Molecular Bases of Protein Antigenicity and Determinants of Immunogenicity, Anergy, and Mitogenicity.

BACKGROUND: The immune system is able to recognize substances that originate from inside or outside the body and are potentially harmful. Foreign substances that bind to immune system components exhibit antigenicity and are defined as antigens. The antigens exhibiting immunogenicity can induce innate or adaptive immune responses and give rise to humoral or cell-mediated immunity. The antigens exhibiting mitogenicity can cross-link cell membrane receptors on B and T lymphocytes leading to cell proliferation. All antigens vary greatly in physicochemical features such as biochemical nature, structural complexity, molecular size, foreignness, solubility, and so on. OBJECTIVE: Thus, this review aims to describe the molecular bases of protein-antigenicity and those molecular bases that lead to an immune response, lymphocyte proliferation, or unresponsiveness. CONCLUSION: The epitopes of an antigen are located in surface areas; they are about 880-3,300 Da in size. They are protein, carbohydrate, or lipid in nature. Soluble antigens are smaller than 1 nm and are endocytosed less efficiently than particulate antigens. The more the structural complexity of an antigen increases, the more the antigenicity increases due to the number and variety of epitopes. The smallest immunogens are about 4,000-10,000 Da in size. The more phylogenetically distant immunogens are from the immunogen-recipient, the more immunogenicity increases. Antigens that are immunogens can trigger an innate or adaptive immune response. The innate response is induced by antigens that are pathogen-associated molecular patterns. Exogenous antigens, T Dependent or T Independent, induce humoral immunogenicity. TD protein-antigens require two epitopes, one sequential and one conformational to induce antibodies, whereas, TI non-protein-antigens require only one conformational epitope to induce low-affinity antibodies. Endogenous protein antigens require only one sequential epitope to induce cell-mediated immunogenicity.

Tannic Acid Exhibits Adjuvant Activity by Enhancing Humoral and Cell-Mediated Immunity Against BSA as a Protein Antigen.

BACKGROUND: Immunization or vaccination is the process of inducing artificial immunity against an antigen taking advantage of the mechanisms of immunological memory. Current vaccines include substances known as adjuvants, which tend to improve the immunogenicity of the antigen, reduce the antigen quantity employed, and boost the immune response in weak responders. Unfortunately, only a few vaccine adjuvants are approved for human use. OBJECTIVE: Thus, the objective of this study was to investigate the effect of Tannic acid on humoral and cell-mediated immunity against bovine serum albumin (BSA) as a protein antigen in Wistar rats. METHODS: In order to establish the Tannic acid concentration to test it as an adjuvant, the lethal dose 50 and maximum non-toxic dose were calculated through cytotoxicity and hemolytic assays with J774 A.1 cell line and rat erythrocytes by resazurin reduction method and UV/vis spectrophotometry. Thirty Wistar rats were divided into 5 groups that included two controls without antigen and three treatment groups of adjuvants plus BSA as a protein antigen. The rats were immunized in a 30-day scheme. Blood samples were collected for humoral immunity analysis by means of immunoglobulin quantification, isotyping and antigen-antibody precipitation inhibition analysis. Rat peritoneal macrophages and splenocytes were isolated for cell-mediated immunity analysis by means of nitric oxide quantification from adjuvant stimulated peritoneal macrophages and lymphocytes proliferation assay. RESULTS: Tannic acid was capable of increasing the immunogenicity of the antigen; besides, it was able to stimulate cell-mediated immunity by means of increased lymphocyte proliferation. Moreover, Tannic acid improved the humoral response by means of increased specific antibodies titers. These activities may be attributed to pattern recognition receptors stimulation. CONCLUSION: Tannic acid was considered biocompatible when tested in vivo because the concentration tested did not show cytotoxicity or hemolytic effect, and there was no detrimental effect observed on the animals' health. These results show Tannic acid as a promising candidate for vaccine adjuvant.

Neuropathic or systemic chronic intoxication with Karwinskia humboldtiana (Buckthorn) fruit? Histopathological effect in myocardial and skeletal muscle.

In accidental intoxicated animals and humans, Karwinskia humboldtiana (Kh) causes lesions in the central and peripheral nervous system and organs like the kidney, liver, and lung. The objective was to evaluate the histology of myocardium and skeletal muscle after experimental chronic intoxication with mature fruit of Kh in Wistar rat. Twenty-five rats were used and divided into five groups (n = 5): four intoxicated and one control. Kh fruit was ground, dried, sieved, and administered by an orogastric tube. Intoxicated rats received 3.5 g/kg body weight fractionated in 5 doses. Control rats received only water. Animals were euthanized at 24, 48, 58, and 112 days, respectively. Samples of the myocardium and skeletal muscle were obtained and processed for light microscopy evaluation. Morphological analyses were performed, including a microdensitometric analysis. Results showed areas of necrosis in the muscle fibers, fibers with vacuolated cytoplasm, and disorganization of myofilaments, as well as staining variations in both myocardium and skeletal muscle time-depending. Zones with loss of continuity of the external lamina were identified with PAS with the diastase histochemical method. Immunolabeling with specific antibodies demonstrated diminution of actin and desmin myofilaments. The microdensitometric analysis showed a statistically significant difference between the intoxicated vs control group. These findings demonstrate that chronic intoxication of Kh fruit also causes damage in myocardial and skeletal muscle, these alterations will be useful to understand that the toxic effects of Kh fruit in accidently intoxicated humans are systemic, and not only over the nervous system.

