Association of late gadolinium enhancement in cardiac magnetic resonance with heart failure outcomes in patients with non-ischemic cardiomyopathy

Background

Late-gadolinium enhancement (LGE) in cardiac magnetic resonance (CMR) has been found to be associated with increased mortality in patients with non-ischemic cardiomyopathy (NICM). The correlation between LGE and heart failure (HF) hospitalization, referral for heart transplant, and ejection fraction (EF) improvement have not been well established.

Purpose

This meta-analysis assessed the relationship between LGE in CMR with HF hospitalization, referral for heart transplant and EF improvement in patients with NICM.

Methods

We searched the databases for studies reporting the association between LGE in CMR for NICM and HF outcomes including Ovid MEDLINE, EMBASE, Web of Science, and Google Scholar for all studies. The search was not restricted to time or publication status. The minimal follow up duration is one year.

Results

A total of 216 studies resulted from the literature search. A total of 25 studies and 3,039 patients (1,265 with LGE vs 1,774 without LGE) were included; mean follow up is around 33 months (ranging between 13 to 71 months). Our analysis demonstrated that LGE in NICM was associated with increased risk of HF hospitalization (odds ratio 3.38, 95% confidence interval 2.27–5.04; P<0.01), referral for transplant (odds ratio 5.08, 95% confidence interval 2.49–10.35; P<0.01), and lower chance for EF improvement (odds ratio 0.16, 95% confidence interval 0.03–0.85; P 0.03). Heterogeneity is moderate: χ2=49.5, df=21 (P=0.001), I2=57%. (Figures 1 and 2)

Conclusions

Our results suggest that LGE is associated with increased risk of HF hospitalization and referral for heart transplant and lower chance for EF improvement in long-term follow up.

Funding Acknowledgement

Type of funding sources: None.

Review of primary and secondary erythromelalgia

Erythromelalgia is a condition characterized by episodic pain, erythema and temperature of the extremities, which is relieved by cooling and aggravated by warming. It is useful to review this topic in light of recent discoveries of the genetic mutations that now define primary erythromelalgia, as opposed to secondary erythromelalgia, which is often associated with underlying medical disorders.

Probing chirality fluctuations in molecules by nonlinear optical spectroscopy

Symmetry breaking caused by geometric fluctuations can enable processes that are otherwise forbidden. An example is a perylene bisimide dyad whose dipole moments are perpendicular to each other. Förster-type energy transfer is thus forbidden at the equilibrium geometry since the dipolar coupling vanishes. Yet, fluctuations of the geometric arrangement have been shown to induce finite energy transfer that depends on the dipole variance, rather than the mean. We demonstrate an analogous effect associated with chirality symmetry breaking. In its equilibrium geometry, this dimer is non-chiral. The linear chiral response which depends on the average geometry thus vanishes. However, we show that certain 2D chiral optical signals are finite due to geometric fluctuations. Furthermore, the correlation time of these fluctuations can be experimentally revealed by the waiting time dependence of the 2D signal.

A safety audit of the first 10 000 intravitreal ranibizumab injections performed by nurse practitioners

PURPOSE

To evaluate the safety of a nurse practitioner (NP)-delivered injection service for the treatment of wet age-related macular degeneration (wAMD) with ranibizumab.

METHODS

An evaluation of medical staffing resources for providing an injection service for wAMD highlighted difficulties covering lists. An alternative strategy of an NP-delivered injection service was evaluated. Two suitable NPs with previous extensive experience in minor surgical procedures were identified. The department's senior vitreo-retinal consultant supervised the NP's training programme. A prospective safety audit was conducted for the first 5.5 years of the service.

RESULTS

The NPs administered 10 006 injections in the first 5.5 years of the service (1 May 2008 to 8 October 2013). This represented 84.1% of the total injections performed during this period. Four patients developed presumed infectious endophthalmitis (1 was culture positive and 3 were culture negative). The incidence of post-injection endophthalmitis was 0.04%. There was no evidence of lens touch, retinal detachment, or systemic thrombo-embolic events.

CONCLUSIONS

Carefully selected and well-trained NPs are capable of delivering a safe and effective wAMD injection treatment service. This work demonstrates how such a service can be established and provides safety data that other units can use as a benchmark when evaluating their own practice.

Human evolution and diet: a modern conundrum of health versus meat consumption, or is it?

