bluuebunny/crossref_metadata_2025 huggingface dataset:
Circulating microRNAs in exosomes indicate hepatocyte injury and inflammation in alcoholic, drug-induced, and inflammatory liver diseases
Authors: Bala Shashi , Petrasek Jan , Mundkur Shiv , Catalano Donna , Levin Ivan , Ward Jeanine , Alao Hawau , Kodys Karen , Szabo Gyongyi
Published: June 2012

MicroRNAs are fine tuners of diverse biological responses and are expressed in various cell types of the liver. Here we hypothesized that circulating microRNAs (miRNAs) may serve as biomarkers of liver damage and inflammation. We studied miRNA-122, which is abundant in hepatocytes, and miR-155, -146a, and -125b, which regulate inflammation in immune cells in mouse models of alcoholic liver disease (ALD), drug (acetaminophen, APAP)-induced liver injury (DILI), and Toll-like receptor (TLR) 9+4 ligand-induced inflammatory cell-mediated liver damage. We found that serum/plasma miR-122 correlated with alanine aminotransferase (ALT) increases in the liver damage caused by alcohol, APAP, and TLR9 (CpG)+4 (LPS) ligands. MiR-155, a regulator of inflammation, was increased in serum/plasma in alcoholic and inflammatory liver injury. Alcohol failed to increase serum miR-122 in TLR4-deficient and p47phox-deficient mice that were protected from ALD. We found the most robust increase in plasma miR-122 in DILI and it correlated with the highest ALT levels. Consistent with the massive inflammatory cell infiltration in the liver, plasma miR-155 and miR-146a were significantly elevated after CpG+LPS administration. We show for the first time that, depending on the type of liver injury, circulating miRNAs are associated either with the exosome-rich or protein-rich compartments. In ALD and in inflammatory liver injury, serum/plasma miR-122 and miR-155 were predominantly associated with the exosome-rich fraction, whereas in DILI/APAP injury these miRNAs were present in the protein-rich fraction.

Conclusion:

Our results suggest that circulating miRNAs may serve as biomarkers to differentiate between hepatocyte injury and inflammation and the exosome versus protein association of miRNAs may provide further specificity to mechanisms of liver pathology.
Regulation of archicortical arealization by the transcription factor Zbtb20
Authors: Rosenthal Eva H. , Tonchev Anton B. , Stoykova Anastassia , Chowdhury Kamal
Published: June 2012

The molecular mechanisms of regionalization of the medial pallium (MP), the anlage of the hippocampus, and transitional (cingulate and retrosplenial) cortices are largely unknown. Previous analyses have outlined an important role of the transcription factor (TF) Zbtb20 for hippocampal CA1 field specification (Nielsen et al. (2007) Development 134:1133‐1140; Nielsen et al. (2010) Cereb Cortex 20:1904‐1914; Xie et al. (2010) Proc Natl Acad Sci USA 107:6510‐6515). Here, we present novel data showing that Zbtb20 exhibits a ventralhigh‐to‐dorsallow gradient of expression in MP progenitors as well as an expression in postmitotic cells at the transitional cortex/neocortex border. Our detailed pattern analysis revealed that in Zbtb20 loss‐of‐function the molecular borders between neocortical, transitional, and hippocampal fields are progressively shifted ventrally, leading to an ectopic positioning of all dorsal fields into the neighboring ventrally located areas. Thus, in addition to its known importance for the specification of the hippocampal CA1 sector, the graded expression of TF Zbtb20 in ventricular zone of MP appears to translate early positional information for establishment of all developing MP fields. Our data also suggest that the signaling factor Wnt3a is a putative molecular partner of TF Zbtb20 in this patterning process. © 2012 Wiley Periodicals, Inc.
Moving towards universal coverage with malaria control interventions: achievements and challenges in rural Burkina Faso
Authors: De Allegri Manuela , Louis Valérie R , Tiendrébeogo Justin , Souares Aurelia , Yé Maurice , Tozan Yesim , Jahn Albrecht , Mueller Olaf
Published: June 2012

This paper reports on a study, which assessed coverage with malaria control interventions in rural Burkina Faso, namely insecticide‐treated mosquito nets (ITN) ownership, intermittent preventive treatment (IPTp) for pregnant women and artemisinin‐based combination therapy (ACT) for under‐five children. The study also addressed the distributional impact of such interventions, with specific reference to equity. The study used data from a representative household survey conducted on 1106 households in the Nouna Health District in 2010. Findings indicated that 59% of all households owned at least one ITN, 66% of all pregnant women received IPT at least once and 34% of under‐five children reporting a malaria case were treated with ACT. Multivariate logistic regression revealed that higher socio‐economic status, ownership of at least one radio and living in a village within a Health and Demographic Surveillance System were significantly positively associated with ITN, IPTp and ACT coverage. ITN coverage was higher among households in villages, which had previously hosted an ITN trial and/or the most favourable arm of a trial. Comparing current findings with previous estimates suggests that the country has made substantial progress towards scaling up malaria control interventions but that current coverage rates are still far from achieving the universal coverage targets set by the Roll Back Malaria Partnership. In addition, current coverage patterns reveal the existence of multiple inequities across groups, suggesting that current policies are inadequate to achieve equitable scaling up. Future planning of malaria control interventions ought to take into consideration current inadequacies and lead to programmes better designed to overcome them. Copyright © 2012 John Wiley & Sons, Ltd.
Screening trial of human papillomavirus for early detection of cervical cancer in Santiago, Chile
Authors: Ferreccio Catterina , Barriga María Isabel , Lagos Marcela , Ibáñez Carolina , Poggi Helena , González Francisca , Terrazas Solana , Katki Hormuzd A. , Núñez Felipe , Cartagena Jaime , Van De Wyngard Vanessa , Viñales Daysi , Brañes Jorge
Published: June 2012

