[The application of full-length urethral preservation without anastomosis in single-port laparoscopic radical prostate cancer].

Objective: To preliminarily examine the feasibility and outcome of single-port laparoscopic radical prostatectomy with full-length urethral preservation (FLUP-SPRP). Method: This study was a prospective case series study. A total of 25 patients with prostate cancer who met the enrollment criteria and agreed to this surgical procedure from March 2022 to December 2022 were collected at the Department of Urology, the Second Affiliated Hospital of Nanjing Medical University. The age of the patients was (67.2±7.6) years (range: 61 to 76 years). This novel procedure was performed by an experienced surgeon who performed single hole radical prostatectomy skillfully. Patient urinary control, tumor control, and related surgical complications after surgery were regularly monitored. Postoperative urinary control was evaluated using the daily amount of urine pad, 0 to 1 piece of urine pad was to restore urinary control, and 0 to 1 piece of pad within 24 hours after catheter removal was immediate urinary control. Result: All prodecures were successfully completed without transit to open surgery. The surgical time was (128.4±22.4) minutes (range: 100 to 145 minutes), the intraoperative blood loss was (68.2±13.7) ml (range: 50 to 120 ml). The urethral injury occurred in 4 cases during surgery and was repaired by sutures. The urinary control recovery rates within 24 hours, 1 week, 4 weeks, and 7 weeks after surgery were 80.0%, 84.0%, 92.0% and 100%, respectively. Postoperative large section pathology revealed 1 case with a positive basal margin of the prostate and negative margins of all prostate glands around the urethra. Postoperative complications included urinary tract infection in 3 cases, urodynia in 2 cases, and acute urinary retention in 1 case. MRI follow-up 3 months after surgery showed normal anatomy of the bladder and urethra. The follow-up values of prostate specific antigen at 3 and 6 months after surgery were less than 0.1 µg/L. Conclusions: The preliminary results of this study indicate that the FLUP-SPRP procedure is safe and feasible. The early results of postoperative urinary control and oncology are as expected.

Lipid accumulation and oxidative stress in the crop tissues of male and female pigeons during incubation and chick-rearing periods.

The current study aimed to evaluate the changes in lipid accumulation and oxidative status in pigeon crops during different breeding stages. Forty-two pairs of adult pigeons were randomly assigned to 7 groups. Lipid droplet accumulation in pigeon crops was visualized by using oil red O staining from d 17 of incubation (I17) to d 7 of chick rearing (R7). Transmission electron microscopy analysis showed swollen mitochondria with disintegration of cristae and typical characteristics of endoplasmic reticulum stress in crop tissues at R1 compared with those at I4. During the peak of pigeon milk formation, the concentrations of reactive oxygen species, and oxidative damage markers (advanced oxidation protein products, 8-hydroxy-2 deoxyguanosine, and malondialdehyde) and the enzyme activities of total superoxide dismutase and glutathione peroxidase were all elevated significantly (P < 0.05). The protein concentration of B-cell lymphoma-2 associated X in crop tissues was significantly higher at R1, while the level of B-cell lymphoma-2 protein in males was the highest at I4 (P < 0.05). The ratio of B-cell lymphoma-2 associated X protein (Bax)/B-cell lymphoma-2 (Bcl-2) in both male and female crops peaked at R1 (P < 0.05). Gene expression of the key enzymes involved in mitochondrial and peroxisomal fatty acid ß-oxidation was investigated in crops. In males, the gene expression of carnitine palmitoyltransferase 1a peaked at R15, and that of carnitine palmitoyltransferase 2 increased significantly from R1 to R15 (P < 0.05). The mRNA abundance of long chain 3-hydroxyacyl-CoA dehydrogenase increased to the maximum value at R1 and I17 in males and females, respectively. From I17 to R7, the mRNA levels of acyl-CoA oxidase 1 and acyl-CoA oxidase 2 were decreased in pigeon crops (P < 0.05). Conclusively, lipid droplet accumulation was found in male and female pigeon crops from the end of incubation to the early stage of chick rearing. Although antioxidant defence and mitochondrial fatty acid ß-oxidation were both mobilized, oxidative stress in crop tissues still occurred during the peak of milk formation.