Despite negative press reports on the effect of meat and other animal-source foods (ASFs) on human health and a vocal minority who contend that humans evolved as vegetarians, scientific evidence contradicts these views. For several million years before the development of agriculture, our ancestors were heavily reliant on ASFs as a source of energy and critical substrates such as protein and long-chain omega-3 fatty acids. Numerous lines of evidence in the anthropological literature have confirmed this scenario. Studies on ASF composition and clinical trials on ASF consumption have provided clear evidence of a requirement for meat in the diet to provide nutrients essential to health, such as Vitamin B12, long-chain omega-3 fatty acids and bioavailable forms of iron and zinc. Other studies have demonstrated that lean ASFs have a role in cholesterol-lowering diets and are important for mental function. Finally, it is possible and desirable to produce meat of a lean nature that mimics the many healthy attributes of wild-game meats and, by emphasising pasture feeding over grain feeding, this can be achieved to a large extent in Australia.

Modafinil treatment of amphetamine abuse in adult ADHD

Substance abuse is a frequent co-morbid condition of adult attention deficit hyperactivity disorder (ADHD). Treatment with conventional psychostimulants in adult ADHD with co-morbid stimulant abuse may be problematic. In this study, we report the case of a patient with adult ADHD with co-morbid amphetamine abuse who was treated successfully with the non-stimulant alertness-promoting drug modafinil. The drug resolved both the inattention/hyperactivity symptoms as well as the amphetamine abuse. Modafinil may be a suitable candidate treatment for adults with ADHD and stimulant abuse.

Identification of Lps2 as a key transducer of MyD88-independent TIR signalling

In humans, ten Toll-like receptor (TLR) paralogues sense molecular components of microbes, initiating the production of cytokine mediators that create the inflammatory response. Using N-ethyl-N-nitrosourea, we induced a germline mutation called Lps2, which abolishes cytokine responses to double-stranded RNA and severely impairs responses to the endotoxin lipopolysaccharide (LPS), indicating that TLR3 and TLR4 might share a specific, proximal transducer. Here we identify the Lps2 mutation: a distal frameshift error in a Toll/interleukin-1 receptor/resistance (TIR) adaptor protein known as Trif or Ticam-1. Trif(Lps2) homozygotes are markedly resistant to the toxic effects of LPS, and are hypersusceptible to mouse cytomegalovirus, failing to produce type I interferons when infected. Compound homozygosity for mutations at Trif and MyD88 (a cytoplasmic TIR-domain-containing adaptor protein) loci ablates all responses to LPS, indicating that only two signalling pathways emanate from the LPS receptor. However, a Trif-independent cell population is detectable when Trif(Lps2) mutant macrophages are stimulated with LPS. This reveals that an alternative MyD88-dependent 'adaptor X' pathway is present in some, but not all, macrophages, and implies afferent immune specialization.

The paradoxical nature of hunter-gatherer diets: meat-based, yet non-atherogenic

OBJECTIVE

Field studies of twentieth century hunter-gathers (HG) showed them to be generally free of the signs and symptoms of cardiovascular disease (CVD). Consequently, the characterization of HG diets may have important implications in designing therapeutic diets that reduce the risk for CVD in Westernized societies. Based upon limited ethnographic data (n=58 HG societies) and a single quantitative dietary study, it has been commonly inferred that gathered plant foods provided the dominant energy source in HG diets.

METHOD AND RESULTS

In this review we have analyzed the 13 known quantitative dietary studies of HG and demonstrate that animal food actually provided the dominant (65%) energy source, while gathered plant foods comprised the remainder (35%). This data is consistent with a more recent, comprehensive review of the entire ethnographic data (n=229 HG societies) that showed the mean subsistence dependence upon gathered plant foods was 32%, whereas it was 68% for animal foods. Other evidence, including isotopic analyses of Paleolithic hominid collagen tissue, reductions in hominid gut size, low activity levels of certain enzymes, and optimal foraging data all point toward a long history of meat-based diets in our species. Because increasing meat consumption in Western diets is frequently associated with increased risk for CVD mortality, it is seemingly paradoxical that HG societies, who consume the majority of their energy from animal food, have been shown to be relatively free of the signs and symptoms of CVD.

CONCLUSION

The high reliance upon animal-based foods would not have necessarily elicited unfavorable blood lipid profiles because of the hypolipidemic effects of high dietary protein (19-35% energy) and the relatively low level of dietary carbohydrate (22-40% energy). Although fat intake (28-58% energy) would have been similar to or higher than that found in Western diets, it is likely that important qualitative differences in fat intake, including relatively high levels of MUFA and PUFA and a lower omega-6/omega-3 fatty acid ratio, would have served to inhibit the development of CVD. Other dietary characteristics including high intakes of antioxidants, fiber, vitamins and phytochemicals along with a low salt intake may have operated synergistically with lifestyle characteristics (more exercise, less stress and no smoking) to further deter the development of CVD.

