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At least 19 recordsLinked to original sources
PubMed2026

DeepLabCut-based automated system reveals diverse temperature tolerance among medaka strains and related Oryzias species.

Temperature is a critical environmental factor influencing the physiology and behavior of ectothermic animals, yet conventional methods for evaluating thermal tolerance in fish rely on subjective manual observation of loss of equilibrium (LOE), limiting experimental throughput and introducing observer bias. Here, we developed an automated temperature tolerance evaluation system integrating DeepLabCut-based pose estimation with custom image processing algorithms to objectively quantify the timing of LOE during thermal stress tests. Our system incorporated region partitioning and color transformation preprocessing to improve keypoint detection accuracy, followed by a classification model combining ResNet34-based frame features with keypoint coordinates to objectively determine the timing of LOE without manual observation. Validation against manual annotation showed that the automated system achieved an accuracy comparable to the natural variability between trained investigators, and outperformed naive human observers, supporting its validity as an objective and reproducible alternative to manual scoring. Using this system, we characterized cold and heat tolerance across six medaka strains (Oryzias latipes: d-rR/TOKYO, HB11A, OK-Cab, HO5 and HdrR-II1; O. sakaizumii: HNI-II). Cold and heat tolerance assessment revealed inter-strain variation, with HdrR-II1 among the most cold- and heat-tolerant strains and HNI-II the least tolerant of both cold and heat stress. We further evaluated cold tolerance in medaka-related species (O. sinensis, O. cabaranensis, O. curvinotus, O. luzonensis, O. celebensis, and O. javanicus) and zebrafish (Danio rerio), revealing substantial interspecific variation that broadly corresponded with latitudinal distribution. O. latipes, distributed at the highest latitudes among the tested species, exhibited the greatest cold tolerance, whereas O. celebensis, O. javanicus, and other tropical or low-latitude species showed comparatively low cold tolerance. Our automated system provides a robust, high-throughput platform for thermal tolerance evaluation and, combined with the genetic and genomic resources available in medaka, establishes a foundation for elucidating the molecular mechanisms underlying temperature adaptation in fish.

Animals↗
PubMed1977

Equilibrial disturbances caused by hearing aids in hard of hearing children.

To 22 hard-of-hearing school pupils a 2 sec. tone pip of 1500 Hz was presented at 120 to 130 dB SPL's (equals 113-123 dB ISO) to both (=44) ears. In 32 of the ears (?) the sound stimulus elicited an ENG change and thus a possible disturbance of equilibrium, 2 cases of type A, 3-10 sec. nystagmus; I case of type B, with continuing nystagmus; 3 cases of type C, with strengthening nystagmus; and I case of type D, with direction-changing nystagmus, were found. We conclude that, in perceptive hearing defects, the maximum output of hearing aids should be limited to 120 dB, not only because of the effect on hearing thresholds. but also on the equilibrial sense. Again we recommend that hearing aids should not be used in those surroundings where loss of equilibrium is dangerous.

Adolescent↗
PubMed1979

The placing reaction in the standing cat: a model for the study of posture and movement.

By measuring the forces applied by each limb supporting the weight of the standing quadruped (cat), before and during elicitation of the placing reaction, it was possible to examine quantitatively and qualitatively the postural events which preceded and accompanied forelimb displacement. The findings are summarized as follows: 1. Postural adjustment consists of a shift from quadrupedal stance to a tripodal stance to permit withdrawal of weight from one forelimb without loss of equilibrium. The animal's weight is not equally distributed between the three supporting limbs but the majority of the weight is supported by the diagonally opposing limb pair. 2. During the isometric phase of the placing reaction, the animal's projected center of gravity moves contralaterally, across the diagonal line between the contralateral forepaw and the ipsilateral hindpaw, and comes to rest within the triangular zone outlined by the three supporting limbs. 3. The diagonal supporting stance is a maneuver of an anticipatory nature which precedes and accompanies the placing reaction. 4. The force changes exhibited by each limb to bring the animal to the stereotyped diagonal supporting stance illustrated that the way to achieve this is consistent within a given animal, but differs from one animal to another. The pattern in the same animal is generally symmetrical when lifting the right or left forepaw. 5. The data from the cat are compared to observations in other quadrupeds and man.

Animals↗
PubMed1978

[Ultrastructure study of the preneoplastic colon (carcinogenesis with 1,2-dimethylhydrazine)].

