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Neurogastroenterology and Motility Jul 2023The Chicago classification primarily utilizes ten 5 mL liquid swallows in a supine position as the standard high-resolution esophageal manometry (HRM) protocol. HRM...
BACKGROUND
The Chicago classification primarily utilizes ten 5 mL liquid swallows in a supine position as the standard high-resolution esophageal manometry (HRM) protocol. HRM can be performed with varying volumes and consistencies and in an upright position. We aimed to determine the impact on HRM results by (1) position, (2) swallows of differing volume and consistency, and (3) perception of bolus passage.
METHODS
HRM was performed in healthy volunteers (HV) with the following protocol of swallows: liquids 10 × 5 mL, 5 × 10 mL, and 3 × 10 mL multiple rapid swallows; applesauce 5 × 5 mL and 5 × 10 mL; and bread 5 × 2 × 2 cm and 5 × 4 × 4cm. HV rated difficulty of each swallow on a 5-point Likert scale. All HVs performed the protocol in supine position first and then in "semi-upright" (sitting 70 degrees in a bed) and "upright" (sitting in a chair) in a randomized order.
KEY RESULTS
Thirty-seven HVs, median age 27 years, 64% female completed this study. Median distal contractile integral (DCI) and integrated relaxation pressure 4 s (IRP4) of 5 mL liquid swallows significantly differed (all p < 0.01) between position performed. Large volume swallows resulted in higher DCI and lower IRP4. IRP4 results were significantly increased for 2 × 2 cm pieces of bread compared to 5 mL water swallows. DCI results were higher for 2 × 2 cm pieces of bread compared to 5 mL water swallows. Distal latency was shorter in more upright positions. Among this cohort of HV, perceived difficulty of bolus passage was more likely to occur with solid boluses.
CONCLUSIONS AND INFERENCES
The volume and consistency of a swallow and the position it is performed in, significantly alter HRM metrics. Interpretation of HRM studies should incorporate different normative values which are specific to the position and bolus type.
Topics: Humans; Female; Adult; Male; Deglutition; Esophagus; Manometry; Sitting Position; Water; Esophageal Motility Disorders
PubMed: 37036395
DOI: 10.1111/nmo.14593 -
Scientific Reports Jul 2020The arrangement and composition of habitats within landscapes and fine-scale habitat characteristics influence community structure and ecological processes. These...
The arrangement and composition of habitats within landscapes and fine-scale habitat characteristics influence community structure and ecological processes. These aspects can be altered by anthropogenic activities, thus influencing associated assemblages. Farming of macroalgae is a common practice in tropical settings and alters the natural composition of seascapes by introducing monoculture patches. The farmed macroalgae may also differ in palatability compared to naturally-occurring macroalgae, influencing herbivory. This study assessed how these farms may differ from natural macroalgal beds in terms of habitat heterogeneity, fish assemblages, and herbivory. We surveyed fish assemblages and deployed macroalgal assays within macroalgal beds, farms and at varying distances from these habitats near Mafia Island, Tanzania. Fish composition and herbivory differed between the habitats likely due to different macrophyte species richness, underlying hard substrate in natural macroalgal beds, and high abundance of browsers nearby the farms. Additionally, fish assemblage patterns and herbivory were not consistent across the seascapes and varied with distance from the focal habitats possibly due to the presence of other habitats. The results suggest alterations of seascapes by farming practices may have consequences on fish assemblages and the ecological functions performed, thus positioning of farms should be carefully considered in management and conservation plans.
