient algorithm that enables rapid identification of viscoelastic relaxation spectra. The algorithm was tested against trial data to characterize its robustness and identify its limitations and strengths. The algorithm was then applied to identify the viscoelastic response of reconstituted collagen, revealing an extensive distribution of viscoelastic time constants.
Subject(s)
Elasticity , Materials Testing , Algorithms , Collagen/metabolism , Models, Theoretical , Spectrum Analysis , ViscosityABSTRACT
Ankylosing spondylitis (AS) is a chronic inflammatory disease that affects 1% of the general population. As one of the most severe types of spondyloarthropathy, AS affects the spinal vertebrae and sacroiliac joints, causing debilitating pain and loss of mobility. The goal of this review is to provide an overview of AS, from the pathophysiological changes that occur as the disease progresses, to genetic factors that are involved with its onset. Considering the high prevalence in the population, and the debilitating life changes that occur as a result of the disease, a strong emphasis is placed on the diagnostic imaging methods that are used to detect this condition, as well as several treatment methods that could improve the health of individuals diagnosed with AS.
ABSTRACT
Carpal tunnel syndrome (CTS) is the most commonly diagnosed disabling condition of the upper extremities. It is the most commonly known and prevalent type of peripheral entrapment neuropathy that accounts for about 90% of all entrapment neuropathies. This review aims to provide an outline of CTS by considering anatomy, pathophysiology, clinical manifestation, diagnostic modalities and management of this common condition, with an emphasis on the diagnostic imaging evaluation.
ABSTRACT
Reducing the infarct size in acute myocardial infarction is one of the most important goals driving new drug research and development. During the last two decades, many clinical studies have found cardioprotective effects of corticosteroids, but their exact role in ischemic preconditioning remains questionable. The aim of the present study was to determine the protective effects of hydrocortisone sodium succinate on myocardial preconditioning in rabbit hearts. Twenty-four male New Zealand rabbits were divided randomly & equally in four groups: 1) control, 2) Infarct, 3) Ischemic preconditioning (IP) and 4) Hydrocortisone (HYD). The HYD group received 50mg/kg Hydrocortisone 45min before major ischemia. Serum levels of cardiac troponin-T(cTNT) and cortisole were measured before and after the protocols. Triphenyl-tetrazolium chloride staining was used to determine the infarcted area. In the present study, exogenous hydrocortisone decreased infarct size by 53 percent in comparison to the infarct group. Serum level of cortisole was increased in the IP and HYD groups, and was significant in the HYD group (p<0.01). An increasing trend in cortisole level was associated with a decreasing trend in infarct size and cTNT in the IP and HYD groups (p>0.01). In conclusion, we showed that hydrocortisone has cardioprotective effects when injected before the onset of myocardial infarction. In addition, we have proposed for the first time that endogenous hydrocortisone may play a role in ischemic preconditioning phenomena.
La reducción del tamaño del infarto en el infarto agudo de miocardio es una de las metas más importantes que impulsan la investigación y el desarrollo de nuevos fármacos. Durante las dos últimas décadas, muchos estudios clínicos han encontrado efectos cardioprotectores de los corticosteroides, pero su papel exacto en el preacondicionamiento isquémico sigue siendo cuestionable. El objetivo del presente estudio fue determinar los efectos protectores de succinato sódico de hidrocortisona en el preacondicionamiento del miocardio en el corazón de conejo. Veinticuatro conejos neozelandeses machos fueron divididos al azar en cuatro grupos : 1) control, 2) infarto, 3) preacondicionamiento isquémico (PI) y 4) Hidrocortisona (HYD). El grupo HYD recibió 50 mg/kg de hidrocortisona 45 minutos antes de la isquemia mayor. Los niveles séricos de troponina cardíaca T (cTNT) y cortisol se midieron antes y después de los protocolos. Se utilizó la tinción cloruro de trifenil-tetrazolio para determinar el área infartada. En el presente estudio, la hidrocortisona exógena disminuyó el tamaño del infarto en un 53 por ciento en comparación con el grupo de infarto. Los niveles séricos de cortisol se incrementaron en los grupos IP y HYD, siendo significativa en el grupo de HYD (p <0,01). Un aumento en el nivel cortisol se asoció con la disminución del tamaño del infarto y la cTNT en los grupos IP y HYD (p> 0,01). En conclusión, hemos demostrado la hidrocortisona tiene efectos cardioprotectores cuando se inyecta antes de la aparición del infarto al miocardio. Además, hemos propuesto, por primera vez que la hidrocortisona endógena puede jugar un papel en los fenómenos de preacondicionamiento isquémico.
