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PubMed1992

Hospital palliative care services: three models in three countries.

There is an increasing trend toward providing palliative care services within general hospitals. The history and work of three hospital palliative care teams is reviewed, one in New York, one in London, and one in Ontario, Canada. The evolution, leadership, structure, functioning, and financing of the teams is discussed. Indicators of success and survival, principally financial support, leadership, and acceptability within hospitals, are considered. It is recommended that the service traditionally limited to oncology patients be extended to other patient groups. It is also recommended that, taking into account cultural and institutional differences, standardized mechanisms be adopted so that services can be systematically audited and changes implemented. Research and education will become increasingly important if services within hospitals are to survive.

Hospices↗

PubMed2025

Long-term follow-up of children who received rapid genomic sequencing.

PURPOSE: To explore long-term trajectories of children who received rapid genome sequencing (RGS) in intensive care settings. METHODS: We examined the electronic health records of 67 critically ill pediatric patients who received RGS 6 to 8 years ago with a collective initial diagnostic yield of 46%. RESULTS: The median length of follow-up was 6.2 years (interquartile range 4.0-7.2 years). RGS-diagnosed patients had a longer average follow-up time compared with undiagnosed patients (5.9 years vs 4.8 years, P = .026) and more subspecialty appointments per follow-up year (9.4 vs 6.9, P = .036). Mortality during the follow-up period was 9%. Patients averaged 2.1 hospital readmissions per follow-up year and 28.1 hospitalized days per follow-up year. Forty-four patients (66%) had a documented new phenotype in the electronic health records during their follow-up period. Seven patients received clinician-driven reanalysis during the follow-up period, yielding 1 new diagnosis. Systematic reanalysis of RGS performed as part of this study identified 4 new candidate diagnoses. CONCLUSION: Pediatric patients who receive RGS during intensive care unit hospitalizations continue to be high health care utilizers in subsequent years, regardless of whether RGS identified a diagnosis. Additionally, two-thirds of this cohort had a documented phenotypic change over the follow-up period, indicating dynamic clinical evolution in the years after RGS.

Humans↗

PubMedDate not supplied

[Nursing Activity Score (NAS). Our experience with a nursing load calculation system based on times].

INTRODUCTION: The load calculation systems of nursing work in the ICU has not had the same success in its introduction as the prognostic survival estimation systems. It causes may be: a medical design not oriented towards nursing (Therapeutic Intervention Scoring System--TISS in all its versions), lack of adaptation to the calculating of staff (Nursing Manpower Use Score--NEMS, care levels) and demand for permanent technological up-dating. In 2003, NAS was published in an attempt to obviate all the problems expressed. Its result expresses the percentage of nursing work time required for attention to each patient. Our objective has been to apply the method in our ICU and evaluate its results. PATIENTS AND METHODS: During the last quarter of 2004, NAS was systematically applied to all the patients admitted to our ICU, regardless of the reason for admission and stay time in the Unit. The analysis of this application was done by SPSS/PC 11. RESULTS: NAS calculations of 350 patients, which represents 1880 total registers, were collected during the mentioned period. The NAS result of the first day was analyzed, 40.8 +/- 14.1, comparing it with its evolution during all the stay days of each patient, until reaching the ICU discharge date (39.3 +/- 12.7). The mean stay of our series has been 4.3 +/- 5.4 days during this period and the total accumulated NAS per patient was 196.2 +/- 279.8. There was no good correlation (R2: 0.273) between the NAS score on the first day of stay in the ICU but there was between total NAS and total stay of each case (R2: 0.958). Translated into times, this implies that one nurse can care for (by shift and average) 2.5 patients in our ICU. CONCLUSIONS: This system adapts, without demands of periodic up-dating, to the real nursing work in the ICU. Its design is oriented to nursing work, regardless of the disease that justifies admission to the ICU. It is useful to adequately evaluate the nursing staff in the conventional ICU.

Algorithms↗

PubMed2002

ASPM is a major determinant of cerebral cortical size.