Topics: Animals; Ecosystem; Fishes; Indian Ocean; Seaweed; Tanzania
PubMed: 32719358
DOI: 10.1038/s41598-020-68904-4 -
Bioelectromagnetics 2005This paper reviews experimental studies on the effects of radiofrequency (RF), extremely low frequency (ELF), and intermediate frequency (IF) electromagnetic fields on... (Review)
Review
This paper reviews experimental studies on the effects of radiofrequency (RF), extremely low frequency (ELF), and intermediate frequency (IF) electromagnetic fields on animal development. Numerous studies have shown that RF fields are teratogenic at exposure levels sufficiently high to cause significant increase of temperature. There is no consistent evidence of RF field effects at nonthermal exposure levels. Only a few studies have evaluated possible effects on postnatal development using sensitive endpoints, such as behavioral effects. ELF electric fields up to 150 kV/m have been evaluated in several mammalian species. The results are rather consistent and do not suggest adverse developmental effects. The results of studies on ELF magnetic fields suggest effects on bird embryo development, but not consistently in all studies. Results from experiments with other non-mammalian experimental models have also suggested subtle effects on developmental stability. In mammals, most studies have shown no effects of prenatal exposure to ELF or IF magnetic on gross external, visceral, or skeletal malformations. The only finding that shows some consistency is increase of minor skeleton alterations in several experiments. Taken as a whole, the results do not show robust adverse effects of ELF and IF fields on development. However, additional studies on the suggested subtle effects on developmental stability might increase our understanding of the sensitivity of biological organisms to weak low-frequency magnetic fields.
Topics: Aging; Animals; Behavior, Animal; Electromagnetic Fields; Female; Growth; Pregnancy; Prenatal Exposure Delayed Effects; Radiation Dosage
PubMed: 16037961
DOI: 10.1002/bem.20125 -
Developments in Biological... 1994Production of proteins of consistent quality in heterologous, genetically-engineered expression systems is dependent upon identifying the manufacturing process... (Review)
Review
Production of proteins of consistent quality in heterologous, genetically-engineered expression systems is dependent upon identifying the manufacturing process parameters which have an impact on product structure, function, or purity, validating acceptable ranges for these variables, and performing the manufacturing process as specified. One of the factors which may affect product consistency is genetic instability of the primary product sequence, as well as instability of genes which code for proteins responsible for post-translational modification of the product. Approaches have been developed for mammalian expression systems to assure that product quality is not changing through mechanisms of genetic instability. Sensitive protein analytical methods, particularly peptide mapping, are used to evaluate product structure directly, and are more sensitive in detecting genetic instability than is direct genetic analysis by nucleotide sequencing of the recombinant gene or mRNA. These methods are being employed to demonstrate that the manufacturing process consistently yields a product of defined structure from cells cultured through the range of cell ages used in the manufacturing process and well beyond the maximum cell age defined for the process. The combination of well designed validation studies which demonstrate consistent product quality as a function of cell age, and rigorous quality control of every product lot by sensitive protein analytical methods provide the necessary assurance that product structure is not being altered through mechanisms of mutation and selection.
Topics: Biotechnology; DNA, Recombinant; Fermentation; Gene Amplification; Humans; Molecular Structure; Mutation; Peptide Mapping; Protein Engineering; Quality Control; Recombinant Proteins; Tissue Plasminogen Activator
PubMed: 7883099
DOI: No ID Found -
Kidney International. Supplement Sep 1998Evidence suggests that a minimal luminal [K+] is required to elicit a full tubuloglomerular feedback (TGF) response, consistent with transmission of the TGF signal... (Review)
Review
Evidence suggests that a minimal luminal [K+] is required to elicit a full tubuloglomerular feedback (TGF) response, consistent with transmission of the TGF signal across the macula densa (MD) via the Na+-2Cl(-)-K+ cotransporter. Furthermore, it appears that luminal [K+] at the MD is close to the K+ affinity of the Na+-2Cl(-)-K+ cotransporter and changes in response to altering late proximal tubular flow rate (VLP), that is, a maneuver that induces a TGF response. These findings suggest that luminal [K+] (besides [Cl-]) could be rate limiting in TGF. In the thick ascending limb of Henle's loop (TALH), most of the luminal K+ is derived from recycling across the apical tubular membrane. Because changing VLP causes relatively greater alterations in the absolute Na+ and Cl- delivery to Henle's loop than in K+ load, the parallel changes of VLP and luminal [K+] at the MD, despite significant alteration in K+-dependent reabsorption of Na+ and Cl- via the Na+-2Cl(-)-K+ cotransporter, imply a transport-dependent adaptation of K+ recycling in TALH.
