Effect of Celecoxib on Ca2+Fluxes and Proliferation in MDCK Renal Tubular Cells

The effect of celecoxib on renal tubular cells is largely unexplored. In Madin Darby canine kidney (MDCK) cells, the effect of celecoxib on intracellular CaCa2+ concentration ([Ca2+]i) and proliferation was examined by using the Ca(2 +)-sensitive fluorescent dye fura-2 and the viability detecting fluorescent dye tetrazolium, respectively. Celecoxib (> or =1 micro M) caused an increase of [CaCa2+]i in a concentration-dependent manner. Celecoxib-induced [CaCa2+]i increase was partly reduced by removal of extracellular CaCa2+. Celecoxib-induced CaCa2+ influx was independently suggested by MnCa2+ influx-induced fura-2 fluorescence quench. In Ca(2 +)-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca(2 +)-ATPase, caused a monophasic [CaCa2+]i increase, after which celecoxib only induced a tiny [CaCa2+]i increase; conversely, pretreatment with celecoxib completely inhibited thapsigargin-induced [CaCa2+]i increases. U73122, an inhibitor of phospholipase C, abolished ATP (but not celecoxib)-induced [CaCa2+]i increases. Overnight incubation with 1 or 10 micro M celecoxib decreased cell viability by 80% and 100%, respectively. These data indicate that celecoxib evokes a [CaCa2+]i increase in renal tubular cells by stimulating both extracellular CaCa2+ influx and intracellular CaCa2+ release and is highly toxic to renal tubular cells in vitro.

Surface ultrastructure and mechanical property of human chondrocyte revealed by atomic force microscopy

OBJECTIVE

The mechanical properties of chondrocytes influence maintenance of the articular cartilage extracellular matrix. To differentiate the mechanical properties of chondrocytes between a young, normal modulus and an old, osteoarthritic (OA) modulus, we used an atomic force microscope (AFM) to probe the surface ultrastructure and to measure their adhesion force and stiffness.

METHODS

We directly visualized a single chondrocyte cell by using AFM and quantitatively measured the dimensions of the cells.

RESULTS

Profiles displayed heights of 1026+/-203 and 1668+/-352 nm for old and young cells, respectively. Contour maps revealed differences in the sizes and structures of the two groups. Mean calculated adhesion forces differed between normal and OA chondrocytes (7.06+/-3.35 and 2.97+/-1.82 nN, respectively), as did calculated stiffness values (0.0960+/-0.009 and 0.0347+/-0.005 N/m, respectively).

CONCLUSION

These findings suggested that the mechanical properties of normal chondrocytes substantially differed from those of OA chondrocytes. We believe this study represents the first direct characterization of the surface ultrastructure and mechanical measurements of human chondrocytes between normal and OA stages. This new approach could be a useful technique for investigating age-related changes in the properties of human chondrocytes.

Deleterious effects of MRI on chondrocytes

OBJECTIVE

To assess how magnetic fields (MFs), with or without concurrent radio frequency (RF), influence chondrocytes and knee joint repair, we applied an MF strength via magnetic resonance imaging (MRI) slightly greater than the frequently used dosage in the clinics and examined the effects of these treatments in vitro on human chondrocytes and in vivo in pigs.

METHODS

Human chondrocytes were directly exposed to a 3-tesla (T) magnetic field (MF group) or a 3-T static magnetic field plus 125.3 MHz radio frequency (MF+RF group), and cell proliferation, apoptosis, cytosolic Ca2+ ([Ca2+]i) fluxes and expression of the apoptosis-related proteins of the treated cells were examined to assess the effects of the treatments. In the pig study, we examined the effects of the treatments on the recovery of surgically damaged pig knees.

RESULTS

A 3-T static MF and RF suppressed cell growth and induced apoptosis through p53, p21, p27 and Bax protein expression. In the pig model, we found that MRI surveillance had a deleterious effect on the recovery of the damaged knee cartilage.

CONCLUSION

Magnetic strength, with or without concurrent RF, suppressed chondrocyte growth in vitro and affected recovery of damaged knee cartilage in vivo in the pig model. These results may be specific to the parameters used in this study and may not apply to other situations, field strengths, forms of cartilage injury, or animal species.

