Exploring the potentials of underutilized grain amaranth (Amaranthus spp.) along the value chain for food and nutrition security: A review

The burden of malnutrition in Africa calls for deeper exploration of underutilized species which are rich in nutrients and have the potential to reduce food and nutrition insecurity. The common staple crops are not able to meet daily requirements for both macro- and micro-nutrients. In order to lessen this burden; protein, calorie and micronutrient deficiencies must be properly addressed for optimal growth and development to be attained. African indigenous underutilized vegetables can play a significant role in the food security of vulnerable groups like under-five children and women in both urban and rural settings. The potential of grain amaranth in meeting the nutrition needs of humans has remained a subject of interest in scientific research. Amaranth is considered one of the most commonly produced and consumed indigenous vegetables on the African continent with high nutritional potentials but yet to be fully exploited. This review therefore aims at discussing the current knowledge of the inherent potentials of grain amaranths, its current application in the food industry and proposes a framework for actions and partnerships required to scale up and improve amaranth value chain.

Pseudorheumatoid nodule: a variant of granuloma annulare?

We present an adult woman with subcutaneous nodules without any signs or symptoms of rheumatoid arthritis. These nodules are believed to be pseudorheumatoid nodules, which are considered a deep form of granuloma annulare. This case is unique because these are typically found in children and have rarely been reported in adults. These nodules are typically asymptomatic and do not require treatment. However, attempts have been made to treat them with intralesional corticosteroids, cryotherapy, or excision. Owing to the fact that this is considered a deep form of granuloma annulare, they are sometimes treated similarly with a combination of monthly rifampin, ofloxacin, and minocycline.

Feeding practices of pre-school children and associated factors in Kathmandu, Nepal

BACKGROUND

In developing countries such as Nepal, many children aged below 3 years do not grow at a sufficiently high rate and are vulnerable to micronutrient deficiencies (e.g. vitamin A). Challenges to child nutrition can result from poverty, unhealthy traditional practices, inadequate caring and feeding practices. The present study aimed to assess the feeding practices of pre-school children and their associated factors.

METHODS

A cross-sectional study was carried out in pre-schools located in Kathmandu district between February and March 2018. Three levels in terms of price range (lower, medium and higher level) of pre-schools were selected to reach the mothers of children aged ≤3 years. A structured questionnaire was administered to 145 mothers. Descriptive analyses were conducted to observe the characteristics of the population. Multinomial logistic regression analyses were performed to identify the association for the factors of mothers' perception of their current feeding practices.

RESULTS

We found that dal-bhat/jaulo was a common complementary food irrespective of socio-economic background. Interestingly, mothers who had received a higher education were significantly less likely to change their feeding practices (odds ratio = 0.118, confidence interval = 0.01-0.94). The mothers that fed a higher quantity porridge to their children showed a high willingness to change the feeding practices.

CONCLUSIONS

Poor feeding practices are still an important public health problem in Nepal and were observed to be associated with low socio-economic status, unawareness and a lack of knowledge towards dietary diversity combined with strong beliefs related to social forces and cultures.

Evaluation of a pharmacotherapy context-learning programme for preclinical medical students

AIM

To evaluate a context-learning pharmacotherapy programme for approximately 750 2nd, 3rd and 4th year preclinical medical students with respect to mastering cognitive pharmacotherapeutic skills, i.e. choosing a (drug) treatment and determining patient information.

METHODS

The context-learning pharmacotherapy programme consists of weekly organized role play sessions in the form of consulting hours. Fourth year students sit for a therapeutic Objective Structured Clinical Examination (OSCE) in the form of consulting hours at the outpatient clinic. Sixty-one 2nd, 74 3rd and 49 4th year medical students who attended the role play sessions and the OSCE were randomly selected. Their performances were assessed by clinical examiners and clinical experts and compared with a reference group of 6th year graduated students. Additionally, the scores of a questionnaire on study load and appreciation were collected.

RESULTS

The level of the pharmacotherapeutic skills of the 4th year students who followed the pharmacotherapy context-learning programme was not far below that of 6th year graduates who had finished their clinical clerkships, but had not followed the pharmacotherapy programme. The time spent on the programme was about 1% of the total study load per year. The students appreciated the role play sessions and OSCE by around 80% and 99% of the maximum possible scores.

CONCLUSIONS

Preclinical pharmacotherapy context learning has a modest but positive effect on learning cognitive pharmacotherapeutic skills, i.e. choosing a drug treatment and determining patient information. This effect has been obtained with role play sessions, a suboptimal form of context learning, with a minimal study load and a high appreciation by students.

The influence of gallium and other metal ions on the uptake of non-transferrin-bound iron by rat hepatocytes

BACKGROUND

Under conditions of iron overload non-transferrin-bound iron (NTBI) occurs in the circulation and is mainly cleared by the liver. Beside iron, gallium and aluminum enhance accumulation of NTBI. We try to characterize the mechanism and metal-mediated regulation of NTBI uptake using cultivated primary rat hepatocytes.

METHODS

Hepatocytes from rat liver were incubated with 0.1 mg/ml transferrin (as control), with ferric ammonium citrate or other di- and trivalent metal salts and the uptake of (55)Fe-labeled Fe-diethylene triammine pentaacetate was measured.

