Facial recognition lock technology for social care settings: A qualitative evaluation of implementation of facial recognition locks at two residential care sites

Background

There is limited literature on security and access for social care settings despite policy highlighting importance, and no published research exploring facial recognition lock technology (FRLT) for potential improvements. This study explored FRLT device implementation, use, barriers and benefits.

Methods

One residential care home with 43 older adults and 68 staff members (Site A), and one supported living facility caring for six individuals with mental health issues with 18 staff members (Site B) were provided with FRLT for six months. Nine pre-implementation staff interviews explored existing access and security perceptions. Ten post-implementation staff interviews and one staff focus group were conducted; all were analysed using content analysis to understand, alongside process mapping, the use and impact of the FRLT. Interview participants included site care staff and other visiting healthcare professionals. We additionally report feedback from the technology developers to demonstrate impact of industry-academia collaboration.

Results

Pre-implementation interviews highlighted issues with current pin-pad or lock-box systems, including; code sharing; code visibility, ineffective code changes, security issues following high staff turnover, lack of efficiency for visitors including NHS staff and lack of infection control suggesting requirement for innovation and improvement. Pre-implementation interviews showed openness and interest in FRLT, although initial queries were raised around cost effectiveness and staff skills. Following implementation, good levels of adoption were achieved with 72% and 100% (49/68 and 18/18) of staff members uploading their face at the two sites, and 100% of residents at Site B using the system (6/6). Additionally, Site B made a positive procurement decision and continues to discuss wider rollout. Post implementation interviews suggested FRLT was useful and acceptable for improving security and access. Benefits identified included staff/visitor time saving, enhanced security, team ease of access, resident autonomy and fewer shared touch points. Integration was suggested including with fire alarm systems, staff clocking in/out, and Covid monitoring to improve usefulness. The developers have since responded to feedback with design iterations.

Conclusion

We identified concerns on security and access in social care settings, which warrant further exploration and research. FRLT could increase resident autonomy and reduce staff burden, particularly considering frequent multi-agency health and care visits.

562 Biopsy of Localised Renal Masses Offers High Diagnostic Yield and Low Complication Rate in Patients with Suspicious Renal Masses

Aim

Biopsy of localised renal masses is generally accurate at detecting benign or malignant histology but can cause complications. The aim of this study was to determine the detection rate and complication rate of renal mass biopsies.

Method

Patients undergoing a renal mass biopsy at a single tertiary centre between January 2015 and December 2019 were identified electronically using a prospective database. Details about their biopsies were recorded including tumour size, radiological guidance, number of cores, longest margin of biopsy, accuracy of biopsy, histology type, and complications.

Results

This study included 334 biopsies (Median age 68 years (IQR 60-72); 61.4% (n = 204) male). Median size of tumour was 30mm (IQR 25-50) and 79.9% (n = 267) were solid masses. The biopsies were done under ultrasound (78.4%) or computed tomography (21.6%) guidance. 91.9% had core biopsies (n = 307) with median biopsy margin of 14mm (IQR 9-21). Benign histology was observed in 18.9% (n = 63), malignant in 72.1% (n = 241) while biopsy was non-diagnostic in 9.0% (n = 30). 62.6% (n = 209) of the cases were renal cell carcinoma with clear cell subtype more commonly seen (72.2%, n = 151). Complications following biopsy included haematoma (n = 7, 2.1%), haemorrhage (n = 3, 0.9%), pneumothorax (n = 1, 0.3%) and vasovagal episode (n = 1, 0.3%), resulting in an overall complication rate of 3.6%.

Conclusions

Biopsy of localised renal masses in this study showed a detection rate of 91% and complication rate of 3.6%. This study suggests renal mass biopsies have high diagnostic yield and low complication rate.

The prognosis and management of neuroendocrine neoplasms-related metastatic bone disease: lessons from clinical practice

PURPOSE

To study the evolution and optimal management of metastatic bone disease (mBD) in patients with neuroendocrine neoplasms (NENs).

METHODS

Seventy-four patients were recruited from four NEN centers in this observational multicenter study.

RESULTS

Pancreas and small bowel were the most common primaries (30 and 27%, respectively). Almost all gastrointestinal (GI)-NENs were grades 1 and 2, whereas bronchopulmonary-thymic were atypical carcinoids. Thirty-two (43%) patients had synchronous metastatic bone disease (mBD) and three patients reported bone-specific symptoms; metachronous mBD developed at a median of 35 (range: 4-395) months. Thirty-six (86%) of patients with metachronous mBD had stage IV disease at diagnosis. Somatostatin receptor functional imaging and computed tomography were the modalities mostly used for mBD identification. Fifty-two patients received assessable bone-related therapy (bisphosphonates, denosumab, local radiotherapy, and radionuclide treatment). Improvement in mBD was seen in 5, stable disease in 22, and deterioration in 25 patients. The presence of synchronous mBD and the negative outcome of bone-related therapy negatively affected overall survival (OS). In the multivariate analysis, the stronger predictor of OS was the outcome of bone-related therapy (HR: 4.753; 95% CI: 1.589-14.213). Bisphosphonates therapy was the mostly used bone-specific treatment but its monthly administration did not affect OS. At last follow-up, 39 patients were alive with OS 50 (14-463) months.

