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alpha glucoside for control of type 2 diabetes alveolar Po2 - PAo2; the partial pressure of carbon dioxide gas in the alveolar sacs alveolar ventilation - effective air exchange between alveoli and blood alveoli - air sacs at the end of air ducts in the lungs and in contact with capillaries that allow gases to diffuse in or out (singular: alveolus) Alzheimer's disease - progressive brain disorder with deterioration of mental capacity affecting memory and judgment amniotic fluid - liquid that surrounds the fetus in the amniotic cavity amperometry - measuring current in amperes, including coulometric methods amyloidosis - metabolic disorder with starch accumulation in organs and tissues anabolism - the constructive phase of metabolism analgesics - medications that relieve pain anaplasia - loss of cell differentiation and change in structure anencephaly - a fatal congenital absence of or greatly reduced brain, particularly the cerebrum, resulting from failure of the neural tube to close during organ formation angina - chest pain due to inadequate supply of oxygen to heart muscle anion - an ion carrying a negative charge anion gap - the unmeasured anions in plasma present with bicarbonate and chloride to balance sodium and potassium cations

540 GLOSSARY

anisocytosis - variation in sizes of red blood cells:

smaller, larger, or both anode - a positively charged electrode that attracts anions (negative ions) anorexia - loss of appetite antecubital fossa - area in the crook of the arm anthropometric - literally means the "measure of man"; type of measurement also referred to as body composition analysis antibody - an immunoglobulin produced by a B lymphocyte in response to a unique antigen antibody titer - measure of the amount of antibody against a particular antigen present in the blood antigen - a protein or oligosaccharide that elicits an antibody response antipyretics - medications that reduce fever antistreptolysin-O (ASO) titer - measurement of antibodies to a protein component of group A Streptococcus bacteria apoferritin - the protein portion of ferritin, the storage form of iron apoprotein - the protein portion of a lipoprotein ARDS - respiratory distress syndrome of the adult;

acquired respiratory failure ascariasis - infection with the parasite Ascaris lumbri-coides ascites - accumulation of serous fluid in the abdomen atelectasis - partial or complete lung collapse due to obstruction of the airway atherosclerosis - fatty accumulation causing hardening and plugging in blood vessels atrophy - decrease in size or function automation - ability of an instrument to perform a laboratory test with minimal human involvement azotemia - an elevated level of urea in the blood basal metabolic rate - baseline rate of metabolism based on gender and weight (in kcal/24 hr) base excess - concentration of titratable base in a solution with pH 7.40 and Pco2 of 40 mm Hg batch analysis - a group of samples are analyzed at the same time for the same test Bence Jones protein - free light chains of the immunoglobulin molecule benign - cell growth that doesn't spread and is cured with removal benzoic acid analog - a compound that is structurally similar to C7H6O2 and used for control of type 2 diabetes beriberi - disease characterized by peripheral neurological, cerebral, and cardiovascular abnormalities; caused by deficiency of thiamine biclonal - arising from two cell lines biliary canaliculi - small ducts or tubes that carry bile out from the liver leading to the small intestine biochemical marker - any biochemical compound, such as an antigen, antibody, abnormal enzyme, or hormone, that is sufficiently altered in a disease to serve as an aid in diagnosing or in predicting susceptibility to the disease blastocyst - spherical shell enclosing fluid-filled cavity with the inner cell mass that will become the embryo at one pole and an outer layer of cells that will form the embryonic placenta blood urea nitrogen (BUN) - urea concentration in the blood; historically, urea was measured as nitrogen remaining from a protein-free filtrate of the blood blood-borne - carried or transmitted by blood buffalo hump - fat accumulation on upper shoulders and collar bone causing the neck and head to jut forward buffer - a mixture of chemicals that resist changes in pH by combining with free H+ (proton acceptor) and OH-, generally a strong salt and weak acid or base; human buffer systems include anionic proteins, deoxyhemoglobin, phosphate buffers, and bicarbonate/carbonic acid buffers calculi - any abnormal concretion of precipitated inorganic materials, commonly called a stone, within the body (singular: calculus) canalicular - within canals or small ducts carbonic anhydrase inhibitors - compounds that reduce the secretion of H+ ions through alkaliniza-tion of the urine; drugs that are commonly used to treat glaucoma carboxypeptidase - a pancreatic enzyme that hydro-