100 Wistar rats, belonging to a series of 500 animals, were treated with increasing doses and for increasing periods of time with 1,2-dimethylhydrazine. A previous study has shown that tumors begin to appear only after the 19th week. Before this period there are abnormalities of mucin secretion (by the 2nd week), and then there are dysplasic lesions (after the 4th week). The ultrastructure study, done before the 19th week ("pretumor" phase) confirms some previous observations (increase in the zone of mitosis, secretory changes, mutation producing effects). These features are reminiscent of the histochemical characteristics of the human foetal colon. They show an epitheliomesenchymatous disorganisation unrelated to inflammation. There are abnormally early changes in the vasculature, there is loss of the (epithelial) coat, there is dissociation of the basal membrane and abnormal connections between it and the epithelial cells, collagen and fibroblasts; all this represents a disorganisation of the regeneration system of the colon mucosa. This loss of equilibrium between the parenchyma and the mesenchyma may represent a factor favoring excessive and disorganised growth of the mucosa.

Adenocarcinoma↗
PubMed1979

The addictions as pathological mourning: an attempt at restitution of early losses.

Drug abuse is an attempt to resolve through the use of chemicals the psychic disequilibrium caused by intrapersonal (narcissistic) losses. The chemical equilibrium creates a false sense of quiet which retards the completion of the process of mourning for these losses. Due to the unconscious need to express these losses, addicts pick up clothing styles, behavior patterns, and grooming habits from the Judeo-Christian mourning and black ghetto rituals. In order to successfully give up the drug, the addict must resolve his grief by completing the stages of mourning in the process of group therapy.

Grief↗
PubMed1978

Neutrality or negligence: interpret or act?

The uniqueness of the psychotherapeutic relationship requires the therapists to maintain a careful equilibrium between objectivity at the price of empathy and closeness at the expense of the necessary perspective. Crises in the course of long-term psychotherapy brings about a sudden, unexpected loss of such equilibrium. Uithout sufficient understanding of the crisis within the context of the therapeutic strategy and goals, the therapist might easily over- or underreact, to the detriment of the treatment. In this paper we suggest careful scrutiny and guidelines for dealing with those situations.

Adult↗
PubMed1978

Indirect estimates of mutation rates in tribal Amerindians.

Three different formulations have been used to estimate the average rate/locus/generation with which mutation results in electrophoretically detectable variants of 28 proteins in 12 tribal Amerindian populations. All methods are indirect--i.e., they assume a reasonable approximation to equilibrium between mutation and loss of mutants from the population--and are based on the further assumption that the biochemical traits under consideration are essentially neutral in their phenotypic effects. Despite the fact that the methods draw on somewhat different aspects of the available data, there is satisfactory agreement between them, the average of the three estimates being 1.6 X 10(-5)/locus/generation. This average does not encompass mutation that does not result in a change in electrophoretic mobility or that results in loss of enzyme activity. It is noteworthy that this estimate is in satisfactory agreement with a recent estimate by Neel and Thompson [Neel, J. V. & Thompson, E. A. (1978) Proc. Natl. Acad. Sci. USA 75, 1904--1908] of the mutation pressure necessary to maintain the number of "private" genetic polymorphisms being encountered in Amerindian tribes, if selection is not a factor.

Genetic Variation↗
PubMed1979

B6.C-H-2bm12. A new H-2 mutation in the I region in the mouse.

The B6.C-H-2bm12 mutant is described and evidence is presented for the mutational site occurring in the IA subregion. The mutant is of the gain and loss type as bm12 in equilibrium or formed from C57BL/6 grafts are rejected in 14-16 d. Mapping studies by the gene-complementation method using H-2 recombinant strains place the mutation in the K or IA regions of the H-2 complex and furthermore, the use of this test and the use of other H-2 mutants indicate that H-2Kb is not the site of the mutation, making the IA region the most likely site. Serological analysis with a battery of H-2b, Iab, and other Ia sera, both by cytotoxicity, rosetting, and also by absorption analysis, indicated no alteration in H-2 specificities, particularly in H-2.K33. By contrast, all of the Iab specificities coded for by the IA subregion (Ia.3, 8, 9, 15, and possibly 20) are extensively altered and are either absent or greatly reduced in amount indicating an extensive alteration in the Ia-bearing molecule. The bm12 mutant strongly stimulates the parental C57BL/6 strain in an mixed lymphocyte reaction (MLR), and the reciprocal also occurs, the degree of stimulation being similar to that obtained with K + IA differences originating in another H-2 haplotype and points to the mutation effecting the Lad-1 locus. The presence of an extensive histocompatibility change, a marked alteration in the serologically detected Ia specificities, and a strong MLR, all produced by the one mutation, provides strong evidence for the identity of the Ia-1, Lad-1, and H-2(IA) loci in the IA subregion. The bm12 mutant should be of value in determining the relationship of Ia specificities, Ir genes, and other phenomena effected by the I region.

