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In the 18th century, Albrecht von Haller (1) made the initial observation that the beat of a healthy heart is not absolutely regular. Heart rate and rhythm are governed by [...]

IMPORTANCE: Gene transfer has rarely been tested in randomized clinical trials. OBJECTIVE: To evaluate the safety and efficacy of intracoronary delivery of adenovirus 5 encoding adenylyl cyclase 6 (Ad5.hAC6) in heart failure. DESIGN, SETTING, AND PARTICIPANTS: A randomized, double-blind, placebo-controlled, phase 2 clinical trial was conducted in US medical centers (randomization occurred from July 19, 2010, to October 30, 2014). Participants 18 to 80 years with symptomatic heart failure (ischemic and nonischemic) and an ejection fraction (EF) of 40% or less were screened; 86 individuals were enrolled, and 56 were randomized. Data analysis was of the intention-to-treat population. Participants underwent exercise testing and measurement of left ventricular EF (echocardiography) and then cardiac catheterization, where left ventricular pressure development (+dP/dt) and decline (−dP/dt) were recorded. Participants were randomized (3:1 ratio) to receive 1 of 5 doses of intracoronary Ad5.hAC6 or placebo. Participants underwent a second catheterization 4 weeks later for measurement of dP/dt. Exercise testing and EF were assessed 4 and 12 weeks after randomization. INTERVENTIONS: Intracoronary administration of Ad5.hAC6 (3.2 × 109 to 1012 virus particles) or placebo. MAIN OUTCOMES AND MEASURES: Primary end points included exercise duration and EF before and 4 and 12 weeks after randomization and peak rates of +dP/dt and −dP/dt before and 4 weeks after randomization. Fourteen placebo participants were compared (intention to treat) with 24 Ad5.hAC6 participants receiving the highest 2 doses (D4 + 5). RESULTS: Fifty-six individuals were randomized and monitored for up to 1 year. Forty-two participants (75%) received Ad5.hAC6 (mean [SE] age, 63 [1] years; EF, 30% [1%]), and 14 individuals (25%) received placebo (age, 62 [1] years; EF, 30% [2%]). Exercise duration showed no significant group differences (4 weeks, P = .27; 12 weeks, P = .47, respectively). The D4 + 5 participants had increased EF at 4 weeks (+6.0 [1.7] EF units; n = 21; P < .004), but not 12 weeks (+3.0 [2.4] EF units; n = 21; P = .16). Placebo participants showed no increase in EF at 4 weeks or 12 weeks. Exercise duration showed no between-group differences (4-week change from baseline: placebo, 27 [36] seconds; D4 + 5, 44 [25] seconds; P = .27; 12-week change from baseline: placebo, 44 [28] seconds; D4 + 5, 58 [29 seconds, P = .47). AC6 gene transfer increased basal left ventricular peak −dP/dt (4-week change from baseline: placebo, +93 [51] mm Hg/s; D4 + 5, −39 [33] mm Hg/s; placebo [n = 21]; P < .03); AC6 did not increase arrhythmias. The admission rate for patients with heart failure was 9.5% (4 of 42) in the AC6 group and 28.6% (4 of 14) in the placebo group (relative risk, 0.33 [95% CI, 0.08-1.36]; P = .10). CONCLUSIONS AND RELEVANCE: AC6 gene transfer safely increased LV function beyond standard heart failure therapy, attainable with one-time administration. Larger trials are warranted. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00787059

Seed proteins fromCicer arietinum L.,C. reticulatumLadiz. andC. echinospermumDavis were extracted and separated into water soluble (albumin) and water insoluble (globulin) fractions. These were analysed using three polyacrylamide gel systems: uniform pore slab gels, gradient gels and SDS disc gels. For all three species, albumins constitute just over one-third of total protein. Minor differences in the composition of this fraction were observed. Within the globulin fraction, seven disulphide-linked polypeptides were found. Four of these resemble the major polypeptide of legumin, consisting of constant small subunit (21,000 daltons) linked to variable large subunit (46,000, 41,000, 39,000 or 36,000 daltons), forming polypeptides of 67,000 (I), 62,000 (II), 60,000 (III) and 57,000 (IV) daltons respectively. Polypeptide I was prominent in both wild species, but absent fromC. arietinum. Polypeptides II and III were equally prominent inC. arietinum andC. reticulatum. Polypeptide IV was more prominent inC. echinospermum, which was deficient in polypeptide III. Polypeptides V (45,000 daltons) and VI (43,000 daltons), apparently composed of two equal subunits, were present in trace amounts in both wild species, but well represented inC. arietinum Polypeptide VII of 45,000 daltons (31,000 + 14,000) was present in all three species.

