bluuebunny/crossref_metadata_2025 huggingface dataset:
Adrenocortical insufficiency is not a problem in preterm infants treated with antifungal prophylaxis with fluconazole
Authors: Costa S , Barone G , Vento G , Tirone C , Perelli S , Romagnoli C
Published: February 2014

Aim

Fluconazole prophylaxis of invasive fungal infections is a cornerstone of neonatal care, but in vitro studies have shown that it inhibits corticosteroid production. This study assessed whether preterm infants demonstrated an association between fluconazole administration, and its duration, and symptoms of adrenocortical insufficiency.

Methods

We compared two groups who were treated before and after we introduced the use of fluconazole to our neonatal intensive care unit. Infants with a gestational age of ≤27 weeks or with a birth weight of ≤750 g were considered for the retrospective analysis. In order to assess whether the duration of prophylaxis was related to adrenocortical insufficiency, regression models were performed in all preterm infants in the fluconazole group.

Results

The fluconazole group (n = 37) and nonfluconazole group (n = 41) were compared. No differences were found in the percentage of infants with symptoms of adrenocortical insufficiency, such as hypotension or need of vasopressor therapy. The incidence of hypotension and the use of vasopressor therapy were not related to duration of fluconazole prophylaxis.

Conclusion

Fluconazole and it duration were not associated with the incidence of symptoms related to adrenocortical insufficiency. Further prospective trials are needed to better define the relationship between fluconazole and adrenocortical insufficiency.
Young Women's Experiences as Consumers of Maternity Care in Queensland
Authors: Redshaw Maggie , Miller Yvette D , Hennegan Julie
Published: February 2014

Background

Young motherhood is commonly associated with vulnerabilities, stereotyping of young women's behavior, and poor outcomes for them and their children. The objective was to understand how maternity care is experienced by this group in the transition to parenthood.

Methods

Data from a large‐scale 2010 survey of women's experience of maternity care were analyzed using qualitative methods with open text responses.

Results

Overall, 7,193 women responded to the survey: 237 were aged 20 years or less. Most (83%) of these young women provided open text responses. The main themes were: “being a consumer,” “the quality of care,” “needing support,” and “pride in parenthood” whereas subthemes included “being young” and “how staff made me feel,” “testimonials for staff,” “not being left,” and “it is all worthwhile.”

Conclusion

Many young women responding described a positive experience. For many first‐time mothers this feeling marked a change in their identity. Nevertheless, staff perceptions and attitudes affected how they saw themselves and what they took away from their experience of maternity care. A key message for other women is offered, supporting and reinforcing their role as active and involved consumers who, in engaging with services, have to stand up for themselves and make their needs and wishes known.
ASIAN REAL EXCHANGE RATES AND OIL PRICES: A COINTEGRATION ANALYSIS UNDER STRUCTURAL BREAKS
Authors: Nusair Salah A. , Kisswani Khalid M.
Published: February 2014

We examine the long‐run relationship between Asian real exchange rates and oil prices in the presence of structural breaks. The relevance of considering breaks is demonstrated by utilizing the Johansen et al. procedure that allows for up to two predetermined breaks. Using conventional tests that do not consider breaks reveals no evidence of cointegration. However, the Johansen et al. procedure clearly demonstrates the importance of considering breaks and provides strong support for a stable long‐run relationship in all but Japan and the Philippines. Moreover, the results suggest evidence of bi‐directional causality in Malaysia and Thailand, uni‐directional causality from exchange rates to oil prices in Korea, the Philippines, and Singapore, uni‐directional causality from oil prices to the exchange rate in Indonesia, and no evidence of causality in Japan.
Automated Testing of Physical Security: Red Teaming Through Machine Learning
Authors: Thornton Chris , Cohen Ori , Denzinger Jörg , Boyd Jeffrey E.
Published: February 2014

Modern surveillance systems for practical applications with diverse and mobile sensors are large, complex, and expensive. It is known that unexpected behaviors can emerge from such systems, and when these behaviors correspond to weaknesses in a surveillance system, we call them emergent vulnerabilities. Given their cost and importance to security, it is essential to test these systems for such vulnerabilities prior to deployment. To that end, we automate the testing process with multiagent systems and machine learning. However, the conventional—and most intuitive–approach is to focus the machine learning on the subject system, which leads to a high‐dimensional problem that is intractable. Instead, we demonstrate in this paper that learning attacks on the system is tractable and provides a viable testing method. We demonstrate this with a series of studies in simulation and with a small‐scale model system featuring elements typically found in real physical surveillance systems. Our machine learning method finds successful attacks in simulation, which we can duplicate with the physical system. The method is scalable, with the implication that it could be used to test larger, real surveillance installations.
Measuring the effectiveness of interventions for children with cerebral palsy
Authors: Williams Elizabeth
Published: February 2014

This commentary is on the article by Hassani et al. on pages482–489of this issue.
Nitric oxide from mononuclear cells may be involved in platelet responsiveness to aspirin
Authors: López‐Farré Antonio J. , Modrego Javier , Azcona Luis , Guerra Reddy , Segura Antonio , Rodríguez Pablo , Zamorano‐León José J. , Lahera Vicente , Macaya Carlos
Published: February 2014

Background

Several mechanisms have been proposed to explain why some platelets have a reduced response to aspirin (ASA). Among them, it was reported an increased circulating level of vitamin‐D‐binding protein (DBP). In addition, nitric oxide (NO) released from mononuclear cells was involved in the antiplatelet effects of ASA. The aim was to analyse the relationship between platelet response to ASA and both NO generation and vitamin‐D‐binding protein content in mononuclear cells.