Subject(s)
Animals , Rabbits , Protective Agents/pharmacology , Heart , Reperfusion Injury/prevention & control , Hydrocortisone/pharmacology , Myocardial Infarction/prevention & control , Ischemic Preconditioning, Myocardial , Disease Models, Animal , Reperfusion Injury/drug therapy , Reperfusion Injury/blood , Hydrocortisone/blood , Myocardial Infarction/drug therapy , Myocardial Infarction/blood , Troponin T/bloodABSTRACT
Treatment of supraventricular arrhythmia includes a wide range of medical interventions. Herbal remedies are suitable alternatives to synthetic drugs due to their availability, minimal side effects and lower price. Pharmacological studies and traditional medical literature point to the cardiovascular effects of Citrus aurantium L. (Rutaceae) in many instances. In the present study we used isolated perfused AV-node of rabbit as an experimental model to determine the effect of various concentrations of essential oil of C. aurantium (0.1-0.3 v/v) on the nodal conduction time and refractoriness of an isolated rabbit AV-nodal preparations. Selective stimulation protocols were used to independently quantify AV nodal recovery, facilitation and fatigue in 18 rabbits. Our results showed concentration-dependent and rate-independent suppressive effects of essence of C. aurantium on the Wenchebach cycle length (WBCL), AV Conduction Time (AVCT) and effective and functional refractory periods (ERP & FRP). Functional properties such as facilitation and fatigue were significantly increased by this plant. Citrus aurantium plays a protective role against the toxic effects of ouabaine by increasing AV nodal conduction time and refractoriness. The above results indicated differential effects of C. aurantium on slow and fast pathways, with a dominant role on fast pathways. This research has explained the protective role of C. aurantium on ouabaine toxicity. All results indicated the potential anti-arrhythmic effects of C. aurantium in treating supraventricular tachyarrhythmia.
El tratamiento de la arritmia supraventricular incluye una amplia gama de intervenciones médicas. Los remedios herbarios son alternativas adecuadas a las drogas sintéticas debido a su disponibilidad, con escasos efectos secundarios y bajo precio. Estudios farmacológicos y la literatura médica tradicional señalan los efectos cardiovasculares de Citrus aurantium L. (Rutaceae) en muchos casos. En el presente estudio se usaron aislados perfundidos del nodo AV de conejo como modelo experimental para determinar el efecto de diferentes concentraciones de aceite esencial de C. aurantium (0,1-0,3 v/v) sobre en el tiempo de conducción nodal y refractariedad. Un protocolo de estimulación selectiva se utilizó para cuantificar de forma independiente la recuperación, la facilitación y la fatiga del nodo AV en 18 conejos. Nuestros resultados muestran efectos supresores dependientes de la concentración e independiente de la velocidad de la esencia de C. aurantium sobre la duración del ciclo Wenchebach (WBCL), tiempo de conducción AV (AVTC) y períodos refractarios eficaz y funcional (PRE y PRF). Propiedades funcionales tales como la facilitación y la fatiga se incrementaron de manera significativa por esta planta. La Citrus aurantium juega un papel protector contra los efectos tóxicos de ouabaína al incrementar el tiempo de conducción AV nodal y la refractariedad. Los resultados indican efectos diferenciales de C. aurantium sobre las vías lentas y rápidas, con un papel dominante en las vías rápidas. Esta investigación ha explicado el papel protector de C. aurantium sobre la toxicidad ouabaine. Todos los resultados indican los posibles efectos anti-arrítmicos de C. aurantium en el tratamiento de taquiarritmias supraventriculares.
