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Parkinson's disease is an environmentally influenced, neurodegenerative disease of unknown origin that is characterized by the progressive loss of dopaminergic neurons in the substantia nigra pars compacta of the brain. Arsenic is an environmental contaminant found naturally in ground water, industrial waste, and fertilizers. The initial goal of the present study was to determine if a mixture of arsenite (As(+3)) and dopamine (DA) could cause enhanced degeneration of dopaminergic neuronal cells. Additional goals were to determine the mechanism (apoptosis or necrosis) of As- and DA-induced cell death and if death could be attenuated by antioxidants. The cell culture model employed was the SH-SY5Y neuroblastoma cell line that has been shown to possess differentiated characteristics of dopaminergic neurons. The results demonstrated that a mixture of As(+3) and DA was synergistic in producing the death of the SH-SY5Y cells when compared with exposure to either agent alone. A mixture of 10muM As(+3) and 100muM DA produced almost a complete loss of cell viability over a 24-h period of exposure, whereas, each agent alone had minimal toxicity. It was shown that necrosis, and not apoptosis, was the mechanism of cell death produced by exposure of the SH-SY5Y cells to the mixture of As(+3) and DA. It was also demonstrated that the antioxidants, N-acetylcysteine, and Sulforaphane, attenuated the toxicity of the mixture of As(+3) and DA to the SH-SY5Y cells. This study provides initial evidence that As(+3) and DA synergistically can cause enhanced toxicity in cultured neuronal cells possessing dopaminergic differentiation.  相似文献   
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A new dihydroflavonol, songaricol ( 1) and seven known flavonoids, ayamenin A ( 2), irisflavone A ( 3), 5,7-dihydroxy-2',6-dimethoxyisoflavone ( 4), irilin B ( 5), 5,3'-dihydroxy-7,8,2'-trimethoxyisoflavone ( 6) and irisoid A ( 7) were isolated from rhizome and roots of IRIS SONGARICA. Structure elucidation of 1 was achieved through extensive NMR and circular dichroism techniques. Compounds 1, 5 and 7 showed antioxidant activity in HL-60 cells (IC50 values of 21, 11 and 3.8 microg/mL), whereas 2, 5 and the previously isolated irisone B were able to show estrogenic response (EC50 values of 305.5, 159.7 and 322.0 microg/mL) in yeast cells expressing human estrogen receptor (ER-alpha).  相似文献   
45.
Evaluation of Alstonia scholaris leaves for broncho-vasodilatory activity   总被引:1,自引:0,他引:1  
The present study demonstrates that the ethanol extract of Alstonia scholaris (Apocynaceae) leaves induced pronounced bronchodilatory activity in anaesthetized rats with the probable involvement of prostaglandins. However, in vitro preparations of guinea-pig trachea did not confirm this property, indicating that bronchodilation is not due to the direct tracheal smooth muscle relaxation. The vasodilatory activity of the extract was independent of adrenergic or muscarinic receptors or prostaglandins but was mainly via endothelial-derived relaxing factor, nitric oxide. The extract inhibited the spontaneous movements of rabbit jejunum and contractile effects of acetylcholine and histamine on guinea-pig ileum. Additionally, the extract caused marked reduction of barium chloride-, potassium chloride- and calcium chloride-induced contraction on guinea-pig ileum and pulmonary artery, implying a direct interference of plant extract with the influx of calcium ions into cells. However, the extract has no detectable effect on mobilization of intracellular calcium. These results coupled with the in vivo effects of ethanol extract reveal that the Alstonia scholaris leaves possess broncho-vasodilatory activity mediated presumably by prostaglandins, calcium antagonism and endothelium-derived relaxing factor(s).  相似文献   
46.
Introduction: The physiologic importance of fast CO2/HCO3? interconversion in various tissues requires the presence of carbonic anhydrase (CA, EC 4.2.1.1). Fourteen CA isozymes are present in humans, all of them being used as biomarkers.

Area covered: A great number of patents and articles were focused on the use of CA isozymes as biomarkers for various diseases and syndromes in the recent years, in an ascending trend over the last decade. The review highlights the most important studies related with each isozyme and covers the most recent patent literature.

Expert opinion: The CAs biomarker research area expanded significantly in recent years, shifting from the predominant use of CA IX and CA XII in cancer diagnostic, staging, and prognosis towards a wider use of CA isozymes as disease biomarkers. CA isozymes are currently used either alone, in tandem with other CA isozymes and/or in combination with other proteins for the detection, staging, and prognosis of a huge repertoire of human dysfunctions and diseases, ranging from mild transformation of the normal tissues to extreme shifts in tissue organization and function. The techniques used for their detection/quantitation and the state-of-the-art in each clinical application are presented through relevant clinical examples and corresponding statistical data.  相似文献   

47.

