User:IiKkEe

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It has been suggested that a place a notice here that I have been editing for the first time for the past two weeks, and not using the "minor edit" box correctly. It was not my intent to hide my major edits: I just assumed the wrong meaning of the term. I have also been told there is no way to change this after the fact. I believe what are actually major edits are obvious from the comment box entry. These are accurate.

IiKkEe (talk) 21:28, 25 April 2014 (UTC)


https://en.wikipedia.org/wiki/Wikipedia:Contact_us https://en.wikipedia.org/wiki/Wikipedia:EMPHASIS#Emphasis https://en.wikipedia.org/wiki/WP:Requesting_copyright_permission https://en.wikipedia.org/wiki/WP:Referencing_for_beginners https://en.wikipedia.org/wiki/MOS:DASH

Thermogenesis references

PMC3673773 - Adaptive thermogenesis 100,000 kCal stored in a 70 kg person "Cordinated regulation o energy intake and expenditure mediated by signals emanatin from adipose, gastrointestinal, and endocrine rissues, and integrated by the liver and CNS" lose weight 10% - daily energy enditre goes down 25% -lose 10% wt - gain 20% icrease in skeletal muscle chemomechanicl efficiency,18% gain in FFA use as fuel during light exsrcise PMID12609816 -UCP in BAT yilds more heat generation -BAT activation: ,beta-3 R,THR (thyroid hormone receptor) 19912477 -Leptin sensitive decline in SNS, thyrioid with weight loss COULD BE mechanism of reduced thermog. by BAT -only takes 25G of BAT to explain decline in REE -All of above applies to rodents, noy humans: little BAT im humans: YES THERE IS: BAT in 7.5% womwn, 10% men using PET scans. - Expose to cold: 23/24 have BAT on PET(19357405) - leptin prop to fat mass (8784109corti) -letin conc inv prop to hunger ratings(9822946) -give leptin, hyperphagia goes away (10486419) -Leptin goes down, intake goes up, due to more POMC, less Y(NPY) (AgRP) and (MCH)anorexogenic neuropeptitide POMC; orixigens neuropeptideY, agouti-related peptide, melanin concentrating hormone -leptin gors down,POMC goes down -low leptin meanslow HPT, high HPA -POMC proopiomelaocortin This is it: administration of leptin tolow leptinhumans causes energy expenditure up,energy intake down, SNS up, normalizes HPA, thyroid gonadalfn(11297566)(10486419) -BUT if NoT leptin def,to get a wt loss effect requires dose of L to get L conc overten times normal(10546697) -SUMMARY: lose wt, allsystems attempt to restore wt: metabolic, neuroendocrine,autonomic behavoioiural changes all oppose. FAT STORES ARE DEFENDED BY INTERLOCKINGBIOENERGETCAND NEUROBIOLOGICALPHSIOLOGIES. THe HUMAN BODY ACTIVELY OPPOSES THE CURE. - acponline.org -1999review of1320 papers , No PMID! Perfect diagrams OUTLINE GENETICS REGULATION OF SERUM LEPTIN LEVELS leptin ACTION AND CLEARANCE tHE ROLE OF LEPTIN IN HUMAN PHYSIOLOGY AND PATHOPHYSIOOGY NEONATE cHILHOOD AND PUBERTY← lEPTIN AND LEPTIN RESISTANCE IN HUMAN OBESITY lEPTIN AND THE METABOLIC AND NEUROENDOCRINE RESONSE TO FOOF DEPRIVATION l in hYPERTENSION,←DIABETES,×POLYCYSTIC OVARIAN DISEASE l IN EATING DIRORDERS L IN OTHER CLINICALSRTATES cLINICAL TRIALS FUTURE DIRECTIONS

fROM "The Role of leptin in human Mantzoros obesity and disease 199 Annala vol130 #8

IiKkEe (talk) 01:19, 30 April 2014 (UTC)

MCR - melanocortin


references

− − Imagawa, et al. Structure-Function Studies of Human Leptin. JBC. 1998, December; 52(273): 35245-35249 y

− Cterminal necessary for secretion, stability, solubility.

− − mammary epithelial cells, bone marrow, pituitary sites of leptin

− − Kline, et al. Leptin is a four-helix bundle: secondary structure by NMR. FEBS Letters.1997, February; 407(2): 239-242 - exhibits a short strand segment and two long random coil loops. Determined secondary structure by NMR. Long chain short helix cytokine fold.

