Sound transmission loss of multi-layered infinite micro-perforated plates.

In this paper, the sound transmission loss (STL) of multi-layered infinite micro-perforated plates (MPPs) is studied. A prediction model for the STL of the multi-layered infinite MPPs is developed, where each MPP may or may not have a perforation, and the number of MPPs is arbitrary. When the frequency of interest is well below the critical frequency of the plate such that the effect of flexural vibration can be neglected compared to that of the inertia term, the mass is replaced by an equivalent complex mass. For numerical examples, single-, double- and triple-layered MPPs are studied. As the perforation ratio increases, the magnitude of the equivalent complex mass decreases rapidly, which in turn results in a decrease of the STL. It is observed that for very small perforation ratios, the mass-spring resonance frequencies in double- and triple-layered MPPs move toward a higher frequency as the perforation ratios increase. In addition, the dips at the resonance frequencies become blunt with increases in the perforation ratios due to the artificial damping induced by micro-perforations. It is also found that at a high frequency, the STL shows dips regardless of the perforation ratios when the wavenumber and air gap depths satisfy certain conditions.

Study on the factors related with intention of cancer screening among Korean residents: application of information-motivation-behavioral skills model.

This study investigated the relationship between intention of undergoing cancer screening and information, motivation, and behavioral skills using an information-motivation-behavioral skills model. The authors performed a telephone survey of a random sample of 2030 residents aged 30 to 69 years from 6 counties of Gangwon province, South Korea from July 15 to July 25, 2009. Questions about information, motivation, and behavioral skills were examined using a confirmatory factor analysis and relationships among factors were analyzed using a structure equation model. The intention of undergoing cancer screening showed a positive relationship between intention to undergo cancer screening and information(r = .134, P < .001), social norms(r = .059, P = .009), and behavioral skills(r = .129, P < .001). Therefore, comprehensive intervention considering motivation and behavioral skills as well as information is necessary to improve cancer screening rates.

Metastasis of renal cell carcinoma to the bladder.

Renal cell carcinoma is an uncommon source of bladder metastases. Here we report a case of renal cell carcinoma that metastasized to the bladder. A 73-year-old woman complained of gross hematuria. Abdominopelvic computerized tomography showed a bladder mass and a heterogenous enhancing mass in the lower pole of the left kidney with left vein thrombosis. The pathological analysis of the resected bladder specimen revealed metastatic renal cell carcinoma of the clear cell type.

Use of cystoscopic tattooing in laparoscopic partial cystectomy.

PURPOSE: During laparoscopic partial cystectomy (LPC), lesion identification is essential to help to determine the appropriate bladder incisions required to maintain adequate resection margins. The inability to use tactile senses makes it difficult for surgeons to locate lesions during laparoscopic surgery. Endoscopic India ink marking techniques are often used in laparoscopic gastroenterological surgery. We present our experience with performing LPC with India ink during the surgical resection of various bladder lesions. MATERIALS AND METHODS: LPC with cystoscopic fine needle tattooing was performed on 10 patients at our institute. Tattooing was performed at 1- to 2-cm intervals approximately 1 cm away from the outer margin of the lesion with enough depth (the deep muscle layer) under cystoscopic guidance. LPC was performed by the transperitoneal approach. The clinical courses and pathologic results were analyzed. RESULTS: All LPC with cystoscopic tattooing cases were performed successfully. The mean patient age was 39.1 years. The mean operative time was 130.5 minutes, and the mean estimated blood loss was 93 ml. The mean hospital stay was 13.1 days, and the mean duration of indwelling Foley catheterization was 10.7 days. There were no significant intraoperative or postoperative complications except 1 case of delayed urinary leak and 1 case of delayed wound healing. The pathological diagnosis included 1 urachal cancer, 1 urachal remnant, 4 urachal cysts, 2 pheochromocytomas, and 2 inflammatory masses. All specimens showed adequate surgical margins. CONCLUSIONS: Cystoscopic tattooing in LPC is a simple and effective technique to assist in locating pathological bladder lesions intraoperatively. This technique can help to determine appropriate resection margins during LPC without incurring additional complicated procedures.

Skeletal muscle metastases from urothelial cell carcinoma.

Hematogenous metastasis to skeletal muscle from urothelial carcinoma is extremely rare and metastatic disease to skeletal muscle tends to be found in people with advanced-stage neoplasm. We report in this paper a case of left sartorius muscle metastasis from urothelial cell carcinoma. A left nephroureterectomy with bladder cuff excision was performed and revealed a high-grade papillary transitional cell carcinoma (TCC) of the pelvis. And 6 month later, recurrent bladder cancer was found regular cystoscopy and then treated with transurethral resection of the bladder. After 6 times resection of bladder, an invasion into the bladder muscle layer was found. We recommended additional radical cystectomy to prevent the disease from advancing. However, the patient refused additional surgery. 6 month later, the patient complained of left thigh pain, so ultrasonography-guided biopsy of the nodular mass lesion in the left sartorius muscle was performed. The pathological analysis of the biopsy specimen revealed poorly differentiated metastatic urothelial carcinoma.

Neovesical-urethral anastomotic stricture successfully treated by ureteral dilation balloon catheter.