Cervical cancer mortality in Chile is four times higher than in developed countries. We compared the accuracy of human papillomavirus (HPV) DNA testing and conventional Papanicolaou (Pap) testing to detect prevalent precancerous and cancerous lesions in the routine clinical practice of the public health system. Women aged 25 years and older residing in the area covered by three primary care centers of Santiago, Chile, were invited to participate. Eligible women received both HPV DNA (Hybrid Capture 2) and Pap testing. Women positive by either test (Pap: ASCUS+, HC2: RLU/CO ≥1.0) underwent colposcopy and biopsy, as did a sample of double‐negative women with an abnormal cervix at visual inspection or with risk factors for cervical lesions. Crude and verification bias‐corrected sensitivities and specificities were estimated. In total, 8,265 women (98.8% of eligible) had complete screening results. Of these, 10.7% were HPV positive, 1.7% were Pap positive and 1.1% were positive by both tests. In all, 931 (11.3%) women were screen‐positive, of whom 94.3% attended colposcopy. Additionally, 295 control women were invited for colposcopy, of whom 78% attended. In all, 42 CIN2, 45 CIN3 and 9 cancers were identified. Verification bias‐corrected sensitivity for CIN2+ (95% confidence interval) was 92.7% (84.4–96.8) for HPV and 22.1% (16.4–29.2) for Pap; corresponding specificities were 92.0% (91.4–92.6) and 98.9% (98.7–99.0). In conclusion, in routine clinical practice in a developing country, HPV testing was four times more sensitive for CIN2+ than Pap testing, identifying three times more CIN2+ lesions; HPV testing was easily implemented in our established cervical cancer prevention program.
Autophagic tumor stroma: Mechanisms and roles in tumor growth and progression
Authors: Zhao Xianda , He Yuyu , Chen Honglei
Published: June 2012

Macroautophagy (hereafter autophagy) is a cellular homeostatic mechanism that involves protein and organelle degradation, and has a number of connections to human physiology and diseases. Autophagy in tumor parenchyma acts as either a tumor‐promoting role or a tumor‐inhibiting role depending on the types and stages of tumors. In recent years, attention to autophagy in tumor stroma that is referred as “autophagic tumor stroma” has created a new paradigm to understand the role of autophagy in cancer. Here we propose that the autophagic tumor stroma is a phenomenon of adaptation at a certain stage of tumor development, and has a prominent role in tumor growth, progression and spread of tumors. This idea is supported by recent studies: (i) Autophagic tumor stroma is activated by hypoxia and cancer cells induced oxidative stress, when tumors grow to a certain stage; (ii) Autophagic tumor stroma aids in providing essential nutrients to malignant cells, remodeling the tumor microenvironment, increasing DNA damage, genetic instability and stemness in cancer cells, and decreasing the apoptotic sensitivity of cancer cells. The autophagic tumor stroma is therefore a significant determinant in tumor growth and progression and implicates an important target for cancer therapies.
Influence of fatty acid‐free diet on mammary tumor development and growth rate in HER‐2/neu transgenic mice
Authors: Rossini Anna , Zanobbio Laura , Sfondrini Lucia , Cavalleri Adalberto , Secreto Giorgio , Morelli Daniele , Palazzo Marco , Sommariva Michele , Tagliabue Elda , Rumio Cristiano , Balsari Andrea
Published: June 2012

Numerous investigations have found a relationship between higher risk of cancer and increased intake of fats, while results of clinical studies of fat reduction and breast cancer recurrence have been mixed. A diet completely free of fats cannot be easily administered to humans, but experimental studies in mice can be done to determine whether this extreme condition influences tumor development. Here, we examined the effects of a FA‐free diet on mammary tumor development and growth rate in female FVB‐neu proto‐oncogene transgenic mice that develop spontaneous multifocal mammary tumors after a long latency period. Mice were fed a fatty acid‐free diet beginning at 112, 35, and 30 days of age. In all these experiments, tumor appearance was delayed, tumor incidence was reduced and the mean number of palpable mammary tumors per mouse was lower, as compared to standard diet‐fed mice. By contrast, tumor growth rate was unaffected in mice fed the fatty acid‐free diet. Plasma of mice fed the fatty acid‐free diet revealed significantly higher contents of oleic, palmitoleic and 20:3ω9 acids and lower contents of linoleic and palmitic acids. In conclusion, these findings indicate that a FA‐free diet reduces tumor incidence and latency but not tumor growth rate, suggesting that a reduction in dietary FAs in humans may have a protective effect on tumorigenesis but not on tumors once they appear. J. Cell. Physiol. 228: 242–249, 2013. © 2012 Wiley Periodicals, Inc.
Surfactant roles in modern sample preparation techniques: A review
Authors: Moradi Morteza , Yamini Yadollah
Published: June 2012