Cranial bone regeneration with collagen type I and polyvinylpyrrolidone (Fibroquel®) combined with hyaluronic acid in Wistar rats: morphological study / Regeneración ósea craneal con colágeno tipo I y polivinilpirrolidona (Fibroquel®) combinado con ácido hialurónico en ratas Wistar: estudio morfológico

SUMMARY: The purpose of this study was to evaluate by morphological methods, if a mixture of Fibroquel® and hyaluronic acid implanted in an animal model of cranial bone injury could promote bone regeneration. 12 Wistar rats were divided in three groups, control group, bone injury without treatment and bone injury with treatment. After experimental period, bone samples were taken and stained with H & E, Masson trichrome, PAS-D, immunohistochemistry with anti-PCNA monoclonal antibody and applied a semiquantitative morphometric method. Treatment group showed extensive areas of collagen fibers in contact with normal bone tissue, areas of normal histology, PAS positive material and less cellular proliferation. We demonstrated for the first time that a mixture of Fibroquel® and hyaluronic acid implanted in an animal model of cranial bone injury promotes bone regeneration.

RESUMEN: El propósito de este estudio fue evaluar por métodos morfológicos, si una mezcla de Fibroquel® y ácido hialurónico implantado en un modelo animal de lesión del hueso craneal podría promover la regeneración ósea. Se dividieron 12 ratas Wistar en tres grupos, grupo control, lesión ósea sin tratamiento y lesión ósea con tratamiento. Después del período experimental, se tomaron muestras de hueso y se tiñeron con H & E, tricrómico de Masson, PAS-D, inmunohistoquímica con anticuerpo monoclonal anti-PCNA y se aplicó un método morfométrico semicuantitativo. El grupo de tratamiento mostró áreas extensas de fibras de colágeno en contacto con tejido óseo normal, áreas de histología normal, material PAS positivo y menor proliferación celular. Demostramos por primera vez que una mezcla de Fibroquel® y ácido hialurónico implantado en un modelo animal de lesión del hueso craneal promueve la regeneración ósea.

Insights from Pharmaceutical Biotechnology into Phenolic Biopharmaceuticals against COVID-19.

BACKGROUND: The COVID-19 pandemic had infected more than 3.5M people around the world and more than 250K people died in 187 countries by May 2020. The causal agent of this disease is a coronavirus whose onset of symptoms to death range from 6 to 41 days with a median of 14 days. This period is dependent on several factors such as the presence of comorbidities, age and the efficiency of the innate or adaptive immune responses. METHODS: The effector mechanisms of both types of immune responses depend on the pathogen involved. In the case of a viral infection, the innate immune response may approach the harmful virus through pattern recognition receptors inducing an antiviral state. RESULTS: On the other hand, the adaptive immune response activates antibody production to neutralize or eliminate the virus. Phenolics are plant secondary metabolites with many biological activities for plants and humans against infection. Chemical modification of proteins may enhance their biological properties; thus, a protein of medical interest, for instance, a viral protein can be used as a scaffold to build a biopharmaceutical conjugated or complexated with phenolics exhibiting structural complexity or biological activities to achieve effective phenolic-protein-based therapeutics like vaccine adjuvant complexes, immunogen conjugates, and antiviral conjugates. CONCLUSION: Pharmaceutical biotechnology applies the principles of biotechnology to develop biopharmaceuticals for protein-based therapeutics; such as adjuvants, recombinant proteins, monoclonal antibodies, and antivirals. As neither a vaccine nor a treatment for COVID-19 is currently available, this manuscript focuses on insights from pharmaceutical biotechnology into phenolic biopharmaceuticals against COVID-19.

Differential expression of mast cell granules in samples of metastatic and non-metastatic colorectal cancer in patients.

Various cell types participate in the tumor process, in which the mast cells have been described; however, the role they play in colorectal adenocarcinoma has not yet been fully understood. Therefore, the present work aimed to compare employing histochemistry and immunohistochemistry, the number of mast cells and the content of some cytoplasmic granules in moderately differentiated non-metastatic and metastatic colorectal adenocarcinoma, analyzing tissue samples from patients. Histochemical techniques with Toluidine Blue (TBO), Periodic Schiff Acid (PAS), Alcian Blue/Periodic Acid-Schiff (PAB) and Alcian Blue/Safranin (ABS); as well as immunohistochemical reactions with anti-antibodies anti-Tryptase and anti-Chymase were applied to quantify total mast cells and content of some cytoplasmic granules. Statistical analysis was performed using SPSS V22.0 software (p ≤ 0.05). The degree of positivity of the reaction and degranulation of mast cells was reported in percentages. In our results, we observed that there are differences in the quantity and histochemical composition of the granules of mast cells (metastatic group PAS and ABS comparing the TBO reaction), as well as in the immunohistochemical composition between Tryptase and Chymase and the number of degranulated cells in both study groups (74 % degranulated mast cells in the metastatic group, 66 % integrate mast cells in the non-metastatic group). Therefore, we consider that the differences may be some of the probable factors that lead to metastasis of colorectal adenocarcinoma.

All-trans retinoic acid improves pancreatic cell proliferation on induced type 1 diabetic rats.

All-trans retinoic acid (ATRA) has been extensively studied as an integrating component of endocrine functions in the pancreas. The aim of this study was to evaluate the effects of ATRA on physiopathological biomarkers in an experimental model of rat with type 1 diabetes induced by alloxan (T1D). Twenty Wistar rats were divided equally into five groups, each receiving a different treatment: a control group (CG), a diabetic group without T1D treatment, a diabetic group treated with ATRA, a diabetic group supplemented with vitamin E (VIT E), and a group that was given olive oil (V). The administration of ATRA for 17 days produced a significant reduction in weight and glucose levels, compared to the T1D and VIT E groups. The evaluation of total antioxidant capacity (TAC) and lipoperoxidation showed no relevant difference among the groups. The results of the histological analysis showed similarities both in the size and in the number of islets of Langerhans in the pancreatic tissue obtained from the ATRA group and the CG. ATRA displayed a significant reduction of glycemic values in diabetic rats. Ultrastructurally, ß-cells, acinar, and ductal cells restored their normal appearance. ATRA can contribute to the recovery of pancreatic damage due to alloxan induction. It seems that the antioxidant effect of ATRA is not responsible for the differences observed.

