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1.
Eur J Pharmacol ; 980: 176828, 2024 Oct 05.
Article in English | MEDLINE | ID: mdl-39094924

ABSTRACT

Induction of resistin-like molecule ß (Relm-ß) and mitofusin 2 (MFN2) mediated aberrant mitochondrial fission have been found to be involved in the pathogenesis of pulmonary arterial hypertension (PAH). However, the molecular mechanisms underlying Relm-ß regulation of MFN2 therefore mitochondrial fission remain unclear. This study aims to address these issues. Primary cultured PASMCs and monocrotaline (MCT)-induced PAH rats were applied in this study. The results showed that Relm-ß promoted cells proliferation in PASMCs, this was accompanied with the upregulation of USP18, Twist1 and miR-214, and downregulation of MFN2. We found that Relm-ß increased USP18 expression which in turn raised Twist1 by suppressing its proteasome degradation. Elevation of Twist1 increased miR-214 expression and then reduced MFN2 expression and mitochondrial fragmentation leading to PASMCs proliferation. In vivo study, we confirmed that Relm-ß was elevated in MCT-induced PAH rat model, and USP18/Twist1/miR-214/MFN2 axis was altered similar as in vitro. Targeting this cascade by Relm-ß receptor inhibitor Calhex231, proteasome inhibitor MG-132, Twist1 inhibitor Harmine or miR-214 antagomiR prevented the development of pulmonary vascular remodeling and therefore PAH in MCT-treated rats. In conclusion, we demonstrate that Relm-ß promotes PASMCs proliferation and vascular remodeling by activating USP18/Twist1/miR-214 dependent MFN2 reduction and mitochondrial fission, suggesting that this signaling pathway might be a promising target for management of PAH.


Subject(s)
Cell Proliferation , GTP Phosphohydrolases , MicroRNAs , Mitochondria , Rats, Sprague-Dawley , Signal Transduction , Twist-Related Protein 1 , Ubiquitin Thiolesterase , Animals , MicroRNAs/genetics , MicroRNAs/metabolism , Male , Rats , Ubiquitin Thiolesterase/metabolism , Ubiquitin Thiolesterase/genetics , Twist-Related Protein 1/metabolism , Twist-Related Protein 1/genetics , Mitochondria/metabolism , Mitochondria/drug effects , GTP Phosphohydrolases/metabolism , Signal Transduction/drug effects , Cell Proliferation/drug effects , Mitochondrial Dynamics/drug effects , Pulmonary Arterial Hypertension/metabolism , Pulmonary Arterial Hypertension/chemically induced , Pulmonary Arterial Hypertension/pathology , Pulmonary Arterial Hypertension/physiopathology , Monocrotaline/toxicity , Intercellular Signaling Peptides and Proteins/metabolism , Myocytes, Smooth Muscle/drug effects , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , Nuclear Proteins/metabolism , Nuclear Proteins/genetics , Hypertension, Pulmonary/chemically induced , Hypertension, Pulmonary/metabolism , Hypertension, Pulmonary/pathology , Hypertension, Pulmonary/physiopathology , Pulmonary Artery/drug effects , Pulmonary Artery/pathology , Pulmonary Artery/metabolism , Mitochondrial Proteins
2.
Genome Med ; 16(1): 103, 2024 Aug 19.
Article in English | MEDLINE | ID: mdl-39160568