Characterization of a nematic PALC at large oblique incidence angles

Compared with conventional photometric methods of measuring cell parameters, including the cell gap and the pretilt angle of a nematic parallel-aligned liquid crystal (PALC) using multiple wavelengths at normal incidence, this research proposes the use of a phase-sensitive interferometric ellipsometer to determine cell parameters precisely based on a single wavelength at large oblique incidence angles. The advantage of this method is that it detects the phase difference using an optical heterodyne interferometer in which a common phase noise rejection mode is provided. Thus, there is a high signal-to-noise ratio (SNR) on the phase measurement. In addition, a range of large oblique incidence angles on the PALC is used so that a high sensitivity measurement of the cell parameters is obtained experimentally. During the measurements, the multiple reflections and spatial shifting effect of the emerging extraordinary ray (E-ray) and ordinary ray (O-ray) from the PALC at large oblique incidence angles are able to be reduced effectively by the use of retro-reflected geometry in the interferometer. The experimental results verify that the sensitivities for the cell gap and pretilt angle measurements are 0.3 nm and 0.01 degrees , respectively.

Correlation of plasma leptin and adiponectin with insulin sensitivity and beta-cell function in children - the Taipei Children Heart Study

To investigate the association between plasma leptin and adiponectin and insulin sensitivity in children, 580 school children (294 boys and 286 girls) with mean age of 13.3 years (12-16 years) were randomly selected from the Taipei Children Heart Study. Baseline measurements included body weight, body mass index (BMI), plasma glucose, insulin, proinsulin, leptin and adiponectin levels. Insulin resistance and beta-cell function were assessed using the method of homeostatic model, HOMA-IR and HOMA-beta, respectively. We found that girls had higher levels of plasma leptin, adiponectin and HOMA-beta than boys. There was no significant difference in HOMA-IR between boys and girls. Plasma leptin concentrations were positively correlated with body weight, BMI, insulin and proinsulin concentrations, HOMA-IR and HOMA-beta, whereas plasma adiponectin levels were inversely associated with body weight, BMI and proinsulin levels in both sexes. In girls, adiponectin concentrations were negatively correlated with insulin concentration and HOMA-IR. In multiple regression analyses, plasma leptin was more positively associated with insulin and proinsulin levels, HOMA-IR and HOMA-beta than was adiponectin in boys. This association persisted even after adjusting for body weight, BMI and pubertal status. In conclusion, plasma leptin was more strongly associated with insulin sensitivity and beta-cell function than was adiponectin among children, particularly in boys.

Formulas for determining the dimensions of venous graft required for penile curvature correction

To evaluate the quantity of penile veins for use as patch material for the treatment of penile curvature, we devised two formulas: from the calculus of applied civil engineering and a diagram from the goniometry of the cadavers' penises, respectively, and the techniques for their application. From March 1995 to July 2003, a total of 65 consecutive patients with penile curvature - 41 men with Peyronie's deformity and 24 with congenital penile deviations - underwent grafting with autologous deep dorsal veins with or without cavernosal veins as patch material. The patched veins required were calculated from the formula (pi)r(2)theta/45 degrees , which is derived from calculus. The tunical incision sector was meticulously performed in accordance with our diagram which is interpolated from seven male cadavers via goniometry and consequently the length of patched veins required was 2 (pi)r(theta)(')/theta. The corporotomy defect was fashioned with the detubularized veins after they were adequately prepared and spliced. In these patients, the average available area of the veins was 4.9 x 2.2 cm(2) (range, 4.5 x 1.8 to 5.6 x 2.4), which seemed adequate in all cases for patching, although 11 of them required two patches. Overall, 21 patients required a modified Nesbit's procedure on the contralateral/ipsilateral tunica to attain a satisfactory penile shape. Because of its anatomical vicinity and its availability as material, the deep dorsal vein associated with the cavernosal vein may play an indispensable role in grafting even with local anaesthesia on an outpatient basis.

