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PubMed2006

Acute partial Budd-Chiari syndrome and portal vein thrombosis in cytomegalovirus primary infection: a case report.

BACKGROUND: Splanchnic vein thrombosis may complicate inherited thrombotic disorders. Acute cytomegalovirus infection is a rare cause of acquired venous thrombosis in the portal or mesenteric territory, but has never been described extending into a main hepatic vein. CASE PRESENTATION: A 36-year-old immunocompetent woman presented with acute primary cytomegalovirus infection in association with extensive thrombosis in the portal and splenic vein. In addition, a fresh thrombus was evident in the right hepatic vein. A thorough evaluation for a hypercoagulable state was negative. The clinical course, biological evolution, radiological and histological findings were consistent with cytomegalovirus hepatitis complicated by a partial acute Budd-Chiari syndrome and portal thrombosis. Therapeutic anticoagulation was associated with a slow clinical improvement and partial vascular recanalization. CONCLUSION: We described in details a new association between cytomegalovirus infection and acute venous thrombosis both in the portal vein and in the right hepatic vein, realizing a partial Budd-Chiari syndrome. One should be aware that this rare thrombotic event may be complicated by partial venous outflow block.

Acute Disease↗
PubMed2006

Nutrition rehabilitation of undernourished children utilizing Spiruline and Misola.

BACKGROUND: Malnutrition constitutes a public health problem throughout the world and particularly in developing countries. AIMS: The objective of the study is to assess the impact of an elementary integrator composed of Spiruline (Spirulina platensis) and Misola (millet, soja, peanut) produced at the Centre Medical St Camille (CMSC) of Ouagadougou, Burkina Faso, on the nutritional status of undernourished children. MATERIALS AND METHODS: 550 undernourished children of less than 5 years old were enrolled in this study, 455 showed severe marasma, 57 marasma of medium severity and 38 kwashiorkor plus marasma. We divided the children randomly into four groups: 170 were given Misola (731 +/- 7 kcal/day), 170 were given Spiruline plus traditional meals (748 +/- 6 kcal/day), 170 were given Spiruline plus Misola (767 +/- 5 kcal/day). Forty children received only traditional meals (722 +/- 8 kcal/day) and functioned as the control group. The duration of this study was eight weeks. RESULTS AND DISCUSSION: Anthropometrics and haematological parameters allowed us to appreciate both the nutritional and biological evolution of these children. The rehabilitation with Spiruline plus Misola (this association gave an energy intake of 767 +/- 5 kcal/day with a protein assumption of 33.3 +/- 1.2 g a day), both greater than Misola or Spiruline alone, seems to correct weight loss more quickly. CONCLUSION: Our results indicate that Misola, Spiruline plus traditional meals or Spiruline plus Misola are all a good food supplement for undernourished children, but the rehabilitation by Spiruline plus Misola seems synergically favour the nutrition rehabilitation better than the simple addition of protein and energy intake.

Arachis↗
PubMed2005

Eighty years ago.

Explore the source record for details and available documents.

Biological Evolution↗
PubMed2006

Aging is no longer an unsolved problem in biology.

For much of the 20th century, the accumulation of a considerable amount of information about the processes of aging did not reveal the underlying mechanisms. Toward the end of that century, the biological basis for aging became very much clearer. It became apparent that the best strategy for animals' survival was to develop to an adult, but not to invest resources in maintaining the body, or soma, indefinitely. In their natural environment, animals do not survive environmental hazards (predators, disease, starvation, and drought) to reach a long life span. There is thus a trade-off between the investment of resources in reproduction, and the survival time of the soma. At a stroke, this solves the problem of different rates of aging in different species, because those that develop and reproduce fast also have short life spans, and those that develop and reproduce slowly have long life spans. This difference is due to actual resources invested in the maintenance of the adult soma. There is now much evidence that long-lived mammals have much more efficient maintenance mechanisms than short-lived mammals. Thus, aging can be defined as the eventual failure of maintenance. It also became apparent that many different maintenance mechanisms exist, and that these depend on very many genes and a considerable investment in metabolic resources. Most individual theories of aging revolve around the failure of a given maintenance system, but as there are many of these, it is likely that most of the important theories have some degree of truth. A broad interpretation of the different degenerative changes during senescence should therefore be adopted, with the major conclusion that aging is multicausal. It is also evident that the evolved design of many components of complex animals is incompatible with indefinite survival. We can therefore conclude that this evolved design is intrinsically related to the fact of aging. This in turn means that aging cannot be reversed, although it may be modulated, as, for example, by calorie restriction.

Aging↗
PubMed1990

Plasma transport of the 20,000-dalton variant of human growth hormone (20K): evidence for a 20K-specific binding site.