CONCLUSIONS

Early investigation for mBD offers a prognostic marker of patients with NENs, since synchronous mBD has a negative impact on survival. The outcome of bone-related therapy affects OS but the monthly administration of bisphosphonates did not show a benefit over less intense schemes.

Identification of SNPs located on BTA 6 and BTA 20 significantly associated with bovine respiratory disease in crossbred cattle

The objective of the present study was to evaluate single nucleotide polymorphisms (SNPs) located in two quantitative trait locus (QTL) regions (BTA 6 and BTA 20) that are associated with bovine respiratory disease (BRD). A population of 323 crossbred steers sired by five purebred sire breeds during 2010-2013 (Angus, Braford, Braunvieh, Charolais, and Simmental) were evaluated for BRD susceptibility during the finishing process at a commercial feedlot. A total of 21 animals representing all sire breeds were affected with BRD at some time during the finishing process over the 4-year period. Although multiple sire breeds were evaluated in the present study, no sire breed effects were detected. A total of 82 SNPs were evaluated (58 on BTA 6 and 24 on BTA 20) in the present study for potential associations with BRD incidence. When evaluating the previously described QTL regions on BTA 6, three SNPs (rs42968895, rs42823614, and rs43448463) were significantly (P < 0.05) associated with BRD incidence. Another three SNPs (rs42477340, rs42512588, and rs42524468) were identified as significantly associated with BRD on the previously described BTA 6 QTL region. For both of these regions, animals inheriting different genotypes differed in BRD incidence during the finishing period. Although multiple SNPs were identified as being significantly associated with BRD incidence in the present study, these SNP associations should be validated in larger and more diverse populations.

Putting an end to Black Wednesday: improving patient safety by achieving comprehensive trust induction and mandatory training by day 1

The term 'Black Wednesday' has been used to describe the August national changeover day, a day when a new cohort of inexperienced doctors start work, many of whom are absent from patient care to attend organisational induction and mandatory training. In this paper, we report on the development and implementation of a novel, interactive e-learning programme for induction and mandatory training for junior doctors in a district general hospital in south-west England from August 2013. This comprehensive mandatory-training programme with summative assessment saved 19.5 hours of trust time per trainee. Since the programme's inception, the completion rate has been 100% (n = 370). Subgroup analysis of starters from August 2013 (n = 141) showed that 85.7% completed by day 1 (mean time of completion 3.0 days before day 1, standard deviation 14.2 days). Importantly, 90 minutes of induction was freed on Black Wednesday, enabling earlier, ward-based clinical orientation, thereby enhancing patient safety. We believe that this is the first programme to combine induction with fully assessed, comprehensive mandatory training in a single package. Such an approach is suitable for widespread application and is to be implemented regionally.

Bring on the weekend - Improving the quality of junior doctor weekend handover

While it is widely recognised that communication and handover are a fundamental component in providing safe clinical care for hospital patients (1,2.3). The Royal College of Physicians found that the majority of hospital doctors are dissatisfied with the standard of their handovers (4). These findings were mirrored by the junior staff at the Royal United Hospital, who felt that the weekend handover was inadequate, and detrimental to patient safety.

A group of eight junior doctors at the Royal United Hospital, Bath utilised The Model For Improvement to systematically analyse and improve various aspects of the weekend handover system. Handover sheets from a subset of wards were assessed to observe direct effects of staged interventions over a nine month period, allowing small-scale testing prior to widespread implementation of a standardised intranet-based weekend handover. The effects of interventions were evaluated using a predesigned scoring system and data was collected continuously throughout the project.

Over a nine month period the quality of handovers improved significantly from 76% to 93% (p <0.01): a success which was supported by a 100% improvement in formal feedback collected from hospital doctors and highlighted by the desire of senior staff and directors to implement the system throughout the trust. Using The Model For Improvement a group of junior doctors were able to introduce and develop a standardised weekend handover system that met their requirements. A structured, efficient and auditable system has been successfully produced which improves the quality and safety of patient care.

An impedance-based process analytical technology for monitoring the lyophilisation process

The aim of this work was to develop a minimally invasive, impedance spectroscopy method as a novel process analytical technology for monitoring the freeze drying process. This involved the application of planar electrodes, mounted externally to a conventional glass freeze-drying vial, coupled to a high-impedance analyser. The pseudo-relaxation process arising from the composite impedance of the glass wall and product interface was recorded over a frequency range 10(1)-10(6)Hz for a surrogate formulation comprising 2.5% sucrose. Features of the process (i.e. the peak amplitude, C"(peak) and characteristic peak frequency, fpeak) were monitored along with the product temperature data during the entire cycle. It was demonstrated that fpeak is strongly coupled to the temperature of the product (through the dependence of the product temperature on the electrical resistance of the product) whereas C"(peak) is dependent on the extent of ice sublimation and hence can be used to measure the rate of drying and end point of primary drying. This feature provides a distinct advantage over thermocouple measurements which are restricted to end point detection only. The potential to predict the end point of a cycle from C"(peak) vs. time profiles is highlighted in this work.

