Walking in the shoes of caregivers of children with obesity: supporting caregivers in paediatric weight management

To incorporate the perspectives and experiences of family caregivers of children with obesity, the KidFit Health and Wellness Clinic, a paediatric weight management programme, embedded feedback opportunities into various stages of programme development. Caregivers were eligible to participate if their children had completed initial 4-week group-based pilot programming or were currently receiving treatment in 10 or 12 week group-based programming. Data were collected through feedback session discussions, audio-recorded, transcribed verbatim and analysed thematically. In total, 6 caregivers participated in the pilot group feedback session and 32 caregivers participated in the structured group feedback sessions. Caregivers reported that healthy lifestyle strategies first communicated by clinic staff to children during group sessions provided expert validation and reinforcement when discussing similar messages at home. Caregivers reported feeling isolated and blamed for causing their children's obesity and appreciated the supportive forum that group-based programming provided for sharing experiences. Since experiences of blame and isolation can burden caregivers of children with obesity, paediatric weight management programmes might consider including peer support opportunities and discussion forums for ongoing social support in addition to education about lifestyle change.

Evaluating the thermal damage resistance of graphene/carbon nanotube hybrid composite coatings

We study laser irradiation behavior of multiwalled carbon nanotubes (MWCNT) and chemically modified graphene (rGO)-composite spray coatings for use as a thermal absorber material for high-power laser calorimeters. Spray coatings on aluminum test coupon were exposed to increasing laser irradiance for extended exposure times to quantify their damage threshold and optical absorbance. The coatings, prepared at varying mass % of MWCNTs in rGO, demonstrated significantly higher damage threshold values at 2.5 kW laser power at 10.6 μm wavelength than carbon paint or MWCNTs alone. Electron microscopy and Raman spectroscopy of irradiated specimens show that the coating prepared at 50% CNT loading endure at least 2 kW x cm(-2) for 10 seconds without significant damage. The improved damage resistance is attributed to the unique structure of the composite in which the MWCNTs act as an efficient absorber of laser light while the much larger rGO sheets surrounding them, dissipate the heat over a wider area.

Synthesis of polymer-derived ceramic Si(B)CN-carbon nanotube composite by microwave-induced interfacial polarization

We demonstrate synthesis of a polymer-derived ceramic (PDC)-multiwall carbon nanotube (MWCNT) composite using microwave irradiation at 2.45 GHz. The process takes about 10 min of microwave irradiation for the polymer-to-ceramic conversion. The successful conversion of polymer coated carbon nanotubes to ceramic composite is chemically ascertained by Fourier transform-infrared and X-ray photoelectron spectroscopy and physically by thermogravimetric analysis and transmission electron microscopy characterization. Frequency dependent dielectric measurements in the S-Band (300 MHz to 3 GHz) were studied to quantify the extent of microwave-CNT interaction and the degree of selective heating available at the MWCNT-polymer interface. Experimentally obtained return loss of the incident microwaves in the specimen explains the reason for heat generation. The temperature-dependent permittivity of polar molecules further strengthens the argument of internal heat generation.

Contribution of r&d to economic growth in the United States

Technological change has certainly contributed in a very important way to economic growth in the United States. Although existing studies have not been able to estimate this contribution with great accuracy, they have certainly indicated that this contribution has been large. Moreover, although econometric studies of the relationship between R&D and productivity increase have been subject to many limitations, they provide reasonably persuasive evidence that R&D has an important effect on productivity increase in the industries and time periods that have been studied. Turning to the adequacy of the nation's investment in R&D, there is too little evidence to support a very confident judgment as to whether or not we are underinvesting in certain types of R&D. However, practically all of the studies addressed to this question seem to conclude, with varying degrees of confidence, that we may be underinvesting in particular types of R&D in the civilian sector of the economy, and the estimated marginal rates of return from certain types of civilian R&D seem very high. Additional research is badly needed to determine more adequately the relationship of R&D to economic growth. I have indicated a number of specific areas where work is needed.

DMET microarray technology for pharmacogenomics-based personalized medicine

Human genome sequence variation in the form of single nucleotide polymorphisms (SNPs) as well as more complex structural variation such as insertions, duplications, and deletions underlies each individual's response to drugs and thus the likelihood of experiencing an adverse drug reaction. The ongoing challenge of the field of pharmacogenetics is to further understand the relationship between genetic variation and differential drug responses, with the overarching goal being that this will lead to improvements in both the safety and efficacy of drugs. The Affymetrix DMET Plus Premier Pack (DMET stands for Drug Metabolizing Enzymes and Transporters) enables highly multiplexed genotyping of known polymorphisms in Absorption, Distribution, Metabolism, and Elimination (ADME)-related genes on a single array. The DMET Plus Panel interrogates markers in 225 genes that have documented functional significance in phase I and phase II drug metabolism enzymes as well as drug transporters. The power of the DMET Assay has previously been demonstrated with regard to several different drugs including warfarin and clopidogrel. In a research study using an earlier four-color version of the assay, it was demonstrated that warfarin dosing can be influenced by a cytochrome P450 (CYP) 4F2 variant. Additionally, the assay has been used to demonstrate that CYP2C19 variants with decreased enzyme activity led to lower levels of the active clopidogrel metabolite, resulting in a decreased inhibition of platelets and a higher rate of cardiovascular events when compared to noncarriers of the DNA variant. Thus, highly multiplexed SNP genotyping focused on ADME-related polymorphisms should enable research into development of safer drugs with greater efficacy.

