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The Expert Consensus Guideline Series. Treatment of behavioral emergencies.

OBJECTIVES: Behavioral emergencies are a common and serious problem for consumers, their communities, and the healthcare settings on which they rely to contain, assess, and ultimately help the individual in a behavioral crisis. Partly because of the inherent dangers of this situation, there is little research to guide provider responses to this challenge. Key constructs such as agitation have not been adequately operationalized so that the criteria defining a behavioral emergency are vague. The significant progress that has been made for some disease states with better treatments and higher consumer acceptance has not penetrated this area of practice. A significant number of deaths of patients in restraint has focused government and regulators on these issues, but a consensus about key elements in the management of behavioral emergencies has not yet been articulated by the provider community. The authors assembled a panel of 50 experts to define the following elements: the threshold for emergency interventions, the scope of assessment for varying levels of urgency and cooperation, guiding principles in selecting interventions, and appropriate physical and medication strategies at different levels of diagnostic confidence and for a variety of etiologies and complicating conditions. METHOD: In order to identify issues in this area on which there is consensus, a written survey with 808 decision points was developed. The survey was mailed to a panel of 52 experts, 50 of whom completed it. A modified version of the RAND Corporation 9-point scale for rating appropriateness of medical decisions was used to score options. Consensus on each option was defined as a non-random distribution of scores by chi-square "goodness-of-fit" test. We assigned a categorical rank (first line/preferred choice, second line/alternate choice, third line/usually inappropriate) to each option based on the 95% confidence interval around the mean rating. Guideline tables were constructed describing the preferred strategies in key clinical situations. RESULTS: The expert panel reached consensus on 83% of the options. The relative appropriateness of emergency interventions was ascertained for a continuum of behaviors. When asked about the frequency with which emergency interventions (parenteral medication, restraints, seclusion) were required in their services, 47% of the experts reported that such interventions were necessary for 1%-5% of patients seen in their services and 32% for 6%-20%. In general, the consensus of this panel lends support to many elements of recent Health Care Financing Administration regulations, including the timing of clinician assessment and reassessment and the intensity of nursing care. However, the panel did not endorse the concept of "chemical restraint," instead favoring the idea that medications are treatments for target behaviors in behavioral emergencies even when the causes of these behaviors are not well understood. Control of aggressive behavior emerged as the highest priority during the emergency; however, preserving the physician-patient relationship was rated a close second and became the top priority in the long term. Oral medications, particularly concentrates, were clearly preferred if it is possible to use them. Benzodiazepines alone were top rated in 6 of 12 situations. High-potency conventional antipsychotics used alone never received higher ratings than benzodiazepines used alone. A combination of a benzodiazepine and an antipsychotic was preferred for patients with suspected schizophrenia, mania, or psychotic depression. There was equal support for high-potency conventional or atypical antipsychotics (particularly liquids) in oral combinations with benzodiazepines. Droperidol emerged in fourth place in some situations requiring an injection. CONCLUSIONS: To evaluate many of the treatment options in this survey, the experts had to extrapolate beyond controlled data in comparing modalities with each other or in combination. Within the limits of expert opinion and with the expectation that future research data will take precedence, these guidelines provide some direction for addressing common clinical dilemmas in the management of psychiatric emergencies and can be used to inform clinicians in acute care settings regarding the relative merits of various strategies.

Aggression↗

Nutrient-limited food webs with up to three trophic levels: feasibility, stability, assembly rules, and effects of nutrient enrichment.

Community structure is controlled, among multiple factors, by competition and predation. Using the R* rule and graphical analysis, we analyse here the feasibility, stability and assembly rules of resource-based food webs with up to three trophic levels. In particular, we show that (1) the stability of a food web with two plants and two generalist herbivores does not require that plants' resource exploitation abilities trade-off with resistance to the two herbivores, and (2) food webs with two plants and either one generalist herbivore and a carnivore or two generalist herbivores and two generalist carnivores are not feasible because of cascade competition between top consumers. The relative strength of species interactions and the relative impacts of plants and herbivores on factors which control their growth also play a critical role. We discuss how community structure constrains assembly rules and yields cascades of extinctions in food webs.

