scholarly journals THE INFLUENCE THAT SERUM EXERTS UPON TRYPANOSOMES, WITH SPECIAL REFERENCE TO ITS USE FOR EXPERIMENTS IN VITRO WITH ATOXYL AND PARAMINO-PHENYLARSENOXYD

1915 ◽  
Vol 21 (3) ◽  
pp. 250-257 ◽  
Author(s):  
B. T. Terry
Keyword(s):  
Special Reference ◽  
Salt Solution ◽  
Room Temperature ◽  
Toxic Substance ◽  
Normal Morphology ◽  
Undiluted Serum ◽  
Cattle Serum ◽  
Better Than

1. Serum of various animals preserves the motility of nagana trypanosomes better and longer than salt solution. 2. To act best in this way the serum should not be diluted more than 2 to 4 times. Undiluted serum is perhaps best. 3. Serum filtered through a Berkefeld filter, bottled aseptically, and kept in the ice box preserves this activating property apparently undiminished for many months. 4. Serum preserves the motility of trypanosomes better than "Sals physiologicum" of Merck, and better than the Ringer solutions of Meltzer and Carrel. 5. Serum preserves the normal morphology of trypanosomes better than the Ringer solutions tested. 6. The infectiousness of trypanosomes suspended in cattle serum was preserved at room temperature for at least 8 days. 7. The vitality of the trypanosomes in serum was seemingly better preserved at room temperature than at ice box temperature. 8. Serum incubated with atoxyl does not transform it into a toxic substance. 9. Serum does not bind paraminophenylarsenoxyd, for trypanosomes suspended in serum are often immobilized more quickly by paraminophenylarsenoxyd than trypanosomes suspended in salt solution. 10. Serum is suitable for suspending trypanosomes for certain experiments in vitro, and with proper precautions may be employed for transporting virus from laboratory to laboratory.

Factors affecting the yield and biological activity of lipid extracts of Listeria monocytogenes

1969 ◽  
Vol 15 (5) ◽  
pp. 421-428 ◽  
Author(s):  
R. A. Tadayon ◽  
K. K. Carroll ◽  
R. G. E. Murray
Keyword(s):  
Biological Activity ◽  
Listeria Monocytogenes ◽  
Special Reference ◽  
Room Temperature ◽  
Blood Picture ◽  
Factors Affecting ◽  
Age And Sex ◽  
Better Than ◽  
Young Mice

The biological activity of lipid extracts of five strains of Listeria monocytogenes was studied, with special reference to their monocytosis-producing activity in mice. Two of the strains gave more active extracts than the others, and cells grown at 4 C produced more lipid with better activity than cells grown at room temperature or at 37 C. Extracts obtained from cells harvested at the various stages of log phase at 4 C all gave similar levels of monocytosis in mice. The level of monocyte response varied from animal to animal, but in general, older mice (28 to 48 weeks) responded better than young mice (9 to 15 weeks) and females gave a better response than males. These extracts also produced leucopenia in young mice, but this was less consistent and leucocytosis was more often observed in older mice. Granulocytosis and lymphopenia were commonly found in mice injected with lipid extracts of L. monocytogenes. These changes were affected by the strain of bacteria but not by the age and sex of the test animals. The changes in blood picture normally reached a maximum 1 to 2 days after injection and returned to normal after about 5 days.

scholarly journals Synthesis, Antibacterial, Thrombolytic and Cytotoxic Evaluation of Substituted and Un-substituted Selenium-n-heterocyclic Carbene Adducts

2022 ◽  
Author(s):  
Amna Kamal ◽  
Muhammad Adnan Iqbal ◽  
Haq Nawaz Bhatti ◽  
Abdul Ghaffar
Keyword(s):  
Antibacterial Activity ◽  
Bacillus Subtilis ◽  
Bacillus Cereus ◽  
Room Temperature ◽  
Inhibition Zone ◽  
Spectroscopic Techniques ◽  
Mouse Blood ◽  
Ft Ir ◽  
Better Than

