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Recent interest in integrated crop-livestock (ICL) systems has prompted numerous investigations to quantify ecosystem service tradeoffs associated with management. However, few investigations have quantified ICL management effects on net global warming potential (GWP), particularly in semiarid regions. Therefore, we determined net GWP for grazed and ungrazed cropland in a long-term ICL study near Mandan, ND USA. Factors evaluated for their contribution to net GWP included carbon dioxide (CO2) emissions associated with production inputs and field operations, methane (CH4) emissions from enteric fermentation by beef cattle, change in soil carbon stocks, and soil-atmosphere CH4 and nitrous oxide (N2O) fluxes. Net GWP was significantly greater for grazed cropland (946 kg CO2equiv. ha-1 yr-1) compared to ungrazed cropland (200 kg CO2equiv. ha-1 yr-1) (P=0.0331). The difference in net GWP between treatments was largely driven by emissions from enteric fermentation (602 kg CO2equiv. ha-1 yr-1). Among other contributing factors, CO2 emissions associated with seed production and field operations were lower under ungrazed cropland (P = 0.0015 and 0.0135, respectively), while soil CH4 uptake was greater under grazed cropland (P = 0.0102). Soil-atmosphere N2O flux from each system negated nearly all the CO2equiv. sink capacity accrued from soil carbon stock change. As both production systems resulted in net greenhouse gas (GHG) emissions to the atmosphere, novel practices that constrain GHG sources and boost GHG sinks under semiarid conditions are recommended. [ABSTRACT FROM AUTHOR]

Brassicaceae oilseed crops can provide rotation benefits to dryland wheat (Triticum aestivum L.) and supply feedstock for biofuel production. However, growers face decisions about what oilseed crop is best suited for an environment. The objective of this study was to determine how varying production environments affect the agronomic performance of modern cultivars of six Brassicaceae crop species and identify ideal genotypes for seven growing environments spanning four ecoregions. A field experiment was replicated in Colorado, Idaho, Iowa, Minnesota, Montana, North Dakota, and Oregon, USA, between 2013 and 2016 to measure seed and oil yields of seed for four cultivars of Brassica napus, two of B. carinata, two of B. juncea, two of Sinapis alba, one of B. rapa, and one of Camelina sativa. Also, δ13C signature of seed was used as an indicator of water limitation. Generally, across all genotypes, seed and oil yields increased with increased growing season precipitation. Modern commercial cultivars of B. napus and B. juncea had the highest seed oil contents and generally produced the greatest oil yields across most environments, although they were not always the highest seed yielders. For instance, B. carinata over six site years in North Dakota and Minnesota yielded greater than B. napus producing as much as 2471 kg ha−1 in Minnesota. Camelina produced competitive seed yields in some of the drier environments and its δ13C signature indicated that it had the greatest drought resistance. However, seed oil content of some of these high yielding genotypes may need improvement before they are viable as biofuel feedstock. [ABSTRACT FROM AUTHOR]

Nucleosome positioning within the promoter and coding regions of the cellobiohydrolase-encoding cbh1 gene of Trichoderma reesei was investigated. T. reesei is a filamentous fungus that is able to degrade dead plant biomass by secreting enzymes such as cellulases, a feature which is exploited in industrial applications. In the presence of different carbon sources, regulation of one of these cellulase-encoding genes, cbh1, is mediated by various transcription factors including CRE1. Deletion or mutation of cre1 caused an increase in cbh1 transcript levels under repressing conditions. CRE1 was shown to bind to several consensus recognition sequences in the cbh1 promoter region in vitro. Under repressing conditions (glucose), the cbh1 promoter and coding regions are occupied by several positioned nucleosomes. Transcription of cbh1 in the presence of the inducer sophorose resulted in a loss of nucleosomes from the coding region and in the re-positioning of the promoter nucleosomes which prevents CRE1 from binding to its recognition sites within the promoter region. Strains expressing a non-functional CRE1 (in strains with mutated CRE1 or cre1-deletion) exhibited a loss of positioned nucleosomes within the cbh1 coding region under repressing conditions only. This indicates that CRE1 is important for correct nucleosome positioning within the cbh1 coding region under repressing conditions. [ABSTRACT FROM AUTHOR]