One of the most notable trends in mammalian evolution is the massive increase in size of the cerebral cortex, especially in primates. Humans with autosomal recessive primary microcephaly (MCPH) show a small but otherwise grossly normal cerebral cortex associated with mild to moderate mental retardation. Genes linked to this condition offer potential insights into the development and evolution of the cerebral cortex. Here we show that the most common cause of MCPH is homozygous mutation of ASPM, the human ortholog of the Drosophila melanogaster abnormal spindle gene (asp), which is essential for normal mitotic spindle function in embryonic neuroblasts. The mouse gene Aspm is expressed specifically in the primary sites of prenatal cerebral cortical neurogenesis. Notably, the predicted ASPM proteins encode systematically larger numbers of repeated 'IQ' domains between flies, mice and humans, with the predominant difference between Aspm and ASPM being a single large insertion coding for IQ domains. Our results and evolutionary considerations suggest that brain size is controlled in part through modulation of mitotic spindle activity in neuronal progenitor cells.

Anthropometry↗

PubMed2003

Phylogeography of the Northern short-tailed shrew, Blarina brevicauda (Insectivora: Soricidae): past fragmentation and postglacial recolonization.

Blarina brevicauda is distributed across the northeastern region of North America, in areas previously covered by Pleistocene glaciers. Previous molecular systematic study of the species in the genus Blarina suggested the presence of two distinct eastern and western phylogroups within B. brevicauda, in agreement with traditionally recognized semi-species. To expand the previous work, a collection of 76 individuals from 14 localities collected throughout the range of B. brevicauda was used to assess the mitochondrial (mt) cytochrome b genealogy for this species. Minimum evolution, maximum parsimony, analysis of molecular variance and nested clade analysis each supported the same conclusions of two well-differentiated and monophyletic east-west groups, separated by the Mississippi River. Denser sampling in areas immediately East of the Mississippi basin revealed further subdivision within the eastern phylogroup into an East-Central and an Appalachian clade. The western phylogroup differed from the eastern phylogroup by 2.5% mean absolute DNA sequence difference. About 65% of the genetic variance among samples was explained by the east-west subdivision alone. High haplotype diversities, low nucleotide diversities and unimodal mismatch distributions within subclades suggest recent expansion or diversification within each group. No phylogeographic structure was found within the western phylogroup, but genetic structure because of restricted gene flow and isolation by distance was inferred for the eastern group. The present distribution of B. brevicauda is best explained by past fragmentation and range expansion events during and following the Pleistocene glacial cycles.

Animals↗

PubMed2000

Transformationalism, taxism, and developmental biology in systematics.

Issues concerning transformational and taxic comparisons are central to understanding the impact of the recent proliferation of molecular developmental data on evolutionary biology. More importantly, an understanding of taxism and transformationalism in comparative biology is critical to assessing the impact of the recent developmental data on systematic theory and practice. We examine the philosophical and practical aspects of the transformational approach and the relevance of this approach to recent molecular-based developmental data. We also examine the theoretical basis of the taxic approach to molecular developmental data and suggest that developmental data are perfectly amenable to the taxic approach. Two recent examples from the molecular developmental biology literature--the evolution of insect wings and the evolution of dorsal ventral inversion in vertebrates and invertebrates--are used to compare the taxic and transformational approaches. We conclude that the transformational approach is entirely appropriate for ontogenetic studies and furthermore can serve as an excellent source of hypotheses about the evolution of characters. However, the taxic approach is the ultimate arbiter of these hypotheses.

Animals↗

PubMed2006

Optimal intron analyses in the trimeresurus radiation of Asian pitvipers.