[Efficacy observation of long-segment pedicle screw reduction and internal fixation combined with kyphoplasty in the treatment of stage â ¢ reducible Kummell disease].

Objective: To investigate the clinical efficacy of long-segment pedicle screw reduction and internal fixation combined with kyphoplasty in the treatment of stage Ⅲ reducible Kummell disease. Methods: The clinical data of 32 patients with stage Ⅲ reducible Kummell disease treated at the Department of Orthopedics, Sir Run Run Shaw Hospital, Zhejiang University College of Medicine from January 2012 to March 2017 were analyzed retrospectively.There were 7 males and 25 females,aged (71.8±6.7)years(range:61 to 86 years).The injured segment was T10 in 1 patient,T11 in 8 patients,T12 in 13 patients,L1 in 7 patients,L2 in 2 patients and L3 in 1 patient.Preoperative American spinal injury association(ASIA) classification of patients all showed grade D.Bone mineral density (BMD),spinal X-ray,CT and MRI were examined before operation.All patients were treated with postural reduction, long-segment pedicle screw reduction and internal fixation combined with kyphoplasty.The operation time,intraoperative blood loss,length of stay and postoperative complications were recorded.The visual analogue scale (VAS) and Oswestry dysfunction index (ODI) as well as the BMD of hip were collected before and after operation.The Cobb angle of involved segment kyphosis and the height of anterior edge of diseased vertebrae were measured before operation,3 days and 12 months after operation.CT-related parameters were measured before and 3 days after operation,including sagittal anterior and posterior diameter of spinal canal,cross-sectional anterior and posterior diameter of spinal canal and cross-sectional spinal canal area.Paired sample t test and repeated measures were used to compare the data before and after operation. Results: All patients received the operation successfully.The operation time was (131.3±16.9) minutes (range:95 to 180 minutes),the blood loss was (82.5±27.1) ml (range:50 to 150 ml),and the length of stay was (8.3±2.4) days (range:5 to 14 days).All patients were followed up for more than 12 months.The VAS decreased gradually at 3 days,3 months,6 months and 12 months after operation,and the differences were statistically significant compared with the VAS before surgery (all P<0.01).ODI at 3,6 and 12 months after surgery was significantly improved compared with that before surgery(All P<0.01).The CT-related parameters at 3 days after operation were significantly higher than those before operation (All P<0.05).At 12 months after surgery,the Cobb angle decreased from (35.2±7.6) ° preoperatively to (4.3±1.7) ° (t=22.630,P<0.01),the height of anterior edge of diseased vertebrae increased from (4.3±1.0) mm preoperatively to (16.9±2.5) mm(t=-25.845,P<0.01),the bone mineral density of hip increased from -(2.2±0.6) preoperatively to -(2.8±0.6)(t=-0.040,P<0.01).Up to the last follow-up,2 patients had distal pedicle screw loosening, 1 patient had proximal junctional kyphosis,and there was no new vertebral fracture. Conclusions: Based on postural reduction,long-segment pedicle screw reduction and internal fixation combined with kyphoplasty is a safe and effective treatment method for stage Ⅲ reducible Kummell disease,which can reconstruct the stability of the diseased vertebrae.Postoperative standard anti-osteoporosis treatment is the basis to ensure the efficacy.

Effect of Akt activation on apoptosis-related gene expression in the crop tissues of male and female pigeons (Columba livia).

