The preventive effect of N-nitro L-arginine methyl ester in experimentally induced myringosclerosis

Objective

The purpose of this study was to investigate the antiinflammatory and antifibrotic effects of N-nitro l-arginine methyl ester (l-NAME) in experimentally induced myringosclerosis.

Methods

Twenty Wistar albino rats were bilaterally myringotomized and divided randomly into four groups, each including five rats. Group I received no treatment, Group II was treated with topical saline solution, Group III received topical l-NAME and Group IV received intraperitoneally administered l-NAME. After 2 weeks, the tympanic membranes were examined and scored by otomicroscopy regarding the extent of the myringosclerosis. Then the tympanic membranes were harvested and evaluated histopathologically by light microscopy. The intensity of inflammation and degree of myringosclerosis were evaluated, the mean thickness of tympanic membranes were also measured.

Results

The tympanic membranes of Groups I and II showed extensive myringosclerosis in contrast to those of Groups III and IV which had significantly less or no changes (p < 0.05). The inflammation and fibroblastic activity of the lamina propria in the tympanic membranes of Groups III and IV were found to be significantly less pronounced (p < 0.05). The tympanic membranes were found to be significantly thicker in Groups I and II when compared with Groups III and IV (p < 0.05).

Conclusion

Our results showed that both topical and intraperitoneal applications of l-NAME supressed inflammation, reduced fibroblastic proliferation and decreased the formation of myringosclerosis in myringotomized rat tympanic membranes.     

Late crust formation as a predictor of healing of traumatic,dry, and minor-sized tympanic membrane perforations

Objective

The goal of this study was to evaluate the effects of crust formation on the healing of traumatic, dry, and minor-sized tympanic membrane perforations (TMPs) in humans.

Study design

Case series with a chart review.

Setting

Tertiary university hospital.

Materials and methods

The clinical records of patients with traumatic TMPs who met the case selection criteria were retrieved and categorized according to the presence of a crust and the timing of crust formation into three groups: no crust, early crust formation, and late crust formation. Healing outcomes (i.e., healing rate and time) in the three groups were analyzed.

Results

In total, 83 patients were analyzed. The perforation closure rates were 92%, 100%, and 78% in the groups with no-crust, early crust formation, and late crust formation, respectively. No significant difference was seen between the groups with no-crust and with late crust formation (p > 0.05). By contrast, closure rates differed significantly between the early and late crust formation groups (p < 0.05). Overall, the no-crust and early crust formation groups showed shorter healing times compared with the late crust formation group (p < 0.05). However, closure times did not differ significantly between groups with early crust formation and no crust (p > 0.05).

Conclusions

Crust formation at the margin of a traumatic TMP may serve as a predictor of healing outcome. Compared with perforations with early crust formation or no crust, late crust formation can result in delayed healing and failure to close completely.     

Fascia implantation with fibroblast growth factor on vocal fold paralysis

Purpose

The purpose of this prospective study was to determine the effect of autologous transplantation of fascia into the vocal fold (ATFV) with controlled release of basic fibroblast growth factor (bFGF) on unilateral vocal fold paralysis (UVFP) in a rat model.

Materials and methods

Unilateral recurrent laryngeal nerve (RLN) section was performed on 15 rats. Ten rats received an autologous fascia implant and gelatin hydrogel with or without bFGF (1 μg) to their larynxes (fascia only, “fascia group”; bFGF + fascia, “fascia + bFGF group”), while the rest underwent RLN transection (“RLN section group”). Four months later, evaluation of the laryngeal glottal gap and histological analysis were performed.

Results

The glottal gap was significantly reduced in the fascia + bFGF group, and fat volume increased significantly relative to the RLN section. The volume of the remaining fascia in the bFGF + fascia group was significantly greater than that of the fascia group.

Conclusions

ATFV with controlled release of bFGF may compensate for diminished laryngeal volume in UVFP by reducing resorption of the implanted fascia and increasing fat volume. Our findings suggest that this modality may represent an attractive option for treating UVFP.     

Protective effect of trimetazidine on amikacin-induced ototoxicity in rats

Objective

Aminoglycoside antibiotics are known to have ototoxic effects and may induce sensorineural hearing loss. This study investigated the protective effect of trimetazidine, which has antioxidant and cytoprotective properties, against amikacin ototoxicity.

