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Plasmodium vivax lactate dehydrogenase (PvLDH) is an essential enzyme in the glycolytic pathway of P. vivax. It is widely used as a diagnostic biomarker and a measure of total-body parasite biomass in vivax malaria. However, the dynamics of PvLDH remains poorly understood. Here, we developed mathematical models that capture parasite and matrix PvLDH dynamics in ex vivo culture and the human host. We estimated key biological parameters characterising in vivo PvLDH dynamics based on longitudinal data of parasitemia and PvLDH concentration collected from P. vivax-infected humans, with the estimates informed by the ex vivo data as prior knowledge in a Bayesian hierarchical framework. We found that the in vivo accumulation rate of intraerythrocytic PvLDH peaks at 10–20 h post-invasion (late ring stage) with a median estimate of intraerythrocytic PvLDH mass at the end of the life cycle to be 9.4 × 10−3ng. We also found that the median estimate of in vivo PvLDH half-life was approximately 21.9 h. Our findings provide a foundation with which to advance our quantitative understanding of P. vivax biology and will facilitate the improvement of PvLDH-based diagnostic tools. A modelling framework characterising the dynamics of Plasmodium vivax lactate dehydrogenase provides estimates of key biological parameters to facilitate the development of improved diagnostic tools for the detection of P. vivax. [ABSTRACT FROM AUTHOR]

Atmospheric rivers (ARs) generate most of the economic losses associated with flooding in the western United States and are projected to increase in intensity with climate change. This is of concern as flood damages have been shown to increase exponentially with AR intensity. To assess how AR-related flood damages are likely to respond to climate change, we constructed county-level damage models for the western 11 conterminous states using 40 years of flood insurance data linked to characteristics of ARs at landfall. Damage functions were applied to 14 CMIP5 global climate models under the RCP4.5 "intermediate emissions" and RCP8.5 "high emissions" scenarios, under the assumption that spatial patterns of exposure, vulnerability, and flood protection remain constant at present day levels. The models predict that annual expected AR-related flood damages in the western United States could increase from $1 billion in the historical period to $2.3 billion in the 2090s under the RCP4.5 scenario or to $3.2 billion under the RCP8.5 scenario. County-level projections were developed to identify counties at greatest risk, allowing policymakers to target efforts to increase resilience to climate change. [ABSTRACT FROM AUTHOR]

Commercial point-of-care tests remain insufficient for accurately detecting and differentiating low-level malaria infections in regions co-endemic with multiple non-falciparum species, including zoonotic Plasmodium knowlesi (Pk). A 5-plex chemiluminescent assay simultaneously measures pan-Plasmodium lactate dehydrogenase (pLDH), P. falciparum (Pf)-LDH, P. vivax (Pv)-LDH, Pf-histidine-rich protein-2 (HRP2), and C-reactive protein. We assessed its diagnostic performance on whole blood (WB) samples from 102 healthy controls and 306 PCR-confirmed clinical cases of Pf, Pv, Pk, P. malariae (Pm) and P. ovale (Po) mono-infections from Southeast-Asia. We confirm its excellent HRP2-based detection of Pf. Cross-reactivity of Pf-LDH with all non-falciparum species tested was observed (specificity 57.3%). Pv-LDH performance was suboptimal for Pv (93.9% sensitivity and 73.9% specificity). Poor specificity was driven by strong Pk cross-reactivity, with Pv-LDH detecting 93.9% of Pk infections. The pan-LDH-to-Pf-LDH ratio was capable of discerning Pv from Pk, and robustly differentiated Pf from Pm or Po infection, useful in regions with hrp2/3 deletions. We tested the platform's performance in plasma for the first time, with WB outperforming plasma for all analytes except Pv-LDH for Pk. The platform is a promising tool for WB malaria diagnosis, although further development is warranted to improve its utility in regions co-endemic for multiple non-falciparum species. [ABSTRACT FROM AUTHOR]

Cerebral malaria is the most serious manifestation of severe falciparum malaria. Sequestration of infected red blood cells and microvascular dysfunction are key contributing processes. Whether these processes occur in early stage disease prior to clinical manifestations is unknown. To help localize and understand these processes during the early stages of infection, we performed 18-F fluorodeoxyglucose positron emission tomography/magnetic resonance imaging in volunteers with Plasmodium falciparum induced blood stage malaria (IBSM) infection, and compared results to individuals with P. vivax infection, in whom coma is rare. Seven healthy, malaria-naïve participants underwent imaging at baseline, and at early symptom onset a median 9 days following inoculation (n = 4 P. falciparum, n = 3 P. vivax). Participants with P. falciparum infection demonstrated marked lability in radiotracer uptake across all regions of the brain, exceeding expected normal variation (within subject coefficient of variation (wCV): 14.4%) compared to the relatively stable uptake in participants with P. vivax infection (wCV: 3.5%). No consistent imaging changes suggestive of microvascular dysfunction were observed in either group. Neuroimaging in early IBSM studies is safe and technically feasible, with preliminary results suggesting that differences in brain tropism between P. falciparum and P. vivax may occur very early in infection. [ABSTRACT FROM AUTHOR]