Systematic review and meta-analysis of wound dressings in the prevention of surgical-site infections in surgical wounds healing by primary intention

BACKGROUND

Postoperative surgical-site infections are a major source of morbidity and cost. This study aimed to identify and present all randomized controlled trial evidence evaluating the effects of dressings on surgical-site infection rates in surgical wounds healing by primary intention; the secondary outcomes included comparisons of pain, scar and acceptability between dressings.

METHODS

Randomized controlled trials comparing alternative wound dressings, or wound dressings with leaving wounds exposed for postoperative management of surgical wounds were included in the review regardless of their language. Databases searched included the Cochrane Wounds Group Specialised Register and Central Register of Controlled Trials, Ovid MEDLINE, Ovid Embase and EBSCO CINAHL from inception to May 2011. Two authors performed study selection, risk of bias assessment and data extraction, including an assessment of surgical contamination according to the surgical procedure. Where levels of clinical and statistical heterogeneity permitted, data were pooled for meta-analysis.

RESULTS

Sixteen controlled trials with 2594 participants examining a range of wound contamination levels were included. They were all unclear or at high risk of bias. There was no evidence that any dressing significantly reduced surgical-site infection rates compared with any other dressing or leaving the wound exposed. Furthermore, no significant differences in pain, scarring or acceptability were seen between the dressings.

CONCLUSION

No difference in surgical-site infection rates was demonstrated between surgical wounds covered with different dressings and those left uncovered. No difference was seen in pain, scar or acceptability between dressings.

Assessment of uncertainties in a long range atmospheric transport model: Methodology, application and implications in a UK context

Acid deposition models are inherently simplified representations of real world behaviour and their performance is best evaluated by comparison with observations. National and international acid rain policy assessments handle observed and modelled deposition fields in different ways. Here, both the observed and modelled deposition fields are seen as uncertain and the Generalised Likelihood Uncertainty Estimation (GLUE) framework is used to choose acceptable sets of model input parameters that minimise the differences between them. These acceptable sets of model parameters are then used to estimate deposition budgets to the UK and to provide a probabilistic treatment of excess deposition over environmental quality standards (critical loads).

Characteristics of HIV-1-associated Kaposi's sarcoma among women and men in South Africa

Despite the increase of HIV-1-associated Kaposi's sarcoma (KS), little is known about HIV-associated KS in the African setting, particularly among women. A descriptive study of the demographic, clinical, immunological and virological features of AIDS-associated KS from KwaZulu-Natal, South Africa was undertaken. Consecutively, recruited patients were clinically staged; CD4/CD8 cell counts, HIV-1 viral loads and clinical parameters were evaluated. Of the 152 patients (77 male and 75 female) 99% were black. Females were significantly younger (P = 0.02) and had poorer disease prognosis (odds ratio [OR] = 2.7, 95% confidence interval [CI] = 1.4-5.4, P = 0.003) and were more likely to have extensive cutaneous KS when compared with males (OR = 3.1, 95% CI = 1.4-6.7, P = 0.003). One-third of patients had coexisting HIV-related disease, most commonly tuberculosis, and these were more frequent in females (56.7 vs. 43.3%). In conclusion, HIV-associated KS in South Africans has an equal female-to-male ratio. Females are younger and have more severe disease than males.

Transcriptional regulation of plant senescence: from functional genomics to systems biology

Leaf senescence is an active process that involves the increased expression of many hundreds of genes. Many putative transcription factors show enhanced transcription during leaf senescence in Arabidopsis and functional analysis of these should help to indicate their role in controlling gene expression during leaf senescence. In this paper, we describe the analysis of knockout insertion mutants in two different senescence-enhanced genes, one encodes a heat shock transcription factor and the other a zinc finger protein. Plants mutated in these genes show accelerated leaf senescence and reduced tolerance to drought stress, indicating that expression of these genes during senescence has a protective role to maintain viability during this essential developmental process. Analysis of gene expression changes in both mutants compared to the wild-type plants indicates an increased rate of senescence but does not show clearly the pathway that is dependent on these genes for expression. The complexities of signalling networks in plant stress and the plasticity of plant responses mean that the direct consequences of mutation are very difficult to define. The usefulness of this type of approach to address the burning question of how senescence is regulated is discussed, and an alternative approach aimed at a more global analysis of gene regulation using systems biology methods is described.

