The Effect of Temperature on the Survival In Vitro of Rabbit Spermatozoa Obtained from the Vas Deferens

1930 ◽  
Vol 7 (2) ◽  
pp. 201-219
Author(s):  
ARTHUR WALTON
Keyword(s):  
Body Temperature ◽  
Sex Ratio ◽  
Vas Deferens ◽  
Liquid Paraffin ◽  
The Body ◽  
Effect Of Temperature ◽  
Gaseous Exchange ◽  
Optimum Temperature ◽  
Rabbit Spermatozoa

1. A technique is described for the investigation of in vitro problems with spermatozoa removed from the vas deferens of the rabbit. The method involves the protection of the spermatozoa by means of liquid paraffin from evaporation of rapid gaseous exchange. 2. The survival of functional integrity (fertilizing capacity) has been shown to be a function of temperature and the effect of temperature has been studied over the range from 45° C. to 0° C. Above body temperature the spermatozoa are rapidly destroyed. At body temperature (40° C.) maximal survival is about 13 hours. As the temperature is lowered survival becomes increasingly prolonged until a maximum of 7 days is reached at 15°C. The curve over the range from 15° C. to 40° C. is only approximately exponential and it is doubtful whether an analogy can be drawn between the effect of temperature on the velocity with which the spermatozoa are destroyed, and the effect of temperature on the velocity of many biological reactions which follow approximately the van't Hoff and Arrhenius questions. Below the optimum temperature (10°-15°C.) the velocity of destruction is acclerated by fall of temperature. 3. The sex-ratio of the resulting offspring is not significantly altered by keeping the spermatozoa outside the body.

The Effect of Temperature on the Survival In Vitro of Rabbit Spermatozoa Obtained from the Vagina

1930 ◽  
Vol 7 (2) ◽  
pp. 175-195
Author(s):  
J. HAMMOND
Keyword(s):  
Birth Weight ◽  
Body Temperature ◽  
Sex Ratio ◽  
Room Temperature ◽  
Effect Of Temperature ◽  
Optimum Temperature ◽  
Average Size ◽  
Rabbit Spermatozoa ◽  
Duration Of Pregnancy

1. The time during which spermatozoa, obtained from the vagina of the female rabbit after service, retain their fertilising power when kept in vitro at diferent temperatures has been determined. 2. At 35° C., or just below body temperature, young are obtained up to 14 hours at 10° C. up to 96 hours and at 0° C. up to 16 hours, there being a well-marked optimum temperature for survival. 3. Not only does the percentage of animals fertile fall with increase in the length of time the semen is kept, but also the average size of the litter decreases in the small litters so obtained the birth weight is increased considerably and the duration of pregnancy slightly lengthened. 4. The percentage of spermatozoa motile, when examined at room temperature is a fairly good indication of the percentage fertility. 5. The sex-ratio is not materially affected by keeping the sperm. 6. Sterility due to adherent tubes was frequent during the course of the experiments. 7. These results with semen obtained from the vagina are compared with those obtained in a parallel series direct from the epididymis of the male under paraffin

Digestion in Ascidians and the Influence of Temperature

1929 ◽  
Vol 6 (3) ◽  
pp. 275-292
Author(s):  
N. J. BERRILL
Keyword(s):  
Enzyme Activity ◽  
Body Temperature ◽  
Digestive Enzymes ◽  
Alimentary Canal ◽  
The Body ◽  
Maximum Efficiency ◽  
Bile Pigment ◽  
Optimum Temperature ◽  
Different Temperatures ◽  
Pass Through

