title: PeerJ description: Articles published in PeerJ link: https://peerj.com/articles/index.rss3?journal=peerj&page=996 creator: info@peerj.com PeerJ errorsTo: info@peerj.com PeerJ language: en title: Assessment of the effects of ischaemia/ hypoxia on angiogenesis in rat myofascial trigger points using colour Doppler flow imaging link: https://peerj.com/articles/10481 last-modified: 2020-12-09 description: Background & AimsMyofascial pain syndrome (MPS) is a common non-articular disorder of the musculoskeletal system that is characterized by the presence of myofascial trigger points (MTrPs). Despite the high prevalence of MPS, its pathogenesis, which induces the onset and maintenance of MTrPs, is still not completely understood. To date, no studies have investigated the changes in the biochemical milieu caused by ischaemia/hypoxia in the MTrP regions of muscle that are proposed in the integrated hypothesis. Therefore, this study investigated whether ischaemic/hypoxic conditions participate in the formation of active MTrPs and affect angiogenesis using colour Doppler flow imaging (CDFI).MethodsTwenty-five Sprague-Dawley rats were randomly divided into a model group and a normal control group. A model of active MTrPs was established by a blunt strike combined with eccentric exercise. Enzyme-linked immunosorbent assays (ELISAs) were employed to detect the levels of HIF-1α and VEGF. Microvessel density (MVD) was evaluated using immunohistochemistry. CDFI was applied to observe the blood flow signals in the MTrPs, which were classified into four grades based on their strengths.ResultsCompared with the control group, the active MTrP group exhibited significantly higher HIF-1α and VEGF levels and MVD values. These differences were accompanied by increased blood flow signals. In the active MTrP group, the blood flow signal grade was positively correlated with the MVD (P < 0.05) and independently correlated with the VEGF level (P < 0.05) but was not correlated with the expression of HIF-1α (P > 0.05).ConclusionIschaemic/hypoxic conditions may be involved in the formation of MTrPs. CDFI is useful for detection of the features of angiogenesis in or surrounding MTrPs via assessment of blood flow signals. creator: Fangyan Jiang creator: Shuangcheng Yu creator: Haiqing Su creator: Shangyong Zhu uri: https://doi.org/10.7717/peerj.10481 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Jiang et al. title: Oncolytic effects of the recombinant Newcastle disease virus, rAF-IL12, against colon cancer cells in vitro and in tumor-challenged NCr-Foxn1nu nude mice link: https://peerj.com/articles/9761 last-modified: 2020-12-08 description: Colon cancer remains one of the main cancers causing death in men and women worldwide as certain colon cancer subtypes are resistant to conventional treatments and the development of new cancer therapies remains elusive. Alternative modalities such as the use of viral-based therapeutic cancer vaccine is still limited, with only the herpes simplex virus (HSV) expressing granulocyte-macrophage colony- stimulating factor (GM-CSF) or talimogene laherparepvec (T-Vec) being approved in the USA and Europe so far. Therefore, it is imperative to continue the search for a new treatment modality. This current study evaluates a combinatorial therapy between the oncolytic Newcastle disease virus (NDV) and interleukin-12 (IL-12) cytokine as a potential therapeutic vaccine to the current anti-cancer drugs. Several in vitro analyses such as MTT assay, Annexin V/FITC flow cytometry, and cell cycle assay were performed to evaluate the cytotoxicity effect of recombinant NDV, rAF-IL12. Meanwhile, serum cytokine, serum biochemical, histopathology of organs and TUNEL assay were carried out to assess the anti-tumoral effects of rAF-IL12 in HT29 tumor-challenged nude mice. The apoptosis mechanism underlying the effect of rAF-IL12 treatment was also investigated using NanoString Gene expression analysis. The recombinant NDV, rAF-IL12 replicated in HT29 colon cancer cells as did its parental virus, AF2240-i. The rAF-IL12 treatment had slightly better cytotoxicity effects towards HT29 cancer cells when compared to the AF2240-i as revealed by the MTT, Annexin V FITC and cell cycle assay. Meanwhile, the 28-day treatment with rAF-IL12 had significantly (p < 0.05) perturbed the growth and progression of HT29 tumor in NCr-Foxn1nu nude mice when compared to the untreated and parental wild-type NDV strain AF2240-i. The rAF-IL12 also modulated the immune system in nude mice by significantly (p < 0.05) increased the level of IL-2, IL-12, and