The use of quantitative qRT-PCR assays for detection and quantification of late gametocyte stages has revealed the high transmission capacity of the human malaria parasite, Plasmodium falciparum. To understand how the parasite adjusts its transmission in response to in-host environmental conditions including antimalarials requires simultaneous quantification of early and late gametocytes. Here, we describe qRT-PCR assays that specifically detect and quantify early-stage P. falciparum gametocytes. The assays are based on expression of known early and late gametocyte genes and were developed using purified stage II and stage V gametocytes and tested in natural and controlled human infections. Genes pfpeg4 and pfg27 are specifically expressed at significant levels in early gametocytes with a limit of quantification of 190 and 390 gametocytes/mL, respectively. In infected volunteers, transcripts of pfpeg4 and pfg27 were detected shortly after the onset of blood stage infection. In natural infections, both early (pfpeg4/pfg27) and late gametocyte transcripts (pfs25) were detected in 71.2% of individuals, only early gametocyte transcripts in 12.6%, and only late gametocyte transcripts in 15.2%. The pfpeg4/pfg27 qRT-PCR assays are sensitive and specific for quantification of circulating sexually committed ring stages/early gametocytes and can be used to increase our understanding of epidemiological processes that modulate P. falciparum transmission. [ABSTRACT FROM AUTHOR]

Intracellular tau inclusions are a pathological hallmark of Alzheimer's disease, progressive supranuclear palsy, corticobasal degeneration and other sporadic neurodegenerative tauopathies. Recent in vitro and in vivo studies have shown that tau aggregates may spread to neighbouring cells and functionally connected brain regions, where they can seed further tau aggregation. This process is referred to as tau propagation. Here we describe an ex vivo system using organotypic hippocampal slice cultures (OHCs) which recapitulates aspects of this phenomenon. OHCs are explants of hippocampal tissue which may be maintained in culture for months. They maintain their synaptic connections and multicellular 3D architecture whilst also permitting direct control of the environment and direct access for various analysis types. We inoculated OHCs prepared from P301S mouse pups with brain homogenate from terminally ill P301S mice and then examined the slices for viability and the production and localization of insoluble phosphorylated tau. We show that following seeding, phosphorylated insoluble tau accumulate in a time and concentration dependent manner within OHCs. Furthermore, we show the ability of the conformation dependent anti-tau antibody, MC1, to compromise tau accrual in OHCs, thus showcasing the potential of this therapeutic approach and the utility of OHCs as an ex vivo model system for assessing such therapeutics. [ABSTRACT FROM AUTHOR]

Genomoviruses (family Genomoviridae) are circular single-stranded DNA viruses that have been mainly identified through metagenomics studies in a wide variety of samples from various environments. Here, we describe 98 genomes of genomoviruses found associated with members of 19 plant families from Australia, Brazil, France, South Africa and the USA. These 98 genomoviruses represent 29 species, 26 of which are new, in the genera Gemykolovirus (n = 37), Gemyduguivirus (n = 9), Gemygorvirus (n = 8), Gemykroznavirus (n = 6), Gemycircularvirus (n = 21) and Gemykibivirus (n = 17). [ABSTRACT FROM AUTHOR]

Climate change is expected to result in more frequent periods of both low rainfall and above normal temperatures for many coffee growing regions. To understand how coffee reacts to such change, we studied the physiological and gene expression responses of the clonal variety C. canephora FRT07 exposed to water deficits under two different temperature regimes. Variations in the time-dependent impact of water deficits on leaf stomatal conductance and carbon assimilation were significantly different under the 27 °C and 27 °C/42 °C conditions examined. The physiological responses 24 h after re-watering were also different for both conditions. Expression analysis of genes known to respond to water deficits indicated that drought-related signaling occurred at both temperatures. Deeper insights into the response of coffee to water deficits was obtained by RNASeq based whole transcriptome profiling of leaves from early, late, and recovery stages of the 27 °C experiment. This yielded expression data for 13,642 genes and related differential expression analysis uncovered 362 and 474 genes with increased and decreased expression, respectively, under mild water deficits, and 1627 genes and 2197 genes, respectively, under more severe water deficits. The data presented, from a single clonal coffee variety, serves as an important reference point for future comparative physiological/transcriptomic studies with clonal coffee varieties with different sensitivities to water deficits and high temperatures. Such comparative analyses will help predict how different coffee varieties respond to changing climatic conditions, and may facilitate the identification of alleles associated with high and low tolerance to water deficits, enabling faster breeding of more climate-smart coffee trees. [ABSTRACT FROM AUTHOR]

