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Halophytes are potential gene sources for genetic manipulation of economically important crop species. This study addresses the physiological responses of a widespread halophyte, Prosopis strombulifera ( Lam.) Benth to salinity. We hypothesised that increasing concentrations of the two major salts present in soils of central Argentina ( Na2SO4, NaCl, or their iso-osmotic mixture) would produce distinct physiological responses. We used hydroponically grown P. strombulifera to test this hypothesis, analysing growth parameters, water relations, photosynthetic pigments, cations and anions. These plants showed a halophytic response to NaCl, but strong general inhibition of growth in response to iso-osmotic solutions containing Na2SO4. The explanation for the adaptive success of P. strombulifera in high NaCl conditions seems to be related to a delicate balance between Na + accumulation (and its use for osmotic adjustment) and efficient compartmentalisation in vacuoles, the ability of the whole plant to ensure sufficient K+ supply by maintaining high K +/ Na + discrimination, and maintenance of normal Ca2 + levels in leaves. The three salt treatments had different effects on the accumulation of ions. Findings in bi-saline-treated plants were of particular interest, where most of the physiological parameters studied showed partial alleviation of SO42−-induced toxicity by Cl−. Thus, discussions on physiological responses to salinity could be further expanded in a way that more closely mimics natural salt environments. [ABSTRACT FROM AUTHOR]

Introduction: Type 2 Diabetes Mellitus is a serious health problem. In the year 2030 it will affect 366 million people around the world. Objective: Evaluate the effectiveness of a mixed intervention and reducing the amount and seriousness of acute complications in diabetics from our Health Area. Materials and method: Protocols of action as well as information documents were produced. Diabetes Unit coordinated educational activities in the different support levels of the Area VII of Murcia. Information talks were provided for the people in charge of the Diabetes Unit in every Care Center and Service of the Health Area. Personalized training was provided for patients treated in the differet Care levels. The study comprised three stages. Information leaflets were spread and talks offered to the patient regarding in house handling of hypo and hyper glycemia. Results: A reduction of 39% of the emergencies due to acute non complicated diabetes was achieved, as well as a reduction of 47.6% of hospital admissions. There was a reduction of 67.8% of the amount of total hospital stays for the group of patients under 35 years who were admitted into the hospital due to type 1 or 2 diabetes mellitus that didn't show any complications (GRD295). Conclusions: There was a reduction of more than thirty percent in the emergencies due to acute decompensations in the disease and a significant reduction in the avoidable hospital stays in the young adult, thus improving the patients' life quality and reducing the social cost of the diabetic patient. [ABSTRACT FROM AUTHOR]

Introduction: Type 2 Diabetes Mellitus is a serious health problem. In the year 2030 it will affect 366 million people around the world. Objective: Evaluate the effectiveness of a mixed intervention and reducing the amount and seriousness of acute complications in diabetics from our Health Area. Materials and method: Protocols of action as well as information documents were produced. Diabetes Unit coordinated educational activities in the different support levels of the Area VII of Murcia. Information talks were provided for the people in charge of the Diabetes Unit in every Care Center and Service of the Health Area. Personalized training was provided for patients treated in the differet Care levels. The study comprised three stages. Information leaflets were spread and talks offered to the patient regarding in house handling of hypo and hyper glycemia. Results: A reduction of 39% of the emergencies due to acute non complicated diabetes was achieved, as well as a reduction of 47.6% of hospital admissions. There was a reduction of 67.8% of the amount of total hospital stays for the group of patients under 35 years who were admitted into the hospital due to type 1 or 2 diabetes mellitus that didn't show any complications (GRD295). Conclusions: There was a reduction of more than thirty percent in the emergencies due to acute decompensations in the disease and a significant reduction in the avoidable hospital stays in the young adult, thus improving the patients' life quality and reducing the social cost of the diabetic patient. [ABSTRACT FROM AUTHOR]