A high yield robotic synthesis of 9-(4-[18F]-fluoro-3-hydroxymethylbutyl)guanine ([18F]FHBG) and 9-[3-[18F]fluoro-1-hydroxy-2-propoxy)methyl]guanine([18F] FHPG) for gene expression imaging

The aim of this study was to develop an automated synthesis of 9-(4-[(18)F]-fluoro-3-hydroxymethylbutyl)guanine ([(18)F]FHBG) and 9-[(3-[(18)F]fluoro-1-hydroxy-2-propoxy)methyl]guanine ([(18)F]FHPG) using a Scanditronix Anatech RB III robotic system. [(18)F]HF was produced via (18)O(p, n)(18)F using a Scanditronix MC17F cyclotron. On average, a typical run produced [(18)F]FHBG and [(18)F]FHPG with an uncorrected radiochemical yield of 19% and 16%, respectively, at end of synthesis (EOS) from irradiation of 95% enriched [(18)O]water. The total synthesis time was 80 min. The retention time of [(18)F]FHBG and [(18)F]FHPG (the radio-peak) was 3.9 and 4.0 min, respectively, which was consistent with the [(19)F]FHBG and [(19)F]FHPG ultraviolet peak. The radiochemical purity was greater than 97%. A robotic, automated method for [(18)F]FHBG and [(18)F]FHPG radiosynthesis is therefore feasible. The radiation burden for the operator can be reduced as much as possible. Sufficient radioactivities of [(18)F]FHBG and [(18)F]FHPG could be obtained for non-invasive monitoring the expression of transfected gene in vivo with positron emission tomography (PET).

The application of mini-implants for orthodontic anchorage

The aim of this study was to explore the use of mini-implants for skeletal anchorage, and to assess their stability and the causes of failure. Forty-five mini-implants were used in orthodontic treatment. The diameter of the implants was 2mm, and their lengths were 8, 10, 12 and 14mm. The drill procedure was directly through the cortical bone without any incision or flap operation. Two weeks later, a force of 100-200g was applied by an elastometric chain or NiTi coil spring. Risk factors for the failure of mini-implants were examined statistically using the Chi-square or Fisher exact test as applicable. The average placement time of a mini-implant was about 10-15min. Four mini-implants loosened after orthodontic force loading. The overall success rate was 91.1%. The location of the implant was the significant factor related to failure. In conclusion, the mini-implants are easy to insert for skeletal anchorage and could be successful in the control of tooth movement.

A simple model for quantification of the radiobiological effectiveness of the 10B(n,α)7Li capture reaction in BNCT

A simple model has been developed for predicting radiobiological effectiveness of the neutron capture reaction in boron neutron capture therapy. This model was derived from the relationship between the cell survival from the boron capture reaction, the intracellular boron concentration, and the thermal neutron fluence. We found that the cell-killing effect of the boron capture reaction was well described using a power function of the intracellular boron concentration. Hence the relationship between cell survival from the boron capture reaction, intracellular boron concentration, and the thermal neutron fluence could be determined using a simple mathematical equation. We consider that our current approach is more appropriate and realistic than the conventional theoretical mathematical model used to estimate the radiobiological effectiveness of the neutron capture reaction in boron neutron capture therapy.

Sibutramine improves insulin sensitivity without alteration of serum adiponectin in obese subjects with Type 2 diabetes

AIM

To evaluate the effect of sibutramine on weight loss, insulin sensitivity and serum adiponectin levels in obese patients with Type 2 diabetes.

METHODS

This study is a randomized, double-blind, placebo-controlled parallel comparison study of sibutramine 15 mg/day and placebo. Forty-eight eligible obese patients with Type 2 diabetes (age between 30 and 75 years with body mass index > or = 27 kg/m(2)) were randomly assigned to receive either placebo (n = 24) or sibutramine (15 mg/day) (n = 24) for 6 months. Fifteen subjects in each group underwent meal tests and modified insulin suppression tests before and after 6 months' treatment.

RESULTS

After 6 months of sibutramine treatment statistically significant changes from baseline were observed for body weight (85.4 +/- 2.5 vs. 82.9 +/- 2.4 kg, P < 0.005) and body mass index (32.0 +/- 0.7 vs. 31.4 +/- 0.6 kg/m(2), P < 0.05) without a significant alteration of waist-hip ratio (W/H), blood pressure, heart rate, glycaemic parameters or lipid profiles. The steady-state plasma glucose (SSPG) level during the modified insulin suppression test was significantly reduced in the sibutramine group (17.33 +/- 2.92 vs. 14.29 +/- 4.19 mmol/l, P < 0.05) despite similar steady-state plasma insulin (SSPI) concentrations. In addition, serum adiponectin and C-reactive protein (CRP) levels remained unchanged, although modest weight reduction was achieved after sibutramine treatment. There were also no significant correlations between changes in serum adiponectin and reduction of SSPG or body weight. Daily ambient plasma insulin and glucose concentrations in response to a test meal were not significantly different in subjects receiving sibutramine treatment.

