Desiccation tolerance in mosses. I. Development of a method for measuring cell damage

1986 ◽  
Vol 64 (11) ◽  
pp. 2388-2392 ◽  
Author(s):  
V. J. Streusand ◽  
H. Ikuma
Keyword(s):  
Sample Size ◽  
Desiccation Tolerance ◽  
Cell Damage ◽  
Large Sample Size ◽  
Measuring Cell ◽  
Perfect Correlation ◽  
Before And After ◽  
Number Of Leaves ◽  
Number Of Cells

Preliminary studies indicated that samples of moss varied widely in cell damage both before and after desiccation and rehydration. In the present study, various parameters associated with cell damage in mosses were investigated. Determination of the percent cell damage in a particular sample of moss requires that (i) a large number of cells be counted throughout a given leaf and (ii) a large number of leaves and shoots be utilized. The use of large sample size is necessitated by large variance within leaves and among leaves and shoots of the same clump. In the present study a standardized method was developed which involves counting at least 10 cells in six areas of each leaf, six leaves on each shoot, and 10 shoots per treatment. Although the variance within samples is still high, this method was found to be effective for indexing desiccation damage, providing a near perfect correlation with shoot survival (r = 0.98).

The Plasmin Inhibitors of Plasma

1964 ◽  
Vol 12 (01) ◽  
pp. 119-125 ◽  
Author(s):  
Y Shamash ◽  
A Rimon
Keyword(s):  
Human Plasma ◽  
New Method ◽  
Normal Amount ◽  
Caseinolytic Activity ◽  
Before And After ◽  
Plasmin Inhibitors

SummaryA new method for the assay of plasmin inhibitors in human plasma is described. The method consists of determination of the caseinolytic activity of a standard plasmin solution before and after incubation with the inhibitor, with lysine added to the mixture as a stabilizer of plasmin. Using this method, it was found that plasma contains enough inhibitors to inactivate 30 caseinolytic units of plasmin, or 10 times the normal amount of plasminogen in human plasma.

FRACTIONAL DETERMINATIONS OF URINARY 17-KETOSTEROIDS IN HYPEREMESIS GRAVIDARUM

1962 ◽  
Vol 41 (1) ◽  
pp. 123-128 ◽  
Author(s):  
Pentti A. Järvinen ◽  
Sykkö Pesonen ◽  
Pirkko Väänänen
Keyword(s):  
Hyperemesis Gravidarum ◽  
First Trimester ◽  
Control Group ◽  
Before And After ◽  
Daily Urine ◽  
First Trimester Of Pregnancy ◽  
The Difference

ABSTRACT The fractional determination of 17-ketosteroids in the daily urine was performed in nine cases of hyperemesis gravidarum and in four control cases, in the first trimester of pregnancy both before and after corticotrophin administration. The excretion of total 17-KS is similar in the two groups. Only in the hyperemesis group does the excretion of total 17-KS increase significantly after corticotrophin administration. The fractional determination reveals no difference between the two groups of patients with regard to the values of the fractions U (unidentified 17-KS), A (androsterone) and Rest (11-oxygenated 17-KS). The excretion of dehydroepiandrosterone is significantly higher in the hyperemesis group than in the control group. The excretion of androstanolone seems to be lower in the hyperemesis group than in the control group, but the difference is not statistically significant. The differences in the correlation between dehydroepiandrosterone and androstanolone in the two groups is significant. The high excretion of dehydroepiandrosterone and low excretion of androstanolone in cases of hyperemesis gravidarum is a sign of adrenal dysfunction.

DETERMINATION OF BLOOD CORTICOIDS USING THE IN VITRO RESIN UPTAKE OF 3H-PREDNISOLONE

1968 ◽  
Vol 57 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Hironori Nakajima ◽  
Mitsunori Murala ◽  
Masumitsu Nakata ◽  
Takeshi Naruse ◽  
Seiji Kubo
Keyword(s):  
Thyroid Function Test ◽  
Normal Subjects ◽  
Adrenal Function ◽  
Function Test ◽  
Before And After ◽  
Adrenal Response ◽  
Suppression Test

ABSTRACT The in vitro resin uptake of 3H-prednisolone was used for the determination of blood cortisol after addition of radioactive prednisolone followed by Amberlite CG 400 Type 1 to the test serum, and incubation of the mixture. The radioactivity of the supernatant was compared before and after the addition of the resin. The principle of this method is similar to that of the 131I-triiodothyronine resin uptake for the thyroid function test. The tests for the specificity, reproducibility and sensitivity gave satisfactory results. The mean basal value ± SD of the 3H-prednisolone resin uptake was 35.3 ± 9.2% in normal subjects, and 27.1 ± 4.8% in pregnant women. This method was valid in various adrenal function tests, i. e. the adrenal circadian rhythm, corticotrophin (ACTH) test, dexamethasone suppression test and the adrenal response to lysine-8-vasopressin. It proved to be a sensitive indicator of the adrenal function. These results suggest that this method should be useful for a routine adrenal function test.