Transplant reno-vascular stenoses associated with early erythropoietin use

BACKGROUND AND OBJECTIVES

This report describes an unusual presentation of severe hypertension (HTN) in a subset of pediatric kidney recipients treated with a steroid avoidance pediatric renal transplantation protocol. The HTN was secondary to atypical, reno-vascular abnormalities (RVA) of the transplanted vasculature, temporally associated with erythropoietin (EPO) use.

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

To investigate the clinical significance underlying this event, a retrospective clinical study of 100 pediatric renal transplants was undertaken (50 steroid-free and 50 matched steroid-based controls), with peripheral blood transcriptional analysis of four RVA patients and controls.

RESULTS

Regardless of a higher observed incidence of anemia (p < 0.001) and greater overall EPO usage in the first post-transplant year in steroid-free patients, the incidence of new-onset HTN at one yr was significantly less in the steroid-free cohort (p = 0.03). Nevertheless, early EPO (first week post-transplant) was significantly associated with the combinatory findings of new-onset HTN (p = 0.03) and RVA (p = 0.007). Molecular mechanisms of RVA injury were investigated further by peripheral blood cDNA microarray gene expression profiling. A panel of 42 transcripts differentiated patients with RVA and HTN from three sets of matched controls, with and without HTN and EPO use, with 100% concordance (p < 0.001). The biological processes governed by these significant genes suggest a role for EPO regulation of growth factor receptor ubiquitination as a putative mechanism for renal vascular injury.

CONCLUSION

This study cautions against the use early post-transplant use of EPO in immunosuppression regimens with steroid minimization/avoidance, which may have an increased incidence of post-transplant anemia.

Identification of a peripheral blood transcriptional biomarker panel associated with operational renal allograft tolerance

Long-term allograft survival generally requires lifelong immunosuppression (IS). Rarely, recipients display spontaneous "operational tolerance" with stable graft function in the absence of IS. The lack of biological markers of this phenomenon precludes identification of potentially tolerant patients in which IS could be tapered and hinders the development of new tolerance-inducing strategies. The objective of this study was to identify minimally invasive blood biomarkers for operational tolerance and use these biomarkers to determine the frequency of this state in immunosuppressed patients with stable graft function. Blood gene expression profiles from 75 renal-transplant patient cohorts (operational tolerance/acute and chronic rejection/stable graft function on IS) and 16 healthy individuals were analyzed. A subset of samples was used for microarray analysis where three-class comparison of the different groups of patients identified a "tolerant footprint" of 49 genes. These biomarkers were applied for prediction of operational tolerance by microarray and real-time PCR in independent test groups. Thirty-three of 49 genes correctly segregated tolerance and chronic rejection phenotypes with 99% and 86% specificity. The signature is shared with 1 of 12 and 5 of 10 stable patients on triple IS and low-dose steroid monotherapy, respectively. The gene signature suggests a pattern of reduced costimulatory signaling, immune quiescence, apoptosis, and memory T cell responses. This study identifies in the blood of kidney recipients a set of genes associated with operational tolerance that may have utility as a minimally invasive monitoring tool for guiding IS titration. Further validation of this tool for safe IS minimization in prospective clinical trials is warranted.

Expression profiling of murine double-negative regulatory T cells suggest mechanisms for prolonged cardiac allograft survival

Recent studies have demonstrated that both mouse and human alpha beta TCR(+)CD3(+)NK1.1(-)CD4(-)CD8- double-negative regulatory T (DN Treg) cells can suppress Ag-specific immune responses mediated by CD8+ and CD4+ T cells. To identify molecules involved in DN Treg cell function, we generated a panel of murine DN Treg clones, which specifically kill activated syngeneic CD8+ T cells. Through serial cultivation of DN Treg clones, mutant clones arose that lost regulatory capacity in vitro and in vivo. Although all allogeneic cardiac grafts in animals preinfused with tolerant CD4/CD8 negative 12 DN Treg clones survived over 100 days, allograft survival is unchanged following infusion of mutant clones (19.5 +/- 11.1 days) compared with untreated controls (22.8 +/- 10.5 days; p < 0.001). Global gene expression differences between functional DN Treg cells and nonfunctional mutants were compared. We found 1099 differentially expressed genes (q < 0.025%), suggesting increased cell proliferation and survival, immune regulation, and chemotaxis, together with decreased expression of genes for Ag presentation, apoptosis, and protein phosphatases involved in signal transduction. Expression of 33 overexpressed and 24 underexpressed genes were confirmed using quantitative real-time PCR. Protein expression of several genes, including Fc epsilon RI gamma subunit and CXCR5, which are >50-fold higher, was also confirmed using FACS. These findings shed light on the mechanisms by which DN Treg cells down-regulate immune responses and prolong cardiac allograft survival.

