bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vertebrate Embryo: Neural Patterning
Authors: Itasaki Nobue 
Published: February 2015

AbstractNeural patterning is the process of providing regional identities in neural cells in accordance with their location in the neural tube. Allocation of regional identities is prerequiscent for the following processes of neuronal circuit formation. The neural tube is longitudinal among the body axis thus having anterior–posterior polarity (rostral–caudal in aves, future superior–inferior in adult human). It also has dorsal–ventral polarity and right and left sides. Neural patterning commences as the neural induction takes place progressively in the anterior to posterior direction. By signalling and tissue interaction, the neural tube is divided into the forebrain, midbrain, hindbrain and the spinal cord along the anterior–posterior axis. Further divisions follow to produce differentiation of functional compartments that are defined by the combinatorial expression of molecular markers. The same principle, the initial subdivision by signalling followed by refined compartmentalisation, applies to the acquisition of dorsal–ventral specification as well.Key ConceptDepending on the actual position in the body, cells are specified with respect to the position (positional specification), thus positional identity is acquired. Cells then interpret their positions to differentiate accordingly, thus spatial patterns are formed (see Wolpert, 2011).Neural patterning is the process through which neural progenitors acquire positional identities. The initial allocation of positional information is governed by signalling mechanisms. This is followed by expression of transcription factors, such asHoxgenes for the anterior–posterior axis.
Foot‐and‐Mouth Disease
Authors: Belsham Graham J , Charleston Bryan , Jackson Terry , Paton David J 
Published: February 2015

Abstract

Foot‐and‐mouth disease (
FMD
) is an economically important, highly contagious disease of cloven‐hoofed animals characterised by the appearance of vesicles (blisters) on the feet and in, and around, the mouth. The causative agent, foot‐and‐mouth disease virus (
FMDV
), was the first mammalian virus to be discovered. It has a ribonucleic acid (
RNA
) genome enclosed within a protein coat (capsid). The virus replicates very rapidly within the cytoplasm of cells. The
RNA
genome has to function both as a messenger
RNA
(
mRNA
) and as a template for
RNA
replication. The
RNA
encodes a single large polyprotein that is processed, by virus‐encoded proteases, to about 12 mature products (plus functionally important precursors) that are required for virus replication and assembly. Some of these viral proteins modify host cell activities to block antivirus defence systems. Thus, this small virus displays a remarkably complex array of biological activities.

Key Concepts

Foot‐and‐mouth disease has worldwide economic importance.

Foot‐and‐mouth disease virus (FMDV) is able to infect a wide range of different cloven‐hoofed animals.

Seven different serotypes of FMDV are known and there is considerable antigenic diversity within each serotype.

FMDV uses specific cell‐surface molecules (including specific integrins) as receptors to gain entry into cells.

The viral RNA is sufficient to initiate an infection.

The RNA displays diverse activities, as a messenger RNA, as a template for RNA replication and as the genome.

The virus‐encoded polyprotein is processed by proteases present within itself to make about 12 different mature products (plus important precursors).

Viral proteins are required both for viral RNA replication and virus assembly; in addition, some also modify specific cellular functions in order to block host antiviral responses.

Current vaccines rely on the production and then chemical inactivation of infectious virus.

Non‐infectious empty capsid particles can be produced, which are candidates as new, safer vaccines.
Lamins: Organisation, Dynamics and Functions
Authors: Zuela Noam , Gruenbaum Yosef 
Published: February 2015

