| ||||
|
Amiloride Exchangers, which appear to be under separate genetic control, can be distinguished by their sensitivities to inhibition by amiloride or its analogs. The brush-border membrane Na'H' exchanger is less sensitive to inhibition than the basallateral exchanger. A similar observation has been made more recently in intestinal epithelial cells 26 ; whose plasma membrane exhibits polarity like the renal tubular cells. Interestingly, the exchanger found in the plasma membrane of other nonpolarized cells shows high sensitivity to amiloride inhibition similar to that of the basal-lateral exchanger of the cultured renal cells. From the available evidence, it appears that the plasma membrane of the nonpolarized cells such as fibroblasts possessesone type of Na'-H' exchanger and the brush-border membrane of the polarized cells such as intestinal and renal tubular cells possessesthe other type. For the sake of simplicity and convenience, we will call the former, "the plasma membrane type" and the latter, "the brush-border type." The work by Haggerty et al. 20-22 ; and Knickelbein et al. 26 ; demonstrates that both types of exchangers may coexist in a polarized cell. If one analyzes the data available in the literature on the characteristics of the Na + -H + exchanger in various cells in the light of the above classification, a particular pattern seems to emerge. The Na'-H' exchangers of the plasma membrane type and the brush-border type differ in their response to intracellular pH pHi ; 27 ; . Available data on the influence of pHi on the activity on these Na + -H' exchangers suggest that the plasma membrane type is better suited for the purpose of pHi regulation than the brush-border type. These two types of exchangers may also differ in their molecular weight. The importance of the exchanger in vital physiological functions of the cell has prompted many investigators to attempt to identify and purify the proteins involved in the exchange process 28-36 ; . The renal brush-border membrane Na + -H' exchanger has been the candidate for most of the molecular weight determination studies in the past. Despite the number of attempts, a definite conclusion regarding the molecular weight of this brush-border type Na'-H' exchanger is yet to emerge. The molecular mass of this exchanger determined in various studies has ranged anywhere between 25 and 100 kDa 29, 31-36 ; . However, a majority of studies seems to concur on a 65-75-kDa value 29, 32, 34-36 ; . On the contrary, Sardet et al. 37 ; have recently cloned a human growth factoractivatable Na + -H' exchanger which most likely represents the plasma membrane type and the amino acid sequence of the protein predicts a molecular mass of 100 kDa. Moreover, there are indications that the two types of Na'-H' exchangers may also differ in their regulatory mechanisms 24, 25, 3840 ; . The current investigation deals with the Na'-H' exchanger present in the human placental brush-border membrane. The purpose of the investigation was to determine if this exchanger is of the brush-border type or the plasma membrane type. This was done by comparing the sensitivities of the placental brush-border membrane Na + -H + exchanger and the renal brush-border membrane Na + -H' exchanger which represents the brush-border type ; to inhibition by amiloride analogs and other nonamiloride inhibitors. The results showed that there were important differences in the pharmacological properties of these exchangers. The renal brush-border membrane Na + H' exchanger was more sensitive to inhibition by clonidine than by cimetidine, while the placental brush-border membrane Na + -H + exchanger was more sensitive to inhibition by cimetidine than by clonidine. Similarly, a number of amiloride analogs were tested for their potencies to inhibit the renal. Fig. 4. Amiloride