Assessment of Drought and Zinc Stress Tolerance of Novel Miscanthus Hybrids and Arundo donax Clones Using Physiological, Biochemical, and Morphological Traits

High-yield potential perennial crops, such as Miscanthus spp. and Arundo donax are amongst the most promising sources of sustainable biomass for bioproducts and bioenergy. Although several studies assessed the agronomic performance of these species on diverse marginal lands, research to date on drought and zinc (Zn) resistance is scarce. Thus, the objective of this study was to investigate the drought and Zn stress tolerance of seven novel Miscanthus hybrids and seven Arundo clones originating from different parts of Italy. We subjected both species to severe drought (less than 30%), and Zn stress (400 mg/kg-1 of ZnSO4) separately, after one month of growth. All plants were harvested after 28 days of stress, and the relative drought and Zn stress tolerance were determined by using a set of morpho-physio-biochemical and biomass attributes in relation to stress tolerance indices (STI). Principal component analysis (PCA), hierarchical clustering analysis (HCA) and stress tolerance indices (STI) were performed for each morpho-physio-biochemical and biomass parameters and showed significant relative differences among the seven genotypes of both crops. Heatmaps of these indices showed how the different genotypes clustered into four groups. Considering PCA ranking value, Miscanthus hybrid GRC10 (8.11) and Arundo clone PC1 (11.34) had the highest-ranking value under both stresses indicating these hybrids and clones are the most tolerant to drought and Zn stress. In contrast, hybrid GRC3 (-3.33 lowest ranking value) and clone CT2 (-5.84) were found to be the most sensitive to both drought and Zn stress.

Novel Miscanthus hybrids: Modelling productivity on marginal land in Europe using dynamics of canopy development determined by light interception

New biomass crop hybrids for bioeconomic expansion require yield projections to determine their potential for strategic land use planning in the face of global challenges. Our biomass growth simulation incorporates radiation interception and conversion efficiency. Models often use leaf area to predict interception which is demanding to determine accurately, so instead we use low-cost rapid light interception measurements using a simple laboratory-made line ceptometer and relate the dynamics of canopy closure to thermal time, and to measurements of biomass. We apply the model to project the European biomass potentials of new market-ready hybrids for 2020-2030. Field measurements are easier to collect, the calibration is seasonally dynamic and reduces influence of weather variation between field sites. The model obtained is conservative, being calibrated by crops of varying establishment and varying maturity on less productive (marginal) land. This results in conservative projections of miscanthus hybrids for 2020-2030 based on 10% land use conversion of the least (productive) grassland and arable for farm diversification, which show a European potential of 80.7-89.7 Mt year-1 biomass, with potential for 1.2-1.3 EJ year-1 energy and 36.3-40.3 Mt year-1 carbon capture, with seeded Miscanthus sacchariflorus × sinensis displaying highest yield potential. Simulated biomass projections must be viewed in light of the field measurements on less productive land with high soil water deficits. We are attempting to model the results from an ambitious and novel project combining new hybrids across Europe with agronomy which has not been perfected on less productive sites. Nevertheless, at the time of energy sourcing issues, seed-propagated miscanthus hybrids for the upscaled provision of bioenergy offer an alternative source of renewable energy. If European countries provide incentives for growers to invest, seeded hybrids can improve product availability and biomass yields over the current commercial miscanthus variety.

Uptake and speciation of Zn and Pb by Miscanthus grown in contaminated soils

The uptake by and distribution of Zn and Pb within a novel seed-based Miscanthus hybrid grown in contaminated soil was assessed. Results from juvenile plants in a pot-trial was compared with data for mature biomass of the same species harvested during a field-trial. Both Zn and Pb uptake by juvenile plants were observed to increase in proportion to the soil concentrations. Both Zn and Pb accumulation differed between leaf and stem structures, and both were different in the mature biomass compared with juvenile plants. Analysis of X-Ray Absorption Fine Structures (XAFS) revealed different Zn speciation in stems and leaves, and differences in Zn speciation with plant maturity. Sulfur ligands consistent with the presence of cysteine rich metallothioneins (MT) and phytochelatin (PC) complexes were the dominant Zn species in juvenile plant leaves, together with octahedral O/N species typified by Zn-malate. Sulfur ligands were also prevalent in stems from juvenile plants, but predominant O/N speciation shifted towards tetrahedral coordination. In contrast, tetrahedral Zn coordination with O/N species predominated in the mature biomass crop. The XAFS spectra for the mature biomass were consistent with Zn being retained within cell walls as pectin and/or phosphate complexes.