Bexarotene improves median survival (MS) in untreated, advanced NSCLC, when given in combination with carboplatin/paclitaxel

17070

Background: Bexarotene (bex) is a subclass specific, synthetic rexinoid analogue, that preferentially binds and modulates the expression of RXR subclass of receptors α, β, and γ. It induces concentration-dependent repression of multiple genes (cyclin D1/D3, total EGFR, pEGFR) inhibiting cell growth, angiogenesis, invasion and metastasis, inducing differentiation, and apoptosis in tumor cells. Several phase-I/II trials suggested increased survival in patients with advanced NSCLC. Methods: Stage-IIIB with pleural effusion & Stage-IV chemo-naïve patients, ECOG 0–2, were enrolled and treated with carboplatin IV AUC-6 d-1 and paclitaxel IV 100 mg/m2 d-1, 8, 15, every 28-d for 4 cycles. Pts were randomized using a 1:1 design to bex PO 400 mg/m2/d either concurrent (C) from Day 1 or sequential (S) at the completion of chemo, for up to a year. Results: 56 patients were enrolled; median age 62.3 (range 41–86), 48 TNM Stage IV, 38 males, 50 ECOG PS 0–1. Of 51 pts evaluable for response, 30 (58%) achieved PR (C: 15 and S: 15); 16 (31%) showed SD (C: 8 and S: 8), and 5 (9.5%) had PD (C: 3 and S: 2). Thirty-two (63%) patients have expired as of 12/31/05. Based on ITT, 40 evaluable pts showed a median TTP of 169 days (C: 166.5 and S 172); The MS for the entire group is 342 days (11.42 mo (C: 12.8 and S: 10.53). Currently, 10 pts are still alive between 407 to 1036 days from registration on the trial. The treatment was well tolerated; overall, AEs were reported in 48% of pts in the S arm and 51% in the C arm. The incidence of Gr 3–4 AEs, regardless of the treatment arm, was < 5%. There were no treatment-associated deaths. Conclusions: Our data suggests a better ORR, TTP, and improvement in MS, when bex is added to carboplatin/ paclitaxel, regardless of concurrent or sequential administration, compared with chemo alone. ORR was not compromised by bex administration and in fact it was above average reported for similar phase-II & -III studies. Toxicity is easily managed.

[Table: see text]

A novel polymorphism in the 5' flanking region of the glucose transporter (GLUT1) gene is strongly associated with diabetic nephropathy in patients with Type 1 diabetes mellitus

Glucose transporter 1 (GLUT1) activity has been implicated in renal hypertrophy and extracellular matrix formation in mesangial cells. Recent studies have suggested that polymorphisms in the GLUT1 gene are associated with susceptibility to diabetic nephropathy (DN) in patients with diabetes mellitus. In this study, a novel polymorphism (A-2841T) in the 5' flanking region of GLUT1 was examined in 288 patients with Type 1 diabetes mellitus (T1DM) and 101 normal controls. The polymorphisms were amplified and the fragment digested with the enzyme HpyCH4V. There was a highly significant increase in the frequency of the TT-2841 genotype in patients with nephropathy (n=131) compared with those with either no microvascular complications after a 20-year duration of diabetes (uncomplicated; n=72; 54.5% vs. 2.7%, chi=79.4, P<.000001). There was no difference between the uncomplicated group and those who only had retinopathy (n=50; 2.7% vs. 4.0%, respectively). The frequency in recently diagnosed patients was 17.1% and only 2.0% in normal controls. In contrast, the AA genotype was found in 13.6% of the nephropaths, 76.3% of uncomplicated, 48.0% of retinopaths, and 65% of normal controls. These results confirm previous reports of an association between the GLUT1 gene and susceptibility to DN but not retinopathy. The localisation of this polymorphism suggests that it may be involved in the expression of the gene.

[African research in odontostomatology and international cooperation]

In this study, the authors measure the efficacy of the African odonto-stomatologic research in the International Assocation for Dental Research (I.A.D.R.) and value the impact of the international cooperation upon that research. This evaluation is realized from the number of publications presented by the African countries at the congressess of I.A.D.R. The obtained results show: 1. The African odonto-stomatologic is the less successful in the world and produced, in 1997, 0.4% of the studies published on the world, 2. Some of the African countries are able to produce scientific results of International valour (South Africa, Egypt and Nigeria in a less degree). Generally, these countries work jointly with anglo-saxon universities. 3. During these last two years, Cameroon obtained very encouraging results thanks to his collaboration with the University of Bordeaux 2 (France), represented by the regretted Professeur Ph. NDOBO-EPOY.

Conversion electron cascades in 254(102)No

The spectrum of prompt conversion electrons emitted by excited 254No nuclei has been measured, revealing discrete lines arising from transitions within the ground state band. A striking feature is a broad distribution that peaks near 100 keV and comprises high multiplicity electron cascades, probably originating from M1 transitions within rotational bands built on high K states.

Prevalence, incidence, and mother-to-child transmission of HIV-1 in rural South Africa

Simple, robust approaches are needed to monitor prevalence, incidence, and mother-to-child transmission of HIV-1 in rural Africa. We have designed a method that uses antibody and viral RNA testing of dried blood spots obtained from mother-infant pairs attending routine immunisation clinics. In our study, prevalence and incidence of HIV-1 was highest in young women in their late teens and early twenties. In children born to infected mothers, prevalence increased from 14% in infants younger than 6 weeks of age to 24% at 3-6 months. The blood-spot approach is an effective method for surveillance of HIV-1 in women and children, and for early identification of incidence of this infection in women of child-bearing age.

