Intermittent actuation attenuates fibrotic behaviour of myofibroblasts

The foreign body response (FBR) to implanted materials culminates in the deposition of a hypo-permeable, collagen rich fibrotic capsule by myofibroblast cells at the implant site. The fibrotic capsule can be deleterious to the function of some medical implants as it can isolate the implant from the host environment. Modulation of fibrotic capsule formation has been achieved using intermittent actuation of drug delivery implants, however the mechanisms underlying this response are not well understood. Here, we use analytical, computational, and in vitro models to understand the response of human myofibroblasts (WPMY-1 stromal cell line) to intermittent actuation using soft robotics and investigate how actuation can alter the secretion of collagen and pro/anti-inflammatory cytokines by these cells. Our findings suggest that there is a mechanical loading threshold that can modulate the fibrotic behaviour of myofibroblasts, by reducing the secretion of soluble collagen, transforming growth factor beta-1 and interleukin 1-beta, and upregulating the anti-inflammatory interleukin-10. By improving our understanding of how cells involved in the FBR respond to mechanical actuation, we can harness this technology to improve functional outcomes for a wide range of implanted medical device applications including drug delivery and cell encapsulation platforms. STATEMENT OF SIGNIFICANCE: A major barrier to the successful clinical translation of many implantable medical devices is the foreign body response (FBR) and resultant deposition of a hypo-permeable fibrotic capsule (FC) around the implant. Perturbation of the implant site using intermittent actuation (IA) of soft-robotic implants has previously been shown to modulate the FBR and reduce FC thickness. However, the mechanisms of action underlying this response were largely unknown. Here, we investigate how IA can alter the activity of myofibroblast cells, and ultimately suggest that there is a mechanical loading threshold within which their fibrotic behaviour can be modulated. These findings can be harnessed to improve functional outcomes for a wide range of medical implants, particularly drug delivery and cell encapsulation devices.

MEDICINE AND THE LAW

Dolutegravir (DTG) is a pivotal antiretroviral medicine that has become the backbone of several HIV programmes, especially in sub-Saharan African countries. It has recently replaced efavirenz as the preferred third drug for people initiating antiretroviral therapy in South Africa (SA). Its tolerability, cost-effectiveness and favourable resistance profile have had a global influence on HIV management, including the recent revision of the World Health Organization antiretroviral guidelines. As with any medicine, however, informed decisions are important. Despite the several advantages DTG offers, additional data informing risks over benefits have emerged that warrant clinical attention before DTG is prescribed. This article aims to give the primary care provider an overview of the benefits and risks associated with the roll-out of DTG in SA.

Maternity services response to the COVID-19 pandemic: how Public Health England guidance was implemented in practice

Introduction

The rapidly evolving COVID-19 pandemic required systemic change in how healthcare was delivered to minimize virus transmission whilst maintaining safe service delivery. Deemed at ‘moderate-high risk’, maternity patients are an important patient group that require consideration. Public Health England (PHE) issued national guidance on how to adjust these services.

Aim

To explore how maternity units in England implemented PHE guidance.

Methods

An online survey of 22 items was distributed to individuals that had worked on an England-based maternity unit during the COVID-19 pandemic. The questionnaire was designed and tested by the multidisciplinary research team. Data was collected from November 2020 to July 2021.

Findings

Forty-four participants across 33 maternity units responded. Ninety-three percent were able to test all women requiring an overnight stay for COVID-19. Only 27% reported birth partners were tested for COVID-19. Only 73% reported they were able to isolate all COVID-19-positive patients in single rooms. Eighty-four percent stated they were aware of current PHE guidance on personal protective equipment (PPE) and 82% felt ‘confident’ in donning/doffing of PPE. Priorities for the future include rapid testing and a focus on community service provision.

Conclusions

PHE COVID-19 guidance was implemented differently in maternity units across England due to the varying resources available at each trust leading to variable ability to test and isolate patients as recommended. More specific, tailored guidance for infection control measures against COVID-19 is needed for maternity settings due to their unique position.

A cellular and molecular analysis of SoxB-driven neurogenesis in a cnidarian

Neurogenesis is the generation of neurons from stem cells, a process that is regulated by SoxB transcription factors (TFs) in many animals. Although the roles of these TFs are well understood in bilaterians, how their neural function evolved is unclear. Here, we use Hydractinia symbiolongicarpus, a member of the early-branching phylum Cnidaria, to provide insight into this question. Using a combination of mRNA in situ hybridization, transgenesis, gene knockdown, transcriptomics, and in vivo imaging, we provide a comprehensive molecular and cellular analysis of neurogenesis during embryogenesis, homeostasis, and regeneration in this animal. We show that SoxB genes act sequentially at least in some cases. Stem cells expressing Piwi1 and Soxb1, which have broad developmental potential, become neural progenitors that express Soxb2 before differentiating into mature neural cells. Knockdown of SoxB genes resulted in complex defects in embryonic neurogenesis. Hydractinia neural cells differentiate while migrating from the aboral to the oral end of the animal, but it is unclear whether migration per se or exposure to different microenvironments is the main driver of their fate determination. Our data constitute a rich resource for studies aiming at addressing this question, which is at the heart of understanding the origin and development of animal nervous systems.

