Impact of malnutrition on the quality of life in older patients with advanced heart failure: a cohort study

OBJECTIVES

The aim of this study was to assess the prevalence of malnutrition, the clinical characteristics associated with malnutrition and the impact of nutritional status on mortality, quality of life, self-care abilities, and activities of daily living in the older patients with advanced heart failure.

METHODS

A prospective multicentre cohort study including 260 community-dwelling elderly patients with advanced HF was conducted between June 2017 and December 2019. The study was carried out in 22 primary healthcare centres, three university hospitals, one acute-care hospital, and one geriatric rehabilitation unit in the city of Barcelona (Spain). Nutritional status was assessed at baseline using the Mini Nutritional Assessment questionnaire. Patient-reported outcome measures included quality of life (EQ-5D-3L), self-care behaviour (European Heart Failure Self-care Behaviour Scale) and impact on activities of daily living (Barthel Index).

RESULTS

Using the MNA-SF, 126 (48.5%) patients were identified as being at risk of malnutrition and 33 (12.7%) patients as having confirmed malnutrition. Compared to HF patients with normal nutritional status, patients with confirmed malnutrition were significantly older, with a lower BMI, and with reduced haemoglobin levels. During follow-up (median 14.9 months, Interquartile Range; 4.9-26.9), 133 (51.2%) of the included participants died, and mortality was significantly higher among patients identified as having malnutrition (p < 0.001). Better Barthel index and quality of life scores were inversely related to the risk of malnutrition, [Odds Ratio (OR) 0.97 (95% Confidence interval 0.96; 0.98) and OR 0.98 (95% Confidence interval, 0.96; 0.99)], respectively. Higher scores in the European Heart Failure Self-care Behaviour Scale, which implies worse self care, were related to higher malnutrition risk, OR 1.05 (95% Confidence interval, 1.02; 1.09. Adjusted multivariate logistic model found that malnutrition was significantly associated with poor quality of life, and adverse impacts on daily activities and self-care.

CONCLUSIONS

In community-dwelling older patients with advanced HF, malnutrition was associated with worse patient reported outcome measures related to poor quality of life, and adverse impacts on self-care and daily activities. Nutritional status must be systematically addressed by primary care nurses and family doctors to improve survival rates in these patients. It would be helpful the incorporation of expert professionals in nutrition in the primary health care centres.

Caffeinated coffee consumption and risk of atrial fibrillation in two Spanish cohorts

AIMS

The association between caffeinated coffee consumption and atrial fibrillation remains unclear. Recent studies suggest an inverse association only between a moderate caffeinated coffee consumption and atrial fibrillation, but others have reported no association. The aim of our study was to prospectively assess the association between caffeinated coffee consumption and atrial fibrillation in two Spanish cohorts, one of adults from a general population and another of elderly participants at high cardiovascular risk.

METHODS AND RESULTS

We included 18,983 and 6479 participants from the 'Seguimiento Universidad de Navarra' (SUN) and 'Prevención con Dieta Mediterránea' (PREDIMED) cohorts, respectively. Participants were classified according to their caffeinated coffee consumption in three groups: ≤3 cups/month, 1-7 cups/week, and >1 cup/day. We identified 97 atrial fibrillation cases after a median follow-up of 10.3 years (interquartile range 6.5-13.5), in the SUN cohort and 250 cases after 4.4 years median follow-up (interquartile range 2.8-5.8) in the PREDIMED study. No significant associations were observed in the SUN cohort although a J-shaped association was suggested. A significant inverse association between the intermediate category of caffeinated coffee consumption (1-7 cups/week) and atrial fibrillation was observed in PREDIMED participants with a multivariable-adjusted hazard ratio = 0.53 (95% confidence interval 0.36-0.79) when compared with participants who did not consume caffeinated coffee or did it only occasionally. No association was found for higher levels of caffeinated coffee consumption (>1 cup per day), hazard ratio = 0.79 (95% confidence interval 0.49-1.28). In the meta-analysis of both PREDIMED and SUN studies, the hazard ratio for intermediate consumption of caffeinated coffee was 0.60 (95% confidence interval 0.44-0.82) without evidence of heterogeneity. Similar findings were found for the association between caffeine intake and atrial fibrillation risk.

CONCLUSION

Intermediate levels of caffeinated coffee consumption (1-7 cups/week) were associated with a reduction in atrial fibrillation risk in two prospective Mediterranean cohorts.

Mediterranean alcohol-drinking pattern, low to moderate alcohol intake and risk of atrial fibrillation in the PREDIMED study

BACKGROUND AND AIMS

There is ongoing controversy about the effect of a low to moderate alcohol consumption on atrial fibrillation (AF). Our aim is to assess the association between adherence to a Mediterranean alcohol drinking pattern and AF incidence.

METHODS AND RESULTS

A total 6527 out of the 7447 participants in the PREDIMED trial met our inclusion criteria. A validated frequency food questionnaire was used to measure alcohol consumption. Participants were classified as non-drinkers, Mediterranean alcohol drinking pattern (MADP) (10-30 g/d in men and 5-15 g/day in women, preferably red wine consumption with low spirits consumption), low-moderate drinking (<30 g/day men y and < 15 g/day women), and heavy drinking. We performed multivariable Cox regression models to estimate hazard ratios (HR) with 95% confidence intervals (95% CI) of incident AF according to alcohol drinking patterns. After a mean follow up of 4.4 years, 241 new incident AF cases were confirmed. Alcohol consumption was not associated to AF incidence among low-moderate drinkers (HR: 0.96; 95%CI: 0.67-1.37), adherents to MADP (HR: 1.15 95%CI: 0.75-1.75), or heavy drinkers (HR: 0.92; 95%CI: 0.53-1.58), compared with non-drinkers.