Methods

Thirty-two male rats were divided into four groups – amikacin, amikacin + trimetazidine, trimetazidine, and control groups. Trimetazidine, 10 mg/kg per day, was given for 14 days by oral gavage. Amikacin, 600 mg/kg per day, was also given for 14 days, by the intramuscular route. Distortion product otoacoustic emission (DPOAE) and auditory brainstem response (ABR) tests were applied to the rats for hearing assessment. At the termination of the study, the biochemical parameters were calculated to evaluate the oxidative status.

Results

The DPOAE values of the amikacin group were significantly lower on the 7th and 14th days than those of the trimetazidine + amikacin group and there was an increase in the ABR thresholds. The ABR thresholds for the amikacin group on the 7th and 14th days were significantly higher than the levels on the first day of the study, while there was no significant increase in those values in the trimetazidine + amikacin group. The total oxidant status (TOS) and oxidant status index (OSI) values of the amikacin group were significantly higher than those of the trimetazidine + amikacin group. The total antioxidant status (TAS) values of the amikacin group were lower than those of the trimetazidine + amikacin group.

Conclusions

The audiologic tests and biochemical parameters investigated in this study both point to the protective effect of trimetazidine against amikacin-induced ototoxicity.     

Effects of caffeic acid phenethyl ester on wound healing of nasal mucosa in the rat: an experimental study

Purpose

Wound healing of the nasal mucosa is a highly complex process that restores the anatomical and functional integrity of tissue that has been exposed to trauma. In this experimental study, our aim was to use histopathological examination to investigate the effects of caffeic acid phenethyl ester on the wound healing of rat nasal mucosa after mechanical trauma.

Materials and methods

The rats were randomly divided into 3 experimental groups: a non-treated group (n = 7), a control saline group (n = 7) and a caffeic acid phenethyl ester group (n = 7). The non-treated group received no treatment for 15 days. The second group was administered saline (2.5 mL/kg, intraperitoneal) once a day for 15 days. The third group received caffeic acid phenethyl ester intraperitoneally at a dose of 10 μmol/kg once a day for 15 days. At the beginning of the study, unilateral mechanical nasal trauma was induced on the right nasal mucosa of all rats in the three groups using a brushing technique. Samples were stained using hematoxylin and eosin solution and were examined by a pathologist using a light microscope.

Results

The severity of inflammation was milder in the caffeic acid phenethyl ester group compared with that in the non-treated and saline groups (P < 0.05). The subepithelial thickness index was lower in the experimental group (P < 0.05). Goblet cell and ciliated cell loss was substantially reduced in the experimental group compared with the non-treated and saline groups (P < 0.05).

Conclusions

Caffeic acid phenethyl ester decreases inflammation and the loss of goblet cells and ciliated cells. Therefore, caffeic acid phenethyl ester has potential beneficial effects on the wound healing of nasal mucosa in the rat.     

The use of large volume low pressure nasal saline with fluticasone propionate for the treatment of pediatric acute rhinosinusitis

Objectives

Fluticasone propionate and nasal saline irrigation have been used in the treatment of sinonasal diseases for a long time. Our study investigates the effect of the combination of large volume low pressure nasal saline irrigation and fluticasone propionate for the treatment of pediatric acute rhinosinusitis.

Methods

Ninety-one pediatric patients with acute rhinosinusitis were included in our study. The patients were randomized into two groups. The first group (n = 45) was treated with standard therapy (antibiotherapy + nasal decongestant) for 2 weeks, the second group was treated with the large volume low pressure nasal saline + fluticasone propionate combination for 3 weeks. The clinical scores, radiologic evaluations (X-ray Waters view), peak nasal inspiratory flow (PNIF) measurements, total symptom scores and hematologic parameters (WBC, CRP, ESR) of the patients were evaluated and compared.

Results

There were no significant differences in between the two groups regarding age, gender, height and weight. Even though the clinical scores of Group 2 improved more rapidly, there were no significant differences in between groups regarding clinical scores by the 21st day. There were no significant differences in post treatment radiologic evaluations (Waters graphy). Both groups had significant improvement of their post treatment PNIF values, yet the improvement was more marked in Group 2 than in Group 1. The rhinorrhea, nasal congestion, throat itching and cough symptoms improved more rapidly in Group 2 than in Group 1. Post-treatment nose itching and sneezing symptoms were significantly less in Group 2. The values of hematologic parameters were significantly reduced at the end of the 3rd week in both groups.

