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.

PHYSICAL PROPERTIES OF THE ALLANTOIC AND AMNIOTIC FLUIDS OF THE CHICK : I. SPECIFIC CONDUCTANCE

1. The specific conductance of the allantoic and amniotic fluids of the developing chick has been determined over the period of incubation between the 7th and 19th days. 2. Changes in this property have been related to changes in the chemical composition of these two fluids. 3. These conductance values are of importance in that they show the relation between ionized and un-ionized materials present in the two fluids.

PHYSICAL PROPERTIES OF THE ALLANTOIC AND AMNIOTIC FLUIDS OF THE CHICK : II. HYDROGEN ION CONCENTRATION

1. The hydrogen ion concentration of the allantoic and amniotic fluids of the developing chick has been determined over the period of incubation between the 7th and 19th days using the glass electrode technique. 2. Changes in this property have been related to changes in the chemical composition of these two fluids. 3. The results of this investigation have been compared with those obtained by other workers. Excellent confirmation has been afforded the work of Yamada, whereas the work of Aggazzotti, which has long been accepted, is shown to be in error.

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.

The ultrastructural response of human Leydig cells to exogenous estrogens

The effect of long term treatment with estrogens alone or along with medroxyprogesterone acetate on the Leydig cell ultrastructure was studied in testes from males undergoing surgery for sexual reassignment. The testes were fixed for electron microscopy by a perfusion method to insure uniform preservation. The morphological features were not the same in all the treated testes. Therefore, the cells found in the intertubular region were classified into three groups: (A) Leydig cells very similar to controls; (B) Absence of typical Leydig cells, but with cells having increased microfilaments, abundant smooth endoplasmic reticulum and some lipid droplets; (C) Absence of any cell type possessing abundant smooth endoplasmic reticulum, but having varying amounts of microfilaments and pigmentation. It is suggested that some of the cell types found in the intertubular region are dedifferentiated Leydig cells. This study indicates that the human testis from transsexuals of reproductive age is an appropriate model to study the indirect and direct effects of estrogens on the ultrastructure of cell types found in the human testes.

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.

The BioRap Biodiversity Assessment and Planning Study for Papua New Guinea

Papua New Guinea (PNG) has an incredible variety of land and marine ecosystems, including many components of biodiversity that are unique in the world. PNG's land mass constitutes less than one percent of the world's land area, yet estimates suggest that the country has more than 5% of the world's biodiversity. PNG has been recognized therefore as an important region for biodiversity conservation (see Alcorn 1993; Beehler 1993 and references within). Recently, Conservation International (CI) has recognized PNG as one of the small number of critical tropical forest areas for conservation efforts. That priority reflects not just PNG's unique biodiversity but also the fact that sustainable use of PNG's natural resources has become an important issue, particularly relating to its large mineral deposits, oil and natural gas reserves, agricultural potential, and forestry production potential. CI's perspective highlights important principles of conservation priority. PNG, like the other tropical wilderness areas on its priority list, is regarded as an opportunity for effective conservation at relatively low cost, given that these wilderness regions are still largely intact and have low human population density. In our view, realizing such opportunities requires good planning. Biodiversity conservation in PNG can imply low realized opportunity costs or quite high realized opportunity costs, depending on whether biodiversity planning is used to find a balance among society's competing needs through tradeoffs. PNG is a region worthy of urgent conservation planning attention because potential high net benefits for society may be needlessly foreclosed through inefficient planning that does not address conflicts among various needs of society. The risk of losing those potential net benefits is a strong argument for conservation investment in PNG.

