Characterization of Biochemical Pathways

Characterization of Biochemical Pathways Disscussion: Scorpion envenoming resulted in alteration in pyramidin, histidin, tyrosine, glycerophospholipid and steroid hormone biosynthesis pathways after 48 hours. These effects are an outcome of acute seizures and early myocardial injuries disorder in the group of experimental rates. Metabolite set enrichment analysis results also showed that pancreas, nerve cells and mitochondria are the most affected organs. The toxicity of a given compound refers to its ability to disrupt some biological functions at a certain level of biological organization (i.e., cell, tissue, or organ) It is also related to the amplitude and the duration of the exposure and also to the degree of absorption of the substance by the organism, its distribution, biotransformation and elimination or accumulation (Topol, 2004). Understanding the mechanism of a toxic event is a challenging task, especially in the field of drug research and development. The symptoms caused by scorpion stings in animal models are similar to those observed in humans (Padilla et al., 2005). Glycerophospholipids are known to display a high degree of molecular heterogeneity in mammalian tissues. In addition to their function as structural components of membranes, some molecular species may participate in specific biophysical and biochemical functions (Mason and Dobbs, 1980). Krshina Murthy (2000) suggested that the probable mechanism of death due to scorpion envenoming syndrome is alteration in phospholipid fractions concentrations mainly phosphatidylinositol and phospatidylglycerol (Murthy, 2000). He postulated that disruption of phosphatidylglycerol choline and phosphatidyl inositol are the main causes of death. Glycerophosphocholine metabolite are involved in cell signaling and membrane integrity of the cell and serine is the precursor for choline and acetylcholine biosynthesis which is required in the brain and therefore any damage of the cell membrane can affect glycerophospholipids metabolites pathway and its concentration. In our study, Glycerophospholipid metabolism was one of the main pathways that have been altered by envenomation and this confirms the Krishna Murthy hypothesis. Scorpion envenoming causes fuel-energy deficits and results in inability to utilize the existing metabolic substrates by different organs, which ultimately may lead to death. This is caused by a massive release of catecholamine, angiotensin II, an increase in glucagon and cortisol (Amaral et al., 1994; Avogaro et al., 1996; Balasubramaniam and Murthy, 1984; Basu et al., 1990; el-Amin, 1992; Gajalakshmi, 1982; Gueron and Ilia, 1996; Mirakabadi, 2013). Steroid hormones mediate a wide variety of vital physiological functions such as anti-inflammatory agents. They are also principally, involved in cell signaling, integrity and stability of the cell membrane as well as fuel or energy storage and energy source in cells. In our study cholesterol, dehydroepiandrosterone, 2-methoxyesterone and aldosterone profiles have shown changes. Disruption of cell membrane and liver function failure resulted due to cytotoxic effect of the H.lepturus venom (Heidarpour et al., 2012; R . Dehghani 2012). So the alterations in steroid hormones metabolites pathway are due to cytotoxic effects of venom. In the present investigation, envenomation by H. lepturus causes alteration in carnosine and 1-methylhistidine metabolite concentration of histidine metabolism pathway. Carnosine which is an endogenous cytoplasmic dipeptide(b-alanyl-l-histidine) and have numerous physiological activities in normal muscles activities (Nagasawa et al., 2001) Histidine and carnosine at low concentration could improve hyperglycemia complications with reduction of proinflammatory cytokine levels, increase insulin secretion, and enhance glutathione peroxidase activity. It has been showed that serum glucose elevated and hyperglycemia resulted by envenomation (Lee et al., 2005). Therefore, alteration in carnosine might be due to hyperglycemia state produced by scorpion venom. GENNIP (1999) showed that pyrimidine metabolism which is the building blocks of DNA and RNA is responsible for the cell programming machinery. Pyrimidine metabolism along with purine pathway fulfills a variety of functions in the metabolism of the cell of which the most important are regulation of energy conservation and transport, formation of coenzymes and of active intermediates of phospholipid and carbohydrate metabolism (GENNIP, 1999). Nyhan (2005) postulated that the catabolic pathways for pyrimidine have yielded a number of patients with specific enzymatic deficiencies, most of them with mental retardation, seizures, or both (Nyhan, 2005; Nyhan, 2005 ). Degradation disorders of pyrimidine can be presented as anemia, neurological deficits or devastating multisystem mitochondrial disorder (H. Anne Simmonds and Gennip, 2003). Our results also showed that the concentration of four metabolites of pyrimidine pathway i.e. Dihydrothymine, Deoxyuridine, Deoxycytidine, and Beta-alanine were changed which might be due to neurological deficits and acute seizures, which are caused by scorpion venom and change in cell metabolism. Venom of many scorpions species cause the activation and delay of inactivation of neural sodium channel which induce a massive release of catecholamines and acetylcholines by the postganglionic nerve both in the circulation and in specific organs, such as increase in rate and force of contraction of the heart tissues.(Gueron and Yaron, 1970; Sofer et al., 1997) Tyrosine is the main precursor for catecholamine, dopamine, epinephrine, and norepinephrine. Our results demonstrated that some of intermediate metabolites in this pathway including iodotyrosine, p-hydroxyphenylacetic acid and acetoacetic acid metabolite show changes which might be due to increase in catecholamine secretion in the stung victim. Similar clinical manifestations of diabetes are usually observed in scorpion sting victims(Zare and Tanikawa, 2002). Scorpion envenoming causes the release of counter-regulatory hormones (glucagon and cortisol) with suppressed insulin secretion. Under these conditions, the metabolism of carbohydrate, protein, and fat is directed towards catabolism. This provokes gluconeogenesis with glucose elevation in serum. During catabolic states such as starvation and diabetes free fatty acids and ketone bodies, compete as fuels for muscle metabolism. Whereas, after prolonged starvation in man free fatty acids displaced ketone bodies as preferred fuels for oxidation in striated muscle (Hagenfeldt et al., 1971; Owen and Reichard, 1971) intracellular ketone-body concentrations in striated muscle increased plasma concentrations rose during starvation and diabetic states and causes ketoacidosis and increase of H+ ions concentration of blood . In our study, synthesis and degradation of ketone bodies specially acetoacetic acid was affected in this pathway which is in accordance with Krishna Murthy study (Murthy, 2000). To summarize, our findings show that the application of metabolomics approaches could play an important role in the characterization of biochemical pathways in the animal model, which envenomed with Hemiscorpius lepturus venom. Our finding indicates the involvement of multiple system and organs in scorpion envenoming syndrome in which the most affected organs are pancreas, nerve cells, mitochondria, and spleen with similarities to acute seizures, the early marker of myocardial injuries and different seizures disorder, which confirm the earlier acute scorpion pancreatitis and myocardial injury reports (Bartholomew, 1970; Novikov et al., 2000).