AbstractLamins are evolutionary conserved nuclear intermediate filaments. They are the major component of a protein network, termed the nuclear lamina, which is located underneath the inner nuclear membrane of the nuclear envelope. A small fraction of lamins also localise throughout the nucleoplasm. Lamins are involved in most nuclear functions including mechanical stability, cytoskeletal organisation, genome stability, chromatin organisation, differentiation and tissue‐specific functions. During the past two decades, interest in lamins increased due to the discovery of over 450 missense mutations in the humanLMNAgene causing more than 15 different heritable diseases. These disorders are collectively known as nuclear envelopathies or laminopathies and range from muscular dystrophies to accelerated ageing disorders, affecting a range of different tissue types. Understanding lamins' structure, dynamics and functions is key in elucidating the elusive molecular mechanisms leading to these disorders.Key ConceptsThe nuclear envelope separates the nucleus from the cytoplasm and is composed of an outer nuclear membrane, an inner nuclear membrane, nuclear pore complexes and nuclear lamina.Lamins are the main components of the nuclear lamina.Unique features of lamins include a nuclear localisation signal (NLS), an immunoglobulin fold and a carboxyl tail CaaX (C = cysteine, a = aliphatic amino acid, X = any amino acid) motif.Lamins are grouped into A‐ and B‐type lamins based on their biochemical properties and behaviour during mitosis.Each metazoan cell expresses at least one B‐type lamin.Lamins are involved in most nuclear functions.In mammals, the A‐ to B‐type lamin ratio regulates the differentiation state of cells.Mutations in lamins can have dramatic effects on their higher order structures.Lamins interact with a plethora of proteins in the nuclear membrane and nucleoplasm.Mutations in human lamin genes, and especially theLMNAgene, cause over 15 distinct diseases effecting different tissues.
Infections in the Secondary Immunocompromised Host
Authors: Elliott Ivo , Venkatesan Pradhib 
Published: February 2015

Abstract

Deficiency in host defences allows infections to occur with greater frequency. Their nature and presentation may be unusual and hence diagnosis may be difficult. The type, severity and duration of immunocompromise determine the infections to which the host is vulnerable. Unlike in primary immunocompromised patients, the susceptibility of secondary immunocompromised patients often changes during the course of their illness as their immune function may vary with the use of immunosuppressive drugs or highly active anti‐retroviral agents prescribed for those with human immunodeficiency virus. There is an ever‐increasing number of new agents that modify the host immune response. These include biologic therapies that target specific cytokines and are used in various inflammatory disorders. The growing numbers of immunocompromised patients make this a key area for those involved in managing infections. A number of strategies are employed to combat the infectious threat ranging from prophylaxis to pre‐emptive, empirical and definitive treatment.

Key Concepts

Immunocompromised patients are susceptible to a range of opportunistic infections due to deficiencies in their immune defences.

Opportunistic infections occur in immunocompromised but not immunocompetent hosts.

Specific immune defects may predispose to a restricted range of opportunistic infections.

Immune defects may involve innate (antigen non‐specific) or adaptive (antigen specific) responses.

Clinical features may be modified or less apparent in the presence of immunodeficiency.

The diagnosis of an infection requires consideration of infectious exposures, details of immunodeficiency and all clinical features and investigation results.

Clinical illness may be prevented by screening and treating latent infection, prophylaxis or pre‐emptive treatment in the subclinical phase if markers of infection progression are available.
RNA
Structure: Tetraloops
Authors: Cheong Hae‐Kap , Kim Nak‐Kyoon , Cheong Chaejoon 
Published: February 2015

Abstract

RNA
hairpins are among the most common
RNA
secondary structural elements and are frequently capped by
RNA
tetraloops.
RNA
tetraloops are composed of characteristic four‐loop nucleotides that form a compact and stable structure. While they can be formed by many different nucleotide sequences,
UNCG
(N = A, C, G, or U),
GNRA
(R = A or G), and
CUUG
tetraloops are found most often. Tetraloops usually help initiate
RNA
‐folding processes and provide sites for tertiary contacts within or between
RNAs
and for protein binding, thereby facilitating the assembly of ribonucleoprotein particles. Tetraloop interactions can be either sequence‐ or structure‐specific. Herein, we discuss the structures of
RNA
tetraloops and their interactions with other
RNA
structural motifs and with
RNA
‐binding proteins.

Key Concepts

RNA hairpins play important structural and functional roles in RNA.

RNA tetraloops are composed of four‐loop nucleotides that form a compact and stable structure.

Tetraloops assist RNA folding and provide sites for RNA–RNA and RNA–protein interactions.

Tetraloop interactions can be either sequence‐ or structure‐specific.