Transcription factor AP2 controls cnidarian germ cell induction

Clonal animals do not sequester a germ line during embryogenesis. Instead, they have adult stem cells that contribute to somatic tissues or gametes. How germ fate is induced in these animals, and whether this process is related to bilaterian embryonic germline induction, is unknown. We show that transcription factor AP2 (Tfap2), a regulator of mammalian germ lines, acts to commit adult stem cells, known as i-cells, to the germ cell fate in the clonal cnidarian Hydractinia symbiolongicarpus Tfap2 mutants lacked germ cells and gonads. Transplanted wild-type cells rescued gonad development but not germ cell induction in Tfap2 mutants. Forced expression of Tfap2 in i-cells converted them to germ cells. Therefore, Tfap2 is a regulator of germ cell commitment across germ line-sequestering and germ line-nonsequestering animals.

Primary prevention of cardiovascular disease in South African women living with HIV

The colliding epidemics of HIV and cardiovascular disease (CVD) are of great public health concern. People living with HIV (PLHIV) are more predisposed to CVD development as a result of a multitude of contributors. Women living with HIV (WLHIV) appear to be at a higher risk of developing CVD given a heightened immune activation and, in South Africa particularly, a higher body mass index compared with their male counterparts. The World Health Organization (WHO) has made recommendations for the provision of a CVD risk assessment for all PLHIV and has developed regional CVD prediction charts to identify PLHIV who may require primary prevention strategies by means of interventions such as the WHO Package of Essential Non-communicable Disease Interventions for primary health care in low-resource settings (WHO PEN). However, methods of risk prediction and risk reduction integrated strategies for atherosclerotic CVD in PLHIV such as the WHO PEN, particularly in women who may have sex-specific risk factors and culture-specific perceptions of body image, remain a major research gap in developing countries. Further research is crucial in guiding primary health care policy in South Africa.

Bioavailability in Rats of Human Recombinant Tissue Plasminogen Activator After Subcutaneous and Intramuscular Injection

The bioavailability of human recombinant tissue plasminogen activator (rt-PA) in rats was measured after subcutaneous (s.c.) and intramuscular (i.m.) injection. Rt-PA was absorbed after both i.m. and s.c. injection, giving peak plasma concentrations within 30 min and 1 h, respectively, with detectable concentrations up to 6 h. These peak values of bioavailable t-PA were obtained in a functional fibrin plate assay of euglobulin precipitates and expressed as +88% and +243% (for s.c. and i.m. routes respectively) above basal rat fibrinolytic activity. Prior injection of rt-PA, s.c. or i.m., significantly reduced the weights of thrombi induced in the inferior vena cava after injection.

The Efficacy of Budesonide and Beclomethasone Dipropionate, Delivered via a Pressurized Metered Dose Inhaler, in the Treatment of Perennial Rhinitis: A Randomized, Double-Blind, Crossover Study

A total of 28 adult patients (19 women, nine men; mean age 28.5 years, range 15–63 years) with a diagnosis of perennial allergic and nonallergic rhinitis (mean duration of symptoms 4.0 years, range 1–20 years) were recruited into this randomized, double-blind, crossover study. Eighteen patients (64%) were atopic for common allergens. The efficacy of budesonide nasal aerosol (Rhinocort®) and beclomethasone dipropionate (BDP; Beconase®) was compared using nominal doses of 200 μg (b.i.d.) for each drug administered every morning and evening. Following a 2-week run-in period, patients were randomly-divided into two groups and treated for 4 weeks with either BDP or budesonide. After the crossover, patients then received the second drug for the remaining 4 weeks of the trial. Response to the treatment regimens was assessed by subjective symptom scoring and nasal peak expiratory flow rate (PEF) measurements. Budesonide and BDP reduced all nasal symptom scores and improved nasal PEF compared to the run-in period. During budesonide therapy, significantly less sleep disturbance, lower evening and morning nasal blockage scores, and greater nasal PEF values in the evening were recorded than for BDP. Following crossover, patients who were treated with budesonide in the second part of the trial demonstrated significantly improved nasal blockage scores and evening nasal PEF in contrast to those who received BDP during the latter part of the study. The number of adverse events reported during the trial was equal for both drugs and those noted tended to be mild. In conclusion, although the symptoms of perennial rhinitis were well controlled by both budesonide and BDP, the predominant symptom of nasal blockage was managed more effectively with budesonide.

Algorithm that delivers an individualized rapid-acting insulin dose after morning resistance exercise counters post-exercise hyperglycaemia in people with Type 1 diabetes

AIMS

To develop an algorithm that delivers an individualized dose of rapid-acting insulin after morning resistance exercise to counter post-exercise hyperglycaemia in individuals with Type 1 diabetes.