PENENTUAN KRITERIA PENILAIAN KESAN JUMLAH LEUKOSIT PADA PEMERIKSAAN APUSAN DARAH TEPI

2018 ◽  
Vol 3 (2) ◽  
pp. 52-61
Author(s):  
Dzikra Arwie ◽  
Islawati
Keyword(s):  
Data Analysis ◽  
Statistical Analysis ◽  
Blood Cells ◽  
Blood Smear ◽  
White Blood Cells ◽  
Peripheral Blood Smear ◽  
Field Of View ◽  
Laboratory Observation ◽  
Number Of Cells

Leukocytes or white blood cells have a characteristic characteristic of different cells. Determination of the impression of the number of leukocytes is determined in the number of cells in the field of view. While the number of viewable field cells expressed is still quite varied. The purpose of this study was to determine the number of leukocytes in the field of view and expressed the impression of a sufficient amount. This research was conducted at the Laboratory of Health Analyst Department Panrita Husada Bulukumba on 9 April 2017 to 14 July 2017. This type of research is a laboratory observation that aims to determine the criteria for assessing the impression of the number of leukocytes on a peripheral blood smear. Data analysis using statistical analysis is the average and standard deviations to determine the impression of the number of leukocytes and use 3 inspection zones. The results of this study obtained results in zone IV the number of leukocyte impressions said to be sufficient was 7-10, in zone V the number of leukocyte impressions said to be sufficient was 4-9, and in zone VI the number of leukocyte impressions said to be sufficient was 3-8.  

scholarly journals Feasibility of Race by Sex Intersectionality Research on Suicidality in the Adolescent Brain Cognitive Development (ABCD) Study

Children ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 437
Author(s):  
Shervin Assari ◽  
Shanika Boyce ◽  
Mohsen Bazargan
Keyword(s):  
Cognitive Development ◽  
Sample Size ◽  
Child Behavior Checklist ◽  
Reliability And Validity ◽  
Self Report ◽  
Large Sample Size ◽  
Cross Sectional ◽  
Cronbach Alpha ◽  
Rich Data ◽  
Suicidal Ideas

Intersectional research on childhood suicidality requires studies with a reliable and valid measure of suicidality, as well as a large sample size that shows some variability of suicidality across sex by race intersectional groups. Objectives: We aimed to investigate the feasibility of intersectionality research on childhood suicidality in the Adolescent Brain Cognitive Development (ABCD) study. We specifically explored the reliability and validity of the measure, sample size, and variability of suicidality across sex by race intersectional groups. Methods: We used cross-sectional data (wave 1) from the ABCD study, which sampled 9013 non-Hispanic white (NHW) or non-Hispanic black (NHB) children between the ages of 9 and 10 between years 2016 and 2018. Four intersectional groups were built based on race and sex: NHW males (n = 3554), NHW females (n = 3158), NHB males (n = 1164), and NHB females (n = 1137). Outcome measure was the count of suicidality symptoms, reflecting all positive history and symptoms of suicidal ideas, plans, and attempts. To validate our measure, we tested the correlation between our suicidality measure and depression and Child Behavior Checklist (CBCL) sub-scores. Cronbach alpha was calculated for reliability across each intersectional group. We also compared groups for suicidality. Results: We observed some suicidality history in observed 3.2% (n = 101) of NHW females, 4.9% (n = 175) of NHW males, 5.4% (n = 61) of NHB females, and 5.8% (n = 68) of NHB males. Our measure’s reliability was acceptable in all race by sex groups (Cronbach alpha higher than .70+ in all intersectional groups). Our measure was valid in all intersectional groups, documented by a positive correlation with depression and CBCL sub-scores. We could successfully model suicidality across sex by race groups, using multivariable models. Conclusion: Given the high sample size, reliability, and validity of the suicidality measure, variability of suicidality, it is feasible to investigate correlates of suicidality across race by sex intersections in the ABCD study. We also found evidence of higher suicidality in NHB than NHW children in the ABCD study. The ABCD rich data in domains of social context, self-report, schools, parenting, psychopathology, personality, and brain imaging provides a unique opportunity to study intersectional differences in neural circuits associated with youth suicidality.

