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71.
To develop a cold disinfestation treatment for the fruit fly Bactrocera invadens Drew, Tsuruta & White (Diptera: Tephritidae) that is rapidly spreading across Africa, research was conducted in Nairobi, Kenya, using flies from a laboratory culture and 'Valencia' orange (Citrus sinensis L. Osbeck) as the host. The developmental rate of B. invadens in Valencia oranges was determined at 28 degrees C, and the third instar was found to be the least susceptible of the egg and larval life stages to cold treatment at 1.1 degrees C in oranges. When 22,449 B. invadens third instars were exposed in oranges to a cold treatment with an approximate midpoint of 1.1 +/- 0.5 degrees C, the results suggested that a period of 16 d would be worthwhile verifying on a larger scale in oranges. Results from the first replicate of 16,617 larvae showed no survivors, but the second replicate of 23,536 larvae had three survivors. Because a longer cold treatment based on a mean temperature of 1.1 degrees C would create logistical difficulties for some export markets, further replicates were conducted at an approximate midpoint of 0.5 degrees C and at mean hourly maximum of 0.9 +/- 0.5 degrees C, for 16 d. After three replicates, in which 65,752 B. invadens third instars in total were treated with no survivors, the Japanese requirement of 99.99% mortality at the 95% confidence level was surpassed. The following treatment protocol for B. invadens larvae in oranges can therefore be recommended: fruit pulp to be maintained at temperatures of 0.9 degrees C or lower for 16 consecutive days.  相似文献   
72.
Vanadium has been reported to have broad pharmacological activity both in vitro and in vivo. Vanadium compound, sodium orthovanadate, Na3VO4, is well known for its hypoglycaemic effects. However, Na3VO4 exerts these effects at relatively high doses (0.6 mg/ml) and exhibit several toxic effects. In the present study lower doses of Na3VO4 (0.2 mg/ml) are combined with Trigonella foenum graecum seed powder (TSP), another hypoglycaemic agent, to reduce its toxicity without compromising its antidiabetic potential. The efficacy of the lower doses of Na3VO4 has been investigated in restoring the altered glucose metabolism and histological structure in the sciatic nerves in 21 and 60 days alloxan diabetic rats. A portion of the glucose was found to be channelled from the normal glycolytic route to polyol pathway, evident by the reduced hexokinase activity and increased polyol pathway enzymes aldose reductase and sorbitol dehydrogenase activity causing accumulation of sorbitol and fructose in diabetic conditions. Ultrastructural observation of the sciatic nerve showed extensive demylination and axonal loss after eight weeks of diabetes induction. Blood glucose levels increased in diabetic rats were normalized with the lower dose of vanadium and Trigonella treatment. The treatment of the diabetic rats with vanadium and Trigonella prevented the activation of the polyol pathway and sugar accumulations. The sciatic nerves were also protected against the structural abnormalities found in diabetes with Trigonella foenum graecum as well as Na3VO4. Results suggest that lower doses of Na3VO4 may be used in combination with TSP as an efficient antidiabetic agent to effectively control the long-term complications of diabetes in tissues like peripheral nerve.  相似文献   
73.
The overwhelming majority of DNA photoproducts in UV-irradiated spores is a unique thymine dimer called spore photoproduct (SP, 5-thymine-5,6-dihydrothymine). This lesion is repaired by the spore photoproduct lyase (SP lyase) enzyme that directly reverts SP to two unmodified thymines. The SP lyase is an S-adenosylmethionine-dependent iron-sulfur protein that belongs to the radical S-adenosylmethionine superfamily. In this study, by using a well characterized preparation of the SP lyase enzyme from Bacillus subtilis, we show that SP in the form of a dinucleoside monophosphate (spore photoproduct of thymidilyl-(3'-5')-thymidine) is efficiently repaired, allowing a kinetic characterization of the enzyme. The preparation of this new substrate is described, and its identity is confirmed by mass spectrometry and comparison with authentic spore photoproduct. The fact that the spore photoproduct of thymidilyl-(3'-5')-thymidine dimer is repaired by SP lyase may indicate that the SP lesion does not absolutely need to be contained within a single- or double-stranded DNA for recognition and repaired by the SP lyase enzyme.  相似文献   
74.