Abstract N-heterocyclic carbene salts bearing alkyl substituents (1-8) and their selenium N-heterocyclic carbene adducts (9-12) were synthesized and characterized by elemental analysis, FT-IR, NMR (1HNMR, 13CNMR) spectroscopic techniques. All the adducts were found to be stable in air and moisture at room temperature. Compounds (5-12) were evaluated against Bacillus subtilis Macrococcus brunensis and Bacillus cereus in vitro. The biological assay revealed that antibacterial activity of Selenium-N-heterocyclic carbene adducts are comparatively better than the salts. MIC and inhibition zone values showed that Bacillus subtilis is more active to selenium adducts (9-12) than Macrococcus brunensis and Bacillus cereus whereas opposite in the salts (5-8). In vitro studies of hemolysis and thrombolysis demonstrated that the synthesized compounds are innocuous for pre-clinical trials to mouse blood.

scholarly journals Alteration in the Efficacy of in Vitro Vancomycin and Ceftazidime Prepared in Normal Saline Versus Balanced Salt Solution in the Management of Ocular Infections

2021 ◽  
pp. 326-331
Author(s):  
Hussain Ahmad Khaqan ◽  
Laraib Hassan ◽  
Sabah Eric ◽  
Hasnain Muhammad Buksh ◽  
Raheela Naz ◽  
...  
Keyword(s):  
Salt Solution ◽  
Normal Saline ◽  
Room Temperature ◽  
Relevant Literature ◽  
Review Article ◽  
Ocular Infections ◽  
The Media ◽  
Search Approach ◽  
Key Terms

Objective: The purpose of this review article is to highlight the efficacy of Vancomycin and Ceftazidime formulated in different solutions for ocular use in the management of microbiological Ocular infections varies. Methodology: To locate and assess all relevant literature, we employed systematic review as a search approach, utilizing punctilious and unambiguous methodologies. We initiated by stipulating key terms and selecting appropriate databases for your literature search. To find replicable and reportable publications from high-quality peer-reviewed journals, we used Google Scholar, PubMed, and Research Gate. Results: Ceftazidime precipitated at 37 degree Celsius, but not at room temperature, however it did not show any effect on the pH of the medium. In both the media of Normal Saline and Balanced Salt Solution, it precipitated on its own or when coupled with vancomycin. Ceftazidime was initially prepared in Balanced Salt Solution rather than Normal Saline, which resulted in further precipitation. Ceftazidime prepared in Normal Saline precipitated to 54% after 168 hours in the dialysis chambers, compared to 88% in Balanced Salt Solution. Ceftazidime synthesized in Normal Saline declined from an initial concentration of 137.5 to 73.4 µg/ml  after 48 hours, while ceftazidime prepared in Balanced Salt Solution decreased to 6.3µg/ml. Vancomycin precipitation was inappreciable. Conclusion: Vancomycin did not precipitate in Normal Saline or Balanced Salt Solution, according to this systemic study. Regardless of the presence of vancomycin, ceftazidime precipitated, and it precipitated more expeditiously if it was produced in Balanced Salt Solution rather than Normal Saline.

scholarly journals Cold-Stored Platelets to Reverse Dual Antiplatelet Therapy

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 525-525 ◽  
Author(s):  
Moritz Stolla ◽  
Anthony Vargas ◽  
Shawn Bailey ◽  
Lydia Fang ◽  
Esther Pellham ◽  
...  
Keyword(s):  
Arachidonic Acid ◽  
Antiplatelet Therapy ◽  
Room Temperature ◽  
Dual Antiplatelet Therapy ◽  
Bleeding Complications ◽  
Loading Dose ◽  
Flow Conditions ◽  
P2y12 Inhibitors ◽  
Better Than