Materials and methods

Mononuclear cells were obtained from patients with stable coronary artery disease that were divided by a platelet functionality test (PFA‐100) as ASA‐sensitive (n = 23) and ASA resistant (n = 27).

Results

Both the release of NO (determined by nitrite + nitrate concentration) and the expression of endothelial‐type NO synthase (eNOS) were higher in mononuclear cells from ASA sensitive as compared with those from ASA‐resistant patients. There was a positive correlation between either the release of NO and the expression of eNOS protein in mononuclear cells with the ability of ASA to inhibit platelet activity. DBP content in mononuclear cells was higher in ASA resistant than in ASA sensitive. The level of DBP content in mononuclear cells was negatively associated with the ability of ASA to inhibit platelets. However, in vitro experiments suggested that there was no association between DBP and NO production by mononuclear cells.

Conclusions

Mononuclear cells from patients with platelets with lower responsiveness to ASA showed a reduced ability to produce NO.
Psychotherapy for adolescents and young adults at high risk for psychosis: a systematic review
Authors: Okuzawa Nana , Kline Emily , Fuertes Janine , Negi Shobhit , Reeves Gloria , Himelhoch Seth , Schiffman Jason
Published: February 2014

Aim

Unlike medication treatment, which may confer an unfavourable risk‐benefit ratio, psychosocial intervention has been an emerging target of recent randomized controlled trials (RCTs) assessing its efficacy in delaying or preventing the onset of psychosis in individuals identified at ‘clinical high risk’. Literature comparing qualitative differences in these psychotherapeutic interventions is scarce. The aim of the current study was to conduct a PRISMA systematic review evaluating the efficacy of psychotherapeutic interventions in reducing the rates of conversion to psychosis in clinical high‐risk individuals.

Methods

RCTs were identified in PubMed, Medline and PsycINFO databases up to 30 November 2013. Six studies (comprising 800 participants) met review inclusion criteria. Three investigators performed data extraction independently by using a pre‐structured selection form, and conducted risk of bias assessment employing the Cochrane approach.

Results

All six studies employed cognitive behaviour therapy as a core element. Three trials achieved a significant effect. The two trials that employed cognitive behaviour therapy enhanced for the specialized needs of clinical high‐risk patients maintained significant effects at post‐treatment follow up.

Conclusion

Evidence from recent trials suggest that cognitive behaviour therapy may be beneficial in delaying or preventing onset of psychosis in clinical high‐risk individuals, although effect sizes to date appear small. Further research is needed in larger samples to establish whether cognitive behaviour therapy is efficacious, and if additional intervention components can enhance established psychotherapies.
Vascular events after transsylvian selective amygdalohippocampectomy and impact on epilepsy outcome
Authors: Martens Tobias , Merkel Matthias , Holst Brigitte , Brückner Katja , Lindenau Matthias , Stodieck Stefan , Fiehler Jens , Westphal Manfred , Heese Oliver
Published: February 2014

Objective

Epilepsy surgery is a standard treatment option for medically intractable temporal lobe epilepsy. Selective amygdalohippocampectomy (SAH) and anterior temporal lobectomy (ATL) are two of the standard surgical procedures in these cases. We conducted a retrospective analysis of patients treated with SAH via a modified transsylvian approach in our epilepsy center between 2008 and 2011, and we analyzed the impact of adjacent procedure‐related infarctions on seizure outcome in these patients.

Methods

Infarctions were detected by magnetic resonance imaging (MRI) within the first week postoperatively and by a second MRI 9 months after surgical intervention. Neuropsychological testing was performed preoperatively. Evaluation of seizure outcome and postoperative neuropsychological testing were conducted approximately 1 year after epilepsy surgery. Correlative clinical data were analyzed by retrospective chart review.

Results

The postoperative MRI revealed temporal infarctions in 47.9% (n = 23/48) and frontal infarctions in 10.4% (n = 5/48) of the patients. These vascular events were asymptomatic in terms of focal neurologic deficits. Of the patients, 68.5% (n = 37/54) were free of disabling seizures (Engel class I) 1 year after the procedure. Patients with temporal infarctions were significantly more often free of disabling seizures (Engel class I, p = 0.046) than patients without temporal infarctions. Neuropsychological testing indicated a deterioration in verbal memory after SAH in patients with infarctions on the language‐lateralized hemisphere compared to patients without infarction (p = 0.011). All other tested neuropsychological categories showed no significant differences between patients with or without infarctions.

Significance

Our results indicate a surprisingly high number of procedure‐related temporal infarctions after transsylvian SAH. Hence, the volume of nonfunctional “eliminated” tissue is enlarged unintentionally, which is a possible explanation for better seizure outcome in these patients. This result supports the notion that ATL is the favorable procedure for temporal lobe epilepsy compared to SAH in the nondominant hemisphere, as neuropsychological deficits are rarely to be expected.

A PowerPoint slide summarizing this article is available for download in the Supporting Information section here.
Motor dual‐task Timed Up & Go test better identifies prefrailty individuals than single‐task Timed Up & Go test
Authors: Tang Pei‐Fang , Yang Hao‐Jan , Peng Ya‐Chi , Chen Hui‐Ya
Published: February 2014

Aim

The present study investigated whether dual‐task Timed Up & Go tests (TUG) could identify prefrail individuals more sensitively than the single‐task TUG (TUGsingle) in community‐dwelling middle‐aged and older adults.