The pressure to decrease organic solvent usage in laboratories is increasing. Thus miniaturization and improvement of sample handling using alternatives is a challenge that has been discussed by several researchers. From this perspective, surfactant‐based sample preparations were an educated choice. Since the introduction of cloud point extraction by Watanabe, considerable studies have been focused on the chemical properties of surfactants in the extraction methods. The unique properties of surfactants make them flexible agents for different miniaturized sample preparation techniques based on solid‐ or liquid‐phase extraction. As a result, the use of surfactants with different roles in sample‐preparation methodologies (such as surfactant as an emulsifier, surfactant rich phase as an extraction medium, ion pair‐based extraction, hemimicelle/admicelle extraction, surfactant‐coated magnetic nanoparticle, solid‐phase microextraction with micellar desorption) is an important contribution to minimizing the problems arising from preliminary operations, which are the weakest step in analytical measurement. This paper reviews the literature dealing with the application of surfactant‐based sample preparations to the separation and the preconcentration of organic and inorganic species.
Nerve allografts supplemented with schwann cells overexpressing glial‐cell‐line–derived neurotrophic factor
Authors: Santosa Katherine B. , Jesuraj Nithya J. , Viader Andreu , MacEwan Matthew , Newton Piyaraj , Hunter Daniel A. , Mackinnon Susan E. , Johnson Philip J.
Published: June 2012

Introduction:

We sought to determine whether supplementation of acellular nerve allografts (ANAs) with Schwann cells overexpressing GDNF (G‐SCs) would enhance functional recovery after peripheral nerve injury.

Methods:

SCs expanded in vitro were infected with a lentiviral vector to induce GDNF overexpression. Wild‐type SCs (WT‐SCs) and G‐SCs were seeded into ANAs used to repair a 14‐mm nerve gap defect. Animals were harvested after 6 and 12 weeks for histomorphometric and muscle force analysis.

Results:

At 6 weeks, histomorphometry revealed that ANAs supplemented with G‐SCs promoted similar regeneration compared with isograft at midgraft. However, G‐SCs failed to promote regeneration into the distal stump. At 12 weeks, ANAs with G‐SCs had lower maximum and specific force production compared with controls.

Conclusions:

The combined results suggest that consistent overexpression of GDNF by G‐SCs trapped axons in the graft and prevented functional regeneration. Muscle Nerve, 2013
A generalized BEC picture of superconductors
Authors: Grether M. , de Llano M. , Tolmachev V. V.
Published: June 2012

A recent re‐examination of BCS theory leads one to devise a generalized BEC formalism (GBEC), that is, essentially a boson‐fermion (BF) model containing three new ingredients: (i) Cooper pairs (CPs), in contrast to BCS pairs, as real bosons; (ii) BF vertex interactions (analogous to electron‐phonon vertices); and (iii) two‐hole CPs (2hCPs) accounted for along with two‐electron CPs (2eCPs). In addition to the usual normal phase at high‐enough temperaturesT, three condensed phases emerge at lower temperatures with substantially higherTcs than BCS theory. These are: two pure BEC phases of 2eCPs and of 2hCPs as well as a mixed phase with both kinds of CPs. BCS theory is precisely recovered with a mixed phase of equal numbers of both kinds of CPs. In contrast to the well‐known BCS exponential rise from zero ofTcas function of carrier‐number density the GBEC scheme exhibits the linear rise as function of doping as eminently observed in high‐Tcunderdoped superconductors such as YBCO. © 2012 Wiley Periodicals, Inc.
Experiment and theory combine to produce a practical negative ion calibration set for collision cross‐section determinations by travelling‐wave ion‐mobility mass spectrometry
Authors: Hamilton Jenna V. , Renaud Justin B. , Mayer Paul M.
Published: June 2012

RATIONALE

There are relatively few cross‐section measurements for negatively charged ions. Available calibrants provide sufficient cross‐section coverage for the 390 Å2 to 641 Å2 and 1174 Å2 to 3395 Å2 ranges. This is not particularly well suited for determining the collision cross‐sections of smaller ions, such as small peptides.

METHODS

Molecular mechanics/molecular dynamics (MM/MD) simulations, coupled with simulated annealing, were used to find the low‐energy molecular conformations of polystyrene (PS) oligomers of length 3–9 (singly deprotonated) and 5–13 (doubly deprotonated). The trajectory method in MOBCAL was employed to derive their respective collision cross‐sections, Ω. A calibration plot relating corrected Ω values to drift times in a Waters Synapt G2 mass spectrometer was used to predict the Ω values for the −2 to −6 charge states of dT10 DNA.

RESULTS

The in silico design of a reliable negative ion calibration set for ion mobility spectrometry successfully resulted in the use of α,ω‐carboxy‐terminated PS oligomers to determine the collision cross‐sections of negatively charged ions in the range 132–388 Å2. All charge states of dT10 DNA were predicted to within 3% of the referenced values for these ions.