The current study investigated whether the expression of apoptosis genes in the pigeon crops was affected by the Akt signaling pathway during crop milk formation. First, 78 pairs of adult White King pigeons were randomly assigned to 7 groups, and the expression of apoptosis-related genes and Akt signaling pathway-related proteins in the crop tissues during different breeding stages were examined. The results showed that the mRNA levels of Bak, caspase-3, caspase-6, and caspase-9 in female crops all increased and reached their highest levels at d 17 of incubation (I17). In male crops, the levels of caspase-3 and caspase-9 gene expression peaked at d 1 of chick rearing (R1). The lowest level of Bcl-2 gene expression in females was observed at I17. The expression ratios of p-Akt (Ser473)/Akt and p-Akt (Thr308)/Akt in male crops decreased to their minimum at R1, while it was observed at d 7 of chick rearing (R7) in females. Second, 36 pairs of adult pigeons were divided into 3 groups and were subjected to SC79 injections with dosages of 0, 0.02, or 0.04 mg/kg bodyweight. The SC79 injections resulted in a considerable decrease in growth performance of pigeon squabs. In male crops, the expression ratios of p-Akt (Ser473)/Akt and p-Akt (Thr308)/Akt were significantly elevated in the 0.02 mg/kg SC79 group, while in female crops, they were higher in the 0.04 mg/kg SC79 group (P < 0.05). The SC79 injection inhibited the gene expression of Bak in female crops, but enhanced the gene expression of Bcl-2 in both male and female crops. In the 0.04 mg/kg SC79 group, a 50.7 to 75.7% decrease was observed in the expression of caspase-3, caspase-6, and caspase-9 in male and female pigeon crops. Expression of the caspase-8 gene and total Akt protein in pigeon crops was not changed in different breeding stages or after SC79 injection. In conclusion, the expression of genes related to mitochondria-dependent apoptosis can be regulated by the Akt signaling pathway, which may play a potential role in pigeon milk formation.

[Activation of GPER inhibts proliferation and autophagy in prostatic epithelial cells].

Objective: To investigate the effect of G protein-coupled estrogen receptor (GPER) on proliferation and autophagy in prostatic epithelial cells. Methods: Cell Counting Kit-8 (CCK8) assay was used to observe the growth of BPH-1 and RWPE-1 cells after treating with or not with estradiol or GPER selective agonist G1. Autophagy was quantified with Western blot and Cyto-ID autophagy detection kit after treating with estradiol, G1 or both G1 and G15 in the same cells. Results: The OD value in estrogen group and G1 group was significantly lower than those in control group (P<0.01). Compared with control group, Western blot and Cyto-ID green reagent staining revealed that the ratio of LC3Ⅱ/LC3Ⅰ and the relative fluorescence intensity of BPH-1 and RWPE-1 cells were decreased in G1 group and estradiol group (P<0.01). Pretreatment with G15 reversed the effect of G1 (P<0.05). Conclusion: The activation of GPER leads to the inhibition of autophagy and cell proliferation.

Prognostic value of ZFP36 and SOCS3 expressions in human prostate cancer.

PURPOSE: ZFP36 ring finger protein (ZFP36) and the suppressor of cytokine signaling 3 (SOCS3) have been reported to, respectively, regulate NF-κB and STAT3 signaling pathways. To better understand the correlation of NF-κB and STAT3 negative regulates pathway, we have investigated the involvement of ZFP36 and SOCS3 expressions in human prostate cancer (PCa). METHODS: In the present study, paired patient tissue microarrays were analyzed by immunohistochemistry, and the ZFP36 protein expression was quantitated as immunoreactive scores in patients with PCa. Associations between ZFP36/SOCS3 expression and various clinicopathological features and prognosis of PCa patients were statistically analyzed based on the Taylor database. Then, the functions of ZFP36 and SOCS3 in cancerous inflammation were determined using qPCR and immunohistochemistry in vitro and in vivo. RESULTS: ZFP36 protein expression in PCa tissues was significantly lower than those in non-cancerous prostate tissues (P < 0.05). In mRNA level, ZFP36 and SOCS3 had a close correlation with each other (P < 0.01, Pearson r = 0.848), and its upregulation was both significantly associated with low Gleason score (P < 0.001 and P < 0.001, respectively), negative metastasis (P < 0.001 and P < 0.001, respectively), favorable overall survival (P < 0.001 and P < 0.05, respectively), and negative biochemical recurrence (P < 0.001 and P < 0.001, respectively). Functionally, LPS treatment could lead to the overexpression of ZFP36 and SOCS3 in vitro and vivo. CONCLUSIONS: Our data offer the convincing evidence for the first time that the aberrant expressions of ZFP36 and SOCS3 may be involved into the progression and patients' prognosis of PCa, implying their potentials as candidate markers of this cancer.

