High spatial-density, cladding-pumped 6-mode 7-core fiber amplifier for C-band operation.

We present a C-band 6-mode 7-core fiber amplifier in an all-fiberized cladding-pumped configuration for space division multiplexed transmission supporting a record 42 spatial channels. With optimized fiber components (e.g. passively cooled pump laser diode, pump coupler, pump stripper), high power multimode pump light is coupled to the active fiber without any noticeable thermal degradation and an average gain of 18 dB and noise figure of 5.4 dB are obtained with an average differential modal gain of 3.4 dB.

Fishes in a changing world: learning from the past to promote sustainability of fish populations.

Populations of fishes provide valuable services for billions of people, but face diverse and interacting threats that jeopardize their sustainability. Human population growth and intensifying resource use for food, water, energy and goods are compromising fish populations through a variety of mechanisms, including overfishing, habitat degradation and declines in water quality. The important challenges raised by these issues have been recognized and have led to considerable advances over past decades in managing and mitigating threats to fishes worldwide. In this review, we identify the major threats faced by fish populations alongside recent advances that are helping to address these issues. There are very significant efforts worldwide directed towards ensuring a sustainable future for the world's fishes and fisheries and those who rely on them. Although considerable challenges remain, by drawing attention to successful mitigation of threats to fish and fisheries we hope to provide the encouragement and direction that will allow these challenges to be overcome in the future.

A study of fluid provision and consumption in elderly patients in a long-stay rehabilitation hospital.

BACKGROUND: Adequate hydration is key to good clinical care and essential for preventing problems in elderly patients such as constipation, pressure sores and confusion. The present study aimed to evaluate fluid provision and consumption in elderly patients against current standards for Scottish hospitals. METHODS: A service evaluation, of fluid provision and consumption over 24 h by elderly orthopaedic rehabilitation patients in a long-stay hospital in Scotland was conducted. Fluids provided and consumed from trolley services, those at meal times and beverages from jugs of water were measured. The average fluid content of a jug, cup and glass on each ward was determined. Each jug of water provided was recorded, as was the acceptance of hot and cold drinks offered. Intake was determined by measuring the leftover water in each jug when these were refreshed and any leftover liquid in patients' cups deducted from that provided. Observations were made with respect to the presentation and encouragement of fluids. RESULTS: Fifty-eight patients (12 males, 46 female, aged ≥65 years) were monitored, of whom 56 were provided with more than the recommended minimum fluid per day [mean (SEM) = 2379 (82) mL]; however, mean intake was lower than recommended [mean (SEM) = 1302 (60) mL; P = 0.002]. Provision of drinks from a trolley service [mean (SEM) = 956 (44) mL] was less than fluid from jugs [mean (SEM) = 1398 (54) mL; P = 0.002]; however, the consumption of drinks from the trolley was greater [77% consumed, mean (SEM) = 770 (46) mL] than from jugs [41% mean (SEM) = 514 (36) mL; P < 0.001]. CONCLUSIONS: Patients consumed significantly more fluid from individual beverages than jugs. Consideration of the method of fluid provision is important with respect to influencing fluid intakes.

Expanded polyglutamine stretches interact with TAFII130, interfering with CREB-dependent transcription.

At least eight inherited neurodegenerative diseases are caused by expanded CAG repeats encoding polyglutamine (polyQ) stretches. Although cytotoxicities of expanded polyQ stretches are implicated, the molecular mechanisms of neurodegeneration remain unclear. We found that expanded polyQ stretches preferentially bind to TAFII130, a coactivator involved in cAMP-responsive element binding protein (CREB)-dependent transcriptional activation, and strongly suppress CREB-dependent transcriptional activation. The suppression of CREB-dependent transcription and the cell death induced by polyQ stretches were restored by the co-expression of TAFII130. Our results indicate that interference of transcription by the binding of TAFII130 with expanded polyQ stretches is involved in the pathogenetic mechanisms underlying neurodegeneration.

Influence of different rearing systems on natural immune parameters in broiler turkeys.