Desiccation Tolerance: Avoiding Cellular Damage During Drying and Rehydration

2020 ◽  
Vol 71 (1) ◽  
pp. 435-460 ◽  
Author(s):  
Melvin J. Oliver ◽  
Jill M. Farrant ◽  
Henk W.M. Hilhorst ◽  
Sagadevan Mundree ◽  
Brett Williams ◽  
...  
Keyword(s):  
Desiccation Tolerance ◽  
Cell Damage ◽  
Cellular Responses ◽  
Land Plants ◽  
Cellular Damage ◽  
Cellular Protection ◽  
Vegetative Tissues ◽  
Tolerant Plants ◽  
Core Set ◽  
Protection Mechanisms

Desiccation of plants is often lethal but is tolerated by the majority of seeds and by vegetative tissues of only a small number of land plants. Desiccation tolerance is an ancient trait, lost from vegetative tissues following the appearance of tracheids but reappearing in several lineages when selection pressures favored its evolution. Cells of all desiccation-tolerant plants and seeds must possess a core set of mechanisms to protect them from desiccation- and rehydration-induced damage. This review explores how desiccation generates cell damage and how tolerant cells assuage the complex array of mechanical, structural, metabolic, and chemical stresses and survive.Likewise, the stress of rehydration requires appropriate mitigating cellular responses. We also explore what comparative genomics, both structural and responsive, have added to our understanding of cellular protection mechanisms induced by desiccation, and how vegetative desiccation tolerance circumvents destructive, stress-induced cell senescence.

Cryoscopy of Milk: Effect of Variations in the Method

1966 ◽  
Vol 49 (3) ◽  
pp. 511-515 ◽  
Author(s):  
R W Henningson
Keyword(s):  
Statistical Analysis ◽  
Sample Size ◽  
Freezing Point ◽  
Collaborative Study ◽  
Sample Temperature ◽  
Milk Samples ◽  
Two Samples ◽  
Temperature Rate

Abstract Bath level, sample temperature, rate of stirring, degree of supercooling, sample size, sample isolation, and refreezing of the sample were the variables in the thermistor cryoscopic method for the determination of the freezing point value of milk chosen for study. Freezing point values were determined for two samples of milk and two secondary salt standards utilizing eight combinations of the seven variables in two test patterns. The freezing point value of the salt standards ranged from –0.413 to –0.433°C and from –0.431 to –0.642°C. The freezing point values of the milk samples ranged from –0.502 to –0.544°C and from –0.518 to –0.550°C. Statistical analysis of the data showed that sample isolation was a poor procedure and that other variables produced changes in the freezing point value ranging from 0.001 to 0.011°C. It is recommended that specific directions be instituted for the thermistor cryoscopic method, 15.040–15.041, and that the method be subjected to a collaborative study.

Method for the simultaneous quantification of n-hexane metabolites: application to n-hexane metabolism determination

1996 ◽  
Vol 15 (6) ◽  
pp. 497-503 ◽  
Author(s):  
T. Soriano ◽  
M. Menéndez ◽  
P. Sanz ◽  
M. Repetto
Keyword(s):  
Similar Pattern ◽  
Analytical Procedure ◽  
Daily Basis ◽  
Practical Application ◽  
Simultaneous Quantification ◽  
Exposed Workers ◽  
Before And After ◽  
Time Requirements ◽  
The Difference

1 The described analytical procedure permits the simultaneous determination of the main n-hexane meta bolites in urine. 2-Hexanone, 2-hexanol, 2, 5-hexanediol and 2, 5-hexanedione, were chosen to dose the rats used in this study. All urine samples were collected and analysed on a daily basis, before and after acidic hydrolysis (pH 0.1) by GC/MS. 2-Hexanone, 2, 5-dimethylfurane, γ-valerolac tone and 2, 5-hexanedione were determined before hydro lysis ; 2-hexanol and 2, 5-hexanediol, after hydrolysis; and 5-hydroxy-2-hexanone and 4, 5-dihydroxy-2-hexanone were calculated by the difference between γ-valerolactone and 2, 5-hexanedione with and without hydrolysis, respectively. 2 A metabolic scheme was proposed reflecting the biotransformations undergone by the four compounds assayed. We consider 2, 5-dimethylfurane as a 'true metabolite' because the quantities detected were always greater before hydrolysis. 3 It has been reported that human and rat n-hexane metabolism follow a similar pattern. Therefore, as a practical application and without increasing either sample or time requirements, the simultaneous quantifi cation of the different metabolites and their excretion profile could provide better information about the metabolic situation of exposed workers than the determi nation of 2, 5-hexanedione alone. According to our experimental results, 4, 5-dihydroxy-2-hexanone itself would be a good toxicity indicator.

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