Kubilay Metin

Elevated expression of MMP-13 and TIMP-1 in head and neck squamous cell carcinomas may reflect increased tumor invasiveness

BackgroundMatrix metalloproteinases [MMPs], which degrade the extracellular matrix, play an important role in the invasion and metastasis of squamous cell carcinomas. One MMP, MMP-13, is thought to play a central role in MMP activation. The purpose of this study was to investigate MMP-13 and TIMP-1 expression in squamous cell carcinomas of the head and neck and to relate these levels of expression to histologic patterns of invasion.MethodsThis study included T1 lesions obtained via biopsy from the larynx, tongue, and skin/mucosa of 78 patients with head and neck squamous cell carcinomas. The relationship between expression of MMP-13 and TIMP-1 and the mode of tumor invasion [MI] was evaluated immunohistochemically, using breast carcinoma tissue as a positive control.ResultsIncreased expression was observed in highly invasive tumors, as reflected by the significant correlation between the degree of staining for MMP-13 or TIMP-1 and MI grade [p < 0.05]. There was no significant relationship between the degree of staining for MMP-13 or TIMP-1 and patient age, sex, tumor site, or tumor histologic grade. In addition, levels of staining for MMP-13 did not correlate with levels of staining for TIMP-1.ConclusionThe expression of MMP-13 and TIMP-1 appears to play an important role in determining the invasive capacity of squamous cell carcinomas of the head and neck. Whereas additional studies are needed to confirm these findings, evaluating expression of these MMPs in small biopsy samples may be useful in determining the invasive capacity of these tumors at an earlier stage.

Intramuscular hemangioma of the masseter muscle.

Abstract Intramuscular hemangiomas (IMH) are uncommon tumors of the head and neck, but often occur in the trunk and extremities. When present in the head, the masseter muscle is the most frequently involved site, although constituting only 0.8% of all hemangiomas. Accurate preoperative diagnosis is uncommon without cytology or biopsy. A case of IMH of the masseter muscle in a 24-year-old Turkish woman is presented. Clinical, radiologic and histologic findings and treatment modalities are reviewed.

Surgical approaches to antrochoanal polyps in children

Antrochoanal polyps (ACP) represent 4-6% of all nasal polyps in the general population, but this proportion increases to 33% in the pediatric group. The aim of this study is to discuss clinical and radiological findings, and some different surgical approaches with their results in the pediatric patients. This study consists of eight children with ACP diagnosed by means of clinical examination, nasal endoscopy and computed tomography. One patient was treated only with simple polypectomy. In five patients, transcanine sinuscopy (TS) was added to functional endoscopic sinus surgery. Four of the patients underwent anterior ethmoidectomy and uncinectomy. Middle meatal antrostomy was applied to two of them. No recurrence was encountered within 5-30 months. The decision for the appropriate type of surgery for ACP is influenced by factors such as patients age, other accompanying sinus pathologies, recurrence after previous surgery, and the possibility of total excision. In patients carrying the risk of recurrence, it is especially important to remove the polyp completely and manage other sinus pathologies, as well as avoiding an unnecessarily expanded operation. In selected patients, we believe that TS may be adequate in totally removing ACP.

Sensorineural hearing loss associated with otitis media with effusion in children

Sensorineural hearing loss (SNHL) is known to occur in various types of otitis media. Although the mechanism by which SNHL develops in association with otitis media with effusion (OME) is unknown, several hypotheses have been advocated up to now. We reviewed the clinical records of children with otitis media with effusion (OME) to reveal the association with sensorineural hearing loss. The material consisted of 71 children (119 ears) who were diagnosed as having OME and gave reliable audiograms in our clinic during an 11 month period from February 1997 through January 1998. From these cases those which showed bone conduction loss of 25 dB or higher at any one of the frequencies of 250 through 4 kHz were selected and considered to be cases of SNHL. Eight cases (9%) which had temporary threshold shift (TTS) or permanent threshold shift (PTS) were considered to be etiologically related to OME. The clinical course in each of these cases with SNHL was reviewed and evaluated in detail. We noted that all children with TTS improved completely. The result of this study indicates that we have to be aware of a possible development of SNHL during the course of OME.

The new anatomical viewpoint of the nose: the interdomal fat pad.

