Intercellular pectic protuberances in leaves of some Xyris species (Xyridaceae)

Mature leaves of eight species of Xyris were prepared by standard methods for electron transmission microscopy. Wartlike intercellular pectic protuberances were observed on the surface of inner periclinal walls of epidermal cells in Xyris obcordata, Xyris hymenachne, and Xyris pterygoblephara. In the latter, the protuberances also occur on the surface of parenchymatic mesophyll cells; they frequently project into intercellular spaces and may connect opposing cells. For the genus Xyris, the intercellular pectic protuberances may be considered taxonomically significant at the species level.

Stress-induced subsensitivity to catecholamines depends on the estrous cycle

In this article we compare how sensitivity to the chronotropic effect of noradrenaline and adrenaline of right atria isolated from female rats is modified after repeated swimming or foot-shock stress, under the influence of the estrous cycle. Right atria from stressed female rats sacrificed at diestrus were subsensitive to both catecholamines, irrespective of the stressor agent. However, although subsensitivity to noradrenaline was of similar intensity, subsensitivity to adrenaline was more pronounced in right atria from foot shock stressed rats as opposed to swimming-stressed rats. Identical stress protocols did not induce any alteration in atrial sensitivity to catecholamines when the stressed female rats were sacrificed at estrus. We conclude that the stress reaction concerning the mediation of cardiac chronotropism by catecholamines is related to the severity of the stressor agent and is strongly influenced by the estrous cycle.

Genetic recombinants in Trichoderma pseudokoningii (Rifai) without typical parasexuality

Heterokaryons were obtained by hyphal anastomosis in Trichoderma pseudokoningii using strains with morphologic and double auxotrophic genetic markers. Stable haploid and unstable hyperhaploid recombinants were detected in monosporic colonies derived from heterokaryons and selected in appropriate media or by an enrichment filtration technique. Diploids were not observed and the recombinant frequencies were higher than those found in fungi with a typical parasexual cycle. The mechanism of recombinant emergence may involve a transient diploid formation followed by chromosomal losses at the hyphal stages, resulting in haploid and hyperhaploid recombinants. The possibility of intrachromosomal rearrangement with the involvement of cytoplasmatic DNA as a heterokaryotic transformation system cannot be excluded.

REACTIVE OXYGEN GENERATION BY AZOMETHINE-H - A NEW ANTIMALARIAL DRUG

Superoxide radical (O-2(-)) is a free radical that may be involved in various toxic processes. Cu-Zn superoxide dismutase catalyzes the dismutation of the superoxide free radical and protects cells from oxidative damage. A rat bioassay validated for the identification of the toxic effects of azomethine H revealed increased serum activities of amylase, alanine transaminase, and alkaline phosphatase. The lipoperoxide and bilirubin concentrations were also increased in animals that received azomethine H (1 g/kg) from ascorbic or hydrochloric acid solutions. Azomethine H increased Cu-Zn superoxide dismutase activity. This elevation of Cu-Zn superoxide dismutase activity was highest on the 7th day and was at levels comparable with those of control rats from day 60 onwards. Superoxide is an important intermediate in the action and toxicity of azomethine H.

EXTRAFLORAL NECTARIES IN THE TROPICAL TREE GUAREA-MACROPHYLLA (MELIACEAE)

This paper describes the anatomy and morphology of the complex nectary systems of the tropical tree Guarea macrophylla Vahl (Meliaceae) and presents the first record of extrafloral nectaries occurring on reproductive organs (fruits) of a member of the order Sapindales. The extrafloral nectaries of G. macrophylla occur on petioles, petiolules, the abaxial surface of all leaflets, leaf buds, and over the surface of fruits. All extrafloral nectaries are distinctly raised above the surface. Foraging ants collect extrafloral nectar on Guarea trees both day and night. We suggest that the presence of extrafloral nectaries might be a useful taxonomic character for the identification of Guarea species.

The bizarre male of Spalangia dozieri (Hymenoptera: Pteromalidae): adaptations for male phoresy or the result of sexual selection?

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Revisiting privatization, foreign investment, international arbitration, and water

Includes bibliography

EC32-713 The Trench Silo in Nebraska

The original idea of using a trench for the storing of ensilage seems to have been the outgrowth of the practice long used in several European countries of storing clover and beet tops in pits. Shortly after the World War, western Canada followed by Montana and North Dakota began to use the trench silo. In Nebraska the true trench silo made its appearance about 1925 or 1926. The trench silo as described in this circular, unless lined with some permanent material such as brick, concrete or stone, must be considered a temporary structure which will serve for a few years only and then must be discarded or rebuilt. In an emergency it will save a crop even though the farmer has little capital to expend other than his own labor.