IFN-γ cytokines. Treatment with rAF-IL12 had also significantly (p < 0.05) increased the expression level of apoptosis-related genes such as Fas, caspase-8, BID, BAX, Smad3 and granzyme B in vitro and in vivo. Besides, rAF-IL12 intra-tumoral delivery was considered safe and was not hazardous to the host as evidenced in pathophysiology of the normal tissues and organs of the mice as well as from the serum biochemistry profile of liver and kidney. Therefore, this study proves that rAF-IL12 had better cytotoxicity effects than its parental AF2240-i and could potentially be an ideal treatment for colon cancer in the near future. creator: Syed Umar Faruq Syed Najmuddin creator: Zahiah Mohamed Amin creator: Sheau Wei Tan creator: Swee Keong Yeap creator: Jeevanathan Kalyanasundram creator: Abhimanyu Veerakumarasivam creator: Soon Choy Chan creator: Suet Lin Chia creator: Khatijah Yusoff creator: Noorjahan Banu Alitheen uri: https://doi.org/10.7717/peerj.9761 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2020 Syed Najmuddin et al. title: Characterization of sediment microbial communities at two sites with low hydrocarbon pollution in the southeast Gulf of Mexico link: https://peerj.com/articles/10339 last-modified: 2020-12-08 description: BackgroundCoastal ecosystems are prone to hydrocarbon pollution due to human activities, and this issue has a tremendous impact on the environment, socioeconomic consequences, and represents a hazard to humans. Bioremediation relies on the ability of bacteria to metabolize hydrocarbons with the aim of cleaning up polluted sites.MethodsThe potential of naturally occurring microbial communities as oil degraders was investigated in Sisal and Progreso, two port locations in the southeast Gulf of Mexico, both with a low level of hydrocarbon pollution. To do so, we determined the diversity and composition of bacterial communities in the marine sediment during the dry and rainy seasons using 16S rRNA sequencing. Functional profile analysis (PICRUTSt2) was used to predict metabolic functions associated with hydrocarbon degradation.ResultsWe found a large bacterial taxonomic diversity, including some genera reported as hydrocarbon-degraders. Analyses of the alpha and beta diversity did not detect significant differences between sites or seasons, suggesting that location, season, and the contamination level detected here do not represent determining factors in the structure of the microbial communities. PICRUTSt2 predicted 10 metabolic functions associated with hydrocarbon degradation. Most bacterial genera with potential hydrocarbon bioremediation activity were generalists likely capable of degrading different hydrocarbon compounds. The bacterial composition and diversity reported here represent an initial attempt to characterize sites with low levels of contamination. This information is crucial for understanding the impact of eventual rises in hydrocarbon pollution. creator: Pablo Suárez-Moo creator: Araceli Lamelas creator: Itza Garcia-Bautista creator: Luis Felipe Barahona-Pérez creator: Gloria Sandoval-Flores creator: David Valdes-Lozano creator: Tanit Toledano-Thompson creator: Erik Polanco-Lugo creator: Ruby Valdez-Ojeda uri: https://doi.org/10.7717/peerj.10339 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Suárez-Moo et al. title: Insights into dog owner perspectives on risks, benefits, and nutritional value of raw diets compared to commercial cooked diets link: https://peerj.com/articles/10383 last-modified: 2020-12-08 description: BackgroundThe practice of feeding a raw meat-based diet (RMBD) to dogs is a topic of increasing interest to owners and veterinary professionals alike. Despite the research around the practice, particularly about the risk of nutritional imbalances and microbial contamination, an increasing number of dog owners are adopting a raw diet for their dogs. This study expands the research into owner motivations for feeding RMBDs and cooked diets and asks them their opinions about risk and nutritional value.MethodsAn anonymized, online, internationally accessible questionnaire was developed to ascertain owner perspectives on the risks, benefits, and nutritional value of commercially prepared and homemade RMBDs as compared with commercially prepared cooked diets (CCDs).ResultsThe questionnaire was completed by 419 dog owners of diverse backgrounds across the world. Of the participants, 25.3% fed RMBDs. Just over 70.0% of all participants had spoken to their veterinarian about their dog’s nutrition. Owners who fed RMBDs ranked their veterinarian’s knowledge lower and their