Guselkumab is superior to fumaric acid esters in patients with moderate-to-severe plaque psoriasis who are naive to systemic treatment: results from a randomized, active-comparator-controlled phase IIIb trial (POLARIS).

BACKGROUND: Guselkumab, a fully human interleukin-23 antibody, is approved for systemic treatment of patients with moderate-to-severe plaque psoriasis. OBJECTIVES: To compare the efficacy and safety of guselkumab with those of fumaric acid esters (FAE) in patients with moderate-to-severe plaque psoriasis who are naive to systemic treatment. METHODS: Eligible patients were randomized to this multicentre, randomized, open-label, assessor-blinded, active-comparator-controlled phase IIIb study to receive guselkumab 100 mg by subcutaneous injection or oral FAE according to local label guidelines. RESULTS: Through week 24, 56 of 60 patients completed guselkumab treatment and 36 of 59 completed FAE treatment. The primary endpoint (proportion of patients with ≥ 90% improvement from their baseline Psoriasis Area and Severity Index; PASI 90 response) was achieved by significantly more patients receiving guselkumab than FAE at week 24 (82% vs. 14%, P < 0·001). Analysis of the major secondary endpoints confirmed a statistically significant difference between the treatments with regards to PASI 75 response (90% vs. 27%, P < 0·001) and Dermatology Life Quality Index score of 0 or 1 (no effect at all on the patient's quality of life; 62% vs. 17%, P < 0·001). More patients in the guselkumab group achieved completely clear skin (PASI 100 response) than in the FAE group (32% vs. 3%, P < 0·001). The incidence of adverse events was lower with guselkumab than with FAE (73% vs. 98%). Overall, 28% of patients on FAE discontinued due to an adverse event, compared with none receiving guselkumab. No new safety findings were observed for guselkumab. CONCLUSIONS: Guselkumab demonstrated superiority over FAE in systemic-treatment-naive patients with moderate-to-severe plaque psoriasis through 24 weeks.

Multitarget Stool DNA Test Performance in an Average-Risk Colorectal Cancer Screening Population.

INTRODUCTION: We set out to evaluate the performance of a multitarget stool DNA (MT-sDNA) in an average-risk colonoscopy-controlled colorectal cancer (CRC) screening population. MT-sDNA stool test results were evaluated against fecal immunochemical test (FIT) results for the detection of different lesions, including molecularly defined high-risk adenomas and several other tumor characteristics. METHODS: Whole stool samples (n = 1,047) were prospectively collected and subjected to an MT-sDNA test, which tests for KRAS mutations, NDRG4 and BMP3 promoter methylation, and hemoglobin. Results for detecting CRC (n = 7), advanced precancerous lesions (advanced adenoma [AA] and advanced serrated polyps; n = 119), and non-AAs (n = 191) were compared with those of FIT alone (thresholds of 50, 75, and 100 hemoglobin/mL). AAs with high risk of progression were defined by the presence of specific DNA copy number events as measured by low-pass whole genome sequencing. RESULTS: The MT-sDNA test was more sensitive than FIT alone in detecting advanced precancerous lesions (46% (55/119) vs 27% (32/119), respectively, P < 0.001). Specificities among individuals with nonadvanced or negative findings (controls) were 89% (791/888) and 93% (828/888) for MT-sDNA and FIT testing, respectively. A positive MT-sDNA test was associated with multiple lesions (P = 0.005), larger lesions (P = 0.03), and lesions with tubulovillous architecture (P = 0.04). The sensitivity of the MT-sDNA test or FIT in detecting individuals with high-risk AAs (n = 19) from individuals with low-risk AAs (n = 52) was not significantly different. DISCUSSION: In an average-risk screening population, the MT-sDNA test has an increased sensitivity for detecting advanced precancerous lesions compared with FIT alone. AAs with a high risk of progression were not detected with significantly higher sensitivity by MT-sDNA or FIT.