Some future prospects for systematic biodiversity planning in Papua New Guinea - and for biodiversity planning in general

We describe three challenges for biodiversity planning, which arise from a study in Papua New Guinea, but apply equally to biodiversity planning in general. These are 1) the best use of available data for providing biodiversity surrogate information, 2) the integration of representativeness and persistence goals into the area prioritization process, and 3) implications for the implementation of a conservation plan over time. Each of these problems is linked to the effective use of complementarity. Further, we find that a probabilistic framework for calculating persistence-based complementarity values over time can contribute to resolving each challenge. Probabilities allow for the exploration of a range of possible complementarity values over different planning scenarios, and provide a way to evalua!e biodiversity surrogates. The integration of representativeness and persistence goals, via estimated probabilities of persistence, facilitates the crediting of partial protection provided by sympathetic management. For the selection of priority areas and land use allocation, partial protection may be a "given" or implied by an allocated land use. Such an integration also allows the incorporation of vulnerability/threat information at the level of attributes or areas, incorporating persistence values that may depend on reserve design. As an example of the use of persistence probabilities, we derive an alternative proposed priority area set for PNG. This is based on 1) a goal of 0.99 probability of persistence of all biodiversity surrogate attributes used in the study, 2) an assumption of a 0.10 probability of persistence in the absence of any form of formal protection, and 3) a 0.90 probability of persistence for surrogate attributes in proposed priority areas, assuming formal protection is afforded to them. The calculus of persistence also leads to a proposed system of environmental levies based on biodiversity complementarity values. The assigned levy for an area may change to reflect its changing complementarity value in light of changes to protection status of other areas. We also propose a number of complementarity-based options for a carbon credits framework. These address required principles of additionality and collateral benefits from biodiversity protection. A related biodiversity credits scheme, also based on complementarity, encourages investments in those areas that make greatest ongoing contributions to regional biodiversity representation and persistence. All these new methods point to a new "systematic conservation planning" that is not focused only on selecting sets of areas but utilizes complementarity values and changes in probabilities of persistence for a range of decision making processes. The cornerstone of biodiversity planning, complementarity, no longer reflects only relative amounts of biodiversity but also relative probabilities of persistence.

A biodiversity conservation plan for Papua New Guinea based on biodiversity trade-offs analysis

A rapid biodiversity assessment ("BioRap") project identified candidate areas for biodiversity protection in Papua New Guinea (PNG) and provides an ongoing evaluation framework for balancing biodiversity conservation and other land use needs. Achieving a biodiversity protection target with minimum opportunity cost was an important outcome given that biodiversity values overlap with forestry production values, and high forgone forestry opportunities would mean significant losses to land owners and the government. Allocation of 16.8% of PNG's land area to some form of biodiversity protection was required, in order to achieve the level of biodiversity representation/persistence that would have been possible using only 10% of the land area if there were no constraints on land allocation and no land use history. This result minimizes potential conflict with forestry production opportunities while also taking account of land use history, human population density and previous conservation assessments. The analysis provides more than a Single set of proposed priority areas. It is a framework for progressively moving towards a country-wide conservation goal, while at the same time providing opportunities to alter the priority area set in light of new knowledge, changes in land use, and/or changes in economic and social conditions.

Practical application of biodiversity surrogates and percentage targets for conservation in Papua New Guinea

A conservation planning study in Papua New Guinea (PNG) addresses the role of biodiversity surrogates and biodiversity targets, in the context of the trade-offs required for planning given real-world costs and constraints. In a trade-ofts framework, surrogates must be judged in terms of their success in predicting general biodiversity complementarity values ? the amount of additional biodiversity an area can contribute to a protected set. Wrong predictions of low complementarity (and consequent allocation of non-protective land uses) may be more worrisome than wrong predictions of high complementarity (and consequent allocation of protection, perhaps unnecessarily forgoing other land uses benefiting society). Trade-ofts and targets work well when predictions of complementarity are based on surrogate information that is expressed as a continuum of variation. The PNG study used hierarchical variation for environmental domains and vegetation types, and a nominated target then dictated the level within those hierarchies that was used. Internationally-promoted targets provide a potential basis for comparative evaluation of biodiversity protection levels among countries or regions. However, conventional application of percentage targets, in focusing on proportions of total area or on proportions of habitat types, does not serve the goal of biodiversity protection or sustainability well because targets can be miss-used to restrict the amount of biodiversity protected. At the same time, recent complaints about percentage targets are equally misguided in claiming, based on species-area curves, that 10% targets imply 50% extinctions. We apply a new approach to percentage targets in PNG, in which the maximum diversity that could be protected by an unconstrained 10% of the total area of the country becomes the working biodiversity target. Reaching that same biodiversity target may then require more than 10% of the area, because of constraints (e.g., existing reserves) and costs. In the baseline analysis for PNG, we found that hierarchical variation at the level of 564 vegetation types, combined with the 608 environmental domains, could be protected in an unconstrained 10% of the country. This process of determining a biodiversity target also revealed some "must-have" areas for any future conservation plan. Sur.h must-have areas were also identified for a 15%-based target. The satisfaction of the 10%-based target in practice required 16.8% of PNG (Faith et al. 2001a). This low-cost proposed protected set corresponded to greater net benefits relative to our application of two conventional targets approaches.