CONCLUSIONS

α,ω‐Carboxy‐terminated PS oligomers were found to be an excellent choice to calibrate ion mobility spectrometers to obtain cross‐sections for moderately sized ions. Oligomers with fewer, or weaker, interactions among the internal side chains (like poly(ethylene glycol) oligomers) tend to have a wide range of low‐energy molecular conformations resulting in large standard deviations in their theoretically predicted collision cross‐sections. Copyright © 2012 John Wiley & Sons, Ltd.
Ultrafast X‐ray sources for time‐resolved measurements
Authors: Hada Masaki , Matsuo Jiro
Published: June 2012

Extremely short pulse X‐ray sources have attracted considerable attention for unique use in time‐resolved X‐ray scattering, absorption, and diffraction measurements to investigate the molecular dynamics of chemical reaction in real time. The characteristics of X‐ray sources based on accelerators and femtosecond lasers are reviewed from the viewpoints of the X‐ray photon energy, pulse duration, intensity and stability of the pulses, and usability of the source. The X‐ray generation mechanism of each of the source is discussed from both the experimental and theoretical bases. We also demonstrate the application of ultrafast X‐ray diffraction measurements in the phase transition of vanadium dioxide using the laser‐induced plasma X‐ray source. The series of real‐time structural observations with pulsed X‐ray sources contributes toward understanding the mechanism of photo‐induced nonequilibrium process. Copyright © 2012 John Wiley & Sons, Ltd.
La[AsO3]: Lanthanum Oxoarsenate(III) with K[ClO3]‐Type Crystal Structure
Authors: Metzger Sebastian J. , Heymann Gunter , Huppertz Hubert , Schleid Thomas
Published: June 2012

Colorless, transparent single crystals of the lanthanum oxoarsenate(III) La[AsO3] emerged after exposing an equimolar mixture of La2O3 and As2O3 to high pressure (11.5 GPa) and high temperature (1000 °C). The air‐ and water‐stable compound crystallizes isotypically with K[ClO3] and thus can be described in the monoclinic space group P21/m with the lattice constants a = 442.91(4), b = 531.40(5), c = 622.83(6) pm and β = 105.564(3)° for Z = 2. Just like the K+ cations in K[ClO3], the crystallographically unique La3+ cations in La[AsO3] are surrounded by nine oxygen atoms (d(La3+–O2–) = 254–287 pm). The corresponding [LaO9]15– polyhedra get first interconnected by two edges to form infinite $\rm^{1}_{\infty}${[LaO7]11–} chains running along the a axis. These chains generate $\rm^{1}_{\infty}${[LaO6]9–} layers spreading out parallel to the ab plane by vertex‐sharing, which are further connected along [001] by common edges to build double layers. The(O1)2– anions remain terminal and protrude from these double layers in c direction, but finally serve for their condensation in order to erect a three‐dimensional anionic $\rm^{1}_{\infty}${[LaO3]3–} network. Charge compensation is achieved by incorporation of As3+ cations in creating isolated, ψ1‐tetrahedral [AsO3]3– units (d(As3+–O2–) = 176–177 pm, [ang](O–As–O)= 96–99°). Their lone pairs align along the c axis targeting at opposing La3+ cations.
A longitudinal study of the associations among adolescent conflict resolution styles, depressive symptoms, and romantic relationship longevity☆
Authors: Ha Thao , Overbeek Geertjan , Cillessen Antonius H.N. , Engels Rutger C.M.E.
Published: June 2012

This study investigated whether adolescents’ conflict resolution styles mediated between depressive symptoms and relationship longevity. Data were used from a sample of 80 couples aged 13–19 years old (Mage = 15.48, SD = 1.16). At Time 1 adolescents reported their depressive symptoms and conflict resolution styles. Additionally, time until break‐up was assessed. Data were analyzed using actor–partner interdependence models. Results showed no support for conflict resolution styles as mediators. Girls’ depressive symptoms were directly related to shorter relationships. Additionally, actor effects were found indicating that boys and girls with more depressive symptoms used negative resolution styles and were less likely to employ positive problems solving strategies. Finally, one partner effect was found: girls’ depressive symptoms related to more positive problem solving in boys.
Adult and adolescent social reciprocity: Experimental data from the Trust Game
Authors: Belli Stefano R. , Rogers Robert D. , Lau Jennifer Y.F.
Published: June 2012

Twenty‐four adults (aged 19–35) and 27 adolescents (aged 13–14) played as ‘Trustee’ in an iterated Trust Game against a pre‐programmed set of ‘Investor’ moves, said to belong to an unknown co‐player. Trustee behaviour was examined first in response to normative Investor cooperation, and then in response to a period of social rupture caused by reduced investments. Adolescents were motivated by inequity aversion during normative Investor cooperation, whereas adults over‐compensated the Investor. Participants were also identified as coaxers or non‐coaxers based on how they responded to social rupture: ‘coaxers’ were individuals who made at least one relatively generous return to the Investor during this phase. A single coaxing move predicted consistently higher returns to Investors across both normative and reduced investments. Adults showed greater polarisation between coaxing and non‐coaxing strategies than did adolescents. These data suggest that adults and adolescents may respond differently to periods of possible social rupture.
Comparison of misoprostol‐only and combined mifepristone–misoprostol regimens for home‐based early medical abortion in Tunisia and Vietnam
Authors: Blum Jennifer , Raghavan Sheila , Dabash Rasha , Ngoc Nguyen thi Nhu , Chelli Héla , Hajri Selma , Conkling Kathryn , Winikoff Beverly
Published: June 2012

Objective

To assess the potential advantages of combined mifepristone–misoprostol versus misoprostol‐only for early medical abortion.

Methods

A double‐blind randomized placebo controlled study was conducted that enrolled 441 pregnant women (< 63 days since last menstrual period) at 2 hospitals in Tunisia and Vietnam. The mifepristone–misoprostol group (n = 220) received 200 mg of mifepristone on day 1 and 800 μg buccal misoprostol followed by placebo 3 hours later on day 2. The misoprostol‐only group (n = 221) received placebo on day 1 and 1600 μg of misoprostol (2 doses of 800 μg, given 3 hours apart) on day 2. All medications were self‐administered at home with follow‐up 1 week later. The primary outcome was complete uterine evacuation without surgical intervention.