Background

Nocturnal enuresis (NE) is a common symptom in children worldwide. International Children’s Continence Society (ICCS) defines enuresis as either mono-symptomatic, NE with lower urinary tract symptoms and NE with co-morbid conditions. The objectives of this study were to determine the frequencies and types of NE and associated symptoms and conditions in children aged 5 to 16?years based on ICCS criteria.

Methods

A multi-center cross sectional study was conducted between November 2012 and December 2013 in the primary care clinics of four hospitals in Karachi. Children aged five to fifteen years were included through consecutive sampling. Informed consent was obtained from the parents and a pre-coded semi-structured questionnaire was used to obtain the information. Data was entered on SPSS version 20.0 and multivariable logistic regression analysis was used for data analysis.

Results

Out of 429 children aged between five and sixteen years, 243(56.9%) were boys and the remaining 186(43.1%) were girls. One hundred and eighty three children (43%) had nocturnal enuresis (NE). Forty four (10.3%), had mono-symptomatic NE, 57(31.1%) had associated lower urinary tract symptoms (NE-LUTS), whereas 30 (16.3%) had NE with a co-morbid condition. Fifty two (28.4%) NE’s had at least one of both LUTS and a co-morbid condition. Out of the 246(57%) non-enuretic’s, 31(12.6%) had a LUTS, 95(38.6%) had a co-morbid condition and 57(23.2%) had at least one of both LUTS and a co-morbid condition. The remaining 63 (25.6%) were symptom free. Increased voiding frequency, urgency, dysuria, suprapubic pain and daytime incontinence were the LUTS significantly associated with NE. Co-morbid conditions significantly associated with NE included constipation, congenital defects, developmental delay, and learning and sleep problems.

Conclusion

Although NE can be an only symptom, it is often associated with lower urinary tract symptoms like dysuria, urgency, suprapubic pain, and daytime incontinence. Children presenting with NE often have co-morbid conditions like constipation, urinary tract infection, sleep disorders, and developmental delay. Many children presenting with these conditions as the primary complaint may also have NE. It should be addressed as unrecognized and untreated NE can cause additional morbidity and distress.
  相似文献   
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PurposeTo describe the pattern and types of ocular injuries in stone pelters in Kashmir valley during recent turmoil.DesignCross sectional study.MethodsSixty patients with different types of eye injuries were assessed between June–September 2010 and initial visual acuity was recorded. The injuries were classified according to Systems for Classifying Ocular Injuries (OTCS) and Ocular Trauma Score (OTS) was calculated in order to estimate the probability of follow-up visual acuity range.ResultsMost of the victims (75%) were young boys between 16–26 years with a mean age of 20.95, 95% of cases were males. The main cause of injury was stones (48.3%) and pellets (30%) besides rubber bullets, sling shots and tear gas shells.Most of the open-globe injuries due to stones were of Type B and A, Grade E, Zone II and III with Afferent Pupillary Defect (APD) in 30% of the cases. Closed-globe injuries were mostly of Type A, Grade C and D and Zone II and III.Most of the open-globe injuries due to pellets were of Type D, Grade D, Zone II and APD in 33.3%. Pellets Intra Ocular Foreign Body (IOFB) was in 41.6%. Most of the closed-globe injuries were of Type A, Grade D and E and of Zone III.Overall OTS of 1 was calculated in 16.6% and 3 in 53.3% of the cases.ConclusionIn stone pelting demonstrations eye injuries can result in visually significant trauma. Injuries due to pellets are mostly perforating and pellet IOFB, and both tend to have a very poor prognosis. OTS can be used to estimate visual prognosis.  相似文献   
50.
Introduction: About 20 patents have been published from 2013 to 2018 for developing advanced cancer therapeutics by targeting tubulin polymerization. Currently, there are several tubulin inhibitors that are in the drug development pipeline for various cancers alone or in combination including antibody-conjugated drugs (ACDs).

Areas covered: Important patents focusing on the development of tubulin inhibitors published from 2013 to 2018 are covered. This review mainly focuses on the tubulin inhibitors that are being synthesized and studied in cancer research along with their structures and their phases of development in preclinical and clinical research.

Expert opinion: Regulation of microtubules is important for cell division, cell motility, intracellular transport, and cell shape maintenance. Modulating its activity proved to be very effective in various diseases including different types of cancers. Microtubules are composed of two units, namely, alpha and beta-tubulin, and modifications at these ends affect both its functions and dynamics. A number of compounds that have been designed and synthesized bearing various heterocyclic scaffolds have been proven to modulate its activity and have emerged as potent tubulin inhibitors. This encourages more to study microtubules in order to find a variety of novel, potent compounds as anticancer drugs.  相似文献   
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