RESULTS

Uptake rates for iron increased from 0.3 to 2.1 pmol/mg protein per min in cells preincubated for 5 hours with 300 microM ferric ammonium citrate, to 1.7 pmol/mg protein per min with gallium and to 1.2 pmol/mg protein per min with aluminum. Maximal stimulation was obtained with 300 microM iron and 600 microM gallium. Preincubation with divalent metals was ineffective. NTBI uptake was specific for iron, partly inhibited by gallium citrate, diferric transferrin and completely inhibited by apotransferrin in control and gallium-treated cells. In iron-loaded cells, inhibition of NTBI uptake by diferric transferrin completely disappeared within 2 hours.

CONCLUSIONS

These experiments show that hepatocytes do respond to the presence of trivalent metals by an increased transport capacity to sequester these ions. The metals seem to have at least partly different mechanisms of transport stimulation.

Recombinant human erythropoietin: effects on frataxin expression in vitro

BACKGROUND

Friedreich's ataxia (FRDA) is a neurodegenerative disorder caused by decreased expression of the protein frataxin, recently described to be an iron chaperone for the assembly of iron-sulphur clusters in the mitochondria, causing iron accumulation in mitochondria, oxidative stress and cell damage. Searching for compounds that could possibly influence frataxin expression, we found that the cytokine recombinant human erythropoietin (rhuEPO) significantly increases frataxin expression by a still unknown mechanism.

MATERIALS AND METHODS

Isolated lymphocytes from FRDA patients, isolated human cardiac cells (fibroblasts and myocytes) from patients undergoing heart transplantation and P19 mouse cells (neuronal typ), were incubated with different concentrations of rhuEPO, and immunoblot was carried out for the detection of frataxin.

RESULTS

We show for the first time that the cytokine recombinant human erythropoietin (rhuEPO) can, additionally to its reported neuro- and cardioprotective properties, increase frataxin expression in vitro. We show that rhuEPO significantly increases frataxin expression in primary lymphocytes from patients with Friedreich's ataxia. Further we show that rhuEPO can also increase frataxin expression in many other cell types; among them the most affected cell types in FRDA such as neurones and cardiac cells.

CONCLUSIONS

Our results provide a scientific basis for further studies examining the effectiveness of this agent for the treatment of FRDA patients.

Prediction of outcome by neurohumoral activation, the six-minute walk test and the Minnesota Living with Heart Failure Questionnaire in an outpatient cohort with congestive heart failure

AIMS

To compare the precursor of atrial and brain natriuretic peptide (N-ANP, N-BNP), brain natriuretic peptide (BNP), big endothelin-1, the 6-min walk test and the Minnesota Living with Heart Failure Questionnaire (LHFQ) with regard to short-term outcome in an ambulatory heart failure population.

METHODS AND RESULTS

Ninety-six individuals (left ventricular ejection fraction of 26+/-10%) were included in the study. Within 1 day blood samples of N-ANP, N-BNP, BNP and big endothelin-1 were obtained, and the 6-min walk test and LHFQ were measured. The predictive power of these variables - including renin-angiotensin system antagonist therapy - in respect of 1-year event-free survival were calculated with a Cox regression analysis. All investigated variables had the power to predict outcome in a univariate analysis. Multivariate analysis revealed that N-ANP (chi-square=58 P<0.0001), BNP (chi-square=8 P<0.01), the LHFQ (chi-square=6 P<0.02) and the renin-angiotensin system antagonist (chi-square=4 P<0.05), are independent predictors.

CONCLUSION

We conclude that, in an open clinical cohort of patients with large differences in the progression of the disease, N-ANP, BNP and LHFQ are the most reliable predictors of worsening heart failure in the short term. However, the dosage of the ACE inhibitor influenced short-term survival in this population.

Long-term effect of atenolol on ejection fraction, symptoms, and exercise variables in patients with advanced left ventricular dysfunction

AIMS

We recently reported a beneficial clinical effect of atenolol, a beta(1) selective adrenergic antagonist, in 100 ambulatory heart failure patients with low left ventricular ejection fraction (LVEF, <or=25%) who were receiving background therapy with 40 mg/day enalapril. In this sub-study, we investigated the effects of atenolol vs placebo on LVEF, New York Heart Association (NYHA) class, workload, and peak oxygen consumption (Vo(2)).

METHODS AND RESULTS

We included 43 patients (23 receiving atenolol, 20 receiving placebo) who had similar entry characteristics. We evaluated LVEF once a year and evaluated workload, pVO(2), and NYHA class before and after 6, 12, and 24 months. Repeated measures of analysis of variance were used for comparison of serial measurements. After 2 years, both atenolol (18% +/- 5% vs 36% +/- 18%, p < 0.05) and placebo (18% +/- 5% vs 23% +/- 5%, p < 0.05) increased LVEF, with a more pronounced effect of atenolol (p = 0.02), which also changed NYHA class distribution more favorably over time (p < 0.05). Workload and peak Vo(2) increased after atenolol (110 +/- 47 vs 140 +/- 48 watts, p < 0.05, and 18 +/- 5 vs 21 +/- 5 ml/kg/min, p < 0.05) but not after placebo (100 +/- 35 vs 110 +/- 38 watts, p < 0.05, between groups and 17 +/- 4 vs 19 +/- 7 ml/kg/min, not significant, between groups).