Auxiliary functions in photosynthesis: the role of the FtsH protease

Oxygenic photosynthesis can be described effectively by using two long-standing models: the Z-scheme and the chemiosmotic hypothesis. However, these models do not reveal the dynamic nature of the thylakoid membrane and the four major complexes that it binds. The composition of the photosynthetic apparatus is continually changing in response to a range of environmental stimuli. In addition, many photosynthetic components have some of the highest turnover rates in Nature. Changes in composition and turnover of photosynthetic components require the degradation of existing and damaged polypeptides and the resynthesis and co-ordinated assembly of new polypeptides and their associated cofactors. This is achieved by several auxiliary functions, including proteolysis, protein targeting and the action of molecular chaperones. Some of the components involved in these functions, such as translocons, chaperones and proteases, have been identified but many of the auxiliary functions of photosynthesis remain uncharacterized. Among the proteases known to be associated with the thylakoids is the zinc metalloprotease FtsH, which might also act as a chaperone. Here we provide an overview of the thylakoid FtsH protease and discuss its role in the maintenance and assembly of the photosynthetic apparatus.

Recombinant expression analysis of natural and synthetic bovine alpha-casein in Escherichia coli

As a prelude to developing a yeast-based fermentation process for the production of phenylalanine-free alpha-casein as a foodstuff for patients suffering from phenylketonuria, we cloned the gene encoding bovine alpha-casein. We synthesised a modified gene sequence encoding the same, but devoid of phenylalanine codons and with a codon bias similar to that of naturally occurring highly expressed genes in Saccharomyces cerevisiae. The results show that both gene sequences are readily expressed in Escherichia coli when cloned in an E. coli bacteriophage T7 promoter-driven plasmid vector. In this host, the natural and synthetic casein proteins were produced at levels equating to 18.0% and 7.6% of the cell's soluble protein, respectively.

Functional independence measure prediction: an initial evaluation of residents' skills

The purpose of this preliminary study was to assess the ability of first-year PM&R residents to accurately predict functional outcome in an acute rehabilitation setting. Although statistically significant, the accuracy and precision of the residents' predictive skills were rather modest. A future focus on innovative methods to evaluate and develop these clinical skills appears warranted.

Dietary lean red meat and human evolution

Scientific evidence is accumulating that meat itself is not a risk factor for Western lifestyle diseases such as cardiovascular disease, but rather the risk stems from the excessive fat and particularly saturated fat associated with the meat of modern domesticated animals. In our own studies, we have shown evidence that diets high in lean red meat can actually lower plasma cholesterol, contribute significantly to tissue omega-3 fatty acid and provide a good source of iron, zinc and vitamin B12. A study of human and pre-human diet history shows that for a period of at least 2 million years the human ancestral line had been consuming increasing quantities of meat. During that time, evolutionary selection was in action, adapting our genetic make up and hence our physiological features to a diet high in lean meat. This meat was wild game meat, low in total and saturated fat and relatively rich in polyunsaturated fatty acids (PUFA). The evidence presented in this review looks at various lines of study which indicate the reliance on meat intake as a major energy source by pre-agricultural humans. The distinct fields briefly reviewed include: fossil isotope studies, human gut morphology, human encephalisation and energy requirements, optimal foraging theory, insulin resistance and studies on hunter-gatherer societies. In conclusion, lean meat is a healthy and beneficial component of any well-balanced diet as long as it is fat trimmed and consumed as part of a varied diet.

Plant-animal subsistence ratios and macronutrient energy estimations in worldwide hunter-gatherer diets

Both anthropologists and nutritionists have long recognized that the diets of modern-day hunter-gatherers may represent a reference standard for modern human nutrition and a model for defense against certain diseases of affluence. Because the hunter-gatherer way of life is now probably extinct in its purely un-Westernized form, nutritionists and anthropologists must rely on indirect procedures to reconstruct the traditional diet of preagricultural humans. In this analysis, we incorporate the most recent ethnographic compilation of plant-to-animal economic subsistence patterns of hunter-gatherers to estimate likely dietary macronutrient intakes (% of energy) for environmentally diverse hunter-gatherer populations. Furthermore, we show how differences in the percentage of body fat in prey animals would alter protein intakes in hunter-gatherers and how a maximal protein ceiling influences the selection of other macronutrients. Our analysis showed that whenever and wherever it was ecologically possible, hunter-gatherers consumed high amounts (45-65% of energy) of animal food. Most (73%) of the worldwide hunter-gatherer societies derived >50% (> or =56-65% of energy) of their subsistence from animal foods, whereas only 14% of these societies derived >50% (> or =56-65% of energy) of their subsistence from gathered plant foods. This high reliance on animal-based foods coupled with the relatively low carbohydrate content of wild plant foods produces universally characteristic macronutrient consumption ratios in which protein is elevated (19-35% of energy) at the expense of carbohydrates (22-40% of energy).

