Bacterial production of polyhydroxyalkanoates (PHAs) using various waste carbon sources
Synthetic plastics are in great demand in society due to their diversified properties, but they cause environmental pollution due to their non-biodegradable nature. Therefore, synthetic plastics are in need to be replaced with biodegradable plastics. Polyhydroxyalkanoates (PHAs), bacterial biopolymers are natural alternative to synthetic plastics. These are present inside the bacterial cytoplasm in granular form. Presently, the production cost of PHA is high due to expensive carbon substrates used in its biosynthesis. Therefore, this study focuses on the cost-effective production of PHA using waste carbon sources. Rice bran and sugarcane molasses were used as the carbon source for PHA production from Bacillus subtilis, Bacillus cereus, Alcaligenes sp. and Pseudomonas aeruginosa. PHA production from these bacterial strains was confirmed through Sudan Black-B screening. With rice bran, as carbon source, the highest PHA yield obtained was for P. aeruginosa, which yielded 93.7% and lowest was 35.5% for B. cereus. Surprisingly, B. cereus produced the highest cell dry mass (0.045 g/L) but its extracted PHA contents were lowest being only 0.02 g/L. Alcaligenes sp. with 0.031 g/L CDM yielded 87.1% PHA. B. subtilis had a CDM 0.029 g/L, 0.02 g/L PHA content and a yield of 69.10%. In the case of sugarcane molasses, P. aeruginosa produced 95% PHA yield, 0.02 g/L CDM, and 0.019 g/L PHA content. Alcaligenes sp. yielded 90.9% PHA, 0.011 g/L CDM, and 0.01 g/L PHA content. B. subtilis produced 91.6% PHA yield, 0.012 g/L CDM, 0.011 g/L PHA content; B. cereus produced 80% PHA yield, 0.015 g/L CDM, 0.012 g/L PHA content at 37 °C, pH 7. Higher concentrations of carbon sources increased the CDM and decreased the PHA yield. The maximum yield of PHA was obtained from sugarcane molasses. 24–48 h of incubation was optimal for B. subtilis and B. cereus, while for Alcaligenes and P. aeruginosa incubation time of 48–96 h was desirable for higher PHA yield. The extracted biopolymers were analyzed by Fourier transform infrared spectroscopy (FTIR), which identified the extracted biopolymers as poly-3-hydroxybutyrate P(3HB). The thermal properties of the extracted biopolymers, such as melting temperatures, were analyzed by differential scanning calorimetry (DSC), which confirmed the thermal stability.
Naseem et al. (2024) Bacterial production of polyhydroxyalkanoates (PHAs) using various waste carbon sources. PeerJ 12:e17936 https://doi.org/10.7717/peerj.17936
Is it worth the extra mile? Comparing environmental DNA and RNA metabarcoding for vertebrate and invertebrate biodiversity surveys in a lowland stream
Environmental DNA (eDNA) metabarcoding has emerged as a promising approach to assess biodiversity and derive ecological status classes from water samples. However, a limitation of eDNA surveys is that detected DNA molecules may originate from other places or even dead organisms, distorting local biodiversity assessments. Environmental RNA (eRNA) metabarcoding has recently been proposed as a complementary tool for more localized assessments of the biological community. In this study, we evaluated the effectiveness of eDNA and eRNA metabarcoding for inferring the richness and species distribution patterns of vertebrates and invertebrates in a Central European lowland river. We collected water samples and analyzed them using a 12S marker for vertebrates and a COI marker for invertebrates. We detected 31 fish, 16 mammal, 10 bird and one lamprey species in the vertebrate dataset. While results were largely consistent, we detected a higher number of species when analysing eRNA (mean = 30.89) than eDNA (mean = 26.16). Also, eRNA detections had a stronger local signature than eDNA detections when compared against species distribution patterns from traditional fish monitoring data. For invertebrates, we detected 109 arthropod, 22 annelid, 12 rotiferan, eight molluscan and four cnidarian species. In contrast to the pattern of vertebrate richness, we detected a higher richness using eDNA (mean = 41.37) compared to eRNA (mean = 22.42). Our findings primarily show that eDNA and eRNA-based detections are comparable for vertebrate and invertebrate taxa. Biological replication was important for both template molecules studied. Signal detections for vertebrates were more localized for eRNA compared to eDNA. Overall, the advantages of the extra steps needed for eRNA analyses depend on the study question but both methods provide important data for biodiversity monitoring and research.