Inflammatory cytokines enhance the interaction of Mannheimia haemolytica leukotoxin with bovine peripheral blood neutrophils in vitro

Mannheimia (Pasteurella) haemolytica A1 produces several virulence factors that play an important role in the pathogenesis of bovine pneumonic pasteurellosis. Foremost among these is a leukotoxin (LKT) that specifically kills ruminant leukocytes. Recent evidence suggests that M. haemolytica LKT binding to bovine leukocytes is mediated by the beta(2)-integrin CD11a/CD18 (lymphocyte function-associated antigen 1 [LFA-1]), which subsequently induces activation and cytolysis of these cells. Inflammatory cytokines, which are released during viral and bacterial infection, are reported to increase LFA-1 expression and conformational activation. We investigated the effects of the inflammatory cytokines interleukin-1beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha), and gamma interferon (IFN-gamma) on the interaction of M. haemolytica LKT with bovine peripheral blood neutrophils (PMNs). In this study we demonstrated, by flow cytometry, that bovine PMNs increased their binding to an anti-bovine LFA-1 monoclonal antibody (BAT75A) following in vitro incubation with IL-1beta, TNF-alpha, or IFN-gamma. Incubation with cytokines also increased CD18 expression, as assessed by real-time PCR and by Western blotting. Increased LFA-1 expression by PMNs exposed to cytokines was associated with increased LKT binding and cytotoxicity. The latter represented, at least in part, enhanced PMN apoptosis, as assessed by propidium iodine staining and caspase-3 activation. The results of this study suggest that inflammatory cytokines may play an important role in enhancing the biological response of bovine PMNs to M. haemolytica LKT.

MRSA pyomyositis complicating sickle cell anaemia

A patient being treated for sickle cell crisis developed swollen, painful, indurated, discoloured thighs after several days in hospital. Imaging revealed the presence of multiple small abscesses in the muscle and methicillin resistant Staphylococcus aureus (MRSA) was cultured from aspirated fluid. Pyomyositis usually occurs in association with damaged muscle and impaired host defences. Staphylococcus is the most frequent organism involved. It is not a common complication of sickle cell disease, although it may be under diagnosed. Availability of advanced imaging techniques facilitates early diagnosis of pyomyositis.

Mother- and father-child attachment themes in the story completions of pre-schoolers from post-divorce families: do they predict relationships with peers and teachers?

Based on Bowlby's claim that 'internal working models' of self-with-parent influence the way a child approaches relationships with others, this study examined attachment representations of 66 pre-schoolers (39 boys, 27 girls) in relation to teachers' or child-care providers' perceptions of their social competence. The study goes beyond previous related studies in three ways: (1) all children were from post-divorce families; (2) mother- and father-child representations were examined separately; and (3) teachers rated their own relationship to the child in addition to children's socially competent behaviors and behavior problems with peers. Attachment representations were assessed with an expanded version of the Attachment Story Completion Task (see Bretherton, Ridgeway, & Cassidy, 1990) adapted for children of divorce by presenting the mother and father as living in separate houses. Hierarchical regression analyses showed that children's enactments of child-mother attachment behavior in their story completions were the best predictor of boys' and girls' teacher-rated social competence. However, boys' and girls' enactments of empathy toward mother and father as well as child-father attachment themes correlated with social competence in opposite directions: For boys, these narrative enactments were related positively to social competence, while for girls, these relationships were negative. Theoretical and methodological implications of the findings for children of divorce and for assessing the working model construct are discussed.

Molecular and biochemical characterization of postharvest senescence in broccoli

Postharvest senescence in broccoli (Brassica oleracea L. var Italica) florets results in phenotypic changes similar to those seen in developmental leaf senescence. To compare these two processes in more detail, we investigated molecular and biochemical changes in broccoli florets stored at two different temperatures after harvest. We found that storage at cooler temperatures delayed the symptoms of senescence at both the biochemical and gene expression levels. Changes in key biochemical components (lipids, protein, and chlorophyll) and in gene expression patterns occurred in the harvested tissue well before any visible signs of senescence were detected. Using previously identified senescence-enhanced genes and also newly isolated, differentially expressed genes, we found that the majority of these showed a similar enhancement of expression in postharvest broccoli as in developmental leaf senescence. At the biochemical level, a rapid loss of membrane fatty acids was detected after harvest, when stored at room temperature. However, there was no corresponding increase in levels of lipid peroxidation products. This, together with an increased expression of protective antioxidant genes, indicated that, in the initial stages of postharvest senescence, an orderly dismantling of the cellular constituents occurs, using the available lipid as an energy source. Postharvest changes in broccoli florets, therefore, show many similarities to the processes of developmental leaf senescence.