CONCLUSIONS

We conclude that treatment with sibutramine 15 mg once daily effectively reduces weight and enhances insulin sensitivity without alteration of serum adiponectin levels in obese patients with Type 2 diabetes.

Metabolic characteristics in individuals with impaired glucose homeostasis

We sought to clarify whether impaired fasting glucose (IFG), impaired glucose tolerance (IGT) or both (IFG/IGT) represent the most severe impairment in insulin resistance (IR) and insulin secretion. Among the 159 Chinese subjects, 21 were diagnosed as having IFG, 103 as having IGT and 35 as having both. IR and beta-cell function were assessed using homeostatic model assessment (HOMA) and an insulin-suppression test (IST). No differences were evident between the groups in blood pressure, body mass index, plasma insulin fasting levels and lipid profiles. However, plasma 2-h insulin levels were higher in the IGT and IFG/IGT groups. Beta-cell functions were not different between these groups. But, the result of glucose tolerance was different, in which the IFG/IGT and IFG groups displayed higher insulin sensitivity than IGT via HOMA instead of no difference via IST in the three patient groups.

Distally based sural island flap for the reconstruction of a large soft tissue defect in an open tibial fracture with occluded anterior and posterior tibial arteries—a case report

To repair a 10 x 16 cm soft tissue defect of right lower leg that accompanied with occluded anterior and posterior tibial arteries in a 30-year-old man who sustained comminuted type III(B) Gustilo open tibial and fibular fracture, we present a successful reconstruction by using a large distally based sural island flap perfused by the lowermost perforator of the peroneal artery. This flap is a useful alternative for distal extremity reconstruction when anterior and posterior tibial arteries are occluded, as large flaps can be elevated safely based on only one peroneal perforator.

Multiple-event study of bioretention for treatment of urban storm water runoff

Bioretention is a novel best management practice for urban storm water, employed to minimize the impact of urban runoff during storm events. Bioretention consists of porous media layers that can remove pollutants from infiltrating runoff via mechanisms that include adsorption, precipitation, and filtration. However, the effectiveness of bioretention in treating repetitive inputs of runoff has not been investigated. In this study, a bioretention test column was set up and experiments proceeded once every week for a total of 12 tests. Through all 12 repetitions, the infiltration rate remained constant (0.35 cm/min). All 12 tests demonstrated excellent removal efficiency for TSS, oil/grease, and lead (99%). For total phosphorus, the removal efficiency was about 47% the system removal efficiency ranged from 2.3% to 23%. Effluent nitrate concentration became higher than the influent concentration during the first 28 days and removal efficiency ranged from 9% to 20% afterward. Some degree of denitrification was apparently proceeding in the bioretention system. Overall, the top mulch layer filtered most of TSS in the runoff and prevented the bioretention media from clogging during 12 repetitions. Runoff quality was improved by the bioretention column.

The effect of surgical stress on insulin sensitivity, glucose effectiveness and acute insulin response to glucose load