METHODS

Eight people with Type 1 diabetes, aged 34 ± 7 years with HbA1c concentrations 72 ± 12 mmol/mol (8.7 ± 1.1%), attended our laboratory on two separate mornings after fasting, having taken their usual basal insulin the previous evening. These people performed a resistance exercise session comprising six exercises for two sets of 10 repetitions at 60% of the maximum amount of force that was generated in one maximal contraction (60% 1RM). In a randomized and counterbalanced order, the participants were administered an individualized dose of rapid-acting insulin (2 ± 1 units, range 0-4 units) immediately after resistance exercise (insulin session) by means of an algorithm or were not administered this (no-insulin session). Venous blood glucose concentrations were measured for 125 min after resistance exercise. Data (mean ± sem values) were analysed using anova (P ≤ 0.05).

RESULTS

Participants had immediate post-resistance exercise hyperglycaemia (insulin session 13.0 ± 1.6 vs. no-insulin session 12.7 ± 1.5 mmol/l; P = 0.834). The decline in blood glucose concentration between peak and 125 min after exercise was greater in the insulin exercise session than in the no-insulin session (3.3 ± 1.0 vs. 1.3 ± 0.4 mmol/l: P = 0.015). There were no episodes of hypoglycaemia (blood glucose <3.9 mmol/l).

CONCLUSIONS

Administration of rapid-acting insulin according to an individualized algorithm reduced the hyperglycaemia associated with morning resistance exercise without causing hypoglycaemia in the 2 h post-exercise period in people with Type 1 diabetes.

Isolation, selection and culture methods to enhance clonogenicity of mouse bone marrow derived mesenchymal stromal cell precursors

Introduction

Conventionally cultured mouse bone marrow mesenchymal stromal cells (mBM-MSC) are a heterogeneous population that often initially contain contaminating haematopoietic cells. Variability in isolation methods, culture protocols and the lack of specific mBM MSC markers might explain this heterogeneity. The aim of this study is to optimise the isolation, culture conditions and selection of mBM-MSC.

Methods

Mouse BM-MSCs were isolated from crushed long bones (cBM) or flushed bone marrow (fBM) from 6–8 week old C57Bl/6 mice. These subpopulations were analysed by flow cytometry using commonly used mBM-MSC cell surface marker, e.g. Sca-1, CD29 and CD44. Cells were cultured and expanded in vitro in hypoxic conditions of either 2 % or 5 % oxygen. Cell sorting and qRT-PCR was used to determine transcript levels of stem cell and lineage related genes in individual subpopulations.

Results

During early passaging not only do contaminating haematopoietic cells disappear, but there is a change in the phenotype of mBM-MSC affecting particularly CD44 and Sca-1 expression. By fluorescence activated cell sorting of CD45⁻/Ter119⁻ mBM stroma based on Sca-1 expression and expansion in hypoxic conditions, we show that Sca-1⁺ cells had higher CFU-F frequencies and showed enhanced proliferation compared with Sca-1⁻ cells. As evaluated by in vitro assays and qRT-PCR, these cells presented in vitro tri-lineage differentiation along osteocyte, chondrocyte, and adipocyte lineages. Finally, by prospective isolation of Sca-1⁺PDGFRα⁺CD90⁺ cells we have isolated mBM-MSC on a single cell level, achieving a CFU-F frequency of 1/4. Functional investigations demonstrated that these MSC clones inhibited T-lymphocyte proliferation.

Conclusion

By positive selection using a combination of antibodies to Sca-1, CD90 and PDGFRα and culturing in hypoxia, we have found a subpopulation of BM cells from C57Bl/6 mice with a CFU-F cloning efficiency of 1/4. To our knowledge these results represent the highest frequencies of mouse MSC cloning from C57Bl/6 mice yet reported.

Electronic supplementary material

The online version of this article (doi:10.1186/s13287-015-0139-5) contains supplementary material, which is available to authorized users.

Similar magnitude of post-exercise hyperglycemia despite manipulating resistance exercise intensity in type 1 diabetes individuals

The aim of this study was to compare the glycemic and glucoregulatory hormone responses to low- and moderate-intensity morning resistance exercise (RE) sessions in type 1 diabetes (T1DM). Following maximal strength assessments (1RM), eight T1DM (HbA1C :72 ± 12 mmol/mol, age:34 ± 7 years, body mass index:25.7 ± 1.6 kg/m(2) ) participants attended the research facility on two separate occasions, having fasted and taken their usual basal insulin but omitting rapid-acting insulin. Participants performed six exercises for two sets of 20 repetitions at 30%1RM during one session [low-intensity RE session (LOW)] and two sets of 10 repetitions at 60%1RM during another session [moderate-intensity RE session (MOD)], followed by 65-min recovery. Sessions were matched for total mass lifted (kg). Venous blood samples were taken before and after exercise. Data (mean ± SEM) were analyzed using analysis of variance (P ≤ 0.05). There were no hypoglycemic occurrences throughout the study. Blood glucose rose similarly between sessions during exercise (P = 0.382), remaining comparable between sessions throughout recovery (P > 0.05). There was no effect of RE intensity on metabolic acidosis (P > 0.05) or peak growth hormone responses (P = 0.644), but a tendency for greater catecholamine responses under LOW (individualized peak concentrations: adrenaline MOD 0.55 ± 0.13 vs LOW 1.04 ± 0.37 nmol/L, P = 0.155; noradrenaline MOD 4.59 ± 0.86 vs LOW 7.11 ± 1.82 nmol/L, P = 0.082). The magnitude of post-exercise hyperglycemia does not differ between equal volume low and moderate intensity RE sessions performed in the morning.