Animals↗
PubMed1979

The effects of sibling death on the surviving child: a family perspective.

The death of a child invariably affects the family, who in effect become survivors. Adaptations are made in order to secure a new family equilibrium attendant upon such a loss. Surviving siblings not infrequently become the focus of maneuvers unconsciously designed to alleviate guilt and control fate through silence and efforts to maintain silence, through substitution for the lost child, and through endowing the survivor-child with qualities of the deceased. Three types of clinically identifiable types of survivor-children are described. Families that emphasize silence and focus on guilt, families in which the child becomes incomparably precious, and families in which substitution and replacement provide the major theme lead respectively to the "haunted," "bound," and "resurrected" child. These children share many features, as do their families, but there appears to be a connection between the family defensive maneuver and the specific consequences for a child of the bereaved family.

Adaptation, Psychological↗
PubMed2024

Assessing nanobody interaction with SARS-CoV-2 Nsp9.

The interaction between SARS-CoV-2 non-structural protein Nsp9 and the nanobody 2NSP90 was investigated by NMR spectroscopy using the paramagnetic perturbation methodology PENELOP (Paramagnetic Equilibrium vs Nonequilibrium magnetization Enhancement or LOss Perturbation). The Nsp9 monomer is an essential component of the replication and transcription complex (RTC) that reproduces the viral gRNA for subsequent propagation. Therefore preventing Nsp9 recruitment in RTC would represent an efficient antiviral strategy that could be applied to different coronaviruses, given the Nsp9 relative invariance. The NMR results were consistent with a previous characterization suggesting a 4:4 Nsp9-to-nanobody stoichiometry with the occurrence of two epitope pairs on each of the Nsp9 units that establish the inter-dimer contacts of Nsp9 tetramer. The oligomerization state of Nsp9 was also analyzed by molecular dynamics simulations and both dimers and tetramers resulted plausible. A different distribution of the mapped epitopes on the tetramer surface with respect to the former 4:4 complex could also be possible, as well as different stoichiometries of the Nsp9-nanobody assemblies such as the 2:2 stoichiometry suggested by the recent crystal structure of the Nsp9 complex with 2NSP23 (PDB ID: 8dqu), a nanobody exhibiting essentially the same affinity as 2NSP90. The experimental NMR evidence, however, ruled out the occurrence in liquid state of the relevant Nsp9 conformational change observed in the same crystal structure.

Viral Nonstructural Proteins↗
PubMed1976

Thyroxine-protein interactions. Interaction of thyroxine and triiodothyronine with human thyroxine-binding globulin.