Evaluación de la respuesta inflamatoria en ratas Wistar a TheraCalTM LC implantado vía subcutánea / Evaluation of the inflammatory response in Wistar rats to TheraCalTM LC implanted subcutaneously

El Theracal TM LC es un cemento silicato de calcio (Ca) modificado con resina (SMCR) que ha demostrado ser un material ideal para el tratamiento dentino-pulpar por su alta tasa de formación de calcio. Los biomateriales por su contenido de Ca tienden a tener un aumento en su biodisponibilidad, estimulando la formación del puente dentario atreves de las células involucradas en la formación de tejidos mineralizados, promoviendo la diferenciación de fibroblastos en odontoblastos y aumentando la actividad de la enzima pirofostasa responsable en la mineralización de la dentina. El presente estudio con el objetivo de evaluar la respuesta inflamatoria a Theracal TM LC subcutáneamente en ratas Wistar. Fueron usados seis ratas cepa Wistar en las cuales se realizaron cuatro bolsillos quirúrgicos subcutáneos. Cada uno de estos bolsillos se determinó como cuadrante distinto, conteniendo los siguientes implantes: 1 Theracal TM LC en tubo polietileno, 2 tubo de polietileno, 3 Theracal TM LC directo y 4 como control. Las muestras histológicas se procesaron y se evaluaron distintos tipos celulares mediante conteo a microscopio de luz a 100X utilizando las tinciones H&E y AT pH 2.3. Los resultados mostraron que existen diferencias significativas en todos los tipos celulares observados durante los diferentes tiempos de exposición. Las diferencias en los tipos celulares observados podrían ser debido al tiempo de exposición al Theracal TM LC, al tubo polietileno y a ambos. El tejido evaluado del implante del tubo polietileno y al tubo polietileno con Theracal TM LC, presentan mayor respuesta inflamatoria, a diferencia en el tejido implantado con Theracal TM LC directamente.

TheraCalTM LC is a resin-modified calcium silicate (Ca) resin (SMCR) that has proven to be an ideal material for dentin-pulp treatment due to its high rate of calcium formation. Biomaterials due to their Ca content tend to have an increase in their bioavailability, stimulating the formation of the dental bridge through the cells involved in the formation of mineralized tissues, promoting the differentiation of fibroblasts in odontoblasts and increasing the activity of the pyrophosphate enzyme responsible in dentin mineralization. The present study aimed to evaluate the inflammatory response to TheracalTM LC subcutaneously in Wistar rats. Six Wistar strain rats were used in which four subcutaneous surgical pockets were made. Each of these pockets was determined as a different quadrant, containing the following implants: 1 TheracalTM LC in polyethylene tube, 2 polyethylene tubes, 3 TheracalTM LC direct and 4 as control. The histological samples were processed, and different cell types were evaluated by light microscopy at 100X using the H&E and AT pH 2.3 stains. The results showed that there are significant differences in all cell types observed during the different exposure times. The differences in the cell types observed could be due to the exposure time to TheracalTM LC, to the polyethylene tube and to both. The evaluated tissue of the polyethylene tube implant and the polyethylene tube with TheracalTM LC present a greater inflammatory response, unlike in the tissue implanted with TheracalTM LC directly.

Evaluación de la actividad antioxidante de Cnidoscolus chayamansa (Chaya), Euphorbia prostrata (Hierba de la Golondrina) y Jatropha dioica (Sangre de Drago) en ratas Wistar inducidas a hiperglicemia / Evaluation of the antioxidant activity of Cnidoscolus chayamansa (Chaya), Euphorbia prostrata (Herb of the Swallow) and Jatropha dioica (Drago blood) in Wistar rats induced to hyperglycemia

RESUMEN: Estudios recientes han demostrado que los compuestos activos presentes en extractos de C. chayamansa, E. prostrata y J. dioica tienen propiedades antioxidantes. Los resultados obtenidos en nuestro estudio fueron compuestos fenólicos solubles mostraron en C. chayamansa 6,34, E. prostrata 10,67, J. dioica 1,83 mg equiv de ácido gálico/gm BS respectivamente. Los antioxidantes solubles en agua por el método ABTS fueron para C. chayamansa 5.9, E. prostrata 12.7 y para J. dioica 2.5 mM equiv. de trolox/gr BS. Los resultados histopatológicos muestran una mejoría en los tejidos tratados con los extractos después de la inducción a hiperglicemia.

SUMMARY: Recent studies have shown that the active compounds present in extracts of C. chayamansa, E. prostrata and J. dioica have antioxidant properties. The results obtained in our study were soluble phenolic compounds showed in C. chayamansa 6.34, E. prostrata 10.67, J. dioica 1.83 mg equiv of gallic acid/gm BS respectively. The antioxidants soluble in water by the ABTS method were for C. chayamansa 5.9, E. prostrata 12.7 and for J. dioica 2.5 mM equiv. of trolox/gr BS. The histopathological results show an improvement in the tissues treated with the extracts after the induction to hyperglycemia.

Peroxisomicine A1 (toxin T-514) induces cell death of hepatocytes in vivo by triggering the intrinsic apoptotic pathway.

Karwinskia parvifolia possesses the highest concentration levels of the anthracenone T-514 (PA1). Studies have demonstrated the induction of apoptosis by PA1 in cancer cell lines. The aim was to investigate the effects of PA1 on the apoptosis of the mouse liver in vivo and its underlying pathway. Sixty CD-1 mice were divided into three groups: untreated, vehicle, and treated with PA1. The animals were euthanized at 4, 8, 12, and 24 h post-treatment. To confirm the toxic effect of PA1 we determined the activity of catalase. Liver sections were prepared for morphological examination and for immunohistochemical evaluation of anti and pro-apoptotic markers. DNA fragmentation was detected by TUNEL assay and electrophoresis. Pre-apoptotic mitochondrial alterations and cytochrome c oxidase activity were analyzed by transmission electron microscopy. PA1 induced pre-apoptotic mitochondrial alterations, a high activity of the cytochrome oxidase, and apoptosis in hepatocytes. PA1 caused p53 over-expression and down regulation of PCNA. PA1 also increased the expression levels of the pro-apoptotic markers Bax and Bak, whereas the anti-apoptotic molecule Bcl-2 was decreased. PA1 induces apoptosis by activating the intrinsic mitochondrial apoptotic pathway. These results will be useful for studies regarding the use of PA1 as an antineoplastic agent.