Social position and geriatric syndromes among Swedish older people: a population-based study.

BACKGROUND: Older people with a low social position are at higher risk of poor health outcomes compared to those with a higher social position. Whether lower social position also increases the risk of geriatric syndromes (GSs) remains to be determined. This study investigates the association of social position with GSs among older community-dwellers. METHODS: Three consecutive population-based health surveys in 2006, 2010 and 2014 among older community-dwellers (age 65-84 years) in Stockholm County were combined (n = 17,612) and linked with Swedish administrative registry information. Social position was assessed using registry information (i.e. education, country of origin and civil status) and by self-reports (i.e. type of housing and financial stress). GSs were assessed by self-reports of the following conditions: insomnia, urinary incontinence, functional decline, falls, depressive disorder, hearing or vision problems. Binomial logistic regression analyses were used to estimate the association between social position and GSs after adjusting for age, sex, health status, health behavior and social stress. RESULTS: The prevalence of GSs was 70.0%, but varied across GSs and ranged from 1.9% for depression to 39.1% for insomnia. Living in rented accommodation, being born outside the Nordic countries, being widowed or divorced were associated with GS presence. Financial stress was most strongly associated with GSs (adjusted odds ratio, 2.59; 95% CI, 2.13-3.15). CONCLUSION: GSs are highly prevalent among older Swedish community-dwellers with wide variations across syndromes and strong association with all measures of social position, most strikingly that of experiencing financial stress.

Injurious falls and subsequent adverse drug events among elderly - a Swedish population-based matched case-control study.

BACKGROUND: Fall injuries are stressful and painful and they have a range of serious consequences for older people. While there is some clinical evidence of unintentional poisoning by medication following a severe fall injuries, population-based studies on that association are lacking. This is investigated in the current study, in which attention is also paid to different clinical conditions of the injured patients. METHODS: We conducted a matched case-control study of Swedish residents 60 years and older from various Swedish population-based registers. Cases defined as adverse drug events (ADE) by unintentional poisoning leading to hospitalization or death were extracted from the National Patient Register (NPR) and the Cause of Death Register from January 2006 to December 2009 (n = 4418). To each case, four controls were matched by sex, age and residential area. Information on injurious falls leading to hospitalization six months prior to the date of hospital admission or death from ADE by unintentional poisoning, and corresponding date for the controls, was extracted from the NPR. Data on clinical conditions, such as dispensed medications, comorbidity and previous fall injuries were also extracted from the Swedish Prescribed Drug Register (SPDR) and NPR. Effect estimates were calculated using conditional logistic regression and presented as odds ratios (OR) and 95% confidence intervals (CI). RESULTS: We found a three-fold increased risk of unintentional poisoning by medication in the six-month period after an injurious fall (OR 3.03; 95% CI, 2.54-3.74), with the most pronounced increase 1-3 weeks immediately after (OR, 7.66; 95% CI, 4.86-12.1). In that time window, from among those hospitalized for a fall (n = 92), those who sustained an unintentional poisoning (n = 60) tended to be in poorer health condition and receive more prescribed medications than those who did not, although this was not statistically significant. Age stratified analyses revealed a higher risk of poisoning among the younger (aged 60-79 years) than older elderly (80+ years). CONCLUSION: Medication-related poisoning leading to hospitalization or death can be an ADE subsequent to an episode of hospitalization for a fall-related injury. Poisoning is more likely to occur closer to the injurious event and among the younger elderly. It cannot be ruled out that some of those falls are themselves ADE and early signs of greater vulnerability among certain patients.

Molecular profiling of longitudinally observed small colorectal polyps: A cohort study.