Neovesical-urethral anastomotic stricture is a complication of orthotopic neobladder, with a reported incidence of 2.7% to 8.8%. Strictures of the neovesico-urethral anastomotic site can be treated with regular self-dilation, but high-grade strictures require a surgical procedure involving incision by electrocautery or cold knife. Here we describe a grade III neovesical-urethral anastomotic stricture after an orthotopic bladder substitution that was successfully treated by use of a ureteral dilation balloon catheter.

Haploidy influences Bak and Bcl-xL mRNA expression and increases incidence of apoptosis in porcine embryos.

The objective of this study was to determine developmental pattern, total cell number, apoptosis and apoptosis-related gene expression in haploid and diploid embryos following parthenogenetic activation. In vitro-matured porcine oocytes were activated by electrical pulses and cultured in the absence or presence of cytochalasin B for 3 h. Zygotes with two polar bodies (haploid) and one polar body (diploid) were carefully selected and were further cultured in NCSU 23 medium containing 0.4% bovine serum albumin (BSA) for 7 days. The percentage of development to blastocyst stage was higher (p < 0.01) in the diploid than in the haploid parthenotes. In haploid blastocysts, average total cell number was significantly reduced (p < 0.05) and apoptosis was increased at day 7. The relative abundance of Bcl-xL and Bak mRNA in the diploid blastocysts was similar to that of in vivo-fertilized embryos. However, Bcl-xL was significantly decreased, and Bak mRNA was significantly increased (p < 0.05) in haploid parthenotes compared with the diploid parthenotes. These results suggest that the haploid state affects apoptosis-related gene expression which results in increased apoptosis and decreased developmental competence of haploid parthenotes.

Pronucleus formation, DNA synthesis and metaphase entry in porcine oocytes following intracytoplasmic injection of murine spermatozoa.

The onset of pronucleus formation and DNA synthesis in porcine oocytes following the injection of porcine or murine sperm was determined in order to obtain insights into species-specific paternal factors that contribute to fertilisation. Similar frequencies of oocytes with female pronuclei were observed after injection with porcine sperm or with murine sperm. In contrast, male pronuclei formed 8-9 h following the injection of porcine sperm, and 6-8 h following the injection of murine sperm. After pronucleus formation maternally derived microtubules were assembled and appeared to move both male and female pronuclei to the oocyte centre. A few porcine oocytes entered metaphase 22 h after the injection of murine sperm, but normal cell division was not observed. The mean time of onset of S-phase in male pronuclei was 9.7 h following porcine sperm injection and 7.4 h following mouse sperm injection. Ultrastructural observation revealed that male pronuclei derived from murine sperm in porcine oocytes are morphologically similar to normal male pronuclei in porcine zygotes. These results suggest that species-specific paternal factors influence the onset of pronucleus formation and DNA synthesis. However, normal nuclear cytoplasmic interactions were observed in porcine S-phase oocytes following murine sperm injection.

Male pronuclear formation and sperm mitochondria in porcine oocytes following intracytoplasmic injection of pig or mouse sperm.

In the present study we determined the chromatin organization and fate of introduced mitochondria in porcine embryos following intracytoplasmic injection of pig or mouse sperm cells. At 3, 6, 9 and 12 h following injection of pig or mouse spermatozoa or isolated sperm heads, the oocytes were fixed and stained with propidium iodide. Between 3 and 6 h following injection, both porcine and murine sperm chromatin developed into pronuclei. The male and female pronuclei were apposed within 12 h in porcine oocytes following sperm injection from either source. We also introduced foreign mitochondria from either mouse or pig sperm midpiece into porcine oocytes following sperm injection. While porcine sperm mitochondria rapidly disappeared from the actively developing porcine oocytes, mouse sperm mitochondria remained in the embryos until the 8-cell stage. These results suggest that pronuclear formation and movement occur between 6 and 12 h following sperm incorporation into the cytoplasm, and that foreign mitochondria are selectively removed in a species-specific manner.

Chromatin and microtubule organisation in maturing and pre-activated porcine oocytes following intracytoplasmic sperm injection.

Chromatin and microtubule organisation was determined in maturing and activated porcine oocytes following intracytoplasmic sperm injection in order to obtain insights into the nature of sperm chromatin decondensation and microtubule nucleation activity. Sperm chromatin was slightly decondensed at 8 h following injection into germinal vesicle stage oocytes. Sperm-derived microtubules were not seen in these oocytes. Following injection into metaphase I (MI)-stage oocytes, sperm chromatin went to metaphase in most cases. A meiotic-like spindle was seen in the sperm metaphase chromatin. In a few MI-stage oocytes, sperm chromatin decondensed at 8 h after injection, and a small sperm aster was seen. Sperm injection into oocytes at 5 h following activation failed to yield pronuclear formation. Maternally derived microtubules were organised near the female chromatin in these oocytes, and seemed to move condensed male chromatin closer to the female pronucleus. At 18 h after sperm injection into pre-activated oocytes, a condensed sperm nucleus was located in close proximity to the female pronucleus. These results suggest that the sperm nuclear decondensing activity and microtubule nucleation abilities of the male centrosome are cell cycle dependent. In the absence of a functional male centrosome, microtubules of female origin take over the role of microtubule nucleation for nuclear movement.