Biological activity of 2,4-D esters on rubber vine (Cryptostegia grandiflora): dependence on vapour pressure and molecular weight and isomerism of the alcohol substituent

1989 ◽  
Vol 40 (3) ◽  
pp. 685
Author(s):  
GJ Harvey
Keyword(s):  
Molecular Weight ◽  
Vapour Pressure ◽  
Low Molecular Weight ◽  
Straight Chain ◽  
Biological Efficacy ◽  
Cryptostegia Grandiflora ◽  
Normal Series ◽  
Branched Chain ◽  
The Relationship ◽  
Volatile Esters

The relationship between molecular structure and biological efficacy was investigated for 16 esters of 2,4-D [(2,4-dich1orophenoxy)acetic acid] on rubber vine (Cryptostegia grandiflora). These included the normal (n) or straight-chain esters from C-1 (methyl) to C-8 (octyl), the n-decyl, n-dodecyl, isobutyl, amyl (iso-pentyl), 2-ethylhexyl (iso-octyl), and the methoxy-, ethoxy-, and butoxyethyl esters. For the normal series esters, biological efficacy was found to be a function of both the molecular weight and the vapour pressure of the esters. This relationship was linear for the higher molecular weight, low volatile esters, biological efficacy decreasing with increasing molecular weight and the accompanying decrease in vapour pressure of the esters. The low molecular weight, volatile esters were more active than the higher molecular weight, low volatile esters, and increases in the vapour pressure of these low molecular weight, volatile esters were sufficient to account for the deviation from linearity of those esters. When all esters are considered, the same relationships hold but the branched-chain (iso) and chemically substituted (alkoxy alcohol) esters are less effective than the corresponding normal esters. Possible reasons for these results are discussed.

STUDIES ON THE ISOLATION AND NATURE OF THE 'TERREGENS FACTOR'

1954 ◽  
Vol 32 (1) ◽  
pp. 400-406 ◽  
Author(s):  
M. O. Burton ◽  
F. J. Sowden ◽  
A. G. Lochhead
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Ferric Iron ◽  
Test Organism ◽  
The Other ◽  
Inorganic Salts ◽  
Low Molecular Weight ◽  
Straight Chain ◽  
Heat Stable ◽  
Growth Promoting

A procedure is described for the production and concentration of the 'terregens factor' (TF), a bacterial growth promoting substance synthesized by Arthrobacter pascens and essential for the growth of Arthrobacter terregens. From culture filtrates of A. pascens cultivated in a medium of inorganic salts and sucrose, concentrates of TF may be obtained that are active at 0.001 μgm. Per ml., heat stable and contain about 12.7% nitrogen. Acid hydrolysis yielded a number of amino acids, including glutamic acid, glycine, α–alanine, valine, leucine, proline, lysine, and arginine, as well as some unidentified compounds; however, TF does not appear to be a low molecular weight straight chain peptide.Although TF contains no iron, it combines readily with ferrous or ferric iron to form reddish-brown complexes with this metal. Activity for A. terregens is shown by certain iron containing complexes as hemin, coprogen, and ferrichrome. On the other hand none is shown by cytochrome or pulcherrimin; however, aspergillic acid, structurally related to the latter, possesses some growth promoting activity for the test organism.

Stress protein content of mature Brassica seeds and their germination performance

1998 ◽  
Vol 8 (3) ◽  
pp. 347-355 ◽  
Author(s):  
Mary Bettey ◽  
W. E. Finch-Savage
Keyword(s):  
Molecular Weight ◽  
Water Stress ◽  
Seed Development ◽  
Positive Relationship ◽  
Stress Proteins ◽  
Stress Protein ◽  
Low Molecular Weight ◽  
Optimal Conditions ◽  
Seed Vigour ◽  
The Relationship

AbstractPlants respond to sub-optimal conditions by the synthesis of specific ‘stress’ proteins, and these are thought to play a role in stress tolerance. Some of these proteins accumulate during late seed development, arguably to protect against damage during post-maturation drying and subsequent imbibition, prior to germination. Seed vigour is also determined during this late stage of seed development. High vigour seeds are those that can withstand the desiccation required for storage and successfully germinate under sub-optimal conditions to establish healthy seedlings. If stress proteins are involved in tolerating stress conditions, then they are likely to be important determinants of seed vigour. In this work the relationship between seed vigour (measured by seed germination performance following rapid aging, or under water stress) in Brassica oleracea var. capitata and the content of two classes of stress protein (dehydrins and a low molecular weight heat shock protein HSP17.6) at maturity was examined. Dehydrins did not show a positive relationship with seed performance. However, the protein HSP17.6 showed a positive correlation with seed performance, and a treatment that reduced the amount of this protein in the seed also caused a reduction in subsequent seed performance.