Learning curve and outcome of laparoscopic transcystic common bile duct exploration for choledocholithiasis.

BACKGROUND: The best approach for cholecystocholedocholithiasis remains a matter of debate. The aim of this study was to evaluate the technical aspects, learning curve and outcome of laparoscopic transcystic common bile duct exploration (LTCBDE). METHODS: Patients who underwent laparoscopic cholecystectomy with LTCBDE between January 2007 and December 2012 were identified from an institutional database. Data on preoperative investigations, intraoperative and postoperative findings were retrieved retrospectively from the patients' hospital notes. RESULTS: There were 399 women (56·4 per cent) and 309 men (43·6 per cent), with a median age of 58 (range 18-87) years. Microincision (incision of the cystic duct at the confluence with the common bile duct (CBD) with extension of only 3-5 mm at the lateral margin of the CBD) and lithotripsy were used in the transcystic exploration in 119 patients, and increased the success rate of LTCBDE from 74·2 to 91·0 per cent. The median duration of operation was 85 (i.q.r. 65-120) min and the median postoperative hospital stay was 2 (1-3) days. Retained common bile duct stones were observed in 13 patients, and postoperative complications developed in 27 patients. The cumulative sum duration of operation learning curve comprised two phases; phase 1 included the first 250 patients and phase 2 the remaining 458 patients. Duration of operation and postoperative hospital stay decreased with increasing volume per surgeon. Recurrence of common bile duct stones was diagnosed in 26 patients during a median follow-up of 4 years. CONCLUSION: LTCBDE with or without microincision and/or lithotripsy is a safe and effective approach.

Effects of ischemic preconditioning in the late phase on homing of endothelial progenitor cells in renal ischemia/reperfusion injury.

OBJECTIVE: The aim of this study was to determine whether the mobilization and recruitment of endothelial progenitor cells (EPCs) contribute to the protection of kidneys from ischemia/reperfusion (I/R) injury after ischemic preconditioning (IPC) during the late phase. METHODS: Seventy-five male Sprague-Dawley rats were divided into the following groups: sham-operated (group A; n = 25), ischemia/reperfusion hosts that underwent 45 minutes of left renal artery ischemia (group B; n = 25), and ischemic preconditioning-treated group (group C; n = 25). Group C underwent 3 cycles of 5 minutes of occlusion and 5 minutes of reperfusion followed by 24 hours of reperfusion before the following 45 minutes of occlusion. Serum samples were collected and renal tissues harvested for histological examination terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, immunohistochemical staining, and Western blot analysis to determine the expression levels of CD34, VEGFR-2 (Vascular Endothelial Growth Factor Receptor 2)/flk-1, vascular endothelial growth factor (VEGF), and stromal cell-derived factor-1α (SDF-1α). RESULTS: Compared with group B, the levels of blood urea nitrogen (BUN), serum creatinine (Scr) and acute tubulointerstitial injury at 24 hours after operation were significantly reduced in group C. At 72 hours, tubular epithelial cell apoptosis was also decreased (17.6 ± 4.45 vs 63.8 ± 6.10; P < .01). CD34+ and flk-1+ cells that mostly accumulated in the medullopapillary parenchyma were significantly increased at 72 hours (P < .05). Expression levels of VEGF and SDF-1α were also significantly higher in group C (P < .05). CONCLUSION: The present work suggested that IPC protected kidneys from IR injury in the later phase through enhanced mobilization and recruitment of EPCs. VEGF and SDF-1α may play important roles in this protective effect.

Experimental study on early protective effect of ischemic preconditioning on rat kidney graft.