Context: Most future predictions of forest diversity and composition assume species will shift instantaneously. However, evidence suggests there will be considerable inertia between climate change and shifts in plant species distributions, for example due to resident communities resisting changes, the redistribution of resident species' abundances, and dispersal limitation of species attempting to track preferred climates. Objectives: To test how inertia in community responses to climate change may affect future primary productivity, and the capacity for communities to respond through local redistribution of abundances. Methods: We assessed relationships between community functional trait distributions, climate and environment with a remote-sensed measure of gross primary productivity (GPP) across 1032 woody plant communities and projected these spatially under current and future climates. Using a simulation approach, we also tested the capacity for communities to achieve future trait distributions by shifting the relative abundances of resident species. Results: We found that climate change is likely to reduce GPP in southeast Queensland, and, contrary to expectations, there is little evidence to suggest distributional inertia will contribute substantially to this loss. We show that sites with high existing functional diversity are well-placed to achieve predicted future trait compositions in the absence of long-distance dispersal through redistribution of resident species abundances. Conclusions: Our results show that sites with high existing functional diversity are well placed to achieve predicted future trait compositions in the absence of long-distance dispersal through abundance redistribution of resident species, but it is unlikely this will mitigate strong climate change-driven losses of productivity. [ABSTRACT FROM AUTHOR]

Physically disrupting microorganism membranes to enable antibiotics to overcome resistance mechanisms that inhibit or excrete antibiotics has great potential for reducing antibiotic doses and rendering resistance mechanisms inert. We demonstrate the synergistic inactivation of a Gram-positive (Staphylococcus aureus) and two Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria by combining 222 30 kV/cm electric pulses (EPs) or 500 20 kV/cm EPs with 300-ns EP duration with various antibiotics with different mechanisms of action is demonstrated. Doses of antibiotics that produced no inactivation in 10 min of exposure in solution with bacteria induced several log reductions under the influence of nanosecond EPs. Combining 2 μg/L or 20 μg/mL of rifampicin with the 30 kV/cm EPs enhanced Staphylococcus aureus inactivation compared with EPs alone, while only a few of the other combinations demonstrated improvement. Combining 2 μg/L or 20 μg/mL of mupirocin or rifampicin with either EP train enhanced E. coli inactivation compared with EPs alone. Combining 2 μg/L or 20 μg/mL of erythromycin or vancomycin with the 30 kV/cm EPs enhanced E. coli inactivation compared with EPs alone. These results indicate that EPs can make Gram-positive antibiotics efficient for inactivating Gram-negative bacteria with future studies required to optimize EP parameters for other antibiotics and Gram-negative bacteria. [ABSTRACT FROM AUTHOR]

Context: In response to predominantly local and private approaches to landscape change, landscape ecologists should critically assess the multiscalar influences on landscape design.Objectives: This study develops a governance framework for Nassauer and Opdam’s “Design-in-Science” model. Its objective is to create an approach for examining hierarchical constraints on landscape design in order to investigate linkages among urban greening initiatives, patterns of landscape change, and the broader societal values driving those changes. It aims to provide an integrative and actionable approach for landscape sustainability science.Methods: This framework is examined through an ethnographic study of public policy processes surrounding the urban tree initiatives in Boston, MA; Philadelphia, PA; and Baltimore, MD.Results: These initiatives demonstrate the impact of political and economic decentralization on urban landscape patterns. Their collaborative governance approach incorporates diverse resources to implement programming at a fine-scale. The predominant tree giveaway program fragments the urban and regional forest.Conclusion: Spatial and temporal fragmentation undermines the long-term security of urban greening programs, and it suggests reconsideration of the role of state regimes in driving broad scale spatial planning. [ABSTRACT FROM AUTHOR]

Elucidation of the evolutionary history and interrelatedness of Plasmodium species that infect humans has been hampered by a lack of genetic information for three human-infective species: P. malariae and two P. ovale species (P. o. curtisi and P. o. wallikeri). These species are prevalent across most regions in which malaria is endemic and are often undetectable by light microscopy, rendering their study in human populations difficult. The exact evolutionary relationship of these species to the other human-infective species has been contested. Using a new reference genome for P. malariae and a manually curated draft P. o. curtisi genome, we are now able to accurately place these species within the Plasmodium phylogeny. Sequencing of a P. malariae relative that infects chimpanzees reveals similar signatures of selection in the P. malariae lineage to another Plasmodium lineage shown to be capable of colonization of both human and chimpanzee hosts. Molecular dating suggests that these host adaptations occurred over similar evolutionary timescales. In addition to the core genome that is conserved between species, differences in gene content can be linked to their specific biology. The genome suggests that P. malariae expresses a family of heterodimeric proteins on its surface that have structural similarities to a protein crucial for invasion of red blood cells. The data presented here provide insight into the evolution of the Plasmodium genus as a whole. [ABSTRACT FROM AUTHOR]