Macher et al. (2024) Is it worth the extra mile? Comparing environmental DNA and RNA metabarcoding for vertebrate and invertebrate biodiversity surveys in a lowland stream. PeerJ 12:e18016 https://doi.org/10.7717/peerj.18016
Effect of acute anaerobic performance on zinc alpha 2 glycoprotein, apelin and lipasin levels
The aim of this study was to investigate the effects of acute anaerobic exercise on serum levels of adipokines Zinc-α2-glycoprotein (ZAG), apelin, and lipasin. Eighteen male athletes who actively played soccer and trained at least four days a week, with a mean age of 19.11 ± 2.59 years, body weight of 70.61 ± 8.17 kg, height of 176.0 ± 7.71 cm, sport age of 7.22 ± 2.60 years and BMI of 22.76 ± 1.68 kg/m2 participated in the study. Athletes were subjected to the Running-Based Anaerobic Sprint Test (RAST) for anaerobic performance. Blood samples were collected from the athletes 4 times (at rest, 10 minutes, 60 minutes, and 24 hours after exercise). The results of the study showed that acute anaerobic exercise significantly increased ZAG levels (p < 0.05). However, no statistically significant difference was detected in apelin and lipasin levels (p > 0.05). In conclusion, the findings of this study indicate that acute anaerobic exercise is associated with an increase in ZAG levels, but not apelin or lipasin levels. The observations suggest that ZAG may have a specific response to anaerobic exercise, which provides valuable insight into its potential impact on energy metabolism.
Ünver et al. (2024) Effect of acute anaerobic performance on zinc alpha 2 glycoprotein, apelin and lipasin levels. PeerJ 12:e18093 https://doi.org/10.7717/peerj.18093
Comparing efficacy in reducing pulling and welfare impacts of four types of leash walking equipment
Background Leash pulling is a commonly reported problem behavior for dog owners, as a result, a variety of leash equipment types are offered to mitigate pulling force. We were particularly interested in prong collars as their inherently aversive design has made their use a subject of debate. Though banned in certain countries and widely available in others, to date, there is no research comparing them to other leash walking equipment. Methods We compared four types of leash walking equipment: a martingale (flat collar as baseline measure), a front-connection harness, a polymer prong-style collar (Starmark), and a standard metal prong collar. Twenty-three dogs were walked on all four types of equipment for 5-min each. Equipment was attached to a leash which was connected to a battery-powered strain gauge to measure the dog’s pulling force. All walks were video recorded for behavior analysis. Results There were statistically significant differences among the leash equipment types in pulling impulse (Newtons × seconds), (χ2(2) = 30.6, p < 0.001). Post-hoc analysis revealed significant differences in impulse between the martingale and the other equipment: harness (Z = −3.69, p < 0.001), Starmark collar (Z = −3.62, p < 0.001) and prong collar (Z = −3.92, p < 0.001). No other differences among equipment types were significant. Fifteen behaviors were examined as welfare indicators but only three: looking at the handler, lip licking, and sniffing occurred across all dogs and all walks. There was a statistically significant difference in frequency of lip licking behavior across the four types of leash-equipment (χ2(2) = 8.17, p = 0.04) and post-hoc analysis showed a difference between the martingale and the harness (Z = −2.65, p = 0.008). While our research did not provide any clear evidence of poorer welfare due to equipment type, we caution the generalizability of these findings and recommend further assessment of these items of leash-walking equipment in real-life scenarios.
Johnson et al. (2024) Comparing efficacy in reducing pulling and welfare impacts of four types of leash walking equipment. PeerJ 12:e18131 https://doi.org/10.7717/peerj.18131
Evidence for sweep signatures in antibiotic-resistant strains in three species of bacteria
Over the last decades antibiotic resistance has evolved and spread in many different bacterial species. From an evolutionary perspective, drug resistance is an adaptation to a new environment. Population genetic theory predicts that recent adaptations are associated with reduced diversity in the part of the population that carries the adaptive trait, due to a process known as selective sweeps. It is not known if this prediction holds for antibiotic resistance in bacterial species that infect humans. Here, we use a convenience sample of eight datasets covering three species of bacteria (Escherichia coli, Staphylococcus aureus and Enterococcus faecium). The eight datasets include multi locus sequence type information and antibiotic resistance phenotypes for between 53 to 1,094 patient samples and between three and 19 different antibiotics. Consistent with selective sweep theory, we find that, in most cases, sequence-type diversity amongst antibiotic-resistant bacterial strains is lower than amongst antibiotic-susceptible strains. Specifically, in 45 out of 59 comparisons (76%), resistant strains were significantly less diverse than susceptible strains. We also observe that while diversity is lower amongst resistant strains, in all cases there were at least several different sequence types amongst the resistant strains, which suggests that we are dealing here with soft sweeps rather than hard sweeps. Finally, we show that sequence-type diversity of antibiotic-resistant strains is lower if resistance is rare, compared to when resistance is common, which is consistent with rare resistance being due to fewer evolutionary origins. To summarize, our results show that for several different bacterial species, diversity of resistant strains is generally reduced, which is consistent with the evolution of resistance driven by selective sweeps stemming from a limited number of evolutionary origins. In future studies, more detailed analysis of such sweep signatures is warranted.
