Comparison of percutaneous vs oral infection of hamsters with the hookworm Ancylostoma ceylanicum: Parasite development, pathology and primary immune response.

BACKGROUND: Hundreds of millions of people in poor countries continue to suffer from disease caused by bloodfeeding hookworms. While mice and rats are not reliably permissive hosts for any human hookworm species, adult Golden Syrian hamsters are fully permissive for the human and animal pathogen Ancylostoma ceylanicum. Similar to humans, hamsters may be infected with A. ceylanicum third-stage larvae orally or percutaneously. Oral infection typically leads to consistent worm yields in hamsters but may not accurately reflect the clinical and immunological manifestations of human infection resulting from skin penetration. METHODOLOGY/PRINCIPAL FINDINGS: In this study we compared host responses following percutaneous infection to those utilizing an established oral infection protocol. Infected hamsters exhibited a dose-dependent pathology, with 1000 percutaneous larvae (L3) causing anemia and adult worm recovery comparable to that of 50 orally administered L3. A delayed arrival and maturity of worms in the intestine was observed, as was variation in measured cellular immune responses. A long-term study found that the decline in blood hemoglobin was more gradual and did not reach levels as low, with the nadir of disease coming later in percutaneously infected hamsters. Both groups exhibited moderate growth delay, an effect that was more persistent in the percutaneously infected group. Fecal egg output also peaked later and at lower levels in the percutaneously infected animals. In contrast to orally infected hamsters, antibody titers to larval antigens continued to increase throughout the course of the experiment in the percutaneous group. CONCLUSIONS/SIGNIFICANCE: These results demonstrate that the route of infection with A. ceylanicum impacts disease pathogenesis, as well as humoral and cellular immune responses in an experimental setting. These data further validate the utility of the Golden Syrian hamster as a model of both oral and percutaneous infection with human hookworms.

Survival of the nematophagous fungus Duddingtonia flagrans to in vitro segments of sheep gastrointestinal tract.

The nematophagous fungus Duddingtonia flagrans is used in integrated management of gastrointestinal nematodes in ruminants. The chlamydospores of the fungus, orally administered, pass through the segments of the ruminant digestive tract and, in the feces, capture the nematodes preventing their migration to grasslands. The drastic conditions of the gastrointestinal segments can negatively affect the fungus' biocontrol activity. The aim of this study was to assess the effect of in vitro conditions of the sheep's main gastrointestinal segments on the concentration, viability and nematode predatory ability of D. flagrans chlamydospores. The segments evaluated separately in vitro were the oral cavity, rumen, abomasum, and small intestine. The results showed that chlamydospores concentration was not affected by exposure to the different segments. The viability of the chlamydospores after exposure to the oral cavity (2.53 × 106 CFU/mL) and small intestine (1.24 × 105 CFU/mL) was significantly lower than its control treatment, with values of 6.67 × 106 CFU/mL and 2.31 × 105 CFU/mL respectively. Nematode predatory ability after rumen exposure was reduced by 7% compared to the control treatment, by 25% after abomasum exposure and by 17% after small intestine. This study revealed the individual in vitro effect of each segment of ovine gastrointestinal tract on the integrity of this strain of the fungus D. flagrans affecting its viability and nematode predatory ability under the evaluated conditions. Delivery systems could be designed to protect chlamydospores considering the impact of each gastrointestinal segment.

Cinusa nippon n. sp. (Isopoda: Cymothoidae) Parasitic in the Buccal Cavity of Coastal Puffers (Tetraodontiformes: Tetraodontidae) from Japan, with the First Specimen-Based Record of the Isopod Genus from the Pacific Region.

