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Current Opinion in Cell Biology Dec 2019The three germ layers - mesoderm, endoderm and ectoderm - constituting the cellular blueprint for the tissues and organs that will form during embryonic development, are... (Review)
Review
The three germ layers - mesoderm, endoderm and ectoderm - constituting the cellular blueprint for the tissues and organs that will form during embryonic development, are specified at gastrulation. Cells of mesodermal origin are the most abundant in the human body, representing a great variety of cell types, including the musculoskeletal system (bone, cartilage and muscle), cardiovascular system (heart, blood and blood vessels), as well as the connective tissues found throughout our bodies. A long-standing question pertains how this panoply of mesodermal cell types arises in a stereotypical fashion in time and space. This review discusses the events associated with mesoderm specification, highlighting the reconstruction of putative developmental trajectories facilitated by recent single-cell 'omic' data. We will also discuss the potential of emergent organoid systems to emulate and interrogate the dynamics of lineage specification at cellular resolution.
Topics: Animals; Cell Differentiation; Cell Lineage; Ectoderm; Embryonic Development; Endoderm; Gastrulation; Humans; Mesoderm
PubMed: 31476530
DOI: 10.1016/j.ceb.2019.07.012 -
Life (Basel, Switzerland) Mar 2022During space missions, astronauts are faced with a variety of challenges that are unique to spaceflight and that have been known to cause physiological changes in humans... (Review)
Review
During space missions, astronauts are faced with a variety of challenges that are unique to spaceflight and that have been known to cause physiological changes in humans over a period of time. Several of these changes occur at the microbiome level, a complex ensemble of microbial communities residing in various anatomic sites of the human body, with a pivotal role in regulating the health and behavior of the host. The microbiome is essential for day-to-day physiological activities, and alterations in microbiome composition and function have been linked to various human diseases. For these reasons, understanding the impact of spaceflight and space conditions on the microbiome of astronauts is important to assess significant health risks that can emerge during long-term missions and to develop countermeasures. Here, we review various conditions that are caused by long-term space exploration and discuss the role of the microbiome in promoting or ameliorating these conditions, as well as space-related factors that impact microbiome composition. The topics explored pertain to microgravity, radiation, immunity, bone health, cognitive function, gender differences and pharmacomicrobiomics. Connections are made between the trifecta of spaceflight, the host and the microbiome, and the significance of these interactions for successful long-term space missions.
PubMed: 35454986
DOI: 10.3390/life12040495 -
Journal of Cognitive Neuroscience Sep 2021The space around our body, the so-called peripersonal space, is where interactions with nearby objects may occur. "Defensive space" and "Reaching space", respectively,...
The space around our body, the so-called peripersonal space, is where interactions with nearby objects may occur. "Defensive space" and "Reaching space", respectively, refer to two opposite poles of interaction between our body and the external environment: protecting the body and performing a goal-directed action. Here, we hypothesized that mechanisms underlying these two action spaces are differentially modulated by the valence of visual stimuli, as stimuli with negative valence are more likely to activate protective actions whereas stimuli with positive valence may activate approaching actions. To test whether such distinction in cognitive/evaluative processing exists between Reaching and Defensive spaces, we measured behavioral responses as well as neural activations over sensorimotor cortex using EEG while participants performed several tasks designed to tap into mechanisms underlying either Defensive (e.g., respond to touch) or Reaching space (e.g., estimate whether object is within reaching distance). During each task, pictures of objects with either positive or negative valence were presented at different distances from the participants' body. We found that Defensive space was smaller for positively compared with negatively valenced visual stimuli. Furthermore, sensorimotor cortex activation (reflected in modulation of beta power) during tactile processing was enhanced when coupled with negatively rather than positively valenced visual stimuli regarding Defensive space. On the contrary, both the EEG and behavioral measures capturing the mechanisms underlying Reaching space did not reveal any modulation by valence. Thus, although valence encoding had differential effects on Reaching and Defensive spaces, the distance of the visual stimulus modulated behavioral measures as well as activity over sensorimotor cortex (reflected in modulations of mu power) in a similar way for both types of spaces. Our results are compatible with the idea that Reaching and Defensive spaces involve the same distance-dependent neural representations of sensory input, whereas task goals and stimulus valence (i.e., contextual information) are implemented at a later processing stage and exert an influence on motor output rather than sensory/space encoding.
