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51.
Mahnaz Parvaneh Nejad Shirazi Mohammad Bahrami Hassan Amiri Bakhtiar Omid Bamdad 《Historical Biology》2013,25(4):493-501
The Jahrum Formation act as reservoir rocks in the Zagros Mountains west of Iran. For the study of this formation, a stratigraphic section of Lapoee which is situated north of Shiraz has been examined. Petrographic and stratigraphic results along with field observations show that the Jahrum Formation consists of cream-grey thin-to-medium-bedded limestone so that at the top of the formation, they are locally changed to dolomite. The Jahrum Formation overlies the Sachun Formation. We also found Nubecularids as paleoecology indicators in middle parts of the Jahrum Formation. The presence of Nubecularids in the Lapoee stratigraphic section (i.e. the Jahrum Formation) indicates a lagoon depositional environment. 相似文献
52.
Hadian K Griesbach RA Dornauer S Wanger TM Nagel D Metlitzky M Beisker W Schmidt-Supprian M Krappmann D 《The Journal of biological chemistry》2011,286(29):26107-26117
The IκB kinase (IKK) complex acts as a gatekeeper of canonical NF-κB signaling in response to upstream stimulation. IKK activation requires sensing of ubiquitin chains by the essential IKK regulatory subunit IKKγ/NEMO. However, it has remained enigmatic whether NEMO binding to Lys-63-linked or linear ubiquitin chains is critical for triggering IKK activation. We show here that the NEMO C terminus, comprising the ubiquitin binding region and a zinc finger, has a high preference for binding to linear ubiquitin chains. However, immobilization of NEMO, which may be reminiscent of cellular oligomerization, facilitates the interaction with Lys-63 ubiquitin chains. Moreover, selective mutations in NEMO that abolish association with linear ubiquitin but do not affect binding to Lys-63 ubiquitin are only partially compromising NF-κB signaling in response to TNFα stimulation in fibroblasts and T cells. In line with this, TNFα-triggered expression of NF-κB target genes and induction of apoptosis was partially compromised by NEMO mutations that selectively impair the binding to linear ubiquitin chains. Thus, in vivo NEMO interaction with linear and Lys-63 ubiquitin chains is required for optimal IKK activation, suggesting that both type of chains are cooperating in triggering canonical NF-κB signaling. 相似文献
53.
Elisa Rasouli Wan Jeffrey Basirun Mohd Rafie Johan Majid Rezayi Majid Darroudi Kamyar Shameli Zohreh Shanavaz Omid Akbarzadeh Zahra Izadiyan 《Journal of cellular biochemistry》2019,120(4):6624-6631
In the present research, we report a greener, faster, and low-cost synthesis of gold-coated iron oxide nanoparticles (Fe3O4/Au-NPs) by different ratios (1:1, 2:1, and 3:1 molar ratio) of iron oxide and gold with natural honey (0.5% w/v) under hydrothermal conditions for 20 minutes. Honey was used as the reducing and stabilizing agent, respectively. The nanoparticles were characterized by X-ray diffraction (XRD), UV-visible spectroscopy, field emission scanning electron microscope (FESEM), energy-dispersive X-ray spectroscopy (EDXS), transmission electron microscopy (TEM), selected area electron diffraction (SAED), vibrating sample magnetometer (VSM), and fourier transformed infrared spectroscopy (FT-IR). The XRD analysis indicated the presence of Fe3O4/Au-NPs, while the TEM images showed the formation of Fe3O4/Au-NPs with diameter range between 3.49 nm and 4.11 nm. The VSM study demonstrated that the magnetic properties were decreased in the Fe3O4/Au-NPs compared with the Fe3O4-NPs. The cytotoxicity threshold of Fe3O4/Au-NPs in the WEHI164 cells was determined by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. It was demonstrated no significant toxicity in higher concentration up to 140.0 ppm which can become the main candidates for biological and biomedical applications, such as drug delivery. 相似文献
54.
Hossein Ghanaatian Jobzari Parvaneh Iranmanesh Mohammad Sabet Samira Saeednia 《Luminescence》2019,34(7):689-698
In this experimental study, ZnS nanostructures were synthesized using two hydrothermal and co‐precipitation methods with different precursors. Different reagents and precursors were changed to obtain the best product size and morphology. The structure and crystal phase of the products were studied using X‐ray diffraction (XRD) patterns. Some structural parameters were calculated using the XRD results and a product composition was obtained by energy dispersive X‐ray (EDX) analysis and Fourier transform infrared (FT‐IR) spectra to study the chemical composition. The size and morphology of ZnS nanostructures were obtained by scanning electron microscopy (SEM). The optical properties of the synthesized ZnS nanostructures were examined using ultraviolet–visible (UV–Vis) spectra to estimate the optical band gap. Band gap energies were higher than those in the ZnS bulk sample, mainly due to quantum size effects. The photoluminescence (PL) properties of the products were investigated using PL spectra. The results showed the effect of two factors, namely synthesis method and chemical reagents, on the structure parameters, crystallite size, product size and morphology, and optical and PL properties. 相似文献
55.
