The pathogenic potential of Blastocystis sp. in experimental models
requires further investigation. In this work, the pathogenicity of this parasite in
the gastrointestinal tract of male Swiss mice was evaluated according to the inoculum
size and period of infection. Animals were infected intragastrically, with 100, 500,
1,000, 5,000 and 10,000 Blastocystis sp. vacuolar forms obtained
from a mixture of eight human isolates cultured axenically in Jones' medium. After
seven, 14, 21, 28 and 60 days of infection, the animals were sacrificed and fragments
of the small intestine (duodenum), large intestine, and cecum were subjected to
histopathological analysis. Blastocystis sp. triggered an
inflammatory response in the different tissues analyzed, with a predominance of
mononuclear cells. The parasite was found in the muscular layer of the cecum, showing
its invasive character. Larger inocula triggered inflammatory processes earlier
(seven days) than smaller ones (from 21 days). We conclude that, in the proposed
model, the pathogenicity of Blastocystis sp. isolates that were
studied is related to inoculum size and period of infection.
Introduction: Cases of bacterial resistance in urinary tract infections (UTIs) have increased significantly, mainly due to indiscriminate use of antimicrobials. Objective: To evaluate the prevalence and antimicrobial susceptibility of microorganisms isolated in urine cultures of patients of Consórcio Intermunicipal de Saúde da Comunidade dos Municípios da Região de Campo Mourão (CIS-COMCAM) clinical laboratory. Method: We performed a retrospective study of data from urine culture and sensitivity done between January 2012 and December 2013. Results: The most prevalent bacteria were Escherichia coli; women were the most affected gender and people 16-45 years, the most affected age group. The sensitivity profile showed that the antimicrobial combination trimethoprim/ sulfamethoxazole was not associated with the highest rate of bacterial resistance (59.7%) and the combination of amoxicillin/clavulanic acid showed the lowest resistance rate (15.3%). For most antimicrobials, including ciprofloxacin and norfloxacin, the rates of bacterial resistance have increased from 2012 to 2013 with statistical significance (p < 0.05) in some cases. Discussion: The prevalence of Gram-negative bacilli in urinary infections is due to the fact that intestinal flora is rich in enterobacteria, and women are most affected by anatomical factors. The development of bacterial resistance to antimicrobials probably arises from their indiscriminate use. Conclusion: The rate of microbial resistance has risen, showing the need for a more effective control of antimicrobial use.
Infection of Giardia duodenalis is one of the most common human parasitic disease worldwide. This infection may be related to important changes in the enteric nervous system. The objective of this study was to evaluate the myenteric and submucosal plexuses, the intestinal muscle layer, and gastrointestinal transit in mice infected with assemblages A and B of G. duodenalis. Swiss albino mice (Mus musculus) were infected with assemblages A and B of G. duodenalis for 15 days. Gastrointestinal transit time was evaluated before euthanasia. Duodenum and jejunum were removed for histological and immunohistochemical analyses. It was observed a reduction in the enteric glial cell count and a decrease in the ratio of enteric glial cells to neurons. The number of neurons did not change, but morphological changes were observed in the duodenum and jejunum in both plexuses, including an increase in the nuclear area and a reduction of cell bodies in the myenteric plexus and a decrease in the nuclear area in the submucosal plexus. A reduction of the thickness of the muscle layer was observed in the duodenum, with no significant differences in the gastrointestinal transit times. Assemblages A and B of G. duodenalis decrease the number of enteric glial cells in the myenteric and submucosal plexuses, decrease the thickness of the muscle layer, and change the morphology of neurons. Graphical abstract ᅟ.
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