scholarly journals The effectiveness of glass beads for plating cell cultures

2018 ◽  
Author(s):  
Alidivinas Prusokas ◽  
Michelle Hawkins ◽  
Conrad A. Nieduszynski ◽  
Renata Retkute
Keyword(s):  
Petri Dish ◽  
Colony Growth ◽  
Glass Beads ◽  
Growth Media ◽  
Laboratory Procedure ◽  
Multiple Parameters ◽  
Liquid Suspension ◽  
The Mean ◽  
Common Laboratory ◽  
Cell Plating

AbstractCell plating, the spreading out of a liquid suspension of cells on a surface followed by colony growth, is a common laboratory procedure in microbiology. Despite this, the exact impact of its parameters on colony growth has not been extensively studied. A common protocol involves the shaking of glass beads within a petri dish containing solid growth media. We investigated the effects of multiple parameters in this protocol - the number of beads, the shape of movement, and the number of movements. Standard suspensions ofEscherichia coliwere spread while varying these parameters to assess their impact on colony growth. Results were compared by a number of metrics - the number of colonies, the mean distance between closest colonies, and the variability and uniformity of their spatial distribution. Finally, we devised a mathematical model of shifting billiard to explain the heterogeneities in the observed spatial patterns. Exploring the parameters that affect the most fundamental techniques in microbiology allows us to better understand their function, giving us the ability to precisely control their outputs for our exact needs.

scholarly journals CLINICAL FEATURES OF NOVEL CORONAVIRUS 2019-INFECTED CASES WITH PRE-EXISTING CARDIOVASCULAR DISEASE, DISAGGREGATED BY GENDER

2021 ◽  
Vol 54 (2) ◽  
pp. 180-185
Author(s):  
Elham Mohammadyari ◽  
Mohammad Reza Kaffashian ◽  
Iraj Ahmadi ◽  
Azra Kenarkoohi ◽  
Askar Soufinia ◽  
...  
Keyword(s):  
Clinical Features ◽  
Clinical Laboratory ◽  
Renin Angiotensin System ◽  
Angiotensin System ◽  
Men And Women ◽  
Blood Pressures ◽  
Males And Females ◽  
The Mean ◽  
Novel Coronavirus ◽  
Common Laboratory

Objectives: This study was conducted to evaluate the clinical features of 68 coronavirus 2019-infected cardiac cases on gender basis. Methodology: Clinical, laboratory and electrocardiographic data of 68 COVID-19 patients with pre-existing cardiovascular diseases, analyzed and compared by gender-wise. Results: Dry cough (78% of male, 80% females) and fever (62% of male, 75% females) were the most common symptoms. Out of these 97% of them needed O2 supplementation. O2 saturation in patients with O2 therapy was 85%; 31% of men and 11% of women experienced intubation. The most common laboratory abnormalities, were neutrophilia, leukocytosis, lymphopenia, thrombocytopenia, decreased hemoglobin level, increased creatinine and urea, in men and women. Troponin level was different between male and female. Pneumonia was found in 86-87% patients. Approximately, Males and female, respectively53.10 and 52.8%, shown sinus tachycardia (ST arrythmia). PVC arrythmia was found in 2.9% of total patients. BBB arrythmia was found in 31.20% of males vs. 11.10% of females. The mean systole/diastole blood pressures respectively were 130±4/79.7 ±2 in males and 134±4/81±3 in females. Heart axis changes was identified in 43.8% and 27.8% of males and females respectively. Conclusion: Severity of symptoms and outcomes of COVID-19 in cardiac patients showed some differences between men and women which could be associated with differences in immune responses, respiratory tract properties, renin angiotensin system, sex hormones and lifestyle.  However, more studies to categorize gender differences are required.

Acute infectious purpura fulminans: a case series from India

2020 ◽  
Vol 50 (4) ◽  
pp. 330-334
Author(s):  
Sumayya Abdul Kalam ◽  
Ronald AB Carey ◽  
John Antony ◽  
OC Abraham
Keyword(s):  
Clinical Symptoms ◽  
Spotted Fever ◽  
Purpura Fulminans ◽  
Case Series ◽  
Latex Agglutination ◽  
Elevated Alkaline Phosphatase ◽  
The Mean ◽  
Polymerase Chain ◽  
Common Laboratory ◽  
Overall Mortality

