killing rate
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2021 ◽  
Vol 923 (1) ◽  
pp. 012007
Author(s):  
Meeri Kadhim Al-Fatlawi ◽  
Iktifaa Naeem Jasim ◽  
Nidaa Saud AlShammary ◽  
Khudheyer A. A. Alnomani

Abstract This study conduct in Al-Muthanna governorate to assess five concentrations of Bacillus thurngensisagonist Hyperapostica. The results showed the presence of Bacillus thurngensisin all the studied sites of Lake Sawa in Muthanna Governorate, and the rates of its presence were close to the same sites, and the rate of its presence in those sites was 35%, and its highest rate was recorded in the north and east of the lake, as it reached 40% and the lowest amounted to 30% in the two sites south and west site. The results of the study showed that five concentrations were taken from bacterial isolates of B. thuringiensisdiffered in the rates of killing larvae, pupae and adults of the insect Hyperapostica in vitro, Where the concentrate 1.7 × 103 spore/ml was characterized by a higher killing ratecompared to the four studied concentrations, the killing rates were (75.750, 71.080, 69.79, 64,361, 49.117 and 42,060)% for the first larval instar, the second larval instar, the third larval instar, the fourth larval instar, and the pupae, respectively, and the lowest killing rate recorded 6.873% at concentration 0.64 × 107after 24 hours of treatment.


2021 ◽  
pp. 3350-3357
Author(s):  
Rabah Hassan Saady ◽  
Abdulrahman Jihad Mansoor

       The results of the present study show the biological effects of ethyl elcoholic and aquatic extracts as well as alkaloids compounds  of Atriplex helmius and Capparis spinosa  roots. The results demonstrated the superiority of the cold aqueous extract of C. capparis at the highest concentration of 20 mg / ml, as the killing rate was 81.16% for the second  larval instar of Cx. pipiens after 72 hours of exposure. While, the killing rate caused by the same treatment was 79.52% for the third larval instar. The results also showed the superiority of the alcoholic extract against C.  spinosa , as the killing rate reached 98.55% for the second larval instar after 72 hours of treatment at a concentration of 20 mg/ml. As for A. halmius extract, the same treatment caused the lowest killing rate of 89.27% ​​ for the third instar of Cx. pipiens. The study also showed significant effects of the raw alkaline compounds’ extracts of A. halimus  roots on the killing of non-adult instars of Cx. pipiens L. The highest rate of mortality observed was 88.54% at the highest concentration of 20 mg /ml at the second instar. Also, significant effects of raw alkaline compounds’ extracts of C. spinosa roots were observed. The highest mortality was 69.21% at the highest concentration of 20 mg/ml for the third larval instar,                                                         


2021 ◽  
Vol 58 (3) ◽  
pp. 708-720
Author(s):  
Shoou-Ren Hsiau ◽  
May-Ru Chen ◽  
Yi-Ching Yao

AbstractWe consider a birth–death process with killing where transitions from state i may go to either state $i-1$ or state $i+1$ or an absorbing state (killing). Stochastic ordering results on the killing time are derived. In particular, if the killing rate in state i is monotone in i, then the distribution of the killing time with initial state i is stochastically monotone in i. This result is a consequence of the following one for a non-negative tri-diagonal matrix M: if the row sums of M are monotone, so are the row sums of $M^n$ for all $n\ge 2$ .


2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Devabhaktuni Srikrishna ◽  
Kris Sachsenmeier

AbstractIf each cancer cell produces on average more than one cancer cell, we see a net growth of the tumors and metastases and vice versa. We review recent clinical results for microsatellite stable metastatic colorectal cancer (MSS-mCRC) suggesting immunotherapy combinations with personalized vaccines, checkpoint inhibitors, targeted therapies, multikinase inhibitors, chemotherapies, and radiation that simultaneously slow cancer cell growth rate and enhance T cell killing rate of cancer cells may in future synergize to control the disease.


