bluuebunny/crossref_metadata_2025_split huggingface dataset:
A laser microbeam as a tool to introduce genes into cells and organelles of higher plants
Authors: Weber Gerd , Monajembashi Shamci , Wolfrum Jürgen , Greulich Karl‐Otto 
Published: July 2012

AbstractA number of methods have become available to introduce genes into animal cells. In plants the rigid cell wall has presented a substantial barrier to similar efforts. Using protoplasts represents one way to overcome the obstacles to gene transfer. In many species these wall‐less cells, however, are sensitive to manipulations and do not regenerate to plants. Furthermore, direct gene transfer into organelles is even further complicated by the fact that DNA has to pass through two membrane systems. —Recently a method has been developed to deliver DNA randomly to cells with a particle gun [1]. It is very desirable, however, to introduce DNA into specifically selected cells or their organelles. —A laser beam focussed to its diffraction limits and coupled into a microscope provides a tool to cut openings of less than 1 μm into cell walls or membranes. Under visual control cells can be selected for gene transfer or for surgical manipulation [2]. Direct transformation with cloned DNA was achieved in mammalian cells [3,4], —Now this tool was used on oilseed rape (Brassica napus). With a laser microbeam DNA was introduced into cells and microspores of Brassica napus [5,6]. Individual cells were placed in the light path of the microscope and a single laser pulse was released at the cell wall and membrane. At the site of the laser focus wall and membrane were opened. At the time of the experiment the cells were incubated in a hypotonic buffer containing DNA. The nucleic acid was taken up into the cells. The opening in the membrane was only temporary and closed within less than 5 s after the laser pulse. The cells or microspores developed into colonies or embryos respectively with a frequency of 30–50% of the untreated controls. —Using the same technique DNA was also integrated into isolated chloroplasts [7]. Furthermore DNA can be incorporated into chloroplasts inside of a cell, large quantities of DNA were first brought into the cytoplasma. Then the laser beam was focussed on each chloroplast inside of the cell and a single laser pulse was released at each organelle. Again a small opening was cut into the membrane allowing the DNA to enter the organelle [6]. This opening closed again within 1.2 s as could be demonstrated by computer enhanced image analysis. —Laser microbeams provide a new powerful tool for introducing DNA into plant cells and their organelles as well as for analyzing chromosomes.
Excimer laser angioplasty —experimental and first clinical results
Authors: Mohr Friedrich W. , Kirchhoff Paul G. 
Published: July 2012

AbstractThe following paper describes the rationale for Excimer Laser Angioplasty, and discusses the development of a special designed Excimer Laser and catheter system for Laser Angioplasty in femoral and coronary arteries.Methods: A long pulsed (150 ns) Excimer Laser, operating at 308 nm, was evaluated in combination with a special designed silica based catheter system. We used 600 μm single and 6 × 200/6 × 700 μm multiple fiber catheter system to recanalize obstructed canine femoral arteries. The catheter systems were also tested in porcine anormal coronaries. Finally, Excimer Laser Angioplasty was performed in human femoral and popliteal arteries.Results: Using a long pulsed Excimer Laser at 308 nm fiberoptical transmission was excellent, without fiber breakdown. In addition, the catheter systems, especially the multiple fiber system proved to be flexible enough, even for percutaneous intracoronary application. No vessel wall perforation occurred.In 16/18 patients femoro‐popliteal occlusions were successfully recanalized in combination with subsequent balloon angioplasty.Conclusions: Excimer Laser Angioplasty is feasible in man. It increases the number of successful non operative treatments in vascular diseases and might even be an additional surgical tool. Long pulse Excimer Lasers allow easy fiberoptical transmission, and therefore might be favorable.
A DFDL UV picosecond fluorescence spectrometer: Application to aqueous solutions of peptides and nucleotide dye conjugates
Authors: Schwarzwald Ralf , Seidel Claus , Goody Roger S. , Kühn Klaus P. , Greulich Karl Otto 
Published: July 2012