Sitting balance following brain injury: does it predict outcome?

Balance dysfunction is commonly observed following traumatic brain injury. There are many proposed predictors of functional outcome in the traumatic brain injury population. It was hypothesized that the degree of balance dysfunction on admission to rehabilitation would be a significant predictor of the need for assistance at discharge, as measured by the Functional Independence Measure (FIM). This study involved 237 cases of traumatic brain injury patients admitted to a rehabilitation unit between November 1989 and September 1996. Using a multiple regression model, controlling for age, initial Glasgow Coma Score (GCS), rehabilitation admission strength, sitting balance and standing balance, it was found that the degree of impairment in sitting balance at admission to rehabilitation was a significant predictor of Discharge FIM-Total (FIM-T) score (p < 0.0001) and also of selected elements from the Discharge FIM-Motor (FIM-M) score (p < 0.0005). The combination of age, initial admission GCS, rehabilitation admission strength, standing balance and sitting balance accounted for 29% of the variance in the Discharge Total FIM score. Among these, sitting balance was the second most powerful predictor of both selected elements of the Discharge FIM motor score and discharge FIM-T. Sitting balance predictive capacity was exceeded in power only by age. Impairments in sitting balance appear to have a significant impact on functional outcome. Emphasis on unique rehabilitation techniques to treat balance dysfunction in the adult TBI population is warranted.

The association of diet and thrombotic risk factors in healthy male vegetarians and meat-eaters

OBJECTIVE

The aim of this study was to assess thrombosis tendency in subjects who were habitual meat-eaters compared with those who were habitual vegetarians.

DESIGN

Cross-sectional comparison of habitual meat-eaters and habitual vegetarians.

SETTING

Free living subjects.

SUBJECTS

One hundred and thirty-nine healthy male subjects (vegans n = 18, ovolacto vegetarians n = 43, moderate-meat-eaters n = 60 and high-meat-eaters n = 18) aged 20-55 y who were recruited in Melbourne.

OUTCOME MEASURES

Dietary intake was assessed using a semi-quantitative Food Frequency Questionnaire. The parameters of thrombosis were measured by standard methods.

RESULTS

Saturated fat and cholesterol intakes were significantly higher and polyunsaturated fat (PUFA) was significantly lower in the meat-eaters compared with vegetarians. In the meat-eaters, the platelet phospholipids AA levels were significantly higher than in the vegetarians, but there was no increase in ex vivo platelet aggregation and plasma 11-dehydro thromboxane B2 levels. Vegetarians, especially the vegans, had a significantly increased mean collagen and ADP stimulated ex vivo whole blood platelet aggregation compared with meat-eaters. The vegan group had a significantly higher mean platelet volume than the other three dietary groups. However, meat-eaters had a significantly higher cluster of cardiovascular risk factors compared with vegetarians, including increased body mass index, waist to hip ratio, plasma total cholesterol (TC), triacylglycerol and LDL-C levels, ratio of TC/HDL-C and LDL-C/HDL-C and plasma factor VII activity.

CONCLUSIONS

Consumption of meat is not associated with an increased platelet aggregation compared with vegetarian subjects.

Effect of dietary alpha-linolenic acid on thrombotic risk factors in vegetarian men

BACKGROUND

Vegetarians have lower platelet and plasma concentrations of n-3 polyunsaturated fatty acids (PUFAs) than do omnivores. We recently showed that male vegetarians have higher platelet aggregability than do omnivores.

OBJECTIVE

We investigated whether male vegetarians (n = 17) who consumed an increased amount of dietary alpha-linolenic acid (ALA) showed any changes in their tissue profile of PUFAs, plasma thromboxane concentrations, platelet aggregability, or hemostatic factors.

DESIGN

During the study, all subjects maintained their habitual vegetarian diets except that a proportion of dietary fat was replaced with vegetable oils and margarines that were provided. Initially, all subjects consumed a low-ALA diet (containing safflower oil and safflower oil-based margarine) for 14 d; they then consumed either a moderate-ALA diet (containing canola oil and canola oil-based margarine) or a high-ALA diet (containing linseed oil and linseed oil-based margarine) for 28 d. Blood samples were collected at day 0 (baseline), day 14, and day 42.

RESULTS

Eicosapentaenoic acid, docosapentaenoic acid, total n-3 PUFAs, and the ratio of n-3 to n-6 PUFAs were significantly increased (P < 0.05), whereas the ratio of arachidonic acid to eicosapentaenoic acid was decreased (P < 0.05), in platelet phospholipids, plasma phospholipids, and triacylglycerols after either the moderate-ALA or high-ALA diet compared with the low-ALA diet. No significant differences were observed in thrombotic risk factors.