Effects of BCL-2 overexpression on the sensitivity of MCF-7 breast cancer cells to ricin, diphtheria and Pseudomonas toxin and immunotoxins

Immunotoxins are presently being evaluated as novel agents for cancer therapy. The direct mechanism by which immunotoxins kill cancer cells is inhibition of protein synthesis, but cytotoxicity due to induction of apoptosis has also been observed with these agents. Some cancers that express high levels of BCL-2 are relatively resistant to apoptosis inducing agents. It is therefore important to determine to what degree the toxicity of ricin, diphtheria toxin, Pseudomonas exotoxin and Pseudomonas exotoxin derived immunotoxins towards cancer cells can be attributed to inhibition of protein synthesis, and to what degree to subsequent induction of apoptosis. We compared the sensitivity of MCF-7 breast cancer cells that were stably transfected with a BCL-2 expression plasmid and thus protected against apoptosis and of MCF-7 cells transfected with a control plasmid towards ricin, diphtheria and Pseudomonas toxin, a Pseudomonas toxin-derived immunotoxin (LMB-7) and tumour necrosis factor alpha (TNF). We found that BCL-2 mediated inhibition of apoptosis renders the cells almost completely resistant (1000-fold) to tumour necrosis factor, but the same cells were only 3-10 fold more resistant to cytotoxicity induced by immunotoxin LMB-7 as well as Pseudomonas exotoxin, diphtheria toxin and ricin. We next studied several leukaemia cell lines with variable levels of BCL-2 expression and found them quite sensitive to a Pseudomonas exotoxin containing immunotoxin independent of the level of BCL-2. Our data indicate that although BCL-2 overexpression can have a modest effect on sensitivity to an immunotoxin, cell lines derived from patients are still very sensitive to immunotoxins.

Applications of microarrays to renal transplantation: progress and possibilities

By rapidly generating global views of gene expression profiles, microarray technology offers a great advantage over traditional methods of studying gene expression. This technology is gaining rapid and widespread use in many areas of science and medicine because it can be easily adapted to study many experimental questions. This article will review the current applications of microarray technology in the field of renal transplantation, and discuss the potential impact of this technology on transplantation medicine.

The familial Mediterranean fever protein, pyrin, associates with microtubules and colocalizes with actin filaments

Familial Mediterranean fever (FMF) is a recessive disorder characterized by episodes of fever and intense inflammation. FMF attacks are unique in their sensitivity to the microtubule inhibitor colchicine, contrasted with their refractoriness to the anti-inflammatory effects of glucocorticoids. The FMF gene, MEFV, was recently identified by positional cloning; it is expressed at high levels in granulocytes and monocytes. The present study investigated the subcellular localization of the normal gene product, pyrin. These experiments did not support previously proposed nuclear or Golgi localizations. Instead fluorescence microscopy demonstrated colocalization of full-length GFP- and epitope-tagged pyrin with microtubules; this was markedly accentuated in paclitaxel-treated cells. Moreover, immunoblot analysis of precipitates of stabilized microtubules with recombinant pyrin demonstrated a direct interaction in vitro. Pyrin expression did not affect the stability of microtubules. Deletion constructs showed that the unique N-terminal domain of pyrin is necessary and sufficient for colocalization, whereas disease-associated mutations in the C-terminal B30.2 (rfp) domain did not disrupt this interaction. By phalloidin staining, a colocalization of pyrin with actin was also observed in perinuclear filaments and in peripheral lamellar ruffles. The proposal is made that pyrin regulates inflammatory responses at the level of leukocyte cytoskeletal organization and that the unique therapeutic effect of colchicine in FMF may be dependent on this interaction. (Blood. 2001;98:851-859)

The tumor-necrosis-factor receptor-associated periodic syndrome: new mutations in TNFRSF1A, ancestral origins, genotype-phenotype studies, and evidence for further genetic heterogeneity of periodic fevers

Mutations in the extracellular domain of the 55-kD tumor-necrosis factor (TNF) receptor (TNFRSF1A), a key regulator of inflammation, define a periodic-fever syndrome, TRAPS (TNF receptor-associated periodic syndrome [MIM 142680]), which is characterized by attacks of fever, sterile peritonitis, arthralgia, myalgia, skin rash, and/or conjunctivitis; some patients also develop systemic amyloidosis. Elsewhere we have described six disease-associated TNFRSF1A mutations, five of which disrupt extracellular cysteines involved in disulfide bonds; four other mutations have subsequently been reported. Among 150 additional patients with unexplained periodic fevers, we have identified four novel TNFRSF1A mutations (H22Y, C33G, S86P, and c.193-14 G-->A), one mutation (C30S) described by another group, and two substitutions (P46L and R92Q) present in approximately 1% of control chromosomes. The increased frequency of P46L and R92Q among patients with periodic fever, as well as functional studies of TNFRSF1A, argue that these are low-penetrance mutations rather than benign polymorphisms. The c.193-14 G-->A mutation creates a splice-acceptor site upstream of exon 3, resulting in a transcript encoding four additional extracellular amino acids. T50M and c.193-14 G-->A occur at CpG hotspots, and haplotype analysis is consistent with recurrent mutations at these sites. In contrast, although R92Q also arises at a CpG motif, we identified a common founder chromosome in unrelated individuals with this substitution. Genotype-phenotype studies identified, as carriers of cysteine mutations, 13 of 14 patients with TRAPS and amyloidosis and indicated a lower penetrance of TRAPS symptoms in individuals with noncysteine mutations. In two families with dominantly inherited disease and in 90 sporadic cases that presented with a compatible clinical history, we have not identified any TNFRSF1A mutation, despite comprehensive genomic sequencing of all of the exons, therefore suggesting further genetic heterogeneity of the periodic-fever syndromes.