Topics: Animals; Feedback; Humans; Kidney Glomerulus; Kidney Tubules; Potassium; Signal Transduction
PubMed: 9736282
DOI: 10.1046/j.1523-1755.1998.06739.x -
The Mental Health Clinician Nov 2016Schizophrenia is a severe disorder affecting approximately 1% of the population. Historically, alterations of dopaminergic function were considered the primary cause of...
Schizophrenia is a severe disorder affecting approximately 1% of the population. Historically, alterations of dopaminergic function were considered the primary cause of schizophrenia. However, for many patients, drugs that alter dopaminergic function do not consistently lead to resolution of the symptoms of schizophrenia. Thus, there is an increased interest in pathophysiologic processes that result in altered neurodevelopment and plasticity associated with schizophrenia. Brain-derived neurotrophic factor (BDNF) is a neurotrophin involved in neurogenesis, synaptic plasticity, cognition, and neurotransmission. Genetic polymorphism, expression, and function of BDNF have been implicated in psychiatric diseases, including schizophrenia. This review discusses BDNF, its role in neurologic processes, and the evidence implicating BDNF in schizophrenia.
PubMed: 29955483
DOI: 10.9740/mhc.2016.11.285 -
Psychopharmacology Apr 2014Social factors influence drug abuse. Conversely, drugs of abuse alter social behavior. This is especially pertinent during post-weaning development, when there are... (Review)
Review
RATIONALE
Social factors influence drug abuse. Conversely, drugs of abuse alter social behavior. This is especially pertinent during post-weaning development, when there are profound changes in the social repertoire, and the sensitivity to the positive and negative effects of drugs of abuse is altered.
OBJECTIVES
This study aimed to provide an overview of our current understanding of the interaction between drugs of abuse and juvenile/adolescent social behavior.
METHODS
We first provide evidence that a characteristic form of juvenile and adolescent social behavior, i.e., social play behavior, has reinforcing properties and is affected by drugs of abuse. Next, social risk factors for drug use and addiction are described, including antisocial personality traits and early social insults. Last, we discuss research that investigates social influences on drug use, as well as the consequences of perinatal drug exposure on later social interactions.
RESULTS
Social play behavior is highly rewarding in laboratory animals, and it is affected by low doses of opioids, cannabinoids, ethanol, nicotine, and psychostimulants. In humans, antisocial personality traits, most prominently in the form of conduct disorder, are a prominent risk factor for drug addiction. Preclinical studies have consistently shown altered sensitivity to drugs as a result of social isolation during post-weaning development. The social environment of an individual has a profound, but complex, influence on drug use, and perinatal drug exposure markedly alters later social interactions.
CONCLUSIONS
The studies reviewed here provide a framework to understand the interaction between drugs of abuse and adolescent social interaction, at the preclinical and the clinical level.