− − Peelman, et al. Mapping of the leptin binding sites and design of a leptin antagonist. JBC. 2004, September; 39(279): 41038-41046 - synthesized first leptin antagonist, caused obesity, altered immune system, hypogonadism. Binding site is the N terminal 94 AA

− − Zhang, F., et al. Crystal Structure of the obese protein leptin-E100. Nature. 1997, May; 387(6629):206-209. First to crystallize. Leptin aggregates so cannot be crystallized

− . Disulfide bonding critical. structure unique

− − Cannot crystallize AA 27-38 As od 2008, don't fully know structure, Rigid hydrophobic core: unique. Core has a hydrophobic cap which buries the lipophilic residues on the the surface of the BD helical bundle

− Pathophysiology

The major mechanism of lead toxicity is due to increased generation of reactive oxygen species (ROS) and interference with generation of antioxidants. Lead causes the generation of ROS like hydroperoxide, hydrogen peroxide, and singlet oxygen. ROS are stabilized by glutathione in the body. Ninety percent of glutathione in the cell exists in reduced form and 10% in oxidative form, and it typically acts as an antioxidant defense mechanism. Glutathione stabilizes ROS, and after being converted (oxidizing) to glutathione disulfide, it is reduced back to GSH by glutathione reductase. Lead inactivates glutathione by binding to GSH’s sulfhydryl group, which causes GSH replenishment to become inefficient, thereby increasing oxidative stress. Lead also interferes with the activity of other antioxidant enzymes including superoxide dismutase and catalase. The increase in oxidative stress leads to cell membrane damage due to lipid peroxidation. Lead blocks the activity of 5-aminolevulinic acid dehydratase and leads to hemoglobin oxidation, which along with the lipid peroxidation can result in red cell hemolysis. [9]

Lead entering the intravascular space binds quickly to red blood cells. Lead has a half-life of approximately 30 days in the blood, from where it diffuses into the soft tissues, including the kidneys, brain, liver, and bone marrow.

Lead then diffuses into bone and is stored there for a period that corresponds to a half-life of several decades. Increased bone turnover with pregnancy, menopause, lactation, or immobilization can increase blood lead levels. Estimations of blood lead levels are more useful for diagnosing acute lead poisoning, whereas the extent of past lead exposure can

TRANSITION METALS

Post-transition metals in the periodic table
  Elements classified as post-transition metals by Masterton, Hurley and Neth:[1] Ga, In, Tl, Sn, Pb, Bi
  Also recognised by Huheey, Keiter and Keiter:[2] Al, Ge, Sb, Po; and by Cox:[3] Zn, Cd, Hg
  Also recognised by Deming:[4] Cu, Ag, Au (but he counted Al and groups 1 and 2 as 'light metals')[n 1]
  Elements that might be post-transition metals: At, Cn, Nh, Fl, Mc, Lv, Ts

Post-transition metals are a group of metallic elements in the periodic table located between the transition metals to their left, and the metalloids to their right. Depending on where these adjacent groups are judged to begin and end, there are at least five competing proposals for which elements to include, ranging from six to fourteen elements. All proposals include gallium, indium, tin, thallium, lead, and bismuth.

Physically, post-transition metals are soft (or brittle), have poor mechanical strength, and have melting points lower than those of the transition metals. Being close to the metal-nonmetal border, their crystalline structures tend to show covalent or directional bonding effects, having generally greater complexity or fewer nearest neighbours than other metallic elements.

Chemically, they are characterised—to varying degrees—by covalent bonding tendencies, acid-base amphoterism and the formation of anionic species such as aluminates, stannates, and bismuthates (in the case of aluminium, tin, and bismuth, respectively). They can also form Zintl phases (half-metallic compounds formed between highly electropositive metals and moderately electronegative metals or metalloids).

There is no officially sanctioned name for this term, such as by the IUPAC. The origin of the term is unclear: one early use was in 1940 in a chemistry text.[8] Alternate names for this group are B-subgroup metals, other metals, and p-block metals; and by at least eleven other labels.

