Prandin
By A. Tom. LeTourneau University.
By the aid of the two constants A and N (for a particular prism) the angle α has been converted into the refractive index directly and the scale of the instrument has been duly calibrated and printed accordingly cheap prandin 2 mg fast delivery diabetes mellitus type 1 icd 9 code. When C is made to rotate gradually the critical ray (E) falls on the cross hair (H) of the telescope (F). At this juncture the value of the refractive index of the liquid (n) can be measured directly from the scale (G). It is, however, important to mention here that the calibration of Abbe’s refractometer may be checked periodically by making use of standard liquids whose refractive index are stated in theEuropean Pharmacopoea (as Reference Liquids). Based on this physical characteristic it is possible to ascertain the purity of this volatile oil precisely and accurately. Materials Required : Abbe’ refractometer, volatile oil, xylene, capillary tubes ; Procedure : In order to obtain precise and accurate measurements the prism case of Abbe’ refractometer is attached to a thermostat bath whose temperature is previously maintained at 25°C. Open the prism box gently and place a few drops of pure volatile oil on the lower prism with the help of a capillary tube and finally close the box. The mirrors are duly adjusted so as to obtain a bright illumination of the field of view. The knurled knob is turned gradually until the field of view displays a dark and light zone. In case, a col- oured-fringe is observed between the two zones it becomes necessary to adjust the Amici prisms carefully to achieve a sharp and black boundary. It is important to adjust this on the cross hair and finally the reading of refractive index is noted. After use, the prism box is opened and cleaned thoroughly with a lens cleansing 25 tissue moistened with xylene/acetone. It has been observed that a number of monomers usually hold all the hydrocarbon chains together specifically in the centre of the micelle which are ultimately responsible for minimising the free energy of the system. Using Abbe’ refractometer measure the refractive indices of all the above six solutions besides the stock solution (25%) at 25°C. Explain the following with reference to ‘Refractometry’ : (a) Snell’s Law, (b) Critical angle vis-a-vis Refractive index, (c) Molar refractivity, and (d) Atomic refractivities. Describe the optical system of Abbe’s Refractometer, its optical path for upper prism and its operational procedure. In fact, there exists an indefinite number of planes that pass through the line of propagation, and an ordinary light usually vibrates in all the planes. Under certain specific circumstances, the vibrations may all be restricted to one direction only, in the perpendicular plane and this is termed as plane-polarized light. Thus, an ordinary light (unpolarized light) gets converted into a plane-polar- ized light by simply passing it through a lens made of the above cited materials and traditionally called a Nicol prism (after William Nicol-the inventor). Therefore, an optically active substance is one that rotates the plane of polarized light. In other words, certain specific substances by virtue of their internal structure may be able to transmit only such vibrations that are oriented along certain directions and entirely block vibrations in other directions. However, it is worth mentioning that the plane-polarized beam is the vector-sum of these two components. In other words, when a polarized light, oscillating in a specific plane, is made to pass through an optically active substance, it happens to emerge oscillating in an altogether different plane. Such types of molecules usually exist in two stereoisomeric forms as mirror images of each other. In the same vein, the example [ii (b)] represents 1-2 methy1-1-butanol ; a product derived from fusel oil. Non-superimposability and Optical Activity : Interestingly, in these two specific examples of lactic acid (d- ; and 1-isomers) and 2-methy-1-butanol (d- ; and 1-isomers) one criterion is common i. In other words, such compounds whose mirror images display non- superimposability exhibit optical activity. Thus, a pure sample of a single enantiomer must fulfil the following three important characteristic features, namely : (a) No molecule can serve as the mirror image of another molecule, (b) Exact cancelling out of rotations (of plane of polarized light) do not occur, and (d) Net result is offered in terms of the ‘optical activity’. Principle : The underlying principle of a polarimeter is that light from the source, usually a sodium vapour lamp, first gets collimated at A, and subsequently falls upon polarizer B (acalcite prism). The polarizer permits only the light polarized in a particular direction to pass it.