High HPV vaccination uptake rates for adolescent girls after regional governmental funding in Shiki City, Japan

BACKGROUND

In Japan, the bivalent HPV vaccine was approved in October, 2009 and became available as a non-routine vaccine from December, 2009. While routine vaccinations are free, the cost and responsibility for non-routine vaccinations are left to the individual. In exceptional circumstances regional governments fund non-routine vaccinations. This was the case in Shiki City, Saitama Prefecture, where a high uptake rate for individual (non-school based) HPV vaccination was obtained.

MATERIALS

On January 20, 2010, the mayor of Shiki City announced to the media his decision to vaccinate adolescent girls in Shiki City against HPV. A project team for HPV vaccination was set up in the city's Health Promotion Center. To gain mutual consent for HPV vaccination, senior health professionals, city officials, the head of the board of education, school principals and health-care teachers met several times. The cohort to be vaccinated was 1254 girls aged 12-15 years. Individual notifications were mailed to each girl on April 23, 2010, along with information about the HPV vaccine.

CONCLUSIONS

As of April 10th, 2011, the uptake rate for girls aged 15 years old was 90.7% for the 1st dose. The vaccine registry is managed by the health care system of the city. The success of the HPV vaccination program and high uptake rates in Shiki City is a good model for the nationwide HPV vaccination program that started in February, 2011.

Evidence-based practice in school substance use prevention: fidelity of implementation under real-world conditions

Fidelity of program implementation under real-world conditions is a critical issue in the dissemination of evidence-based school substance use prevention curricula. Program effects are diminished when programs are implemented with poor fidelity. We assessed five domains of fidelity--adherence, exposure (dosage), quality of delivery, participant responsiveness and program differentiation (lack of contamination from other programs)--in a subset of respondents (N = 342) from a national random sample of public schools with middle school grades (N = 1721). Respondents taught 1 of 10 evidence-based universal substance use prevention programs as their primary program during the 2004-05 school year. Their responses to survey questions about their recent implementation practices indicated that fidelity was high for quality of delivery and participant responsiveness, low for program differentiation and modest for adherence and exposure--the two core domains of fidelity. Results suggest the need for continued emphasis on fidelity in program materials, trainings and on-going technical support. Particular attention should be paid to supporting use of interactive delivery strategies.

An anchored linkage map for sugar beet based on AFLP, SNP and RAPD markers and QTL mapping of a new source of resistance to Beet necrotic yellow vein virus

Rhizomania, caused by Beet necrotic yellow vein virus (BNYVV), is an important sugar-beet disease worldwide and can result in severe losses of root yield and sugar content. We have identified a major QTL for BNYVV resistance from a new source in a segregating population of 158 individuals. The QTL explained an estimated 78% of the observed phenotypic variation and the gene conferring the partial resistance is referred to as Rz4. AFLP was used in combination with bulked segregant analysis (BSA) to develop markers linked to the resistance phenotype. AFLP marker analysis was extended to produce a linkage map that was resolved into nine linkage groups. These were anchored to the nine sugar-beet chromosomes using previously published SNP markers. This represents the first anchored sugar-beet linkage map to be published with non-anonymous markers. The final linkage map comprised 233 markers covering 497.2 cM, with an average interval between markers of 2.1 cM. The Rz4 QTL and an Rz1 RAPD marker were mapped to chromosome III, the known location of the previously identified BNYVV resistance genes Rz1, Rz2 and Rz3. The availability to breeders of new resistance sources such as Rz4 increases the potential for breeding durable disease resistance.

Autocrine insulin action activates Akt and increases survival of isolated human islets

AIMS/HYPOTHESIS

The phosphatidylinositol 3-kinase (PI3K)/Akt pathway plays a critical role in promoting the survival of pancreatic beta cells. Akt becomes activated in isolated human islets following overnight culture despite significant levels of cell death. The aim of the current study was to identify the cause of the observed increase in Akt phosphorylation in isolated islets. We hypothesised that a factor secreted by the islets in culture was acting in an autocrine manner to activate Akt.

METHODS

In order to identify the stimulus of the PI3K/Akt pathway in culture, we examined the effects of different culture conditions on Akt phosphorylation and islet survival during the immediate post-isolation period.