sensitivity depends upon the -subtype composition of the receptor. A, representative traces from receptors composed of 3, 2L, and one of the subtypes, as indicated, showing the current response to GABA alone or GABA 100 M amiloride from transfected cells voltageclamped at 50 mV. Standard horizontal bars indicate 2 s for all traces. GABA concentration was 1 M 6 ; , concentration-response relationships were constructed by measuring the peak current with coapplication of amiloride as a percentage of the response to GABA alone for each cell. Symbols and bars represent the mean S.E.M. Data were fit with a four-parameter logistic equation. IC50 values from the fits of combined data shown were 250.0 M 1 3 2L, N 4 ; , 231.3 M 2 3 2L, N 4 ; , 259.8 M 3 2L, N 3 ; , 333.2 M 4 3 2L, N 3 ; , 257.3 M 5 3 2L, N 5 ; , and 23.5 M 6 3 2L, N 4 ; . Hill numbers from these fits were 1.89 1 3 ; , 2.22 2 3 ; , 1.49 3 ; , 1.80 4 3 ; , 1.97 5 3 ; , and 0.96 6 3. Amiloride ingredientsThe case presented herein appears to be the only case of self-injury with a needle causing both a pneumothorax and cardiac penetration. This patient is most fortunate in that he did not suffer from any serious cardiac dysfunction on his initial presentation and in that he continues to do well from a medical standpoint despite apparent migration or embolization of the sewing needle. DIMENHYDRINATE DIMENOXADOL DIMENSION DIMEPHEPTANOL DIMEPHOSPHON DIMEPRANOL DIMEPREGNEN DIMEPROZAN DIMER * DIMER-X DIMERCAPROL dimercaptopropane-sulfonate-2, 3 sodium h.t. use IOCARMATE MEGLUMINE ANTIDOTES UNITIOL HEPATOTROPICS CHELATORS UNITIOL h.t. h.t. ESTROGEN-ANTAGONISTS PSYCHOSEDATIVES SPASMOLYTICS h.t. ANALGESICS h.t. h.t. ANTIEMETICS ANTIHISTAMINES-H1 SPASMOLYTICS ANALGESICS DIMETHOXANATE DIMETHOXYBENZOQUINONE-2, 5 DIMETHOXYFLAVONE-5, 7 dimethoxyiodophenylaminopropane dimethpyrindene DIMETHYL-DISULFIDE DIMETHYL-FUMARATE DIMETHYL-PAMIDRONATE DIMETHYL-PHTHALATE DIMETHYL-SELENIDE dimethyl-sulfoxide DIMETHYLACETAMIDE DIMETHYLACRYLAMIDE-N, N DIMETHYLACRYLSHIKONIN-BETA, BETA DIMETHYLADIPIMIDATE DIMETHYLADRENALINE use was SUCCIMER DIMERCAPTOSUCCINATE dimethylamantadine DIMETHYLAMILORIDE DIMETHYLAMINE dimethylaminoantipyrine h.t. h.t. h.t. CORTICOSTEROIDS ESTROGENS PSYCHOSTIMULANTS ANTIDEPRESSANTS BROMPHENIRAMINE h.t. h.t. h.t. ANTICONVULSANTS PSYCHOSTIMULANTS PSYCHOTONICS DIURETICS PSYCHOTONICS PSYCHOSTIMULANTS MEBOLAZINE COCCIDIOSTATICS PROTOZOACIDES DIMETICONE SIMETHICONE DIMETINDENE RADIOPAQUES FUNGICIDES QUINISOCAINE PROGESTOGENS INSECTICIDES LOCAL-ANESTHETICS ANTIHISTAMINES-H1 HYPOTENSIVES DIMETOFRINE DIMETOTIAZINE DIMETHYLAMINOAZOBENZENE dimethylaminophenazone DIMETHYLAMINOPHENOL DIMETHYLAMINOPURINE-6- ARABINOSIDE DIMETHYLAMINOPYRIDINE-4 dimethylarsinic-acid DIMETHYLBARBITURATE-1, 3 DIMETHYLBARBITURATE-1, 5 DIMETHYLBARBITURATE-5, 5 DIMETHYLBENZAMIL-2 + , 4 + DIMETHYLBENZANTHRACENE DIMETHYLBUMETANIDE DIMETHYLBUSULFAN dimethylbutylbarbiturate dimethylcyclodextrin-beta DIMETHYLDAUNORUBICIN-N, N DIMETHYLDIOCTADECYL- AMMONIUM BROMIDE DIMETHYLDITHIOCARBAMATE DIMETHYLDODECANAMINE DIMETHYLDOPAMINE-N, N dimethyldoxorubicin-n, n DIMETHYLELLAGATE-3, 3 + h.t. h.t. use ANTISEPTICS DOPAMINERGICS AD-280 h.t. use use h.t. h.t. CYTOSTATICS DIBERAL CYCLODEXTRIN-BETA-DIMETHYL ANTIBIOTICS CYTOSTATICS ADJUVANTS SURFACTANTS use h.t. h.t. h.t. use AMINOPHENAZONE ANTIDOTES VIRUCIDES NEUROMUSC.BLOCKER- ANTAGONISTS CACODYLATE use AMINOPHENAZONE h.t. h.t. use ANTIANEMICS ANTISICKLINGS SYMPATHOMIMETICS MEMANTINE use DIMETHYLSULFOXIDE h.t. h.t. ANTIPSORIATICS ANTIBIOTICS CYTOSTATICS use use DOI DIMETINDENE h.t. h.t. ANTITUSSIVES PHYTONCIDES and amiodarone. The company develops and markets these drugs by leveraging its expertise in chiral chemistry and pharmacology with its experience in conducting clinical trials and seeking regulatory approvals for new drugs. With 136 months follow-up. Radiology 1993; 188: 381387. Whyman MR, Fowkes FG, Kerracher EM, et al. Randomised controlled trial of percutaneous transluminal angioplasty for intermittent claudication. Eur J Vasc Endovasc Surg 1996; 12: 167172. Bosch JL, Hunink MG. Meta-analysis of the results of percutaneous transluminal angioplasty and stent placement for aortoiliac occlusive disease. Radiology 1997; 204: 8796. Capek P, McLean GK, Berkowitz HD. Femoropopliteal angioplasty. Factors influencing long-term success. Circulation 1991; 83: I-70I-80. 