OILED SEDIMENTS IN THE HUMBER ESTUARY FOLLOWING THE SIVAND INCIDENT

1987 ◽  
Vol 1987 (1) ◽  
pp. 419-426 ◽  
Author(s):  
D. I. Little

ABSTRACT The Sivand oil spill of September 28, 1983, was unusual in that 6,000 t of crude oil were spilled in a highly turbid estuary. This study aimed to contribute to knowledge of spatial and temporal oil distribution and to examine its degradation. The role of suspended particulate matter (SPM) in the fate of oil is discussed, but the study concentrates on stranded oil in two sedimentologically distinct shorelines where ecological and conservation interests are high. The sites were Humberston Fitties, a sand flat, and Blacktoft Sand, a muddy shore in the inner estuary. Methods used were replicate sediment core sampling followed by gas liquid chromatography (GLC) and included ancillary sediment analyses. Soon after the spill, the sand total hydrocarbon (THC) concentration was greater than 50,000 ppm. Over 12 months this concentration decreased to about 3,000 ppm, as expected in coarser sediments. The muds were initially less contaminated (about 2,000 ppm), with only slight reductions in concentration over 12 months. However, there was strong evidence of sediment mobility at this site, and natural cleanup was in fact nearly complete after 9 months; the oil found at 12 months was due to transport of Sivand oil-contaminated muds from nearby reed beds. Good drainage at both sites permitted initial oil penetration. Root macropores at the muddy site encouraged penetration, weathering, and release of oil more easily than if it had been found in the sediment matrix. Sediment mobility at the muddy site contrasted with the firmness of the oiled sandflat, and contrary to vulnerability indices, may imply more rapid oil removal under some circumstances. Water washing was implicated as a major process in oil degradation at the sandy site, but no dramatic sediment turnover or erosion occurred that might have removed the oil. The steep gradients in oil concentration and composition with depth contrasted with the muddy site, where oil penetrated as a coherent mass via root macropores. The study illustrates the importance of sedimentological factors in the fate, effects, and mass balance of spilled oil. Published work on the Sivand has emphasized the effectiveness of cleanup and the lack of biological effects, but may have underestimated the amount of oil trapped in sediments.

Author(s):  
Rana A. Alaaeddine ◽  
Perihan A. Elzahhar ◽  
Ibrahim AlZaim ◽  
Wassim Abou-Kheir ◽  
Ahmed S.F. Belal ◽  
...  

: Emerging evidence supports an intertwining framework for the involvement of different inflammatory pathways in a common pathological background for a number of disorders. Of importance are pathways involving arachidonic acid metabolism by cyclooxygenase-2 (COX-2) and 15-lipoxygenase (15-LOX). Both enzyme activities and their products are implicated in a range of pathophysiological processes encompassing metabolic impairment leading to adipose inflammation and the subsequent vascular and neurological disorders, in addition to various pro-and anti-tumorigenic effects. A further layer of complexity is encountered by the disparate, and often reciprocal, modulatory effect COX-2 and 15-LOX activities and metabolites exert on each other or on other cellular targets, the most prominent of which is peroxisome proliferator-activated receptor gamma (PPARγ). Thus, effective therapeutic intervention with such multifaceted disorders requires the simultaneous modulation of more than one target. Here, we describe the role of COX-2, 15-LOX, and PPARγ in cancer and complications of metabolic disorders, highlight the value of designing multi-target directed ligands (MTDLs) modifying their activity, and summarize the available literature regarding the rationale and feasibility of design and synthesis of these ligands together with their known biological effects. We speculate on the potential impact of MTDLs in these disorders as well as emphasize the need for structured future effort to translate these early results facilitating the adoption of these, and similar, molecules in clinical research.


2018 ◽  
Vol 20 (2) ◽  
pp. 232-240 ◽  
Author(s):  
Izabella Mogilnicka ◽  
Marcin Ufnal

Background:Accumulating evidence suggests that microbiota play an important role in host’s homeostasis. Thus far, researchers have mostly focused on the role of bacterial microbiota. However, human gut is a habitat for several fungal species, which produce numerous metabolites. Furthermore, various types of food and beverages are rich in a wide spectrum of fungi and their metabolites.Methods:We searched PUBMED and Google Scholar databases to identify clinical and pre-clinical studies on fungal metabolites, composition of human mycobiota and fungal dysbiosis.Results:Fungal metabolites may serve as signaling molecules and exert significant biological effects including trophic, anti-inflammatory or antibacterial actions. Finally, research suggests an association between shifts in gut fungi composition and human health. Changes in mycobiota composition have been found in obesity, hepatitis and inflammatory bowel diseases.Conclusion:The influence of mycobiota and dietary fungi on homeostasis in mammals suggests a pharmacotherapeutic potential of modulating the mycobiota which may include treatment with probiotics and fecal transplantation. Furthermore, antibacterial action of fungi-derived molecules may be considered as a substitution for currently used antibacterial agents and preservatives in food industry.