Introduction

Alcohol use is one of the leading modifiable morbidity and mortality risk factors among young adults.

Study Design

2 parallel-group randomized controlled trial with follow-up at 1 and 6 months.

Setting/Participants

Internet based study in a general population sample of young men with low-risk drinking, recruited between June 2012 and February 2013.Intervention: Internet-based brief alcohol primary prevention intervention (IBI). The IBI aims at preventing an increase in alcohol use: it consists of normative feedback, feedback on consequences, calorific value alcohol, computed blood alcohol concentration, indication that the reported alcohol use is associated with no or limited risks for health. Intervention group participants received the IBI. Control group (CG) participants completed only an assessment.

Main Outcome Measures

Alcohol use (number of drinks per week), binge drinking prevalence. Analyses were conducted in 2014–2015.

Results

Of 4365 men invited to participate, 1633 did so; 896 reported low-risk drinking and were randomized (IBI: n = 451; CG: n = 445). At baseline, 1 and 6 months, the mean (SD) number of drinks/week was 2.4(2.2), 2.3(2.6), 2.5(3.0) for IBI, and 2.4(2.3), 2.8(3.7), 2.7(3.9) for CG. Binge drinking, absent at baseline, was reported by 14.4% (IBI) and 19.0% (CG) at 1 month and by 13.3% (IBI) and 13.0% (CG) at 6 months. At 1 month, beneficial intervention effects were observed on the number of drinks/week (p = 0.05). No significant differences were observed at 6 months.

Conclusion

We found protective short term effects of a primary prevention IBI.