Pradhananga et al. (2024) Evidence for sweep signatures in antibiotic-resistant strains in three species of bacteria. PeerJ 12:e18178 https://doi.org/10.7717/peerj.18178
Acute responses and recovery in the femoral cartilage morphology following running and cool-down protocols
This study compared the immediate effects of two common post-exercise cool-down methods to a control condition on subsequent morphologic change in femoral cartilage and vascular response in the posterior tibial artery after running. Sixteen healthy young males (23.6 ± 2.2 years, 172.8 ± 4.9 cm, 72.2 ± 7.1 kg) visited the laboratory during three separate sessions and performed 30-min of treadmill running (7.5 km/h for the initial 5-min, followed 8.5 km/h for 25-min). After running, participants experienced one of three 30-min cool-down protocols: active cool-down, cold application, or control (seated rest with their knee fully extended), in a counterbalanced order. Ultrasonographic assessments of femoral cartilage thickness (intercondylar, lateral, and medial) and posterior tibial artery blood flow were compared. To test condition effects over time, two-way analysis of variances and Tukey tests were used (p < 0.05) with Cohen’s d effect sizes (ES). There was no condition by time interaction in femoral cartilage thickness (intercondylar: F30,705 = 0.91, p = 0.61; lateral: F30,705 = 1.24, p = 0.18; medial: F30,705 = 0.49, p = 0.99). Regardless of time (condition effect: F2,705 > 3.24, p < 0.04 for all tests), femoral cartilage in the cold application condition was thicker than the control condition (intercondylar: p = 0.01, ES = 0.16; lateral: p < 0.0001, ES = 0.24; medial: p = 0.04. ES = 0.16). Regardless of condition (time effect: F15,705 > 10.31, p < 0.0001 for all tests), femoral cartilage thickness was decreased after running (intercondylar: p < 0.0001, ES = 1.37; lateral: p < 0.0001, ES = 1.58; medial: p < 0.0001, ES = 0.81) and returned to baseline levels within 40-min (intercondylar: p = 0.09; lateral: p = 0.64; medial: p = 0.26). Blood flow volume was different (condition × time: F30,705 = 2.36, p < 0.0001) that running-induced blood flow volume was maintained for 30-min for the active cool-down condition (p < 0.0001, ES = 1.64), whereas it returned to baseline levels within 10-min for other conditions (cold application: p = 0.67; control: p = 0.62). Neither blood flow nor temperature had a significant impact on the recovery in femoral cartilage after running.
