Cutaneous basal cell carcinoma with endobronchial metastasis

Although basal cell carcinoma is a very common malignancy, metastasis from this tumour is extremely rare. For this reason, many plastic surgeons, dermatologists and physicians dealing with skin malignancies consider this as a locally invasive malignancy. We present a rare case of metastatic basal cell carcinoma manifested as a bronchial tumour. This case highlights the fact that despite basal cell carcinoma’s local invasive potential, the possibility of distant metastasis still exists and clinicians should therefore be cautious about interpreting extracutaneous symptoms. Chest physicians should always consider the possibility of this rare tumour in the lungs in patients with a history of large basal cell carcinomas in the head and neck region.     

Stimulation of retrotrapezoid nucleus Phox2b‐expressing neurons rescues breathing dysfunction in an experimental Parkinson’s disease rat model

Emerging evidence from multiple studies indicates that Parkinson’s disease (PD) patients suffer from a spectrum of autonomic and respiratory motor deficiencies in addition to the classical motor symptoms attributed to substantia nigra degeneration of dopaminergic neurons. Animal models of PD show a decrease in the resting respiratory rate as well as a decrease in the number of Phox2b‐expressing retrotrapezoid nucleus (RTN) neurons. The aim of this study was to determine the extent to which substantia nigra pars compact (SNc) degeneration induced RTN biomolecular changes and to identify the extent to which RTN pharmacological or optogenetic stimulations rescue respiratory function following PD‐induction. SNc degeneration was achieved in adult male Wistar rats by bilateral striatal 6‐hydroxydopamine injection. For proteomic analysis, laser capture microdissection and pressure catapulting were used to isolate the RTN for subsequent comparative proteomic analysis and Ingenuity Pathway Analysis (IPA). The respiratory parameters were evaluated by whole‐body plethysmography and electromyographic analysis of respiratory muscles. The results confirmed reduction in the number of dopaminergic neurons of SNc and respiratory rate in the PD‐animals. Our proteomic data suggested extensive RTN remodeling, and that pharmacological or optogenetic stimulations of the diseased RTN neurons promoted rescued the respiratory deficiency. Our data indicate that despite neuroanatomical and biomolecular RTN pathologies, that RTN‐directed interventions can rescue respiratory control dysfunction.     

Micromorphology of the Dental Pulp Is Highly Preserved in Cancer Patients Who Underwent Head and Neck Radiotherapy

Introduction

Teeth are often included in the radiation field during head and neck radiotherapy, and recent clinical evidence suggests that dental pulp is negatively affected by the direct effects of radiation, leading to impaired sensitivity of the dental pulp. Therefore, this study aimed to investigate the direct effects of radiation on the microvasculature, innervation, and extracellular matrix of the dental pulp of patients who have undergone head and neck radiotherapy.

Methods

Twenty-three samples of dental pulp from patients who finished head and neck radiotherapy were analyzed. Samples were histologically processed and stained with hematoxylin-eosin for morphologic evaluation of the microvasculature, innervation, and extracellular matrix. Subsequently, immunohistochemical analysis of proteins related to vascularization (CD34 and smooth muscle actin), innervation (S-100, NCAM/CD56, and neurofilament), and extracellular matrix (vimentin) of the dental pulp was performed.

Results

The morphologic study identified preservation of the microvasculature, nerve bundles, and components of the extracellular matrix in all studied samples. The immunohistochemical analysis confirmed the morphologic findings and showed a normal pattern of expression for the studied proteins in all samples.

Conclusions

Direct effects of radiotherapy are not able to generate morphologic changes in the microvasculature, innervation, and extracellular matrix components of the dental pulp in head and neck cancer patients.     