Cinusa nippon n. sp. is described as the second species of the genus from ovigerous females and adult males found in the buccal cavity of three species of coastal puffers [vermiculated puffer, Takifugu snyderi (Abe, 1989) (type host); panther puffer, Takifugu pardalis (Temminck and Schlegel, 1850); and fine patterned puffer, Takifugu flavipterus Matsuura, 2017], in the southern Sea of Japan off western Honshu, Japan. The female of the new species is distinguished from that of its single congener, Cinusa tetrodontis Schioedte and Meinert, 1884, by the shape of pereonite 1 (straight lateral margins with slightly produced anterolateral angles in the new species vs. rounded anterolateral sides and angles in C. tetrodontis). The number of recurved robust setae on the female's maxilliped article 3 is also different between the two species: C. nippon n. sp. has two robust setae, while C. tetrodontis has three robust setae. Moreover, the male of the new species is differentiated from that of C. tetrodontis in the number of antennal articles and recurved robust setae on the maxilla and maxilliped. Cinusa nippon n. sp. represents the first specimen-based record of the genus from the Pacific region. An amended diagnosis of the genus is provided.

Grub in the mouth: an unusual case with review of literature.

Oral myiasis is a rare disease, identified primarily in non-industrialised nations. It is caused fundamentally by the attack of larvae from Dipteran flies on the human tissues. Predisposing factors for oral myiasis are extraction wounds, destitute oral cleanliness, meagreness, mouth breathing amid rest, suppurative injuries, necrotic tissues, diabetes and perivascular infections primarily within the elderly, extreme halitosis, alcohol addiction, cerebral paralysis and components that favour prolonged mouth opening. Myiasis may have predilection to patients with mental challenges, cerebral palsy and hemiplegia due to unfortunate physical agility. The present case reports an oral myiasis in a 25-year-old woman who was mentally challenged. This condition was treated by topical application of turpentine oil with manual expulsion of hatchlings, taken after by surgical debridement and wide range antimicrobials.

Role of the oral microbiota in cancer evolution and progression.

Bacteria identified in the oral cavity are highly complicated. They include approximately 1000 species with a diverse variety of commensal microbes that play crucial roles in the health status of individuals. Epidemiological studies related to molecular pathology have revealed that there is a close relationship between oral microbiota and tumor occurrence. Oral microbiota has attracted considerable attention for its role in in-situ or distant tumor progression. Anaerobic oral bacteria with potential pathogenic abilities, especially Fusobacterium nucleatum and Porphyromonas gingivalis, are well studied and have close relationships with various types of carcinomas. Some aerobic bacteria such as Parvimonas are also linked to tumorigenesis. Moreover, human papillomavirus, oral fungi, and parasites are closely associated with oropharyngeal carcinoma. Microbial dysbiosis, colonization, and translocation of oral microbiota are necessary for implementation of carcinogenic functions. Various underlying mechanisms of oral microbiota-induced carcinogenesis have been reported including excessive inflammatory reaction, immunosuppression of host, promotion of malignant transformation, antiapoptotic activity, and secretion of carcinogens. In this review, we have systemically described the impact of oral microbial abnormalities on carcinogenesis and the future directions in this field for bringing in new ideas for effective prevention of tumors.

Oral migration of Dirofilaria repens after creeping dermatitis.

We report an autochthonous case of oral dirofilariasis in a 46-year-old female patient exposed in South-Eastern France. The patient first presented eyelid creeping dermatitis of one-week duration, then a sub-mucosal nodule appeared in the cheek. The entire nodule was removed surgically. Histologically, the nodule appeared as inflammatory tissue in which a worm was seen. The molecular analysis, based on cox1 and 12S sequences, identified Dirofilaria repens. Ivermectin treatment was given prior to diagnosis, while taking into consideration the most common causes of creeping dermatitis, but treatment was ineffective. The oral form of dirofilariasis is uncommon and could lead to diagnostic wandering.

TITLE: Migration orale de Dirofilaria repens après une dermatite rampante. ABSTRACT: Nous rapportons un cas autochtone de dirofilariose buccale chez une patiente de 46 ans exposée dans le sud-est de la France. La patiente a d'abord présenté une dermatite rampante des paupières d'une durée d'une semaine, puis un nodule sous-muqueux est apparu dans la joue. Le nodule entier a été retiré chirurgicalement. Histologiquement, le nodule est apparu comme un tissu inflammatoire dans lequel un ver a été observé. L'analyse moléculaire, basée sur des séquences de cox1 et 12S, a identifié Dirofilaria repens. Le traitement à l'ivermectine a été administré avant le diagnostic tout en tenant compte des causes les plus courantes de la dermatite rampante, mais il était inefficace. La forme orale de la dirofilariose est rare et pourrait conduire à une errance diagnostique.