ABSTRACT

BACKGROUND: Determining the impact of somatic mutations requires understanding the functional relationship of genes acquiring mutations; however, it is largely unknown how mutations in functionally related genes influence each other. METHODS: We employed non-synonymous-to-synonymous or dNdS ratios to evaluate the evolutionary dependency (ED) of gene pairs, assuming a mutation in one gene of a gene pair can affect the evolutionary fitness of mutations in its partner genes as mutation context. We employed PanCancer- and tumor type-specific mutational profiles to infer the ED of gene pairs and evaluated their biological relevance with respect to gene dependency and drug sensitivity. RESULTS: We propose that dNdS ratios of gene pairs and their derived cdNS (context-dependent dNdS) scores as measure of ED distinguishing gene pairs either as synergistic (SYN) or antagonistic (ANT). Mutation contexts can induce substantial changes in the evolutionary fitness of mutations in the paired genes, e.g., IDH1 and IDH2 mutation contexts lead to substantial increase and decrease of dNdS ratios of ATRX indels and IDH1 missense mutations corresponding to SYN and ANT relationship with positive and negative cdNS scores, respectively. The impact of gene silencing or knock-outs on cell viability (genetic dependencies) often depends on ED, suggesting that ED can guide the selection of candidates for synthetic lethality such as TCF7L2-KRAS mutations. Using cell line-based drug sensitivity data, the effects of targeted agents on cell lines are often associated with mutations of genes exhibiting ED with the target genes, informing drug sensitizing or resistant mutations for targeted inhibitors, e.g., PRSS1 and CTCF mutations as resistant mutations to EGFR and BRAF inhibitors for lung adenocarcinomas and melanomas, respectively. CONCLUSIONS: We propose that the ED of gene pairs evaluated by dNdS ratios can advance our understanding of the functional relationship of genes with potential biological and clinical implications.


Subject(s)
Evolution, Molecular , Mutation , Neoplasms , Humans , Neoplasms/genetics , Silent Mutation
3.
Front Microbiol ; 15: 1435834, 2024.
Article in English | MEDLINE | ID: mdl-39139380

ABSTRACT

Background: Douzhi, a traditional Chinese fermented beverage, features microbial communities primarily composed of lactic acid bacteria (LAB). As fermented foods continue to gain recognition and popularity, douzhi is attracting growing interest. However, investigation of the critical aspects of douzhi's fermentation processes, including fermentation characteristics and microbial community dynamics, remains vital for enhancing food safety and quality for douzhi, as well as for similar fermented food products. Method: In this study, we collected douzhi microbial communities from four chain stores, using them as fermentation starter cultures. The microbial dynamics of the fermentation were analyzed, focusing on the inoculation of LAB strains and the transition from a mung bean-based matrix to skimmed milk. The metabolomic profiles of the fermented mung bean matrices were also studied. Results: Douzhi samples obtained from representative chain stores were found to be overwhelmingly dominated by LAB. When inoculated along with the douzhi community, both LAB strains exhibited notable and substantial reductions in the pH value of the designated mung bean matrices compared to those inoculated indigenous microbiota. Specifically, Lactiplantibacillus plantarum CGMCC 1.1856 retained its population, whereas Pediococcus pentosaceus CGMCC 1.2695 exhibited a decrease in relative abundance. Using skimmed milk as a fermentation substrate instead of the mung bean matrix resulted in significant shifts in microbial communities, particularly leading to an increase in Escherichia sp. The metagenomic analyses and functional predictions illustrated that various metabolic functions were enhanced during the fermentation process due to LAB inoculation. The liquid chromatography-mass spectrometry based metabolomic analysis revealed that the inoculation of Lactiplantibacillus plantarum and Pediococcus pentosaceus in mung bean matrix did not introduce new metabolites but significantly altered the concentration and profile of existing metabolites, especially increased low molecular carbohydrates, which may enhance the nutritional potential of the fermented product. Discussion: This study examines the microbial dynamics of douzhi microbiota fermentation, emphasizing the role of lactic acid bacteria in enhancing fermentation activity and metabolite profiles. These insights contribute to improving manufacturing processes and ensuring the safety and quality of douzhi and similar fermented foods.

4.
Food Chem X ; 23: 101658, 2024 Oct 30.
Article in English | MEDLINE | ID: mdl-39139486

ABSTRACT

Fermentative features of doenjang-meju, a traditional Korean soybean brick, were investigated over 45 days via genome-centered metatranscriptomics. The pH value rapidly decreased within 10 days and successively increased after 20 days, along with an initial bacterial growth, including lactic acid bacteria, and subsequent fungal growth, suggesting their association. Polysaccharides and lipids underwent degradation, and amino acids, free sugars, and organic acids increased during the early stage. Metagenome analysis identified Aspergillus, Bacillus, Enterococcus, Staphylococcus, and Leuconostoc as major microbes, which were isolated and genome-sequenced. Metatranscriptomic analysis revealed the major roles of Bacillus and Enterococcus during the early period, shifting to Aspergillus dominance after 10 days. Metabolic pathway reconstruction and transcriptional analysis reveal that Aspergillus primarily decomposed polysaccharides to free sugars; Aspergillus and Bacillus metabolized lipids, free sugars, and organic acids generated by Enterococcus; and Aspergillus and Bacillus were instrumental in amino acid metabolism: their contributions varied by compounds and pathways.