AbstractTo the plastic surgeon, the nose is one of the most interestingand challengingfacial structures and its anatomy is well defined. From the point of view of aesthetic surgery, the nasal tip area is an especially important structural unit, and the most di.cult to address in rhinoplasty. The objective of this study was to demonstrate the existence of the nasal interdomal fat pad as a distinct anatomical structure that occupies the interdomal space and is apart from subcutaneous fat. In our study we proved the existence of the interdomal fat pad by histochemical studies and anatomical observations in 88 patients who underwent primary external rhinoplasty and three fresh cadavers. All specimens were examined by hemotoxylen-eosin, Sudan black, and oil red staining, as well as S100 protein immunoreactivity staining. The mass of the interdomal fat pad was greater in patients with bulbous noses and/or divergent alar cartilage than in patients with thin skin. We speculated that the interdomal fat pad may be the major anatomic structure contributingto unexpected results in difficult cases, such as those involvingbulbous noses. According to our study, the existence of the interdomal fat pad should be kept in mind duringthe preoperative planning of rhinoplasty.

Effects of Constant Lightness, Darkness and Parachlorophenylalanine Treatment on Tail Regeneration in the Lizard Ophisops elegans macrodactylus: Macroscopic, Biochemical and Histological Changes

A better understanding of regenerative growth is very important for the development of new potential strategies. Recently, the pineal secretory product melatonin was shown to stimulate the regeneration process. In this study, we carried out an experimental investigation of tail regeneration in young adult lizards, Ophisops elegans macrodactylus Berthold, 1842, addressing the role of melatonin on the regeneration process. Lizards were divided into three groups: constant light‐exposed control group (n = 13), constant dark‐exposed group (n = 15) and parachlorophenylalanine (p‐CPA) treatment group exposed to constant light (n = 15). Using a tail autotomy procedure, the effects of p‐CPA treatment on connective tissue together with neural tissue and vascular tissue in regenerating tail in lizards were investigated. p‐CPA (400 μg/kg body mass) was injected from day 0 to 30 days after autotomy. p‐CPA treatment produced a significant increase in the length of the regenerated tail compared with light‐exposed control and dark‐exposed lizards. Total collagen content was found to be higher in p‐CPA‐treated animals in comparison with other groups. Histologically, a higher percentage of connective tissue and vascular tissue and a lower percentage of neural tissue were found in the regenerated tails of the p‐CPA‐treated lizards. Importantly, the percentage of neural tissue in lizards in the dark‐exposed animals was higher than that in animals of both light‐exposed and p‐CPA treatment groups. Thus, it is clear that p‐CPA has a stimulatory influence on fibroblast collagen production and vascularization of the regenerated tail in the lizards. Furthermore, it seems that the neural regeneration process was markedly enhanced in lizards exposed to continuous darkness. Based on the results of our study, it is suggested that melatonin may be an active factor that speeds up the rate of tail regeneration in lacertilians.

Purification and Characterization of an Alkali-Thermostable Lipase from Thermophilic Anoxybacillus flavithermus HBB 134.

An intracellular lipase from Anoxybacillus flavithermus HBB 134 was purified to 7.4-fold. The molecular mass of the enzyme was found to be about 64 kDa. The maximum activity of the enzyme was at pH 9.0 and 50°C. The enzyme was stable between pH 6.0 and 11.0 at 25°C, 40°C, and 50°C for 24 h. The Km and Vmax of the enzyme for pNPL substrate were determined as 0.084 mM and 500 U/mg, respectively. Glycerol, sorbitol, and mannitol enhanced the enzyme thermostability. The enzyme was found to be highly stable against acetone, ethyl acetate, and diethyl ether. The presence of PMSF, NBS, DTT and β-mercaptoethanol inhibited the enzyme activity. Hg(2+), Fe(3+), Pb(2+), Al(3+), and Zn(2+) strongly inhibited the enzyme whereas Li(+), Na(+), K(+), and NH4(+) slightly activated it. At least 60% of the enzyme activity and stability were retained against sodium deoxycholate, sodium taurocholate, n-octyl-β-D-glucopyranoside, and CHAPS. The presence of 1% Triton X-100 caused about 34% increase in the enzyme activity. The enzyme is thought to be a true lipase since it has preferred the long-chain triacylglycerols. The lipase of HBB 134 cleaved triolein at the 1- or 3-position.

Cervicopectoral flap in head and neck cancer surgery.