The aim of this study was to determine serological values of lysozyme, hemolytic complement levels (alternative pathway), and bactericidal activity of serum in turkeys kept in different rearing systems (industrial, backyard, and experimental). Results showed that the values for serum bactericidal activity and hemolytic complement levels increased with age, and their values were higher in experimental and in industrial turkeys than in turkeys reared in backyard. Lysozyme concentration showed a similar pattern; its value was higher in the industrial and experimental groups than in the backyard group. Data obtained suggest that rearing system can have an influence on the natural immune parameters considered; experimental and industrial groups showed a similar trend, differentiated from that observed in the backyard group. In the backyard group, the values observed may suggest that hybrid turkeys, selected for high production, have difficulty with being reared outside where predators (foxes and weasels) and weather conditions could be responsible for a stress situation.

What constitutes a 'good' recovery outcome in post-acute Guillain-Barré syndrome? Results of a nationwide survey of post-acute GBS sufferers in the United Kingdom.

BACKGROUND: Eighty percent of people with Guillain-Barré Syndrome (GBS) are said to achieve 'good' outcome. 'Good' outcome has been defined as either of the top two scores (0 = Healthy, 1 = minor symptoms or signs, able to run) on a 7-point ordinal scale called the F-score. This assessment of 'good' outcome appears to be an arbitrary benchmark. This study is the first assessment of the differences in outcome between post-acute GBS sufferers reporting these scores. It attempts to compare the physical and emotional differences between respondents reporting '0' and '1' on the F-Score. METHODS: A postal survey was administered to respondents through the UK Guillain-Barré Syndrome Support Group's national database and included items relating to general patient data, general mobility, F-Score, Hospital Anxiety and Depression Scale, SF 36 and Fatigue Severity Scale. RESULTS: One thousand five hundred and thirty-five members were surveyed, and of 884/1535 (58%) questionnaires were returned. Results indicate significant differences between those scoring '0' on the F-Score and those scoring '1' in the post-acute phase in terms of anxiety, depression, physical functioning, fatigue and wheelchair use on discharge. CONCLUSIONS: Significantly poorer outcomes for those scoring '1' on the F-Score suggest that only those scoring '0' should constitute a 'good' outcome in GBS.

Variability of NS1 proteins among H9N2 avian influenza viruses isolated in Israel during 2000-2009.

The main aims of the present study were to characterize NS1 protein from H9N2 avian influenza viruses (AIVs) isolated in Israel and to investigate the possibility to use NS1-based indirect ELISA. To achieve these purposes, the non-structural gene (NS1) of 79 AIVs of the H9N2 subtype isolated in Israel in 2000-2009 was sequenced and genetically analyzed. The phylogenetic analysis demonstrated that four distinct introductions of H9N2 occurred in Israel during this period. Analysis of the inferred amino acid sequences of the NS1 proteins showed high, about 10%, differences between viruses of the 3rd and 4th introductions. Antibodies against NS1 protein in immune sera were tested by means of indirect ELISA using recombinant NS1 as antigen. Immune sera were obtained from experimentally H9N2-infected chicken after infection on 4, 7, 10, 14, and 21 days. All sera from chickens experimentally infected with 3rd- or 4th-introduction AIV contained anti-NS1 antibodies that were detected by enzyme-linked immunosorbent assay (NS1-ELISA) even though the recombinant NS1 used as antigen for NS1-ELISA differed significantly in its amino acid sequences from the NS1 protein of AIV that caused infection in experimental birds. These findings indicate that the sites of the NS1 protein by which viruses belonging to 3rd and 4th introduction are out of antigenic epitope positions were responsible for the results of NS1-based iELISA.

Avian influenza virus H9N2 survival at different temperatures and pHs.