CONCLUSIONS

In a high cardiovascular risk adult population, a Mediterranean alcohol consumption pattern (low to moderate red wine consumption) was not associated with an increased incidence of AF.

CLINICAL TRIALS

URL: http://www.controlled-trials.com. Unique identifier: ISRCTN35739639.

Head movement measurement: An alternative method for posturography studies

The present study evaluated the measurement of head movements as a valid method for postural emotional studies using the comparison of simultaneous recording of center of pressure (COP) sway as criterion. Thirty female students viewed a set of 12 pleasant, 12 unpleasant and 12 neutral pictures from the International Affective Picture System, repeated twice, using a block presentation procedure while standing on a force platform (AMTI AccuSway). Head movements were recorded using a webcam (©KPC139E) located in the ceiling in line with the force platform and a light-emitting diode (LED) placed on the top of the head. Open source software (CvMob 3.1) was used to process the data. High indices of correlation and coherence between head and COP sway were observed. In addition, pleasant pictures, compared with unpleasant pictures, elicited greater body sway in the anterior-posterior axis, suggesting an approach response to appetitive stimuli. Thus, the measurement of head movement can be an alternative or complementary method to recording COP for studying human postural changes.

Stability, nutrient availability and hydrophobicity of biochars derived from manure, crop residues, and municipal solid waste for their use as soil amendments

We aimed to study the influence of feedstock properties, pyrolysis temperature and holding time on stability, nutrient contents and hydrophobicity of biochars derived from pig manure, crop residues and municipal solid waste. Biochars were prepared at 300 °C, 400 °C, 500 °C and 700 °C for 1 h, 2 h, 4 h and 5 h. All properties were influenced by feedstock except for pH and hydrophobicity. Temperature influenced all properties, whereas no effect of holding time was observed except for hydrophobicity and thermal stability. Increasing temperature increased aromatization and stability. Low temperatures provided higher cation exchange capacity and available nutrients, and lower salinity and alkalinity. Precipitation of phosphates and carbonates occurred with charring, explaining the decrease of available nutrients. Biochars produced at 300 °C showed high hydrophobity, which disappeared over 500 °C owing to the loss of labile aliphatic compounds. The high pH and carbonates contents at >500 °C resulted in suitable biochars for soil liming and decreasing soil metals availability.

Does the Mediterranean diet counteract the adverse effects of abdominal adiposity?

BACKGROUND AND AIM

We tested the hypothesis that an intervention with a Mediterranean diet (MeDiet) could mitigate the well-known harmful effects of abdominal obesity on cardiovascular health.

METHODS AND RESULTS

We assessed the relationship between baseline waist-to-height ratio (WHtR) and major cardiovascular events during a median follow-up of 4.8 years in the Prevention with Mediterranean Diet (PREDIMED) randomized primary prevention trial, which tested a MeDiet against a control diet (advice on a low-fat diet). We also examined whether the MeDiet intervention was able to counteract the detrimental cardiovascular effects of an increased WHtR. The trial included 7447 participants (55-80 years old, 57% women) at high cardiovascular risk but free of cardiovascular disease (CVD) at enrollment. An increased risk of CVD events (myocardial infarction, stroke, or cardiovascular death) was apparent for the highest versus the lowest quartile of WHtR (multivariable-adjusted hazard ratio: 1.98) (95% confidence interval: 1.10-3.57; linear trend: p = 0.019) only in the control-diet group, but not in the two groups allocated to intervention with MeDiet (p for interaction = 0.034). This apparent interaction suggesting that the intervention counterbalanced the detrimental cardiovascular effects of adiposity was also significant for body mass index (BMI) (p = 0.01) and waist circumference (p = 0.043).

CONCLUSIONS

The MeDiet may counteract the harmful effects of increased adiposity on the risk of CVD.

In vitro longevity of bonding properties of universal adhesives to dentin

PURPOSE

To evaluate the immediate and 6-month resin-dentin bond strength (μTBS) and nanoleakage (NL) of universal adhesives that contain or do not contain methacryloyloxydecyl dihydrogen phosphate (MDP) and are used in the etch-and-rinse and self-etch strategies.

METHODS AND MATERIALS

Forty caries-free extracted third molars were divided into eight groups for μTBS (n=5). The groups were bonded with the Clearfil SE Bond (CSE) and Adper Single Bond 2 (SB) as controls; Peak Universal, self-etch (PkSe) and etch-and rinse (PkEr); Scotchbond Universal Adhesive, self-etch (ScSe) and etch-and-rinse (ScEr); and All Bond Universal, self-etch (AlSe) and etch-and-rinse (AlEr). After composite restorations, specimens were longitudinally sectioned to obtain resin-dentin bonded sticks (0.8 mm(2)). The μTBS of the specimens was tested immediately (IM) or after 6 months of water storage (6M) at 0.5 mm/min. Some sticks at each storage period were immersed in silver nitrate and photo developed, and the NL was evaluated with scanning electron microscopy. Data were analyzed with two-way repeated-measures analysis of variance and Tukey test (α=0.05).

