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91.
New series of N-modified analogues of the N/OFQ(1-13)NH(2) with aminophosphonate moiety have been synthesized and investigated for biological activity. These peptides were prepared by solid-phase peptide synthesis-Fmoc-strategy. The N/OFQ(1-13)NH(2) analogues were tested for agonistic activity in vitro on electrically stimulated rat vas deferens smooth-muscle preparations isolated from Wistar albino rats. Our study has shown that the selectivity of the peptides containing 1-[(methoxyphosphono)methylamino]cycloalkanecarboxylic acids to the N-side of Phe is not changed-they remain selective agonists of NOP receptors. The derivative with the largest ring (NOC-6) demonstrated efficacy similar to that of N/OFQ(1-13)NH(2), but in a 10-fold higher concentration. The agonistic activity of newly synthesized N-modified analogues of N/OFQ(1-13)NH(2) with aminophosphonate moiety was investigated for the first time. 相似文献
92.
BACKGROUND: Mutations in the chloride channel gene, CLCNKB, usually cause classic Bartter syndrome (cBS) or a mixed Bartter-Gitelman phenotype in the first years of life. METHODS: We report an adult woman with atypical BS caused by a homozygous missense mutation, A204T, in the CLCNKB gene, which has previously been described as the apparently unique cause of cBS in Spain. RESULTS: The evaluation of this patient revealed an overlap of phenotypic features ranging from severe biochemical and systemic disturbances typical of cBS to scarce symptoms and diagnosis in the adult age typical of Gitelman syndrome. The tubular disease caused a dramatic effect on mental, growth and puberal development leading to low IQ, final short stature and abnormal ovarian function. Furthermore, low serum PTH concentrations with concomitant nephrocalcinosis and normocalcaemia were observed. Both ovarian function and serum PTH levels were normalized after treatment with cyclooxygenase inhibitors. CONCLUSIONS: The present report confirms a weak genotype-phenotype correlation in patients with CLCNKB mutations and supports the founder effect of the A204T mutation in Spain. In our country, the genetic diagnosis of adult patients with hereditary hypokalaemic tubulopathies should include a screening of A204T mutation in the CLCNKB gene. 相似文献
93.
This study was done on 65 isolated pelvic bones, These cadavers belonged to adult people of mature and old age, and they had no pathological changes. These measurements were performed on osteological collection of Department of Anatomy Drago Perovi?. Many geometrical parameters of facies auricularis were measured, which we considered important for further studies, simulations of joint's action, transfer calculations of the forces from spine to hip joint. We used paper, which partially adapted to the surface of facies auricularis, so the values are closer to real ones than projection values. The results have shown that the average surface of facies auricularis is 13.46 cm(2). There was no statistical significance found between left and right cadavers. For easier orientation we divided surface of facies auricularis into two parts: vertical and horizontal. Height of the vertical part was 3.99 cm, while the width was 2.05 cm. Height of horizontal part was 2.07 cm and the width 3.62 cm. 相似文献
94.
95.
Ralf Janssen Bo Joakim Eriksson Graham E. Budd Michael Akam Nikola‐Michael Prpic 《Evolution & development》2010,12(4):363-372
SUMMARY In arthropods, such as Drosophila melanogaster, the leg gap genes homothorax (hth), extradenticle (exd), dachshund (dac), and Distal‐less (Dll) regionalize the legs in order to facilitate the subsequent segmentation of the legs. We have isolated homologs of all four leg gap genes from the onychophoran Euperipatoides kanangrensis and have studied their expression. We show that leg regionalization takes place in the legs of onychophorans even though they represent simple and nonsegmented appendages. This implies that leg regionalization evolved for a different function and was only later co‐opted for a role in leg segmentation. We also show that the leg gap gene patterns in onychophorans (especially of hth and exd) are similar to the patterns in crustaceans and insects, suggesting that this is the plesiomorphic state in arthropods. The reversed hth and exd patterns in chelicerates and myriapods are therefore an apomorphy for this group, the Myriochelata, lending support to the Myriochelata and Tetraconata clades in arthropod phylogeny. 相似文献
96.
Cadherin-mediated specific cell adhesion is an important process in brain development as well as in synaptic plasticity in the adult brain. In this study the authors quantified mRNA levels of N-cadherin and cadherin-11 in different brain regions for the first time. In hippocampus N-cadherin mRNA levels were very high at embryonic stages and decreased during further development, whereas cadherin-11 mRNA levels were highest at postnatal stages. However, N-cadherin protein level was not altered during hippocampal development and cadherin-11 protein was low at embryonic but high at postnatal and adult stages. In cultured hippocampal neurons both cadherins became colocalized and recruited to synaptic sites during ongoing differentiation, with especially high accumulation of cadherin-11 at synapses. These data hint at a critical role of N-cadherin at early embryonic stages and early synaptogenesis, whereas cadherin-11 might be more important for further stabilization of synapses in the postnatal period and adulthood. 相似文献
97.