Acute infectious purpura fulminans is a serious, potentially fatal condition. We present a case series of 11 patients from March 2005 to March 2017, whose clinical symptoms were fever (100%), confusion (63.6%) and headache (55%), and whose common laboratory abnormalities were thrombocytopenia (100%), elevated alkaline phosphatase (70%) and anaemia (63.6%). Three patients (27%) developed gangrene and two presented in shock. Only one grew Neisseria meningitidis in cerebrospinal fluid (CSF) culture and another confirmed by latex agglutination and polymerase chain reaction in CSF. Five others had serology confirmed spotted fever rickettsioses (SFG). All received broad spectrum antibiotics; in 9/11 patients, this included doxycycline or azithromycin. The mean hospital stay was 10.2 days and overall mortality was 18.2%.

scholarly journals Sensitivity of Mycosphaerella fijiensis, Causal Agent of Black Sigatoka of Banana, to Propiconazole

1997 ◽  
Vol 87 (1) ◽  
pp. 96-100 ◽  
Author(s):  
R. A. Romero ◽  
T. B. Sutton
Keyword(s):  
Colony Growth ◽  
Significant Shift ◽  
Mycosphaerella Fijiensis ◽  
Black Sigatoka ◽  
Frequency Distributions ◽  
Natural Logarithm ◽  
History Of ◽  
The Mean ◽  
San Carlos ◽  
Relative Inhibition

One hundred monoascosporic isolates of Mycosphaerella fijiensis were collected in February and November 1994 from each of two banana (Musa spp.) plantations in Costa Rica. Locations at San Pablo and Coopecariari had been sprayed with propiconazole for the past 7 years to control black Sigatoka. One hundred monoascosporic isolates from a third location, San Carlos, with no history of fungicide use, also were tested for sensitivity to propiconazole. Fifty percent effective concentration (EC50) values were calculated for individual isolates by regressing the relative inhibition of colony growth against the natural logarithm of the fungicide concentration. In the February sample, the mean EC50 values for San Pablo and Coopecariari populations were 0.06 and 0.05 μg a.i. ml-1, respectively, which were not statistically different (P = 0.05). The mean EC50 value of the population at San Carlos was 0.008 μg a.i. ml-1, which was significantly lower (P = 0.001) than the mean EC50 values obtained at San Pablo and Coopecariari. Frequency distributions of EC50 values of isolates from the three populations collected in February showed that 80% of isolates from San Pablo and Coopecariari had EC50 values greater than the highest EC50 value from San Carlos, indicating a significant shift in reduced sensitivity to propiconazole. Isolates collected in November 1994, after eight treatments of propiconazole at San Pablo and Coopecariari, showed a significant increase in mean EC50 values compared with the means observed in February. The high proportion of isolates with reduced sensitivity to propiconazole may account for the unsatisfactory control of black Sigatoka between 1992 and 1993 in the two banana plantations at San Pablo and Coopecariari.

scholarly journals Studies on lolium multiflorum endosperm in tissue culture I. Nutrition

1973 ◽  
Vol 26 (1) ◽  
pp. 123 ◽  
Author(s):  
M MeryI Smith ◽  
BA Stone
Keyword(s):  
Tissue Culture ◽  
Suspension Culture ◽  
Doubling Time ◽  
Lolium Multiflorum ◽  
Carbon Sources ◽  
Equimolar Mixture ◽  
Liquid Suspension ◽  
The Mean ◽  
Liquid Suspension Culture

Stocks of L. multiflorum endosperm callus have been maintained in liquid suspension culture on a modified White's medium for 5 years. The mean doubling time under the conditions used is 3� 2 days. Best growth is obtained on sucrose; fructose and glucose are good carbon sources, whereas growth is only moderate on an equimolar mixture of both.

scholarly journals Clinical evaluation of point-of-care testing for wide-range C-reactive protein (wr-CRP) in neonates with suspected sepsis

2019 ◽  
Vol 43 (3) ◽  
pp. 135-140
Author(s):  
Amiel Billetop ◽  
Kerry Grant ◽  
Jennifer Beasmore ◽  
Francesca Mills ◽  
David Odd ◽  
...  
Keyword(s):  
Operating Characteristic ◽  
Point Of Care ◽  
Attractive Alternative ◽  
C Reactive Protein ◽  
Suspected Sepsis ◽  
Reactive Protein ◽  
Point Of Care Test ◽  
Wide Range ◽  
The Mean ◽  
Common Laboratory

Abstract Background The aim of this study was to validate a point-of-care C-reactive protein (CRP) test (QuikRead, wide-range [wr] CRP) against standard laboratory testing in neonates with suspected sepsis. Methods This was a single-centre prospective cohort study of neonates (n = 91). The main outcome measure was the paired evaluation of the wr-CRP point-of-care test and automated laboratory CRP tests in neonates with suspected sepsis. Results There were 126 measured CRP-sample pairs. The mean difference between the laboratory CRP and the wr-CRP point-of-care test values was 0.19 (95% confidence interval [CI]:‒1.0–0.65). Pearson’s correlation coefficient was 0.94. The area under the receiver operating characteristic (ROC) curve was 0.99 (95% CI: 0.98–1.00). At a QuikRead CRP cut-off of ≥6.2, the sensitivity and specificity were 77% and 100%, respectively. Conclusions Point-of-care wr-CRP testing can be used as a screening test in neonates with suspected sepsis. Rapid bed-side diagnostics and minimal blood volume requirements present an attractive alternative to common laboratory CRP testing.