Subject(s)
Animals , Rabbits , Oils, Volatile/pharmacology , Citrus/chemistry , Atrioventricular Node , Ouabain/antagonists & inhibitors , Arrhythmias, Cardiac/drug therapy , Cardiac Electrophysiology , Ouabain/toxicity , Plant Preparations/pharmacology , Time FactorsABSTRACT
Formaldehyde is used traditionally for fixing the cadaver, and vaporized during dissection and practical studying on cadaver. This study was designed to determine the histopathologic and morphometric changes of rat kidney while all of the experiments were exposed to formaldehyde for 18 weeks. 28 male albino Wistar rats were divided into the following three experimental groups (E1: 2hrs/d, 2d/w; E2: 2hrs/d, 4d/w; E3: 4hrs/d, 4d/w) and one control group (C). when the exposure period was expired the animals were anaesthetized with chloroform. After cervical dislocation, the abdomen was dissected and the kidneys were taken. The kidney specimens were sectioned and stained with Haematoxylin and Eosin technique for histologic and morphometric study. Data were obtained from an Olympus light microscope and the analyzed with spss (version 11.5) and ANOVA test. In all histopathology sections of groups E1, E2 and E3, these similar changes were seen: mild glumerolar congestion, focal congestion, and vacuolar degeneration of tubular cells. There were no evidences of inflammatory cells infiltration or fibrotic changes of interstitial tissue. Only mild, non-specific congestion was seen in cortical vessels. Also there were not any abnormalities in the staining of nucleus and cytoplasm. According to Morphometric study, Mean +/- SD of glomerulus's area in control, E1, E2 and E3 group were 10802.66 +/- 1038.18, 10759.50 +/- 1971.88, 10434.73 +/- 1763.76 and 10077.64 +/- 2068.78 micrometer, respectively. Mean +/- SD inner proximal tubule diameter in control, E1, E2 and E3 group were 16.16 +/- 2.49, 16.92 +/- 2.90, 16.31 +/-2.79 and15.66 +/-4.11 µm, respectively. Mean +/- SD of inner distal tubule diameter in control, E1, E2 and E3 group were 15.96 +/- 4.47, 16.20 +/- 1.66, 16.96 +/- 1.63 and17.45 +/- 3.26 µm, respectively. These differences were not significant between cases and control. This study showed that formaldehyde inhalation in 1.5 ppm can not make specific...
El formaldehído se utiliza tradicionalmente para la fijación de cadáveres y vaporiza durante la disección y los estudios prácticos en el cadáver. Este estudio fue diseñado para determinar los cambios histopatológicos y morfométricos de riñones de ratas expuestos al formaldehído, durante 18 semanas. 28 ratas albinas Wistar se dividieron en tres grupos experimentales (E1: 2 h/d, 2d/s, E2: 2 h/d, 4d/s; E3: 4 h/d, 4d/s) y un grupo control (C). Cuando el período de exposición se cumplió los animales fueron anestesiados con cloroformo. Después de la dislocación cervical, el abdomen fue disecado y se obtuvieron los riñones. Los especímenes de riñon fueron seccionados y teñidos con técnica hematoxilina y eosina para el estudio histológico y morfométrico. Los datos fueron obtenidos con un microscopio óptico Olympus, el análisis con el software SPSS (versión 11.5) y la prueba de ANOVA. En todas las secciones histopatológicas de los grupos E1, E2 y E3, se observaron cambios similares: congestión glumerular leve, congestión focal y degeneración vacuolar de las células tubulares. No hubo evidencias de la infiltración de células inflamatorias o cambios de tejido fibrótico intersticial. Sólo una leve congestión no específica fue observada en vasos corticales. Además no hubo anormalidad en la tinción del núcleo y el citoplasma. De acuerdo al estudio morfométrico, la Media +/- DS del área glomerular en los grupos control, E1, E2 y E3 fue 10802,66 +/- 1038,18, 10759,50 +/- 1971,88, 10434,73 +/-1763,76 y 10077,64 +/- 2068,78 µm, respectivamente. La Media +/- DS del diámetro interno del túbulo proximal en los grupos control, E1, E2 y E3 fueron 16,16 +/- 2,49, 16,92 +/- 2,90, 16,31 +/- 2,79 y 15,66 +/- 4,11 µm, respectivamente. La Media +/- SD del diámetro interno de los túbulos distales en los grupos control, E1, E2 y E3 fueron 15,96 +/- 4,47, 16,20 +/- 1,66, 16,96 +/- 1,63 y 17,45 +/- 3,26 µm, respectivamente. Estas diferencias no fueron significativas entre los casos...
Subject(s)
Male , Animals , Rats , Fixatives/pharmacology , Formaldehyde/pharmacology , Kidney , Kidney/pathology , Fixatives/toxicity , Formaldehyde/toxicity , Rats, WistarABSTRACT
Gaucher's disease is a rare lipid storage disorder, affecting one in 40,000-200,000 people and results from a genetic deficiency of the enzyme glucocerebrosidase (glucosylceramidase). We report a 10-year old Iranian girl with chief complaint of anemia from 8 years ago, managed for iron deficiency anemia. The patient had hepatomegaly associated with huge splenomegaly which was confirmed by sonography. No skeletal disorder was found. Bone marrow aspiration revealed typical Gaucher cells. Low level of beta-glucocerebrosidase enzyme activity confirmed the Gaucher disease. The patient is now under treatment with CEREZIME, a recombinant DNA modified form of glucocerebrosidase with good condition.