Three-dimensional reconstruction of the feeding apparatus of the tick Ixodes ricinus (Acari: Ixodidae): a new insight into the mechanism of blood-feeding.

The different components of the mouthparts of hard ticks (Ixodidae) enable these parasites to penetrate host skin, secrete saliva, embed, and suck blood. Moreover, the tick's mouthparts represent a key route for saliva-assisted pathogen transmission as well as pathogen acquisition from blood meal during the tick feeding process. Much has been learned about the basic anatomy of the tick's mouthparts and in the broad outlines of how they function in previous studies. However, the precise mechanics of these functions are little understood. Here, we propose for the first time an animated model of the orchestration of the tick mouthparts and associated structures during blood meal acquisition and salivation. These two actions are known to alternate during tick engorgement. Specifically, our attention has been paid to the mechanism underlining the blood meal uptake into the pharynx through the mouth  and how ticks prevent mixing the uptaken blood with secreted saliva. We animated function of muscles attached to the salivarium and their possible opening /closing of the salivarium, with a plausible explanation of the movement of saliva within the salivarium and massive outpouring of saliva.

Hooked on you: shape of attachment structures in cymothoid isopods reflects parasitic strategy.

BACKGROUND: Parasite attachment structures are critical traits that influence effective host exploitation and survival. Morphology of attachment structures can reinforce host specificity and niche specialisation, or even enable host switching. Therefore, it is important to understand the determinants of variation in attachment structures. Cymothoid isopods are striking ectoparasites of fishes that include the infamous 'tongue-biters.' They are known to parasitise hosts in one of four qualitatively distinct anatomical regions. Here, we quantify variation in cymothoid attachment structures - hook-like appendages called dactyli - and test whether differences in dactylus shape are correlated with parasite mode (where they attach), allometry, or both, using multivariate ordinary least squares regression. We also assess the influence of shared ancestry on shape using a molecular phylogeny to weight our models using phylogenetic generalised least squares regression. RESULTS: We find clear differences in shape between externally-attaching and internally-attaching cymothoids but also between anterior and posterior dactyli across various species with the same attachment mode. Allometric effects are significant for anterior but not posterior dactyli. Mouth-attaching species show greater shape variability than gill- and mouth-attaching species. We find no evidence that there are clade-specific patterns of association between parasite mode and dactylus shape. CONCLUSIONS: Parasite mode appears to be the main driver of attachment morphology. This likely reflects several components of parasite ecology including feeding and functional demands of attachment in different microhabitats. Geometric morphometric approaches to the quantification of shape variation of simple structures is an effective tool that provides new insights into the evolvability of parasite attachment.

First record of infestation by nasal leeches, Limnatis nilotica (Hirudinida, Praobdellidae), from cattle in Italy.

In July 2017, twenty cattle of a free-grazing herd were found to be infested with leeches in the mouth. Main signs were bloody sialorrhea and/or a purple-red colour of the lower lip. Leeches, in a variable number (1 to 3) per animal, were found at the lingual frenulum or on the sublingual vestibular mucosa and were morphologically identified as Limnatis nilotica. To the best of our knowledge, this is the first report of cattle infestation by L. nilotica in Italy. Besides recalling the attention to leech infestation and suggesting its inclusion in the differential diagnosis of animals with suggestive signs, this short report also provides practitioners with easy-going morphological keys for proper diagnosis and discrimination among species.

Leech (Myzobdella lugubris) infestations in largemouth bass (Micropterus salmoides) in Back Bay, Virginia, USA.

