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101.
Background
Fibroblast Growth Factors (FGFs) represent a large family of secreted proteins that are required for proper development and physiological processes. Mutations in mouse and zebrafish FGFs result in abnormal embryogenesis and lethality. A key to understanding the precise role for these factors is to determine their spatial and temporal activity during embryogenesis. 相似文献102.
Paulo FP Pimenta Alessandra S Orfano Ana C Bahia Ana PM Duarte Claudia M Ríos-Velásquez Fabrício F Melo Felipe AC Pessoa Giselle A Oliveira Keillen MM Campos Luis Martínez Villegas Nilton Barnabé Rodrigues Rafael Nacif-Pimenta Rejane C Sim?es Wuelton M Monteiro Rogerio Amino Yara M Traub-Cseko José BP Lima Maria GV Barbosa Marcus VG Lacerda Wanderli P Tadei Nágila FC Secundino 《Memórias do Instituto Oswaldo Cruz》2015,110(1):23-47
In the Americas, areas with a high risk of malaria transmission are mainly located in
the Amazon Forest, which extends across nine countries. One keystone step to
understanding the Plasmodium life cycle in Anopheles species from the Amazon Region
is to obtain experimentally infected mosquito vectors. Several attempts to colonise
Ano- pheles species have been conducted, but with only short-lived success or no
success at all. In this review, we review the literature on malaria transmission from
the perspective of its Amazon vectors. Currently, it is possible to develop
experimental Plasmodium vivax infection of the colonised and field-captured vectors
in laboratories located close to Amazonian endemic areas. We are also reviewing
studies related to the immune response to P. vivax infection of Anopheles aquasalis,
a coastal mosquito species. Finally, we discuss the importance of the modulation of
Plasmodium infection by the vector microbiota and also consider the anopheline
genomes. The establishment of experimental mosquito infections with Plasmodium
falciparum, Plasmodium yoelii and Plasmodium berghei parasites that could provide
interesting models for studying malaria in the Amazonian scenario is important.
Understanding the molecular mechanisms involved in the development of the parasites
in New World vectors is crucial in order to better determine the interaction process
and vectorial competence. 相似文献
103.
104.
A role for the FtsQLB complex in cytokinetic ring activation revealed by an ftsL allele that accelerates division 下载免费PDF全文
The cytokinetic apparatus of bacteria is initially formed by the polymerization of the tubulin‐like FtsZ protein into a ring structure at midcell. This so‐called Z‐ring facilitates the recruitment of many additional proteins to the division site to form the mature divisome machine. Although the assembly pathway leading to divisome formation has been well characterized, the mechanisms that trigger cell constriction remain unclear. In this report, we study a ‘forgotten’ allele of ftsL from Escherichia coli, which encodes a conserved division gene of unknown function. We discovered that this allele promotes the premature initiation of cell division. Further analysis also revealed that the mutant bypasses the requirement for the essential division proteins ZipA, FtsK and FtsN, and partially bypasses the need for FtsA. These findings suggest that rather than serving simply as a protein scaffold within the divisome, FtsL may play a more active role in the activation of the machine. Our results support a model in which FtsL, along with its partners FtsB and FtsQ, function as part of a sensing mechanism that promotes the onset of cell wall remodeling processes needed for the initiation of cell constriction once assembly of the divisome complex is deemed complete. 相似文献
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Salinthone S Schillace RV Tsang C Regan JW Bourdette DN Carr DW 《The Journal of nutritional biochemistry》2011,22(7):681-690
Lipoic acid (LA) is a naturally occurring fatty acid that exhibits anti-oxidant and anti-inflammatory properties and is being pursued as a therapeutic for many diseases including multiple sclerosis, diabetic polyneuropathy and Alzheimer's disease. We previously reported on the novel finding that racemic LA (50:50 mixture of R-LA and S-LA) stimulates cAMP production, activates prostanoid EP2 and EP4 receptors and adenylyl cyclases (AC), and suppresses activation and cytotoxicity in NK cells. In this study, we present evidence that furthers our understanding of the mechanisms of action of LA. Using various LA derivatives, such as dihydrolipoic acid (DHLA), S,S-dimethyl lipoic acid (DMLA) and lipoamide (LPM), we discovered that only LA is capable of stimulating cAMP production in NK cells. Furthermore, there is no difference in cAMP production after stimulation with either R-LA, S-LA or racemic LA. Competition and synergistic studies indicate that LA may also activate AC independent of the EP2 and EP4 receptors. Pretreatment of PBMCs with KH7 (a specific peptide inhibitor of soluble AC) and the calcium inhibitor (Bapta) prior to LA treatment resulted in reduced cAMP levels, suggesting that soluble AC and calcium signaling mediate LA stimulation of cAMP production. In addition, pharmacological inhibitor studies demonstrate that LA also activates other G protein-coupled receptors, including histamine and adenosine but not the β-adrenergic receptors. These novel findings provide information to better understand the mechanisms of action of LA, which can help facilitate the use of LA as a therapeutic for various diseases. 相似文献
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Shih-Wei Chen Sheng-Huang Lin Lun-De Liao Hsin-Yi Lai Yu-Cheng Pei Te-Son Kuo Chin-Teng Lin Jyh-Yeong Chang You-Yin Chen Yu-Chun Lo Shin-Yuan Chen Robby Wu Siny Tsang 《Biomedical engineering online》2011,10(1):99
Background
The computer-aided identification of specific gait patterns is an important issue in the assessment of Parkinson's disease (PD). In this study, a computer vision-based gait analysis approach is developed to assist the clinical assessments of PD with kernel-based principal component analysis (KPCA).Method
Twelve PD patients and twelve healthy adults with no neurological history or motor disorders within the past six months were recruited and separated according to their "Non-PD", "Drug-On", and "Drug-Off" states. The participants were asked to wear light-colored clothing and perform three walking trials through a corridor decorated with a navy curtain at their natural pace. The participants' gait performance during the steady-state walking period was captured by a digital camera for gait analysis. The collected walking image frames were then transformed into binary silhouettes for noise reduction and compression. Using the developed KPCA-based method, the features within the binary silhouettes can be extracted to quantitatively determine the gait cycle time, stride length, walking velocity, and cadence.Results and Discussion
The KPCA-based method uses a feature-extraction approach, which was verified to be more effective than traditional image area and principal component analysis (PCA) approaches in classifying "Non-PD" controls and "Drug-Off/On" PD patients. Encouragingly, this method has a high accuracy rate, 80.51%, for recognizing different gaits. Quantitative gait parameters are obtained, and the power spectrums of the patients' gaits are analyzed. We show that that the slow and irregular actions of PD patients during walking tend to transfer some of the power from the main lobe frequency to a lower frequency band. Our results indicate the feasibility of using gait performance to evaluate the motor function of patients with PD.Conclusion
This KPCA-based method requires only a digital camera and a decorated corridor setup. The ease of use and installation of the current method provides clinicians and researchers a low cost solution to monitor the progression of and the treatment to PD. In summary, the proposed method provides an alternative to perform gait analysis for patients with PD.110.
Improving Detection Accuracy of Lung Cancer Serum Proteomic Profiling via Two-Stage Training Process
Hsu PS Wang YS Huang SC Lin YH Chang CC Tsang YW Jiang JS Kao SJ Uen WC Chi KH 《Proteome science》2011,9(1):20