Initial UK experience of the levonorgestrel-releasing contraceptive intravaginal ring

A study was performed to establish the tolerance, acceptability and associated efficacy of a levonorgestrel-releasing intravaginal ring (IVR) in a sample of British women requiring contraception. This was achieved with an open non-randomized prospective study of 1710 women aged 18-40 years, recruited in 75 centers geographically spread around the UK using an IVR designed to release 20 microg/day of levonorgestrel. Assessments were made at baseline, after 6 weeks, after 3 months and then 3-monthly. After initial insertion of the IVR, it was changed at 3-monthly intervals. A total of 1591 women were eligible for analysis, with 572 available after 12 months and 34 after 24 months of use. Life-table analysis revealed pregnancy rates of 5.1% and 6.5% at 12 months and 24 months, respectively. The IVR was rated as acceptable or very acceptable as a form of contraceptive by 60.7% of women at 12 months. The most common adverse events were menstrual disturbance, headache and vaginal discharge. No significant pattern of biochemical, hematological, microbiological or cytological abnormalities was found but vaginal erythematous lesions were noted at some centers. This IVR was found to be a generally well-accepted method of contraception with a failure rate comparable to some other progestogenonly methods. On this basis, further development of hormone-releasing intravaginal rings is justified.

Hydroxyapatite cranioplasty in fibrous dysplasia of the skull

We describe the case of a woman who had complained of worsening headache during the previous year. Analysis of computed tomography imaging and biopsy led to a diagnosis of fibrous dysplasia of the skull. A symptomatic frontal bone lesion was removed, and the resulting defect was repaired with hydroxyapatite cement. Hydroxyapatite cement has several advantages over hydroxyapatite ceramic blocks and granules, and it is particularly well suited for calvarial reconstruction.

The gene for familial Mediterranean fever, MEFV, is expressed in early leukocyte development and is regulated in response to inflammatory mediators

Familial Mediterranean fever (FMF) is a recessive disorder characterized by episodes of fever and neutrophil-mediated serosal inflammation. We recently identified the gene causing FMF, designated MEFV, and found it to be expressed in mature neutrophils, suggesting that it functions as an inflammatory regulator. To facilitate our understanding of the normal function of MEFV, we extended our previous studies. MEFV messenger RNA was detected by reverse transcriptase-polymerase chain reaction in bone marrow leukocytes, with differential expression observed among cells by in situ hybridization. CD34 hematopoietic stem-cell cultures induced toward the granulocytic lineage expressed MEFV at the myelocyte stage, concurrently with lineage commitment. The prepromyelocytic cell line HL60 expressed MEFV only at granulocytic and monocytic differentiation. MEFV was also expressed in the monocytic cell lines U937 and THP-1. Among peripheral blood leukocytes, MEFV expression was detected in neutrophils, eosinophils, and to varying degrees, monocytes. Consistent with the tissue specificity of expression, complete sequencing and analysis of upstream regulatory regions of MEFV revealed homology to myeloid-specific promoters and to more broadly expressed inflammatory promoter elements. In vitro stimulation of monocytes with the proinflammatory agents interferon (IFN) gamma, tumor necrosis factor, and lipopolysaccharide induced MEFV expression, whereas the antiinflammatory cytokines interleukin (IL) 4, IL-10, and transforming growth factor beta inhibited such expression. Induction by IFN-gamma occurred rapidly and was resistant to cycloheximide. IFN-alpha also induced MEFV expression. In granulocytes, MEFV was up-regulated by IFN-gamma and the combination of IFN-alpha and colchicine. These results refine understanding of MEFV by placing the gene in the myelomonocytic-specific proinflammatory pathway and identifying it as an IFN-gamma immediate early gene.

Diet and waist-to-hip ratio: important predictors of lipoprotein levels in sedentary and active young men with no evidence of cardiovascular disease

OBJECTIVE

Healthy, young men were studied to determine the relationship of energy and nutrient intake and physical activity to concentrations of plasma lipoprotein and cholesteryl ester transfer protein.

DESIGN

A cross-sectional study compared active and sedentary male subjects (17 to 35 years old) with no personal or family history of coronary heart disease. Participants kept 20-day food and activity journals. Individual intakes of energy, protein, carbohydrate, fat, saturated fat, monounsaturated fatty acids, polyunsaturated fatty acids, dietary fiber, and alcohol were evaluated. Measurements of blood lipids (total cholesterol and triglycerides, high- and low-density lipoprotein cholesterol); apolipoproteins; cholesteryl ester transfer protein; anthropometric variables (body mass index, waist-to-hip ratio, percentage of body fat); and aerobic capacity were taken during fall and spring data collection periods. SUBJECT SELECTION: Subjects were selected on the basis of normal blood lipid levels, absence of underlying disease, and willingness to comply with their current level of physical activity for the duration of the study. Minimal sample size for statistical power was 12 men per group: 12 of 15 subjects who exercised and 13 of 15 subjects who were sedentary completed all phases of the study.