On the influence of centrifugal buoyancy on rotating convection

2000 ◽  
Vol 403 ◽  
pp. 133-151 ◽  
Author(s):  
J. E. HART
Keyword(s):  
Thermal Stratification ◽  
Direct Action ◽  
Finite Amplitude ◽  
Heat Fluxes ◽  
Vertical Shear ◽  
Weakly Nonlinear ◽  
Rotating Convection ◽  
Physical Effects ◽  
The Mean ◽  
Common Laboratory

Centrifugal buoyancy forces in a container rotating about an axis aligned with gravity lead to mean flows that interact with rotating convection. A model of the interactions between these flows and the thermal instabilities that occur in weakly nonlinear rapidly rotating convection is used to estimate when, in terms of external parameters, centrifugal buoyancy has a substantial influence on thermal convective instability. The significant physical effects include the direct action of centrifugal buoyancy on the eddies themselves, the upwards advection of basic-state vertical shear by the perturbation rolls, and the alteration of the mean thermal stratification upon which eddies grow by the basic centrifugally induced circulation. It is shown that the first effect is the most important for common laboratory settings, and can lead to destabilization of the system at outer radii. Other manifestations of centrifugal buoyancy include the generation of a positive offset of the mean temperature at the centre of the cell, and a reduction of this offset by heat fluxes arising from the centrifugally modified finite-amplitude convective eddies.

scholarly journals Investigating Anti-mutagenic Activities of Lantana camara L. (Verbenaceae) Applying Salmonella typhimurium and the Ames Test

2020 ◽  
Vol 5 (3) ◽  
pp. 90-95
Author(s):  
Zahra Zare
Keyword(s):  
Salmonella Typhimurium ◽  
Ames Test ◽  
Petri Dish ◽  
Botanical Garden ◽  
Positive Control ◽  
Test Methods ◽  
Leaf Extracts ◽  
Percolation Method ◽  
Methanolic Extracts ◽  
The Mean

Introduction: Genetic mutations have a significant role in causing cancers, and plants are effective on cancer recovery by producing metabolites. In this regard, the present study aimed to evaluate the Lantana camera anti-mutation effects applying Salmonella typhimurium in the Ames test. Methods: To this end, the plant was prepared from the Iran National Botanical Garden in 2018 (Tehran, Iran), and the methanolic extracts of its leaves and flowers were obtained by the percolation method. Then, anti-mutagenic activities were studied by the Ames method and the assessment of the rate of reverse mutations in mutant Salmonella typhimurium. Mutant strains cannot grow on minimal mineral media thus only those bacteria that have acquired a wild genotype after reverse mutation in the presence of the mutagen are able to grow on this medium. The plant extract, along with a mutagen substance was used to evaluate its anti-mutagenic effects by counting grown colonies and calculating the mean mutation inhibitory index according to the "Ong" formula. Finally, anti-mutagenic activities were retested by adding the sterile extract of the mouse liver (S9), and the data were analyzed by SPSS statistical software, version 22.Results: In general, the results showed that the mean number of grown colonies decreased significantly despite the plant material in comparison with the standard. According to the "Ong" formula, the percentage of inhibition was [1-T/M]×100. Based on the results, T grew a number of colonies on each petri dish despite the mutagen and extract, and M grew a number of colonies in positive control plates. Eventually, mutation inhibition percentages in leaf extracts were significantly higher than those of flower extracts, which were 75.59 ± 0.73 (+S9) and 84.79 ± 0.17 (-S9), as well as 49.57 ± 0.55 (+S9) and 62.32 ± 0.23 (-S9), respectively (P < 0.05). Conclusion: In general, the leaves and flowers of L. camara demonstrated anti-mutagenic activities with higher activities in the leaves compared to flowers.

scholarly journals Platelet Size in Thrombocytopenias and Thrombocytosis of Various Origin