The H9N2 avian influenza virus (AIV) subtype has become endemic in Israel since its introduction in 2000. The disease has been economically damaging to the commercial poultry industry, in part because of the synergistic pathology of coinfection with other viral and/or bacterial pathogens. Avian influenza virus viability in the environment depends on the cumulative effects of chemical and physical factors, such as humidity, temperature, pH, salinity, and organic compounds, as well as differences in the virus itself. We sought to analyze the viability of AIV H9N2 strains at three temperatures (37, 20, and 4 C) and at 2 pHs (5.0 and 7.0). Our findings indicated that at 37 C AIV H9N2 isolate 1525 (subgroup IV) survived for a period of time 18 times shorter at 20 C, and 70 times shorter period at 4 C, as measured by a decrease in titer. In addition, the virus was sensitive to a lower pH (pH 5.0) with no detectable virus after 1 wk incubation at 20 C as compared to virus at pH 7.0, which was viable for at least 3 wk at that temperature. The temperature sensitivity of the virus corresponds to the occurrence of H9N2 outbreaks during the winter, and lower pH can greatly affect the viability of the virus.

The histone fold is a key structural motif of transcription factor TFIID.

Transcription factor TFIID is a multiprotein complex composed of the TATA binding protein and its associated factors, and is required for accurate and regulated initiation of transcription by RNA polymerase II. The subunit composition of this factor is highly conserved from yeast to mammals. X-ray crystallography and biochemical experiments have shown that the histone fold motif mediates many of the subunit interactions within this complex. These results, together with electron microscopy and yeast genetics, provide insights into the overall organization of this complex.

Unraveling the puzzle of human anellovirus infections by comparison with avian infections with the chicken anemia virus.

Current clinical studies on human annelloviruses infections are directed towards finding an associated disease. In this review we have emphasized the many similarities between human anellovirus and avian circoviruses and the cell and tissue types infected by these pathogens. We have done this in order to explore whether knowledge acquired from natural and experimental avian infections could reflect and be extrapolated to the less well-characterized human annellovirus infections. The knowledge gained from the avian system may provide suggestions for decoding the enigmatic human anellovirus infections, and finding the specific disease or diseases caused by these human anellovirus infections. Each additional parallelism between chicken anemia virus (CAV) and Torque teno virus (TTV) further strengthens this premise. As we have seen information from human infections can also be used to better understand avian infections as well. Increased attention must be focused on the "hidden" or unrecognized, seemingly asymptomatic effects of circovirus and anellovirus infections. Understanding the facilitating effect of these infections on disease progression caused by other pathogens may help to explain differences in outcome of complicated poultry and human diseases. The final course of a pathogenic infection is determined by variations in the state of health of the host before, during and after contact with a pathogen, in addition to the phenotype of the pathogen and host. The health burden of circoviridae and anellovirus infections may be underestimated, due to lack of awareness of the need to search past the predominant clinical effect of identified pathogens and look for modulation of cellular-based immunity caused by co-infecting circoviruses, and by analogy, human anneloviruses.

The contribution of feathers in the spread of chicken anemia virus.

Chicken anemia virus (CAV) spreads vertically and horizontally, however, the process is mostly still obscure. To further clarify the horizontal CAV spread, we examined the contribution of feathers. We demonstrated that CAV could be amplified from DNA purified from feather shafts of experimentally infected chicks, and the process efficacy was evaluated by comparing the amplification of DNA purified from feather shafts and lymphoid organs of CAV-experimentally infected chicks. DNA from feathers was found as an efficient source for CAV detection. Further, to substantiate whether CAV reaches the feather shafts passively via the blood, or intrinsically, causing histopathological changes, the feather follicle tissues were examined for CAV-induced lesions. Specific histological changes were found, however, immunohistochemistry failed to detect viral proteins. To determine whether the feather shafts are a source of infective virus, they were homogenized and used to infect 1-day-old chicks via the mucosal entries (eyes, nose and oropharynx). That infection mode simulates the natural route of horizontal infection in commercial poultry houses. We demonstrated the CAV-infection by serology, virology and pathology, showing that feather shafts carry infectious CAV either on their surface or within their feather pulp, and concluded that feathers contribute to the horizontal CAV dissemination.

Duplex ultrasound evaluation for dialysis access selection and maintenance: a practical guide.

