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91.
A study was undertaken to assess the phytotoxicity of citronellal, an oxygenated monoterpenoid with an aldehyde group, towards some weedy species [Ageratum conyzoides L., Chenopodium album L., Parthenium hysterophorus L., Malvastrum coromandelianum (L.), Garcke, Cassia occidentalis L. and Phalaris minor Retz.]. A significant effect on weed emergence and early seedling growth was observed in a dose-response based laboratory bioassay in a sand culture. Emergence of all test weeds was completely inhibited at 100 micro/g sand content of citronellal. Seeds of A. conyzoides and P. hysterophorus failed to emerge even at 50 microg/g content. Root length was inhibited more compared to shoot length. The failure of root growth was attributed to the effect of citronellal on the mitotic activity of growing root tips cells as ascertained by the onion root tip bioassay. At 2.5 mM treatment of citronellal, mitosis was completely suppressed and at higher concentrations cells showed various degrees of distortion and were even enucleated. The post-emergent application of citronellal also caused visible injury in the form of chlorosis and necrosis, leading to wilting and even death of test weeds. Among the test weeds, the effect was severe on C. album and P. hysterophorus. There was loss of chlorophyll pigment and reduction in cellular respiration upon citronellal treatment indicating the impairment of photosynthetic and respiratory metabolism. Scanning electron microscopic studies in C. occidentalis leaves upon treatment of citronellal revealed disruption of cuticular wax, clogging of stomata and shrinkage of epidermal cells at many places. There was a rapid electrolyte leakage in the leaf tissue upon exposure to citronellal during the initial few hours. In P. minor electrolyte leakage in response to 2 mM citronellal was closer to the maximum leakage that was obtained upon boiling the tissue. The rapid ion leakage is indicative of the severe effect of citronellal on the membrane structure and loss of membrane integrity. In all, the study concludes that citronellal causes a severe phytotoxicity on the weeds.  相似文献   
92.
Cadmium (Cd) is a non-redox toxic heavy metal present in the environment and induces oxidative stress in plants. We investigated whether exogenous nitric oxide (NO) supplementation as sodium nitroprusside (SNP) has any ameliorating action against Cd-induced oxidative damage in plant roots and thus protective role against Cd toxicity. Cd treatment (50 or 250 μM) alone or in combination with 200 μM SNP was given to hydroponically grown wheat roots for a short time period of 24 h and then these were shifted to distilled water to observe changes in levels of oxidative markers (lipid peroxidation, H2O2 content and electrolyte leakage). Supplementation of Cd with SNP significantly reduced the Cd-induced lipid peroxidation, H2O2 content and electrolyte leakage in wheat roots. It indicated a reactive oxygen species (ROS) scavenging activity of NO. However, even upon removal of Cd-treatment solution, the levels of oxidative markers increased during 24 h recovery stage and later at 48 h these decreased. Cd treatment resulted in an upregulation of activities of antioxidant enzymes—superoxide dismutase (SOD, 1.15.1.1), guaiacol peroxidase (GPX, 1.11.1.7), catalase (CAT, 1.11.1.6), and glutathione reductase (GR, 1.6.4.2). SNP supply resulted in a reduction in Cd-induced increased activities of scavenging enzymes. The protective role of exogenous NO in decreasing Cd-induced oxidative damage was also evident from the histochemical localization of lipid peroxidation, plasma membrane integrity and superoxides. The study concludes that an exogenous supply of NO protects wheat roots from Cd-induced toxicity.  相似文献   
93.
Anticholinergics, specifically antimuscarinic agents, are the most common medications prescribed for overactive bladder (OAB). The most common side effects of these agents are dry mouth and constipation, although other more concerning effects include changes in blood pressure, pulse rate, or heart rhythm when treatment is initiated. Herbal treatments are an increasingly popular alternative for treating OAB. A 2002 survey of US adults aged ≥ 18 years conducted by the Centers for Disease Control and Prevention indicated that 74.6% of those with OAB had used some form of complementary and alternative medicine. The World Health Organization estimates that 80% of the world’s population presently uses herbal medicine for some aspect of primary health care. Women were more likely than men to use complementary and alternative medicine. The authors review the most commonly used herbal medications for OAB.Key words: Overactive bladder, Herbal medicine, Gosha-jinki-gan, Hachi-mi-jio-gan, Buchu (Barosma betuline), Cleavers (Galium aparine), Cornsilk (Zea mays), Horsetail (Equisetum), Ganoderma lucidum, Resinferatoxin, CapsaicinOveractive bladder (OAB) is defined by the International Continence Society as a syndrome that includes urgency, with or without urge incontinence, frequency, and nocturia. The prevalence of OAB is estimated to range between 9% and 16%, depending on the population studied.13 As symptoms of OAB increase with age, they can negatively impact quality of life (QoL).The cost of treating OAB is estimated to be approximately $12 billion annually in the United States.4 This estimate accounts for the direct cost of management, including protective undergarments, bedside commodes, and medical treatment, as well as indirect costs, such as those resulting from urinary tract infections and falls due to urgency and nocturia. There are also additional intangible costs that cannot be estimated such as pain, suffering, and poor QoL.The negative impact on health and the sense of well-being as well as the impairment in the ability to perform activities of daily living, has been well-documented. For example, elderly patients with OAB and subsequent incontinence are more likely to be admitted to nursing homes. Thom and colleagues reported a twofold increased risk of admission to a nursing facility for patients with incontinence.5 Urinary incontinence can also lead to anxiety, negative self-image, and isolation.4 Other problems associated with OAB include skin ulcerations and urinary tract infections. Nocturia is common with OAB and ranks among the most bothersome of lower urinary tract symptoms.6 In addition to sleep interruption and resulting fatigue, patients with nocturia may be more likely to suffer from falls and fractures, which are associated with high mortality in elderly patients. Approximately 33% of elderly people do not survive beyond 1 year after a hip fracture.7The impact of OAB was clearly reported in the National Overactive Bladder Evaluation (NOBLE) study.8 The NOBLE study represented a computer-assisted telephone interview survey that used health-related QoL (HRQoL) questionnaires to compare continent OAB patients, with incontinent OAB patients, and control groups in a nested case-control fashion. In this study, OAB was associated with lower QoL scores, higher scores on depression, and poorer sleep quality when compared with control subjects.8 Note that, although the prevalence of OAB increases with age, it should not be considered a normal consequence of aging.Anticholinergics, specifically antimuscarinic agents, represent the most common medications prescribed for OAB. The most common side effects are dry mouth and constipation.9,10 Other more concerning side effects include changes in blood pressure, pulse rate, or heart rhythm when treatment is initiated. Additional adverse events (AEs) include memory loss, cognitive impairment, and balance problems. Thus, alternative therapies not involving standard medications and their associated risks are sought by patients to alleviate symptoms of OAB.Herbal treatments represent an increasingly popular alternative for treating OAB. A 2002 survey of US adults aged ≥ 18 years conducted by the Centers for Disease Control and Prevention indicated 74.6% of those with OAB had used some form of complementary and alternative medicine. The World Health Organization estimates that 80% of the world’s population presently uses herbal medicine for some aspect of primary health care. Women were more likely than men to use complementary and alternative medicine.10,11 We review the most commonly used herbal medications used for OAB.  相似文献   
94.
95.
Psoriasis is one of the most prevalent chronic inflammatory diseases of the skin. The Wnt pathways have been documented to play essential role in stem cell self-renewal and keratinocyte differentiation in the skin. Antagonizing the Wnt5a protein would emerge as a novel therapeutics in psoriasis treatment. In this view, we have developed and characterized series of compounds by attaching varied tertiary alkyloxy carbonyl groups at the N-terminal end of the hexapeptide (Met-Asp-Gly-Cys-Glu-Leu) bestowed to inhibit Wnt/Ca2+ signaling in psoriasis. Hexapeptide compound with 1,1-diphenylethoxy carbonyl group attached to N-terminal end of hexapeptide demonstrated highest binding affinity amongst all the evaluated compounds. The compound identified in the study can be subjected further for in vitro and in vivo studies for ADMET properties.  相似文献   
96.

