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PubMed2004

Heightened condition dependence is not a general feature of male eyespan in stalk-eyed flies (Diptera: Diopsidae).

Stalk-eyed flies are exemplars of sexual selection leading to the evolution of exaggerated male ornaments (eyespan). In Sphyracephala beccarri, there is no evidence for female mate choice for exaggerated male eyespan and only minor sex differences in eyespan. We used S. beccarri to test whether heightened condition dependence only evolves when male eyespan becomes sexually exaggerated. Male eyespan showed heightened condition dependence under food stress compared with a control trait (wing length). However, female eyespan displayed a similar pattern and there was no sex difference in the degree of increased eyespan sensitivity. The finding that eyespan is a sensitive indicator of food stress, even in an unexaggerated state, suggests that this may have acted as a pre-adaptation to the role of eyespan in sexual signalling in other Diopsid species. These results are consistent with handicap theory and Fisher's view of how sexual selection is initiated.

Analysis of Variance↗

PubMed2005

Crises in clinical care: an approach to management.

A "crisis" in health care is "the point in the course of a disease at which a decisive change occurs, leading either to recovery or to death". The daunting challenges faced by clinicians when confronted with a crisis are illustrated by a tragic case in which a teenage boy died after a minor surgical procedure. Crises are challenging for reasons which include: presentation with non-specific signs or symptoms, interaction of complex factors, progressive evolution, new situations, "revenge effects", inadequate assistance, and time constraints. In crises, clinicians often experience anxiety- and overload-induced performance degradation, tend to use "frequency gambling", run out of "rules" and have to work from first principles, and are prone to "confirmation bias". The effective management of crises requires formal training, usually simulator-based, and ideally in the inter-professional groups who will need to function as a team. "COVER ABCD-A SWIFT CHECK" is a pre-compiled algorithm which can be applied quickly and effectively to facilitate a systematic and effective response to the wide range of potentially lethal problems which may occur suddenly in anaesthesia. A set of 25 articles describing additional pre-compiled responses collated into a manual for the management of any crisis under anaesthesia has been published electronically as companion papers to this article. This approach to crisis management should be applied to other areas of clinical medicine as well as anaesthesia.

Algorithms↗

PubMed2006

Fluorescent amplified fragment length polymorphism (FAFLP) genotyping demonstrates the role of biofilm-producing methicillin-resistant periocular Staphylococcus epidermidis strains in postoperative endophthalmitis.

BACKGROUND: An observational case series was used to study the virulence characteristics and genotypes of paired Staphylococcus epidermidis isolates cultured from intraocular samples and from periocular environment of patients with postcataract surgery endophthalmitis. METHODS: Eight S. epidermidis isolates were obtained from three patients (2 from patients #1 and 2 and 4 from patient #3) whose vitreous and/or anterior chamber (AC) specimens and preoperative lid/conjunctiva samples were culture positive. Cultures were identified by API-Staph phenotypic identification system and genotypically characterized by Fluorescent Amplified Fragment Length Polymorphism (FAFLP) and checked for their antimicrobial susceptibility. The isolates were tested for biofilm-production and methicillin-resistance (MR) by PCR amplification of icaAB and mecA gene respectively. RESULTS: Four out of eight S. epidermidis strains showed multiple drug resistance (MDR). All the eight strains were PCR positive for mecA gene whereas seven out of eight strains were positive for icaAB genes. In all three patients FAFLP typing established vitreous isolates of S. epidermidis strains to be indistinguishable from the strains isolated from the patient's conjunctival swabs. However, from patient number three there was one isolate (1030b from lid swab), which appeared to be nonpathogenic and ancestral having minor but significant differences from other three strains from the same patient. This strain also lacked icaAB gene. In silico analysis indicated possible evolution of other strains from this strain in the patient. CONCLUSION: Methicillin-resistant biofilm positive S. epidermidis strains colonizing the conjunctiva and eyelid were responsible for postoperative endophthalmitis (POE).

Adult↗

PubMed2004

Domain shuffling has been the main mechanism forming new hominoid killer cell Ig-like receptors.

