GJB2 gene mutations causing familial hereditary deafness in Turkey

Mutations in Connexin 26 (Cx26) play an important role in autosomal non-syndromic hereditary hearing loss. In this study, our objective was to find out the significance of Cx26 mutations in Turkish families who had hereditary deafness. Fourteen families who had at least two prelingually deaf children per family were included in the study. One affected child from each of the 14 families was selected for single-stranded conformational polymorphism SSCP analysis. Three PCR reactions were used for each subject to amplify the entire Cx26 coding region with overlap. PCR products were sequenced on an Applied Biosystems (ABI) model 3700 automated sequencer. Six of the 14 representative family members (42.9%) demonstrated shifts on SSCP and were subsequently sequenced for Exons 1 and 2 of GJB2 and were tested for the 432 kb upstream deletion. No mutations were found in Exon 1 and no 432 kb deletions were noted. Three different GJB2 mutations were found in Exon 2 of the probands, which were 35delG, 299-300delAT, and 487G > A (M163V). GJB2 mutations were detected in 21.4% of the families. Two patients were homozygous for 35delG and 299-300delAT mutations, and were given a diagnosis of DFNB1 deafness (14.3%). Two different polymorphisms, 457G > A (V153I) and 380G > AG (R127H) were also found. In conclusion, although GJB2 mutations were detected in 21.4% of the families tested, only 14.3% of subject representatives were homozygous and therefore deafness caused by Cx26 mutation segregated with DFNB1. Thus, contribution of GJB2 mutations appears less significant in familial deafness. This necessitates further assessment for the other known gene regions as well as a search for new genetic factors in familial type of genetic deafness.     

Inflammatory myofibroblastic tumor (inflammatory pseudotumor) of the maxillary sinus mimicking malignancy: a case report of an unusual location (is that a true neoplasm?)

The inflammatory myofibroblastic tumor (IMT) is a space-occupying lesion of unknown etiology and a distinctive but controversial lesion. This type of tumor is recently considered neoplastic rather than inflammatory. It is usually occurring during childhood, composed of fascicles of bland myofibroblastic cells admixed with a prominent inflammatory infiltrate consisting of lymphocytes, plasma cells, and eosinophils. IMT of the maxilla is very rare. The diagnosis of IMT can be made on the basis of histopathology and immunohistoche-mistry. Herein, we presented a patient who had IMT of the maxillary sinus that was initially misinterpreted as a malignant neoplasm upon clinical and radiographic examinations. We discussed the diagnostic and therapeutic procedures and may consider it a true neoplasm.     

Polycythemia vera in a 12-year-old girl: a case report

A case of a 12-year-old girl presenting with headache and splenomegaly and fulfilling the diagnostic criteria of polycythemia vera is reported. Her peripheral blood values were as follows: hemoglobin 18 g/dL, red blood cells 7,000,000/mm 3 , white blood cells 22,000/mm 3 , and platelets 1,248,000/mm 3 . Phlebotomy was performed initially but was ineffective. Afterward 100 mg/kg per day aspirin and 30/mg/kg per day hydroxyurea were given. The patient has been asypmtomatic for 1 year and her recent hemoglobin level is 15.5 g/dL, platelet count 922,000/mm 3 , and white blood cell 12,800/mm 3 . Polycythemia vera is an extremely uncommon disease in childhood and for this reason its treatment is not well established.     

Inhibition of bacterial growth by lignocaine in propofol emulsion

Contamination of propofol, in an emulsion formulation, has been associated with infective complications. Local anaesthetics,some of which are known to have antibacterial properties, are frequently added to the solution to reduce pain on injection. We examined the growth rates of E. coli, S. aureus, S. epidermidis and P. aeruginosa in propofol with and without lignocaine 0.1%-2% after incubation for 2, 5 and 24 hours at 37 degrees C. Growth of microorganisms in each solution was compared by counting the number of colony forming units (CFU). Propofol supported the growth of all microorganisms. An increase in the number of CFUs was observed in all drug combinations 2, 5 and 24 hours after inoculation except for S. aureus (P<0.05). No difference was found in CFU numbers between 2 and 5 hours for this microorganism. With E. coli, a significant decline in colony counts was observed in mixtures of 1% and 2% lignocaine (P<0.05). With the other microorganisms only 2% lignocaine showed a significant reduction in the number of CFUs (P<0.05). We conclude that lignocaine in recommended clinical doses (0.05%-0.1%) did not exhibit adequate antibacterial activity to prevent infective complications.     