CONCLUSIONS

In patients with advanced heart failure who tolerate long-term atenolol vs placebo treatment added to high-dose enalapril for 2 years without cardiac events, systolic left ventricular function is markedly improved. These patients experience greater relief of symptoms and increased exercise tolerance.

Clinical validation of an automated boundary tracking algorithm on cardiac MR images

The goal of this research was to develop an automated algorithm for tracking the borders of the left ventricle (LV) in a cine-MRI gradient-echo temporal data set. The algorithm was validated on four patient populations: healthy volunteers and patients with dilated cardiomyopathy (DCM), left ventricular hypertrophy (LVH), or left ventricular aneurysm (LVA). A full tomographic set (approximately 11 slices/case) of short-axis images through systole was obtained for each patient. Initial endocardial and epicardial contours for the end-diastolic (ED) and end-systolic (ES) frames were manually traced on the computer by an experienced radiologist. The ED tracings were used as the starting point for the algorithm. The borders were tracked through each phase of the temporal data set, until the ES frame was reached (approximately 7 phases/slice). Peak gradients along equally spaced chords calculated perpendicular to a centerline determined midway between the endocardial and epicardial borders were used for border detection. This approach was tested by comparing the LV epicardial and endocardial volumes calculated at ES to those based on the manual tracings. The results of the algorithm compared favorably with both the endocardial (r2 = 0.72 - 0.98) and epicardial (r2 = 0.96 - 0.99) volumes of the tracer.

Prognostic evaluation of neurohumoral plasma levels before and during beta-blocker therapy in advanced left ventricular dysfunction

OBJECTIVES

The study assessed the relative predictive potency of neurohumoral factors in patients with advanced left ventricular (LV) dysfunction during neurohumoral blocking therapy.

BACKGROUND

The course of heart failure is characterized by progressive LV deterioration associated with an increase in cardiac (natriuretic peptides) and predominantly extracardiac (norepinephrine, big endothelin [big ET]) hormone plasma levels.

METHODS

Plasma hormones were measured at baseline and months 3, 6, 12 and 24 in 91 patients with heart failure (left ventricular ejection fraction [LVEF] <25%) receiving 40 mg enalapril/day and double-blind atenolol (50 to 100 mg/day) or placebo. After the double-blind study phase, patients were followed up to four years. Stepwise multivariate regression analyses were performed with 10 variables (age, etiology, LVEF, symptom class, atenolol/placebo, norepinephrine, big ET, log aminoterminal atrial natriuretic peptide, log aminoterminal B-type natriuretic peptide [N-BNP] and log B-type natriuretic peptide [BNP]). During the study, the last values prior to patient death were used, and in survivors the last hormone level, New York Heart Association class and LVEF at month 24 were used.

RESULTS

Thirty-one patients died from a cardiovascular cause during follow-up. At baseline, log BNP plasma level (x2 = 13.9, p = 0.0002), treatment allocation (x2 = 9.5, p = 0.002) and LVEF (x2 = 5.6, p = 0.017) were independently related to mortality. During the study, log BNP plasma level (x2 = 21.3, p = 0.0001) remained the strongest predictive marker, with LVEF (x2 = 11.2, p = 0.0008) log N-BNP plasma level (x2 = 8.9, p = 0.0027) and treatment allocation (x2 = 6.4, p = 0.0109) providing additional independent information.

CONCLUSIONS

In patients with advanced LV dysfunction receiving high-dose angiotensin-converting enzyme inhibitors and beta-blocker therapy BNP and N-BNP plasma levels are both independently related to mortality. This observation highlights the importance of these hormones and implies that they will likely emerge as a very useful blood test for detection of the progression of heart failure, even in the face of neurohumoral blocking therapy.

Improvement of thigh muscles by neuromuscular electrical stimulation in patients with refractory heart failure: a single-blind, randomized, controlled trial

OBJECTIVE

To determine the impact of an 8-wk neuromuscular stimulation program of thigh muscles on strength and cross-sectional area in patients with refractory heart failure listed for transplantation.

DESIGN

Forty-two patients with a stable disease course were assigned randomly to a stimulation group (SG) or a control group (CG). The stimulation protocol consisted of biphasic symmetric impulses with a frequency of 50 Hz and an on/off regime of 2/6 sec.

RESULTS

Primary outcome measures were isometric and isokinetic thigh muscle strength and muscle cross-sectional area. Our results showed an increase of muscle strength by mean 22.7 for knee extensor and by 35.4 for knee flexor muscles. The CG remained unchanged or decreased by -8.4 in extensor strength. Cross-sectional area increased in the SG by 15.5 and in the CG by 1.7.

CONCLUSIONS

Activities of daily living as well as quality of life increased in the SG but not in the CG. Subscales of the SF-36 increased significantly in the SG, especially concerning physical functioning by +7.5 (1.3-30.0), emotional role by +33.3 (0-66.6), and social functioning by +18.8 (0-46.9), all P < 0.05. Neither a change nor a decrease was observed in the CG. Neuromuscular electrical stimulation of thigh muscles in patients with refractory heart failure is effective in increasing muscle strength and bulk and positively affects the perception of quality of life and activities of daily living.

