scholarly journals In vitro biology of pigeon louse Colpocephalum turbinatum (Amblycera: Phthiraptera)

2018 ◽  
Vol 10 (2) ◽  
pp. 770-772
Author(s):  
Satyapal Singh Rana ◽  
S. K. Bhardwaj ◽  
Arun Kumar Saxena
Keyword(s):  
Relative Humidity ◽  
Incubation Period ◽  
Adult Female ◽  
Present Report ◽  
In Vitro Rearing ◽  
Vitro Biology

In vitro rearing of amblyceran Phthiraptera is a challenging task. A look on the literature reveals that negligible information exists on the in vitro bionomics of avian Amblycera. Present report furnishes information on the in vitro biology of an amblyceran louse, Colpocephalum turbinatum, reared at 35 ± 1˚C, 75-82% Relative Humidity, at feather diet. The incubation period of the eggs of louse was determined as 5.37±0.67 days. The duration of first, second and third nymphal instars remained 5.04±0.65, 5.12±0.89 and 5.0±0.57 days, respectively. The longevity of adult female (13.04 ± 3.67 days) was comparatively longer than that of males (9.6±2.87 days). An adult female laid an average of 0.63 egg/day in vitro condition (35±1oC and 75-82% RH, at feather diet).

scholarly journals Effect of Larval Food Amount on in vitro Rearing of Indo-Malayan Stingless Bee Queen, Heterotrigona itama (Hymenoptera: Apidae; Meliponini)

2021 ◽  
Vol 50 (10) ◽  
pp. 2859-2867
Author(s):  
Nurul Izdihar Razali ◽  
Shamsul Bahri Abd Razak ◽  
Fatimah Hashim ◽  
Nurul Wahida Othman ◽  
Wahizatul Afzan Azmi
Keyword(s):  
Relative Humidity ◽  
Native Species ◽  
Stingless Bees ◽  
Large Scale ◽  
Survival Curve ◽  
Stingless Bee ◽  
Larval Food ◽  
In Vitro Rearing ◽  
Short Period

The demand for stingless bee colonies in Malaysia has considerably increased due to the rapid advance of meliponiculture in using the stingless bees as agricultural pollinators, as well as the commercialization of stingless bee products (i.e. honey, bee bread and propolis). Thus, in vitro queen rearing for a large scale and rapid colony multiplication must be developed in order to fulfil the public requirements in a short period. Little is known about the in vitro rearing of native stingless bee queen, Heterotrigona itama. Therefore, in this study, we investigated the amount of larval food required by H. itama queen by comparing three different amounts of larval food, viz., 100 µL, 120 µL and 150 µL. All treatments were controlled under 100% relative humidity for the first 6 days, and 75% relative humidity for the rest of larval development until queen adult emergence, under 30 °C incubator temperature. The results showed that larvae of H. itama treated with the highest amount of larval food (150 µL) led to 78% of the queen’s emergence, whereas larvae treated with 120 µL and 100 µL of larval food resulted in 40% and 0% of queen emergence. The dynamic survival curve showed that most of the larvae died before the pupation phase and reached constant stability afterward. The queen’s body and abdominal length were significantly greater than wild workers. Microscopy analysis showed that in vitro queen had well-developed reproductive system with a huge ovary and spermatheca, whereas wild worker had much smaller ovary without spermatheca. Outcomes from this study could help increase the number of colonies on a large scale, allowing for their use both ecologically and economically, and contribute to conservation efforts in native species of stingless bees.

Observations on the bionomics of the sheep body louse (Damalinia ovisM)

1952 ◽  
Vol 3 (1) ◽  
pp. 60 ◽  
Author(s):  
MT Scott
Keyword(s):  
Life Cycle ◽  
Relative Humidity ◽  
Incubation Period ◽  
Seasonal Fluctuation ◽  
Optimal Conditions ◽  
Body Louse ◽  
Poor Condition ◽  
Preoviposition Period ◽  
Cent Relative Humidity

Experimental observations are recorded on the bionomics of Damalinia ovis on the sheep and in vitro. The optimal conditions for in-vitro rearing of D. ovis are 36.5°C. and 70-90 per cent, relative humidity when a mixture of skin scurf and baker's yeast is used as food. Under these conditions the life cycle closely approximates the estimated life cycle on the sheep. The incubation period is 9-10 days; the three nymphal instars are completed in 7, 5, and 9 days respectively; the preoviposition period is approximately 3 days, making a cycle of 34 days from egg to egg. The lice and their eggs are very susceptible to changes in temperature. The areas of heaviest infestation are along the mid-dorsal line and down the sides of the sheep. Individual sheep differ considerably in their susceptibility to artificial and to natural infestations. Sheep in poor condition tend to have the heaviest infestations, which are retained throughout the year. There is a pronounced seasonal fluctuation in populations of D. ovis, the heaviest infestation occurring in the period from June to September.