Park et al. (2024) Acute responses and recovery in the femoral cartilage morphology following running and cool-down protocols. PeerJ 12:e18302 https://doi.org/10.7717/peerj.18302
Molecular detection of Batrachochytrium dendrobatidis (Chytridiomycota) and culturable skin bacteria associated with three critically endangered species of Atelopus (Anura: Bufonidae) in Ecuador
Chytridiomycosis is a fungal disease responsible for massive amphibian die-offs worldwide, caused by the fungus Batrachochytrium dendrobatidis (Bd). Potential symbiotic relationships between frogs and the bacteria residing on their skin—referred to as skin-bacteria—may inhibit Bd growth, aiding in resistance to this lethal disease. This research had three main objectives: (1) to detect the presence of Bd in native populations of Atelopus balios, A. bomolochos, and A. nanay in the central Andes and coastal southern regions of Ecuador; (2) to identify the culturable skin-bacteria; and (3) to analyze differences among the bacterial communities in the three Atelopus species studied. Skin swabs were collected from two populations of A. balios (107–203 m a.s.l.) and one population each of A. bomolochos and A. nanay (3,064–3,800 m a.s.l.). These swabs served two purposes: first, to detect Bd using conventional PCR; and second, to isolate culturable bacteria, which were characterized through DNA sequencing, molecular phylogeny, and community composition similarity analysis (Jaccard index). Results showed that Bd was present in all species, with positive Bd PCR amplification found in 11 of the 12 sampled amphibians. The culturable skin-bacteria were classified into 10 genera: Pseudomonas (31.4%), Stenotrophomonas (14.3%), Acinetobacter (11.4%), Serratia (11.4%), Aeromonas (5.7%), Brucella (5.7%), Klebsiella (5.7%), Microbacterium (5.7%), Rhodococcus (5.7%), and Lelliottia (2.9%). The Jaccard index revealed that bacterial genera were least similar in A. bomolochos and A. balios (J = 0.10), while the highest similarity at the genus level was between A. bomolochos and A. nanay (J = 0.33). At the clade-species level, only A. bomolochos and A. nanay show common bacteria (J = 0.13). Culturable bacterial communities of specimens diagnosed as Bd positive (n = 10) or Bd negative (n = 1) share a J value of 0.1 at genus and 0.04 at species-clade level. The prevalence of Bd and the composition of cutaneous bacteria could be influenced by Bd reservoirs, Atelopus biology, and intrinsic environmental conditions. This research contributes to understanding the relationship between endangered Andean species and Bd, and explores the potential use of native skin-bacteria as biocontrol agents against Bd.
Yánez Galarza et al. (2024) Molecular detection of Batrachochytrium dendrobatidis (Chytridiomycota) and culturable skin bacteria associated with three critically endangered species of Atelopus (Anura: Bufonidae) in Ecuador. PeerJ 12:e18317 https://doi.org/10.7717/peerj.18317
Cross-cultural adaptation and psychometric validation of a Chinese self-intermittent catheterization quality of life scale among patients with neurogenic bladder
Background Intermittent self-catheterization (ISC) is widely considered the gold standard for treating patients with neurogenic bladder (NB). Healthcare professionals and catheter users must optimize ISC care to improve patients’ quality of life. To achieve this, the Intermittent Self-Catheterization Questionnaire (ISC-Q) is a valuable tool with clear and easy-to-understand items. However, this scale has yet to be adapted for use in China, and its reliability and validity need to be tested through cross-cultural adaptation. Objectives The objective of this study was to culturally adapt the ISC-Q and develop the Chinese version of the ISC-Q (C-ISC-Q), and assess its reliability and validity among patients with NB. Methods With the authorization of the ISC-Q author, the Beaton mode was used to adapt the scale cross-culturally. The study was conducted from June 2020 to June 2021 in three phases: committee-based translation from English to Chinese, Delphi expert consultations (n = 5) for cultural adaptation, and a cross-sectional study (n = 149) for validation. Results The C-ISC-Q has 24 items and four dimensions. The critical ratio of each item is over 3.0, and the correlation coefficient between each item and the scale’s total score is above 0.4. The Cronbach’s α value for the scale is 0.930, and for each dimension, it is between 0.870–0.92. The retest reliability for the scale is 0.894, and for each dimension is between 0.751–0.889. The content validity at the item level ranges from 0.8~1.0, and at the scale level is 0.9. The criterion-related validity of the scale was −0.708, and the correlation for each dimension was 0.329–0.624. The principal component analysis identified four common factors, with a cumulative contribution rate of 67.846%. Conclusions The C-ISC-Q is culturally sensitive, reliable, and valid to measure the quality of life for patients with NB. It can assist nurses and researchers in tailoring strategies to enhance the quality of life for patients with NB.