The killer cell Ig-like receptor (KIR) gene family encodes MHC class I-specific receptors, which regulate NK cell responses and are also expressed on subpopulations of T cells. KIR haplotypes vary in gene content, which, in combination with allelic polymorphism, extensively diversifies the KIR genotype both within and between human populations. Species comparison indicates that formation of new KIR genes and loss of old ones are frequent events, so that few genes are conserved even between closely related species. In this regard, the hominoids define a time frame that is particularly informative for understanding the processes of KIR evolution and its potential impact on killer cell biology. KIR cDNA were characterized from PBMC of three gorillas, and genomic DNA were characterized for six additional individuals. Eleven gorilla KIR genes were defined. With attainment of these data, a set of 75 KIR sequences representing five hominoid species was assembled, which also included rhesus monkey, cattle, and rodent KIR. Searching this data set for recombination events, and phylogenetic analysis using Bayesian methods, demonstrated that new KIR were usually the result of recombination between loci in which complete protein domains were shuffled. Further phylogenetic analysis of the KIR sequences after removal of confounding recombined segments showed that only two KIR genes, KIR2DL4 and KIR2DL5, have been preserved throughout hominoid evolution, and one of them, KIR2DL4, is also common to rhesus monkey and hominoids. Other KIR genes represent recombinant forms present in a minority of species, often only one, as exemplified by 8 of the 11 gorilla KIR genes.

Animals↗

PubMedDate not supplied

[Changes in cerebra serotonin synthesis induced by insulin-dependent diabetes mellitus].

OBJECTIVE: Evaluate if the rats with diabetes mellitus insulin-dependent have a minor activity of the serotonergic biosynthetic pathway through the decrease of the free fraction of L-tryptophan in plasma. METHODS: Diabetes mellitus was induced in rats, and the brain serotonergic biosynthetic activity was evaluated at 7, 14, and 21 days after streptozotocin administration. RESULTS: The diabetic animals showed a general decrease in body weight. In plasma they had a decrease in the free fraction of L-tryptophan. Also, in the brain they show low levels of the amino acid, as well as decrease of the activity of the limiting enzyme tryptophan-5-hydroxylase and its product serotonin. Interestingly, the activity of the enzyme was higher in the brainstem from day 14, accompanied with an elevation of the neurotransmitter. CONCLUSIONS: The results confirm that diabetes mellitus insulin-depend induce chronic undernourishment. The low levels of L-tryptophan in blood of the diabetic animals suggest a minor transport of the amino acid to the brain and a decrease in serotonin synthesis, in cerebral cortex and hypothalamus. Besides, during the evolution of the disease, the activity of tryptophan hydroxylase was elevated, independently of L-tryptophan concentration in the brainstem of diabetic animals, suggesting a different response according to the brain region and possibly a different functional change, accompanied by an increase in the synthesis of the neurotransmitter.

Animals↗

PubMed1986

Hyperthyroidism and the heart: study of left ventricular function in preclinical hyperthyroidism.

To study the response of the target organs to minor increments of thyroid hormone levels, left ventricular ejection fraction (LVEF) the primary indicator of left ventricular function, was measured in patients with preclinical hyperthyroidism and the results were compared with those obtained in euthyroid subjects and in patients with toxic adenoma. In euthyroid subjects and in patients with preclinical hyperthyroidism LVEF in response to exercise involving an isometric static work load revealed a minor increase, whereas in manifest hyperthyroidism (toxic adenoma) an opposite response with an impairment of left ventricular functional capacity was found. The results showed that the pituitary responds more sensitively to minor changes in the circulating thyroid hormone levels than does the heart and indicated that the typical hyperthyroid heart changes associated with the evolution of toxic adenoma develop gradually.

Adenoma↗

PubMed1979

[Chronic depressions (author's transl)].

The definition of chronic depression necessarily calls for a review of the concept of recovery which in psychopathology is not clearly and univocally defined. The percentage of chronic evolution among depressive patients either as a persistence of depressive symptoms or as an impairment of social and professional role, ranges from 12 to 15%. Chronic depression raises psychopathologic and nosographic problems as well as clinical ones. In fact chronic depressives are often not correctly diagnosed, inadequately treated and destined to be affected by an over increasing inability. The chronic evolution of depression may result as a concurrence of several factors: a neurotic personality, an inadequate antidepressant maintenance treatment, an inappropriated use of minor tranquillizers as the only treatment. The occurrence of physical impairement, the continuous nature of depression and the resistance of antidepressant treatment may be also considered. Moreover the psychodynamic mechanisms aroused by the depressive experience and the secondary advantages of the illness may plan an effective role maintaining depressive symptomatology.