The 20,000-dalton variant of human GH (20K) is known to circulate in blood, but few details are known about its plasma transport. A substantial portion of 20K appears to be protein bound despite its low affinity for the receptor-related GH-binding protein (BP). We, therefore, investigated the binding pattern of 20K in human plasma. Radioiodinated 20K was incubated with plasma or plasma fractions, and the mixture was fractionated by gel filtration. Saturation/Scatchard analysis was performed with both 20K and 22,000-dalton GH (22K). The majority (approximately 80%) of protein-bound 20K was complexed with a low affinity BP (Ka = approximately 2 x 10(5) M-1), with the remainder complexed with the high affinity2 receptor-related BP. The binding of 20K to the low affinity BP was specific for 20K; it may involve a 20K-specific binding site on the previously described low affinity plasma BP (peak I) or a separate 20K-specific BP. 22K did not interact with this binding site/BP. Analysis of the 20K-BP complex by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and isoelectric focusing suggested, but did not prove, the existence of a separate BP for 20K. We conclude that 20K in plasma binds primarily to a low affinity, 20K-specific binding site (possibly a new, third GH-BP), with only a small fraction bound to the GH receptor-related BP. This binding pattern is markedly different from that of 22K, which is predominantly bound to the receptor-related BP. The existence of a 20K-specific binding site/BP suggests an as yet unrecognized role for this GH variant.

Autoradiography↗
PubMed1993

Analysis of conserved binding proteins for nuclear localization sequences.

Correct targeting of nuclear proteins is mediated by nuclear localization sequences (NLS) which permit specific binding to the nucleus and subsequent translocation across the nuclear envelope via the nuclear pore complex. It is proposed that nuclear import is facilitated by NLS-receptors which reside in the cytoplasm and at the nuclear pore. These NLS-receptors could facilitate an early step of nuclear protein import, i.e. targeting and binding of nuclear proteins at the nuclear pore. We have generated anti-idiotype antibodies against the SV40 T-antigen nuclear localization sequence that allowed us to study NLS-binding proteins in a variety of different organisms. Proteins of similar size are recognized by these antibodies in yeast, Drosophila, rat and human cells. Cytological analysis indicates that the NLS-binding proteins reside in part at nuclear pores. One of the proteins recognized by anti-idiotype antibodies is identical to a previously identified NLS-binding protein. Using isolated yeast nuclei we demonstrate that the anti-idiotype antibodies compete for binding of nuclear proteins in vitro. We show that the yeast mutant npl3, which is defective in nuclear protein localization, has an altered distribution of antigens recognized by these anti-idiotype antibodies, at the semi-permissive temperature. Our results suggest that a set of proteins common to various eukaryotes recognizes nuclear localization sequences.

Amino Acid Sequence↗
PubMed1990

Subcellular distribution of hepatic alanine:glyoxylate aminotransferase in various mammalian species.

The subcellular distribution of alanine:glyoxylate aminotransferase 1 (AGT1) enzyme activity and immunoreactive protein has been determined in the livers of a variety of mammalian species (marmoset, baboon, cat, rabbit, pig, sheep) using the techniques of post-embedding protein A-gold immunoelectron microscopy and isopycnic density gradient centrifugation. In baboon and rabbit livers, AGT1 was exclusively peroxisomal. Morphometric analysis of the distribution of immunoreactive AGT1 protein in cat liver showed that 91-92% was located in the mitochondria with 8-9% in the peroxisomes. In marmoset liver, 59% of AGT1 was found in the mitochondrial matrix and 41% in the peroxisomal matrix. The results from pig and sheep were ambiguous, because of the low levels of expression of AGT1. The implications of these data in terms of the metabolic roles of AGT1 (gluconeogenesis and glyoxylate detoxification) and in terms of the evolutionary acquisition and loss of functional mitochondrial and peroxisomal targeting sequences are discussed.

Alanine Transaminase↗
PubMed2000

Hair cells, hearing and hopping: a field guide to hair cell physiology in the frog.

For more than four decades, hearing in frogs has been an important source of information for those interested in auditory neuroscience, neuroethology and the evolution of hearing. Individual features of the frog auditory system can be found represented in one or many of the other vertebrate classes, but collectively the frog inner ear represents a cornucopia of evolutionary experiments in acoustic signal processing. The mechano-sensitive hair cell, as the focal point of transduction, figures critically in the encoding of acoustic information in the afferent auditory nerve. In this review, we provide a short description of how auditory signals are encoded by the specialized anatomy and physiology of the frog inner ear and examine the role of hair cell physiology and its influence on the encoding of sound in the frog auditory nerve. We hope to demonstrate that acoustic signal processing in frogs may offer insights into the evolution and biology of hearing not only in amphibians but also in reptiles, birds and mammals, including man.

Adaptation, Physiological↗
PubMed1993

Evolution of repeated sequences in non-coding regions of the genome.

Repeated sequences are found ubiquitously in the eukaryotic genome. Population genetic studies on the evolution of such repeated sequences are reviewed while paying special attention to those sequences found in the non-coding regions of the genome. Specifically, the evolution of dispersed repeated sequences by the transposition as well as the evolution of short tandemly repeated sequences due to either replication slippage or unequal sister chromatid exchange are considered. The approach of combining both model and data analyses which has been successfully employed in the development of the neutral theory is also considered to be useful in better understanding the evolution and biological meaning of these sequences.

Animals↗
PubMed1985

Effects of acidification on the mobility of metals and metalloids: an overview.

The exchange rates for metals and metalloids between sediments, soils, water and aquatic biota are discussed in terms of normal and acidified ecosystems. Where it is possible, the pathways for a number of toxic elements are presented with special emphasis on the impact of acidification on changing chemical speciation, and on the potential toxicity of such acid-generated chemical species. Concerns for the impact of acidification on the stability of ecosystems, the safety of drinking water, bioaccumulation in fish and in plants are addressed.

Acids↗