Results

Successful uterine evacuation occurred for 78.0% (n = 170) of women with misoprostol only versus 92.9% (n = 195) of women with mifepristone–misoprostol (relative risk 0.84, 95% CI, 0.78–0.91; P < 0.001). Ongoing pregnancy occurred for 13.8% (n = 30) of women given misoprostol‐only and 1.4% (n = 3) of women given mifepristone–misoprostol (relative risk 9.63, 95% CI 2.98–31.09; P < 0.001).

Conclusion

Mifepristone plus misoprostol is significantly more effective than misoprostol‐only for early medical abortion.

Clinical trials.gov registration number: NCT00680394.
Multi-proxy evidence for late Holocene anthropogenic environmental changes at Bongpo marsh on the east coast of Korea
Authors: Park Jungjae , Yu Keun Bae , Lim Hyoun Soo , Shin Young Ho
Published: June 2012

We present a multi-proxy record (pollen, microscopic charcoal, magnetic susceptibility, carbon-isotopic composition, total organic carbon [TOC], carbon/nitrogen [C/N] ratios, and particle size) of the late Holocene environmental change and human activities from Bongpo marsh on the east coast of Korea. Mutual interaction between the environment and humans during the late Holocene has not been properly investigated in Korea due to the lack of undisturbed samples with high sedimentation rates. In this study, the history of human responses to late Holocene environmental changes is clearly reconstructed using a multi-proxy paleoenvironmental approach that has not previously been applied in Korea. The evidence from Bongpo marsh indicates that 1) Bongpo marsh began to develop ca. 650 BC as a coastal lagoon was rapidly filled with organic matter, 2) agricultural disturbance around the study site remained slight until ca. AD 600, 3) full-scale intensive agriculture prevailed and the area of deforestation increased between ca. AD 600 and ca. AD 1870, and 4) the land use changed from lowland rice agriculture to upland cultivation when agricultural productivity declined after AD 1870, probably due to severe deforestation and the consequent heavy influx of clastic sediment on rice fields, as described in various historical documents.
II. An Experiment in Marine Fish Cultivation: II. Some Physical and Chemical Conditions in a Fertilized Sea-loch (Loch Craiglin, Argyll)
Authors: Orr A. P.
Published: June 2012

The dependence of plant production in the sea on the presence of nutrient salts, especially nitrate and phosphate, and on illumination has been repeatedly demonstrated. The object of the present work was to find primarily whether, and to what degree, plant and animal production could be increased by adding fertilizers to an enclosed body of sea water under otherwise natural conditions.
Hutton on Arran
Authors: Tyrrell G. W.
Published: June 2012

In 1899 Sir Archibald Geikie edited and published the third volume of Hutton's Theory of the Earth. The two earlier volumes had been published as far back as 1795. In his preface Sir A. Geikie gives the history of the MS. from which the present volume was printed; and he provides at the end of the work not only an index of Vol. III, but also, and separately, a most valuable index of the two earlier volumes, in which we note three references to Arran. In Vol. Ill, however, the last and longest chapter is devoted to “An Examination of the Mineral History of the Island of Arran” (pp. 191–267).
Inheritance of Resistance to Blight (Phytophthora infestans) in Potatoes: Strain C and its Relationships
Authors: Black William
Published: June 2012

Synopsis

The common strain A of the blight fungus (Phytophthora infestans) and two new strains, B and C, have been employed in testing potato varieties and seedling progenies, bred from the wild species S. demissum, for resistance to the disease. The reactions of seedlings to infection with strain C are compared with those of strains A and B. The C strain is shown to be more virulent than A, since it attacks some A resistant as well as all A susceptible plants. Likewise the B strain is more virulent than A. The difference between the pathogenicity of strains B and C, however, is not one of degree of virulence; one plant may be B resistant-C susceptible, while another may be B susceptible-C resistant. This difference is essentially of a qualitative nature. Resistance to these strains, which is manifested by the hypersensitive condition of the plant's cells, is produced in the presence of three major independent genes, Re, Rb and Rbc, which confer resistance to strains A and C, A and B, and A, B and C respectively. Segregations in each case are similar in type, and are characterised by an excess of recessive individuals.
Note on the Feeding of Amphioxus (Branchiostoma bermudœ)
Authors: Dennell R.
Published: June 2012

Synopsis

The ciliary feeding mechanism of Amphioxus (Branchiostoma bermudœ) is dependent for its continued effectiveness on the cleaning action of a powerful current of water produced by movements of the floor of the atrium. As ciliary feeding progresses, the buccal cirri become heavily choked with particles of detritus, and the feeding current entering the pharynx is thereby reduced. When this occurs, the atrial floor is violently raised and lowered, and water is pumped in and out of the atrium by way of the pharynx and oral hood, dislodging the accumulated particles from the buccal cirri. As is to be expected, the atriopore is capable of being closed during this process.
IX.—Examples of Hybridization between two Species of Macaw (Ara)
Authors: Auber L. , Osman Hill W. C.
Published: June 2012

Synopsis

The colour-pattern of hybrids between Ara chloroptera male and Ara ararauna female (Aves, Psittaci) combines parental features with a character which is found in some more “primitive” species of the genus but does not occur in the two parent species. The anatomical significance of this “ancestral” pattern mark is discussed.
XX.—The Floral Meristem as a Reaction System
Authors: Wardlaw C. W.
Published: June 2012

