Agrobacterium tumefaciens-mediated transformation to alter ethylene and cytokinin biosynthesis in broccoli

Broccoli (Brassica oleracea var. italica) deteriorates rapidly following harvest. Postharvest treatment of broccoli with 6-benzylaminopurine delays senescence, whilst exogenous ethylene has been shown to accelerate this process following harvest. To alter ethylene biosynthesis, broccoli was transformed, using Agrobacterium tumefaciens-mediated transformation, with an antisense ACC oxidase gene from broccoli driven by the asparagine synthetase promoter from asparagus. In addition, broccoli was transformed with the chimeric gene construct SAG12-IPT to alter cytokinin biosynthesis during harvest-induced senescence. Transformation was achieved using both hypocotyl and cotyledonary petiole explants. The presence of an antisense ACC oxidase gene enhanced transformation efficiency, but Ag⁺ incorporated into the medium did not. The transgenic nature of these plants was confirmed by PCR and Southern analyses.     

Kryptoperidinium foliaceum blooms in South Carolina: a multi-analytical approach to identification

Observations following the discovery of Kryptoperidinium foliaceum blooms in South Carolina (SC), USA, suggest that a multi-analytical approach, using a standard, minimal set of criteria, should be adopted for determining dinoflagellate species identity and taxonomic placement. A combination of morphological, molecular, and biochemical analyses were used to determine the identity of this “red tide” dinoflagellate, first documented in SC waters in the spring of 1998. Results from thecal plate tabulations (based on scanning electron and epifluorescence microscopy), gene sequence data, species-specific PCR probe assays, and microalgal pigment profiles were analyzed and compared to reference cultures of K. foliaceum. Comparative data showed marked inconsistencies among the K. foliaceum reference culture isolates. In addition, the SC bloom isolate was shown to be mononucleate, contrary to previous reports for K. foliaceum, suggesting a more transient endosymbiotic association than previously considered.     

Effectiveness of appropriately trained nurses in preoperative assessment: randomised controlled equivalence/non-inferiority trial

ObjectiveTo determine whether preoperative assessments carried out by appropriately trained nurses are inferior in quality to those carried out by preregistration house officers.DesignRandomised controlled equivalence/non-inferiority trial.SettingFour NHS hospitals in three trusts. Three of the four were teaching hospitals.ParticipantsAll patients attending for assessment before general anaesthesia for general, vascular, urological, or breast surgery between April 1998 and March 1999.InterventionAssessment by one of three appropriately trained nurses or by one of several preregistration house officers.Results1907 patients were randomised, and 1874 completed the study; 926 were assessed by house officers and 948 by nurses. Overall 121/948 (13%) assessments carried out by nurses were judged to have possibly affected management compared with 138/926 (15%) of those performed by house officers. Nurses were judged to be non-inferior to house officers in assessment, although there was variation among them in terms of the quality of history taking. The house officers ordered considerably more unnecessary tests than the nurses (218/926 (24%) v 129/948 (14%).ConclusionsThere is no reason to inhibit the development of nurse led preoperative assessment provided that the nurses involved receive adequate training. However, house officers will continue to require experience in preoperative assessment.     

One hundred years ago: Presents from patient

ObjectiveTo compare rates of upper gastrointestinal haemorrhage among elderly patients given selective cyclo-oxygenase-2 (COX 2) inhibitors and non-selective non-steroidal anti-inflammatory drugs (NSAIDs).DesignObservational cohort study.SettingAdministrative data from Ontario, Canada, used from 17 April 2000 to 31 March 2001 to identify population based, NSAID-naive cohorts of patients.PatientsSubjects aged ⩾66 years who started taking non-selective NSAIDs (n=5391), diclofenac plus misoprostol (n=5087), rofecoxib (n=14 583), or celecoxib (n=18 908) and a randomly selected control cohort not exposed to NSAIDs (n=100 000).ResultsRelative to controls, the multivariate model revealed an increased short term risk of upper gastrointestinal haemorrhage for users of non-selective NSAIDs (adjusted rate ratio 4.0 (95% confidence intervals 2.3 to 6.9)), diclofenac plus misoprostol (3.0 (1.7 to 5.6)), and rofecoxib (1.9 (1.3 to 2.8)) but not celecoxib (1.0 (0.7 to 1.6)). Relative to celecoxib, significantly higher risks of upper gastrointestinal haemorrhage were observed for non-selective NSAIDs (4.4 (2.3 to 8.5)), diclofenac plus misoprostol (3.2 (1.6 to 6.5)), and rofecoxib (1.9 (1.2 to 2.8)). Relative to rofecoxib, non-selective NSAID users were at significantly higher risk of upper gastrointestinal haemorrhage (1.9 (1.0 to 3.5)).ConclusionsThis population based observational study found a lower short term risk of upper gastrointestinal haemorrhage for selective COX-2 inhibitors compared with non-selective NSAIDs.