Bazedoxifene (Conbriza®, Viviant®) is the first third-generation selective estrogen receptor modulator (SERM) and it is approved for the treatment of postmenopausal osteoporosis in the EU and Japan. Bazedoxifene contains an indole-based core binding domain that binds with high affinity to estrogen receptors and exhibits favourable effects on bone and lipid profiles, with no clinically relevant endometrial or breast stimulation. Oral bazedoxifene once daily reduced the incidence of new vertebral fractures in patients with postmenopausal osteoporosis in a large, well designed trial of 3 years' duration; both bazedoxifene and raloxifene were significantly more effective than placebo. Neither bazedoxifene nor raloxifene reduced the incidence of nonvertebral fractures in the overall study population; however, bazedoxifene, but not raloxifene, reduced the rate of nonvertebral fractures in high- risk patients. Moreover, data from patients who continued to receive the drug during a 2-year extension phase of this trial indicate that bazedoxifene continues to provide protection against new vertebral fractures for up to 5 years. Bazedoxifene also increases bone mineral density and reduces the levels of bone turnover markers. Bazedoxifene was generally well tolerated and did not detrimentally affect the reproductive tract or breast tissue in clinical trials, thereby demonstrating a favourable risk-benefit profile. A pharmacoeconomic analysis conducted from an EU perspective predicted bazedoxifene to be cost effective in some EU countries. Therefore, bazedoxifene presents another useful option for the treatment of postmenopausal osteoporosis, especially in those at high risk for osteoporotic fracture. [ABSTRACT FROM AUTHOR]

Mortierella alpina is an oleaginous filamentous fungus whose vegetative mycelium is known to accumulate triglyceride oil containing large amounts of arachidonic acid (ARA 20:4, n − 6). We report that the spores of Mortierella alpina also contain a large proportion of ARA, comprising 50% of total fatty acid. Fatty acid desaturase genes were not expressed in dormant spores but were induced during germination, following a significant drop in the level of ARA (down from 50% of total fatty acid to 12%) prior to germ-tube emergence. We propose that ARA serves as a reserve supply of carbon and energy that is utilised during the early stages of spore germination in Mortierella alpina. [ABSTRACT FROM AUTHOR]

Several reference materials and associated reference values have been recommended for the purposes of calibration and/or validation of differential scanning calorimetry (DSC). However, issues of available sample purity, reference-property value accuracy, and potential undesired reactions between reference materials and the materials used for sample pans have not been considered sufficiently in some of the recommendations of property values for the materials. These limitations attenuate greatly the usefulness of many of these reference material recommendations. Indeed, the state of uncertainty regarding true reference property values can be shown to be a limiting factor in the uncertainty of measurements made with DSC. NIST has certified the temperatures and enthalpies of fusion of two new Standard Reference Materials, SRMs 2234 and 2235, in order to help alleviate some of the difficulty. [ABSTRACT FROM AUTHOR]

Aims/hypothesis. To investigate the effect of treatment with the non-steroidal anti-inflammatory drug Sulindac on the early vascular pathology of diabetic retinopathy in the dog, and it's effect on recognised biochemical indices of hyperglycaemia-related pathophysiology. Methods. Experimental diabetes (streptozotocin/alloxan) was induced in 22 male beagle dogs and 12 of the animals were assigned at random to receive oral Sulindac (10 mg/kg daily). Age- and sex-matched control animals were maintained as non-diabetic controls. After 4 years, several morphological parameters were quantified in the retinal microvasculature of each animal group using an established stereological method. Also, the following diabetes-associated biochemical parameters were analysed: accumulation of advanced glycation end products (AGEs), red blood cell polyol levels and antioxidant status. Results. Diabetes increased red blood cell sorbitol levels when compared to non-diabetic controls (p≤0.05), however, there was no difference in sorbitol levels between the untreated and the treated diabetic animals. No significant differences were found in red blood cell myoinositol levels between the three groups of animals. Pentosidine and other AGEs were increased two- to three-fold in the diabetic animals (p≤0.001) although treatment with Sulindac did not affect their accumulation in diabetic skin collagen or alter diabetes-induced rises in plasma malondialdehyde. Retinal capillary basement membrane volume was significantly increased in the untreated diabetic dogs compared to non-diabetic controls or Sulindac-treated diabetic animals (p≤0.0001). Conclusion/interpretation. This study has confirmed the beneficial effect of a non-steroidal anti-inflammatory drug on the early vascular pathology of diabetic retinopathy. However the treatment benefit was not dependent on inhibition of polyol pathway activity, advanced glycation, or oxidative stress. [ABSTRACT FROM AUTHOR]