MRI for Cushing Disease: A Systematic Review

BACKGROUND

MR imaging is key in the diagnostic work-up of Cushing disease. The sensitivity of MR imaging in Cushing disease is not known nor is the prognostic significance of "MR imaging-negative" disease.

PURPOSE

Our aim was to determine the overall sensitivity and prognostic significance of MR imaging localization of Cushing disease.

DATA SOURCES

We performed a systematic review of the MEDLINE and PubMed databases for cohort studies reporting the sensitivity of MR imaging for the detection of adenomas in Cushing disease.

STUDY SELECTION

This study included 57 studies, comprising 5651 patients.

DATA ANALYSIS

Risk of bias was assessed using the methodological index for non-randomized studies criteria. Meta-analysis of proportions and pooled subgroup analysis were performed.

DATA SYNTHESIS

Overall sensitivity was 73.4% (95% CI, 68.8%-77.7%), and the sensitivity for microadenomas was 70.6% (66.2%-74.6%). There was a trend toward greater sensitivity in more recent studies and with the use of higher-field-strength scanners. Thinner-section acquisitions and gadolinium-enhanced imaging, particularly dynamic sequences, also increased the sensitivity. The use of FLAIR and newer 3D spoiled gradient-echo and FSE sequences, such as spoiled gradient-echo sequences and sampling perfection with application-optimized contrasts by using different flip angle evolutions, may further increase the sensitivity but appear complementary to standard 2D spin-echo sequences. MR imaging detection conferred a 2.63-fold (95% CI, 2.06-3.35-fold) increase in remission for microadenomas compared with MR imaging-negative Cushing disease.

LIMITATIONS

Pooled analysis is limited by heterogeneity among studies. We could not account for variation in image interpretation and tumor characteristics.

CONCLUSIONS

Detection on MR imaging improves the chances of curative resection of adenomas in Cushing disease. The evolution of MR imaging technology has improved the sensitivity for adenoma detection. Given the prognostic importance of MR imaging localization, further effort should be made to improve MR imaging protocols for Cushing disease.

Expanding the Miscanthus market in the UK: Growers in profile and experience, benefits and drawbacks of the bioenergy crop

To achieve net zero greenhouse gas emission by 2050 as set out by the 2019 amendment to the 2008 UK Climate Change Act, a major shift towards renewable energy is needed. This includes the development of new methods along with improving and upscaling existing technologies. One example of new methods in bioenergy is developing new Miscanthus cultivars for electricity generation via thermal power station furnaces. Miscanthus is still relatively new compared with other agriculture practices, so market assessments and improvements are needed to reduce the barriers to entry for prospective growers. This publication provides a profile of UK Miscanthus growers and their businesses, their experiences of benefits and drawbacks of the crop, and what they see as potential barriers to entry for prospective farmers. A survey of current Miscanthus growers in England and Wales was conducted and indicated that most farmers were content with the crop and that its environmental and economic benefits were noted. However, it was evident that with a geographically limited UK market, growers wanted to see a better distribution of biomass processing stations to reduce the ongoing costs of transport. With growing demand for renewables, including bio-energy sources, it was determined important to provide information and support for stable farming operations and to incentivise the adoption of Miscanthus. Such incentives include ongoing development of new cultivars, focussing on traits such as production potential and stressor resilience, and growers indicated preference for an annual planting grant. These developments are predicted to further improve the crop's profit margin, making it a more cost-effective crop for farmers. Sensitively managed Miscanthus also has the potential to contribute to carbon sequestration, soil health, and aspects of farmland biodiversity. Incentivising such management in government land-based environmental schemes would offer additional income streams and help to promote environmental positive crop planting.