5.
Nat Prod Bioprospect ; 14(1): 45, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-39143298

ABSTRACT

Three new ent-kaurane diterpenoids, silvaticusins A-C (1-3), along with a new ent-kaurane dimer silvaticusin D (4) were isolated from the aerial parts of Isodon silvaticus. The structures of these new compounds were established mainly by comprehensive analysis of their NMR and MS data. The absolute configuration of compounds 1 and 4 were determined using a single-crystal X-ray diffraction and computational methods, respectively. Compounds 2 and 3 were found to exhibit remarkable cytotoxic effects against five human tumor cell lines (HL-60, A-549, SMMC-7721, MDA-MB-231, and SW-480), with IC50 values spanning from 1.27 ± 0.08 to 7.52 ± 0.33 µM.

6.
J Agric Food Chem ; 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-39148227

ABSTRACT

Fulvic acids (FAs) have been commercially used in cosmetics and agronomy due to their unique biological activities, such as plant stimulation and anti-inflammatory effects. However, the extraction sources of FAs, such as peat, are currently limited. Consequently, new extraction methods using renewable resources need to be developed, while reproducing the biological functions. Here, ionic liquids (ILs) effectively extracted fulvic-like substances (FLSs) from wood sawdust. The overall molecular weight distributions of FLSs were similar to those of commercial FAs, and key organic groups (e.g., aromatic, phenolic, and methoxy groups) were also found to be shared between commercial FAs and FLSs. Detailed compositional analysis revealed by high-resolution mass spectrometry showed that the extracts contain both lignin-like and lipid-like molecules, while commercial FAs are biased toward lignin-like and carbohydrate-like molecules. FLSs generally showed better and similar performance in radical scavenging activity against ABTS+· and H2O2. Fibroblast proliferation and lettuce growth enhancements were also observed with the extract containing 1-ethyl-3-methylimidazolium acetate and triethylammonium hydrogen sulfate, respectively, which performed better than commercial FAs. Immunofluorescence staining of in vitro human follicle dermal papilla cells supports that coexpression of hair growth-related proteins can be accelerated with FLSs, and this effect was further evidenced by in vivo mouse model experiments. Finally, the reusability of ILs in the extraction process was confirmed by analyzing the structural features of FLSs from each recycling. Our findings indicate that ILs are useful for obtaining biologically functional fulvic analogs from renewable plant sources.

7.
J Clin Med ; 13(15)2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39124548

ABSTRACT

Background: We aimed to elucidate the quantitative relationship between the neuromuscular blockade depth and intraoperative motor-evoked potential amplitudes. Methods: This prospective, single-arm, open-label, observational study was conducted at a single university hospital in Seoul, Korea, and included 100 adult patients aged ≥19 years undergoing brain tumor removal surgery under general anesthesia. We measured the neuromuscular blockade degree and motor-evoked potential amplitude in the deltoid, abductor pollicis brevis, tibialis anterior, and abductor hallucis muscles until dural opening. Results: The pharmacokinetic-pharmacodynamic model revealed the exposure-response relationship between the rocuronium effect-site concentration and motor-evoked potential amplitudes. The mean motor-evoked potential amplitudes decreased proportionally with increasing neuromuscular blockade depth. As the mean amplitude increased, the coefficient of variation decreased bi-exponentially. The critical ratio of the first evoked response to the train-of-four stimulation (T1)/control response (Tc) thresholds beyond which the coefficient of variation exhibited minimal change were found to be 0.63, 0.65, 0.68, and 0.63 for the deltoid, abductor pollicis brevis, tibialis anterior, and abductor hallucis muscles, respectively. Conclusions: Our results reveal that the motor-evoked potential amplitude exhibits deterioration proportional to the degree of neuromuscular blockade. In light of the observed bi-exponential decline of the coefficient of variation with the motor-evoked potential amplitude, we recommend maintaining a T1/Tc ratio higher than 0.6 for partial neuromuscular blockade.