Nuclear introns are commonly used as phylogenetic markers, but a number of issues related to alignment strategies, indel treatments, and the incorporation of length-variant heterozygotes (LVHs) are not routinely addressed when generating phylogenetic hypotheses. Topological congruence in relation to an extensive mitochondrial DNA multigene phylogeny (derived from 2,423 bp of 12S, 16S, ND4, and CYTB genes) of the Asian pitviper Trimeresurus radiation was used to compare combinations of "by eye" and edited and unedited ClustalX 1.8 alignments of two nuclear introns. Indels were treated as missing data, fifth character states, and assigned simple and multistate codes. Upon recovery of the optimal alignment and indel treatment strategy, a total evidence approach was used to investigate the phylogenetic utility of the indels and test new generic arrangements within Trimeresurus. Approximately one third of the intron data partitions exhibited LVHs, suggesting that they are common in introns. Furthermore, a simple concatenation approach can facilitate the incorporation of LVHs into phylogenetic analyses to make use of all available data and investigate mechanisms of molecular evolution. Analyses of ClustalX 1.8-assisted alignments were generally more congruent than the "by eye" alignment and the analysis of a simple coded, edited ClustalX 1.8 (gap opening cost 5, gap extension cost 1) alignment revealed the most congruent tree. The total evidence approach supported the new arrangements within Trimeresurus, suggesting that the phylogeny should be considered as a working benchmark in Asian pitviper systematics. Finally, a critical appraisal of the diverse array of indels (56 to 57 per intron, ranging from 1 to 151 bp in length) suggested that they are a combination of Hennigian and homoplasious events unrelated to indel size or location within the intron. [Alignment; indels; intron analysis; length-variant heterozygotes; Trimeresurus.].

Animals↗

PubMed2001

Lattice Boltzmann equation hydrodynamics.

By inserting position and time dependent "source" or "forcing" terms into the microscopic evolution equation of a lattice Boltzmann fluid and treating the generalized scheme within the usual Chapman-Enskog methodology, we show that the emergent dynamics of the lattice fluid may be usefully transformed. Our method of adjustment is demonstrated by implementing the cylindrical polar coordinate form of the continuity and momentum equations on a rectangular lattice and generating results for pipe flow. With straightforward systematic adjustment of the simulation, our approach produces results in excellent agreement with theory.

Journal Article↗

PubMed2006

Unusually extensive karyotype reorganization in four congeneric Gerbillus species (Muridae: Gerbillinae).

Comparative analysis of the G- and C-banding patterns in four morphologically poorly differentiated Gerbillus species (G. pyramidum, G. perpallidus, G. tarabuli and G. occiduus) was carried out. These gerbils have similar karyotype morphology with 2n and NF equal to 38/76, 40/76, 40/78 and 40/80, respectively. Our study revealed that possibly 70 Robertsonian (Rb) fusions, two pericentric inversions, one tandem translocation and at least 13 non-identified rearrangements have occurred during the karyotypic evolution of these species. The number of chromosomal changes by which any of these species differ from each other ranges from 33 to 49. One Rb fusion was common to two of the species, with only a single autosome-gonosome translocation shared by all four, suggesting a monophyletic origin of these karyotypically highly divergent species. Based on the chromosomal data obtained here, the systematic and geographic implications for these North African species are also discussed.

Animals↗

PubMed2005

Anaplastic (undifferentiated) thyroid cancer: improved insight and therapeutic strategy into a highly aggressive disease.

BACKGROUND: This review article discusses the clinical and diagnostic implications of anaplastic thyroid cancer, recognizing the aggressive nature of the disease and extensive disease progression upon diagnosis. Standard treatment strategies (surgical, chemotherapy, radiation) are discussed, comparing adjuvant and neo-adjuvant regimens and the emergence of tumour resistance with expression of multidrug resistance pumps. We question the pathological evolution of anaplasia as a 'de novo' disease or a post malignant transformation or dedifferentiation and the therapeutic implications of p53 mutation. Future treatment options are reviewed with an emphasis on specific molecular targets responsible for the neoplastic phenotype. METHOD: An electronic search on Medline and Pubmed was performed under 'anaplastic thyroid carcinoma', 'anaplastic thyroid carcinogenesis', 'anaplastic thyroid carcinoma treatment reviews'. Relevant papers were systematically reviewed from 1965 to present.

Aged↗

PubMed2000

[Primary hyperparathyroidism].