Regional heterogeneity of function in nonischemic dilated cardiomyopathy

OBJECTIVE

To quantify regional three-dimensional (3D) motion and myocardial strain using magnetic resonance (MR) tissue tagging in patients with non-ischemic dilated cardiomyopathy (DCM).

METHODS

MR grid tagged images were obtained in multiple short- and long-axis planes in thirteen DCM patients. Regional 3D displacements and strains were calculated with the aid of a finite element model. Five of the patients were also imaged after LV volume reduction by partial left ventriculectomy (PLV), combined with mitral and tricuspid valve repair.

RESULTS

DCM patients showed consistent, marked regional heterogeneity. Systolic lengthening occurred in the septum in both circumferential (%S(C) -5+/-7%) and longitudinal (%S(L) -2+/-5%) shortening components (negative values indicating lengthening). In contrast, the lateral wall showed relatively normal systolic shortening (%S(C) 12+/-6% and %S(L) 6+/-5%, P<0.001 lateral vs. septal walls). A geometric estimate of regional stress was correlated with shortening on a regional basis, but could not account for the differences in shortening between regions. In the five patients imaged post-PLV, septal function recovered (%S(C) 9+/-5%,%S(L) 6+/-5%, P<0.02 pre vs. post) with normalization of wall stress, whereas lateral wall shortening was reduced (%S(C) 7+/-6%,%S(L) 3+/-3%, P<0.02 pre vs. post) around the site of surgical resection.

CONCLUSIONS

A consistent pattern of regional heterogeneity of myocardial strain was seen in all patients. Reduced function may be related to increased wall stress, since recovery of septal function is possible after PLV. However, simple geometric stress determinants are not sufficient to explain the functional heterogeneity observed.

Effect of beta 1 blockade with atenolol on progression of heart failure in patients pretreated with high-dose enalapril

BACKGROUND

The survival benefit of beta-blocker treatment in patients with heart failure has been established in recent trials. Yet, the impact of beta-blockers added on high dose angiotensin converting enzyme inhibitors has not been reported.

AIMS

To investigate the effect of atenolol, a hydrophilic, selective beta1-adrenergic antagonist, added on enalapril 40 mg/day in patients with advanced left ventricular dysfunction in a double-blind placebo-controlled trial.

METHODS

One hundred and nineteen patients with class II or III heart failure, left ventricular ejection fraction < or = 25% and treatment with 40 mg enalapril daily were given an initial challenge dose of atenolol 12. 5 mg. One hundred patients (54 with idiopathic, 28 with ischemic, 18 with other dilated cardiomyopathy) tolerated challenge and were randomized to atenolol (maintenance dose 89+/-11 mg/day, range 50-100 mg/day) or placebo. The primary endpoint was combined worsening heart failure or death within 2 years, the secondary endpoint was hospitalization for cardiac events.

RESULTS

After 395+/-266 days interim analysis revealed a significant difference between the atenolol and placebo group (log rank P<0.01) and the trial was concluded. Twenty-seven patients had developed worsening heart failure (8 in the atenolol group vs. 19 in the placebo group) and 13 patients had died (5 in the atenolol vs. 8 in the placebo group). Overall there were 23 hospitalizations for cardiac events (6 in the atenolol group vs. 21 in the placebo group, P=0.07); 17 hospitalizations were due to worsening heart failure (5 in the atenolol group, 12 in the placebo-group, P=0.05) and 10 due to arrhythmias (1 in the atenolol group vs. 9 in the placebo group, P<0.01)

CONCLUSIONS

The data suggest that in patients with advanced left ventricular dysfunction, beta-blockers can provide substantial benefits supplementary to that already achieved with high dose enalapril treatment.

Estimation of current leakage in left and right ventricular conductance volumetry using a dynamic finite element model

Leakage of electric current through cardiac structures surrounding the ventricle is a primary source of error during ventricular volume measurements using a conductance catheter. This error can be represented as a leakage volume, VL. VL is generally estimated by a saline-bolus method, and is assumed constant throughout the cardiac cycle. However, dynamic changes in ventricular volume and cardiac wall thickness could change VL. To estimate VL, a dynamic finite element model of the heart was developed based on MR images. Conductance measurements were simulated using a modeled conductance catheter, and true VL was calculated. VL varied from 22.7 ml (end-systole) to 26.4 ml (end-diastole) in the left ventricle and from 19.9 ml (end-systole) to 26.9 ml (end-diastole) in the right ventricle. The saline-bolus method underestimated VL in both the left (VL = 19.4 ml) and the right (VL = 4.1 ml) ventricular volume measurements. VL increased linearly with the ratio of blood to tissue resistivity, and changed minimally with catheter position. These results indicate that VL has to be estimated dynamically throughout the cardiac cycle to obtain accurate cardiac volume measurements. The results also show that the saline bolus method does not estimate current leakage accurately, especially in the right ventricular volume measurement.