Background: Human papillomavirus (HPV) infection is the most common sexually transmitted infection in the United States. High-risk HPV strains are associated with cancer of the cervix, oropharynx, anus, rectum, penis, vagina, and vulva. To combat increasing HPV-related cancers, the 9-valent HPV vaccine Gardasil was developed. Recommendation of the HPV vaccine by a health care provider has been cited as the number one factor affecting vaccine uptake among adolescents and young adults. Physician assistants, nurse practitioners, and pharmacists have been enlisted to bridge the gap., Objective: The specific aim of this research study was to develop a reliable and valid HPV vaccine communication scale that can be used to measure the competency of primary care providers when recommending the need for vaccination to parents and patients., Methods: Using a descriptive study, we collected data via a literature review, focus groups, and an expert panel to inform the scale domains and blueprint design. Pretesting (cognitive interviews) was used to inform item revision decisions. An item analysis was also conducted for the responses provided in the cognitive interviews. Item statistics (means and SDs), interitem correlations, and reliability were examined. Data were analyzed using SPSS (IBM Corp) software., Results: A valid and reliable 42-item HPV vaccine communication competency scale was developed. The scale included 6 domains of interest. Scale items were moderately to strongly correlated with one another, and Cronbach α indicated good internal consistency with each scale. Scale items included were related to provider introduction or rapport (α=.796), patient respect or empathy (α=.737), provider interview or intake (α=.9), patient counseling or education (α=.935), provider communication closure (α=.896), and provider knowledge (α=.824)., Conclusions: Pharmacists, nurse practitioners, and physician assistants should be trained to be competent in HPV vaccine communication and recommendation due to their expanded roles. Interdisciplinary collaboration is important to account for the trainee's individual differences and ensure the best health care outcomes for patients. A standardized HPV communication scale can be used to ensure effective and consistent recommendation by health care providers, thus affecting immunization rates., (©Gabrielle Darville-Sanders, Humberto Reinoso, Jann MacInnes, Emilie Corluyan, Dominique Munroe, Mary W Mathis, Suzie Lamarca Madden, Johnathan Hamrick, Lisa Dickerson, Cheryl Gaddis. Originally published in JMIR Formative Research (https://formative.jmir.org), 04.11.2022.)

Background and Purpose: The purpose of this study was to evaluate Mishel Uncertainty in Illness Scale-Community (MUIS-C), used to gauge level of uncertainty among baby boomers with hepatitis C virus (HCV) infection, as a reliable two-factor instrument., Methods: A CFA was conducted to test MUIS-C. There were minor deviations from normality. Subsequently, 130 participants were used to examine the factor structure and the model fit. A robust maximum likelihood (ML) estimation using the Wishart distribution was implemented in R version 3.3.1., Results: A very good model fit was obtained ( χ 2 (101) = 118.32, p = .115, TLI = 0.977, CFI = 0.983, RMSEA = 0.036, 90% CI (0.000, 0.061), and SRMR = 0.057). All indicators showed significant positive factor loadings, with standardized coefficients ranging from 0.511 to 0.868., Conclusions: The MUIS-C was a reliable two-factor instrument and suitable for use as such in baby boomer population with HCV., (© Copyright 2021 Springer Publishing Company, LLC.)

An aging population benefits from healthcare providers trained in the care of older adults. Interprofessional education (IPE) and service-learning activities focused on geriatric conditions like falls may address this need. A fall prevention IPE activity using the Centers for Disease Control and Prevention (Stopping Elderly Accidents, Deaths & Injuries (STEADI) initiative was implemented to prepare health sciences students to manage older adult falls. Students (N = 31) and faculty (N = 10) from five health sciences programs and local older adults (N = 27) participated. Students were trained in STEADI and conducted a fall risk screening, assessment, and intervention activity with older adults using STEADI tools. We observed a statistically significant improvement in student knowledge of fall prevention and STEADI as assessed by pre and postactivity measures. Student surveys indicated improved understanding of the roles and responsibilities of participating disciplines, related to management of falls in older adults. The CDC's STEADI initiative may provide an effective framework and resources for fall prevention IPE activities and geriatric health sciences education.