Effect of Temperature on ADP-Induced Platelet Aggregation

1973 ◽  
Vol 29 (01) ◽  
pp. 183-189
Author(s):  
C. A Praga ◽  
E. M Pogliani
Keyword(s):  
Platelet Aggregation ◽  
Incubation Period ◽  
Room Temperature ◽  
Important Variable ◽  
Practical Significance ◽  
Effect Of Temperature ◽  
Induce Platelet Aggregation ◽  
Cuvette Holder ◽  
Exact Temperature

SummaryTemperature represents a very important variable in ADP-induced platelet aggregation.When low doses of ADP ( < 1 (μM) are used to induce platelet aggregation, the length of the incubation period of PRP in the cuvette holder of the aggregometer, thermostatted at 37° C, is very critical. Samples of the same PRP previously kept at room temperature, were incubated for increasing periods of time in the cuvette of the aggregometer before adding ADP, and a significant decrease of aggregation, proportional to the length of incubation, was observed. Stirring of the PRP during the incubation period made these changes more evident.To measure the exact temperature of the PRP during incubation in the aggre- gometer, a thermocouple device was used. While the temperature of the cuvette holder was stable at 37° C, the PRP temperature itself increased exponentially, taking about ten minutes from the beginning of the incubation to reach the value of 37° C. The above results have a practical significance in the reproducibility of the platelet aggregation test in vitro and acquire particular value when the effect of inhibitors of ADP induced platelet aggregation is studied.Experiments carried out with three anti-aggregating agents (acetyl salicyclic acid, dipyridamole and metergoline) have shown that the incubation conditions which influence both the effect of the drugs on platelets and the ADP breakdown in plasma must be strictly controlled.

CORTICOSTEROID-UMSATZ UND CORTICOSTEROID-PRODUKTION BEI RATTEN UNTER DER BEHANDLUNG MIT ANABOLEN STEROIDEN

1965 ◽  
Vol 48 (2) ◽  
pp. 263-271 ◽  
Author(s):  
Herbert Schriefers ◽  
Gerlinde Scharlau ◽  
Franzis Pohl
Keyword(s):  
Production Rate ◽  
Adult Female ◽  
Anabolic Steroids ◽  
Reduction Rate ◽  
Female Rats ◽  
Adrenal Weight ◽  
Hydrogenase Activity ◽  
Anabolic Effect ◽  
Liver Slices

ABSTRACT After the administration of anabolic steroids to adult female rats in daily doses of 1 mg per animal for 14 days, the following parameters were investigated: the rate of the Δ4-5α-hydrogenase-catalyzed cortisone reduction in liver slices and microsomal fractions, the adrenal weight and the in vitro corticosterone production rate. Among the steroids tested, only 17α-methyl-testosterone and 17α-ethyl-19-nor-testosterone were effective in lowering significantly cortisone reduction rate by liver slices with concomitant decreases in microsomal Δ4-5α-hydrogenase-activity. Testosterone, 19-nor-testosterone, 17α-ethinyl-19-nor-testosterone, 17α-methyl-17β-hydroxy-androsta-1,4-dien-3-one and 1-methyl-17β-hydroxy-androst-1-en-3-one were ineffective or only slightly effective. Adrenal weight and absolute corticosterone production rate (μg/60 min per animal) were decreased after treatment with 17α-methyl-testosterone, 17α-ethyl-19-nor-testosterone and 1-methyl-17β-hydroxy-androst-1-en-3-one. Corticosterone production was decreased with 17α-ethinyl-19-nor-testosterone in spite of an unchanged adrenal weight. The relative corticosterone production rate (μg/60 min · 100 mg adrenal) was in any cases unaffected. According to these results there exists – with the exception of 17α-ethinyl-19-nor-testosterone – a strict parallelism between corticosteroid turnover and corticosterone production rate: unchanged turnover is correlated with unchanged corticosterone production rate, while a decreased turnover is correlated with decreased adrenal activity. The protein-anabolic effect of certain anabolic steroids may be partly due to an anti-catabolic action of these compounds resulting from a decreased corticosteroid inactivation and production rate. Possible mechanisms by which anabolic steroids may affect corticosteroid-balance are discussed.

