1,530 research outputs found
High-dose etoposide formulations do not saturate intestinal P-glycoprotein:Development, stability, and pharmacokinetics in Sprague-Dawley rats
Percutaneous endoscopic gastrojejunostomy for a patient with an intractable small bowel injury after repeat surgeries: a case report
<p>Abstract</p> <p>Introduction</p> <p>The management of intestinal injury can be challenging, because of the intractable nature of the condition. Surgical treatment for patients with severe adhesions sometimes results in further intestinal injury. We report a conservative management strategy using percutaneous endoscopic gastrojejunostomy for an intractable small bowel surgical injury after repeated surgeries.</p> <p>Case presentation</p> <p>A 78-year-old Japanese woman had undergone several abdominal surgeries including urinary cystectomy for bladder cancer. After this operation, she developed peritonitis as a result of a small bowel perforation thought to be due to an injury sustained during the operation, with signs consistent with systemic inflammatory response syndrome: body temperature 38.5°C, heart rate 92 beats/minute, respiratory rate 23 breaths/minute, white blood cell count 11.7 × 10<sup>9</sup>/L (normal range 4-11 × 10<sup>9</sup>/μL). Two further surgical interventions failed to control the leak, and our patient's clinical condition and nutritional status continued to deteriorate. We then performed percutaneous endoscopic gastrojejunostomy, and continuous suction was applied as an alternative to a third surgical intervention. With this endoscopic intervention, the intestinal leak gradually closed and oral feeding became possible.</p> <p>Conclusion</p> <p>We suggest that the technique of percutaneous endoscopic gastrojejunostomy combined with a somatostatin analog is a feasible alternative to surgical treatment for small bowel leakage, and is less invasive than a nasojejunal tube.</p
A Suction Blister Protocol to Study Human T-cell Recall Responses In Vivo
Cutaneous antigen-recall models allow for studies of human memory responses in vivo. When combined with skin suction blister (SB) induction,
this model offers accessibility to rare populations of antigen-specific T-cells representative of the cellular memory response as well as the
cytokine microenvironment in situ.
This report describes the practical procedure of a cutaneous recall, an SB induction, and a harvest of antigen-specific T-cells. To exemplify
the method, the tuberculin skin test is used for antigenic recall in individuals who, prior to this study, underwent a Bacillus Calmette-Guérin
vaccination against an infection with Mycobacterium tuberculosis. Finally, examples of multiplex and flow cytometric analyses of SB specimens
are provided, illustrating high fractions of antigen-specific polyfunctional CD4+ T-cells available by this sampling method compared with cells
isolated from the blood.
The method described here is safe and minimally invasive, provides a unique opportunity to study both innate and adaptive immune responses
in vivo, and may be beneficial to a broad community of researchers working with cell-mediated immunity and human memory responses, in the
context of vaccine development
Plant responses to photoperiod
Photoperiod controls many developmental responses in animals, plants and even fungi. The response to photoperiod has evolved because daylength is a reliable indicator
of the time of year, enabling developmental events to be scheduled to coincide with particular environmental conditions. Much progress has been made towards
understanding the molecular mechanisms involved in the response to photoperiod in plants. These mechanisms include the detection of the light signal in the leaves,
the entrainment of circadian rhythms, and the production of a mobile signal which is transmitted throughout the plant. Flowering, tuberization and bud set are just a few of the many different responses in plants that are under photoperiodic control. Comparison of what is known of the molecular mechanisms controlling these responses shows that, whilst common components exist, significant differences in the regulatory mechanisms have evolved between these responses
Discovery of cellular regulation by protein degradation
What follows is a story of some of the lab’s adventures mentioned above, including the inventions of new biochemical and genetic methods. This account stems, in part, from previous descriptions of the early history of the Ub field (31,32). Another antecedent is an interview I gave to Dr. Istvan Hargittai, a distinguished Hungarian chemist. It describes my life and science, including the early years in Moscow, the 1977 escape from the former Soviet Union, the essentially accidental hiring of me by MIT, and the work that ensued (33). The narrative below borrows from these sources, and mentions our more recent contributions as well
Entrepreneurial sons, patriarchy and the Colonels' experiment in Thessaly, rural Greece