Response of right ventricular function to prostaglandin E1 infusion predicts outcome for severe chronic heart failure patients awaiting urgent transplantation

BACKGROUND

Selection of patients for urgent heart transplantation who have end-stage heart failure requires objective criteria to distinguish between subjects who may deteriorate clinically and those who can be stabilized. This population appears to differ in terms of right ventricular function, and right ventricular changes in loading may provide prognostic information. To investigate predictive parameters of patients admitted for urgent heart transplantation, we prospectively studied the mechanical performance of the right ventricle during acute afterload reduction.

PATIENTS AND METHODS

We studied 68 heart failure patients hospitalized for bridge-to-transplant. The patients underwent right heart catherization at baseline and during prostaglandin E1 infusion. We stratified patients according to clinical outcome: Group A comprised patients who could be weaned from bridging therapy or who were electively transplanted after at least 90 days, and Group B comprised patients who died or who remained unstable and required transplant under urgent conditions.

RESULTS

Right ventricular hemodynamics at baseline were comparable in both groups. However, during maximal vasodilatation, with prostaglandin E1 infusion, the right ventricular end-diastolic volume index (EDVI) was significantly reduced in Group A, (-23 ml/m(2) (p < 0.01) vs +12 ml/m(2) (p = n.s. DeltaEDVI in Group B. Reduction of EDVI by less than 10% during prostaglandin E1 infusion has a sensitivity of 89% and a specificity of 70% for clinical deterioration.

CONCLUSIONS

The response of right ventricular volumes to prostaglandin E1 may predict the outcome of patients with severe congestive heart failure listed for urgent heart transplantation.

Quality of life in patients with chronic heart failure: a randomized controlled trial of changes induced by a regular exercise program

The aim of this study was to evaluate the impact of a three-month exercise program on the perception of quality of life in patients with severe chronic heart failure. In a randomized controlled setting, 27 patients with a left ventricular ejection fraction of 18.1 +/- 8.0% were entered into the study. The training group performed aerobic exercises for three hours/week while the control group continued their usual activities of daily living. Quality of life was measured using the German version of the MOS SF-36. Two patients required a change in their drug regimen and were therefore withdrawn from the study. Twenty-five patients completed the study. In the exercise group the perception of quality of life improved significantly in the domains of vitality (p = 0.0001), physical role fulfillment (p = 0.001), physical (p = 0.02) and social (p = 0.0002) functioning. Exercise was effective in increasing peak oxygen uptake and exercise time (p < 0.01). Only weak correlations were registered between parameters of physical performance and quality of life domains. The results of the study indicate that aerobic exercise can improve the perception of quality of life in patients with severe chronic heart failure.

Moderate-intensity exercise training with elements of step aerobics in patients with severe chronic heart failure

OBJECTIVE

To evaluate whether a specific program of moderate-intensity step aerobics training may be sufficient to improve the exercise tolerance of patients with severe chronic heart failure.

PATIENTS

Twenty-six patients (22 men, 4 women; mean +/- SD age, 54 +/- 9yrs) with a history of severe chronic heart failure (left ventricular ejection fraction of 18% +/- 8%).

STUDY DESIGN

Prospective, randomized, controlled trial. Patients were randomized into exercise and control groups. All patients underwent a clinical examination and a ramp pattern cycle exercise test before and after the observation period. The exercise group underwent a moderate-intensity (50% of peak oxygen uptake) 12-week training program, progressing to 100 minutes per week of step aerobics and 50 minutes per week of cycling. The control group did not perform a training program.

MAIN OUTCOME MEASURES

Peak oxygen uptake, peak workload, percent of predicted power ability.

RESULTS

Significant increases in peak oxygen uptake (15 +/- 3.4 to 18.5 +/- 2.9mL/kg/min; p = .001), peak workload (77 +/- 26 to 99 +/- 31 watts; p = .000), and percent of predicted power ability (43% +/- 10% to 56% +/- 13%; p = .000) were observed in the exercise group. No significant changes in baseline parameters occurred in the control group. There were no critical changes in heart rate or blood pressure in either group.

CONCLUSION

Moderate-intensity step aerobics training significantly increases peak oxygen uptake and peak workloads in patients with severe chronic heart failure.

[Skeletal muscle strength following orthotopic heart transplantation]

AIM OF THE STUDY

Strength measurement of thigh muscles of patients after orthotopic heart transplantation (HTX) with a sedentary lifestyle, entering a cardiac rehabilitation program.

DESIGN

Cross-sectional study; values are compared to patients with chronic heart failure (CHF) and healthy controls.

METHODS

Isometric and isokinetic peak torque of knee extensor and flexor muscles measured on a Cybex 6000. Twenty minutes' muscle fatigue test of knee extensor muscles. Test of motor tasks of daily living.