2002 Congress on In Vitro Biology

2002 ◽  
Author(s):  
John W. Harbell
Keyword(s):  
Vitro Biology

The Potential Migrated Mechanism of Water-Soluble Components in Pellets Prepared by Wet Extrusion/Spheronization: Effect of Drying Rate

2020 ◽  
Vol 17 ◽  
Author(s):  
Bingwei Wang ◽  
Jianping Liu ◽  
Zhenghua Li ◽  
Yulong Xia ◽  
Shuangshuang Zhang ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Water Soluble ◽  
In Vitro Dissolution ◽  
Drying Rate ◽  
Scanning Calorimetry ◽  
Drying Temperature ◽  
Wet Extrusion ◽  
Extrusion Spheronization ◽  
Soluble Components

Background: At present, there were numerous researches on the migration of components in tablets and granules, the investigation in the pharmaceutical literatrue concerning the effect of drying rate on the migration of water-soluble components of pellets was limited. Temperature and relative humidity (RH) were crucial parameters during the drying process which was an essential step in the preparation of pellets via wet extrusion/spheronization. To quantify these variables, the water loss percentage of pellets per minute was defined as drying rate. Objective: The study aimed to investigate the influence of drying rate on the migration of water-soluble components in wet pellets and the potential migrated mechanism. Methods: The pellets containing tartrazine as a water-soluble model drug and microcrystalline cellulose as a matrix former were prepared by extrusion/spheronization and dried at four different drying temperature and relative humidity. Afterward, the extent of migrated tartrazine was assessed regarding appearance, in-vitro dissolution test, Differential Scanning Calorimetry, X-Ray Powder Diffraction, Attenuated total reflectance Fourier transform infrared spectroscopy and Confocal Raman Mapping. Results: Results demonstrated that red spots of tartrazine appeared on the surface of pellets and more than 40% tartrazine were burst released within 5 minutes when pellets dried at 60℃/RH 10%. While pellets dried at 40℃/RH 80%, none of these aforementioned phenomena was observed. Conclusion: In conclusion, the faster drying rate was, the more tartrazine migrated to the exterior of pellets. Adjusting drying temperature and relative humidity appropriately could inhibit the migration of water-soluble components within wet extrusion/spheronization pellets.

Case study in 21 st century ecotoxicology: using in vitro aromatase inhibition data to predict short term in vivo responses in adult female fish

2020 ◽  
Author(s):  
Daniel L. Villeneuve ◽  
Brett R. Blackwell ◽  
Jenna E. Cavallin ◽  
Wan‐Yun Cheng ◽  
David J. Feifarek ◽  
...  
Keyword(s):  
Adult Female ◽  
Female Fish ◽  
Aromatase Inhibition ◽  
Short Term ◽  
Inhibition Data

scholarly journals Two Ecdysteroids Isolated from Micropropagated Lychnis flos-cuculi and the Biological Activity of Plant Material

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 904
Author(s):  
Michał P. Maliński ◽  
Jaromir Budzianowski ◽  
Małgorzata Kikowska ◽  
Monika Derda ◽  
Marcelina M. Jaworska ◽  
...  
Keyword(s):  
Biological Activity ◽  
Acute Toxicity ◽  
Plant Material ◽  
Present Report ◽  
Root Extract ◽  
Methanolic Extracts ◽  
Comparable Activity ◽  
Antiamoebic Activity ◽  
Amoebicidal Activity

Genetically uniform plant material, derived from Lychnis flos-cuculi propagated in vitro, was used for the isolation of 20-hydroxyecdysone and polypodine B and subjected to an evaluation of the antifungal and antiamoebic activity. The activity of 80% aqueous methanolic extracts, their fractions, and isolated ecdysteroids were studied against pathogenic Acanthamoeba castellani. Additionally, a Microtox® acute toxicity assay was performed. It was found that an 80% methanolic fraction of root extract exerts the most potent amoebicidal activity at IC50 of 0.06 mg/mL at the 3rd day of treatment. Both ecdysteroids show comparable activity at IC50 of 0.07 mg/mL. The acute toxicity of 80% fractions at similar concentrations is significantly higher than that of 40% fractions. Crude extracts exhibited moderate antifungal activity, with a minimum inhibitory concentration (MIC) within the range of 1.25–2.5 mg/mL. To the best of our knowledge, the present report is the first to show the biological activity of L. flos-cuculi in terms of the antifungal and antiamoebic activities and acute toxicity. It is also the first isolation of the main ecdysteroids from L. flos-cuculi micropropagated, ecdysteroid-rich plant material.