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.

Sequence and structural determinants of the interaction between the 5'-noncoding region of picornavirus RNA and rhinovirus protease 3C

It has previously been established that human rhinovirus 14 protease 3C binds specifically to the 5'-noncoding region of the viral RNA. A series of mutants of protease 3C and deletion or point mutants of the 5'-noncoding region of the viral RNA were analyzed to elucidate the sites of interaction between the protease and the RNA. Amino acids in protease 3C essential for RNA binding were found to be discontinuous in the amino acid sequence, and mutations which destroyed RNA binding did not affect the catalytic (proteolytic) activity of protease 3C. Based on the three-dimensional structure of rhinovirus 14 protease 3C, the RNA binding region is located in an extended area distinct from the catalytic triad. A single stem-loop structure of 27 nucleotides (stem-loop d) in the 5'-noncoding region was necessary and sufficient to bind protease 3C. Mutagenesis of either the base-paired stem or unpaired loop or bulge regions of stem-loop d suggested that the base-paired stem, but not the loop or bulge, carries important determinants of protease 3C binding. This conclusion is strengthened by the observation that rhinovirus 14 protease 3C bound specifically to the 5'-noncoding region of poliovirus RNA, and only the base-paired stem of stem-loop d is conserved between poliovirus and rhinovirus RNAs.

The human papillomavirus type 16 E2 transcription factor binds with low cooperativity to two flanking sites and represses the E6 promoter through displacement of Sp1 and TFIID

The E6 promoters of all genital human papillomaviruses have a characteristic alignment of transcription factor binding sites. Activation of the basic transcription complex at the TATA box depends upon a sequence-aberrant Sp1 site. Repression of E6 promoters is achieved by two binding sites for the viral E2 protein positioned between the Sp1 site and the TATA box. We have purified the human papillomavirus type 16 E2 protein after expression in Escherichia coli and studied its binding and repression properties with oligonucleotides representing the homologous promoter sequences. A Kd value of 3 x 10(-10) M indicated binding properties expected for a native protein. We found low cooperativity in the binding of two E2 dimers to flanking sites, both when these sites were separated by 3 nucleotides, as in the natural promoter, and when they were further apart. E2 protein, bound close to the distal Sp1 site, displaced the Sp1 factor even when the aberrant sequence was replaced by a typical Sp1 core recognition site. The high affinity of E2 protein for its binding site even led to Sp1 displacement at concentrations of E2 protein nearly 2 orders of magnitude lower than those of Sp1. Functional analyses of mutated E6 promoter sequences showed repression by this distal E2 binding site in the complete absence of binding to the proximal E2 binding site. From our findings and observations published by others, we conclude that each of the E2 binding sites in the E6 promoter of genital human papillomaviruses plays a separate role by displacing the transcription factors Sp1 and TFIID.

Efficient and rapid affinity purification of proteins using recombinant fusion proteases

In the affinity purification of recombinant fusion proteins, the rate-limiting step is usually the efficient proteolytic cleavage and removal of the affinity tail and the protease from the purified recombinant protein. We have developed a rapid, convenient and efficient method of affinity purification which can overcome this limitation. In one example of the method, the protease 3C from a picornavirus (3Cpro), which cleaves specific sequences containing a minimum of 6-7 amino acids, has been expressed as a fusion with glutathione S-transferase. The resultant recombinant 'fusion protease' cleaves fusion proteins bearing (from the amino-terminus) the same affinity tail as the fusion protease, a 3Cpro cleavage recognition site, and the recombinant protein of interest. The recombinant protein is purified in a single chromatographic step which removes both the affinity tail and the fusion protease. The advantages over existing methods include much improved specificity of proteolytic cleavage, complete removal of the protease and the affinity tail in one step, and the option of adding any desired amount of fusion protease to ensure efficient cleavage. The potential flexibility of the method is shown by the use of various affinity tails and alternative fusion proteases.