Myocilin Mutations in Patients With Normal-Tension Glaucoma

Importance

Mutations in the myocilin (MYOC) gene are the most common molecularly defined cause of primary open-angle glaucoma that typically occurs in patients with high intraocular pressures (IOP). One MYOC mutation, p.Gln368Ter, has been associated with as many as 1.6% of primary open-angle glaucoma cases that had a mean maximum recorded IOP of 30 mm Hg. However, to our knowledge, the role of the p.Gln368Ter mutation in patients with normal-tension glaucoma (NTG) with an IOP of 21 mm Hg or lower has not been investigated.

Objective

To evaluate the role of the p.Gln368Ter MYOC mutation in patients with NTG.

Design, Setting, and Participants

In this case-control study of the prevalence of the p.Gln368Ter mutation in patients with NTG, cohort 1 was composed of 772 patients with NTG and 2152 controls from the United States (Iowa, Minnesota, and New York) and England and cohort 2 was composed of 561 patients with NTG and 2606 controls from the Massachusetts Eye and Ear Infirmary and the NEIGHBORHOOD consortium. Genotyping was conducted using real-time polymerase chain reaction that was confirmed with Sanger sequencing, the imputation of genome-wide association study data, or an analysis of whole-exome sequence data. Data analysis occurred between April 2007 and April 2018.

Main Outcomes and Measures

Comparison of the frequency of the p.Gln368Ter MYOC mutation between NTG cases and controls with the Fisher exact test.

Results

Of 6091 total participants, 3346 (54.9%) were women and 5799 (95.2%) were white. We detected the p.Gln368Ter mutation in 7 of 772 patients with NTG (0.91%) and 7 of 2152 controls (0.33%) in cohort 1 (P = .03). In cohort 2, we detected the p.Gln368Ter mutation in 4 of 561 patients with NTG (0.71%) and 10 of 2606 controls (0.38%; P = .15). When the cohorts were analyzed as a group, the p.Gln368Ter mutation was associated with NTG (odds ratio, 2.3; 95% CI, 0.98-5.3; P = .04).

Conclusions and Relevance

In cohorts 1 and 2, the p.Gln368Ter mutation in MYOC was found in patients with IOPs that were 21 mm Hg or lower (NTG), although at a frequency that is lower than previously detected in patients with higher IOP. These data suggest that the p.Gln368Ter mutation may be associated with glaucoma in patients with normal IOPs as well as in patients with IOPs that are greater than 21 mm Hg.

BaRTv1.0: an improved barley reference transcript dataset to determine accurate changes in the barley transcriptome using RNA-seq

BACKGROUND

The time required to analyse RNA-seq data varies considerably, due to discrete steps for computational assembly, quantification of gene expression and splicing analysis. Recent fast non-alignment tools such as Kallisto and Salmon overcome these problems, but these tools require a high quality, comprehensive reference transcripts dataset (RTD), which are rarely available in plants.

RESULTS

A high-quality, non-redundant barley gene RTD and database (Barley Reference Transcripts - BaRTv1.0) has been generated. BaRTv1.0, was constructed from a range of tissues, cultivars and abiotic treatments and transcripts assembled and aligned to the barley cv. Morex reference genome (Mascher et al. Nature; 544: 427-433, 2017). Full-length cDNAs from the barley variety Haruna nijo (Matsumoto et al. Plant Physiol; 156: 20-28, 2011) determined transcript coverage, and high-resolution RT-PCR validated alternatively spliced (AS) transcripts of 86 genes in five different organs and tissue. These methods were used as benchmarks to select an optimal barley RTD. BaRTv1.0-Quantification of Alternatively Spliced Isoforms (QUASI) was also made to overcome inaccurate quantification due to variation in 5' and 3' UTR ends of transcripts. BaRTv1.0-QUASI was used for accurate transcript quantification of RNA-seq data of five barley organs/tissues. This analysis identified 20,972 significant differentially expressed genes, 2791 differentially alternatively spliced genes and 2768 transcripts with differential transcript usage.

