Portrait of the Patient as a Young Man: An Exploration of the Use of Photographs in Hospital

The display of personal photographs in hospital is a common practice that has yet to be rigorously examined. The photographs displayed are subject to interpretation by the viewer and may lead to misunderstandings or miscommunication if clarification of meaning is not sought. This paper explores a range of possible meanings that the display of photographs in hospital may hold, based on a case study of a 15 year old boy hospitalised with a life threatening illness. Further research is needed into the actual meanings attributed to the display of photographs in hospital by patients and family members.     

Introducing the Multivariate Dale Model in Population‐Based Genetic Association Studies

Until recently, the most common parametric approaches to study the combined effects of several genetic polymorphisms located within a gene or in a small genomic region are, at the genotype level, logistic regressions and at the haplotype level, haplotype analyses. An alternative modeling approach, based on the case/control principle, is to regard exposures (e.g., genetic data such as derived from Single Nucleotide Polymorphisms – SNPs) as random and disease status as fixed and to use a marginal multivariate model that accounts for inter‐relationships between exposures. One such model is the multivariate Dale model. This model is based on multiple logistic regressions. That is why the model, applied in a case/control setting, leads to straightforward interpretations that are similar to those drawn in a classical logistic modeling framework. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Natural mortality at different population densities of a pine shoot moth,Evetria cristata

A field population of Evetria cristata was studied in 10 plots in 1962 and in 6 plots in 1963. These plots were divided into 2 or 3 groups of different population levels of the shoot moth in respective years. The survival of the insect was then analysed in these different groups of plots. The survival rate of E. cristata from eggs to adults in the first generation was found always higher in the group with low population density, which indicates the existence of some factors that affect the population more severely when the insect is more abundant. Lissonota evetriae and Pediobius sp. seemed to have killed more proportion of the hosts where the shoot moth density was high. However, the total effect of the all natural enemies was not always great in the plots with high density of the moth. The survival of the second generation of the moth in 1963 was observed to be much higher at any population level than in the other generations.     

Enhancement of acetaldehyde-protein adduct formation by L-ascorbate

The effect of L-ascorbate on the binding of [14C]acetaldehyde to bovine serum albumin was examined. In the absence of ascorbate, acetaldehyde reacted with albumin to form both unstable (Schiff bases) and stable adducts. Ascorbate (5 mM) caused a time-dependent increase in the formation of total acetaldehyde-albumin adducts, which were comprised mainly of stable adducts. Significant enhancement of adduct formation by ascorbate was observed at acetaldehyde concentrations as low as 5 microM. An ascorbate concentration as low as 0.5 mM was still effective in stimulating stable adduct formation. The electron acceptor, 2,6 dichlorophenolindophenol, prevented the ascorbate-induced increase in albumin-adduct formation. Ascorbate also caused enhanced acetaldehyde adduct formation with other purified proteins, including cytochrome c and histones, as well as the polyamino acid, poly-L-lysine. These results indicate that ascorbate, acting as a reducing agent, can convert unstable acetaldehyde adducts to stable adducts, and can thereby increase and stabilize the binding of acetaldehyde to proteins.     

Kinetics of the cooperativity of the Ca2+-transporting adenosine triphosphatase of sarcoplasmic reticulum and the mechanism of the ATP interaction.

The extent of the negative cooperativity with MgATP of the Ca²⁺-stimulated ATPase activity of sarcoplasmic reticulum has been studied with various membrane preparations and under various conditions. Preparations studied were fragmented sarcoplasmic reticulum vesicles, deoxycholate-solubilized and fractionated ATPase, triton extracted reticulum, vesicles reconstituted from either detergent, and limited trypsin digests of the reticulum. Conditions studied were suboptimal, optimal, and inhibitory Ca²⁺ concentrations; temperatures from 13 to 46 °C; 1 or 5 mm MgCl₂; 0.1 m KCl, 0.1 m NaCl, or no added salt; and Triton or deoxycholate present in the assay. With preparations in which vesicles could accumulate Ca²⁺ ion, the ionophore A23187 was added to prevent inhibition by internal Ca²⁺ ions. Under all circumstances, the negative cooperativity of MgATP was present (Hill coefficient of 0.2 to 0.8), indicating the persistence of the properties of the enzyme molecule and its lipid environment giving rise to kinetic negative cooperativity. Attempts to measure the number of ATP sites by protection against N-ethylmaleimide inactivation and by binding of an analog suggested, but did not prove, that there was only one specific, active ATP binding site below 0.5 mm. These results are interpreted to be consistent with either of two mechanisms for ATP cooperativity of the Ca²⁺-stimulated ATPase activity of sarcoplasmic reticulum: (a) a single, high affinity ATP active site and a second, lower affinity “allosteric” activator site; or (b) a single ATP site which demonstrates two affinities through some kinetic mechanism such as a substrate-induced, slow transition.     

Preparation, characterization, and functions of rabbit lymph node populations. III. Antigen-induced uptake of thymidine and dibutyryl cyclic AMP: inhibition of thymidine uptake by cholera toxin and dibutyryl cyclic AMP.