The matrix synthesis and anti-inflammatory effect of autologous leukocyte-poor platelet rich plasma in human cartilage explants.

OBJECTIVE: To determine the effects of autologous leukocyte-poor platelet-rich plasma (LP-PRP) on the expression of markers involved in cartilage-extracellular matrix production and inflammation in cartilage explants bearing osteoarthritis. MATERIALS AND METHODS: Cartilage explants and LP-PRP were obtained from 10 patients who underwent total knee arthroplasty. The explants were cultured in spinner flasks for 28 days in the presence of interleukin (IL)-1ß and/or LP-PRP. The gene expression of catabolic (MMP13, ADAMTS5, and IL1ß) and anabolic factors (COL2A1, ACAN, and SOX9) was quantified. A histological assessment was performed according to a modified Mankin score, and quantification of type II and I collagen deposition. RESULTS: The gene expression of catabolic factors and the Mankin score were lower in LP-PRP- and LP-PRP/IL-1ß- than in IL-1ß-treated explants, suggesting less matrix degradation in explants cultured in the presence of LP-PRP. Higher expression of genes involved in cartilage matrix restoration was observed in LP-PRP and LP-PRP/IL-1ß- when compared to IL-1ß-treated explants. The explants treated with LP-PRP and LP-PRP/IL-1ß exhibited a higher deposition of type II collagen as well as a lower deposition of type I collagen and also better surface integrity and a significant increase in the number of chondrocytes. CONCLUSION: LP-PRP treatment favored restoration in early osteoarthritic cartilage and reduced the pro-inflammatory effect of IL-1ß. LP-PRP is a promising therapy for early osteoarthritis, as it promotes extracellular matrix repair, reduces inflammation, and slows cartilage degeneration.

Invasion of TC-1 cells to skeletal muscle fibers protect them from peroxisomicine A1 (T-514) treatment in a murine model of cancer.

T-514 or Peroxisomicine A1 (PA1) is a toxin isolated from plants of genus Karwinskia. In vitro studies described selective toxicity of PA1 on malignant cell lines. A toxic effect of PA1 on TC-1 cells in vivo was reported. The objective was to evaluate the effect of PA1 over invasion of TC-1 cells to muscle fibers in vivo. TC-1 cells were implanted in 36 mice divided in two groups (n: 18): treated with PA1 or with vehicle, a control group was included. At 10 days, nine mice of each group were euthanized. TC-1 implant site was analyzed by light and electron microscopy, a morphometric study was also performed. Remaining mice were used to evaluate tumor growth and survival time. Results show tumor cells between muscle fibers, with diminution in diameter, change in the staining pattern, loss of continuity of external lamina, and sarcoplasm with tumor cells. Statistically difference was observed between treated group vs control group. PA1 decreased tumor growth and increased the survival time in treated mice. The degree of resistant activity, aggressiveness, and invasiveness of TC-1 cells described in present work; should be taken into account in studies that evaluate effectiveness of therapies using this cancer model.

El extracto acuoso de ruta graveolens del norte de méxico causa apoptosis y muestra efecto antiproliferativo sobre el hígado de rata wistar: evidencia morfológica / Aqueous extract of ruta graveolens from the north of mexico causes apoptosis and shows antiproliferative effect on the liver of wistar rat: morphological evidence

Ruta graveolens es una planta nativa del Mediterráneo Oriental y del área Sur Occidental de Asia, de esta planta se han aislado más de 120 compuestos químicos. En un estudio previo en nuestro laboratorio se observó que un extracto acuoso de R. graveolens causó necrosis y alteraciones morfológicas sugestivas de apoptosis sobre el hígado de rata Wistar. El objetivo del presente estudio, fue evaluar la inducción de apoptosis y el posible efecto antiproliferativo in vivo de un extracto acuso de R. graveolens del norte de México, mediante métodos inmunohistoquímicos. Se utilizaron 25 ratas Wistar y se dividieron en 5 grupos (n=5). El grupo 1 correspondió al grupo control negativo, el grupo 2 o control positivo se trató con 100 mg de dexametasona/kg/día. Los grupos 3 y 4 se trataron con 30 y 100 mg de extracto de R. graveolens/kg/día respectivamente. Al grupo 5 se le administraron 100 mg de dexametasona/kg/día combinados con 100 mg de extracto de R. graveolens/kg/día. Las administraciones se realizaron vía intraperitoneal por tres días. Los animales se sacrificaron por dislocación cervical, y se tomaron muestras de hígado que se fijaron en formalina, posteriormente se incluyeron en bloques de parafina. Se obtuvieron cortes histológicos que se tiñeron con el método tricrómico de Masson. También se realizaron pruebas inmunohistoquímicas de TUNEL, anti-bcl-2 y anti-PCNA; además de un estudio morfométrico. Los resultados demuestran por primera vez el potencial apoptósico y antiproliferativo del extracto acuoso de R. graveolens del norte de México, sobre el hígado de rata Wistar. Se sugiere la posibilidad de emplear dosis menores a las administradas en este estudio del extracto acuoso de R. graveolens, para investigar su potencial uso como agente antineoplásico en estudios in vitro con líneas celulares tumorales e/o implantadas en modelos murinos de cáncer.

