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MicroRNAs are small noncoding RNAs that have emerged as important regulators of many biological and pathological processes, including those relevant to the development of the heart and cardiovascular disease. Several recent studies using genetic models and profiling of microRNAs have established the important role of these novel molecules in a number of conditions of the heart. These studies have led to a flurry of research focussing on the identification of new therapeutic targets for the treatment of cardiac disease, as well as the identification of potential biomarkers for early diagnosis of heart disease. These early reports have stimulated much interest in microRNAs and indeed other non-coding RNAs in the broader context of cardiovascular disease. This work has been further investigated as a result of ease with which the levels of these molecules can be modulated both in vitro but also in animal disease models. Furthermore, a number of studies have specifically looked at the prognostic potential of these microRNAs as biomarkers of cardiovascular disease. This review is focused on highlighting some of the novel aspects of recent research in the area of the development of new therapeutics and better diagnostics for cardiovascular disease.

The renewed interest in inhalation delivery over recent years has led to an expansion in the understanding of lung pharmacokinetics. Historically optimisation of inhaled drugs focused largely on development of material properties, consistent with achieving a good lung deposition, alongside demonstrating appropriate in vivo efficacy with little understanding of the relationship to pharmacokinetics in the lung. Recent efforts have led to an increased understanding of lung concentrations and how to maximise exposure in order to achieve the desired pharmacological response at a dose consistent with development of an inhaled product. Although there is a prerequisite for excellent potency in inhalation delivery, it is essential that this be combined with pharmacokinetic properties that allow sufficient free concentration at the effect site in lung to exert the pharmacological response for an appropriate dosing interval. Increases in basicity, polarity and/or decreases in aqueous solubility can extend pharmacokinetic duration and assist in finding the right balance between lung and systemic exposure. Current evidence suggests there are similarities in lung retention in rat and dog and that animal lung concentration data can enable pharmacokinetic-pharmacodynamic relationships to be derived thus providing more confidence in the requirements for man. Although inhaled delivery is challenging from a pharmacokinetic point of view, direct evaluation of exposure in the target organ has enabled further understanding of the drivers for drug disposition and highlighted the need for further development of predictive lung pharmacokinetic tools in the future.

Tubular dysfunction is an important early manifestation of diabetic nephropathy. Reduced renal expression of organic cation transporters (OCTs) potentially contributes to impaired cation clearance in diabetes. This study examines the role of advanced glycation end-products (AGEs) in mediating these changes. Experimental diabetes was induced with streptozotocin (55 mg/kg). Rats were randomly treated with the AGE inhibitor aminoguanidine for 32 weeks. In a second protocol, diabetic rats were followed with and without low-dose insulin therapy (2 U/day) for 4 weeks. Expression of OCTs was determined by real-time RT-PCR (reverse transcription-polymerase chain reaction) and Western blotting. As a marker of cation transport, the fractional clearance of endogenous N-methylnicotinamide (NMN) was determined by high-performance liquid chromatography. Both short- and long-term diabetes was associated with reduced gene and protein expression of the three renal OCT isotypes. This was associated with a reduction in the fractional clearance of NMN compared with control animals by over 50%. These changes correlated with the accumulation of renal and plasma AGEs. Treatment with the AGE inhibitor aminoguanidine restored the expression of OCT-2 and OCT-3 in diabetic animals and normalized renal NMN clearance. NMN clearance was also improved in diabetic animals receiving low-dose insulin, correlating with a reduction in AGEs and improvement in effective renal plasma flow. These studies demonstrate an early impairment of expression of OCTs and cation clearance associated with diabetes. These changes correlate with the accumulation of AGEs and may be partly attenuated by an AGE inhibitor, implicating a role for AGEs in organic cation transport.