STATISTICAL ANALYSES

Statistical analyses consisted of 2-way analysis of variance (activity level and season). Pearson product moment correlations and multiple regression analyses were conducted to assess whether energy and nutrient intakes, physical activity status, and/or anthropometric variables predicted plasma concentrations of lipids and apolipoproteins.

RESULTS

Lower waist-to-hip ratio, and not specifically activity level, was associated with higher levels of high-density lipoprotein cholesterol (HDL-C) and lower levels of low-density lipoprotein cholesterol (LDL-C). Dietary intake of saturated and monounsaturated fats and alcohol predicted changes in some apolipoprotein and lipoprotein levels.

APPLICATIONS

Use of waist-to-hip ratio in the primary prevention of coronary heart disease is a simple and cost-effective measure to predict development of abnormal lipoprotein profiles in young men. Specific dietary recommendations include adoption of a heart-healthy diet with emphasis on monounsaturated fatty acids (10% to 12% of energy or one third of total fat intake) and the suggestion that small amounts of alcohol (< 3 drinks per week) may, indeed, be beneficial. Because alcohol and waist-to-hip ratio were both important predictors of LDL-C level, even in active young men, the consumption of low levels of alcohol may be beneficial only if waist-to-hip ratio is maintained within the healthful range by achieving an appropriate balance of physical activity and macronutrient intake.

Germline mutations in the extracellular domains of the 55 kDa TNF receptor, TNFR1, define a family of dominantly inherited autoinflammatory syndromes

Autosomal dominant periodic fever syndromes are characterized by unexplained episodes of fever and severe localized inflammation. In seven affected families, we found six different missense mutations of the 55 kDa tumor necrosis factor receptor (TNFR1), five of which disrupt conserved extracellular disulfide bonds. Soluble plasma TNFR1 levels in patients were approximately half normal. Leukocytes bearing a C52F mutation showed increased membrane TNFR1 and reduced receptor cleavage following stimulation. We propose that the autoinflammatory phenotype results from impaired downregulation of membrane TNFR1 and diminished shedding of potentially antagonistic soluble receptor. TNFR1-associated periodic syndromes (TRAPS) establish an important class of mutations in TNF receptors. Detailed analysis of one such mutation suggests impaired cytokine receptor clearance as a novel mechanism of disease.

Parallel molecular genetic analysis

We describe recent progress in parallel molecular genetic analyses using DNA microarrays, gel-based systems, and capillary electrophoresis and utilization of these approaches in a variety of molecular biology assays. These applications include use of polymorphic markers for mapping of genes and disease-associated loci and carrier detection for genetic diseases. Application of these technologies in molecular diagnostics as well as fluorescent technologies in DNA analysis using immobilized oligonucleotide arrays on silicon or glass microchips are discussed. The array-based assays include sequencing by hybridization, cDNA expression profiling, comparative genome hybridization and genetic linkage analysis. Developments in non microarray-based, parallel analyses of mutations and gene expression profiles are reviewed. The promise of and recent progress in capillary array electrophoresis for parallel DNA sequence analysis and genotyping is summarized. Finally, a framework for decision making in selecting available technology options for specific molecular genetic analyses is presented.

Connexin-26 mutations in sporadic and inherited sensorineural deafness

BACKGROUND

Hearing impairment affects one infant in 1000 and 4% of people aged younger than 45 years. Congenital deafness is inherited or apparently sporadic. We have shown previously that DFNB1 on chromosome 13 is a major locus for recessive deafness in about 80% of Mediterranean families and that the connexin-26 gene gap junction protein beta2 (GJB2) is mutated in DFNB1 families. We investigated mutations in the GJB2 gene in familial and sporadic cases of deafness.

METHODS

We obtained DNA samples from 82 families from Italy and Spain with recessive non-syndromic deafness and from 54 unrelated participants with apparently sporadic congenital deafness. We analysed the coding region of the GJB2 gene for mutations. We also tested 280 unrelated people from the general populations of Italy and Spain for the frameshift mutation 35delG.

FINDINGS

49% of participants with recessive deafness and 37% of sporadic cases had mutations in the GJB2 gene. The 35delG mutation accounted for 85% of GJB2 mutations, six other mutations accounted for 6% of alleles, and no changes in the coding region of GJB2 were detected in 9% of DFNB1 alleles. The carrier frequency of mutation 35delG among people from the general population was one in 31 (95% CI one in 19 to one in 87).

INTERPRETATION

Mutations in the GJB2 gene are a major cause of inherited and apparently sporadic congenital deafness. Mutation 35delG is the most common mutation for sensorineural deafness. Identification of 35delG and other mutations in the GJB2 gene should facilitate diagnosis and counselling for the most common genetic form of deafness.

