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991.
992.
Kenan Omurtag Amber Cooper Arnold Bullock Cathy Naughton Valerie Ratts Randall Odem Susan E. Lanzendorf 《PloS one》2013,8(7)
Objective
Determine whether testicular sperm extractions and pregnancy outcomes are influenced by male and female infertility diagnoses, location of surgical center and time to cryopreservation.Patients
One hundred and thirty men undergoing testicular sperm extraction and 76 couples undergoing 123 in vitro fertilization cycles with testicular sperm.Outcome Measures
Successful sperm recovery defined as 1–2 sperm/0.5 mL by diagnosis including obstructive azoospermia (n = 60), non-obstructive azoospermia (n = 39), cancer (n = 14), paralysis (n = 7) and other (n = 10). Obstructive azoospermia was analyzed as congenital absence of the vas deferens (n = 22), vasectomy or failed vasectomy reversal (n = 37) and “other”(n = 1). Sperm recovery was also evaluated by surgical site including infertility clinic (n = 54), hospital operating room (n = 67) and physician’s office (n = 11). Treatment cycles were evaluated for number of oocytes, fertilization, embryo quality, implantation rate and clinical/ongoing pregnancies as related to male diagnosis, female diagnosis, and use of fresh or cryopreserved testicular sperm.Results
Testicular sperm recovery from azoospermic males with all diagnoses was high (70 to 100%) except non-obstructive azoospermia (31%) and was not influenced by distance from surgical center to laboratory. Following in vitro fertilization, rate of fertilization was significantly lower with non-obstructive azoospermia (43%, p = <0.0001) compared to other male diagnoses (66%, p = <0.0001, 59% p = 0.015). No differences were noted in clinical pregnancy rate by male diagnosis; however, the delivery rate per cycle was significantly higher with obstructive azoospermia (38% p = 0.0371) compared to diagnoses of cancer, paralysis or other (16.7%). Women diagnosed with diminished ovarian reserve had a reduced clinical pregnancy rate (7.4% p = 0.007) compared to those with other diagnoses (44%).Conclusion
Testicular sperm extraction is a safe and effective option regardless of the etiology of the azoospermia. The type of surgical center and/or its distance from the laboratory was not related to success. Men with non-obstructive azoospermia have a lower chance of successful sperm retrieval and fertilization. 相似文献993.
Chemical shifts provide not only peak identities for analyzing nuclear magnetic resonance (NMR) data, but also an important source of conformational information for studying protein structures. Current structural studies requiring Hα chemical shifts suffer from the following limitations. (1) For large proteins, the Hα chemical shifts can be difficult to assign using conventional NMR triple-resonance experiments, mainly due to the fast transverse relaxation rate of Cα that restricts the signal sensitivity. (2) Previous chemical shift prediction approaches either require homologous models with high sequence similarity or rely heavily on accurate backbone and side-chain structural coordinates. When neither sequence homologues nor structural coordinates are available, we must resort to other information to predict Hα chemical shifts. Predicting accurate Hα chemical shifts using other obtainable information, such as the chemical shifts of nearby backbone atoms (i.e., adjacent atoms in the sequence), can remedy the above dilemmas, and hence advance NMR-based structural studies of proteins. By specifically exploiting the dependencies on chemical shifts of nearby backbone atoms, we propose a novel machine learning algorithm, called Hash, to predict Hα chemical shifts. Hash combines a new fragment-based chemical shift search approach with a non-parametric regression model, called the generalized additive model, to effectively solve the prediction problem. We demonstrate that the chemical shifts of nearby backbone atoms provide a reliable source of information for predicting accurate Hα chemical shifts. Our testing results on different possible combinations of input data indicate that Hash has a wide rage of potential NMR applications in structural and biological studies of proteins. 相似文献
994.
Holder Peter E. Jeanson Amanda L. Lennox Robert J. Brownscombe Jacob W. Arlinghaus Robert Danylchuk Andy J. Bower Shannon D. Hyder Kieran Hunt Len M. Fenichel Eli P. Venturelli Paul A. Thorstad Eva B. Allen Micheal S. Potts Warren M. Clark-Danylchuk Sascha Claussen Julie E. Lyle Jeremy M. Tsuboi Jun-ichi Brummett Randall Freire Kátia M. F. Tracey Sean R. Skov Christian Cooke Steven J. 《Reviews in Fish Biology and Fisheries》2020,30(1):137-151
Reviews in Fish Biology and Fisheries - Recreational fisheries hold immense ecological, social, and economic value. The management of these fisheries is increasingly important as we move forward in... 相似文献
995.