There are significant challenges to restoring binaural hearing to children who have been deaf from an early age. The uncoordinated and poor temporal information available from cochlear implants distorts perception of interaural timing differences normally important for sound localization and listening in noise. Moreover, binaural development can be compromised by bilateral and unilateral auditory deprivation. Here, we studied perception of both interaural level and timing differences in 79 children/adolescents using bilateral cochlear implants and 16 peers with normal hearing. They were asked on which side of their head they heard unilaterally or bilaterally presented click- or electrical pulse- trains. Interaural level cues were identified by most participants including adolescents with long periods of unilateral cochlear implant use and little bilateral implant experience. Interaural timing cues were not detected by new bilateral adolescent users, consistent with previous evidence. Evidence of binaural timing detection was, for the first time, found in children who had much longer implant experience but it was marked by poorer than normal sensitivity and abnormally strong dependence on current level differences between implants. In addition, children with prior unilateral implant use showed a higher proportion of responses to their first implanted sides than children implanted simultaneously. These data indicate that there are functional repercussions of developing binaural hearing through bilateral cochlear implants, particularly when provided sequentially; nonetheless, children have an opportunity to use these devices to hear better in noise and gain spatial hearing. 相似文献
56.
57.
Isatin-3-isonicotinylhydrazone was synthesized and characterized. The interaction of native calf thymus DNA with isatin-3-isonicotinylhydrazone
(IINH) in 10 mM Tris–HCl aqueous solutions at neutral pH 7.4 has been investigated by spectrophotometric, circular dichroism
(CD), melting temperature (T
m
), spectrofluorimetric, and viscometric techniques. It is found that IINH molecules could intercalate between base pairs of
DNA as are evidenced by: hypochromism in UV absorption band of IINH, induced CD spectral changes, sharp increase in specific
viscosity of DNA, and increase in the fluorescence of methylene blue (MB)-DNA solutions in the presence of increasing amounts
of IINH, which indicates that it is able to release the intercalated MB completely. The binding constants of IINH–DNA complex
at four different temperatures (277, 288, 298, and 310 K) were calculated to be 4.7 × 104, 2.2 × 104, 1.75 × 104 and 1.1 × 104 M−1, respectively. Furthermore, the enthalpy and entropy of the reaction between IINH and CT-DNA showed that the reaction is
enthalpy-favored and entropy- disfavored (∆H = −30.187 kJ mol−1; ∆S = −20.46 J mol−1K−1) which are other evidences to indicate the IINH is able to be intercalated in the DNA base pairs. 相似文献
58.
Fatemeh Vahid Dastjerdi Bahman Zeynali Azita Parvaneh Tafreshi Anahita Shahraz Mahin Sadat Chavoshi Irandokht Khaki Najafabadi Marzieh Mowlavi Vardanjani Amir Atashi Masoud Soleimani 《Cell biology international》2012,36(11):967-972
GSK‐3β is a key molecule in several signalling pathways, including the Wnt/β‐catenin signalling pathway. There is increasing evidence suggesting Wnt/β‐catenin signalling is involved in the neural differentiation of embryonic, somatic and neural stem cells. However, a large body of evidence indicates that this pathway maintains stem cells in a proliferative state. To address this controversy, we have investigated whether the Wnt/β‐catenin pathway is present and involved in the neural differentiation of newly introduced USSCs (unrestricted somatic stem cells). Our results indicate that the components of Wnt/β‐catenin signalling are present in undifferentiated USSCs. We also show that the treatment of neurally induced USSCs with BIO (6‐bromoindirubin‐3′‐oxime), a specific GSK‐3β inhibitor and Wnt activator, for 5 and 10 days results in increased expression of a general neuronal marker (β‐tubulin III). Moreover, the expression of pGSK‐3β and stabilized β‐catenin increased by BIO in neurally induced USSCs, indicates that the Wnt pathway is activated and functional in these cells. Thus, inhibition of GSK‐3β in USSCs enhances their neural differentiation, which suggests a positive role of the Wnt/β‐catenin signalling pathway towards neural fate. 相似文献
59.
60.
Trinkaus E Biglari F Mashkour M Monchot H Reyss JL Rougier H Heydari S Abdi K 《American journal of physical anthropology》2008,135(4):371-378
Paleontological analysis of remains from Wezmeh Cave in western Iran have yielded a Holocene Chalcolithic archeological assemblage, a rich Late Pleistocene carnivore faunal assemblage, and an isolated unerupted human maxillary premolar (P(3) or possibly P(4)). Species representation and U-series dating of faunal teeth place the carnivore assemblage during oxygen isotope stages (OIS) 3 and 2, and noninvasive gamma spectrometry dating of the human premolar places it at least as old as early OIS 2. The human premolar crown morphology is not diagnostic of late archaic versus early modern human affinities, but its buccolingual diameter places it at the upper limits of Late Pleistocene human P(3) and P(4) dimensions and separate from a terminal Pleistocene regional sample. Wezmeh Cave therefore provides additional Paleolithic human remains from the Zagros Mountains and further documents Late Pleistocene human association with otherwise carnivore-dominated cave assemblages. 相似文献