Back Bay is an oligohaline, coastal bay in southeast Virginia, USA. Since 2004, leeches have been observed in the oral cavities of largemouth bass (Micropterus salmoides) in this body of water. Leeches (Myzobdella lugubris) have previously been documented in the oral cavities of largemouth bass in the Currituck Sound, which is confluent with Back Bay on its southern border. Supplemental stocking of largemouth bass in Back Bay since 2009 has resulted in an increasing population; however, concern exists that leech infestation may be negatively affecting health of larger fish, which are still less abundant than expected. Despite the wide distribution of this leech, there is little available literature regarding its health impacts on hosts. In this study, we examine potential impacts of oral leech infestations on stress markers and haematological parameters of largemouth bass in Back Bay. No significant changes in plasma glucose or cortisol were observed between leech-infested and uninfested fish, and haematological parameters were not significantly different between the groups. Further, there was no evidence of systemic infections associated with leech infestation.

Molecular identification of Trichomonas tenax in the oral environment of domesticated animals in Poland - potential effects of host diversity for human health.

INTRODUCTION: The protozoan Trichomonas tenax is considered to be a human specific flagellate of the oral cavity, found in humans with poor oral hygiene and advanced periodontal disease. Morphological variability and great similarity between species occurring in humans and animals, complicate the specific identification of trichomonads, using microscopic examination and other standard parasitological techniques. OBJECTIVE: The aim of the study was to search for and identify T. tenax in domesticated animals using molecular methods. The obtained data were assessed in terms of potential effects of a spread of the species deriving from the animals in the human environment. MATERIAL AND METHODS: 301 animals: 142 dogs, 57 cats and 102 horses, were examined in terms of their mouth status and occurrence of trichomonads. ITS1-5.8S rRNA-ITS2 region was amplified and sequenced. RESULTS: Finally, 7 dogs, 3 cats and 1 horse were diagnosed positive for T. tenax by PCR. In the oral cavity of 9 /11 animals, gingivitis and dental plaque accumulation were diagnosed. 9 /11 sequences of trichomonad isolates showed 100% identity with T. tenax sequence derived from the GenBank. The sequences of 2 isolates differed by substitutions. CONCLUSIONS: It was proved that T. tenax, considered so far as a human specific parasite, can also inhabit the oral cavity of dog, cat and horse. To summarize, T. tenax was detected in the mouths of different domesticated animals, indicating that in Poland it can colonize a wider range of hosts than previously known. The owners of 3 dogs showed oral tissue inflammation of different intensity and were also positive for T. tenax; therefore, oral trichomonosis spread from humans to domestic animals and conversely should be taken into consideration.

The discovery of Lepeophtheirus acutus Heegaard, 1943 (Copepoda: Caligidae) from two new elasmobranch hosts in the Mediterranean Sea, and a comparative redescription of Lepeophtheirus rhinobati Luque, Chaves et Cezar, 1998.

In this study, supplementary information on the morphology of the siphonostomatoid copepod Lepeophtheirus acutus Heller, 1865 is given based on new material collected from the ventral body surface and mouth cavity of common guitarfish, Rhinobatos rhinobatos (Linnaeus) and from the branchial cavity of bull ray, Aetomylaeus bovinus (Geoffroy Saint-Hilaire) caught in Iskenderun Bay, Turkey. This is the first report of L. acutus from Mediterranean waters. Key diagnostic characters of both sexes are reported, supported by light and scanning electron microscopy observations. In addition, Lepeophtheirus rhinobati Luque, Chaves et Cezar, 1998, which is closely related to L. acutus and has been reported from the same host genus, Rhinobatos, is reexamined based on paratypes stored in the collections of the United States National Museum of Natural History. Some of the key diagnostic characters which were incompletely known or lacking in the original description of both sexes of L. rhinobati are redescribed and/or presented for the first time.

Prevalence of two Entamoeba gingivalis ST1 and ST2-kamaktli subtypes in the human oral cavity under various conditions.

