The Roles of Sodium Transport and Anion Permeability in Generating Transepithelial Potential Differences in Larval Salamanders

THOMAS H. DIETZ; LEONARD B. KIRSCHNER; DAVID PORTER

doi:10.1242/jeb.46.1.85

The Roles of Sodium Transport and Anion Permeability in Generating Transepithelial Potential Differences in Larval Salamanders

Journal of Experimental Biology ◽

10.1242/jeb.46.1.85 ◽

1967 ◽

Vol 46 (1) ◽

pp. 85-96

Author(s):

THOMAS H. DIETZ ◽

LEONARD B. KIRSCHNER ◽

DAVID PORTER

Keyword(s):

Body Surface ◽

Pond Water ◽

The Body ◽

Ammonium Ion ◽

Salt Loading ◽

Transepithelial Potential ◽

Wide Range ◽

Independent Mechanism ◽

Salt Depletion ◽

Na Uptake

1. Larval salamanders in pond water actively transport both Na+ and Cl- inwards. The two fluxes can occur independently, indicating that they are not linked obligatorily through a single mechanism. Ammonia is excreted extrarenally at rates comparable with active Na+ influx. 2. A potential difference exists across the body surface of larval salamanders under these conditions. Over the range 0.1-10 mM the transepithelial potential (TEP) varies approximately logarithmically with [NaCl]. Only Na+ and Li+ salts generate such a TEP, while K+, Rb+, Ca2+, Mg2+, and NH4+ salts have little effect. Azide and dinitrophenol abolish the TEP, while strophanthin has no effect. When active Na+ uptake is enhanced by salt-depletion, higher TEPs are generated. Conversely, animals with Na+ transport depressed by salt-loading show significantly smaller TEPs. 3. The magnitude of the TEP is uneffected by replacing NaCl with Na2SO4. Permeability of the body surface to SO42- is very low, and the similarity in electrical behaviour of the two anions suggests that Cl- penetration by diffusion is also small. This surmise is supported by two observations: (1) KCl generates no TEP over a wide range of concentrations; and (2) cupric ion has no effect on the TEP developed in dilute NaCl solution. 4. It is suggested that the TEP in salamanders is generated by active inward transport of Na+, but that in dilute solutions electrostatic neutrality is maintained by a cation-exchange system involving ammonium ion. Uptake of Cl- under these conditions appears to occur by an independent mechanism and is non-electrogenic.

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Development and Validation of a New Scoring Tool to Evaluate the Clinical Evolution of Adult Patients with Nonsegmental Vitiligo

Dermatology ◽

10.1159/000511890 ◽

2021 ◽

pp. 1-9

Author(s):

María Luisa Peralta-Pedrero ◽

Denisse Herrera-Bringas ◽

Karla Samantha Torres-González ◽

Martha Alejandra Morales-Sánchez ◽

Fermín Jurado Santa-Cruz ◽

...

Keyword(s):

Body Surface ◽

Task Force ◽

Intraclass Correlation ◽

The Body ◽

Response To Treatment ◽

Similar Response ◽

Clinical Evolution ◽

Wide Range ◽

Patient Reported ◽

Extreme Groups

Background: Vitiligo has an unpredictable course and a variable response to treatment. Furthermore, the improvement of some vitiligo lesions cannot be considered a guarantee of a similar response to the other lesions. Instruments for patient-reported outcome measures (PROM) can be an alternative to measure complex constructions such as clinical evolution. Objective: The aim of this study was to validate a PROM that allows to measure the clinical evolution of patients with nonsegmental vitiligo in a simple but standardized way that serves to gather information for a better understanding of the disease. Methods: The instrument was created through expert consensus and patient participation. For the validation study, a prospective cohort design was performed. The body surface area affected was measured with the Vitiligo Extension Score (VES), the extension, the stage, and the spread by the evaluation of the Vitiligo European Task Force assessment (VETFa). Reliability was determined with test-retest, construct validity through hypothesis testing, discriminative capacity with extreme groups, and response capacity by comparing initial and final measurements. Results: Eighteen semi-structured interviews and 7 cognitive interviews were conducted, and 4 dermatologists were consulted. The instrument Clinical Evolution-Vitiligo (CV-6) was answered by 119 patients with a minimum of primary schooling. A wide range was observed in the affected body surface; incident and prevalent cases were included. The average time to answer the CV-6 was 3.08 ± 0.58 min. In the test-retest (n = 53), an intraclass correlation coefficient was obtained: 0.896 (95% CI 0.82–0.94; p < 0.001). In extreme groups, the mean score was 2 (2–3) and 5 (4–6); p < 0.001. The initial CV-6 score was different from the final one and the change was verified with VES and VETFa (p < 0.05, n = 92). Conclusions: The CV-6 instrument allows patient collaboration, it is simple and brief, and it makes it easier for the doctor to focus attention on injuries that present changes at the time of medical consultation.