Metabolic approaches to the treatment of autism spectrum disorders

Although the exact prevalence of metabolic abnormalities in autism spectrum disorders is unknown, several metabolic defects have been associated with autistic symptoms. These include phenylketonuria, histidinemia, adenylosuccinate lyase deficiency, dihydropyrimidine dehydrogenase deficiency, 5'-nucleotidase superactivity, and phosphoribosylpyrophosphate synthetase deficiency. When the metabolic consequences of an enzyme defect are well defined (e.g., phenylketonuria, 5'-nucleotidase superactivity), treatment with diet, drugs, or nutritional supplements may bring about a dramatic reduction in autistic symptoms. This review evaluates evidence for metabolic etiologies in autism spectrum disorders, as well as for the efficacy of dietary and vitamin treatments. The relationship between gastrointestinal abnormalities and autism spectrum disorders is also considered.

Salicylic acid has a role in regulating gene expression during leaf senescence

Leaf senescence is a complex process that is controlled by multiple developmental and environmental signals and is manifested by induced expression of a large number of different genes. In this paper we describe experiments that show, for the first time, that the salicylic acid (SA)-signalling pathway has a role in the control of gene expression during developmental senescence. Arabidopsis plants defective in the SA-signalling pathway (npr1 and pad4 mutants and NahG transgenic plants) were used to investigate senescence-enhanced gene expression, and a number of genes showed altered expression patterns. Senescence-induced expression of the cysteine protease gene SAG12, for example, was conditional on the presence of SA, together with another unidentified senescence-specific factor. Changes in gene expression patterns were accompanied by a delayed yellowing and reduced necrosis in the mutant plants defective in SA-signalling, suggesting a role for SA in the cell death that occurs at the final stage of senescence. We propose the presence of a minimum of three senescence-enhanced signalling factors in senescing leaves, one of which is SA. We also suggest that a combination of signalling factors is required for the optimum expression of many genes during senescence.

Purine metabolism abnormalities in a hyperuricosuric subclass of autism

A subclass of patients with classic infantile autism have uric acid excretion which is >2 S.D.s above the normal mean. These hyperuricosuric autistic individuals may comprise approx. 20% of the autistic population. In order to determine the metabolic basis for urate overexcretion in these patients, de novo purine synthesis was measured in the cultured skin fibroblasts of these patients by quantification of the radiolabeled purine compounds produced by incubation with radiolabeled sodium formate. For comparison, de novo purine synthesis in normal controls, in normouricosuric autistic patients, and cells from patients with other disorders in which excessive uric acid excretion is seen was also measured. These experiments showed that de novo purine synthesis is increased approx. 4-fold in the hyperuricosuric autistic patients. This increase was less than that found in other hyperuricosuric disorders. No unusual radiolabeled compounds (such as adenylosuccinate) were detected in these experiments, and no gross deficiencies of radiolabeled nucleotides were seen. However, the ratio of adenine to guanine nucleotides produced by de novo synthesis was found to be lower in the cells of the hyperuricosuric autistic patients than in the normal controls or the cells from patients with other disorders. These results indicate that the hyperuricosuric subclass of autistic patients have increased de novo purine synthesis, and that the increase is approximately that expected for the degree of urate overexcretion when compared to other hyperuricosuric disorders. No particular enzyme defect was suggested by either gross deficiency of a radiolabeled compound or the appearance of an unusual radiolabeled compound, and no potentially neurotoxic metabolites were seen. Although an enzyme defect responsible for the accelerated purine synthesis was not identified, the abnormal ratio of adenine to guanine nucleotides suggests a defect in purine nucleotide interconversion.

The DIF1 gene of Arabidopsis is required for meiotic chromosome segregation and belongs to the REC8/RAD21 cohesin gene family

Cohesins are a group of conserved proteins responsible for cohesion between replicated sister chromatids during mitosis and meiosis and which are implicated in double-strand break repair and meiotic recombination. We describe here the identification and characterisation of an Arabidopsis gene - DETERMINATE, INFERTILE1 (DIF1), which is a homolog of the Schizosaccharomyces pombe REC8/RAD21 cohesin genes, and is essential for meiotic chromosome segregation. Five independent alleles of the DIF1 gene were isolated by transposon mutagenesis, and the mutants show complete male and female sterility. Pollen mother cells (PMCs) of dif1 mutants show multiple meiotic defects which are represented by univalent chromosomes and chromosome fragmentation at metaphase I, and acentric fragments and chromatin bridges in meiosis I and II. Consequently, chromosome segregation is strongly affected, resulting in meiotic products of uneven size, shape and of variable ploidy. The similarities in phenotype, and the sequence homology between DIF1 and the REC8/RAD21 cohesins suggests that cohesin function is largely conserved between eukaryotes and highlights the essential role cohesins play in plant meiosis.

