Cyto and genotoxicity of gold nanoparticles in human hepatocellular carcinoma and peripheral blood mononuclear cells

Engineered nanomaterials have been extensively applied as active materials for technological applications. Since the impact of these nanomaterials on health and environment remains undefined, research on their possible toxic effects has attracted considerable attention. It is known that in humans, for example, the primary site of gold nanoparticles (AuNps) accumulation is the liver. The latter has motivated research regarding the use of AuNps for cancer therapy, since specific organs can be target upon appropriate functionalization of specific nanoparticles. In this study, we investigate the geno and cytotoxicity of two types of AuNps against human hepatocellular carcinoma cells (HepG2) and peripheral blood mononuclear cells (PBMC) from healthy human volunteers. The cells were incubated in the presence of different concentrations of AuNps capped with either sodium citrate or polyamidoamine dendrimers (PAMAM). Our results suggest that both types of AuNps interact with HepG2 cells and PBMC and may exhibit in vitro geno and cytotoxicity even at very low concentrations. In addition, the PBMC were less sensitive to DNA damage toxicity effects than cancer HepG2 cells upon exposure to AuNps.     

Rolandic encephalopathy and epilepsia partialis continua following bone marrow transplant

Epilepsia partialis continua (EPC) is a condition defined by prolonged focal myoclonus. Often resistant to therapy, EPC in children is frequently present in Rasmussen encephalitis, a form of chronic encephalitis of uncertain etiology. We discuss a child who developed bilateral EPC 5 months after a bone marrow transplant. Neuroimaging studies showed signal abnormalities on both sensory-motor areas. An extensive search failed to reveal the etiology of the disorder, but treatment with a broad-spectrum anti-viral agent was associated with resolution of the process. An unidentified infectious agent may be responsible for an encephalitis of the motor strip in immunosuppressed patients.     

Quality management: its use in nursing

The Quality Management has been used and it is a reality in the hospitals. Thus the authors comment about its importance for Nursing and analyse its utilization in a Nursing Service of a private hospital, with purpose to evaluate the implementation form, nurses' involvement and the Deming' Principles application. Data show that the implementation has brought good results, nurses are engaged in the process and the Deming's Principles have been utilized, adequate or inadequately.     

Expression of nitric oxide synthases and in vitro migration of eosinophils from allergic rhinitis subjects

The expression of nitric oxide (NO) synthases and the role of the NO cyclic GMP pathway on the migration of eosinophils from untreated patients with allergic rhinitis were investigated. Inducible NO synthase was strongly expressed in eosinophils from healthy individuals, but not in eosinophils from allergic rhinitis patients. The neuronal isoform was observed in eosinophils from each group studied, whereas no staining for the endothelial isoform was detected in either group. The chemotaxis to N-formyl-methionyl-leucyl-phenylalanine (fMLP, 5 x 10(-7) M) and eotaxin (100 ng/ml) was significantly potentiated in allergic rhinitis eosinophils. In both groups, N(omega)-nitro-L-arginine methyl ester (L-NAME, 1.0 mM) or 1H(1,2,4)-oxadiazolo(4,3,-a)quinoxalin-1-one (ODQ, 0.2 mM) markedly reduced the chemotaxis. The selective iNOS inhibitor N-(3-(aminomethyl)benzyl)acetamidine (1400 W, 0.1-1.0 mM) significantly reduced the chemotaxis of eosinophils from healthy but not from allergic rhinitis subjects. The inhibition by L-NAME was restored by 3-morpholinosydnonimine (SIN-1) and S-nitroso-N-acetyl-penicillamine, whereas the inhibition by ODQ was restored by dibutyryl cyclic GMP. In conclusion, both endothelial and inducible NO synthase isoforms are absent in allergic rhinitis eosinophils, suggesting that the NO cyclic GMP pathway in this cell type is maintained through the activity of a neuronal isoform.     