Mizuri Marutani-Hert Terence J. Evens Gregory T. McCollum Randall P. Niedz 《Plant Cell, Tissue and Organ Culture》2011,106(1):81-91
Bud emergence and shoot growth from adult phase citrus nodal cultures were studied using Citrus mitis (calamondin), Citrus paradisi (grapefruit), and Citrus sinensis (sweet orange). The effects of 6-benzyladenine (BA), indole 3-acetic acid (IAA), and citrus type on shoot quality and growth of mature bud explants from greenhouse grown trees were determined using a 2-component mixture-amount × citrus type experiment. BA increased shoot number and IAA improved shoot growth. The best shoot quality (fewer shoots but large shoots) was obtained with 1 μM IAA for calamondin, 15.5 μM IAA for sweet orange, and 30 μM IAA for grapefruit. Grapefruit exhibited substantial leaf abscission compared to calamondin and sweet orange. Four factors (AgNO3, silver thiosulphate (STS), CaNO3, or gelling) were screened individually for their efficacy in reducing leaf abscission. Five factors (AgNO3, gelling, MS ion concentration, plant growth regulator and venting) were investigated to identify potential combinations for reducing leaf abscission and maximizing shoot growth and bud emergence. The factor combination identified as most effective in minimizing leaf drop, promoting shoot growth, and maximizing bud emergence for grapefruit was 2 mg l?1 AgNO3, Gelrite, 1 × MS ion concentration, 30 μM IAA, and vented. 相似文献
996.
de Kloet AD Krause EG Scott KA Foster MT Herman JP Sakai RR Seeley RJ Woods SC 《American journal of physiology. Endocrinology and metabolism》2011,301(6):E1081-E1091
Considerable evidence implicates the renin-angiotensin system (RAS) in the regulation of energy balance. To evaluate the role of the RAS in the central nervous system regulation of energy balance, we used osmotic minipumps to chronically administer angiotensin II (Ang II; icv; 0.7 ng/min for 24 days) to adult male Long-Evans rats, resulting in reduced food intake, body weight gain, and adiposity. The decrease in body weight and adiposity occurred relative to both ad libitum- and pair-fed controls, implying that reduced food intake in and of itself does not underlie all of these effects. Consistent with this, rats administered Ang II had increased whole body heat production and oxygen consumption. Additionally, chronic icv Ang II increased uncoupling protein-1 and β(3)-adrenergic receptor expression in brown adipose tissue and β3-adrenergic receptor expression in white adipose tissue, which is suggestive of enhanced sympathetic activation and thermogenesis. Chronic icv Ang II also increased hypothalamic agouti-related peptide and decreased hypothalamic proopiomelanocortin expression, consistent with a state of energy deficit. Moreover, chronic icv Ang II increased the anorectic corticotrophin- and thyroid-releasing hormones within the hypothalamus. These results suggest that Ang II acts in the brain to promote negative energy balance and that contributing mechanisms include an alteration in the hypothalamic circuits regulating energy balance, a decrease in food intake, an increase in energy expenditure, and an increase in sympathetic activation of brown and white adipose tissue. 相似文献
997.
CPT (carnitine palmitoyltransferase) 1 and CPT2 regulate fatty acid oxidation. Recombinant rat CPT2 was isolated from the soluble fractions of bacterial extracts and expressed in Escherichia coli. The acyl-CoA chain-length-specificity of the recombinant CPT2 was identical with that of the purified enzyme from rat liver mitochondrial inner membranes. The Km for carnitine for both the mitochondrial preparation and the recombinant enzyme was identical. In isolated mitochondrial outer membranes, cardiolipin (diphosphatidylglycerol) increased CPT1 activity 4-fold and the Km for carnitine 6-fold. It decreased the Ki for malonyl-CoA inhibition 60-fold, but had no effect on the apparent Km for myristoyl-CoA. Cardiolipin also activated recombinant CPT2 almost 4-fold, whereas phosphatidylglycerol, phosphatidylserine and phosphatidylcholine activated the enzyme 3-, 2- and 2-fold respectively. Most of the recombinant CPT2 was found to have substantial interaction with cardiolipin. A model is proposed whereby cardiolipin may hold the fatty-acid-oxidizing enzymes in the active functional conformation between the mitochondrial inner and outer membranes in conjunction with the translocase and the acyl-CoA synthetase, thus combining all four enzymes into a functional unit. 相似文献
998.