We describe the isolation of a gene ( clxA) encoding calnexin from laboratory and industrial strains of Aspergillus niger. Calnexin is a chaperone, which specifically recognises monoglucosylated glycoproteins in the endoplasmic reticulum, and is thus an essential component of the process that assesses the folded state of nascent secreted glycoproteins. Manipulation of chaperones has previously been adopted in attempts to overcome some of the problems associated with the secretion of heterologous proteins from filamentous fungi. The A. niger c lxA gene encodes a 562-residue protein with strong homology to the calnexin of Schizosaccharomyces pombe. The clxA gene product complements a S. pombe cnx1 mutant. Motifs associated with genes controlled via the Unfolded Protein Response (UPR) were identified by sequence homology in the promoter of clxA. Steady-state levels of clxA mRNA were elevated in a strain expressing bovine prochymosin fused to the catalytic domain of glucoamylase. The ORF is punctuated by four introns, and contains two sets of four repeated peptide motifs that are characteristic of the calnexin family, together with a putative membrane-spanning domain. Deletion studies indicate that clxA is not an essential gene in A. niger. [ABSTRACT FROM AUTHOR]

Genes encoding three enzymes with xylanase activity from the filamentous fungus Penicillium funiculosum are described. Two of the encoded xylanases are predicted to be modular in structure with catalytic and substrate-binding domains separated by a serine and threonine-rich linker region; the other had none of these properties and was non-modular. In order to develop P. funiculosum as a host for the secreted production of heterologous proteins, each of the xylanases was assessed for use as a carrier protein in a fusion strategy. We show that one of the modular xylanases (encoded by xynA) was an effective carrier protein but the other (encoded by xynB) and the non-modular xylanase (encoded by xynC) were not effective as secretion carriers. We show that the β-glucuronidase (GUS) protein from Escherichia coli is secreted by P. funiculosum when expressed as an XYNA fusion but that the secreted GUS protein, cleaved in vivo from XYNA, is glycosylated and enzymatically inactive. [ABSTRACT FROM AUTHOR]

Two genes encoding histone H4 (H4.1 and H4.2) from Penicillium funiculosum have been cloned and characterised. Structurally, the histone H4.1 gene is divergently linked to the histone H3 gene and the two genes are separated by approximately 800 bp. The transcription of the histone H4.1 and H4.2 genes in P. funiculosum appears to be distinctively regulated. Histone H4.1 mRNA showed a high steady-state level during the early stages of batch culture that decreased as growth reached the stationary phase. In contrast, the expression of the histone H4.2 gene was lower than that of H4.1 throughout batch growth and increased gradually with time. In order to expand the industrial application of P. funiculosum as a host for the production of heterologous proteins, the promoter of the histone H4.1 gene was successfully used to drive the expression of an intracellular bacterial enzyme, β-glucuronidase, and a secreted homologous enzyme, xylanase C. The constitutive secretion of xylanase C was achieved in the absence of other xylanases by batch fermentation in the presence of glucose. [ABSTRACT FROM AUTHOR]

Purpose: To seek behavioural, reflexive and histochemical evidence of long-lasting changes in nociceptive stimulus transmission induced by exposure to doses of pentobarbital that induce nocifensive hyperreflexia.Methods: Nocifensive hyperreflexia was induced in 12 rats with 30 mg x kg(-1) pentobarbital ip. Reflex latency times for withdrawal of the hind paw from noxious radiant heat were measured with an automated electronic timer. Subjective responses to noxious stimulation (licking or biting of the stimulated hindpaw) and the level of sedation were recorded. Histological sections of lumbar spinal cord were stained for immunoreactivity of the immediate-early-gene (IEG), c-fos, in three rats that received repeated threshold noxious radiant heat stimulation during the period of nocifensive hyperreflexia induced by 30 mg x kg(-1) pentobarbital ip.Results: Reflex withdrawal latency decreased by 32 +/- 8% of control values (P < 0.001 ) following pentobarbital injection and returned to control values 120 min after drug injection. Once fully alert, pentobarbital-treated animals did not show any increase in nociceptive behaviour relative to saline-injected controls (P = 0.41). Sustained noxious stimulation to the hindpaw in halothane-anesthetized animals was associated with an increase in c-fos immunoreactivity in the dorsal horn of the lumbar spinal cord ipsilateral to the stimulation (P < 0.001). Threshold stimulation in the pentobarbital-treated animals was not associated with any increase in c-fos expression.Conclusions: During pentobarbital-induced hyperreflexia, rats did not show any reflexive, behavioural, or histochemical evidence of long-lasting enhancement of nocifensive signal transmission. The results are consistent with previous observations that, in the absence of tissue injury, nocifensive hyperreflexia induced by barbiturates is a short-lived pharmacological effect. [ABSTRACT FROM AUTHOR]