Human rhinovirus-14 protease 3C (3Cpro) binds specifically to the 5'-noncoding region of the viral RNA. Evidence that 3Cpro has different domains for the RNA binding and proteolytic activities

Protease 3C (3Cpro) encoded by human rhinovirus type 14 was purified from recombinant Escherichia coli and shown to bind specifically to the 5'-terminal 126 nucleotides of the viral RNA (126 RNA) in addition to efficiently cleaving a synthetic peptide in trans. The binding of 3Cpro to the viral RNA may be required for the initiation of plus strand viral RNA synthesis, suggesting a second non-proteolytic function for 3Cpro. Single amino acid substitutions were generated in 3Cpro at residues that are highly conserved among picornaviruses or that lie within the putative catalytic triad. Conservative changes at Asp-85 (D85E and D85N) destroyed the ability of 3Cpro to bind specifically to the 126 RNA, whereas the D85N mutation resulted in almost wild-type levels of proteolytic activity. Conversely, substitutions at His-40, Glu-71, or Cys-146 (H40D, E71A, or C146S) gave proteolytically inactive mutants that bound to the 126 RNA. These results suggest that the highly conserved Asp-85 is essential for specific binding to the 126 RNA, but is unlikely to function in proteolysis as the acidic member of the catalytic triad. Moreover, 3Cpro appears to have different domains for the RNA binding and proteolytic activities.

Characterisation of yeast phosphoglycerate kinase modified by mutagenesis at residue 21

Site-directed mutagenesis has been used to produce mutant forms of yeast phosphoglycerate kinase in which the conserved active-site residue, Arg21, has been replaced by a methionine or a lysine. Kinetic results obtained using these mutant enzymes show that their Km for both 3-phospho-D-glycerate and ATP are significantly different from those recorded for the wild-type enzyme. The Vmax for the lysine mutant is reduced by a factor of two from that of the wild-type enzyme whereas the Vmax for the methionine mutant is reduced more than sevenfold. A very clean electron-density-difference map shows little, if any, evidence of a structural change associated with the C-terminal domain, although resonances in the NMR spectra associated with the ATP-binding site (C-terminal domain) are also affected by the mutation as one might expect from the kinetic results. The NMR data show that binding at both the 3-phospho-D-glycerate and the non-productive ATP-binding site (associated with the N-terminal domain) are affected in the mutant in a way which is different to that associated with the wild-type enzyme. These results, taken together with the X-ray and kinetic data, indicate that the non-productive ATP-binding site and the activating anion-binding site are both associated with the basic patch region of yeast phosphoglycerate kinase.

The Levels of Emotional Awareness Scale: a cognitive-developmental measure of emotion

The Levels of Emotional Awareness Scale (LEAS) is based on a new cognitive-developmental model of emotional experience. The scale poses evocative interpersonal situations and elicits descriptions of the emotional responses of self and others which are scored using specific structural criteria. Forty undergraduates (20 of each sex) were tested. Interrater reliability and intratest homogeneity of the LEAS were strong. The LEAS was significantly correlated with two measures of maturity: the Washington University Sentence Completion Test (SCT) of Ego Development, and the Parental Descriptions Scale-a cognitive-developmental measure of object representation. In addition, the LEAS correlated positively with openness to experience and emotional range but not with measures of specific emotions, repression or the number of words used in the LEAS responses. These findings suggest that it is the level of emotion, not the specific quality of emotion, that is tapped by the LEAS.

Site-directed mutagenesis of histidine 62 in the 'basic patch' region of yeast phosphoglycerate kinase

Site-directed mutagenesis has been used to produce a mutant form of yeast phosphoglycerate kinase (PGK) in which the 'basic patch' residue His 62 has been replaced by a glutamine residue. Using 1H-NMR spectroscopy, it was found that 3-phosphoglycerate (3-PG) binding to the mutant protein induces the same conformational effects as for wild-type PGK, although the affinity was reduced by 2- to 3-fold. Kinetic studies show both Km for 3-PG and Vmax to be increased by approximately 2-fold relative to the wild-type enzyme. These data are consistent with the suggestion that His 62 assists in the binding of the substrate to the enzyme.