Abstract Background: Dual antiplatelet therapy (DAPT) with acetylsalicylic acid (ASA, aspirin) and P2Y12 inhibitors has improved outcomes in patients with acute coronary syndrome. However, major bleeding complications have compromised the benefits of these drugs and there is currently no effective therapy for excessive bleeding or antidote before urgent surgery. Room temperature-stored platelet transfusions (RSP) can reverse the effect of ASA, however they are not effective at reversing the effects of P2Y12 inhibitors. Cold-stored platelets (CSP) were the standard of care in the 60s and 70s, but they were abandoned, when reduced survival was noted in radiolabeling studies. CSP may have several advantages over RSP in this setting including a state of pre-activation and therefore a potentially superior hemostatic function. For actively bleeding patients, requiring therapeutic transfusions, CSP may be the better product, but CSP have never been investigated for the reversal of DAPT. Methods/Results: Platelet responses to arachidonic acid and ADP, which are critical for the pathways inhibited by ASA and clopidogrel, were tested. We found that αIIbβ3 integrin activation, measured by the activation specific PAC-1 antibody by flow cytometry, is significantly better in platelets stored up to 15 days in the cold compared to platelets stored for 5 day at room temperature. Even 15 day cold-stored platelets treated with arachidonic acid gave a similar response to fresh platelets. Similarly, in dose response experiments using standard light transmission aggregometry we found significantly superior responses to arachidonic acid and ADP over a wide range of doses with 5 day CSP compared to 5 day RSP. The CSP response to arachidonic acid was very similar to freshly prepared platelets from low to high doses. To test in vitro reversal, we treated platelets with the in vitro P2Y12 inhibitor 2-MeSAMP which resulted in significantly reduced aggregation in response to ADP. When platelets stored for 5 days in the cold were added one minute prior to stimulation with 10 µM ADP, the aggregation response was similar to that observed after adding freshly isolated platelets and significantly better than with platelets stored for 5 days at room temperature. To test whether CSP are better than RSP in promoting adhesion and aggregation under flow conditions we performed flow chamber experiments. Chambers were coated with 400µg/ml collagen and perfused with arterial shear (1500 1/s) for 5min. We treated C57BL/6J mice with a loading dose of DAPT and labeled, DAPT inhibited, native mouse platelets with a commercially available, fluorescently labeled GPIb antibody ex vivo. Calcein-AM labeled human RSP or CSP were added to the labeled mouse whole blood and subsequently perfused. We found the mean fluorescence intensity to be significantly higher with CSP compared to RSP over time, highlighting a superior reversal effect under flow conditions. To test CSP and RSP for DAPT reversal in a mouse model, we treated NOD/SCID mice with a loading dose of DAPT. We cut 2mm of the distal tail and collected blood over 30 minutes, followed by hemoglobin concentration measurement in the collected fluid. Interestingly, retroorbital transfusion of human 5 day stored RSP, resulted in significantly more blood loss compared to the group without transfusion. CSP-transfused mice lost less blood than the RSP-transfused mice, but no significant difference was observed when CSP-transfused mice were compared to the group without transfusion. Conclusion: Our in vitro and in vivo data indicate that CSP could have a critical advantage over RSP when reversal of DAPT is required. Disclosures No relevant conflicts of interest to declare.

117 EFFECT OF STEPWISE DILUTION ON THE VIABILITY OF FROZEN - THAWED BOVINE OOCYTES MATURED IN VITRO

2007 ◽  
Vol 19 (1) ◽  
pp. 176 ◽  
Author(s):  
A. Hamawaki ◽  
S. Hamano ◽  
M. Yoshikawa ◽  
K. Matsukawa
Keyword(s):  
Bovine Serum ◽  
Room Temperature ◽  
Fetal Bovine Serum ◽  
Calf Serum ◽  
Fertilization Rate ◽  
Single Step ◽  
Normal Morphology ◽  
Fetal Bovine ◽  
Bovine Oocytes