Genetic interactions of the Arabidopsis flowering time gene FCA, with genes regulating floral initiation

The genes controlling the timing of the transition from vegetative to reproductive growth are likely candidates for regulators of genes initiating floral development. We have investigated the interaction of one particular gene controlling flowering time, FCA, with the meristem identity-genes TERMINAL FLOWER 1 (TFL1), APETALA 1 (AP1) and LEAFY (LFY) and the floral repression gene EMBRYONIC FLOWER 1 (EMF1). Double mutant combinations were generated and the phenotypes characterized. The influence of strong and intermediate fca mutant alleles on the phenotype conferred by a 35S-LFY transgene was also analysed. The results support a model where FCA function promotes flowering in multiple pathways, one leading to activation of LFY and AP1, and another acting in parallel with LFY and AP1. Only the latter pathway is predicted to be non-functional in the intermediate fca-4 allele. The results are also consistent with AP1 and TFL1 negatively regulating FCA function. Combination of Columbia fca and emf1 mutant alleles confirmed that FCA is required for the early flowering of emf1. EMF1 and FCA are therefore likely to operate in different floral pathways.

Simple high-performance liquid chromatography method for the simultaneous determination of serum caffeine and paraxanthine following rapid sample preparation

A simple reversed-phase high-performance liquid chromatography (HPLC) method for the simultaneous determination of caffeine and paraxanthine in human serum is described. Serum proteins are precipitated with perchloric acid and the resulting supernatant neutralized for direct injection onto an HPLC column. The method uses a phosphate-methanol mobile phase (85:15, v/v) at pH 4.9 with a flow-rate of 1.75 ml/min and quantitation is by UV absorbance at 274 nm. Elution times are approximately 18 min for caffeine and 8 min for paraxanthine. Theobromine and theophylline have elution times of 5.4 and 9.4 min and do not interfere in the assay. The intra-assay and between-assay means for precision and accuracy for both drugs are: 4.5% C.V. and 3.3% deviation. The sensitivity of the method is 50 ng/ml for each drug.

Glucose-lowering effect of BTS 67 582

1. The hypoglycaemic effect of BTS 67 582 (1,1-dimethyl-2(2-morpholinophenyl) guanidine fumarate) was studied in normal rats. 2. BTS 67 582 (100 mg kg(-1), p.o.) acutely lowered basal plasma glucose concentrations: onset within 1 h, maximum decrease of >40% at 2-3 h, and partial return to euglycaemia by 5 h. Plasma insulin concentrations were increased: onset within 30 min, maximum increase 3 fold at 1-2 h; returning to normal by 5 h. 3. BTS 67 582 (100 mg kg(-1)) increased (by 56%) the rate of disappearance of plasma glucose during an intravenous glucose tolerance test, accompanied by a 51% increase in insulin concentrations. 4. During hyperglycaemic clamp studies BTS 67 582 (100 mg kg(-1)) increased glucose utilization 3 fold. This was associated with a 3 fold increase in insulin concentrations, even in the presence of adrenaline at a dosage which inhibits glucose-induced insulin release. 5. When the insulin-releasing effect of BTS 67 582 (100 mg kg(-1)) was inhibited by infusion of somatostatin, there was no effect on glycaemia. 6. Insulin-dependent diabetic BB/S rats, which do not produce endogenous insulin, showed no effect of BTS 67 582 (100 mg kg(-1)) on plasma glucose concentrations in the presence or absence of exogenous insulin. 7. The results demonstrate an acute hypoglycaemic effect of BTS 67 582 which appears to result mainly from its potent insulin-releasing action.

Developmental disorder associated with increased cellular nucleotidase activity

Four unrelated patients are described with a syndrome that included developmental delay, seizures, ataxia, recurrent infections, severe language deficit, and an unusual behavioral phenotype characterized by hyperactivity, short attention span, and poor social interaction. These manifestations appeared within the first few years of life. Each patient displayed abnormalities on EEG. No unusual metabolites were found in plasma or urine, and metabolic testing was normal except for persistent hypouricosuria. Investigation of purine and pyrimidine metabolism in cultured fibroblasts derived from these patients showed normal incorporation of purine bases into nucleotides but decreased incorporation of uridine. De novo synthesis of purines and cellular phosphoribosyl pyrophosphate content also were moderately decreased. The distribution of incorporated purines and pyrimidines did not reveal a pattern suggestive of a deficient enzyme activity. Assay of individual enzymes in fibroblast lysates showed no deficiencies. However, the activity of cytosolic 5'-nucleotidase was elevated 6- to 10-fold. Based on the possibility that the observed increased catabolic activity and decreased pyrimidine salvage might be causing a deficiency of pyrimidine nucleotides, the patients were treated with oral pyrimidine nucleoside or nucleotide compounds. All patients showed remarkable improvement in speech and behavior as well as decreased seizure activity and frequency of infections. A double-blind placebo trial was undertaken to ascertain the efficacy of this supplementation regimen. Upon replacement of the supplements with placebo, all patients showed rapid regression to their pretreatment states. These observations suggest that increased nucleotide catabolism is related to the symptoms of these patients, and that the effects of this increased catabolism are reversed by administration of uridine.