Synopsis

Floral ontogenesis has long been a preoccupation of morphologists. In trying to understand the physiological mechanism that underlies and determines the orderly formation of the several kinds of floral organs, it is essential to consider the organization and functional activities of the apex of the antecedent leafy shoot. The most general characteristic of the growing shoot apical meristem is that it gives rise to a succession of regularly spaced leaf primordia, sometimes of very variable form and structure, these having their inception in loci of special metabolism, or growth centres. The latter, typically originate in the sub-distal region of the meristem. The initial state of this region, which consists of equivalent embryonic cells, may be such that the reacting metabolic substances are homogeneously distributed in it. A contemporary chemical theory of morphogenesis envisages the possibility that a reaction system of this kind, in obedience to the laws of physical chemistry and mathematics, and on being activated, can give rise to a patternized distribution of metabolites, e.g. of growth centres, this constituting the chemical basis for the ensuing morphogenetic developments. This general property of the apex is maintained throughout the flora development, however much it may be modified in other ways. It is also known that the positions of new primordia are affected by those already present round the meristem.
III.—A Gravity Survey of a Glacier-dammed Lake in North Greenland
Authors: Bull C.
Published: June 2012

Synopsis

A gravity survey has been made of a glacier-dammed lake in Dronning Louise Land, North-East Greenland. Corrections for the effect of the local topography and the regional Bouguer anomaly are made to the values of the acceleration due to gravity measured at about 230 points on the lake and its shores. From the differences between the corrected values at the lake stations and those of the shores, depths of water under the lake stations are calculated, and a contour map of the lake bottom is drawn. A submerged shelf, 75 metres below the present lake level, persists around the western part of the lake. This may be the shore-line of a pre-glacial lake.
VI.—Maturation and Fertilization in Two Digenetic Trematodes, Haplometra cylindracea (Zeder 1800) and Fasciola hepatica (L.)
Authors: Sanderson Ann R.
Published: June 2012

Some time ago, in a short article on maturation in the liver fluke Fasciola hepatica (L.), Sanderson (1953) suggested that development might be gynogenetic on the grounds that she was unable to find any second maturation division nor any polar bodies. Nevertheless, the presence of two large “pronuclei” seemed to point to normal zygogenesis. Unable to come to any definite conclusion the author decided to investigate maturation in another digenetic trematode, Haplometra cylindracea (Zeder 1800) when ample supplies came to hand from class dissections of frogs.
XIV.—New Records of Polychætes from Scottish Coastal and Offshore Waters
Authors: McIntyre A. D.
Published: June 2012

Synopsis

From a faunistic survey in Scottish waters, concentrated mainly in the sea lochs of the north-west coast and in the deep water in the North Sea off the east coast, thirty-two species of polychætes are listed which have not previously been recorded from these areas. Seven of the species are new records for British coastal waters or for the North Sea.
V.—Genetics of Gametes. V. The Frequency Distribution of the Head Length of Rabbit Spermatozoa, and a Search for Dimorphism
Authors: Beatty R. A.
Published: June 2012

Synopsis

The possible effect of genes on the spermatozoa carrying them can be investigated by searching for two kinds of spermatozoa in the semen of heterozygous males. During the development of appropriate biometrical methods, it became desirable to specify more exactly the basic form of variation in size between spermatozoa sampled from the same ejaculate and mounted on the same nigrosin-eosin preparation. The present study of the head length of rabbit spermatozoa indicates that apart from rare spermatozoa with exceptional dimensions the variation of spermatozoa on a preparation follows almost completely a “normal” distribution, the variance being independent of the mean and homogeneous from one preparation to another. The coefficients of skewness (g1) and of kurtosis (g2) and the statistic k4, average close to zero, g2 and k4 being homogeneous between preparations. There is evidence of heterogeneity in skewness between preparations, but the reality of the heterogeneity is not quite certain. A potential dimorphism between spermatozoa bearing X- and Y-chromosomes is inherent in the material, but analysis showed no significant evidence of any dimorphism in head length.
VI.—Genetics of Gametes. VI. Attempted Genetic Transformation in the Rabbit
Authors: Beatty R. A. , Billett F. S.
Published: June 2012

Synopsis

Genetic transformation in the rabbit has been attempted by the artificial insemination of semen incubated with deoxyribonucleic acid. No evidence was obtained of any transformation at the albino or rex loci, nor of sex. The experiments comprised twenty inseminated does, and 133 offspring of several categories.
XVII.—Embryogenesis and Larval Organs of the Giant Land Snail Achatina fulica Bowdich
Authors: Ghose Krishna Chandra
Published: June 2012

