Scanning Electron Microscopy of Male Terminalia and Its Application to Species Recognition and Phylogenetic Reconstruction in the Drosophila saltans Group

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morphological aspects of rabbit masseter muscle after cervical sympathectomy

The objective of this paper was to study the effect of sympathetic innervation on morphological and histochemical aspects of skeletal muscle tissue. Rabbit masseter muscle was studied using histochemical and immunohistochemical methods for periods of up to 18 months post-sympathectomy. The morphological and enzymatic characteristics of control masseter muscles were similar on both the left and right sides. The main features were muscle fibres with a mosaic pattern and a predominance of type IIa fibres, followed by type I. Type IIb fibres showed very low frequency. Sympathectomized animals showed varying degrees of metabolic and morphological alterations, especially 18 months after sympathectomy. The first five groups showed a higher frequency of type I fibres, whilst the oldest group showed a higher frequency of type IIb fibres. In the oldest group, a significant variation in fibre diameter was observed. Many fibres showed small diameter, atrophy, hypertrophy, splitting, and necrosis. Areas with fibrosis were observed. Thus cervical sympathectomy induced morphological alterations in the masseter muscles. These alterations were, in part, similar to both denervation and myopathy. These findings indicate that sympathetic innervation contributes to the maintenance of the morphological and metabolic features of masseter muscle fibres.

Morphological aspects of tympanic bulla after ventral osteotomy in cats

To evaluate tympanic bulla healing after experimental ventral osteotomy in cats. Twenty adult cats were submitted to unilateral ventral bulla osteotomy and divided into two groups: cats of A1 group (n=10) were euthanized at 8 weeks and cats of A2 group (n=10), at 16 weeks postoperative. Signs of Horner's syndrome or damage to the inner ear were not found. Open-mouth radiographs taken in the immediate postoperative showed interruption in the contour of the larger compartment of the operated bulla. The result of Mcnemar'test was significant in A2 group (*p=0.0156). Macroscopic exams revealed that the operated bullae were similar to the normal ones, with preservation of the tympanic cavity. Connective tissue at the osteotomy site of the larger compartment was significantly found in the operated bullae in both groups (McNemar test: A1 p=0.0020*; A2 p=0.0078*). Histomorphometric analyses showed that the connective tissue length at the osteotomy site was shorter in A2 group than in the A1 group (Mann-Whitney test: p=0.0021*). Experimental ventral osteotomy did not alter significantly the tympanic bulla conformation and complete regeneration of tympanic bulla frequently did not occur before 16 weeks of postoperative period.

Voice disorders in teachers: clinical, videolaryngoscopical, and vocal aspects

Dysphonia is more prevalent in teachers than among the general population. The objective of this study was to analyze clinical, vocal, and videolaryngoscopical aspects in dysphonic teachers. Ninety dysphonic teachers were inquired about their voice, comorbidities, and work conditions. They underwent vocal auditory-perceptual evaluation (maximum phonation time and GRBASI scale), acoustic voice analysis, and videolaryngoscopy. The results were compared with a control group consisting of 90 dysphonic nonteachers, of similar gender and ages, and with professional activities excluding teaching and singing. In both groups, there were 85 women and five men (age range 31-50 years). In the controls, the majority of subjects worked in domestic activities, whereas the majority of teachers worked in primary (42.8%) and secondary school (37.7%). Teachers and controls reported, respectively: vocal abuse (76.7%; 37.8%), weekly hours of work between 21 and 40 years (72.2%; 80%), under 10 years of practice (36%; 23%), absenteeism (23%; 0%), sinonasal (66%; 20%) and gastroesophageal symptoms (44%; 22%), hoarseness (82%; 78%), throat clearing (70%; 62%), and phonatory effort (72%; 52%). In both groups, there were decreased values of maximum phonation time, impairment of the G parameter in the GRBASI scale (82%), decrease of F0 and increase of the rest of acoustic parameters. Nodules and laryngopharyngeal reflux were predominant in teachers; laryngopharyngeal reflux, polyps, and sulcus vocalis predominated in the controls. Vocal symptoms, comorbidities, and absenteeism were predominant among teachers. The vocal analyses were similar in both groups. Nodules and laryngopharyngeal reflux were predominant among teachers, whereas polyps, laryngopharyngeal reflux, and sulcus were predominant among controls.

Staphylococcal enterotoxins: molecular aspects and detection methods

Members of the Staphylococcus genus, especially Staphylococcus aureus, are the most common pathogens found in hospitals and in community-acquired infections. Some of their pathogenicity is associated with enzyme and toxin production. Until recently, S. aureus was the most studied species in the genus; however, in last few years, the rise of infections caused by coagulase-negative staphylococci has pointed out the need for further studies on virulence factors that have not yet been completely elucidated so as to better characterize the pathogenic potential of this group of microorganisms. Several staphylococcal species produce enterotoxins, a family of related proteins responsible for many diseases, such as the toxic-shock syndrome, septicemia and food poisoning. To this date, 23 different enterotoxin types have been identified besides toxic-shock syndrome toxin-1 (TSST-1), and they can be divided into five phylogenetic groups. The mechanism of action of these toxins includes superantigen activity and emetic properties, which can lead to biological effects of infection. Various methods can detect genes that encode enterotoxins and their production. Molecular methods are the most frequently used at present. This review article has the objective to describe aspects related to the classification, structure and regulation of enterotoxins and toxic-shock syndrome toxin-1 detection methods.