Telomerase activity in prognostic histopathologic features of melanoma.

BACKGROUND: Telomerase activity (TA) is believed to play a role in the regulation of senescence and to limit the number of cell divisions. The deregulation of telomerase appears to contribute to oncogenesis and the formation of immortal cell lines. As a result, it is believed that it could be used as a prognostic marker in melanoma. METHODS: TA was assayed by the polymerase chain reaction PCR-ELISA-based telomeric repeat amplification protocol (TRAP assay). One hundred and eight samples were distributed in four histological groups: 30 samples from primary cutaneous melanomas, 24 from peritumoural skin sites, 28 from benign melanocytic lesions, and 26 from normal skin sites as a control. RESULTS: TA was different among the four tested groups (Kruskall-Wallis test p<0.001), and increasing values of TA were observed progressing from normal skin to benign and then to malignant lesions. Among melanoma samples, there was a significant association between TA and ulceration (p=0.025), TA and vascular invasion (p=0.018) and TA and mitotic rate (p=0.029) (Mann-Whitney test). A linear regression analysis showed significant associations between the increase of TA with Breslow thickness (p=0.004) and the presence of satellites (p=0.002). CONCLUSIONS: We observed that TA had increased from control skin to peritumoural skin, and then to benign melanocytic lesions and finally to melanoma, suggesting tumour progression. TA showed higher values in the presence of some important histopathologic parameters related to poor prognosis in cutaneous melanoma such as ulceration, vascular invasion, satellites, high rates of mitosis, and in thicker tumours.     

Relations of the pterygoid hamulus and hard palate in children and adults: anatomical implications for the function of the soft palate.

We investigated spatial relations of the pterygoid hamuli to the hard palate on 65 skull bases: 31 disarticulated sphenoidal bones from the newborn up to 9 years of age, 19 skulls of adult skeletons (21-59 age group), and 15 skulls aged 60-100 years. We measured: (a) width of the hard palate in the choanal region, (b) length of the hamulus, (c) inclination of the hamulus from the perpendicular line, and (d) distance between the tips of the contralateral hamuli. The width of the hard palate in the choanal region was smallest in children (mean +/- standard deviation, 21.5 +/- 2.6 mm) compared with adult skulls (26.8 +/- 2.3 mm in the 21-59 age group and 25.4 +/- 1.9 mm in the 60-100 age group; P<0.05, one-way analysis of variance (ANOVA) and Student-Newman-Keuls post hoc test). Children had the shortest hamulus (3.6 +/- 1.5mm), and its length increased in the adult age group to 6.9+1.7mm (P<0.05), and then again decreased to 5.0 +/- 1.9 mm in the 60-100 age group (P<0.05 vs. adults and children). The distance between the tips of the contralateral hamuli and their lateral inclination from the perpendicular plane were also greater in the adult age group (38.0 +/- 2.7mm and 35.9 +/- 13.7 degrees, respectively) than either in children (31.0 +/- 3.7mm and 19.6 +/- 12.1 degrees) or the elderly (32.7 +/- 3.9mm and 19.7 +/- 10.3 degrees) (P<0.05). Our study showed that the anatomical measures of the pterygoid hamulus and its relation to the surrounding structures change with age, and occur with the changes in the function of pharyngeal and palatal muscles in deglutition. These changes may have clinical relevance for sleep apnoea and snoring.     

Poststroke DNA immunization against neurite growth inhibitors is beneficial to the recovery from local cerebral ischemia in rats