Existing studies within the field of institutional entrepreneurship explore how entrepreneurs influence change in economic institutions. This paper turns the attention of scholarly inquiry on the antecedents of deinstitutionalization and more specifically, the influence of entrepreneurship in shaping social institutions such as patriarchy. The paper draws from the findings of ethnographic work in two Greek lowland village communities during the military Dictatorship (1967–1974). Paradoxically this era associated with the spread of mechanization, cheap credit, revaluation of labour and clear means-ends relations, signalled entrepreneurial sons’ individuated dissent and activism who were now able to question the Patriarch’s authority, recognize opportunities and act as unintentional agents of deinstitutionalization. A ‘different’ model of institutional change is presented here, where politics intersects with entrepreneurs, in changing social institutions. This model discusses the external drivers of institutional atrophy and how handling dissensus (and its varieties over historical time) is instrumental in enabling institutional entrepreneurship
Evolutionary relationships among barley and <i>Arabidopsis</i> core circadian clock and clock-associated genes
The circadian clock regulates a multitude of plant developmental and metabolic processes. In crop species, it contributes significantly to plant performance and productivity and to the adaptation and geographical range over which crops can be grown. To understand the clock in barley and how it relates to the components in the Arabidopsis thaliana clock, we have performed a systematic analysis of core circadian clock and clock-associated genes in barley, Arabidopsis and another eight species including tomato, potato, a range of monocotyledonous species and the moss, Physcomitrella patens. We have identified orthologues and paralogues of Arabidopsis genes which are conserved in all species, monocot/dicot differences, species-specific differences and variation in gene copy number (e.g. gene duplications among the various species). We propose that the common ancestor of barley and Arabidopsis had two-thirds of the key clock components identified in Arabidopsis prior to the separation of the monocot/dicot groups. After this separation, multiple independent gene duplication events took place in both monocot and dicot ancestors. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00239-015-9665-0) contains supplementary material, which is available to authorized users
Structure of HsdS Subunit from Thermoanaerobacter tengcongensis Sheds Lights on Mechanism of Dynamic Opening and Closing of Type I Methyltransferase
Type I DNA methyltransferases contain one specificity subunit (HsdS) and two modification subunits (HsdM). The electron microscopy model of M.EcoKI-M2S1 methyltransferase shows a reasonable closed state of this clamp-like enzyme, but the structure of the open state is still unclear. The 1.95 Å crystal structure of the specificity subunit from Thermoanaerobacter tengcongensis (TTE-HsdS) shows an unreported open form inter-domain orientation of this subunit. Based on the crystal structure of TTE-HsdS and the closed state model of M.EcoKI-M2S1, we constructed a potential open state model of type I methyltransferase. Mutational studies indicated that two α-helices (aa30-59 and aa466-495) of the TTE-HsdM subunit are important inter-subunit interaction sites in the TTE-M2S1 complex. DNA binding assays also highlighted the importance of the C-terminal region of TTE-HsdM for DNA binding by the TTE-M2S1 complex. On the basis of structural analysis, biochemical experiments and previous studies, we propose a dynamic opening and closing mechanism for type I methyltransferase
Conodonts in Ordovician biostratigraphy
The long time interval after Pander's (1856) original conodont study can in terms of Ordovician conodont biostratigraphical research be subdivided into three periods, namely the Pioneer Period (1856-1955), the Transition Period (1955-1971) and the Modern Period (1971-Recent). During the pre-1920s, the few published conodont investigations were restricted to Europe and North America and were not concerned about the potential use of conodonts as guide fossils. Although primarily of taxonomic nature, the pioneer studies by Branson & Mehl, Stauffer and Furnish during the 1930s represent the beginning of the use of conodonts in Ordovician biostratigraphy. However, no formal zones were introduced until Lindstr\uf6m (1955) proposed four conodont zones in the Lower Ordovician of Sweden, which marks the end of the Pioneer Period. Because Lindstr\uf6m's zone classification was not followed by similar work outside Baltoscandia, the time interval up to the late 1960s can be regarded as a Transition Period. A milestone symposium volume, entitled 'Symposium on Conodont Biostratigraphy' and published in 1971, summarized much new information on Ordovician conodont biostratigraphy and is taken as the beginning of the Modern Period of Ordovician conodont biostratigraphy. In this volume, the Baltoscandic Ordovician was subdivided into named conodont zones, whereas the North American Ordovician succession was classified into a series of lettered or numbered faunas. Although most of the latter did not receive zone names until 1984, this classification has been used widely in North America. The Middle and Upper Ordovician Baltoscandic zone classification, which was largely based on evolutionary species changes in lineages and hence includes phylozones, has subsequently undergone only minor changes and has been used slightly modified also in some other regions, such as New Zealand, China and eastern North America. The great importance of conodonts in Ordovician biostratigraphy is shown by the fact that conodonts are used for the definition of two of the seven global stages, and seven of the 20 stage slices, now recognized within this system
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