BACKGROUND: Knowledge of the natural history of colorectal adenomas is limited because these lesions are removed upon detection. The few studies in which small adenomas have been left in situ for a limited period of time, have shown that most lesions remain stable or even completely regress. Specific DNA copy number changes ('cancer associated events' or CAEs) are associated with progression of adenomas to cancer. In this study we evaluated whether molecular features of progression correlated with growth of small polyps. METHODS: Small (6-9 mm) colorectal precursor lesions detected on CT-colonography (CTC) were left in situ and re-evaluated with CTC after three years. Based on volumetric change, polyps were classified as either grown, stable or regressed. Surveillance CTC was followed by colonoscopy, during which all lesions were resected. Using DNA isolated from FFPE polyp tissues, low-coverage whole genome sequencing was performed to determine DNA copy number profiles, as well as target enrichment mutation analysis and CpG island methylation phenotype (CIMP) analysis. Expression of DNA mismatch repair (MMR) proteins was determined by immunohistochemistry. Samples were marked as MMR proficient if all MMR proteins were expressed. FINDINGS: Out of 68 polyps resected at colonoscopy, for 65 (96%) material was available. Of these, 31 (48%) had grown, 27 (41%) remained stable and 7 (11%) regressed. Polyps with at least one CAE had higher growth rates compared to polyps without CAEs (difference 91% growth (95% CI 13-169), p = .023). CAEs were absent in lesions that had partially regressed. Mutations occurred in 94% of the polyps, with higher growth rates being associated with polyps having ≥2 mutations compared to lesions with only 0-1 mutations (difference 99% growth (95% CI 9-189), p = .032). All samples were MMR proficient. No relation between growth and CIMP was observed. INTERPRETATION: Molecular alterations associated with colorectal cancer, correlated with growth of small polyps and were absent in polyps that regressed. Therefore, this longitudinal study provides in vivo support in the human setting for the functional role of these molecular alterations, that have mostly been identified by cross sectional observations in tissue samples of colorectal adenomas and cancers. FUND: Alpe d'Huzes- Dutch Cancer Society (project number NKI2013-6338).

Specific types of human papillomavirus found in benign proliferations and carcinomas of the skin in immunosuppressed patients.

A total of 118 biopsies from skin lesions of 46 renal allograft patients was analyzed for human papillomavirus (HPV) DNA by polymerase chain reaction with degenerate primers and also partially by subsequent sequencing of the amplified fragment. Sixty-two % of the benign proliferations (31 of 50) contained DNA of known HPV types as well as HPV sequences related to a number of epidermodysplasia verruciformis-associated HPV types. HPV DNA sequences were found in 14 (56%) of 25 biopsies from squamous cell and basal cell carcinomas. One squamous cell carcinoma contained HPV 41 DNA. A novel 640-base pair fragment sharing homology with HPV 29 (82.7%) was found in 15% (3 of 20) of squamous cell carcinomas, in 9.4% (3 of 32) of dysplastic warts and in 8.5% (4 of 47) common warts. The remaining positive carcinoma biopsies contained HPV-related DNA in such a low copy number that additional analysis is required. The identification of new HPV types in skin cancers of immunosuppressed patients (other than epidermodysplasia verruciformis patients) further expands the spectrum of HPV-linked human malignancies and permits new approaches to study the pathogenesis of skin cancers.

Galactomannan does not precede major signs on a pulmonary computerized tomographic scan suggestive of invasive aspergillosis in patients with hematological malignancies.