Primary hyperparathyroidism is the third most frequent endocrine disorder. The condition required for diagnosis is inappropriately elevated secretion of parathyroid hormone (PTH) with respect to calcemia. Most often, the disease is due to a parathyroid adenoma, i.e. a monoclonal benign parathyroid tumor, less often to a parathyroid hyperplasia. The main tumorogenic mechanisms currently proposed are a DNA rearrangement in the PTH locus (transposition of the PTH promoter upstream to Cyclin D1/PRAD 1 gene) and a mutation of the gene responsible for multiple endocrine neoplasia type I. The clinical presentation has strikingly evolved towards a milder, asymptomatic form, frequently diagnosed on systematic screenings. Though the mechanism of hypercalcemia is better understood, several hypothesis are still being considered about the regulation of tumoral PTH secretion: the role of the expression of calcium-receptor in parathyroid gland cells, vitamin D receptor and estrogen receptor polymorphisms, etc. Surgery is still advised for symptomatic forms of the disease, either because of a bone involvement, or because of an evolutive nephrolithiasis. In the near future, the new calcium-receptor agonists could be a relevant therapeutic approach.

Humans↗

PubMed2006

[Abnormal clinical manifestations of dengue hemorrhagic fever in children].

INTRODUCTION: Recently, dengue hemorrhagic fever with unusual neurological and hepatic manifestations has been reported in children, with a concomitant increase in morbidity and mortality. OBJECTIVE: To describe unusual clinical manifestations of dengue hemorrhagic fever in children. MATERIALS AND METHODS: These manifestations were systematically scrutinized in dengue cases occurring between 1992-2004 in the Pediatrics Department of the University Hospital of Santander, Bucaramanga, Colombia. Case reports were examined of 913 patients with clinical symptoms of dengue hemorrhagic fever. They were classified according to standard criteria for dengue hemorrhagic fever and grouped according to the main organs or systems that were affected. Clinical presentation, laboratory results and medical evolution were summarized. RESULTS: Of the 913 cases, 168 showed abnormal clinical manifestations; these were predominant in male school age children and associated mainly with grades III and IV of dengue hemorrhagic fever. The most frequent manifestations were as follows: hepatitis--53 cases (27%), neurological alterations--49 (25%), renal impairment--14 (7%), cardiac involvement--15 (8%), pulmonary alterations--18 (9%), alithiasic cholecistitis--18 (9%), haemophagocitic syndrome--5 (2.5%), pancreatitis--2 (1%), and acute abdominal pain--21 (11%). Ten patients died. CONCLUSIONS: The results were compared with data from other endemoepidemic countries of dengue. The significance and importance of abnormal dengue were explored, as well as the difficult retrospective diagnoses. Hepatic and neurological manifestations were recognized as frequently involved in elevated morbidity and mortality. Physicians working in endemic zones should be aware of them in order to recognize them.

Adult↗

PubMedDate not supplied

[On the problem og higher fungi origin: Florideae hypothesis].

The history and current state of the hypothesis of the origin of higher fungi (Ascomycetes and Basidiomycetes) and red algae from the common ancestor (Florideae) were analysed. Initially the hypothesis was based on similarity of their vegetative and generative structures (Sachs, 1874; Dodge, 1914; Chadefaund, 1953, 1972, etc.), but later it was confirmed by ultrastructural data (Demoulin, 1974; Kohlmeyer, 1975). It appears to be very useful for the study of the development of terrestrial flora (Church, 1921; Kohlemeyer, Kohlmeyer, 1979; Atsatt, 1988) and regularities in morphological evolution of higher fungi (Corner, 1964, 1970; Chadefaud, 1960, 1982, 1984). Description of the order Spathulosporales (Kohlmeyer, 1973), combining the characters of Ascomycetes and parasitic Florideae, was one of the most important fact leading to the wide recognition of the hypothesis in 1970-80s (Cavalier-Smith, 1978; Taylor, 1978; Dodge, 1980; Hawksworth, 1982; Goff, 1983; Coff, Coleman, 1985). Today, however, Florideae hypothesis is not confirmed by molecular data and replaced by alternative hypothesis of Eumycota origin. Summarizing data on molecular systematic of fungi, one could affirm with confidence: 1). Chitincontaining fungi are closer to multicellular animals and green plants than to Rhodophyta; 2). Rhodophyta and Chlorophyta are monophyletic group; 3). There is no single-valued molecular data on taxonomic distance between higher fungi, Chytridiomycetes; Rhodophyta, Chlorophyta and Metazoa. Thus, the current data could not testify against Florideae hypothesis. It is possible to adjust them with the idea of B.M. Kozo-Polyansky (1927) about existence of "Chloroflorodeae" group that is original for terrestrial flora; the hypothesis about closeness of Chlorophyta and Rhodophyta, as well as Chlorophyta and Eumycota, does not contradict molecular data (Stiller, Hall, 1997). The author believes that we need molecular study of the whole "stem" of chlorobionta, especially groups that are close to its basis. It will will help to understand the relationships between Rhodophyta, giant conglomeration of "green algae", chitin-containing fungi, Prasinophyceae and different groups of zoomastigot with maximal resolution--the level of orders or groups of orders. Only such investigation could provide the material for molecular support of phylogenetic constructions. Up to moment Florideae hypothesis is able to exist together with the other ideas.

