Yavuz Selim Pata

The effect of L-carnitine on the prevention of experimentally induced myringosclerosis in rats

The objective of this study was to investigate the possible effect of L-carnitine on the prevention of experimentally induced myringosclerosis. Twenty Sprague-Dawley rats were bilaterally myringotomized. The rats were divided into two groups randomly: group 1 which were intraperitoneally administered saline and group 2 which were intraperitoneally administered L-carnitine. Blood samples were collected for biochemical evaluation and the tympanic membranes were harvested after 28 days. Histopathological and immunohistochemical evaluation were done under light microscopy. The mean malondialdehyde levels were 3.9+/-0.9 in group 2, and 7.9+/-1.1 in group 1 (P<0.001), nitric oxide levels were 25.6+/-6.4 in group 2 and 30.8+/-8.2 in group 1 (P=0.14) and acetylcholinesterase was 1035+/-60 in group 2 and 678+/-35 in group 1 (P=0.001). Myringosclerosis was more frequent and severe in group 1 than group 2 (P<0.007). Immunoreactivity was seen in 16 of 20 tympanic membranes in group 2 and six of 20 tympanic membranes in group 1 (P=0.005). We conclude that L-carnitine diminishes the occurrence of myringosclerosis in rats after myringotomy possibly by antioxidant activity and decreasing the formation of reactive oxygen species.

Glutathione S-transferase gene polymorphisms in presbycusis.

Hypothesis: Glutathione and glutathione-related antioxidant enzymes are involved in the metabolism and detoxification of cytotoxic and carcinogenic compounds as well as reactive oxygen species. Reactive oxygen species generation occurs in prolonged relative hypoperfusion conditions such as in aging. The etiology of presbycusis is much less certain; however, a complex genetic cause is most likely. The effect of aging shows a wide interindividual range; we aimed to investigate whether profiles of (glutathione S-transferase (GST) M1, T1 and P1 genotypes may be associated with the risk of age-related hearing loss. Patients and Methods: We examined 68 adults with presbycusis and 69 healthy controls. DNA was extracted from whole blood, and the GSTM1, GSTT1 and GSTP1 polymorphisms were determined using a real-time polymerase chain reaction and fluorescence resonance energy transfer with a Light-Cycler Instrument. Associations between specific genotypes and the development of presbycusis were examined by use of logistic regression analyses to calculate odds ratios and 95% confidence intervals. Results: Gene polymorphisms at GSTM1, GSTT1, and GSTP1 in subjects with presbycusis were not significantly different than in the controls (p > 0.05). Also, the combinations of different GSTM1, GSTT1, and GSTP1 genotypes were not an increased risk of presbycusis (p > 0.05). Conclusion: We could not demonstrate any significant association between the GSTM1, GSTT1, and GSTP1 polymorphism and age-related hearing loss in this population. This may be because of our sample size, and further studies need to investigate the exact role of GST gene polymorphisms in the etiopathogenesis of the presbycusis.

Asymptomatic bilateral mixed-type laryngocele and laryngeal carcinoma

A laryngocele is an abnormal dilatation of the laryngeal saccule. The relationship between layngoceles and laryngeal carcinoma is still debated. We present the case of a 45-year-old male patient with bilateral asymptomatic laryngocele and laryngeal squamous cell carcinoma. We discuss the possible etiopathogenetic influence of increased intralaryngeal pressure with preoperative CT and explorative findings, and the current literature is reviewed.

Serum leptin levels in patients with allergic rhinitis

OBJECTIVE: To investigate the serum leptin levels in patients with allergic rhinitis during the symptomatic period. STUDY DESIGN AND SETTING: A randomized, prospective study was performed on 26 adult patients with allergic rhinitis and 20 control subjects with similar age, sex and body mass index in a tertiary otolaryngology center. RESULTS: Leptin levels were 28.8 ± 14.1 ng/mL in the patients with allergic rhinitis, and 20.8 ± 13.5 ng/mL in the control group respectively. The difference between the groups was statistically significant (p = 0.04). CONCLUSION: Serum leptin levels were found to be significantly higher in patients with allergic rhinitis in symptomatic period. SIGNIFICANCE: Apart from its primary role in the regulation of body weight and energy expenditure, leptin may have a role in the inflammatory process of the allergic rhinitis.

Has cerumen a protective role in recurrent external otitis

PURPOSE We investigated the bactericidal activity of the cerumen in patients with recurrent otitis externa. MATERIALS AND METHODS Cerumen samples were collected from 2 groups. Group A (n = 20) consisted of patients with recurrent otitis externa (2 or more acute otitis externa attack in the current year) and group B (n = 30) consisted of cerumen from a healthy population. We examined the bactericidal activity against the common microorganisms (Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa, and Enterococcus) that encounter the recurrent otitis externa. RESULTS A significant decrease in the count of S epidermidis was observed in group A (P <.05) and B (P <.01) was observed. A comparison of decreases and increases in the percentages of microorganisms between the groups A and B showed that there was a significant difference only in the count of E coli (P <or=.05). The count of E coli decreased in cerumen suspension in group A, but it increased in the normal population. CONCLUSION We did not confirm that cerumen from patients with recurrent otitis externa had less bactericidal activity than from a healthy population.