Methods

This cross‐sectional study recruited adults aged 50 years and older who actively participated in local community programs. Time taken to complete single‐task TUG and dual‐task TUG, carrying a cup of water (TUGmanual) or carrying out serial‐3 subtraction (TUGcognitive) while executing TUG, was measured. Prefrailty status was defined based on Fried's phenotypic definition.

Results

Of the 65 participants (mean age 71.5 ± 8.1 years), 33.3% of the 12 middle‐aged (50–64 years) and 62.3% of the 53 older (≥65 years) adults were prefrail, mainly as a result of weak grip strength. The receiver operating characteristic curve analyses for differentiating prefrailty from non‐frailty showed that the area under the curve (AUC) for TUGmanual (0.73, 95% CI 0.60–0.86) was better than that for TUGsingle (0.67, 95% CI 0.54–0.80), whereas the AUC value was not significant for TUGcognitive (0.60, 95% CI 0.46–0.74). The optimal cut‐off points for detecting prefrailty using TUGsingle, TUGmanual and TUGcognitive were 7.7 s (sensitivity 68%), 8.2 s (sensitivity 83%), and 14.3 s (sensitivity 29%), respectively. After adjusting for age, logistic regression analyses showed that individuals with TUGmanual 8.2 s or slower were 7.2‐fold more likely to have prefrailty than those with TUGmanual faster than 8.2 s.

Conclusion

TUGmanual is more valid and sensitive than TUGsingle in identifying prefrail individuals. The TUGmanual thus could serve as a screening tool for early detection of individuals with prefrailty in community‐dwelling middle‐aged and older adults. Geriatr Gerontol Int 2015; 15: 204–210.
An Initial lexicon of sensory properties for nail polish
Authors: Sun C. , Koppel K. , Chambers E.
Published: February 2014

Synopsis

Objective

The objective of this study was to develop an initial lexicon for sensory properties of nail polish and to validate this lexicon using a descriptive analysis study of selected samples.

Methods

Seventeen commercial products from four categories (regular, flake‐containing, water‐based and gel) were used in this study. Descriptive sensory analysis was conducted in this study to characterize and evaluate application and removal properties of these nail polishes. Data was then processed by ANOVA, Principal Component Analysis (PCA) and Pearson's Correlation Coefficient analysis to explore the differences among samples and attributes.

Results

A lexicon of 21 sensory attributes was developed to describe the application of nail polish. It included three initial texture attributes, thirteen initial appearance attributes and five aroma attributes. A lexicon of five attributes in five stages was developed to describe the removal of nail polish. The results from ANOVA and PCA showed that attributes in the lexicon separated the different product categories.

Conclusion

The results of this study indicated that descriptive sensory analysis can be used to evaluate nail polish. The results of this study present scientists who are working on nail polish an additional tool to describe application and removal properties of nail polish.
‘Why nurses are leaving the profession … lack of support from managers’: What nurses from an e‐cohort study said
Authors: Tuckett Anthony , Winters‐Chang Peta , Bogossian Fiona , Wood Michael
Published: February 2014

The shortage of nurses is known. We explored nurses' reasons for leaving the profession based on responses from an e‐newsletter of theNurses andMidwives e‐cohortStudy. Qualitative content analysis of data from email responses (n = 66) showed ‘Lack of support’ as a social work value describing their manager's lack of support, unsupportive relationships within their work group, and a health‐care system putting business principles before care resulting in job dissatisfaction and nurse turnover. These findings are examples of a ‘complex'/‘wicked’ problem and as such will resist simple solutions to the presenting issues. The dialogic process such asOpenSpaceTechnology andTalkingCircles should be considered as potentially suitable to the needs of nurses.
Effects of Calcium Ions and of Calcium Channel Blockers on Galvanotaxis of Chlamydomonas reinhardtii
Authors: Dolle R. , Nultsch W.
Published: February 2014

The effects of calcium ions and of the calcium channel blockers verapamil, diltiazem and nifedipine on galvanotaxis in Chlamydomonas have been investigated using a fully automated and computerized population system. Galvanotaxis is a function of the voltage applied to the cell population. However, the galvanotactic orientation also depends on the external calcium concentration. In a calcium‐deprived nutrient medium which still contains 6 × 10−7M calcium, galvanotactic orientation is about 20% of orientation at optimal calcium concentration of 10−4 M at 9 V. The higher the external calcium concentration is, the lower is the voltage necessary for optimal galvanotactic orientation. The calcium channel blockers diltiazem and nifedipine likewise inhibit galvanotaxis of Chlamydomonas very specifically without impairing motility. Verapamil is effective, but also inhibits motility by causing detachment or shortening of the flagella. Nevertheless, inhibition of galvanotaxis by verapamil is not the only result of decreased motility, because the galvanotactic orientation is impaired to a greater extent than motility. The effectiveness of the three blockers tested in inhibiting galvanotaxis depends on the concentration and on the voltage applied. At 10−5 M, verapamil causes maximal inhibition of galvanotaxis at 9 V. At increasing concentrations up to 10−4 M, diltiazem inhibits galvanotaxis more strongly than the other blockers. If the voltage is varied at a constant blocker concentration of 2 × 10−5 M, nifedipine causes maximal inhibition at 3 V–6 V, diltiazem at 9 V and verapamil above 12 V.
Measurement of Light‐Dependent Changes of the Stromal pH in Wheat Leaf Protoplasts
Authors: Heineke D. , Heldt H. W.
Published: February 2014