Synopsis

Organogenesis is completed by 15 days. A modified veliger stage is present. Torsion begins at about the sixth day. The foot rudiment is first to appear. The stomodæum appears as a new structure. The salivary glands develop from the stomodæum by evaginations. The œsophagus is stomodæal, while the crop and the primitive stomach are archenteric in origin. The digestive gland develops as two outgrowths of the primitive stomach. The hind gut is formed by the cells proliferated from the closed posterior end of the archenteron. It opens into the primitive stomach in a 2·5 mm. embryo, and the anus appears very late. The proctodæum is absent. The primordium of the pericardium with the heart, definitive kidney and gonad is mesodermal. The ureter is ectodermal and arises from the mantle cavity by evagination and subsequently communicates with the kidney. Lung and mantle are ectodermal and arise by separate invaginations. The lung fuses with the mantle and loses its separate existence from about a 4 mm. embryo. The nervous system is early to appear and the sense organs, except the statocysts are late in origin. They are ectodermal. The larval organs are: velum, podocyst, larval kidney, nuchal cells and larval digestive gland. The prototroch is the rudiment of the velum. It appears in a very early embryo from the posteroventral part and marks off the anterior border of the stomodæum. The cells of the prototroch become hyaline, vacuolate and develop cilia in a 2·25 mm. embryo, and it is transformed into velum. The velum helps in driving albumen into the larval and adult digestive glands and is resorbed in the body-wall epithelium. The rudiment of the foot first appears after the completion of gastrulation, and the podocyst is differentiated from it later. It steadily increases in size, assumes a hood-like shape, exhibits contraction and relaxation movements and begins to reduce when the embryo attains 3·25 mm. size. It is completely resorbed in the foot. The larval kidneys are mesodermal in origin, appear, in a 920 μ embryo. They begin to degenerate after the formation of the functional definitive kidney and disappear in a late larva. The kidneys are U-shaped, the cells of the closed anterior and bear pseudopodia, which are almost totally replaced by cilia afterwards. The kidney opens to the exterior posteriorly. The cells become vacuolated and excretory granules accumulate in the vacuoles. The nuchal cells first appear in a 2·5 mm. embryo and are excretory. They increase both in number and size with the growth of the embryo and persist throughout the larval period. The endoderm cells of the major portion of the archenteron except a small posterior part, enlarge in size, develop vacuoles and form a larval digestive organ for the purpose of digestion of albumen. Even after the formation of the adult digestive gland, the larval digestive gland functions for a short time, then degenerates and disappears at the end of the larval life.
III.—On the Relationships of Certain Carboniferous Dipnoi; with Descriptions of Four New Forms
Authors: Thomson Keith Stewart
Published: June 2012

Synopsis

The Lower Carboniferous genus Prosagenodus Romer and Smith 1934 is re-examined. The type species Prosagenodus interruptus is re-assigned to the genus Ctenodus and a new genus Tranodis named for the American species, of which new material is described. The new species Ctenodus romeri is described, the new genus Straitonia is described, and the bearings of all these discoveries upon consideration of the phylogenies of Ctenodus and Sagenodus is discussed.
III.—The Response of Human Motor Nerve to Rectangular Electric Pulses Applied Through Electrodes Placed on the Skin
Authors: Stephens W. G. S.
Published: June 2012

Synopsis

The passive electrical impedance characteristics exhibited by the body during rectangular pulse stimulation are analysed, and typical observed properties are specified in terms of the parameters of an equivalent electrical circuit. Equations are derived which describe the current waveform generated in such a circuit by a rectangular pulse stimulator of known finite output impedance. The response of nerve to currents of this form is analysed, and equations are derived which permit the comparison of threshold and intensity-duration data obtained with stimulators of different output impedances. Results predicted by the theory are shown to be in good agreement with experimental results.
XVIII.—Histochemical Studies of Keratin Fibres
Authors: Stoves J. L.
Published: June 2012

During a study of the micro-structure of keratin fibres (Stoves, 1944) it was found that certain members of the Mustelidæ,e.g.kolinsky (M. Sibirica), ermine (M. erminœ), and Jap mink (M. itatsi), possess primary hairs with well-developed cuticle, cortex, and medulla. In the case of rabbits and hares (Leporidæ), however, the corresponding fibres are composed almost entirely of medulla cells. The two types of fibres, therefore, provide suitable material for studying the chemical reactivity of the keratin constituting cuticle, cortex, and medulla of animal hair. Accordingly, the effect of various reagents upon transverse sections of fibres from the above-mentioned animals was examined, and a preliminary report of the results has already been made (Stoves, 1943a). A more detailed account of the work now appears.
XIX.—A Comparative Study of the Cytoplasmic Components of the Male Germ-Cells of Certain Mammals
Authors: Gresson R. A. R. , Zlotnik I.
Published: June 2012

The work recorded in this paper was undertaken in order to obtain further knowledge regarding the behaviour of the cytoplasmic components of the male germ-cells of mammals and the contribution made by these bodies to the structure of the ripe sperm. Consequently, mammals from different groups were examined.

Investigations were carried out independently by Zlotnik on the male germ-cells of the dog, the cat, and the rabbit, by Gresson on the boar and the ram, and jointly by Gresson and Zlotnik on the white rat and the golden hamster. Zlotnik (1943) originally identified and described the nuclear-ring of the spermatid and sperm of the dog. The accessory body was recognised simultaneously by him and by Gresson, but Zlotnik was the first to observe an accessory body within the localised Golgi material of the spermatocyte and to follow its extrusion to the cytoplasm, and, later, Gresson identified an accessory body within the Golgi material of the spermatid of the boar. In general the conclusions of the two authors are closely similar, such differences of detail or of interpretation as exist are discussed in this paper.
XXIII.—Infertility and Embryonic Mortality in the Domestic Fowl
Authors: Blyth J. S. S.
Published: June 2012

During the winter of 1937–38 it became necessary to obtain the maximum number of offspring from a certain pen mating for the purposes of an experiment unconnected with the present report. Accordingly all suitable eggs were incubated, and since chicks were required all the year round the data which accumulated related to periods extending beyond the normal hatching season. Not long after the beginning of the project strikingly consistent differences between the records of the individual females became apparent, and interest in this phenomenon led to the decision to incubate every intact egg from the pen, irrespective of any normally undesirable characteristics of shell texture or shape. This was done for two years (1938–39), and provided the main data for the study of fertility and embryonic mortality reported here.
XIV.—Rowett Research Institute
Authors: Cuthbertson D. P.
Published: June 2012

The Rowett Institute for research on animal nutrition had its origin under a scheme for promoting scientific research in agriculture adopted by the Development Commission in 1911.