43. Hunink MG, Wong JB, Donaldson MC, Meyerovitz MF, de Vries J, Harrington DP. Revascularization for femoropopliteal disease. A decision and cost-effectiveness analysis. JAMA 1995; 274: 165171. Stonebridge PA, Naidu S, Colgan MP, Moore DJ, Shanik DG, McCollum PT. Tibial and peroneal artery bypasses using polytetrafluoroethylene PTFE ; with an interposition vein cuff. J R Coll Surg Edinb 2000; 45: 1720. Mannick JA, Whittemore AD, Donaldson MC. Clinical and anatomic considerations for surgery in tibial disease and the results of surgery. Circulation 1991; 83: I-81I-85. 46. Verhelst R, Bruneau M, Nicolas AL, et al. Popliteal-to-distal bypass grafts for limb salvage. Ann Vasc Surg 1997; 11: 505509. Faries PL, Arora S, Pomposelli FB Jr., et al. The use of arm vein in lower-extremity revascularization: results of 520 procedures performed in eight years. J Vasc Surg 2000; 31: 5059. Wolfle KD, Bruijnen H, Reeps C, et al. Tibioperoneal arterial lesions and critical foot ischaemia: successful management by the use of short vein grafts and percutaneous transluminal angioplasty. Vasa 2000; 29: 207214. Eagle KA, Brundage BH, Chaitman BR, et al. Guidelines for perioperative cardiovascular evaluation for noncardiac surgery. Report of the American College of Cardiology American Heart Association Task Force on Practice Guidelines. Committee on Perioperative Cardiovascular Evaluation for Noncardiac Surgery. Circulation 1996; 93: 12781317. Mann MJ. Gene therapy for peripheral arterial disease. Mol Med Today 2000; 6: 285291. Chawla PS, Keelan MH, Kipshidze N. Angiogenesis for the treatment of vascular diseases. Int Angiol 1999; 18: 185192. Baumgartner I, Isner JM. Gene therapy for peripheral vascular disease. Isr Med Assoc J 2000; 2: 2732. Schratzberger P, Schratzberger G, Silver M, et al. Favorable effect of VEGF gene transfer on ischemic peripheral neuropathy. Nat Med 2000; 6: 405413. Isner JM. Manipulating angiogenesis against vascular disease. Hosp Pract 1999; 34: 6980. Kalka C, Takahashi T, Masuda H, Asahara T, Isner JM. Vascular endothelial factor VEGF ; : therapeutic angiogenesis and vasculogenesis in the treatment of cardiovascular disease. Med Klin 1999; 94: 193201. Rivard A, Silver M, Chen D, et al. Rescue of diabetes-related impairment of angiogenesis by intramuscular gene therapy with adenoVEGF. J Pathol 1999; 154: 355363. Isner JM, Walsh K, Symes J, et al. Arterial gene transfer for therapeutic angiogenesis in patients with peripheral artery disease. Hum Gene Ther 1996; 7: 959988. Isner JM, Walsh K, Symes J, et al. Arterial gene therapy for therapeutic angiogenesis in patients with peripheral artery disease. Circulation 1995; 91: 26872692. Spittell PC. Peripheral vascular disease. In: Murphy J, editor. Mayo Clinic cardiology review. 2nd ed. Philadelphia: Lippincott Williams and Wilkins, 2000: 10131024. 