RESULTS

We demonstrated that islet-conditioned medium induced Akt phosphorylation in freshly isolated human islets, whereas frequent medium replacement decreased Akt phosphorylation. Following overnight culture, islet-conditioned medium contained significantly elevated levels of insulin, indicating that insulin may be responsible for the observed increase in Akt phosphorylation. Indeed, treatment with an anti-insulin antibody or with inhibitors of insulin receptor/IGF receptor 1 kinase activity suppressed Akt phosphorylation, leading to decreased islet survival. In addition, dispersion of islets into single cells also suppressed Akt phosphorylation and induced islet cell death, indicating that islet integrity is also required for maximal Akt phosphorylation.

CONCLUSIONS/INTERPRETATION

Our findings demonstrate that insulin acts in an autocrine manner to activate Akt and mediate the survival of isolated human islets. These findings provide new information on how culturing islets prior to transplantation may be beneficial to their survival by allowing for autocrine activation of the pro-survival Akt pathway.

Morphogenetic plasticity of adult human pancreatic islets of Langerhans

The aim of this study was to investigate the phenotypic plasticity of pancreatic islets of Langerhans. Quiescent adult human islets were induced to undergo a phenotypic switch to highly proliferative duct-like structures in a process characterized by a loss of expression of islet-specific hormones and transcription factors as well as a temporally related rise in the expression of markers of both duct epithelial and progenitor cells. Short-term treatment of these primitive duct-like structures with the neogenic factor islet neogenesis-associated protein (INGAP104-118) induced their reconversion back to islet-like structures in a PI3-kinase-dependent manner. These neoislets resembled freshly isolated human islets with respect to the presence and topological arrangement of the four endocrine cell types, islet gene expression and hormone production, insulin content and glucose-responsive insulin secretion. Our results suggest that adult human islets possess a remarkable degree of morphogenetic plasticity. This novel observation may have important implications for understanding pancreatic carcinogenesis and islet neogenesis.

A genetic linkage map of willow ( Salix viminalis) based on AFLP and microsatellite markers

The genus Salix (willow) contains a number of species of great value as biomass crops. Efforts to breed varieties with improved biomass yields and resistances to pests and diseases are limited by the lack of knowledge on the genetic basis of the traits. We have used AFLP and microsatellite markers to construct a genetic map of willow from a full-sib cross of the diploid species Salix viminalis (2n = 38). In accordance with a double pseudo-testcross approach, separate parental maps were constructed and merged to produce a consensus map comprising 291 AFLP and 39 willow microsatellite markers. Nineteen poplar microsatellites were also tested in willow. Five of these amplified loci, of which two were mapped. Linkage groups of the consensus map that could be identified in the parental maps are presented here and spanned 1,256.5 cM with an average interval between markers of 4.4 cM.

Characterization of the flanking regions of Zea mays microsatellites reveals a large number of useful sequence polymorphisms

Sequence characterization of the flanking regions of 52 sequence-tagged microsatellite loci and two gene fragments from 11 Zea mays inbred lines identified a total of 324 sequence polymorphisms. The sequence polymorphisms consisted of both single-nucleotide polymorphisms and insertions/deletions in a ratio of approximately two to one. The level of sequence variation within the flanking regions of microsatellites linked to expressed sequence tags was lower than microsatellites that were unlinked to expressed sequence tags. However, both types of microsatellites generated a similar number of sequence-based alleles across the 11 genotypes surveyed. In two out of 20 microsatellites examined in detail, evidence was found for size-based allele homoplasy. Conversion of the observed sequence polymorphisms into allele-specific oligonucleotides followed by covalent binding to glass slides allowed the sequence polymorphisms to be used in a simple hybridization-based genotyping procedure. This procedure enabled us to discriminate between different inbred lines and allowed variations within a single inbred to be identified. The sequence information presented in this report could be used as a starting point for other programmes in the further development of a non-gel based, multi-locus, multi-allele screen for large-scale maize genotyping.

Evaluation of a PCR/DNA probe colorimetric membrane assay for identification of Campylobacter spp. in human stool specimens

DNA was extracted from 50 human stool specimens using the QIAamp DNA stool minikit. PCR amplification was followed by post-PCR hybridization to DNA probes specific for the Campylobacter genus, Campylobacter jejuni, and Campylobacter coli in a colorimetric membrane assay. Thirty-two of 38 culture-positive specimens were PCR/DNA probe positive for C. jejuni. The assay is rapid and simple and can be applied to stool specimens for the detection of Campylobacter.

Gene structure and promoter function of a teleost ribosomal protein: a tilapia (Oreochromis mossambicus) L18 gene

We have cloned and characterized a tilapia (Oreochromis mossambicus) L18 ribosomal protein gene, including the complete transcribed region and 488 bp of upstream regulatory sequences. We have also isolated two L18 cDNAs from another tilapia (Oreochromis niloticus) with a few conservative nucleotide differences. Our results suggest the presence of two genes in both species. Reporter constructs were tested for transient expression in CV1 cells and in microinjected zebrafish and tilapia embryos. The tilapia L18 promoter was able to drive expression of the reporter gene in all three experiments, with no apparent preference for a particular tissue. The tilapia L18 promoter is therefore likely to be a powerful tool to drive tissue-independent gene expression in fish.