Animals↗

Phylogenetic diversity of marine cyanophage isolates and natural virus communities as revealed by sequences of viral capsid assembly protein gene g20.

In order to characterize the genetic diversity and phylogenetic affiliations of marine cyanophage isolates and natural cyanophage assemblages, oligonucleotide primers CPS1 and CPS8 were designed to specifically amplify ca. 592-bp fragments of the gene for viral capsid assembly protein g20. Phylogenetic analysis of isolated cyanophages revealed that the marine cyanophages were highly diverse yet more closely related to each other than to enteric coliphage T4. Genetically related marine cyanophage isolates were widely distributed without significant geographic segregation (i.e., no correlation between genetic variation and geographic distance). Cloning and sequencing analysis of six natural virus concentrates from estuarine and oligotrophic offshore environments revealed nine phylogenetic groups in a total of 114 different g20 homologs, with up to six clusters and 29 genotypes encountered in a single sample. The composition and structure of natural cyanophage communities in the estuary and open-ocean samples were different from each other, with unique phylogenetic clusters found for each environment. Changes in clonal diversity were also observed from the surface waters to the deep chlorophyll maximum layer in the open ocean. Only three clusters contained known cyanophage isolates, while the identities of the other six clusters remain unknown. Whether or not these unidentified groups are composed of bacteriophages that infect different Synechococcus groups or other closely related cyanobacteria remains to be determined. The high genetic diversity of marine cyanophage assemblages revealed by the g20 sequences suggests that marine viruses can potentially play important roles in regulating microbial genetic diversity.

Bacteriophages↗

Habitat heterogeneity and niche structure of trees in two tropical rain forests.

Dispersal-assembly theories of species coexistence posit that environmental factors play no role in explaining community diversity and structure. Dispersal-assembly theories shed light on some aspects of community structure such as species-area and species-abundance relationships. However, species' environmental associations also affect these measures of community structure. Measurements of species' niche breadth and overlap address this influence. Using a new continuous measure of niche and a dispersal-assembly null model that maintains species' niche breadth and aggregation, we tested two hypotheses assessing the effects of habitat heterogeneity on the ability of dispersal-assembly theories to explain community niche structure. We found that in both homogenous and heterogeneous environments dispersal-assembly theories cannot fully explain observed niche structure. The performance of the dispersal-assembly null models was particularly poor in heterogeneous environments. These results indicate that non-dispersal based mechanisms are in part responsible for observed community structure and measures of community structure which include species' environmental associations should be used to test theories of species diversity.

Altitude↗

[Municipal Health Councils: activity and representation of grassroots communities].

This article was based on the results of research concerning health policy in municipalities that achieved the most extensive development of decentralization and innovation in the State of Rio de Janeiro, Brazil. The study applied a questionnaire for health system users' representatives in Municipal Health Councils. The central issues were: the Councils' political role; social control by the Councils, viewed as surveillance by organized society over government actions; the nature of social representation exercised by the Council members; and the type of mandate they serve. Community representatives in the Councils reinforce aspects pertaining to the exercise of representation in unequal societies. There is a predominance of a differentiated elite consisting of older males with more schooling and higher income than the community average. The notion of "social control" as the basis for the Councils is difficult for the members to grasp. Exercise of representation is diffuse, occurring by way of designation by community associations, election in assemblies, or designation by institutional health policy agencies.

Brazil↗

Six-item screener to identify cognitive impairment among potential subjects for clinical research.