Models for neuro-oncological preclinical studies: solid orthotopic and heterotopic grafts of human gliomas into nude mice

To study the optimum therapeutic modalities for treating human malignant brain tumors in vivo without ethical limitations, a model of heterotopic and another of orthotopic xenografting into nude mice were developed. For the first implantation, 11 human high-grade gliomas and 4 low-grade tumors were microsurgically grafted on epigastric vessels. The 11 high-grade gliomas, but no low-grade tumors, were established into nude mice. Afterwards, all these mouse-adapted gliomas which grafted into other nude mice developed. Introduction of a microcatheter into the femoral artery or vein permitted infusion for magnetic resonance imaging (MRI) and treatment. A bladder catheter setting and electrode implantation allowed urine sampling and ECG or EEG recording. Thus, the most important parameters of chemo- and radiotherapy to destroy a maximum number of malignant cells or to inhibit their divisions and the hosts reactions to treatment can be studied. The human gliomas transplanted onto the mouse brain infiltrated the host brain at great distances from the tumor, as in human patients. So, this second implantation constitutes a representative model of the evolution of human gliomas, and allows the study of malignant cell migration in the brain before, during and after treatment determined with the heterotopic model and to appreciate the tolerance of the colonized brain to these treatments. Echography and MRI allowed us to follow the macroscopic evolution with or without treatment of the malignant brain tumors transplanted onto mouse brains. It should now be possible to undertake the same clinical studies on patients after appropriate consideration of ethical and scientific constraints.     

Cerebral trypanosomiasis and AIDS

A 36 year-old black female, complaining of headache of one month's duration presented with nausea, vomiting, somnolence, short memory problems, loss of weight, and no fever history. Smoker, intravenous drugs abuser, promiscuous lifestyle. Physical examination: left homonimous hemianopsia, left hemiparesis, no papilledema, diffuse hyperreflexia, slowness of movements. Brain CT scan: tumor-like lesion in the splenium of the corpus calosum, measuring 3.5 x 1.4 cm, with heterogeneous enhancing pattern, suggesting a primary CNS tumor. Due to the possibility of CNS infection, a lumbar puncture disclosed an opening pressure of 380 mmH(2)0; 11 white cells (lymphocytes); glucose 18 mg/dl (serum glucose 73 mg/dl); proteins 139 mg/dl; presence of Trypanosoma parasites. Serum Elisa-HIV tests turned out to be positive. Treatment with benznidazole dramatically improved clinical and radiographic picture, but the patient died 6 weeks later because of respiratory failure. T. cruzi infection of the CNS is a rare disease, but we have an increasing number of cases in HIV immunocompromised patients. Diagnosis by direct observation of CSF is uncommon, and most of the cases are diagnosed by pathological examination. It is a highly lethal disease, even when properly diagnosed and treated. This article intends to include cerebral trypanosomiasis in the differential diagnosis of intracranial space-occupying lesions, especially in immunocompromised patients from endemic regions.     

Diagnostic use of 3 techniques for identification of microsporidian spores among AIDS patients in Portugal

The calcofluor stain (CF), the monoclonal antibody (MAb) 3B6 indirect immunofluorescence assay (IFA) and the modified trichrome blue stain (MT) were compared in terms of their reproducibility in a routine laboratory and in order to evaluate the percentage of cases of microsporidiosis in Portuguese HIV patients. A total of 166 faeces samples, 71 pulmonary specimens and 43 urine samples were studied using the 3 techniques. CF had a high sensitivity and a moderate specificity when applied to faeces samples. The sensitivity was lower with pulmonary specimens. The method is easy and quick to perform but readings take a long time to obtain. The MAb 3B6 IFA had a good to excellent sensitivity when applied to faeces and urine samples, but moderate sensitivity in pulmonary specimens. Readings were quick and easy to obtain, but the assay took longer to perform than the other 2 techniques. There was a greater correlation between the results obtained with the MT and MAb 3B6 IFA techniques than between those obtained with the MT and CF techniques. In conclusion, the MT performed better than the MAb 3B6 IFA and CF and continues to have an important place in a routine laboratory for the diagnosis of microsporidiosis. This work also confirms the existence of a relatively high proportion (30%) of cases of infection with Microsporidia, especially intestinal microsporidiosis, in HIV patients in Portugal.