The putative gene encoding acetyl-CoA carboxylase, accA, has been isolated from Aspergillus nidulans. This single-copy gene has an open reading frame (ORF) of 6864 bp and contains two small introns near the 5′-end. A short ORF upstream of the ATG start codon has been identified in this gene by RT-PCR. Based on sequence homology to acetyl-CoA carboxylases from other organisms, putative biotin-, ATP-, HCO3 –- and acetyl-CoA- binding sites have been assigned. Northern data and ACC enzyme-activity measurements from A. nidulans suggested that expression of accA was higher in media containing nitrate than ammonia as a sole nitrogen source. Deletion of accA in A. nidulans was unsuccessful. The failure of A. nidulans to grow in the presence of the ACC-specific inhibitor, soraphen A, supplemented with C16–18 fatty acids suggested that ACC is an essential enzyme. [ABSTRACT FROM AUTHOR]

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Investigates the relationship between deep-sea-sediment chemistry and atmospheric carbon dioxide (CO(2)) concentration. Global ocean circulation-carbon cycle model and the calcite diagenetic model; Balance between the supply rate of calcium carbonate to the ocean and the alteration of carbonate by burial in weathering; Consequences of the degradation of carbon in sediments.

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We sought to determine if hyperglycaemia is responsible for increased retinal vascular endothelial-cell (RVEC) endocytosis in diabetes and to assess the role of nonenzymatic glycosylation in mediation of this novel endothelial-cell pathology. RVECs were propagated in media containing either 5 or 25 mmol/l glucose for up to 10 days after which they were exposed to the protein tracer horseradish peroxidase for 30 min. The level of RVEC endocytosis was quantified in intact cell monolayers by electron microscopic stereology, and in cell lysates by a simple spectrophotometric method. The effect of the nonenzymatic glycosylation inhibitors, aminoguanidine and d-lysine, on high-glucose medium induced changes in RVEC endocytosis was tested by inclusion of these agents in the culture medium. RVECs exposed to 25 mmol/l glucose showed a stepwise increase in endocytosis of horseradish peroxidase culminating in a two- to threefold increase after 10 days. Endocytosis returned to normal levels after a further 10 days in 5 mmol/l glucose medium. The increase in RVEC endocytosis was markedly reduced, but not completely normalised, by aminoguanidine and d-lysine. Exposure of cultured RVECs to 25 mmol/l glucose causes an increase in endocytosis of similar magnitude to that experienced by RVEC in early diabetes, and implicates hyperglycaemia in the latter situation. A significant component of the increase in RVEC endocytosis appears to be mediated by nonenzymatic glycosylation. [ABSTRACT FROM AUTHOR]

The effect of simulated hyperglycaemia on bovine retinal pericytes was studied following culture of these cells for 10 days under normal (5 mmol/l) and elevated (25 mmol/l) glucose conditions in the absence of endothelial cells. Pericytes cultured under high ambient glucose exhibited both a delayed and reduced contractile response following stimulation with endothelin-1. Stimulation with 10mol/l endothelin-1 for 30 s caused significant contraction in cells grown in both 5 mmol/l and 25 mmol/l glucose. The former also contracted significantly with 10mol/l endothelin-1. Further, at all concentrations tested, statistical comparison of the time course of contraction showed a significant difference ( p<0.02) in the reduction of planimetric surface area between the two cell groups. Since neither binding of endothelin-1 nor the number of receptors for this peptide were significantly different ( p>0.1) between bovine retinal pericytes grown for 10 days under normo- or hyperglycaemic conditions, it became apparent that the altered contractility in bovine retinal pericytes following culture in high glucose must be due to post-binding intracellular disturbance(s). Indeed, both basal and 15 s post-stimulation with 10 mol/l endothelin-1, levels of inositol trisphosphate were significantly reduced ( p<0.05 and p<0.02, respectively) in pericytes cultured for 10 days in 25 mmol/l glucose. These results show that endothelialindependent alterations in contractility of pericytes occur when they are grown in conditions which simulate hyperglycaemia. The results also suggest that the observed attenuation in response to endothelin-1 stimulation evident in pericytes grown under simulated hyperglycaemic conditions is not due to alterations in peptide binding. [ABSTRACT FROM AUTHOR]

