Seasonal migration of the starry smooth-hound shark Mustelus asterias as revealed from tag-recapture data of an angler-led tagging programme.

The primary aim of this long-term angler-led tagging programme was to gain information about seasonal changes in distribution of the starry smooth-hound shark Mustelus asterias, along the Dutch coast for management and conservation purposes. Between 2011 and 2014, M. asterias comprised 92·6% (n = 2418) of the total elasmobranch catch (n = 2612) by the licenced group of taggers within the Dutch Delta of which 2244 M. asterias were fin-tagged with plastic rototags. Sex and total length (LT ) composition inside the eastern tidal basin (Oosterschelde) were significantly different, i.e. more females and larger individuals, than outside indicating a pupping ground, which was confirmed by the capture of 30 newborn pups (≤32 cm). The distribution pattern of reported recaptured M. asterias (return-rate 3·6%, n = 80) showed a circannual migration between summering in the southern North Sea and wintering in the English Channel and the Bay of Biscay, and suggests that M. asterias is philopatric. The Dutch angling season for M. asterias runs from approximately mid-May to mid-October when the water temperature is above 13° C. Recaptures of eight mature females, but no males in the Bay of Biscay, indicate partial spatial segregation by sex, where mature females migrate over larger distances than immature females and males. These observations, with the absence of recaptures in other known summering areas (i.e. the Irish Sea and Bristol Channel), suggest that the southern North Sea is used by a separate population. Implications for management and recommendations to improve and expand the study approach are discussed.

Solitary fibrous tumour presenting as a pedunculated lung mass with associated lung atresia: report of a case.

This case report describes a solitary fibrous tumour presenting as a pedunculated mass arising from an almost completely atretic right middle lobe of lung. The intraoperative findings and pathologic diagnostic criteria used are described. To our knowledge, this is the first case report of a solitary fibrous tumour associated with partial lung atresia.

Evaluating the effects of immediate application of negative pressure therapy after decompression from abdominal compartment syndrome in an experimental porcine model.

PURPOSE: The purpose of this large-animal study was to assess the safety and effects of negative pressure therapy (NPT) when used as temporary abdominal closure in the immediate post-decompression period after abdominal compartment syndrome (ACS). METHODS: Using a hemorrhagic shock/resuscitation and mesenteric venous pressure elevation model, ACS was physiologically induced in 12 female Yorkshire swine. At decompression, animals were allocated to either NPT (n = 6) or Bogota bag (n = 6) as temporary abdominal closure and studied for a period of 48 h or until death. Outcomes measured included morbidity and mortality, as well as hemodynamic parameters, ventilator-related measurements, blood gases, coagulation factors, and organ (liver, kidney, lung, and intestinal) edema and histology at the time of death/sacrifice. RESULTS: All animals developed ACS. Early application of NPT was associated with decreases in mesenteric venous and central venous pressure, and significantly increased drainage of peritoneal fluid. In addition, there was no increase in the incidence of mortality, recurrent intra-abdominal hypertension/ACS, or any deleterious effects on markers of organ injury. CONCLUSIONS: Early application of NPT in this porcine ACS model is safe and does not appear to be associated with an increased risk of recurrent intra-abdominal hypertension. The results of this animal study suggest that the application of NPT following decompression from ACS results in greater peritoneal fluid removal and may translate into augmented intestinal edema resolution secondary to more favorable fluid flux profiles.

A murine model for the study of edema induced intestinal contractile dysfunction.