The purpose of this study was to evaluate the effect of stepwise dilution on the viability of frozen–thawed bovine oocytes matured in vitro. Oocytes matured in vitro were denuded and equilibrated in modified TCM-199 (m199: 11 mmol L-1 HEPES, 9 mmol L-1 Na-HEPES, 5 mmol L-1 NaHCO3, 20% (v/v) calf serum) supplemented with 10% (v/v) glycerol for 15 min at room temperature (RT). Then they were exposed to m199 with 10% glycerol and 0.25 mol L-1 sucrose and loaded into 0.25-mL plastic straws. The straws were sealed and seeded at -6�C, cooled at the rate of 0.33�C min-1 to -25�C, and plunged into LN2. For thawing, the straws were first held in air at RT for 10 s, followed by immersion in 30�C water for 10 s. In the first experiment, frozen-thawed oocytes were subjected to cryoprotectants in 5 different manners of dilution. In the non-step dilution, the oocytes (n = 60) were put into m199 for 5 min. In the single-step dilution, the oocytes (n = 37) were transferred to 0.25 mol L-1 sucrose in m199 for 5 min. In the two-step dilution, the oocytes (n = 56) were transferred to 0.5 and then 0.25 mol L-1 sucrose in m199 for 5 and 5 min, respectively. In the three-step dilution, the oocytes (n = 57) were transferred to 0.75, 0.5, and 0.25 mol L-1 sucrose in m199 for 1, 5, and 5 min, respectively. In the four-step dilution, the oocytes (n = 52) were transferred to 1.0, 0.75, 0.5, and 0.25 mol L-1 sucrose in m199 for 1, 1, 5, and 5 min, respectively. After dilution, all of the oocytes were washed twice in TCM-199 supplemented with 5% fetal bovine serum for 5 min and cultured for 1 h to assess the morphology. The rate of morphological normal oocytes in the four-step dilution (94.2%) was significantly (P < 0.05) higher than that in other groups (non-, single-, two-, and three-step dilution: 61.7%, 73.0%, 78.6%, and 77.2%). In the second experiment, non-frozen (control, n = 170) and frozen–thawed oocytes (n = 145) with four-step dilution were fertilized and cultured in vitro (Kuwayama 1992 J. Reprod. Fert. 96, 187–193). To assess fertilization, some of the oocytes were fixed at 10 h after insemination. Cleavage and blastocyst rates were determined on Day 2 and Day 8 after fertilization (Day 0), respectively. There was no difference (P > 0.05) between control and frozen–thawed oocytes in the fertilization rate (88.0% vs. 93.1%). Some of the frozen–thawed oocytes cleaved and developed to blastocysts (44.0% and 11.2%), although the rates were significantly (P < 0.01) lower than those in control (71.7% and 35.0%). These results indicate that stepwise dilution of frozen–thawed oocytes improves the recovery of oocytes with normal morphology, and that the oocytes maintain the abilities to be fertilized and develop to blastocysts.

Hexamethyldisilazane: A modified procedure

1989 ◽  
Vol 47 ◽  
pp. 1006-1007
Author(s):  
Verdon Laliberté ◽  
L.L. Hayes ◽  
B.M. Stanulis-Praeger
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Uranyl Acetate ◽  
Cell Contact ◽  
Critical Importance ◽  
Drying Procedures ◽  
Critical Point Drying ◽  
Scanning Electron ◽  
Better Than

Scanning electron microscopy is a powerful tool in the study of cell contact in vitro, and has shown, specifically, that fibroblasts under conditions of growth restriction increase cell contact by filopodia. Accurate quantitation of surface features like filopodia, however, depends particularly upon artifact-free drying procedures. Critical point drying (CPD) of fibroblast monolayers all too often causes cell flattening, shrinkage, loss of surface detail and cracking (Fig. 1). Newer methods utilizing hexamethyldisilazane (HMDS) and uranyl acetate (UA) preserve fibroblast contour and surface architecture better than CPD, but solvent choice in the preparation of UA is of critical importance. UA in 70% ethanol results in the formation of precipitate (Fig. 2) whether the specimens are in the cold (4°C) or at room temperature, overnight or for periods less than 1 hour regardless of filtering. It occurs when incubation is carried out in the dark and when it is followed by copious rinses in 70% ethanol.

In Situ Localization of PPAR Gamma and Uncoupling Protein in Mouse Embryo Sections Using Digoxigenin-Labeled Riboprobes

1996 ◽  
Vol 54 ◽  
pp. 32-33
Author(s):  
C. Jennermann ◽  
S. A. Kliewer ◽  
D. C. Morris
Keyword(s):  
Alkaline Phosphatase ◽  
Room Temperature ◽  
Uncoupling Protein ◽  
Ppar Gamma ◽  
Nuclear Hormone Receptor ◽  
Full Length ◽  
Northern Analysis ◽  
Peroxisome Proliferator