RESULTS

At the IM period, PkSe and PkEr showed μTBS similar to the control adhesives (p>0.05) but increased NL pattern and lower μTBS after 6M (p<0.05). ScSe and ScEr showed intermediary μTBS values at the IM period but remained stable after 6 months (p>0.05). AlSe showed the lowest μTBS (p<0.05), but μTBS and NL remained stable after 6M (p>0.05). AlEr showed higher IM μTBS but showed higher degradation after 6M (p<0.05).

CONCLUSIONS

Universal adhesives that contain MDP showed higher and more stable μTBS with reduced NL at the interfaces after 6 months of water storage.

[Obesity and anthropometric indicators in a sample of males with Acute Coronary Syndrome in a health area with inclusion of inmates: case-control study]

OBJECTIVES

Obesity is a cardiovascular risk factor with a high epidemic burden on ischemic heart disease. The aim of this study was to analyze the anthropometric indicators of obesity in a sample of males who have had an Acute Coronary Syndrome (ACS) diagnosed in a prison referral hospital, and a control group.

MATERIAL AND METHODS

Cross-sectional case-control study in a Health Area with inclusion of a penitentiary center. The participants in this study were 204 males, 102 cases and one control selected for each case (n=102). We measured weight, height waist circumference (WC), umbilical waist (UW) and hip circumference. We calculated body mass index (BMI) and other anthropometric indicators: waist to-hip-ratios (WHR and UWHR), waist to-height-ratios (WHtR and UWHtR). We obtained the areas under the receiver operating characteristic curves (AUC), the odds ratio (OR) and the correlations in the infarcted people.

RESULTS

Obesity was more prevalent in ACS (31.4% vs 9.1%; OR: 4.7). Other indicators show a discriminatory association. BMI (AUC: 0.699; OR: 3.9), WC (AUC: 0.750; OR: 6.3), UW (AUC: 0.777; OR: 10), inverse height (AUC: 0.619; OR: 2.1), WHR (AUC: 0.832; OR: 11.6); UWHR (AUC: 0.857; OR: 15.6), UWHtR (AUC: 0.800; OR: 8.9). In ACS the correlations for both WC and UW with waist to-height-ratios (WHtR and UWHtR) were strong (all r ≥0.90; p < 0.001).

DISCUSSION

The anthropometric indicators of obesity are clearly associated with ACS. UW is the simple measurement with the best association. BMI is most weakly associated. UWHtR presents high discriminatory power and the best anthropometric correlation of risk that supports its use for the identification of males at risk of myocardial infarction in the general population and prison.

A comprehensive laboratory screening of three-step etch-and-rinse adhesives

OBJECTIVES

This study evaluated several bonding (microtensile bond strengths [μTBS], nanoleakage [NL], and in situ degree of conversion [ISDC] on dentin) and mechanical properties (ultimate tensile strength [UTS], degree of conversion [DC], water sorption [WS], and solubility [SL] in water) of four three-step etch-and-rinse adhesives in the short term.

METHODS

A total of 28 molars were used in this study. The dentin surfaces were bonded with the following adhesives: All-Bond 3 (ALB3); Fusion Duralink (FSDL); Optibond FL (OBFL), and Scotchbond Multi-Purpose (SBMP). After each adhesive-system application, composite resin build-ups were added. For bonding tests, specimens were sectioned in order to obtain bonded sticks. The sticks were divided to be tested for μTBS (0.5 mm/min), for NL (n=2), and ISDC (n=2). For NL, they were immersed in 50% silver nitrate and analyzed by scanning election microscopy. For ISDC, the hybrid layer was evaluated by micro-Raman spectroscopy. An hourglass-shaped matrix (UTS) or disk-shaped matrix (WS and SL) was filled with primer and adhesive (1:1 ratio) and light-polymerized. For UTS evaluation, the specimens were tested under tension. For WS and SL, specimens were desiccated and stored in distilled water to evaluate water diffusion kinetics over a 28-day period. The DC of the adhesives was evaluated by Fourier transformed infrared spectroscopy. The data from each test were analyzed by appropriate statistical methods.

RESULTS

OBFL resulted in the highest μTBS, lower NL, higher ISDC and DC, and higher UTS than other adhesives (p<0.05), as well as lower WS (similar to ALB3 and FSDL) and SL (similar to ALB3 and SBMP) (p>0.05). ALB3 showed a higher NL and the lowest DC value. FSDL showed the highest NL and SL and the lowest ISDC. SBMP showed the lowest pattern of WS (p<0.05)CONCLUSION: OBFL showed the best results in all the properties evaluated, and it can be considered the gold standard of the three-step etch-and-rinse adhesive systems.

Immediate adhesive properties to dentin and enamel of a universal adhesive associated with a hydrophobic resin coat

OBJECTIVES

To evaluate the effect of acid etching and application of a hydrophobic resin coat on the enamel/dentin bond strengths and degree of conversion (DC) within the hybrid layer of a universal adhesive system (G-Bond Plus [GB]).