In-vivo and in-vitro secretion of prolactin by lactating rat adenohypophyses as a function of intracellular age

1984 ◽  
Vol 101 (1) ◽  
pp. 27-32 ◽  
Author(s):  
F. Mena ◽  
G. Martínez-Escalera ◽  
C. Clapp ◽  
C. E. Grosvenor
Keyword(s):  
Pituitary Gland ◽  
Incubation Period ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Polyacrylamide Gel ◽  
Pituitary Glands ◽  
H 26

ABSTRACT Adenohypophysial prolactin of lactating rats was pulse-labelled by [3H]leucine injected i.v. at the time of removal of the pups. The [3H]prolactin concentration in the pituitary gland, analysed by polyacrylamide-gel electrophoresis, progressively fell as the time from labelling to removal of the pituitary gland increased from 8 to 24 h, which suggests that there was a loss of hormone as it aged within the gland. Suckling effectively provoked the depletion–transformation of total and [3H]prolactin (extracted at pH 7·2) when applied after 8 h but not when applied after either 16 or 24 h after removing the pups. In rats whose pups were removed for 8 h, suckling also depleted–transformed [3H]prolactin labelled 4 h, but not that labelled 1 h before suckling. The pituitary glands of other lactating rats were labelled with [3H]leucine injected i.v. at various times before removing the glands and incubating them in medium 199. The secretion into the medium of [3H]prolactin labelled either 4, 8, 16 or 24 h beforehand was maximal during the first 30 min then declined from 30 to 240 min of incubation. However, secretion of prolactin labelled 1 h and 10 min beforehand reached a maximum after 0·5–1 h and 2 h of incubation respectively, then remained constant during the remainder of the 4-h incubation period. The total 4-h secretion of [3H]prolactin was greatest (65% of preincubation concentration) from those glands labelled 4 h before in contrast to those labelled 10 min (15%) or 1 (38%), 8 (34%), 16 (18%) or 24 h (26%) before incubation. Taken together, these data suggest that prolactin synthesized 4 h earlier is more likely to be released in response to physiological stimuli than is more recently formed prolactin or prolactin which has remained in the pituitary gland for 16 h or longer. J. Endocr. (1984) 101, 27–32

METABOLISM OF 20β-HYDROXY-4-PREGNEN-3-ONE IN UTERINE TISSUE OF NON-PREGNANT RATS IN VITRO

1976 ◽  
Vol 83 (3) ◽  
pp. 604-620 ◽  
Author(s):  
B. P. Lisboa ◽  
M. Holtermann
Keyword(s):  
Biological Activity ◽  
Adult Female ◽  
Female Rats ◽  
Uterine Tissue ◽  
Rat Uterus ◽  
Adult Rats ◽  
Pregnant Rats ◽  
Progesterone Metabolites ◽  
Ovariectomized Adult Rats

ABSTRACT In vitro experiments carried out with uterus preparations of ovariectomized adult rats indicate the presence in this tissue of a 20β-hydroxysteroid-oxidoreductase which catalyzes the conversion of 20β-hydroxy-4-pregnen-3-one to progesterone. Since a hepatic 20β-hydroxysteroid-oxidoreductase is absent in adult female rats, the myometrial enzyme can be responsible for the biological activity of 20β-hydroxy-4-pregnen-3-one in these animals. Besides progesterone five metabolites were isolated and identified after incubation of [4-14C]20β-hydroxy-4-pregnen-3-one with uterine tissue: 20β-hydroxy-5α-pregnan-3-one, 20β-hydroxy-5β-pregnan-3-one, 5α-pregnane-3α,20β-diol, 4-pregnene-3α,20β-diol and 4-pregnene-3β,20β-diol. The conversion of 20β-hydroxy-4-pregnen-3-one to progesterone permits us to regard all five steroids isolated as progesterone metabolites in the rat uterus. 20β-hydroxy-5β-pregnan-3-one is the first C21-metabolite with a 5β(H)-configuration isolated in the rat uterus, which indicates the presence of 5β-reductase in this tissue.

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