Identification of transposon-tagged genes by the random sequencing of Mutator-tagged DNA fragments from Zea mays

We have used a universal adaptor amplification procedure to isolate random Mutator-tagged fragments from Mutator-active maize plants. Direct sequence characterization of 761 Mutator-tagged fragments indicated that a significant number were homologous to sequences within the public databases. The ability of Mutator-tagged fragments to detect homology was not related to the length of the sequence within the range 100-400 bp. However, fragments above this size did show an increased chance of detecting homology to either expressed sequence tags or genes. Characterization of the insertion sites of the Mutator elements suggested that while it does target transcribed regions, Mutator does not appear to have any site preference within the transcription unit. Hybridization of previously unidentified Mutator-tagged fragments to arrayed cDNA libraries confirmed that many of these also showed homology to transcribed regions of the genome. Examination of back-crossed progeny confirmed that all the insertions examined were germinal; however, in all but one case, selfing five individual Mutator-tagged lines failed to reveal an obvious phenotype. This study suggests that the random sequencing of Mutator-tagged fragments is capable of producing both a significant number of interesting transposon tagged genes and mutant plant lines, all of which could be extremely valuable in future gene discovery and functional genomics programmes.

Isolation and functional analysis of the histone H3 promoter from atlantic salmon (Salmo salar L.)

The histone H3 (sH3) promoter of Atlantic salmon (Salmo salar) was cloned via polymerase chain reaction using primers designed from the rainbow trout (Oncorhynchus mykiss) promoter sequence. A comparison of the nucleotide sequence with the equivalent sequences from rainbow trout and sockeye salmon (Oncorhynchus nerka) revealed a high degree of conservation. In vivo expression analysis of the sH3 promoter was carried out in both rainbow trout and zebrafish (Danio rerio) embryos. A direct comparison of the sH3 promoter with the viral RSV promoter in rainbow trout resulted in stronger expression of the sH3 promoter. Furthermore, lacZ expression directed by the sH3 promoter was ubiquitous in several different cell types in developing zebrafish embryos. These results suggest that the sH3 promoter will be useful in transgenic studies in Atlantic salmon.

Differentiation of desquamative interstitial pneumonia (DIP) from pulmonary adenocarcinoma by immunocytochemistry

AIM

After a misdiagnosis of pulmonary adenocarcinoma as desquamative interstitial pneumonia (DIP), we investigated whether immunohistochemical markers could differentiate these conditions.

METHODS AND RESULTS

Three cases of DIP and one pulmonary adenocarcinoma masquerading as DIP were studied by light and electron microscopy. All cases were mucin-negative. The cases of DIP were CD68 positive but cytokeratin-negative. The adenocarcinoma was cytokeratin-positive (AE1/3 and CAM5.2), as well as showing some CD68-positive cells. Markers for carcinoma (CEA, Ber-EP4, and Leu M1) were negative in all cases. Ultrastructurally the adenocarcinoma appeared to be derived from Type II pneumocytes.

CONCLUSION

Before a diagnosis of DIP is made, cytokeratin markers should be used.

Oral transmucosal fentanyl citrate as an additional premedicant for adult cardiac surgery patients

OBJECTIVE

To investigate the efficacy of a combination of midazolam and oral transmucosal fentanyl citrate (OTFC) as a preoperative medication for adult cardiac surgery patients compared with the use of midazolam alone.

DESIGN

A randomized, prospective study.

SETTING

University teaching hospital.

PARTICIPANTS

Patients scheduled for elective coronary artery bypass surgery.

INTERVENTIONS

All patients were given 50 micrograms/kg of midazolam intramuscularly in their rooms. Group I received 300 micrograms of OTFC Oralet (Anesta Corp, Salt Lake City, UT) if they weighed less than 70 kg and 400 micrograms of OTFC Oralet if they weighed more than 70 kg. Group II received a placebo Oralet. A radial artery catheter, two internal jugular venous catheters, and a pulmonary artery catheter inserted through one of the internal jugular catheters were placed in each study patient. Fentanyl was administered intravenously as a rescue drug.

MEASUREMENTS AND MAIN RESULTS

Ninety percent of midazolam/OTFC patients reported feeling no pain during catheter placement, compared with 50% of midazolam/placebo patients. Fifty percent of the placebo group required fentanyl supplement of 50 micrograms intravenously because of complaints of pain, compared with 10% of the OTFC group. The midazolam/OTFC group scored approximately 20% better than the placebo group in the independent observer score of patient analgesia and the anesthesiologist rating for ease of invasive catheter placement. No myocardial ischemic events were noted in either group as determined by electrocardiogram. All patients found the Oralet mode of delivery very acceptable.

