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51.
1. Activities of glucose 6-phosphate dehydrogenase (EC 1.1.1.49), 6-phosphogluconate dehydrogenase (EC 1.1.1.44), isocitrate dehydrogenase (EC 1.1.1.42), malate dehydrogenase (EC 1.1.1.37), malate dehydrogenase (decarboxylating) (EC 1.1.1.40), and pyruvate carboxylase (EC 6.4.1.1) were determined in subcellular fractions of mammary gland from rabbits during pregnancy, at different stages of lactation and during weaning. The results were compared with those obtained in similar experiments with rat mammary gland. 2. Three bases of expression of the activity of enzymes in the particle-free supernatant fraction of mammary gland were compared. During lactation, activity expressed per mg. of particle-free supernatant protein (uncorrected for milk protein) correlated well with that expressed per mug. of DNA phosphorus. The disadvantages of expressing activities per g. wet wt. are discussed. 3. The major differences between the two tissues were: (a) neither malate dehydrogenase (decarboxylating) nor a soluble form of pyruvate carboxylase could be detected in rabbit mammary gland at any stage of the lactation cycle; (b) isocitrate dehydrogenase increased in activity during lactation in rabbit mammary gland, but not in that of the rat. 4. Pyruvate carboxylase in the mitochondrial fraction of rabbit mammary gland, and in both the mitochondrial and the soluble fractions of rat mammary gland, did not change in activity during lactation. 5. For each tissue, the NADP-dependent dehydrogenases studied had a high activity at all stages of the lactation cycle compared with the rate of fatty acid synthesis at mid-lactation. The significance of these results is discussed with respect to the supply of NADPH via NADH. 相似文献
52.
Haloarchaeal diversity in the crystallizers of Adriatic Secovlje salterns was investigated using gene fragments encoding 16S rRNA and bacteriorhodopsin as molecular markers. Screening of 180 clones from five gene libraries constructed for each gene targeted revealed 15 different 16S rRNA and 10 different bacteriorhodopsin phylotypes, indicating higher haloarchaeal diversity than previously reported in such hypersaline environments. Furthermore, results of rarefaction analysis indicated that analysis of an increasing number of clones would have revealed additional diversity. Finally, most sequences from the crystallizers grouped within the Halorubrum branch, whereas square-shaped 'Haloquadratum' relatives, repeatedly reported to dominate crystallizer communities, were rare. Presence of such special and diverse haloarchaeal community could be attributed to the Secovlje salterns rare continuous short-cycling salt production mechanism. 相似文献
53.
Eda Dagsuyu Pınar Koroglu Ilknur B. Gul Omur K. Bulan Refiye Yanardag 《Journal of biochemical and molecular toxicology》2023,37(10):e23440
The body can host the spread of prostate cancer cells. Metastases from prostate cancer are more frequently seen in the brain, liver, lungs, and lymph nodes. A well-known antidiabetic drug, metformin, is also known to have antitumor effects. Our study focuses on the evaluation of potential metformin protective effects on brain and cerebellum damage in streptozotocin (STZ)-induced diabetic and Dunning prostate cancer models. In this investigation, six groups of male Copenhagen rats were created: control, diabetic (D), cancer (C), diabetic + cancer (DC), cancer + metformin, and diabetic + cancer + metformin. The brain and cerebellum tissues of the rats were taken after sacrifice. Oxidative stress markers including reduced glutathione level, lipid peroxidation, glutathione reductase, glutathione peroxidase, glutathione-S-transferase, catalase, superoxide dismutase activities, reactive oxygen species, total oxidant and total antioxidant status, lactate dehydrogenase, xanthine oxidase, acetylcholinesterase activities, protein carbonyl contents, nitric oxide and OH-proline levels, sodium potassium ATPase, carbonic anhydrase, and glucose-6-phosphate dehydrogenase activities; glycoprotein levels including hexose, hexosamine, fucose, and sialic acid levels; and histone deacetylase activity as a cancer marker were determined. Oxidative stress markers were impaired and glycoprotein levels and histone deacetylase activity were increased in the D, C, and DC groups. Metformin therapy reversed these effects. Metformin was found to protect the brain and cerebellum of STZ-induced diabetic rats with Dunning prostate cancer from harm caused by MAT-Lylu metastatic cells. 相似文献
54.