BACKGROUND: We have published extensively regarding the effects of edema on intestinal contractile function. However, we have found the need to expand our model to mice to take advantage of the much larger arsenal of research support, especially in terms of transgenic mouse availability and development. To that end, we have developed and validated a hydrostatic intestinal edema model in mice. METHODS: Male C57 Black 6 mice were subjected to a combination of high volume crystalloid resuscitation and mesenteric venous hypertension in an effort to induce hydrostatic intestinal edema. Wet to dry ratios, myeloperoxidase activity, mucosal injury scoring, STAT-3 nuclear activation, phosphorylated STAT-3 levels, NF-κB nuclear activation, myosin light chain phosphorylation, intestinal contractile activity, and intestinal transit were measured to evaluate the effects of the model. KEY RESULTS: High volume crystalloid resuscitation and mesenteric venous hypertension resulted in the development of significant intestinal edema without an increase in myeloperoxidase activity or mucosal injury. Edema development was associated with increases in STAT-3 and NF-κB nuclear activation as well as phosphorylated STAT-3. There was a decrease in myosin light chain phosphorylation, basal and maximally stimulated intestinal contractile activity, and intestinal transit. CONCLUSION & INFERENCES: Hydrostatic edema in mice results in activation of a signal transduction profile that culminates in intestinal contractile dysfunction. This novel model allows for advanced studies into the pathogenesis of hydrostatic edema induced intestinal contractile dysfunction.

Current trends in cell therapy for pediatric acquired brain injury.

Pediatric traumatic brain injury (TBI) represents a major burden on healthcare worldwide. In the United States, TBI accounts for 435000 Emergency Department visits, 37000 hospital admissions, and approximately 2500 deaths each year. While aggressive early rehabilitation has shown some functional improvement, the acute care of TBI with focus on controlling intracranial pressure while maintaining adequate cerebral perfusion has not shown the ability to reverse neuronal injury on either a cellular or subcellular level. Preliminary investigation into the use of cell therapeutics has shown promise for the treatment of TBI in animal models. While progenitor cells may potentially act via altering the intracerebral milieu (modulation of inflammatory response and trophic factor secretion), the exact mechanism remains controversial. In addition, traditional delivery vehicles (intravenous, intra-arterial, intrathecal injections, and direct implantation) have shown significant barriers to translation coupled with inconsistent results. Therefore, investigation into novel delivery vehicles such as nanofiber scaffolds and hydrogels could enhance transplant cell viability, engraftment, and efficacy. Overall, a large amount of preclinical work remains to clearly define optimal progenitor cell type, dosage, and delivery vehicle. The optimal therapeutic benefit may be seen using a combination of therapies (controlled hypothermia, hypertonic therapy, and/or cellular therapeutics) to attack the complex pathophysiology of TBI at multiple points.

Structural basis for oseltamivir resistance of influenza viruses.

Oseltamivir, one of the two anti-neuraminidase drugs, is currently the most widely used drug against influenza. Resistance to the drug has occurred infrequently among different viruses in response to drug treatment, including A H5N1 viruses, but most notably has emerged among recently circulating A H1N1 viruses and has spread throughout the population in the absence of drug use. Crystal structures of enzyme-drug complexes, together with enzymatic properties, of mutants of H5N1 neuraminidase have provided explanations for high level oseltamivir resistance due to the common H275Y mutation, with retention of zanamivir susceptibility, and intermediate level resistance due to the N295S mutation. Complementation of enhanced NA activity due to a D344N mutation by the H275Y mutation suggests an explanation for the recent emergence and predominance of oseltamivir-resistant influenza A H1N1 viruses.

NF-kappaB1 p105 negatively regulates TPL-2 MEK kinase activity.

Activation of the oncogenic potential of the MEK kinase TPL-2 (Cot) requires deletion of its C terminus. This mutation also weakens the interaction of TPL-2 with NF-kappaB1 p105 in vitro, although it is unclear whether this is important for the activation of TPL-2 oncogenicity. It is demonstrated here that TPL-2 stability in vivo relies on its high-affinity, stoichiometric association with NF-kappaB1 p105. Formation of this complex occurs as a result of two distinct interactions. The TPL-2 C terminus binds to a region encompassing residues 497 to 534 of p105, whereas the TPL-2 kinase domain interacts with the p105 death domain. Binding to the p105 death domain inhibits TPL-2 MEK kinase activity in vitro, and this inhibition is significantly augmented by concomitant interaction of the TPL-2 C terminus with p105. In cotransfected cells, both interactions are required for inhibition of TPL-2 MEK kinase activity and, consequently, the catalytic activity of a C-terminally truncated oncogenic mutant of TPL-2 is not affected by p105. Thus, in addition to its role as a precursor for p50 and cytoplasmic inhibitor of NF-kappaB, p105 is a negative regulator of TPL-2. Insensitivity of C-terminally truncated TPL-2 to this regulatory mechanism is likely to contribute to its ability to transform cells.