Computed tomography revealed transverse colonic intussusception with a hepatic flexure lipoma acting as the lead point (Fig. Intestinal intussusception: etiology, diagnosis, and treatment. [Extracted from the article]

The obliteration of intra-thoracic dead space following tumor or empyema extirpation is imperative to successful long-term outcomes. We sought to describe the technique of using a pedicled latissmus dorsi muscle flap for obliteration of a large 14 × 6cm intrathoracic dead space following pleural decortication of chronic empyema, without thoracotomy or rib spreading via video-assisted thoracoscopic surgery (VATS). Specific attention is directed to the technical details of the flap harvest and inset in relation to the modifications required to inset the flap without a thoracotomy or rib spreading. The patient's history, presenting symptoms, pre-operative imaging, intraoperative details, and post-operative course are delineated with a focus on the length of stay, post-operative pain, and morbidity. The length of stay was 2 days with minimal pain on post-operative day one managed with oral nacrotic; long term post-operative X-ray revealed obliterated dead space and the patient experienced no complications. Inset of pedicled latissmus muscle flaps via VATS technique without thoracotomy or rib spreading seems a safe and effective technique that can offer short hospitalization with minimal pain morbidity. Level of Evidence: Level V, therapeutic study [ABSTRACT FROM AUTHOR]

We have reached a crucial turning point in debates around climate change. A well established scientific consensus regarding the physical causes, dynamics, and at least many likely implications of anthropogenic climate change has thus far failed to result in any substantial movement towards mitigation. For many, then, the most urgent questions regarding climate change are now socio-cultural ones, such as: how do people come to hold and act on certain beliefs regarding environmental conditions and processes; how do institutional forms and histories shape and constrain the views and options of various sorts of actors; and what are relationships among fossil fuels, climate change, and the historical geographies and future trajectories of capitalism? Far from being simpler than physical and life science questions, these social science questions introduce entirely new sorts of actors, dynamics, and methodological challenges into this already complex and dynamic domain. This special issue takes up these topics. In this essay, we chart some of the major contours of contemporary social science thinking regarding climate change and introduce the articles in the special issue. We begin by examining work, from political science and scholarship on the commons, that foregrounds questions of sovereignty, territoriality, and cooperation with respect to environmental governance. Then we examine work from neoclassical economics and radical political economy, which frame climate change in terms of externalities, or contradiction and crisis, respectively. Finally, we examine the rapidly proliferating work exploring how individuals think and feel about these issues, emphasizing concepts of risk, communication, and governmentality. [ABSTRACT FROM AUTHOR]

The original article can be found online at https://doi.org/10.1038/s41467-020-19988-z. The original version of this Article contained an error in Supplementary Table 3 giving details on used primers and probes. [Extracted from the article]

Inflammatory pathway plays an important role in tumor cell progression of colorectal cancers. Although colon cancer is considered as one of the leading causes of death worldwide, very few drugs are available for its effective treatment. Many studies have examined the effects of specific COX-2 and 5-LOX inhibitors on human colorectal cancer, but the role of isothiocyanates (ITSCs) as COX-LOX dual inhibitors engaged in hyaluronan-CD44 interaction has not been studied. In the present work, we report series of ITSC analogs incorporating bioisosteric thiosemicarbazone moiety. These inhibitors are effective against panel of human colon cancer cell lines including COX-2 positive HCA-7, HT-29 cells lines, and hyaluronan synthase-2 (Has2) enzyme over-expressing transformed intestinal epithelial Apc10.1Has2 cells. Specifically, our findings indicate that HA-CD44v6-mediated COX-2/5-LOX signaling mediate survivin production, which in turn, supports anti-apoptosis and chemo-resistance leading to colon cancer cell survival. The over-expression of CD44v6shRNA as well as ITSC treatment significantly decreases the survival of colon cancer cells. The present results thus offer an opportunity to evolve potent inhibitors of HA synthesis and CD44v6 pathway and thus underscoring the importance of the ITSC analogs as chemopreventive agents for targeting HA/CD44v6 pathway. [ABSTRACT FROM AUTHOR]

Recent work on legal geographies has arguably paid far too little attention to the environment as both an object of governance and a terrain of struggle with respect to the law. Conversely, political ecology as a field, with its focus on informal and extra-legal dynamics, has arguably engaged too little with the legal geographies that are central to environmental conflicts in many locations. This paper examines and theorizes the legal geographies that have been essential elements of the recent boom in extraction of natural gas from the Marcellus Shale in Pennsylvania. Specifically, it examines the ways in which laws and the authority of the state more broadly have been changed, deployed, and invoked, particularly through the passage of Act 13, to enable the extraction of the gas in the shale and its circulation as a viable commodity. This analysis of the relevant multiscalar legal geographies illustrates the productivity of a more direct engagement between political ecology on one hand, and legal geography on the other. [ABSTRACT FROM AUTHOR]