We discuss the structures of RNA tetraloops and their interactions with other RNAs and proteins.
Eugenics
Authors: Paul Diane B 
Published: February 2015

AbstractThe term ‘eugenics’, coined in 1883 by Sir Francis Galton, refers to efforts to improve humanity through selective breeding. ‘Positive eugenics’ aims to increase the frequency of desirable traits in the population and ‘negative eugenics’ to decrease the frequency of negative ones. Although eugenics was once an international and widely supported movement, it was ultimately discredited as scientifically naïve and racially and class‐biased. Today, the word has highly pejorative connotations and is often equated with Nazi efforts to create a master race. However, there is disagreement over whether the use of prenatal diagnosis and other contemporary reproductive technologies constitutes a new eugenics, and in recent years, several scholars have also argued that eugenics' fundamental aim of human genetic improvement is laudable, even if earlier efforts to accomplish it were marred by coercive means, faulty science, and social prejudice.Key ConceptsIn the first three decades of the twentieth century, eugenics was a popular movement of international scope.Eugenicists assumed that most mental, moral, and personality traits were hereditarily transmitted from parent to offspring.In the United States, family pedigree studies conducted by eugenic field workers seemed to prove that many such traits followed a Mendelian pattern of inheritance.Eugenicists assumed that most social problems were due to bad heredity and that their solution lay in discouraging those with hereditary defects from breeding.American eugenicists were primarily concerned with mental deficiency or ‘feeblemindedness’ and British eugenicists with ‘hereditary pauperism’.Fear that the incidence of mental deficiency was increasing intensified in the wake of intelligence (IQ) testing, especially of US army recruits in World War I.In several countries, eugenicists viewed immigration from particular countries or regions as a primary threat to the biological quality of the population.There is much greater agreement on when modern eugenics began than on when or why it came to seem disreputable.Today, there is intense debate over whether prospective parents' voluntary use of reproductive genetic services constitutes a new, consumer‐driven eugenics.Recently, some commentators have argued that eugenics' core aim of human genetic improvement is defensible.
Compensatory Evolution in Disease‐Associated Genes
Authors: Azevedo Luisa 
Published: February 2015

Abstract

Genetic diseases are caused by amino acid replacements at functionally important positions of protein sequences. These positions are conserved at the interspecific level, indicating that their replacement would be expected to be deleterious between homologous sequences. However, several examples of human disease‐associated mutations have been found in the genomes of non‐human species. Following the model of compensatory evolution, the acceptability of human deleterious mutations in other species is strictly dependent on the presence of a compensatory partner variant that is able to compensate for the negative effect of the mutation. The co‐occurrence of a compensated mutation and its compensatory partner has now been documented for a large number of proteins involved in human genetic disease, thereby increasing theoretical and experimental support for the model of compensatory evolution at the same time as providing us with an improved understanding of the molecular and selective forces underlying the mechanism of amino acid interaction.

Key Concepts

A high number of human disease‐associated mutations are found in non‐human species.

Many human disease‐associated mutations are compensated in non‐human species by epistatic interactions with a compensatory variant.

The deleterious impact of a variant depends on the genetic background where it occurs.

The basis of molecular compensation results from the structural interaction between amino acid variants.
Life Sciences in China
Authors: Wang Yihuang , Wen Zhaojun , Chen Zhu 
Published: February 2015

Abstract

Modern life sciences have been introduced into China from the West for more than 170 years; however, the fast progress was only seen in the past three decades. How China feeds its people and keeps them healthy remains a mystery for many Westerners. Chinese life scientists have done their best to increase the yields of rice and other crops, and develop vaccines and treatments to combat the major diseases in China. Thanks to the fast growing economy, the Chinese government input in research and development was significantly increased and led to the great leap forward of life sciences in the past 30 years. The stories behind the past and present life sciences in China are permeated with legends, and they are worthwhile knowing.

Key Concepts

Life sciences in China are mainly supported by the government.

The Chinese government looks at life sciences as the driving force for sustainable economic growth.

Feeding the huge population and keeping the people healthy are the main challenges faced by Chinese life scientists.

The leap forward of genomics and the significant increase of government input led to the fast progress of life sciences in China.

