The trypanosomes of Ranidae. I. The effects of temperature and diurnal periodicity on the peripheral parasitaemia in the bullfrog (Rana catesbeiana Shaw)

1969 ◽  
Vol 47 (3) ◽  
pp. 283-288 ◽  
Author(s):  
J. E. Bardsley ◽  
R. Harmsen
Keyword(s):  
Metabolic Activity ◽  
Low Temperatures ◽  
Elevated Temperatures ◽  
Rana Catesbeiana ◽  
Insect Vector ◽  
Short Term ◽  
Type D ◽  
Effects Of Temperature ◽  
Morph Type

The peripheral parasitaemia of the Trypanosoma rotatorium complex in the bullfrog (Rana catesbeiana) is markedly affected by temperature. Over the long term, high temperatures are always coincident with high peripheral parasitaemia and vice versa; over the short term, increases in temperature bring about a corresponding increase in parasite level, and vice versa. A distinct diurnal cyclicity in parasitaemic level is found for one morph (type D) at elevated temperatures (26 °C); no such cyclicity was apparent at low temperatures (10 °C). Other morphs did not display any cyclicity at either temperature. It is proposed that the control of peripheral parasitaemia is due to changes in the level of metabolic activity of the host.Natural selection will favor any behavioral or growth pattern among trypanosomes which results in an increased peripheral parasitaemia at times and under conditions of optimal host–vector contact. The present results suggest an optimal host–vector contact for basking frogs. The possibility of an insect vector is discussed.

Effects of Temperature on Responses of the Gonads of Green Sunfish (Lepomis cyanellus) to Treatment with Carp Pituitaries and Testosterone Propionate

1973 ◽  
Vol 30 (7) ◽  
pp. 905-912 ◽  
Author(s):  
Calvin M. Kaya
Keyword(s):  
Low Temperatures ◽  
Elevated Temperatures ◽  
Testosterone Propionate ◽  
Lepomis Cyanellus ◽  
Pituitary Glands ◽  
Effects Of Temperature ◽  
Gonadal Recrudescence ◽  
Green Sunfish ◽  
The Brain ◽  
Stimulation Of

Previous investigations have demonstrated that stimulation of gonadal recrudescence in the green sunfish (Lepomis cyanellus) depends on the concurrent presence of long photoperiods (15 hr) and elevated temperatures (> 15 C). The present investigation indicates that recrudescence can be stimulated in seasonally regressed ovaries and testes by injections of a crude extract of fish pituitary glands, and in testes by testosterone propionate, but only under elevated temperature. The low temperatures that block gonadal responses to long photoperiods also effectively prevent gonadal responses to administered hormones. These observations indicate that the responsiveness of the gonads of this species to stimulating hormones is markedly modified by temperature; however, the results do not obviate the possibility that secretion of gonadotropins by the brain–pituitary system may also be affected.

Influence of temperature on the activity of anammox granular biomass

2016 ◽  
Vol 73 (10) ◽  
pp. 2518-2525 ◽  
Author(s):  
D. Sobotka ◽  
K. Czerwionka ◽  
J. Makinia
Keyword(s):  
Removal Rate ◽  
Batch Reactor ◽  
Effect Of Temperature ◽  
Short Term ◽  
Temperature Range ◽  
Batch Tests ◽  
Different Temperatures ◽  
Effects Of Temperature ◽  
Granular Biomass