Multidrug resistance-associated protein (MRP) isoforms 1 through 6 mRNA are expressed in the human intestine and Caco-2 cells. In Caco-2 cells, the rank order for mRNA expression was MRP2 > or = MRP6 > MRP4 > or = MRP3 > MRP1 = MRP5. The functional expression of MRP-like activity was quantified as the efflux of the fluorescent probe calcein from confluent, polarized monolayers of Caco-2 cells. Calcein efflux was sensitive to temperature, energy depletion, and the MRP antagonist MK571 [3-[[3-[2-(7-chloroquinolin-2-yl)vinyl]phenyl]-(2-dimethylcarbamoylethylsulfanyl)methylsulfanyl] propionic acid]. Calcein efflux across the apical membrane of Caco-2 cells exceeded that across the basolateral by approximately 2-fold, correlating with the apical localization of MRP2 visualized by immunocytochemical staining. T84 cells do not express MRP2 and show a predominance of basolateral calcein efflux over apical efflux. MRP3 was localized by immunocytochemical staining to the basolateral membrane. MRP1 staining was not localized to either membrane domain and MRP5 staining was not detected. Thus, basolateral calcein efflux may reflect a function of MRP3 or MRP4 and 6 inferred by their basolateral localization in other tissues. Basolateral, but not apical, calcein efflux was sensitive to glutathione depletion with buthioninesulfoximine, indicating that whereas MRP2-mediated apical efflux is independent of glutathione, basolateral efflux is glutathione-dependent. Benzbromarone, probenecid, pravastatin, and diclofenac were able to inhibit both apical and basolateral calcein efflux. The apical calcein efflux in Caco-2 cells was selectively sensitive to indomethacin and propranolol, but not verapamil or erythromycin, whereas the converse was observed for basal efflux. The differential pharmacological sensitivity of apical (MRP2) and basolateral calcein efflux provides tools for dissecting MRP isoform functional roles.

Animal diets crucially affect fitness, yet many aspects of their ultimate determinants are unknown. The distribution and extent of herbivory in lizards, its evolutionary history, and ecological factors that may favour it are discussed. Most lizards are exclusively or primarily carnivorous, yet many species eat some plants and a few are almost exclusively herbivorous. Based on a literature survey of diets of over 450 lizard species, the distribution and degree of omnivory and herbivory are described. Some plants occur in the diets of slightly over half of lizard species, and plants formed 10% or more of the dietary volume of 12.1% of species, and 90% or more of the diet of 0.8% of species. The greatest percentage of omnivorous species (> 10% plant diet), over 30% in each, and highest mean percentage plant matter in the diet are in Iguanidae, Corytophanidae, Gerrhosauridae, Agamidae, Xantusiidae, and Tropiduridae. Numerous other omnivores occur in Lacertidae and Scincidae and fewer in several additional families. Herbivorous lizards (> 90% plant volume) tend to be folivorous and to possess adaptations for processing leaves, including specialized dentition for cutting or reducing leaves, elongated intestines, colic valves that slow passage of food, and intestinal flora that digest cellulose. Omnivorous lizards lacking such specializations may eat some leaves, but consume much more fruit, flowers, and seeds, plant parts that are easy to digest, likely to be very abundant seasonally, and may be highly nutritious. Some lizards eat nectar and pollen; even sap is eaten by at least one gecko. Ontogenetic increase in plant consumption and decrease in prey consumption is known, but its generality has been controversial. Such ontogeny has been demonstrated in three iguanid species, a skink, a lacertid, two tropidurids, a phrynosomatid, and two corytophanids, but it does not occur in some other species. The importance of specific foods may vary with age. Omnivory and/or herbivory have originated in many lizard families, with at least nine origins in Iguania and 23 in Scleroglossa. Origins have been rare in Gekkonoidea and Anguimorpha and common in Scincomorpha, especially in Lacertidae and Scincidae. Losses of omnivory have been much less frequent than gains. Only a few origins can account for all the herbivory in lizards. Concentrated changes tests show that there is a significant association in Lacertidae, Lacertiformes, Lacertoidea, Scincidae, and Scleroglossa between insularity and omnivory. Insular lizards may broaden their diets to compensate for limited availability of prey. Addition of other factors that reduce availability of prey, i.e. extreme aridity and cave-dwelling, to insularity, strengthened the relationship to omnivory in Lacertidae and Lacertoidea. We were unable to demonstrate a role of aridity independent of insularity, but present anecdotal evidence suggests that it may promote evolution of plant consumption. Large body size in lizards has long been associated with herbivory, and more recently, with omnivory in lacertid lizards. Using a conventional regression approach in which each species is considered to supply an independent data point, this relationship was confirmed for all lizards. Although larger species have diets with more plants, plant consumption accounts for only 9% of the variation in body length, which is not surprising given that other factors such as predation, competition, and sexual selection affect body size. The frequency of transitions body size associated with transitions to omnivory or carnivory was also examined. In Iguania, Scleroglossa, and all lizards, transitions supporting the hypothesis that omnivory favours increase in body size were significantly more frequent than non-supporting transitions. This suggests that substantial plant consumption favours evolution of larger size, probably because of the energetic considerations first presented by Pough (1973). Because actively foraging lizards move widely through the habitat to locate prey and tongue-flick to locate prey by chemical cues, we hypothesized that they may be more likely to evolve omnivory than ambush foragers, which wait motionless for prey and do not tongue-flick to locate or identify prey. The basis of this prediction is that the wider seaching of active foragers predisposes them to contact with a greater variety and quantity of plants and that chemosensory tongue-flicking used by omnivores to identify plant food might be easier to evolve in active foragers that already use pre-chemical discrimination. The prediction is supported by a significantly greater per species frequency of origins of omnivory by active foragers than by ambushers. A scenario for the progressive evolution of omnivory and herbivory from ancestrally carnivorous lizards is discussed.

