Leonora Maciel de Souza Vianna

Antitumor effect and toxicity of free rhodium (II) citrate and rhodium (II) citrate-loaded maghemite nanoparticles in mice bearing breast cancer

BackgroundMagnetic fluids containing superparamagnetic iron oxide nanoparticles represent an attractive platform as nanocarriers in chemotherapy. Recently, we developed a formulation of maghemite nanoparticles coated with rhodium (II) citrate, which resulted in in vitro cytotoxicity enhanced up to 4.6 times when compared to free rhodium (II) citrate formulation on breast carcinoma cells. In this work, we evaluate the antitumor activity and toxicity induced by these formulations in Balb/c mice bearing orthotopic 4T1 breast carcinoma.MethodsMice were evaluated with regard to the treatments’ toxicity through analyses of hemogram, serum levels of alanine aminotransferase, iron, and creatinine; DNA fragmentation and cell cycle of bone marrow cells; and liver, kidney and lung histology. In addition, the antitumor activity of rhodium (II) citrate and maghemite nanoparticles coated with rhodium (II) citrate was verified by tumor volume reduction, histology and immunohistochemistry.ResultsRegarding the treatments’ toxicity, no experimental groups had alterations in levels of serum ALT or creatinine, and this suggestion was corroborated by the histopathologic examination of liver and kidney of mice. Moreover, DNA fragmentation frequency of bone marrow cells was lower than 15% in all experimental groups. On the other hand, the complexes rhodium (II) citrate-functionalized maghemite and free rhodium (II) citrate led to a marked growth inhibition of tumor and decrease in CD31 and Ki-67 staining.ConclusionsIn summary, we demonstrated that both rhodium (II) citrate and maghemite nanoparticles coated with rhodium (II) citrate formulations exhibited antitumor effects against 4T1 metastatic breast cancer cell line following intratumoral administration. This antitumor effect was followed by inhibition of both cell proliferation and microvascularization and by tumor tissue injury characterized as necrosis and fibrosis. Remarkably, this is the first published report demonstrating the therapeutic efficacy of maghemite nanoparticles coated with rhodium (II) citrate. This treatment prolonged the survival period of treated mice without inducing apparent systemic toxicity, which strengthens its use for future breast cancer therapeutic applications.

Lobomycosis: diagnosis and management of relapsed and multifocal lesions

We report a case of lobomycosis in the left leg of a patient that had traveled to the endemic Brazilian Amazon region. After surgical resection of the lesion, there was relapse with local dissemination of the disease and the treatment was successfully performed by oral itraconazole and cryosurgery.

Case report of subcutaneous entomophthoromycosis with retroperitoneal invasion

The authors describe a case of entomophthoromycosis in a previously healthy patient, who presented with an abscess in the right buttock. After surgical drainage it evolved into a retroperitoneal tumor. The patient improved clinically after resection of the mass and ketoconazole treatment. The histopathological analysis showed the Splendore-Hoeppli phenomenon, suggesting Basidiobolus ranarum infection, a zygomycosis generally restricted to the subcutaneous tissue, with rare gastrointestinal involvement.

Adiaspiromicose pulmonar: achado casual em paciente falecido de febre amarela

During an outbreak of yellow fever (rural form of the infection) ocurred recently in the State of Goias, Brazil, a patient, with clinical manifestations suggestive of the infection, died in the University Hospital of Brasilia, DF, on the fifth day from admission. Postmortem examination revealed, microscopically, the characteristic alterations of the infection, and discovered in the lungs and hilar lymph nodes round microrganisms identified as adiaconidia of Emmonsia parva var. crescens.

Oropharynx HPV status and its relation to HIV infection

Background The number of oropharyngeal lesions caused by HPV (Human papillomavirus) has been increasing worldwide in the past years. In spite of the clinical relevance of HPV infection in the anogenital tract of HIV-positive patients, the relevance of oropharynx HPV infection in these patients is not clear. The aim of the present study was to detect HPV infection, and clinical and cytological changes in the oropharynx of HIV-positive patients. Methods Samples collected from the oropharynx of 100 HIV-positive patients were subjected to hybrid capture (HC), conventional and liquid-based cytology. Clinical data were also collected to investigate the relation with HPV status. Results High and low-risk types of HPV were present in 8% and 16.7% of the total sample. The mean ± sd (maximum-minimum) of the relative ratio light unit (RLU)/cutoff (CO) was 2.94 ± 2.58 (1.09–7.87) and 1.61 ± 0.65 (1.07–2.8) for high- and low-risk-HPV, respectively. By cytology, dysplasia was not detected, but atypical squamous cells of undetermined significance (ASC-US) were diagnosed in two samples. No clinical change, suggestive of dysplasia/cancer, was detected. Conclusion Our study was able to detect and characterize HPV infection by hybrid capture, which may represent a good tool for screening and follow-up of HPV in the studied population. The frequency and viral load of HPV were low. Neither clinical nor cytological changes suggestive of dysplasia/neoplasia were observed in oropharynx of HIV-positive patients.