FRACTIONATION OF LIVER SOMATOMEDIN ACTIVITY BY ULTRAFILTRATION

1974 ◽  
Vol 62 (2) ◽  
pp. 355-361 ◽  
Author(s):  
JENNIFER M. DEHNEL ◽  
P. D. McCONAGHEY ◽  
M. J. O. FRANCIS
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Weight Fraction ◽  
Low Molecular Weight ◽  
High Molecular Weight Fraction ◽  
Cartilage Growth ◽  
The Relationship ◽  
Somatomedin Inhibitors

SUMMARY Plasma somatomedin is the intermediary through which growth hormone (GH) exerts its effects on the growing skeleton. Somatomedin activity may be produced in vitro by perfusion of the liver and kidneys of rats with Waymouth's medium containing GH. The relationship between the activity of plasma somatomedin and somatomedin of hepatic and renal origin has yet to be clarified. Somatomedin from plasma can be separated into active fractions of both high and low molecular weight. Similarly, ultrafiltration of medium containing somatomedin of hepatic origin indicates the existence of two active fractions, one of high molecular weight (greater than 50000) and one of low molecular weight (less than 1000). The latter can be attributed to the release of amino acids, such as serine and glutamine, by the perfused tissue. The high molecular weight fraction is believed to represent GH-dependent somatomedin. Fractions that inhibit production of cartilage matrix are present in liver perfusates as well as in plasma. These results provide further evidence that the liver is a source of GH-dependent somatomedin in vivo. Furthermore, cartilage growth may be controlled not only by the GH-stimulated release of somatomedin by the liver, but also by its release of acid-labile somatomedin inhibitors.

Low molecular weight straight-chain amines as corrosion inhibitors

1993 ◽  
Vol 34 (8) ◽  
pp. 1251-1257 ◽  
Author(s):  
Robert D. Braun ◽  
Emilio E. Lopez ◽  
Daniel P. Vollmer
Keyword(s):  
Molecular Weight ◽  
Corrosion Inhibitors ◽  
Low Molecular Weight ◽  
Straight Chain

scholarly journals Aroma Volatile Production in Preharvest AVG-treated `Golden Delicious' Apple Fruit and the Effect of Poststorage Ethylene Treatment

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 781E-782
Author(s):  
Jun Song ◽  
Fritz Bangerth
Keyword(s):  
Ethylene Biosynthesis ◽  
Apple Fruit ◽  
Straight Chain ◽  
Ethylene Treatment ◽  
Close Relationship ◽  
Aroma Production ◽  
Branched Chain ◽  
The Relationship ◽  
Volatile Production ◽  
Apple Fruits

Changes in the profile of aroma volatiles during ripening and after ethylene treatment in apple fruit have revealed a close relationship exists between ethylene production and the timing and magnitude of volatile synthesis. Therefore, AVG (ethylene biosynthesis inhibitor) was used to study the relationship between volatile biosynthesis and metabolic processes affected by ethylene in apple fruits. AVG-treated fruit were stored either for 1 month at 2C in air or 5 months in ULO condition. During the post-storage ripening, the fruits were exposed to 50 μl·liter–1 of ethylene at least 12 h/day. Aroma production was determined at 20C. Total volatile compound production by AVG-treated fruit was much lower than that of untreated fruit. A significant increase in the production of most aroma volatile after 1 month storage in air was induced by ethylene treatment to AVG-treated fruits. I was noted that branched-chain volatile, such as 2-methylbutylacetate, which originates from branched-chain amino acids, has increased prior to butylacetate and hexylacetate, which are derived from fatty acids. Ethylene treatment was unable to stimulate the production of straight-chain volatile compounds following the 5 months of ULO storage. These results are consistent with observations suggesting apple fruit lose their sensitivity to ethylene after long ULO storage.

scholarly journals The Anti-Rotaviral Activity of Low Molecular Weight and Non-Proteinaceous Substance from Bifidobacterium longum BORI Cell Extract