Advances in molecular biology have facilitated analyses of the oral microbiome; however, the parasites role is poorly understood. Periodontal disease is a multifactorial process involving complex interactions among microorganisms, the host, and environmental factors. At present, the precise composition of the mouth parasites microbiota is unclear. Two protozoan species have been detected in the oral microbiota: Trichomonas tenax and Entamoeba gingivalis, and a new variant, E. gingivalis-ST2-kamaktli, was recently identified by us. In this study, both E. gingivalis and the new E. gingivalis-ST2-kamaktli variant were detected in the oral cavities of people with healthy periodontium, individuals undergoing orthodontic treatment, and patients with periodontal disease. In the group with healthy periodontium, the prevalence of E. gingivalis-ST1 was 48.6% and that of E. gingivalis-ST2-kamaktli 29.5%, with a combined prevalence of 54.3%. In patients undergoing orthodontics treatment, 81.2% carried both amoebas, with 47.5% having E. gingivalis-ST1 and 73.8% E. gingivalis-ST2-kamaktli. In people with periodontal disease, the prevalence of E. gingivalis-ST1 was 57.8%, and that of E. gingivalis-ST2-kamaktli 50.0%, with a combined prevalence of 73.5%; hence, E. gingivalis-ST1 and E gingivalis-ST2-kamaktli were detected in all three groups. The question arises, what are E. gingivalis-ST1 and E. gingivalis-ST2-kamaktli doing in the oral cavity? Although, the answer remains unclear, our results suggest that each amoeba subtype is genetically distinct, and they exhibit different patterns of infectious behavior. We hypothesize that E. gingivalis-ST1 and E. gingivalis-ST2-kamaktli may represent separate species. Our data contribute to better understanding of the roles of E. gingivalis-ST1 and E. gingivalis-ST2-kamaktli in the oral microbiota.

Expression of matrix metalloproteinase-2 and metalloproteinase-9 in the skin of dogs with visceral leishmaniasis.

The skin is the first organ to be infected by the parasite in canine visceral leishmaniasis. The enzyme matrix metalloproteinase (MMP) acts towards degradation of the extracellular matrix (ECM) and modulation of the inflammatory response against many kinds of injuries. The aims of this study were to evaluate the expression of MMP-2 and MMP-9 through immunohistochemistry and zymography on the skin (muzzle, ears, and abdomen) of dogs that were naturally infected by Leishmania spp. and to compare these results with immunodetection of the parasite and with alterations to the dermal ECM. Picrosirius red staining was used to differentiate collagen types I and III in three regions of the skin. The parasite load, intensity of inflammation, and production of MMP-2 (latent) and MMP-9 (active and latent) were higher in the ear and muzzle regions. MMP-9 (active) predominated in the infected group of dogs and its production was significantly different to that of the control group. Macrophages, lymphocytes, and plasma cells predominated in the dermal inflammation and formed granulomas in association with degradation of mature collagen (type I) and with discrete deposition of young collagen (type III). This dermal change was more pronounced in dogs with high parasite load in the skin. Therefore, it was concluded that the greater parasite load and intensity of inflammation in the skin led consequently to increased degradation of mature collagen, caused by increased production of MMPs, particularly active MMP-9, in dogs with visceral leishmaniasis. This host response profile possibly favors systemic dissemination of the parasite.

A new subtype of Entamoeba gingivalis: "E. gingivalis ST2, kamaktli variant".

Entamoeba gingivalis is a protozoan that resides in the oral cavity. Using molecular biology techniques, we identified a novel organism that shares the same ecological niche as E. gingivalis. To differentiate this organism from E. gingivalis, we named it "kamaktli variant." By sequencing the 18S-ITS1-5.8S-ITS2 rRNA region, we demonstrated that kamaktli variant is 89% identical to E. gingivalis. To elucidate the relationship between kamaktli variant and E. gingivalis, we performed a phylogenetic analysis. Both taxa clustered in the same clade with high support, indicating that the amoebas are closely related (98/99/1.00, maximum parsimony/maximum likelihood/MrBayes, respectively). Given this information, we propose that these molecular differences between kamaktli variant and E. gingivalis ST1 are sufficient to distinguish them as independent subtypes, and we name the new subtype "E. gingivalis ST2, kamaktli variant."