Swiming with giants :: essays research papers

Swimming With Giants My Encounters with Whales, Dolphins, and Seals   Ã‚  Ã‚  Ã‚  Ã‚  The novel Swimming With Giants, by Anne Collet was an extraordinaire piece of literature about a biologists experience with the animals she loves. It is simply a book that expresses not only the wonder but also the tenderness that encounters with whales and other giants of the sea engender. The story tells of Anne Collet’s experiences as a young girl to a well known biologist.   Ã‚  Ã‚  Ã‚  Ã‚  When Anne Collet was a child she had her first encounter with the sea, as many young children do, by going on vacations with her family. From that point on she knew it was what she would want to do with her life. She went to college at a university in Brest and enrolled into the department of marine biology. This is where she began to study the sea and all its creatures in it. In 1973 Anne had her first Dolphin encounter and from then on became infatuated with the â€Å"Giants† of the sea. Her passion was for Dolphins and Whales. Collet became, and is today, the founder and director of the Center for Research on Marine Mammals in La Rochelle. She has been a Biologist for the past twenty years and has enjoyed every second of it. In her books she speaks with vivid intensity of her encounters with whales, dolphins and seals throughout the world’s oceans. She conveys the thrilling aspects of her work with marine mammals, from the sublime gaze of a whale’s eye to the race to save animals harmed by drift nets or toxic spills. Like the teenagers she regularly takes on her voyages, the reader will not only learn about such things as whale evolution and the unusual sensitivity of dolphins’ skin, but will experience her passion for the ocean, respect for its creatures, and heartfelt concern about â€Å"scorched sea† policy of over fishing, trawl fishing and pollution.