CONCLUSION

ALA from vegetable oils (canola and linseed) has a beneficial effect on n-3 PUFA concentrations of platelet phospholipids and plasma lipids in vegetarian males.

Does the requirement of a craniotomy predict outcome? A preliminary investigation

The literature has been replete with reports that persons who require craniotomy for treatment of their traumatic brain injury have a far worse outcome. The majority of these reports have utilized the rather global Glasgow Outcome Scale as a determinant of outcome. This paper sought to evaluate the effect of craniotomy on outcome as measured by the DRS. Data was collected on 341 persons (mean age 37.7 years) with traumatic brain injury treated at the Level I trauma centre, who required inpatient rehabilitation. Surgical interventions were classified as 'no surgery', 'one cranial surgery', or 'two or more cranial surgeries'. Initial GCS scores revealed 44 persons at GCS 3-5, 102 persons at GCS 6-8, 83 persons at GCS 9-12 and 112 persons at GCS 13-15. The DRS was administered to each person at discharge from in-patient rehabilitation. Mean DRS scores were 7.07 for GCS 3-5, 6.03 for GCS 6-8, 6.53 for GCS 9-12, 5.57 for GCS 13-15 groups. A factorial ANOVA revealed an interaction between initial GCS and surgical status. Univariate ANOVA's demonstrated significant differences in the GCS 3-5 and GCS 13-15 groups, suggesting a relationship between need for surgical intervention and less favourable outcome among persons who required in-patient rehabilitation. However, no differences were demonstrated in the GCS 6-8 and GCS 9-12 groups. It appears that requiring surgical intervention is prognostic at only the extremes of the GCS categories and, thus, further investigation may reveal the limited role of need for surgical intervention injury in predicting outcome in persons with initial GCS 6-12.

Brain injury as a result of violence: preliminary findings from the traumatic brain injury model systems

OBJECTIVES

To identify possible risk factors that may predispose individuals to violent traumatic brain injury (TBI) and to determine the effect of etiology of injury on outcomes.

STUDY DESIGN

Prospective, longitudinal multicenter study.

SETTING

TBI Model Systems (TBIMS) located at Wayne State University/Rehabilitation Institute of Michigan, Detroit, MI; The Institute for Rehabilitation and Research, Houston, TX; Medical College of Virginia, Richmond, VA; and Santa Clara Valley Medical Center, San Jose, CA.

SUBJECTS

Individuals treated in the four TBIMS programs between 3/89 and 9/96 who met the criteria for inclusion in the TBIMS National Database and for whom the etiology was known (n=812).

MAIN OUTCOME MEASURES

Functional Independence Measure, Alcohol Quantity Frequency Variability Index, Community Integration Questionnaire.

RESULTS

Individuals who incur violence-related TBI tend to be male, nonwhite, unmarried, living alone, less educated, and unemployed at time of injury. They tend to have less severe brain injuries and better motor function at the time of admission to inpatient rehabilitation. At 1 year postinjury, they score lower on community integration measures; however, no difference exists in functional status. Etiology of injury was found to only play a minor role in the prediction of social and productive integration at 1 year postinjury.

CONCLUSIONS

Survivors of violent and nonviolent TBI have similar functional outcomes; however, they differ in preinjury and postinjury socio-economic characteristics, injury severity, and postinjury community integration. Socio-economic factors appear to play a large role in the risk for violent injury and in community integration following injury.

Transition metals as protease inhibitors

An alternative approach to the development of clinically useful protease inhibitors was investigated. The approach utilized coordination chemistry of transition metal ions rather than substrate analogs to block active sites of these enzymes. In the case of serine proteases it was found that aqueous Ti(IV) is a potent inhibitor of the trypsin subclass, but not the chymotrypsin subclass. The direct binding of Ti(IV) to trypsin was made possible by the presence of a free carboxyl group at the bottom of the substrate binding pocket of the enzyme, and the five-coordinate geometry of TiO(SO4)(H2O). Although initial binding of Ti(IV) was reversible, it was followed in time by irreversible inhibition. Direct binding of octahedral or tetrahedral metal ion complexes was prevented by the inability of the enzyme active sites to promote formation of a five-coordinate transition state of the metal ion required for reaction. These studies demonstrate the ability of direct metal ion binding as a way to enhance blocking of enzyme active sites as compared with that of traditional organic inhibitors. Application of these findings was investigated by measuring the affect Ti(IV) had on growth of Escherichia coli, Salmonella typhimurium, and Pseudomonas aeruginosa. Five-coordinate titanyl sulfate completely inhibited the growth of these organisms. This suggests that five-coordinate titanyl sulfate, which is easier and less expensive to manufacture than conventional antibiotics, may be useful in controlling endemic infections of E. coli and S. typhimurium.