RESULTS

HTX group: n = 18, age 59 +/- 7 years, body mass index (BMI) 29 +/- 5, months after HTX 46 +/- 36 months; CHI group: n = 24, age 55 +/- 8 years, BMI 25 +/- 4, months after CHF 19 +/- 16 months; control group: n = 10, age 55 +/- 6 years, BMI 26 +/- 5. The HTX group differed significantly (p < 0.05) from the CHI group. Peak torque of knee extensor muscles: HTX: 120.3 +/- 8.4; CHI: 127.8 +/- 8.0 Nm; controls: 158.3 +/- 5.5 (ANOVA p < 0.05); peak torque of knee flexor muscles: HTX 65.6 +/- 5.9 Nm; CHI 70.1 +/- 6.2 Nm; controls 84.4 +/- 3.1 Nm(ANOVA p < 0.01). Peak torque of knee extensor muscles related to body weight: HTX: 137.4 +/- 10.0 Nm%, CHI: 162.6 +/- 9.3 Nm%, control group 202.8 +/- 5.7 Nm% (ANOVA p < 0.01). Muscle fatigue test of knee extensor muscles: isometric maximal strength (maximal voluntary contraction, MCV; HTX vs. CHI): 331.6 +/- 14.7 N vs. 335.5 +/- 18.6 N (n.s.), MVC after 5 minutes 296.3 +/- 15.7 N vs. 288.4 +/- 16.7 N; MVC after 10 minutes: 283.5 +/- 15.7 N vs. 282.5 +/- 17.7 N; MVC after 15 minutes 275.7 +/- 13.7 N vs. 280.6 +/- 21.6 N. No significant differences between groups were observed. All values were significantly lower than those of healthy controls (406.2 N; 385.9 N; 373.7 N and 369.6 N). There was a significant decline in MVC after 5 minutes compared to initial values (p < 0.01), in both patients groups but not in the control group. No further decline in MVC was observed beyond the 5th minute of the fatigue test (p > 0.05).

CONCLUSION

Peak torque related to body weight and muscle endurance of knee extensor muscles of sedentary patients after orthotopic HTX do not significantly differ from those of comparable patients with CHF but do differ from those of healthy controls. Specific training of muscle strength is needed for patients even several years after orthotopic heart transplantation.

Strength improvement of knee extensor muscles in patients with chronic heart failure by neuromuscular electrical stimulation

Patients with severe chronic heart failure (CHF) suffer from marked weakness of skeletal muscles. Neuromuscular electrical stimulation (NMES) proved to be an alternative to active strength training. The objective of this study was to test the feasibility and effectiveness of NMES in patients with chronic heart failure. Seven patients (56.0 +/- 5.0 years, CHF for 20 +/- 4 months, left ventricular ejection fraction 20.1 +/- 10.0%) finished an 8 week course of NMES of the knee extensor muscles. The stimulator delivered biphasic, symmetric, constant voltage impulses of 0.7 ms pulse width with a frequency of 50 Hz, 2 s on and 6 s off. No adverse effects occurred. After the stimulation period, the isokinetic peak torque of the knee extensor muscles increased by 13% from 101.0 +/- 8.7 Nm to 113.5 +/- 7.2 Nm (p = 0.004). The maximal isometric strength increased by 20% from 294.3 +/- 19.6 N to 354.14 +/- 15.7 N (p = 0.04). This increased muscle strength could be maintained in a 20 min fatigue test indicating decreased muscle fatigue. These results demonstrate that NMES of skeletal muscles in patients with severe chronic heart failure is a promising method for strength training in this group of patients.

Bridging to heart transplantation: prostaglandin E1 versus prostacyclin versus dobutamine

BACKGROUND

Prostaglandin E1 (PGE1) and prostacyclin have potent pulmonary and systemic vasodilating properties. This prospective, randomized trial compared PGE1 vs prostacyclin vs. low-dose dobutamine in patients with low-output heart failure awaiting heart transplantation (HTx) who were refractory to oral treatment.

METHODS

Patients in advanced heart failure in New York Heart Association (NYHA) Class IV, with a cardiac index < or = 2.5 L/minute/m2 and a pulmonary capillary wedge pressure > or = 20 mmHg, who were listed for HTx were studied. In an inpatient study phase of 12 hours duration, therapy was aimed to increase cardiac output by 20% or more, when compared to baseline values, and to achieve a reduction of pulmonary vascular resistance below 550 dyn.s/cm-5m-2. During a long-term outpatient phase, the drugs were continuously infused to bridge these patients to HTx using three combined negative endpoints (worsening heart failure, serious adverse events, death) for analysis.

RESULTS

Sixty-eight patients were enrolled, 30 patients on PGE1, 8 patients on prostacyclin, and 30 patients on dobutamine. During the inpatient study phase, maximum doses were 22 +/- 1.8 ng/kg/minute for PGE1, 7 +/- 1 ng/kg/minute for prostacyclin and 5 +/- 0.4 micrograms/kg/minute for dobutamine. During the inpatient study phase 21 patients failed, 4/30 (13%) patients on PGE1, 4/8 patients on prostacyclin (50%), and 13/30 (43%) on dobutamine (p < 0.05). Long-term continuous intravenous drug infusion in outpatients was begun in 26 patients on PGE1, in 4 patients on prostacyclin, and in 17 patients on dobutamine. Infusion therapy lasted for 88 +/- 14 days in the PGE1 group with 31 +/- 22 days in the prostacyclin group, and 30 +/- 8 days in the dobutamine group (NS). During the outpatient phase 23 patients reached a negative endpoint with 16 patients developing worsening heart failure, 5 severe adverse events and 2 deaths. Seven out of 26 (27%) failed on PGE1, 4/4 (100%) failed on prostacyclin, and 12/17 (71%) failed on dobutamine (p < 0.05, log rank test). Because prostacyclin treatment was ineffective in the first 8 patients, this trial arm was stopped prematurely.