Detailed case directed history and examination is the mainstay of dialysis access modality selection, ie site and type of access, as well as for maintenance of dialysis access for longevity. As a logical step following history and physical examination, duplex ultrasound evaluation (DUE) is the most cost effective and non-invasive screening tool for evaluation for access placement and for assessment of an established access. Pre-operative vascular mapping allows selection of the optimal dialysis access modality and site. In established accesses, duplex ultrasound testing will diagnose the majority of vascular access complications and direct proper surgical or interventional radiology management. This review outlines a practical decision-making algorithm using DUE for choosing and managing the dialysis access.

Understanding the dialysis access steal syndrome. A review of the etiologies, diagnosis, prevention and treatment strategies.

Distal hypoperfusion ischemic syndrome (DHIS), commonly referred to as hand ischemia or 'steal' after dialysis access placement, occurs in 5-10% of cases when the brachial artery is used, or 10 times that of wrist arteriovenous fistulas (AVFs) using the radial artery. It is typically seen in elderly women with diabetes, and may carry severe morbidity including tissue or limb loss if not recognized and treated. Three distinct etiologies include (1) blood flow restriction to the hand from arterial occlusive disease either proximal or distal to the AV access anastomosis, (2) excess blood flow through the AV fistula conduit (true steal), and (3) lack of vascular (arterial) adaptation or collateral flow reserve (ie atherosclerosis) to the increased flow demand from the AV conduit. These three causes of steal may occur alone or in concert. The diagnosis of steal is based on an accurate history and physical examination and confirmed with tests including an arteriogram, duplex Doppler ultrasound (DDU) evaluation with finger pressures and waveform analysis. Treatment of steal includes observation of developing symptoms in mild cases. Balloon angioplasty is the appropriate intervention for an arterial stenosis. At least three distinct surgical corrective procedures exist to counteract the pathophysiology of steal. The ultimate treatment strategy depends on severity of symptoms, the extent of patient co-morbidity, and the local dialysis access technical team support and skills available.

Human TAF(II)55 interacts with the vitamin D(3) and thyroid hormone receptors and with derivatives of the retinoid X receptor that have altered transactivation properties.

We have identified novel interactions between the human (h)TATA-binding protein-associated factor TAF(II)55 and the ligand-binding domains (LBDs) of the nuclear receptors for vitamin D(3) (VDR) and thyroid hormone (TRalpha). Following expression in Cos cells, hTAF(II)55 interacts with the VDR and TRalpha LBDs in a ligand-independent manner whereas no interactions with the retinoid X receptors (RXRs) or with other receptors were observed. Deletion mapping indicates that hTAF(II)55 interacts with a 40-amino-acid region spanning alpha-helices H3 to H5 of the VDR and TRalpha LBDs but not with the equivalent highly related region of RXRgamma. TAF(II)55 also interacts with chimeric receptors in which the H3-to-H5 region of RXRgamma has been replaced with that of the VDR or TRalpha. Furthermore, replacement of two single amino acids of the RXRgamma LBD with their VDR counterparts allows the RXRgamma LBD to interact with hTAF(II)55 while the corresponding double substitution allows a much stronger interaction. In transfection experiments, the single mutated RXRgamma LBDs activate transcription to fivefold higher levels than wild-type RXRgamma while the double mutation activates transcription to a level comparable to that observed with the VDR. There is therefore a correlation between the ability of the modified RXRs to interact with hTAF(II)55 and transactivation. These results strongly suggest that the TAF(II)55 interactions with the modified RXR LBDs modulate transcriptional activation.

A cell-specific factor represses stimulation of transcription in vitro by transcriptional enhancer factor 1.