Microplate assay of ascorbic acid in aqueous humor with bicinchoninic acid

An inexpensive microplate assay method was developed to determine ascorbic acid in human aqueous humor samples. The method is based on the selective oxidation of ascorbic acid at alkaline pH and determination of ascorbic acid and other reducing substances in samples with bicinchoninic acid/CuSO4 before and after the alkaline treatment. The two-point measurement eliminates the effect of interfering substances, such as glucose, uric acid and glutathione, which are stable at alkaline pH. The advantages of the method are that it requires small sample volumes and allows handling of a large number of samples simultaneously.

FCA, a gene controlling flowering time in Arabidopsis, encodes a protein containing RNA-binding domains

A strong promoter of the transition to flowering in Arabidopsis is encoded by FCA. FCA has been cloned and shown to encode a protein containing two RNA-binding domains and a WW protein interaction domain. This suggests that FCA functions in the posttranscriptional regulation of transcripts involved in the flowering process. The FCA transcript is alternatively spliced with only one form encoding the entire FCA protein. Plants carrying the FCA gene fused to the strong constitutive 35S promoter flowered earlier, and the ratio and abundance of the different FCA transcripts were altered. Thus, FCA appears to be a component of a posttranscriptional cascade involved in the control of flowering time.

Increased Ac excision (iae): Arabidopsis thaliana mutations affecting Ac transposition

The maize transposable element Ac is highly active in the heterologous hosts tobacco and tomato, but shows very much reduced levels of activity in Arabidopsis. A mutagenesis experiment was undertaken with the aim of identifying Arabidopsis host factors responsible for the observed low levels of Ac activity. Seed from a line carrying a single copy of the Ac element inserted into the streptomycin phosphotransferase (SPT) reporter fusion, and which displayed typically low levels of Ac activity, were mutagenized using gamma rays. Nineteen mutants displaying high levels of somatic Ac activity, as judged by their highly variegated phenotypes, were isolated after screening the M2 generation on streptomycin-containing medium. The mutations fall into two complementation groups, iae1 and iae2, are unlinked to the SPT::Ac locus and segregate in a Mendelian fashion. The iae1 mutation is recessive and the iae2 mutation is semi-dominant. The iae1 and iae2 mutants show 550- and 70-fold increases, respectively, in the average number of Ac excision sectors per cotyledon. The IAE1 locus maps to chromosome 2, whereas the SPT::Ac reporter maps to chromosome 3. A molecular study of Ac activity in the iae1 mutant confirmed the very high levels of Ac excision predicted using the phenotypic assay, but revealed only low levels of Ac re-insertion. Analyses of germinal transposition in the iae1 mutant demonstrated an average germinal excision frequency of 3% and a frequency of independent Ac re-insertions following germinal excision of 22%. The iae mutants represents a possible means of improving the efficiency of Ac/Ds transposon tagging systems in Arabidopsis, and will enable the dissection of host involvement in Ac transposition and the mechanisms employed for controlling transposable element activity.

Purification and characterization of human lymphoblast N-acetylglucosamine-1-phosphodiester alpha-N-acetylglucosaminidase

The enzyme N-acetylglucosamine-1-phosphodiester alpha-N-acetylglucosaminidase (EC 3.1.4.45; uncovering enzyme) catalyzed the removal of N-acetylglucosamine from the N-acetylglucosamine-alpha-phospho-mannose portion of selected lysosomal enzyme oligosaccharide chains, thereby forming the mannose 6-phosphate signal which is responsible for the targeting of these lysosomal enzymes for transport into lysosomes. The uncovering enzyme has been purified approximately 7000-fold to electrophoretic homogeneity from Epstein-Barr virus-transformed human lymphoblast cells. The purification sequence involves solubilizing this membrane-bound enzyme with Tergitol NP-10, affinity chromatography on Lentil lectin-Sepharose 4B, ion-exchange chromatography on DEAE-Sephacel, chromatography on zinc(II)-IDA-Sepharose 6B, and preparative SDS-PAGE electrophoresis. The purified enzyme migrated as a single band of 114 kDa which was coincident with enzyme activity on analytical SDS-PAGE electrophoresis. Characterization studies of the purified enzyme demonstrated that catalytic activity was maximal at pH 6.95 and that the enzyme retained full activity following incubation for 10 min at 60 degrees C. No requirement was found for a divalent cation, but Zn2+, Hg2+, and Cu2+ were found to reduce the enzyme's activity by 30-40%. The highest catalytic efficiency was observed with N-acetylglucosamine-phospho-methylmannoside as a substrate while uridine diphosphate-N-acetylglucosamine, N-acetylglucosamine-phosphomannose-uteroferrin, and N-acetylglucosamine-phosphate were also cleaved by the enzyme with decreasing efficiency. Acetamino-deoxycastanospermine was a potent inhibitor of the human enzyme with a Ki of 0.35 microM, while N-acetylglucosamine phosphate (Ki 1.58 mM) and N-acetylglucosamine (Ki 5.1 mM) inhibited the enzyme to a lesser degree.