8.
Food Chem X ; 23: 101654, 2024 Oct 30.
Article in English | MEDLINE | ID: mdl-39170068

ABSTRACT

The key odorants contributing to the warmed-over flavor (WOF) of reheated precooked stewed beef were characterized using a sensomics approach. Overall, 36 odorants were identified, and based on flavor dilution factors, odor activity values, aroma recombination, and omission test, 11 compounds mainly derived from lipid oxidation were characterized as the key odorants contributing to the formation of WOF. In particular, 3-(methylthio)propanal, which was positively correlated with meaty aroma, was implicated in an overall increase in WOF. Thus, these odorants were elected as potential markers of WOF in the reheated precooked stewed beef. In summary, the WOF of the precooked stewed beef could be attributed to an overall increase in lipid oxidation products and a decrease in the odorants with desirable aromas. The characterization of WOF in precooked stewed beef will aid in the flavor quality control of precooked stewed beef dishes.

9.
China CDC Wkly ; 6(31): 767-771, 2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39118872

ABSTRACT

What is already known on this topic?: A new conceptual term, small and vulnerable newborns (SVN), bringing preterm birth, small for gestational age (SGA), or low birth weight (LBW) together is being advocated for assessing whether a child is at high risk. What is added by this report?: According to the new conceptual term, the increasing incidence of high-risk newborns (from 9.82% to 10.96%) has been observed among 2,005,408 newborns over the period from 2013 to 2022, which is higher than using any of the three definitions of SVN. Maternal age ≥35, primiparity, and multiple births are high risks for SVN. What are the implications for public health practice?: The new conceptual framework should be used to better assess the number of high-risk newborns. Attention should be paid to multiple births to prevent preterm-related SVN. To reduce term newborns who are SGA, we need to be concerned not only with multiple pregnancies but also with first-time mothers.

10.
Phytochemistry ; 228: 114229, 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39127395

ABSTRACT

Scoparodane C (1), a diterpenoid with a rare 3,4-seco-3-nor-2,11-epoxy-ent-clerodane scaffold, was obtained from the aerial parts of Isodon scoparius, along with isocopariusines A-E (2-6), five ent-clerodanoids featuring a 5/6-fused ring system, and isocopariusines F-H (7-9), three common ent-clerodanoids. The structures of these previously undescribed compounds were established by a combination of spectroscopic analysis, X-ray diffraction, chemical derivatization, and quantum chemical calculation. Remarkably, isocopariusine B (3) showed strong resistance reversal activity against fluconazole-resistant Candida albicans.

11.
Medicine (Baltimore) ; 103(33): e39266, 2024 Aug 16.
Article in English | MEDLINE | ID: mdl-39151510

ABSTRACT

RATIONALE: Congenital sensorineural hearing loss is a significant global health issue, primarily driven by genetic factors, such as mutations in the GJB2 gene. This report presents a Chinese girl with congenital deafness and a novel mutation of the GJB2 gene. PATIENT CONCERNS: A newborn Chinese girl exhibited signs of congenital deafness. DIAGNOSIS: Congenital deafness was confirmed through comprehensive newborn hearing screenings that included otologic, audiologic, and physical examinations. Genetic analysis revealed a compound heterozygous mutation involving c.188delT and c.235delC in the GJB2 gene, indicating a genetic basis for her hearing loss. INTERVENTIONS: The patient underwent cochlear implantation, which resulted in stable auditory outcomes. OUTCOMES: Despite follow-up difficulties, stable auditory outcomes were achieved post-cochlear implantation, highlighting the potential efficacy of this intervention in GJB2-related hearing loss. LESSONS: This case study enriches our understanding of GJB2 mutations and underscores the critical role of genetic testing in diagnosing congenital sensorineural hearing loss. It emphasizes the necessity for early intervention and sustained interdisciplinary care to enhance the quality of life for patients with genetic hearing impairment.