Transcription in HeLa cell extracts in vitro was stimulated 8- to 10-fold by a recombinant chimera, GAL-TEF-1, consisting of the DNA-binding domain of GAL4 and the activation function of the HeLa cell activator TEF-1. In contrast, only a 2- to 3-fold stimulation was obtained with GAL-TEF-1 in extracts from BJA-B lymphoid cells. Stimulation by GAL-TEF-1 in BJA-B extracts was dramatically increased by the addition of immunopurified HeLa cell TFIID, suggesting that BJA-B TFIID lacks or contains lower quantities of a TATA-binding-protein-associated factor(s) required for the activity of the TEF-1 activation function. However, chromatography, immunopurification, and transcriptional reconstitution experiments indicated that BJA-B extracts did not lack the previously identified TATA-binding-protein-associated factors required for TEF-1 activity but rather contained a negatively acting factor(s) which inhibited transactivation by GAL-TEF-1. These results indicate that the relative lack of activity of the TEF-1 activation function in vitro in BJA-B cell extracts does not result from the absence of positively acting factors from the presence of a cell-specific negatively acting factor(s).

Transcriptional activation by simian virus 40 large T antigen: interactions with multiple components of the transcription complex.

Simian virus 40 (SV40) large T antigen is a potent transcriptional activator of both viral and cellular promoters. Within the SV40 late promoter, a specific upstream element necessary for T-antigen transcriptional activation is the binding site for transcription-enhancing factor 1 (TEF-1). The promoter structure necessary for T-antigen-mediated transcriptional activation appears to be simple. For example, a promoter consisting of upstream TEF-1 binding sites (or other factor-binding sites) and a downstream TATA or initiator element is efficiently activated. It has been demonstrated that transcriptional activation by T antigen does not require direct binding to the DNA; thus, the most direct effect that T antigen could have on these simple promoters would be through protein-protein interactions with either upstream-bound transcription factors, the basal transcription complex, or both. To determine whether such interactions occur, full-length T antigen or segments of it was fused to the glutathione-binding site (GST fusions) or to the Gal4 DNA-binding domain (amino acids 1 to 147) (Gal4 fusions). With the GST fusions, it was found that TEF-1 and the TATA-binding protein (TBP) bound different regions of T antigen. A GST fusion containing amino acids 5 to 172 (region T1) efficiently bound TBP. TEF-1 bound neither region T1 nor a region between amino acids 168 and 373 (region T2); however, it bound efficiently to the combined region (T5) containing amino acids 5 to 383.(ABSTRACT TRUNCATED AT 250 WORDS)

The human TFIID components TAF(II)135 and TAF(II)20 and the yeast SAGA components ADA1 and TAF(II)68 heterodimerize to form histone-like pairs.

It has been previously proposed that the transcription complexes TFIID and SAGA comprise a histone octamer-like substructure formed from a heterotetramer of H4-like human hTAF(II)80 (or its Drosophila melanogaster dTAF(II)60 and yeast [Saccharomyces cerevisiae] yTAF(II)60 homologues) and H3-like hTAF(II)31 (dTAF(II)40 and yTAF(II)17) along with two homodimers of H2B-like hTAF(II)20 (dTAF(II)30alpha and yTAF(II)61/68). However, it has not been formally shown that hTAF(II)20 heterodimerizes via its histone fold. By two-hybrid analysis with yeast and biochemical characterization of complexes formed by coexpression in Escherichia coli, we showed that hTAF(II)20 does not homodimerize but heterodimerizes with hTAF(II)135. Heterodimerization requires the alpha2 and alpha3 helices of the hTAF(II)20 histone fold and is abolished by mutations in the hydrophobic face of the hTAF(II)20 alpha2 helix. Interaction with hTAF(II)20 requires a domain of hTAF(II)135 which shows sequence homology to H2A. This domain also shows homology to the yeast SAGA component ADA1, and we show that yADA1 heterodimerizes with the histone fold region of yTAF(II)61/68, the yeast hTAF(II)20 homologue. These results are indicative of a histone fold type of interaction between hTAF(II)20-hTAF(II)135 and yTAF(II)68-yADA1, which therefore constitute novel histone-like pairs in the TFIID and SAGA complexes.

Histone folds mediate selective heterodimerization of yeast TAF(II)25 with TFIID components yTAF(II)47 and yTAF(II)65 and with SAGA component ySPT7.