Recombinant RFB4 immunotoxins exhibit potent cytotoxic activity for CD22-bearing cells and tumors

Many B-cell malignancies express the CD22 antigen on their cell surface. To kill cells expressing this antigen, the RFB4 monoclonal antibody (MoAb) has been linked chemically with either deglycosylated ricin A chain or truncated versions of Pseudomonas exotoxin. These immunotoxins exhibited selective cytotoxic activity for CD22+ cells and antitumor activity in nude mouse models bearing human B-cell lymphomas. To construct a recombinant immunotoxin targeted to CD22, we first cloned the variable portions of the heavy and light chains of RFB4. The cloned Fv fragments were joined by a newly created disulfide bond to form a disulfide stabilized (ds) construct. The RFB4 construct was combined by gene fusion with PE38, a truncated version of PE. The recombinant immunotoxin was then expressed in Escherichia coli, purified by column chromatography and tested for cytotoxicity activity. RFB4(dsFv)PE38 retained its binding activity for CD22, was very stable at 37 degrees C and exhibited selective cytotoxic activity for CD22+-cultured cell lines. Because of its favorable binding characteristics and potency for CD22-positive cell lines, RFB4(dsFv)PE38 was tested for antitumor activity in a nude mouse model of human lymphoma. CA46 cells were injected subcutaneously and then treated with the RFB4(dsFv)PE38 immunotoxin. Antitumor activity was dose responsive and was not evident when an irrelevant immunotoxin was administered on the same schedule.

Connexin26 mutations associated with the most common form of non-syndromic neurosensory autosomal recessive deafness (DFNB1) in Mediterraneans

Non-syndromic neurosensory autosomal recessive deafness (NSRD) is the most common form of genetic hearing loss. Previous studies defined at least 15 human NSRD loci. Recently we demonstrated that DFNB1, located on the long arm of chromosome 13, accounts for approximately 80% of cases in the Mediterranean area. Further analysis with additional markers now identifies several recombinants which narrow the candidate region to approximately 5 cM, encompassed by markers D13S141 and D13S232 and including several ESTs and candidate genes, including the connexin26 (GJB2) gene. Analysis of PCR products from our affected patients' DNA shows two frameshift mutations in the connexin26 gene. Deletion of a G within a stretch of six Gs at position 35 of the GJB2 cDNA (mutation 35delG) leads to premature chain termination and is present in 63% of NSRD chromosomes, demonstrating linkage to chromosome 13. Deletion of a T at position 167 of GJB2 (mutation 167delT), also resulting in premature chain termination, was detected in another patient. Four neutral sequence polymorphisms were also identified. These findings are in agreement with a recent study showing that mutations in the connexin26 gene are associated with genetic forms of deafness in three Pakistani families and that GJB2 is DFNB1. Connexin26 is a member of a large family of proteins involved in formation of gap junctions, which are involved in electrical synapses and the direct transfer of small molecules and ionic currents between neighboring cells. The identification of GJB2 as the DFNB1 gene should provide a better understanding of the biology of normal and abnormal hearing, help form the basis for diagnosis and may facilitate development of strategies for treatment of this common genetic disorder.

Fluorescence imaging in human identity testing

We have investigated the use of fluorescence detection and the FluorImager S1 System (Molecular Dynamics) for analyzing a comprehensive set of human DNA typing tests. We used an alkaline phosphatase-conjugated YNH24 oligonucleotide probe to the repeat-containing D2S44 locus to detect both alleles in 50 ng of human genomic DNA (0.025 amol) by Southern hybridization using a chemifluorescent substrate. We used a similar approach to quantify human DNA using an enzyme-conjugated oligonucleotide probe to the D17Z1 locus. Both fluorescent nucleic acid gel staining and direct fluorescent labeling methods were tested to detect PCR-based D1S80 and short tandem repeat (STR) multiplex allele profiles. The fluorescent staining method sensitively detected these allelic profiles in both denaturing and non-denaturing acrylamide gels using a simple, 10-min procedure. Fluorescent primers eliminate the doublet band patterns often seen with staining methods, which label both strands of the amplified products. This complicates interpretation of STR typing tests. Only one primer for each locus is labeled, so only one strand of the DNA product is detected. Fluorescein end-labeled primers were used in multiplex PCR to amplify, detect and type STRs.

Characterization of RFB4-Pseudomonas exotoxin A immunotoxins targeted to CD22 on B-cell malignancies

To develop an immunotoxin for the treatment of B-cell malignancies, we constructed several candidate conjugates with RFB4, a B-cell specific anti-CD22 IgG1, and truncated forms of Pseudomonas exotoxin (PE). The four versions of PE included PE35 and PE35KDEL, which were linked to RFB4 via a disulfide bond, and PE38 and PE38KDEL, which were linked via a thioether bond. The PE35 truncated forms, which are fully active in ADP ribosylation and lack receptor binding sequences, do not require intracellular proteolytic cleavage in order to be active. PE35KDEL has the consensus endoplasmic reticulum retention signal, KDEL, replacing the wild type PE C-terminal sequence, REDLK. The PE38 forms retain all of domain II and therefore require cleavage to be active within cells. Cytotoxicity experiments on CD22-positive cell lines revealed that the PE35 conjugates were more active than the PE38 versions and the presence of the KDEL sequence generally enhanced toxicity by 5-10-fold compared to that of REDLK. The RFB4-PE35KDEL immunotoxin was most active in cytotoxicity assays against Burkitt's lymphoma cell lines such as Daudi and CA46 (IC50 = 0.2 ng/mL) and displayed little cytotoxicity toward human vascular endothelial cells (IC50 > 20 micrograms/mL). Results of experiments conducted in nude mice showed that both RFB4-PE35KDEL and RFB4-PE35 could inhibit the development of subcutaneous CA46 tumors.