Most diuretcs increase urine volume by inhibitng the reab- sorpton of Sodium and chloride ions in the renal tubule; they also modify renal handling of potassium buy prandin 1 mg with mastercard diabetes mellitus in older dogs, calcium, magnesium and urate. Osmotc diuretcs act diferently; they cause an increase in urine volume by an osmotc efect. Although loop diuretcs are the most potent their duraton of acton is relatvely short, whilst thiazide diuretcs are moder- ately potent but produce diuresis for a longer period. Carbonic anhydrase inhibitors are weak diuretcs which are rarely, used for their diuretc efect and are principally used to lower intraocular pressure in glaucoma. Electrolyte Imbalance: The adverse efects of diuretc therapy are mainly due to the fuid and electrolyte imbalance induced by the drugs. The risk of hypoka- laemia, which may occur with both thiazide and loop diuretcs, depends more on the duraton of acton than on potency and is thus greater with thiazides than with loop diuretcs (when given in equipotent doses). Other electrolyte disturbances include hypercalcaemia (thiazides), hypocalcaemia (loop diuretcs) and hypomagnesaemia (thiazide and loop diuretcs). Symptoms of fuid and electrolyte imbalance include dry mouth, thirst, gastrointestnal disturbances (including nausea, vomitng), weakness, lethargy, drowsiness, restlessness, seizures, confusion, headache, muscle pains or cramps, hypo- tension (including postural hypotension), oliguria, arrhyth- mias. Elderly: The elderly are more susceptble to electrolyte imbalance than younger patents. Treatment should begin with a lower inital dose of the diuretc (commonly about 50% of the adult dose) and then adjusted carefully according to renal functon, plasma electrolytes and diuretc response. They produce diuresis within 1-2 h of oral administraton and most have a duraton of acton of 12-24 h. Thiazide diuretcs are used in the management of oedema associated with mild to moderate congestve heart failure, renal dysfuncton or hepatc disease; however, thiazides are not efectve in patents with poor renal functon (creatnine clear- ance of less than 30 ml per min). In hypertension, a thiazide diuretc is used at a low dose to lower blood pressure with very litle biochemical disturbance; the max. Higher doses should not be used because they do not neces- sarily increase the hypotensive response but may cause marked changes in plasma potassium, magnesium, uric acid, glucose and lipids. If a thiazide alone does not lower blood pressure adequately, it may be used in combinaton with another ant- hypertensive such as a beta-adrenoceptor antagonist. Urinary excreton of calcium is reduced by thiazide diuretcs and this property is occasionally utlized in the treatment of idiopathic hypercalciuria in patents with calcium-containing calculi. Paradoxically, thiazide diuretcs are used in the treat- ment of diabetes insipidus, since in this disease they reduce urine volume. Thiazide diuretcs, especially in high doses, produce a marked increase in potassium excreton which may cause hypoka- laemia; this is dangerous in patents with severe coronary artery disease and those being treated with cardiac glyco- sides. In hepatc failure hypokalaemia can precipitate enceph- alopathy, partcularly in alcoholic cirrhosis. Potassium-sparing diuretcs are used as a more efectve alternatve to potas- sium supplements for preventon of hypokalaemia induced by thiazide diuretcs; however supplementaton with potas- sium in any form is seldom necessary with the smaller doses of diuretcs used to treat hypertension. Loop Diuretcs: Loop diuretcs, or high-ceiling diuretcs, such as furosemide, are the most potent and rapidly produce an intense dose-de- pendent diuresis of relatvely short duraton. Oral furosemide produces diuresis within 30-60 min of administraton, with the max. They are also used to treat oedema associated with renal and hepatc disorders and are used in high doses in the management of oliguria due to chronic renal insufciency. Because of their shorter duraton of acton, the risk of hypoka- laemia may be less with loop diuretcs than with thiazide diuretcs; if required, potassium-sparing diuretcs may be used for preventon of hypokalaemia. Loop diuretcs may cause hypovolaemia and excessive use can produce severe dehydraton with the possibility of circulatory collapse. Rapid high-dose injecton or infusion of furosemide may cause tnnitus and even permanent deafness. Potassium-Sparing Diuretcs: Potassium-sparing diuretcs include amiloride and spironolac- tone; they are weak diuretcs and reduce potassium excreton and increase Sodium excreton in the distal tubule. Amiloride acts about 2 h afer oral administraton, reaching a peak in 6-10 h and persistng for about 24 h. Spironolactone, which acts by antagonising aldosterone, has a relatvely slow onset of acton requiring 2-3 days to achieve max.