The covalent immobilization of bovine liver catalase (CAT) on to florisil via glutaraldehyde was investigated. Optimum immobilization pH and temperature were determined as pH 6.0, 10 degrees C respectively, while the amount of initial CAT per g of carrier and immobilization time was determined as 5 mg g(-1) and 120 min, respectively. The Vmax values for free and immobilized CAT were found to be 1.7 x 10(5) and 2.0 x 10(4) micromol H2O2 min(-1) mg protein(-1), respectively, whereas KM values were 33.3 mM and 1722.0 mM respectively. Operational stability was determined by using a stirred batch-type column reactor. Immobilized CAT retained about 40% of its initial activity after 50 uses. It showed higher storage stability than free CAT at 4 degrees C and 25 degrees C. Its storage stability increased with increasing relative humidity (RH) from 0 to 20% of the medium. The highest storage stability was obtained in 20% RH, however, further increase in RH from 40 to 100% significantly decreased the storage stability. 相似文献
55.
Faheem Shah Tasneem Gul Kazi Hassan Imran Afridi Naveed Kazi Jameel Ahmed Baig Abdul Qadir Shah Sumaira Khan Nida Fatima Kolachi Sham Kumar Wadhwa 《Biological trace element research》2011,141(1-3):131-149
Anemia affects a substantial portion of the world’s population, provoking severe health problems as well as important economic losses to the region in which this condition is found. This study was designed to compare the levels of essential trace and toxic elements in scalp hair, blood, and urine samples of anemic children (n = 132) with age range 1–5 and 6–10 years of both genders. For a comparative study, 134 non-anemic age- and sex-matched children as control subjects, residing in the same city, were selected. The metals in the biological samples were measured by flame atomic absorption spectrophotometry/electrothermal atomic absorption spectrometry prior to microwave-assisted acid digestion. The proposed method was validated using certified reference samples of hair, blood, and urine. The results indicated significantly lower levels of iron, copper, and zinc in the biological samples as compared to the control children of both genders (p = 0.01–0.008). The mean values of lead and cadmium were significantly high in all three biological samples of anemic children as compared to non-anemic children of both age groups (p = 0.005–0.001). The ratios of essential metal to toxic metals in the biological samples of anemic children of both age groups were significantly lower than that of controls. Deficiency of essential trace metals and high level of toxic metals may play a role in the development of anemia in the subjects under study. 相似文献
56.
Hassan Imran Afridi Tasneem Gul Kazi Naveed Kazi Ghulam Abbas Kandhro Abdul Qadir Shah Jameel Ahmed Baig Sham Kumar Wadhwa Sumaira Khan Nida Fatima Kolachi Faheem Shah Mohammad Khan Jamali Mohammad Balal Arain 《Biological trace element research》2011,143(1):103-115
This study was designed to compare the levels of chromium (Cr) and manganese (Mn) in scalp hair, blood, and urine of night blindness in children age ranged (3–7) and (8–12) years of both genders, comparing them to sex- and age-matched controls. A microwave-assisted wet acid digestion procedure, was developed as a sample pretreatment, for the determination of Cr and Mn in biological samples of night blindness children. The proposed method was validated by using conventional wet digestion and certified reference samples of hair, blood and urine. The digests of all biological samples were analyzed for Cr and Mn by electrothermal atomic absorption spectrometry. The results indicated significantly higher levels of Cr, whilst low level of Mn in the biological samples (blood and scalp hair) of male and female night blindness children, compared with control subjects of both genders. These data present guidance to clinicians and other professional investigating deficiency of Mn and excessive level of Cr in biological samples (scalp hair and blood) of night blindness children. 相似文献
57.
Bahriye Karakas Yeliz Ozmay Huveyda Basaga Ozgur Gul Ozgur Kutuk 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2018,1865(8):1073-1087
Despite the development of novel targeted therapies, de novo or acquired chemoresistance remains a significant factor for treatment failure in breast cancer therapeutics. Neratinib and dacomitinib are irreversible panHER inhibitors, which block their autophosphorylation and downstream signaling. Moreover, neratinib and dacomitinib have been shown to activate cell death in HER2-overexpressing cell lines. Here we showed that increased MCL1 and decreased BIM and PUMA mediated resistance to neratinib in ZR-75-30 and SKBR3 cells while increased BCL-XL and BCL-2 and decreased BIM and PUMA promoted neratinib resistance in BT474 cells. Cells were also cross-resistant to dacomitinib. BH3 profiles of HER2+ breast cancer cells efficiently predicted antiapoptotic protein dependence and development of resistance to panHER inhibitors. Reactivation of ERK1/2 was primarily responsible for acquired resistance in SKBR3 and ZR-75-30 cells. Adding specific ERK1/2 inhibitor SCH772984 to neratinib or dacomitinib led to increased apoptotic response in neratinib-resistant SKBR3 and ZR-75-30 cells, but we did not detect a similar response in neratinib-resistant BT474 cells. Accordingly, suppression of BCL-2/BCL-XL by ABT-737 was required in addition to ERK1/2 inhibition for neratinib- or dacomitinib-induced apoptosis in neratinib-resistant BT474 cells. Our results showed that different mitochondrial apoptotic blocks mediated acquired panHER inhibitor resistance in HER2+ breast cancer cell lines as well as highlighted the potential of BH3 profiling assay in prediction of panHER inhibitor resistance in breast cancer cells. 相似文献
58.