AbstractUsing a new type of fluorescence lifetime spectrometer, the time resolution of single shot fluorescence detection is improved by two orders of magnitude. The spectrometer is based on a streak camera and an excimer laser pumped distributed feedback dye laser (DFDL) providing UV pulses of 50 μJ and 15 ps FWHM, corresponding to a peak power of ∼ 5 · 106 W in the ultraviolet. —This spectrometer is used to investigate the fluorescence decay of peptides containing a tyrosine as the single fluorophore. Peptides with tyrosine at the N‐terminus reveal a biexponential decay, while peptides with C‐terminal tyrosine are mainly monoexponential. This difference can be explained by the relative orientation of the fluorescing phenol ring and the quenching peptide bond. —The fluorescence decay of a number of peptides with tyrosine in a non terminal position can be described by two lifetimes, 2.3 · 0.1 ns and 380 ± 70 ps, where the percentage of the long lifetime increases to up to 100% when the rotational flexibility of the peptide chain decreases, either due to increasing weight of the chain or due to formation of an H‐bridge. —Similar processes seem to be relevant for the fluorescence of the dye coumarin 120 coupled to nucleotides. The fluorescence lifetime of such molecules is significantly different, so that the four DNA nucleotides can be identified on the basis of the fluorescence decay of the attached dye.
UV laser crosslinking of proteins with nucleic acids
Authors: Kubasek William L. , Hockensmith Joel W. , Vorachek William , Spann Dennis , Munck Kirsten T. , Evertsz Elizabeth , Von Hippel Peter H. 
Published: July 2012

AbstractFor some years it has been known that proteins and nucleic acids can be crosslinked together by ultra‐violet light. This phenomenon has been exploited in a number of studies investigating protein‐nucleic acid interactions. We have further developed this approach by employing a high‐powered pulsed UV laser as a radiation source. Using model protein‐nucleic acid systems we have characterized a number of aspects of the crosslinking process. We have found that the optimal wavelength for crosslinking proteins to nucleic acids falls within the major absorption band of the nucleic acid. Thymidine residues appear to exhibit the greatest amount of crosslinking, followed by cytosine, which crosslinks with an efficiency that is about 100‐fold less. We have found that the crosslinking process is critically dependent on the exact geometry of the protein‐nucleic acid system, in such a way that only those partners that are involved in a very intimate contact undergo crosslinking. The rapid photon delivery time of the laser presents many advantages in crosslinking studies. Problems associated with photodegradation products, substrate exhaustion and general protein degradation can be avoided. Furthermore, since all of the crosslinking can be achieved in one short pulse lasting only several nanoseconds the distribution of proteins reflects an equilibrium that has been essentially frozen at a particular instant in time. As a result protein‐nucleic acid contact information can be interpreted within a temporal context, leading to a more complete understanding of how a particular protein‐nucleic acid complex functions.
Energetics of an Electrochemical Reaction Derived from the Intersection of Tafel Lines Determined at Different Temperatures
Authors: Damjanović A. , Conway B. E. , S̄epa D. B. 
Published: July 2012

AbstractUnder most conditions in electrode kinetics, the slopes of Tafel relationships for a given electrode process are dependent on temperature. Tafel lines determined at different temperatures therefore intersect at some singular potential, Ecr, for which the Gibbs energy of activation must be zero. The absolute value of the Gibbs energy of activation can then be evaluated by reference to this critical potential. For the oxygen reduction reaction at Pt electrodes in acid solutions, Ecr = 0.36 E vs. RHE. This critical potential yields a value of the Gibbs energy of activation at 0.8 V vs. RHE of 21 kJ mol‐1. A comparison of this energy with the apparent enthalpies of activation Δ≠Hap (= 21 and 24 kJ mol‐1), obtained previously from the Arrhenius plots at the same potential and in the same solution, shows that TΔS≠ is small. The values for the enthalpic component, βH (= 0.44), and entropic component, Tβs (= 0.07 at room temperature), of the overall symmetry factor, β, are determined. They show that, in this case, the kinetics are controlled mainly by the effect of electrode potential on the enthalpic component of the Gibbs energy of activation. It is shown that the electron energy level, ϵ0, of the reacting complex in the ground‐state can be obtained from Ecr. For oxygen reduction at Pt, it is ‐4.72 eV with respect to the electron energy in vacuum.
DTA and dielectric measurements at high pressures of t‐butyl‐bromide
Authors: Kreul Hans‐Georg , Hartmann Martina , Edelmann Ralph , Würflinger Albert , Urban Stanislaw 
Published: July 2012