A simple, automated functional assay for protein C

Protein C is an important anticoagulant in circulating blood. The balance between the procoagulant and anticoagulant pathways determines whether a patient is at risk for thrombosis or hemorrhage, and low levels of protein C may result in thrombotic disease. It is important for clinical coagulation laboratories to measure protein C. For this purpose, a simple functional assay is needed. This article describes an automated assay for functional protein C with activation by copperhead venom. The authors have automated this assay for a centrifugal analyzer (COBAS Bio) and have proved the specificity of the assay by comparing values obtained amidolytically with those obtained with a radioimmunoassay for protein C.

NMR analysis of site-specific mutants of yeast phosphoglycerate kinase. An investigation of the triose-binding site

Site-specific mutants of yeast phosphoglycerate kinase have been produced in order to investigate the roles of the 'basic-patch' residues, arginine 168 and histidine 170. The fully-conserved residue, arginine 168, has been replaced with a lysine (R168K) and a methionine (R168M) residue, while the non-conserved histidine 170 has been replaced with an aspartate (H170D). Comparison of the 500-MHz 1H-NMR spectra of the mutant proteins with that of wild-type phosphoglycerate kinase shows that the overall fold of the mutants remains essentially unaltered from that of the native enzyme. Results of NOE experiments indicate that there are only very minor changes in structure in the vicinity of the mutations. These mutations have also led to firm sequence-specific resonance assignments to histidines 62, 167 and 170. NMR studies of 3-phosphoglycerate binding show that decreasing the positive charge in the sequence 168-170 reduces the binding of this substrate (by about 15-fold and 4-fold for mutants R168M and H170D respectively). Mutant R168K binds 3-phosphoglycerate with an affinity about twofold less than that of the native enzyme. Significantly, the activity of mutant H170D, measured at saturating substrate concentrations, is unchanged from that of the wild-type enzyme. This indicates that this residue is not of major importance in the binding or reaction of 3-phosphoglycerate. The observation is in agreement with results obtained for the wild-type enzyme, which indicate that 3-phosphoglycerate interacts most strongly with histidine 62 and least strongly with histidine 170, as would be predicted from the X-ray crystal structure. Substitution of positively charged arginine 168 with neutral methionine (or positively charged lysine) does not cause a detectable change in the pKa values of the neighbouring histidine groups, in as much as they remain below 3. The results reported here indicate that the observed reduction in catalytic efficiency relates less to direct electrostatic effects than to the mutants' inability to undergo 3-phosphoglycerate-induced conformational changes.

Site-directed mutagenesis of yeast phosphoglycerate kinase. The 'basic-patch' residue arginine 168

There is evidence, some of it of questionable authenticity, which suggests that phosphoglycerate kinase takes up a more compact form following the binding of substrates. Using this evidence it has been assumed that a conformational rearrangement is required for phosphoryl transfer to occur and that this is brought about by moving the enzyme's two domains towards each other. In order to test this hypothesis we have modified, by site-directed mutagenesis, an arginine residue thought to be involved in stabilising the transition-state intermediate. Although some 1.3 nm away from the site of phosphoryl transfer, as seen in the crystallographically determined structure, the substitution of arginine 168 by lysine (R168K) more than halves the specific activity of the enzyme. Substituting the arginine with a methionine (R168M) reduces activity further, but not completely, thus proving that the charge associated with this residue is not essential for catalytic activity. Both mutations raise the Michaelis constants (Km) for ATP and glycerate 3-phosphate. The largest change is observed with the triose substrate and the methionine mutant, suggesting that the primary function of arginine 168 is to influence the environment of this substrate. The effect on activity of adding sulphate to R168K and R168M mutant enzyme has also been investigated. The sulphate activation effect at low substrate concentrations is reduced for the methionine substitution but almost abolished for the lysine substitution. The most reasonable explanation of all these findings is that, in the wild-type enzyme, the guanidinium group of arginine 168 forms a hydrogen bond with one of the triose substrate's C1 oxygens. This steric arrangement would not be possible in the 'open form' of this enzyme as observed in the crystal structure.