Primates ◽  
2021 ◽  
Author(s):  
Laura Martínez-Íñigo ◽  
Pauline Baas ◽  
Harmonie Klein ◽  
Simone Pika ◽  
Tobias Deschner

AbstractIntercommunity competition in chimpanzees (Pan troglodytes) has been widely studied in eastern (P. t. schweinfurthii) and western (P. t. verus) communities. Both subspecies show hostility towards neighboring communities but differ in rates of lethal attacks and female involvement. However, relatively little is known about the territorial behavior of the two other subspecies, central (P. t. troglodytes) and Nigeria-Cameroon chimpanzees (P. t. ellioti). Here, we present the first insights into intercommunity interactions of individuals of a community of central chimpanzees living in the Loango National Park in Gabon. The presence of individuals of neighboring communities in the Rekambo home range was assessed using 27 camera traps. Information was compiled on intergroup interactions recorded before (2005–2016) and after (January 2017–June 2019) the habituation of the community. Individuals from neighboring communities entered the core area, where nine out of 16 recorded intercommunity encounters occurred. Males were the main participants in territorial patrols and intercommunity aggressions. Females were part of all six territorial patrols recorded and dependent offspring participated in five patrols. Females were involved in intercommunity aggression in five out of twelve recorded encounters in which there was visual contact between communities. While the intercommunity encounter rate was lower than that reported across most other long-term chimpanzee sites, the annual intercommunity killing rate was among the highest. These results suggest that the frequency of lethal attacks at Loango is comparable to that reported for the eastern subspecies. In contrast, female involvement in intercommunity interactions mirrors that of the western subspecies.


Author(s):  
Oluwatoyosi Ezekiel OLAWALE ◽  
Olubukola OLUSOLA-MAKINDE ◽  
Muftau Kolawole OLADUNMOYE

This study investigated the synergistic antibacterial potentials of Ocimum gratissimum (O. gratissimum) leaf acetone extract, honey, and ciprofloxacin against some multiple antibiotic-resistant bacteria. Multiple antibiotic-resistant bacterial isolates from stool samples of diarrhea patients and their typed cultures were subjected to inhibitory assay by mixtures of extract and honey, extract and ciprofloxacin, honey and ciprofloxacin, and extract, honey and ciprofloxacin using tube dilution method. Killing rate and mechanisms of action of the mixtures on the susceptible pathogens were determined. The multiple antibiotic resistance indices of the test organisms (MARI) ranged from 0.7 to 1.0. Extract, honey, and ciprofloxacin mixture at ratio 1:1:1 exerted the lowest minimum inhibitory concentration on E. coli, P. aeruginosa ATCC 10145, E. coli ATCC 25922, and S. typhi ATCC 14028 at 1.56×10-3 mg/mL compared with ciprofloxacin (3.13×10-3 mg/mL). Highest potassium, sodium, and protein leakage was induced by extract and honey mixture (97.4 cmol/g) in E. coli, extract, honey, and ciprofloxacin mixture (65.2 cmol/g) in B. cereus, and extract, honey, and ciprofloxacin mixture (21.6 mg/mL) in B. cereus, respectively. Extract, honey, and ciprofloxacin mixture exerted highest killing rate on B. cereus after 24 h (1.3×101 cfu/mL). These findings revealed a high synergistic antibacterial potential of O. gratissimum leaf acetone extract, honey, and ciprofloxacin against multiple drug-resistant bacteria, thus, implying their potential use in diarrhea treatment.


2021 ◽  
Vol 144 ◽  
pp. 110750
Author(s):  
Najma Ahmed ◽  
Nehad Ali Shah ◽  
Somaye Taherifar ◽  
F.D. Zaman

2021 ◽  
Author(s):  
Yong Chen ◽  
Yuyu Wang ◽  
Zhendong Wang ◽  
Qiang Zhang ◽  
Qiuxia Han