OBJECTIVES: To assess and compare the effects of candesartan or lisinopril, or both, on blood pressure and urinary albumin excretion in patients with microalbuminuria, hypertension, and type 2 diabetes. DESIGN: Prospective, randomised, parallel group, double blind study with four week placebo run in period and 12 weeks' monotherapy with candesartan or lisinopril followed by 12 weeks' monotherapy or combination treatment. SETTING: Tertiary hospitals and primary care centres in four countries (37 centres). PARTICIPANTS: 199 patients aged 30-75 years. INTERVENTIONS: Candesartan 16 mg once daily, lisinopril 20 mg once daily. MAIN OUTCOME MEASURES: Blood pressure and urinary albumin:creatinine ratio. RESULTS: At 12 weeks mean (95% confidence interval) reductions in diastolic blood pressure were 9.5 mm Hg (7.7 mm Hg to 11.2 mm Hg, P<0.001) and 9.7 mm Hg (7.9 mm Hg to 11.5 mm Hg, P<0.001), respectively, and in urinary albumin:creatinine ratio were 30% (15% to 42%, P<0.001) and 46% (35% to 56%, P<0.001) for candesartan and lisinopril, respectively. At 24 weeks the mean reduction in diastolic blood pressure with combination treatment (16.3 mm Hg, 13.6 mm Hg to 18.9 mm Hg, P<0. 001) was significantly greater than that with candesartan (10.4 mm Hg, 7.7 mm Hg to 13.1 mm Hg, P<0.001) or lisinopril (mean 10.7 mm Hg, 8.0 mm Hg to 13.5 mm Hg, P<0.001). Furthermore, the reduction in urinary albumin:creatinine ratio with combination treatment (50%, 36% to 61%, P<0.001) was greater than with candesartan (24%, 0% to 43%, P=0.05) and lisinopril (39%, 20% to 54%, P<0.001). All treatments were generally well tolerated. CONCLUSION: Candesartan 16 mg once daily is as effective as lisinopril 20 mg once daily in reducing blood pressure and microalbuminuria in hypertensive patients with type 2 diabetes. Combination treatment is well tolerated and more effective in reducing blood pressure.