2019 ◽  
Vol 7 (4) ◽  
pp. 108
Author(s):  
Yeo Ok Han ◽  
Yunju Jeong ◽  
Hyun Ju You ◽  
Seockmo Ku ◽  
Geun Eog Ji ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Molecular Weight ◽  
Cytopathic Effect ◽  
Diarrheal Disease ◽  
Bifidobacterium Longum ◽  
Cell Extract ◽  
Host Cells ◽  
Low Molecular Weight ◽  
Protein Components ◽  
The Relationship

Rotavirus infection is the most common diarrheal disease worldwide in children under five years of age, and it often results in death. In recent years, research on the relationship between rotavirus and probiotics has shown that probiotics are effective against diarrhea. A clinical trial has reported that Bifidobacterium longum BORI reduced diarrhea induced by rotavirus. The present work investigated the anti-rotaviral effect of B. longum BORI by cytopathic effect observation and real time cell analyses. Our study found that B. longum BORI showed strong anti-rotaviral effect when incubated with MA104 cells prior to viral infection, suggesting that the probiotic does in fact interfere with the interaction of viruses and host cells. It is believed that the efficacy is due to low-molecular weight and non-protein components derived from B. longum BORI. This discovery can help broaden the industrial application of B. longum BORI, which has been proven to be a safe and effective probiotic.

scholarly journals What is the Best Treatment for a Cancer Patient with Thrombosis?

2014 ◽  
Vol 8 ◽  
pp. CMO.S13386 ◽  
Author(s):  
Miguel Barbosa
Keyword(s):  
Molecular Weight ◽  
Venous Thromboembolism ◽  
Cancer Patient ◽  
Scientific Evidence ◽  
Vitamin K Antagonists ◽  
Oral Anticoagulants ◽  
Low Molecular Weight ◽  
Low Molecular Weight Heparins ◽  
Adequate Treatment ◽  
The Relationship

The relationship between venous thromboembolism and cancer has been known for many years, and there is solid scientific evidence addressing the adequate treatment of this condition in oncology patients. However, established prescribing habits, individual patient challenges, and uncertainty concerning treatment justifies poor adherence to published guidelines. This paper reviews venous thromboembolism treatment while focusing on vitamin K antagonists, low-molecular-weight heparins, and novel oral anticoagulants, namely in terms of their efficacy and limitations.

P1100IMPACT OF THE RELATIONSHIP BETWEEN LOW MOLECULAR WEIGHT PROTEINS REMOVAL EFFICIENCIES AND THE VOLUME OF ALBUMIN LEAKAGE IN HEMODIAFILTRATION THERAPY

2020 ◽  
Vol 35 (Supplement_3) ◽  
Author(s):  
Kenji Sakurai ◽  
Takeshi Saito ◽  
Hiromi Hosoya ◽  
Yoshitaka Kurihara ◽  
Kaori Kurosawa ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Removal Efficiency ◽  
High Efficiency ◽  
Low Molecular Weight ◽  
Efficient Removal ◽  
On Line ◽  
Stokes Radius ◽  
Removal Efficiencies ◽  
The Relationship ◽  
Low Molecular Weight Proteins