METHODS

A total of 60 extracted third molars were divided into four groups for bond-strength testing, according to the adhesive strategy: GB applied as a one-step self-etch adhesive (1-stepSE); GB applied as in 1-stepSE followed by one coat of the hydrophobic resin Heliobond (2-stepSE); GB applied as a two-step etch-and-rinse adhesive (2-stepER); GB applied as in 2-stepER followed by one coat of the hydrophobic resin Heliobond (3-stepER). There were 40 teeth used for enamel microshear bond strength (μSBS) and DC; and 20 teeth used for dentin microtensile bond strength (μTBS) and DC. After restorations were constructed, specimens were stored in water (37°C/24 h) and then tested at 0.5 mm/min (μTBS) or 1.0 mm/min (μSBS). Enamel-resin and dentin-resin interfaces from each group were evaluated for DC using micro-Raman spectroscopy. Data were analyzed with two-way analysis of variance for each substrate and the Tukey test (α=0.05).

RESULTS

For enamel, the use of a hydrophobic resin coat resulted in statistically significant higher mean enamel μSBS only for the ER strategy (3-stepER vs 2-stepER, p<0.0002). DC was significantly improved for the SE strategy (p<0.00002). For dentin, the use of a hydrophobic resin coat resulted in significantly higher dentin mean μTBS only for the SE strategy (2-stepSE vs 1-stepSE, p<0.0007). DC was significantly improved in groups 2-stepSE and 3-stepER when compared with 1-stepSE and 2-stepER, respectively (p<0.0009).

CONCLUSIONS

The use of a hydrophobic resin coat may be beneficial for the selective enamel etching technique, because it improves bond strengths to enamel when applied with the ER strategy and to dentin when used with the SE adhesion strategy. The application of a hydrophobic resin coat may improve DC in resin-dentin interfaces formed with either the SE or the ER strategy. On enamel, DC may benefit from the application of a hydrophobic resin coat over 1-stepSE adhesives.

Dietary intake and major food sources of polyphenols in a Spanish population at high cardiovascular risk: the PREDIMED study

BACKGROUND AND AIMS

Epidemiological data have shown an inverse association between the consumption of polyphenol-rich foods and the risk of cardiovascular disease or overall mortality. A comprehensive estimation of individual polyphenol intake in nutritional cohorts is needed to gain a better understanding of this association. The aim of this study was to estimate the quantitative intake of polyphenols and the major dietary sources in the PREDIMED (PREvención con DIeta MEDiterránea) cohort using individual food consumption records.

METHODS AND RESULTS

The PREDIMED study is a large, parallel-group, multicentre, randomised, controlled 5-year feeding trial aimed at assessing the effects of the Mediterranean diet on the primary prevention of cardiovascular disease. A total of 7200 participants, aged 55-80 years, completed a validated 1-year food frequency questionnaire (FFQ) at baseline. Polyphenol consumption was calculated by matching food consumption data from the FFQ with the recently developed Phenol-Explorer database on polyphenol content in foods. The mean total polyphenol intake was 820 ± 323 mg day⁻¹ (443 ± 218 mg day⁻¹ of flavonoids and 304 ± 156 mg day⁻¹ of phenolic acids). Hydroxycinnamic acids were the phenolic group with the highest consumption and 5-caffeoylquinic acid was the most abundantly ingested individual polyphenol. The consumption of olives and olive oil was a differentiating factor in the phenolic profile of this Spanish population compared with other countries.

CONCLUSION

In Mediterranean countries, such as Spain, the main dietary source of polyphenols is coffee and fruits, but the most important differentiating factor with respect to other countries is the consumption of polyphenols from olives and olive oil.

Spontaneously broken neutral symmetry in an ecological system

Spontaneous symmetry breaking plays a fundamental role in many areas of condensed matter and particle physics. A fundamental problem in ecology is the elucidation of the mechanisms responsible for biodiversity and stability. Neutral theory, which makes the simplifying assumption that all individuals (such as trees in a tropical forest)--regardless of the species they belong to--have the same prospect of reproduction, death, etc., yields gross patterns that are in accord with empirical data. We explore the possibility of birth and death rates that depend on the population density of species, treating the dynamics in a species-symmetric manner. We demonstrate that dynamical evolution can lead to a stationary state characterized simultaneously by both biodiversity and spontaneously broken neutral symmetry.

Effect of bur roughness on bond to sclerotic dentin with self-etch adhesive systems

PURPOSE

To evaluate the effect of bur roughness on bond strength values and conditioner pattern of two-step self-etch adhesives applied on sclerotic dentin.

METHODS

The roots of 48 bovine incisors were removed and the crowns were divided into four groups: the control group (CO) teeth were left untreated or the teeth were slightly roughened with coarse-, medium-, or fine-grit diamond burs. Next, the teeth were subdivided and Clearfil SE Bond (CSE) and Adper SE Bond (ASE) were applied according to the manufacturers' instructions. Composite resin (Opallis) buildups were incrementally constructed on the bonded surfaces. After storage for 24 hours in distilled water at 37°C, the teeth were sectioned into sticks (area of 0.8 mm(2)). The sticks were stressed until failure by tensile forces (0.5 mm/min). Additionally, eight bovine teeth were treated as previously described, and after adhesive application, the surface was rinsed off and examined by scanning electron microscopy to measure the relative number of open tubules (OT). Data (MPa) were analyzed by two-way analysis of variance and Tukey test (p=0.05).

RESULTS

CO showed the highest bond strength values (p<0.05). As regards OT, the lowest mean was observed for CO (p<0.05) and the highest was found after application of CSE or ASE (p<0.05).