OBJECTIVE: Our aim was to investigate the mechanisms of early protection by ischemic preconditioning (IPC) of transplanted rat kidneys. MATERIALS AND METHODS: Thirty-six male donor and recipient Sprague-Dawley (SD) rats were randomly divided into 3 groups: sham-operated (A), transplantation (B), and IPC treatment (C) groups. Group A underwent exploratory laparotomy, group B received orthotopic transplantation, and group C, 15 minutes of ischemia followed by 10 minutes of reperfusion before transplantation. We measured the serum creatinine (SCr), blood urea nitrogen (BUN), and degree of kidney graft ischemic/reperfusion injury (IRI) by tumor necrosis factor-alpha (TNF-alpha) IkappaB kinase beta (IKK-beta) nuclear factor-kappa beta (NF-kappabeta) p65 subunit mRNA expressions. RESULTS: The SCr and BUN levels in groups C and B were higher than those in the sham-operated group (P < .01), without a significant difference between groups C and B at 24 hours after transplantation (P > .05). The degree of renal graft tubular injury in group C was significantly lower than that in group B (P < .01). TNF-alpha transcription levels at 24 hours after transplantation were significantly lower compared with the non-IPC group (P < .01). However, we failed to note a significant difference in IKK-beta or p65 mRNA expressions between groups C and B (P > .05). CONCLUSIONS: One cycle of preconditioning (15 min/10 min) attenuated renal graft IRI in the early phase. The inhibiting effects on TNF-alpha and the positive feedback signaling of TNF-alpha/NF-KB pathways may play important roles in renal graft protection.

Ischemic preconditioning improves rat kidney allograft function after ischemia/reperfusion injury: the role of tumor necrosis factor-alpha.

OBJECTIVE: The aim of this study was to investigate the early protection of ischemic preconditioning (IPC) and its mechanisms in transplanted rat kidneys. MATERIALS AND METHODS: Thirty-six male Sprague-Dawley (SD) rat donors and recipients were randomly divided into the following groups: sham-operated group (A; n = 6); untreated transplantation group (B; n = 6); and treatment group (C; n = 6). Group A was subjected to exploratory laparotomy. Group B received orthotopic transplantation. Group C underwent a 15-minute period of ischemia followed by a 10-minute reperfusion before orthotopic transplantation. We assessed the serum creatinine (SCr), blood urea nitrogen (BUN), and to evaluate the degree of kidney graft ischemia/reperfusion injury: tumor necrosis factor-alpha (TNF-alpha), IkappaB kinase-beta (IKK-beta), and nuclear factor-kappa B (NF-kappaB) P65 subunit mRNA expressions. RESULTS: The levels of SCr and BUN in groups C and B were greater than in the sham-operated group (P < .01), but there was no significant difference between the C and B groups at 24 hours after transplantation (P > .05). The degree of renal graft tubular injury in group C was significantly less compared with group B (P < .01). TNF-alpha transcription levels at 24 hours after transplantation were significantly less compared with the non-IPC group (P < .01). However, no significant difference was observed in IKK-beta mRNA and P65 mRNA expressions between groups C and B (P > .05). CONCLUSIONS: A 1-cycle schedule of preconditioning (15 min/10 min) attenuated renal graft ischemia/reperfusion injury in the early phase. IPC can improve rat kidney allograft function after ischemia/reperfusion injury. The inhibitory effects on TNF-alpha and on positive feedback signaling of TNF-alpha/NF-kappaB pathways may play important roles in renal graft protection in the early stage.

[Cloning and expression of human anti-colonic cancer single-chain Fv fragment].

We report a new strategy for the generation of human anticolon cancer monoclonal antibodies based on the molecular cloning and expression of immunoglobulin variable region cDNAs derived from peripheral blood mononuclear cells (PBMC) that were transformed by EBV. The immortalized B cells secreting tumor-specific antibodies were identified by HRT-18 cell ELISA and cloned by limiting dilution. Heavy- and light-chain VH-CH1 (gamma) and V kappa-C kappa cDNAs were rescued from ELISA-positive cells wells by RT-PCR. VH and V kappa were amplified by 2nd PCR and linked them together by 3rd PCR assembly with the use of a (Gly4Ser)3 linker. The ScFv cDNAs were then cloned into the fUSE 5 vector and displayed on phage. Phage clones were selected on HRT-18 cells and normal human PBMC. ELISA tested phage clones randomly picked after each panning step. > 80% of the clones showed a strong ELISA reaction, demonstrating the effectiveness of the panning procedure for selecting anticolon cancer antibodies. This approach offers an effective method by combining in vitro immunization, B-cell expansion for enrichment of specific B-lymphocytes, PCR gene cloning and phage display to make high-affinity human anticolon cancer monoclonal antibody molecules.