Subject(s)
Connexin 26 , Connexins , Hearing Loss, Sensorineural , Humans , Female , Hearing Loss, Sensorineural/genetics , Hearing Loss, Sensorineural/diagnosis , Connexins/genetics , Infant, Newborn , Mutation , Cochlear Implantation , China , Asian People/genetics , East Asian People
12.
Nanomedicine (Lond) ; : 1-21, 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39163266

ABSTRACT

Regenerative therapy, a key area of tissue engineering, holds promise for restoring damaged organs, especially in bone regeneration. Bone healing is natural to the body but becomes complex under stress and disease. Large bone deformities pose significant challenges in tissue engineering. Among various methods, scaffolds are attractive as they provide structural support and essential nutrients for cell adhesion and growth. Collagen and hydroxyapatite (HA) are widely used due to their biocompatibility and biodegradability. Collagen and nano-scale HA enhance cell adhesion and development. Thus, nano HA/collagen scaffolds offer potential solutions for bone regeneration. This review focuses on the use and production of nano-sized HA/collagen composites in bone regeneration.


[Box: see text].

14.
Microbiol Res ; 287: 127865, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39121702

ABSTRACT

The gut microbiota, mainly resides in the colon, possesses a remarkable ability to metabolize different substrates to create bioactive substances, including short-chain fatty acids, indole-3-propionic acid, and secondary bile acids. In the liver, bile acids are synthesized from cholesterol and then undergo modification by the gut microbiota. Beyond those reclaimed by the enterohepatic circulation, small percentage of bile acids escaped reabsorption, entering the systemic circulation to bind to several receptors, such as farnesoid X receptor (FXR), thereby exert their biological effects. Gut microbiota interplays with bile acids by affecting their synthesis and determining the production of secondary bile acids. Reciprocally, bile acids shape out the structure of gut microbiota. The interplay of bile acids and FXR is involved in the development of multisystemic conditions, encompassing metabolic diseases, hepatobiliary diseases, immune associated disorders. In the review, we aim to provide a thorough review of the intricate crosstalk between the gut microbiota and bile acids, the physiological roles of bile acids and FXR in mammals' health and disease, and the clinical translational considerations of gut microbiota-bile acids-FXR in the treatment of the diseases.


Subject(s)
Bile Acids and Salts , Gastrointestinal Microbiome , Receptors, Cytoplasmic and Nuclear , Gastrointestinal Microbiome/physiology , Bile Acids and Salts/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , Humans , Animals , Metabolic Diseases/microbiology , Metabolic Diseases/metabolism , Liver/metabolism , Translational Research, Biomedical
15.
Genome Res ; 34(7): 981-996, 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39122473

ABSTRACT

Fish show variation in feeding habits to adapt to complex environments. However, the genetic basis of feeding preference and the corresponding metabolic strategies that differentiate feeding habits remain elusive. Here, by comparing the whole genome of a typical carnivorous fish (Leiocassis longirostris Günther) with that of herbivorous fish, we identify 250 genes through both positive selection and rapid evolution, including taste receptor taste receptor type 1 member 3 (tas1r3) and trypsin We demonstrate that tas1r3 is required for carnivore preference in tas1r3-deficient zebrafish and in a diet-shifted grass carp model. We confirm that trypsin correlates with the metabolic strategies of fish with distinct feeding habits. Furthermore, marked alterations in trypsin activity and metabolic profiles are accompanied by a transition of feeding preference in tas1r3-deficient zebrafish and diet-shifted grass carp. Our results reveal a conserved adaptation between feeding preference and corresponding metabolic strategies in fish, and provide novel insights into the adaptation of feeding habits over the evolution course.