We show that the yeast TFIID (yTFIID) component yTAF(II)47 contains a histone fold domain (HFD) with homology to that previously described for hTAF(II)135. Complementation in vivo indicates that the yTAF(II)47 HFD is necessary and sufficient for vegetative growth. Mutation of highly conserved residues in the alpha1 helix of the yTAF(II)47 HFD results in a temperature-sensitive phenotype which can be suppressed by overexpression of yTAF(II)25, as well as by yTAF(II)40, yTAF(II)19, and yTAF(II)60. In yeast two-hybrid and bacterial coexpression assays, the yTAF(II)47 HFD selectively heterodimerizes with yTAF(II)25, which we show contains an HFD with homology to the hTAF(II)28 family We additionally demonstrate that yTAF(II)65 contains a functional HFD which also selectively heterodimerizes with yTAF(II)25. These results reveal the existence of two novel histone-like pairs in yTFIID. The physical and genetic interactions described here show that the histone-like yTAF(II)s are organized in at least two substructures within TFIID rather than in a single octamer-like structure as previously suggested. Furthermore, our results indicate that ySPT7 has an HFD homologous to that of yTAF(II)47 which selectively heterodimerizes with yTAF(II)25, defining a novel histone-like pair in the SAGA complex.

Chromatin-dependent cooperativity between constitutive and inducible activation domains in CREB.

The cyclic AMP (cAMP)-responsive factor CREB induces target gene expression via constitutive (Q2) and inducible (KID, for kinase-inducible domain) activation domains that function synergistically in response to cellular signals. KID stimulates transcription via a phospho (Ser133)-dependent interaction with the coactivator paralogs CREB binding protein and p300, whereas Q2 recruits the TFIID complex via a direct association with hTAF(II)130. Here we investigate the mechanism underlying cooperativity between the Q2 domain and KID in CREB by in vitro transcription assay with naked DNA and chromatin templates containing the cAMP-responsive somatostatin promoter. The Q2 domain was highly active on a naked DNA template, and Ser133 phosphorylation had no additional effect on transcriptional initiation in crude extracts. Q2 activity was repressed on a chromatin template, however, and this repression was relieved by the phospho (Ser133) KID-dependent recruitment of p300 histone acetyltransferase activity to the promoter. In chromatin immunoprecipitation assays of NIH 3T3 cells, cAMP-dependent recruitment of p300 to the somatostatin promoter stimulated acetylation of histone H4. Correspondingly, overexpression of hTAFII130 potentiated CREB activity in cells exposed to cAMP, but had no effect on reporter gene expression in unstimulated cells. We propose that cooperativity between the KID and Q2 domains proceeds via a chromatin-dependent mechanism in which recruitment of p300 facilitates subsequent interaction of CREB with TFIID.

Synergistic transcriptional activation by TATA-binding protein and hTAFII28 requires specific amino acids of the hTAFII28 histone fold.

Coexpression of the human TATA-binding protein (TBP)-associated factor 28 (hTAFII28) with the altered-specificity mutant TBP spm3 synergistically enhances transcriptional activation by the activation function 2 of the nuclear receptors (NRs) for estrogen and vitamin D3 from a reporter plasmid containing a TGTA element in mammalian cells. This synergy is abolished by mutation of specific amino acids in the alpha2-helix of the histone fold in the conserved C-terminal region of hTAFII28. Critical amino acids are found on both the exposed hydrophilic face of this helix and the hydrophobic interface with TAFII18. This alpha-helix of hTAFII28 therefore mediates multiple interactions required for coactivator activity. We further show that mutation of specific residues in the H1' alpha-helix of TBP either reduces or increases interactions with hTAFII28. The mutations which reduce interactions with hTAFII28 do not affect functional synergy, whereas the TBP mutation which increases interaction with hTAFII28 is defective in its ability to synergistically enhance activation by NRs. However, this TBP mutant supports activation by other activators and is thus specifically defective for its ability to synergize with hTAFII28.