AbstractThe phase behaviour and static permittivity ε of liquid and solid t‐butylbromide (2‐bromo‐2‐methylpropane) have been determined as a function of temperature (200–300 K) and pressure up to 300 MPa. Two well‐known solid phase transitions have been pursued to higher pressures but there is no evidence of new pressure‐induced solid phases within the experimental range. The static permittivity increases on rising pressure and decreasing temperature and maintains high values for two orientationally disordered phases. The Kirkwood correlation factor is approximately unity and does not change on freezing.
Comparison of mutation findings in ZIC2 between microform and classical holoprosencephaly in a Brazilian cohort
Authors: Ribeiro Lucilene A. , Roessler Erich , Hu Ping , Pineda‐Alvarez Daniel E. , Zhou Nan , Jones MaryPat , Chandrasekharappa Settara , Richieri‐Costa Antonio , Muenke Maximilian 
Published: July 2012

AbstractBACKGROUNDHoloprosencephaly is the most frequent congenital malformation of the forebrain in humans. It is anatomically classified by the relative degree of abnormal formation and separation of the developing central nervous system. Mutations of ZIC2 are the second most common heterozygous variations detected in holoprosencephaly (HPE) patients. Mutations in most known HPE genes typically result in variable phenotypes that rage from classic alobar HPE to microforms represented by hypotelorism, solitary central maxillary incisor (SCMI), and cleft lip/palate, among others. Patients with HPE owing to ZIC2 mutations have recently been described by a distinct phenotype compared with mutations in other HPE causative genes.METHODSWe report the comparison of ZIC2 molecular findings by Sanger bidirectional DNA sequencing and ad hoc genotyping in a cohort of 105 Brazilian patients within the clinical spectrum of HPE, including classic and microform groups.RESULTSWe detected a total of five variants in the ZIC2 gene: a common histidine tract expansion c.716_718dup (p.His239dup), a rare c.1377_1391del_homozygous (p.Ala466_470del, or Ala 15 to 10 contraction), a novel intronic c.1239+18G>A variant, a novel frameshift c.1215dupC (p.Ser406Glnfs*11), and a c.1401_1406dup (p.Ala469_470dup, or alanine tract expansion to 17 residues).CONCLUSIONSFrom these patients, only the latter two mutations found in classic HPE are likely to be medically significant. In contrast, variants detected in the microform group are not likely to be pathogenic. We show conclusively that the histidine tract expansion is a polymorphic alteration that demonstrates considerable differences in allele frequencies across different ethnic groups. Therefore, careful population studies of rare variants can improve genotype‐phenotype correlations. Birth Defects Research (Part A) 2012. © 2012 Wiley Periodicals, Inc.
Counseling about risks of congenital anomalies from prescription opioids
Authors: Brennan Matthew C. , Rayburn William F. 
Published: July 2012

AbstractThe use of prescription opioids is becoming an increasing problem among women of reproductive age. More than half of pregnancies are unintended; therefore, many first‐trimester exposures to opioids occur before pregnancy confirmation. Studies are limited about the fetal risks to opioid exposure in early pregnancy. One large study demonstrated an increased risk of certain heart defects and spina bifida with first‐trimester exposure to opioids. It is important to counsel women whose fetuses were exposed to opioids in early pregnancy about the potential risks, encourage them to cease using opioids or seek alternative treatments when appropriate, and use the lowest effective dose when opioid treatment is to be continued. It is also valuable to screen for anatomic abnormalities such as neural tube and cardiac defects with available maternal serum testing and ultrasound imaging in the early second trimester. Birth Defects Research (Part A) 94:620–625, 2012. © 2012 Wiley Periodicals, Inc.
Development and homeostasis of “resident” myeloid cells: The case of the microglia
Authors: Gomez Perdiguero Elisa , Schulz Christian , Geissmann Frederic 
Published: July 2012