The effect of temperature on the binding of thyroxine and triiodothyronine to thyroxine-binding globulin has been studied by equilibrium dialysis. Inclusion of ovalbumin in the dialysis mixture stabilized thyroxine-binding globulin against losses in binding activity which had been found to occur during equilibrium dialysis. Ovalbumin by itself bound the thyroid hormones very weakly and its binding could be neglected when analyzing the experimental results. At pH 7.4 and 37 degrees in 0.06 M potassium phosphate/0.7 mM EDTA buffer, thyroxine was bound to thyroxine-binding globulin at a single binding site with apparent association constants: at 5 degrees, K = 4.73 +/- 0.38 X 10(10) M-1; at 25 degrees, K = 1.55 +/- 0.17 X 10(10) M-1; and at 37 degrees, K = 9.08 +/- 0.62 X 10(9) M-1. Scatchard plots of the binding data for triiodothyronine indicated that the binding of this compound to thyroxine-binding globulin was more complex than that found for thyroxine. The data for triiodothyronine binding could be fitted by asuming the existence of two different classes of binding sites. At 5 degrees and pH 7.4 nonlinear regression analysis of the data yielded the values n1 = 1.04 +/- 0.10, K1 = 3.35 +/- 0.63 X 10(9) M-1 and n2 = 1.40 +/- 0.08, K2 = 0.69 +/- 0.20 X 10(8) M-1. At 25 degrees, the values for the binding constants were n1 = 1.04 +/- 0.38, K1 = 6.5 +/- 2.8 X 10(8) M-1 and n2 = 0.77 +/- 0.22, K2 = 0.43 +/- 0.62 X 10(8) M-1. At 37 degrees where less curvature was observed, the estimated binding constants were n1 = 1.02 +/- 0.06, K1 = 4.32 +/- 0.59 X 10(8) M-1 and n2K2 = 0.056 +/- 0.012 X 10(8) M-1. When n1 was fixed at 1, the resulting values obtained for the other three binding constants were at 25 degrees, K1 = 6.12 +/- 0.35 X 10(8) M-1, n2 = 0.72 +/- 0.18, K2 = 0.73 +/- 0.36 X 10(8) M-1; and at 37 degrees K1 = 3.80 +/- 0.22 X 10(8) M-1, n2 = 0.44 +/- 0.22, and K2 = 0.43 +/- 0.38 X 10(8) M-1. The thermodynamic values for thyroxine binding to thyroxine-binding globulin at 37 degrees and pH 7.4 were deltaG0 = -14.1 kcal/mole, deltaH0 = -8.96 kcal/mole, and deltaS0 = +16.7 cal degree-1 mole-1. For triiodothyronine at 37 degrees, the thermodynamic values for binding at the primary binding site were deltaG0 = -12.3 kcal/mole, deltaH0 = -11.9 kcal/mole, and deltaS0 = +1.4 cal degree-1 mole-1. Measurement of the pH dependence of binding indicated that both thyroxine and triiodothyronine were bound maximally in the region of physiological pH, pH 6.8 to 7.7.

Binding Sites↗
PubMed1979

Adaptation to restricted intake of protein and energy.

Adult rats that maintained nitrogen balance on a diet containing 5% casein fed ad libitum were restricted to 70% of their normal food intake for 31 days. This resulted in a negative N balance, loss of body weight and increased activities of hepatic glutamic pyruvic transaminase and arginase--all of which persisted for 10 days. After this time there was no further weight loss, the negative N balance returned to equilibrium and the activities of the two enzymes returned to normal indicating adaptation to the dietary restriction. Radio-isotope studies with labelled methionine showed that dietary restriction led to an increase in the radioactivity of the liver and a decrease of that of the muscles indicating maintenance of liver protein at the expense of muscle protein. Resting oxygen consumption decreased by 34% after 20 days of dietary restriction and this would account for the adaptation observed.

Adaptation, Physiological↗
PubMed1979

Loss of nitroglycerin from aqueous solution into plastic intravenous delivery systems.

The mechanism of potential loss of nitroglycerin stored in plastic and glass containers was studied from an equilibrium and kinetic approach. Plastic strips equilibrated with dilute aqueous solutions of neat nitroglycerin showed that the drug was lost by absorption. Drug loss was followed by an electron-capture GLC assay. The same assay of control solutions in glass showed no drug loss in 48 hr at pH 5.7. The kinetics of nitroglycerin absorption and desorption were determined using synthesized 14C-labeled drug. Absorption can be quantified using a diffusion model, where the concentration in the aqueous phase falls with time. Curve fitting yielded an average diffusion coefficient in plastic of 2.05 x 10(-9) cm2/sec and a partition coefficient of 104 (plastic-water) at 30 degrees. Temperature-dependence studies of absorption showed that the diffusion coefficient followed an Arrhenius relationship with an energy requirement of 19.6 kcal/mole, whereas effects on the partition coefficient were negligible. Nitroglycerin desorption from plastic disks under sink conditions into water can be quantified by assuming a diffusion model where the concentration at the surface of a plane sheet remains constant. Nonlinear least-squares curve fitting generated a diffusion coefficient of 1.14 x 10(-9) cm2/sec for the desorption process at 30 degrees.

Absorption↗
PubMed1979

Analysis of anomalous pKb values for metiamide and atropine in the isolated stomach of the mouse.