own knowledge of canine nutrition higher than owners who fed CCDs. They rated commercial and homemade RMBDs as highly nutritious 83.5% and 73.6% of the time, respectively, while only 12.5% rated CCDs as highly nutritious. Owners who fed CCDs ranked RMBDs as highly nutritious less often, but also only ranked CCDs as highly nutritious 52.7% of the time. All participants agreed that CCDs were low risk to human health. Owners who fed RMBDs ranked raw diets as highly risky to human or dog health under 20.0% of the time but deemed CCDs risky to animal health over 65.0% of the time. When asked about benefits of raw diets, the most repeated words offered by owners were “health”, “better”, “coat” and “teeth”. The most repeated risks presented were “bacteria”, “nutrition”, “risk” and “Salmonella”. Owners who fed RMBDs tended to use vague terminology like “health” and “better” when asked why they fed a raw diet. Owners who did not feed RMBDs used more specific terminology like “expensive”, “time” and “risk” when asked why they did not feed a raw diet. Overall, the two groups differed in their perceptions around RMBD and CCD feeding, which highlights the need for a better line of communication and education between veterinarians and owners. creator: Alysia Empert-Gallegos creator: Sally Hill creator: Philippa S. Yam uri: https://doi.org/10.7717/peerj.10383 license: https://creativecommons.org/licenses/by/4.0/ rights: © 2020 Empert-Gallegos et al. title: Polo like kinase 1 expression in cervical cancer tissues generated from multiple detection methods link: https://peerj.com/articles/10458 last-modified: 2020-12-08 description: BackgroundExisting studies of PLK1 in cervical cancer had several flaws. The methods adopted by those studies of detecting PLK1 expression in cervical cancer were single and there lacks comprehensive evaluation of the clinico-pathological significance of PLK1 in cervical cancer.MethodsA total of 303 cervical tissue samples were collected for in-house tissue microarrays. Immunohistochemistry was performed for evaluating PLK1 expression between cervical cancer (including cervical squamous cell carcinoma (CESC) and cervical adenocarcinoma) and non-cancer samples. The Expression Atlas database was searched for querying PLK1 expression in different cervical cancer cell lines and different tissues in the context of pan-cancer. Standard mean difference (SMD) was calculated and the summarized receiver’s operating characteristics (SROC) curves were plotted for integrated tissue microarrays, exterior high-throughput microarrays and RNA sequencing data as further verification. The effect of PLK1 expression on the overall survival, disease-free survival and event-free survival of cervical cancer patients was analyzed through Kaplan Meier survival curves for cervical cancer patients from RNA-seq and GSE44001 datasets. The gene mutation and alteration status of PLK1 in cervical cancer was inspected in COSMIC and cBioPortal databases. Functional enrichment analysis was performed for genes correlated with PLK1 from aggregated RNA-seq and microarrays.ResultsA total of 963 cervical cancer samples and 178 non-cancer samples were collected from in-house tissue microarrays and exterior microarrays and RNA-seq datasets. The combined expression analysis supported overexpression of PLK1 in CESC, cervical adenocarcinoma and all types of cervical cancer (SMD = 1.59, 95%CI [0.56–2.63]; SMD = 2.99, 95%CI [0.75–5.24]; SMD = 1.57, 95% CI [0.85–2.29]) and the significant power of PLK1 expression in distinguishing CESC or all types of cervical cancer samples from non-cancer samples (AUC = 0.94, AUC = 0.92). Kaplan-Meier survival curves showed that the event-free survival rate of cervical cancer patients with higher expression of PLK1 was shorter than that of patients with lower PLK1 (HR = 2.020, P = 0.0197). Genetic alteration of PLK1 including missense mutation and mRNA low occurred in 6% of cervical cancer samples profiled in mRNA expression. Genes positively or negatively correlated with PLK1 were mainly assembled in pathways such as DNA replication, cell cycle, mismatch repair, Ras signaling pathway, melanoma, EGFR tyrosine kinase inhibitor resistance and homologous recombination (P < 0.05).ConclusionsHere, we provided sufficient evidence of PLK1 overexpression in cervical cancer. The overexpression of PLK1 in cervical cancer and the contributory effect of it on clinical progression indicated the hopeful prospect of PLK1 as a biomarker for cervical cancer. creator: Li Gao creator: Yu-Yan Pang creator: Xian-Yu Guo creator: Jing-Jing Zeng