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21.
Diabetes mellitus (DM) is closely associated with male infertility and sexual dysfunction. Recent data indicate that the proinsulin C-peptide (CP) exerts important physiological effects and shows the characteristics of an endogenous peptide hormone. So, this study was done to investigate the effect of C-peptide with or without insulin treatment on testicular function and architecture in diabetic rats. Rats were divided into the following groups: control, diabetic, and diabetic groups treated with either CP alone or combined with insulin. Tested parameters included, estimation of serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, and glucose levels, testicular samples for histopathology and estimation of malondialdehyde (MDA), total antioxidant capacity (TAC), and B-cell leukemia/lymphoma-2 (BCL-2) levels as well as sperm count and motility. Results showed that DM caused a severe alteration in hormonal profile and reduced sperm parameters along with increased MDA and decrease in both TAC and BCL-2 levels. CP alone or with insulin treatment efficiently reversed all the negative effects of DM on rat testes, with maximum improvement in the combined regimen. Proposed mechanisms may involve its hypoglycemic, antioxidant, and antiapoptotic properties. Thus, CP could substitute for or better combined with insulin to prevent or retard diabetic-induced testicular dysfunction.  相似文献   
22.

Aim

The aim of this study was to determine the incidence of TNBC in Kuwait, to analyze the clinicopathologic features and prognosis of this type of breast cancer, and compare it with reports from other regions of the world.

Background

Triple negative breast cancer (TNBC) is defined as a subtype that is negative for estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2). There is a growing evidence of the heterogeneity of such entity on the molecular level that may cause discrete outcomes.

Methods

We analyzed the clinicopathologic features of 363 TNBC cases which were diagnosed in Kuwait from July 1999 to June 2009. The disease-free survival (DFS) and overall survival (OS) were analyzed by Kaplan–Meier method. Comparison was done with reports from USA, Europe, Middle and Far East.

Results

Among 2986 patients diagnosed with breast cancer in Kuwait, 363 patients (12.2%) were TNBC. The median age was 48 years, 57.2% had lymph nodes (LN) metastasis, 56.9% were of grade III tumor and 41.9% had stage II disease. 81% developed recurrences and 75% of deaths occurred by 2.5 years after treatment. There is marked variation of clinicopathologic features according to country of patients’ cohort.