BACKGROUND: Detection of serum galactomannan (GM) antigen and presence of the halo sign on a pulmonary computerized tomographic (CT) scan have a high specificity but a low sensitivity to diagnose invasive aspergillosis (IA) in patients at risk for this disease. To our knowledge, the relationship between the time at which pulmonary infiltrates are detected by CT and the time at which GM antigens are detected by enzyme immunoassay (EIA) has not been studied. METHODS: In a prospective study, tests for detection of GM were performed twice weekly for patients with hematological malignancies who had undergone hematopoetic stem cell transplantation (HSCT) or had received induction and/or consolidation chemotherapy. A pulmonary CT scan was performed once weekly. Infiltrates were defined as either major or minor signs. IA was classified as proven, probable, or possible, in accordance with the definition stated by the European Organization for Research and Treatment of Cancer-Invasive Fungal Infections Cooperative Group and the National Institute of Allergy and Infectious Diseases Mycoses Study Group. RESULTS: We analyzed 161 episodes of infection in 107 patients (65 allogeneic HSCT recipients, 30 autologous HSCT recipients, and 66 induction and/or consolidation chemotherapy recipients). A total of 109 episodes with no IA, 32 episodes with possible IA, and 20 episodes with probable or proven IA were identified. Minor pulmonary signs were detected by CT in 70 episodes (43%), and major pulmonary signs were detected by CT in 11 episodes (7%). Univariate and multivariate analyses revealed no significant association between detection of GM by EIA and detection of abnormal pulmonary signs by CT. A significant association was found between GM levels and receipt of piperacillin-tazobactam. GM test results were not positive before major signs were seen on CT images. Only 7 (10%) of 70 patients with minor pulmonary signs had positive GM test results before detection of the greatest pathologic change by CT. CONCLUSIONS: We show that detection of GM by EIA does not precede detection of major lesions by pulmonary CT. In the clinical setting, the decision to administer mold-active treatment should based on detection of new pulmonary infiltrates on CT performed early during infection, rather than on results of EIA for detection of GM.

Software scripts for quality checking of high-throughput nucleic acid sequencers.

We have developed a graphical interface to allow the researcher to view and assess the quality of sequencing results using a series of program scripts developed to process data generated by automated sequencers. The scripts are written in Perl programming language and are executable under the cgibin directory of a Web server environment. The scripts direct nucleic acid sequencing trace file data output from automated sequencers to be analyzed by the phred molecular biology program and are displayed as graphical hypertext mark-up language (HTML) pages. The scripts are mainly designed to handle 96-well microtiter dish samples, but the scripts are also able to read data from 384-well microtiter dishes 96 samples at a time. The scripts may be customized for different laboratory environments and computer configurations. Web links to the sources and discussion page are provided.

Reduction of levels of nuclear-associated protein in heated cells by cycloheximide, D2O, and thermotolerance.

Hyperthermia increases levels of nuclear-associated proteins in a manner that correlates with cell killing. If the increase in nuclear-associated proteins represents a lethal lesion then treatments that protect against killing by heat should reduce and/or facilitate the recovery of levels of the proteins in heated cells. This hypothesis was tested using three heat protection treatments: cycloheximide, D2O, and thermotolerance. All three treatments reduced levels of the proteins measured immediately following hyperthermia at 43.0 or 45.5 degrees C, with the greatest reduction occurring at 43.0 degrees C. In addition to reducing the proteins, thermotolerance facilitated the recovery of the proteins to control levels following hyperthermia. Thus thermotolerance may protect cells by both reducing the initial heat damage and facilitating recovery from that damage. Cycloheximide and D2O did not facilitate recovery of nuclear-associated proteins, suggesting that their protection against cytotoxicity related to the proteins resulted solely from their reduction of increases in levels of the proteins. All three treatments have been shown to stabilize cellular proteins against thermal denaturation. The results of this study suggest that the increase in nuclear-associated proteins may result from thermally denatured proteins adhering to the nucleus and that it is the ability of cycloheximide, D2O, and thermotolerance to thermostabilize proteins that reduces the increase in levels of the proteins within heated cells.

Aneuploidy precedes and segregates with chemical carcinogenesis.