Topics: Adolescent; Animals; Humans; Illicit Drugs; Social Behavior; Substance-Related Disorders
PubMed: 24553578
DOI: 10.1007/s00213-014-3471-z -
Biological Psychiatry Sep 2015For over a century, clinicians have consistently described the paradoxical co-existence in posttraumatic stress disorder (PTSD) of sensory intrusive hypermnesia and... (Review)
Review
For over a century, clinicians have consistently described the paradoxical co-existence in posttraumatic stress disorder (PTSD) of sensory intrusive hypermnesia and declarative amnesia for the same traumatic event. Although this amnesia is considered as a critical etiological factor of the development and/or persistence of PTSD, most current animal models in basic neuroscience have focused exclusively on the hypermnesia, i.e., the persistence of a strong fear memory, neglecting the qualitative alteration of fear memory. The latest is characterized by an underrepresentation of the trauma in the context-based declarative memory system in favor of its overrepresentation in a cue-based sensory/emotional memory system. Combining psychological and neurobiological data as well as theoretical hypotheses, this review supports the idea that contextual amnesia is at the core of PTSD and its persistence and that altered hippocampal-amygdalar interaction may contribute to such pathologic memory. In a first attempt to unveil the neurobiological alterations underlying PTSD-related hypermnesia/amnesia, we describe a recent animal model mimicking in mice some critical aspects of such abnormal fear memory. Finally, this line of argument emphasizes the pressing need for a systematic comparison between normal/adaptive versus abnormal/maladaptive fear memory to identify biomarkers of PTSD while distinguishing them from general stress-related, potentially adaptive, neurobiological alterations.
Topics: Animals; Disease Models, Animal; Fear; Humans; Memory Disorders; Mice; Stress Disorders, Post-Traumatic
PubMed: 26238378
DOI: 10.1016/j.biopsych.2015.06.017 -
Biological Psychiatry Jul 2006Transcriptome profiling using DNA microarrays are data-driven approaches with the potential to uncover unanticipated relationships between gene expression alterations... (Review)
Review
Transcriptome profiling using DNA microarrays are data-driven approaches with the potential to uncover unanticipated relationships between gene expression alterations and psychiatric disorders. Studies to date have yielded both convergent and divergent findings. Differences may be explained, at least in part, by the use of a variety of microarray platforms and analytical approaches. Consistent findings across studies suggest, however, that important relationships may exist between altered gene expression and genetic susceptibility to psychiatric disorders. For example, GAD67, RGS4, DTNBP1, NRG1, and GABRAB2 show expression alterations in the postmortem brain of subjects with schizophrenia, and these genes have been also implicated as putative, heritable schizophrenia susceptibility genes. Thus, we propose that for some genes, altered expression in the postmortem human brain may have a dual origin: polymorphisms in the candidate genes themselves or upstream genetic-environmental factors that converge to alter their expression level. We hypothesize that certain gene products, which function as "molecular hubs," commonly show altered expression in psychiatric disorders and confer genetic susceptibility for one or more diseases. Microarray gene expression studies are ideally suited to reveal these putative disease-associated molecular hubs and to identify promising candidates for genetic association studies.
Topics: DNA; Gene Expression Regulation; Genomics; Humans; Mental Disorders; Oligonucleotide Array Sequence Analysis; Psychiatry
PubMed: 16616896
DOI: 10.1016/j.biopsych.2006.02.003 -
Neuroscience and Biobehavioral Reviews Jun 2024Similar to addictive substances, addictive behaviours such as gambling and gaming are associated with maladaptive modulation of key brain areas and functional networks... (Review)
Review
Similar to addictive substances, addictive behaviours such as gambling and gaming are associated with maladaptive modulation of key brain areas and functional networks implicated in learning and memory. Therefore, this review sought to understand how different learning and memory processes relate to behavioural addictions and to unravel their underlying neural mechanisms. Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically searched four databases - PsycINFO, PubMed, Scopus, and Web of Science using the agreed-upon search string. Findings suggest altered executive function-dependent learning processes and enhanced habit learning in behavioural addiction. Whereas the relationship between working memory and behavioural addiction is influenced by addiction type, working memory aspect, and task nature. Additionally, long-term memory is incoherent in individuals with addictive behaviours. Consistently, neurophysiological evidence indicates alterations in brain areas and networks implicated in learning and memory processes in behavioural addictions. Overall, the present review argues that, like substance use disorders, alteration in learning and memory processes may underlie the development and maintenance of behavioural addictions.
PubMed: 38870547
DOI: 10.1016/j.neubiorev.2024.105747