The fate of trace metals during the metamorphosis of chironomids (diptera, chironomidae)

The fate of the trace metals zinc, cadmium and copper during the metamorphosis of chironomids was studied under field and experimental conditions. Field observations demonstrated a significant decrease in the trace metal body burden of larvae and imagines of Stictochironomus histrio Fabricius. No such difference were noted between successive developmental stages of Chironomus anthracinus Zett. The exuviae of both species contained small amounts of trace metals. Experiments, in which larvae of S. histrio and C. riparius Meigen were individually exposed, showed that larvae of both species accumulated substantial amounts of zinc and cadmium. For these metals, a transfer to pupae and imagines occurred. However, pupae had a lower body burden than larvae, and imagines a lower body burden than the pupae. Copper was also accumulated in the larvae, but it was excreted almost completely before the pupal stage. Elimination pathways of the trace metals during metamorphosis and the ecotoxicological consequences of trace metal transfer are discussed.

Ethanol-induced acute gastric injury in mast cell-deficient and congenic normal mice. Evidence that mast cells can augment the area of damage

The authors used stereomicroscopy and planimetry to measure the area of glandular stomach mucosa acutely injured by oral ethanol in mast cell-deficient and congenic normal (+/+) mice, and examined the damaged areas in 1-mu sections. Ethanol caused degranulation and/or disruption of gastric mucosal mast cells, and, at certain concentrations of ethanol, mast cell-deficient WBB6F1-W/Wv or WCB6F1-Sl/Sld mice developed significantly less (43-90% less) acute gastric injury than either congenic +/+ mice or WBB6F1-W/Wv mice whose mast cells were restored by bone marrow transplantation from WBB6F1-+/+ mice. Nevertheless, ethanol produced detectable, and in some cases substantial, gastric injury even in the complete absence of mast cells. Thus, ethanol can produce some damage to the gastric mucosa independently of mast cells. But these data suggest that under certain circumstances mast cells can augment the area of acute gastric injury induced by ethanol.

Synthesis and properties of oligonucleotides containing 2'-deoxynebularine and 2'-deoxyxanthosine

The preparation of synthetic oligonucleotides containing 2'-deoxynebularine (dN) and 2'-deoxyxanthosine (dX) is described. The thermal stabilities of duplexes containing dX, dN, and 2'-deoxyinosine (dI) base-paired with the four natural bases have been measured. Xanthine base pairs have stabilities at pH 5.5 that are similar to those of dI-containing duplexes at neutral pH. When xanthine is paired with adenine or cytosine an unusual stabilization of the duplex structure is observed at acid pH. Incorporation of base mispairs opposite template xanthine sites were measured using Drosophila DNA polymerase alpha. The relative nucleoside incorporation rates are in the order: T greater than C much greater than A approximately equal to G. These rates do not correlate with relative thermodynamic stabilities of base mispairs with xanthine obtained from Tm measurements: T greater than G greater than A approximately equal to C. We suggest that DNA polymerase misinsertion rates are greatest when the base mispair can be formed in accordance with Watson-Crick as opposed to other base pairing geometries even though other geometries, e.g. wobble, may result in a more stable final DNA product.

Land Use in Australia's Rangelands

Arguments for or against the re-allocation of land in Australia's rangelands from one use to another are frequently short on data and long on emotion. Although data presented in this paper are not sufficient to resolve these arguments, they do suggest some options for closer examination.Starting from a model for calculating viability prospects for pastoralism in the rangelands, the paper examines the extent of grazing and the pastoral viability prospects for the areas devoted to each of the major land uses. Possibilities for changes in use in each of the states are also described.

Estimating proximate populations for an extensive set of locations in Australia

"The paper reports the use of Australian Resources Information System to calculate two proximate populations (people living within (i) 150 and (ii) 500 km) for the centroids of each of 3,000 half by half degree geodetic grid cells covering Australia. The use of proximate population data is exemplified by computing a map of the eighteen regions collectively containing a maximum fraction of the Australian population." The data used are from the 1981 census.

