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1.
Autophosphorylation-independent and -dependent Functions of Focal Adhesion Kinase during Development
Jean-Marc Corsi Christophe Houbron Pierre Billuart Isabelle Brunet Karine Bouvr��e Anne Eichmann Jean-Antoine Girault Herv�� Enslen 《The Journal of biological chemistry》2009,284(50):34769-34776
Focal adhesion kinase (FAK) regulates numerous cellular functions and is critical for processes ranging from embryo development to cancer progression. Although autophosphorylation on Tyr-397 appears required for FAK functions in vitro, its role in vivo has not been established. We addressed this question using a mutant mouse (fakΔ) deleted of exon 15, which encodes Tyr-397. The resulting mutant protein FAKΔ is an active kinase expressed at normal levels. Our results demonstrate that the requirement for FAK autophosphorylation varies during development. FAKΔ/Δ embryos developed normally up to embryonic day (E) 12.5, contrasting with the lethality at E8.5 of FAK-null embryos. Thus, autophosphorylation on Tyr-397 is not required for FAK to achieve its functions until late mid-gestation. However, FAKΔ/Δ embryos displayed hemorrhages, edema, delayed artery formation, vascular remodeling defects, multiple organ abnormalities, and overall developmental retardation at E13.5–14.5, and died thereafter demonstrating that FAK autophosphorylation is also necessary for normal development. Fibroblasts derived from mutant embryos had a normal stellate morphology and expression of focal adhesion proteins, Src family members, p53, and Pyk2. In contrast, in FAKΔ/Δ fibroblasts and endothelial cells, spreading and lamellipodia formation were altered with an increased size and number of focal adhesions, enriched in FAKΔ. FAK mutation also decreased fibroblast proliferation. These results show that the physiological functions of FAK in vivo are achieved through both autophosphorylation-independent and autophosphorylation-dependent mechanisms. 相似文献
2.
Abstract The genus Allium L. in Italy. IV. A DNA cytophotometric study on the pollen grain of Allium chamaemoly L. — A cytophotometric analysis of DNA contents in pollen generative and vegetative nuclei of Allium chamaemoly L. was carried out. DNA synthesis in both nuclei was confirmed and a lightly higher DNA amount than 2C in the vegetative nucleus was pointed out. An analysis of the Fast-green stainable histones in the generative and vegetative nuclei was also accomplished. While the generative nucleus had a very high content of Fast-green stainable histone, the vegetative one have nearly no stainable histone. The occurrence of DNA synthesis and the very low histone content suggest the vegetative nucleus is functional and biochemically activ. The higher than 2C DNA content supports the possibility of a DNA amplification process including probably the amplification of ribosomal cistrons in the pollen vegetative nucleus. 相似文献
3.
4.
Thiago Corsi Filiponi Lúcio Roberto Requi?o-Moura Eduardo José Tonato Ana Cristina Carvalho de Matos Alvaro Pacheco e Silva-Filho Marcelino de Souza Dur?o Junior 《PloS one》2015,10(9)
The incidence and outcomes of acute kidney injury (AKI) in kidney transplantation are poorly known. Retrospective cohort analysis was performed on the data of all patients (≥3 months after transplantation and ≥16 years of age) admitted to the hospital due to medical or surgical complications from 2007 to 2010. We analyzed 458 kidney transplant recipients, 55.2% men, median age 49 (IQR, 36–58) years, median of 12.5 (IQR, 3–35) months after kidney transplantation; admitted to the hospital due to medical or surgical complications. Most of the patients received a kidney from a deceased donor (62.2%), the primary cause for hospital admission was infection (60.7%) and 57 (12.4%) individuals were diagnosed with acute rejection (AR). The incidence of AKI was 82.3%: 31.9% stage 1, 29.3% stage 2 and 21.2% stage 3. Intensive care unit (ICU) admission (OR 8.90, 95% CI: 1.77–44.56 p = 0.008), infection (OR 5.73, 95% CI: 2.61–12.56, p<0.001) and the use of contrast media (OR 9.34, 95% CI: 2.04–42.70, p = 0.004) were the independent risk factors for AKI development. The mortality rate was 2.1% and all patients who died were diagnosed with AKI. Even after the exclusion of AR cases, at the end of 12 months, the individuals with AKI exhibited higher percent changes in creatinine values when compared with individuals without AKI (9.1% vs. -4.3%; p<0.001). According to KDIGO system, we found a high incidence of AKI among the complications of renal transplantation. As in other scenarios, AKI was associated with renal function loss at 1-year after the hospital discharge. 相似文献
5.
As recently demonstrated, a placebo procedure in motor performance increases force production and changes the excitability of the corticospinal system, by enhancing the amplitude of the motor evoked potentials (MEP) and reducing the duration of the cortical silent period (CSP). However, it is not clear whether these neurophysiological changes are related to the behavioural outcome (increased force) or to a general effect of expectation. To clarify this, we investigated the nocebo effect, in which the induced expectation decreases force production. Two groups of healthy volunteers (experimental and control) performed a motor task by pressing a piston with the right index finger. To induce a nocebo effect in the experimental group, low frequency transcutaneous electrical nerve stimulation (TENS) was applied over the index finger with instructions of its detrimental effects on force. To condition the subjects, the visual feedback on their force level was surreptitiously reduced after TENS. Results showed that the experimental group reduced the force, felt weaker and expected a worse performance than the control group, who was not suggested about TENS. By applying transcranial magnetic stimulation over the primary motor cortex, we found that while MEP amplitude remained stable throughout the procedure in both groups, the CSP duration was shorter in the experimental group after the nocebo procedure. The CSP reduction resembled previous findings on the placebo effect, suggesting that expectation of change in performance diminishes the inhibitory activation of the primary motor cortex, independently of the behavioural outcome. 相似文献
6.