CONCLUSION

A high confidence barley reference transcript dataset consisting of 60,444 genes with 177,240 transcripts has been generated. Compared to current barley transcripts, BaRTv1.0 transcripts are generally longer, have less fragmentation and improved gene models that are well supported by splice junction reads. Precise transcript quantification using BaRTv1.0 allows routine analysis of gene expression and AS.

BaRTv1.0: an improved barley reference transcript dataset to determine accurate changes in the barley transcriptome using RNA-seq

BACKGROUND

The time required to analyse RNA-seq data varies considerably, due to discrete steps for computational assembly, quantification of gene expression and splicing analysis. Recent fast non-alignment tools such as Kallisto and Salmon overcome these problems, but these tools require a high quality, comprehensive reference transcripts dataset (RTD), which are rarely available in plants.

RESULTS

A high-quality, non-redundant barley gene RTD and database (Barley Reference Transcripts - BaRTv1.0) has been generated. BaRTv1.0, was constructed from a range of tissues, cultivars and abiotic treatments and transcripts assembled and aligned to the barley cv. Morex reference genome (Mascher et al. Nature; 544: 427-433, 2017). Full-length cDNAs from the barley variety Haruna nijo (Matsumoto et al. Plant Physiol; 156: 20-28, 2011) determined transcript coverage, and high-resolution RT-PCR validated alternatively spliced (AS) transcripts of 86 genes in five different organs and tissue. These methods were used as benchmarks to select an optimal barley RTD. BaRTv1.0-Quantification of Alternatively Spliced Isoforms (QUASI) was also made to overcome inaccurate quantification due to variation in 5' and 3' UTR ends of transcripts. BaRTv1.0-QUASI was used for accurate transcript quantification of RNA-seq data of five barley organs/tissues. This analysis identified 20,972 significant differentially expressed genes, 2791 differentially alternatively spliced genes and 2768 transcripts with differential transcript usage.

CONCLUSION

A high confidence barley reference transcript dataset consisting of 60,444 genes with 177,240 transcripts has been generated. Compared to current barley transcripts, BaRTv1.0 transcripts are generally longer, have less fragmentation and improved gene models that are well supported by splice junction reads. Precise transcript quantification using BaRTv1.0 allows routine analysis of gene expression and AS.

Harnessing Finger Millet to Combat Calcium Deficiency in Humans: Challenges and Prospects

Humans require more than 20 mineral elements for healthy body function. Calcium (Ca), one of the essential macromineral, is required in relatively large quantities in the diet for maintaining a sound overall health. Young children, pregnant and nursing women in marginalized and poorest regions of the world, are at highest risk of Ca malnutrition. Elderly population is another group of people most commonly affected by Ca deficiency mainly in the form of osteoporosis and osteopenia. Improved dietary intake of Ca may be the most cost-effective way to meet such deficiencies. Finger millet [Eleusine coracana (L.) Gaertn.], a crop with inherently higher Ca content in its grain, is an excellent candidate for understanding genetic mechanisms associated with Ca accumulation in grain crops. Such knowledge will also contribute toward increasing Ca contents in other staple crops consumed on daily basis using plant-breeding (also known as biofortification) methods. However, developing Ca-biofortified finger millet to reach nutritional acceptability faces various challenges. These include identifying and translating the high grain Ca content to an adequately bioavailable form so as to have a positive impact on Ca malnutrition. In this review, we assess some recent advancements and challenges for enrichment of its Ca value and present possible inter-disciplinary prospects for advancing the actual impact of Ca-biofortified finger millet.

Abiotic stress upregulated TaZFP34 represses the expression of type-B response regulator and SHY2 genes and enhances root to shoot ratio in wheat