Rural Nebraska: Looking Back at a Decade of Change and Progress: 2005 Nebraska Rural Poll Results

To commemorate the 10th anniversary of the Nebraska Rural Poll, rural Nebraskans were asked about changes they may have experienced during the past ten years. Where have they lived during the past decade? In what types of business activities have they been involved? Have they received any education or training during that time period? What has been their experience with the Internet? This report details 2,851 responses to the 2005 Nebraska Rural Poll, the tenth annual effort to understand rural Nebraskans’ perceptions. Respondents were asked a series of questions about changes they have experienced during the past ten years. For all questions, comparisons are made among different respondent subgroups, that is, comparisons by age, occupation, region, etc. Based on these analyses, some key findings emerged: One quarter of rural Nebraskans have lived somewhere other than their current community during the past ten years. Of those who have lived elsewhere, they have moved their primary residence an average of 2.2 times. Younger rural Nebraskans are more likely than older residents to have lived elsewhere during the past decade. Sixty-six percent of persons between the ages of 19 and 29 have lived in a different location, compared to only 12 percent of persons age 65 and older. Many rural Nebraskans who have lived in a different community during the past ten years have lived in another state. Forty-one percent of persons who have lived elsewhere during the past decade have lived in a different state. Forty-five percent have lived in a larger community (18% have lived in either Omaha or Lincoln and 27% have lived in or near a Nebraska community larger than their current one - other than Lincoln or Omaha). Thirty-six percent have lived in or near a Nebraska community smaller than their current one. Twenty percent of rural Nebraskans currently own a business. Thirteen percent started operating a business during the past ten years, 10 percent closed or stopped operating a business during this time period and four percent tried unsuccessfully to start a business. Persons living in or near the smallest communities are more likely than persons living in or near larger communities to currently own a business. Twenty-nine percent of persons living in or near communities with less than 500 people currently own a business, compared to 15 percent of persons living in or near communities with at least 10,000 persons. In general, rural Nebraskans have favorable opinions about self-employment but they also recognize the hardships and risks involved with this type of employment. Sixtyone percent agree that self-employment is desirable because they can be their own boss. Forty-four percent agree that self-employment provides a better quality of life than being an employee. However, 74 percent agree that self-employed individuals work longer hours than traditional employees and 70 percent agree that the cost of health insurance makes self-employment unappealing. Younger persons are more likely than older persons to agree that the cost of health insurance makes self-employment unappealing. Eighty percent of persons age 19 to 29 agree with that statement, compared to 55 percent of persons age 65 and older. One-half of rural Nebraskans have participated in formal education courses, workshops or other training activities during the past ten years. Sixty-nine percent of rural Nebraskans have Internet access either at home or at work. Sixty-six percent have acquired Internet access either at home or at work during the past ten years. An additional three percent had acquired access more than ten years ago. Persons with higher levels of income are more likely than persons with lower incomes to have acquired Internet access. Sixty-six percent of persons with household incomes of $60,000 or more have acquired Internet access at both home and work during the past ten years, compared to only 11 percent of persons with household incomes less than $20,000. Information searches and email are the most important reasons for having an Internet connection. Eighty-nine percent of rural Nebraskans with access to the Internet at either home or work say that information searches are an important or very important reason for having an Internet connection. Eighty-three percent say email is an important reason. In general, rural Nebraskans say their satisfaction with various features of their Internet connection has increased during the past ten years. Fifty-five percent of rural Nebraskans with an Internet connection at home say their satisfaction with the availability of service has increased during the past ten years and 50 percent report an increase in their satisfaction with the speed of their connection. Persons living in or near the larger communities are more likely than persons living in or near the smaller communities to say their satisfaction with the speed of their Internet connection has increased during the past ten years. Fifty-four percent of persons living in or near communities with populations of 5,000 or more say their satisfaction with the speed of their connection has increased over the past decade, compared to 43 percent of persons living in or near communities with less than 1,000 people.

Consumer attitudes, knowledge, and behavior related to salt consumption in sentinel countries of the Americas

Objective. To describe individual attitudes, knowledge, and behavior regarding salt intake, its dietary sources, and current food-labeling practices related to salt and sodium in five sentinel countries of the Americas. Methods. A convenience sample of 1 992 adults (>= 18 years old) from Argentina, Canada, Chile, Costa Rica, and Ecuador (approximately 400 from each country) was obtained between September 2010 and February 2011. Data collection was conducted in shopping malls or major commercial areas using a questionnaire containing 33 questions. Descriptive estimates are presented for the total sample and stratified by country and sociodemographic characteristics of the studied population. Results. Almost 90% of participants associated excess intake of salt with the occurrence of adverse health conditions, more than 60% indicated they were trying to reduce their current intake of salt, and more than 30% believed reducing dietary salt to be of high importance. Only 26% of participants claimed to know the existence of a recommended maximum value of salt or sodium intake and 47% of them stated they knew the content of salt in food items. More than 80% of participants said that they would like food labeling to indicate high, medium, and low levels of salt or sodium and would like to see a clear warning label on packages of foods high in salt. Conclusions. Additional effort is required to increase consumers' knowledge about the existence of a maximum limit for intake and to improve their capacity to accurately monitor and reduce their personal salt consumption.