Subject(s)
Anemia/complications , Anemia/drug therapy , Gaucher Disease/diagnosis , Gaucher Disease/drug therapy , Hepatomegaly/diagnostic imaging , Bone Marrow Cells/pathology , Child , Female , Gaucher Disease/complications , Glucosylceramidase/genetics , Glucosylceramidase/therapeutic use , Humans , Recombinant Proteins/therapeutic use , Treatment Outcome , UltrasonographyABSTRACT
RESUMEN: Aunque la plasticidad neural muestra la capacidad del sistema nervioso para cambiar su estructura y función, lo cual es un hecho bien documentado, pocos estudios han mostrado la variación regional, dentro de la estructura del sistema nervioso central para sufrir cambios plásticos. A través de disecciones parasagitales, secuenciadas de medial a lateral, se estudió el grosor de la capa molecular, en el límite de la cisura primaria de hemisferio izquierdo del cerebelo, de ratas, con el propósito de evaluar las diferencias regionales en plasticidad. A pesar de la homogeneidad de la histología cerebelar, el estudio mostró que hay una diferencia interlobular significativa entre el grosor de la capa molecular en el límite de la fisura prima. Agregado a ello, fue revelado que los cambios de grosor tienen una tendencia significativa dentro de cada límite. La heterogeneidad cuantitativa de la arquitectura cerebelar, tal como la variación en el grosor cortical, puede proveer algunas evidencias que muestran que regiones diferentes de un corte homogéneo, aún de límites y áreas adyacentes dentro del mismo, pueden tener diferentes potenciales para plasticidad.
Subject(s)
Animals , Male , Rats , Cerebellum/anatomy & histology , Cerebellum/growth & development , Neuronal Plasticity/genetics , Rats, Wistar/anatomy & histology , Synaptic Transmission/geneticsABSTRACT
Formaldehyde is a chemical, which is used traditionally for fixing the cadaver. It is vaporized during dissection and practical studying on cadaver. Studies show that this vapor can cause some clinical symptoms such as throat, eye, skin and nasal irritation. This study was designed to determine the histopathologic changes of rat tracheal mucosa while all of the experiments were exposed to formaldehyde for 18 weeks. This study was performed on 28, 6-7 weeks postnatal albino Wistar rats. The rats were divided into 3 case groups (E1: 4h/d, 4d/w; E2: 2h/d, 4d/w; E3: 2h/d, 2d/w) and 1 control group. The tracheal specimens were sectioned and stained with H&E technique for histopathologic study. An epithelial disorganization, cilia disappearance, slight dysplastic changes and slight subepithelial lymphocytic infiltration were observed in the case of E1. Epithelial disorganization, irregular cilia and slight subepithelial infiltration were seen in E2 and E3 groups. The results of this study show that "the more exposure to formaldehyde vapor, the more intense epithelial changes".
El formaldehido es un producto químico que se usa tradicionalmente para la fijación de cadáveres. Éste se vaporiza durante la disección y los estudios prácticos en el cadáver. Investigaciones han mostrado que este vapor puede causar algunos síntomas clínicos como la irritación de garganta, ojos, piel y mucosa nasal. Este estudio tuvo como objetivo determinar los cambios histopatológicos en la mucosa de la tráquea de la rata para lo cual todos los animales fueron expuestos al formaldehído, durante 18 semanas. El estudio fue realizado en 28 ratas albinas Wistar, con 6-7 semanas de vida. Las ratas fueron divididas en 3 grupos (E1: 4h/día, 4días/semana; E2: 2h/día, 4días/semana; E3: 2h/día, 2días/semana) y un grupo control. Fueron seccionadasas las tráqueas de los especímenes y teñidas con H&E para su estudio histopatológico. Una desorganización epitelial, desaparición de cilios, leves cambios dispásticos y leve infiltración linfocítica subepiteial fueron observados en el grupo E1. Desorganización epitelial, cilios irregulares y leve infiltración subepitelial fueron observados en los grupos E2 y E3. Los resultados de este estudio muestran que a mayor exposición al vapor del formaldehido, más intensos son los cambios epiteliales de la mucosa traqueal.