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1.
Restriction maps of the rDNA cistron of twelve species of mosquitoes in six genera of the subfamily Culicinae were constructed using eight 6 bp recognition restriction enzymes. Anopheles albimanus was used as an outgroup. The size of the rDNA cistron ranged from 8.5 kb in Aedes katherinensis to 12.9 kb in Ae. polynesiensis. A total of twenty-six sites were scored; eighteen were polymorphic among ingroup taxa. The proportion of polymorphic nucleotide sites (Pnuc) was 0.059 and the heterozygosity per nucleotide site (Hnuc) was 0.028. Wagner and Fitch Parsimony, Dollo Parsimony and Nei-Li distance/neighbour-joining methods were used to construct phylogenetic trees. The rDNA RFLP dataset did not provide a well-supported phylogeny among culicine taxa. The RFLP phylogenies are incongruent with the morphology character based and molecular phylogenies and derived relationships did not correspond with current taxonomic classifications. The lack of resolution was due to homoplasy arising from frequent independent loss or gain of restriction sites among unrelated taxa.  相似文献   
2.
INTRODUCTION: Cardiopulmonary bypass (CPB) induces an inflammatory response believed to contribute to postoperative morbidity. We hypothesized that the magnitude of the inflammatory response following CPB would be associated with adverse clinical outcomes. METHODS: Twenty-nine patients had plasma TNF, IL-6, IL-8, elastase, histamine, complement C5a, and complement C3a measured by ELISA before, during, and after cardiac operations employing CPB. Inflammatory mediator levels were analyzed with respect to outcomes. RESULTS: Mediator levels peaked at 4 h post-CPB and either returned to baseline or substantially decreased by 24 h. Patients with peak mediator levels above the median for the group as a whole were classified as 'hyper-responders'; those with levels below the median were classified as 'normal responders'. While IL-8, C3a, and IL-6 levels were independently associated with adverse outcomes, TNF, histamine, and C5a levels were not. Elastase levels trended towards adverse outcomes. IL-8 'hyper-responders' experienced significantly greater postoperative weight gain and had higher IL-8 levels at 24 h (p<0.05), with trends towards renal impairment and protracted supplemental oxygen requirements. C3a 'hyper-responders' strongly trended towards increased bleeding, delayed extubation, greater postoperative weight gain, and decreased levels of independent functioning at discharge (p < or = 0.10). IL-6 'hyper-responders' experienced significantly more postoperative bleeding, delayed extubation, and higher IL-6 levels at 24 h compared to 'normal responders' (p < 0.05). They strongly trended towards greater postoperative weight gain and decreased levels of independent functioning at discharge (p < or = 0.10). CONCLUSIONS: Patients who have an exaggerated inflammatory response to CPB tend to bleed more, require more respiratory support, demonstrate greater capillary leak via weight gain, and display a decline in independent functioning relative to normal responders. Thus, it appears that the magnitude of the inflammatory response to CPB adversely influences clinical outcomes.  相似文献   
3.
Tryptophan hydroxylase (TPH) catalyzes the rate-limiting step in the biosynthesis of serotonin. In the rabbit, TPH exists as a tetramer of four identical 51-kDa subunits comprised of 444 amino acids each. The enzyme consists of an amino-terminal regulatory domain and a carboxyl-terminal catalytic domain. Previous studies demonstrated that within the carboxyl-terminus of TPH, there resides an intersubunit binding domain (a leucine zipper) that is essential for tetramer formation. However, it is hypothesized that a 4,3-hydrophobic repeat identified within the regulatory domain of TPH (residues 21–41) may also be involved in macromolecular assembly. To test this hypothesis, a series of amino-terminal deletions (NΔ15, 30, 41, and 90) were created and assessed for macromolecular structure using size-exclusion chromatography. The amino-terminal deletion NΔ15, upstream from the 4,3-hydrophobic repeat, was capable of forming tetramers. However, when a portion of the 4,3-hydrophobic repeat was deleted (NΔ30), a heterogeneous elution pattern of tetramers, dimers, and monomers was observed. Complete removal of the 4,3-hydrophobic repeat (NΔ41) rendered the enzyme incapable of forming tetramers; a monomeric form predominated. In addition, a double-point mutation (V28R-L31R) was created in the hydrophobic region of the enzyme. The introduction of two arginines (R) at positions 28 and 31 respectively, in the helix disrupted the native tetrameric state of TPH. According to size-exclusion chromatography analysis, the double-point mutant (V28R-L31R) formed dimers of 127 kDa. Thus, it is concluded that there is information within the amino-terminus that is necessary for tetramer formation of TPH. This additional intersubunit binding domain in the amino-terminus is similar to that found in the carboxyl-terminus.  相似文献   
4.