1. The mechanism of feeding and digestion in the Pyurid Ascidians Tethyum pyriforme americanum and Boltenia ovifera is described. 2. The structure and histology of the "liver" is described and it is shown that it is primarily an organ of secretion. 3. It is found that the only digestive enzymes are those poured into the gut by the liver, and consist of a powerful amylase, a protease, a very weak lipase, and also an invertase, a maltase, and a lactase. 4. The brownish pigment of the liver gives reactions with acids somewhat like those of bile pigment. There is no trace of bile salts, however, nor of cholesterol. 5. The amylase has an activity range from pH 6.0 topic pH 8.5 with an optimum near pH 7.5. The protease is active from pH 6.0 to above pH 10.0. A similar protease is secreted by Molgula citrina and Ascidia prunum. 6. The relative strengths of the amylase and protease are compared, the amylase being very much the stronger. 7. While experiments of brief duration indicate an optimum temperature for enzyme activity above 40° C, the more prolonged the experiments the lower does the optimum become. Whatever the optimum may be after an experiment of 2 hours' duration, it falls about 20° C. during the next 45 hours, if the experiments be so prolonged. 8. At 15° C. and at 10° C. the food takes about 35 and 55 hours respectively to pass through the alimentary canal, and at 50 C. somewhere between 70 and 90 hours. These temperatures approximately cover the normal range in temperature of the environment, and therefore of the animal itself. 9. From experiments lasting 33 hours the optimum temperature for enzyme activity was found to be about 17° C.; that is, within one or two degrees of the body temperature. From experiments lasting 57 hours the optimum temperature was found to be about 13° C ; that is, within three degrees of the body temperature. 10. These temperature optima not only represent the relative amounts of substrate converted at different temperatures, but also represent the absolute amounts converted and convertible. 11. The enzymes, amylase and protease, are two-thirds to three-quarters destroyed during their period of activity within the alimentary canal of the animal, and in order to utilise the remainder the digestion mixture would have to be retained within the canal for twice as long a time. 12. Therefore it seems probable that the organism in making such a compromise between a high activity of the enzyme and its economical use is working to a maximum efficiency; and it is possible that a permanent increase in the stability of the digestive enzymes would be turned to advantage through a more prolonged retention of the food within the gut.

scholarly journals Impact of Hypothermia on Differentiation and Maturation of Neutrophils

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 2393-2393
Author(s):  
Yusuke Torikoshi ◽  
Asumi Yokota ◽  
Naoka Kamio ◽  
Atsushi Sato ◽  
Tsukimi Shouji ◽  
...  
Keyword(s):  
Body Temperature ◽  
Host Defense ◽  
Research Funding ◽  
Molecular Mechanisms ◽  
Environmental Temperature ◽  
Cecal Ligation ◽  
The Body ◽  
Neutrophil Differentiation ◽  
The Impact

Abstract Accumulating evidence has suggested that low body temperature is associated with the risk of infection. Unintentional drops in the body temperature known as "accidental hypothermia" are occasionally accompanied with infections. Patients under therapeutic hypothermia for post-cardiac arrest care are also susceptible to infections. In addition, secondary hypothermia caused by severe sepsis is significantly associated with higher mortality. These observations suggest the negative impact of hypothermia on host defense. Neutrophils are continuously produced in the bone marrow (BM) and supplied to the peripheral blood (PB) or tissues, where they fight against microorganisms. In addition to the neutrophil functions, sufficient supply of neutrophils is a critical determinant of host defense. However, little is known about the impact of hypothermia on granulopoiesis, the process of neutrophil production in the BM. In this study, we investigated the changes in granulopoiesis under hypothermic conditions. We first analyzed the neutrophils in the PB of mice exposed to low environmental temperature (4 °C). Under this condition, rectal temperature of the mice significantly declined from 36.7±0.4 °C to 35.5±0.4 °C. After 72-hour exposure to the low environmental temperature, PB neutrophil counts were significantly decreased. In order to understand the reason for the decrease, we analyzed their BMs by flow cytometry. Previously we developed a unique strategy to divide cells undergoing granulopoiesis into 5 subpopulations based on the expression of c-kit and Ly6G, which reflect successive differentiation/maturation from #1 (c-kithi Ly6G-) to #5 (c-kit- Ly6Ghi) (Satake S and Hirai H et al. J Immunol, 2012). In BM cells of the mice exposed to the low environmental temperature, a significant decrease in mature neutrophils (#5) and a significant increase in cellular intermediates (#3 and #4) were observed, while total BM cell numbers were unchanged. In order to clarify whether these changes were cell-intrinsic or -extrinsic, total BM cells were cultured in vitro at either 35 °C or 37 °C in the presence of G-CSF. Flow cytometric analysis of these cultured BM cells at 72 hours revealed the increase in the intermediates (#2 to #4) and a decrease in the mature subpopulation (#5), suggesting that these alterations were cell-intrinsic phenomena. When neutrophil precursors (#1 or #2) were purified by cell sorter and subjected to in vitro culture at 35 °C for 48 hours, the number of resultant mature neutrophils (#5) were significantly less than those induced at 37 °C. These results clearly indicate that hypothermia delayed neutrophil differentiation/maturation. Interestingly, mice with sepsis induced by cecal ligation and puncture (CLP) accompanied with lower body temperature revealed significantly fewer PB granulocytes and shorter survival when compared to those mice which maintained normal body temperature after CLP. In order to understand the molecular mechanisms underlying the differentiation/maturation delay induced by hypothermia, we performed RNA sequencing of purified neutrophil precursors (#2) after 24-hour culture either at 35 °C or 37 °C. Interestingly, we found alterations in amino acid metabolic pathways and target genes of C/EBP, which is the transcription factor family required for granulopoiesis and cellular metabolism. Collectively, these results indicate hypothermia causes neutropenia through delayed neutrophil differentiation/maturation. We are currently analyzing metabolic changes to understand more precise molecular mechanisms by which hypothermia regulates granulopoiesis. This study will facilitate the understanding of host defense at low body temperature, and shed novel insight into the management of hypothermia in patients. Disclosures Kashiwagi: Takara Bio Inc.: Employment. Hirai:Kyowa Hakko Kirin: Research Funding; Novartis Pharma: Research Funding.