AbstractMicroglia, macrophages of the central nervous system, play an important role in brain homeostasis. Their origin has been unclear. Recent fate‐mapping experiments have established that microglia mostly originate from Myb‐independent, FLT3‐independent, but PU.1‐dependent precursors that express the CSF1‐receptor at E8.5 of embryonic development. These precursors are presumably located in the yolk sac (YS) at this time before invading the embryo between E9.5 and E10.5 and colonizing the fetal liver. Indeed, the E14.5 fetal liver contains a large population of Myb‐independent YS‐derived myeloid cells. This myeloid lineage is distinct from hematopoietic stem cells (HSCs), which require the transcription factor Myb for their development and maintenance. This “yolky” beginning and the independence from conventional HSCs are not unique to microglia. Indeed, several other populations of F4/80‐positive macrophages develop also from YS Myb‐independent precursors, such as Kupffer cells in the liver, Langerhans cells in the epidermis, and macrophages in the spleen, kidney, pancreas, and lung. Importantly, microglia and the other Myb‐independent macrophages persist, at least in part, in adult mice and likely self‐renew within their respective tissues of residence, independently of bone marrow HSCs. This suggests the existence of tissue resident macrophage “stem cells” within tissues such as the brain, and opens a new era for the molecular and cellular understanding of myeloid cells responses during acute and chronic inflammation. © 2012 Wiley Periodicals, Inc.
Greening organizations through leaders' influence on employees' pro‐environmental behaviors
Authors: Robertson Jennifer L. , Barling Julian 
Published: July 2012

SummaryClimate change is a serious global issue that poses many risks to environmental and human systems. Although human activity is cited as the main cause of climate change and organizations significantly contribute to climate change, research that investigates workplace pro‐environmental behaviors remains scarce. We develop and test a model that links environmentally‐specific transformational leadership and leaders' workplace pro‐environmental behaviors to employees' pro‐environmental passion and behaviors. Structural equation modeling on data from 139 subordinate–leader dyads (M ages = 37.42 and 40.17 years, respectively) showed that leaders' environmental descriptive norms predicted their environmentally‐specific transformational leadership and their workplace pro‐environmental behaviors, both of which predicted employees' harmonious environmental passion. In turn, employees' own harmonious environmental passion and their leaders' workplace pro‐environmental behaviors predicted their workplace pro‐environmental behaviors. These findings show that leaders' environmental descriptive norms and the leadership and pro‐environmental behaviors they enact play an important role in the greening of organizations. Conceptual and practical implications are discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Using diversity interventions to increase cervical screening of lesbian and bisexual women
Authors: Carter Lynne , Hedges Lesley , Congdon Shirley 
Published: July 2012

AbstractDespite increasing recognition and acceptance in many areas, lesbians, gay men, and bisexual people are still unnoticed service users whose needs the National Health Service (NHS) has not recognized and served well. This article reports the first stages of a small‐scale, practitioner‐led action research study undertaken to increase access to cervical screening for lesbian and bisexual women by planning and delivering service enhancements following in‐depth individual and small‐group interviews with local lesbians and bisexual women. These interviews provided rich data that provided insight into the women's health beliefs and experiences related to cervical screening. These experiences directly informed the enhancements made to cervical screening services. The authors describe the factors that made this action research successful, which may have multiple applications across other diversity interventions.
Photodynamic therapy as an alternative treatment for disinfection of bacteria in oral biofilms
Authors: Mang Thomas S. , Tayal Dharam P. , Baier Robert 
Published: July 2012

AbstractBackground and ObjectivesBiofilm‐related diseases such as caries and periodontal disease are prevalent chronic oral infections which pose significant oral and general health risks. Biofilms are sessile communities attached to surfaces. Photodynamic therapy (PDT) has been demonstrated to have a significant anti‐microbial effect and presents as an alternative to treating biofilm‐related disease. The aim of this study was to determine the ability of porfimer sodium induced PDT to treat localized infections of Streptococcus mutans in biofilm communities.Materials and MethodsReproducible biofilms were formed by S. mutans strain ATCC 27351 growing in log phase at 37°C in Brain Heart Infusion medium, circulating through flow cells at 3 ml/minute for 36–48 hours. The photosensitizer used was porfimer sodium (Photofrin®) at 125 µg/ml with biofilm immersion times of 5 minutes and increasing energy density of post‐immersion laser illumination at 630 nm (100 mW/cm2). Resulting effects on bacterial viability in the biofilms were tracked by monitoring alamarBlue® conversion. Supplementary data characterizing the biofilms before and after exposure to PDT were acquired by Multiple Attenuated Internal Reflection Infrared Spectroscopy (MAIR‐IR).ResultsThe results of this study show that PDT using porfimer sodium and 630 nm laser light was effective in significantly reducing the viability of S. mutans biofilms. Maximum effectiveness was seen when biofilms were exposed to both photosensitizer and light versus controls. Porfimer sodium incubation times as short as 5 minutes in solutions as dilute as 25 µg/ml and illuminated with as little as 30 J/cm2 resulted in significant decreases in viability of bacteria in biofilms. Optimum parameters appear to be 125 µg/ml porfimer sodium concentration and incubated for 5 minutes and 60 J/cm2 of light energy density.ConclusionsThis study has demonstrated that significant killing of the cariogenic organism S. mutans by the combination of a photosensitizer and the appropriate wavelength of laser light was possible even when the bacteria are embedded in an extracellular matrix. Lasers Surg. Med. 44: 588–596, 2012. © Wiley Periodicals, Inc.
The AdVance male sling as a minimally invasive treatment for intrinsic sphincter deficiency in patients with neurogenic bladder sphincter dysfunction: A pilot study
Authors: Groen Luitzen‐Albert , Spinoit Anne‐Françoise , Hoebeke Piet , Van Laecke Erik , De Troyer Bart , Everaert Karel 
Published: July 2012