creator: Zhong-Qing Tang creator: Dan-Dan Xiong creator: Xia Yang creator: Ying Li creator: Fu-Chao Ma creator: Lin-Jiang Pan creator: Zhen-Bo Feng creator: Gang Chen uri: https://doi.org/10.7717/peerj.10458 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Gao et al. title: Genetic diversity and population structure of eddoe taro in China using genome-wide SNP markers link: https://peerj.com/articles/10485 last-modified: 2020-12-08 description: Taro (Colocasia esculenta) is an important root and tuber crop cultivated worldwide. There are two main types of taro that vary in morphology of corm and cormel, ‘dasheen’ and ‘eddoe’. The eddoe type (Colocasia esculenta var. antiquorium) is predominantly distributed throughout China. Characterizing the genetic diversity present in the germplasm bank of taro is fundamental to better manage, conserve and utilize the genetic resources of this species. In this study, the genetic diversity of 234 taro accessions from 16 provinces of China was assessed using 132,869 single nucleotide polymorphism (SNP) markers identified by specific length amplified fragment-sequencing (SLAF-seq). Population structure and principal component analysis permitted the accessions to be categorized into eight groups. The genetic diversity and population differentiation of the eight groups were evaluated using the characterized SNPs. Analysis of molecular variance showed that the variation among eight inferred groups was higher than that within groups, while a relatively small variance was found among the two morphological types and 16 collection regions. Further, a core germplasm set comprising 41 taro accessions that maintained the genetic diversity of the entire collection was developed based on the genotype. This research is expected to be valuable for genetic characterization, germplasm conservation, and breeding of taro. creator: Zhixin Wang creator: Yalin Sun creator: Xinfang Huang creator: Feng Li creator: Yuping Liu creator: Honglian Zhu creator: Zhengwei Liu creator: Weidong Ke uri: https://doi.org/10.7717/peerj.10485 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Wang et al. title: Effects of auxin (indole-3-butyric acid) on growth characteristics, lignification, and expression profiles of genes involved in lignin biosynthesis in carrot taproot link: https://peerj.com/articles/10492 last-modified: 2020-12-08 description: Carrot is an important root vegetable crop abundant in bioactive compounds including carotenoids, vitamins, and dietary fibers. Carrot intake and its products are gradually growing owing to its high antioxidant activity. Auxins are a class of plant hormones that control many processes of plant growth and development. Yet, the effects of exogenous application of auxin on lignin biosynthesis and gene expression profiles of lignin-related genes in carrot taproot are still unclear. In order to investigate the effect of exogenous indole-3-butyric acid (IBA) on lignin-related gene profiles, lignin accumulation, anatomical structures and morphological characteristics in carrot taproots, carrots were treated with different concentrations of IBA (0, 50, 100, and 150 µM). The results showed that IBA application significantly improved the growth parameters of carrot. The 100 or 150 µM IBA treatment increased the number and area of xylem vessels, whereas transcript levels of lignin-related genes were restricted, resulting in a decline in lignin content in carrot taproots. The results indicate that taproot development and lignin accumulation may be influenced by the auxin levels within carrot plants. creator: Ahmed Khadr creator: Guang-Long Wang creator: Ya-Hui Wang creator: Rong-Rong Zhang creator: Xin-Rui Wang creator: Zhi-Sheng Xu creator: Yong-Sheng Tian creator: Ai-Sheng Xiong uri: https://doi.org/10.7717/peerj.10492 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Khadr et al. title: Density-dependent condition of juvenile penaeid shrimps in seagrass-dominated aquatic vegetation beds located at different distance from a tidal inlet link: https://peerj.com/articles/10496 last-modified: 2020-12-08 description: Seagrasses are critical habitats for the recruitment and growth of juvenile penaeid shrimps within estuaries and coastal lagoons. The location of a seagrass bed within the lagoon can determine the value of a particular bed for shrimp populations. Consequently, differences in the abundance of shrimp can be found in seagrasses depending on their location. As shrimp density increases, density-dependent effects on biological parameters are more likely to occur. However, knowledge