Topics: Humans; Personal Space; Space Perception; Touch; Touch Perception
PubMed: 34424990
DOI: 10.1162/jocn_a_01749 -
Nutrients Nov 2022Astronauts exhibit several pathophysiological changes due to a variety of stressors related to the space environment, including microgravity, space radiation, isolation,... (Review)
Review
Astronauts exhibit several pathophysiological changes due to a variety of stressors related to the space environment, including microgravity, space radiation, isolation, and confinement. Space motion sickness, bone and muscle mass loss, cardiovascular deconditioning and neuro-ocular syndrome are some of the spaceflight-induced effects on human health. Optimal nutrition is of the utmost importance, and-in combination with other measures, such as physical activity and pharmacological treatment-has a key role in mitigating many of the above conditions, including bone and muscle mass loss. Since the beginning of human space exploration, space food has not fully covered astronauts' needs. They often suffer from menu fatigue and present unintentional weight loss, which leads to further alterations. The purpose of this review was to explore the role of nutrition in relation to the pathophysiological effects of spaceflight on the human body.
Topics: Humans; Space Flight; Weightlessness; Astronauts; Nutritional Status; Exercise
PubMed: 36432580
DOI: 10.3390/nu14224896 -
Advances in Skin & Wound Care Jul 2023To present the toe web space as an anatomically, physiologically, and pathologically unique part of the human body; characterize toe web infections and discuss why they... (Review)
Review
OBJECTIVE
To present the toe web space as an anatomically, physiologically, and pathologically unique part of the human body; characterize toe web infections and discuss why they occur; and highlight toe web psoriasis as an uncommon condition that providers should consider if toe web intertrigo does not respond to treatment.
DATA SOURCE
This review encompassed many years of clinical observation and photographs; medical textbooks; and a literature search of MEDLINE, PubMed, and Google Scholar.
STUDY SELECTION
Primary research keywords included intertrigo, toe web intertrigo, toe web infection, tinea pedis, microbiome, skin microbiome, toe web microbiome, ecology, psoriasis, psoriasis microbiome, intertriginous psoriasis, and Wood's lamp. More than 190 journal articles met the search criteria.
DATA EXTRACTION
The authors sought data relating to what makes for a healthy toe web space and what makes for disease. They extracted and collated relevant information to compare and contrast among sources.
DATA SYNTHESIS
After understanding the normal toe web space and the microorganisms that normally reside there, the authors investigated why infections occur, how they should be treated, what complications may result, and what other diseases occur in the toe web area.
CONCLUSIONS
This review of toe web infection illustrates the effect of the microbiome and reports a rare form of psoriasis that is usually misdiagnosed as athlete's foot. The toe web space is a unique part of the human body that can be affected by a variety of both common and unusual conditions.
Topics: Humans; Tinea Pedis; Foot; Toes; Psoriasis; Intertrigo
PubMed: 37224470
DOI: 10.1097/01.ASW.0000933728.56221.82 -
Materials (Basel, Switzerland) Nov 2021Comfort can be considered as subjective feeling, which could be affected by the external ambient, by the physical activity, and by clothing. Considering the human body...
Comfort can be considered as subjective feeling, which could be affected by the external ambient, by the physical activity, and by clothing. Considering the human body heat transfer system, it mainly depends on various parameters including clothing materials, external and internal environment, etc. The purpose of the current paper is to study and establish a quantitative relationship between one of the clothing parameters, ease allowance (air gap values) and the heat transfer through the human body to clothing materials and then to the environment. The study considered clothing which is integrated with the 3D ease allowance from the anthropometric and morphological data. Such incorporating of the clothing's 3D ease control was essential to properly manage the air space between the body and the proposed clothing thermal regulation model. In the context of thermal comfort, a clothing system consisting of the human body, an ease allowance under clothing, a layer of textile materials, and a peripheral layer adjacent to the textile material was used. For the complete system, the heat transfer from the skin to the environment, which is influenced by thermoregulation of the human body, air gap, tissue, and environmental conditions were also considered. To model and predict the heat transfer between the human body and the temperature of skin and clothes, a 3D adaptive garment which could be adjusted with ease allowance was used. In the paper, a thermoregulatory model was developed and proposed to predict the temperature and heat within clothing material, skin, and air space. Based on the result, in general the main difference in the temperature of clothing and skin from segment to segment is due to the uneven distribution of air layers under the clothing.
