A Comprehensive Review of Ribosomal Hibernation and Associated Factors in Escherichia coli | Chapter 3 | Microbiology and Biotechnology Research: An Overview Vol. 1

Bacteria have developed sophisticated adaptive systems to survive during various environmental changes, including nutrient starvation, temperature shock, osmolarity changes, and rapid pH changes. Bacteria convert active 70S ribosomes to inactive 100S ribosomes to survive under various stress conditions. Recently, high-resolution structures of 100S ribosomes from various bacteria have been reported, improving the understanding of ribosome hibernation. In this review, previous findings on the 100S ribosome and related protein factors in E. coli are described. This study is an attempt to integrate the hibernation stage into the ribosome cycle and discuss the elaborate stress response pathway involved in bacterial translational control. The state, in which the ribosome loses its translational activity, is known as ribosomal hibernation. In gammaproteobacteria such as Escherichia coli, ribosome modulation factor (RMF) and hibernation-promoting factor (HPF) are involved in forming 100S ribosomes. The expression of ribosome modulation factor is regulated by (p)ppGpp (which is induced by amino acid starvation), cAMP-CRP (which is stimulated by reduced metabolic energy), and transcription factors involved in biofilm formation and depletion of metal-ions. (p)ppGpp regulates transcriptional activity and decreases ribosome biosynthesis for environmental adaptation by interacting with RNA polymerase. This indicates that the formation of 100S ribosomes is an important strategy for bacterial survival under various stress conditions. The genes for the ribosomal hibernation factors are scattered throughout the E. coli genome and use different expression pathways. Therefore, determining the expression mechanism of protein factors, such as RMF and HPF, which contribute to the formation of 100S ribosomes, will be useful for considering the effective use of antibiotics.

 

Author (s) Details

 

Yasushi Maki
Department of Physics, Osaka Medical and Pharmaceutical University, Takatsuki 569-8686, Japan.

 

Hideji YoshidaA
Department of Physics, Osaka Medical and Pharmaceutical University, Takatsuki 569-8686, Japan.

 

Please see the book here:- https://doi.org/10.9734/bpi/mbrao/v1/4673

Stunting-Induced Compensatory Growth in Aquaculture: Mechanisms and Implications | Book Publisher International

Compensatory growth (CG) is an elevated growth rate often observed in fish that have previously experienced stress and returned to normal conditions. To induce CG responses, fish must undergo a catabolic phase, where they utilize endogenous energy reserves. In nature, fish encounter catabolic phases due to food limitations, migration and predation. In aquaculture, the catabolic phase is achieved through stunting practices such as feed restrictions, environmental manipulation and crowding stress. When fish experience the catabolic phase in captivity, they undergo various behavioural, physiological and biochemical changes to cope with the altered environmental conditions. Behavioural changes include reduced swimming and locomotion activities. Physiological adjustments involve metabolic changes such as reduced circulation of proteins, antibodies, enzymes and other molecular compounds. In biochemical alterations, fish utilize endogenous energy resources, such as lipids and proteins, which affect their overall nutritional composition. However, when stressed fish return to favourable conditions, they exhibit a CG response and rapidly restore their lost body weight, metabolic compounds and endogenous energy reserves. The effectiveness of the CG response can vary significantly depending on several factors, including the specific fish species, duration and severity of the stunting practice, as well as the conditions during the refeeding phase. This phenomenon has been harnessed in aquaculture to produce stunted fish seed. Extensive research on CG responses in fish over the past few decades has yielded inconsistent results, fostering debate over the practical application of CG response in aquaculture. To better understand and potentially leverage this phenomenon in aquaculture practices, it is crucial to critically examine the physiological changes that occur in fish during both stunting and post-stunting phases. This book aims to provide a comprehensive analysis of the actual changes occurring in fish during the stunting and post-stunting phases and explore the potential applications of CG responses in aquaculture, offering insights for more efficient and sustainable fish farming practices.

 

Author (s) Details

Suresh Babu Padinhate Purayil
ICAR-Central Marine Fisheries Research Institute, Kochi, Kerala, India.

 

Ande P. Muralidhar
ICAR-Central Institute of Fisheries Education, Versova, Mumbai, Maharashtra, India.

 

Karthireddy Syamala
ICAR-Central Institute of Fisheries Education, Versova, Mumbai, Maharashtra, India.

 

Somu Sunder Lingam R
Tamil Nadu Dr. J. Jayalalithaa Fisheries University, Nagapattinam, Tamil Nadu, India.

 

 

Please see the book here:- https://doi.org/10.9734/bpi/mono/978-93-49473-12-6

A Comparative Study of Attenuation of Hypertensive Response with Esmolol and Labetalol in Low doses in Orotracheal Intubation | Chapter 10 | New Frontiers in Medicine and Medical Research Vol. 16

 In this prospective, randomised, double-blind, comparative clinical trial, Esmolol and Labetalol were assessed for attenuation of sympathomimetic reactivity to laryngoscopy and intubation at low doses.

Materials and Procedures: The participants in this study were 50 ASA 1 patients of either gender undergoing elective surgery under general anaesthetic. Patients were randomly assigned to one of two groups prior to induction: group E received intravenous Esmolol (0.5 mg/kg) or group L received intravenous Labetalol (0.25 mg/kg), and hemodynamic parameters were monitored according to the procedure to determine stress response to laryngoscopy and intubation.

The demographic profiles of both research groups were similar as a result of the findings. Instat version 3.10 was used for statistical calculations. The study's data was analysed utilising statistical methods including mean and standard deviation. Esmolol (0.5 mg/kg) and Labetalol (0.25 mg/kg) significantly reduced the increase in heart rate, systolic blood pressure, and RPP during laryngoscopy and intubation. The difference in DBP and MAP values, however, was not statistically significant.

Conclusion: Our clinical trial found that intravenous Labetalol (0.25 mg/kg) is more effective than intravenous Esmolol (0.5 mg/kg) at reducing the sympathomimetic reaction to laryngoscopy and intubation at lower doses. Esmolol is commonly used to elicit an intubation response at doses of 2-4 mg/kg, whereas labetalol has been studied at doses of 0.25, 0.5, 0.75, and 1 mg/kg [1].

Author (S) Details

Suruchi Ambasta
Deptarment of Anaesthesia, Mayo Institute of Medical Sciences, Lucknow, Uttar Pradesh, India.

Swagat Mahapatra
Deptartment of Orthopaedics, Dr. Ram Manohar Lohia Institute of Medical Sciences, Lucknow, Uttar Pradesh, India.

View Book :- https://stm.bookpi.org/NFMMR-V16/article/view/3784