scholarly journals Effects of adhesive systems at different temperatures on the shear bond strength of orthodontic brackets

2019 ◽  
Vol 13 (2) ◽  
pp. 103-108
Author(s):  
Serdar Akarsu ◽  
Suleyman Kutalmış Buyuk ◽  
Ahmet Serkan Kucukekenci
Keyword(s):  
Body Temperature ◽  
Bond Strength ◽  
Shear Bond Strength ◽  
Testing Machine ◽  
The Body ◽  
Orthodontic Brackets ◽  
Effect Of Temperature ◽  
Adhesive Systems ◽  
Significant Difference ◽  
Different Temperatures

Background. The temperature might affect the physical and mechanical properties of adhesive materials by reducing the polymerization rate. The present study aimed to evaluate the effect of temperature on the shear bond strength of metallic orthodontic brackets using various adhesive resin systems. Methods. Extracted human premolar teeth were randomly assigned to 8 groups (n=10) for bonding with the two available orthodontics adhesive systems (Transbond XT and NeoBond) at different temperatures: refrigeration temperature (4°C), room temperature (20°C), human body temperature (36°C) and high temperature (55°C). The shear bond strength (SBS) test was performed using a universal testing machine at a crosshead speed of 0.5 mm/min. The adhesive remnant index (ARI) was assigned to the fractured orthodontic brackets. Data were analyzed with one-way ANOVA, post hoc Tukey tests and independent t-test. Results. Transbond XT exhibited higher SBS values compared to Neobond at all the tested temperatures; however, a statistically significant difference was not observed (P>0.05). The SBS results were minimum at 4°C and maximum at 36°C in both the adhesive groups (P<0.05). Conclusion. Pre-heating orthodontic adhesives up to the body temperature prior to bonding the brackets in orthodontic treatment increased the bond strength of orthodontic brackets.

Alteration of activation energy of reaction in the catalase of human erythrocyte by cimetidine, an in vitro thermokinetics study

2020 ◽  
Vol 09 ◽  
Author(s):  
Dariush Minai-Tehrani
Keyword(s):  
Activation Energy ◽  
Human Erythrocyte ◽  
Cell Injury ◽  
Gastrointestinal Diseases ◽  
Maximum Activity ◽  
The Body ◽  
Effect Of Temperature ◽  
Histamine H2 Receptor ◽  
In Cells

Background: Hydrogen peroxide is normally formed during the metabolic pathway of the body. It is a toxic compound for vital cells, which can oxidize many macromolecules and cause damage in cells. Catalase can degrade H2O2 in cells and prevent cell injury. Cimetidine is a histamine H2 receptor blocker which decreases the release of stomach acid and is used for gastrointestinal diseases. Cimetidine inhibited catalase by mixed inhibition. Objective: In this study, effect of temperature on the binding of cimetidine to human erythrocyte catalase was investigated and kinetic factors of the binding were determined. Results: Dixon plot confirmed the mixed type of inhibition and determined the Ki of the drug. Maximum activity of the enzyme was observed at 30oC. Arrhenius plot demonstrated that the activation energy of the enzyme reaction in the absence and presence of cimetidine was about 4.7 and 8.13 kJ/mol, respectively. Temperature coefficient (Q30-40) was determined as about 1.11 and 1.09 in the absence and presence of cimetidine. Conclusion: Cimetidine was able to increase the activation energy of the reaction of catalase, which confirmed the inhibition of the enzyme based on the kinetic results.

