Selective isolation of agents of chromoblastomycosis from insect-associated environmental sources.

Chromoblastomycosis is a neglected disease characterized by cutaneous, subcutaneous or disseminated lesions. It is considered an occupational infectious disease that affects mostly rural workers exposed to contaminated soil and vegetal matter. Lesions mostly arise after a traumatic inoculation of herpotrichiellaceous fungi from the Chaetothyriales order. However, the environmental niche of the agents of the disease remains obscure. Its association with insects has been predicted in a few studies. Therefore, the present work aimed to analyze if social insects, specifically ants, bees, and termites, provide a suitable habitat for the fungi concerned. The mineral oil flotation method was used to isolate the microorganisms. Nine isolates were recovered and phylogenetic analysis identified two strains as potential agents of chromoblastomycosis, i.e., Fonsecaea pedrosoi CMRP 3076, obtained from a termite nest (n = 1) and Rhinocladiella similis CMRP 3079 from an ant exoskeleton (n = 1). In addition, we also identified Fonsecaea brasiliensis CMRP 3445 from termites (n = 1), Exophiala xenobiotica CMRP 3077 from ant exoskeleton (n = 1), Cyphellophoraceae CMRP 3103 from bees (n = 1), Cladosporium sp. CMRP 3119 from bees (n = 1), Hawksworthiomyces sp. CMRP 3102 from termites (n = 1), and Cryptendoxyla sp. from termites (n = 2). The environmental isolate of F. pedrosoi CMRP 3076 was tested in two animal models, Tenebrio molitor and Wistar rat, for its pathogenic potential with fungal retention in T. molitor tissue. In the Wistar rat, the cells resembling muriform cells were observed 30 d after inoculation.

Análise histológica do estômago da prole de ratas Wistar submetidas ao consumo crônico de álcool durante a prenhez / Histological analysis of stomach of offspring of Wistar rats submitted to chronic alcohol consumption during pregnancy

O consumo de bebidas alcoólicas na gravidez consiste em um importante problema de saúde pública, visto que, pode causar prejuízos na organogênese de diversos órgãos, incluindo o estômago, entretanto, poucos estudos avaliam o efeito da exposição pré-natal ao álcool nesse órgão. O objetivo deste estudo foi analisar histologicamente o estômago da prole de ratas submetidas ao consumo crônico de álcool durante a prenhez. Utilizou-se 10 ratas prenhes divididas nos grupos: Controle - ratas que receberam água destilada durante todo período gestacional e Álcool ­ ratas que receberam álcool etílico absoluto (3g/kg/dia) durante todo período gestacional. Logo após o nascimento, 12 neonatos (6 machos e 6 fêmeas) de cada grupo foram anestesiados e os estômagos coletados. Posteriormente, os órgãos foram fixados e processados seguindo a técnica histológica de rotina. Foram feitas análises histomorfométricas das camadas mucosa, muscular e da parede total do estômago. Observou-se que as proles macho e fêmea expostas ao etanol apresentaram diminuição da área de epitélio, contudo, os machos também mostraram redução significativa do número de células epiteliais. Demonstrou-se ainda redução na espessura das camadas mucosa, muscular e da parede total do estômago da prole fêmea do grupo Álcool. No entanto, a camada muscular apresentou aumento significativo em sua espessura no grupo de neonatos machos expostos ao etanol. Assim, concluímos que a exposição pré-natal ao álcool provoca efeitos nocivos sobre o estômago dos neonatos, contudo, estudos futuros são necessários para melhor elucidar os mecanismos envolvidos na patogênese e possíveis consequências para os animais na fase adulta.

Consumption of alcoholic beverages during pregnancy is a significant public health issue since it can damage the organogenesis of several organs, including the stomach; however, few studies evaluate the effect of prenatal exposure to alcohol in this organ. The objective of this study was to analyze the histology of the stomach of offspring of rats submitted to chronic alcohol consumption during pregnancy. Ten pregnant rats were divided into two groups: Control - rats receiving distilled water throughout the gestation period, and Alcohol - rats receiving absolute ethyl alcohol (3g/kg/day) throughout the gestation period. After birth, 12 newborn rats (6 males and 6 females) from each group were anesthetized and their stomachs were collected. Subsequently, the organs were fixed and processed following the routine histological technique. The mucosa, muscle and total stomach were submitted to histomorphometric analyses. It was observed that the male and female offspring exposed to ethanol had a decrease in the epithelium area. However, males also showed a significant reduction in the number of epithelial cells. There was also a reduction in the layer's thickness mucosa, muscle and total stomach wall of the female offspring from the alcohol group. Additionally, the muscular layer presented a significant increase in its thickness in the group of male neonates exposed to ethanol. It can be concluded that prenatal exposure to alcohol causes harmful effects on neonates' stomachs; however, future studies are necessary to better elucidate the mechanisms involved in the pathogenesis and possible consequences for the animals in adulthood.