Conclusions

Our study is a first in investigating the combined use of large volume low pressure nasal saline and fluticasone propionate in acute pediatric rhinosinusitis, and the results reveal that the combination therapy was effective. Low pressure large volume nasal saline + fluticasone propionate combination can be employed as a new line of therapy for the treatment of pediatric acute rhinosinusitis, either by itself or combined with standard therapy.     

Erratum to “Is sensorineural hearing loss with chronic otitis media due to infection or aging in older patients?” [Auris Nasus Larynx 36 (2009) 269–273]

Objective

To clarify true incidence of sensorineural hearing loss in ears with chronic otitis media (COM).

Methods

Bone conduction (BC) hearing thresholds of 180 preoperative patients (207 ears) with COM and 226 normal individuals (289 ears) were measured by audiometry, and the percentage of ears with BC thresholds being higher than normal range was evaluated in the COM group. In the COM group, the size of the perforation on the eardrum (n = 196) and the cross-sectional area of the mastoid air cells based on the axial CT image (n = 103) were also measured and correlated with the results of BC threshold.

Results

The percentage of ears with BC thresholds being higher than normal range calculated from comparison to the control group tended to increase with age, ranging from 4.5% in the 20s to 34.1% in the 60s with an average of 26.6%. The increase in the BC thresholds did not correlate with the size of eardrum perforation, but correlated well with the size of the mastoid air cells.

Conclusion

These results may suggest that all measures for early cure, including surgery, should be considered as early as possible for patients with COM.     

The clinical status of the eardrum: An inclusion criterion for the treatment of chronic secretory otitis media in children

Objective

To investigate if the clinical status of the eardrum could be an inclusion criterion for the therapy of chronic secretory otitis media (CSOM). To compare the results of treating CSOM by adenoidectomy and by adenoidectomy in combination with tympanostomy tubes in two groups of patients chosen according to that criterion.

Methods

161 ears in 87 children were treated for CSOM. An otomicroscopic examination showed there were no pathological changes on the tympanic membrane (signs of adhesive process, malleus rotation, and dangerous attic retractions). The patients were randomly divided into two groups: the first group of 59 ears was treated by myringotomy and tympanostomy tubes and adenoidectomy, while the other group of 102 ears was treated only by adenoidectomy. At least 6 months after the treatment, otomicroscopy and audiological assessments were performed in order to show the resolution of the middle ear effusion (MEE), audiological results and incidence of clinical sequelae of the eardrum.

Results

The resolution of MEE by adenoidectomy alone was not significantly different from the results of treatment by adenoidectomy and tympanostomy tubes (z = 1.565; p = 0.0587).There were no differences in pure tone audiometry between the two methods of treatment. Only at the frequency of 2000 Hz (t = 2.173; p = 0.031) in treatment with adenoidectomy and tympanostomy tubes the values of air-bone gap (ABG) were lower.Sequelae: scars of the eardrum (chi-square = 28.107; ss = 1; p < 0.001) and attic retractions (chi-square = 4.592; ss = 1; p = 0.032) were more often in treatment with tubes. The incidence of clinical sequelae on the eardrum after treatment by tubes was commented on.

Conclusion

A criterion that could influence the approach to the therapy of CSOM in children.     

Management of neck metastases in T2N0 lip squamous cell carcinoma

Background

Prophylactic neck dissection (PND) is indicated when the chance of occult lymph node metastases from head and neck tumors is significant. There is no consensus regarding which tumor size PND would be indicated in cases of lip cancer.

Methods

A total of 139 patients with surgically treated lip cancer were selected. The size of the lesion (T) and the presence of lymph node metastases (N) were assessed by examining the medical records. For analysis purposes, the T2 group was divided into T2a (2 to 3 cm) and T2b (3 to 4 cm).

Results

The following distribution of incidence of neck metastases was observed in the study groups: 11.7% in T1, 9% in T2a, 43.7% in T2b, and 52.2% in T3 + T4. Statistical comparison of the groups (p) revealed the following results: T2a X T2b = 0.03; T2a X T3 + T4 = 0.001.

Conclusion

PND is indicated for tumors larger than 3 cm.     