Abstract Background and Aims The purpose of hemodiafiltration (HDF) is to remove small- to large molecular weight solutes in order to prevent and treat complications and to improve the prognosis of dialysis patients. Especially, larger low molecular weight proteins (LMWPs) must be removed efficiently. β2-microglobulin (MG) (molecular weight [MW], 11.8 kDa: Stokes radius, 15.6A), is considered as an important marker of dialysis efficiency. However, MW of β2-MG is too small as a marker in HDF. Conversely, α1-MG (MW, 33 kDa: Stokes radius, 28.4A) is the most appropriate marker for evaluation of solute removal efficiency of HDF because of the following reasons: (1) optical molecular size; (2) not very low physiological blood concentration; (3) stable production rate; (4) removal by convection; and (5) accumulation in ESRD. Efficient removal of α1-MG without losing albumin (Alb) (MW,66 kDa: Stokes radius, 35.5A) is impossible even by HDF. In this study, we investigated the relationship between LMWP removal efficiencies and the volume of Alb leakage by analyzing the results of patients undergoing HDF. And we also evaluated the trend of the serum levels of patients who had received high-efficiency HDF for more than three years Method Eighty-seven patients who had received HDF in 2018–2019 were included. The results of HDF (a total of 435 sessions) were analyzed (blood flow rate, 261.5±28.5 mL/min; replacement fluid volume, 48.7 L/s pre-dilution on-line HDF and 14.2 L/s post-dilution on-line HDF). The removal efficiencies of β2-MG, prolactin (PRL), and α1-MG, and the volume of Alb leakage were examined. In addition, the relationship between the removal efficiency of each solute and the volume of Alb leakage was investigated. Changes in serum Alb level were analyzed in 13 patients who continued to receive high-efficiency HDF (the removal rate of α1-MG was 30% or more) for more than three years. Results Analysis of the results (mean ± SD) obtained from a total of 435 sessions (87 patients) showed that the removal rates of β2-MG, PRL, and α1-MG were 80.7 ± 4.5%, 75.8±9.4 and 33.8 ± 9.4%, respectively, and the Alb leakage was 3.9 ± 1.8 g/s. The equations of the approximate curve between Alb leakage and β2-MG, PRL, and α1-MG removal rates were expressed as follows: ï½™= 1.4197ln(x) + 78.972 (R2 = 0.0426), y = 9.7185ln(x) + 64.134 (R2 =0.4632), and ï½™™= 11.225ln(x) + 20.282 (R2 = 0.6191), respectively. These results indicate that the dynamics between Alb leakage and α1-MG removal are very similar. That is, although the molecular weight of Alb is twice as that of α1-MG, the difference in their Stokes radius is 20%; therefore, separate removal of Alb and α1-MG is impossible. The mean serum Alb level in 13 patients who received high-efficiency HDF for 3 years or longer was 3.59 ± 0.23 g/dL in January 2017 and 3.69 ± 0.28 g/dL in December 2019, revealing no changes. Conclusion The efficient removal of larger LMWPs leads to the leakage of Alb. However, an Alb leakage of 3 to 6 g/s has little influence on the serum Alb level of patients. Thus, α1-MG is the most appropriate marker of the solute removal efficiency of HDF.

ChemInform Abstract: Low Molecular Weight Straight-Chain Amines as Corrosion Inhibitors.

ChemInform ◽  
2010 ◽  
Vol 24 (41) ◽  
pp. no-no
Author(s):  
R. D. BRAUN ◽  
E. E. LOPEZ ◽  
D. P. VOLLMER
Keyword(s):  
Molecular Weight ◽  
Corrosion Inhibitors ◽  
Low Molecular Weight ◽  
Straight Chain

scholarly journals Suitability of α1-microglobulin reduction rate as a biomarker of removal efficiency of online hemodiafiltration: a retrospective cohort study

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Kenji Sakurai ◽  
Hiromi Hosoya ◽  
Yoshitaka Kurihara ◽  
Takeshi Saito
Keyword(s):  
Molecular Weight ◽  
Cohort Study ◽  
Removal Efficiency ◽  
Retrospective Cohort ◽  
Reduction Rate ◽  
Low Molecular Weight ◽  
Albumin Leakage ◽  
Maintenance Dialysis ◽  
The Relationship ◽  
Low Molecular Weight Proteins

Abstract Background Online hemodiafiltration (OL-HDF), whether in pre-dilution OL-HDF (pre-HDF) or post-dilution OL-HDF (post-HDF), is conducted to efficiently remove low molecular weight proteins from the blood of patients requiring dialysis. β2-microglobulin (β2-MG) and α1-microglobulin (α1-MG) are used as biomarkers to evaluate removal efficiency of OL-HDF. We aimed to evaluate the relationship between β2-MG and α1-MG reduction rates and the amount of albumin leakage. Furthermore, we statistically analyzed the relationship between the α1-MG reduction rate and α1-MG removal amount, and its suitability as a biomarker for evaluating the removal efficiency of OL-HDF. Methods We collected the results of regularly conducted routine evaluations to assess the efficiency of OL-HDF from cases of patients undergoing maintenance dialysis at our clinic from 2018 to 2019. Data on was collected on both pre-HDF and post-HDF sessions. β2-MG and α1-MG reduction rates were analyzed. Regression analysis on reduction rates showed a significant correlation between the α1-MG reduction rate and the α1-MG removal amount. Results We conducted 435 tests on OL-HDF efficiency in 87 cases undergoing maintenance dialysis at our clinic in 2018 and 2019. There were 80.7 ± 4.5% for the β2-MG reduction rate, 33.8 ± 9.4% for the α1-MG reduction rate, and 3.9 ± 1.8 g/s for the amount of albumin leakage. There was no correlation between the β2-MG reduction rate and the α1-MG reduction rate, or between the amount of albumin leakage and β2-MG reduction rate. Conclusion α1-MG reduction rate was found to correlate with its removal amount, demonstrating its suitability as a biomarker for evaluating the removal efficiency of OL-HDF. Trial registration Retrospectively registered.

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