Hyperglycemia after stress is a very common clinical phenomenon. It is generally hypothesized that the underlying cause is a neuroendocrine-mediated deterioration in glucose metabolism. However, the detailed roles of insulin sensitivity, glucose effectiveness and acute insulin response to glucose load in response to stress have not been well established. Hernioplasty was used as a minor stress model for studying stress-induced hyperglycemia. Eleven healthy young men were enrolled voluntarily in this study. Their mean age was 22.0 +/- 0.9 yr and BMI 23.3 +/- 0.6 kg/m2. Frequently sampled i.v. glucose tolerance tests were performed one day before and one day after the surgery. Insulin sensitivity (SI), glucose effectiveness (EG) and area under acute insulin response (AIR) were calculated from "minimal model" algorithms. We also measured fasting concentrations of human GH, ACTH and F on the days of the test. Compared to the pre-operation data, levels of ACTH and F did not change significantly after the surgery. Only GH levels were marginally significant. On the other hand, the SI (0.75 +/- 0.1, 0.52 +/- 0.9 x 10(-5) min(-1)/pmol, p = 0.04), EG (0.023 +/- 0.03, 0.016 +/- 0.003 min(-1), p = 0.01) and AIR (6738.5 +/- 1111.6, 5130.0 +/- 1047.2 pmol, p = 0.005) were all significantly decreased after surgery. The percentages of decrease were 16.3 +/- 15.5, 32.1 +/- 10.3 and 17.8 +/- 10.3%, respectively. Finally, only the changes of EG positively correlate with the changes of ACTH before and after surgery. No significant changes were noted among other stress hormones and the changes of SI, EG and AIR. In conclusion, hernioplasty results in reduced SI, EG and AIR. Among them, although not statistically significant, the EG showed the most distinct decrease after the surgery, which has not been found in previous literature.

Geometric and statistical properties of the mean-field hydrophobic-polar model, the large-small model, and real protein sequences

Lattice models, for their coarse-grained nature, are best suited for the study of the "designability problem," the phenomenon in which most of the about 16 000 proteins of known structure have their native conformations concentrated in a relatively small number of about 500 topological classes of conformations. Here it is shown that on a lattice the most highly designable simulated protein structures are those that have the largest number of surface-core switchbacks. A combination of physical, mathematical, and biological reasons that causes the phenomenon is given. By comparing the most foldable model peptides with protein sequences in the Protein Data Bank, it is shown that whereas different models may yield similar designabilities, predicted foldable peptides will simulate natural proteins only when the model incorporates the correct physics and biology, in this case if the main folding force arises from the differing hydrophobicity of the residues, but does not originate, say, from the steric hindrance effect caused by the differing sizes of the residues.

Reoperative Snodgrass procedure

PURPOSE

We examine the results of a reoperative Snodgrass procedure for complex hypospadias.

MATERIALS AND METHODS

A total of 25 patients with hypospadias in whom repair had failed underwent a reoperative Snodgrass procedure. Mean patient age and number of prior repairs were 11.4 years and 2.5, respectively. Before this treatment the meatus was at the distal shaft in 10 cases, mid shaft in 9, proximal shaft in 4 and penoscrotal junction in 2. Preoperatively the associated complications were fistulas in 13 patients, residual chordee in 12 and diverticulum in 1. In 8 cases the fistula was incorporated into the hypospadiac opening and treated as a longer defect. The urethral plates were, subjectively, surgically altered or unaltered in 7 and 18 patients, respectively. In 8 patients (group A) the previous repair(s) did not involve dissection of the urethral plate (unaltered) nor was there a fistula. The remaining 17 patients were classified as group B. The neourethra was then reconstructed as the Snodgrass technique. Followup urethral calibration was performed in 17 patients.

RESULTS

Mean followup period was 13.7 months. Mean length and size of neourethra were 19.9 mm. and 14Fr, respectively. There were 7 (28%) postoperative fistulas of the neourethra. The incidences of postoperative fistula of the neourethra were 0% and 41.2% in groups A and B, respectively (p <0.01). Statistically the surgically altered urethral plate and the presence of a preoperative fistula were 2 independent factors predicting a higher postoperative fistula rate. The overall postoperative meatal stenosis rate was 13 (52%) with 3 (37.5%) in group A and 10 (58.8%) in group B, respectively (p >0.05). The meatal stenosis was treated with simple dilation in 11 cases and meatoplasty during subsequent fistula repair in 2. Stricture at the anastomostic site between the normal urethra and neourethra was noted in 2 patients. Fistula repair was successfully performed 6 months later in 4 patients.

CONCLUSIONS

The Snodgrass procedure is a viable option for the treatment of previously failed hypospadias repair. It was highly effective in patients with a surgically unaltered urethral plate and no preoperative fistula.