The fibrous tissue compartments that develop in response to the subcutaneous implantation of bioerodible heat-fused rods of norethindrone and cholesterol (85 and 15%, respectively) were studied by light and electron microscopy at various intervals after implantation to determine whether the biological inflammatory response may play a role in drug absorption. Thirty-five regularly menstruating, sterilized (tubal ligation), healthy females each received four Annuelle rods. The microanatomy of seven of the largest implants (135 mg norethindrone) was studied. A dense fibrous biological compartment was found to surround each rod. By light microscopy no abnormal tissue response was revealed. Scanning and transmission electron microscopy showed that the surfaces of the rods were covered by a cellular matrix of mononuclear cells. The fibrous compartment was composed of a loose cellular bed immediately surrounding the norethindrone rod, a dense fibrous connective tissue envelope containing blood and lymphatic vessels, and an outer fatty connective tissue layer. Transmission electron microscopy confirmed that the cellular tissue immediately surrounding the rods was composed mainly of lipid laden macrophages. Norethindrone levels in tissue capsules at 3 and 10.5 months were 0.05 and 8.4% by weight, respectively. These observations suggest that the local imflammatory response plays a role in the active processing of this delivery system. This picture is qualitatively different from the general view of the fibrous capsule as a simple rate limiting membrane. The effects observed in this study suggest that a more complex, functional biological system develops in response to the subcutaneous introduction of a drug delivery device. [ABSTRACT FROM AUTHOR]

Three DNA fragments, trs1, 2 and 3, were isolated from the Trichoderma reesei genome on the basis of their ability to promote autonomous replication of plasmids in Saccharomyces cerevisiae. Each trs element bound specifically to the isolated T. reesei nuclear matrix in vitro, and two of them bound in vivo, indicating that they are matrix attachment regions (MARs). A similar sequence previously isolated from Aspergillus nidulans ( ans1) was also shown to bind specifically to the T. reesei nuclear matrix in vitro. The T. reesei MARs are AT-rich sequences containing 70%, 86% and 73% A+T over 2.9, 0.8 and 3.7 kb, respectively for trs1, 2 and 3. They exhibited no significant sequence homology, but were shown to contain a number of sequence motifs that occur frequently in many MARs identified in other eukaryotes. However, these motifs occurred as frequently in the trs elements as in randomly generated sequences with the same A+T content. trs1 and 3 were shown to be present as single copies in the T. reesei genome. The presence of the trs elements in transforming plasmids enhanced the frequency of integrative transformation of T. reesei up to five fold over plasmids without a trs. No evidence was obtained to suggest that the trs elements promoted efficient replication of plasmids in T. reseei. A mechanism for the enhancement of transformation frequency by the trs elements is proposed. [ABSTRACT FROM AUTHOR]

The effect of treatment with an aldose reductase inhibitor on the susceptibility of peripheral nerves to compression was studied in rats made diabetic by the injection of streptozotocin (50 mg·kg). The response to nerve compression was determined in untreated diabetic rats after 22 days of diabetes and compared with the response in two similar groups of diabetic rats which had been treated with the aldose reductase inhibitor 'Statil' (ICI 128436; 25 mg·kg· day orally) either from the induction of diabetes or for 7 days prior to nerve compression. Two groups of non-diabetic rats were treated with 'Statil' for either 22 days or 7 days to act as controls. Inhibition of fast axonally transported proteins was induced by local compression of the sciatic nerves 4 h after application of H-leucine to the motor neurone cell bodies in the spinal cord. The inhibition of fast axonal transport was quantified by calculation of a transport block ratio. Compression at 30 mmHg for 3 h induced a significantly greater ( p<0.05) inhibition of axonal transport at the site of compression in nerves of untreated diabetic rats (transport block ratio 0.96±0.24, n=8) than in nerves of control rats treated with the aldose reductase inhibitor for either the shorter time of 7 days (0.71±0.17, n=10) or the longer time of 22 days (0.69±0.08, n=5). In diabetic rats treated with the aldose reductase inhibitor for 22 days the inhibition (0.77±0.12, n=6) was significantly less than that in untreated diabetic rats; treatment for 7 days reduced the transport block ratio to 0.85±0.11 ( n=8), but the effect was not significant. Treatment for 22 days prevented the marked increase in nerve sorbitol found in the diabetic rats but did not prevent a fall in nerve myo-inositol. The results indicate that treatment with an aldose reductase inhibitor for a sufficient period of time can reduce the increased susceptibility of peripheral nerves to compression in streptozotocin-induced diabetes mellitus in the rat by a mechanism which may be related to the prevention of increases in sorbitol in the nerves. [ABSTRACT FROM AUTHOR]