The stromal pH of chloroplasts contained in wheat leaf protoplasts was determined by incubating the protoplast suspension with radioactively labelled DMO, followed by rapid subcellular fractionation and measurement of the radioactivity in the separated chloroplast fraction. The stromal pH was found to be about 8.0 upon illumination and 7.6 in darkness. These results demonstrate that light‐dependent stromal pH changes, which have been found earlier in isolated chloroplasts, also occur in a plant cell.
Evidence for Ideal and Non‐Ideal Equilibrium Freezing of Leaf Water in Frosthardy Ivy (Hedera helix) and Winter Barley (Hordeum vulgare)
Authors: Hansen J. , Beck E.
Published: February 2014

Temperature dependences of leaf water potentials (ψleaf) of frozen leaves of frosthardy ivy and winter barley were determined psychrometrically and found to coincide with the respective water potentials of ice which were obtained using the same technique. The water potentials of ice showed good agreement with theoretically established data. Analysis of the components of ψ of frozen leaves of Hedera helix revealed ideal equilibrium freezing, i.e. the governing of the relative content of liquid (or frozen) water solely by the osmotic potential. In winter barley, by contrast, a negative pressure potential was demonstrated to contribute to ψleaf. even under conditions of moderate frost. This reduced the degree of protoplast dehydration and the extent to which the concentrations of the cellular solutes rose. Such a freezing behavior is termed non‐ideal equilibrium freezing. Depending on the original content of leaf water, the volume increments of liquid water due to the negative pressure potential amounted up to 10% at −6 °C and even more at a lower temperature. In addition to the experimental data, a theoretical treatment of psychrometry at subzero temperatures is presented.
Euopsis and Harpidium, Genera of the Lichinaceae (Lichenes) with Rostrate Asci*
Authors: Henssen A. , Büdel B. , Titze A.
Published: February 2014

Based on corresponding ascocarp ontogeny and thallus structure, the genera Euopsis and Harpidium are included in the family Lichinaceae. In the two species of Euopsis, E. granatina and E. pulvinata, the apothecia develop from ascogonia in generative tissue, while in H. rutilans they are pycnoascocarps. In thallus anatomy, the species of Euopsis resemble Pyrenopsis haematopsis and allied species, while H. rutilans corresponds in structure and development of the thallus and apothecia to Pyrenopsis haemaleella (syn. P. sphinctotricha).

H. rutilans is the first member of Lichinaceae known to have only a green algal symbiont. In E. granatina, two phycobionts are always present, a species of Gloeocapsa and a chlorococcalean alga.

In Euopsis and Harpidium, the ascus wall is composed of an outer, non‐expansible and an inner, expansible layer; the latter surrounds the protoplast as an amyloid collar, which expands during spore release into a long, tapering rostrum. In Euopsis, the outer wall layer is strongly amyloid and the upper part separated from the expanded amyloid rostrum by a non‐amyloid zone, appearing like a slit in LM studies. The ultrastructure and function of the ascus in E. granatina has been studied in TEM and is interpreted as functionally unitunicate‐rostrate. Unitunicate asci with short rostrum are described for P. haemaleella and P. haematopsis.
In vitro Approach to Bacterial Chemotaxis
Authors: Eisenbach M. , Matsumura P.
Published: February 2014

An in vitro approach to study bacterial motility and chemotaxis is described. The approach is based on a preparation of flagellated cell envelopes. The envelopes are prepared from bacteria by a penicillin treatment and subsequent osmotic lysis. When the envelopes are energized, their flagella rotate. The direction of rotation in wild type envelopes is counterclockwise. Inclusion of the CheY protein within the envelopes may restore clockwise rotation. The advantages and disadvantages of this approach are pointed out.
Control of Ion Fluxes in Stomatal Guard Cells
Authors: MacRobbie E. A. C.
Published: February 2014

Opening and closing of the stomatal pore is associated with very large changes in K‐salt accumulation in stomatal guard cells. This review discusses the ionic relations of guard cells in relation to the general pattern of transport processes in plant cells, in plasmalemma and tonoplast, involving primary active transport of protons, proton‐linked secondary active transport, and a number of gated ion channels. The evidence available suggests that the initiation of stomatal opening is regulated through the uptake mechanisms, whereas initiation of stomatal closing is regulated by control of ion efflux at the plasmalemma, and of fluxes to and from the vacuole. In response to a closing signal there are large transient increases in efflux of both Cl− (or Br−) and Rb+ (K+) at the plasmalemma, with also a probable increase in anion flux from vacuole to cytoplasm and decrease in anion flux from cytoplasm to vacuole. A speculative hypothetical sequence of events is discussed, by which the primary response to a closing signal is an increase in Ca2+ influx at the plasmalemma, producing depolarisation and increase in cytoplasmic Ca2+. The consequent opening of Ca2+‐sensitive Cl− channels, and voltage‐sensitive K+ channels (also Ca2+‐sensitive?) in the plasmalemma, and of a Ca2+‐sensitive nonspecific channel in the tonoplast, could produce the flux effects identified by the tracer work; this speculation is also consistent with the Ca2+‐sensitivity of the response to closing signals and with evidence from patch clamping that such channels exist in at least some plant cells, though not yet all shown in guard cells.
Developmental Physiology Apparent Dark Decay of Phytochrome Pfr in Fern Spores
Authors: Haupt W. , Filler E.
Published: February 2014

Germination of spores of Dryopteris fllix‐mas has been induced by two pulses of saturating red light, separated by a dark period of about 8 to 24 h. By chosing different wavelengths, different Pfr/Ptot levels could be established. Thus, by a “null method” the second pulse could be used as a “test pulse”, determining the actual Pfr level remaining from the “start pulse”, and thus providing information about an apparent Pfr decay. It cannot be decided yet whether this apparent Pfr decay results from dark destruction or dark reversion.