60. Working Party on Thrombolysis in the Management of Limb Ischemia. Thrombolysis in the management of lower limb peripheral arterial occlusion--a consensus document. J Cardiol 1998; 81: 207218. ADDRESS: Debabrata Mukherjee, MD, Director, Peripheral Vascular Interventions, Division of Cardiology, 1500 East Medical Center Drive, University of Michigan, Ann Arbor, Michigan 48109-0022; e-mail dmukherjee pol and cordarone, for example, amiloride diuretic. High doses are relatively contraindicated in patients with hyperlipidemia, gout, and diabetes. Same as amiloride Same as amiloride. Aldosterone controls sodium balance by regulating an amiloride-sensitive, electrogenic sodium transport across the renal tubular epithelium of the aldosterone-sensitive distal nephron ASDN ; which expresses both mineralocorticoid MR ; and glucocorticoid receptors GR ; . Free aldosterone plasma concentrations vary within a large range from 0.05nM to 15 nM ; function of circadian rhythm, salt intake and volume depletion, whereas free plasma cortisol or corticosterone circulates at much higher concentrations 100 fold ; and varies in function of circadian rhythm and stress. Mineralocorticoid specificity is insured by high level of 11b-hydroxysteroid dehydrogenase type2 11b-HSD2 ; , which metabolizes cortisol or corticosterone into inactive metabolites preventing illicit occupations of MR and or GR. The fractional occupancy of MR and GR by aldosterone mediating the mineralocorticoid-dependent sodium transport in the ASDN cannot be studied in vivo. To answer this question, we took advantage of a novel mouse cortical collecting duct cell line mCCDcl1 ; , which expresses significant levels of MR and GR and a robust aldosterone sodium transport response. It permits to carry out dose-response curves over a large range 0.1nM-300nM ; of agonist concentrations aldosterone, corticosterone and dexamethasone ; and to quantitate the affinities and number of binding sites of these ligands for MR and GR. Aldosterone elicited a biphasic response: low doses K1 2 ~ 0.5 nM ; induced a transient and early increase of sodium transport peaking at 3h ; , whereas high doses K1 2 ~ entailed a ~3-fold larger, long lasting response. At 3 h, the corticosterone dose-response curve was shifted to the right by more than two log concentration, an effect which was fully reverted in the presence of the 11b-HSD2 inhibitor carbenoxolone. No significant responses were observed at 6 and 24 h. Low doses of dexamethasone 0.1 to 1 nM ; failed to induce an early response, but high doses elicited a long lasting response K1 2 ~ similar to that observed for high aldosterone concentrations. Within the physiological range of aldosterone concentrations, sodium transport is mainly controlled by MR occupancy, but higher physiopathological ; concentrations are able to further increase sodium transport through occupancy of GR. According to published values for plasma aldosterone and corticosterone, a model of MR vs occupancy is proposed during circadian cycles, chronic salt restriction and stress and elavil. Antifungal Drugs 3 0.8 0.0 0.6 0.0 0.0 0.0 0.0 0.0 0.4 9.6 0.0 0.0 0.0 10.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.2 0.0 2.2 6.7 0.0 0.0 3.4 0.4 24.7. High affinity [3HJbenzamil-binding site putative Na + chanor nel. NMBA was used to photoaffinity label and identify the putative channel in bovine kidney cortical membranes. The membranes were photolabeled with 25 nM NMBA for varying periods of time Fig. 4A ; , or for 10 min with varying concentrations of NMBA B ; .The photolabeled proteins were analyzed by SDS-PAGE and immunoblotting. A major band of photoincorporation was seen with an apparentM , of 130, 000. The specificity of photoincorporation was shown by photolabeling with 5 nM NMBA in the presence or absence of varying concentrations of benzamil, which was added to inhibit specific photoincorporation of NMBA into the channel C ; .In addition, polypeptides with apparent M , of 75, 000 to 80, 000 and 50, 000 were specifically, but weakly, labeled with NMBA. The polypeptide labeled with NMBA at the top of the resolving gel in Fig. 4 is likely a result of protein aggregation. Identification of Polypeptide Subunits of the Putative Epithelial Nu + Channel in A6 Cells-A similar set of