The effect of temperature, age and density of gametocytes, and changes in gas composition on exflagellation of Leucocytozoon simondi

1973 ◽  
Vol 51 (6) ◽  
pp. 577-587 ◽  
Author(s):  
N. R. Roller ◽  
S. S. Desser
Keyword(s):  
Inverse Relationship ◽  
The Body ◽  
Effect Of Temperature ◽  
Gas Composition ◽  
Fresh Blood ◽  
Infected Blood ◽  
Per Se ◽  
Time Required ◽  
Made In

The rate of initiation of exflagellation of microgametocytes of Leucocytozoon simondi was studied in relation to temperature, age and density of gametocytes, and changes in gas composition. Observations were made in vitro through examination of fresh blood, and thin blood films were prepared at appropriate intervals. An inverse relationship between temperature and the time required for initiation of ex-flagellation was demonstrated. There was a decrease in the time required for initiation of exflagellation as the temperature increased from 15 to 26C. Between 26 and 40C exflagellation usually occurred in 1–1½ min. Exflagellation at 40C, which approximates the body temperature of the host, indicates that a drop in temperature per se is not necessary for the initiation of exflagellation. Gametocytes appear to be capable of exflagellation for about 5 days postmaturity. Differences in density of parasitemia do not affect the time for initiation of exflagellation. The presence of O2 and a decrease in CO2 are important stimuli for exflagellation. The effect of the above factors on the initiation of exflagellation is discussed in relation to the uptake of infected blood by the simuliid vector of the parasite, and compared with the situation in related Haemosporina

Temperature dependence of in vitro androgen production in testes from hibernating ground squirrels, Spermophilus lateralis

1987 ◽  
Vol 65 (12) ◽  
pp. 3020-3023 ◽  
Author(s):  
Brian M. Barnes ◽  
Paul Licht ◽  
Irving Zucker
Keyword(s):  
Ground Squirrel ◽  
Temperature Compensation ◽  
Laboratory Mouse ◽  
Ground Squirrels ◽  
The Body ◽  
Effect Of Temperature ◽  
Dependent Manner ◽  
Spermophilus Lateralis ◽  
Dose Dependent

The effect of temperature on the in vitro androgen secretion of testes from hibernating ground squirrels was measured in response to stimulation by luteinizing hormone (LH). We wished to determine whether hibernating ground squirrels can maintain responsiveness of gonads while at the low body temperatures of torpor. In gonads incubated at 32 °C, secretion of testosterone increased in a dose-dependent manner in response to ovine-LH or ground squirrel pituitary homogenate. This responsiveness was reduced at 20 and 9 °C and absent at 5 °C, the temperature that most closely approximates the body temperature of torpid ground squirrels. This temperature sensitivity was similar to that in the nonhibernating laboratory mouse. Superfusion of ground squirrel testes revealed a lag of testosterone secretion in response to LH and, additionally, an ability of testes to secrete testosterone after being only briefly exposed to ovine-LH while at 5 °C. These results provide evidence against a hypothesis of temperature compensation that would allow continued testis function during torpor, and support a previous study which indicated that gonadal growth is restricted to intervals of normothermy during and after the hibernation season.

scholarly journals Temperature Effects on Haemolymph Acid-Base Status In Vivo and In Vitro in the Two-Striped Grasshopper Melanoplus Bivittatus

1988 ◽  
Vol 140 (1) ◽  
pp. 421-435 ◽  
Author(s):  
JON M. HARRISON
Keyword(s):  
Body Temperature ◽  
Carbonic Acid ◽  
Temperature Shift ◽  
Effect Of Temperature ◽  
Locomotory Activity ◽  
Acid Base ◽  
Protein Dissociation ◽  
Acid Base Status