A fluorescence study of the molecular interactions of harmane with the nucleobases, their nucleosides and mononucleotides

Fluorescence binding studies of harmane to the elemental components of the nucleic acids were undertaken to investigate the origin of the interaction between the drug and DNA. Most of the tested substrates have been found to induce hypochromism in the absorption spectrum of harmane and to quench its fluorescence. The quenching process induced by the nucleobases and their nucleosides is mainly due to the formation of ground state 1:1 complexes. However, in the case of the mononucleotides a dynamic quenching component is also observed. This quenching component is likely due to the excited state interaction of harmane with the phosphate group of the nucleotides. UV-vis spectral changes and quenching measurements have been used to quantify the ground state association constants of the complexes and the quenching rate constants.

Sitosterol xanthomatosis

BACKGROUND

Sitosterolaemia is a lipid disorder in which plasma plant sterol levels are extremely elevated. Sitosterolaemia is clinically characterized by tuberous and tendon xanthomas, premature vascular disease and arthritis.

OBJECTIVE

To report a case of sitosterolaemia diagnosed by cutaneous manifestations and to review this rare disease.

METHODS

We report the case of a 60-year-old woman who presented with cutaneous xanthomas, arterial hypertension and polyarthralgias. The patient had had hypercholesterolaemia for many years without reduction of serum cholesterol, despite treatment with fenofibrate.

RESULTS

Ezetimibe therapy was started, decreasing sitosterol plasmatic levels and tuberous xanthomas after 3 months of treatment.

CONCLUSION

It is important to detect levels of sitosterol in plasma in patients with premature vascular disease, presence of xanthomas, and uncontrolled hypercholesterolaemia. Ezetimibe therapy is effective.

Effects of static and dynamic disorder on the performance of neural automata

We report on both analytical and numerical results concerning stochastic Hopfield-like neural automata exhibiting the following (biologically inspired) features: (1) Neurons and synapses evolve in time as in contact with respective baths at different temperatures; (2) the connectivity between neurons may be tuned from full connection to high random dilution, or to the case of networks with the small-world property and/or scale-free architecture; and (3) there is synaptic kinetics simulating repeated scanning of the stored patterns. Although these features may apparently result in additional disorder, the model exhibits, for a wide range of parameter values, an extraordinary computational performance, and some of the qualitative behaviors observed in natural systems. In particular, we illustrate here very efficient and robust associative memory, and jumping between pattern attractors.

Therapeutic immunization with an inactivated HIV-1 Immunogen plus antiretrovirals versus antiretroviral therapy alone in asymptomatic HIV-infected subjects

To determine whether the addition of an inactivated-gp120-depleted HIV-1 Immunogen to antiretrovirals (ARTs) conferred a beneficial effect on delaying time to virologic failure relative to that obtained by ARTs alone, a phase II clinical trial was performed in 243 asymptomatic, ART naïve, HIV-1 seropositive adults. The Cox model showed that HIV-1 Immunogen treatment was associated with a 34% decrease in the risk of virologic failure (P = 0.056). When the analysis incorporated baseline HIV-RNA stratification the risk of virologic failure in the HIV-1 Immunogen Arm was significantly reduced a 37% compared to the IFA placebo Arm (P = 0.034). The data suggest that therapeutic immunization plus ARTs could influence virologic control.

Hydrogen bonding interactions between indole and benzenoid-pi-bases

The NH-pi interactions of indole with benzene, naphthalene, phenanthrene, toluene, m-xylene, and mesitilene, in carbon tetrachloride solutions, have been studied by Fourier transform infrared spectroscopy. The experiments, carried out on the NH stretching band of indole, prove the formation of 1:1 complexes in which the NH bond of indole is engaged. The NH frequency shifts are independent of the number of rings in the base, but they progressively increase as the electron density is enhanced by methylation. The association constants increase with the increase of both, the number of rings and the methyl groups on the base. At higher base concentrations, further shifts on the free NH and associated bands indicate the formation of 1:2 complexes, which suggest hybride NH-pi and van der Waals interactions between one indole ring and two benzene acceptor molecules.

Results of kidney transplantation in recipients over 70 years of age: experience at a single center

We performed 41 kidney transplants in patients >70 years (35 single and 6 dual), with a mean recipient age of 72+/-2 years, from January 1990 to December 2001. Mean age of the donors was 69+/-12 years. Immunosuppression used triple therapy with steroids, mycophenolate mofetil, and cyclosporine or tacrolimus. Cold ischemia time was 23+/-3 hours. The incidence of primary nonfunction was 4.8%, and delayed graft function 58.5%. Acute rejection incidence was 12%. The actuarial patient survival rates at 12, 24, and 36 months were 82.5%, 82.5%, and 75%, respectively. Actuarial survival rates of the grafts censuring for death of the recipient with a functioning graft were 89.5%, 86%, and 68%, respectively. Nine of the 18 graft losses were due to recipient death. Overall, renal transplant recipients >70 years showed good results. The principal cause of graft loss was recipient death.

Nonequilibrium wetting transitions with short range forces

We analyze within mean-field theory as well as numerically a Kardar-Parisi-Zhang equation that describes nonequilibrium wetting. Both complete and critical wettitng transitions were found and characterized in detail. For one-dimensional substrates the critical weting temperature is depressed by fluctuations. In addition, we have investigated a region in the space of parameters (temperature and chemical potential) where the wet and nonwet phases coexist. Finite-size scaling analysis of the interfacial detaching times indicates that the finite coexistence region survives in the thermodynamic limit. Within this region we have observed (stable or very long lived) structures related to spatiotemporal intermittency in other systems. In the interfacial representation these structures exhibit perfect triangular (pyramidal) patterns in one dimension (two dimensions), which are characterized by their slope and size distribution.