Conclusion

The incidence of TNBC in our study is similar to other studies. TNBC patients showed an early major recurrence surge peaking at approximately year 2.5. Regional variation of clinicopathologic features indicates a need for molecular studies to define underlying molecular features and its impact on survival.  相似文献   
23.
Secondary hyperparathyroidism and trace elements’ metabolism disturbances are common, important, and treatable complications of chronic renal failure (CRF).The relation between parathyroid hormone (PTH) and some trace elements in CRF patients on hemodialysis is still not completely elucidated. The aim of this work is to determine the serum levels of PTH and the trace elements zinc (Zn) and magnesium (Mg) in children with CRF under hemodialysis. The relation between PTH and those trace elements will be investigated. The study included 24 children (15 males and nine females) with CRF on regular hemodialysis. Also, 15 healthy age-matched children were included as control group. Serum levels of PTH, zinc, and magnesium were determined in all cases and controls. PTH and magnesium levels in patients were significantly higher than controls. Serum zinc levels were significantly lower than controls. There was a significant negative correlation between serum levels of PTH and zinc as well as an insignificant negative correlation between PTH and serum magnesium in CRF patients. Elevated PTH may play a role in the pathogenesis of hypozincemia. However, this is another negative report on the relation between PTH and serum Mg in children with CRF.  相似文献   
24.
Biomphalaria alexandrina snails play an indispensable role in transmission of schistosomiasis. Infection rates in field populations of snails are routinely determined by cercarial shedding neglecting prepatent snail infections, because of lack of a suitable method for diagnosis. The present study aimed at separation and quantification of oxalic, malic, acetic, pyruvic, and fumaric acids using ion-suppression reversed-phase high performance liquid chromatography (HPLC) to test the potentiality of these acids to be used as diagnostic and therapeutic biomarkers. The assay was done in both hemolymph and digestive gland-gonad complex (DGG) samples in a total of 300 B. alexandrina snails. All of the studied acids in both the hemolymph and tissue samples except for the fumaric acid in hemolymph appeared to be good diagnostic biomarkers as they provide not only a good discrimination between the infected snails from the control but also between the studied stages of infection from each other. The most sensitive discriminating acid was malic acid in hemolymph samples as it showed the highest F-ratio. Using the Z-score, malic acid was found to be a good potential therapeutic biomarker in the prepatency stage, oxalic acid and acetic acid in the stage of patency, and malic acid and acetic acid at 2 weeks after patency. Quantification of carboxylic acids, using HPLC strategy, was fast, easy, and accurate in prediction of infected and uninfected snails and possibly to detect the stage of infection. It seems also useful for detection of the most suitable acids to be used as drug targets.  相似文献   
25.
Hepatic injury by acetaminophen (APAP) has been extensively studied, although the alterations of renal functions and arterial blood pressure (ABP) after APAP exposure are still uncertain, and the impact of Nigella sativa oil (NSO) in this case is poorly defined. Sixty adult male albino rats were involved in two sets of experiments. The first was exposed to a single high dose of APAP (2.5 g/kg) orally preceded by 4 ml NSO/kg orally, while the second received 750 mg APAP/kg/day orally for seven consecutive days and was pretreated with 2 ml NSO/kg/day. Proximal tubular injury was assessed by laboratory and histological studies, and arterial blood pressure was recorded in all animals. In both experiments, urinary α-glutathione S-transferase and neutral endopeptidase, and microproteinuria were dramatically increased early indicating glomerulus and proximal tubule dysfunction that was mediated by raising 8-isoprostanes. Concomitantly, urinary albumin, total protein, creatinine, urea, glomerular filtration rate, Na and K levels, plasma creatinine, and urea were all changed significantly after APAP administration. Currently, ABP increased significantly after APAP which was mostly mediated by renal impairment and increased both renin activity and aldosterone secretion. Pretreatment with NSO produced significant normalization of physiological parameters as well as suppression of structural changes. In conclusion, measurement of urinary biomarkers can be considered a powerful tool for early screening of renal injury and alteration of ABP after APAP treatment. Concomitant administration of NSO can counterbalance these detrimental effects.  相似文献   
26.
Twenty-two yeast strains were screened for their efficacy in suppression of root-knot nematode Meloidogyne incognita on Flame Seedless grapevines. The most effective seven strains were chosen to study their effect on nematode population in vitro and in vivo as well as their impact on crop productivity and fruit quality. Data showed that all treatments significantly reduced the number of juveniles in vitro after 24 and 48 h. The highest percentage of nematode mortality was achieved by the application of Pichia gluilliermondii Moh10, Pachytrichospora transvaalensis Y-1240, Candida albicans Moh Y-5 and Geotichum terrestre Y 2162. Similarly, under greenhouse conditions, all treatments significantly reduced the number of juveniles and disease index compared to the untreated plants during both incubation periods (30 and 50 days). Under field conditions, the tested yeast strains as well as Nemacour (nematocide) resulted in a significant reduction (P<0.05) of populations of Meloidogyne incognita compared to the control in two successive seasons tested. The beneficial impact of application of yeast strains was reflected in crop productivity on Flame Seedless grapevines as well as fruit quality. Percentages of vegetative buds, flower buds, shoot length and leaf number were significantly enhanced as a result of application of the different yeast strains and Nemacour. Bunch weight, berry weight and berry numbers were significantly increased by Pachytrichospora transvaalensis Y-1240, Geotichum terrestre Y-2162 and Candida albicans Moh Y-5. Nemacour and other yeast strains did not show any significant differences compared to the infected vines. Percentage of total soluble solids (TSS%) increased by applying all yeast strains, whereas Nemacour treatment gave the highest value of both TSS percent and percentage of acidity and increased anthocyanins in the skin of berries.  相似文献   
27.
Rice husks (RHs) was used as a substrate for biosynthesis of high-value Silica nanoparticles (SiO2NPs). An isolate of Trichoderma harzianum MF780864 (T. harzianum) was isolated and identified based on the Internal Transcribed Spacers (ITS) sequences; it showed the potentiality to induce SiO2NPs in the process of RHs biotransformation. SiO2NPs were produced extracellularly and their size was of about 89 nm. SiO2NPs characterized by oval, rod and cubical particles by using Transmission Electron Microscope (TEM).The Fourier transform infrared spectroscopy (FTIR) confirmed the presence of various functional groups of biomolecules and capping protein, encapsulating SiO2NPs. Water and fish samples were collected from private fish farms in El-Sharkia Governorate, Egypt. Lead (Pb) was detected from water and fish samples at its highest concentration at about 0.088 mg/L. The adsorption capacity of Pb by SiO2NPs was evaluated by testing different concentrations of SiO2NPs viz. 1, 2, and 3 mg/L, wherein 1 mg/L revealed the highest Pb adsorption efficiency. Within laboratory trials, the results indicated that highest Pb adsorption efficiency revealed through the increasing of SiO2NPs concentrations until 120 h. In vivo trial that lasted for 8 weeks, Nile tilapia (Oreochromis niloticus) (29.78 ± 0.36 g body weight) supplemented with 0.088 mg/L Pb was divided into four experimental groups having three replicates (15 fish/replicate; 45 fish/group). The results showed that SiO2NPs supplementation through water revealed significant increase in growth and hematological parameters of O. niloticus. Moreover, enhancement of antioxidant capacity (TAC), and immune related gene expression of IL-1β were increased in the presence of SiO2NPs compared with the groups of Pb exposure. Moreover, Pb residue level in fish muscles was noticeably decreased in the SiO2NPs treated groups. Thus, this research opens up other possibilities in the field of using SiO2NPs as a lead adsorbent for water bioremediation.  相似文献   
28.
Several antioxidants namely ascorbic acid, salicylic acid, sodium benzoates, thiouria and catechol were used as seed treatment and foliar spraying to reduce the incidence of root and pod rot diseases of peanut caused by (Fusarium oxysporum, Fusarium solani and Fusarium moniliforme) as well as to determine of phenolic compounds and oxidative enzymes in the treated plants. Each antioxidant was used at different concentrations (2, 4, 6 and 8 mM) against tested pathogenic fungi in vitro. All antioxidants at 8 mM showed the greatest reduction of mycelial growth of the pathogens. In greenhouse experiments, treated seeds (Giza 5 cv.) or foliar spraying of peanut plants after 30 and 60 days from planting date with each antioxidant at 8 mM reduced severity of both diseases. The treated plants with antioxidants increased accumulation of phenolic compounds and activity levels of oxidative enzymes (catalase, peroxidase and polyphenoloxidase) in infected plants compared to healthy plants.