Bipolar Disorder↗

PubMed1996

Structure optimization of an artificial neural filter detecting membrane-spanning amino acid sequences.

An artificial neural network has been developed for the recognition and prediction of transmembrane regions in the amino acid sequences of human integral membrane proteins. It provides an additional prediction method besides the common hydrophobicity analysis by statistical means. Membrane/nonmembrane transition regions are predicted with 92% accuracy in both training and independent test data. The method used for the development of the neural filter is the algorithm of structure evolution. It subjects both the architecture and parameters of the system to a systematical optimization process and carries out local search in the respective structure and parameter spaces. The training technique of incomplete induction as part of the structure evolution provides for a comparatively general solution of the problem that is described by input-output relations only. Seven physiochemical side-chain properties were used to encode the amino acid sequences. It was found that geometric parameters like side-chain volume, bulkiness, or surface area are of minor importance. The properties polarity, refractivity, and hydrophobicity, however, turned out to support feature extraction. It is concluded that membrane transition regions in proteins are encoded in sequences as a characteristic feature based on the respective side-chain properties. The method of structure evolution is described in detail for this particular application and suggestions for further development of amino acid sequence filters are made.

Algorithms↗

PubMed2004

Evolution of the RNA polymerase B' subunit gene (rpoB') in Halobacteriales: a complementary molecular marker to the SSU rRNA gene.

Many prokaryotes have multiple ribosomal RNA operons. Generally, sequence differences between small subunit (SSU) rRNA genes are minor (<1%) and cause little concern for phylogenetic inference or environmental diversity studies. For Halobacteriales, an order of extremely halophilic, aerobic Archaea, within-genome SSU rRNA sequence divergence can exceed 5%, rendering phylogenetic assignment problematic. The RNA polymerase B' subunit gene (rpoB') is a single-copy conserved gene that may be an appropriate alternative phylogenetic marker for Halobacteriales. We sequenced a fragment of the rpoB' gene from 21 species, encompassing 15 genera of Halobacteriales. To examine the utility of rpoB' as a phylogenetic marker in Halobacteriales, we investigated three properties of rpoB' trees: the variation in resolution between trees inferred from the rpoB' DNA and RpoB' protein alignment, the degree of mutational saturation between taxa, and congruence with the SSU rRNA tree. The rpoB' DNA and protein trees were for the most part congruent and consistently recovered two well-supported monophyletic groups, the clade I and clade II haloarchaea, within a collection of less well resolved Halobacteriales lineages. A comparison of observed versus inferred numbers of substitution revealed mutational saturation in the rpoB' DNA data set, particularly between more distant species. Thus, the RpoB' protein sequence may be more reliable than the rpoB' DNA sequence for inferring Halobacteriales phylogeny. AU tests of tree selection indicated the trees inferred from rpoB' DNA and protein alignments were significantly incongruent with the SSU rRNA tree. We discuss possible explanations for this incongruence, including tree reconstruction artifact, differential paralog sampling, and lateral gene transfer. This is the first study of Halobacteriales evolution based on a marker other than the SSU rRNA gene. In addition, we present a valuable phylogenetic framework encompassing a broad diversity of Halobacteriales, in which novel sequences can be inserted for evolutionary, ecological, or taxonomic investigations.

Base Sequence↗

PubMed2001

Rice--the pivotal genome in cereal comparative genetics.

Over the past 15 years rice has been the focus of intense co-ordinated research activity to apply the new molecular biology to this key staple. The fact that rice has a small tractable genome and the development of genetic and genomic tools not available in any other cereal have now ensured the promotion of rice as a favoured research target. However the discovery that gene content and gene order--genome colinearity--have been maintained among all the Poaceae family for some 60 million years of evolution has elevated rice yet further to the status of a 'model' organism. Rice tools can be applied in research on the other major cereals, wheat and maize, and many aspects of rice genetics can be transferred to the many minor economic grass species that have not themselves warranted extensive research and breeding. In this paper we describe some of the applications of the discovery of extensive synteny among the grasses.

Biological Evolution↗

PubMed1999

[The appearance of giant negative T waves in anterior acute myocardial infarct with a Q wave is associated with minor myocardial damage and a minor extension of coronary disease].