OBJECTIVE: To design a brief cognitive screener with acceptable sensitivity and specificity for identifying subjects with cognitive impairment. DESIGN: Cohort one is assembled from a community-based survey coupled with a second-stage diagnostic evaluation using formal diagnostic criteria for dementia. Cohort two is assembled from referrals to a specialty clinic for dementing disorders that completed the same diagnostic evaluation. SETTING: Urban neighborhoods in Indianapolis, Indiana and the Indiana Alzheimer Disease Center. PATIENTS: Cohort one consists of 344 community-dwelling black persons identified from a random sample of 2212 black persons aged 65 and older residing in Indianapolis; cohort two consists of 651 subject referrals to the Alzheimer Disease Center. MEASUREMENTS: Formal diagnostic clinical assessments for dementia including scores on the Mini-mental state examination (MMSE), a six-item screener derived from the MMSE, the Blessed Dementia Rating Scale (BDRS), and the Word List Recall. Based on clinical evaluations, subjects were categorized as no cognitive impairment, cognitive impairment-not demented, or demented. RESULTS: The mean age of the community-based sample was 74.4 years, 59.4% of the sample were women, and the mean years of education was 10.1. The prevalence of dementia in this sample was 4.3% and the prevalence of cognitive impairment was 24.6%. Using a cut-off of three or more errors, the sensitivity and specificity of the six-item screener for a diagnosis of dementia was 88.7 and 88.0, respectively. In the same sample, the corresponding sensitivity and specificity for the MMSE using a cut-off score of 23 was 95.2 and 86.7. The performance of the two scales was comparable across the two populations studied and using either cognitive impairment or dementia as the gold standard. An increasing number of errors on the six-item screener is highly correlated with poorer scores on longer measures of cognitive impairment. CONCLUSIONS: The six-item screener is a brief and reliable instrument for identifying subjects with cognitive impairment and its diagnostic properties are comparable to the full MMSE. It can be administered by telephone or face-to-face interview and is easily scored by a simple summation of errors.

Black or African American↗

Status of physical exercise and its association with obesity and hypertension in two urban assembly constituencies of East Delhi.

In a community based study using systematic random sampling in two urban Assembly constituencies in East Delhi, 420 subjects above the age of 30 years were interviewed to find out their status regarding physical exercise. People doing regular exercise were found to be only 44.8%. The commonest reason associated for not doing/irregular physical exercise was nonavailability of time (63.3%), followed by no need felt by the respondents to exercise (23.3%). The prevalence of obesity in the group doing regular exercise was much lower than the group that was not doing regular exercise and the results were statistically significant. Though a similar association was found with hypertension also, the results were not statistically significant.

Adult↗

Coarse-grained model of serial dilution dynamics in synthetic human gut microbiome.

Many microbial communities in nature are complex, with hundreds of coexisting strains and the resources they consume. We currently lack the ability to assemble and manipulate such communities in a predictable manner in the lab. Here, we take a first step in this direction by introducing and studying a simplified consumer resource model of such complex communities in serial dilution experiments. The main assumption of our model is that during the growth phase of the cycle, strains share resources and produce metabolic byproducts in proportion to their average abundances and strain-specific consumption/production fluxes. We fit the model to describe serial dilution experiments in hCom2, a defined synthetic human gut microbiome with a steady-state diversity of 63 species growing on a rich media, using consumption and production fluxes inferred from metabolomics experiments. The model predicts serial dilution dynamics reasonably well, with a correlation coefficient between predicted and observed strain abundances as high as 0.8. We applied our model to: (i) calculate steady-state abundances of leave-one-out communities and use these results to infer the interaction network between strains; (ii) explore direct and indirect interactions between strains and resources by increasing concentrations of individual resources and monitoring changes in strain abundances; (iii) construct a resource supplementation protocol to maximally equalize steady-state strain abundances.

Gastrointestinal Microbiome↗

Metabolome-driven rhizosphere microbiome assembly determining the health of medicinal herb (Angelica sinensis) against root rot.