Phenylalanine ammonia lyase (PAL) is the first entry enzyme of the phenylpropanoid pathway producing phenolics, widespread constituents of plant foods and beverages, including chlorogenic acids, polyphenols found at remarkably high levels in the coffee bean and long recognized as powerful antioxidants. To date, whereas PAL is generally encoded by a small gene family, only one gene has been characterized in Coffea canephora ( CcPAL1), an economically important species of cultivated coffee. In this study, a molecular- and bioinformatic-based search for CcPAL1 paralogues resulted successfully in identifying two additional genes, CcPAL2 and CcPAL3, presenting similar genomic structures and encoding proteins with close sequences. Genetic mapping helped position each gene in three different coffee linkage groups, CcPAL2 in particular, located in a coffee genome linkage group (F) which is syntenic to a region of Tomato Chromosome 9 containing a PAL gene. These results, combined with a phylogenetic study, strongly suggest that CcPAL2 may be the ancestral gene of C. canephora. A quantitative gene expression analysis was also conducted in coffee tissues, showing that all genes are transcriptionally active, but they present distinct expression levels and patterns. We discovered that CcPAL2 transcripts appeared predominantly in flower, fruit pericarp and vegetative/lignifying tissues like roots and branches, whereas CcPAL1 and CcPAL3 were highly expressed in immature fruit. This is the first comprehensive study dedicated to PAL gene family characterization in coffee, allowing us to advance functional studies which are indispensable to learning to decipher what role this family plays in channeling the metabolism of coffee phenylpropanoids. [ABSTRACT FROM AUTHOR]

Chloroplast transformation offers an exciting platform for the safe, inexpensive and large-scale production of recombinant proteins in plants. An important advantage for the isolation of proteins produced in the chloroplast would be the use of affinity tags for rapid purification by affinity chromatography. To date, only His-tags have been used. In this study, we have tested the feasibility of expressing two additional affinity tags: glutathione- S-transferase (GST) and a His-tagged derivative of the maltose-binding protein (His-MBP). By using the chloroplast 16S rRNA promoter and 5′ untranslated region of phage T7 gene 10, GST and His-MBP were expressed in homoplastomic tobacco plants at approximately 7% and 37% of total soluble protein, respectively. GST could be purified by one-step-affinity purification using a glutathione column. Much better recoveries were obtained for His-MBP by using a twin-affinity purification procedure involving first immobilised nickel followed by binding to amylose. Interestingly, expression of GST led to cytoplasmic male sterility. Overall, our work expands the tools available for purifying recombinant proteins from the chloroplast. [ABSTRACT FROM AUTHOR]

US public awareness of the reality and risks of human-caused climate change remains limited, despite strong evidence presented in the IPCC and other major climate assessments. One contributing factor may be that the immense collective effort to produce periodic climate assessments is typically not well matched with public communication and outreach efforts for these reports, leaving a vacuum to be filled by less authoritative sources. Print and online media coverage provides one metric of the US public reach of selected climate assessments between 2000 and 2010. The number of Lexis-Nexis articles for the search terms ' climate change' or ' global warming' within 14 days of each report's release varied significantly over time with a peak occurring in 2007. When compared to background ' chatter' relating to climate change, each assessment had widely diverse penetration in the US media (~4% for US National Climate Assessment in 2000; ~17% for Arctic Climate Impacts Assessment in 2004; ~19% and ~10% for Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report Working Group I and Working Group II respectively in 2007; ~4% for the US Global Change Research Program (USGCRP) assessment report in 2009; and ~5% for US National Research Council's America's Climate Choices reports in 2010). We propose ways to improve the public reach of climate assessments, focusing in particular on approaches to more effectively characterize and communicate the role of uncertainty in human actions as distinct from other sources of uncertainty across the range of possible climate futures. [ABSTRACT FROM AUTHOR]

By applying a directed evolution methodology specific enzymatic characteristics can be enhanced, but to select mutants of interest from a large mutant bank, this approach requires high throughput screening and facile selection. To facilitate such primary screening of enhanced clones, an expression system was tested that uses a green fluorescent protein (GFP) tag from Aequorea victoria linked to the enzyme of interest. As GFP’s fluorescence is readily measured, and as there is a 1:1 molar correlation between the target protein and GFP, the concept proposed was to determine whether GFP could facilitate primary screening of error-prone PCR (EPP) clones. For this purpose a thermostable β-glucosidase (BglA) from Fervidobacterium sp. was used as a model enzyme. A vector expressing the chimeric protein BglA-GFP-6XHis was constructed and the fusion protein purified and characterized. When compared to the native proteins, the components of the fusion displayed modified characteristics, such as enhanced GFP thermostability and a higher BglA optimum temperature. Clones carrying mutant BglA proteins obtained by EPP, were screened based on the BglA/GFP activity ratio. Purified tagged enzymes from selected clones resulted in modified substrate specificity. [ABSTRACT FROM AUTHOR]