Mutations in SRCAP, Encoding SNF2-Related CREBBP Activator Protein, Cause Floating-Harbor Syndrome

Floating-Harbor syndrome (FHS) is a rare condition characterized by short stature, delayed osseous maturation, expressive-language deficits, and a distinctive facial appearance. Occurrence is generally sporadic, although parent-to-child transmission has been reported on occasion. Employing whole-exome sequencing, we identified heterozygous truncating mutations in SRCAP in five unrelated individuals with sporadic MS. Sanger sequencing identified mutations in SRCAP in eight more affected persons. Mutations were de novo in all six instances in which parental DNA was available. SRCAP is an SNF2-related chromatin-remodeling factor that serves as a coactivator for CREB-binding protein (CREBBP, better known as CBP, the major cause of Rubinstein-Taybi syndrome [RTS]). Five SRCAP mutations, two of which are recurrent, were identified; all are tightly clustered within a small (111 codon) region of the final exon. These mutations are predicted to abolish three C-terminal AT-hook DNA-binding motifs while leaving the CBP-binding and ATPase domains intact. Our findings show that SRCAP mutations are the major cause of FHS and offer an explanation for the clinical overlap between FHS and RTS.

Haploinsufficiency of a Spliceosomal GTPase Encoded by EFTUD2 Causes Mandibulofacial Dysostosis with Microcephaly

Mandibulofacial dysostosis with microcephaly (MFDM) is a rare sporadic syndrome comprising craniofacial malformations, microcephaly, developmental delay, and a recognizable dysmorphic appearance. Major sequelae, including choanal atresia, sensorineural hearing loss, and cleft palate, each occur in a significant proportion of affected individuals. We present detailed clinical findings in 12 unrelated individuals with MFDM; these 12 individuals compose the largest reported cohort to date. To define the etiology of MFDM, we employed whole-exome sequencing of four unrelated affected individuals and identified heterozygous mutations or deletions of EFTUD2 in all four. Validation studies of eight additional individuals with MFDM demonstrated causative EFTUD2 mutations in all affected individuals tested. A range of EPTUD2-mutation types, including null alleles and frameshifts, is seen in MFDM, consistent with haploinsufficiency; segregation is de novo in all cases assessed to date. U5-116kD, the protein encoded by EFTUD2, is a highly conserved spliceosomal GTPase with a central regulatory role in catalytic splicing and post-splicing-complex disassembly. MFDM is the fast multiple-malformation syndrome attributed to a defect of the major spliceosome. Our findings significantly extend the range of reported spliceosomal phenotypes in humans and pave the way for further investigation in related conditions such as Treacher Collins syndrome.

Developmental and Epigenetic Anomalies in Cloned Cattle

Many of the developmental anomalies observed in cloned animals are related to foetal and placental overgrowth, a phenomenon known as the 'large offspring syndrome' (LOS) in ruminants. It has been hypothesized that the epigenetic control of imprinted genes, that is, genes that are expressed in a parental-specific manner, is at the root of LOS. Our recent research has focused on understanding epigenetic alterations to imprinted genes that are associated with assisted reproductive technologies (ART), such as early embryo in vitro culture (IVC) and somatic cell nuclear transfer (SCNT) in cattle. We have sought and identified single nucleotide polymorphisms in Bos indicus DNA useful for the analysis of parental-specific alleles and their respective transcripts in tissues from hybrid embryos derived by crossing Bos indicus and Bos taurus cattle. By analysing differentially methylated regions (DMRs) of imprinted genes SNRPN, H19 and the IGF2R in cattle, we demonstrated that there is a generalized hypomethylation of the imprinted allele and the biallelic expression of embryos produced by SCNT when compared to the methylation patterns observed in vivo (artificially inseminated). Together, these results indicate that imprinting marks are erased during the reprogramming of the somatic cell nucleus during early development, indicating that such epigenetic anomalies may play a key role in mortality and morbidity of cloned animals.

The unconventional secretion of stress-inducible protein 1 by a heterogeneous population of extracellular vesicles

The co-chaperone stress-inducible protein 1 (STI1) is released by astrocytes, and has important neurotrophic properties upon binding to prion protein (PrPC). However, STI1 lacks a signal peptide and pharmacological approaches pointed that it does not follow a classical secretion mechanism. Ultracentrifugation, size exclusion chromatography, electron microscopy, vesicle labeling, and particle tracking analysis were used to identify three major types of extracellular vesicles (EVs) released from astrocytes with sizes ranging from 20–50, 100–200, and 300–400 nm. These EVs carry STI1 and present many exosomal markers, even though only a subpopulation had the typical exosomal morphology. The only protein, from those evaluated here, present exclusively in vesicles that have exosomal morphology was PrPC. STI1 partially co-localized with Rab5 and Rab7 in endosomal compartments, and a dominant-negative for vacuolar protein sorting 4A (VPS4A), required for formation of multivesicular bodies (MVBs), impaired EV and STI1 release. Flow cytometry and PK digestion demonstrated that STI1 localized to the outer leaflet of EVs, and its association with EVs greatly increased STI1 activity upon PrPC-dependent neuronal signaling. These results indicate that astrocytes secrete a diverse population of EVs derived from MVBs that contain STI1 and suggest that the interaction between EVs and neuronal surface components enhances STI1–PrPC signaling