In semi-arid regions, plants develop various biochemical and physiological strategies to adapt to dry periods. Understanding the resistance mechanisms to dry periods under field conditions is an important topic in ecology. Larrea divaricata and Lycium chilense provide various ecological services. The aim of this work is to elucidate new morpho-histological, biochemical and hormonal traits that contribute to the drought resistance strategies of two native shrubs. Green leaves and fine roots from L. divaricata and L. chilense were collected in each season for one year, and various traits were measured. The hormone (abscisic acid, ABA-glucose ester, gibberellins A 1 and A 3 , and indole acetic acid) contents were determined by liquid chromatography coupled to mass spectrometry. Rainfall data and the soil water content were also measured. A multivariate analysis showed that green leaves from L. divaricata showed high values for the leaf dry weight, blade leaf thickness and ABA content in the summer compared with those from L. chilense. Fine roots from L. divaricata had high RWC and high IAA levels during the autumn-dry period compared with those from L. chilense, but both had similar levels during the winter and spring. Our results support the notion that species with different drought resistance mechanisms (avoidance or tolerance) display different responses to dry periods throughout the year. Larrea divaricata, which exhibits more xerophytic traits, modified its morphology and maintained its physiological parameters (high RWC in leaves and roots, high ABA levels in leaves during summer, high GA 3 in leaves and high IAA in roots during autumn) to tolerate dry periods, whereas Lycium chilense, which displays more mesophytic traits, uses strategies to avoid dry periods (loss of leaves during autumn and winter, high RWC in leaves, high ABA-GE and GA 3 in leaves during summer, high GA 1 and GA 3 in roots during summer, and high IAA in roots during autumn and summer) and thus has a metabolism that is more dependent on water availability for growth., (Copyright © 2018. Published by Elsevier Masson SAS.)

One fourth of all American's over 65 years of age fall each year. Falls are a common and often devastating event that can pose a serious health risk for older adults. Healthcare providers are often unable to spend the time required to assist older adults with fall risk issues. Without a team approach to fall prevention the system remains focused on fragmented levels of health promotion and risk prevention. The specific aim of this project was to engage older adults from the community in a fall risk assessment program, using the Stopping Elderly Accidents, Deaths & Injuries (STEADI) program, and provide feedback on individual participants' risks that participants could share with their primary care physician. Older adults who attended the risk screening were taking medications that are known to increase falls. They mentioned that their health care providers do not screen for falls and appreciated a community based screening., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Advanced Practice Holistic Nurse (APHN) leaders could provide a model of leadership to advance value based health care systems in the United States. The American Nurses Association has recognized Holistic Nursing as a specialty because of the emphasis placed on patient-centered care, the development of therapeutic relationships, interconnection, and holism. Transformational leadership is a framework that uses vision, inspiration and intellectual stimulation to motivate people toward needed change. The APHN is well positioned to use transformational leadership methods to lead teams placing the patient at the center of health care decision making and bring the essence of holism to the forefront of health care. Highlighted are methods for positive communication, inspiration, negotiation, and conflict resolution as tools the APHN could use to become a transformational leader. The purpose of this article is to discuss a framework for transformational leadership development and implementation to establish the holistic ideals of APHNs in the health care system.

Background: Baby boomers account for two out of every three cases of hepatitis C infection in the U.S., Purpose: To conduct an exploratory factor analysis directed at supporting the use of the MUIS-C as a reliable instrument in measuring illness uncertainty among baby boomers with hepatitis C., Methods: The steps of conducting a typical principal component analysis (PCA) with an oblique rotation were used on a sample of 146 participants, the sampling adequacy of items was examined via the Kaiser-Meyer-Olkin (KMO) measure, and the Bartlett's sphericity test was used for appropriateness of conducting a factor analysis., Results: A two-factor structure was obtained by using Horn's parallel analysis method. The two factors explained a cumulative total of 45.8% of the variance., Conclusions: The results of the analyses indicated that the MUIS-C was a valid and reliable instrument and potentially suitable for use in baby boomer population diagnosed with hepatitis C., (Published by Elsevier Inc.)

Soybean (Glycine max) is often exposed to high arsenic (As) level in soils or through irrigation with groundwater. In previous studies on As-treated soybean seedlings we showed deleterious effect on growth, structural alterations mainly in root vascular system and induction of antioxidant enzymes. However, there are not reports concerning signal transduction pathways triggered by the metalloid in order to develop adaptive mechanisms. Phosphatidic acid (PA), a key messenger in plants, can be generated via phospholipase D (PLD) or via phospholipase C (PLC) coupled to diacylglycerol kinase (DGK). Thus, changes in PA and in an enzyme involved in its metabolism (PLD) were analysed in soybean seedlings treated with 25 μM AsV or AsIII. The present study demonstrated that As triggers the PA signal by PLD and also via PLC/DGK mainly after 48 h of As treatment. DGPP, other lipid messenger produced by phosphorylation of PA by PAK increased in As treated roots. Arsenic also induced rapid and significant stomatal closure after 1.5 h of treatment, mainly with AsIII, probably as an adaptive response to the metalloid to reduce water loss by transpiration. This report constitute the first evidence that shows the effects of As on lipid signalling events in soybean seedlings which would be crucial in adaptation and survival of soybean seedlings under As stress., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