Portación de Candida spp. en cavidad oral en diabéticos y no diabéticos / Carrying of Candida spp. in the oral cavity in diabetic and non-diabetic patients

Introducción: Candida spp. es un habitante normal de la microbiota humana, que puede originar infecciones superficiales y sistémicas de carácter oportunista. En pacientes diabéticos se incrementa el riesgo de infecciones por esta levadura, lo cual estaría determinado por la portación de Candida spp. Esta portación es variable, así se observa en cavidad oral desde 13,7 al 64 por ciento. Objetivo: establecer los porcentajes de colonización y posibles factores asociados en este grupo de alto riesgo. Método: se realizó un estudio descriptivo en un total de 172 pacientes diabéticos y no diabéticos. Las muestras de enjuague bucal se sembraron en agar Sabouraud y CHROMagar Candida. Los aislamientos se sometieron a pruebas fenotípicas y a reacción en cadena de la polimerasa múltiple para su identificación. Las variables demográficas, los hábitos de higiene oral, el uso de prótesis dental, así como los niveles de hemoglobina glucosilada se evaluaron para determinación de frecuencias y asociación por chi2 y análisis multivariado, mediante el programa SPSS versión 19.0. Resultados: el porcentaje de colonización en el total de la población diabética y no diabética (n= 172) fue de 33,7 por ciento. La distribución por especies fue de Candida albicans (63,8 por ciento), Candida glabrata (10,3 por ciento), Candida tropicalis (6,9 por ciento), Candida krusei (5,2 por ciento), Candida dubliniensis (3,4 por ciento), Candida parapsilosis (3,4 por ciento), Candida lusitaniae (1,7 por ciento), Candida guilliermondii (1,7 por ciento) y Candida spp. (no identificada, 3,4 por ciento). En sujetos no diabéticos el porcentaje de colonización fue de 27,9 por ciento y en diabéticos de 36,9 por ciento. En los sujetos del estudio se encontró que 14,9 por ciento tenía control glúcemico por los niveles de hemoglobina glucosilada, el 57,6 por ciento utilizaba prótesis dentales y el 63,9 por ciento practicaba higiene oral regular. Conclusión: Candida albicans es la especie predominante en ambos grupos, con un porcentaje significativo de las especies no albicans en estos pacientes. El uso de prótesis dental es un factor coadyuvante para la colonización por especies del género Candida(AU)

Introduction: Candida spp. is a normal inhabitant of the human microbiota, which can cause superficial and systemic infections of an opportunistic nature. In diabetic patients the risk of infections by this yeast increases, which would be determined by the carrying of Candida spp. This carrying is variable, as observed in the oral cavity from 13.7 to 64 percent. Objective: to establish the percentages of colonization and possible associated factors in this high-risk group. Method: a descriptive study was carried out in a total of 172 diabetic and non-diabetic patients. Mouthwash samples were seeded on Sabouraud agar and CHROMagar Candida. The isolates were subjected to phenotypic tests and to a multiple polymerase´s chain reaction for identification. Demographic variables, oral hygiene habits, the use of dental prostheses, as well as glycosylated hemoglobin levels were evaluated for frequency and association determination by chi2 and multivariate analysis, using the SPSS program version 19.0. Results: the percentage of colonization in the total of the diabetic and non-diabetic population (n= 172) was 33.7 percent. The distribution by species was Candida albicans (63.8 percent), Candida glabrata (10.3 percent), Candida tropicalis (6.9 percent), Candida krusei (5.2 percent), Candida dubliniensis (3.4 percent), Candida parapsilosis (3.4 percent), Candida lusitaniae (1.7 percent), Candida guilliermondii (1.7 percent), and Candida spp. (unidentified, 3.4 percent). In non-diabetic patients the percentage of colonization was 27.9 percent and in diabetics 36.9 percent. In the study´s patients, it was found that 14.9 percent had glycemic control by glycosylated hemoglobin levels, 57.6 percent used dental prostheses, and 63.9 percent practiced regular oral hygiene. Conclusion: Candida albicans was the predominant specie in both groups, with a significant percentage of the non-albicans species in these patients. The use of dental prostheses was a contributory factor for colonization by species of the genus Candida(AU)