BackgroundReconstruction of the head and neck after adequate resection of primary tumor and neck dissection is a challenge. It should be performed at one sitting in advanced tumors. Defects caused by the resection should be closed with flaps which match in color, texture and hair bearing characteristics with the face. Cervicopectoral flap is a one such flap from chest and neck skin mainly used to cover the cheek defects.MethodsThis study included twelve patients presenting with cancer of the head and neck to Izmir Ataturk Training Hospital and Adnan Menderes University Hospital. Tumor resection and neck dissection was performed in one session by the same surgeon. A single incision was made and a medially based cervicopectoral fascio-cutaneous flap was used for surgical exposure in neck dissection and for closure of defects after tumor resection.ResultsThere was no major complication. Two flaps had partial superficial epidermolysis at the suture line. Good aesthetic and functional results were achieved.ConclusionThe cervicopectoral flap is an excellent alternative for the reconstruction of head and neck. Harvesting and application of the flap is rapid and safe. Only a single incision is sufficient for dissection and flap elevation. This flap achieves perfect surgical exposure, makes neck dissection easy and allows one to perform both tumor resection and neck dissection in one session.

Effects of capsaicin pre-treatment in experimentally-induced secretory otitis media

Neurogenic inflammation may play a role in the aetiology of secretory otitis media (SOM). The strongest candidate that initiates the characteristic symptoms of neurogenic inflammation is supposed to be substance P. Capsaicin is a specific antagonist of substance P. The effects of capsaicin on middle ear mucosa have not been studied yet. In an attempt to investigate the effect of pre-treatment with capsaicin on the development of SOM an experimental study was performed. Fourteen Wistar rats were divided into two groups. Seven rats were pre-treated with capsaicin (Group 1) and the others were administered isotonic saline solution (Group 2). Seven days after the third injection rats were operated on and the right tympanal orifice of the Eustachian tube was obstructed. Animals were sacrificed seven days after the operation. Their bullas were excised bilaterally and were studied by light microscopic technique. In Group 1 there was no effusion except for one case. The subepithelial layer was thickened by fibroblast proliferation. Capillary proliferation and some glandular atrophy were observed. In Group 2 the middle ear lumens were filled with effusion. Oedema with dilatation in capillaries and medium-sized vessels of lamina propria was observed as a common feature of the group. Subepithelial fibrosis was found in one case. Capsaicin pre-treatment prevented the formation of effusion in the middle ear lumen in spite of tuba occlusion. The results of this preliminary study lead us to consider that an imbalance in the autonomic innervation of the mucosa of the middle ear may play a role in the aetiology of SOM as in vasomotor rhinitis, and capsaicin may be an alternative in the treatment.

Effects of Ca2+ channel blocker verapamil on tissue regeneration in a lizard tail autotomy model: a biochemical and histological study

Ca2+ ions have been reported to augment the activities of many cell types including cellular proliferation and tissue regeneration. Moreover, it is well known that verapamil is a L-type voltage-gated Ca2+ antagonist with important clinical implications. To evaluate the role of Ca2+ ions in the regeneration of tail in lizards, verapamil was used in vivo to modulate the activity of intracellular Ca2+ in a lizard tail autotomy model. A total of 35 adult lizards were divided into three groups: lightness control group ( n = 11), darkness group ( n = 11) and verapamil treatment group ( n = 13). The tails of adult lizards were amputated by pinching off the tail at the 15 th segment from the vent to induce tail regeneration. The first two groups served as untreated constant lightness and darkness groups as controls, but the remaining group received intraperitoneally 1 mg/kg of verapamil. Following autotomy, the length of regenerating tails was measured at 10, 15, 20, 25, and 30 days post-amputation. At the end of the study, the regenerating tails from animals from each group were removed for collagen assay procedure and histological examination. We found that verapamil produced a reduction in the length of the regenerated tail compared to untreated lightness group and the percentage of tail replaced in verapamil treatment group was lower than those in lightness control group. Total collagen contents were found to be higher in lightness control group in comparison with darkness and verapamil treatment groups. Accordingly, a quantitative stereological evaluation showed a higher percentage of neural tissue and a lower percentage of connective tissue, as well as vascular tissue, in the cross-sections of the regenerated tails taken from Ca2+ channel blocker verapamil-treated lizards, as compared to other groups. In conclusion, our results suggest that verapamil influences a variety of processes including fibroblast collagen production, neurogenesis, and angiogenesis during tail regeneration in lizard, possibly due to inhibition of intracellular Ca2+ ion by verapamil.