Q-type C₂H₂ zinc finger proteins (ZFPs) are plant-specific DNA-binding proteins containing a conserved QALGGH motif. This study investigated the function of abiotic stress-inducible and predominantly root-expressed Triticum aestivum ZFPs (TaZFP22, TaZFP34 and TaZFP46) with a focus on TaZFP34. Expression of TaZFP34 in roots was upregulated by high salinity, dehydration, oxidative and cold stresses. Overexpression of TaZFP34 in wheat roots resulted in an increased root-to-shoot ratio, a phenomenon observed during plant adaptation to drying soil. Expression of a number of genes which are potentially involved in modulating root growth was significantly altered in the roots of TaZFP34 overexpressing lines. In particular, the transcript levels of TaRR12B, TaRR12D and TaSHY2 that are homologues of known negative regulators of root growth were significantly reduced. Expression of shoot growth-related genes, such as GA3-ox and expansins, was downregulated in the transgenic shoots. TaZFP34 bound to (C/G)AGT(G/A)-like elements in the promoters of TaZFP34 down-regulated TaRR12D and TaSHY2 and transrepressed the reporter gene expression driven by TaRR12D and TaSHY2 promoters. Expression of the above reporter genes was also repressed by TaZFP46 and TaZFP22. These data suggest that TaZFP34 is a transcriptional repressor and is involved in modulating the root-to-shoot ratio.

Dietary Interventions for Type 2 Diabetes: How Millet Comes to Help

Diabetes has become a highly problematic and increasingly prevalent disease world-wide. It has contributed toward 1.5 million deaths in 2012. Management techniques for diabetes prevention in high-risk as well as in affected individuals, beside medication, are mainly through changes in lifestyle and dietary regulation. Particularly, diet can have a great influence on life quality for those that suffer from, as well as those at risk of, diabetes. As such, considerations on nutritional aspects are required to be made to include in dietary intervention. This review aims to give an overview on the general consensus of current dietary and nutritional recommendation for diabetics. In light of such recommendation, the use of plant breeding, conventional as well as more recently developed molecular marker-based breeding and biofortification, are discussed in designing crops with desired characteristics. While there are various recommendations available, dietary choices are restricted by availability due to geo-, political-, or economical- considerations. This particularly holds true for countries such as India, where 65 million people (up from 50 million in 2010) are currently diabetic and their numbers are rising at an alarming rate. Millets are one of the most abundant crops grown in India as well as in Africa, providing a staple food source for many poorest of the poor communities in these countries. The potentials of millets as a dietary component to combat the increasing prevalence of global diabetes are highlighted in this review.

Optical coherence tomography based microangiography as a non-invasive imaging modality for early detection of choroido-neovascular membrane in choroidal rupture

Introduction

To evaluate and identify early microvascular changes in patient with choroidal rupture using optical coherence tomography (OCT) based microangiography (OMAG).

Case description

One patient (one eye) with confirmed diagnosis of choroidal rupture after sustained ocular blunt trauma underwent OMAG imaging. OMAG was performed by Zeiss spectral domain OCT-angiography prototype using a “6.5 mm × 6.5 mm” field of view around macular region. The resulting images were presented into bilayers: the retinal layer and the choroidal layer.

Discussion and evaluation

Choroidal rupture sites were easily shown on OMAG images with clear evidence of multiple breaks in Bruch’s membrane involving macula and the region superior to nerve. OMAG provided detailed vascular network patterns in the areas of choroidal rupture, showing a concern for choroidal neovascularization (CNV). The OMAG demonstrated cross sectional area to visualize CNV location relative to the other layers of the retina, identifying functional blood vessels through the lesion. The patient’s progress was followed using OMAG.

Conclusion

The images provided by OMAG give detailed microvascular findings about the macula and adjacent retinal region along with the underlying choroidal alternations. In our case, details of the architecture and vascular flow of CNVM in choroidal rupture was delivered by OMAG, which were used to follow the progression of the disease progression. Further studies are needed to assess the role of quantitative and qualitative OCT microangiography in the evaluation and treatment of choroidal rupture.

Optical coherence tomography based microangiography findings in hydroxychloroquine toxicity

Optical coherence tomography based microangiography (OMAG) is a new, non-invasive imaging modality capable of providing three dimentional (3D) retinal and choroidal microvascular maps without a need for exogenous dye. In this study, we evaluated the retinal and choroidal microvascular architecture of the macula in a patient with hydroxychloroquine (HCQ) toxicity using OMAG. Detailed microvascular information of the retina and the underlying choroid showed loss of parafoveal outer retinal vasculature with sparing of the central fovea vasculature.