1 In the isolated, lumen-perfused, stomach preparation of the mouse, metiamide was found by kinetic analysis to behave like a simple competitive antagonist of histamine-stimulated acid secretion. However, the pK(B) estimate of 5.08 was significantly lower than that found in guinea-pig atrium (6.0) or rat uterus (6.1) suggesting that H(2)-receptors might not be homogeneous.2 A similar analysis showed that atropine also behaved like a simple competitive antagonist of bethanechol-stimulated acid secretion and the estimated pK(B) (7.65) was significantly lower than the standard estimate of this parameter in guinea-pig ileum (9.0). Either the muscarinic cholinoceptors in mouse stomach were also anomalous or the preparation was introducing a systematic error. Lumen perfusion might distort this type of kinetic analysis by allowing steady-state conditions but not true equilibrium to develop at the receptor compartment due to loss of antagonist into the gastric secretion. Drug interactions at receptors in the muscle layers of the stomach would be expected to be much less sensitive to this error.3 When the atropine-bethanechol interaction was measured on the contraction of the isolated, lumen-perfused, stomach of the mouse the necessary conditions for simple competition were not met even though the sensitivity to atropine was obviously increased. The criteria for the expected simple competition were being obscured by events at low antagonist concentrations. Alterations in agonist or antagonist concentrations could be more or less eliminated so that physiological antagonism, perhaps by release of 5-hydroxytryptamine, was considered. This was supported, to some extent, by finding that, when stomachs from animals pretreated with reserpine were used, the kinetic analysis was normalized and gave a pK(B) of 8.99. Apparently, the muscarinic receptors in mouse stomach are homogeneous with those in other tissues.4 Therefore, we conclude that our results no more point to heterogeneity among histamine receptors than they point to differences in muscarinic cholinoceptors because this type of kinetic analysis can be readily distorted by special features of the measuring system.

Animals↗
PubMed1979

Errors in interpretation of data from equilibrium dialysis protein binding experiments.

In equilibrium dialysis protein binding experiments, the fraction of free or bound drug determined at equilibrium by dialysis of a patient plasma sample does not correspond to the drug concentration in the initial plasma sample, but to the drug concentration inside the plasma compartment of the dialysis apparatus at equilibrium. That fraction of free or bound drug corresponds to a lower total drug concentration than that in the initial plasma sample because of loss of drug due to passage of free drug into the buffer compartment in the equilibrium dialysis experiment. The magnitude of the difference between the initial drug concentration and the equilibrium drug concentration depends on the extent of drug binding and experimental conditions. If the initial total drug concentration in the plasma or serum sample as well as the fraction of drug bound at equilibrium as determined by radiotracer methods are known, then, using methods given in the text, the equilibrium drug concentration, the binding parameters corresponding to equilibrium conditions, and the free drug concentration in the initial plasma sample may be estimated.

Blood Proteins↗
PubMed1977

Stability of nuclear triiodothyronine binding sites.

Rat liver nuclei have recently been shown to possess limited, high affinity binding sites for triiodothyronine, only a fraction of which are believed to be filled in vivo. We have found that preincubation of nuclei in the absence of added triiodothyronine leads to a rapid decrease in binding capacity. This loss of binding sites is considerably faster at 37 C than at 4 C. On the other hand, once binding equilibrium is reached between nuclear bound and free triiodothyronine the level of binding does not change during the time in which a considerable loss of binding had occurred when nuclei were preincubated in the absence of hormone. Also the rate of dissociation of triiodothyronine from nuclei is slower than the rate of loss of binding sites during preincubation in the absence of added hormone. Thus, it appears as if unfilled sites are being lost during the preincubation period. Administration of cycloheximide or actinomycin D, inhibitors of protein and RNA synthesis, respectively, to rats caused a decrease in the amount of triiodothyronine which could be bound in the in vitro binding assay to liver nuclei.

Animals↗
PubMed1978

The minimum cottonseed protein required for nitrogen balance in women.

This study was designed to assess minimum amount of nitrogen from deglanded (LCP) and glandless (GSF) cottonseed protein required to maintain nitrogen balance in young adult women. Fourteen women aged 19 to 25 were divided into two groups, one group was fed LCP and the other GSF in a purified formula diet for the entire study. The protein level constituted approximately 15% of the total energy intake initially. After reaching and maintaining equilibrium, the protein level for each subject was decreased until that lowest level was found that would maintain the individual in nitrogen balance. Nitrogen status was calculated using the formula: Nitrogen Status = N Intake--N Output (Urinary + Fecal + other Obligatory Loss). Regression data for each subject was used to define nitrogen intake required to maintain equilibrium. The nitrogen intakes showed similar results for the two forms of cottonseed with a mean value of 0.106 g N per kg body weight to maintain equilibrium. The quality of cottonseed protein was between reported values in men for soybean and wheat protein.

Adult↗