Tang et al. (2024) Cross-cultural adaptation and psychometric validation of a Chinese self-intermittent catheterization quality of life scale among patients with neurogenic bladder. PeerJ 12:e18319 https://doi.org/10.7717/peerj.18319
Association analysis of MTHFR (rs1801133 and rs1801131) gene polymorphism towards the development of type 2 diabetes mellitus in Dali area population from Yunnan Province, China
Background Type 2 diabetes mellitus (T2DM) is a common complex metabolic disorder that exhibits a strong genetic predisposition. 5,10-methylenetetrahydrofolate reductase (MTHFR) regulates folate metabolism, which has been proposed to be associated with T2DM, although the relationship is inconsistent among different geographical areas. This study aimed to investigate the effects of MTHFR C677T (rs1801133) and A1298C (rs1801131) loci polymorphisms on T2DM susceptibility in the population of the Dali area in Yunnan Province, China. Methods This case-control study included 445 patients with T2DM and 272 healthy control individuals from the Dali area of Yunnan Province. Genotyping of the MTHFR gene polymorphisms was performed using the competitive allele-specific PCR (KASP) method. The effects of genetic variations of the MTHFR gene on T2DM risk were evaluated using odds ratios (OR) and 95% confidence intervals. Results The results of the present study revealed that the TT genotype (OR = 1.750, P = 0.030) and the T allele (OR = 1.252, P = 0.047) at the MTHFR C677T locus were considerably associated with the increased odds of developing T2DM. In addition, the CC genotype (OR = 3.132, P = 0.032) at the MTHFR A1298C locus also substantially increased the odds of developing T2DM. The T-A haplotype (OR = 1.305, P = 0.030) of MTHFR C677T and A1298C exhibited the increased odds of developing T2DM. Biochemical index analyses showed that patients with T2DM who carried the CT or TT genotype of MTHFR C677T expressed substantially higher levels of fasting blood glucose (FBG), homocysteine (Hcy), and tumor necrosis factor-alpha (TNF-α) than those of the CC genotype. Moreover, the FBG and Hcy levels were considerably higher in patients with T2DM who carried the CC or AC genotype of MTHFR A1298C than those of the AA genotype. No obvious association was observed between these MTHFR polymorphisms and cardiovascular risk in T2DM. Conclusion Our study suggests that the genetic variations of MTHFR C677T and A1298C are significantly associated with T2DM susceptibility in the population of the Dali area of Yunnan Province, China.
Liu et al. (2024) Association analysis of MTHFR (rs1801133 and rs1801131) gene polymorphism towards the development of type 2 diabetes mellitus in Dali area population from Yunnan Province, China. PeerJ 12:e18334 https://doi.org/10.7717/peerj.18334
Remote care instruction via the WeChat platform for female patients receiving subcutaneous anticoagulation during the COVID-19 pandemic: a retrospective analysis
Background The purpose of this study was to estimate the effect of remote nursing guidance based on WeChat platform for female patients receiving subcutaneous anticoagulation during the COVID-19 epidemic. Methods Retrospective analysis of clinical data, including demographic data and anticoagulation complications, of 126 female patients who received subcutaneous anticoagulation therapy and received remote nursing guidance using WeChat platform in our hospital from January 2022 to December 2022. The Anti-Clot Treatment Scale (ACTS) and the World Health Organization Quality of Life-BREF (WHOQOL-BREF) scale were used to evaluate patients’ satisfaction with anticoagulation and quality of life at the beginning of anticoagulation, half a month after anticoagulation, and after three months of anticoagulation. Results In total, 126 patients were involved in this study, all of them were female, 115 cases were natural pregnancy, 11 cases were assisted reproduction. This study included seven cases of lower extremity deep vein thrombosis, 100 cases of hypercoagulable state, 10 cases of antiphospholipid syndrome, and eight cases of protein S deficiency, one case of hyperhomocysteinemia. During the follow-up period, four patients (3.17%) had subcutaneous injection complications, including three cases of subcutaneous hemorrhage and one case of liquid leakage. A total of 123 patients had completed the planned anticoagulation therapy or were receiving anticoagulation therapy as planned, and three patients did not receive anticoagulation therapy as planned (zero cases lost contact, two cases changed treatment units, and one case refused treatment). ACTS score (55.03 ± 1.73) and WHOQOL-BREF score (62.18 ± 3.17) after three months of anticoagulation, ACTS score (54.18 ± 1.20) and WHOQOL-BREF score (60.37 ± 2.25) after half a month of anticoagulation was significantly higher than the ACTS score (47.81 ± 1.69) and WHOQOL-BREF score (55.25 ± 1.85) at the beginning of anticoagulation, and the difference was statistically significant (P value < 0.01). Conclusions During the COVID-19 pandemic, remote nursing instruction via the WeChat platform for female patients receiving subcutaneous anticoagulation can increase anticoagulation compliance, satisfaction, and quality of life.
Jiang et al. (2024) Remote care instruction via the WeChat platform for female patients receiving subcutaneous anticoagulation during the COVID-19 pandemic: a retrospective analysis. PeerJ 12:e18337 https://doi.org/10.7717/peerj.18337