Ascomycota↗

PubMed2005

Systematic repeat addition at a precise location in the coding region of the involucrin gene of wild mice reveals their phylogeny.

The involucrin gene encodes a protein of terminally differentiated keratinocytes. Its segment of repeats, which represents up to 80% of the coding region, is highly polymorphic in mouse strains derived from wild progenitors. Polymorphism includes nucleotide substitutions, but is most strikingly due to the recent addition of a variable number of repeats at a precise location within the segment of repeats. Each mouse taxon examined showed consistent and distinctive patterns of evolution of its variable region: very rapid changes in most M. m. domesticus alleles, slow changes in M. m. musculus, and complete arrest in M. spretus. We conclude that changes in the variable region are controlled by the genetic background. One of the M. m. domesticus alleles (DIK-L), which is of M. m. musculus origin, has undergone a recent repeat duplication typical of M. m. domesticus. This suggests that the genetic background controls repeat duplications through trans-acting factors. Because the repeat pattern differs in closely related murine taxa, involucrin reveals with greater sensitivity than random nucleotide substitutions the evolutionary relations of the mouse and probably of all murids.

Alleles↗

PubMed2003

From the operating room of the present to the operating room of the future. Human-factors lessons learned from the minimally invasive surgery revolution.

The minimally invasive surgical revolution has changed the way surgery is practiced. It has also helped surgical innovators to break the tethers that anchored the practice of surgery in an early 20th century operating room environment. To some in surgery, the Operating Room of the Future will be seen as a revolution but to others, an inevitable evolution of the changes ushered in by the adoption of minimally invasive surgery. Although minimally invasive surgery has conferred considerable advantages on the patient, it has imposed significant difficulties on the surgeon, which in turn, have impacted outcomes. These difficulties were primarily human factor in nature and were poorly understood by critical groups such as device manufacturers, surgeons, and surgery educators and trainers. This article details what these human factors were, how they related to the practice of minimally invasive surgery, and how they will impact on the practice of surgery in the Operating Room of the Future. Much of the technology for the Operating Room of the Future currently exists (eg, surgical robotics, virtual reality, and telemedicine). However, for it to function optimally it must be integrated in a fashion that takes on board the human factor strengths and limitations of the surgeon. These advanced technologies should then be harnessed to optimize surgical practice. In some cases, this will involve rethinking existing technologies (ie, three-dimensional camera systems), applying technologies that currently exist in a manner that is more systematic and better managed (ie, surgical robots and virtual reality), and a reconsideration of who should be applying these technologies for the practice of surgery in the 21st century. In all cases, there will be education and training implications for the practitioner. Lastly, there must be unequivocal demonstration that these changes bring about positive benefits for patients in terms of better outcomes and for surgeons in terms of ability and ease of doing their job. After the experiences of the last decade with minimally invasive surgery, the Operating Room of the Future should be seen as a well-grounded evolution, not a revolution.

Human Characteristics↗

PubMed2001

A Paedomorphic parasite associated with a neotenic amphibian host: phylogenetic evidence suggests a revised systematic position for Sphyranuridae within anuran and turtle Polystomatoineans.