CONCLUSIONS

The findings from this prospective open pilot trial suggest that continuous PGE1 infusions at individualized dosages can be useful in certain patients as a pharmacologic bridging procedure with reduced risk to develop worsening heart failure before HTx compared to prostacyclin and dobutamine. Further comparative studies are warranted to investigate the effects of PGE1 among other bridging agents.

Benefit of 6 months long-term physical training in polymyositis/dermatomyositis patients

OBJECTIVE

The benefit of long-term physical training in patients with chronic polymyositis or dermatomyositis (PM/DM) was studied prospectively.

METHODS

Eight patients with chronic PM/DM participated in a training programme for 6 months. A group of five PM/DM patients without any physical training was observed for control purposes.

RESULTS

While there was no significant change in serum creatine phosphokinase (CPK) levels, the 'activities of daily living (ADL)' score improved significantly (P < 0.03), peak isometric torque (PIT) generated by muscle groups in the lower extremities rose significantly (P < 0.03) and there was a statistically highly significant increase in peak oxygen uptake (VO2max) relative to body weight (P < 0.02) due to the long-term training. The patients improved their aerobic capacity by 28%, which is clinically significant. In the untrained patients, no improvement in these target parameters was observed.

CONCLUSION

In clinically stable DM/PM patients, long-term physical training can safely be performed and is recommended as part of a comprehensive rehabilitation management, particularly in view of the cardiopulmonary risk in these patients.

Value of cardiopulmonary exercise testing and big endothelin plasma levels to predict short-term prognosis of patients with chronic heart failure

OBJECTIVES

We tested the hypothesis that, in patients with stable heart failure, measuring big endothelin-1 (ET-1) plasma level at rest predicts short-term prognosis better than peak oxygen consumption (VO2max) at exercise.

BACKGROUND

Cardiopulmonary exercise testing and evaluation of neurohumoral plasma factors are established tools to estimate survival in patients with heart failure. No data, however, exist comparing the prognostic value of both marker categories simultaneously.

METHODS

Two hundred twenty-six heart failure patients were studied in regard to a combined end point of death and prioritization for urgent cardiac transplantation within 1 year follow-up.

RESULTS

During the study period 149 patients were without cardiac events (group A), 69 patients died or were urgently transplanted (group B) and 8 patients were alive after a nonurgent heart transplant operation. Norepinephrine (p < 0.0001), atrial natriuretic peptide (p < 0.001), big endothelin plasma levels (p < 0.0001 as well as workload, VO2max and achieved percentage of predicted peak oxygen consumption (pVO2max) (all p < 0.0001) differed significantly between groups A and B. In multivariate stepwise regression analysis, however, only big ET-1 plasma concentration (chi2=74.4, p < 0.0001), New York Heart Association function class (chi2=33.9, p < 0.0001), maximal workload (chi2=7.2, p < 0.01, and plasma atrial natriuretic peptide (ANP) concentration (chi2=4.6, p < 0.05) were independently related to outcome. Peak oxygen consumption or pVO2max did not reach statistical significance in this model. Event-free survival rates were significantly lower in patients with a big ET-1 level of 4.3 fmol/ml or more than with lower big ET-1 levels (p < 0.0001).

CONCLUSION

We conclude that in patients with chronic heart failure who are stable on oral therapy measuring big ET-1 and ANP plasma levels may be a valuable noninvasive adjunct to improve the prognostic accuracy of detecting high risk patients compared with exercise testing alone.

Rapid reversal of angiotensin I-induced contractions in rat carotid arteries after acute and chronic treatment with the angiotensin-converting enzyme inhibitor, 3-[(5-amino-1-carboxy-1S-pentyl)amino]2,3,4,5-tetrahydro-2-oxo- 3S-1H-1-benzazepena-1-acetic acid (CGS 16617)

The purpose of these experiments was to determine whether, in carotid arteries obtained from spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) a correlation exists between access of the angiotensin-converting enzyme (ACE) inhibitor, 3-[(5-amino-1-carboxy-1S-pentyl)amino]2,3,4,5-tetrahydro-2-oxo-3S- 1H-benzazepena-1-acetic acid (CGS 16617), to tissue sites and the corresponding responsiveness of these tissues to the contractile effect of angiotensin I (ANG I). In carotid arteries isolated from SHR and WKY, the magnitude of [14C]CGS 16617 uptake was slightly greater than the [14C]sucrose uptake (the extracellular space), and the percentages of [14C]CGS 16617 and [14C]sucrose in fast and slow desaturation components were similar. Addition of high concentrations of nonradioactive CGS 16617 (10(-5)M during uptakes or washouts of [14C]CGS 16617 did not change uptake amounts or efflux rates. The dose-response curves of contractions obtained with ANG I or ANG II as well as the dose-dependent inhibition of ANG I-induced responses in the presence of CGS 16617 were similar for carotids taken from both WKY and SHR. Responses to ANG I were restored as early as 5 min after incubation solutions containing inhibitory concentrations of CGS 16617 were removed. Similarly, normal responsiveness to the contractile effects of ANG I were observed with carotid arteries removed from SHR with decreased blood pressure and plasma ACE activity after 5 weeks exposure to CGS 16617. In contrast, however, responses to norepinephrine were decreased in carotid arteries obtained from CGS 16617-treated SHR.(ABSTRACT TRUNCATED AT 250 WORDS)