Multifunctional host defense peptides: intracellular-targeting antimicrobial peptides cheap prandin 2mg fast delivery diabetic diet how many carbs per day. Antimicrobial and host-defense peptides as new anti-infective therapeutic strategies. Differential scanning calorimetry and X-ray diffraction studies of the specifcity of the interaction of antimicrobial peptides with membrane-mimetic systems. Antimicrobial peptides: linking partition, activity and high membrane-bound concentrations. The antimicrobial activity of Sub3 is dependent on membrane binding and cell-penetrating ability. Elevated expression of phos- phatidylserine in the outer membrane leafet of human tumor cells and recognition by activated human blood monocytes. Changes in elec- tric charge and phospholipids composition in human colorectal cancer cells. Structural features of helical antimicrobial peptides: their poten- tial to modulate activity on model membranes and biological cells. Hydrophobicity, hydrophobic moment and angle subtended by charged residues modulate antibacterial and haemolytic activity of amphipathic helical peptides. Dathe M, Schumann M, Wieprecht T, Winkler A, Beyermann M, Krause E, Matsuzaki K, Murase O, Bienert M. Peptide helicity and membrane surface charge modulate the balance of electrostatic and hydrophobic interactions with lipid bilayers and biological membranes. Prediction of antibac- terial activity from physicochemical properties of antimicrobial peptides. A synergism between tem- porins toward Gram-negative bacteria overcomes resistance imposed by the lipopolysac- charide protective layer. Maqueda M, Sanchez-Hidalgo M, Fernandez M, Montalban-Lopez M, Valdivia E, Martinez-Bueno M. Diversity of entero- coccal bacteriocins and their grouping in a new classifcation scheme. Molecular characterization of genes involved in the produc- tion of the bacteriocin leucocin A from Leuconostoc gelidum. Natural antimicrobial peptides from bacteria: characteristics and potential applications to fght against antibiotic resistance. Structural and functional diversity of microcins, gene-encoded antibacterial peptides from enterobacteria. Microcin E492, a channel-forming bacteriocin from Klebsiella pneumoniae, induces apoptosis in some human cell lines. Antibacterial and antitumori- genic properties of microcin E492, a pore-forming bacteriocin. Effcacy of microcin J25 in biomatrices and in a mouse model of Salmonella infection. The cyclic structure of microcin J25, a 21-residue peptide antibiotic from Escherichia coli. Microcin J25 has a threaded sidechain-to-backbone ring structure and not a head-to-tail cyclized backbone. Structure of ther- molysin cleaved microcin J25: extreme stability of a two-chain antimicrobial peptide devoid of covalent links. Microcin J25 triggers cytochrome c release through irreversible damage of mitochondrial proteins and lipids. Molecular mechanism of transcription inhibition by peptide antibiotic Microcin J25. Effects of the antibiotic peptide microcin J25 on liposomes: role of acyl chain length and negatively charged phospholipid. The antibacterial action of microcin J25: evidence for disruption of cytoplasmic membrane energization in Salmonella newport. The role of bacterial membrane proteins in the internalization of microcin MccJ25 and MccB17. Biosynthesis, immunity, regu- lation, mode of action and engineering of the model lantibiotic nisin.