2021 ◽  
Vol 14 ◽  
Author(s):  
Mohammad Najim Uddin ◽  
Mohammad Injamul Hoq ◽  
Israt Jahan ◽  
Shafayet Ahmed Siddiqui ◽  
Chayan Dhar Clinton ◽  
...  

: Thymoquinone (TQ) is one of the leading phytochemicals, which is abundantly found in Nigella sativa L. seeds. TQ exhibited various biological effects such as antioxidant, anti-inflammatory, antimicrobial, and anti-tumoral in several pre-clinical studies. Parkinson's disease (PD) is a long-term neurodegenerative disease with movement difficulties, and the common feature of neurodegeneration in PD patients is caused by dopaminergic neural damage in the substantia nigra pars compacta. The neuroprotective activity of TQ has been studied in various neurological disorders. TQ-mediated neuroprotection against PD yet to be reported in a single frame; therefore, this review is intended to narrate the potentiality of TQ in the therapy of PD. TQ has been shown to protect against neurotoxins via amelioration of neuroinflammation, oxidative stress, apoptosis, thereby protects neurodegeneration in PD models. TQ could be an emerging therapeutic intervention in PD management, but mechanistic studies have been remained to be investigated to clarify its neuroprotective role.


2021 ◽  
Vol 12 (4) ◽  
Author(s):  
Xiaoguang Gu ◽  
Jianan Zhang ◽  
Yajuan Ran ◽  
Hena Pan ◽  
JinHong Jia ◽  
...  

AbstractCircular RNAs have been reported to play significant roles in regulating pathophysiological processes while also guiding clinical diagnosis and treatment of hepatocellular carcinoma (HCC). However, only a few circRNAs have been identified thus far. Herein, we investigated the role of a specific closed-loop structure of hsa_circ_101555 that was generated by back-splicing of the host gene casein kinase 1 gamma 1 (CSNK1G1) in the development and proliferation of HCC. We investigated the expression of Hsa_circ_101555 in HCC and normal tissues using bioinformatics. The expression level of hsa_circ_101555 was further detected by fluorescence in situ hybridization and qRT-PCR in ten HCC patients. Transwell, migration, WST-1 assays, and colony formation assays were used to evaluate the role of hsa_circ_101555 in HCC development and proliferation. The regulatory mechanisms of hsa_circ_101555 in miR-145-5p and CDCA3 were determined by dual luciferase reporter assay. A mouse xenograft model was also used to determine the effect of hsa_circ_101555 on HCC growth in vivo. hsa_circ_101555 showed greater stability than the linear RNA; while in vitro and in vivo results demonstrated that hsa_circ_101555 silencing significantly suppressed cell proliferation, migration, and invasion of HCC cells. Rescue experiments further demonstrated that suppression of miR-145-5p significantly attenuated the biological effects of hsa_circ_101555 knockdown in HCC cells. We also identified a putative oncogene CDCA3 as a potential miR-145-5p target. Thus, our results demonstrated that hsa_circ_101555 might function as a competing endogenous RNA of miR-145-5p to upregulate CDCA3 expression in HCC. These findings suggest that hsa_circ_101555 may be a potential therapeutic target for patients with HCC.


Antioxidants ◽  
2019 ◽  
Vol 8 (8) ◽  
pp. 268 ◽  
Author(s):  
Izhar Hyder Qazi ◽  
Christiana Angel ◽  
Haoxuan Yang ◽  
Evangelos Zoidis ◽  
Bo Pan ◽  
...  

Selenium (Se) is an important trace mineral having many essential roles at the cellular and organismal levels in animal and human health. The biological effects of Se are mainly carried out by selenoproteins (encoded by 25 genes in humans and 24 in mice). As an essential component of selenoproteins, Se performs structural and enzymic roles; in the latter context it is well known for its catalytic and antioxidative functions. Studies involving different animal models have added great value to our understanding regarding the potential implications of Se and selenoproteins in mammalian fertility and reproduction. In this review, we highlight the implications of selenoproteins in male fertility and reproduction followed by the characteristic biological functions of Se and selenoproteins associated with overall male reproductive function. It is evident from observations of past studies (both animal and human) that Se is essentially required for spermatogenesis and male fertility, presumably because of its vital role in modulation of antioxidant defense mechanisms and other essential biological pathways and redox sensitive transcription factors. However, bearing in mind the evidences from mainstream literature, it is also advisable to perform more studies focusing on the elucidation of additional roles played by the peculiar and canonical selenoproteins i.e., glutathione peroxidase 4 (GPX4) and selenoprotein P (SELENOP) in the male reproductive functions. Nevertheless, search for the elucidation of additional putative mechanisms potentially modulated by other biologically relevant selenoproteins should also be included in the scope of future studies. However, as for the implication of Se in fertility and reproduction in men, though a few clinical trials explore the effects of Se supplementation on male fertility, due to inconsistencies in the recruitment of subjects and heterogeneity of designs, the comparison of such studies is still complicated and less clear. Therefore, further research focused on the roles of Se and selenoproteins is awaited for validating the evidences at hand and outlining any therapeutic schemes intended for improving male fertility. As such, new dimensions could be added to the subject of male fertility and Se supplementation.