Portación de Candida spp. en cavidad oral en diabéticos y no diabéticos / Carrying of Candida spp. in the oral cavity in diabetic and non-diabetic patients

Introducción: Candida spp. es un habitante normal de la microbiota humana, que puede originar infecciones superficiales y sistémicas de carácter oportunista. En pacientes diabéticos se incrementa el riesgo de infecciones por esta levadura, lo cual estaría determinado por la portación de Candida spp. Esta portación es variable, así se observa en cavidad oral desde 13,7 al 64 por ciento. Objetivo: establecer los porcentajes de colonización y posibles factores asociados en este grupo de alto riesgo. Método: se realizó un estudio descriptivo en un total de 172 pacientes diabéticos y no diabéticos. Las muestras de enjuague bucal se sembraron en agar Sabouraud y CHROMagar Candida. Los aislamientos se sometieron a pruebas fenotípicas y a reacción en cadena de la polimerasa múltiple para su identificación. Las variables demográficas, los hábitos de higiene oral, el uso de prótesis dental, así como los niveles de hemoglobina glucosilada se evaluaron para determinación de frecuencias y asociación por chi2 y análisis multivariado, mediante el programa SPSS versión 19.0. Resultados: el porcentaje de colonización en el total de la población diabética y no diabética (n= 172) fue de 33,7 por ciento. La distribución por especies fue de Candida albicans (63,8 por ciento), Candida glabrata (10,3 por ciento), Candida tropicalis (6,9 por ciento), Candida krusei (5,2 por ciento), Candida dubliniensis (3,4 por ciento), Candida parapsilosis (3,4 por ciento), Candida lusitaniae (1,7 por ciento), Candida guilliermondii (1,7 por ciento) y Candida spp. (no identificada, 3,4 por ciento). En sujetos no diabéticos el porcentaje de colonización fue de 27,9 por ciento y en diabéticos de 36,9 por ciento. En los sujetos del estudio se encontró que 14,9 por ciento tenía control glúcemico por los niveles de hemoglobina glucosilada, el 57,6 por ciento utilizaba prótesis dentales y el 63,9 por ciento practicaba higiene oral regular. Conclusión: Candida albicans es la especie predominante en ambos grupos, con un porcentaje significativo de las especies no albicans en estos pacientes. El uso de prótesis dental es un factor coadyuvante para la colonización por especies del género Candida(AU)

Introduction: Candida spp. is a normal inhabitant of the human microbiota, which can cause superficial and systemic infections of an opportunistic nature. In diabetic patients the risk of infections by this yeast increases, which would be determined by the carrying of Candida spp. This carrying is variable, as observed in the oral cavity from 13.7 to 64 percent. Objective: to establish the percentages of colonization and possible associated factors in this high-risk group. Method: a descriptive study was carried out in a total of 172 diabetic and non-diabetic patients. Mouthwash samples were seeded on Sabouraud agar and CHROMagar Candida. The isolates were subjected to phenotypic tests and to a multiple polymerase´s chain reaction for identification. Demographic variables, oral hygiene habits, the use of dental prostheses, as well as glycosylated hemoglobin levels were evaluated for frequency and association determination by chi2 and multivariate analysis, using the SPSS program version 19.0. Results: the percentage of colonization in the total of the diabetic and non-diabetic population (n= 172) was 33.7 percent. The distribution by species was Candida albicans (63.8 percent), Candida glabrata (10.3 percent), Candida tropicalis (6.9 percent), Candida krusei (5.2 percent), Candida dubliniensis (3.4 percent), Candida parapsilosis (3.4 percent), Candida lusitaniae (1.7 percent), Candida guilliermondii (1.7 percent), and Candida spp. (unidentified, 3.4 percent). In non-diabetic patients the percentage of colonization was 27.9 percent and in diabetics 36.9 percent. In the study´s patients, it was found that 14.9 percent had glycemic control by glycosylated hemoglobin levels, 57.6 percent used dental prostheses, and 63.9 percent practiced regular oral hygiene. Conclusion: Candida albicans was the predominant specie in both groups, with a significant percentage of the non-albicans species in these patients. The use of dental prostheses was a contributory factor for colonization by species of the genus Candida(AU)

Molecular characterization of Acanthamoeba strains isolated from the oral cavity of hemodialysis patients in Iran.