Subject(s)
Genome , Receptors, G-Protein-Coupled , Zebrafish , Animals , Receptors, G-Protein-Coupled/genetics , Receptors, G-Protein-Coupled/metabolism , Zebrafish/genetics , Feeding Behavior , Carps/genetics , Carps/metabolism , Food Preferences , Carnivory , Evolution, Molecular
16.
J Chest Surg ; 2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39115201

ABSTRACT

Background: Torsion of the right middle lobe following right upper lobectomy is a rare but potentially fatal complication. To prevent this, fixation of the right middle lobe has been suggested. This study was performed to examine the impact of right middle lobe fixation on postoperative outcomes and bronchial changes. Methods: We enrolled patients who underwent curative-intent video-assisted thoracic surgery (VATS) right upper lobectomy for lung cancer from 2019 to 2022. Participants were grouped based on whether they did or did not receive right middle lobe fixation. Bronchial angles were measured using preoperative and postoperative chest computed tomography images, and postoperative outcomes and bronchial changes were compared between the 2 groups. Results: The study included a total of 50 patients, with 17 (34%) undergoing right middle lobe fixation. All procedures were performed using VATS. No significant differences between groups were observed in preoperative characteristics or postoperative outcomes. After surgery, both groups exhibited a significant increase in the right bronchus intermedius angle and a significant decrease in the branch angle. The postoperative right bronchus intermedius angle was significantly larger in the group without right middle lobe fixation compared to the group with fixation (47.38°±10.98° vs. 39.41°±9.21°, p=0.014). Three cases of atelectasis occurred in the group that did not undergo fixation while no cases were observed in the fixation group; however, this difference was not statistically significant. Conclusion: Fixation of the right middle lobe reduced postoperative angulation of the right bronchus intermedius, which may help prevent postoperative atelectasis.

17.
Sci Prog ; 107(3): 368504241263435, 2024.
Article in English | MEDLINE | ID: mdl-39096047

ABSTRACT

Water and foam have different fire-extinguishing mechanisms. Traditional foam and compressed air foam (CAF) have different bubble structures. These differences result in different thermal characteristics, which affect the extinguishing abilities during a fire. In this study, the differences in the thermal characteristics of three different extinguishing agents (water, traditional foam, and CAF) were investigated by suppressing a compartment fire. With an ignition source in the compartment (6 m × 3 m × 3 m), the agent was preferentially applied to the outside wall of the compartment. The effects of internal cooling and burnback resistance generated from the outer wall were evaluated. The performance of each agent in shielding firefighters from radiant heat while suppressing the fire inside the compartment was evaluated. When the outside wall of the compartment was covered with each of the agents, all agents were found to reduce the room temperature. When CAF was applied, the delay time until temperature re-rise was approximately 1.76-4.5 times longer than that when water was used. In addition, foaming agents exhibited a higher heat-shielding effect than water during the initial suppression. Thus, considering the thermal characteristics of these agents, fire suppression can be more effective if foam agents are used.

18.
Reg Anesth Pain Med ; 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38991713

ABSTRACT

BACKGROUND: This cadaveric study aimed to analyze injectate spread to target nerves during a single-injection, ultrasound-guided intertransverse process block. METHODS: An ultrasound-guided intertransverse process block with three different injectate volumes was administered to 12 cadavers. Each hemithorax was subjected to computer-generated random allocation of 10, 15, or 20 mL ultrasound-guided, single-injection intertransverse process block at the T2 vertebral level. Latex dye solution was injected into each hemithorax in accordance with the allocated volume. The presence of dye at the nerve root in the sympathetic chain and intercostal nerves at various injection levels was examined via dissection. RESULTS: Injectate spread into the dorsal rami was observed in seven of eight (87.5%), seven of eight (87.5%), and all eight (100%) of the 10, 15, and 20 mL specimens, respectively. In all 20 mL specimens, consistent staining of the dorsal rami, spinal nerve, and dorsal root ganglion was observed. CONCLUSIONS: An injectate volume of 20 mL was required for consistent staining of the dorsal rami, spinal nerve, and dorsal root ganglion in an intertransverse process block. Although an augmented injectate volume was associated with an increased likelihood of target nerve staining, consistent staining of the sympathetic ganglion, rami communicans, and ventral ramus was not observed, even at a volume of 20 mL. The current study presents initial findings suggesting that as opposed to a sympathetic ganglion block, a 20 mL intertransverse process block may act as a feasible substitute for dorsal root ganglion, spinal nerve, and medial branch blocks within a clinical context.