What is already known on this topic

Long term NSAID use is associated with the development of peptic and duodenal ulcersSelective COX 2 inhibitors are claimed to cause fewer gastrointestinal problems than conventional, non-selective NSAIDsIt is unclear to what degree COX 2 inhibitors increase gastrointestinal risk relative to not using NSAIDs, and the relative gastrointestinal safety of the different COX 2 inhibitors is uncertain

What this study adds

The risk of upper gastrointestinal haemorrhage with the COX 2 inhibitors rofecoxib and celecoxib was significantly lower than with conventional NSAIDs, but the risk with rofecoxib was significantly higher than that with celecoxibThe risk of gastrointestinal haemorrhage with celecoxib was similar to that in controls not using NSAIDs     

Evolutionary conservation, developmental expression, and genomic mapping of mammalian Twisted gastrulation

The twisted gastrulation gene (tsg) encodes a secreted protein required for the correct specification of dorsal midline cell fate during gastrulation in Drosophila. We report that tsg homologs from human, mouse, zebrafish, and Xenopus share 72–98% identity at the amino acid level and retain all 24 cysteine residues from Drosophila. In contrast to Drosophila where tsg expression is limited to early embryos, expression is found throughout mouse and human development. In Drosophila, tsg acts in synergy with decapentaplegic (dpp), a member of the TGF-β family of secreted proteins. The vertebrate orthologs of dpp, BMP-2 and -4, are crucial for gastrulation and neural induction, and aberrant signaling by BMPs and other TGF-β family members results in developmental defects including holoprosencephaly (HPE). Interestingly, human TSG maps to the HPE4 locus on Chromosome 18p11.3, and our analysis places the gene within 5 Mbp of TG-interacting factor (TGIF). Received: 21 August 2000 / Accepted: 9 March 2001     

Religious Affiliation Modulates Weekly Cycles of Cropland Burning in Sub-Saharan Africa

Vegetation burning is a common land management practice in Africa, where fire is used for hunting, livestock husbandry, pest control, food gathering, cropland fertilization, and wildfire prevention. Given such strong anthropogenic control of fire, we tested the hypotheses that fire activity displays weekly cycles, and that the week day with the fewest fires depends on regionally predominant religious affiliation. We also analyzed the effect of land use (anthrome) on weekly fire cycle significance. Fire density (fire counts.km^-2) observed per week day in each region was modeled using a negative binomial regression model, with fire counts as response variable, region area as offset and a structured random effect to account for spatial dependence. Anthrome (settled, cropland, natural, rangeland), religion (Christian, Muslim, mixed) week day, and their 2-way and 3-way interactions were used as independent variables. Models were also built separately for each anthrome, relating regional fire density with week day and religious affiliation. Analysis revealed a significant interaction between religion and week day, i.e. regions with different religious affiliation (Christian, Muslim) display distinct weekly cycles of burning. However, the religion vs. week day interaction only is significant for croplands, i.e. fire activity in African croplands is significantly lower on Sunday in Christian regions and on Friday in Muslim regions. Magnitude of fire activity does not differ significantly among week days in rangelands and in natural areas, where fire use is under less strict control than in croplands. These findings can contribute towards improved specification of ignition patterns in regional/global vegetation fire models, and may lead to more accurate meteorological and chemical weather forecasting.     

Assessment of different sperm functional tests in golden‐headed lion tamarins (Leontopithecus chrysomelas)

The golden‐headed lion tamarin (Leontopithecus chrysomelas) is an endangered species endemic to Brazil's Atlantic Forest, a shrinking biodiversity hotspot. As in other Neotropical primates, its semen characteristics and freezability are poorly studied. Hence, reproductive technologies for callitrichids would greatly benefit from reliable methods of semen analysis. In a bid to promote reproductive research in tamarins, we validated simple and inexpensive sperm function tests that can be used to monitor sperm‐egg binding, plasma membrane and acrosome integrity, mitochondrial activity, and DNA fragmentation. Ejaculates from adult males were individually diluted and divided into control and damage‐induced aliquots, and then samples comprising assorted amounts of damaged spermatozoa were examined by organelle‐specific tests. Our findings showed that sperm‐binding in chicken egg perivitelline membrane (EPM) positively correlated with the number of spermatozoa injured by snap‐freezing. Eosin‐nigrosin (EN) and propidium iodide readings were correlated with each other, and both provided robust measurements of plasma membrane integrity. A high correlation between expected and measured amounts of acrosome‐intact spermatozoa was found using Fast Green‐Rose Bengal (FG‐RB), Coomassie Blue (CB), and FITC‐PSA stains, and all three methods exhibited comparable results. Likewise, different percentages of UV‐irradiated spermatozoa were accurately assessed for DNA integrity by Toluidine Blue (TB) and sperm chromatin dispersion (SCD) tests. Comparisons between 3,3′‐diaminobenzidine (DAB) and JC‐1 stains also indicated the reliability of the former assay to ascertain gradual increases in spermatozoa with greater mitochondrial function. These data confirmed that different parts of the tamarin spermatozoa can be simply and consistently evaluated by EPM, EN, FG‐RB, CB, TB, and DAB protocols.