A century ago, Boveri proposed that cancer is caused by aneuploidy, an abnormal balance of chromosomes, because aneuploidy correlates with cancer and because experimental aneuploidy generates "pathological" phenotypes. Half a century later, when cancers were found to be nonclonal for aneuploidy, but clonal for somatic gene mutations, this hypothesis was abandoned. As a result, aneuploidy is now generally viewed as a consequence, and mutated genes as a cause of cancer. However, we have recently proposed a two-stage mechanism of carcinogenesis that resolves the discrepancy between clonal mutation and nonclonal karyotypes. The proposal is as follows: in stage 1, a carcinogen "initiates" carcinogenesis by generating a preneoplastic aneuploidy; in stage 2, aneuploidy causes asymmetric mitosis because it biases balance-sensitive spindle and chromosomal proteins and alters centrosomes both numerically and structurally (in proportion to the degree of aneuploidy). Therefore, the karyotype of an initiated cell evolves autocatalytically, generating ever-new chromosome combinations, including neoplastic ones. Accordingly, the heterogeneous karyotypes of "clonal" cancers are an inevitable consequence of the karyotypic instability of aneuploid cells. The notorious long latent periods, of months to decades, from carcinogen to carcinogenesis, would reflect the low probability of evolving by chance karyotypes that compete favorably with normal cells, in principle analagous to natural evolution. Here, we have confirmed experimentally five predictions of the aneuploidy hypothesis: (1) the carcinogens dimethylbenzanthracene and cytosine arabinoside induced aneuploidy in a fraction of treated Chinese hamster embryo cells; (2) aneuploidy preceded malignant transformation; (3) transformation of carcinogen-treated cells occurred only months after carcinogen treatment, i.e., autocatalytically; (4) preneoplastic aneuploidy segregated with malignant transformation in vitro and with 14 of 14 tumors in animals; and (5) karyotypes of tumors were heterogeneous. We conclude that, with the carcinogens studied, aneuploidy precedes cancer and is necessary for carcinogenesis.

How aneuploidy may cause cancer and genetic instability.

It has been difficult to find a common cause for the many and complex phenotypes of cancer such as dedifferentiation, invasiveness, abnormal morphology, growth rate and metabolism, genetic instability, progression to malignancy, cellular heterogeneity of phenotypes and karyotypes, and clonal origin despite heterogeneity. Over 100 years ago aneuploidy, an abnormal balance of chromosomes, was proposed to cause cancer. However, the aneuploidy hypothesis has since been abandoned, in favor of the gene mutation hypothesis, because it could not offer conventional explanations for cancer-specific phenotypes. For example, the aneuploidy hypothesis seemed unable to (i) explain the genesis of abnormal, cancer-specific phenotypes, (ii) reconcile the heterogeneous karyotypes with the clonal origin of cancers, (iii) explain aneuploidy in non-cancerous cells, and (iv) explain how carcinogens would cause aneuploidy. Here we introduce new evidence that aneuploidy offers a simple, coherent explanation of all cancer-specific phenotypes: (i) Congenital and experimental aneuploidy is now known to generate abnormal phenotypes, such as Down syndrome in humans and cancer in animals. (ii) Based on metabolic control analysis, we have derived equations that correlate degrees of aneuploidy with the resulting phenotype abnormalities. These equations suggest that aneuploidy must exceed a certain threshold to generate cancer-specific phenotypes. Therefore, we propose that multistep carcinogenesis corresponds to multiple steps of aneuploidization. (iii) Aneuploidy is also sufficient to explain cancer-specific, karyotypic instability. Since aneuploidy imbalances the highly balance-sensitive components of the spindle apparatus it destabilizes symmetrical chromosome segregation. This autocatalytic instability is the reason why cancers have heterogeneous karyotypes, but are clonal for aneuploidy. Progression to malignancy corresponds to selection of ever more aggressive karyotypic variants. (iv) Both non-genotoxic and genotoxic carcinogens can cause aneuploidy by physical or chemical interaction with mitosis proteins. We conclude that aneuploidy offers a mechanism of phenotype alteration which--above a certain threshold--is sufficient to cause all cancer-specific phenotypes, and is independent of gene mutation.

Development of a community-based diabetes management program for Pacific Islanders.

