Nuclear and Organelle DNA Replication during Spore Germination in Bryophytes and Equisetum

In contrast to ferns, the spore nuclei of the moss, Funaria hygrometrica, are in the G₂ phase. They do not incorporate the thymidine analogue BUdr before the first mitosis. When spores germinate in the presence of aphidicolin, an inhibitor of the (nuclear) DNA polymerase alpha, they give rise to two-celled, negatively phototropic protonemata, consisting of relatively long and thin cells. Determinations of nuclear DNA content further confirm the presence of G₂-nuclei in Funaria spores. Spores of Pogonatum urnigerum and of Equisetum hyemale likewise contain G₂-nuclei, as shown by BUdr incorporation or experiments with aphidicolin, respectively. In germinating Funaria spores, the organelle DNA is synthesized very early and independent of nuclear DNA. A gradient in replication of organelle DNA is found only in the long tip cells which are formed in the presence of aphidicolin.     

Treatment with pronase uncouples water and sugar reception in the lahellar water receptor of the blowfly

Summary Standard spider frames were continuously rotated in a vertical klinostat at different speeds, changed each day, in a rising sequence through 0.3, 0.7, 2.3, 4.9, 10, 20, 30, and 60 rpm. They were also rotated at various speeds between 100 and 150 rpm. Speed of rotation did have a marked effect on a number of web parameters. It is concluded that gravity is an important compass reference for orientation during web construction. The effect was greatest at medium speeds, and less pronounced not only at slower but also at higher speeds. The most striking effect was the complete disorientation of the spider during construction of the capture spiral at 5 and 10 rpm. Surprisingly no comparable disorientation was found in the auxiliary spiral. This suggests different orientation mechanisms for the two spirals. The ability to orient the capture spiral at high speeds may be due to the effect of centripetal forces, but it may also be attributed to an evolutionary adaptation to building in windy environments where the spider might experience linear accelerations of severalg.Abbreviation rpm rotations per minute     

Androgen Treatment of Abdominally Obese Men

Middle-aged men with abdominal obesity were treated in a double-blind study with moderate doses of transdermal preparations of testosterone (T), dihydrotestosterone (DHT), or placebo. This resulted in moderately elevated T concentrations and marked decreases in follicle stimulating and luteinizing hormones in the group treated with T, while the DHT group showed elevated DHT, markedly lower T values, and less diminution of gonadotropin concentrations. In the group treated with T visceral fat mass decreased (measured by computerized tomography) without significant changes in other depot fat regions. Lean body mass did not change. In the group treated with T, glucose disposal rate, measured with the euglycemic hyperinsulinemic clamp method, was markedly augmented. Plasma triglycerides, cholesterol, and fasting blood glucose concentrations as well as diastolic blood pressure decreased. There were no such changes in the DHT or placebo treatment groups. The men treated with T reported increased well-being and energy. In none of the groups did prostate volume, specific prostate antigen concentration, genitourinary history, or urinary flow measurement change. It is suggested that supplementation of abdominal obese men with moderate doses of T might have several beneficial effects. (OBESITY RESEARCH 1993;1:245–251)     

Head-neck domain of <Emphasis Type="Italic">Arabidopsis</Emphasis> myosin XI,MYA2, fused with GFP produces F-actin patterns that coincide with fast organelle streaming in different plant cells

Background  

The cytoskeletal mechanisms that underlie organelle transport in plants are intimately linked to acto-myosin function. This function is mediated by the attachment of myosin heads to F-actin and the binding of cargo to the tails. Acto-myosin also powers vigorous cytoplasmic streaming in plant cells. Class XI myosins exhibit strikingly fast velocities and may have extraordinary roles in cellular motility. Studies of the structural basis of organelle transport have focused on the cargo-binding tails of myosin XI, revealing a close relationship with the transport of peroxisomes, mitochondria, and Golgi-vesicles. Links between myosin heads and F-actin-based motility have been less investigated. To address this function, we performed localization studies using the head-neck domain of AtMYA2, a myosin XI from Arabidopsis.     

The morphology of the reproductive system in the crab Percnon gibbesi (Decapoda: Brachyura: Grapsoidea) reveals a new combination of characters in Thoracotremata

Recent studies revealed a high diversity of reproductive structures in heterotreme brachyurans, while those of Thoracotremata seem rather uniform. Yet, there still is a huge lack of data in this group as only few species have been studied with respect to their reproductive system. The phylogenetic position of Percnidae is ambiguous. Recent molecular studies place it within polyphyletic grapsoids. We herein study the reproductive morphology of Percnon gibbesi using histology, scanning electron microscopy, micro‐computed tomography and 3D‐reconstructions to test whether this species shows the characteristic thoracotreme pattern. Our results reveal that the male copulatory system conforms to other thoracotremes. It is composed of two pairs of pleopods (gonopods) and likewise paired penes. The first gonopod is relatively long. It possesses a bent terminal process with a distal opening of the ejaculatory canal, a character also present in other grapsoids. The second gonopod is short and terminates in an apical girdle. The female reproductive system reveals a combination of characters, so far unknown for thoracotremes. The paired oviducts do not lead into the seminal receptacles, but run into separate cuticular ducts joined with the vaginae. Accessory sperm storage organs, the bursae, are also connected to the vaginae. Bursae have previously only been described in heterotreme crabs. The data presented in this study reveals a higher diversity of thoracotreme reproductive systems than anticipated.     