Peroxisome proliferator-activated receptor gamma (PPARg) is a member of the nuclear hormone receptor superfamily and has been shown in vitro to regulate genes involved in lipid metabolism and adipocyte differentiation. By Northern analysis, we and other researchers have shown that expression of this receptor predominates in adipose tissue in adult mice, and appears first in whole-embryo mRNA at 13.5 days postconception. In situ hybridization was used to find out in which developing tissues PPARg is specifically expressed.Digoxigenin-labeled riboprobes were generated using the Genius™ 4 RNA Labeling Kit from Boehringer Mannheim. Full length PPAR gamma, obtained by PCR from mouse liver cDNA, was inserted into pBluescript SK and used as template for the transcription reaction. Probes of average size 200 base pairs were made by partial alkaline hydrolysis of the full length transcripts. The in situ hybridization assays were performed as described previously with some modifications. Frozen sections (10 μm thick) of day 18 mouse embryos were cut, fixed with 4% paraformaldehyde and acetylated with 0.25% acetic anhydride in 1.0M triethanolamine buffer. The sections were incubated for 2 hours at room temperature in pre-hybridization buffer, and were then hybridized with a probe concentration of 200μg per ml at 70° C, overnight in a humidified chamber. Following stringent washes in SSC buffers, the immunological detection steps were performed at room temperature. The alkaline phosphatase labeled, anti-digoxigenin antibody and detection buffers were purchased from Boehringer Mannheim. The sections were treated with a blocking buffer for one hour and incubated with antibody solution at a 1:5000 dilution for 2 hours, both at room temperature. Colored precipitate was formed by exposure to the alkaline phosphatase substrate nitrobluetetrazoliumchloride/ bromo-chloroindlylphosphate.

Evaluation of 99mTc-Label led Vitamin K4 as an Agent for Testicular Imaging

1991 ◽  
Vol 30 (01) ◽  
pp. 35-39 ◽  
Author(s):  
H. S. Durak ◽  
M. Kitapgi ◽  
B. E. Caner ◽  
R. Senekowitsch ◽  
M. T. Ercan
Keyword(s):  
Soft Tissue ◽  
Room Temperature ◽  
Normal Subjects ◽  
Left Testis ◽  
Wide Range ◽  
Activity Ratios ◽  
The Right ◽  
Radioactivity Levels

Vitamin K4 was labelled with 99mTc with an efficiency higher than 97%. The compound was stable up to 24 h at room temperature, and its biodistribution in NMRI mice indicated its in vivo stability. Blood radioactivity levels were high over a wide range. 10% of the injected activity remained in blood after 24 h. Excretion was mostly via kidneys. Only the liver and kidneys concentrated appreciable amounts of radioactivity. Testis/soft tissue ratios were 1.4 and 1.57 at 6 and 24 h, respectively. Testis/blood ratios were lower than 1. In vitro studies with mouse blood indicated that 33.9 ±9.6% of the radioactivity was associated with RBCs; it was washed out almost completely with saline. Protein binding was 28.7 ±6.3% as determined by TCA precipitation. Blood clearance of 99mTc-l<4 in normal subjects showed a slow decrease of radioactivity, reaching a plateau after 16 h at 20% of the injected activity. In scintigraphic images in men the testes could be well visualized. The right/left testis ratio was 1.08 ±0.13. Testis/soft tissue and testis/blood activity ratios were highest at 3 h. These ratios were higher than those obtained with pertechnetate at 20 min post injection.99mTc-l<4 appears to be a promising radiopharmaceutical for the scintigraphic visualization of testes.

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.

Human Platelet Acetylcholinesterase: The Effects of Anticholinesterases on Platelet Function

1979 ◽  
Vol 42 (05) ◽  
pp. 1615-1619 ◽  
Author(s):  
Martin J Smith ◽  
Boyd Braem ◽  
Kent D Davis
Keyword(s):  
Platelet Function ◽  
Ache Activity ◽  
Room Temperature ◽  
Platelet Rich Plasma ◽  
Complete Inhibition ◽  
Clot Retraction ◽  
Plasma Clot ◽  
Normal Platelet ◽  
Aggregation Factor

SummaryPlatelet acetylcholinesterase (AChE) activity was measured in gel-filtered platelet preparations. Three different anticholinesteratic agents (eserine, neostigmine, and diiso- propylphosphorofluoridate) at final concentrations of 10 μM caused complete inhibition of AChE activity after 30 min incubation at room temperature with either platelet-rich plasma or gel-filtered platelets. Complete inhibition of platelet AChE had no effect on platelet aggregation, factor-3 availability, and plasma clot retraction. We conclude that platelet membrane AChE activity is not required for normal platelet function as measured by these in vitro parameters.

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