Plant lignin content altered by soil microbial community

Questions have been raised in various fields of research about the consequences of plants with modified lignin production. As a result of their roles in nutrient cycling and plant diversity, plant-soil interactions should be a major focus of ecological studies on lignin-modified plants. However, most studies have been decomposition studies conducted in a single soil or in sterile soil. Thus, we understand little about plant-soil interactions in living lignin-modified plants. In lignin mutants of three different barley (Hordeum vulgare) cultivars and their corresponding wild-types associated with three different soil microbial communities, we asked: do plant-soil microbiome interactions influence the lignin content of plants?; does a mutation in lignin production alter the outcome of plant-soil microbiome interactions?; does the outcome of plant-soil microbiome interactions depend on host genotype or the presence of a mutation altering lignin production? In roots, the soil community explained 6% of the variation in lignin content, but, in shoots, the soil community explained 21% of the variation in lignin content and was the only factor influencing lignin content. Neither genotype nor mutations in lignin production explained associations with fungi. Lignin content changes in response to a plant's soil microbial community, and may be a defensive response to particular components of the soil community.

Ethylene insensitivity conferred by a mutated Arabidopsis ethylene receptor gene alters nodulation in transgenic Lotus japonicus

BACKGROUND AND AIMS

Transgenics are used to demonstrate a causal relationship between ethylene insensitivity of a seedling legume plant, the level of ethylene receptor gene expression, lateral root growth and Mesorhizobium loti-induced nodule initiation.

METHODS

Lotus japonicus plants expressing the dominant etr1-1 allele of the Arabidopsis thaliana gene encoding a well-characterized mutated ethylene receptor were created by stable Agrobacterium tumefaciens transformation. Single insertion, homozygous lines were characterized for symbiotic properties.

KEY RESULTS

Transgenic plants were ethylene insensitive as judged by the lack of the 'Triple Response', and their continued ability to grow and nodulate in the presence of inhibitory concentrations of ACC (1-aminocyclopropane-1-carboxylic acid; an ethylene precursor). Transgenic plants with high insensitivity to ACC had significantly fewer lateral roots and exhibited increased nodulation while showing no altered nitrate sensitivity or lack of systemic autoregulation. Whereas ACC-insensitive shoot growth and nodulation were observed in transformants, root growth was inhibited similarly to the wild type. Increased nodulation was caused by increased infection and a seven-fold increase in nodules developing between xylem poles. Bacteroid numbers per symbiosome increased about 1.7-fold in ethylene-insensitive plants.

CONCLUSIONS

The study further demonstrates multiple roles for ethylene in nodule initiation by influencing root cell infections and radial positioning, independent of autoregulation and nitrate inhibition of nodulation.

The Q-type C2H2 zinc finger subfamily of transcription factors in Triticum aestivum is predominantly expressed in roots and enriched with members containing an EAR repressor motif and responsive to drought stress

Q-type C2H2 zinc finger proteins (ZFPs) form a subfamily of transcription factors that contain a plant-specific QALGGH amino acid motif. A total of 47 expressed Q-type C2H2 zinc finger genes in bread wheat (Triticum aestivum) (designated TaZFP) were identified from the current databases. Protein sequence analysis for the presence of ERF-associated amphiphilic repressor (EAR) motif sequences from known transcriptional repressors revealed that 26% of the TaZFP subfamily members contain an EAR motif. Quantitative RT-PCR analysis of the mRNA distribution of 44 TaZFP genes in various organs revealed that 30 genes were predominantly expressed in the roots. The majority of the TaZFP genes showed significant changes in their mRNA levels during leaf development and aging. Expression of 37 TaZFP genes in the leaves and roots responded to drought stress at least in one organ with 74% of the drought-responsive TaZFP genes being down-regulated in the drought-stressed roots. In contrast, only 6 out of the 44 TaZFP genes showed expression changes in the leaves with sucrose treatment. Expression of 50% of the drought-responsive TaZFP genes in the leaves (16 genes analysed) did not respond to ABA treatment, indicating that some TaZFP genes are involved in ABA-independent signalling pathways. These results indicate that the Q-type TaZFP subfamily is likely to have an important role in wheat roots and is enriched with members that are potentially involved in regulating cellular activities during changes of the physiological status of plant cells, as it occurs during drought stress or leaf development/aging.