Background

Ovarian adenocarcinoma is not generally discovered in patients until there has been widespread intraperitoneal dissemination, which is why ovarian cancer is the deadliest gynecologic malignancy. Though incompletely understood, the mechanism of peritoneal metastasis relies on primary tumor cells being able to detach themselves from the tumor, escape normal apoptotic pathways while free floating, and adhere to, and eventually invade through, the peritoneal surface. Our laboratory has previously shown that the Golgi glycosyltransferase, ST6Gal-I, mediates the hypersialylation of β1 integrins in colon adenocarcinoma, which leads to a more metastatic tumor cell phenotype. Interestingly, ST6Gal-I mRNA is known to be upregulated in metastatic ovarian cancer, therefore the goal of the present study was to determine whether ST6Gal-I confers a similarly aggressive phenotype to ovarian tumor cells.

Methods

Three ovarian carcinoma cell lines were screened for ST6Gal-I expression, and two of these, PA-1 and SKOV3, were found to produce ST6Gal-I protein. The third cell line, OV4, lacked endogenous ST6Gal-I. In order to understand the effects of ST6Gal-I on cell behavior, OV4 cells were stably-transduced with ST6Gal-I using a lentiviral vector, and integrin-mediated responses were compared in parental and ST6Gal-I-expressing cells.

Results

Forced expression of ST6Gal-I in OV4 cells, resulting in sialylation of β1 integrins, induced greater cell adhesion to, and migration toward, collagen I. Similarly, ST6Gal-I expressing cells were more invasive through Matrigel.