CONCLUSIONS

The OTFC Oralet provides effective analgesia and sedation when combined with midazolam for invasive catheter placement in adult cardiac surgery patients. The OTFC Oralet with its gradual onset lessens the possibility of overmedicating with fentanyl, and it offers a very acceptable mode of delivery for a preemptive analgesic.

Chemotherapy with vincristine/ifosfamide/carboplatin/etoposide in small cell lung cancer

Although chemotherapy is considered the cornerstone of treatment for small cell lung cancer (SCLC), the majority of SCLC patients relapse and die of their disease within 2 years of diagnosis. Until newer, more effective drugs are developed, both optimization of available chemotherapeutic regimens and the use of combined chemotherapy/radiotherapy will be required to improve the survival of SCLC patients. Combining ifosfamide, carboplatin, and etoposide, among the most active single agents against SCLC, into the ICE regimen was a logical move that has resulted in improved response and survival rates. In limited and extensive SCLC, respectively, ICE and ICE administered with vincristine (VICE) have achieved overall response rates of 79% to 94% and 77% to 100% and 2-year survival rates of 24% to 33% and 9% to 25%, respectively. Treatment-related toxicities, especially myelosuppression, have hindered efforts to accelerate the administration of ICE and VICE regimens and to incorporate them into combined-modality treatments. However, the use of hematologic support measures, including growth factors and peripheral blood progenitor cells, may pave the way for maximizing the effectiveness of these regimens.

Sequence analysis and evolutionary aspects of piscine alpha-1-microglobulin/bikunin mRNA transcripts

Studies on mammalian alpha-1-microglobulin/bikunin (AMBP) protein sequences suggest the ancestral AMBP gene arose between 270 and 80 million years ago. Here we report a similar study including recently reported piscine AMBP messenger RNA sequences. The analysis implies a far earlier data for the assembly of the ancestral AMBP gene, more than 450 million years ago. Similarly, a revised date for the origin of the ancestral Kunitz-type protein is estimated at approximately 875 million years ago. Evolutionary conservation is apparent among all the AMBP amino acid sequences. This implies a common functional significance in both teleosts and mammals. However, an unusually rapid rate of evolution is observed for domain II of the piscine bikunin sequences, suggesting that this domain is no longer truly orthologous in fish.

Sequence of a cDNA clone encoding the Atlantic salmon alpha 1-microglobulin/bikunin protein

We report here the nucleotide sequence of a cDNA clone encoding the salmon (Salmo salar) alpha 1-microglobulin/bikunin precursor protein (sAMBP). The encoded precursor shows 36 and 42% amino acid (aa) similarity to the AMBP of pig and human, respectively. Signature aa motifs are conserved. The data infer that the ancestral AMBP gene arose more than 450 million years ago, before the tetrapod-fish divergence.

Cloning, genetic mapping, and expression analysis of an Arabidopsis thaliana gene that encodes 1-aminocyclopropane-1-carboxylate synthase

A genomic clone of one member of the Arabidopsis thaliana (L.) Heynh. 1-aminocyclopropane-1-carboxylate (ACC) synthase (S-adenosyl-L-methionine methylthioadenosine-lyase, EC 4.4.1.14) gene family (AT-ACC1) was isolated and sequenced. A region of homology was found in the 5'-untranslated region with the promoter of a zucchini and a tomato ACC synthase gene. Comparison of its primary structure with other ACC synthases revealed conservation of seven peptide regions as well as similarity with 11 amino acids of the catalytic site of aminotransferases. Genomic DNA gel blotting suggested the existence of an ACC synthase multigene family in Arabidopsis, possibly with three other members, none of which is very closely related to AT-ACC1. The existence of at least one other gene was confirmed by the isolation of a cDNA (AT-ACC2) from a flower-specific cDNA library. The AT-ACC1 gene was mapped on the Arabidopsis restriction fragment length polymorphism map and is located on the top of chromosome 1. This position does not correspond to any known mutation on the genetic map. Expression of the AT-ACC1 gene was studied by reverse transcription-PCR on total RNA. Messenger accumulation was strong in young leaves and flowers. The gene was not induced by wounding of young leaves or in seedlings in the presence of auxin. Ethylene exposure of mature plants led to an induction of AT-ACC1 gene expression. It is suggested that AT-ACC1 protein has a role in developmental control of ethylene synthesis.

Effects of ionizing radiation on a plant genome: analysis of two Arabidopsis transparent testa mutations

Ionizing radiation is known to cause chromosomal alterations such as inversions and deletions and has been used extensively for inducing mutations. In Arabidopsis, two methods for the isolation of genes identified on the basis of mutant phenotypes--genomic subtraction and chromosome walking--either rely on or are greatly facilitated by the availability of these types of mutations. This article gives a detailed characterization of ionizing radiation-induced mutations in plants. The Arabidopsis genes encoding chalcone flavanone isomerase (CHI) and dihydroflavonol 4-reductase (DFR) were cloned and found to correspond to two transparent testa loci. A CHI allele, generated by fast-neutron irradiation, consisted of an inversion within the gene. A 272-bp fragment from 38 centimorgans away on the same chromosome was transferred to one end of this inversion. A DFR allele, induced by x-irradiation, contained two deletions and an inversion of the 2.8-centimorgan intervening region. Sequence analysis of the break points in both mutants indicate that repair of radiation-induced damage involves mechanisms similar or identical to those that mediate the integration of foreign sequences into the genome. The chromosome rearrangements found in these mutants have important implications for the use of ionizing radiation-induced alleles in classical and molecular genetic experiments in plants.

