Relapsing polychondritis studied by computed tomography

Computed tomographic findings in a patient with relapsing polychondritis are described. Collapse of the cartilage of the nose and calcification in cartilages of the ears were clearly demonstrated. CT scanning was also helpful in evaluating the tracheobronchial tree for airway compromise, which could prove fatal in this condition.     

Surface changes in Pseudomonas aeruginosa exposed to chlorhexidine diacetate and benzalkonium chloride

Pseudomonas aeruginosa strains 799 (wild-type) and 799/61 (envelope mutant) were exposed to chlorhexidine diacetate and benzalkonium chloride, and their hydrophobicity measured in a hydrocarbon (xylene) system. Both drugs induced changes in surface hydrophobic properties at concentrations well below those that inhibited cellular growth, A comparison of these findings has been made with a wild-type and an envelope mutant of Escherichia coli, both of which strains are more sensitive than Ps. aeruginosa to these drugs.     

Lung cancer audit in an Irish teaching hospital

Background Lung cancer is the most common cause of cancer-related death in Ireland. There are few complete data sets available as to the stage and cell type of lung cancers at time of presentation in Ireland. Aim To audit the lung cancers presenting to a large Dublin teaching hospital over a 12-month period. Method Prospective evaluation of all lung tumours presenting to our institution over a consecutive 12-month period. Results One hundred and ninety-eight lung cancers presented over the study period. There were 34 cases of small cell carcinoma and 150 cases of non-small cell carcinoma (NSCC). Fourteen patients were too ill or compromised at time of presentation for tissue confirmation. The most common cell type was squamous carcinoma. Eighty-four per cent of the NSCCs were either stage 3 or 4 at presentation. Conclusion Most lung cancers present late in the time course of the disease. Distribution of cell type and location are similar in Ireland and other developed countries.     

Phthalate ester-induced gubernacular lesions are associated with reduced insl3 gene expression in the fetal rat testis

Targeted inactivation of the insulin-like hormone 3 (insl3) gene in male mice results in altered gubernacular development, disrupted testis decent, and cryptorchidism. Cryptorchidism is a fairly common human malformation, being displayed in about three males per 100 at birth, but only a small percentage can be linked directly to genetic defects. The phthalate esters (PEs) are high production volume, ubiquitous environmental chemicals, some of which when administered during sexual differentiation, induce male rat reproductive tract malformations including gubernacular agenesis. We hypothesized that phthalate-induced gubernacular lesions likely result from an inhibition of insl3 gene expression. Three phthalates, di-n-ethylhexyl phthalate (DEHP), dibutyl phthalate (DBP) and benzyl butyl phthalate (BBP) were administered orally to the dam on gestation day 14 through 18 (GD14-18) and the fetal testes examined on GD18 for effects on steroid hormone production and insl3 gene expression. Compared to chemicals like vinclozolin, linuron, and prochloraz that act as AR antagonists and/or inhibit fetal Leydig cell testosterone production, only the three phthalates significantly reduced both ex vivo testosterone production and insl3 gene expression when quantified by real-time rtPCR. These results provide the first demonstration of PE-induced alteration of insl3 mRNA in the fetal male rat testis.     

Failure of Mycoplasma pneumoniae infection to confer protection against Mycoplasma genitalium: observations from a mouse model

Mycoplasma pneumoniae and M. genitalium are genomically distinct but share antigens that induce some serological cross-reactivity. Therefore, the possibility that M. pneumoniae infection of the human respiratory tract might provide immunity to M. genitalium infection of the genital tract was considered. Because of the difficulty of assessing this proposition in man, it was evaluated experimentally in a mouse model. Female BALB/c mice were susceptible to infection of the vagina with M. pneumoniae, whereas those infected previously in the oropharynx with M. pneumoniae were completely immune to infection of the vagina with this mycoplasma. However, all mice with such a respiratory tract infection were susceptible to infection of the vagina with M. genitalium. The findings suggest that an M. pneumoniae infection of the human respiratory tract is unlikely to influence infection of the genital tract by M. genitalium.