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1.
Chronic pressure overload leads to an increase in the size, i.e. hypertrophy, of cardiomyocytes in the heart. However, the molecular mechanisms underlying this hypertrophy are not understood. Insulin-like growth factor-I (IGF-I) synthesized locally in the heart is known to be associated with the hypertrophic process. So far, however, cardiac IGF-I gene expression in the widely used rat model system has only been shown to be increased when the hypertrophy induced by pressure-overload was already established. Therefore, the question of whether IGF-I serves as an initiating or early-enhancing factor for the cardiac hypertrophy remains unanswered. Here, cardiac hypertension and hypertrophy were rapidly induced in the rat by complete constriction of the abdominal aorta between the origins of the renal arteries. Carotid arterial systolic blood pressure remained unchanged in sham rats but increased rapidly in the pressure-overloaded constricted rats with a sustained hypertension established by 3 days. Hypertrophy of left ventricular (LV) cardiomyocytes in constricted rats also occurred by 3 days. However, this hypertrophy was preceded by increases in LV IGF-I mRNA and protein which occurred within 1 day. These results support the hypothesis that cardiac-synthesized IGF-I is an initiating or early-enhancing factor for hypertrophy of LV cardiomyocytes.  相似文献   
2.
Razzaq A  Su Y  Mehren JE  Mizuguchi K  Jackson AP  Gay NJ  O'Kane CJ 《Gene》2000,241(1):167-174
A sequence similarity search of the Drosophila nucleotide database using vertebrate amphiphysin as a query identified a cDNA that encodes a Drosophila amphiphysin. The predicted protein has conserved sequence domains that should enable it to dimerise and bind to dynamin. Structural modelling suggests that the Src-homology-3 (SH3) domains of vertebrate and Drosophila amphiphysins are highly similar, supporting the putative ability of the latter to bind dynamin. However, the fly amphiphysin shows less conservation to sequences in the vertebrate amphiphysins that bind other endocytic components such as clathrin, AP-2 and endophilin. Amphiphysin is a single-copy gene that maps to position 49B on polytene chromosomes. Messenger RNA of this amphiphysin is expressed widely during embryogenesis and has elevated expression in a number of sites including the foregut, hindgut and epidermis, but not in the central nervous system. Taken together, these data are consistent with a role for Drosophila amphiphysin in endocytosis, but the details of this role may differ from that of vertebrate amphiphysins.  相似文献   
3.

Background

Increasing evidence associates excess refined sugar intakes with obesity, Type 2 diabetes and heart disease. Worryingly, the estimated volume of sugary drinks purchased in the UK has more than doubled between 1975 and 2007, from 510ml to 1140ml per person per week. We aimed to estimate the potential impact of a duty on sugar sweetened beverages (SSBs) at a local level in England, hypothesising that a duty could reduce obesity and related diseases.

Methods and Findings

We modelled the potential impact of a 20% sugary drinks duty on local authorities in England between 2010 and 2030. We synthesised data obtained from the British National Diet and Nutrition Survey (NDNS), drinks manufacturers, Office for National Statistics, and from previous studies. This produced a modelled population of 41 million adults in 326 lower tier local authorities in England. This analysis suggests that a 20% SSB duty could result in approximately 2,400 fewer diabetes cases, 1,700 fewer stroke and coronary heart disease cases, 400 fewer cancer cases, and gain some 41,000 Quality Adjusted Life Years (QALYs) per year across England. The duty might have the biggest impact in urban areas with young populations.

Conclusions

This study adds to the growing body of evidence suggesting health benefits for a duty on sugary drinks. It might also usefully provide results at an area level to inform local price interventions in England.  相似文献   
4.

Background

Low concentrations of nitric oxide (NO) are necessary for the biology and physiology of spermatozoa, but high levels of NO are toxic and have negative effects on sperm functions. Although several studies have considered the relationship between infertility and semen NO concentrations, no study on the effects of asthenospermia treatments such as oral zinc supplementation on concentrations of NO, which are important in fertility, has been reported. Studies have shown that oral zinc supplementation develops sperm count, motility and the physical characteristics of sperm in animals and in some groups of infertile men. The present study was conducted to study the effect of zinc supplementation on the quantitative and qualitative characteristics of semen, along with enzymes of the NO pathway in the seminal plasma of asthenospermic patients.

Methods

Semen samples were obtained from 60 fertile and 60 asthenozoospermic infertile men of matched age. The subfertile group was treated with zinc sulfate; each participant took two capsules (220 mg per capsule) per day for 3 months. Semen samples were obtained (before and after zinc sulfate supplementation). After liquefaction of the seminal fluid at room temperature, routine semen analyses were performed. The stable metabolites of NO (nitrite) in seminal plasma were measured by nitrophenol assay. Arginase activity and NO synthase activity were measured spectrophotometrically.

Results

Peroxynitrite levels, arginase activity, NO synthase activity and various sperm parameters were compared among fertile controls and infertile patients (before and after treatment with zinc sulfate). Peroxynitrite levels and NO synthase activity were significantly higher in the infertile patients compared to the fertile group. Conversely, arginase activity was significantly higher in the fertile group than the infertile patients. Peroxynitrite levels, arginase activity and NO synthase activity of the infertile patient were restored to normal values after treatment with zinc sulfate. Volume of semen, progressive sperm motility percentage and total normal sperm count were increased after zinc supplementation.