Pulmonary agenesis: a predictor of ipsilateral malformations

Pulmonary agenesis is a rare malformation that can be isolated or associated with other anomalies. We became interested in pulmonary agenesis after evaluation of a child with right pulmonary agenesis, an unlobed left lung, bilateral cleft lip and palate, maxillary and mandibular hypoplasia, bilateral microtia, bilateral radial ray hypoplasia, horseshoe kidney, and complex congenital heart disease. A review of the occurrence of pulmonary agenesis with other congenital anomalies uncovered a striking association with ipsilateral radial ray defects and/or hemifacial microsomia. The presence of bilateral facial or radial ray anomalies was indicative of bilateral pulmonary involvement. A review of the cases of pulmonary agenesis and associated anomalies at the Children's Hospital and Medical Center confirmed the association of pulmonary agenesis and ipsilateral involvement of face and/or radial ray. The association of pulmonary agenesis and ipsilateral malformations may shed light on its pathogenesis. Although the cause of these associated anomalies remains unclear, abnormalities in the development of the aortic arches during embryogenesis is an attractive hypothesis.

Pulmonary agenesis: a predictor of ipsilateral malformations

Pulmonary agenesis is a rare malformation that can be isolated or associated with other anomalies. We became interested in pulmonary agenesis after evaluation of a child with right pulmonary agenesis, an unlobed left lung, bilateral cleft lip and palate, maxillary and mandibular hypoplasia, bilateral microtia, bilateral radial ray hypoplasia, horseshoe kidney, and complex congenital heart disease. A review of the occurrence of pulmonary agenesis with other congenital anomalies uncovered a striking association with ipsilateral radial ray defects and/or hemifacial microsomia. The presence of bilateral facial or radial ray anomalies was indicative of bilateral pulmonary involvement. A review of the cases of pulmonary agenesis and associated anomalies at the Children's Hospital and Medical Center confirmed the association of pulmonary agenesis and ipsilateral involvement of face and/or radial ray. The association of pulmonary agenesis and ipsilateral malformations may shed light on its pathogenesis. Although the cause of these associated anomalies remains unclear, abnormalities in the development of the aortic arches during embryogenesis is an attractive hypothesis.

The effect of short-term diets rich in fish, red meat, or white meat on thromboxane and prostacyclin synthesis in humans

Foods which increase tissue arachidonic acid levels have been proposed to increase thrombosis tendency, presumably through increased platelet aggregation. This study examined the effect of doubling the dietary arachidonic acid (20:4n-6) using meat- or fish-based diets on the systemic production of prostacyclin (PGI2) and thromboxane (TXA2) in 29 healthy, nonsmoking adults. There were three, 3-wk low-fat dietary periods (< 15% energy as fat) in which subjects consumed a vegetarian diet for 1 wk followed by 2 wk on diets containing meat or fish as sources of 20:4n-6. Between each diet period, there was a 3-wk washout period, during which subjects returned to their normal diets. The level of 20:4n-6 consumed during the last 2 wk of each study was approximately double the usual intake (mean 140 mg/d), while the mean eicosapentaenoic acid (20:5n-3) content of the diets varied from 1 mg/d on the white meat diet to 70 mg/d on the red meat diet and to 847 mg/d on the fish diet. The serum phospholipid (PL) 20:4n-6/20:5n-3 ratios were 11:1 on the vegetarian diet, 15:1 on the white meat diet, 8:1 on the red meat diet, and 2:1 on the fish diet (P < 0.001). Neither white nor red meat diets affected platelet 20:4n-6 levels, platelet aggregation, ex vivo platelet TXB2 production, or the systemic PGI2 or TXA2 production as measured by gas chromatography-mass spectrometry analysis of the excretion levels of the principal urinary metabolites 2,3-dinor-6-keto-PGF1 alpha (PGI2-M) and 11-dehydro-TXB2 (TXA2-M), respectively. The fish diet decreased the 20:4n-6/20:5n-3 ratio in platelet PL from the baseline level of 45:1 to 13:1 (P < 0.001), had no effects on platelet aggregation, but significantly decreased platelet TXB2 production (collagen-stimulated) and TXA2-M production, while PGI2-M levels were unaltered. These results indicate that short-term diets which double the usual 20:4n-6 intake using white meat (175-330 g/d) or red meat (275-530 g/d) are not associated with an increased TXA2 production, but this does not rule out the adverse effects of 20:4n-6 at higher levels in the diet, or for more prolonged periods. Short-term diets containing fish (100-200 g/d with 90-210 mg/d 20:4n-6 and approximately 650-1000 mg/d 20:5n-3) led to significant increases in platelet 20:5n-3 levels and a decrease in the ex vivo and systemic TXA2 production.