Blood ◽  
1973 ◽  
Vol 41 (4) ◽  
pp. 587-598 ◽  
Author(s):  
M. Kraytman
Keyword(s):  
Mitomycin C ◽  
Blood Platelets ◽  
Normal Population ◽  
Glass Beads ◽  
Reactive Thrombocytosis ◽  
Intravenous Injections ◽  
Platelet Size ◽  
The Mean ◽  
Morphologic Changes

Abstract Planimetric studies were carried out on canine blood platelets fixed with formaldehyde. In the normal dog, the mean platelet area was 5.25 sqµ (SEM ± 0.34 sqµ). During the first 3 days following acute experimental thrombocytopenia, platelet area increased, averaging 9.5 sqµ (p < 0.01). The reactive thrombocytosis following splenectomy or nephrectomy was not accompanied by a rise in large platelets. Platelet size decreased to 3.9 sqµ in dogs made thrombocytopenic by intravenous injections of mitomycin C. The morphologic changes induced by the various experimental procedures suggest that: (1) newly formed platelets are larger than platelets of a normal population; (2) some large platelets are possibly released by macromegakaryocytes; (3) other large thrombocytes probably represent fragments of granular megakaryocytes; (4) senescence of platelets in the circulation is associated with decreasing size; and (5) large young platelets are preferentially retained in vivo on glass beads.

scholarly journals Serial In Vitro Bone Marrow Culture in Acute Lymphocytic Leukemia

Blood ◽  
1973 ◽  
Vol 42 (5) ◽  
pp. 687-699 ◽  
Author(s):  
M. J. Duttera ◽  
J. M. Bull ◽  
J. D. Northup ◽  
E. S. Henderson ◽  
E. D. Stashick ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Acute Lymphocytic Leukemia ◽  
Colony Growth ◽  
Lymphocytic Leukemia ◽  
Leukemic Cells ◽  
Mean Values ◽  
Bone Marrow Cultures ◽  
The Mean ◽  
Nonlinear Fashion

Abstract Serial in vitro bone marrow cultures have been done on eight patients with acute lymphocytic leukemia. Colony-forming activity shows a rapid recovery from low values into the normal range in all patients who achieved stable remissions. Mean values for the stimulated cultures remained stable throughout consolidation, whereas the mean values for the unstimulated cultures declined during the same period. Relapse in two patients was preceded or accompanied by a concomitant decline in colony growth. Colony forming activity appears to be inhibited in a nonlinear fashion by increasing numbers of leukemic cells.

Differences in human and sheep platelet adherence, aggregation and activation induced by glass beads in a modified chandler loop-system

2021 ◽  
pp. 1-8
Author(s):  
G. Greif ◽  
C. Mrowietz ◽  
H. Meyer-Sievers ◽  
M. Ganter ◽  
F. Jung ◽  
...  
Keyword(s):  
Platelet Count ◽  
Mean Platelet Volume ◽  
Human Platelets ◽  
Glass Beads ◽  
Loop System ◽  
Platelet Volume ◽  
Activation Markers ◽  
Chandler Loop ◽  
Silicon Tube ◽  
The Mean

In human cardiovascular research, sheep in particular are used as a large animal model in addition to pigs. In these animals, medical products, developed and tested for human medical purposes, are almost exclusively used in interventional studies. Therefore, the extent to which platelets from human and ovine blood differ in terms of adherence, aggregation and activation after a 4- or 8-minutes exposure to glass was investigated. Testing was performed with platelet-rich plasma (PRP) and a modified Chandler loop system, with 4- and 8-minute blood-material exposure times corresponding to 20 and 40 test cycles, respectively, through the entire silicon tube loop of the test system. In sheep and human PRP, contact with the silicone tubing resulted in a decrease in platelet count after 4 minutes and 20 test cycles, respectively. Four more minutes (20 additional test cycles) caused a further decrease of the platelet count only in sheep PRP. When the silicon tube was partly filled with glass beads, these effects were more pronounced and stronger in sheep then in human PRP. The mean platelet volume, which was used as parameter for platelet aggregation, did not change over time in human PRP without glass exposure. With glass exposure in human and sheep PRP the mean platelet volume increased within 40 test cycles, but this increase was stronger in sheep than in human PRP. Regarding activation behavior, the activation markers CD62P and CD63 were detectable only in < 30% (sheep) and < 45% (human) of platelets, whereas after 8 min of glass exposure, the proportion of CD62P+ and CD63+ cells was more increased than before only in sheep. These results indicate that ovine platelets adhere more strongly to glass and show stronger aggregation behavior after glass contact than human platelets, but that ovine and human platelets differ only slightly in activability by glass.

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