lyzes peptides from the C-terminal end cardiac catheterization - insertion of thin, flexible tube into the heart and coronary arteries for detecting blood pressure and flow and taking images carryover - a sampling problem that occurs when remnants of a previous sample or test reaction product affect later samples catabolism - the destructive phase of metabolism catalyze - to accelerate the rate of a chemical reaction without being consumed catecholamine metabolites - products of cate-cholamine metabolism (e.g., vanillylmandelic acid, homovanillic acid, metanephrine, normetanephrine) catecholamines - biogenic amines that contain an aromatic catechol and an aliphatic amine (e.g., epi-nephrine, norepinephrine, dopamine)

cathode - a negatively charged electrode that attracts cations (positive ions) cation - an ion carrying a positive charge celiac sprue - malabsorption syndrome resulting from intolerance to dietary wheat proteins centrifugal analysis - using centrifugal force to achieve chemical reaction and analysis cerebrovascular accident - stroke or sudden loss of blood flow to the brain due to obstruction or clot in the blood vessels certification - the process by which a nongovernmental agency or association grants recognition to an individual who has met certain predetermined qualifications specified by that agency or association chain of custody - additional documentation of the condition of a specimen, all procedures performed, and personnel who have encountered a test specimen chemiluminescence - light emitted by a chemical reaction chief cells - secretory cells that line the gastric glands and secrete pepsin or its precursor, pepsinogen cholecystokinin - hormone secreted by the upper small intestine that stimulates contraction of the gallbladder and pancreatic secretion cholestasis - obstruction of the flow of bile; standing bile choroid plexus - cavities in the cerebrum lined with thin membranes and blood vessels chromatogram - record of molecular separation taking place in chromatography chromatography - a technique for separating similar molecules based on differential absorption and elu-tion chromogen - colored product formed in a colorimet-ric reaction chronic bronchitis - long-standing irritation and inflammation of the respiratory ducts chylomicron - parcel of lipids and proteins made from dietary fats (especially triglycerides) during intestinal absorption chymotrypsin - digestive enzyme produced by the pancreas that, with trypsin, hydrolyzes proteins to peptones or amino acids clearance - the elimination of a substance, as related to its removal from the blood plasma by the kidneys

Clinical Laboratory Improvement Amendments of 1988 (CLIA) - quality standards for all clinical laboratories to ensure the accuracy, reliability, and timeliness of patient test results regardless of where the test was performed; the Centers for Medicare and Medicaid Services regulates all laboratory testing (except research) performed on humans in the United States clones - genetically identical cells closed reagent system - analytical system for which the reagents, in a unique container or format, are provided only by the manufacturer cluster of differentiation (CD) - cell membrane molecules used to classify leukocyte subsets colonoscopy - examination of the upper portion of the rectum with an instrument colorimetric - determining analyte from visible light absorption of a colored product competitive immunoassay - immunoassay in which patient antigen and labeled reagent antigen compete for the same binding site on the antibody conductivity - the combined ability of ions to carry a charge confirmatory test - using laboratory tests to verify that an initial test result is accurate; should be very specific continuous flow analysis - each sample passes through the same stream and reactions as all other samples, with only a brief washout phase between samples coproporphyrin - water-soluble tetrapyrrole precursor of heme found in urine and feces cor pulmonale - right-sided heart failure coronary arteries - three major blood vessels supplying blood and oxygen to the heart muscles corpus luteum - yellow glandular mass that develops from an ovarian follicle following the release of a mature oocyte and secretes progesterone coulometry - measuring aspects of current, including rate of electron flow; often used in titration of ions coupled - chemical reactions that share a common intermediate credentialing - the processes involved in identifying those institutions and individuals meeting acceptable standards in areas of accreditation, certification, or licensure cretinism - growth deficiency and mental retardation Crohn's disease - inflammatory disease of the gastrointestinal tract that can lead to intestinal obstruction cryoglobulinemia - presence in the blood of an abnormal protein that forms gels at low temperatures current - electrical charge (in coulombs/second); measured in units of amperes