The role of IL‐6 on apical periodontitis: a systematic review

The aim of this review was to examine current knowledge of the role of interleukin‐6 (IL‐6) in apical periodontitis (AP) pathogenesis as an inflammatory or pro‐inflammatory cytokine. It also looked at whether IL‐6 could serve as a measure for differential diagnosis or as a biomarker that can further predict the progression of bone resorption. A systematic review relating to AP and IL‐6 was made via PubMed, BIOSIS, Cochrane, EMBASE and Web of Science databases using keywords and controlled vocabulary. Two independent reviewers first screened titles and abstracts and then the full texts. The reference lists of the identified publications were examined for additional titles. Eighteen papers were studied in total. In vitro studies (n = 6) revealed that IL‐6 is present in AP, and its levels are proportional to the size of the periapical lesions. Neutrophils and macrophages resident in these lesions can produce IL‐6 in vitro after a bacterial stimulus. Animal studies (n = 5) showed that IL‐6 is present in AP and that osteoblasts can produce IL‐6 in vivo. On the other hand, two studies using IL‐6 knockout mice revealed larger periapical lesions when compared with control groups, demonstrating IL‐6's role as an anti‐inflammatory cytokine. In human studies (n = 7), IL‐6 was identified in AP, and its levels were higher in symptomatic, epithelialized and large lesions than in asymptomatic and small lesions. These data lead to the conclusion that IL‐6 may play a pro‐inflammatory role, increasing its levels and reabsorbing bone in the presence of infections. When IL‐6 is not present, other cytokines such as IL‐1 and TNF‐α induce bone resorption. Further studies about the relationship between AP development and the cytokine network must be performed to establish the exact role of each cytokine in the inflammatory process.     

Molecular docking to Toxoplasma gondii thymidylate synthase-dihydrofolate reductase and efficacy of raltitrexed in infected mice

Parasitology Research - Toxoplasmosis is a zoonosis of worldwide distribution. Currently, two drugs, pyrimethamine and sulfadiazine, are used as a reference in the treatment of toxoplasmosis, but...     

Microstructural characterization and fracture behavior of a microhybrid and a nanofill composite

OBJECTIVES: To characterize the microstructure and composition of two different composites, and to determine their influence on the physical properties and fracture behavior. METHODS: The microstructure and composition of a microhybrid (Filtek Z250-Z2) and a nanofill (Filtek Supreme-SU) composite were analyzed using scanning electron microscopy (SEM) and electron dispersive spectroscopy (EDS). Filler wt% was determined by thermogravimetric analysis. Hardness (H) and degree of conversion (DC) were evaluated at top and bottom surfaces of 2-mm thick specimens, and the dynamic elastic modulus (E) was determined with ultrasonic waves. Bar specimens (n=30) were subjected to flexure loading and flexural strength (sigmaf) was calculated (MPa). Fractographic analysis (FA) was performed to determine the fracture origin (c) for calculation of fracture toughness (KIc), and these results were compared to those from the single edge notch beam (SENB) method. Results were statistically analyzed using two-way ANOVA, Student's t-test and Weibull analysis (alpha=0.05). RESULTS: Z2 had higher filler wt%, H, E and DC at 2-mm depth as compared with SU. The fracture behavior (sigmaf and KIc) and the structural reliability (m) of the composites were similar. Results of KIc tested by SENB or calculated from fracture surfaces from flexure testing were similar. SIGNIFICANCE: The microstructural organization of the composites determines their physical properties, in spite of the similar filler content. In contrast, the microstructure did not influence the fracture behavior and the structural reliability of these highly filled composites. FA was shown to be a reliable method for determining the KIc of composites.     

Modulation of drug resistance in staphylococcus aureus by a kaempferol glycoside from herissantia tiubae (malvaceae)

In an ongoing project to evaluate natural compounds isolated from plants from the Brazilian biodiversity as modulators of antibiotic resistance, kaempferol‐3‐O‐β‐d‐(6″‐E‐p‐coumaroyl) glucopyranoside (tiliroside), isolated from Herissantia tiubae (Malvaceae) was investigated using the strain SA‐1199B of Staphylococcus aureus, which overexpresses the norA gene encoding the NorA efflux protein which extrudes hydrophilic fluorquinolones and some biocides, such as benzalkonium chloride, cetrimide, acriflavine and ethidium bromide. The minimum inhibitory concentrations (MICs) of the antibiotics and biocides were determined by the microdilution assay in the absence and in the presence of sub‐inhibitory concentration of tiliroside. Although tiliroside did not display relevant antibacterial activity (MIC = 256 µg/mL), it modulated the activity of antibiotics, i.e. in combination with antibiotics a reduction in the MIC was observed for norfloxacin (16‐fold), ciprofloxacin (16‐fold), lomefloxacin (four‐fold) and ofloxacin (two‐fold), and an impressive reduction in the MICs for the biocides (up to 128‐fold). The results presented here represent the first report of a kaempferol glycoside as a putative efflux pump inhibitor in bacteria. The present finding indicates that H. tiubae (and broadly Malvaceae) could serve as a source of plant‐derived natural products that modulate bacterial resistance, i.e. a source of potential adjuvants of antibiotics. Copyright © 2009 John Wiley & Sons, Ltd.