Ruta graveolens, is a native plant of the Eastern Mediterranean and the South Western area of Asia. From this plant, more than 120 chemical compounds have been isolated. In a previous study in our laboratory, we observed that an aqueous extract of R. graveolens, caused necrosis and morphological alterations suggestive of apoptosis on the liver of Wistar rats. The objective of this study, was to evaluate the induction of apoptosis and a possible antiproliferative effect in vivo of an aqueous extract of R. graveolens from the north of Mexico, by immunohistochemical methods. 25 Wistar rats were used and divided into 5 groups (n= 5). Group 1 corresponded to negative control group, group 2 or positive control was treated with 100 mg of dexamethasone/kg/day. Groups 3 and 4 were treated with 30 and 100 mg of extract of R. graveolens/kg/day respectively. Group 5 received the administration of 100 mg of dexamethasone/kg/day combined with 100 mg of extract of R. graveolens/kg/day. The administrations were by intraperitoneal via for three days. The animals were sacrificed by cervical dislocation, liver samples were taken, fixed in formalin and then samples were embedded in paraffin blocks. Histological sections were obtained and stained with Masson trichrome method. Immunohistochemical assays of TUNEL, anti-bcl-2, and anti-PCNA were performed. Also a morphometric study was carried out. Results show for the first time the potential apoptotic and antiproliferative effect of an aqueous extract of R. graveolens from the north of Mexico on the liver of Wistar rats. This suggests the use of lower doses of the extract of R. graveolens, to investigate its potential use as an antineoplastic agent, in studies in vitro with tumor cell lines and/or implanted in murine models of cancer.

Intoxicación crónica con el fruto maduro de karwinskia humboldtiana en ratas wistar: daño renal / Chronic intoxication with ripe fruit of karwinskia humboldtiana in wistar rats: renal damage

Karwinskia humboldtiana (Kh) es un arbusto venenoso responsable de numerosos casos de intoxicación accidental en humanos. En la literatura se ha descrito a la intoxicación crónica con Kh como uno polineuropatía sin describir si existen o no alteraciones en órganos distintos al SNC y SNP como lo es el riñón. El objetivo de este estudio fue evaluar la morfología renal en un modelo de intoxicación crónica con Kh. Se utilizaron 32 ratas Wistar, se dividieron en cuatro grupos (n=8) en donde 5 ratas de cada grupo fueron intoxicadas y 3 fueron control no intoxicadas. A las ratas intoxicadas se les administraron por vía oral 3,5 g/kg del fruto seco y molido de Kh fraccionados en 5 dosis de 1,5; 0,5; 0,5; 0,5 y 0,5 g/kg los días 0, 3, 7, 10 y 14 respectivamente. Las ratas control solo recibieron agua. Cada grupo fue sacrificado a diferentes tiempos según la evolución de la parálisis. Se obtuvieron muestras de riñón, se procesaron hasta obtener bloques de parafina y resinas epóxicas, se obtuvieron cortes y se tiñeron y contrastaron para su observación al microscopio de luz y electrónico de transmisión (MET) respectivamente. A microscopia de luz identificamos congestión vascular, necrosis de los túbulos contorneados y fibrosis de la cápsula de renal, en la etapa de parálisis se realizo un conteo de los glomérulos afectados en las muestras tratadas con Kh, a MET además de los hallazgos previamente descritos se identificó la presencia de abundantes depósitos de matriz extracelular en la membrana basal de la cápsula renal y en la barrera de filtración de todos los grupos intoxicados, siendo más evidentes en el grupo de recuperación, lo que demuestra que la intoxicación crónica con Kh es una intoxicación sistémica y no exclusiva del SNC y SNP.

Karwinskia humboldtiana (Kh) is a poisonous shrub causing a number a accidental intoxications in humans. In previous studies, damage has been reported to Peripheral and Central Nervous System. Main intoxication sign is the presence of paralysis. However, no studies have been documented about damage to other organs like the kidney. The objective of this research is to evaluate kidney histology during chronic intoxication. Thirty two (32) Wistar rats were divided into 4 groups (n=8). For each group, 5 rats were intoxicated with Kh and 3 received water only as a control. Intoxicated rats received 3.5 g/Kg body weight of dry powder of Kh fruit, fractionated in 5 doses as follows 1.5, 0.5, 0.5, 0.5, 05 on days 0, 3, 7, 10 and 14 respectively. Control rats received water only. Each group was euthanized at different times during paralysis evolution. Samples of kidney were obtained and processed by routine technique until paraffin embedding for light microscopy studies, and in epoxy resins for transmission electron microscopy. Sections were obtained and stained with H&E, Masson's trichrome, and treated for PAS with diastase reaction to demonstrate basal membranes. At the light microscopic level we observed blood vessel congestion, tubular necrosis and fibrosis of renal capsule. Both at Light microscopy and electron microscopy, it was identified a thickening of the filtration barrier and of renal capsule, in all intoxicated animals, especially in the recovery group. These findings demonstrate that Kh causes a systemic intoxication and not only of the nervous system, as has been considered up to now.

Efecto tóxico del extracto acuoso de ruta graveolens del norte de mexico sobre el hígado de rata wistar / Toxic effect of aqueous extract of ruta graveolens from the north of mexico on the liver of wistar rat

A Ruta graveolens se le atribuyen propiedades benéficas en medicina tradicional, sin embargo se ha demostrado que también puede producir efectos adversos. A la fecha no existe evidencia que ratifique que R. graveolens es totalmente inofensiva, por este motivo el objetivo de este estudio fue determinar el efecto tóxico del extracto acuoso de las hojas de esta especie vegetal en hígado de rata. Se utilizaron 25 ratas Wistar y se dividieron en 5 grupos (n=5). El grupo 1 correspondió al grupo control negativo, el grupo 2 o control positivo se trató con 100 mg de dexametasona/kg/día. Los grupos 3 y 4 se trataron con 30 y 100 mg de extracto de R. graveolens respectivamente. Al grupo 5 se le administraron 100 mg de dexametasona/kg/día combinado con 100 mg de extracto de R. graveolens/kg/día. Las administraciones se realizaron vía intraperitoneal por tres días. Los animales se sacrificaron por dislocación cervical. Las muestras de hígado se fijaron en formalina y posteriormente se incluyeron en parafina. Se obtuvieron cortes histológicos de 5 micras de grosor que se tiñeron con Hematoxilina-Eosina para la evaluación histológica con microscopia de luz. Los resultados demuestran por primera vez que la exposición al extracto acuoso de R. graveolens induce alteraciones morfológicas en el hígado de ratas Wistar. Estas alteraciones se observaron de manera leve en el grupo 3 y se incrementaron en el grupo 4. Destacó que el mayor daño se observó en el grupo 5. Se concluye que el extracto acuoso de R. graveolens resultó tóxico, sin embargo es necesario realizar estudios adicionales con el fin de caracterizar otros efectos toxicológicos que soporten el riesgo del uso de R. graveolens en medicina tradicional a largo plazo.