experiments was performed to characterize amiloride-binding components of the Na + channel in the amphibian epithelial cell line A6. We first tested if the new amiloride analog we synthesized NMBA ; is a potent inhibitor of amiloride-sensitive SCC, which is ameasure of net transepithelial Na + transport across A6 cells 7 ; . The concentration of NMBA required to inhibit 50% of the amiloride-sensitive SCC ICB0 ; 80 nM n was NMBA, like benzamil IC50 90 nM, n 3 ; is a more potent inhibitor than amiloride IC5o 350 nM, n 6 ; . The ICsoof amiloride is in excellent agreement with previous studies 1, 18, 21 ; . The binding of [3H]benzamilto the microsomal membranes from A6 cells grown on collagen-coated filters was also examined. A single class of high affinity-binding sites was observed with a Kd of The number of binding sites was 8 pmol mg protein. The Kd is in good agreement with the ICB0of 90 nM observed in transport studies. The difference in K d binding studies ; and IC5o transport studies ; is likely due to thepresence of a high 110 mM ; concentration of Na + used in the transport assay. It is well known that decreasing the extracellular Na + concentration will result in a decrease in the IC50 of amiloride or its analogs ; 18, 24 ; . These data indicate that benzamil isbinding to the Na and endep. Amiloride drug interactionsThere are no specific monitoring requirements for these drugs beyond those used for patients with HTN. HTN is discussed in Chapter 38 and caduet. Coombs ; test. The broad-spectrum antiglobulin Coombs ; reagent detects both immunoglobulin and complement components principally C3 ; . More specific reagents that detect only IgG or complement may be used to refine the pattern of RBC coating. Three major patterns of direct antiglobulin reaction have been noted in warm-antibody AIHA--RBCs coated with IgG alone, RBCs coated with IgG plus complement components, and RBCs coated with complement components alone. In patients with warm-antibody AIHA, the autoantibody exists in a reversible, dynamic equilibrium between RBCs and plasma. If sufficient free autoantibody is present in the plasma or serum of the patients, it may be detected by the indirect antiglobulin test. In general, the presence of plasma autoantibody may be viewed as overflow or excess above that bound to RBCs. Thus, patients with a positive indirect antiglobulin test caused by a warm-reactive autoantibody must also have a positive direct antiglobulin test. A patient who exhibits a positive indirect antiglobulin reaction but a negative direct antiglobulin reaction probably does not have an autoimmune process but rather an alloantibody stimulated by prior transfusion or pregnancy. Cryopathic Hemolytic Syndromes: Direct Agglutinins and Hemolysins Direct agglutinins, as the name implies, directly agglutinate normal or autologous human RBCs. These antibodies, largely of the IgM class, are present in patients with cold agglutinin disease. Cold agglutinins cause RBCs to agglutinate maximally at 0C to 32F to 41F ; . In patients with chronic cold agglutinin disease, the serum cold agglutinin titers are commonly 1: 10, 000 or higher and may reach 1: 000, 000 or more. The direct antiglobulin test is positive only with anticomplement reagents. This is because the cold agglutinin autoantibody molecules readily dissociate from the RBCs during the washing steps of the antiglobulin test procedure and are not detected. In contrast, complement components are covalently bound to target RBCs and cannot be washed off. In PCH and Donath-Landsteiner hemolytic anemia, the patient's serum contains hemolysins, antibodies that lyse RBCs in the presence of complement. The direct antiglobulin reaction may be positive during or briefly after an acute attack, because of the coating of surviving RBCs with complement. The antibody is a