Infundibulopelvic stenosis, multicystic kidney, and calyectasis in a kindred: clinical observations and genetic analysis

Congenital obstructive anomalies of the urinary tract usually occur sporadically. We describe inheritance in a three-generation kindred of a spectrum of kidney anomalies consistent with an autosomal-dominant mode of transmission, with incomplete penetrance, calyectasis (maternal grandmother), infundibulopelvic stenosis (uncle), and multicystic kidney (male proband, age 4 years). The proband's mother, father and half sister had normal renal imaging studies. Inheritance of informative polymorphic markers (3'-HVR, GGG1, GGG9, SM-7, KG8, and CW3) mapping close to the adult polycystic kidney disease type 1 (PKD-1) and tuberous sclerosis (TSC-2) loci on chromosome 16p was evaluated by Southern blot studies and by PCR-based, fluorescent genotyping for linkage to phenotype. The 3 affected individuals, as well as the unaffected mother (obligate carrier) and unaffected half-sister, inherit a common chromosome haplotype linked to the PKD1 locus. Our findings support the hypothesis that these anomalies may be part of a spectrum of obstructive renal dysplasia which are inherited as a simple Mendelian trait exhibiting an autosomal-dominant mode of transmission with variable expression and incomplete penetrance.

Genetic and molecular analysis of hyperplastic discs, a gene whose product is required for regulation of cell proliferation in Drosophila melanogaster imaginal discs and germ cells

The hyperplastic discs (hyd) gene (formerly called l(3)c43) is located at 85E1-10 on the third chromosome of Drosophila melanogaster. It was originally identified by a temperature-sensitive mutation that causes imaginal disc overgrowth in mutant larvae raised at a restrictive temperature. Twenty new alleles of hyperplastic discs have been recovered in gamma ray, ethyl methanesulfonate and hybrid dysgenesis screens, and the molecular lesions have been identified for several of the alleles. The null phenotype appears to be lethality at or before the second instar. Adults that can be obtained in crosses of temperature-sensitive alleles maintained at permissive temperatures are sterile with one exception and have defects in germ tissue morphology. The hyperplastic discs locus has been cloned by chromosome walking from the alpha-tubulin-2 gene and encodes a 9.5-kb messenger RNA, containing a 2897-amino-acid open reading frame. Sequence analysis of HYD reveals strong similarity to a portion of the C-terminus of poly(A) binding protein and to the RAT 100-kDa PROTEIN, whose function is unknown. Developmental Northern and Western analyses show coincident accumulation of the 9.5-kb transcript and the 280-kDa protein at all stages of development, with high levels at the embryonic and pupal stages. The 280-kDa HYD protein accumulates at decreased levels in mutant alleles and at restrictive temperatures in ts alleles. Examination of relative levels of HYD protein in mutant animals support the idea that less severe mutations are those that result in disc overgrowth, while more severe mutations result in variable disc growth phenotypes.

Interaction of rare illegitimate recombination event and a poly A addition site mutation resulting in a severe form of alpha thalassemia

The clinical diversity of thalassemia depends on interaction of diverse genetic defects. We have characterized a severe form of alpha thalassemia caused by coinheritance of a rare alpha-globin gene deletion and a nondeletional defect in a southern Italian family. The proband, a 7-year-old girl, exhibited an abnormal hemoglobin electrophoresis pattern with hemoglobin H and hemoglobin Barts, indicating inheritance of H and hemoglobin Barts, indicating inheritance of a severe form of alpha thalassemia. Southern blot analysis of DNA showed normal as well as aberrant alpha-globin gene fragments indicating heterozygosity for a deletional form of alpha thalassemia in the proband and her mother. The coinheritance of a nondeletional form of alpha thalassemia (alpha alpha T) was suspected because of the severity of the proband's phenotype and the presence of normal alpha-globin gene fragments in the father. Selective polymerase chain reaction of the paternal alpha 1- and alpha 2-globin genes in the proband followed by DNA sequence analysis showed an AATAAA to AATGAA mutation in the polyadenylation signal sequence of the alpha 2-globin gene. Genomic DNA mapping and sequence analysis of a unique polymerase chain reaction product generated across the deletion breakpoint of the maternal allele showed a 5,201-bp deletion extending from 870 nucleotides 5' of the alpha 2-globin gene to nucleotide +519 in the alpha 1-globin gene. This deletion is similar to that previously suggested by blotting studies in a Greek family (Pressley et al, Nucleic Acids Res 8:4889, 1980) and removes the entire alpha 2-globin gene and a portion of the 5' end of the alpha 1-globin gene. Sequence characterization of the resultant aberrant truncated alpha 1-globin gene from the proband showed a 27 nucleotide duplication corresponding to the 3' end of the alpha-globin gene IVS-2 region separated by the insertion of a tetranucleotide (GGTT), suggesting that this deletion is caused by an illegitimate recombination event.