[Study of monoclonal anti-idiotype antibody that bears the internal image of nasopharyngeal carcinoma associated antigen].

We prepared anti-idiotypic monoclonal antibodies (Ab2) against FC2 and HNL5 that recognized as nasopharyngeal cancer (NPC) associated antigens. These Ab2, which designated as 2H4 and 5D3, could inhibit the binding of FC2 or HNL5 to NPC cell lines. The anti-sera from the immunized mice that contained anti-anti-idiotype antibodies (Ab3) could compete with FC2 or HNL5 for binding with NPC cell by a competitive inhibition assay. When 2H4 or 5D3 immunized mice coupled with keyhole limpet hemocyanin(KLH), positive and specific delayed-type hypersensitivity (DTH) reaction occurred after the mice were stimulated by NPC cells. The proliferative response of the splenocytes was significantly higher in experimental groups than that in control groups. Therefore, it is suggested that the anti-idiotypic antibodies (Ab2) 2H4 and 5D3 are the Ab2 beta bearing the internal image of the epitope of NPC associated antigen, that either 2H4 or 5D3 expressing three dimensional shapes which resemble the structure of natural antigens can induce humoral and cellular immune response.

An efficient method for small field treatment dose calculation for stereotactic radiosurgery using a LINAC.

The normal procedure for a physician-physicist team designing a treatment plan for multiarc stereotactic radiosurgery is the trial-and-error approach of changing the collimator size and the location of the isocenter of radiation and viewing the isodose curves on two-dimensional computed tomography (CT) or magnetic resonance imaging (MRI) image planes. Automatic optimization procedures have also been used to optimize beam weight or beam size. However, either process is very time consuming. To improve the speed of the dose calculation, a random sampling method has been proposed. Unfortunately, the sampled values of an objective function are different from one sample to another. Such a sampling method cannot be used in automatic optimization because the next move in an optimization process is based on the current and past objective function values. To this end, an adaptive method based on the size of the collimators is proposed and used to determine a small volume in the shape of a hollow sphere for which the dose is calculated. With an appropriate choice of an adaptive hollow sphere, the objective function calculated based on such a hollow sphere is the same as that calculated with the traditional three-dimensional (3-D) cube matrix. However, with the new adaptive method, the speed of calculating a dose can be improved by a factor of 4 to a factor of 100. Because of the improvement in the speed of calculating a treatment dose, the new adaptive hollow sphere method for calculating a treatment dose can be used routinely in designing a treatment plan.

[Studies on preparation and characteristics of cisplatin chitosan microspheres].

In this paper, the preparation, drug content, size and size distribution, appearance and morphology, release characteristics in vitro and degradation characteristics of cisplatin chitosan microspheres (CDDP-DAC-MS) were studied. CDDP-DAC-MS were prepared by emulsion-crosslink technique. The CDDP-DAC-MS was shown to have rough spherical surface under scanning electron microscopy. The average diameter of the microspheres was 74.80 microns and CDDP content was 20.83% +/- 0.36%. CDDP-DAC-MS swelled slightly in saline after 1 h. Within the test period, the release of CDDP from CDDP-DAC-MS in saline solution could be described by first-order equation. The microspheres were sterilized by 60Co radiation. After 28 d of hepatic artery embolization with CDDP-DAC-MS in dogs, pathological photomicrograph showed that CDDP-DAC-MS could still be observed.

[Studies on hepatic arterial embolization with cisplatin-chitosan-microspheres in dogs].