The phylogenetic relationships of the families Polystomatidae and Sphyranuridae (subclass Polystomatoinea) within tetrapod monogenean parasites were investigated using partial 18S rDNA sequences. About 600 nucleotides of 11 species were sequenced, including 7 species of the most common subfamilies of Polystomatidae found in anurans and turtles, 1 species of the family Sphyranuridae parasitizing exclusively urodelans, and 3 species of the subclass Oligonchoinea infesting teleostean fishes. The phylogenetic analyses were performed using three reconstruction methods: neighbor-joining, maximum-parsimony, and maximum-likelihood. Polystomatoineans but not polystomatids were shown to be monophyletic. Within the polystomatoineans there are two clades: one includes the amphibian monogeneans (anuran polystomatids and urodelan sphyranurids) and the other includes the turtle polystomatids. Polystomatoineans may have coevolved with amphibian hosts, and an ancestral "polystome" dispersed at least 200 million years ago, either from the basal stem of lissamphibians or from an anuran ancestral stock, to freshwater turtles. Furthermore, the urodelan genus Sphyranura, initially assigned to the family Sphyranuridae on the basis of morphological and ontogenetic evidence, is clearly nested within polystomatids, suggesting that its systematic status must be revised. This supports recent findings which argue that species of the family Sphyranuridae may be paedomorphic parasites exclusively infesting neotenic mudpuppies.

Animals↗

PubMed2026

Integrating genomic distance analyses in the description of a new family, genus, and species of sponge-associated antipatharians (black corals).

Antipatharians (black corals) are among the least studied coral groups, with much of their diversity still undescribed. Here, we present an integrative morphological, phylogenomic and genomic distance study of deep-sea antipatharians sampled in high seas areas of the North Pacific Ocean and from New Zealand's Exclusive Economic Zone. These corals grow on hexactinellid sponges - a unique characteristic in the order Antipatharia. Using a dataset of ultra-conserved elements and exons, combined with morphological analyses, we reconstruct phylogenomic relationships and formally describe a new family (Eidikopathidae fam. nov.), a new genus (Eidikopathesgen. nov.), and two new species (E. korallispongiasp. nov., E. zealandkoralliasp. nov.). Morphologically, the new family is distinguished by a corallum consisting of a network of loose branches that fuse with the sponge skeletal framework. Phylogenomic analyses recovered consistent topologies with strong nodal support, corroborating the distinct evolutionary placement of this sponge-associated lineage. Pairwise genomic distances estimated using the Tamura-Nei model were concordant with patristic genomic distances, identifying Pteridopathidae as the genetically closest family to Eidikopathidae fam. nov., followed by Myriopathidae and Stylopathidae, which were recovered as sister families in the phylogeny. This pattern shows that genomic distance complements, rather than simply mirrors, tree topology by quantifying accumulated sequence divergence among lineages. Together, these results provide the first genomic distance framework for Antipatharia, offering a baseline for future systematic, evolutionary, and biodiversity studies on this fundamental shallow, mesophotic and deep-sea coral group.

Animals↗

PubMed2006

Seed dormancy and delayed flowering in monocarpic plants: selective interactions in a stochastic environment.

We explore the effects of temporal variation in multiple demographic rates on the joint evolution of delayed reproduction and seed dormancy using integral projection models (IPMs). To do this, we extend the standard IPM to include a discrete state variable representing the number of seeds in the seed bank, density-dependent recruitment, and temporal variation in demography. Parameter estimates for Carlina vulgaris and Carduus nutans are obtained from long-term studies. Carlina is relatively long lived and has a short-lived seed bank, whereas most Carduus plants flower in their first year and the seed bank is long lived. Using the evolutionarily stable strategy (ESS) approach, we predict the observed flowering and germination strategies. There is excellent agreement between the predictions and the field observations. The effects of temporal variation on the joint ESS are partitioned into components arising from nonlinear averaging (systematic changes in the mean resulting from the interaction between variability and nonlinearity) and nonequilibrium dynamics (fluctuations in fitness caused by temporal variation). This shows that temporal variation can have substantial effects on the observed flowering and germination strategies and that covariance between demographic processes is important. We extend the models to include spatial population structure and assess the robustness of the results from the nonspatial models.

Asteraceae↗