Results of Baha® implantation using a small horizontal incision

Purpose

Techniques for Baha® implantation continue to evolve. The Weber technique, utilizing a 1.5 cm horizontal incision for Baha® implantation is evaluated.

Methods

Retrospective review of patients undergoing Baha® implantation by a single surgeon over three years.

Results

33 Baha®s implanted in 30 patients. Fourteen used an Inverted J (IJ) incision with an anteriorly-based skin-flap, 13 with the Weber technique (W). Five were not included as other techniques were used. Demographics and weeks to activation (14.58 vs 13.4, p = 0.12) were similar. There were no differences in the number of patients with minor complications (5 vs 2, p = 0.22) or number of minor complications (20 vs 4, p = 0.09). One patient in the IJ Group required operative revision for overgrowth. There were no infections in the IJ Group, and one requiring oral antibiotics in the W Group. Follow-up was longer in the IJ Group (41 vs 13 weeks, p = 0.016), no complications occurred after 14 weeks post-op. Mean operative times were similar (43 vs 39 min, p = 0.59). There were no cases of skin flap necrosis in either group.

Conclusion

A small incision for Baha® implantation proved as effective, without increased complications as a skin-flap based technique.     

Comparison of nasal mucociliary clearance in adenoid hypertrophy with or without otitis media with effusion

Objective

To investigate pre- and postoperative mucociliary clearance in patients with adenoid hypertrophy or combined with otitis media with effusion.

Methods

Patients were divided into two groups: Group 1—patients with adenoid hypertrophy (AH), and Group 2—patients with AH and otitis media with effusion (AHOME). In all patients, AH size was recorded, and the Andersen saccharin and methylene blue tests were conducted before and 1 month after surgery to obtain mucociliary clearance time (MCT). Nasal cavity length was measured intraoperatively to establish mucociliary clearance velocity (MCV). Patients with allergic rhinitis, active infection, and history of nasal or ear surgery were excluded.

Results

This study included 64 patients with a mean age of 8.34 ± 2.98 years (range: 3–18 years). Pre- and postoperative MCT were 14.60 ± 4.83 and 9.48 ± 2.63 min in Group 1 and 16.03 ± 4.31 and 12.12 ± 3.78 min in Group 2, respectively. Pre- and postoperative MCV were 0.77 ± 0.30 and 1.16 ± 0.42 mm/min in Group 1 and 0.67 ± 0.16 and 0.89 ± 0.28 mm/min in Group 2, respectively. MCT and MCV were significantly improved postoperatively in both groups (p < 0.001). In addition, the postoperative MCT and MCV of Group 1 were significantly better than those of Group 2 (p < 0.001). Exposure to cigarette smoking and adenoid size had negative correlations with mucociliary clearance.

Conclusions

Otitis media was associated with impaired mucociliary clearance and further studies should be performed to demonstrate the causes of this deficiency.     

Loop overlay tympanoplasty for anterior or subtotal perforations

Objective

To report our experience with “loop overlay” tympanoplasty, a modified overlay technique with a superiorly based skin flap, for the reconstruction of anterior, subtotal or total tympanic membrane (TM) perforations.

Methods

Retrospective review of patients undergoing loop overlay tympanoplasty from March 1998 to February 2007 was performed. Four hundred and twenty-nine patients who underwent loop overlay tympanoplasty and then follow-up visits a minimum of 6 months later were included in this study. Hearing test results were reported using a four-frequency (0.5, 1, 2, and 3 kHz) pure tone average air–bone gap. The outcome was considered successful if the TM was intact without lateralization or anterior blunting after the follow-up visit.

Results

There was a 98.8% success rate. There was no graft lateralization, anterior blunting, neocholesteatoma, or sensorineural hearing loss. The mean preoperative to postoperative four-tone air–bone gap improved from 23.5 to 8.1 dB, which is a mean gain of 15 dB; this was statistically significant (p < 0.001, paired sample t-test).

Conclusion

The loop overlay graft method is a safe and effective technique for reconstruction of anterior, subtotal or total TM perforations, with excellent graft take and significant improvement of hearing. It provides a precise replacement of the flap and a preserved healing plane.     

Endoscopic versus microscopic approach to type 1 tympanoplasty in children

Objectives

We investigated the outcomes of the endoscopic versus microscopic approach to type 1 tympanoplasty in pediatric patients.