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Bi-parental mucus provisioning in the scale-eating cichlid Perissodus microlepis (Cichlidae)

Biological Journal of the Linnean Society ◽

10.1093/biolinnean/blz124 ◽

2019 ◽

Author(s):

Shun Satoh ◽

Satoshi Awata ◽

Hirokazu Tanaka ◽

Lyndon A Jordan ◽

Umi Kakuda ◽

...

Keyword(s):

Parental Care ◽

Body Surface ◽

Direct Contact ◽

Lake Tanganyika ◽

Stomach Contents ◽

The Body ◽

Field Observations ◽

Teleost Fishes ◽

Wide Range ◽

Provisioning Behaviour

Abstract Although parental care is known to occur in a wide range of teleost fishes, postnatal provisioning of nutrition has been documented rarely. Here, we describe a novel example of bi-parental care in a teleost, i.e. mucus-provisioning behaviour in the scale-eating cichlid Perissodus microlepis endemic to Lake Tanganyika. Field observations revealed that young guarded by their parents frequently glanced towards the body surface of both parents. Furthermore, analyses of stomach contents of the young found the presence of ingested mucus, confirming that the young feed on the mucus secretions of their parents. The frequency of glancing behaviour increased with size of the young up to ~13 mm in standard length, but then declined with further growth. Additionally, the frequency of glancing of young towards their parents was higher when the frequency of foraging on plankton was lower. Underwater cage experiments revealed a higher rate of growth in the young kept in direct contact with their parents than in those not allowed direct contact. We conclude that glancing behaviour in young P. microlepis is a form of direct parental nourishment that confers growth benefits to the young when food abundance is low.

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The nonlinear problem of a gliding body with gravity

Journal of Fluid Mechanics ◽

10.1017/jfm.2013.256 ◽

2013 ◽

Vol 727 ◽

pp. 132-160 ◽

Cited By ~ 6

Author(s):

Y. A. Semenov ◽

G. X. Wu

Keyword(s):

Free Surface ◽

Body Surface ◽

Breaking Waves ◽

The Body ◽

Surface Shape ◽

Parameter Plane ◽

Hodograph Method ◽

Wide Range ◽

Free Surface Shape ◽

Analytical Expressions

AbstractAnalysis based on the velocity potential free flow theory with the fully nonlinear boundary condition is made for the steady flow generated by a body gliding along a free surface. Employing the integral hodograph method, we derive analytical expressions for the complex velocity and for the derivative of the complex potential with the coordinate of a parameter plane. The boundary value problem is transformed into a system of two integro-differential equations for the velocity modulus on the free surface and for the slope of the wetted body surface in the parameter plane. The same slope and curvature of the free surface and the body surface at the intersection are adopted to determine the separation points of the flow and from the body. Numerical results are provided for a gliding flat plate and a circular cylinder. The pressure distribution along the body and the free surface shape are presented for a wide range of Froude numbers, within the limit for which the solution corresponding to non-breaking waves downstream can be obtained.

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Sodium Influx and Loss in Freshwater and Brackish-Water Populations of the Amphipod Gammarus Duebeni Lilljeborg

Journal of Experimental Biology ◽

10.1242/jeb.54.1.255 ◽

1971 ◽

Vol 54 (1) ◽

pp. 255-268

Author(s):

D. W. SUTCLIFFE

Keyword(s):

Body Surface ◽

Brackish Water ◽

Sea Water ◽

Sodium Concentration ◽

The Body ◽

Experimental Population ◽

Sodium Ions ◽

Sodium Influx ◽

Wide Range ◽

Freshwater Habitats

1. Sodium influx was examined in Gammarus duebeni from freshwater habitats on the Kintyre and Stranraer peninsulas in western Britain, and from a brackish-water habitat in Ireland. The affinity for sodium ions in the uptake mechanism at the body surface was similar in animals from the three localities. 2. Compared with the parent population from Kintyre, an experimental population established for 2 years in water with a lower sodium concentration showed an increased affinity for sodium. 3. Sodium losses in the urine of animals from the above localities were negligible at external salinities below about 2% sea water. In contrast, urinary sodium losses in animals from a brackish-water population in Britain were higher at salinities ranging from 40% sea water to well below 2% sea water. 4. The affinity for sodium ions in uptake mechanisms at the body surface and in the antennary glands of G. duebeni from a wide range of habitats shows a market correlation with the sodium concentration of the habitat. The permeability of the body surface to outward movement of sodium is similar in G. duebeni from brackishwater and freshwater habitats. 5. It is suggested that most of the observed physiological differences between populations of G. duebeni are phenotypic in origin. The status of the freshwater ‘race’ in Ireland is briefly discussed.