The papers in this Special Issue are the primary technical underpinnings for the Northeast Climate Impacts Assessment (NECIA), an integrated regional-scale assessment of projected climate change, impacts and options for mitigation and adaptation across the US Northeast. The consequences of future pathways of greenhouse gas emissions on projected climate and impacts across climate-sensitive sectors is assessed by using downscaled projections from three global climate models under both higher (Alfi) and lower (B1) emissions scenarios. The findings illustrate that near-term reductions in emissions can greatly reduce the extent and severity of regionally important impacts on natural and managed ecosystems and public health in the latter half of this century, and increase the feasibility that those impacts which are now unavoidable can be successfully managed through adaptation. [ABSTRACT FROM AUTHOR]

An EST database has been generated for coffee based on sequences from approximately 47,000 cDNA clones derived from five different stages/tissues, with a special focus on developing seeds. When computationally assembled, these sequences correspond to 13,175 unigenes, which were analyzed with respect to functional annotation, expression profile and evolution. Compared with Arabidopsis, the coffee unigenes encode a higher proportion of proteins related to protein modification/turnover and metabolism—an observation that may explain the high diversity of metabolites found in coffee and related species. Several gene families were found to be either expanded or unique to coffee when compared with Arabidopsis. A high proportion of these families encode proteins assigned to functions related to disease resistance. Such families may have expanded and evolved rapidly under the intense pathogen pressure experienced by a tropical, perennial species like coffee. Finally, the coffee gene repertoire was compared with that of Arabidopsis and Solanaceous species (e.g. tomato). Unlike Arabidopsis, tomato has a nearly perfect gene-for-gene match with coffee. These results are consistent with the facts that coffee and tomato have a similar genome size, chromosome karyotype (tomato, n=12; coffee n=11) and chromosome architecture. Moreover, both belong to the Asterid I clade of dicot plant families. Thus, the biology of coffee (family Rubiacaeae) and tomato (family Solanaceae) may be united into one common network of shared discoveries, resources and information. [ABSTRACT FROM AUTHOR]

Abnormal bone metabolism is a recognized complication of end-stage renal disease, but fracture risk following renal transplantation has not been well quantified. We followed the 86 Olmsted County, Minnesota, residents who underwent initial renal transplantation in 1965–1995 for 911 person-years (median, 10.6 years per subject) in a retrospective cohort study. Fractures, and possible risk factors, were assessed through review of each subject’s complete community medical records. Altogether, 117 fractures were observed during follow-up extending to 33 years. The cumulative incidence of any fracture at 15 years was 60% versus 20% expected (P<0.001). There was a significantly increased risk of fractures generally [standardized incidence ratio (SIR), 4.8; 95% CI, 3.6–6.4] and vertebral (SIR, 23.1; 95% CI, 12.3–39.6) and foot fractures (SIR, 8.4; 95% CI, 5.1–12.9) especially. Age at first transplantation, renal failure due to diabetes, pancreas transplantation, peripheral neuropathy, peripheral vascular disease and blindness were all associated with overall fracture risk. In a multivariate analysis, however, only age and diabetic nephropathy were independent predictors of fracture risk generally, while higher activity status was protective. Diabetes was the only independent predictor of lower limb fractures, whereas age and osteoporosis history predicted vertebral fractures. Cumulative corticosteroid dosage was not associated with increased fracture risk in this analysis. Despite the fact that our patients had few risk factors for preexisting bone disease attendant to postmenopausal osteoporosis, prior corticosteroid use or renal osteodystrophy, these data indicate that renal transplantation is associated with a significant increase in fracture risk among unselected patients in the community. Diabetic patients, particularly, experience excess lower limb fractures. Patients and their care providers should be aware of this elevated fracture risk, which continues long-term. [ABSTRACT FROM AUTHOR]

Physicians who treat patients with infective endocarditis (IE) are encountering a growing number of dialysis and kidney transplant patients. Both groups have 30 to 100 times higher risk of IE, with 1-year mortalities of 40% to 60%. The predominant organisms causing IE are gram positive, with 60% to 80% of cases due to Staphylococcus aureus, and another 10% to 20% of cases due to coagulase-negative staphylococci. Renal transplant patients may develop fungal IE, but this risk is primarily in the first 3 months after transplant. In addition to blood cultures, transesophageal echocardiogram is the most useful diagnostic examination for IE in these patients. Initial antibiotic therapy, pending final culture and antibiotic susceptibility results, should provide coverage against the most common organisms and allow for the potential of either methicillin or vancomycinresistant species. Removal of infected hemodialysis access devices and at least 4 to 6 weeks of intravenous antibiotics are recommended. Antibiotic prophylaxis against IE has been recommended for all dialysis and renal transplant patients, but this strategy is controversial and unproven. [ABSTRACT FROM AUTHOR]