Methods

In this retrospective study, the outcomes of 61 ears of 60 pediatric patients (33 male and 27 female) who underwent type 1 tympanoplasty were evaluated. One patient underwent a bilateral operation. The age range of the patients was 7–16 years. Group 1 underwent tympanoplasty with an endoscopic technique (n = 32), and Group 2 underwent tympanoplasty with the conventional microscopic technique (n = 29). A boomerang-shaped chondroperichondrial graft was used in both groups. The outcomes were analyzed in terms of the hearing gain, duration of surgery, and graft success rate.

Results

In both groups, the postoperative air–bone gap (ABG) was significantly lower than the preoperative ABG. There were no significant differences between the preoperative and postoperative ABG values (in dB) in either group. The mean operative duration in Group 1 was significantly lower than that in Group 2 (51.37 vs. 67.03 min, respectively). In the preoperative evaluation, 65.6% of patients in Group 1 had larger perforations and 34.4% had smaller perforations. In Group 2, 58.6% and 41.3% of patients had larger and smaller perforations, respectively. Perforations were detected in two (6.25%), four (12.50%), and four (12.50%) of the patients in Group 1 at postoperative months 1, 6, and 12, respectively. Perforations were detected in two (5.71%) patients in Group 2 at postoperative months 1, 6, and 12. At 12 months postoperatively, there were smaller perforations in four (12.5%) of the children in Group 1 and in two (5.71%) of the children in Group 2. The difference between the perforation conditions (larger vs. smaller) was not significant in either group. The preoperative and postoperative increases in the ABG were associated. The operative duration was shorter in Group 1 than in Group 2.

Conclusion

In pediatric patients undergoing type 1 tympanoplasty, especially if the external ear canal is narrow and the anterior canal wall is prominent, the endoscopic and microscopic approaches appear to give equal results in terms of easy visualization of the entire tympanic membrane and no requirement for extra intervention to evaluate the ossicular system. A shorter operative duration is an advantage of the endoscopic tympanoplasty technique.     

Air pressure-sensing ability of the middle ear—Investigation of sensing regions and appropriate measurement conditions

Objective

To study the association between ear diseases and the ability of the middle ear to sense air pressure changes, we elucidated the appropriate conditions for measurements and confirmed the pressure-sensing regions while quantitatively assessing the pressure-sensing ability of normal ears and of ears with traumatic perforation of the tympanic membrane.

Methods

In 318 normal ears (159 volunteers), an air pressure of 40 daPa s⁻¹ was loaded on to the external auditory canals to measure the minimum pressure sensed by subjects as a result of air pressure changes. The minimum pressure was defined as the minimum sensory threshold for air pressure loading (MSTAP; daPa). In 40 of 318 normal ears (20 volunteers), the MSTAP was measured at 10 daPa s⁻¹. Next, topical anesthesia was administered to 5 normal ears (5 volunteers), and the MSTAP was measured. In 7 ears with traumatic tympanic membrane perforation (7 cases), the MSTAP was also measured at the first medical examination.The data were analyzed using Stat View 5.0 (SAS Institute Inc., Cary, NC, USA). To test the significance of the data, the Mann–Whitney U-test and the Wilcoxon test were used.

Results

The mean (±S.D.) MSTAP at 40 daPa s⁻¹ was −39.2 ± 12.2 daPa with negative pressure and 39.5 ± 12.4 daPa with positive pressure. At 10 daPa s⁻¹, the MSTAP was −70.3 ± 25.0 daPa with negative pressure and 72.5 ± 22.7 daPa with positive pressure, and both the mean and S.D. values were higher than those obtained at 40 daPa s⁻¹. Briefly, the MSTAP at 40 daPa s⁻¹ produced less variance than that at 10 daPa s⁻¹.The MSTAP demonstrated gender- and age-related variations. Moreover, it increased after topical anesthesia was administered to the tympanic membrane. The MSTAP in patients with traumatic tympanic membrane perforation was −205.0 ± 26.3 daPa with negative pressure and 206.0 ± 26.7 daPa with positive pressure, and was significantly higher than that observed in case of normal ears.

Conclusion

For obtaining accurate measurements while estimating the pressure-sensing ability of the middle ear, the rate of pressure loading should be considered. Although we assume that the middle ear has pressure-sensing regions other than the tympanic membrane, we conclude that the tympanic membrane is the most sensitive pressure-sensing region in the middle ear.     