Conclusions

Treatment of asthenospermic patients with zinc supplementation leads to restored peroxynitrite levels, arginase activity and NO synthase activity to normal values and gives a statistically significant improvement of semen parameters compared with controls.

Trial registration

ClinicalTrials.gov identifier: NCT01684059  相似文献   
5.
Internet worms are analogous to biological viruses since they can infect a host and have the ability to propagate through a chosen medium. To prevent the spread of a worm or to grasp how to regulate a prevailing worm, compartmental models are commonly used as a means to examine and understand the patterns and mechanisms of a worm spread. However, one of the greatest challenge is to produce methods to verify and validate the behavioural properties of a compartmental model. This is why in this study we suggest a framework based on Petri Nets and Model Checking through which we can meticulously examine and validate these models. We investigate Susceptible-Exposed-Infectious-Recovered (SEIR) model and propose a new model Susceptible-Exposed-Infectious-Recovered-Delayed-Quarantined (Susceptible/Recovered) (SEIDQR(S/I)) along with hybrid quarantine strategy, which is then constructed and analysed using Stochastic Petri Nets and Continuous Time Markov Chain. The analysis shows that the hybrid quarantine strategy is extremely effective in reducing the risk of propagating the worm. Through Model Checking, we gained insight into the functionality of compartmental models. Model Checking results validate simulation ones well, which fully support the proposed framework.  相似文献   
6.
Despite increasing evidence indicating the essential involvement of selenium (Se) on growth performance, antioxidant capacity, and meat quality of commercial broilers, the effects of different Se sources on local Chinese Subei chickens is unclear. A total of 360 50-day-old male chickens were individually weighed and randomly allocated to four treatment groups. Chickens in each of the four groups were fed diets supplemented with 0.3 mg Se/kg as sodium Se (SS), Se-enriched yeast (SY), selenomethionine (Met-Se), or nano red element Se (Nano-Se) for 40 days. At the end of the experiment, one bird of approximately average weight from each cage was selected and slaughtered, and blood and breast muscles samples were collected. The results showed that there was no significant difference in feed intake, body weight gain, or feed to gain ratio among treatments (P > 0.05). Dietary SY, Met-Se, and Nano-Se supplementation increased the activity of glutathione peroxidase in serum and breast muscles and decreased the concentration of malondialdehyde in serum and carbonyl in breast muscles compared with the SS group (P < 0.05). Moreover, SY, Met-Se, and Nano-Se supplementation increased pH45min, total protein solubility, and myofibrillar protein solubility, as well as decreased the shear force value compared with the SS group (P < 0.05). In addition, birds in the SY and Met-Se groups exhibited lower cooking loss compared with the SS group (P < 0.05). In conclusion, organic Se and Nano-Se supplementation resulted in an improvement of antioxidant capacity and meat quality in local Chinese Subei chickens relative to inorganic Se.  相似文献   
7.
8.
Lewy bodies are intracellular fibrillar inclusions composed of alpha-synuclein. They constitute the pathological hallmark of Parkinson's disease, dementia with Lewy bodies, and other neurodegenerative diseases. Although the majority of Lewy bodies are stained for ubiquitin by immunohistochemistry, the substrate for this modification is poorly understood. Insoluble, urea-soluble alpha-synuclein was separated from soluble fractions and subjected to two-dimensional gel electrophoresis to further characterize pathogenic alpha-synuclein species from disease brains. By using this approach, we found that in sporadic Lewy body diseases a highly modified, disease-associated 22-24-kDa alpha-synuclein species is ubiquitinated. Conjugation of one, two, and, to a lesser extent, three ubiquitins was detected. This 22-24-kDa alpha-synuclein species represents partly phosphorylated protein. Furthermore, no generalized impairment of the proteolytic activity of the proteasome was detected in brain regions with Lewy body pathology. Because unmodified alpha-synuclein is degraded by the proteasome in a ubiquitin-independent manner, these data suggest that accumulation of modified 22-24-kDa alpha-synuclein is a disease-specific event which may overwhelm the proteolytic system, leading to aberrant ubiquitination. Accordingly, carboxyl-terminal-truncated alpha-synuclein, presumably the result of aberrant proteolysis, is found only in association with alpha-synuclein aggregates.  相似文献   
9.
10.
Present study was intended with the aim to document the pre-existence traditional knowledge and ethnomedicinal uses of plant species in the Palas valley. Data were collected during 2015–2016 to explore plants resource, their utilization and documentation of the indigenous knowledge. The current study reported a total of 65 medicinal plant species of 57 genera belonging to 40 families. Among 65 species, the leading parts were leaves (15) followed by fruits (12), stem (6) and berries (1), medicinally significant while, 13 plant species are medicinally important for rhizome, 4 for root, 4 for seed, 4 for bark and 1 each for resin. Similarly, thirteen species were used as a whole while twelve species as partial for medicinal purpose. Further, it is concluded that every part of plants such as bulb, rhizome, roots, barks, leaves, flowers, fruit and seed were used for various ailments. Moreover, among 65 plants species, 09 species are threatened and placed into Endangered (EN) and Least Concern (LC) categories of IUCN. The recorded data are very useful and reflects the significance of the Palas valley as medicinal plants resource area.  相似文献   
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