Stem cell research and neuroscience are the fastest growing fields in China.
The Gene Content of Mammalian and Avian Sex Chromosomes
Authors: Bennett‐Baker Pamela , Mueller Jacob L 
Published: February 2015

Abstract

Sex chromosomes evolve specialised collections of genes, making them distinct from autosomes. Recent, high‐quality, genomic sequencing of sex chromosomes allows us to trace the evolutionary history of the mammalian X and Y chromosomes and avian Z and W chromosomes, and examine how evolution has remodelled their gene content. The
XY
and
ZW
sex chromosomes arose from ordinary pairs of autosomes. Differentiation into specialised sex chromosomes initiated with the degeneration of gene content on the Y and W chromosomes and the preservation of gene content on the X and Z chromosomes. As these degeneration and preservation processes unfolded, the sex chromosomes also acquired new genes, many of which are located in large, nearly identical, segmental duplications called amplicons. Ampliconic sequences, independently evolving across multiple lineages, are a major driving force in sex chromosome evolution.

Key Concepts

Mammalian and avian sex chromosomes evolved independently from autosomes.

X and Z chromosomes retain the majority of the ancestral autosomal genes.

X chromosome ancestral autosomal genes are highly conserved across mammals.

The gene content of Y and W chromosomes has degenerated.

Ampliconic sequences have independently evolved on X, Y, Z and W chromosomes.
Long Noncoding
RNA
s and Tumorigenesis
Authors: Matjašič Alenka , Glavač Damjan 
Published: February 2015

Abstract

In contrast to the long time, well‐established knowledge about the majority of human genome to be only ‘junk
DNA
’, it turned out that a great part of it is being pervasively transcribed. Among noncoding transcripts, long noncoding
RNA
s (
lncRNA
s) represent the most prevalent and functionally heterogeneous group of noncoding
RNA
s (
ncRNA
s). Despite only a few
lncRNA
s being well characterised, their biological meaning, mechanisms of function and their importance for normal development is being more and more recognised. Many studies in recent years have shown that the changes in
lncRNA
s expression and function are associated with some fundamental biological processes and various disease states, most notably cancer. In cancer, the function of
lncRNA
s shows through altered expression patterns in different tumour types and as such they represent potential diagnostic/prognostic biomarkers and new potential targets for cancer treatment.

Key Concepts

lncRNAs are important components of numerous biological pathways of cellular growth, cell division and differentiation.

lncRNAs directly or indirectly regulate the expression of protein‐coding genes on epigenetic, transcriptional and post‐transcriptional level.

Aberrant lncRNA expression leads to cell dysfunction and disease progression.

lncRNAs are potential drivers of various diseases, most notably of cancer.

They represent useful diagnostic biomarkers and indicators of patient's prognosis.

lncRNAs represent ideal candidates for targeted gene therapy.
Control of Axon Selection
Authors: Richter Melanie , de Anda Froylan Calderon 
Published: February 2015

Abstract

The term polarity is used to define asymmetry. In cell biology, it refers to describe the shape of a cell, the distribution of organelles, molecules and thus the intracellular trafficking of cellular components. How this asymmetry is attained in neurons is a question that has been under scrutiny as the shape of a neuron provides valuable clues to its function: Mature neurons extend dendrites and an axon to receive, process and propagate signals. A long‐standing question in neurobiology is how neurons decide where the axon would form. One possibility is that external cues determine the position of axon extension. However, it is also possible that the intracellular organisation of the neuron determines where the axon will grow. Existing data provide evidence for both mechanisms playing a role during the axon selection, either concomitantly and/or sequentially.

Key Concepts

Neurons are highly polarised cells with generally one axon and several dendrites.

Neurons developing
in vitro
form axons and dendrites, which resembles the
in vivo
situation.