PURPOSE: This study examined the perception of diabetes among a sample of Pacific Islanders in Honolulu, Hawaii. All 23 participants were diagnosed with type 2 diabetes, ranged in age from 21 to 70 years, and had glycosylated hemoglobin levels of 5.8% to 13.9%. METHODS: Four focus groups were held in English and audiotaped. Outreach workers served as translators and comoderators. The content of transcripts was analyzed with Ethnograph software by investigators. The priority issues were confirmed by the comoderators and participants. RESULTS: Participants perceived diabetes as full of complications, emotions, symptoms, and behavior changes. Responses to hyperglycemia were fear, frustration, and uncertainty. Barriers to staying on the prescribed diet were habit, cultural ritual, ideal body image, and limited budget. CONCLUSIONS: Participants suggested that helpful activities would include walking/support group, cooking class, community healthy food store, translated material, and family participation. A community-based diabetes program has been developing as a result of the focus group findings.

CLUSEAN: a computer-based framework for the automated analysis of bacterial secondary metabolite biosynthetic gene clusters.

Bacterial secondary metabolites are an important source of antimicrobial and cytostatic drugs. These molecules are often synthesized in a stepwise fashion by multimodular megaenzymes that are encoded in clusters of genes encoding enzymes for precursor supply and modification. In this work,we present an open source software pipeline, CLUSEAN (CLUster SEquence ANalyzer) that helps to annotate and analyze such gene clusters. CLUSEAN integrates standard analysis tools, like BLAST and HMMer, with specific tools for the identification of the functional domains and motifs in nonribosomal peptide synthetases (NRPS)/type I polyketide synthases (PKS) and the prediction of specificities of NRPS.

Microelectrode measurements of the transmembrane potential in baby hamster kidney, (Chinese hamster ovary), NG108-15 neuroblastoma and Swiss 3T3 cells at 37.0 or 43.0 degrees C.

Hyperthermia affects the physical state and function of the plasma membrane. This could alter the transmembrane potential (Vm) and associated functions in a manner that promotes cell killing. Previous investigations have reported differing results of the effect of heat on Vm, possibly due to artifacts associated with the methods employed to measure Vm indirectly. One such artifact is a membrane depolarization induced by cationic probes, as demonstrated in this paper. In this study, glass microelectrodes were used to avoid these artifacts and to make direct electrical measurements of Vm. Following 25 min-30 min at 43.0 degrees C, The mean Vm of Chinese hamster ovary (CHO) cells, within clusters of six or more cells, decreased from -16 +/- 5 to -38 +/- 6 mV, and remained at these levels during incubation times up to 3 h. All CHO cells resumed a normal Vm within 4.5 h after returning to 37.0 degrees C, regardless of the time of exposure at 43.0 degrees C (0.5 to 3.0 h, with survival levels of 0.7 and 0.001, respectively). The membrane hyperpolarization decreased with cell to cell contact to where isolated cells exhibited no hyperpolarization. CHO cultures with different cell densities (number of cells per cm2), and thus differing degrees of cell to cell contact, were heated and then subjected to the colony formation assay. The degree of cell to cell contact at the time of heating had no effect on survival. Hence, the heat-induced, cell contact dependent hypolarization of CHO cell membranes was unrelated to clonogenic survival.(ABSTRACT TRUNCATED AT 250 WORDS)

Genetic instability of cancer cells is proportional to their degree of aneuploidy.