INTRODUCTION AND OBJECTIVE: The early inversion of T waves in patients with acute myocardial infarction has recently been related to a better left ventricular function and a more favourable evolution, contrary to what happens in the unstable angina. On the other hand, the significance of the appearance of deep negative T waves in the early phase of some acute myocardial infarction is not known. The aim of this study is to evaluate its relation with the existing myocardial damage and the underlying coronary artery disease extension in anterior some with Q wave. METHODS: 48 patients with a first anterior Q-wave acute myocardial infarction, thrombolized or not, admitted to hospital with an evolution of less than 24 hours, and with a coronariography performed before discharge were analyzed. Giant negative T waves were defined as those which were 8 mm or more from baseline. RESULTS: 17 of the 48 patients presented giant negative T waves (T-group) and 31 did not (N-group). In the T-group patients, the size of the negative T wave was 11.29 +/- 2.86 mm and the number of precordial leads with negative T waves was 4.35 +/- 1.57. There were no differences between both groups in variables such as sex, coronary risk factors, and other basal characteristics. The T-group patients were younger, had lower peak-CK, CK-MB and LDH levels and presented greater recovery of R waves during the follow-up, the differences being significant with the N-group patients. The left ventricular ejection fraction was higher (56.3 +/- 13.4 vs 42 +/- 12%; p < 0.001) and the number of affected coronary vessels was lower in the T-group (1.12 vs 1.64; p < 0.01); there were no differences in the localization or severity of coronary lesions, nor in the frequency of postinfarction myocardial angina. None of the patients in the T-group were Killip > I, while this situation occurred in 38.7% of the N-group patients. CONCLUSIONS: The appearance of giant negative T waves in the acute or early phase of Q-wave anterior acute myocardial infarction is associated with a smaller infarct size, lower functional deterioration and less extension of the underlying coronary disease.

Adult↗

PubMed1995

The history and evolution of surgical instruments. VI. The surgical blade: from finger nail to ultrasound.

Elective surgery requires planned incisions and incisions require appropriate blades. In the prehistoric era, division of the umbilical cord and other minor procedures were probably undertaken with human teeth and nails, and later with plant, animal and mineral substitutes, as witnessed by studies of primitive societies still surviving or recently extinct. More efficient metallic blades appeared in historic times and ultimately generated five specific shapes which are analysed in detail. Today, as minimally invasive techniques, endoscopes, laser and ultrasound sources evolve, many hallowed incisions of surgical access diminish in length or disappear entirely. In historical terms, elective surgery of the twentieth century will be recalled as an interlude characterised by maximally invasive incisions.

Equipment Design↗

PubMed1983

Two cases of acute leukemia following treatment of malignant glioma.

Two female patients, 42 and 30 years old, respectively, died of acute nonlymphocytic leukemia 43 and 38 months, respectively, after a subsequent treatment: chemotherapy for one and irradiation and chemotherapy for the other, following excision of a malignant glioma. At the time of death, both seemed to be in complete remission of their brain tumor. Both had been treated with procarbazine and nitrosoureas. The latter were responsible for severe myelosuppressive episodes and seem to have played an essential role in the induction of the leukemia. In one case, a myelodysplasia was observed before the onset of the AL and the diagnosis of refractory anemia with excess of blasts seemed warranted. Secondary acute leukemias are rare in the evolution of malignant gliomas and the usefulness of subsequent radiochemotherapy cannot be questioned at the present time. The risks involved in this therapy are minor when compared to the short-term fatal prognosis of this type of tumor.

Acute Disease↗

PubMed2004

Geographic distribution of environmental factors influencing human skin coloration.

Skin coloration in indigenous peoples is strongly related to levels of ultraviolet radiation (UVR). In this study, the relationships of skin reflectance to seasonal UVR levels and other environmental variables were investigated, with the aim of determining which variables contributed most significantly to skin reflectance. The UVR data recorded by satellite were combined with environmental variables and data on human skin reflectance in a geographic information system (GIS). These were then analyzed visually and statistically through exploratory data analysis, correlation analysis, principal components analysis, least-squares regression analysis, and nonlinear techniques. The main finding of this study was that the evolution of skin reflectance could be almost fully modeled as a linear effect of UVR in the autumn alone. This linear model needs only minor modification, by the introduction of terms for the maximum amount of UVR, and for summer precipitation and winter precipitation, to account for almost all the variation in skin reflectance. A further significant finding was that the effect of summer UVR seems to reach a threshold beyond which further adaptation is difficult.