Background

Fevers of unknown origin constitute a substantial disease burden in Southeast Asia. In majority of the cases, the cause of acute febrile illness is not identified.

Methods

We used MassTag PCR, a multiplex assay platform, to test for the presence of 15 viral respiratory agents from 85 patients with unexplained respiratory illness representing six disease clusters that occurred in Cambodia between 2009 and 2012.

Results

We detected a virus in 37 (44%) of the cases. Human rhinovirus, the virus detected most frequently, was found in both children and adults. The viruses most frequently detected in children and adults, respectively, were respiratory syncytial virus and enterovirus 68. Sequence analysis indicated that two distinct clades of enterovirus 68 were circulating during this time period.

Conclusions

This is the first report of enterovirus 68 in Cambodia and contributes to the appreciation of this virus as an important respiratory pathogen.
  相似文献   
97.

Background

Wild birds are an important but to some extent under-studied reservoir for emerging pathogens. We used unbiased sequencing methods for virus discovery in shorebird samples from the Delaware Bay, USA; an important feeding ground for thousands of migratory birds.

Findings

Analysis of shorebird fecal samples indicated the presence of a novel astrovirus and coronavirus. A sanderling sample yielded sequences with distant homology to avian nephritis virus 1, an astrovirus associated with acute nephritis in poultry. A ruddy turnstone sample yielded sequences with homology to deltacoronaviruses.

Conclusions

Our findings highlight shorebirds as a virus reservoir and the need to closely monitor wild bird populations for the emergence of novel virus variants.  相似文献   
98.
Despite recent improvement in implant survival rates, there remains a significant demand for enhancing the long-term clinical efficacy of titanium (Ti) implants, particularly for the prevention of peri-implantitis. Bioactive substances such as antimicrobial peptides are emerging as effective alternatives for contemporary antimicrobial agents used in dental health care. Current research work was focused to use laterosporulins that are non-haemolytic cationic antimicrobial peptides from Brevibacillus spp. for coating commercially available Ti discs. The coated Ti surfaces were evaluated in vitro for biofilm formation by two dental plaque isolates Streptococcus gordonii strain DIGK25 and S. mutans strain DIGK119 as representatives of commensal and pathogenic streptococci respectively. The biofilm inhibition was ascertained with replicated experiments on hydroxyapatite discs and confirmed by florescence microscopy. The laterosporulin coated Ti discs showed significantly reduced biofilm formation by oral streptococci and displayed promising potential to enhance the antibacterial surface properties. Such improvised Ti surfaces may curb the menace of oral streptococcal biofilm formation on dental implants and the associated implant failures.  相似文献   
99.
Papadimitriou  George  Lyons  Eric  Wang  Cong  Thareja  Komal  Tanaka  Ryan  Ruth  Paul  Rodero  Ivan  Deelman  Ewa  Zink  Michael  Mandal  Anirban 《Cluster computing》2022,25(4):2873-2891
Cluster Computing - Computational science depends on complex, data intensive applications operating on datasets from a variety of scientific instruments. A major challenge is the integration of...  相似文献   
100.
Phytochemistry Reviews - Alstonia scholaris (L.) R. Br (Apocynaceae), a tropical tree native to Indian subcontinent, Australasia, and Malay Peninsula is well documented in Traditional Chinese...  相似文献   
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