The role of trade-offs in biodiversity conservation planning: linking local management, regional planning and global conservation efforts.

Biodiversity conservation planning requires trade-offs, given the realities of limited resources and the competing demands of society. If net benefits for society are important, biodiversity assessment cannot occur without other sectoral factors "on the table". In trade-offs approaches, the biodiversity value of a given area is expressed in terms of the species or other components of biodiversity that it has that are additional to the components protected elsewhere. That "marginal gain" is called the complementarity value of the area. A recent whole-country planning study for Papua New Guinea illustrates the importance of complementarity-based trade-offs in determining priority areas for biodiversity conservation, and for designing economic instruments such as biodiversity levies and offsets. Two international biodiversity programs provide important new opportunities for biodiversity trade-offs taking complementarity into account. Both the Millennium Ecosystem Assessment and the Critical Ecosystems or "hotspots" programs can benefit from an explicit framework that incorporates trade-offs, in which a balance is achieved not only by land-use allocation among areas, but also by the crediting of partial protection of biodiversity provided by sympathetic management within areas. For both international programs, our trade-offs framework can provide a natural linkage between local, regional and global planning levels.

The structural basis of Arfaptin-mediated cross-talk between Rac and Arf signalling pathways.

Small G proteins are GTP-dependent molecular switches that regulate numerous cellular functions. They can be classified into homologous subfamilies that are broadly associated with specific biological processes. Cross-talk between small G-protein families has an important role in signalling, but the mechanism by which it occurs is poorly understood. The coordinated action of Arf and Rho family GTPases is required to regulate many cellular processes including lipid signalling, cell motility and Golgi function. Arfaptin is a ubiquitously expressed protein implicated in mediating cross-talk between Rac (a member of the Rho family) and Arf small GTPases. Here we show that Arfaptin binds specifically to GTP-bound Arf1 and Arf6, but binds to Rac.GTP and Rac.GDP with similar affinities. The X-ray structure of Arfaptin reveals an elongated, crescent-shaped dimer of three-helix coiled-coils. Structures of Arfaptin with Rac bound to either GDP or the slowly hydrolysable analogue GMPPNP show that the switch regions adopt similar conformations in both complexes. Our data highlight fundamental differences between the molecular mechanisms of Rho and Ras family signalling, and suggest a model of Arfaptin-mediated synergy between the Arf and Rho family signalling pathways.

Structure of the TPR domain of p67phox in complex with Rac.GTP.

p67phox is an essential part of the NADPH oxidase, a multiprotein enzyme complex that produces superoxide ions in response to microbial infection. Binding of the small GTPase Rac to p67phox is a key step in the assembly of the active enzyme complex. The structure of Rac.GTP bound to the N-terminal TPR (tetratricopeptide repeat) domain of p67phox reveals a novel mode of Rho family/effector interaction and explains the basis of GTPase specificity. Complex formation is largely mediated by an insertion between two TPR motifs, suggesting an unsuspected versatility of TPR domains in target recognition and in their more general role as scaffolds for the assembly of multiprotein complexes.

Isotachophoretic separations on a microchip. Normal Raman spectroscopy detection.

Isotachophoretic separations of the herbicides paraquat and diquat are performed in a glass microchip etched channel and monitored on-chip by normal Raman spectroscopy. The 40-micron-wide and 75-micron-deep separation channels are chemically etched in a serpentine design to 21-cm total length. A 120-micron-thick glass cover slip is used to seal the channels. Separation field strengths up to 380 V/cm are used. The microchip is directly coupled to a Raman microprobe. No interfacing is required. Raman spectra are generated with a 2-W, 532-nm NdY-VO4 laser and collected at 8-cm-1 resolution with a holographic transmissive spectrograph and a cryogenically cooled CCD. Data acquisition is at 2-5 spectra/s. Raman isotachopherograms of the pesticides at starting concentrations as low as 2.3 x 10(-7) M (60 ppb paraquat/80 ppb diquat) are presented.