AbstractAimsThe aim of the study was to evaluate feasibility, efficacy, and safety of the AdVance male sling in neuropathic male patients with intrinsic sphincter deficiency.MethodsWe evaluated 20 consecutive male neuropathic patients (12 menigomyelocele and 8 lower spinal cord injured), age 23 ± 13 years (range 6–52 years) with urodynamically proven sphincter deficiency and stress urinary incontinence. In all patients an AdVance male sling was implanted from June 2007 to September 2009. Patients were evaluated with the number of pads per day (PPD), visual analogue scale (VAS) for continence and the International Consultation on Incontinence‐Short Form (ICIQ‐SF). Cure was defined as a 10 on VAS or using no pads for urinary leakage, improvement as >5 and failure as ≤5.ResultsPositive effect in 13 of 20 patients (65%) at 1‐year follow‐up: 8 patients were cured, 5 improved, and 7 failed. VAS score increased from baseline 2.6 (SD 2.0) to 7.2 (SD 3.5) at 12 months (P < 0.001). ICIQ‐SF decreased from 14 (SD 4.2) to 4 (SD 4.1) (P < 0.001). Friedman and Wilcoxon tests revealed at 1, 3, 6, 9, and 12 months significant improvement compared to baseline (P = 0.008).ConclusionsImplantation of the AdVance male sling is feasible in both adult and pediatric patients. A promising cure/improvement rate was achieved as well as a low complication rate. Neurourol. Urodynam. 31:1284–1287, 2012. © 2012 Wiley Periodicals, Inc.
A modulating effect of epigallocatechin gallate (EGCG), a tea catechin, on the bladder of rats exposed to water avoidance stress
Authors: Bazi Tony , Hajj‐Hussein Inaya Abdallah , Awwad Johnny , Shams Ali , Hijaz Miriana , Jurjus Abdo 
Published: July 2012

AbstractAimsTo examine the effect of epigallocatechin gallate (EGCG), a green tea catechin, on the bladder of rats exposed to water avoidance stress (WAS).MethodsTwenty female Sprague–Dawley rats were divided into four groups of five. The first group was exposed to WAS for7 days. The second group was pretreated with EGCG 1 mg/kg intraperitoneally (IP) for 7 days before exposure to WAS. The treatment was continued till the end of the experiment. The third group was placed on the platform in a container without water for 2 hr daily for 7 days (Sham WAS). The fourth group was pretreated with saline I.P. for 7 days before being exposed to sham WAS. Primary outcome: Bladder wall evaluation for signs of inflammation and total and activated mast cell counts. Secondary outcome: fecal pellet output and micturition frequency at baseline, day 1 and day 7.ResultsBladder walls from rats exposed to WAS revealed significantly higher inflammation score, total and degranulated mast cell counts compared to the sham WAS group. EGCG administration had an obvious protective effect on the bladder mucosa, as the inflammation score, total and degranulated mast cell counts were all significantly lower than in the WAS group. In the WAS group, fecal pellet output and micturition frequency increased above baseline throughout the experiment. Comparison of sham WAS group versus sham WAS with saline revealed no statistically significant difference in any parameter.ConclusionsEGCG given at 1 mg/kg I.P to rats has a significant protective effect against bladder degenerative changes following WAS. Neurourol. Urodynam. 32: 287–292, 2013. © 2012 Wiley Periodicals, Inc.