Long-term follow-up of otitis media with effusion in children: Comparisons between a ventilation tube group and a non-ventilation tube group

Objective

The objective of this study was to investigate the long-term outcomes in children with otitis media with effusion who received either medical treatment or ventilation tubes.

Methods

We retrospectively analyzed the medical records of 89 bilateral cases of otitis media with effusion in children who were recommended to receive ventilation tube insertion and were followed up for more than 5 years. Tympanic membrane was inspected by otoscopic examination. Hearing was evaluated with pure tone audiometry. The mean duration of follow-up was 8.4 years (range, 5.2–15.7 years). Twenty-three children were treated without surgery, while 22 were treated once by ventilation tube insertion and 44 were treated more than once by ventilation tube insertion.

Results

At the fifth year of follow-up, both groups of children who underwent ventilation tube insertion had more frequent tympanic membrane abnormalities than the medication group (8.7% in those treated without surgery, 72.7% in those treated once by ventilation tube insertion, and 88.6% in those treated more than once by ventilation tube insertion). Common tympanic membrane abnormalities were retraction (27.0%) and tympanosclerotic plaque (23.6%), regardless of the treatment modality. At the fifth year follow-up, the average air-conduction threshold was 10.0 dB (± 6.5 dB) in patients treated without surgery, 15.9 dB (± 11.2 dB) in patients treated once by ventilation tube insertion, and 17.8 dB (± 7.6 dB) in those treated more than once by ventilation tube insertion. The audiological difference was significant when we compared the hearing level of children treated by medication without surgery to the two ventilation tube groups.

Conclusion

Though ventilation tube insertion can resolve hearing loss quickly, there were more tympanic membrane abnormalities and a decline in hearing levels in our ventilation tube insertion group vs. the observation group measured 5 years later. Physicians should therefore be cautious when applying a ventilation tube in patients with otitis media with effusion and should explain the risks to patients who are a candidate for repeated ventilation tube insertion.     

Effects of arginine vasopressin on auditory brainstem response and cochlear morphology in rats

Objective

This study was conducted to evaluate the relationship between hearing and cochlear histopathology after arginine vasopressin administration in rats.

Methods

A total of 30 Wistar rats were injected with either 0.02 unit/g of arginine vasopressin or the same amount of isotonic saline solution. The initial auditory brain stem response threshold was recorded and additional measurements were made at 10, 30, 60, and 90 min after injection of arginine vasopressin or isotonic saline solution. The threshold for each timepoint was compared with the initial threshold. Histological quantitative assessment of endolymphatic hydrops in the cochlea was performed using light microscopy and assessment of the basal, intermediate, and marginal cells of the stria vascularis was performed with electron microscopy.

Results

The auditory brain stem threshold 60 min after arginine vasopressin injection increased significantly in comparison with the initial threshold (P < 0.05). Although the index for endolymphatic hydrops in rats administered arginine vasopressin was not different from that in controls (P > 0.05), vacuoles in the intermediate cells were increased significantly in the treated rats (P < 0.01).

Conclusion

Hearing impairment was detected without endolymphatic hydrops in rats administered arginine vasopressin. An increase of vacuoles in the intermediate cells may account for the hearing impairment induced by arginine vasopressin injection.     

Expression of claudin-3 in the esophagus and larynx of rat reflux model

Objective

The aim of this study was to investigate the association between laryngeal expression of claudin-3 and laryngopharyngeal reflux (LPR) in a rat reflux model.

Methods

Eight Wistar rats were divided into two groups. Four rats underwent total esophageal myectomy to induce reflux, and the remainder underwent a sham operation as a control. All animals were sacrificed 12 weeks after surgery to perform tissue histology and Western blot analysis.

Results

Lymphocyte infiltration increased significantly in the study group in both esophageal and laryngeal samples (P = 0.001, 0.002, respectively). Both esophageal and laryngeal expressions of claudin-3 were significantly lower in the study group when compared with that in the control group (P = 0.045, 0.037, respectively).

Conclusion

The results of this study suggest that a decrease in claudin-3 could be a sensitive indicator of reflux laryngitis in rats.     