Capillary isotachophoresis with fiber-optic Raman spectroscopic detection. Performance and application to ribonucleotides.

A fiber-optic Raman probe fitted with a microscope objective was used to obtain on-line normal Raman spectra of adenosine 5'-monophosphate, cytidine 5'-monophosphate, guanosine 5'-monophosphate and uridine 5'-monophosphate separated by capillary isotachophoresis. With multimode optical fiber, the system interrograted a 40-micron length of capillary. Fiber-optic coupling facilitated use of an unmodified spectrograph and conventional capillary mounting systems. Raman spectra were excited with a 2W 532 nm NdYVO4, laser as the excitation source, with collection of 1 spectrum per second. Even at 2.10(-5) M initial concentration, Raman spectra were obtained at a good signal-to-noise ratio.

Structure at 1.65 A of RhoA and its GTPase-activating protein in complex with a transition-state analogue.

Small G proteins of the Rho family, which includes Rho, Rac and Cdc42Hs, regulate phosphorylation pathways that control a range of biological functions including cytoskeleton formation and cell proliferation. They operate as molecular switches, cycling between the biologically active GTP-bound form and the inactive GDP-bound state. Their rate of hydrolysis of GTP to GDP by virtue of their intrinsic GTPase activity is slow, but can be accelerated by up to 10(5)-fold through interaction with rhoGAP, a GTPase-activating protein that stimulates Rho-family proteins. As such, rhoGAP plays a crucial role in regulating Rho-mediated signalling pathways. Here we report the crystal structure of RhoA and rhoGAP complexed with the transition-state analogue GDP.AlF4- at 1.65 A resolution. There is a rotation of 20 degrees between the Rho and rhoGAP proteins in this complex when compared with the ground-state complex Cdc42Hs.GMPPNP/rhoGAP, in which Cdc42Hs is bound to the non-hydrolysable GTP analogue GMPPNP. Consequently, in the transition state complex but not in the ground state, the rhoGAP domain contributes a residue, Arg85(GAP) directly into the active site of the G protein. We propose that this residue acts to stabilize the transition state of the GTPase reaction. RhoGAP also appears to function by stabilizing several regions of RhoA that are important in signalling the hydrolysis of GTP.

Crystal structure of a small G protein in complex with the GTPase-activating protein rhoGAP.

Small G proteins transduce signals from plasma-membrane receptors to control a wide range of cellular functions. These proteins are clustered into distinct families but all act as molecular switches, active in their GTP-bound form but inactive when GDP-bound. The Rho family of G proteins, which includes Cdc42Hs, activate effectors involved in the regulation of cytoskeleton formation, cell proliferation and the JNK signalling pathway. G proteins generally have a low intrinsic GTPase hydrolytic activity but there are family-specific groups of GTPase-activating proteins (GAPs) that enhance the rate of GTP hydrolysis by up to 10(5) times. We report here the crystal structure of Cdc42Hs, with the non-hydrolysable GTP analogue GMPPNP, in complex with the GAP domain of p50rhoGAP at 2.7A resolution. In the complex Cdc42Hs interacts, mainly through its switch I and II regions, with a shallow pocket on rhoGAP which is lined with conserved residues. Arg 85 of rhoGAP interacts with the P-loop of Cdc42Hs, but from biochemical data and by analogy with the G-protein subunit G(i alpha1), we propose that it adopts a different conformation during the catalytic cycle which enables it to stabilize the transition state of the GTP-hydrolysis reaction.

Specific cleavage of the retinoblastoma protein by an ICE-like protease in apoptosis.