The apparent Pfr decay depends, as expected, on the temperature, being accelerated with increasing temperatures. Moreover, the later after sowing that the decay is tested, the faster it proceeds; a tentative interpretion is that newly synthesized Pr undergoes faster decay after phototransformation than that phytochrome pool present in the resting spores. A third factor that influences the apparent Pfr decay is the Pfr/Ptot level established by the first pulse (start pulse). The lower this level, the slower the decay kinetics. This could be due to phytochrome biosynthesis partly compensating for Pfr destruction, and the relative contribution of this biosynthesis to the total effect increases with lower Pfr levels. Spores of D. paleacea yield virtually the same results.

Whatever the real basis of the observed Pfr decay, i.e. destruction, reversion, or a combination of these reactions with biosynthesis, it can be concluded that modification of this Pfr decay by various factors is the basis of the effect of those factors on light‐induced germination.
Characterization of the Vacuolar Proton Pumps of the Cortex, Stele and Tip of Maize Roots: Effects of Salinity
Authors: Walker K. E. , Taiz L.
Published: February 2014

Tonoplast and Golgi ATP‐driven proton pumping was measured in membrane vesicles isolated from the cortex, stele and tip of maize roots. Two nitrate‐sensitive peaks of tonoplast proton pumping were detected on sucrose gradients, a light peak at 16% sucrose, believed to represent small vacuoles, and a denser peak at 25% sucrose, possibly derived from large vacuoles. The nitrate‐insensitive Golgi peak occurred at 31 % sucrose. Membrane preparations of the stele and tip were active in H+‐transport activity and were rich in mitochondria. In contrast, the membranes of the cortex had low levels of both ATP‐driven proton pumping and mitochondrial activities. Salinity caused a doubling of the tonoplast H+‐transport activity of the tip and cortex, particularly in the 25 % sucrose peak. The enhancement of the 25 % peak by salinity was correlated with an increase in vacuolation of the tip. The stelar proton pumps were only slightly stimulated by salinity. The results indicate that the cortex of maize roots is deficient in the metabolic machinery needed for vacuolar solute accumulation, but that it shows some ability to adapt to saline conditions. The physiological implications of these findings are discussed.
Quantum Requirements of Photosynthetic Oxygen Evolution and 77 K Fluorescence Emission Spectra in Unicellular Green Algae Grown Under Low‐ and High‐CO2‐Conditions
Authors: Burger J. , Miyachi S. , Galland P. , Senger H.
Published: February 2014

Quantum requirements of photosynthetic oxygen evolution at 682 nm and fluorescence spectra at liquid nitrogen temperature (77 K), were investigated in Dunaliella tertiolecta, Chlamydomonas reinhardtii C‐9, Chlorella vulgaris 11g, Chlorella vulgaris C3, and Chlorella pyrenoidosa 8b grown under low‐ and high‐CO2 conditions. Dunaliella, Chlamydomonas and C. vulgaris 11g show higher quantum requirements and a higher ratio of F710–740/F680–695 fluorescence when grown under low‐CO2 conditions, indicating a change in excitation energy distribution towards PS I. In C. pyrenoidosa the quantum requirement for low‐CO2 grown cells is higher than in high‐CO2 grown cells, but there was practically no change in the fluorescence ratio. In C. vulgaris C3, the quantum requirements of low‐ and high‐CO2 grown cells are the same, but the fluorescence ratio is higher in high‐CO2 grown cells than in low‐CO2 grown cells. These results indicate that most of the low‐CO2 grown cells require more PS I light than high‐CO2 grown cells. It is possible that this energy is used for cyclic electron flow. In C. vulgaris C 3, a mechanism may exist for excitation energy distribution which leads to the same quantum requirements under low‐ and high‐CO2 conditions.
Protoplast Culture in Agarose Media with Particular Emphasis to Streaky Culture Lenses*
Authors: Binding H. , Görschen E. , Jörgensen J. , Krumbiegel‐Schroeren G. , Ling H. Q. , Rudnick J. , Sauer A. , Zuba M. , Mordhorst G.
Published: February 2014

Isolated protoplasts of 60 species of the Magnoliatae and 19 species of the Liliatae were embedded in droplets of agarose‐containing media in such a way that streaks of locally high cell densities were obtained. For comparison, agarose cultures with dispersed protoplasts and liquid cultures were prepared. Fast and reliable regeneration was obtained in several taxa. After transfer to low osmolar media, shoots were formed in 18 species belonging to the genera Arabidopsis, Asparagus, Biscutella, Brassica, Cichorium, Clianthus, Hypericum, Nicotiana, Petunia, Reseda, Senecio, and Solanum. Only protoplast‐derived callus which did not organize shoots was grown in species of Agrimonia, Daucus, Cucumis, Duchesnea, Helianthus, Potentilla, Prunus, Reseda, Solanum, Sorbus, Spinacia, and Vicia.
Cells with Crystals of Calcium Oxalate in the Leaves of Phaseolus vulgaris — a Comparison with those in Canavalia ensiformis
Authors: Zindler‐Frank E. , Wichmann E. , Korneli M.
Published: February 2014