Background: 3-Hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) are metabolized by distinct pathways that may alter the extent of drug-drug interactions. Cerivastatin is metabolized by cytochrome P450 (CYP)3A4 and CYP2C8. Atorvastatin is metabolized solely by CYP3A4, and pravastatin metabolism is not well defined. Coadministration of higher doses of these statins with CYP3A4 inhibitors has the potential for eliciting adverse drug-drug interactions.Objective: To determine the comparative effect of itraconazole, a potent CYP3A4 inhibitor, on the pharmacokinetics of cerivastatin, atorvastatin, and pravastatin.Methods: In this single-site, randomized, three-way crossover, open-labeled study, healthy subjects (n = 18) received single doses of cerivastatin 0.8 mg, atorvastatin 20 mg, or pravastatin 40 mg without and with itraconazole 200 mg. Pharmacokinetic parameters [AUC(0-∞), AUC(0-tn), peak concentration (Cmax), time to reach Cmax(tmax), and half-life (t½)] were determined for parent statins and major metabolites.Results: Concomitant cerivastatin/itraconazole treatment produced small elevations in the cerivastatin AUC(0-∞), Cmax, and t½(27%, 25%, and 19%, respectively; P < .05 versus cerivastatin alone). Itraconazole coadministration produced similar changes in pravastatin pharmacokinetics [AUC elevated 51% (P < .05 versus pravastatin alone), 24% (Cmax), and 23% (t½), respectively]. However, itraconazole dramatically increased atorvastatin AUC (150%), Cmax(38%), and t½(30%) (P < .05). The elevation in atorvastatin AUC was significantly greater than that of cerivastatin (P < .005) or pravastatin (P < .005).Conclusion: Itraconazole markedly elevated atorvastatin plasma levels (2.5-fold) after 20 mg dosing, suggesting that concomitant itraconazole/atorvastatin therapy be carefully considered. Itraconazole produced modest elevations in the plasma levels of cerivastatin 0.8 mg or pravastatin 40 mg (1.3-fold and 1.5-fold, respectively), indicating that combination treatment with itraconazole with cerivastatin or pravastatin may be preferable. (Clin Pharmacol Ther 2000;68:391-400.)

The dose‐response relationship of oral famotidine at doses up to 10 mg was evaluated in 10 healthy male subjects to assess the extent and duration of inhibition of meal‐stimulated intragastric acid secretion. Each subject received single oral administrations of famotidine 0.5, 2.5, 5.0, and 10.0 mg and placebo in a double‐blind, randomized, crossover fashion. Intragastric pH was measured every 4 seconds for 24 hours and expressed as the mean pH for each 10‐minute interval. Standard high‐protein meals were provided 1 hour before each dose of study drug and at 3 and 9 hours postdose. The mean intragastric pH was significantly higher after famotidine doses 2.5, 5.0, and 10.0 mg than after placebo at times 2.5 to 3.0,1.8 to 3.2, and 1.7 to 4.2 hours postdose, respectively. There were no significant differences in mean pH seen between famotidine 0.5 mg versus placebo. The range of the pH means between 1.7 and 3.2 hours postdose was placebo (1.0 to 1.3), famotidine 0.5 mg (1.1 to 1.4), 2.5 mg (1.4 to 1.7), 5.0 mg (1.7 to 2.1), and 10.0 mg (2.0 to 2.3). There was a statistically significant linear dose‐response relationship between famotidine dose and intragastric pH between 1.7 and 3.8 hours and from 6.3 to 8.7 hours after ingestion.