Three-dimensional mapping of brain neuropils in the cockroach, Diploptera punctata

Herein, we present a complete three-dimensional (3D) map of major neuropil structures in the central brain of the cockroach Diploptera punctata. The positions of the structures have been ascertained by confocal microscopy, which, until now-for reasons of tissue opacity and nonhomogeneity-has been thought impractical in imaging fluorescently labeled structures thicker than 150 microm. In this report, however, we have used digestive enzymes and microwave-aided fixation to stain, clear, and optically section, in its entirety, an intact central brain more than 500 microm thick. The central brain from an adult female cockroach was stained thoroughly with the membrane probe NBD-ceramide and the DNA probe propidium iodide. The central brain as well as such neuropil regions as mushroom bodies, central complex, antennal glomeruli, and lobus glomerulati were individually outlined, segmented, and reconstructed in three dimensions to a spatial resolution of approximately 1 microm in the X-Y plane and 3 microm in the Z plane. The volume and surface area of each neuropil compartment were determined, and Kenyon cells of the mushroom bodies were counted. We determined that each brain hemisphere contains about 230,000 Kenyon cells, 99 antennal lobe glomeruli, and 40 lobus glomerulatus glomeruli. Segmented compartments were assigned as separate channels and merged into a single data base to reconstruct a 3D central brain containing eight different channels. This is the first 3D map at submicron resolution of an entire animal's brain that measures more than 500 microm in thickness.

Sequence variants and functional analysis of human papillomavirus type 16 E5 gene in clinical specimens

Previously, we found that the E5 protein can be expressed in HPV-16 infected precancerous lesions and cervical cancer. In this study, we investigated the presence of sequence variants of E5 in HPV-16 infected tissues. Toward this end, we amplified the E5 gene by polymerase chain reaction from 29 HPV-16 infected tissues including eight normal tissues, seven high grade neoplastic tissues (high grade squamous intraepithelial lesions (HSIL) and 14 cervical cancer tissues. Sequence analysis demonstrated that there were three mutational hot spots at positions 3979, 4042, and 4077 of the HPV-16 DNA; these and other mutations resulted in six variants in the E5 sequence. This resulted in four E5 protein mutants, named WTE5 [wild type E5 protein], 14E5, 21E5 and 56E5. Functional analysis of these four mutant proteins revealed that the transforming activities of 14E5, 21E5 and 56E5 were 0.95, 0.59, and 0.89 fold of WTE5, respectively. Although E5 was expressed in all of the HSIL and cervical cancer tissues, but in only one of the eight normal tissues tested, only WT E5 protein was found in HSIL while in cervical cancer tissues both WT and mutant E5 proteins were detected. Since these E5 proteins exhibited the same in vitro transforming activity, these data suggest that expression of E5 is important in development and progression toward malignancy but mutation of E5 does not affect the transformation process.

Tubularized incised plate urethroplasty for proximal hypospadias

OBJECTIVE

To review our experience of using the tubularized incised plate (TIP) urethroplasty (useful in the treatment of distal hypospadias) to treat proximal hypospadias.

MATERIALS AND METHODS

From March 1997 to March 2000 primary repairs were carried out on 40 boys (mean age 4.5 years) with proximal hypospadias. After degloving the penile skin the meatus was at the mid-shaft in 10 boys, at the proximal penile shaft in 11, at the penoscrotal junction in 16, at the scrotum in two and at the perineum in one. The 21 patients with a mid or proximal shaft meatus were categorized as having mid-shaft and the other 19 as having posterior hypospadias. Tunica albuginea plication (TAP) was used to correct residual ventral curvature. The method of urethroplasty was adapted from that described by Snodgrass. The key step of the TIP repair is a midline incision of the urethral plate; a subcutaneous tissue flap dissected from the inner prepuce is used to cover the neourethra. An 8 or 10 F nasogastric tube is used as a urethral stent and removed 7 or 8 days after surgery. Follow-up endoscopy and urethral sounding were carried out in 17 of the patients aged < 6 years; the mean follow-up was 12.5 months.