BACKGROUND： Inhibitory signals, i.e. neurite growth inhibitors （NGIs）, presenting on central nervous system （CNS） myelin have been shown to play a crucial role in inhibiting lesioned axonal sprouting and leading to less functional recovery. Vaccines targeting NGIs may provide multifactorial protection against brain insults by overcoming the inhibitory effects of these NGIs and boosting the body＇s immune repair mechanisms. OBJECTIVE： To evaluate the effect of poststroke DNA immunization against NGIs on the rehabilitation for sensorimotor function of rat models of local cerebral ischemia. DESIGN： Completely randomized grouping design, and controlled experiment. SETTING： Brain Injury Research Laboratory, Department of Neurosurgery, National Neuroscience Institute, Singapore. MATERIALS： Sixty adult male Sprague-Dawley rats ranging in age from 45 to 120 days and in weight from 180 to 250 grams were provided by Animal Center of Department of Anatomy, Faculty of Medicine, National University of Singapore. pcDNA3.1（＋）-neurite growth inhibitors （pcDNA-NGIs） a gift was provided by Dr. Xiao from Department of Clinical Research, Singapore General Hospital, Singapore. METHODS： The experiment was carried out at Brain Injury Research Laboratory, Department of Neurosurgery, National Neuroscience Institute, Singapore from August 2003 to April 2005. （1）The involved rats were randomized into 3 groups： pcDNA-NGIs group （group A）, pcDNA3.1 （＋） group （group B） and model group （group C）, with 20 rats in each group. Left focal cerebral ischemia （FCI） was permanently induced through middle cerebral artery occlusion （MCAO） with the assistance of an operating microscope. Successful MCAO was determined by a 20% decrease to baseline in the ipsilateral cerebral blood flow. 100 μg of pcDNA-NGIs eluted in phosphate-buffered saline （PBS） was intramuscularly injected into the tibial muscle once a week after MCAO for 6 weeks in group A. As control, pcDNA3.1 （＋） was also administrated in the same way in group B and nothing was administrated in group C. （2） The modified neurological severity score （mNSS）, a composite of motor, sensory, reflex and balance tests, was used to test the sensorimotor deficit. The mNSS was graded on a scale of 0 - 18, i.e. normal score was 0, maximal deficit score was 18, and 1 point was warded for the inability to perform the tasks or the lack of a tested reflex. （3） The newly generated axons of corticorubral projection were traced by stereotaxic guided injection of 100 g/L biotinylated dextran amine. Rats were sacrificed two weeks after tracing, and cryostat coronal sections of midbrains （30μm） were reacted to BDA according to the manufacturer＇s instruction by the free-floating method. Images were captured on a DM RXA2 LEICA Microscope with a Spot Digital Camera system （Germany）, and the numbers of labeled axons on the denervated side in four standard coronal sections including the red nucleus were manually quantified. MAIN OUTCOME MEASURES： （1） The number of newly generated axons of corticorubral projection. （2）The improvement in sensorimotor deficit. RESULTS： All the involved 60 rats entered the stage of final analysis. （1） The number of newly generated axons of corticorubral projection of rats： Only ipsilateral axons of CRP were noted with little evidence of fibers crossing to the contralateral red nucleus in rats of groups B and C. More BDA-positive fibers crossing the midline and terminating in the contralateral red nucleus in appropriate target areas mirroring the non-differentiated red nucleus were found in rats of group A. Quantitative analysis showed that BDA-labeled axons in the denervated side of rats in group A were more than those in group B （P 〈 0.05）. （2） Improvement in sensorimotor deficit of rats： At 2 weeks after immunization, significant improvement in sensorimotor deficit was found in rats of group A. There were significant differences of improvement in sensorimotor deficit of rats between group A and group B or group C at 12 and 14 weeks after immunization （P 〈 0.05）. CONCLUSION： （1） Poststroke DNA immunization against NGIs leads to increased sensorimotor recovery following FCI and compensatory newly growth of axons from corticorubral projection.     

Development and proliferation of lymphocytes in mice deficient for both interleukins-2 and -4

Interleukin (IL)-2 and IL-4 are considered as important regulators of growth and differentiation of lymphocytes. We report that in mice made deficient for both IL-2 and IL-4 by gene targeting all major T cell subsets and B cells were normal, indicating that IL-2 and IL-4 are not essential for development of the immune system. Paradoxically, proliferation of T cells was increased in both IL-2- and IL-4-deficient homozygous mice.     

Role of endotracheal stenting in tracheal reconstruction surgery—retrospective analysis

Objective: To review a single institution experience with tracheal stenosis treatment and to define a role of endotracheal stenting in tracheal reconstruction surgery. Patients and methods: In the period between January 1991 and January 2003, 163 patients underwent tracheal reconstruction. There were 114 males and 49 females in age range from 0.5 to 79 years (mean 43.2 years). Indications for reconstruction were: posttracheostomic (PostTS) and postintubation (PostINT) stenoses in 111 cases, tumor-stenosis in 24 cases, tracheo-esophageal fistulas (T-Efist) in 17 cases, traumatic laesions in six and functional stenosis in five cases. For these indications, the following procedures were performed: segmental tracheal resection in 87 cases, stenting in 68 cases (by our own modification of Montgomery T-tube in 65 cases and by other traditional endo-stents in three cases). Primary suture of traumatic tracheal wall was performed in five cases. Three cases involved laser intervention and tumor resections, respectively. Results: Segmental tracheal resection (n=87) was successful in almost all the cases (96%). T-tube was applied in 65 cases; the indications included: PostTS and PostINT stenoses in 38 cases, tumors in 17 cases, T-E fistulas in seven cases and functional stenosis in three cases. Twenty-seven patients (41.6%) were successfully treated by this modality. In 19 patients (29.2%), the stenting is still continuing, but they are candidates for extraction of the T-tube in near future. In 19 patients (29.2%) with malignant stenoses, the T-tube was applied only as a palliation. All these patients died due to their underlying malignant disease; the follow-up ranged from 2 to 18 months. Conclusion: Tracheal stenosis is a serious, life-threatening disease with increasing incidence. In our study, the best results were achieved by segmental tracheal resection. However, the endotracheal stenting is the method of choice, when the segmental resection cannot be performed. The management of tracheal stenosis reconstruction by our own modification of Montgomery T-tube is being presented.     

Total replacement of bladder and urethra by cecum and appendix in bladder exstrophy

The first case of total bladder and urethral replacement by cecoappendiceal unit was achieved in a five-year-old boy born with bladder exstrophy. Residual vesical and prostatic tissue was utilized to provide continence successfully.