Analysis of gene expression profiles in tympanic membrane following perforation using PCR Array in rats—Preliminary investigation

Objectives

The goal of this work was to identify genes, known to be involved in the skin wound healing, that express differentially in the healthy and injured tympanic membrane (TM), and designate the molecules potentially beneficial for treatment of TM perforation. The molecular mechanisms controlling the course of TM regeneration are far from being elucidated.

Methods

Twenty rats had their tympanic membranes perforated, while four served as a control. Animals were sacrificed on either days 1, 2, 3, 5 and 10 post injury, and TMs were immediately dissected and frozen in liquid nitrogen. Total TM RNA was isolated and reversely transcribed. qPCR was performed using Rat Wound Healing RT² Profiler PCR Array (QIAGEN) containing primers for 84 genes.

Results

Statistically significant changes in the expression of 42 genes were found in various stages of TM healing. The increased expression of genes taking part in the inflammatory reaction (interleukin 6, granulocyte and macrophage chemotactic proteins) was observed from day 2. The expression of several genes of extracellular matrix components and their remodeling enzymes was also changed. Among growth factor genes: Vegfa, Igf1 and Hbegf showed increased expression at the beginning of the healing process, while Hgf expression was highest on day 3.

Conclusions

Several changes in the expression of genes involved in remodeling of extracellular matrix point to important role of connective tissue in TM healing. The molecules accelerating this process, like HbEGF and HGF, seem to be good candidates for further evaluation of their possible use in clinical treatment.     

Spectrum and frequency of GJB2 mutations causing deafness in the northwest of Iran

Objective

Mutations in GJB2 and GJB6 which comprise DFNB1 locus cause up to half of all cases of the prelingual autosomal recessive non-syndromic hearing loss (ARNSHL) worldwide. This study has intended to assess the spectrum and frequency of GJB2/GJB6 mutations in northwest of Iran.

Methods

508 Patients with presumed ARNSHL were analyzed by applying ARMS-PCR, SSCP, PCR-RFLP and sequencing assays.

Results

Seventy-five (14.7%) different homozygous and eighty-seven (17.1%) different compound heterozygous genotypes were detected in this cohort. Concerning the GJB2 gene, c.35delG was the most prevalent mutation, accounting for 16.4% of the samples. In addition 29 sequence variations other than c.35delG mutation were distinguished in GJB2; namely, delE120, Ins A 290-291, R143Q, V37I, R32H, Y155X, V27I + T123N, F154F, 167delT, 312del14, 299-300delA, T8M, W24X, E114G + V27I, 235delC, R184P, V153I, S139N, A171T, M163V (unknown mutation), G127V, E147X, R127H, 35insG, R143W, V27I, G160S, E114G and IVS1 + 1G > A. Moreover, the IVS1 + 1G > A was accounted as a second common mutation.

Conclusions

Overall, the frequency of GJB2 mutations (≥31%) is in agreement with other white population. These findings highlight the importance of the study of GJB2 gene in the diagnosis to provide early treatment and genetic counseling.     

Comparison of nasal packs with transseptal suturing after nasal septal surgery

Objectives

To investigate the effects of transseptal suturing against two different types of nasal packs with respect to pain, operative time and postoperative complications following nasal septal surgery.

Patients and methods

One hundred and fifty patients (aged 18–61 years) scheduled for nasal septal surgery were included. Following surgery, three types of nasal packing systems were utilized: (1) transseptal suturing (Group A: 50 patients); (2) internal nasal splint (Group B: 50 patients); (3) a Merocel standard 8-cm nasal dressing without airway (Group C: 50 patients) to the patients. Postoperative pain, operation time, septal perforation and synechiae formation were evaluated.

Results

The difference between mean operative time of groups B and C was not statistically significant (p > 0.05). The difference between operative time of the two groups against group A was statistically significant (p < 0.05). The mean postoperative pain scores were 2.8 ± 1.2 (median 2) in group A, 6.1 ± 1.3 (median 6) in group B, and 7.3 ± 1.2 (median 7) in group C 1 h to 48 h post-surgery. Merocel and internal nasal splint tampons were found to be significantly more painful than transseptal suturing during 48 h (p < 0.05). There was no statistically significant difference in terms of infection, hematoma, synechiae formation or perforation between the groups (p > 0.05).

Conclusion

The use of transseptal suturing technique is a useful alternative to packing, with only minor increase in operating time.