Effects of ionizing radiation on a plant genome: analysis of two Arabidopsis transparent testa mutations

Ionizing radiation is known to cause chromosomal alterations such as inversions and deletions and has been used extensively for inducing mutations. In Arabidopsis, two methods for the isolation of genes identified on the basis of mutant phenotypes--genomic subtraction and chromosome walking--either rely on or are greatly facilitated by the availability of these types of mutations. This article gives a detailed characterization of ionizing radiation-induced mutations in plants. The Arabidopsis genes encoding chalcone flavanone isomerase (CHI) and dihydroflavonol 4-reductase (DFR) were cloned and found to correspond to two transparent testa loci. A CHI allele, generated by fast-neutron irradiation, consisted of an inversion within the gene. A 272-bp fragment from 38 centimorgans away on the same chromosome was transferred to one end of this inversion. A DFR allele, induced by x-irradiation, contained two deletions and an inversion of the 2.8-centimorgan intervening region. Sequence analysis of the break points in both mutants indicate that repair of radiation-induced damage involves mechanisms similar or identical to those that mediate the integration of foreign sequences into the genome. The chromosome rearrangements found in these mutants have important implications for the use of ionizing radiation-induced alleles in classical and molecular genetic experiments in plants.

Bioavailability in rats of human recombinant tissue plasminogen activator after subcutaneous and intramuscular injection

The bioavailability of human recombinant tissue plasminogen activator (rt-PA) in rats was measured after subcutaneous (s.c.) and intramuscular (i.m.) injection. Rt-PA was absorbed after both i.m. and s.c. injection, giving peak plasma concentrations within 30 min and 1 h, respectively, with detectable concentrations up to 6 h. These peak values of bioavailable t-PA were obtained in a functional fibrin plate assay of euglobulin precipitates and expressed as +88% and +243% (for s.c. and i.m. routes respectively) above basal rat fibrinolytic activity. Prior injection of rt-PA, s.c. or i.m., significantly reduced the weights of thrombi induced in the inferior vena cava after injection.

Sciatic neuropathy secondary to migration of trochanteric wire following total hip arthroplasty

Delayed sciatic neuropathy secondary to migration of a free segment of trochanteric wire in an otherwise successful total hip arthroplasty seems not to have been reported previously. A 60-year-old woman with a total hip arthroplasty with a lateral transtrochanteric approach had the trochanter reattached with two 18-gauge Vitallium wires. The osteotomy healed uneventfully despite a break in the vertical wire ten days after surgery. Five years and ten months later, the patient began to have severe sciatic pain. Roentgenograms showed a free fragment of trochanteric wire posterior to the hip joint. On exploration, the 2-cm wire fragment was found to lie entirely within the epineurium of the sciatic nerve.

Use of lacZ fusions to delimit regulatory elements of the inducible divergent GAL1-GAL10 promoter in Saccharomyces cerevisiae

We present the DNA sequence of a 914-base pair fragment from Saccharomyces cerevisiae that contains the GAL1-GAL10 divergent promoter, 140 base pairs of GAL10 coding sequence, and 87 base pairs of GAL1 coding sequence. From this fragment, we constructed four pairs of GAL1-lacZ and GAL10-lacZ fusions on various types of yeast plasmid vectors. On each type of vector, the fused genes were induced by galactose and repressed by glucose. The response of a GAL1-lacZ fusion to gal4 and gal80 regulatory mutations was similar to the response of intact chromosomal GAL1 and GAL10 genes. A set of deletions that removed various portions of the GAL10 regulatory sequences from a GAL10-CYC1-lacZ fusion was constructed in vitro. These deletions defined a relatively guanine-cytosine-rich region of 45 base pairs that contained sequences necessary for full-strength galactose induction and an adjacent guanine-cytosine rich 55 base pairs that contained sequences sufficient for weak induction.

Monoamine oxidase activity in diabetes

Monoamine oxidase (MAO) activities were measured in platelets from insulin-dependent and non-insulin-dependent diabetic subjects and in platelets from nondiabetic controls. Circulating levels of glycosylated hemoglobin (HbA1) were determined simultaneously. Mean MAO activities were not significantly different in any of these groups. MAO activity did not relate to the age of the individual, but mean values for females were higher than mean values for males in healthy controls and in insulin-dependent diabetics. In this study mean HbA1 levels were higher in female than in male diabetics. There was no relationship between MAO activity and HbA, level when results for males and females were analyzed separately.