542 GLOSSARY

cyanotic - characterized by bluish appearance due to lack of tissue oxygenation cyclopentanoperhydrophenanthrene - an organic molecule with 17 carbon atoms composed of three six-sided rings (the phenanthrene portion) and one five-sided ring deemed status - permission given to an external second party to act as the agent of the first party definitive test - highly sensitive and specific test in which results can be used as legal evidence dehydroepiandrosterone - 19-carbon molecule found in small amounts as a precursor to some estrogens in women and as a precursor to male sex steroids in men delta check - comparison of concentration an analyte to values from previous specimens in the same patient; a form of quality assurance densitometry - using colorimetry to determine the quantity of a dense region, such as in protein elec-trophoresis densitometry dermatitis - an inflammatory rash desensitization - lowering of responsiveness detoxification - removal of waste or toxins from a fluid, rendering it harmless dexamethasone - a synthetic glucocorticoid used to determine the cause of hypercortisolism diabetes insipidus - lack of antidiuretic hormone output or response causing polyuria and potential dehydration diabetic nephropathy - disease of the kidney, including inflammatory, degenerative, and sclerotic conditions, caused by diabetes diagnostic sensitivity - the likelihood that, given the presence of disease, an abnormal test result predicts the disease diagnostic specificity - the likelihood that, given the absence of disease, a normal test result excludes disease diffuse - present over a large area digital rectal examination - palpation of the prostate gland with a gloved finger inserted into the rectum disaccharidases - enzymes that hydrolyze the glycolic bond of disaccharides disaccharides - simple carbohydrates composed of two monosaccharides discrete analysis - test reactions occur in separate compartments diuretic - agent that promotes urine formation diurnal variations - changes in chemical levels during the day, especially when comparing two different times

DNA - deoxyribonucleic acid; in the eukaryote and some prokaryotes, the chemical that transmits inherited characteristics of an organism to its progeny downregulation - inhibition or suppression of the normal response of an organ or system duodenum - the first part of the small intestine that is adjacent to the pyloric region of the stomach eclampsia - coma and convulsive seizures of the mother between week 20 of pregnancy and the end of the first week after birth ectoderm - the outermost of the three primary germ layers of an embryo forming neural tissue ectopic - occurring outside the expected location ectopic hormone secretion - production of hormones by nonendocrine cells edematous - puffed up due to visible accumulation of fluids

Edwards' syndrome - congenital and fatal defect of the fetus (trisomy 18) causing severe multiorgan defects, including mental deficiency ejaculation - ejection of sperm cells and seminal fluid at orgasm elastase - an enzyme that dissolves elastin electrocardiogram (ECG) - tracing of electrical activity of the heart electrochemistry - measuring potential, current, or resistance to determine the activity of an analyte electrode - a terminal that detects changes in current or voltage in response to changes in the environment electrolytes - substances that ionize in solution and conduct electricity electrophoresis - a separation technique of different charged molecules in solution in an electrical field of varying potential electrostatic - producing electrical attractions within or between groups of molecules eluate - the liquid obtained from a column during separation; derived from washing elute - remove based on solubility embryo - rapidly growing and developing human organism before the 10th week of gestation emission - giving off or sending out emphysema - chronic pulmonary disease marked by abnormal increase in the airspaces and destructive changes in their walls encephalocele - congenital opening in the skull with protrusion of brain tissue endogenous - originating inside the body endometrium - lining of the uterus endoplasmic reticulum - cell organelle that serves as a compartment for numerous chemical reactions energy malnutrition - nutritional deficiency caused by inadequate intake of calories, protein, or both, seen in children under age 5 years or persons undergoing stress of major illness; also protein-calorie malnutrion epilepsy - a recurrent disorder of cerebral function characterized by a variety of attacks caused by excessive discharge of cerebral neurons epitopes - specific antibody binding sites found on an antigen erythropoietic - pertaining to blood cell production esophageal varices - tortuous dilatation of veins of the esophagus essential nutrients - molecules that are required for metabolism but cannot be produced by the body; required in the diet ester - compound formed by combination of an organic acid and an alcohol with elimination of water estradiol - 18-carbon steroid molecule that is the main estrogen found in nonpregnant women estriol - 18-carbon steroid molecule that is the main estrogen found in pregnant women estrone - 18-carbon steroid molecule that is less active than other estrogens ethanol - ethyl alcohol, CH3CH2OH etiology - the cause of disease euthyroid - showing normal clinical signs and normal thyroid function status despite the indications of dysfunction in some thyroid test results ex vivo - outside of a living being excretion - the elimination of waste products from the body exocrine glands - glands that secrete externally through ducts exogenous - originating outside an organ or part of the body exophthalmos - protrusion of eyeballs due to accumulation of fluid and metabolic products false negative - result below the decision limit in a patient who has the disease false positive - result at or above the decision limit in a patient who does not have the disease ferritin - the storage form of iron found in the liver, spleen, and bone marrow fertilization - union of two gametes: male (sperm cell)