Aspartic proteinase (EC 3.4.23) activity plays a pivotal role in the degradation of Theobroma cacao L. seed proteins during the fermentation step of cacao bean processing. Therefore, this enzyme is believed to be critical for the formation of the peptide and amino acid cocoa flavor precursors that occurs during fermentation. Using cDNA cloning and northern blot analysis, we show here that there are at least two distinct aspartic proteinase genes (TcAP1 and TcAP2) expressed during cacao seed development. Both genes are expressed early during seed development and their mRNA levels decrease towards the end of seed maturation. TcAP2 is expressed at a much higher level than TcAP1, although the expression of TcAP1 increases slightly during germination. The proteins encoded by TcAP1 and TcAP2 are relatively different from each other (73% identity). This, and the fact that the two corresponding genes have different expression patterns, suggests that the TcAP1 and TcAP2 proteins may have different functions in the maturing seeds and during germination. Because the TcAP2 gene is expressed at a much higher level during seed development than TcAP1, it is likely that the TcAP2 protein is primarily responsible for the majority of the industrially important protein hydrolysis that occurs during cacao bean fermentation. Finally, TcAP2 has been functionally expressed in the yeast Yarrowia lipolytica. The secreted recombinant protein is able to hydrolyse bovine haemoglobin at acidic pH and is sensitive to pepstatin A, confirming that TcAP2 encodes an aspartic proteinase, and strongly suggests that this gene encodes the well-characterized aspartic proteinase of mature cacao seeds. [ABSTRACT FROM AUTHOR]

We examined the temporal and spatial variability of urea concentrations and urea uptake and regeneration rates collected on cruises along the longitudinal axis of the Chesapeake Bay between 1972 and 1998. Interannually, mean Bay-wide surface urea concentrations ranged between 0.49 and 0.91 µg-at N 1[sup -1] with a nearly 50% decrease in surface concentrations observed between 1988 and 1998. Concentrations of urea from samples collected within ∼1 m of the bottom were generally higher and much more variable than surface samples. Seasonally, two different patterns were observed in mean Bay-wide surface urea concentrations. Urea concentrations from near surface waters exhibited a clear summer peak for 1988 through 1994, while for 1973 and 1996 to 1998 a distinct winter-spring peak in concentration was observed. Urea concentrations from deeper waters showed a similar seasonal trend each year with peak concentrations measured in spring. Spatially, urea concentrations in the surface waters decreased in a conservative-type pattern from 0.91 µg-at N 1[sup -1] at the freshwater end member to 0.46 µg-at N 1[sup -1] at the ocean end member. Mean Bay-wide surface urea uptake rates displayed a seasonal pattern throughout the data set with maximum uptake rates (up to 0.33 µg-at N 1[sup -1] h[sup -1]) consistently observed during summer. Mean Bay-wide surface regeneration rates were highest but most variable during fall (1.63 ± 0.82 µg-at N 1[sup -1] h[sup -1]). Mean urea uptake and regeneration rates displayed opposing spatial trends along the axis of the Bay with uptake rates being lowest in the North Bay where regeneration rates were highest. The average temporal and spatial patterns of urea concentration in Chesapeake Bay appear to reflect a balance between external inputs and internal biological recycling. [ABSTRACT FROM AUTHOR]

Melanoma chondroitin sulphate proteoglycan (MCSP) is a cell-surface antigen that has been implicated in the growth and invasion of melanoma tumours. Although this antigen is expressed early in melanoma progression, its biological function is unknown. MCSP can stimulate the integrin-α[sub 4]β[sub 1]-mediated adhesion and spreading of melanoma cells. Here we show that stimulated MCSP recruits tyrosine-phosphorylated p30[sup cas], an adaptor protein important in tumour cell motility and invasion. MCSP stimulation also results in a pronounced activation and recruitment of the Rho-family GTPase Cdc42. MCSP-induced spreading of melanoma cells is dependent upon active Cdc42, a Cdc42-associated tyrosine kinase (Ack-1) and tyrosine phosphorylation of p130[sup cas]. Furthermore, vectors inhibiting Ack-1 or Cdc42 expression and/or function abrogate MCSP-induced tyrosine phosphorylation and recruitment of p130[sup cas]. Our findings indicate that MCSP may modify tumour growth or invasion by a unique signal-transduction pathway that links Cdc42 activation to downstream tyrosine phosphorylation and subsequent cytoskeletal reorganization. [ABSTRACT FROM AUTHOR]