Scale-free networks from varying vertex intrinsic fitness

A new mechanism leading to scale-free networks is proposed in this Letter. It is shown that, in many cases of interest, the connectivity power-law behavior is neither related to dynamical properties nor to preferential attachment. Assigning a quenched fitness value x(i) to every vertex, and drawing links among vertices with a probability depending on the fitnesses of the two involved sites, gives rise to what we call a good-get-richer mechanism, in which sites with larger fitness are more likely to become hubs (i.e., to be highly connected).

Is the particle current a relevant feature in driven lattice gases?

By performing extensive Monte Carlo simulations we show that the infinitely fast driven lattice gas (IDLG) shares its critical properties with the randomly driven lattice gas (RDLG). All the measured exponents, scaling functions, and amplitudes are the same in both cases. This strongly supports the idea that the main relevant nonequilibrium effect in driven lattice gases is the anisotropy (present in both IDLG and RDLG) and not the particle current (present only in the IDLG). This result, at odds with the predictions from the standard theory for the IDLG, supports a recently proposed alternative theory. The case of finite driving fields is also briefly discussed.

Critical behavior of a one-dimensional fixed-energy stochastic sandpile

We study a one-dimensional fixed-energy version (that is, with no input or loss of particles) of Manna's stochastic sandpile model. The system has a continuous transition to an absorbing state at a critical value of the particle density, and exhibits the hallmarks of an absorbing-state phase transition, including finite-size scaling. Critical exponents are obtained from extensive simulations, which treat stationary and transient properties, and an associated interface representation. These exponents characterize the universality class of an absorbing-state phase transition with a static conserved density in one dimension; they differ from those expected at a linear-interface depinning transition in a medium with point disorder, and from those of directed percolation.

Fibrosing cholestatic hepatitis-like syndrome in hepatitis B virus-negative and hepatitis C virus-negative renal transplant recipients

Cholestatic hepatitis and diffuse liver fibrosis have been described in immunosuppressed patients with hepatitis B virus or hepatitis C virus infection as fibrosing cholestatic hepatitis (FCH). FCH is characterized by cholestasis, with only a modest increase in aminotransferase levels. The pathologic picture typically shows periportal and perisinusoidal fibrosis, scarce mixed infiltrates, hepatocellular ballooning, and histologic cholestasis. We report two patients with diffuse fibrosis and cholestasis quite similar to the histologic picture of FCH, but in whom neither hepatitis B virus nor hepatitis C virus infection could be shown, highlighting the potential contribution of cytomegalovirus infection and azathioprine toxicity in the development of this severe complication of solid-organ transplantation.

Field theory of self-organized fractal etching

We propose a phenomenological field theoretical approach to the chemical etching of a disordered solid. The theory is based on a recently proposed dynamical etching model. Through the introduction of a set of Langevin equations for the model evolution, we are able to map the problem into a field theory related to isotropic percolation. To the best of the author's knowledge, this constitutes the first application of field theory to a problem of chemical dynamics. By using this mapping, many of the etching process critical properties are seen to be describable in terms of the percolation renormalization group fixed point. The emerging field theory has the peculiarity of being self-organized in the sense that without any parameter fine tuning the system develops fractal properties up to a certain scale controlled solely by the volume V of the etching solution. In the limit V-->infinity the upper cutoff goes to infinity and the system becomes scale invariant. We present also a finite size scaling analysis and discuss the relation of this particular etching mechanism to gradient percolation. Finally, the possibility of considering this mechanism as a generic path to self-organized criticality is analyzed, with the characteristics of being closely related to a real physical system and therefore more directly accessible to experiments.

Hydrogen bonding NH/pi interactions between betacarboline and methyl benzene derivatives

In the presence of benzene, toluene, m-xylene, mesitylene and durene, the pyrrolic NH stretching band of betacarboline, 9H-pyrido[3,4-b]indole, and its 1-methyl derivative, harmane, in tetrachloroethane diminishes in intensity while a new red-shifted band grows up. The shifts of the associated bands increase linearly with the pi-electron density of the substrates. These spectral changes are attributed to the formation of 1:1 molecular association complexes between the betacarbolines and the benzenoid substrates. The complexes are stabilized by the hydrogen-bonding interaction between the pyrrolic NH group of betacarboline and the pi-delocalized electrons of the benzene derivatives. The influence of these NH/pi hydrogen-bonding interactions in the fluorescence spectra of betacarboline is discussed.

Numerical study of persistence in models with absorbing states

Extensive Monte Carlo simulations are performed in order to evaluate both the local (straight theta(l)) and global (straight theta(g)) persistence exponents in the Ziff-Gulari-Barshad (ZGB) [Phys. Rev. Lett. 56, 2553 (1986)] irreversible reaction model. At the second-order irreversible phase transition (IPT) we find that both the local and the global persistence exhibit power-law behavior with a crossover between two different time regimes. On the other hand, at the ZGB first-order IPT, active sites are short lived and the persistence decays more abruptly; it is not clear whether it shows power-law behavior or not. In order to analyze universality issues, we have also studied another model with absorbing states, the contact process, and evaluated the local persistence exponent in dimensions from 1 to 4. A striking apparent superuniversality is reported: the local persistence exponent seems to coincide in both one- and two-dimensional systems. Some other aspects of persistence in systems with absorbing states are also analyzed.