and female (oocyte) fetus - unborn but recognizable human organism between 10 weeks' and 40 weeks' gestation filtration - the process of removing particles from a solution by passing the solution through a membrane or other barrier Fio2 - amount of oxygen available to breath first-order (metabolic) kinetics - reaction in which velocity of metabolism by enzymes is proportional to the concentration of substrate (drug) flatulence - excessive gas in the stomach and intestines fluorescence - emission of low-energy light quickly after absorbing high-energy light; a type of luminescence fluorometer - instrument that detects fluorescent emissions focal - present in one small area follicle - sac produced by the ovary containing an oocyte follicular phase - first half of the female menstrual cycle leading up to maturity of one follicle and release of an oocyte forensic testing - testing in which results can be submitted to help answer a question of law or as evidence in a legal decision galactosemia - an inherited disorder marked by the inability to metabolize galactose due to a congenital absence of the enzyme galactose-1-phosphate uridyl transferase gametocyte - sperm cell or oocyte gammopathy - any disease in which serum immunoglobulins are increased gastrectomy - surgical removal of part or all of the stomach gastrinoma - gastrin-secreting tumor gastritis - inflammation of the gastric mucosa genome - the complete set of genetic information produced by the cell glucocorticoids - adrenal cortical hormones primarily active in protecting against stress and affecting protein and carbohydrate metabolism gluconeogenesis - formation of glucose from excess amino acids, fats, or other noncarbohydrate sources glycemic - pertaining to control of blood glucose levels glycogenesis - formation of glycogen glycogenolysis - glycogen stored in the liver and muscles is converted to glucose 1-phosphate and then to glucose 6-phosphate goiter - enlarged, usually hyperactive thyroid gland due to a variety of causes gold standard method - test method that provides the best available approximation of a true value