Telecommunications role evolves beyond mere utility

A more regionalized healthcare delivery system has expanded the role of the telecommunications department. Applications such as teleradiology and telemedicine are making increasingly sophisticated demands on communications systems and their managers.

Engineered immunoglobulin molecules as vehicles for T cell epitopes

The variable regions (V) of immunoglobulins (Ig) bear antigenic determinants that can stimulate both humoral and cellular immune responses subsequent to hetero, allo or iso-immunization. The expression of these determinants by Igs usually correlates with the presence of specific amino acid residues within the CDR loops of the V regions. Since the CDR loops varies in length, we reasoned that they would represent permissive sites to insert foreign peptides and create antigenized Igs expressing selected determinants. Taking advantage of these properties and the fact that Igs are self and long-lived molecules, we expressed a CTL and a helper epitope of influenza virus nucleoprotein and hemagglutinin respectively, within the heavy chain CDR3 loop of an anti-arsonate antibody. We found that foreign peptides comprised of 11 to 15 amino acid residues can be expressed within the V region of the heavy chain without alteration of pairing with the light chain. More striking, the cellular processing machinery is able to generate the peptides from the Ig context which were then recognized by specific T cells. Furthermore, the engineered Igs are able to induce T cell responses specific for the inserted peptide and for influenza virus. The use of engineered Ig molecules as vehicles for T and B cell peptides might represent a valuable strategy to generate safe, long lived reagents able to stimulate strong specific immune responses. This would then overcome the short half life of synthetic peptides based vaccines and the side effects seen in case of recombinant viral proteins or inactivated viruses based vaccines.

Description and interobserver reliability of the Tufts Assessment of Motor Performance

This paper describes the conceptual basis for the development of a new clinical evaluation instrument, the Tufts Assessment of Motor Performance (TAMP). The TAMP is a 32-item, diagnosis-independent, criterion-referenced test that samples physical performance items in the areas of mobility, activities of daily living and physical aspects of communication. The administrative and scoring criteria of the TAMP are presented, and the multiple measurement dimensions are described. The documentation of patient status and progress, as described in the functional and performance profiles, is outlined. The paper also reports initial interobserver reliability on the intraitem tasks and the summary indexes of the two profiles. Forty individuals (20 adults and 20 children) with neurologic and musculoskeletal disorders comprised the reliability sample. Kappa and intraclass correlations were used to estimate the reliability of three independent raters on individual tasks and aggregate scores, respectively. Task reliability for the assistance and approach measurement dimensions were generally higher than for the more qualitative pattern and proficiency dimensions. Yet over 90% of all the tasks had acceptable reliability, while all the summary indexes had high interobserver reliability. Determination of interobserver reliability data is the initial phase of defining the most appropriate and technically valuable items, and will serve as a basis for item revision and reduction to enhance the clinical utility of the test.

Survey of computer-assisted electrocardiography in the United States

The purpose of this study was to update a 1976 study by Arthur D. Little, Inc., on the use of automatic ECG analysis systems. Thirteen vendors of computerized ECG systems received survey forms in 1987 and a follow-up telephone survey was completed in early 1988. The vendors surveyed included service bureaus and providers of computer-based data management and analysis systems and analysis carts. Analysis carts were subdivided into standard-sized and portable analysis carts. The technical specifications used by the respondents varied from 3 simultaneous leads to 14 simultaneous leads. The standards used were AHA, AAMI, and ANSI. Various compression techniques were used. The method of testing adult, pediatric, and serial comparison programs varied from the use of expert electrocardiographers to non-ECG data bases. Service bureau customers consisted mainly of general practitioners and primary care physicians' offices, with an estimated 1.2 million ECGs processed in 1987. Analysis and data management systems mainly serviced large hospitals, with an estimated 15 million ECGs processed in 1987. Standard-sized analysis carts used in hospitals and physicians' offices were estimated to process over 31 million ECGs in 1987. Portable analysis carts installed in hospitals, primary care, and general practitioners' offices and clinics processed almost 7 million ECGs in 1987. Computerized ECG analysis has been one of the most rapidly and widely adopted computer applications in medicine; its potential benefits in improving quality and consistency of interpretations has long been recognized. This study indicates that additional information on accuracy of current ECG software is needed to ensure that the technology is optimally applied in patient care.

The distribution of lung damage in children with cystic fibrosis and its relationship to colonisation with Pseudomonas aeruginosa

Ventilation-perfusion lung scans were performed with 81mKr inhalation and 99mTc-albumin injection in 33 children with cystic fibrosis. It was found that both ventilation and perfusion scans yielded more information than radiographs of the chest in assessing lung damage. Using a scoring system, it was demonstrated by statistical methods that in the worst affected patients the disease was worse in the upper zones of the lungs, which changes were not detectable on chest radiographs. Pseudomonas was present in the sputum of these patients.