[Experience in the treatment of 98 carcinomas of the nasopharynx. Long-term follow-up and analysis of prognostic factors]

This was a retrospective study of 98 patients (pts.) with histologically confirmed nasopharyngeal carcinoma. The clinico-demographic characteristics were: median age of 53 years (11-83); 74 males and 24 females (ratio 3:1); histology subtype OMS 2-3 in 89 pts. (90.8%); cranial nerve deficits in 11 pts. (11.2%); 50 (51%) were stage T3T4; 68 pts. (69.4%) N2N3 and 77 pts. (78.6%) stage IV. The therapeutic modalities were: radical radiotherapy (RT) alone in 42 pts., chemotherapy (CT) alone in 4 pts., RT + adjuvant CT in 10 pts. and neoadjuvant CT + RT in 42 pts. RT was delivered in wide fields, doses between 50-75 Gy with conventional fractionation. CT consisted in cisplatinum-based schedules (PF in 34 pts., BEC in 9 and others in 13 pts.). Analyzed by treatment, more males and stages N2N3 and IV were accrued in neoCT + RT arm (p < or = 0.05). For the entire population, the overall complete response was achieved in 65 pts. (66.3%); in 27/35 pts. (77.1%) of the RT group and 30/51 pts. (58.8%) of CT + RT group (p 0.07) of pts. with III-IV stages. With a median follow-up of 74.5 months, 32 pts. (32.65%) are alive and free of disease. The projected OS for all pts. was 40 months (m), 51.4% at 3 years (y) and 45.5% at 5 y with a disease free survival of 37 m (0-236). No differences between treatment arms were found (p 0.4). In univariant analysis for OS in stage III-IV pts., age > 50 y, histology OMS1, cranial nerve deficits, stage T3T4 and N2N3, were considered adverse prognostic factors (p < or = 0.05). In multivariant analysis, only age > 50 y and stages T3-T4, N2-N3 were significant (p < or = 0.05). In conclusion, we demonstrated good long term survival without any differences among treatment modalities in pts. with advanced nasopharyngeal carcinomas. New therapeutic approaches are warranted in order to improve the outcome of this patients.

Normal values for serum, ultrafilterable and intraerythrocytic magnesium in children

Serum magnesium (MgS), levels were determined in 137 children age range 2 months to 16 years. Ultrafilterable magnesium (MgU) and intraerythrocytic magnesium (MgI) concentrations were determined in 37 of these children. MgS was 0.83 +/- 0.1 mmol/L (range 0.66-1.36 mmol/L), with no differences between sexes. Children under 2 years had higher MgS levels (0.92 +/- 0.13 mmol/L) than children over 2 years (0.81 +/- 0.08 mmol/L; p < .001). Mean MgU was 0.60 +/- 0.07 mmol/L (range 0.50-0.87 mmol/L), with no differences between sexes. Mean MgI in children was 2.58 +/- 0.33 mmol/L (range 2.06-3.6 mmol/L), with no differences between sexes. MgS correlated with MgU, age, theoretical growth rate, and serum calcium, phosphorus and alkaline phosphatase; MgU correlated with MgI, age, theoretical growth rate, and serum phosphorus. MgS concentration was higher in children under 2 years than in children over 2 years. In healthy children, MgS concentration correlated with MgU, and MgU correlated with MgI, but MgS and MgI showed no correlation.

Serum endothelial adhesion molecules levels correlate with lesion burden in multiple sclerosis patients treated with interferon beta-1b

The levels of serum-soluble intracellular adhesion molecule-1 and soluble endothelial-leukocyte adhesion molecule-1, and the Gadolinium-enhanced T1-weighted MRI were studied in a group of patients with relapsing-remitting multiple sclerosis treated with interferon beta-1b and compared to a non-treated control group. The levels of serum-soluble intracellular adhesion molecule-1 and soluble endothelial-leukocyte adhesion molecule-1 increased, after three months treatment, as compared to baseline and the non-treated MS patients. A significant correlation was found in the treated group between serum-soluble endothelial-leukocyte adhesion molecule-1 and the lesion area in the Gadolinium-enhancing (T2 weighted scan) MRI.

A spectroscopic study of the molecular interactions of harmane with pyrimidine and other diazines

FTIR, UV-vis, steady state and time-resolved fluorescence measurements show that harmane (1-methyl-9H-pyrido/3,4-b/indole) interacts with pyrimidine and its isomers pyrazine and pyridazine in its ground and lowest singlet states. The mechanisms of interaction are dependent on both the structure of the diazine and the nature of the solvent. Thus, in a low polar solvent such as toluene, harmane forms ground state 1:1 hydrogen-bonded complexes with all the diazines. These complexes quench the fluorescence of harmane and diminish its fluorescence lifetime. Conversely, in buffered (pH 8.7) aqueous solutions, pyrimidine behaves differently from the other diazines. Thus, whereas pyrimidine only interacts with harmane in its ground state, pyrazine and pyridazine also interact in the excited state. The harmane-pyrimidine ground state interaction is an entropic controlled process. Therefore, we propose the formation of pi-pi stacked 1:1 complexes between these substrates. Association constants for the different types of complexes and quenching parameters are reported.