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
7.
8.
Jing Zhou MD Pengfei Wu MM Hongyu Sun MM Hong Zhou BM Yaolei Zhang BM Zhenliang Xiao MD 《Journal of cellular physiology》2020,235(3):2377-2388
This study aimed to examine whether lung tissue extracellular matrix (ECM) hydrogels have protective effects on radiation-induced lung injury (RILI). The cytocompatibility and histocompatibility were tested for the obtained ECM-derived hydrogel. Sprague–Dawley rats were randomly divided into three groups (n = 18): control group (control); rats receiving irradiation and intratracheal injection of normal saline (IR + NS); and rats receiving irradiation and intratracheal injection of lung ECM-derived hydrogel (IR + ECM). The wet/dry weight ratio was used to evaluate the congestion and edema of the lungs. Histopathological analysis of lung tissues was performed using hemotoxylin and eosin staining and Masson's trichrome staining. Immunohistochemical staining and western blot analyses were carried out to determine the expression of epithelial–mesenchymal transition (EMT)-related proteins in lung tissues (E-cadherin, α-smooth muscle actin [α-SMA], and vimentin). In addition, tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1) and interleukin-6 (IL-6), hydroxyproline, malondialdehyde (MDA), and superoxide dismutase (SOD) levels were also evaluated. The ECM-derived hydrogels had good cytocompatibility and histocompatibility. ECM-derived hydrogel treatment improved lung histopathology injury and pulmonary edema. Higher expression of E-cadherin and lower expression of vimentin and α-SMA were found in the IR + ECM group compared with those in the IR + NS group. Hydroxyproline levels were reduced by ECM-derived hydrogel treatment compared with those in the IR + NS group. Obvious increases of TNF-α, IL-6, and TGF-β1 were identified following irradiation. Marked reductions in MDA content and increases in SOD were induced by ECM-derived hydrogel treatment in rats after radiation. ECM-derived hydrogels were shown to protect against RILI, potentially by reducing EMT, inflammation, and oxidative damage. 相似文献
9.
Giuseppe Puddu Luigi Maiorano Alessandra Falcucci Fabio Corsi Luigi Boitani 《Biodiversity and Conservation》2009,18(8):2001-2016
The Corsican red deer, a sub-species of the European red deer endemic to Sardinia and Corsica, was abundant on both islands
at the beginning of 1900. It went extinct in Corsica and reached a minimum of 100 individuals in Sardinia by 1970. Numbers
have recovered in Sardinia with more than 1,000 rutting males now present; in the 1980s the deer was reintroduced to Corsica,
but the Sardinian population remains fragmented. We developed a potential distribution model in Sardinia using Ecological
Niche Factor Analysis. To assess the deer’s protection status we compared the model with the existing and proposed conservation
areas and investigated different conservation scenarios in relation to the expansion of its current range and resilience to
future changes in land use and predicted trends of desertification. According to our results over 70% of Sardinia is unsuitable
to the deer, nevertheless high suitability areas (Mediterranean forests away from main roads) are available throughout the
island, particularly in the south and in the central-eastern part. Existing protected areas do not provide for the conservation
of the deer but public owned forests, where hunting is prohibited, extend some level of protection, and the protected areas
proposed by the Regional administration, if implemented, will be increasing this protection. Three main areas have emerged
as conservation priorities to guarantee adequate conservation potential in the future. Our approach provides valuable data
to inform conservation policy, and could be easily replicated in other parts of the Mediterranean. 相似文献
10.
G Bronzetti A Galli C Corsi E Cundari R Del Carratore R Nieri M Paolini 《Mutation research》1984,141(1):19-22
Chloral hydrate (CH), a metabolite of trichloroethylene (TCE), was studied in vitro using the D7 diploid strain of Saccharomyces cerevisiae, with and without a mammalian microsomal activation system (S9 fraction), and in vivo by intrasanguineous host-mediated assay (HMA). The in vivo effects on the hepatic microsomal monooxygenase induced by CH in mice pretreated with beta-naphthoflavone (beta-NF) and Naphenobarbital (PB) were also investigated. Chloral hydrate induced a significant increase of mitotic gene conversion in D7 strain both in vivo and in vitro. The enzymatic determinations in mice showed a decrease in aminopyrine N-demethylase (APD) and p-nitroanisole O-demethylase (p-NAD) activities (about 37% and 29% respectively) after one acute dose of CH. Moreover, stability experiments, carried out in the conditions of the liver microsomal assay (LMA), showed an increase of residual activity, after 1 h of preincubation with respect to the control (about 22% and 9% for APD and p-NAD respectively). 相似文献