Jiang TX Tuan TL Wu P Widelitz RB Chuong CM 《Differentiation; research in biological diversity》2011,81(5):307-314
Organogenesis involves a series of dynamic morphogenesis and remodeling processes. Since feathers exhibit complex forms, we have been using the feather as a model to analyze how molecular pathways and cellular events are used. While several major molecular pathways have been studied, the roles of matrix degrading proteases and inhibitors in feather morphogenesis are unknown. Here we addressed this knowledge gap by studying the temporal and spatial expression of proteases and inhibitors in developing feathers using mammalian antibodies that cross react with chicken proteins. We also investigated the effect of protease inhibitors on feather development employing an in vitro feather bud culture system. The results show that antibodies specific for mammalian MMP2 and TIMP2 stained positive in both feather epithelium and mesenchyme. The staining co-localized in structures of E10-E13 developing feathers. Interestingly, MMP2 and TIMP2 exhibited a complementary staining pattern in developing E15 and E20 feathers and in maturing feather filaments. Although they exhibited a slight delay in feather bud development, similar patterns of MMP2 and TIMP2 staining were observed in in vitro culture explants. The broad spectrum pharmacological inhibitors AG3340 and BB103 (MMP inhibitors) but not Aprotinin (a plasmin inhibitor) showed a reversible effect on epithelium invagination and feather bud elongation. TIMP2, a physiological inhibitor to MMPs, exhibited a similar effect. Markers of feather morphogenesis showed that MMP activity was required for both epithelium invagination and mesenchymal cell proliferation. Inhibition of MMP activity led to an overall delay in the expression of molecules that regulate either early feather bud growth and/or differentiation and thereby produced abnormal buds with incomplete follicle formation. This work demonstrates that MMPs and their inhibitors are not only important in injury repair, but also in development tissue remodeling as demonstrated here for the formation of feather follicles. 相似文献
999.
Spencer CT Byrne BJ Bryant RM Margossian R Maisenbacher M Breitenger P Benni PB Redfearn S Marcus E Cade WT 《American journal of physiology. Heart and circulatory physiology》2011,301(5):H2122-H2129
Barth syndrome (BTHS) is a mitochondrial myopathy characterized by reports of exercise intolerance. We sought to determine if 1) BTHS leads to abnormalities of skeletal muscle O(2) extraction/utilization and 2) exercise intolerance in BTHS is related to impaired O(2) extraction/utilization, impaired cardiac function, or both. Participants with BTHS (age: 17 ± 5 yr, n = 15) and control participants (age: 13 ± 4 yr, n = 9) underwent graded exercise testing on a cycle ergometer with continuous ECG and metabolic measurements. Echocardiography was performed at rest and at peak exercise. Near-infrared spectroscopy of the vastus lateralis muscle was continuously recorded for measurements of skeletal muscle O(2) extraction. Adjusting for age, peak O(2) consumption (16.5 ± 4.0 vs. 39.5 ± 12.3 ml·kg(-1)·min(-1), P < 0.001) and peak work rate (58 ± 19 vs. 166 ± 60 W, P < 0.001) were significantly lower in BTHS than control participants. The percent increase from rest to peak exercise in ejection fraction (BTHS: 3 ± 10 vs. control: 19 ± 4%, P < 0.01) was blunted in BTHS compared with control participants. The muscle tissue O(2) saturation change from rest to peak exercise was paradoxically opposite (BTHS: 8 ± 16 vs. control: -5 ± 9, P < 0.01), and the deoxyhemoglobin change was blunted (BTHS: 0 ± 12 vs. control: 10 ± 8, P < 0.09) in BTHS compared with control participants, indicating impaired skeletal muscle extraction in BTHS. In conclusion, severe exercise intolerance in BTHS is due to both cardiac and skeletal muscle impairments that are consistent with cardiac and skeletal mitochondrial myopathy. These findings provide further insight to the pathophysiology of BTHS. 相似文献
1000.
Holliday CJ Ankeny RF Jo H Nerem RM 《American journal of physiology. Heart and circulatory physiology》2011,301(3):H856-H867
The role of endothelial cells (ECs) in aortic valve (AV) disease remains relatively unknown; however, disease preferentially occurs in the fibrosa. We hypothesized oscillatory shear (OS) present on the fibrosa stimulates ECs to modify mRNAs and microRNAs (miRNAs) inducing disease. Our goal was to identify mRNAs and miRNAs differentially regulated by OS and laminar shear (LS) in human AVECs (HAVECs) from the fibrosa (fHAVECs) and ventricularis (vHAVECs). HAVECs expressed EC markers as well as some smooth muscle cell markers and functionally aligned with the flow. HAVECs were exposed to OS and LS for 24 h, and total RNA was analyzed by mRNA and miRNA microarrays. We found over 700 and 300 mRNAs down- and upregulated, respectively, by OS; however, there was no side dependency. mRNA microarray results were validated for 26 of 28 tested genes. Ingenuity Pathway Analysis revealed thrombospondin 1 (Thbs1) and NF-κB inhibitor-α (Nfkbia) as highly connected, shear-sensitive genes. miRNA array analysis yielded 30 shear-sensitive miRNAs and 3 side-specific miRNAs. miRNA validation confirmed 4 of 17 shear-sensitive miRNAs and 1 of 3 side-dependent miRNAs. Using miRWalk and several filtering steps, we identified shear-sensitive mRNAs potentially targeted by shear-sensitive miRNAs. These genes and signaling pathways could act as therapeutic targets of AV disease. 相似文献