The Governing Body, which originally consisted of an equal number of members appointed by the Court of the University of Aberdeen and the Governors of the North of Scotland College of Agriculture, was constituted in 1913. Within recent years it has been expanded to include persons nominated by the Secretary of State for Scotland, the Royal Society, the Royal Society of Edinburgh, the Agricultural Research Council, and the Medical Research Council. Research work was begun in temporary accommodation in Marischal College in 1914, under the direction of Dr John Boyd Orr—now Lord Boyd-Orr—who continued as Director until his retirement in 1945.
XXIII.—Sexual Maturity in Brown Leghorns. The Interactions of Genotype and Environment
Authors: Osborne Robert
Published: June 2012

Synopsis

In each of three years studied, the spring hatching period for a flock of Brown Leghorns has been divided into two sub-periods such that a number of matings are represented by offspring in each sub-period. Analysis of variance of age at sexual maturity reveals statistical interaction between family means and hatching period, the ranking of family means varying with date of hatch. Consequences of this are discussed with reference to current methods of correcting age at maturity for date of hatch, the method of multiple shift progeny testing, and the general question of improvement by selection in the presence of non-additive combinations of genetic and environmental effects.

Measurements of comb growth in maturing pullets reveal a seasonal retardation, possibly reflecting retardation in sexual maturity, and in line with environmental effects causing cessation of production in older birds. It is suggested that rapid changes in day length during September and October may play a large part in determining the retardtions and interactions displayed, and that measurements of comb growth may be of value in recognising consistently superior genotypes for age at sexual maturity.
XV.—Observations on the Development of the Proteus Group of Amœbæ
Authors: Taylor Monica , Hayes Catherine , Galbraith Mary
Published: June 2012

Synopsis

Details of what occurs in the interval between the hatching of amœbulæ from the spores of the Proteus group of amœbæ to the attainment of the adult condition (4–6 months) not hitherto known are described. The method consists in removing mature adults to petri dishes 4 in. in diameter, containing a dilute inorganic fluid which causes sporulation. The subsequent development of the hatching amœbulaæ can be traced in situ by means of a 4·4 mm. water immersion lens, and is seen to consist of feeding and growth alternating with periods of encystment. The time spent in cysts greatly exceeds that of activity.

Some account of what takes place when cultures of the Proteus group, allowed to dry to a brownish dust, and then wetted, is given. Only in the case of A. proteus have the amœbulæ, which hatch out from the spores, been grown to maturity. It has been shown that the dried cultures used may comprise (1) spores, (2) cysts of varying size from which arise amœbulæ likewise varying in size.
XXVI.—The Induction of Pregnancy in the Golden Hamster during the Breeding Pause
Authors: Peczenik O.
Published: June 2012

In 1930 ovulation in ferrets outside the breeding season was obtained by Hill and Parkes (1930) by means of gonadotrophic extracts. Later, similar results were obtained in sheep and thus it became possible to induce pregnancy outside the normal breeding season (Cole and Miller, 1933), and its practical importance was investigated by Parkes and Hammond (1940). Similar experiments on the golden hamster,Cricetus auratus, are described below, as this animal has proved to be a most interesting subject for the study of sex hormones (Klein, 1937 and 1938; Peczenik, 1942).
VI.—The Tumour Virus disseminated from Rous No. 1 Tumours
Authors: Carr J. G.
Published: June 2012

In common with other neoplasms, the Rous No. 1 tumour often shows small areas or even single cells that appear dead and disintegrating or moribund. These probably result from the interaction of such factors as inadequate vascularization, pressure, and the formation of non-viable cells as a result of abnormal mitosis. As death of the cell does not necessarily result in destruction of the tumour virus, the virus of such cells is presumably released into the host's tissues. There is some difference of opinion as to the part that this virus plays in extending the growth of the tumour by infecting neighbouring cells and by producing metastases (review in Foulds, 1934), but it is generally agreed that the virus is present in most tissues of an animal bearing a filterable tumour (Bürger, 1914; Fujinami and Suzue, 1925; Fränkel, 1927; Costa, 1932; Mellanby, 1935, 1936, 1937, 1938 a, 1938 b) without, however, producing any tumours. The reason for this absence of carcinogenic action on the part of the disseminated virus has remained obscure. It was also noted that recurring Rous tumours are always found at the sites inoculated with tumour material, and never result from disseminated virus (Carr, 1942). Mellanby (1938 b) noted that the amount at first increased and later decreased with time, no active virus being found forty or more days after the initiation of tumour growth in the host. A similar decrease in the amount of extractable virus in tumours has been described (Carr, 1943) and shown to be due to antibodies in the tissue fluid inactivating the virus as it is extracted from the tumour cells. This raised the possibility that virus was similarly present in the normal tissues of hosts bearing lasting tumours, though not demonstrable for the same reason. The present investigation was undertaken to see if this was the case, and to discover the reason for the absence of neoplastic action of such virus.