Environmental Exposure↗

PubMed2000

Middle paleolithic human deciduous incisor from Khudji, Tajikistan.

In 1997 a human mandibular second deciduous incisor was discovered during excavations at the central Asian Middle Paleolithic site of Khudji, Tajikistan. The specimen was associated with a late Middle Paleolithic assemblage in a minimally disturbed cultural layer. The specimen is average in size for Late Pleistocene archaic human di(2)s and differs from many late archaic human di(2)s in having minimal marginal ridges and tapering markedly distally. In these features it resembles a minority of specimens from the later Pleistocene.

Animals↗

PubMed2006

Human endogenous retrovirus HERV-H family in human tissues and cancer cells: expression, identification, and phylogeny.

HERV-H family is the most abundant HERV families in the human genome with more than 1000 copies including full-length, truncated form, and solitary LTRs. We investigated envelope (env) gene fragments of HERV-H family in various human tissues and cancer cells. The env fragments were detected in mRNA of several human tissues (placenta, skeletal muscle, spleen, and thymus) and cancer cells (RT4, BT-474, HCT-116, TE-1, UO-31, Jurkat, HepG2, A549, MCF7, OVCAR-3, MIA-PaCa-2, PC3, LOX-IMVI, AZ521, 2F7, U-937, and C-33A) by RT-PCR approach. The RT-PCR products were cloned and sequenced. New 12 clones from human tissues and 48 clones from cancer cells of env gene sequences belonging to the HERV-H family showed 84.3-98.1% sequence similarity to that of HERV-H (AF108843). Deduced amino acid sequences of 60 clones from human tissues and cancer cell lines showed multiple frameshifts and termination codons caused by deletion/insertion or point mutation with the exception of eight clones as following: HHE9-1, HHE9-5 (skeletal muscle), HHE10-5 (spleen), CHE10-9 (MCF7), CHE12-4, CHE12-5 (MIA-PaCa-2), and CHE18-1, CHE18-3 (C-33A) to that of HERV-H (AF108843). A phylogenetic tree of the HERV-H family was constructed to understand their relationship, indicating that they were divided into three groups, one major (group I) and two minor (group II and III), through sequence divergence. The HERV-H families in group I has been proliferated on human genome during hominoid evolution. These active HERV-H elements are worthy of further investigations as potential pathogenic effects to various human diseases including cancers.

Amino Acid Sequence↗

PubMed2002

[The surgical treatment of liver metastasis of carcinoid tumors].

Liver metastasis of carcinoid tumors from the digestive tract are rare entities, with characteristic symptoms and slow evolution. Symptomatic metastases may justify surgical resection. Herein, we report a series of nine patients, who underwent 14 hepatic resections (6 major and 8 minor), which was radically operated in 71%. The postoperative mortality was zero and the morbidity was 7%. Mean follow-up was 82 month (median 75 months) and global survival rate was 89%. Two patients are in complete remission. Our experience suggest that surgical hepatic resection, when feasible, is efficient and associated with prolonged survival despite a high recurrence rate.

Adult↗

PubMed2005

Structure, bonding, and magnetism in manganese clusters.

We investigate the structures and magnetic properties of small Mn(n) clusters in the size range of 2-13 atoms using first-principles density functional theory. We arrive at the lowest energy structures for clusters in this size range by simultaneously optimizing the cluster geometries, total spins, and relative orientations of individual atomic moments. The results for the net magnetic moments for the optimal clusters are in good agreement with experiment. The magnetic behavior of Mn(n) clusters in the size range studied in this work ranges from ferromagnetic ordering (large net cluster moment) for the smallest (n=2, 3, and 4) clusters to a near degeneracy between ferromagnetic and antiferromagnetic solutions in the vicinity of n=5 and 6 to a clear preference for antiferromagnetic (small net cluster moment) ordering at n=7 and beyond. We study the details of this evolution and present a picture in which bonding in these clusters predominantly occurs due to a transfer of electrons from antibonding 4s levels to minority 3d levels.

Journal Article↗