Free-living amoebae (FLA) of the genus Acanthamoeba are opportunistic pathogenic agents able to cause life-threatening infections in immunosuppressed patients. Chronic kidney disease impairs adaptive and innate immunity. Thus, patients with chronic kidney disease are prone to opportunistic infections by potentially pathogenic FLA. Therefore, in the present study, the investigation of Acanthamoeba genotypes isolated from the oral cavity of hemodialysis patients of reference hospitals in Iran was aimed, using both morphology and molecular (sequence-based analysis) tools. Furthermore, classification of the strains at the genotype level was performed on the basis of differences in the diagnostic fraction 3 (DF3) region of the 18S rRNA gene. The pathogenic potential of the isolated amoebae was also determined using thermotolerance and osmotolerance assays. Out of the 187 oral cavity samples investigated, nine (4.8%) were positive for FLA. DNA sequencing of the ASA.A1 region of the 18S rRNA gene revealed that the isolated strains belonged to the Acanthamoeba T1 and T4 genotypes. Genotype T1 was isolated for the first time from a patient in Iran. Interestingly, the T1 strain (AN2 strain) exhibits a high pathogenic potential in tolerance assays. The pathogenicity assay revealed that five strains were able to grow at high temperatures (37-40 °C) and high osmolarity (0.5 and 1 M D-mannitol) conditions; thus, they were considered as potentially pathogenic strains. Moreover, two of the patients were positive for Vermamoeba genus. The present study is the first report of genotype T1 isolation in Iran and the first to identify the occurrence of Acanthamoeba and Vermamoeba genera in patients undergoing hemodialysis worldwide. Monitoring hemodialysis and renal failure patients should be a priority for possible control of Acanthamoeba and other FLA-related diseases.

Unraveling Chagas disease transmission through the oral route: Gateways to Trypanosoma cruzi infection and target tissues.

Oral transmission of Trypanosoma cruzi, the causative agent of Chagas disease, is the most important route of infection in Brazilian Amazon and Venezuela. Other South American countries have also reported outbreaks associated with food consumption. A recent study showed the importance of parasite contact with oral cavity to induce a highly severe acute disease in mice. However, it remains uncertain the primary site of parasite entry and multiplication due to an oral infection. Here, we evaluated the presence of T. cruzi Dm28c luciferase (Dm28c-luc) parasites in orally infected mice, by bioluminescence and quantitative real-time PCR. In vivo bioluminescent images indicated the nasomaxillary region as the site of parasite invasion in the host, becoming consistently infected throughout the acute phase. At later moments, 7 and 21 days post-infection (dpi), luminescent signal is denser in the thorax, abdomen and genital region, because of parasite dissemination in different tissues. Ex vivo analysis demonstrated that the nasomaxillary region, heart, mandibular lymph nodes, liver, spleen, brain, epididymal fat associated to male sex organs, salivary glands, cheek muscle, mesenteric fat and lymph nodes, stomach, esophagus, small and large intestine are target tissues at latter moments of infection. In the same line, amastigote nests of Dm28c GFP T. cruzi were detected in the nasal cavity of 6 dpi mice. Parasite quantification by real-time qPCR at 7 and 21 dpi showed predominant T. cruzi detection and expansion in mouse nasal cavity. Moreover, T. cruzi DNA was also observed in the mandibular lymph nodes, pituitary gland, heart, liver, small intestine and spleen at 7 dpi, and further, disseminated to other tissues, such as the brain, stomach, esophagus and large intestine at 21 dpi. Our results clearly demonstrated that oral cavity and adjacent compartments is the main target region in oral T. cruzi infection leading to parasite multiplication at the nasal cavity.