Conclusion

ST6Gal-I mediated sialylation of β1 integrins in ovarian cancer cells may contribute to peritoneal metastasis by altering tumor cell adhesion and migration through extracellular matrix.  相似文献   
5.
6.
We analyzed peri-operative outcomes of 80 patients who underwent robotic-assisted laparoscopic surgery and were diagnosed with stage IV endometriosis (revised American Society for Reproductive Medicine) between January 2007 and December 2010 at a tertiary gynecologic oncology referral center with a fellowship training program. Eligible women had a combination of one or more factors: pelvic mass, sub-acute or chronic pelvic pain, dysmenorrhea, dyspareunia, elevated serum CA-125, diagnosed with stage IV endometriosis at surgery with robotic-assisted gynecologic procedures using the da Vinci? Surgical System. The mean age was 43.7?±?7.0?years, body mass index 27.5?±?7.4?kg/m2, and 23 (28.9%) patients had prior endometriosis surgery. Presenting symptoms included: chronic pelvic pain (48.8%), dysmenorrhea (40.3%), and dyspareunia (33.8%). Sixty-nine (86%) patients had pelvic masses (43 unilateral and 26 bilateral). Thirty-seven (46.3%) had elevated CA-125 levels (mean 97.9?±?71.6 U/ml). Forty-eight (60%) underwent robotic-assisted laparoscopic hysterectomy (RALH)/bilateral salpingo-oophorectomy (BSO), 9 (11.3%) RALH/unilateral salpingo-oophorectomy (USO), 5 (6.3%) modified radical hysterectomy, and 10 (13%) USO or BSO only. Four (5%) had ovarian cystectomies with excision of endometriotic implants. Three (3.8%) underwent appendectomy and no patient required bowel resection. Four (5%) patients required conversion to laparotomy during the first 15 cases of this series [dense adhesions (3) and ureteral injury (1)]. Mean operative time was 115?±?46?min, blood loss 88?±?67?ml, and length of stay 1.0?±?0.4?days. There were four (5%) complications (ureteral injury, cuff abscess, cuff hematoma, re-admission for nausea and vomiting secondary to narcotics) and no transfusions. One (1.3%) patient underwent a second surgery for pain (dyspareunia). Robotic-assisted surgery for stage IV endometriosis resulted in excellent pain relief, with few laparotomy conversions or complications during a robotic learning-curve experience.  相似文献   
7.
8.
A percentage of either measured or predicted maximum heart rate is commonly used to prescribe and measure exercise intensity. However, maximum heart rate in athletes may be greater during competition or training than during laboratory exercise testing. Thus, the aim of the present investigation was to determine if endurance-trained runners train and compete at or above laboratory measures of ''maximum'' heart rate. Maximum heart rates were measured utilising a treadmill graded exercise test (GXT) in a laboratory setting using 10 female and 10 male National Collegiate Athletic Association (NCAA) division 2 cross-country and distance event track athletes. Maximum training and competition heart rates were measured during a high-intensity interval training day (TR HR) and during competition (COMP HR) at an NCAA meet. TR HR (207 ± 5.0 b·min-1; means ± SEM) and COMP HR (206 ± 4 b·min-1) were significantly (p < 0.05) higher than maximum heart rates obtained during the GXT (194 ± 2 b·min-1). The heart rate at the ventilatory threshold measured in the laboratory occurred at 83.3 ± 2.5% of the heart rate at VO2 max with no differences between the men and women. However, the heart rate at the ventilatory threshold measured in the laboratory was only 77% of the maximal COMP HR or TR HR. In order to optimize training-induced adaptation, training intensity for NCAA division 2 distance event runners should not be based on laboratory assessment of maximum heart rate, but instead on maximum heart rate obtained either during training or during competition.

Key points

  • A percentage of maximum heart rate is commonly used to prescribe and measure exercise intensity. However, maximum heart rate may be greater during competition or training than during laboratory exercise testing.
  • Heart rates during training and competition were significantly higher than maximum heart rates obtained during laboratory exercise testing.
  • To optimize training-induced adaptation, training intensity for NCAA division 2 distance event runners should not be based on laboratory assessment of maximum heart rate, but instead on maximum heart rate measure obtained either during training or during competition.
Key words: Competition, heart rate, laboratory, performance, running, training  相似文献   
9.
Background Information on experience in bariatric surgery in the Asia-Pacific region is minimal: hence the need for more reports from this area. Methods The procedures of bariatric surgery and outcome as part of a weight management program in a tertiary care private hospital in the Philippines is reported from years 2002 to 2004. 50 patients were included, of which 60% underwent laparoscopic adjustable gastric banding (LAGB) and 40% Roux-en- Y gastric bypass (RYGBP). Results There were more females than males (64% vs 36%) with the mean age 38 ± 13.1 years. Initial mean BMI was 46.2 kg/m2, which decreased to 27.0 kg/m2 in 1 year. Initial mean weight was 126.7 ± 25.4 kg, of which the 1 year weight loss was 32.3 kg for the morbidly obese and 58.0 kg for the super obese. %EWL at 1 year was 30.2%. There was greater weight loss with RYGBP compared to LAGB at 1 year (43.5 kg vs 30.2 kg). There was no mortality, and early complications were: wound infection (2/50 or 4%), and 1/50 or 2% each for pneumonia, dehydration, gastritis, and leakage. Late complications were: band slippage (2/20 or 10%), stomal stenosis (1/20 or 5%), and ventral hernia (1/5 or 20%). Conclusion Bariatric surgery is safe with a low complication rate and the outcome was similar to the reported data from Asia and the western world.  相似文献   
10.
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