544 GLOSSARY

gonads - reproductive organs: the testes in the male and ovaries in the female gravimetric - measuring mass to relate to density or other concentration half-life - one-half of the time between synthesis and degradation of a compound/time needed for the concentration of a drug to decrease by half hapten - low molecular weight chemical coupled to a carrier protein to become a suitable immunogen hematopoiesis - the production and development of blood cells hemoconcentration - relative increase in the number of red blood cells resulting from a decrease in the volume of plasma hemoglobinopathies - diseases that result in structural abnormalities of globin chains hemolysis - rupture of erythrocyte cell membrane causing release of intracellular contents hemosiderin - granular iron oxide found in the bone marrow or other cells Henderson-Hasselbalch equation - equation that relates pH of blood plasma to equilibrium of salt (HCO3-) and weak acid (H2CO3) hepatic - pertaining to the liver hepatobiliary - relating to bile ducts and ducts within the liver heterogeneous assay - immunoassay in which bound and free antibody must be separated before label is measured homeostasis - the state of dynamic equilibrium of the internal environment of the body that is maintained by processes of feedback and regulation in response to external or internal changes homogeneous assay - immunoassay in which bound and free antibody need not be separated before label is measured human chorionic gonadotropin (hCG) - classic hormone marker of pregnancy produced by the placenta after the fertilized ooctye implants human placental lactogen (hPL) - hormone produced by the placenta and involved in maternal glucose and fat metabolism and mammary gland function hybridoma - a fused lymphocyte and myeloma cell used for making specific antibodies hydrophobic - water insoluble hydrops fetalis - stasis of fluids in tissue spaces, secondary to loss of albumin, leading to a condition in infants of hepatosplenomegaly and respiratory and circulatory distress hyperkalemia - increased potassium in blood plasma hypernatremia - increased sodium in blood plasma hypernatriuric - exhibiting increased urinary sodium hyperplasia - increase in cell mass, often with increased function hypertension - in adults, blood pressure higher than 140 mm Hg systolic or 90 mm Hg diastolic on three separate readings recorded several weeks apart hyperthermia - heat intolerance and higher than normal body temperature hypertonicity - increased concentration of a body fluid due to increased solute compared to water in solution hyperviscosity - gelatinous nature or excessive viscosity hypochromic - having a large pale central area due to less hemoglobin (red blood cells) hyponatremia - decreased sodium in blood plasma hypo-osmolality - decreased concentration (tonicity) of a body fluid due to decreased solute compared to water in the solution hypoperfusion - decreased passage of blood through vessels of an organ hypophysectomy - resection or removal of the pituitary hypophysis - pituitary or master endocrine gland hypovolemia - decreased blood volume; may be caused by fluid losses or inadequate fluid intake hypoxia - decreased oxygen supply to tissue despite adequate perfusion of the tissue icterus - yellowish pigmentation in the blood due to increased bilirubin idiopathic - without a recognizable cause immunoassay - test tha measures the protein or protein-bound molecules concerned with the reaction of an antigen with its specific antibody immunochemical - chemical that is able to enter into an antibody-antigen reaction immunogen - high molecular weight molecule that stimulates antibody production; antigen in utero - within the uterus in vitro - pertaining to laboratory conditions, such as specimens in a test tube inborn error of metabolism - an inherited metabolic disease that often causes deficiency of an enzyme indices - plural of index; numbers used as indicators inert - chemically nonreactive infarction - dead muscle tissue often due to decreased blood flow from clogged coronary arteries infiltration - deposition and accumulation of an external substance within a cell, tissue, or organ insulin-like growth factor - peptide similar in chemical structure and activity to insulin insulin-like growth factor binding protein - a soluble protein that binds insulin-like growth factors and affects them at the cellular level intrinsic factor - glycoprotein that is secreted by the parietal cells of the gastric mucosa; necessary for the absorption of dietary vitamin B12 through the intestinal mucosa ion-exchange chromatography - separating components of a mixture based on different solubility characteristics and attraction to an electrically charged solid substance ionophore - substance that attracts charged molecules (ions)

ion-selective electrode (ISE) - electrode that measures the activity of one ion better than others iontophoresis - introduction of a drug through intact skin by the application of a direct electric current isoenzymes - forms of enzymes with different amino acid sequences giving unique properties but having the ability to catalyze similar chemical reactions jaundice - bilirubin deposits in the skin, mucous membranes, and eyes giving tissues a yellow appearance

Joint Commission on Accreditation of Healthcare Organizations (JCAHO) - accreditation organization for health-care facilities in order to continuously improve safety and quality of health care kernicterus - yellow staining of the lipid-rich meninges of the brain and spinal cord due to biliru-bin infiltrates ketoacidosis - the accumulation of keto acids in the blood causing metabolic acidosis laser - light amplification by stimulated emission of radiation; device using a high-energy beam of electromagnetic radiation law of mass action - the rate of any given chemical reaction is proportional to the product of the activities (or concentrations) of the reactants lecithin:cholesterol acyltransferase - an enzyme that esterifies a fatty acid to cholesterol Leydig cells - specialized interstitial cells of the testes surrounding the tubules that produce testosterone libido - sexual desire licensure - the process by which an agency of a state government grants permission to persons meeting predetermined qualifications to engage in a given occupation and/or to use a particular title; individuals who are not licensed cannot practice in that state linearity - relation of independent and dependent data points that produces a straight line lipemia - fatty accumulation in the blood giving cloudy appearance lipogenesis - formation of fats lipolysis - the catabolic degradation of triacylglycerol lipoprotein - protein combined with lipid components lipoprotein lipase - enzyme that catalyzes hydrolysis of triglycerides found on chylomicrons and VLDL lobules - the microscopic functional units of the liver lumen - space within a tube, such as a blood vessel or the esophagus luminescence - production of light without the production of heat luteal phase - second half of the female menstrual cycle following ovulation and the dominance of the corpus luteum lytic - rupturing or breaking down cell membranes M protein - paraprotein visible in protein elec-trophoresis causing a tall peak in the densitometry pattern, also called an M spike macroglobulinemia - disease of plasma cells marked by excess production of immunoglobulin M (IgM) macronutrient - a chemical element or substance, such as carbohydrates, proteins, and fats, required in relatively large quantities in the diet macrosomia - increased size and weight of the fetus malignant - characterized by completely unrestricted cell growth with a tendency to spread malnutrition - disease-promoting condition resulting from either an inadequate or excessive exposure to nutrients material safety data sheet - documents produced by the manufacturer of the chemical to provide safety information median - the middle value of a population medical decision level - concentration or limit at which test results are critically interpreted medical decision limit - the value for a test result that is used in making the diagnosis meningomyocele - congenital opening in the spinal cord membranes through which the cord protrudes; also called spina bifida mesoderm - middle of the three primary germ layers of an embryo, the source especially of bone, muscle, connective tissue, and dermis metabolic acidosis - acidosis resulting from increase in acids other than carbonic acid metabolic alkalosis - alkalosis in which plasma bicarbonate is increased with a proportionate rise in the plasma concentration of carbon dioxide