Characterization of Functional, Safety, and Probiotic Properties of Enterococcus faecalis AG5 Isolated From Wistar Rat, Demonstrating Adherence to HCT 116 Cells and Gastrointestinal Survivability.

Gut microbiota remains a prominent source for a diverse range of potential probiotics. In this context, the current study explored the rectal region of experimental Wistar rat for the isolation of potent probiotic. Sixteen lactic acid bacteria (LAB), from rectal swab of Wistar rats, were subjected to evaluation of probiotic properties. Among all, AG5 was found unique with consistent probiotic properties and was further identified as Enterococcus faecalis AG5 (NCBI accession number KT248537) using 16S rDNA sequencing, followed by BLAST analysis. Since the Enterococci strains inhibit various food-borne pathogens efficiently while proving itself as a safe probiotic candidate, the study further evaluated the safety of the strain AG5 using primer specific PCR amplification which revealed the existence of gene encoding gelE, asa1, efaA, ace, vanA, and vanB and negative for cylA, hyl, and esp respectively. SEM analysis confirmed the adherence ability of AG5 to HCT 116 cells. Adherence was found to be non-colonial and scattered manner. Furthermore, the strain demonstrated a significant survivability during simulated gastrointestinal transit. Taken together, the E. faecalis AG5 was found potential probiotic candidate with future implication in both food and health industry.

Screening of Lactobacillus strains for their ability to produce conjugated linoleic acid in milk and to adhere to the intestinal tract.

Conjugated linoleic acid (CLA) has been shown to provide beneficial effects on health; however, the amount consumed in food is far from that required for the desired effects. Thus, increasing the CLA content in dairy foods through milk fermentation with specific lactic acid bacteria (LAB) offers an interesting alternative. Moreover, some LAB may be able to adhere to the intestinal mucosa and produce CLA through endogenous synthesis. Therefore, the objective of this study was to screen LAB isolates for their ability to produce CLA in skim milk and in simulated gastrointestinal conditions. Additionally, the ability of selected CLA-producing LAB to adhere to the intestinal mucosa in a murine model was assessed. Results showed that of 13 strains of Lactobacillus tested, only 4 were able to produce CLA in skim milk supplemented with linoleic acid (13.44 ± 0.78 to 50.9 ± 0.26 µg/mL). Furthermore, these 4 Lactobacillus strains were able to survive and produce CLA in simulated gastrointestinal conditions and to adhere to the intestinal mucosa of Wistar rats after 7 d of oral inoculation with fluorescently labeled bacteria. Accordingly, these 4 Lactobacillus strains may be used to manufacture fermented dairy foods to increase CLA content, and consumption of these fermented milks may result in CLA produced endogenously by these LAB.

Prueba oral de carga de lípidos en ratas Wistars como procedimiento fiable para el estudio de la mala absorción de triglicéridos / Oral lipid loading test in Wistar rats as a reliable method for the study of the triacylglycerol malabsorption

La mayor parte de la digestión de lípidos se lleva a cabo por la lipasa pancreática, siempre en la parte superior del lumen intestinal por secreciones del jugo pancreático. En este artículo, se describe un nuevo método rápido y menos estresante para evaluar la actividad de la lipasa pancreática que se puede realizar por un solo operador. Con el fin de hacerlo, el plasma sanguíneo se analizó para caracterizar la cinética de absorción gastrointestinal lipídica con diferentes tensoactivos fisiológicos y con el inhibidor de la lipasa pancreática Orlistat como control positivo. El resultado mostró que fue posible evaluar cinco animales en menos de 30 minutos con un operador y que el tratamiento con Orlistat consiguió prevenir la absorción sistémica de los TAG hasta 120 minutos después del tratamiento. A la luz de estos resultados se concluye que el método descrito en este estudio podría ser empleado para investigar el proceso de digestión de lípidos en diferentes condiciones(AU)