The child health clinic: results of a new strategy of community care in a deprived area

Substantial changes were made in the organisation of a child health clinic serving an underprivileged population in Nottingham. A community paediatric team approach was adopted, routine medical checks were reduced, and referrals from elsewhere (including parents) were encouraged. The changes resulted in an older and more deprived population of preschool children being seen by the clinic doctors. More treatable medical disorders were detected with this approach.

Prevalence of morning hyperglycaemia: determinants of fasting blood glucose concentrations in insulin-treated diabetics

A rise in blood glucose concentration at the end of the night, and consequent morning hyperglycaemia, are well recognized events in some diabetic patients. In 94 patients on twice daily insulin injections we have examined the prevalence and extent of morning hyperglycaemia, and its relation to control, insulin therapy, and insulin antibody levels. Blood glucose reached the highest level of the day before or after breakfast in 83% of patients, and in 50% this value was 2 mmol/l greater than any other time of day. Patients with higher fasting concentrations did not have worse blood glucose control over the rest of the day. No correlation was found between fasting blood glucose concentrations and the evening dose of intermediate acting insulin or the level of insulin antibodies. No consistent change in fasting blood glucose concentrations occurred with changes in antibody levels in patients switched between pork and beef insulin. Morning hyperglycaemia was as common with both insulin species. Pre- and post-breakfast hyperglycaemia is common and significant in insulin-treated diabetic patients. It is not directly related to diabetic control at other times of the day, and is independent of insulin species and insulin antibody levels.

Ultrastructure of Nocardia-like variants of Mycobacterium smegmatis and chemical composition of the basal cell wall layer

Mycobacterium smegmatis, its orange-red--pigmented (OR) variants, and back mutant strains were examined by electron microscopy using ultrathin sectioning, negative or positive staining, and freeze-fracture-etching methods. The parental and back mutant strains showed almost identical ultrastructures. Specifically, thick ramified fibers measuring about 15 nm in diameter were always visible in the positively stained cell wall, although they were not readily visualized with negative staining or freeze-fracture-etching. In contrast, the cell walls of OR variants contained fibrous networks measuring about 11 nm in diameter, which could be observed by positive and negative staining as well as freeze-fracture-etching. Although cytoplasmic structures appeared similar among the four strains examined, mesosomes were significantly more abundant in the OR variants. The basal layer of the cell wall obtained as a phenol residue consisted of a dense membranous matrix containing scattered fibrous structures in the parental and back mutant strains, and fibrous networks in the OR variants. Chemical analyses showed that the basal layers of all four strains contained the same neutral sugars, amino sugars, and amino acids, i.e., arabinose, galactose, muramic acid, glucosamine, alanine, glutamic acid, and diaminopimelic acid. The alpha-branched, beta-hydroxylated fatty acids contained in the basal layers differ among the four strains, however, with nocardomycolic acids being present in the OR variants and mycolic acids in the parental and back mutant strains. Our previous conclusion that OR variants of M. smegmatis have characteristics similar to those of nocardia is supported by the present study.

Coupling between the initiation of DNA replication and cell division in the blue-green alga Anacystis nidulans

The effect of mitomycin C on cell mass increase, cell division, RNA synthesis and DNA synthesis in the blue-green alga Anacystis nidulans has been examined. Data suggests that the initiation of DNA replication, rather than its termination was the necessary event for cell division to occur.

Isolation and characterization of nocardia-like variants of Mycobacterium smegmatis

Orange-red-pigmented (OR) colonies were isolated from cream-yellow-pigmented Mycobacterium smegmatis after exposure to either mycobacteriophage MC4 or ultraviolet light; these variant strains were designated OR4 and ORuv, respectively. Early subculture of OR-colonies did not show any segregation of parental-type cells. However, colonies resembling the parental strains, possibly representing a back mutant (REV-OR4), were occasionally found during subculture of established OR-colonies or upon treatment with N-nitrose-N'-nitro-N-methylguanidine. The OR-variants were characterized by their lytic response to nocardiophage, but not to mycobacteriophages, presence of alpha-branched, beta-hydroxylated fatty acids of the Nocardia-type, and a guanine plus cytosine value of deoxyribonucleic acid (DNA) between 62 and 64 mol%. They were more resistant to the lethal action of both ultraviolet light and mitomycin C treatment than the parental and back mutant strains. Although the OR-variants in this study possess characteristics common to the genus Nocardia or some of the 'rhodochrous' mycobacteria, evidence is presented that they form a new class of mycobacterial variants.