Melanoma chondroitin sulphate proteoglycan (MCSP) is a cell-surface antigen that has been implicated in the growth and invasion of melanoma tumours. Although this antigen is expressed early in melanoma progression, its biological function is unknown. MCSP can stimulate the integrin-α[sub 4]β[sub 1]-mediated adhesion and spreading of melanoma cells. Here we show that stimulated MCSP recruits tyrosine-phosphorylated p30[sup cas], an adaptor protein important in tumour cell motility and invasion. MCSP stimulation also results in a pronounced activation and recruitment of the Rho-family GTPase Cdc42. MCSP-induced spreading of melanoma cells is dependent upon active Cdc42, a Cdc42-associated tyrosine kinase (Ack-1) and tyrosine phosphorylation of p130[sup cas]. Furthermore, vectors inhibiting Ack-1 or Cdc42 expression and/or function abrogate MCSP-induced tyrosine phosphorylation and recruitment of p130[sup cas]. Our findings indicate that MCSP may modify tumour growth or invasion by a unique signal-transduction pathway that links Cdc42 activation to downstream tyrosine phosphorylation and subsequent cytoskeletal reorganization. [ABSTRACT FROM AUTHOR]

This paper proposes and carries out a two-stage analysis of the determinants of desired family size, using data gathered from a sample of women in the city of Ilorin, Nigeria. The analysis first focuses on differences between women who report numerical family size desires and those who report nonnumerical desires. Findings suggest that there are important differences between these two groups, but there is little variation in the actual number reported by those expressing numerical desires. Implications of these findings for survey design are discussed. In particular, the practice of forcing numerical responses by instructing interviewers to probe when women report nonnumerical desires is questioned. [ABSTRACT FROM AUTHOR]

Data from the June 1980 Current Population Survey on fathers' reported provision of financial support to children from previous marriages living elsewhere is compared to previously published tabulations from the April 1979 CPS of women's receipt of child support payments. The comparison indicates that the number of men with children from previous marriages living elsewhere is substantially underreported in the June 1980 CPS. Because of the apparent underreporting, the data on the provision of financial support should be interpreted with caution. [ABSTRACT FROM AUTHOR]

This paper applies the techniques of multiple decrement life tables to marriage histories collected as part of the 1973 National Survey of Family Growth, in an attempt to examine differences in pattern and level of marriage dissolution by marriage order. The paper considers the process of marriage dissolution in two stages--marriage to separation and separation to divorce--in addition to considering the composite of these two, marriage to divorce. Second marriages are more likely to reamin intact only for blacks. For all subgroups of whites, second marriages are either as likely or more likely to dissolve than first marriages. For both first and second marriages, blacks are considerably less likely to obtain a divorce after separation. [ABSTRACT FROM AUTHOR]

Renal and urologic complications are not uncommon in patients with inflammatory bowel disease, and can be directly or indirectly related to the underlying disease process or its treatment. Many of these patients have asymptomatic disease, or the urinary symptoms are nonspecific or overshadowed by bowel symptoms. By the time a urinary complication is considered, significant disease progression or renal damage may have occurred. These risks necessitate a high degree of diligence and periodic urologic evaluation as part of the long-term management of patients with inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

Amiodarone has potent and complex antiarrhythmic effects associated with a rare incidence of proarrhythmia. For a comprehensive understanding of its antiarrhythmic mechanisms in the same preparations, amiodarone (50 µM) was employed as it would be in the clinical setting and applied to guinea pig papillary muscles impaled by microelectrodes, paced at different rates, and superfused with various concentrations of potassium ([K]). Amiodarone exerted complex actions, as follows: (1) The maximum rate of rise (V) of the fast action potential (i.e., [K] = 5.4−9.0mM) as well as that of the slow action potential (i.e., [K] = 15.0mM in the presence of 1.0µM isoproterenol) was suppressed in a rate-dependent manner. (2) Amiodarone exhibited a rate- and [K]-dependent increase in the ratio of effective refractory period vs action potential duration at 90% repolarization (ERP/APD), disclosing post-repolarization refractoriness. (3) Amiodarone had no effect on passive cable factors, such as threshold current and tissue resistance, during propagation. These versatile electrophysiological effects of amiodarone may contribute to its unique antiarrhythmic effects, as well as the low incidence of proarrhythmia with this drug. [ABSTRACT FROM AUTHOR]

Malaria is spread by the transmission of sexual stage parasites, called gametocytes. However, with Plasmodium falciparum, gametocytes can only be detected in peripheral blood when they are mature and transmissible to a mosquito, which complicates control efforts. Here, we identify the set of genes overexpressed in patient blood samples with high levels of gametocyte-committed ring stage parasites. Expression of all 18 genes is regulated by transcription factor AP2-G, which is required for gametocytogenesis. We select three genes, not expressed in mature gametocytes, to develop as biomarkers. All three biomarkers we validate in vitro using 6 different parasite lines and develop an algorithm that predicts gametocyte production in ex vivo samples and volunteer infection studies. The biomarkers are also sensitive enough to monitor gametocyte production in asymptomatic P. falciparum carriers allowing early detection and treatment of infectious reservoirs, as well as the in vivo analysis of factors that modulate sexual conversion. Malaria gametocytes are sexual-stage parasites transmitted from mammalian host's blood back to their insect vector. Here, Prajapati et al. identify gametocyte-committed ring-stage biomarkers allowing to forecast malaria transmission potential. [ABSTRACT FROM AUTHOR]