Grape quality for winemaking depends on sugar accumulation and metabolism in berries. Abscisic acid (ABA) and gibberellins (GAs) have been reported to control sugar allocation in economically important crops, although the mechanisms involved are still unknown. The present study tested if ABA and gibberellin A3 (GA3) enhance carbon allocation in fruits of grapevines by modifying phloem loading, phloem area and expression of sugar transporters in leaves and berries. Pot-grown Vitis vinifera cv. Malbec plants were sprayed with ABA and GA3 solutions. The amount of soluble sugars in leaves and berries related to photosynthesis were examined at three points of berry growth: pre-veraison, full veraison and post-veraison. Starch levels and amylase activity in leaves, gene expression of sugar transporters in leaves and berries and phloem anatomy were examined at full veraison. Accumulation of glucose and fructose in berries was hastened in ABA-treated plants at the stage of full veraison, which was correlated with enhancement of Vitis vinifera HEXOSE TRANSPORTER 2 (VvHT2) and Vitis vinifera HEXOSE TRANSPORTER 6 (VvHT6) gene expression, increases of phloem area and sucrose content in leaves. On the other hand, GA3 increased the quantity of photoassimilates delivered to the stem thus increasing xylem growth. In conclusion, stimulation of sugar transport by ABA and GA3 to berries and stems, respectively, was due to build-up of non-structural carbohydrates in leaves, modifications in phloem tissue and modulation in gene expression of sugar transporters., (© 2015 Scandinavian Plant Physiology Society.)

Even though vast areas contaminated with arsenic (As) are under soybean (Glycine max) cultivation, little is known about the growth and intrinsic antioxidant metabolism of soybean in response to As exposure. Thus, an evaluation was carried out of plant growth, root anatomy, antioxidant system and photosynthetic pigment content under arsenate (As(V)) and arsenite (As(III)) treatment. Soybean seedling growth was significantly affected at 25 μM or higher concentrations of As(V) or As(III), and the toxic effect on root growth was associated with cell death of root tips. Microscopic analysis of cross-sections of As-treated root showed a reduction in the cortex area, dark deposits in cortex cells and broken cells in the outer layer. Similarly, in the vascular cylinder, dark deposits within xylem vessel elements and phloem cell walls were observed. In all the analyzed parameters, the deleterious effect was more evident under As(III) than As(V) treatment. Arsenic-treated soybean seedlings showed increased activity of antioxidant enzymes [total peroxidases (Px) and superoxide dismutase (SOD)] in root and shoot harvested after 2 and 5 d of treatment. However, a reduction in chlorophyll content and an increase in membrane lipids peroxidation were observed. It is suggested that root structural alterations induced by As, such as the particular pattern of dark depositions in the vascular system, could be associated with an adaptation or detoxification mechanism to prevent As translocation to the aboveground tissues., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Plant growth-promoting rhizobacteria (PGPR) generally exert their effects through enhancement of plant nutrient status and/or phytohormone production. The effects of PGPR on aromatic plant species are poorly known. We measured plant growth parameters, chlorophyll content, trichome density, stomatal density, and levels of secondary metabolites in peppermint (Mentha piperita) seedlings inoculated with PGPR strains Bacillus subtilis GB03, Pseudomonas fluorescens WCS417r, P. putida SJ04, or a combination of WCS417r + SJ04. The treated plants, in comparison with controls, showed increases in shoot biomass, root biomass, leaf area, node number, trichome density, and stomatal density, and marked qualitative and quantitative changes in monoterpene content. Improved knowledge of the factors that control or affect biosynthesis of secondary metabolites and monoterpene accumulation will lead to strategies for improved cultivation and productivity of aromatic plants and other agricultural crops without the use of chemical fertilizers or pesticides.

