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41.
Acute and sub-acute toxic effects of a novel phosphorothionate coded as RPR-II on testis of albino rats were studied. In acute study rats received a single dose of 12.3 mg/kg of RPR-II and sacrificed after 24 hr. For sub-acute study 0.58 mg/kg/day was administered orally to rats for 10 and 21 days. Acute exposure of rats to RPR-II brought no change either in the gonadosomatic index (GSI) or in the structure of testis or in the serum levels of testosterone. Testis glutathione (GSH) level and glutathione S-transferase (GST) activity was significantly decreased whereas, acid phosphatase (AcP) levels increased significantly at 24 hr post-treatment. On 7th day (withdrawal period) after the cessation of the treatment the GSH, GST, AcP, and AkP levels reached to near control. The sub-acute study revealed a significant decrease in GSI on 10th and 21st day of the treatment. In contrast, a time-dependent and significant increased in GSH level and GST activity was observed on 100th and 21st day of post-treatment, except GSH level on 10th day, which was declined. Due to RPR-II treatment the testis AcP and alkaline phosphatase (AkP) levels were significant at both 10th and 21st day of medication but AcP levels were increased whereas AkP levels decreased. The histopathological studies on day 10th showed considerable loss of spermatozoids in testis and at 21st day complete derangement of cellular organization was observed. Testosterone levels decreased significantly on 10th day and remained significantly low at 21st day. However, withdrawal studies showed a recovery in testis of rat treated with RPR-II. GST, GSH, GSI, AcP and AkP values recovered, testosterone levels were also well recovered but recovery in testis structure remained at a low profile. The present study suggests that RPR-II may cause testicular toxicity in rats affecting the normal functioning of testis and it also gave some new information in withdrawal studies.  相似文献   
42.
43.
This study focuses on karyological investigation of four taxa of Dianthus (Caryophyllaceae) including D. crossopetalus, D. orientalis subsp. stenocalyx, D. orientalis subsp. gorganicus, and Dianthus sp. distributed in Northeast of Iran. The karyotype asymmetry/symmetry was evaluated using two methods: 1) CVCL (coefficient of variation of chromosome length) and CVCI (heterogeneity of the centromeric index); and 2) MCA (mean centromeric asymmetry). The karyotype asymmetry was also used to investigate the relationships among the taxa. Results obtained from the current study revealed that there are two different ploidy levels (2n = 2x = 30 and 2n = 4x = 60) among the investigated taxa. The indices CVCL and MCA described karyotype asymmetry correctly based on variation in chromosome length. Diagram of CVCL vs. MCA seems to be appropriate for karyological delimitation and taxonomic relationships among the Dianthus taxa under study. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
44.

Introduction

Mitragynine is a major bioactive compound of Kratom, which is derived from the leave extracts of Mitragyna speciosa Korth or Mitragyna speciosa (M. speciosa), a medicinal plant from South East Asia used legally in many countries as stimulant with opioid-like effects for the treatment of chronic pain and opioid-withdrawal symptoms. Fatal incidents with Mitragynine have been associated with cardiac arrest. In this study, we determined the cardiotoxicity of Mitragynine and other chemical constituents isolated using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs).

Methods and Results

The rapid delayed rectifier potassium current (I Kr), L-type Ca2+ current (I Ca,L) and action potential duration (APD) were measured by whole cell patch-clamp. The expression of KCNH2 and cytotoxicity was determined by real-time PCR and Caspase activity measurements. After significant I Kr suppression by Mitragynine (10 µM) was confirmed in hERG-HEK cells, we systematically examined the effects of Mitragynine and other chemical constituents in hiPSC-CMs. Mitragynine, Paynantheine, Speciogynine and Speciociliatine, dosage-dependently (0.1∼100 µM) suppressed I Kr in hiPSC-CMs by 67% ∼84% with IC50 ranged from 0.91 to 2.47 µM. Moreover, Mitragynine (10 µM) significantly prolonged APD at 50 and 90% repolarization (APD50 and APD90) (439.0±11.6 vs. 585.2±45.5 ms and 536.0±22.6 vs. 705.9±46.1 ms, respectively) and induced arrhythmia, without altering the L-type Ca2+ current. Neither the expression,and intracellular distribution of KCNH2/Kv11.1, nor the Caspase 3 activity were significantly affected by Mitragynine.