Axon selection is the result of synchronous and/or sequential effects of intrinsic and extrinsic cues.
Stentor, Its Cell Biology and Development
Authors: Reiff Sarah B , Marshall Wallace F 
Published: February 2015

AbstractStentorcomprises a genus of freshwater protists that has long enthralled cell and developmental biologists. These organisms are large polyploid single cells that possess highly polarised and complex structures. Normally elongated in a trumpet‐like shape,Stentorcells also have the ability to contract their cell body, and do so in response to mechanical or light stimuli. Interestingly, this response is subject to habituation, meaning the cell can ‘learn’ after repeated exposure to ignore these stimuli and stay elongated. Perhaps the most remarkable characteristic ofStentoris the ability of these cells to fully regenerate after being cut in half, perfectly preserving the original cell structure. Numerous microscopic studies analysed the minute morphological details ofStentorregeneration, but for many decades, there were no tools available for molecular and genetic studies. However, recent developments should now allow researchers to probe the molecular details of regeneration in a single‐celled organism.Key ConceptsStentor coeruleusis a large and highly polarised single cell with complex cell biology.Stentor cells exhibit a rapid contractile response in reaction to light and mechanical stimulation, but they can habituate to these stimuli over time.Stentor cells possess the remarkable ability to fully regenerate themselves after being cut in half.
Choosing Your Words and Pictures Wisely: When Do Individuation Instructions Reduce the Cross‐Race Effect?
Authors: Pica Emily , Warren Amye R. , Ross David F. , Kehn Andre 
Published: February 2015

SummaryRecognition accuracy for faces of an individual's own race typically exceeds recognition accuracy for other‐race faces. The categorization–individuation model (Hugenberg, Young, Bernstein, & Sacco, 2010) attributes this cross‐race effect to motivation to encode distinctive features of own‐race faces but category defining features for other‐race faces. Two experiments using different stimuli tested hypotheses generated from this model with both Black and White participants. For White participants, instructions to individuate reduced the cross‐race effect in both studies but did not eliminate it in Study 1. Black participants did not exhibit the cross‐race effect in either study, but individuation instructions improved both their same‐race and other‐race sensitivity. The present quality of interracial contact moderated the relationship between instructions and other‐race sensitivity for both Black and White participants in Study 1 but not in Study 2. Overall, results provide mixed support for this social categorization model. Copyright © 2015 John Wiley & Sons, Ltd.
Gamma Radiation Induced Modifications on Physicochemical Properties of Makrofol (KG and N) Polycarbonate
Authors: Gupta Sanjeev Kumar , Singh Paramjit , Kumar Rajesh , Kumar Satyendra 
Published: February 2015

ABSTRACTMakrofol (KG and N) polycarbonates (PCs) are the most versatile solid‐state nuclear track detectors. These polymers were exposed to gamma radiation of doses ranging from 250 to 1000 kGy. The pristine and exposed samples were characterized by X‐ray diffraction (XRD), UV–vis spectrophotometry, and Fourier transform infrared spectrophotometry for the structural, optical, and chemical studies, respectively. The XRD studies showed that crystallite size for exposed samples of makrofol‐KG PC decreased from 64.7 to 57.9 Å and for makrofol‐N PC it increased from 19.1 to 21.1 Å. The band gap energy decreased from 4.40 to 4.07 eV for makrofol‐KG and from 4.26 to 3.83 eV for makrofol‐N after the gamma exposure. The number of carbon atoms per conjugation length as obtained from UV–vis studies was increased in both cases. The activation energy showed fluctuations for exposed samples of both polymers. The intensity of various absorption bands of the infrared spectra decreased at some doses for both the PCs, indicating the change in the chemical properties of the exposed samples.
Cardiopulmonary arrest during the Nuss procedure: case report and review
Authors: Nakahara Osamu , Ohshima Shigeki , Baba Hideo 
Published: February 2015

CaseThe Nuss procedure is an established and widely approved minimally invasive technique for the correction of pectus excavatum. However, patients undergoing the procedure are at increased risk of cardiac arrest. It has not been established whether cardiopulmonary resuscitation is possible in patients who have received the Nuss procedure. We present here the case of a 14‐year‐old boy with pectus excavatum who underwent minimally invasive pectus repair but later had a fatal cardiac event before pectus bar removal.OutcomeBystander cardiopulmonary resuscitation was carried out immediately but resuscitation failed.ConclusionIn patients who have undergone the Nuss procedure for pectus excavatum, it is important to manage perioperative events such as arrhythmia, develop measures for managing emergency situations in patients' areas of residence, and carry out continuing research and development of medical supply materials that can be used to manufacture Nuss bars.