Interleukin 1beta-converting enzyme-like (ICE-like) proteases are important mediators of apoptosis in diverse cell types and organisms. However, the role of these proteases in apoptosis cannot be satisfactorily explained on the basis of the physiological functions of their known substrates. Here we show that the C-terminal 42 amino acid peptide of the retinoblastoma (Rb) protein, an important cell cycle regulator with a known anti-apoptotic function, is specifically cleaved off by an ICE-like protease in tumour necrosis factor (TNF)- and staurosporine-induced apoptosis. Cleavage of Rb induced by TNF was blocked in vivo and in vitro by two specific inhibitors of ICE-like proteases, and in vitro by a point mutation (Asp886 to Ala) within the ICE-like protease cleavage site of Rb, (883)DEAD(886). An antibody raised against the C-terminal 15 amino acid peptide of Rb recognized the full-length but not the cleaved form of Rb. The extent of Rb cleavage correlated directly with TNF-induced apoptosis in all tumour cell lines examined. Cleaved Rb bound cyclin D3 and inhibited the transcriptional activity of E2F-1, but failed to bind to the regulatory protein MDM2, which has been implicated in apoptosis. As Rb suppresses cell death and its C-terminus has important regulatory functions, our results suggest that Rb cleavage is an important event in apoptosis.

Pulmonary disease.

This article has presented the reader with an overview of the pulmonary disorders that develop during the course of HIV disease with special emphasis on the more commonly encountered entities. This information is intended to prepare the clinician to recognize the hallmark characteristics of the various diseases as well as atypical features. Despite the advances in basic understanding of the clinicopathologic consequences of infection with HIV, a cure has not been realized. There has, however, been success in controlling some of the major pulmonary problems that adversely affect both the quality and the length of life for persons with AIDS. For most complications of HIV infection, prognosis ultimately depends not only on treatment of the specific problem, but also controlling the relentless process of progressive immunosuppression. Continued research into treatment or prevention of HIV infection itself is needed, but at present prevention, rapid diagnosis, and treatment of recognized problems remain an intermediary goal.

Hearing conservation in surgery for glomus jugulare tumors.

The most common ground on which surgery for glomus jugulare (GJ) tumors is criticized is the perceived risk of functional incapacity that attends possible cranial nerve (CN) loss. It is aggregate lower CN loss that is most often highlighted as particularly disabling to the quality of postsurgical survival. The documented success of both conservation surgery and operative rehabilitation of phonopharyngeal surgical deficits has, however, neutralized much of this criticism. The issue of hearing conservation (HC) in neurotologic skull base surgery, on the other hand, has not been well documented toward this end. The presence of a GJ neoplasm need not reflexly nor technically forfeit preexisting hearing. HC is, admittedly, a subordinate priority to total tumor removal, successful distal control of the internal carotid artery, and even facial nerve integrity. Yet, in appropriately selected patients, existing operative technology permits hearing preservation, a noteworthy addition to the high-grade functional outcome we have come to reasonably expect of conservation surgery. Hearing salvage further serves to define the concept of neurotologic skull base surgery. Hearing preservation in 122 GJ tumor patients is reviewed. Intuitively, as for acoustic tumor, HC appears tumor size related. Selection criteria for conservation surgery and its operative technique are detailed. Outcome is appropriately scored. The radiation therapy literature on this subject will be assiduously scrutinized for comparison.

On-line Raman spectroscopy of ribonucleotides preconcentrated by capillary isotachophoresis.

Normal Raman spectroscopy is used as an on-line detector for capillary isotachophoresis (ITP) of adenosine 5'-triphosphate, adenosine 5'-diphosphate, and adenosine 5'-monophosphate in phosphate buffers. Preconcentration is from a 1 x 10(-2) M phosphate buffer (pH 7.5) into a leading electrolyte of 0.1 M KCl or Na2SO4, with a terminating electrolyte of 0.1 M 4-morpholinepropane-sulfonic acid. The ribonucleotides are concentrated to above 10(-2) M at the detection window, allowing measurement of Raman spectra with 1 s integration, from starting concentrations of 5 x 10(-6) M or higher.