PubMed: 34772206
DOI: 10.3390/ma14216675 -
The Japanese Dental Science Review Feb 2016Nitric oxide (NO) is a free radical which is produced from a wide variety of cells and tissues in the human body. NO is involved in the regulation of many physiological... (Review)
Review
Nitric oxide (NO) is a free radical which is produced from a wide variety of cells and tissues in the human body. NO is involved in the regulation of many physiological processes, such as vascular relaxation, neurotransmission, immune regulation, and cell death. NO is generated by nitric oxide synthase (NOS), which has three identified isoforms: neuronal type NOS (nNOS), endothelial type NOS (eNOS), and inducible type NOS (iNOS). Different isoforms are expressed depending on the organs, tissues, and cells, and investigation of the types and functions of enzymes expressed in various tissues is underway. The oral cavity is a space in which marked changes have been detected in NO levels, and each tissue is constantly influenced by NO. NO is a component of saliva and is produced by oral bacteria in the oral cavity and released by NOS expressed in oral mucosa. NOS isoforms expressed under normal conditions differ among the oral organs. In addition, the overexpression of NOS was involved in carcinogenesis and tumor growth progression. This review summarized the expression of NOS and functions of NO in oral cavity organs, and their roles in diseases and the influences of treatments.
PubMed: 28408951
DOI: 10.1016/j.jdsr.2015.08.001 -
Periodontology 2000 Feb 2020In humans, the composition of microbial communities differs among body sites and between habitats within a single site. Patterns of variation in the distribution of... (Review)
Review
In humans, the composition of microbial communities differs among body sites and between habitats within a single site. Patterns of variation in the distribution of organisms across time and space are referred to as "biogeography." The human oral cavity is a critical observatory for exploring microbial biogeography because it is spatially structured, easily accessible, and its microbiota has been linked to the promotion of both health and disease. The biogeographic features of microbial communities residing in spatially distinct, but ecologically similar, environments on the human body, including the subgingival crevice, have not yet been adequately explored. The purpose of this paper is twofold. First, we seek to provide the dental community with a primer on biogeographic theory, highlighting its relevance to the study of the human oral cavity. We summarize what is known about the biogeographic variation of dental caries and periodontitis and postulate that disease occurrence reflects spatial patterning in the composition and structure of oral microbial communities. Second, we present a number of methods that investigators can use to test specific hypotheses using biogeographic theory. To anchor our discussion, we apply each method to a case study and examine the spatial variation of the human subgingival microbiota in 2 individuals. Our case study suggests that the composition of subgingival communities may conform to an anterior-to-posterior gradient within the oral cavity. The gradient appears to be structured by both deterministic and nondeterministic processes, although additional work is needed to confirm these findings. A better understanding of biogeographic patterns and processes will lead to improved efficacy of dental interventions targeting the oral microbiota.
Topics: Dental Caries; Humans; Microbiota; Mouth; Periodontal Diseases; Periodontitis
PubMed: 31850642
DOI: 10.1111/prd.12268 -
Mikrochimica Acta Sep 2022Health problems have been widely concerned by all mankind. Real-time monitoring of disease-related biomarkers can feedback the physiological status of human body in... (Review)
Review
Health problems have been widely concerned by all mankind. Real-time monitoring of disease-related biomarkers can feedback the physiological status of human body in time, which is very helpful to the diseases management of healthcare. However, conventional non-flexible/rigid biochemical sensors possess low fit and comfort with the human body, hence hindering the accurate and comfortable long-time health monitoring. Flexible and stretchable materials make it possible for sensors to be continuously attached to the human body with good fit, and more precise and higher quality results can be obtained. Thus, tremendous attention has been paid to flexible biochemical sensors in point-of-care (POC) for real-time monitoring the entire disease process. Here, recent progress on flexible biochemical sensors for management of various diseases, focusing on chronic and communicable diseases, is reviewed, and the detection principle and performance of these flexible biochemical sensors are discussed. Finally, some directions and challenges are proposed for further development of flexible biochemical sensors.
Topics: Humans; Point-of-Care Systems; Wearable Electronic Devices
PubMed: 36094594
DOI: 10.1007/s00604-022-05469-1