Most of the lipid digestion is carried out by pancreatic lipase, secreted in the upper part of the intestinal lumen by pancreatic juice secretions. In this paper, we describe a new single stressless and fast method to evaluate plasma triacylglycerol levels on Wistar rats under anaesthesia and with minimal personal training. After the administration of different diet treatments, plasma triacylglycerol (TAG) levels were analyzed at 30, 60, 120, 180 minutes to characterize the lipidic gastrointestinal absorption. Orlistat, a known antiobesity drug, was used as positive control. The results shown that the method was able to differentiate the treatments administered utilizing up to five animals at each time step. In addition, with this method was shown that Orlistat treatment prevents TAG systemic uptake at 30 and 60 minutes compared to a control diet without it. On the light of these results we conclude that the method described in this study could be employed to evaluate short-term lipid digestion(AU)

Efectos de la ingestión de una dieta con alto contenido en grasas en ratas Wistar crónicamente infectadas con Trypanosoma cruzi / The effects of ingesting a high-fat diet on Wistar rats chronically infected with Trypanosoma cruzi

Se investigan los efectos de la ingestión de una dieta con alto contenido en grasas en ratas albinas (R. norvegicus) crónicamente infectadas con Trypanosoma cruzi “Planalto”, mediante pruebas de diagnóstico sero-parasitológicas, cuantificación del Índice de Masa Corporal (IMC), detección de la Proteína C Reactiva (PCR), evaluación de los niveles de lípidos plasmáticos (colesterol total, lipoproteínas de alta densidad - HDL y triglicéridos) y presencia de depósitos lipídicos en la arteria aorta. Durante el curso de la infección chagásica, se detectaron parasitemias patentes entre los 10 y 35 días pi, con un máximo promedio de 36,68±2 trips./mm³ de sangre a los 25 días. A los 90 días pi, se evidenció ausencia de parasitemias y presencia de anticuerpos IgG anti- T. cruzi. Las ratas chagásicas (A) y las sanas (C) sometidas a la dieta rica en grasas, mostraron: diferencias significativas (p<0,05) en el IMC, en comparación con los grupos de ratas sometidas a la dieta normal (B: infectadas y D: sanas); discreta reacción de la PCR en los sueros de las ratas infectadas B; aumento significativo en los niveles de colesterol total, colesterol - HDL y triglicéridos en los grupos A y C en comparación con los grupos controles B y D (p<0,05). El estudio histológico de las arterias de ratas del grupo A, reveló importantes depósitos lipídicos ubicados en la capa muscular próximos a las capas íntima y adventicia. Estos resultados sugieren que el incremento en los niveles de lípidos plasmáticos estimulado por el proceso infeccioso, son los principales mecanismos por el cual T. cruzi podría estar influyendo en la iniciación o progresión de placas ateromatosas

The effects of ingesting a high fat diet on albino rats (R. norvegicus) chronically infected with Trypanosome cruzi “Planalto” were researched using serological and parasitological diagnostic tests, body mass index (BMI) quantification, detection of C-Protein Reactive (CPR), evaluation of the plasmatic lipid levels (total cholesterol, high density lipoproteins HDL and triglycerides) and the presence of lipidic deposits in the aorta artery. During the course of the chagasic infection, patent parasitemias were detected between the ages of 10 and 35 days post-infection (pi) with a maximum average of 36.68 ± 2 tryps/mm³ of blood at 25 days. At 90 days pi, the absence of parasitemias and the presence of IgG anti T. cruzi antibodies were in evidence. The chagasic rats in chronic phase (A) and the healthy controls (C) submitted to a high fat diet showed: 1. Significant variations (p0.05) in the BMI, in comparison with the rat groups receiving a normal diet (B: infected and D: healthy rats); 2. A discrete CRP reaction in the serum of infected rats B; 3. A significant increase was shown in the total cholesterol levels, HDL cholesterol and triglycerides for groups A and C in comparison with control groups B and D (p0.05). The histological study of rat arteries in group A revealed important lipid deposits located in the muscular layer near the intimal and adventitial layer. These results suggest that the increase in plasmatic lipid levels stimulated by the infectious process are the main mechanisms through which T. cruzi could be influencing the initiation or the progression of atheromatous plaque

Normal microbiota of the perialveolar region of incisors of rats / Microbiota normal da região perialveolar de incisivos em ratos