In traditional medicine, beneficial properties are attributed to Ruta graveolens, but it has been shown that it can also cause side effects. Because there is no evidence that ratifies that R. graveolens is totally harmless. The aim of this study was to determine the toxic effect of aqueous extract of the leaves of this plant in rat liver. 25 Wistar rats were used and divided into 5 groups (n = 5). Group 1 corresponded to the negative control group; group 2 or positive control was treated with 100 mg of dexamethasone/kg/day. Groups 3 and 4 were treated with 30 and 100 mg of extract of R. graveolens respectively. Group 5 was treated with 100 mg dexamethasone/kg/ day in combination with 100 mg of extract of R. graveolens/kg/day. Administrations were performed intraperitoneally for three days. All animals were sacrificed by cervical dislocation. Liver samples were fixed in formalin and then embedded in paraffin. Histological sections were obtained from 5 microns thick and stained with hematoxylin-eosin for histological evaluation by light microscopy. The results demonstrate for the first time that exposure to aqueous extract of R. graveolens induces morphological changes in the liver of Wistar rats. These alterations were observed slightly in group 3. Alterations increased in group 4. Highest damage was observed in group 5. The aqueous extract of R. graveolens was toxic; furthermore additional studies are needed to characterize other toxicological effects that support the risk of use of R. graveolens in traditional medicine in a long term.

Células cebadas y sus patrones de expresión del receptor c-kit (CD117) como probables indicadores de metástasis en el adenocarcinoma de mama en humanos / Mast cells and expression patterns of c-kit (CD117) receptor as probable indicators of metastases in human breast adenocarcinoma

El adenocarcinoma de mama es la segunda neoplasia maligna más común en mujeres, solo después del cáncer de pulmón. Este tumor se clasifica histopatológicamente en bien, moderado y poco diferenciado. Además de esta clasificación, los análisis actuales utilizan inmunohistoquímica para identificar receptores hormonales para estrógenos y progesterona (RH) y HER2/neu, esta información permite hacer un pronóstico de respuesta al tratamiento y tiempo de sobrevida. Las células cebadas se han asociado a un mal pronóstico, ya que participan en la angiogénesis y el crecimiento tumoral favoreciendo la metástasis. Esto disminuye la esperanza de vida. También las células cebadas expresan en la membrana plasmática el receptor c-Kit (CD117) que se ha asociado a proliferación celular. En este estudio, se evaluó si existen variaciones en los patrones de expresión de c-Kit en las células cebadas presentes en muestras de adenocarcinoma de mama; y si los distintos patrones del receptor se asocian a la presencia de metástasis linfática. Se utilizaron muestras de adenocarcinoma moderadamente diferenciado, y se analizaron empleando métodos histológicos, histoquímicos e inmunohistoquímicos. Los grupos se clasificaron de acuerdo a su positividad a RH y HER2/neu, y se subclasificaron de acuerdo a la presencia o no de metástasis. Además se realizó un análisis morfométrico de células cebadas y los patrones de expresión de c-Kit. Los grupos con metástasis mostraron mayor cantidad de células cebadas comparados con el grupo control, y su grupo correspondiente sin metástasis. Las células cebadas con patrones de expresión 1 y 3 fueron más abundantes en los grupos con metástasis. En los grupos sin metástasis predominaron las células cebadas con el patrón 2. Los resultados sugieren que el número de células cebadas y los patrones de expresión de c-Kit, podrían ser empleados como indicadores probables, más no definitivos de la presencia de metástasis linfática.

Breast adenocarcinoma is the second most common neoplasm, just after lung cancer in women. According to histopathological features this tumor is classified into well, moderate and poorly differentiated. In addition to this classification, current analysis also use immunohistochemistry to detect estrogen and progesterone receptors (RH), and HER2/neu, this information is useful to make a prognostic in treatment response and survival time. Mast cells have been associated with bad prognosis, because they participate in angiogenesis and tumor growth promoting metastases. This decreases life expectancy. Also mast cells express in the plasmatic membrane the receptor c-Kit (CD117) that is associated to cell proliferation. In this study, we evaluated if there are variations in the expression patterns of c-Kit receptor in mast cells present in breast adenocarcinoma samples; and if expression patterns are associated with the presence of metastases to ganglion. Samples of moderately differentiated adenocarcinoma were evaluated using histological, histochemistry and immunohistochemistry methods. Groups were classified according to their positivity to RH and HER2/neu, and subclassified if presented or not metastases. Also mast cells and expression patterns of c-Kit receptor were analyzed by a morphometric method. Groups with metastases showed higher amount of mast cells, compared with control group and their corresponding group without metastases. Mast cells with expression patterns 1 and 3 were more abundant in all the groups with metastasis. In groups without metastases mast cells with pattern 2 were predominant. Results suggest that the amount of mast cells and the expression patterns of c-Kit could be use as probable indicators, but not definitive of the presence of nodal metastases.