1988 ◽  
Vol 22 (7-8) ◽  
pp. 582-587 ◽  
Author(s):  
Christine M. Quandt ◽  
Roger W. Sommi ◽  
Travis Pipkin ◽  
M.H. McCallum

Fifteen cases of presumed cocaine intoxication were evaluated in the emergency room (ER) at a city hospital over a four-day period. This series is unique in that many of these patients were from a similar area of the city, in some cases had the same street address, were regular abusers of cocaine, and presented to the ER with similar symptoms of tachycardia, dilated pupils, marked confusion, bizarre and sometimes violent behavior, psychosis, and hallucinations. Many of these symptoms were present several hours after drug use. Samples of a white powder presumed by the patients to be cocaine were obtained from two patients and analyzed by gas-liquid chromatography. Neither sample contained cocaine, but rather revealed atropine, benzocaine, and procaine. The signs and symptoms of cocaine, amphetamine, and atropine intoxication are reviewed and the problems of drug analysis and differential diagnosis of drug intoxication are discussed.


2006 ◽  
Vol 26 (22) ◽  
pp. 8515-8526 ◽  
Author(s):  
Judith Jans ◽  
George A. Garinis ◽  
Wouter Schul ◽  
Adri van Oudenaren ◽  
Michael Moorhouse ◽  
...  

ABSTRACT Cyclobutane pyrimidine dimers (CPDs) and 6-4 photoproducts (6-4PPs) comprise major UV-induced photolesions. If left unrepaired, these lesions can induce mutations and skin cancer, which is facilitated by UV-induced immunosuppression. Yet the contribution of lesion and cell type specificity to the harmful biological effects of UV exposure remains currently unclear. Using a series of photolyase-transgenic mice to ubiquitously remove either CPDs or 6-4PPs from all cells in the mouse skin or selectively from basal keratinocytes, we show that the majority of UV-induced acute effects to require the presence of CPDs in basal keratinocytes in the mouse skin. At the fundamental level of gene expression, CPDs induce the expression of genes associated with repair and recombinational processing of DNA damage, as well as apoptosis and a response to stress. At the organismal level, photolyase-mediated removal of CPDs, but not 6-4PPs, from the genome of only basal keratinocytes substantially diminishes the incidence of skin tumors; however, it does not affect the UVB-mediated immunosuppression. Taken together, these findings reveal a differential role of basal keratinocytes in these processes, providing novel insights into the skin's acute and chronic responses to UV in a lesion- and cell-type-specific manner.


2003 ◽  
Vol 1 (1) ◽  
pp. 25-32 ◽  
Author(s):  
G. Spoto ◽  
A. Contento ◽  
M. Di Nicola ◽  
G. Bianchi ◽  
C. Di Giulio ◽  
...  

Phosphodiesterase activity was tested on homogenized eyes of young and old rats kept in hypoxic and hyperoxic conditions, with the aim of correlating any difference in PDE activity with aging and variations in atmospheric oxygen contents. The activities of the two enzymes, cAMP phosphodiesterase (cAMP-PDE) and cGMP phosphodiesterase (cGMP-PDE), were tested. Phosphodiesterases seem to be particularly susceptible to variations in oxygen tension, suggesting an important role of cyclic nucleotides in cellular adaptive processes. Particularly, cAMP-PDE activity increases lightly both in hypoxic and hyperoxic conditions in young and old rats. For cGMP-PDE activity of young rats, a similar behaviour to cAMP-PDE activity is observed with a similar increase in hypoxic and hyperoxic conditions respect to the control rats. Instead old rats seem to be quite insensible to hypoxia, while they show a fair increase in cGMP-PDE activity in the case of hyperoxia. The second messengers cAMP and cGMP play important roles in mediating the biological effects of a wide variety of first messengers. The intracellular levels of cyclic nucleotides depend upon rates of synthesis and degradation, actuated, respectively, by cyclases and phosphodiesterases (PDEs). Therefore, PDEs seem to play an important role in a wide variety of physiological processes.


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