Ingestion of colostrum from specific cows induces Bovine Neonatal Pancytopenia (BNP) in some calves

Background  

Since 2006, cases of haemorrhagic diathesis in young calves have been observed with a much higher incidence than previously known. The syndrome, now uniformly called Bovine Neonatal Pancytopenia (BNP), is characterized by multiple (external and internal) haemorrhages, thrombocytopenia, leukocytopenia, and bone marrow depletion. Although various infectious and toxicological causes of bleeding disorders in calves have been ruled out, the aetiology of BNP remains unknown. However, field observations have led to the hypothesis that the aetiological principle may be transmitted to calves via colostrum.     

Cypriniform fish in running waters reduce hyporheic oxygen depletion in a eutrophic river

1. The hyporheic zone is an important habitat for benthic invertebrates and early-developmental stages of gravel spawning fish. However, the eutrophication of running waters and, in turn, the excessive periphyton biomass leads to its biological clogging. The result of these processes is oxygen depletion and a reduction in the habitat quality of the hyporheic zone.
2. This study assessed whether top-down effects of two important European river fish species, the large herbivorous cypriniform common nase (Chondrostoma nasus, L.) and the large omnivorous cypriniform European chub (Squalius cephalus, L.), can reduce eutrophication effects in the hyporheic zone. A 4-week mesocosm-based field experiment in a eutrophic river was conducted using cage enclosures stocked or not with either nase or chub.
3. The top-down control of periphyton was expected to reduce biological clogging and thereby increase oxygen availability in the hyporheic zone. Accordingly, we hypothesised that in enclosures stocked with either fish the concentrations of dissolved oxygen in the hyporheic zone would be higher and the periphyton biomass would be lower than in enclosures without fish stocking.
4. Hyporheic oxygen concentrations were significantly higher in enclosures stocked with either nase or chub than in enclosures without fish stocking. However, periphyton ash-free dry mass was significantly reduced only in enclosures stocked with nase, not in those stocked with chub. Thus, the positive effects of nase and chub on hyporheic oxygen availability were caused by different mechanisms.
5. Our results demonstrate that nase and chub can reduce eutrophication effects in the hyporheic zone of running waters. Hence, protecting and enhancing stocks of herbivorous and omnivorous fish will contribute to restoring the hyporheic zone in efforts to preserve biodiversity in eutrophic rivers.

     

Motivation Matters: Lessons for REDD+ Participatory Measurement,Reporting and Verification from Three Decades of Child Health Participatory Monitoring in Indonesia

Participatory Measurement, Reporting and Verification (PMRV), in the context of reducing emissions from deforestation and forest degradation with its co-benefits (REDD+) requires sustained monitoring and reporting by community members. This requirement appears challenging and has yet to be achieved. Other successful, long established, community self-monitoring and reporting systems may provide valuable lessons. The Indonesian integrated village healthcare program (Posyandu) was initiated in the 1980s and still provides effective and successful participatory measurement and reporting of child health status across the diverse, and often remote, communities of Indonesia. Posyandu activities focus on the growth and development of children under the age of five by recording their height and weight and reporting these monthly to the Ministry of Health. Here we focus on the local Posyandu personnel (kaders) and their motivations and incentives for contributing. While Posyandu and REDD+ measurement and reporting activities differ, there are sufficient commonalities to draw useful lessons. We find that the Posyandu kaders are motivated by their interests in health care, by their belief that it benefits the community, and by encouragement by local leaders. Recognition from the community, status within the system, training opportunities, competition among communities, and small payments provide incentives to sustain participation. We examine these lessons in the context of REDD+.     

Phylogenetic analysis ofEremosyne pectinata (Saxifragaceae s. l.) based onrbcL sequence data

Earlier analyses ofrbcL sequences clarified phylogenetic relationships of 16 of 17 subfamilies ofSaxifragaceae s. l. This study investigates the affinities of the monotypicEremosynoideae, the only subfamily ofSaxifragaceae s. l. not examined previously forrbcL sequence variation. Our analyses suggest thatEremosyne is only distantly related to core members ofSaxifragaceae s. l. (i.e.Saxifragoideae = Saxifragaceae s. str.); it is allied instead with members ofAsteridae. A particularly close relationship is indicated betweenEremosyne andEscallonia, another traditional member ofSaxifragaceae s. l. that also appears as part ofAsteridae. Inclusion ofEremosyne withinAsteridae is in agreement with embryology, as well as with 18S rDNA sequence data.