Prenatal diagnosis of Charcot-Marie-Tooth disease type 1A by multicolor in situ hybridization

Genetic heterogeneity within the most common genetic neuropathy, Charcot-Marie-Tooth disease (CMT) results in about 70% slow nerve conduction CMT1 and 30% normal nerve conduction CMT2. Autosomal dominant CMT1A on chromosome 17p11.2 represents about 70% of CMT1 cases and about 50% of all CMT cases. Three different size CMT1A duplications with variable flanking breakpoints were characterized by multicolor in situ hybridization and confirmed by pulsed field gel electrophoresis and quantitative polymerase chain reaction (PCR) amplification. These different size duplications result in the same CMT1A phenotype confirming that trisomy of a normal gene region results in CMT1A. The smallest duplication does not include the 409 locus used previously to screen for CMT1A duplications. Direct analysis of interphase nuclei from fetuses and at-risk patients by multicolor in situ hybridization to a commonly duplicated CMT1A probe is informative more often than polymorphic PCR analysis, faster than pulsed field gel electrophoresis (PFGE), and faster, more informative, and more reliable than restriction enzyme analysis. CMT1B restriction enzyme analysis of CMT pedigrees without CMT1A is expected to diagnose another 8% of at-risk CMT1 patients (total: 78%).

Industrial Innovation in Japan and the United States

Japanese firms tend to be quicker and more economical than U.S.firms at developing and introducing new products and processes, but this advantage seems to exist only among innovations based on external technology, rather than internal technology. Whereas U.S.firms put more emphasis on marketing start-up, they put much less emphasis on tooling, equipment, and manufacturing facilities than do Japanese firms. Applied R&D in Japan, which focuses more on processes than in the United States, seems to have yielded a handsome return; but there is no evidence that the rate of return from basic research has been relatively high in Japan. In robotics, the Japanese edge seems to increase as one moves from R&D toward the market.

Rapid searches for complex patterns in biological molecules

The intrinsic redundancy of genetic information makes searching for patterns in biological sequences a difficult task. We have designed an interactive self-documenting computer program called QUEST that allows rapid searching of large DNA and protein data banks for highly redundant consensus sequences or character patterns. QUEST uses a concise language for specifying character patterns containing several levels of ambiguity and pattern arrangement. Examples of the use of this program for sequence data are given. Details of the algorithm and pattern optimization are explained.

Comparison of Psychiatric-Mental Health Nursing Education Objectives: Consumers, Educators, and Practitioners

This consumer-nurse study was part of a larger project, Research in Mental Health Education, which compared the priorities of educators and practitioners within and between three core mental health professions and between the professionals and consumers. In the consumer-nurse portion of the study, the objectives for graduate education in psychiatric-mental health nursing were validated by psychiatric-mental health nursing educators (N=20) based in four university programs in the East, West, and Midwest. Another sample of nurse educators and practitioners in this specialty area, drawn from nine states, prioritized these objectives. A separate deck of objectives for mental health professionals was generated and prioritized by consumers (N=15) who were members of the Mental Health Association of Minnesota. Standardized procedures for generating and validating the objectives for nurses and consumers and the same task, the Priority Sort, were used by all subjects, nurses, and consumers, to prioritize the objectives. Similarities and differences between nurses and consumers are discussed. Differences between nurse educators and practitioners, which are statistically significant, also are described. Implications for consumer and practitioner input into curricular decisions are discussed as well as interdisciplinary courses that could conserve faculty time and budgetary resources.

Tax Policy and Innovation

Tax policy should be formulated with recognition of its effects on research and development and innovation. Many changes in tax policy designed to stimulate innovation have been proposed in recent years. Some of these changes were embodied in the 1981 tax bill. Basic economic analysis and rudimentary statistics enable economists to make some useful statements about the effects of recent and proposed tax changes but, because practically no studies have been conducted in this area, there is little or no dependable information concerning the quantitative impact of particular changes of this sort on the rate of innovation.

Research and Development, Productivity, and Inflation

R & D, through its effects on the rate of productivity increase, can significantly restrain the rate of inflation in the medium and long run. High rates of inflation damage the workings of the price system and impair the efficiency of practically all economic activities, including R & D. Findings suggest that the percentage increase between 1969 and 1979, in total real R & D expenditures, has been exaggerated due to the inadequacy of the gross national product deflator as applied to R & D.

A conceptual framework for psychiatric-mental health nursing

A conceptual framework for a psychiatric-mental health nursing program gives direction for course content and becomes a rich source of hypotheses leading to development of theory. For this described framework tenets of humanistic theorists provide the philosophical base: Belief in the individual's responsibility, capacity and potential for growth; meaning of life; respect and dignity of the individual; and freedom of the individual for self-determination. Four major components comprise the framework: social systems and developmental theories, communication concepts, and self-esteem. Set in the nursing process schema, concepts from social systems and developmental theories are used in the assessment, concepts from communication theories are the basis for intervention, and changes in self-esteem become a measure of evaluation. The framework is applicable for individual clients, families, and/or groups. The nurse therapist is viewed in the same framework which may evolve into an intersystem model. Numerous research questions are suggested which may validate the relationships between the components of the framework.