Alteraciones morfológicas en el tracto respiratorio de ratas Wistar inducidas por vapores de la raíz de hierba del zorrillo (Petiveria alliacea) del suroeste de México / Morphologic alterations in the respiratory tract of Wistar rats induced by steams of the root of hierba del zorrillo (Petiveria alliacea) from southwest of Mexico

Petiveria alliacea, es conocida con diferentes nombres según el lugar donde se le encuentre. Estudios con hojas, tallo, raíz o extractos describen múltiples usos medicinales. Sin embargo, son pocos los que describen efectos tóxicos. En este estudio se evaluó el efecto morfológico de los vapores de la raíz de P. alliacea sobre el tracto respiratorio de ratas Wistar. Se emplearon 15 ratas divididas en 5 grupos (n=3): control absoluto, 0, 5, 15 y 30 minutos post-exposición (grupos I-V, respectivamente). Las ratas se sacrificaron y se colectaron muestras representativas del tracto respiratorio que posteriormente se procesaron por la técnica histológica convencional, hasta su inclusión en bloques de parafina. Los cortes histológicos se tiñeron con H-E, tricrómico de Masson y azul de toluidina. En tráquea, bronquiolos y pulmón de las ratas de los grupos I y II se observó una histología normal. En la tráquea de los grupos III, IV y V se identificaron áreas variables de hiperplasia en el epitelio, zonas desprovistas de cilios, signos de aumento en la secreción de las células caliciformes y áreas desprovistas de epitelio que se incrementaron con el tiempo. En la lámina propia se observó congestión vascular e infiltrado mononuclear que incrementó con el tiempo. En los bronquiolos de los grupos III y IV se observó activación de las células de Clara, áreas desprovistas de epitelio, y células mononucleares en la luz bronquiolar. En el grupo V se observaron características histológicas normales. En pulmón de los grupos III y IV se identificó engrosamiento de tabiques alveolares, incremento de las fibras de colágena, congestión y extravasación capilar, además de exudado intralveolar. En el grupo V se observó aparente reversión de algunas alteraciones morfológicas de los grupos previos, aunque otras alteraciones persisten. No se observaron diferencias en el número de las células cebadas.

Petiveria alliacea, is known with different names depending of the place where it is found. Studies with leaves, stem, root or extracts, describe multiple medicinal uses. However, there are few reports that describe toxic effects. This study assessed the morphologic effect induced by steams of the root of P. alliacea on the respiratory tract of Wistar rats. We used 15 rats divided in 5 groups (n= 3): absolute control, 0, 5, 15 and 30 minutes post-exposure (I-V groups, respectively). The rats were sacrificed; representative samples of the respiratory tract were collected, and were processed by conventional histological technique until their inclusion in paraffin blocks. Histological sections were stained with H & E, Masson trichrome and toluidine blue stain. A normal histology was observed in trachea, bronchioles and lungs of rats in groups I and II. In trachea in groups III, IV and V, areas with variable hyperplasia in the epithelium, cells without cilia, increase in the secretion of goblet cells, and areas without epithelium were observed. These morphologic alterations were increased with time. In the lamina propia vascular congestion and mononuclear infiltrate were observed, also increasing with time. In bronchioles in groups III and IV, it was noted activation of Clara cells, areas without epithelium, and mononuclear cells in the bronchiolar light. In group V normal histology was observed. In lung in groups III and IV thickening of interalveolar septa, increase of collagen fibers, capillary congestion, extravasation, and exudates were present. Also was observed an apparent reversion of morphologic alterations of previous groups, but other alterations persist. No difference in mast cells number was observed.

Quick and inexpensive method to elaborate tissue punches useful in paraffin tissue microarrays / Método rápido y económico para la elaboración de dispositivos de punch útiles en microarreglos de tejidos en parafina

The tissue microarrays (TMAs) were first called multitumor block. In 1998 was described the current technique, that uses an innovated sampling method for more than 1,000 cylindrical paraffin tissue core biopsies in a single paraffin block. TMAs are now considered as a useful powerful research tool in Histology and Pathology laboratories, for the standardization of immunohistochemical techniques along with in situ hybridization. However, one disadvantage to its widespread use is the high cost of professional paraffin tissue punches, and the complexity in the development of homemade devices previously described in other studies. This study describes a step by step process to develop four different home-made devices made with materials that are common in hospitals and offices. These devices are useful in Histopathology laboratories to obtain paraffin blocks with until 360 samples of tissue, investing from two to fifteen dollars in the development of each device described.

Los microarreglos de tejido (TMAs) fueron llamados por primera vez como bloque multitumor. En 1998 se describió la técnica actual, que utiliza un novedoso método de muestreo para obtener más de 1,000 cilindros de biopsias de tejidos incluidos en un solo bloque de parafina. Actualmente, los TMAs se consideran una poderosa herramienta de investigación en laboratorios de Histología y Patología, para la estandarización de técnicas inmunohistoquímica e hibridación in situ entre otras. Sin embargo, uno de los inconvenientes para su uso generalizado es el alto costo de los dispositivos profesionales para tejidos en parafina, y la complejidad en la elaboración de los dispositivos caseros descritos previamente en otros estudios. Este estudio describe paso a paso el proceso de elaboración de cuatro dispositivos caseros útiles para la obtención de matrices de tejido elaborados con materiales que son comunes en hospitales y oficinas. Estos dispositivos son útiles en laboratorios de Histopatología con el fin de obtener bloques de parafina de hasta 360 muestras de tejido, con una inversión de 2 a 15 dólares en la elaboración de cada uno de los dispositivos descritos.