http://zoobank.org/urn:lsid:zoobank.org:pub:AF539C90-4B38-4BFE-B77B-5F2A5D764D7A  相似文献   

29.
Novel photoluminescent nanocomposite sheets were prepared for simple commercial manufacturing of transparent and luminous photochromic smart windows. A simple physical integration of lanthanide-doped strontium aluminium oxide (LdSAO) nanoparticles into recycled polyethylene (PE) waste produced a smart nanocomposite with persistent phosphorescence and photochromic properties. Because the nanoparticle form of LdSAO is important for developing transparent materials, LdSAO nanoparticles were well dispersed in the PE matrix. Both the morphologies and chemical compositions of the LdSAO nanoparticles and LdSAO-containing luminescent PE sheets were investigated. Both LdSAO-free and photoluminescent PE sheets were colourless in normal daylight. However the LdSAO-containing PE luminescent samples only exhibited a brilliant green colour under ultraviolet (UV) light and a greenish-yellow colour in the dark as verified by Commission Internationale de l'éclairage laboratory parameters. Both absorbance and emission bands were monitored at 377 and 436/517 nm, respectively. The LdSAO-containing PE luminescent sheets were compared with the LdSAO-free sample using both photoluminescence spectroscopy and for their mechanical properties and were found to have improved scratch resistance, UV protection, and superhydrophobic activity. Due to the added LdSAO, photoluminescence, decay, and lifetime spectral tests confirmed its photochromic fluorescence and long-lasting phosphorescence characteristics. The PE@LdSAO nanocomposite sheets displayed UV protection, photostability, hydrophobicity, and excellent durability compared with the blank LdSAO-free PE sheet.  相似文献   
30.
Forgery and low-quality products pose a danger to society. Therefore, there are increasing demands for the production of easy-to-recognize and difficult-to-copy anticounterfeiting materials. Products with smart photochromic and fluorescence properties can change colour and emission spectra responding to a light source. In this context, we devised a straightforward preparation of a luminescent polyvinyl alcohol/carboxymethyl cellulose (PVA/CMC) nanocomposite to function as a transparent labelling film. The lanthanide-doped aluminate (LdA) was prepared in the nanoparticle form to indicate diameters of 35–115 nm. Different ratios of the LdA were physically dispersed in the PVA/CMC nanocomposite label film to provide photochromic, ultraviolet protection, antimicrobial activity, and hydrophobic properties. Fluorescence peaks were detected at 365 and 519 nm to indicate a colour change to green. As a result of increasing the phosphor ratio, improved superhydrophobic activity was achieved as the contact angle was increased from 126.1° to 146.0° without affecting the film's original physical and mechanical properties. Both ultraviolet (UV) light protection and antibacterial activity were also investigated. The films showed a quick and reversible photochromic response without fatigue. The current strategy reported the development of a photochromic smart label that is transparent, cost effective, and flexible. As a result, numerous anticounterfeiting products can benefit from the current label for a better market. LdA-loaded PVA/CMC films demonstrated antibacterial activity between poor, good, very good, and outstanding as the percentage of LdA in the film matrix increased. The current film can be applied as a transparent photochromic security barcode for anticounterfeiting applications and smart packaging.  相似文献   
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