Climax, Symbolize and Theme in the Lottery Essay

â€Å"The Lottery† by Shirley Jackson is a very famous American short story. It was published in the June 26, 1948, issue of the The New Yorker. Written the same month it was published. It is ranked today as â€Å"one if the most famous short stories in the history of America literature.† It has been studied in preparatory schools and in universities since its publication. It is very controversial. Some like it, others do not. The lottery has climax, mood and theme.The lottery has a really crazy climax. Climax is the point of greatest emotional intensity in plot. I think the climax of story is killing the person who picks the lottery up. When they kill the woman, their eyes are changed to jealous. Someone said ‘Hurry up!’ and then they throw stones to the woman. Among the people, their family included. I was shocked about her family killed their mother. Even if the son’s face was very pitiful, his parents gave a stone and let him cast it. The chillin g climax also shows serious mood.The story also has extremely serious mood. The mood is generally defined as the atmosphere in the story. Although weather, surrounding and background in the story are sunny and clear, the electing process of the sacrificial victim is too quiet. The weather is a contrast to the village people. At least, the woman has only a tragic ending. She was killed by her friend and family. I think the best of the scene is children kill her too. It’s impossible, though custom is very important, they shouldn’t have let person sacrifice for their personal goal. These things made me confused to understand the story. The lottery has a theme which is difficult to understand. When I saw the title â€Å"The lottery†, I think this story has a good ending, but woman who won the lottery was killed by stones casted by people who she believes and love. It is very irony. Why they killed who won the lottery? I can’t understand this story exactly. But the author who wrote lottery gives us some message. There is old saying â€Å"Don’t judge a book by its cover† I think this crazy climax and serious mood make me difficult to understand this story.In conclusion, â€Å"The Lottery† is a short story which uses crazy climax, serious mood. I think Shirley Jackson who wrote â€Å"The Lottery† gives us some messages. First, don’t judge by appearance. This story title is â€Å"The Lottery†, but the ending is died who won the lottery. Second, we should remove wrong culture. Wrong culture killed innocent person. So, wrong culture is changed quickly. I searched a lot of information of this story. People say this story is written objectively. I strongly agree with this comment. They were extremely relieved when saw the women who won the lottery. In the movie of last scene, I felt selfishness from them.