BACKGROUND: The rhizosphere-associated microbiota plays a crucial role in plant responses to disease stress. Plant secondary metabolites are recognized as crucial mediators in the assembly of rhizosphere microbial communities, particularly by enhancing the colonization of beneficial microorganisms. Despite this recognized importance, a deeper understanding of how such metabolome-driven microbiome assembly specifically determines plant resistance against soil-borne diseases is still lacking. RESULTS: Here, we focused on the widely planted medicinal plant Angelica sinensis and demonstrated that root rot-diseased rhizosphere soils (DRS) exhibited a higher relative abundance of Fusarium and a lower relative abundance of Streptomyces compared to healthy rhizosphere soils (HRS). Shotgun metagenomic sequencing revealed that metabolism-associated genes, particularly those related to steroid degradation, are significantly enriched in HRS samples. Subsequent genome and functional gene analysis of Streptomyces revealed that the steroid degradation-related genes are associated with rhizosphere colonization in hosts. Rhizosphere Streptomyces S15 directly antagonized Fusarium and enhanced the root resistance of A. sinensis. Comparative metabolomics showed that A. sinensis plants from HRS secreted more lipid and lipid-like molecules than those from DRS, especially sterol lipids and long-chain fatty acids, which promoted the growth of Streptomyces S15 isolates. Transcriptome analysis validated that the lipid hormones are essential for sporulation, biofilm formation, and streptomycin biosynthesis of S15 strain. Finally, exogenous application of synbiotics (lipid prebiotics and S15) to A. sinensis resulted in the enrichment of S15-homologous Streptomyces amplicon sequence variant (ASV), further establishing beneficial bacterial communities in Fusarium-stressed rhizospheres. CONCLUSIONS: Our study proposes that A. sinensis recruits steroid-metabolizing Streptomyces species by exuding key lipid compounds (i.e., methyl jasmonate and brassinolide) to combat Fusarium root rot. This study provides novel insights into using functional synbiotics as a promising strategy for manipulating plant-microbiome interactions to promote sustainable agriculture. Video Abstract.

Rhizosphere↗

From dissimilarities among species to dissimilarities among communities: a double principal coordinate analysis.

This paper presents a new ordination method to compare several communities containing species that differ according to their taxonomic, morphological or biological features. The objective is first to find dissimilarities among communities from the knowledge about differences among their species, and second to describe these dissimilarities with regard to the feature diversity within communities. In 1986, Rao initiated a general framework for analysing the extent of the diversity. He defined a diversity coefficient called quadratic entropy and a dissimilarity coefficient and proposed a decomposition of this diversity coefficient in a way similar to ANOVA. Furthermore, Gower and Legendre (1986) built a weighted principal coordinate analysis. Using the previous context, we propose a new method called the double principal coordinate analysis (DPCoA) to analyse the relation between two kinds of data. The first contains differences among species (dissimilarity matrix); the second the species distribution among communities (abundance or presence/absence matrix). A multidimensional space assembling the species points and the community points is built. The species points define the original differences between species and the community points define the deduced differences between communities. Furthermore, this multidimensional space is linked with the diversity decomposition into between-community and within-community diversities. One looks for axes that provide a graphical ordination of the communities and project the species onto them. An illustration is proposed comparing bird communities which live in different areas under mediterranean bioclimates. Compared to some existing methods, the double principal coordinate analysis can provide a typology of communities taking account of an abundance matrix and can include dissimilarities among species. Finally, we show that such an approach generalizes some of these methods and allows us to develop new analyses.

Animals↗

Coexistence of multiple food chains in a heterogeneous environment: interactions among community structure, ecosystem functioning, and nutrient dynamics.