Cisplatin-chitosan-microspheres (CDDP-DAC-MS) was chosen as a model preparation. Pharmacokinetics, targeting and embolization effects and alteration of liver function were studied after hepatic arterial embolization in dogs with CDDP-DAC-MS, and the platinum content in plasma and liver was determined by flameless atomic absorption spectrophotometry (FAAS). The result of clinical trial was also reported. After the CDDP-DAC-MS and CDDP solution were respectively infused into hepatic artery of dogs through a 5F catheter, the plasma concentration of platinum and AUC of CDDP-DAC-MS group was lower than that of CDDP solution group, but the platinum content in hepatic tissue was 2.92 times as much as that when CDDP solution was given after 24 h. Angiograms revealed a remarkable decrease in the number of arterioles in liver, and histopathologic specimens showed nodular necrosis and hepatic cell degeneration in embolized region. The levels of GPT, GOT and ALP rose transiently after embolization and recovered to normal within 3 weeks. The clinical therapy in six liver cancer patients was successful. It would appear that CDDP-DAC-MS may be a good chemoembolization agent.

Treatment planning optimization for multiple arcs stereotactic radiosurgery using a linear accelerator.

PURPOSE: Multiarc stereotactic radiosurgery is a technique used to irradiate an intracranial tumor with minimal damage to the surrounding normal tissue. The purpose of this paper is to present a method for and the results from optimizing three dimensional (3D) treatment dose for multiarc stereotactic radiosurgery. METHODS AND MATERIALS: The normal procedure for a physician-physicist team designing a treatment plan for multiarc stereotactic radiosurgery is the trial-and-error approach of changing the collimator size and the isocenter of radiation by viewing the isodose curves on a two dimensional (2D) computed tomography (CT) or magnetic resonance imaging (MRI) image plane. Not only is this time consuming, but the resulting treatment plan is not optimal in most, if not all, cases. One reason for such nonconformal isodose curves is that the same collimator size is used for all arcs. However, it is very difficult to determine manually the different collimator sizes for different arcs. A derivative free optimization method is used to optimize the collimator size for each arc, as well as the 3D coordinates of the isocenter(s). RESULTS: One spherical and two ellipsoidal artificial tumors, and one actual tumor, were used to show the utilities of the optimization process. The 90% isodose curves resulting from optimization conform very well with the tumor; whereas the 90% isodose curves from the conventional method either do not envelop the entire tumor when the collimator size is too small, or a large volume of normal tissue is also irradiated by the 90% dose when the next larger collimator size is used. CONCLUSIONS: When the collimator size for each arc and the location of the isocenters(s) are optimized in a multiarc stereotactic surgery treatment plan, the 90% isodose curve conforms to the tumor much better than when the same collimator size is used for all arcs.

Identification and partial sequence of a cDNA that is differentially expressed in human brain tumors.

Differential display technique was used to identify mRNAs that are differentially expressed in malignant versus benign brain tumors. Using this method, a novel 1.4-kb long cDNA (MM1) clone was isolated and sequenced. The nucleotide and the translated amino acid sequence of MM1 cDNA clone did not show significant homology to any known sequence in the Genebank. The expression of MM1 appears to be almost eightfold higher in glioblastomas compared to low grade astrocytomas and slightly higher in malignant meningiomas than in benign meningiomas. The size of mRNA from northern analysis appears to be 7 kb, which is much higher than the size of the isolated MM1 cDNA clone. Expression of MM1 was also seen in various cell lines derived from human tumors including glioblastomas. Whereas low level expression was seen in kidney, esophagus, liver, lymph node, ovary and testis, none of the other tissues from a total of 18 different human organs showed any MM1 expression.

Androgen receptors in laryngeal carcinoma and their clinical significance.

Specific radioligand [3H] methyltestosterone incubation and dextran-coated charcoal absorption technique (DCC) were used to test cytosol androgen receptors (AR) of laryngeal carcinoma in 33 patients. In all specimens, high level AR ranged from 3 to 16.9 fmol/mg of cytosol protein (mean 10 +/- 3.9 fmol/mg), and dissociation constant was 1.7 x 10(-9) mole. Laryngeal carcinoma is considered a sex hormone-dependent tumor. High level of AR in laryngeal carcinoma may indicate a super-demand on androgen; when the content of AR increases the tumor proliferates perniciously. Antiandrogen endocrine therapy may be helpful in treating laryngeal carcinoma.