Effect of amplification on the intelligibility of speech produced with an electrolarynx

The purpose of this study was to look at the effect of orolabial amplification on the intelligibility of speech spoken with a neck model electrolarynx for two distance conditions, three noise conditions, and in relative quiet. A speaker using a neck model electrolarynx read single-answer questions to six listeners. The questions were read with and without amplification at 1.5 and 2.5 m distance, in relative quiet as well as in 66 dB, 72 dB, and 76 dBSPL (A-weighted) prerecorded cafeteria noise. The results of the study showed that speech-to-noise ratios were improved for amplified speech, with improvement in intelligibility for speech spoken in moderate background noise (66 and 72 dBSPL). The effect of the "buzz" of the artificial larynx is reduced, and speakers are better understood in moderate background noise with this amplification system.

Physical, metabolic, and hormonal effects on men of long-term therapy with medroxyprogesterone acetate

Twenty-three men were treated with injectable medroxyprogesterone acetate (MPA) for sex-offending behavior. The physical, hormonal, and metabolic effects were monitored. The patients had significant (P less than 0.001) weight gain and increases (P less than 0.0001) in systolic blood pressure independent of weight gain. MPA therapy decreased testosterone (P less than 0.0001), luteinizing hormone (P less than 0.005), and testicular size (P less than 0.001), but not follicle-stimulating hormone. MPA's suppression of total sperm count was not consistent, but MPA significantly reduced sperm motility (P less than 0.001) and percent normal morphology (P less than 0.005). Statistically insignificant increases in insulin response without changes in glucose tolerance occurred in all patients, but only one patient developed overt diabetes mellitus. Three men developed gallstones, but none had significant changes in liver function. Patients receiving high-dose MPA therapy should be carefully monitored for blood pressure changes, diabetes mellitus, and gallbladder dysfunction.

The relation between technical variation and the mean in the mixed lymphocyte reaction in the rat

Technical variation is a linear function of the incremental mean in the mixed lymphocyte reaction (MLR) and is independent of the immune status of the responders and the gene dose of the stimulators. Logarithmic transformation of the absolute count/control mean makes technical variation independent of the mean. We recommend that this transformation be used before parametric analysis of the data.

The effect of sex steroids on radioimmunoassayable plasma somatomedin C concentrations

While the effect of sex steroids on growth is well known, their effects on somatomedin C, a mediator of growth, are unclear. To investigate the effect of sex steroids on somatomedin C (Sm-C) concentrations, Sm-C was measured in adults receiving pharmacological doses of various sex steroids (estrogens, testosterone, and medroxyprogesterone acetate). Testosterone therapy had no effect on the somatomedin C concentration. Although both estrogen and medroxyprogesterone acetate therapy reduced the plasma testosterone concentration into the normal female range, they had different effects on Sm-C concentrations. Estrogen therapy produced no detectable change in the Sm-C concentration; medroxyprogesterone acetate caused an increase in the plasma somatomedin C concentration (P less than 0.001). Since medroxyprogesterone acetate also does not increase the serum GH concentration, other mechanisms by which medroxyprogesterone acetate stimulates Sm-C production are discussed.

An alternate method for synthesis of double-stranded DNA segments

Recent progress in the chemical synthesis of DNA has now made it possible to rapidly synthesize single-stranded DNAs over 40 bases in length. We have taken advantage of these longer DNAs in assembling and cloning a 132-base pair gene segment coding for amino acids 126 through the stop codon of human leukocyte interferon alpha 2. The method used involves DNA polymerase I-mediated repair synthesis of synthetic oligonucleotide substrates having short stretches of complementary sequence at their 3' termini. In the presence of DNA polymerase I and the four deoxyribonucleoside triphosphates, those primer-templates are converted to full length double-stranded DNAs. The economy in chemical synthesis using this approach is substantial with a greater than 40% reduction in the amount of chemical synthesis required as compared with the conventional approach. We describe in detail this methodology for the biochemical assembly of long gene segments from synthetic oligodeoxyribonucleotides.