The aim of this study was to determine a short-term and long-term effect of temperature on the anammox rate and determination of temperature coefficients in the Arrhenius and Ratkowsky equations. The short-term effects of temperature on the anammox granular biomass were investigated in batch tests at ten different temperatures in the range of 10–55 °C. The maximum overall nitrogen removal rate of 1.3 gN gVSS−1·d−1 was observed at 40 °C (VSS: volatile suspended solids). The minimum rate, close to 0 gN gVSS−1·d−1, was observed for the limits of the analyzed temperature range (10 and 55 °C). The activity tests carried out at 55 °C showed an irreversible loss of the activity due to the observed biomass lysis. Subsequently to the batch tests, a sequencing batch reactor (SBR) was operated at different temperatures (from 30 to 11 °C) to determine the long-term effects of temperature. The system was successfully operated at 15 °C, but when temperature was decreased to 11 °C, nitrite started to accumulate and the system lost its stability. The temperature coefficient (θ) was 1.07 for the batch tests carried out in the temperature range of 10–40 °C. In contrast, during the long-term SBR operation, substantially different θ had to be estimated for two temperature ranges, 1.07 (T = 15–30 °C) and 1.65 (T = 11–15 °C).

Stomatal conductance in Cucumis sativus upon short-term and long-term exposures to low temperatures

2012 ◽  
Vol 59 (5) ◽  
pp. 696-699 ◽  
Author(s):  
E. N. Ikkonen ◽  
T. G. Shibaeva ◽  
M. I. Sysoeva ◽  
E. G. Sherudilo
Keyword(s):  
Stomatal Conductance ◽  
Cucumis Sativus ◽  
Low Temperatures ◽  
Short Term

scholarly journals Factors, determining the origin of debris flows on the southern slopes of the Crimean Mountains

Geografie ◽  
2015 ◽  
Vol 120 (1) ◽  
pp. 50-63
Author(s):  
Karel Šilhán ◽  
Tomáš Pánek ◽  
Jan Hradecký
Keyword(s):  
Time Series ◽  
Debris Flow ◽  
Low Temperatures ◽  
Debris Flows ◽  
Pinus Nigra ◽  
Short Term ◽  
Crimean Mountains ◽  
Lack Of Information ◽  
Triggering Factor

There is a lack of information about enabling and triggering factors of debris flows in the densely populated coastal slopes of the Crimean Mountains. In such respect, it is useful to reconstruct a chronology of historical debris flow events and correlate them with time series of relevant meteorological characteristics. We utilized dendrogeomorphological methods using 566 individuals of Pinus nigra for inferring age of 215 debris flow events. The oldest event is dated to 1701 and the highest decadal frequency of debris flows (20 events) is determined to 1940s. Long periods with anomalously low temperatures generating sufficient amount of debris are a major factor enabling debris flow. The dominant triggering factor for regional (multiply) debris flow events are long-term periods with above-average precipitations, but local (isolated) events are more related to short-term periods (~one month) with above-average precipitations.

scholarly journals The effect of acclimation to constant temperatures, pollution of food by heavy metals and short-term fasting on the metabolic activity of <i>Glomeris balcanica</i> (Diplopoda: Glomeridae)

Web Ecology ◽  
2000 ◽  
Vol 1 (1) ◽  
pp. 11-19 ◽  
Author(s):  
G. P. Stamou ◽  
G. Karris ◽  
M. A. Tsiafouli ◽  
E. M. Papatheodorou ◽  
M. D. Argyropoulou
Keyword(s):  
Metabolic Activity ◽  
Thermal Response ◽  
Compensatory Mechanism ◽  
Respiratory Metabolism ◽  
Short Term ◽  
Temperature Range ◽  
Metabolic Recovery ◽  
Optimal Temperature Range ◽  
Increasing Temperature

Abstract. Changing temperature regime has an important effect on the respiratory metabolism of Glomeris balcanica. A left skewing response of animals to increasing temperature is revealed and modeled. Acclimation from fluctuating to constant temperatures depresses metabolism through a three-step process. Short-term acclimation results in strongly depressed metabolism, mid-term acclimation induces metabolic recovery, whereas long-term acclimation results in an irreversible decline of metabolic activity. Heavy metal burdens of food do not affect the left skewing thermal response of animals, although they depress metabolic levels at the high temperature range, shorten tolerance ranges by shifting down the upper tolerance threshold, enlarge optimal temperature range (metabolic constancy) and stimulate the faster activation of the metabolic compensatory mechanism. Finally, no effect of short-term fasting on respiration was detected.