A model is developed and analyzed for a nutrient-limited ecosystem containing an arbitrary number of parallel plant-herbivore-detritus food chains in a heterogeneous environment, with a view to exploring interactions among community and ecosystem processes. Physical properties of the environment and functional properties of the entire ecosystem such as nutrient supply, transport, and recycling are shown to exert a profound influence on the composition, diversity, and assembly of the biological community. Community structure as well as the physical properties of the environment in turn affect ecosystem functions such as nutrient and energy flow. In particular, the rate of nutrient transport in the physical medium plays a critical role in competition and coexistence among food chains. The potential for coexistence decreases continuously as the nutrient transport rate increases in food chains with donor-controlled or no herbivory, while it increases continuously or is greatest at an intermediate value of the nutrient transport rate in herbivore-controlled food chains. On the other hand, energy flow generally increases with the rate of nutrient transport. Herbivory also exerts a significant, predictable influence on energy flow and coexistence among plants and food chains.

Animals↗

Heavy-metal stress shapes habitat-specific microbial survival strategies in estuarine environments.

Estuarine ecosystems face increasing heavy metal pollution from rapid urbanization and industrialization, yet the microbial adaptive strategies to multiple metal stressors across different habitats remain poorly understood. This study investigated the diversity and composition of bacterial and fungal communities across free-living (FL), particle-attached (PA), and sediment (SE) fractions from three estuaries with varying heavy metal contamination, and further investigated functional adaptations of bacterial communities. High-throughput amplicon sequencing revealed habitat-specific communities, with SE hosting the highest alpha diversity and enrichment of metal-resistant genera such as Woeseia and Sva1033. Environmental filtering, particularly by Zn, was the dominant driver shaping bacterial assemblages across all habitats, whereas fungal communities displayed greater stochastic assembly patterns. Analysis of 44 high-quality bacterial metagenome-assembled genomes (MAGs) revealed diverse metal resistance genes (cusA, znuB, and zntA), along with enriched metabolic pathways for carbon, nitrogen, and sulfur cycling. Notably, both active efflux/oxidative stress defense and indirect immobilization mechanisms were observed across all habitats, but their relative importance differed: FL and PA communities exhibited a greater reliance on active metal efflux (czcAB) and oxidative stress defense (trxAB) to maintain intracellular homeostasis, whereas SE communities displayed a stronger genomic potential for sulfate reduction (dsrAB) that may contribute to metal immobilization through sulfide precipitation. This metabolic partitioning highlights the complementary roles of different habitats in mediating metal toxicity and biogeochemical cycling, providing new insights into microbial resilience in polluted estuaries and underscoring the urgency of addressing heavy-metal contamination in these critical ecosystems.

Estuaries↗

Update of the Anopheles gambiae PEST genome assembly.

BACKGROUND: The genome of Anopheles gambiae, the major vector of malaria, was sequenced and assembled in 2002. This initial genome assembly and analysis made available to the scientific community was complicated by the presence of assembly issues, such as scaffolds with no chromosomal location, no sequence data for the Y chromosome, haplotype polymorphisms resulting in two different genome assemblies in limited regions and contaminating bacterial DNA. RESULTS: Polytene chromosome in situ hybridization with cDNA clones was used to place 15 unmapped scaffolds (sizes totaling 5.34 Mbp) in the pericentromeric regions of the chromosomes and oriented a further 9 scaffolds. Additional analysis by in situ hybridization of bacterial artificial chromosome (BAC) clones placed 1.32 Mbp (5 scaffolds) in the physical gaps between scaffolds on euchromatic parts of the chromosomes. The Y chromosome sequence information (0.18 Mbp) remains highly incomplete and fragmented among 55 short scaffolds. Analysis of BAC end sequences showed that 22 inter-scaffold gaps were spanned by BAC clones. Unmapped scaffolds were also aligned to the chromosome assemblies in silico, identifying regions totaling 8.18 Mbp (144 scaffolds) that are probably represented in the genome project by two alternative assemblies. An additional 3.53 Mbp of alternative assembly was identified within mapped scaffolds. Scaffolds comprising 1.97 Mbp (679 small scaffolds) were identified as probably derived from contaminating bacterial DNA. In total, about 33% of previously unmapped sequences were placed on the chromosomes. CONCLUSION: This study has used new approaches to improve the physical map and assembly of the A. gambiae genome.