El extracto acuoso de orégano (Lippia graveolens HBK) del norte de México tiene actividad antioxidante sin mostrar un efecto tóxico in vitro e in vivo / The aqueous extract from oregano (Lippia graveolens HBK) from the north of Mexico has antioxidant activity without showing a toxic effect in vitro and in vivo

Desde tiempos antiguos la medicina tradicional ha usado extensamente las especies del género Lippia como analgésicos, antiinflamatorios, antipiréticos, antifúngicos, etc. Numerosos estudios describen diversos compuestos presentes en extractos acuosos, metanólicos, o aceites esenciales de estas plantas, siendo los flavonoides los compuestos más abundantes. Sin embargo, la composición y cantidad de los metabolitos secundarios dependen de la zona geográfica, factores climáticos, altitud, época de cosecha y estado de crecimiento de estas plantas. El objetivo de este estudio fue evaluar la actividad antioxidante del extracto acuoso de orégano (Lippia graveolens HBK) del Norte de México y su efecto tóxico in vitro e in vivo. La capacidad antioxidante del extracto acuoso se midió por el método de DPPH en seis diluciones del extracto (5-160 mg/mL) y se utilizó Trolox como referencia; para el efecto tóxico in vitro se usó el ensayo de citotoxicidad con larvas de Artemia salina. Para el efecto in vivo se emplearon 24 ratones árabes machos divididos en 6 grupos de animales (n=4): 4 grupos experimentales con 10, 100, 1000 y 5000 mg del extracto/ kg de peso administrados vía oral respectivamente, además de un grupo control positivo (5 mg de colchicina/kg de peso vía i.p) y un grupo control negativo (solo agua destilada). Después del tratamiento los ratones se sacrificaron y se colectaron muestras de hígado y riñón que se sometieron a estudios histológicos e histoquímicos, además se realizó un análisis cuantitativo. La actividad antioxidante del extracto acuoso de orégano se presentó a 160 mg/mL. La CL50 fue mayor a 1,000 ug/mL por lo que el extracto se considera no tóxico. En el análisis morfológico in vivo con distintas dosis del extracto acuoso de orégano no se observó un efecto tóxico. Los resultados obtenidos validan el uso del orégano en la medicina tradicional...

Since ancient times, traditional medicine has widely used species of the genus Lippia as analgesics, anti-inflammatory, antipyretic, antifungal, etc. Numerous studies describe several compounds present in aqueous extracts, methanol, or essential oils of these plants, being flavonoids the most abundant compounds. However, the composition and quantity of secondary metabolites depend on the geographical area, climatic factors, altitude, time of harvest and growth status of these plants. The objective of this study was to evaluate the antioxidant activity of aqueous extract of oregano (Lippia graveolens HBK) from the North of Mexico and its toxic effect in vitro and in vivo. The antioxidant activity of the aqueous extract was measured by DPPH method in six dilutions of the extract (5-160 mg / mL), Trolox was used as a reference. For the in vitro toxic effect, cytotoxicity assay with larvae of Artemia salina was used. For the in vivo effect, 24 males mice were used and divided into 6 groups (n = 4): 4 experimental groups with 10, 100, 1000 and 5000 mg extract / kg body weight administered orally respectively, also we used a group positive control (5 mg of colchicine / kg body weight administered via ip) and a negative control group (distilled water only). After treatment all mice were sacrificed, and samples from liver and kidney were collected and analyzed by histological and histochemical studies. Also a quantitative analysis was done. The antioxidant activity of aqueous extract of oregano was presented at 160 mg/mL. The LC50 was greater than 1.000 mg/mL, so the extract is considered nontoxic. In the morphological analysis in vivo with different doses of aqueous extract of oregano, no toxic effect was observed. The results validate the use of oregano in traditional medicine...

Comparación Histológica e Inmunohistoquimica de Muestras de Tejido Procesadas por la Técnica Convencional o por el Método Simplificado de Acetonas / Histological and Immunohistochemical Comparison of Tissue Samples Processed by the Conventional Technique or the Acetone Simplified Method

La técnica convencional (TC) que usa alcohol como agente deshidratante, es un método útil en los laboratorios de Histología y Anatomía Patológica. Recientemente, un nuevo método simplificado con acetona (TA) fué diseñado en un intento por reducir el tiempo de procesamiento de los tejidos (de 12 a 4 horas), el costo de reactivos, y como un factor importante para tener un diagnóstico veraz y rápido. En este trabajo se compararon los parámetros histológicos e inmunohistoquímicos en muestras de cáncer de mama, colon y riñón tratadas con ambos métodos. Los cortes fueron teñidos con H & E o tricrómico de Masson. También se llevó a cabo inmunohistoquímica con anticuerpos especificos para la identificación de citoqueratinas AE1/AE3, el receptor de estrógeno y receptor de progesterona. Se realizó un estudio ciego por tres especialistas en morfológía, quienes evaluaron la tinción nuclear, tinción del citoplasma y friabilidad o cambios en la estructura tisular. La especificidad y sensibilidad de la unión de los anticuerpos también fueron evaluadas. Los valores obtenidos para cada parámetro se analizaron estadísticamente con la prueba t de Student. Nuestros resultados muestran que los métodos de TC y TA no modificaron características histológicas como el patrón de tinción, ni se detectaron cambios tisulares. La positividad de la inmunohistoquímica fué similar para ambos métodos. No se observó diferencia estadística entre TC y TA. Nuestros resultados sugieren que la aplicación de la TA no modificó las propiedades histológicas e inmunohistoquímicas y que podría ser un método útil en el análisis morfológico.

The conventional technique (CT) using alcohol as a drying agent, is a useful method of histology and pathology in the laboratory. Recently, a new simplified method with acetone (TA) was designed in an attempt to reduce the processing time of the tissues (12 to 4 hours), the cost of reagents, and as an important factor to have an accurate and prompt diagnosis . This study compared the histological and immunohistochemical parameters in breast cancer, colon and kidney specimens treated with both methods. The sections were stained with H & E or Masson trichrome. Immunohistochemistry study with antibodies specific for the identification of cytokeratin AE1/AE3, the estrogen receptor and progesterone receptor was also carried out. Blind study was conducted by three specialists in morphology, who evaluated the nuclear staining, staining of the cytoplasm and friability or changes in tissue structure. The specificity and sensitivity of antibody binding were also evaluated. The values obtained for each parameter were statistically analyzed with Student t test. Our results show that the methods of CT and TA did not alter histological features as the pattern of staining, and tissue changes were detected. Immunohistochemical positivity was similar for both methods. There was no statistical difference between TC and TA. Our results suggest that implementation of the TA did not alter the histological and immunohistochemical properties and could be a useful method for morphological analysis.