Prevention of laryngotracheal stenosis with carnitine after tracheotomy: an experimental study on rats

OBJECTIVE We investigated the effect of carnitine on wound healing of trachea in tracheotomyzed rats. This study was undertaken to test the hypothesis that treatment with carnitine would protect the wound tissue, which was evaluated by measuring nitrite and nitrate, thus nitric oxide, malondialdehyde and cholinesterase in blood, and examining the histopathological changes. METHODS Standard vertical tracheotomy was performed on 24 Wistar-Albino type rats. Then the animals were randomly divided into two groups; group A (the study group) was administered intraperitoneal carnitine 100 mg/kg for 10 days; group B (the control group) was administered intraperitoneal saline for 10 days. On the 10th day, all animals were decanulated. Three weeks later, cardiac blood samples were taken for biochemical assays and trachea specimens were harvested for histopathologic examination. RESULTS In the carnitine-administered group, granulation tissue thickness resulting from the wound healing in the level of tracheotomy incision was lower compared to the control group (P < 0.01). When serum malondialdehyde levels were considered, a lower malondialdehyde level was found in the carnitine-administered group (P < 0.01). However, serum nitric oxide levels were close to each other in both groups (P > 0.05), while serum cholinesterase level was higher in the carnitine-administered group than in the control group (P < 0.01). CONCLUSION Carnitine treatment partially prevents and significantly reduces the severity of tracheotomy induced laryngotracheal stenosis.

Serum nitrite/nitrate and arginase levels in patients with allergic rhinitis

Nitric oxide (NO) plays an important role in the regulation of upper respiratory function. Patients with untreated allergic rhinitis (AR) have an increased level of NO in the nasal cavity compared to normal individuals. We aimed to investigate serum levels of arginase and NO metabolites nitrite/nitrate in patients with AR during the symptomatic period. The patient and control groups consisted of 14 males and 12 females (mean age: 29, range: 20–40 years), and 10 males and 10 females (mean age: 27, range: 22–38 years), respectively. Nitrite/nitrate levels were 0.98 ± 0.33 ng/ml in the patients with AR, and 0.78 ± 0.26 ng/ml in the control group (p = 0.03). Arginase levels were 28.8 ± 14.1 ng/ml in the patients with AR, and 20.8 ± 13.5 ng/ml in the control group. The difference between the groups was statistically insignificant (p = 0.24). Our results support the view that NO plays an important role in the pathogenesis of AR, and NO metabolites may be used as a marker for monitoring the disease activity and therapy.

GENETIC POLYMORPHISM OF N-ACETYLTRANSFERASE 2 IN THE SUSCEPTIBILITY TO LARYNGEAL SQUAMOUS CELL CARCINOMA

The purpose of this study was to investigate whether polymorphism of N‐acetyltransferase 2 (NAT2) genotypes are associated with the risk of laryngeal squamous cell carcinoma (SCC).

Autonomic nervous system evaluation using heart rate variability parameters in vasomotor rhinitis patients.

OBJECTIVE To evaluate the autonomic nervous system in vasomotor rhinitis patients using heart rate variability parameters. PATIENTS AND METHODS The heart rate variability parameters (SDANN, SDNN, SDNN index, RMSSD, pNN50, triangular index) of 26 patients with vasomotor rhinitis were compared with those of 25 control subjects. RESULTS The decrease in the SDANN and SDNN index in the vasomotor rhinitis patients is statistically significant. Likewise, the SDNN and triangular index decreased but not to a statistically significant degree. The decrease in rMSSD and pNN50, which are signs of parasympathetic nervous system hyperactivation, in the patient group is statistically significant when compared with the control group (p < .005). CONCLUSION The results of this study suggest that there might be an abnormality in the autonomic nervous system of vasomotor rhinitis patients, which might be due to a hyperactive parasympathetic nervous system.

Expression of inducible nitric oxide synthase in antrochoanal polyps

OBJECTIVE Antrochoanal polyp (ACP) is a polypoid lesion originating from the maxillary sinus, emerging from the ostium and extending to the choana. Although the etiologic causes of ACP are not known completely, it presents a fairly uniform clinical appearance. Nitric oxide (NO) has an important role in non-specific immunoreactions and inflammation in various tissues and has a main regulatory role in airway function and seems to involve in pathomechanism of several respiratory system diseases. NO is synthesized by the effect of three isoforms of nitric oxide synthase i.e. inducible NOS (iNOS). Some studies revealed that ACP has some different characteristics from the ordinary nasal polyps. In the present study, in order to compare ACP with allergic and non-allergic nasal polyps (NANP), we detected and localized the iNOS expression and also evaluate some histological parameters. METHODS Twenty-six cases were chosen from the files and four controls were used. The cases were separated as follows: normal inferior turbinate mucosa as control (n=4) ACPs (n=8), allergic nasal polyps (ANP) (n=9), and NANP (n=9). Five-micrometer thick sections were prepared from the paraffin sections of polyps and normal nasal mucosa to quantify the iNOS expression. iNOS protein was observed in the cytoplasm of epithelial and stromal inflammatory cells. iNOS protein expression in the groups was assessed according to the intensity of staining and histomorphological parameters, oedema, lymphocytic and eosinophilic cell infiltration were detected semi quantitatively. RESULTS iNOS expressions, either stromal or epithelial, were not different from each other among the four groups. Although it is not statistically significant, we noted that ANP and ACP frequently showed moderate and severe iNOS protein expression in epithelial and stromal parts when compared with NANPs and controls. Also, iNOS expression was significantly higher in the stroma of the ANPs than NANPs (P=0.012). CONCLUSIONS ACPs and ANPs have frequently showed moderate and significant epithelial and stromal iNOS expression. Further studies are needed in large groups to elucidate differences between ACP and the other nasal polyps.