19.
Int J Sports Physiol Perform ; 19(9): 921-931, 2024 Sep 01.
Article in English | MEDLINE | ID: mdl-39043365

ABSTRACT

PURPOSE: Performing back squats with elastic bands has been widely used in resistance training. Although research demonstrated greater training effects obtained from adding elastic bands to the back squat, little is known regarding the optimal elastic resistance and how it affects neuromuscular performance. This study aimed to compare the force, velocity, power, and muscle activity during back squats with different contributions of elastic resistance. METHODS: Thirteen basketball players performed 3 repetitions of the back squat at 85% of 1-repetition maximum across 4 conditions: (1) total load from free weight and (2) 20%, (3) 30%, and (4) 40% of the total load from elastic band and the remaining load from free weight. The eccentric and concentric phases of the back squat were divided into upper, middle, and bottom phases. RESULTS: In the eccentric phase, mean velocity progressively increased with increasing elastic resistance, and muscle activity of the vastus medialis and rectus femoris significantly increased with the largest elastic resistance in the upper phase (P ≤ .036). In the concentric phase, mean power (P ≤ .021) and rate of force development (P ≤ .002) significantly increased with increasing elastic resistance. Furthermore, muscle activity of the vastus lateralis and vastus medialis significantly improved with the largest elastic resistance in the upper phases (P ≤ .021). CONCLUSION: Velocity, power, rate of force development, and selective muscle activity increased as the elastic resistance increased in different phases during the back-squat exercise.


Subject(s)
Basketball , Resistance Training , Humans , Resistance Training/methods , Biomechanical Phenomena , Male , Young Adult , Basketball/physiology , Muscle, Skeletal/physiology , Muscle Strength/physiology , Electromyography , Quadriceps Muscle/physiology , Kinetics
20.
Article in English | MEDLINE | ID: mdl-38963413

ABSTRACT

A Gram-stain-negative, yellow-pigmented, and facultatively aerobic bacterium, designated strain GPA1T, was isolated from plastic waste landfill soil in the Republic of Korea. The cells were non-motile short rods exhibiting oxidase-negative and catalase-positive activities. Growth was observed at 15-40 °C (optimum, 30 °C), at pH 6.0-9.0 (optimum, pH 7.0-8.0) and in the presence of 0-2.5 % (w/v) NaCl (optimum, 0 %). Menaquinone-7 was the sole respiratory quinone, and iso-C15 : 0, C16 : 1 ω5c, and iso-C17 : 0 3-OH were the major cellular fatty acids (>10 % of the total fatty acids). Phosphatidylethanolamine was identified as a major polar lipid. Phylogenetic analyses based on 16S rRNA gene sequences and 120 concatenated marker protein sequences revealed that strain GPA1T formed a distinct lineage within the genus Chitinophaga. The genome of strain GPA1T was 6078 kb in size with 53.8 mol% G+C content. Strain GPA1T exhibited the highest similarity to Chitinophaga rhizosphaerae T16R-86T, with a 98.6 % 16S rRNA gene sequence similarity, but their average nucleotide identity and digital DNA-DNA hybridization values were 82.5 and 25.9 %, respectively. Based on its phenotypic, chemotaxonomic, and phylogenetic characteristics, strain GPA1T represents a novel species of the genus Chitinophaga, for which the name Chitinophaga pollutisoli sp. nov. is proposed. The type strain is GPA1T (=KACC 23415T=JCM 36644T).


Subject(s)
Bacterial Typing Techniques , Bacteroidetes , Base Composition , DNA, Bacterial , Fatty Acids , Geologic Sediments , Phosphatidylethanolamines , Phylogeny , RNA, Ribosomal, 16S , Sequence Analysis, DNA , Soil Microbiology , Vitamin K 2 , RNA, Ribosomal, 16S/genetics , Republic of Korea , Fatty Acids/chemistry , Vitamin K 2/analogs & derivatives , Vitamin K 2/chemistry , Vitamin K 2/analysis , DNA, Bacterial/genetics , Geologic Sediments/microbiology , Bacteroidetes/isolation & purification , Bacteroidetes/classification , Bacteroidetes/genetics , Nucleic Acid Hybridization , Waste Disposal Facilities , Genome, Bacterial
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