Genetic and phenotypic instability are hallmarks of cancer cells, but their cause is not clear. The leading hypothesis suggests that a poorly defined gene mutation generates genetic instability and that some of many subsequent mutations then cause cancer. Here we investigate the hypothesis that genetic instability of cancer cells is caused by aneuploidy, an abnormal balance of chromosomes. Because symmetrical segregation of chromosomes depends on exactly two copies of mitosis genes, aneuploidy involving chromosomes with mitosis genes will destabilize the karyotype. The hypothesis predicts that the degree of genetic instability should be proportional to the degree of aneuploidy. Thus it should be difficult, if not impossible, to maintain the particular karyotype of a highly aneuploid cancer cell on clonal propagation. This prediction was confirmed with clonal cultures of chemically transformed, aneuploid Chinese hamster embryo cells. It was found that the higher the ploidy factor of a clone, the more unstable was its karyotype. The ploidy factor is the quotient of the modal chromosome number divided by the normal number of the species. Transformed Chinese hamster embryo cells with a ploidy factor of 1.7 were estimated to change their karyotype at a rate of about 3% per generation, compared with 1.8% for cells with a ploidy factor of 0.95. Because the background noise of karyotyping is relatively high, the cells with low ploidy factor may be more stable than our method suggests. The karyotype instability of human colon cancer cell lines, recently analyzed by Lengnauer et al. [Lengnauer, C., Kinzler, K. W. & Vogelstein, B. (1997) Nature (London) 386, 623-627], also corresponds exactly to their degree of aneuploidy. We conclude that aneuploidy is sufficient to explain genetic instability and the resulting karyotypic and phenotypic heterogeneity of cancer cells, independent of gene mutation. Because aneuploidy has also been proposed to cause cancer, our hypothesis offers a common, unique mechanism of altering and simultaneously destabilizing normal cellular phenotypes.

The wheat D-genome HMW-glutenin locus: BAC sequencing, gene distribution, and retrotransposon clusters.

A bacterial-artificial-chromosome (BAC) clone from the genome of Triticum tauschii, the D-genome ancestor of hexaploid bread wheat, was sequenced and the presence of the two paralogous x- and y-type high-molecular-weight (HMW) glutenin genes of the Glu-D1 locus was confirmed. These two genes occur in the same orientation, are 51,893 bp apart, and the separating DNA includes a 31,000-bp cluster of retrotransposons. A second retrotransposon cluster of 32,000 bp follows the x-type HMW-glutenin gene region. Each HMW-glutenin gene is found within a region of mainly unique DNA sequence which includes multiple additional genes including an active endosperm globulin gene not previously reported in the Triticeae family, a leucine-rich-repeat (LRR) type gene truncated at the 5' end of the BAC, a kinase gene of unknown activity, remnants of a paralogous second globulin gene, and genes similar to two hypothetical rice genes. The newly identified globulin genes are assigned to a locus designated Glo-2. Comparison to available orthologous regions of the wheat A and B genomes show rapid sequence divergences flanking the HMW-glutenin genes, and the absence of two hypothetical and unknown genes found 5' to the B-genome x-type ortholog. The region surrounding the Glu-D1 locus is similar to other reported Triticeae BAC sequences; i.e. small gene islands separated by retrotransposon clusters.

Electroporation of extraneous proteins into CHO cells: increased efficacy by utilizing centrifugal force and microsecond electrical pulses.

A novel electroporation system employing an oscillating electric pulse and centrifugal force was used to introduce extraneous proteins into CHO cells. Following the electrical pulse, the compression and subsequent rebound induced by the centrifugal acceleration and deceleration, respectively, enhanced protein uptake, presumably by a hydrodynamic pumping of extracellular solutions through the permeabilized membrane. Protein uptake was quantitated by measuring the amount of radiolabeled, extraneous, CHO proteins introduced into unlabeled CHO cells. The amount of protein introduced into electroporated CHO cells was enhanced up to four-fold by a combination of electric pulse and centrifugal force compared to that introduced by electric pulse only. The optimum gradient of centrifugal force (GCF, temporal change of centrifugal force) was 590 and -470 g/s during acceleration and deceleration, respectively. The optimum electric field was 5 kV/cm with a 30-microsecond pulse length. At this optimum electroporation condition, approximately 5 pg of proteins (up to 200 kDa molecular weight) were introduced per CHO cell. These same settings also permitted electroporation of other membrane impermeable substances including propidium iodide and ethidium bromide. Introduction of extraneous materials into the cytoplasm during electroporation was confirmed by the ability of anti alpha-tubulin to stain the microtubules and propidium iodide and ethidium bromide to stain the nuclei. Cells electroporated with optimum device settings exhibited no significant decrease in clonogenic survival.