Shen Y Tolić N Liu T Zhao R Petritis BO Gritsenko MA Camp DG Moore RJ Purvine SO Esteva FJ Smith RD 《PloS one》2010,5(10):e13133
Background
Cancer invasion and metastasis are closely associated with activities within the degradome; however, little is known about whether these activities can be detected in the blood of cancer patients.Methodology and Principal Findings
The peptidome-degradome profiles of pooled blood plasma sampled from 15 breast cancer patients (BCP) and age, race, and menopausal status matched control healthy persons (HP) were globally characterized using advanced comprehensive separations combined with tandem Fourier transform mass spectrometry and new data analysis approaches that facilitated top-down peptidomic analysis. The BCP pool displayed 71 degradome protein substrates that encompassed 839 distinct peptidome peptides. In contrast, the HP 50 degradome substrates found encompassed 425 peptides. We find that the ratios of the peptidome peptide relative abundances can vary as much as >4000 fold between BCP and HP. The experimental results also show differential degradation of substrates in the BCP sample in their functional domains, including the proteolytic and inhibitory sites of the plasmin-antiplasmin and thrombin-antithrombin systems, the main chains of the extracellular matrix protection proteins, the excessive degradation of innate immune system key convertases and membrane attack complex components, as well as several other cancer suppressor proteins.Conclusions
Degradomics-peptidomics profiling of blood plasma is highly sensitive to changes not evidenced by conventional bottom-up proteomics and potentially provides unique signatures of possible diagnostic utility. 相似文献98.
On March 11, 2020 the World Health Organization classified COVID-19, caused by Sars-CoV-2, as a pandemic. Although not much was known about the new virus, the first outbreaks in China and Italy showed that potentially a large number of people worldwide could fall critically ill in a short period of time. A shortage of ventilators and intensive care resources was expected in many countries, leading to concerns about restrictions of medical care and preventable deaths. In order to be prepared for this challenging situation, national triage guidance has been developed or adapted from former influenza pandemic guidelines in an increasing number of countries over the past few months. In this article, we provide a comparative analysis of triage recommendations from selected national and international professional societies, including Australia/New Zealand, Belgium, Canada, Germany, Great Britain, Italy, Pakistan, South Africa, Switzerland, the United States, and the International Society of Critical Care Medicine. We describe areas of consensus, including the importance of prognosis, patient will, transparency of the decision-making process, and psychosocial support for staff, as well as the role of justice and benefit maximization as core principles. We then probe areas of disagreement, such as the role of survival versus outcome, long-term versus short-term prognosis, the use of age and comorbidities as triage criteria, priority groups and potential tiebreakers such as ‘lottery’ or ‘first come, first served’. Having explored a number of tensions in current guidance, we conclude with a suggestion for framework conditions that are clear, consistent and implementable. This analysis is intended to advance the ongoing debate regarding the fair allocation of limited resources and may be relevant for future policy-making. 相似文献
99.
Kuzmic Nikola Moore Thomas Devadas Deepika Young Edmond W. K. 《Biomechanics and modeling in mechanobiology》2019,18(3):717-731
Biomechanics and Modeling in Mechanobiology - Tumour-induced angiogenesis is a complex biological process that involves growth of new blood vessels within the tumour microenvironment and is an... 相似文献
100.
The SCF ubiquitin ligases catalyze protein ubiquitination in diverse cellular processes. SCFs bind substrates through the interchangeable F box protein subunit, with the >70 human F box proteins allowing the recognition of a wide range of substrates. The F box protein beta-TrCP1 recognizes the doubly phosphorylated DpSGphiXpS destruction motif, present in beta-catenin and IkappaB, and directs the SCF(beta-TrCP1) to ubiquitinate these proteins at specific lysines. The 3.0 A structure of a beta-TrCP1-Skp1-beta-catenin complex reveals the basis of substrate recognition by the beta-TrCP1 WD40 domain. The structure, together with the previous SCF(Skp2) structure, leads to the model of SCF catalyzing ubiquitination by increasing the effective concentration of the substrate lysine at the E2 active site. The model's prediction that the lysine-destruction motif spacing is a determinant of ubiquitination efficiency is confirmed by measuring ubiquitination rates of mutant beta-catenin peptides, solidifying the model and also providing a mechanistic basis for lysine selection. 相似文献