The secreted production of a heterologous enzyme, hen egg-white lysozyme, by Aspergillus niger was studied in shake flasks containing media of different initial viscosities. Raising the viscosity of the medium by addition of polyvinylpyrrolidone (PVP) brought about a transition in the form of growth from aggregated mycelia (pellets) to dispersed mycelia. The specific yield of lysozyme in cultures containing an initial concentration of 5% (w/v) starch was 8 mg lysozyme/g dry weight. Addition of 2% (w/v) PVP to the medium resulted in a specific yield of 14 mg lysozyme/g dry weight. [ABSTRACT FROM AUTHOR]

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Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Anaesthesia / Journal Canadien d'Anesthésie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Current strategies to improve the secretion of heterologous proteins from Aspergillus niger include the manipulation of chaperones and foldases specific to the endoplasmic reticulum (ER). Here we report the isolation of a gene, pdiA, encoding a putative protein disulphide isomerase (PDI) from A. niger using the Saccharomyces cerevisiae PDI gene as a probe. Sequencing of a genomic clone and RT-PCR products predict a 515-aa protein comprising a 20-aa ER-translocation signal sequence and a 495-aa mature protein (Mr = 54.3 kDa). The predicted protein also contains two thiol oxidoreductase active sites with a -CGHC- motif and a carboxy terminal -HDEL ER-retention signal. Three introns were identified within the pdiA gene and Southern- and dot-blot analysis indicates that the gene is present in a single copy. Northern-blot analysis shows a transcript of the predicted size. Sequence homology to a motif associated with protein trafficking and the induction of chaperones has been identified in the pdiA promoter. Transcription of pdiA is induced 3–4-fold after treatment with tunicamycin, an inhibitor of N-linked glycosylation. The kinetics of induction suggest that pdiA expression is not part of the primary stress response. [ABSTRACT FROM AUTHOR]

Washed cell suspensions of Methanobacterium formicicum MF, Methanobacterium bryantii M.o.H.G. and Methanobacterium strain FR-2 but not Methanobacterium bryantii M.o.H., were shown to produce hydrogen and methane from formate. Levels of dissolved gases (H and CH) were continuously and simultaneously monitored within a closed reaction vessel using membrane inlet mass spectrometry. Growth on formate (0-50mM), measured by methane production and increase in absorbance, was observed for both M. formicicum MF and M. bryantii M.o.H.G. but not with Methanobacterium strain FR-2 or M. bryantii M.o.H. [ABSTRACT FROM AUTHOR]

© 1999 Cancer Research Campaign [ABSTRACT FROM AUTHOR]

The inner blood-retinal barrier is highly complex, dependent on a normally functioning retinal vascular endothelium and possibly adjacent perivascular cells. There are undoubtedly many different grades of barrier failure, and in the early stages an inbuilt compensatory mechanism may prevent significant fluid accumulation and delay associated structural and functional changes. In diabetes, early barrier failure may be a function of an increase in the rate of endothelial cell death and turnover, probably exaggerated by the early and widespread loss of the supporting cells and dilatation of the small blood vessels. [ABSTRACT FROM AUTHOR]

Cilia exhibited unidirectional and coordinated movement within microsurgically reversed segments of rabbit ampulla when examined up to 13 months after surgery. The direction of ciliary beating was opposite that of the remainder of the oviduct. [ABSTRACT FROM AUTHOR]

The [402]5/2 bands inTa which are 'identical' to the neighboring even-evenHf groundstate band have been extended to higher angular momentum. These bands in the two nuclei are seen to diverge from each other in the region of the first i neutron alignment. The lower observed crossing frequency for the [402]5/2 bands indicates a lower deformation for these bands compared toHf. Extensions to the h [541]1/2 yrast band are also reported. [ABSTRACT FROM AUTHOR]