Abstract Tuning the ratio of complementary biocidal groups in a composite unit is proved to be a tactic to better minimize their weaknesses to realize higher synergism. A silane monomer, 6-(pyridin-4-yl)-3-(3-(trimethoxysilyl)propyl)-1,3,5-triazinane-2,4-dione, with biocidal precursors of one pyridinium and two N-chloramine sites was synthesized, hydrolyzed and dehydrocondensed on cotton cellulose. Specially, isonicotinaldehyde was ammonolyzed with biuret to produce 6-(pyridin-4-yl)-1,3,5-triazinane-2,4-dione that subsequently reacted with (γ-chloropropyl)trimethoxysilane to synthesize the silane monomer through nucleophilic substitution. The modifier on cotton was quaternized and chlorinated to transform the one pyridine and two amide N−H structures in each unit of the silicone to pyridinium and N-chloramine counterparts. The cationic pyridinium increases the hydrophilicity of the unit and electrically draws anionic bacteria to its two adjacent highly fatal N-chloramine sites, achieving a faster contact-killing rate than not only monofunctionality but also basic synergistic integration of one cationic center and one N-chloramine. This phenomenon is therefore referred to as “intensified synergism” and provides crucial information for the design of more powerful biocides. The pyridinium/di-N-chloramine silicone coating exhibited extraordinary durability towards UV irradiation, washing cycles and long-term storage due to the good UV resistance and chemical inertness of pyridinium and silicone backbone.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 265
Author(s):  
Nattakanwadee Khumpirapang ◽  
Srikanjana Klayraung ◽  
Singkome Tima ◽  
Siriporn Okonogi

The aim of the present study was to develop a microemulsion (ME) containing Alpinia galanga oil (AGO), 1,8-cineole (C), or methyl eugenol (M) as an active pharmaceutical ingredient (API) for enhancing their antimicrobial activities. Agar diffusion, broth microdilution, and killing kinetics were used for antimicrobial evaluations. The ME composed of 30% API, 33.4% Tween 80, 16.6% ethanol, and 20% water appeared as translucent systems with droplet size and polydispersity index of 101.1 ± 1.3 nm and 0.3 ± 0.1, 80.9 ± 1.1 nm and 0.4 ± 0.1, and 96.6 ± 2.0 nm and 0.2 ± 0.1 for ME-AGO, ME-C, and ME-M, respectively. These ME formulations showed minimum bacterial concentrations of 3.91–31.25 µg/mL and 50% fungal inhibition concentrations of 1.83 ± 0.27–0.46 ± 0.13 µg/mL, 2–4 times stronger, and faster kinetic killing rate than their respective API alone. Keeping the ME formulations at 4 °C, 25 °C, and 40 °C for 12 weeks did not affect their activities against fungi and Gram-negative bacteria, but the high temperature of 40 °C decreased their activities against Gram-positive bacteria. It is concluded that ME is a promising delivery system for AGO and its major compounds to enhance their water miscibility and antimicrobial activities.


2021 ◽  
Vol 19 (2) ◽  
pp. 1559-1587
Author(s):  
G. V. R. K. Vithanage ◽  
◽  
Hsiu-Chuan Wei ◽  
Sophia R-J Jang ◽  

<abstract><p>A mathematical model of tumor-immune system interactions with an oncolytic virus therapy for which the immune system plays a twofold role against cancer cells is derived. The immune cells can kill cancer cells but can also eliminate viruses from the therapy. In addition, immune cells can either be stimulated to proliferate or be impaired to reduce their growth by tumor cells. It is shown that if the tumor killing rate by immune cells is above a critical value, the tumor can be eradicated for all sizes, where the critical killing rate depends on whether the immune system is immunosuppressive or proliferative. For a reduced tumor killing rate with an immunosuppressive immune system, that bistability exists in a large parameter space follows from our numerical bifurcation study. Depending on the tumor size, the tumor can either be eradicated or be reduced to a size less than its carrying capacity. However, reducing the viral killing rate by immune cells always increases the effectiveness of the viral therapy. This reduction may be achieved by manipulating certain genes of viruses via genetic engineering or by chemical modification of viral coat proteins to avoid detection by the immune cells.</p></abstract>


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