Stability Testing of Drug Substances and Drug Products 63 A packaging site change for other than solid oral dos- G order prandin 1 mg without prescription blood sugar 71. The stability data packages for changes in container and closure of a drug product vary. Change in Testing Laboratory determining the stability data package recommendation is whether the protective properties of the container and clo- An analytical testing laboratory site change may be sub- sure system are affected by the proposed change. Protective mitted as a Changes Being Effected Supplement under properties of the container and closure system include, but certain circumstances. Changes that may affect these properties should be supported by a greater amount D. A solid dosage form will A change limited to the manufacturing process of the drug generally be less affected by a container change than a product, such as a change in the type of equipment used, liquid dosage form. Because considerably more informa- can be supported by the submission of sufficient data to tion will be needed to document a container and closure show that such a change does not alter the characteristics change than just stability data, applicants are encouraged or compromise the stability of the drug product. Such a modification to the approved stability protocol nature of the reprocessing procedure and any specific should be submitted as a Prior Approval Supplement. The effect it might have on the existing stability profile of the justification may include a demonstrated history of satis- drug. The expiration dating period for a reprocessed batch factory product stability, which may in turn include, but should not exceed that of the parent batch, and the expi- not be limited to, full long-term stability data from at least ration date should be calculated from the original date of three production batches. For example, drug products with an expiration procedure, which can range from repackaging a batch when dating period of less than 18 months should be tested at packing equipment malfunctions to regrinding and recom- quarterly intervals, products with an expiration dating pressing tablets. The appropriate chemistry review team period of 18 but not more than 30 months should be tested should be contacted to determine whether the reprocessing semiannually, and products with an expiration dating procedure is acceptable. Any batch of the drug product that period of 36 months or longer should be tested annually. Quinine actinometry as a method for calibrat- ing ultraviolet radiation intensity in light-stability testing of pharmaceuticals, Drug Dev. The design assumes that the stability of the inter- technological and biological products, some degradation mediate condition samples is represented by those at the products may be active. Examples of complex dosage forms Active ingredient that is intended to furnish pharmacolog- include modified-release dosage forms, metered-dose ical activity or other direct effect in the diagnosis, cure, inhalers, transdermal patches, and liposome preparations. Impurity — Any entity of the drug substance (bulk mate- Date of Production — Date that the first step of manu- rial) or drug product (final container product) that is not facture is performed that involves the combining of an the chemical entity defined as the drug substance, an active ingredient, antioxidant, or preservative with other excipient, or other additives to the drug product. For a biological product subject to but for which manufacture is critical to the successful pro- licensure, see the definition of date of manufacture in duction of the drug substance or the drug product. Modified release solid oral dosage forms life and retest period, which are claimed in the submission include both delayed and extended release drug products. The focus may instead be on ensuring the conditions that support the proposed retest date. Data on specificity of the assay, the completeness of the investiga- the drug product stored in the proposed container and tion of routes of degradation, and the use, if necessary, of closure for marketing under storage conditions that sup- identified degradants as indicators of the extent of degra- port the proposed shelf life. At a Random Sample — Selection of units chosen from a larger subsequent sampling point, different sets of samples of population of such units so that the probability of inclusion the total number would be tested. In a simple random the stability of the samples tested represents the stability sample, each unit has an equal chance of being included. The differences in the samples for the same Random samples are usually chosen with the aid of tables drug product should be identified as, for example, cover- of random numbers found in many statistical texts. Matrixing applicant relies in seeking approval of its abbreviated can cover reduced testing when more than one variable is application. This potential complexity precludes inclusion of spe- material is still suitable for use. In every case, it is essential specifications and therefore be acceptable for use in the that all batches are tested both initially and at the end of manufacture of a given drug product, provided that it has the long-term testing period. Examples of simple dosage forms passage of a solvent, such as water contained therein, but include immediate-release solid oral dosage forms; for prevents the passage of the dissolved substance or solute, example, tablets, capsules, semisolid dosage forms, and oral thus resulting in an increased concentration of the latter and parenteral solutions. It may also permit the ingress of foreign volatile rently marketed dosage forms and the ever-increasing com- materials.