Acute alterations in muscle flap microcirculation during tumor necrosis factor alpha-induced inflammation

In reconstructive microsurgery of free tissue transfer, ischemia-reperfusion (IR) injury is an unavoidable component of the procedure, which can affect free flap survival markedly. A notable amount of evidence implicates neutrophils in IR injury. Transforming necrosis factor alpha (TNF-alpha) is known to have a central role as a mediator of neutrophil activation in IR injury. The effect of inflammatory stimuli, TNF-alpha, on flow hemodynamics and leukocyte-endothelial interactions in the muscle flaps submitted to IR injury was investigated. In group 1, 6 rats were administered 1 ml of vehicle solution. In group II rats (N = 6), 1 ml of recombinant human TNF-alpha (10 ng per milliliter) was injected intra-arterially. After an hour of ischemia, the cremaster muscle flaps were monitored at 1-hour intervals during 6 hours of reperfusion. After clamp removal, the number of rolling, adhering, and transmigrating leukocytes in the TNF-alpha group was increased by 4-fold, 3-fold, and 3.5-fold respectively compared with the control group (p < 0.05). The increase in rolling leukocytes continued for as long as 3 more hours, whereas the number of adhering and transmigrating leukocytes remained high throughout the experiment. A significant increase in the diameters of the third- and fourth-order arterioles in the TNF-a group was accompanied by a decrease in the number of flowing capillaries at all intervals (p < 0.05). The effect of TNF-alpha-induced inflammation on leukocyte activation was found to be maximal during the first 3 hours of reperfusion. The vasodilatory effect of TNF-alpha was observed only on the third- and fourth-order arterioles.     

Combination of anti-ICAM-1 and anti-LFA-1 monoclonal antibody therapy prolongs allograft survival in rat hind-limb transplants

Immunosuppressive effects of monoclonal antibodies against adhesion molecules were validated in solid organ transplants. There have been only a few reports on the effect of these antibodies on limb transplantation. In this study, the authors investigated the effects of anti-ICAM-1 and anti-LFA-1 therapy in the rat hind-limb-cremaster transplantation model. Twenty transplantations were performed across a major histocompatibility barrier between Lewis Brown Norway (LBN, RT-1(l+n)) and Lewis (LEW, RT-1(l)) rats in four experimental groups of five animals each. Group 1 animals received only vehicle solution; Groups 2 and 3 received monoclonal antibodies against ICAM-1 and LFA-1, respectively; Group 4 received a combination dose. Treatments were continued for 7 days. Clinical signs of rejection were noted daily, and correlated with in vivo microcirculatory measurements. The activation of adhering leukocytes was significantly lower in rats treated with anti-ICAM-1, anti-LFA-1, and combination than in controls (p < 0.05). Transmigrating leukocytes were also reduced in antibody-treated groups, when compared to the control group (p < 0.05). The mean number of rolling lymphocytes was significantly reduced only in the combination group (p < 0.05). Endothelial edema index, a measure of endothelial swelling, was lowest in the combination group (p < 0.05). The first clinical signs of rejection were noted between the 5(th) and 9(th) days in the control group, on the 9(th) day in the anti-ICAM-1 or anti-LFA-1 groups, and on the 13(th) day with combination therapy. Monoclonal antibodies against LFA-1 or ICAM-1 alone inhibit the activation of leukocytes at the microcirculatory level but do not prolong graft survival. However, the combination of anti-ICAM-1 and anti-LFA-1 monoclonal antibodies significantly prolonged allograft survival in this composite tissue transplantation model.     

Exercise-induced ventricular tachycardia in children

Two children with exercise-induced tachycardia, one with idiopathic long-QT syndrome, are presented. The patients were evaluated by exercise testing and electrophysiologic study. From the onset of treatment with the beta-blocking agent, pindolol, the patients have been symptom-free. These findings emphasize that children with syncope must be evaluated by ECG, exercise testing, 24-h Holter-monitoring, and finally, electrophysiological study.