scholarly journals Increased concentrations of haemolymph Mg2+ protect intracellular pH and ATP levels during temperature stress and anoxia in the common shrimp

1997 ◽  
Vol 200 (4) ◽  
pp. 785-792 ◽  
Author(s):  
F J Sartoris ◽  
H O Pörtner
Keyword(s):  
Protective Effect ◽  
Intracellular Ph ◽  
Threshold Concentration ◽  
Short Term ◽  
Anoxic Conditions ◽  
Muscle Tissues ◽  
The Common ◽  
Effects Of Temperature ◽  
Lactate Levels

The effects of temperature (0, 5, 10, 15 and 20 &deg;C) and of anoxia (at 5 &deg;C) on extracellular Mg2+ concentration ([Mg2+]e), intracellular pH (pHi) and ATP and lactate levels were investigated in intermoult adults of the common shrimp Crangon crangon. All animals caught in summer (summer animals) showed a slight but significant increase in [Mg2+]e at low temperatures. In contrast, at every temperature tested, a few of the animals caught in winter (winter animals) showed elevated [Mg2+]e during short-term (4 h) but not during long-term (6 days) incubations. The reasons for the overshoot in Mg2+ concentrations in individual animals remain unexplained, but a protective effect of extracellular Mg2+ on intracellular pH and on ATP concentrations was visible at haemolymph Mg2+ concentrations above 15 mmol l-1. The influence of high extracellular [Mg2+] on pHi and intracellular ATP and lactate levels under normoxic and anoxic conditions was tested using an incubation medium containing 150&shy;250 mmol l-1 Mg2+. When haemolymph Mg2+ levels were manipulated by exposure of the animal to high levels of Mg2+ in the external medium, animals with a haemolymph [Mg2+] below the threshold concentration of 15 mmol l-1 had significantly lower values of intracellular pH than animals with haemolymph [Mg2+] above 15 mmol l-1. In addition, the elevation of haemolymph [Mg2+] by incubation in high-[Mg2+] water prevented the drop in pHi and the rise in lactate levels induced by anoxia. The protective effect of high levels of extracellular Mg2+ did not depend upon the [Ca2+]/[Mg2+] ratio but only on [Mg2+]e. However, experiments with isolated muscle tissues showed no dependence of muscle intracellular pH on [Mg2+]e under both normoxic and anoxic conditions, leading to the conclusion that the protective effect is evoked via a central, possibly anaesthetising, effect of high [Mg2+]e. The dependence of pHi and muscle [ATP] on extracellular [Mg2+] resembles the protective effect of high Mg2+ levels on the post-ischaemic mammalian heart.

scholarly journals Trans-cinnamaldehyde potently kills Enterococcus faecalis biofilm cells and prevents biofilm recovery

2020 ◽  
Author(s):  
Islam A. A. Ali ◽  
Becky P. K. Cheung ◽  
Jukka. P. Matinlinna ◽  
Celine M. Lévesque ◽  
Prasanna Neelakantan
Keyword(s):  
Antibacterial Activity ◽  
Enterococcus Faecalis ◽  
Metabolic Activity ◽  
Root Canal ◽  
Viable Cell ◽  
Nosocomial Pathogen ◽  
Short Term ◽  
Cell Counts ◽  
First Time

AbstractEnterococcus faecalis is a biofilm-forming, nosocomial pathogen that is frequently isolated from failed root canal treatments. Contemporary root canal disinfectants are ineffective in eliminating these biofilms and preventing reinfection. As a result, there is a pressing need to identify novel and safe antibiofilm molecules. The effect of short-term (5 and 15 min) and long-term (24 h) treatments of TC on the viability of E. faecalis biofilms was compared with currently used root canal disinfectants. Treatment for 15 min with TC reduced biofilm metabolic activity as effective as 1% sodium hypochlorite and 2% chlorhexidine. Treatment with TC for 24 h was significantly more effective than 2% chlorhexidine in reducing the viable cell counts of biofilms. This serendipitous effect of TC was sustained for 10 days under growth-favoring conditions. For the first time, our study highlights the strong antibacterial activity of TC against E. faecalis biofilms, and notably, its ability to prevent biofilm recovery after treatment.