Electrical stimulation structurally affects the tissues of the rectum and anus of nulliparous rats

Considering that the muscles of the anus perform a critical role in maintaining continence, losses in their structure can negatively affect the physiological control of the intestinal contents. Anorectal electro‐stimulation (ARES) has been reported to have a positive effect on the functionality of treated patients, but how ARES affects the structural tissues of the anorectal segment remains unknown. Because the study of how ARES structurally affects human tissues is not possible, this study aimed to clarify these effects in a murine model, which has a similar anorectal segment (structure and physiology) to humans. For the descriptive and comparative study, randomly selected nulliparous adult Wistar rats (n = 5) were submitted to 30 anorectal sessions of ARES with a biphasic current (700 μs, 50 Hz from 2 to 4 mA). After treatment, the animals were euthanized, and the anorectal segments were dissected and processed for histopathological analysis. Our results showed that ARES increased the widths of the mucosal, submucosal and muscle layers of the rectum, as well as the number of leukocytes in the mucosa. ARES also caused hyperplasia of the smooth muscle of the internal anal sphincter and hypertrophy of the external anal sphincter muscle. In conclusion, our results showed that ARES had not only a positive effect on the structure (morphology) of all tissues associated with the rectum and anus but, more importantly, on the structural gain of the muscles (hyperplasia and hypertrophy), which could point to a functional gain of the anal sphincter, reinforcing the applicability of ARES as a non‐invasive treatment for anal incontinence.

HIPPOCAMPAL AND CEREBELLAR HISTOLOGICAL CHANGES AND THEIR BEHAVIOURAL REPERCUSSIONS CAUSED BY BRAIN ISCHAEMIC HYPOXIA EXPERIMENTALLY INDUCED BY SODIUM NITRITE

Introduction: Brain ischaemic hypoxia can produce severe neurological damage that leads to behavioural disorders. This research analysed the hippocampal and cerebellar histological alterations caused by brain ischaemic hypoxia experimentally induced by sodium nitrite (NaNO2) and possible direct repercussions of this hypoxia on behaviour. Methodology: An experimental study was carried out by administering 60 mg/kg NaNO2 to 10 Wistar rats at 3 months of age for 15 consecutive days. Ten control rats did not receive NaNO2. To assess behavioural repercussions, the animals were evaluated in Open Field, Elevated Plus‐Maze (EPM), and Forced Swim tests before and after injury to evaluate locomotion, anxiety, and depression, respectively. Markers of stress were evaluated by measuring the blood levels of cortisol, glucose, cholesterol, and lactate. The presence of hippocampal lesions was verified by histologically studying the CA1–CA4 areas. Sections of the cerebellum were also evaluated because Purkinje cells are highly sensitive to ischaemic hypoxia and may serve as markers for this process. Results: The number of neurons with lesions was significantly higher in animals exposed to NaNO2 in the hippocampus areas CA2, CA3, and CA4. The cerebellum was also very vulnerable to hypoxia, presenting extensive lesion áreas. These results are correlated with the parameters of the anxiety and depression tests. Conclusion: NaNO2 promoted brain damage due to ischaemic hypoxia in rats. Intoxicated animals showed decreased brain weights; damage in hippocampus and cerebellum; and anxiogenic and depressive behaviour. Graphical abstract Figure. No caption available.

Cytological diagnosis of paracoccidioidomycosis: A report of four cases

Paracoccidioidomycosis (PCM) is a common deep mycosis in South America caused by Paracoccidioides brasiliensis, a dimorphic fungus. Biopsy is the most frequent diagnostic method. The aim of this article is reporting four cases of PCM, in which intraoral involvement simulated squamous‐cell carcinoma and was diagnosed by exfoliative cytology. We highlight this diagnostic tool as a simple, low cost, painless, noninvasive, and fast diagnostic method for PCM. Diagn. Cytopathol. 2013;41:374–376.