Identificou-se a microbiota normal da região peri-alveolar de incisivos em 72 ratos Wistar, com 70-90 dias de idade e 280-330g de peso. As bactérias foram coletadas com suabes embebidos em solução salina. Do material depositado em tubo contendo 460µl de Brain Heart Infusion e diluído em 1:10, retirou-se 1µl para semeadura em placas de Petri. O crescimento médio foi 1,4x10(6) ± 2,6x10(5)UFC/ml. Segundo a ordem das freqüências, as bactérias encontradas foram: Bacillus sp., Staphylococcus aureus, Streptococcus viridans, Corynebacterium sp., Staphylococcus coagulase negativa, Enterococcus sp., Staphylococcus saprophyticcus, Escherichia coli, Klebsiella oxytoca, Klebsiella pneumoniae e Serratia liquefaciens. De todas as bactérias isoladas, as Gram-positivas e as Gram-negativas compreenderam 91,2 por cento e 8,8 por cento, respectivamente. Dentre as Gram-positivas, a mais freqüente foi Bacillus sp.(31,2 por cento) e a menos, Staphylococcus saprophyticcus (3,0 por cento). Quanto às bactérias Gram-negativas, a mais encontrada foi Escherichia coli (50,1 por cento) e a menos, Serratia liquefaciens (6,2 por cento)

Coinfection of laboratory rats with Mycoplasma pulmonis and Chlamydia pneumoniae.

Routine examinations of conventional outbred Wistar rats in our laboratory showed increased serum levels of alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, and urea. Electron microscopy and specific reactions showed C. pneumoniae and M. pulmonis in lung, liver, spleen, heart, and kidney sections. We could not exclude the fact that other infectious microorganisms detected through routine health surveillance affected the Wistar rat colony; however, we have not identified any of those microorganisms by electron microscopy of the organs listed. Natural coinfection of C. pneumoniae and M. pulmonis can occur in laboratory rats and is associated with histopathological and functional compromise of many organs. Further studies comparing different conventional animals and specific pathogen-free animals are necessary to better understand the present findings and to define whether coinfection influences the results of experimental studies with rats.

Experimental evidence of host specificity of Bartonella infection in rodents.

A large number of Bartonella species and genetic variants were compared for their ability to cause bacteremia in different rodent species: the cotton rat (Sigmodon hispidus), white-footed mouse (Peromyscus leucopus), BALB/c mouse and Wistar rat. Experimental data supported field observations that host specificity can occur among certain Bartonella species and rodent species. Bacteremia could only be readily produced in cotton rats or white-footed mice if the strains used for inoculation were originally obtained from the same species or from a phylogenetically close species. A few Bartonella colonies could be observed in the blood of some BALB/c mice by 7 days after inoculation, but no evidence of the persistence of the infection was found. Host specificity suggests the possibility of a long co-speciation of Bartonella species with their rodent hosts. Host-parasite relationships measured by the duration and level of bacteremia and the minimal infectious dose may serve as additional criteria for classification of Bartonella isolates obtained from natural environments.

Genetic heterogeneity of Pneumocystis carinii from rats of several regions and strains.

Pneumocystis carinii is a major opportunistic pathogen which has been found in the lungs of a wide variety of mammalian host species, and the fact suggests the possibility of intraspecific variation. Until now, P. carinii from different mammalian species are differentiated as subspecies, and the rats are known to be infected by two subspecies. The present study investigated genetic heterogeneity of P. carinii isolates from two strains of rats in Korea and China by molecular karyotyping, RFLP and sequencing analysis. Karyotypes of P. carinii were grouped into three, two from two strains of rats in Korea and one from rats in China. However RFLP of PCR product of ribosomal and MSG gene of the P. carinii isolates showed same pattern. The sequence homology rates of alpha-tubulin DNA of the P. carinii isolates were 96% in Seoul Wistar rats, 93% in Seoul Sprague-Dawley rats, and 85% in Chinese Sprague-Dawley rats. The present finding confirmed that P. carinii from rats in Korea are grouped into two karyotype strains which are different from that of P. carinii from rats in China. The Chinese isolate shows a little different sequences of alpha-tubulin DNA.

High resolution scanning electron microscopy study of the bacteria adhesion in the epithelial cell membranes of the third anterior part of young rat tongue mucosa

Los autores relatan la presencia de bacterias sobre la superficie de las células epiteliales el tercio anterior de la mucosa lingual de ratas jóvenes a través del microscopio de barrido de alta resolución. Las células epiteliales de las papilas filiformes y fungiformes revelaron numerosos grupos de bacterias. Estas bacterias están fijadas sobre la membrana de las células epiteliales claramente visualizadas en imágenes tridimensionales

Enterotoxigenicidad de campylobacter jejuni subsp. jejuni y su relación con aumento de AMPc y alteración electrolítica en el intestino de ratas / The relationship of campylobacter jejuni subsp. jejuni enterotoxigenicity and the increase of cAMP and electrolytic alterations in the rat intestine