Phlegmariurus is the only genus of Lycopodiaceae with the species grouped in 22 informal groups. Species level relationships within Phlegmariurus are poorly understood and their circumscriptions require a thorough molecular and morphological review. A detailed study of morphology and anatomy of caulinar axes, lycophylls and sporangia of Phlegmariurus phylicifolius was carried out in order to contribute to the elucidation of species circumscription in the informal group Phlegmariurus phlegmaria. Small pieces of caulinar axes bearing trophophylls, sporophylls and sporangia were fixed, dehydrated, Histowax (paraffin) embedded, sectioned in a rotatory microtome, and stained using the common Safranin O-Fast Green technique; handmade cross sections were also made and stained with the same technique. P. phylicifolius includes slender, pendulous plants up to 40cm long. Shoots heterophyllous, in the basal divisions ca. 10-20(-25) mm in diameter including the trophophylls, then abruptly constricted to (1-) 1.5-2(-2.5) mm in diameter including the imbricate, reduced sporophylls. Trophophylls are borne in alternating whorls of three, or decussate, subdecussate, or alternate, widely spaced in alternate leaved caulinar axes portions, perpendicular to the caulinar axes to falcately ascending, lanceolate to linear-lanceolate, with flat to slightly revolute margins. Each lycophyll is supplied by a single central vascular bundle, connected to a protoxylem pole in the stele. At the site of leaf-trace departure, no leaf (lycophyll) gap is present. Caulinar axes excluding leaves 0.7-1.2 mm thick at the base, upward tapering to ca. 0.5 mm. Caulinar axes present unistratified epidermis and endodermis, the cortex is characterized by the presence of a trabecular structure of lisigenous origin formed in the parenchimatous tissue next to the endodermis. The vascular tissue occupies the central part of the caulinar axes, forming a plectostele ofsubradiate organization, with five poles ofprotoxylem. The epidermal cells present sinuous anticlinal walls; invaginations in the inner side of external periclinal wall of the epidermal cells could be probably adaptive morphological feature of a water deficient environment. Leaves of constricted terminal divi- sions are decussate, or subdecussate, continuously or discontinuously sporangiate, appressed, abaxially rounded to carinate, widely lanceolate to widely ovate or subcordate, acute to mucronate or cuspidate, shorter than the sporangia. Each sporangium originates from a group of epidermal cells, axilar to the sporophylls. The cell walls of epidermal cell of the sporangia are Huperzioideae type. The morphological studies of trophophylls contribute to confirm the differences between P. phylicifolius and P. subulatus.

Halophytes are potential gene sources for genetic manipulation of economically important crop species. This study addresses the physiological responses of a widespread halophyte, Prosopis strombulifera (Lam.) Benth to salinity. We hypothesised that increasing concentrations of the two major salts present in soils of central Argentina (Na2SO4, NaCl, or their iso-osmotic mixture) would produce distinct physiological responses. We used hydroponically grown P. strombulifera to test this hypothesis, analysing growth parameters, water relations, photosynthetic pigments, cations and anions. These plants showed a halophytic response to NaCl, but strong general inhibition of growth in response to iso-osmotic solutions containing Na2SO4. The explanation for the adaptive success of P. strombulifera in high NaCl conditions seems to be related to a delicate balance between Na(+) accumulation (and its use for osmotic adjustment) and efficient compartmentalisation in vacuoles, the ability of the whole plant to ensure sufficient K(+) supply by maintaining high K(+)/Na(+) discrimination, and maintenance of normal Ca(2+) levels in leaves. The three salt treatments had different effects on the accumulation of ions. Findings in bi-saline-treated plants were of particular interest, where most of the physiological parameters studied showed partial alleviation of SO4(2-)-induced toxicity by Cl(-). Thus, discussions on physiological responses to salinity could be further expanded in a way that more closely mimics natural salt environments., (© 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.)

We evaluated the production of indole-3-acetic acid (IAA) by Azospirillum brasilense strains in vitro (cell culture supernatants) and in vivo (stems and roots of maize seedlings) to clarify the role of this phytohormone as a signaling and effector molecule in the symbiotic interaction between maize and A. brasilense. The three strains all showed IAA production when cultured in NFb medium supplemented with 100 μg/ml L-tryptophan. The level of IAA production was 41.5 μg/ml for Yu62, 12.9 μg/ml for Az39, and 0.15 μg/ml for ipdC-. The release of IAA into culture medium by the bacteria appeared to be the main activator of the early growth promotion observed in the inoculated maize seedlings. The application of supernatants with different IAA contents caused significant differences in the seedling growth. This observation provides the basis for novel technological tools for effective quality control procedures on inoculants. The approach described can be incorporated into different inoculation methods, including line sowing, downspout, and foliar techniques, and increase the sustainability of symbiotic plant-bacteria systems.