scholarly journals Larval developmental temperature and ambient temperature affect copulation duration in a seed beetle

Behaviour ◽  
2018 ◽  
Vol 155 (1) ◽  
pp. 69-82 ◽  
Author(s):  
R. Vasudeva ◽  
D.C. Deeming ◽  
P.E. Eady
Keyword(s):  
Ambient Temperature ◽  
Callosobruchus Maculatus ◽  
Copulation Duration ◽  
Short Term ◽  
Developmental Temperature ◽  
Effects Of Temperature ◽  
Kinetic Effects ◽  
Development Temperature ◽  
Copulatory Behaviour

Abstract The effects of temperature on cellular, systemic and whole-organism processes can be short-term, acting within seconds or minutes of a temperature change, or long-term, acting across ontogenetic stages to affect an organism’s morphology, physiology and behavioural phenotype. Here we examine the effect of larval development temperature on adult copulatory behaviour in the bruchid beetle, Callosobruchus maculatus. As predicted by temperature’s kinetic effects, copulation duration was longest at the lowest ambient temperature. However, where ambient temperature was fixed and developmental temperature experimentally varied, males reared at the highest temperature were least likely to engage in copulation, whilst those reared at the lowest temperature copulated for longer. Previous research has shown males reared at cooler temperatures inseminate fewer sperm. Thus, in this species longer copulations are associated with reduced sperm transfer. We argue that knowledge of preceding ontogenetic conditions will help to elucidate the causes of variation in copulatory behaviour.

scholarly journals Effects of Cryopreservation on Cell Metabolic Activity and Function of Biofabricated Structures Laden with Osteoblasts

Materials ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1966 ◽  
Author(s):  
Laura G. Hernández-Tapia ◽  
Zdenka Fohlerová ◽  
Jan Žídek ◽  
Marco A. Alvarez-Perez ◽  
Ladislav Čelko ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Metabolic Activity ◽  
Normal Values ◽  
Short Term ◽  
Beta Tricalcium Phosphate ◽  
Biological Responses ◽  
Biological Aspects ◽  
And Function ◽  
High Degree

Biofabrication and maturation of bone constructs is a long-term task that requires a high degree of specialization. This specialization falls onto the hierarchy complexity of the bone tissue that limits the transfer of this technology to the clinic. This work studied the effects of the short-term cryopreservation on biofabricated osteoblast-containing structures, with the final aim to make them steadily available in biobanks. The biological responses studied include the osteoblast post-thawing metabolic activity and the recovery of the osteoblastic function of 3D-bioprinted osteoblastic structures and beta tricalcium phosphate (β-TCP) scaffolds infiltrated with osteoblasts encapsulated in a hydrogel. The obtained structures were cryopreserved at −80 °C for 7 days using dimethyl sulfoxide (DMSO) as cryoprotectant additive. After thawing the structures were cultured up to 14 days. The results revealed fundamental biological aspects for the successful cryopreservation of osteoblast constructs. In summary, immature osteoblasts take longer to recover than mature osteoblasts. The pre-cryopreservation culture period had an important effect on the metabolic activity and function maintain, faster recovering normal values when cryopreserved after longer-term culture (7 days). The use of β-TCP scaffolds further improved the osteoblast survival after cryopreservation, resulting in similar levels of alkaline phosphatase activity in comparison with the non-preserved structures. These results contribute to the understanding of the biology of cryopreserved osteoblast constructs, approaching biofabrication to the clinical practice.

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