nonagglutinating IgG that binds only in the cold. It is detected by the biphasic Donath-Landsteiner test, in which the patient's fresh serum is incubated with RBCs initially at 4C 39F ; and then warmed to 37C 98.6F ; . Intense hemolysis follows. Drug-Induced Immune Hemolytic Anemia The serologic findings in drug-induced immune hemolytic anemia vary according to the mechanism, because . Florida was one of the first states to specifically address the issue of Internet prescribing, by promulgating Rules 64B8-9.014, FAC and 64B15-14.008, FAC. These rules prohibits doctors from prescribing to patients without performing an adequate history and physical. There are exceptions for on call and cross coverage and for emergency situations. Prescribing of controlled substances by registered interns, residents, and fellows, Rule 64B8-6.010, FAC; Standards for Prescribing Obesity Drugs, Rules 64B8-9.012, FAC and 64B15-14.004, FAC. Suggestions for Safe Practice and Avoiding Regulatory Problems Allopathic physicians, M.Ds. ; by far account for the greatest number of controlled substance prescriptions written each year. During my 17 years of observing the Board of Medicine hear more than 4, 000 disciplinary cases, I have seen good practitioners being disciplined because they did not know the rules, kept poor documentation in the charts, or were not paying attention in their busy practices. Controlled substance scenarios that typically end up badly for licensees include the following: Internet prescribing, Self-prescribing controlled substances, Selling scripts, Medication error wrong strength, Prescribing without an examination, Not paying attention to drug history in chart, and Pre-signing scripts. Based upon the above history and perspective, the following outline of practical suggestions and observations are respectfully offered. For many, this is familiar ground; however, I hope there will be something new for the prescribing practitioner. 1.BE PREPARED TO IDENTIFY AND DEAL WITH THE MANIPULATIVE PATIENT Practitioners should be able to recognize behaviors that identify a patient as a likely drug seeker. These patients may give the practitioners the following signals: "I can only take Percocet, the other medications don't work for me." "I can't afford any tests, just give me the same meds I have been taking." "I lost my medical records from my prior treater, and I forgot his name" " I lost my prescription for Lortab .again." There are several tools for handling these patients. Use a detailed informed consent form that alerts the new patient prior to the first encounter of your policy on prescribing controlled substances. This will not only deter drug-seeking behavior but may also deter those who are only seeking your care as a source for controlled substances. If the patient demands prescriptions which you do not find are indicated, you may advise the patient that your medical license does not allow you to prescribe a medication unless a clear medical need is documented in the patient's chart. Listen to your pharmacists. Document, and If all else fails, you can use a 30-day letter terminating care with that patient and ascorbic. Tell your doctor if you use any of the following drugs: heparin; aspirin or other nsaids non-steroidal anti-inflammatory drugs ; such as celecoxib celebrex ; , diclofenac voltaren ; , ibuprofen motrin, advil ; , indomethacin, naproxen aleve, naprosyn ; , piroxicam feldene a diuretic water pill ; such as spironolactone aldactone ; , triamterene dyrenium, dyazide, maxzide ; , amiloride midamor ; , or eplerenone inspra a potassium supplement such as klor-con, k-dur, k-tab; an ace inhibitor such as benazepril lotensin ; , lisinopril prinivil, zestril ; , enalapril vasotec or blood pressure medicine such as candesartan atacand ; , losartan cozaar ; , telmisartan micardis.
|