Animals↗

[Conceptions and practices of community health agents caring for the elderly].

OBJECTIVE: To assess the main conceptions related to the aging process among community health agents. METHODS: An exploratory descriptive qualitative study was carried out in Pernambuco, Northeastern Brazil, from 2000 to 2002. Data was collected from records and interviews with 148 community health agents. The thematic analysis allowed data classification and assembling. RESULTS: The results show that community health agents identified their main tasks as the development of activities in health education and performance of basic actions. Most of them had negative opinions on the aging process, and complete understanding of the concept of health. They mentioned that most complaints by the elderly are health-related problems and need for affection. Community agents identified caring for the elderly as their main responsibility and inadequate service organization made it difficult to operationalize care delivery. Regarding their expectations, they were found to want to further their knowledge on the aging process. CONCLUSIONS: Community health agents identified themselves as main actors for delivery basic care and core agents in the accomplishment of specific health policies. Their conceptions had a positive perspective in relation to their attributions and aging health. The study points out to the need of promoting agents' training to make them able to deal with the multiple aspects of aging.

Adult↗

The issue of antimicrobial resistance in human medicine.

Antibiotics are used worldwide in human medicine and agriculture. In many cases the use of antibiotics is unnecessary or questionable. Consumption of antibiotics is linked to bacterial resistance. In hospitals, most common resistant bacteria include methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci and Gram-negative rods including Enterobacteriaceae and Pseudomonas aeruginosa. Vancomycin intermediate and resistant S. aureus, described just recently, represent a new treatment challenge. In the community, penicillin and macrolide-resistant pneumococci developed several decades ago and are now present all over the world. More recently, community-acquired methicillin-resistant S. aureus has become a problem in several countries causing skin infections but also severe diseases. Resistance to co-trimoxazole in Escherichia coli has changed empirical treatment of urinary tract infections, one of the most common causes of the visit to the physician's office. Several reports and studies trying to limit the use of antibiotics have shown that antimicrobial resistance of bacteria can be reversed, but in general the problem is far from being solved. World Health Assembly and the European Community Council have recognized the problem of antibiotic resistance as a priority. The relationship between agricultural use of antimicrobials and antibacterial resistance in humans should be further investigated.

Animals↗

Dynamics of soil fungal communities restored with biochar from a quarry site.

Quarrying activities have intensified due to population expansion, leading to landscape degradation and ecological destruction. Quarry restoration is usually mandatory in Hong Kong, China. Although biochar is used for sustainable soil amendment, its effectiveness in restoring quarry soil with poor properties has rarely been investigated. A 24-month field study was conducted to evaluate the ecological feasibility of restoring a quarry site by using native species (that is, Castanopsis fissa and Cyclobalanopsis edithiae) and biochar amendment. The results revealed that after 24 months, the application of biochar increased the organic carbon, phosphorus and potassium of the vegetated soil by at least 120 %, 31 % and 12 %, respectively, due to higher cation exchange capacity and better plant growth. The relative abundance of Ascomycota and Basidiomycota increased by 24 % and 47 % with biochar application when C. fissa was planted, which was likely associated with the improved nutrient cycling and soil fertility. Even though adding biochar to bare soil was found to increase the complexity of fungal co-occurrence networks, biochar application only increased fungal diversity in vegetated quarry soil but usually reduced its fungal richness. Moreover, fungal co-occurrence networks in vegetated soil became less complex, suggesting that biochar potentially helped plants to assemble specific, beneficial fungal communities. This effect is most pronounced in the soil planted with C. edithiae, where the structure of fungal communities after 24 months was significantly different from that at other restoration times. This study identifies key fungal phyla enhanced by biochar in quarry soil and provides an effective strategy for facilitating the restoration and management of degraded lands, especially quarry sites.

Charcoal↗