In this study, I examine the effect of temperature on haemolymph acid-base status in vivo and in vitro in the two-striped grasshopper Melanoplus bivittatus. Melanoplus bivittatus experience wide (up to 40 °C) diurnal body temperature fluctuations in the field, but maintain body temperature relatively constant during sunny days by behavioural thermoregulation. Haemolymph pH was statistically constant (7.12) between 10 and 25°C, but decreased by −0.017 units °C− from 25 to 40°C. Relative alkalinity and fractional protein dissociation were conserved only at body temperatures at which feeding and locomotory activity occur, above 20°C. Haemolymph total CO2 (Ctot) increased from 10 to 20°C and decreased from 20 to 40°C. Haemolymph Pco2 increased from 10 to 20°C and was statistically constant between 20 and 40°C. Carbonic acid pKapp in haemolymph was 6.122 at 35°C, and decreased with temperature by −0.0081 units°C−1. Haemolymph buffer value averaged −35mequivl−1pHunit−1. Haemolymph pH changes with temperature were small (less than −0.004 units°C−1) in vitro at constant Pco2. Therefore, passive physicochemical effects cannot account for the pattern of acid-base regulation in vivo. The temperature shift from 10 to 20°C was accompanied by a net addition of 4.2-6.2 mmoll−1 of bicarbonate equivalents to the haemolymph. The temperature shift from 20 to 40°C was accompanied by a net removal of 10–14 mmoll−1 of bicarbonate equivalents from the haemolymph. Haemolymph acid-base regulation in vivo during temperature changes is dominated by active variation of bicarbonate equivalents rather than by changes in Pco2 as observed for most other air-breathers.

CONGENITAL TOXOPLASMOSIS

PEDIATRICS ◽  
1949 ◽  
Vol 4 (4) ◽  
pp. 432-442
Author(s):  
SVEN GARD ◽  
J. HENNING MAGNUSSON ◽  
F. WAHLGREN ◽  
GUNNAR GILLE
Keyword(s):  
Spinal Cord ◽  
Cerebrospinal Fluid ◽  
Body Temperature ◽  
Liver Biopsy ◽  
Neutralization Test ◽  
High Titer ◽  
Congenital Toxoplasmosis ◽  
The Body ◽  
The Brain

An account is given of congenital toxoplasmosis in a child who died at the age of 43 days. The patient, who was somnolent from birth, showed the following symptoms: bilateral microphthalmia and chronic bilateral uveitis; considerable hydrocephalus internus, mainly symmetric, cerebral calcifications and pronounced typical changes in the cerebrospinal fluid, hypoprothrombinemia and eosinophilia; enlargement of the liver and spleen; marked lability of the body temperature with wide variations. The postmortem findings, both macroscopic and microscopic, were typical in every respect, with pronounced necrotic encephalitis in the cerebrum and characteristic foci of granulomata in the brainstem and the spinal cord. Toxoplasma in the form of pseudocysts were demonstrated in the affected parts of the brain. Typical Toxoplasma were isolated from the spinal fluid on three occasions, from material obtained by liver biopsy and from pieces of brain and spleen removed at autopsy. Serum from the patient as well as from the mother gave a positive neutralization test in rabbits. The in vitro dye test according to Sabin and Feldman yielded a positive result with a high titer value. The strain of Toxoplasma isolated ("G. L.") seems to be serologically identical with the American strains "RH" and "LM."

Cerebral Energy Requirement of Neonatal Rats

1957 ◽  
Vol 188 (2) ◽  
pp. 277-280 ◽  
Author(s):  
Frederick E. Samson ◽  
Nancy A. Dahl
Keyword(s):  
Body Temperature ◽  
Survival Time ◽  
Energy Requirement ◽  
Iodoacetic Acid ◽  
The Body ◽  
Effect Of Temperature ◽  
Neonatal Rats ◽  
Survival Times ◽  
Respiratory Centers ◽  
Respiratory Movements

The survival times of neonatal rats in nitrogen with and without injected iodoacetic acid and at diverse ages and temperatures are presented. It is shown that the survival time in nitrogen is greatly shortened if iodoacetic acid has been injected. Also, in iodoacetic acid treated rats the survival time is decreased with the daily development of the animal; the survival time is lengthened by a decrease in body temperature; the effect of temperature decreases with the daily development of the animal; the logarithm of the survival time has a linear relationship with the body temperature. It is concluded that these survival times are a measure of the energy requirement of the respiratory centers and the influence of age and temperature upon the requirement. A calculation is made which indicates that a deficiency of one micromole of energy-rich phosphate per gram of tissue in the respiratory centers results in the cessation of respiratory movements.

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