Introduction: The purpose of this study is to measure the impact of a psychoeducational group intervention in diabetes using glycosylated haemoglobin (HbA1c), the body mass index (BMI) and cardiovascular risk factors (CVRF) compared with conventional educational measures provided individually., Methods: A quasi-experimental study (pre/post-intervention) with a non-equivalent control group was conducted, including 72 type 2 individuals with diabetes (mean data: age 63.08 years, HbA1C 6.98%, BMI 30.48 kg/m2).The beneficial effect of psychoeducational group therapy in the study group (PGT) was compared with conventional diabetes education in the control group (CG)., Results: The PGT had a higher mean HbA1c reduction (-0.51 ± 1.7 vs. -0.06 ± 0.53%, p 0.003), met the objectives of optimal control of HbA1c to a higher degree (80% vs. 48%, p 0.005) and greater mean weight reduction (-1.93 ± 3.57 vs. 0.52 ± 1.73 kg, p 0002) than the CG.A significant improvement in total cholesterol, LDL cholesterol, triglycerides, systolic and diastolic blood pressure was achieved in PGT (all p < 0.05)., Conclusions: PGT patients achieved a significant improvement in HbA1C, BMI and CVRF, and outperformed the conventional diabetes education group in achieving the optimal diabetes control objectives. Structural changes in the assistance programs should be considered to introduce these more efficient therapies for diabetes education in primary care., (Copyright © AULA MEDICA EDICIONES 2013. Published by AULA MEDICA. All rights reserved.)

Nowadays, soil salinity is the most unfavourable abiotic factors for plant growth, causing important yield loss of many crops. A partial solution to this situation is to establish crop varieties in these areas affected which are tolerant to stress. The aim of this study was to evaluate in a wheat variety, the morphophysiological plasticity to sodium chloride (NaCl) stress and the effect of exogenous Abscisic Acid (ABA) on physiological variables. This was carried out by using the BI3000 wheat variety, for regional adaptability experiments. The germination percentage, coleoptile and radicle growth and root anatomic were evaluated, both seedling irrigated with water or saline solution. On the other hand, ABA sprays were applied to wheat plants and their biomass, pigment, stomatal behaviour and cellular membrane injuries were determined after salt treatments. In this study, it was possible to determine that the BI3000 wheat variety can grow in high electrical conductivity, with good germination and seedling growth. This variety showed less radical anatomic variations under salinity, what allows a faster plasticity to adapt. ABA applications suggest a protective role in plants under salinity, due to an increase in chlorophyll and carotene content, stability of cell membranes and stomatal behavior. This study is a contribution to a better understanding of the morphophysiological responses of glycophytic plants to salt stress. This have been pointed out as a useful approach to show more tolerance to salt stress crops in the future and it suggests that ABA could help improve agriculture production in areas affected by this stress.

In previous works we have characterized the native bacterial diversity associated with root nodules of peanut grown in Córdoba province, Argentina. Studies performed in the isolate Rhizobium sp. NET30 revealed a phylogenetic incongruence between housekeeping and nodulation genes. This discrepancy could be explained by the horizontal transfer of nodulation genes from the native peanut isolate Rhizobium sp. NCHA22, a bacterium that showed high identity percentages with Rhizobium tropici IIB strains in the basic and symbiotic genes analyzed. In this work, we demonstrate that, in R. sp. NCHA22, genes required for nodule formation in common bean (Phaseolus vulgaris L.) are plasmid-borne. A symbiotic plasmid capable of conjugal transfer to different genetic backgrounds was identified in this isolate. The mechanism involved in the plasmidic transfer differs from that described for R. tropici CIAT899 (R. tropici IIB type strain). The transfer of a symbiotic plasmid, and the subsequent homologous recombination of nodulation genes in R. sp. NET30 genetic background could account for the phylogenetic incongruence determined in this isolate. Results are also indicating that the transfer of the R. tropici NCHA22 pSym may be a frequent event in native conditions., (Copyright 2009 Elsevier GmbH. All rights reserved.)