The pharmacokinetics of ciprofloxacin, a carboxyquinolone, was studied after oral administration of the drug to seven patients with biopsy-proved cirrhosis and to seven healthy volunteers. Serum concentrations of ciprofloxacin and its three metabolites—desethylene ciprofloxacin (Ml), sulfociprofloxacin (M2), and oxociprofloxacin (M3)—were measured by an HPLC procedure. The pharmacokinetic parameters for ciprofloxacin were not significantly altered in cirrhotic patients. The elimination half-life (t1/2) and the area under the serum concentration versus time curve (AUC) were, respectively, 3.71 hours and 16.18 µg · ml-1· hr-1in the normal subjects and 3.47 hours and 18.38 µg · ml-1· hr-1in patients with cirrhosis. The formation of oxociprofloxacin was reduced by approximately one half in the cirrhotic subjects, as the Cmaxwas 0.29 µg/ml in normal subjects versus 0.14 µg/ml in cirrhotic patients and the mean AUC(0-t) was 1.54 µg · ml-1· hr-1in normal subjects versus 0.70 µg · ml-1· hr-1in cirrhotic patients. However, there appeared to be no significant difference between groups with respect to desethylene ciprofloxacin and sulfociprofloxacin. Therefore it appears from this study that no dosage adjustment is required in patients with hepatic cirrhosis.Clinical Pharmacology and Therapeutics (1989) 45, 608–616; doi:10.1038/clpt.1989.81

HISTORICAL CONSIDERATIONS The early work of Brunner1 in 1682, as reported by Ceccherelli, demonstrated that partial extirpation of the pancreas did not impair the health and digestion of the experimental animal. This salient observation has led to the development of surgical procedures which have been successful as long as the main pancreatic and biliary ducts have been left intact. However, investigations concerning the feasibility of attacking the head of the pancreas and thereby excluding the external pancreatic secretion from the intestinal tract have led to conflicting results.A historical survey of these related experimental problems shows that the conflicts date from early time.The first experimental approach to this subject was carried out by Bernard.2 He occluded the pancreatic ducts by injecting them with paraffin and observed a marked disturbance in the absorption of fat from the intestinal tract, with early death of the animal. From this observation

1. By a modification of the Tripode and Sherwin method, the pancreas can be transplanted into the stomach without danger of immediate acute pancreatitis or peritonitis. 2. The intragastric portion of the transplanted pancreas is eventually digested away. 3. The transplanted pancreas retains its external and internal function and shows no sign of atrophy. 4. Complete exclusion of the external secretion of the pancreas by stated methods produces an abnormal deposition of fat in the liver and concomitant degeneration and atrophy of the liver cells. 5. Lipid deposition and degeneration of the liver does not occur in pancreatic transplants.

The inhalation of atropine sulfate from a pressurized metered-dose inhaler was investigated in a nonrandomized four-period rising-dose study. Eight healthy, nonsmoking subjects received 1.7, 3.4, and 5.2 mg of atropine sulfate by inhalation and 1.67 mg of atropine free base (equivalent to 2 mg of atropine sulfate) by intramuscular (i.m.) injection. Serum atropine sulfate concentrations were measured over a 24-h period by gas chromatography/mass spectrometry. Mean serum concentrations increased nonproportionally as the inhaled dose increased. Mean peak concentrations were 4.9, 6.1, and 7.9 ng/ml for the inhaled doses and 8.4 ng/ml for the i.m. dose. Typical anticholinergic effects were seen after all doses.

The incidence of serious untoward reactions to meprobamate must be small in view of the widespread use of this drug. The following case is reported because it is believed to represent the first recorded instance of such a reaction to meprobamate. Furthermore, it represents a rare type of reaction to any drug. REPORT OF A CASE A 51-year-old woman was admitted on June 23, 1958, to Woman's Hospital, Philadelphia, because of a myocardial infarction. She was treated in the conventional manner with bed rest and bishydroxycoumarin (Dicumarol); in addition, her previous medication with chlorothiazide, 0.5 Gm. daily, and digoxin, 0.5 mg. daily, was continued. Pentobarbital was given nightly, but, starting on July 8, chloral hydrate was substituted. Because of continued restlessness during the day, as well as sleeplessness, therapy with meprobamate, 400 mg. given four times a day, and secobarbital and phenobarbital given at bedtime was started on July 11.

Aluminium thick film conductors offer very large cost advantages compared with noble metals and can also improve the reliability of circuits by eliminating gold-aluminium interfaces and their attendant intermetallic phenomena. To date however, it has not been possible to produce aluminium thick film conductors which are ultrasonically bondable to aluminium-silicon wire.