546 GLOSSARY

metastasis - tumor appearance in a different body site than the primary tumor of the same cell line metyrapone - metabolic hormone that inhibits biosynthesis of cortisol and corticosterone and is used to test for normal functioning of the pituitary gland; also known as metapyrone micelle - ultramicroscopic particle microalbuminuria - small amounts of albumin found in the urine, also called dipstick-negative increase in the excretion of albumin in urine microcytic - of smaller than normal size (red blood cells)

micronutrient - organic compound, such as a vitamin, or chemical element essential in minute amounts in the diet microvascular - pertaining to small blood vessels Mie scatter - large particles scattering light predomi-

nently in the forward direction mineralocorticoids - steroid molecules that influence blood electrolyte levels minimum effective concentration - the lower limit of the therapeutic range minimum toxic concentration - the lower limit of the toxicity range miscarriage - sudden unplanned evacuation of the uterus, ending pregnancy mixed venous oxygen saturation - capillary-to-

venous exchange of gases moiety - a portion of something that has been divided monensin - sodium ionophore used for ISEs; made from Streptomyces species monoclonal - arising from one cell line monosaccharides - simple carbohydrates that cannot be broken down to further sugars by hydrolysis morula - differentiated zygote that develops a cavity forming the blastocyst motor nerves - nerves that control movement mucin - a glycoprotein found in mucus, formed from mucigen and soluble in water multichannel - able to perform a variety of tests at the same time with separate dedicated instrument components multiple endocrine neoplasia - one of several inherited endocrine gland syndromes caused by a defect in tumor suppressor genes multiple myeloma - a malignant disease characterized by the infiltration of bone and bone marrow by neoplastic plasma cells multiple sclerosis - a progressive neurodegenerative disease affecting the axons of nerves in the area surrounding the ventricles of the brain but not the peripheral nerves myelin - phospholipid protein sheath of nerve cells myelodysplastic syndrome (MDS) - hematologic syndrome of inadequate bone marrow production of blood cells myocardium - heart muscle myxedema - puffiness in the face and surrounding the eyes

NAD - nicotinamide adenine dinucleotide NADH - reduced nicotinamide adenine dinucleotide phosphate

NADP - nicotinamide adenine dinucleotide phosphate NADPH - reduced nicotinamide adenine dinucleotide phosphate necrosis - death of tissue negative feedback - stabilizing a process by reducing its rate or output when its effects are too great neoplasia - accelerated new cell growth, either benign or malignant nephritis - inflammation of the kidney nephrolithiasis - presence of calculi in the urinary tract; urate nephrolithiasis indicates the presence of uric acid in the stone nephrotoxicity - damage to the kidneys neurohypophysis - the posterior or back portion of the pituitary gland nitrogen balance - difference between the amount of nitrogen ingested and that excreted noncompetitive immunoassay - immunoassay that does not contain reagent antigen competing with patient antigen nonprotein nitrogen - catabolites of protein and nucleic acid metabolism, including urea, ammonia, creatinine, creatine, and uric acid

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