A highly basic peroxidase isoenzyme was shown to be released to the culture medium of tomato (Lycopersicon esculentum) hairy roots grown in Murashige-Skoog (MS) liquid medium when it was supplemented with 100 mM NaCl. In this paper we demonstrate that this enzyme is ionically bound to cell walls and that the release was a consequence of the continuous agitation of the tissue in a high ionic strength medium with salt addition. In order to establish the physiological role of this isoenzyme we partially purified it, and we analysed its kinetic properties as coniferyl alcohol peroxidase. The peroxidase isoenzyme showed a high catalytic efficiency for this substrate, which suggests that it would be associated with the ligno-suberization process. To confirm the involvement of this isoenzyme in that process, we studied the pattern of ligno-suberization of the tissue under different conditions of growth. Our results suggest that this basic peroxidase would be indeed involved in ligno-suberization since its leakage from cell walls, induced by 100 mM NaCl in liquid MS, caused less ligno-suberization of exo and endodermis. On the contrary, more ligno-suberization was seen in cell walls when the hairy roots were grown in a salt-supplemented MS solid medium without contact with it, a condition in which the release of the isoenzyme would be avoided. Thus, through the changes produced by the release of the enzyme from its site of action, we could demonstrate the physiological role of this peroxidase in the processing of root cell walls, being part of control mechanisms of ion and water fluxes through the root.

Background and Aims: Salinity can affect germination of seeds either by creating osmotic potentials that prevent water uptake or by toxic effects of specific ions. Most studies have only used monosaline solutions, although these limit the extent to which one can interpret the results or relate them to field conditions. The aim of this work was to evaluate the germination of Prosopis strombulifera seeds under increasing salinity by using the most abundant salts in central Argentina in monosaline or bisaline iso-osmotic solutions, or in solutions of mannitol and polyethylene glycol., Methods: Seeds were allowed to germinate under controlled conditions in a germination chamber at 30 +/- 1 degrees C and at 80 % r.h. Salinizing agents were KCl, NaCl, Na(2)SO(4), K(2)SO(4), NaCl + Na(2)SO(4) and KCl + K(2)SO(4) and osmotic agents were polyethylene glycol 6000 and mannitol. Treatments for all osmotica consisted of 0.0, -0.4, -0.8, -1.2, -1.5, -1.9 and -2.2 MPa solutions., Key Results: The percentage of germination decreased as salinity increased. SO(4)(2-) in monosaline solutions, with osmotic potentials -1.2 MPa and lower, was more inhibitory than Cl(-) at iso-osmotic concentrations. This SO(4)(2-) toxicity was alleviated in salt mixtures and was more noticeable in higher concentrations. K(+) was more inhibitory than Na(+) independently of the accompanying anion., Conclusions: Different responses to different compositions of iso-osmotic salt solutions and to both osmotic agents indicate specific ionic effects. This study demonstrates that the germination of P. strombulifera is strongly influenced by the nature of the ions in the salt solutions and their interactions. Comparative studies of Cl(-) and SO(4)(2-) effects and the interaction between SO(4)(2-) and Cl(-) in salt mixtures indicate that extrapolation of results obtained with monosaline solutions in the laboratory to field conditions can be speculative.

Flower buds of peach (Prunus persica L.) trees, cv Novedad de Cordoba (Argentina), were collected near the end of the dormant period and immediately before anthesis. After removal of scale leaves, morphological observations of representative buds, made on transverse and longitudinal microtome sections, showed that all verticils making up the flower are present in an undifferentiated form during the dormant period (June). Flower buds collected at the end of dormant period (August) showed additional growth and differentiation, at which time formation of two ovules was beginning in the unicarpelar gynoecium. Dehiscence of anthers had not yet occurred 10 days before full bloom, and the ovules were still developing. Free endogenous gibberellin (GA)-like substances were quantified by bioassay (Tan-ginbozu dwarf rice microdrop) after SiO(2) partition column chromatography, reversed phase C18-high performance liquid chromatography, and finally Nucleosil [N(CH(3))(2)]high performance liquid chromatography. Bioactive fractions were then subjected to capillary gas chromatography-mass spectrometry-selected ion monitoring (GC-MS-SIM). Gibberellins A(1), A(3), and A(8) were tentatively identified in peach flower buds using GC-SIM and Kovat's retention indices, and relative amounts approximated by GC-SIM (2:8:6 for GA(1), GA(3), and GA(8), respectively). The highest concentration (330 nanograms per gram dry weight) of free GA(1)/GA(3) was found in dormant buds (June) and diminished thereafter. The concentration free of GA(1)/GA(3) did not increase immediately prior to bud break. However, high GA(1)/GA(3) concentrations occurred during stages where rate of growth and cellular differentiation of (mainly fertile) verticils can be influenced.