Frequent genes in rare diseases: panel‐based next generation sequencing to disclose causal mutations in hereditary neuropathies 下载免费PDF全文
Maike F. Dohrn Nicola Glöckle Lejla Mulahasanovic Corina Heller Julia Mohr Christine Bauer Erik Riesch Andrea Becker Florian Battke Konstanze Hörtnagel Thorsten Hornemann Saranya Suriyanarayanan Markus Blankenburg Jörg B. Schulz Kristl G. Claeys Burkhard Gess Istvan Katona Andreas Ferbert Debora Vittore Alexander Grimm Stefan Wolking Ludger Schöls Holger Lerche G. Christoph Korenke Dirk Fischer Bertold Schrank Urania Kotzaeridou Gerhard Kurlemann Bianca Dräger Anja Schirmacher Peter Young Beate Schlotter‐Weigel Saskia Biskup 《Journal of neurochemistry》2017,143(5):507-522
59.
Eisinger-Mathason TS Andrade J Groehler AL Clark DE Muratore-Schroeder TL Pasic L Smith JA Shabanowitz J Hunt DF Macara IG Lannigan DA 《Molecular cell》2008,31(5):722-736
Stress granules aid cell survival in response to environmental stressors by acting as sites of translational repression. We report an unanticipated link between stress granules and the serine/threonine kinase RSK2. In stressed breast cells, endogenous RSK2 colocalizes in granules with TIA-1 and poly(A)-binding protein 1, and the sequestration of RSK2 and TIA-1 exhibits codependency. The RSK2 N-terminal kinase domain controls the direct interaction with the prion-related domain of TIA-1. Silencing RSK2 decreases cell survival in response to stress. Mitogen releases RSK2 from the stress granules and permits its nuclear import via a nucleocytoplasmic shuttling sequence in the C-terminal domain. Nuclear accumulation is dependent on TIA-1. Surprisingly, nuclear localization of RSK2 is sufficient to enhance proliferation through induction of cyclin D1, in the absence of other active signaling pathways. Hence, RSK2 is a pivotal factor linking the stress response to survival and proliferation. 相似文献
60.
Preformulation studies were performed on a hemiglutarate ester prodrug of Δ9-tetrahydrocannabinol (THC-HG), to facilitate the development of stable formulations by hot-melt methods. The various studies
performed included solid-state thermal characterization, pKa, logP, aqueous and pH dependent solubility, pH stability and
effect of moisture, temperature and oxygen on solid-state stability. A hot-melt method was utilized to fabricate THC-HG incorporated
poly (ethylene oxide) (PEO) matrices and the bioadhesive properties, release profiles and post-processing stability of these
matrices were assessed as a function of the polymer molecular weight. The prodrug exhibited a T
g close to 0°C, indicating its amorphous nature. Thermogravimetric analysis revealed a rapid weight loss after 170°C. The prodrug
exhibited a seven-fold higher aqueous solubility as compared to the parent drug (THC). Also, the solubility of the compound
increased with increasing pH, being maximum at pH 8. The prodrug exhibited a v-shaped pH-rate profile, with the degradation
rate minimum between pH 3 and 4. The moisture uptake and drug degradation increased with an increase in relative humidity.
Solid-state stability indicated that the prodrug was stable at −18°C but demonstrated higher degradation at 4°C, 25°C and
40°C (51.6%, 74.5% and 90.1%, respectively) at the end of 3-months. THC-HG was found to be sensitive to the presence of oxygen.
The release of the active from the polymeric matrices decreased, while bioadhesion increased, with an increase in molecular
weight of PEO. 相似文献