Trial Registration

Controlled-Trials.com ISRCTN55991918  相似文献   
75.
Cryptosporidium , a protozoan parasite that causes watery diarrhea, is found worldwide and is common in areas with low water hygiene. In February 2014, 866 stool samples were collected from the inhabitants of 2 rural areas in White Nile State, Sudan. These stool samples were assessed by performing modified acid-fast staining, followed by examination under a light microscope. The overall positive rate of Cryptosporidium oocysts was 13.3%. Cryptosporidium oocysts were detected in 8.6% stool samples obtained from inhabitants living in the area having water purification systems and in 14.6% stool samples obtained from inhabitants living in the area not having water purification systems. No significant difference was observed in the prevalence of Cryptosporidium infection between men and women (14.7% and 14.1%, respectively). The positive rate of oocysts by age was the highest among inhabitants in their 60s (40.0%). These findings suggest that the use of water purification systems is important for preventing Cryptosporidium infection among inhabitants of these rural areas in Sudan.  相似文献   
76.
The major DNA photoproduct in UV-irradiated Bacillus subtilis spores is the thymine dimer named spore photoproduct (SP, 5-(alpha-thyminyl)-5,6-dihydrothymine). The SP lesion has been found to be efficiently repaired by SP lyase (SPL) a very specific enzyme that reverses the SP to two intact thymines, at the origin of the great resistance of the spores to UV irradiation. SPL belongs to a superfamily of [4Fe-4S] iron-sulfur enzymes, called "Radical-SAM." Here, we show that the single substitution of cysteine 141 into alanine, a residue fully conserved in Bacillus species and previously shown to be essential for spore DNA repair in vivo, has a major impact on the outcome of the SPL-dependent repair reaction in vitro. Indeed the modified enzyme catalyzes the almost quantitative conversion of the SP lesion into one thymine and one thymine sulfinic acid derivative. This compound results from the trapping of the allyl-type radical intermediate by dithionite, used as reducing agent in the reaction mixture. Implications of the data reported here regarding the repair mechanism and the role of Cys-141 are discussed.  相似文献   
77.
Increased environmental pollution and unhealthy lifestyle are blamed for escalated chronic diseases. Exposure to aflatoxins was recently suggested to have a role in the increased incidence of type 2 diabetes mellitus. Diet modification and consumption of different functional food are now gaining attention, especially in diabetes management. This study investigates the effect of a diet containing barley microgreen against diabetes induced by streptozotocin with or without aflatoxin administration in rats. Barley microgreen was rich in 3′-Benzyloxy-5,6,7,4′-tetramethoxyflavone (48.8% of total) followed by 5β,7βH,10α-Eudesm-11-en-1α-ol (18.46%). Streptozotocin injection and/or aflatoxin administration significantly elevated glucose level, decreased insulin level, decreased β-cell function, deteriorated liver and kidney function parameters, and induced oxidative stress in the liver. Histopathology revealed irregular small-sized islets and decreased area % of insulin-positive beta cells in the pancreas, hepatic degeneration, nephropathy, and neuropathy in diabetic and/or aflatoxin administered rats compared to control. Barley microgreen diet fed to diabetic rats with or without aflatoxin alleviated all evaluated parameters. Barley microgreen diet also ameliorated the toxic effect of aflatoxin. In conclusion, exposure to aflatoxin aggravated diabetes and its complication. The incorporation of barley microgreen in the diet was able to control type 2 diabetes mellitus and the improved outcomes observed with barley microgreen treatments involved or occurred in conjunction with improved biomarkers of oxidative stress.  相似文献   
78.
Spermatogenesis results from a balance between proliferation and apoptosis. An alteration in this balance could lead to testicular diseases such as testicular tumour or infertility. Apoptosis seem to be important in regulating the processes of spermatogenesis since 60 to 75% of germ cells do not reach the spermatozoa stage. The various molecules of the apoptotic cascade have been detected in rodent or human germ cells, such as effector caspases and upstream proteins from cell death receptor or mitochondrial pathways. One or several different pathways may be involved in the germ cell apoptotic process triggered physiologically, by hormonal deprivation, or by chemical or physical inducers. Finally, caspases appear to play a role in various testicular diseases (particularly infertility).  相似文献   
79.
There is increasing evidence that hyperoxia, particularly at the time of birth, may result in neurological injury, in particular to the susceptible vasculature of these tissues. This study was aimed at determining whether overexpression of extracellular superoxide dismutase (EC-SOD) is protective against brain injury induced by hyperoxia. Transgenic (TG) mice (with an extra copy of the human extracellular superoxide dismutase gene) and wild-type (WT) neonate mice were exposed to hyperoxia (95% of F(i) o(2) ) for 7 days after birth versus the control group in room air. Brain positron emission tomography (PET) scanning with fludeoxyglucose (FDG) isotope uptake was performed after exposure. To assess apoptosis induced by hyperoxia exposure, caspase 3 ELISA and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were performed. Quantitative western blot for the following inflammatory markers was performed: glial fibrillary acidic protein, ionized calcium-binding adaptor molecule 1, macrophage-inhibiting factor, and phospho-AMP-activated protein kinase. PET scanning with FDG isotope uptake showed significantly higher uptake in the WT hyperoxia neonate brain group (0.14 ± 0.03) than in both the TG group (0.09 ± 0.01) and the control group (0.08 ± 0.02) (P< 0.05). Histopathological investigation showed more apoptosis and dead neurons in hippocampus and cerebellum brain sections of WT neonate mice after exposure to hyperoxia than in TG mice; this finding was also confirmed by TUNEL staining. The caspase 3 assay confirmed the finding of more apoptosis in WT hyperoxia neonates (0.814 ± 0.112) than in the TG hyperoxic group (0.579 ± 0.144) (P < 0.05); this finding was also confirmed by TUNEL staining. Quantitative western blotting for the inflammatory and metabolic markers showed significantly higher expression in the WT group than in the TG and control groups. Thus, overexpression of EC-SOD in the neonate brain offers significant protection against hyperoxia-induced brain damage.  相似文献   
80.
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