Background: Small intestine alterations produced by the enterotoxigenic capacity of Campylobacter jejuni subsp. jejuni are similar to the hydric, electrolytic and pathological changes caused by choleraic and thermolabile Escherichia coli toxins. Aim: To study the enterotoxigenic capacity of 4 strains of Campylobacter jejuni subsp. jejuni using the intestinal loop model. Material and methods: Rat intestinal loops were inoculated with culture filtrates of the four strains. Enterotoxigenicity was assessed by fluid accumulation, the increase in Na+ and Cl- in the loop fluid, and cAMP increases in loop tissues. An enterotoxigenic Escherichia coil strain and sterile Brucella both were used as positive and negative controls, respectively. Results: The filtrates of two strains produced fluid accumulation in the loops, significantly increased Na+ and Cl - secretion to the intestinal lumen and increased tissue cAMP levels. Conclusions: Some strains of Campylobacter jejuni subsp. jejuni are able to show enterotoxigenicity in vivo, increasing cAMP levels in the intestinal cells and altering electrolyte exchange mechanisms

Natural uterine Mycoplasma pulmonis infection in female rats.

Uterine washings from 124 apparently healthy and non-pregnant female Wistar rats of different ages were cultured for mycoplasmas and bacteria. The animals originated from four conventional breeding colonies which were known to be chronically infected with M. pulmonis from the previous microbiological examination. Mycoplasmas were isolated from the uterus in 30.6% of examined females. All the isolates were biochemically and seriologically identified as M. pulmonis. Uterine colonization with this organism was first evidenced in non-mated female rats at the age of three months. After mating the number of infected females rapidly increased. This observation points out the microbiologically uncontrolled mating as an important factor in the distribution of genital infection within the colony. Bacterial examination of uterine washings revealed only ubiquitous organisms in some animals. Gross lesions in the form of purulent salpingitis and mild endometritis were observed only in two animals.

Effect of time of exposure to rat coronavirus and Mycoplasma pulmonis on respiratory tract lesions in the Wistar rat.

The effects of time of exposure on the progression of pulmonary lesions in rats inoculated with Mycoplasma pulmonis and the rat coronavirus, sialodacryoadenitis virus (SDAV) were studied, using six groups of 18 SPF Wistar rats (n = 108). Rats were inoculated intranasally as follows: Group 1, sterile medium only; Group 2, sterile medium followed one week later by 150 TCID50 SDAV; Group 3, sterile medium followed by 10(5.7) colony forming units of M. pulmonis; Group 4, SDAV followed one week later by M. pulmonis; Group 5, M. pulmonis followed one week later by SDAV; Group 6, M. pulmonis followed two weeks later by SDAV. Six rats from each group were euthanized at one, two and three weeks after the final inoculation. In a separate experiment, six additional animals were inoculated in each of groups 3, 5 and 6 (n = 18) and were sampled at five weeks after they had received M. pulmonis. Bronchoalveolar lavage and quantitative lung mycoplasma cultures were conducted on two-thirds of the rats. Histopathological examination and scoring of lesion severity were performed on all animals. Based on the prevalence and extent of histopathological lesions, bronchoalveolar lavage cell numbers, neutrophil differential cell counts and the isolation of M. pulmonis, the most severe disease occurred in the groups that received both agents. There was no significant difference in lesion severity between the groups receiving both agents other than in those examined during the acute stages of SDAV infection. Based on these results, it is evident that SDAV enhances lower respiratory tract disease in Wistar rats whether exposure occurs at one week prior to or at various intervals following M. pulmonis infections.

Effect of systemic monosodium L-glutamate on muscarinic cholinergic receptors in selected rat brain regions during development

[3H]quinuclidinyl benzilate ([3H]QNB) binding to muscarine acetylcholine receptors (mAchR) was measured in cerebral cortex and caudate nucleus of rats ata the ages of 7, 14, and 21 days, which had received a subconvulsive intraperitoneal dose of monosodium L-glutamate (MSG) (4 mg/g) on postnatal days 1, 3, 5 and 7. MSG treatment determined an increasse of mAchR density in cerebral cortex. This was 8, 15 and 25 per cent at day 7, 14 and 21, respectively. In cuadate nucleus, a significant increase of mAchR density was detected at day 7 (240 per cent). However, on postnatal day 14, mAchR binding in caudate nucleus of MSG-Treated rats was only 47 per cent higher, while at 21 days, no changes in mAchR binding were found. When MSG was injected to adults rats, no changes in brain mAchR density were detected. Data suggest that early administration of MSG affects the development of mAchR in cerebral cortex and caudate nucleus, whereas the adult brain cortical cholinergic transmission is not sensitive to parenterally administered MSG