Rock Provenance by Petrologic Methods

Sooner or later, almost every rock on Earth is broken down into sediment, and the sediment is then carried away somewhere else by gravity, water, wind or ice. We see this happening every day in the land around us, and the rock cycle labels that set of events and processes erosion. We should be able to look at a particular sediment and tell something about the rocks it came from. If you think of a rock as a document, sediment is that document shredded. Even if a document is shredded down to individual letters, for instance, we could study the letters and tell pretty easily what language it was written in. If there were some whole words preserved, we could make a good guess about the documents subject, its vocabulary, even its age. And if a sentence or two escaped shredding, we might even match it to the book or paper it came from. Provenance: Reasoning Upstream This kind of research on sediments is called provenance studies. In geology, provenance (rhymes with providence) means where the sediments came from and how they got where they are today. It means working backward, or upstream, from the grains of sediment we have (the shreds) to get an idea of the rock or rocks they used to be (the documents). Its a very geological way of thinking, and provenance studies have exploded in the last few decades. Provenance is a topic confined to sedimentary rocks: sandstone and conglomerate. There are ways of characterizing the protoliths of metamorphic rocks and the sources of igneous rocks like granite or basalt, but theyre vague in comparison. The first thing to know, as you reason your way upstream, is that transporting sediment changes it. The process of transport breaks rocks into ever smaller particles from boulder to clay size, by physical abrasion. And at the same time, most of the minerals in the sediment are chemically changed, leaving just a few resistant ones. Also, long transport in streams can sort out the minerals in sediment by their density, so that light minerals like quartz and feldspar can move ahead of heavy ones like magnetite and zircon. Second, once sediment arrives at a resting place—a sedimentary basin—and turns into sedimentary rock again, new minerals may form in it by diagenetic processes. Doing provenance studies, then, requires you to ignore some things and visualize other things that used to be present. Its not straightforward, but were getting better with experience and new tools. This article focuses on petrological techniques, based on simple observations of minerals under the microscope. This is the kind of thing geology students learn in their first lab courses. The other main avenue of provenance studies uses chemical techniques, and many studies combine both. Conglomerate Clast Provenance The big stones (phenoclasts) in conglomerates are like fossils, but instead of being specimens of ancient living things they are specimens of ancient landscapes. Just as the boulders in a riverbed represent the hills upstream and uphill, conglomerate clasts generally testify about the nearby countryside, no more than a few tens of kilometers away. Its no surprise that river gravels contain bits of the hills around them. But it can be interesting to find out that the rocks in a conglomerate are the only things left from hills that vanished millions of years ago. And this kind of fact can be especially meaningful in places where the landscape has been rearranged by faulting. When two widely separated outcrops of conglomerates have the same mix of clasts, thats strong evidence that they once were very close together. Simple Petrographic Provenance A popular approach for analyzing well-preserved sandstones pioneered around 1980 is to sort the different kinds of grains into three classes and plot them by their percentages on a triangular graph, a ternary diagram. One point of the triangle is for 100% quartz, the second is for 100% feldspar and the third is for 100% lithics: rock fragments that havent fully broken down into isolated minerals. (Anything that isnt one of these three, typically a small fraction, is ignored.) It turns out that rocks from certain tectonic settings make sediments—and sandstones—that plot in fairly consistent places on that QFL ternary diagram. For instance, rocks from the interior of continents are rich in quartz and have almost no lithics. Rocks from volcanic arcs have little quartz. And rocks derived from the recycled rocks of mountain ranges have little feldspar. When necessary, grains of quartz that are actually lithics—bits of quartzite or chert rather than bits of single quartz crystals—can be moved over to the lithics category. That classification uses a QmFLt diagram (monocrystalline quartz–feldspar–total lithics). These work pretty well in telling what kind of plate-tectonic country yielded the sand in a given sandstone. Heavy Mineral Provenance Besides their three main ingredients (quartz, feldspar, and lithics) sandstones have a few minor ingredients, or accessory minerals, derived from their source rocks. Except for the mica mineral muscovite, they are relatively dense, so theyre usually called heavy minerals. Their density makes them easy to separate from the rest of a sandstone. These can be informative. For instance, a large area of igneous rocks is apt to yield grains of hard primary minerals like augite, ilmenite or chromite. Metamorphic terranes add things like garnet, rutile, and staurolite. Other heavy minerals like magnetite, titanite, and tourmaline could come from either. Zircon is exceptional among the heavy minerals. It is so tough and inert that it can endure for billions of years, being recycled over and over like the coins in your pocket. The great persistence of these detrital zircons has led to a very active field of provenance research that starts with separating hundreds of microscopic zircon grains, then determining the age of each one using isotopic methods. The individual ages arent as important as the blend of ages. Every large body of rock has its own blend of zircon ages, and the blend can be recognized in the sediments that erode from it. Detrital-zircon provenance studies are powerful, and so popular nowadays that theyre often abbreviated as DZ. But they rely on expensive labs and equipment and preparation, so theyre mainly used for high-payoff research. The older ways of sifting, sorting and counting mineral grains are still useful.