Keyhole limpet hemocyanin (KLH)-primed lymph node cell (LNC) populations were incubated with various amounts of KLH and the cellular incorporation of tritiated thymidine ([³H]TdR) or tritiated N⁶, O^2′ dibutyryl cyclic AMP ([³H]DbcAMP) was determined. T LNC responded more vigorously than did complement receptor lymphocytes (CRL), i.e., B cells, at all KLH concentrations, during all time intervals examined, and in the presence or absence of normal rabbit serum (NRS). The depletion of adherent cells from KLH-primed LNC resulted in no significant decrease in KLH-induced incorporation of either [³H]TdR or [³H]DbcAMP in any of the LNC populations. Thus it appeared that variation among LNC populations in the incidence of macrophages did not account for the marked variation in their responses. Cultures containing equal numbers of T and CRL were induced to incorporate more [³H]TdR or [³H]DbcAMP than either population cultured separately or the sum of their individual responses. It was concluded that KLH-induced incorporation of these substances into primed, isolated LNC, was primarily manifested in the T-cell population. The synergism seen in cultures containing mixtures of T and CRL suggested that B cells are induced to incorporate [³H]TdR or [³H]DbcAMP in the presence of antigen and T-cell product(s). KLH-induced incorporation of [³H]TdR into KLH-primed LNC was inhibited by cholera enterotoxin (CT) and DbcAMP as previously reported. However, CT or DbcAMP inhibited this incorporation into T LNC to a greater extent than into CRL or unfractionated LNC.     

Ozone effects on plants in natural ecosystems

Tropospheric ozone (O₃) is an important stressor in natural ecosystems, with well‐documented impacts on soils, biota and ecological processes. The effects of O₃ on individual plants and processes scale up through the ecosystem through effects on carbon, nutrient and hydrologic dynamics. Ozone effects on individual species and their associated microflora and fauna cascade through the ecosystem to the landscape level. Systematic injury surveys demonstrate that foliar injury occurs on sensitive species throughout the globe. However, deleterious impacts on plant carbon, water and nutrient balance can also occur without visible injury. Because sensitivity to O₃ may follow coarse physiognomic plant classes (in general, herbaceous crops are more sensitive than deciduous woody plants, grasses and conifers), the task still remains to use stomatal O₃ uptake to assess class and species’ sensitivity. Investigations of the radial growth of mature trees, in combination with data from many controlled studies with seedlings, suggest that ambient O₃ reduces growth of mature trees in some locations. Models based on tree physiology and forest stand dynamics suggest that modest effects of O₃ on growth may accumulate over time, other stresses (prolonged drought, excess nitrogen deposition) may exacerbate the direct effects of O₃ on tree growth, and competitive interactions among species may be altered. Ozone exposure over decades may be altering the species composition of forests currently, and as fossil fuel combustion products generate more O₃ than deteriorates in the atmosphere, into the future as well.     

Body site‐specific genetic effects influence naevus count distribution in women

Body site is highly relevant for melanoma: it affects prognosis and varies according to the patient's sex. The distribution of naevi, a major risk factor for melanoma, at different body sites also varies according to sex in childhood. Using naevus counts at different body sites in 492 unrelated adults from both sexes, we observed that women have an increased number of naevi on the lower limbs compared to men (p = 8.5 × 10^?5), showing that a high naevus count on this site persists from childhood throughout life. Then, using data from 3,232 twins, we observed, in women, the lowest naevus count heritability on the trunk (26%), and the highest on the lower limbs (69%). Finally, we showed that, in 2,864 women, six genomic loci previously associated with both naevus count and melanoma risk (IRF4, DOCK8, MTAP, 9q31.2, KITLG and PLA2G6) have an effect on naevus count that is body site‐specific, but whose effect sizes are predominantly stronger on the lower limbs. Sex‐specific genetic influence on naevus count at different sites may explain differences in site‐specific melanoma incidence as well as prognosis between sexes.     

An analytical study of the factors that influence COVID-19 spread

The outbreak of the coronavirus disease 2019 (COVID-19) continues to constitute an international public health emergency. Seasonality is a long-recognized attribute of many viral infections of humans. Nevertheless, the relationship between environmental factors and the spread of infection, particularly for person-to-person communicable diseases, remains poorly understood. This study explores the relationship between environmental factors and the incidence of COVID-19 in 188 countries with reported COVID-19 cases as of April 13, 2020. Here we show that COVID-19 growth rates peaked in temperate zones in the Northern Hemisphere during the outbreak period, while they were lower in tropical zones. The relationships between COVID-19 and environmental factors were resistant to the potentially confounding effects of air pollution, sea level, and population. To prove the effect of those factors, study, and analysis of the prevalence of COVID-19 in Italy, Spain, and China was undertaken. A fuzzy logic system was designed to predict the effects of that variables on the rate of viral spread of COVID-19.     

Clinical considerations in study designs that use cotinine as a biomarker

Subjects enrolled in studies are not always screened for routine habits such as smoking. Personal history is not always reliable and therefore an objective biomarker is necessary to screen for smokers. The objectives of this article were to review the metabolism of nicotine and other metabolic considerations associated with smoking; to review some of the routine methods used to assess exposure to nicotine-containing products; to revisit cotinine breakpoints utilized to distinguish smokers from non-smokers during screening for clinical trials; to assess the utility of screening questions regarding smoking practices; and to recommend standards for clinical pharmacology studies. The results indicated that cotinine levels serve as a useful biomarker of tobacco exposure; racial issues may be clinically relevant in determining smoking status; cessation of smoking should occur at least 14 days prior to the start of the study; adverse effects from nicotine withdrawal such as craving, hunger and weight gain may persist for more than 6 months; potential metabolic interactions via cytochrome P2A6 and P1A2 need to be considered when designing a study; and the use of a single calibrator as a breakpoint is acceptable if a categorical outcome such as 'smoker' versus 'non-smoker' is desired. Nicotine from food products is not expected to impact assay sensitivity or to be clinically relevant; a serum cotinine concentration of 10 ng ml^?1 be employed as a breakpoint for non-smokers versus smokers; other non-invasive alternatives are collection of urine, saliva, or hair (with suggested breakpoints of 200 ng ml^?1, 5 ng ml^?1 and 0.3 ng mg^?1, respectively; screening questions be accompanied by testing for cotinine; and the inclusion of smokers in studies should be considered once the impact of smoking on the targeted population is understood.