Differential maturation and subcellular localization of severe acute respiratory syndrome coronavirus surface proteins S, M and E

Post-translational modifications and correct subcellular localization of viral structural proteins are prerequisites for assembly and budding of enveloped viruses. Coronaviruses, like the severe acute respiratory syndrome-associated virus (SARS-CoV), bud from the endoplasmic reticulum-Golgi intermediate compartment. In this study, the subcellular distribution and maturation of SARS-CoV surface proteins S, M and E were analysed by using C-terminally tagged proteins. As early as 30 min post-entry into the endoplasmic reticulum, high-mannosylated S assembles into trimers prior to acquisition of complex N-glycans in the Golgi. Like S, M acquires high-mannose N-glycans that are subsequently modified into complex N-glycans in the Golgi. The N-glycosylation profile and the absence of O-glycosylation on M protein relate SARS-CoV to the previously described group 1 and 3 coronaviruses. Immunofluorescence analysis shows that S is detected in several compartments along the secretory pathway from the endoplasmic reticulum to the plasma membrane while M predominantly localizes in the Golgi, where it accumulates, and in trafficking vesicles. The E protein is not glycosylated. Pulse-chase labelling and confocal microscopy in the presence of protein translation inhibitor cycloheximide revealed that the E protein has a short half-life of 30 min. E protein is found in bright perinuclear patches colocalizing with endoplasmic reticulum markers. In conclusion, SARS-CoV surface proteins S, M and E show differential subcellular localizations when expressed alone suggesting that additional cellular or viral factors might be required for coordinated trafficking to the virus assembly site in the endoplasmic reticulum-Golgi intermediate compartment.

Identification of a new Pyk2 target protein with Arf-GAP activity

Protein tyrosine kinase Pyk2 is activated by a variety of G-protein-coupled receptors and by extracellular signals that elevate intracellular Ca2+ concentration. We have identified a new Pyk2 binding protein designated Pap. Pap is a multidomain protein composed of an N-terminal alpha-helical region with a coiled-coil motif, followed by a pleckstrin homology domain, an Arf-GAP domain, an ankyrin homology region, a proline-rich region, and a C-terminal SH3 domain. We demonstrate that Pap forms a stable complex with Pyk2 and that activation of Pyk2 leads to tyrosine phosphorylation of Pap in living cells. Immunofluorescence experiments demonstrate that Pap is localized in the Golgi apparatus and at the plasma membrane, where it is colocalized with Pyk2. In addition, in vitro recombinant Pap exhibits strong GTPase-activating protein (GAP) activity towards the small GTPases Arf1 and Arf5 and weak activity towards Arf6. Addition of recombinant Pap protein to Golgi preparations prevented Arf-dependent generation of post-Golgi vesicles in vitro. Moreover, overexpression of Pap in cultured cells reduced the constitutive secretion of a marker protein. We propose that Pap functions as a GAP for Arf and that Pyk2 may be involved in regulation of vesicular transport through its interaction with Pap.

Intraocular pressure in cats is lowered by drops of hornet venom

1. Nine cats were given an intravenous injection of the Oriental hornet (Vespa orientalis, Vespinae; Hymenoptera) venom sac extract (VSE) and seven cats had the same VSE administered as eye drops. 2. When injected intravenously, the hornet VSE decreased the intraocular pressure in both eyes sharply during the first 20 min and with a slower rate later on until the end of the 3 hr experiment. The intraocular pressure dropped to zero in some cases. 3. VSE eye drops decreased the intraocular pressure only in the treated eye, while in the second eye (left as a control) the intraocular pressure remained the same throughout the experiment. 4. The decrease in the intraocular pressure was sharp during the first 20 min and slowed down afterwards until the end of the experiment. 5. The intraocular pressure did not reduce to zero. 6. This study shows that the active components of the hornet venom which caused a decrease in the intraocular pressure can cross the cornea and exert a hypotensive effect in the eye.