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Sodium transport in the freshwater mussel, Carunculina texasensis (Lea)

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1978.235.1.r35 ◽

1978 ◽

Vol 235 (1) ◽

pp. R35-R40 ◽

Cited By ~ 1

Author(s):

T. H. Dietz

Keyword(s):

Steady State ◽

Sodium Transport ◽

Freshwater Mussel ◽

Ammonium Ion ◽

Bathing Solution ◽

Na Transport ◽

Sodium Influx ◽

Salt Depletion ◽

Freshwater Bivalves ◽

Na Uptake

Freshwater bivalves maintain a Na steady state in artificial pondwater: JiNa = 1.2 +/- 0.1 mumol/g dry tissue per h. Na uptake is Cl independent. The affinity (KS) of the Na transport system is 0.15-0.23 mmol Na/1. Sodium influx is coupled to H and/or NH4 exchange. Salt depletion stimulates JiNa 300% relative to nondepleted animals with no change in Ks. Injected ammonium ion stimulates JiNa. Sodium transport is inhibited 84% by 0.5 mM amiloride but is not affected by 4 mM NH4 or 1 mM furosemide in the bathing solution or injection of acetazolamide (0.26 mumol/ml blood).

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The Role of Computer Modeling in Electrocardiography

Methods of Information in Medicine ◽

10.1055/s-0038-1634809 ◽

1990 ◽

Vol 29 (04) ◽

pp. 282-288 ◽

Cited By ~ 2

Author(s):

A. van Oosterom

Keyword(s):

Electrical Activity ◽

Computer Modeling ◽

Body Surface ◽

Electrical Current ◽

The Body ◽

Volume Conductor ◽

Current Generator ◽

Cardiac Electrical Activity ◽

Source Models

AbstractThis paper introduces some levels at which the computer has been incorporated in the research into the basis of electrocardiography. The emphasis lies on the modeling of the heart as an electrical current generator and of the properties of the body as a volume conductor, both playing a major role in the shaping of the electrocardiographic waveforms recorded at the body surface. It is claimed that the Forward-Problem of electrocardiography is no longer a problem. Several source models of cardiac electrical activity are considered, one of which can be directly interpreted in terms of the underlying electrophysiology (the depolarization sequence of the ventricles). The importance of using tailored rather than textbook geometry in inverse procedures is stressed.

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The use of Body Surface Index as a Better Clinical Health indicators Compare to Body Mass Index and Body Surface Area for Clinical Application

International Journal of Scientific Research in Science Engineering and Technology ◽

10.32628/ijsrset2184117 ◽

2018 ◽

pp. 131-136

Author(s):

Shirazu I. ◽

Theophilus. A. Sackey ◽

Elvis K. Tiburu ◽

Mensah Y. B. ◽

Forson A.

Keyword(s):

Surface Area ◽

Body Surface Area ◽

Clinical Application ◽

Body Surface ◽

Body Height ◽

Health Indicators ◽

The Body ◽

Body Parameters ◽

The Relationship ◽

Individual Body

The relationship between body height and body weight has been described by using various terms. Notable among them is the body mass index, body surface area, body shape index and body surface index. In clinical setting the first descriptive parameter is the BMI scale, which provides information about whether an individual body weight is proportionate to the body height. Since the development of BMI, two other body parameters have been developed in an attempt to determine the relationship between body height and weight. These are the body surface area (BSA) and body surface index (BSI). Generally, these body parameters are described as clinical health indicators that described how healthy an individual body response to the other internal organs. The aim of the study is to discuss the use of BSI as a better clinical health indicator for preclinical assessment of body-organ/tissue relationship. Hence organ health condition as against other body composition. In addition the study is `also to determine the best body parameter the best predict other parameters for clinical application. The model parameters are presented as; modeled height and weight; modelled BSI and BSA, BSI and BMI and modeled BSA and BMI. The models are presented as clinical application software for comfortable working process and designed as GUI and CAD for use in clinical application.

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Creating the Wind

Latin American and Latinx Visual Culture ◽

10.1525/lavc.2020.2.4.14 ◽

2020 ◽

Vol 2 (4) ◽

pp. 14-31

Author(s):

Élodie Dupey García

Keyword(s):

Indigenous Communities ◽

The Body ◽

Historical Sources ◽

Natural Behavior ◽

Sensory Experiences ◽

Identity And Agency ◽

Wide Range ◽

Late Postclassic ◽

Comparative Examination ◽

Meteorological Phenomenon

This article explores how the Nahua of late Postclassic Mesoamerica (1200–1521 CE) created living and material embodiments of their wind god constructed on the basis of sensory experiences that shaped their conception of this divinized meteorological phenomenon. In this process, they employed chromatic and design devices, based on a wide range of natural elements, to add several layers of meaning to the human, painted, and sculpted supports dressed in the god’s insignia. Through a comparative examination of pre-Columbian visual production—especially codices and sculptures—historical sources mainly written in Nahuatl during the viceregal period, and ethnographic data on indigenous communities in modern Mexico, my analysis targets the body paint and shell jewelry of the anthropomorphic “images” of the wind god, along with the Feathered Serpent and the monkey-inspired embodiments of the deity. This study identifies the centrality of other human senses beyond sight in the conception of the wind god and the making of its earthly manifestations. Constructing these deity “images” was tantamount to creating the wind because they were intended to be visual replicas of the wind’s natural behavior. At the same time, they referred to the identity and agency of the wind god in myths and rituals.

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