Names for sets of chemical elements From Wikipedia, the free encyclopedia

There are currently 118 known chemical elements exhibiting a large number of different physical and chemical properties. Amongst this diversity, scientists have found it useful to use names for various sets of elements, that illustrate similar properties, or their trends of properties. Many of these sets are formally recognized by the standards body IUPAC.[1]

The following names are approved by IUPAC:

   Alkali metals – The metals of group 1: Li, Na, K, Rb, Cs, Fr.
   Alkaline earth metals – The metals of group 2: Be, Mg, Ca, Sr, Ba, Ra.
   Pnictogens – The elements of group 15: N, P, As, Sb, Bi. (Mc had not yet been named when the 2005 IUPAC Red Book was published, and its chemical properties are not yet experimentally known.)
   Chalcogens – The elements of group 16: O, S, Se, Te, Po. (Lv had not yet been named when the 2005 IUPAC Red Book was published, and its chemical properties are not yet experimentally known.)
   Halogens – The elements of group 17: F, Cl, Br, I, At. (Ts had not yet been named when the 2005 IUPAC Red Book was published, and its chemical properties are not yet experimentally known.)
   Noble gases – The elements of group 18: He, Ne, Ar, Kr, Xe, Rn. (Og had not yet been named when the 2005 IUPAC Red Book was published, and its chemical properties are not yet experimentally known.)
   Lanthanoids – Elements 57–71: La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu.
   Actinoids – Elements 89–103: Ac, Th, Pa, U, Np, Pu, Am, Cm, Bk, Cf, Es, Fm, Md, No, Lr.
   Rare-earth elements – Sc, Y, plus the lanthanoids.
   Transition metals – Elements in groups 3 to 11 or 12.

Another common classification is by degree of metallic – metalloidal – nonmetallic behaviour and characteristics. There is no general agreement on the name to use for these sets: in this English Wikipedia, the name used is category without any claim to universality. Very often these categories are marked by a background color in the periodic table. Category names used are:

   Alkali metals, alkaline earth metals, noble gases, and transition metals: Same as the IUPAC system above.
   Lanthanoids and actinoids are instead referred to as lanthanides and actinides respectively.
   Rare-earth elements, pnictogens, chalcogens, and halogens are not used as category names, but the latter three are valid as group (column) names.
   Additional element category names used:
       Post-transition metals – The metals of groups 13–17: Al, Ga, In, Tl, Sn, Pb, Bi, Po. Nh, Fl, Mc, Lv, and Ts are additionally predicted to be post-transition metals. The metals of group 12 are often also included.
       Metalloids – Elements with properties intermediate between metals and non-metals: B, Si, Ge, As, Sb, Te, At.
       Polyatomic nonmetals – Nonmetals distinguished by polyatomic bonding in their standard states, in either discrete or extended molecular forms: C, P, S and Se.
       Diatomic nonmetals – Nonmetals that exist as diatomic molecules in their standard states: H, N, O, F, Cl, Br, I.
       Superactinides – Hypothetical series of elements 121 to 157, which includes a predicted "g-block" of the periodic table.

Many other names for sets of elements are in common use, and yet others have been used throughout history. Usually those sets do not aim to cover the whole periodic table (as for example period does). Some examples:

   Precious metal – Variously-defined group of non-radioactive metals of high economical value.
   Coinage metals – Various metals used to mint coins, primarily the group 11 elements Cu, Ag, and Au.
   Platinum group – Ru, Rh, Pd, Os, Ir, Pt.
   Noble metal – Variously-defined group of metals that are generally resistant to corrosion. Usually includes Ag, Au, and the platinum-group metals.
   Heavy metals – Variously-defined group of metals, on the base of their density, atomic number, or toxicity.
   Native metals – Metals that occur pure in nature, including the noble metals and others such as Sn and Pb.
   Earth metal – Old historic term, usually referred to the metals of groups 3 and 13, although sometimes others such as beryllium and chromium are included as well.
   Transuranium elements – Elements with atomic number greater than 92.
   Transactinide elements – Elements after the actinides (atomic number greater than 103).
   Transplutonium elements – Elements with atomic number greater than 94.
   Minor actinides – Actinides found in significant quantities in nuclear fuel, other than U and Pu: Np, Am, Cm.
   Heavy atom – term used in computational chemistry to refer to any element other than hydrogen and helium.

Status of Lead 30 Aug 2017

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