Cavernous sinus infection manifested by Horner's syndrome and ipsilateral sixth nerve palsy

A 20-year-old man presented with a left sixth nerve paresis associated with ipsilateral Horner's syndrome several days after surgical drainage of a facial abscess. This unusual association between sixth nerve palsy and Horner's syndrome is presented and its neuroanatomic correlation is discussed.

The sacral arcuate lines in upper sacral fractures

The anteroposterior radiographs of 50 patients with multiple fractures of the pelvic ring were analyzed and the findings compared with the interpretation made at the time of admission. Thirty-six of the 50 patients (72%) had associated sacral fractures. Sixty-one percent of the sacral fractures had been missed on the initial examination. Disruption, displacement, deformity, and density changes of the sacral arcuate lines are described as signs of sacral fracture.

Gallbladder enhancement following angiography: a normal CT finding

The authors reviewed computed tomography (CT) studies that had been preceded within 2 days by angiography. Twenty-one patients were selected who showed no laboratory evidence of liver or renal disease. Eighteen patients received greater than 37 g of iodine at angiography. Eight of these underwent CT within 2 h of angiography and showed enhancement of the gallbladder wall, nine underwent CT 15 to 48 h after angiography and showed enhancement of the gallbladder contents, and one had no gallbladder enhancement. Three patients received less than 22 g of iodine at angiography and none had gallbladder enhancement on CT. The necessity of differentiating normal gallbladder enhancement from pathology on CT is stressed. In addition, the physiologic mechanisms responsible for gallbladder enhancement are presented, and the relationship of our findings to the total body opacification effect and to infusion tomography of the gallbladder is discussed.

Radiological pointers to pre-operative diagnosis of torsion of the gallbladder. A case report

A case of torsion of the gallbladder is reviewed. The radiographic features of the case suggest that in future pre-operative diagnosis may be possible with the use of ultrasound and contrast radiography.

Repeated transhepatic obliteration of gastro-oesophageal varices

Two patients with life-threatening bleeding from gastro-oesophageal varices were treated by transhepatic obliteration of the varices. The procedure was repeated in both patients on several occasions and the bleeding successfully controlled. The procedure is reviewed and the advantages, pitfalls and limitations are discussed.

Ultrasound and barium study in the evaluation of upper abdominal masses

Numerous radiological procedures are now available for investigation of upper abdominal masses of uncertain aetiology; however, certain limitations and pitfalls are associated with these procedures. It is suggested that the initial use of ultrasound and barium studies would frequently provide either a definite diagnosis or lead to the next appropriate line of investigation. The importance of not omitting the barium study is stressed.

Controlled mechanized trepan

A mechanized trepan is described whose cutting action is halted automatically when the trepan's cutting edge reaches the last 0.03 mm. tissue layer of the cornea. The automatic half of both the motor which advances the trepan as well as the second motor which rotates the trepan is triggered by the sudden change in electrical resistance between the trepan and the patient's internal body fluid, at the final stage of penetration. This automatic feature eliminates the danger of inadvertant damage to the inner structures of the eye.

Incipient histopathological lesions in citral-induced microphthalmos in chick embryos

Microphthalmos was indeed experimentally in 3-day-old chick embryos by intraamniotic injection of citral. Various degrees of this particular microphthalmic syndrome were observed. Severe cases were always accompanied by destructive changes in the ipsilateral part of the head. The corneal epithelium lost its continuity and the lens showed, even in the early stages, severe degenerative changes with spherophakia. The neural retina seemed to be affected later and showed hyperplasia and fold formation, while the retinal pigment epithelium was only mildly affected. The mesenchyme behaved differently according to its location: the superficial corneal and ciliary mesenchyme underwent hyperplasia, while the deeper choroidal mesoderm showed edematous changes only. This temporal and spatial distribution of pathological changes in the eye structures favors the assumption that citral acts locally. The experimental microphthalmic syndrome is not only due to the direct effect of the exogenous teratogenic factor on the ocular anlagen but is also the result of subsequent adaptive changes of these structures to the new environmental condition.