Conclusions

Our study indicates that Mitragynine and its analogues may potentiate Torsade de Pointes through inhibition of I Kr in human cardiomyocytes.  相似文献   
45.
In this paper we describe a fast and mild method based on the use of a unique cation exchanger and buffers containing ethylene glycol and salt for the purification of the myelin basic protein (MBP; MW 18.5 kDa). MBP thus purified hydrolyses catalytically p-nitrophenyl acetate. This esterase activity facilitates not only the purification of MBP but also indicates that probably it is in its native state, i.e. there is a good chance that the purified molecules are structurally and chemically identical. This is a prerequisite to obtain crystals appropriate for x-ray diffraction and other studies.Abbreviations used MBP myelin basic protein - MW molecular weight - kDa kilo Dalton - octyl-POE n-octylpolydisperse oligooxyethylene - CHAPS 3-3-cholamidopropyl dimethylammonio-1-propane-sulfonate - CTAB cetyltrimethylammonium bromide - SDS sodium dodecyl sulfate - SDS-PAGE polyacrylamide gel electrophoresis in the presence of SDS - G 3707 heptaoxyethylene lauryl ether - TWEEN-20 polyoxyethylenesorbitan-monolaurat - EDTA ethylenediaminetetraacetic acid - HEPES N-(2-hydroxyethyl)-piperazine-N-(2-ethanesulfonic acid)  相似文献   
46.
Striga hermonthica (Striga) is an obligate hemiparasitic weed, causing severe yield losses in cereals, including rice, throughout sub-Saharan Africa. Striga germination depends on strigolactones (germination stimulants) exuded by the host roots. The interspecific New Rice for Africa (NERICA) cultivars offer a potentially interesting gene pool for a screen for low germination-inducing rice cultivars. Exudates were collected from all NERICA cultivars and their parents (Oryza sativa and Oryza glaberrima) for the analysis of strigolactones. In vitro and in situ Striga germination, attachment and emergence rates were recorded for each cultivar. NERICA 1 and CG14 produced significantly less strigolactones and showed less Striga infection than the other cultivars. NERICAs 7, 8, 11 and 14 produced the largest amounts of strigolactones and showed the most severe Striga infection. Across all the cultivars and parents, there was a positive relationship between the amount of strigolactones in the exudate and Striga germination, attachment and emergence rates. This study shows that there is genetic variation in Striga pre-attachment resistance in NERICA rice. Cultivars combining this pre-attachment resistance with post-attachment resistance (already identified) can provide a key component for durable integrated management of this noxious weed in cereal production systems in sub-Saharan Africa.  相似文献   
47.

Background

There are several reports on anatomical differences of the meniscus. However, there are only a few reports on abnormalities in both menisci and anatomical differences in anterior cruciate ligament insertions.

Case presentation

This is a case report of a 36-year-old Hispanic man presenting symptoms, including knee pain, locking, and effusion, with an anatomical abnormality of the menisci corresponding to the fusion of the posterior horns of the menisci in tandem with the insertion of the posterior meniscus fibers in the anterior cruciate ligament.

Conclusions

This is the first study describing a meniscus anatomical variant with isolated posterior junction of the posterior horn with an anomalous insertion to the anterior cruciate ligament. The recognition of meniscus variants is important as they can be misinterpreted for more significant pathology on magnetic resonance images.
  相似文献   
48.
Probiotics and Antimicrobial Proteins - Longevity of probiotic is the main concern for getting maximum benefits when added in food product. Bifidobacterium, a probiotic, tends to lose its viability...  相似文献   
49.
The putative capsule O-acetyltransferase gene wcjE is highly conserved across various Streptococcus pneumoniae serotypes, but the role of the gene in capsule biosynthesis and bacterial fitness remains largely unclear. Isolates expressing pneumococcal serotype 9A arise from precursors expressing wcjE-associated serotype 9V through loss-of-function mutation to wcjE. To define the biosynthetic role of 9V wcjE, we characterized the structure and serological properties of serotype 9V and 9A capsule polysaccharide (PS). NMR data revealed that both 9V and 9A PS are composed of an identical pentasaccharide repeat unit, as reported previously. However, in sharp contrast to previous studies on 9A PS being devoid of any O-acetylation, we identified O-acetylation of α-glucuronic acid and α-glucose in 9A PS. In addition, 9V PS also contained -CH(2) O-acetylation of β-N-acetylmannosamine, a modification that disappeared following in vitro recombinatorial deletion of wcjE. We also show that serotyping sera and monoclonal antibodies specific for 9V and 9A bound capsule PS in an O-acetate-dependent manner. Furthermore, IgG and to a lesser extent IgM from human donors immunized with serotype 9V PS displayed stronger binding to 9V compared with 9A PS. We conclude that serotype 9V wcjE mediates 6-O-acetylation of β-N-acetylmannosamine. This PS modification can be selectively targeted by antibodies in immunized individuals, identifying a potential selective advantage for wcjE inactivation and serotype 9A emergence.  相似文献   
50.
Although glyphosate-resistant (GR) technology is used in most countries producing soybeans (Glycine max L.), there are no particular fertilize recommendations for use of this technology, and not much has been reported on the influence of glyphosate on GR soybean nutrient status. An evaluation of different cultivar maturity groups on different soil types, revealed a significant decrease in macro and micronutrients in leaf tissues, and in photosynthetic parameters (chlorophyll, photosynthetic rate, transpiration and stomatal conductance) with glyphosate use (single or sequential application). Irrespective of glyphosate applications, concentrations of shoot macro- and micronutrients were found lower in the near-isogenic GR-cultivars compared to their respective non-GR parental lines Shoot and root dry biomass were reduced by glyphosate with all GR cultivars evaluated in both soils. The lower biomass in GR soybeans compared to their isogenic normal lines probably represents additive effects from the decreased photosynthetic parameters as well as lower availability of nutrients in tissues of the glyphosate treated plants.  相似文献   
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