RESULTS

TAP was used to correct penile curvature in nine (23%) of the patients. Excluding stenosis, the TIP repair was successful in 20 (90%) of those with mid-shaft and in 16 of the 19 with posterior hypospadias; for all complications the respective rates were 19 of 22 and 15 of 19. The overall success rate was 88% for all 40 patients with proximal hypospadias; a urethrocutaneous fistula occurred in two of those with mid-shaft and three of those with posterior hypospadias. Urethral meatal stenosis occurred in four (12%) of the patients (two in each group); two were associated with a fistula and the other two had only mild meatal stenosis. The overall complication rate was 17.5% (three and four in the mid and the posterior hypospadias groups, respectively). The meatal stenosis was managed by simple dilatation in three and meatoplasty in one patient. Endoscopically, the mucosa of neourethra was pink and smooth in all 17 patients assessed. The calibre of all 17 neourethra was > or = 8 F and in 13 was > or = 10 F.

CONCLUSION

TIP repair is a reliable method for treating both mid-shaft and posterior hypospadias.

Induction of CD8 T cells by vaccination with recombinant adenovirus expressing human papillomavirus type 16 E5 gene reduces tumor growth

The potential of the E5 protein as a tumor vaccine candidate has not been explored yet. In this study, we evaluate the human papillomavirus type 16 (HPV-16) E5 protein delivered by an adenovirus vector as a tumor vaccine for cervical lesions. The results demonstrate that a single intramuscular injection of a recombinant adenovirus carrying the HPV-16 E5 gene into syngeneic animals can reduce the growth of tumors which contain E5 gene expression. Moreover, the E5 vaccine-induced tumor protection occurs through CD8 T cells but not through CD4 T cells in in vitro assays. In addition, our studies using knockout mice with distinct T-cell deficiencies confirm that cytotoxic T-lymphocyte-induced tumor protection is CD8 dependent but CD4 independent. Hence, HPV-16 E5 can be regarded as a tumor rejection antigen.

Tyr115, gln165 and trp209 contribute to the 1, 2-epoxy-3-(p-nitrophenoxy)propane-conjugating activity of glutathione S-transferase cGSTM1-1

We investigated the epoxidase activity of a class mu glutathione S-transferase (cGSTM1-1), using 1,2-epoxy-3-(p-nitrophenoxy)propane (EPNP) as substrate. Trp209 on the C-terminal tail, Arg107 on the alpha4 helix, Asp161 and Gln165 on the alpha6 helix of cGSTM1-1 were selected for mutagenesis and kinetic studies. A hydrophobic side-chain at residue 209 is needed for the epoxidase activity of cGSTM1-1. Replacing Trp209 with histidine, isoleucine or proline resulted in a fivefold to 28-fold decrease in the k(cat)(app) of the enzyme, while a modest 25 % decrease in the k(cat)(app) was observed for the W209F mutant. The rGSTM1-1 enzyme has serine at the correponding position. The k(cat)(app) of the S209W mutant is 2. 5-fold higher than that of the wild-type rGSTM1-1. A charged residue is needed at position 107 of cGSTM1-1. The K(m)(app)(GSH) of the R107L mutant is 38-fold lower than that of the wild-type enzyme. On the contrary, the R107E mutant has a K(m)(app)(GSH) and a k(cat)(app) that are 11-fold and 35 % lower than those of the wild-type cGSTM1-1. The substitutions of Gln165 with Glu or Leu have minimal effect on the affinity of the mutants towards GSH or EPNP. However, a discernible reduction in k(cat)(app) was observed. Asp161 is involved in maintaining the structural integrity of the enzyme. The K(m)(app)(GSH) of the D161L mutant is 616-fold higher than that of the wild-type enzyme. In the hydrogen/deuterium exchange experiments, this mutant has the highest level of deuteration among all the proteins tested. We also elucidated the structure of cGSTM1-1 co-crystallized with the glutathionyl-conjugated 1, 2-epoxy-3-(p-nitrophenoxy)propane (EPNP) at 2.8 A resolution. The product found in the active site was 1-hydroxy-2-(S-glutathionyl)-3-(p-nitrophenoxy)propane, instead of the conventional 2-hydroxy isomer. The EPNP moiety orients towards Arg107 and Gln165 in dimer AB, and protrudes into a hydrophobic region formed by the loop connecting beta1 and alpha1 and part of the C-terminal tail in dimer CD. The phenoxyl ring forms strong ring stacking with the Trp209 side-chain in dimer CD. We hypothesize that these two conformations represent the EPNP moiety close to the initial and final stages of the reaction mechanism, respectively.