Leaflets of Phaseolus vulgaris contain crystals of calcium oxalate in the adaxial bundle sheath extensions. Most of the crystals accompany the lateral veins of third order. The average oxalate content of the leaves is 0.8% of dry weight. Some features of leaflet anatomy of Phaseolus and Canavalia are shown and the possible relation of anatomy to localization and development of crystals in each of the species is discussed. The majority of crystals in Phaseolus originate with the young leaflets newly unfolded. Calcium deficiency reduces number and size of crystals.
Cadmium‐Induced Structural and Ultrastructural Changes in the Vascular System of Bush Bean Stems
Authors: Barceló J. , Vázquez M. D. , Poschenrieder Ch.
Published: February 2014

The effects of a phytotoxic cadmium concentration (4.45 . 10−5 M) on the structure and ultrastructure of bean plant stems were analysed by light (LM), transmission electron (TEM) and scanning electron microscopy (SEM). Cadmium significantly reduced both the number and the size of tracheary elements. Cadmium‐induced electron dense depositions, which seemed to obstruct partially some xylem vessels, were found only in the later maturing tracheary elements (helical, scalariform or reticulate structure), but not in the annular structured early differentiated ones. Plants exposed to Cd showed less fiber development than the control plants. In the plants treated with Cd abnormally high amounts of calcium oxalate crystals were found in the paratracheary parenchyma cells of the bottom of the stems. The levels of soluble Ca2+ in the expressed stem sap of Cd‐treated plants was significantly decreased, while substantial amounts of soluble Cd were detected. The probable mechanisms of the structural alterations observed are discussed.
Biophysical Examinations of the Bending Stability of Various Stele Types and the Upright Axes of Early “Vascular” Land Plants
Authors: Speck Dipl. ‐Biol. T. , Vogellehner D.
Published: February 2014

Biophysical methods allow quantitative deductions as to the “bending effectivity” of various stele types and the contribution of different tissues to the stability of upright plant axes. Considering the first occurrence of the different stele types in geological history, a strong tendency towards a higher “bending effectivity” can be observed. It can be shown that Rhynia gwynne‐vaughanii, Aglaophyton major (Rhynia major) and Asteroxylon mackiei as well as probably the vast majority of early “vascular” land plants were turgor systems, i.e. that the parenchyma (when fully turgescent) is by far the most important contributory factor towards the bending stability of the upright axes.
Nuclear Degeneration during Ballistospore Formation of Cronartium asclepiadeum (Uredinales)*
Authors: Bauer R. , Oberwinkler F.
Published: February 2014

When basidia of Cronartium asclepiadeum (Uredinales) develop basidiospores, nuclei migrate from the basidial cells into the basidiospores. A mitotic nuclear division yields two nuclei in the basidiospore. One of these nuclei degenerates if the basidiospore develops a secondary ballistospore. Several stages in the degeneration of the nuclei can be recognized: (1) Condensation of chromatin, (2) separation of the nucleus into a portion containing the chromatin and a portion containing the nucleoplasm by an invagination of the nuclear envelope, (3) reduction of nuclear volume, (4) enveloping and (5) twisting of nuclear membranes around the degenerating nucleus, (6) homogenization of the chromatin with reduction of the nuclear envelope, and reduction of the enclosing membrane complex from a multilamellar structure to a single membrane layer, and (7) invagination or splitting off of the spiralled membranes. The nuclear behavior during early developmental stages of secondary spore formation is similar to that of budding basidiomycetous yeasts. Basidiomycetes producing ballistospores may possibly have arisen from those whose reproducing phase is yeast‐like.
Cytokinin, Light, and “Developmental Control” of Protein Synthesis in Cucurbita Cotyledons
Authors: Le Silva , Le W. , Wollgiehn R. , Parthier B.
Published: February 2014

Cotyledons detached from pumpkin seedlings of different stages of development were either illuminated or treated with 4.10−5 M cytokinin (benzyladenine, BA) in darkness. Comparison of the abilities to incorporate 14C‐leucine into proteins in vivo as well as 35S‐methionine in vitro by means of an RNA‐programmed cell‐free wheat germ system demonstrates that the patterns of the two‐dimensionally separated in vivo labelled soluble proteins are very similar in differently developed or treated cotyledons. Although the translatable mRNA patterns were almost identical in qualitative respect, our data do not exclude the appearance of a few minor polypeptides altered by either illumination or BA treatment. The steady‐state levels of the mRNAs in cotyledons from 12 days old seedlings were remarkably similar irrespective of cotyledon treatment (water, BA, light) and resemble those levels obtained with illuminated or BA‐treated cotyledons of earlier seedlings stages. Our results suggest that the amount of abundant (soluble) proteins in pumpkin cotyledons is developmentally regulated mainly at the transcript level. Extrinsic factors such as cytokinins (BA) or light are equally able to accelerate the developmental program of gene expression in early‐detached cotyledons, which are probably deficient in endogenous hormone.
Accumulation of Storage Materials, Precocious Germination and Development of Desiccation Tolerance During Seed Maturation in Mustard (Sinapis alba L.)
Authors: Fisc W. , Bergf R. , Pla C. , Schäfer R. , Schopfer P.
Published: February 2014