Renormalization-group study of one-dimensional systems with roughening transitions

A recently introduced real-space renormalization-group technique, developed for the analysis of processes in the Kardar-Parisi-Zhang universality class, is generalized and tested by applying it to a different family of surface-growth processes. In particular, we consider a growth model exhibiting a rich phenomenology even in one dimension. It has four different phases and a directed percolation-related roughening transition. The renormalization method reproduces extremely well all of the phase diagram, the roughness exponents in all the phases, and the separatrix among them. This proves the versatility of the method and elucidates interesting physical mechanisms.

Recent results on multiplicative noise

Recent developments in the analysis of Langevin equations with multiplicative noise (MN) are reported. In particular, we (i) present numerical simulations in three dimensions showing that the MN equation exhibits, like the Kardar-Parisi-Zhang (KPZ) equation, both a weak coupling fixed point and a strong coupling phase, supporting the proposed relation between MN and KPZ; (ii) present a dimensional and mean-field analysis of the MN equation to compute critical exponents; (iii) show that the phenomenon of the noise-induced ordering transition associated with the MN equation appears only in the Stratonovich representation and not in the Ito one; and (iv) report the presence of a first-order-like phase transition at zero spatial coupling, supporting the fact that this is the minimum model for noise-induced ordering transitions.

Scale invariant dynamics of surface growth

We describe in detail and extend a recently introduced nonperturbative renormalization group (RG) method for surface growth. The scale invariant dynamics which is the key ingredient of the calculation is obtained as the fixed point of a RG transformation relating the representation of the microscopic process at two different coarse-grained scales. We review the RG calculation for systems in the Kardar-Parisi-Zhang (KPZ) universality class and compute the roughness exponent for the strong coupling phase in dimensions from 1 to 9. Discussions of the approximations involved and possible improvements are also presented. Moreover, very strong evidence of the absence of a finite upper critical dimension for KPZ growth is presented. Finally, we apply the method to the linear Edwards-Wilkinson dynamics where we reproduce the known exact results, proving the ability of the method to capture qualitatively different behaviors.

Avalanche and spreading exponents in systems with absorbing states

We present generic scaling laws relating spreading critical exponents and avalanche exponents (in the sense of self-organized criticality) in general systems with absorbing states. Using these scaling laws we present a collection of the state-of-the-art exponents for directed percolation, dynamical percolation, and other universality classes. This collection of results should help to elucidate the connections of self-organized criticality and systems with absorbing states. In particular, some nonuniversality in avalanche exponents is predicted for systems with many absorbing states.

Sample Size Requirements of a Mixture Analysis Method with Applications in Systematic Biology

The available information on sample size requirements of mixture analysis methods is insufficient to permit a precise evaluation of the potential problems facing practical applications of mixture analysis. We use results from Monte Carlo simulation to assess the sample size requirements of a simple mixture analysis method under conditions relevant to biological applications of mixture analysis. The mixture model used includes two univariate normal components with equal variances but assumes that the researcher is ignorant as to the equality of the variances. The method used relies on the EM algorithm to compute the maximum likelihood estimates of the mixture parameters, and the likelihood ratio test to assess the number of components in the mixtures. Our results suggest that sample sizes close to 500 or 1000 data may be required to adequately solve mixtures commonly found in biology. Sample sizes of 500 or 1000 are difficult to achieve. However, use of this MA method may be a reasonable option when the researcher deals with problems which are intractable by other means. Copyright 1999 Academic Press.

Myelodysplastic syndrome with erythroid hypoplasia/aplasia: a case report and review of the literature

Myelodysplastic syndrome (MDS) with erythroid hypoplasia/aplasia has not yet been clearly defined, and in most patients it is mistaken for acquired pure red cell aplasia (PRCA). We report a patient with severe transfusion-dependent anemia (Hb 6.9 g/dl) and reticulocytopenia. WBC and platelet counts were normal. Bone marrow examination showed a marked trilineage dysplasia and a low percentage of erythroid precursors (3%). A diagnosis of MDS (refractory anemia according to FAB classification) with erythroid hypoplasia/aplasia was made. Repeated cytogenetic analysis of bone marrow showed normal karyotypes. Moreover, serial IgM serology and DNA analysis of the patient's sera for B19 parvovirus were negative. Other conditions known to be associated with erythroid aplasia were also absent. The patient failed hematinics and prednisone therapy. He next received r-HuEPO (200 U/kg three times weekly). This form of therapy achieved a rapid and complete erythroid response. He has remained in complete erythroid response after a 7-month period on maintenance therapy of 100 U/kg three times weekly. A review of the literature revealed only 15 well-documented cases of MDS with erythroid hypoplasia/aplasia. All had morphological evidence of myelodysplasia. These patients were predominantly elderly males, all required regular packed red cell transfusions, and had an unfavorable prognosis, mainly because of a high rate of blastic transformation (frequently preceded by a myeloproliferative phase). The mechanism of erythroid hypoplasia in this subgroup of MDS remains uncertain. However, laboratory and clinical data suggest the existence of an intrinsic stem cell defect. None of the patients received hematopoietic growth factors. To our knowledge, our patient is the first case of MDS with erythroid hypoplasia where r-HuEPO was successfully attempted. The description of more cases is necessary to delineate the value of r-HuEPO therapy in this rare variant of MDS.