Stereoselective antimuscarinic effects of 3-quinuclidinyl atrolactate and 3-quinuclidinyl xanthene-9-carboxylate

The relative affinity and selectivity of the stereoisomers of 3-quinuclidinyl atrolactate (QNA) and the enantiomers of 3-quinuclidinyl xanthene-9-carboxylate (QNX) for the pharmacologically defined muscarinic receptor subtypes was determined using functional responses of rabbit vas deferens (M1), guinea pig atria (M2) and bladder detrusor muscle (M3). All the stereoisomers behaved as competitive antagonists yielding the same rank order of potency at each receptor subtype: (RR)-QNA greater than (RS)-QNA greater than (SR)-QNA greater than (SS)-QNA and (R)-QNX greater than (S)-QNX. Moreover, the eudismic ratios relative to (RR)-QNA for (RS)-, (SR)- and (SS)-QNA, respectively, ranged from 4 to 308 at all three subtypes. Stereoselective effects were also observed for QNX; (S)-QNX/(R)-QNX ratios ranged from 76 to 248. In contrast, there was a distinct lack of receptor selectivity among the isomers of QNA and QNX for either the M1, M2 or M3 muscarinic receptor subtypes. Stereoselective effects were also evident in vivo in the guinea pig cystometrogram, where the rank order of potency of the isomers of QNA and QNX was similar to that observed in vitro. (RR)-QNA and (R)-QNX equipotently depressed intravesical bladder pressure (PvesP) (ID50 = 0.06 mg/kg i.v.). Other parameters (bladder capacity, threshold pressure) were unaltered by the stereoisomers. The data demonstrate that despite the high affinity of the eutomers of QNA and QNX for muscarinic receptors, they discriminate poorly among muscarinic subpopulations, thus limiting their utility to subclassify muscarinic receptors.

Synthesis of some 3-(1-azabicyclo[2.2.2]octyl) 3-amino-2-hydroxy-2-phenylpropionates: profile of antimuscarinic efficacy and selectivity

A series of 3-quinuclidinyl atrolactate [3-(1-azabicyclo[2.2.2]octyl) 2-hydroxy-2-phenylpropionate, QNA] derivatives in which the methyl group of the parent is substituted with a tertiary amino substituent was prepared and tested for antimuscarinic activity. In general, potency was markedly decreased, although the morpholinyl and thiomorpholinyl derivatives retained significant activity. These compounds were also examined for muscarinic receptor subtype selectivity. Their subtype selectivities were comparable to that of (R,R)-QNA. The results of this investigation suggest possible differences in the accessory binding sites of the proteinaceous receptor subtypes.

Further improvements on the phosphotriester synthesis of deoxyribooligonucleotides and the oligonucleotide directed site-specific mutagenesis of E. coli lipoprotein gene

Two improvements that greatly enhance the rate of phosphotriester oligonucleotide synthesis are described: 1) use of hindered primary amines, e.g. t-butyl amine for decyanoethylation of oligonucleotide triester intermediates, and 2) a simplified isolation procedure that eliminates the tedious bicarbonate extraction after each condensing reaction. Using the improved procedures, oligonucleotide fragments can be synthesized as rapidly as using solid phase chemistry. The final products are purer than those obtained by solid phase chemistry since each intermediate block is purified by chromatography. The technique has been used to synthesize five oligonucleotide fragments (size 15 to 20) for the purpose of performing guided site-specific mutagenesis on a cloned E. coli lipoprotein gene.

Nimbus-7 Coastal Zone Color Scanner: System Description and Initial Imagery

The Coastal Zone Color Scanner (CZCS) on Nimbus-7, launched in October 1978, is the only sensor in orbit that is specifically designed to study living marine resources. The initial imagery confirms that CZCS data can be processed to a level that reveals subtle variations in the concentration of phytoplankton pigments. This development has potential applications for the study of large-scale patchiness in phytoplankton distributions, the evolution of spring blooms, water mass boundaries, and mesoscale circulation patterns.

25-hydroxy-vitamin D levels in a patient with hypervitaminosis D

We measured the concentrations of serum calcium and 25-hydroxy-vitamin D in a patient with hypervitaminosis D during 3 months of therapy directed toward correcting the hypercalcemia. Serum calcium could not be maintained at normal concentration without specific therapy until 9 weeks after vitamin D was discontinued. Concentration of 25-hydroxy-vitamin D at the time was 285 ng/ml, approximately half of the value measured three weeks after withdrawal of vitamin D. Serial measurements of the concentration of 25-hydroxy-vitamin D seem to be a useful means of assessing the degree of intoxication in patients with hypervitaminosis D.