Under defined environmental conditions (20°C, continuous light of 15 klx) development of mustard seeds from artificial pollination to maturity takes about 60 d. After surpassing the period of embryo cell division and histodifferentiation (12–14d after pollination = dap), the seed enters into a maturation period. The time courses of various physiological, biochemical, and structural changes of embryo and testa during seed maturation were analyzed in detail (dry and fresh mass changes, osmotic and water potential changes, respiration, DNA amplification by endomitosis, total ribosome and polysome formation, storage protein synthesis and accumulation, storage lipid accumulation). In addition to the final storage products protein and lipid, embryo and testa accumulate transiently large amounts of starch within the chloroplasts during early maturation. Concomitantly with the subsequent total breakdown of the starch, the plastids lose most of their internal structure and chlorophyll and shrink into proplastids, typical for the mature seed. At about 30 dap the seeds shift from a desiccation‐sensitive to a desiccation‐tolerant state and are able then to germinate rapidly upon drying and reimbibition. If isolated from the immature fruit and sown directly on water, the seeds demonstrate precocious germination from about 13 dap onwards. Young seeds (isolated ≦ 38 dap) germinate only after surpassing a lag‐phase of several days (after‐ripening) during which the embryo continues to accumulate storage protein and lipid at the expense of the surrounding seed tissues. We conclude from these results that the maturing seed represents a rather closed developmental system which is able to continue its development up to successful germination without any specific regulatory influence from the mother plant. Immature seeds are able to germinate without a preceding dehydration treatment, which means that partial or full desiccation does not serve as an environmental signal for reprogramming seed development from maturation to germination. Instead, it is argued that the water relations of the seed are a critical element in the control of maturation and germination: during maturation on the mother plant the embryo is subject to a considerable turgor pressure (of the order of 12 bar) accompanied by a low water potential (of the order of −12 bar). This turgor permits maturation growth but is subcritical for germination growth. However, upon imbibition in water, the low water potential provides a driving force for a burst of water uptake overcoming the critical turgor threshold and thereby inducing germination.
Morphogenetic and Histological Events during Somatic Embryogenesis in Intact Carrot Plantlets (Daucus carota L.) in Various Nutrient Media
Authors: Schä F. , Grieb B. , Neumann K.‐H.
Published: February 2014

It is shown that the induction of somatic embryogenesis neither requires the isolation of explants from intact carrot plants nor mechanical or chemical “wounding”.
Breakdown of Galactolipids in Senescent Barly Leaves
Authors: Gut Hans , Matile Philippe
Published: February 2014

The changes of galactolipids (MGDG and DGDG, largely 18:3/18:3), free fatty acids (FFA), and phosphatidylcholine (PC) taking place during senescence of primary barley leaves were analysed employing HPLC and GLC. Upon induction of senescence MGDG and, with some delay, DGDG began to disappear and were largely broken down at the end of the senescence period. A concomitant appearance of a pool of FFA could not be observed. However, PC accumulated during the main period of galactolipid breakdown. This change was due to the marked increase of the 18:3/18:3 molecular species of PC. An inverse correlation between the changes of galactolipids and PC could be established. A hypothesis featuring the conversion of galactolipids via diacylglycerol to PC is presented as the principal route of galactolipid breakdown.
Immunocytochemical Localization of Phycoerythrin‐545 and of a Chlorophyll a/c Light Harvesting Complex inCryptomonas maculata(Cryptophyceae)
Authors: Rhiel E. , Kunz J. , Wehrmeyer W.
Published: February 2014

Antisera, raised against the subunits of phycoerythrin‐545 and total chlorophyll a/c light harvesting complex (chl a/c LHC) ofCryptomonas maculata, were tested for specificity by immunodiffusion and Western‐immunoblotting experiments. They were further used for immunogold‐labeling of Lowicryl sections of control and nitrogen deficient cells. In control cells (+ N) the antiserum against the chl a/c LHC labeled the thylakoid membranes uniformly. On the other hand, the label against the subunits of the water soluble phycoerythrin‐545 was almost completely restricted to the thylakoid lumen. Nitrogen deficient cells (–N) compared to control cells exhibited labels against the chl a/c LHC with very similar densities per unit area. For the subunits of phycoerythrin‐545 a three‐ to four‐fold weaker gold label per unit area was measured. These results confirm some of the earlier conclusions, e.g. the persistence of the chl a/c LHC even under conditions of nitrogen‐deficiency and the extensive degradation of the biliprotein (Rhiel et al., 1985, 1986, 1987).
Immunofluorescent Staining of Microtubules in Plant Tissues: Improved Embedding and Sectioning Techniques using Polyethylene Glycol (PEG) and Steedman's Wax
Authors: Brown R. C. , Lemmon B. E. , Mullinax J. B.
Published: February 2014

Methods for the indirect immunofluorescent staining of microtubules in embedded and sectioned plant tissues are described and compared. Root tips of Vicia faba, Saccharum officinale, Allium cepa, and root nodules of Glycine max were fixed using conventional methods, embedded in polyethylene glycol or Steedman's wax, sectioned with a glass knife on a rotary microtome, and dewaxed in water or alcohol. The addition of dithiothreitol (DTT), dehydrating at low temperatures and reducing the infiltrations times were found to reduce background fluorescence in Allium cepa. Steedman's wax yields a block that is similar to paraffin and is easier to section than PEG. Routine methods for indirect immunofluorescence were used to stain sections for tubulin/microtubules. The major microtubule arrays of mitotic cells are illustrated in this paper. The principal advantage of this technique is the preservation of cell‐to‐cell continuity in multicellular tissues. This method provides a much needed technique for the study of the cytoskeleton during growth and differentiation of plant tissues.
Immunological Characterization of Gamete Autolysins in Chlamydomonas reinhardtii
Authors: Waffenschm Sabine , Kuhne Dipl.‐Biol. Wolfgang , Jaenicke Lothar
Published: February 2014