Sensitization to hyperthermia by 3,3'-dipentyloxacarbocyanine iodide: a positive correlation with DNA damage and negative correlations with altered cell morphology, oxygen consumption inhibition, and reduced ATP levels.

The cyanine dye 3,3'-dipentyloxacarbocyanine iodide (DiOC5(3)) (concentrations of 0.5 microgram/ml to 5.0 micrograms/ml) was shown to be a potent sensitizer of Chinese hamster ovary (CHO) cells to hyperthermic cell killing at 43.0 degrees C or 45.5 degrees C, while exhibiting no cytotoxicity at 37.0 degrees C. Sensitization to hyperthermic cell killing was accompanied by an increase in damage to the DNA, as measured by DNA unwinding. The increased DNA damage correlated qualitatively with the enhanced heat killing induced by DiOC5(3). This correlation was better in cells heated at 43.0 degrees C than in those heated at 45.5 degrees C. DiOC5(3) is known to affect other cellular functions. It inhibits electron transport, uncouples oxidative phosphorylation, and inhibits calcium ATPases. The effects of DiOC5(3) on oxygen consumption and ATP content were therefore measured at 37.0 degrees C and at hyperthermic temperatures. The results demonstrated that inhibition of oxygen consumption and reduction of cellular ATP levels played no role in inducing heat sensitization in DiOC5(3)-treated cells, or in causing cell death in cells treated with heat alone.

Nicotine-induced airway smooth muscle contraction: neural mechanisms involving the airway epithelium. Functional and histologic studies in vitro.

To assess the mechanism of and the role of the epithelium in nicotine-induced bronchoconstriction in vitro, we performed a combined functional and histologic study. Functional study: We suspended tracheal strips or rings from 16 ferrets (1124 +/- 561 g, mean +/- SD) in organ baths. Alternate tracheal strips had their epithelium removed. Dose-response curves to acetylcholine (ACh) and nicotine were established for pairs of tissues with and without epithelium, each pair receiving only one dose of nicotine. Nicotine induced brief muscle contractions not exceeding 25% of the ACh-induced maximum. Contractions were blocked by hexamethonium and 10(-7) M atropine and were abolished or inhibited strongly by tetrodotoxin (TTX), suggesting the involvement of nicotinic neuronal and muscarinic smooth muscle receptors. Removal of the epithelium strongly inhibited contractions at concentrations of nicotine greater than 3 x 10(-5) M which completely removed any dose-response effect. ACh-induced contractions were unchanged, demonstrating smooth muscle integrity. We suggest that the removal of the epithelium attenuates nicotine-induced bronchoconstriction through the removal of nerves running in or close to the epithelium. Histologic study: In tracheae from 15 ferrets (8 male, 7 female), mean weight (+/- SD) 1288 (+/- 470) g, we examined 4 techniques of epithelium removal: (1) gentle scraping with a scalpel blade moved backwards (away from the cutting edge), (2) moving a Q-tip through the unopened tracheal tube without lateral pressure, and (3, 4) stroking the mucosa of opened tracheal segments with a Q-tip, exerting (3) light or (4) moderate pressure. All methods were equally (97%-100%) efficient in removing the epithelium but differed in the amount of damage caused to the basement membrane and/or submucosal tissue. Method (2) caused less damage to the basement membrane than the other methods but still removed almost one-third of it. The study showed that complete removal of the epithelium is at the expense of the submucosa and that a given result of "epithelium removal" is also attributable to removal of the neighboring subepithelial structures.