The albumin proteins from seed ofSophora microphyllaAit. and from cotyledons ofPisum sativum L. (cv. “Greenfeast”) have been analysed electrophoretically using a range of gels of varied pore size. Plots of mobility [as 100 log10 (Rf × 100)] vs.acrylamide content of gel indicate that very few of the albumins fromS. microphylla are homologous with albumins fromP. sativum. Despite the diverse compositions of the two fractions, their amino acid analyses were surprisingly similar.

The seedcoats of legume seeds comprise a multifunctional organ with responsibilities for protection, attraction (some times), and provision of nutrients to the embryo during its development. The transmission of solutes from phloem through seedcoats, and the processing of imported metabolites by seed coat cells prior to secretion are two important aspects of the seedcoats' nutritive function considered in this review. Some of the many important questions that remain unanswered have been posed, and scope for further research indicated.

The radicle of the pea embryo (Pisum sativum L.) is known to possess a range of protein-degrading enzymes which could theoretically act in vivo to break down proteins stored in the radicle. However, most of the polypeptides of the radicle showed little evidence of net breakdown in vivo in the first 4 days from imbibition. One polypeptide, of mol. mass 13,000, was degraded almost completely between 1 and 2 days from imbibition; others, of mol. mass 84,000 and 30,000 were degraded within 4 days. The breakdown of polypeptides stored in the radicle (and plumule) is thus highly selective and closely regulated. The requirement for amino nitrogen in the growing axis is evidently met by the immediate export of amino acids from the cotyledons, rather than by massive breakdown of stored polypeptides in situ.

Objective: Nitric oxide (NO) has been proposed as a common mediator of tumor necrosis factor-α (TNFα)-induced vasodilation and myocardial dysfunction. Accordingly, we performed an extensive assessment of the influence of NO synthase inhibition on left ventricle (LV) and circulatory performance in conscious dogs at steady state and after establishment of TNFα mediated myodepression. Methods: Autonomically blocked, chronically instrumented dogs were studied at steady state and 6 h after initiation of a 1-h rhTNFα infusion (40 μg/kg). Ventricular performance was evaluated using the pressure–volume framework. Dogs were then treated with either NG-nitro-l-arginine methylester (l-NAME, 40 mg/kg bolus) or angiotensin II (250–500 ng/kg). Results: l-NAME, under control conditions or following recombinant human (rh)TNFα-induced ventricular dysfunction, produced marked increases in afterload with attendant increases in LV pressure, volume, and prolonged isovolumic relaxation without adversely influencing coronary blood flow. Regardless of whether the dogs received rhTNFα, l-NAME did not affect the slopes of the end-systolic pressure–volume and stroke-work (SW)-end-diastolic volume (EDV) relations (force-based measure of contractility), whereas the slope of the dP/dtmax–EDV relation, a velocity dependent parameter of LV systolic function, declined. Overall ventricular performance, as seen by the circulation, was reduced by l-NAME in control as well as rhTNFα-treated dogs, evidenced by rightward shifts of the SW–EDV and dP/dtmax–EDV relations. Similar findings were observed in the separate cohorts of dogs, at steady state and 6 h after rhTNFα, following angiotensin II at matched systolic pressure. Conclusions: Systemic NO synthase inhibition with l-NAME does not acutely reverse rhTNFα-induced myocardial dysfunction. The detrimental influence of l-NAME on LV size, relaxation, and velocity-based measures of contractility is likely attributable to its effects on increasing afterload.

Tumor necrosis factor-α (TNFα) plays a role in the pathophysiology of myocardial depression observed in septic shock and myocarditis. Limited responsiveness to inotropic therapy in these pathological states may be related to cytokine mediated disruption of adrenergic signal transduction. In cultured myocytes, TNFα reversibly inhibits isoproterenol mediated increases in both contractility and intracellular cAMP accumulation via interference with β-adrenergic receptor coupling to adenylate cyclase. Whether TNFα alters myocardial responsiveness to exogenous υβ-adrenergic stimulation in the intact animal has yet to be determined. Accordingly, we evaluated the effects of dobutamine (Dob) in 9 conscious dogs, chronically instrumented with 3 sets of diameter gauges and LV manometers, treated with a 1 hour infusion of TNFα (40μg/kg). Mw, the slope of the relation between stroke-work and enddiastolic volume, was determined before and after brief infusions of Dob (4/μg/kg/min) at multiple times after TNFα. TNFα produced a reduction in baseline contractile performance beginning 4 hours and extending to 25 hours after initiation of infusion. The percentage increase of Mw induced by Dob dropped from 34±7% pre-TN Fα to a nadir of 15 ± 5% 3 hours post-TNFα, an effect which persisted but then dissipated. Similar results were found when end-systolic elastance and dP/dtmaxwere evaluated. We concludethat TNFα impairs myocardial responsiveness to fi-adrenergic stimulation in the intact animal, an effect separate from its primary myocardial depressant properties.