Polyclonal antibodies were raised in rabbits against the C. reinhardtii cell wall lytic enzyme, autolysin, which dissolves the cell wall of gametes prior to cell fusion. The purified immunoglobulins react with both the native and the deglycosylated forms of this gametic autolysin and specifically inhibit enzyme activity. In addition, the immunoglobulins selectively detect the gametic autolysin in immunoblots of crude extracts and do not cross‐react with the autolysin of the vegetative cells. The antibodies have been used to study the time of synthesis of the enzyme during gametogenesis and to compare gametic autolysins of different strains of Chlamydomonas.
The Osmometer Model of the Root: Water and Solute Relations of Roots of Phaseolus coccineus
Authors: Steudle E. , Brinckmann E.
Published: February 2014

Water and solute relations of young roots of Phaseolus coccineus have been measured using the root pressure probe. Biphasic root pressure relaxations were obtained when roots were treated with solutions containing different osmotic test solutes. From the relaxations, the hydraulic conductivity (Lpr), the permeability coefficient (Psr), and the reflection coefficient (σsr) of the roots could be evaluated. Lpr was 1.8 to 8.4 . 10−8 m . s−1 . MPa−1 and Psr (in 10−10 m . s−1): methanol, 27–62; ethanol, 44–73; urea, 5–11; mannitol, 1.5; KCl, 7.1–9.2; NaCl, 2.1; NaNO3, 3.7. The hydraulic conductivity was similar when using osmotic and hydrostatic pressure gradients as driving forces. The hydraulic conductivity of individual root cortex cells (Lp) was by two orders of magnitude larger than Lpr (Lp = 0.3 to 4.7 . 10−6 m . s−1 . MPa−1) which indicated a predominant cell‐to‐cell rather than an apoplasmic transport of water in the Phaseolus root. Except for distances shorter than 20 mm from the root apex, the hydraulic resistance of the roots was limited by the radial movement of water across the root cylinder and not by the hydraulic resistance within the xylem. Reflection coefficients were low: methanol: 0.16–0.34; ethanol: 0.15–0.47; urea: 0.41–0.51; mannitol: 0.68; KCl: 0.43–0.54; NaCl: 0.59; NaNO3: 0.54. The transport coefficients (Lpr, Psr, σsr) have been critically examined for influences of unstirred layers and active transport. The low σsr suggests that the common treatment of the root as a rather perfect osmometer (σsr = 1) analogous to plant cells should be treated cautiously. The reasons for the low σsr and the possible implications of the absolute values of the transport parameters for the absorption of water and nutrients are discussed.
Ultrastructural and Morphological Characteristics of Cultivated Wheat Growing on Copper‐Polluted Fields
Authors: Eleftheriou Ass. Prof. Dr. E. P. , Karataglis S.
Published: February 2014

A cultivated Greek variety of wheat (Triticum aestivum L. cv. Vergina) growing in fields naturally polluted by outcrops of copper ores was investigated. Wheat plants show a negative response to increasing quantities of soil copper, including reduced growth and chlorosis. Copper toxicity was demonstrated in the laboratory by a rooting test; the frequency of mitoses declines sharply with increasing copper concentration in the nutrient solution.

The mesophyll cells of polluted plants display a circular shape (in transverse sections) with a few chloroplasts parietally distributed, in contrast with the elongate or pleomorphic shape of control leaves that contain numerous chloroplasts crowded at the cell periphery. Ultrastructurally, the chloroplasts of polluted plants contain a poorly developed internal membrane system consisting of thylakoids arranged parallel to each other with only a few, rudimentary grana. In addition, a number of statistically significant differences were found, including the number of starch grains and plastoglobuli, chloroplast surface area, volume fraction of starch grains and, most important, the volume fraction of the internal membrane system. All ultrastructural changes are attributed to the toxic effect of high concentrations of soil copper.
A Comparative Ultrastructural Investigation of Some Nannochloris Species (Chlorococcales) with Particular Reference to the Systematic Position of Nanochlorum eucaryotum
Authors: Menzel Karola , Wild Aloysius
Published: February 2014

Nanochlorum eucaryotum was described by Wilhelm et al. (1982) as a new algal species with an uncertain taxonomic position. Whereas some features were chlorococcacean, others suggested an isolated position in the sense of a “pre‐eucaryote” (Wilhelm, 1983; Zahn, 1984; Geisert et al., 1987). Our comparative ultrastructural, physiological and biochemical examinations of coccoid microalgae (Menzel, 1988) gave no arguments for the separation of Nanochlorum eucaryotum from the genus Nannochloris. This paper is concerned with the ultrastructural composition of the cell wall and mode of reproduction in Nanochlorum eucaryotum as well as in three Nannochloris species. The systematic position of Nanochlorum eucaryotum is discussed in comparison with representatives of the genus Nannochloris. As a result, Nanochlorum eucaryotum has been included in the genus Nannochloris.
Chaotic Floral Phyllotaxis and Reduced Perianth in Achlys (Berberidaceae)
Authors: Endress Peter K.
Published: February 2014

Among the 16 genera of the Berberidaceae Achlys is the only one with a reduced perianth, an irregular floral phyllotaxis, and variable stamen number. Early floral stages show an unstable (chaotic) arrangement of the organ primordia. Only the single carpel of the gynoecium has a more fixed position in that the placenta is formed in the adaxial half of the flower. The irregularities in the androecium may be caused by the lack of influence of a perianth on floral symmetry. On the other hand, the regular orientation of the carpel is perhaps due to the early polarity of the flower, whereby the abaxial half of the flower is larger (with further developed stamen primordia) at the time when carpel polarity is established.