about density-dependent processes on shrimp populations in nursery habitats remains limited. The present investigation was undertaken to examine the effects of population density on shrimp condition in two selected seagrass beds, located at different distance from a tidal inlet, one 25 km away (distant) and the other 1 km away (nearby), in a subtropical coastal lagoon. The study was based on monthly samplings during one year in Laguna Madre (Mexico), performing a total of 36 shrimp trawls (100 m2 each one) within each seagrass bed (n = 3 trawls per bed per month for 12 months). Shrimp density was related to the proximity to the tidal inlet (higher density was consistently observed in the nearby seagrass bed), which in turn adversely affected the condition of both species studied (Penaeus aztecus and P. duorarum). In this regard, the present study provides the first evidence of density-dependent effects on shrimp condition inhabiting a nursery habitat. Both shrimp species exhibited a negative relationship between condition and shrimp density. However, this pattern differed depending on the proximity to the tidal inlet, suggesting that shrimp populations inhabiting the nearby seagrass bed are exposed to density-dependent effects on condition; whereas, such effects were not detected in the distant seagrass bed. Shrimp density within the distant seagrass bed was probably below carrying capacity, which is suggested by the better shrimp condition observed in that area of the lagoon. Intra and interspecific competition for food items is surmised to occur, predominantly within seagrass beds near the tidal inlet. However, this hypothesis needs to be tested in future studies. creator: Zeferino Blanco-Martínez creator: Roberto Pérez-Castañeda creator: Jesús Genaro Sánchez-Martínez creator: Flaviano Benavides-González creator: Jaime Luis Rábago-Castro creator: María de la Luz Vázquez-Sauceda creator: Lorena Garrido-Olvera uri: https://doi.org/10.7717/peerj.10496 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Blanco-Martínez et al. title: Pro-inflammatory effect of obesity on rats with burn wounds link: https://peerj.com/articles/10499 last-modified: 2020-12-08 description: ObjectiveA burn is an inflammatory injury to the skin or other tissue due to contact with thermal, radioactive, electric, or chemical agents. Burn injury is an important cause of disability and death worldwide. Obesity is a significant public health problem, often causing underlying systemic inflammation. Studying the combined impact of burn injuries on obese patients has become critical to the successful treatment of these patients. The aim of this paper is to highlight the effect of inflammation associated with burn injuries on several body weight group in a rat study.Materials and methodsDifferent degrees of obesity and burns were established in rats and divided into a normal weight group, overweight group, obese group, second-degree burn group, third-degree burn group, over-weight second-degree burn group, over-weight third-degree burn group, obese second-degree burn group, and obese third-degree burn group (20 rats per group). Changes in inflammatory factors and growth factor were measured on the 1st, 3rd, 7th and 14th days after burns were inflicted.ResultsThe ELISA test showed that in the unburned control group, MCP-1, IL-1β and TNF-α protein expressions in the obese and over-weight groups were higher than the normal-weight group (P < 0.05). RT-PCR test showed that the expressions of MCP-1, IL-1β and TNF-α genes in the obese group were higher compared to the overweight and normal weight groups (P < 0.05). Three and 7 days after burns were inflicted, the level of VEGF in the normal weight group was higher than the obese group (P < 0.05), however increased VEGF was not observed on days 1 and 14.ConclusionBurn injury and obesity have a mutually synergistic effect on the body’s inflammatory response. creator: Chan Nie creator: Huiting Yu creator: Xue Wang creator: Xiahong Li creator: Zairong Wei creator: Xiuquan Shi uri: https://doi.org/10.7717/peerj.10499 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Nie et al. title: Self-reports vs. physical measures of spinal stiffness link: https://peerj.com/articles/9598 last-modified: 2020-12-07 description: BackgroundObjectively measured reduction in lumbar posterior-to-anterior (PA) stiffness is associated with pain relief in some, but not all persons with low back pain. Unfortunately, these measurements can be time consuming to perform. In comparison, the Lumbar Spine Instability Questionnaire (LSIQ) is intended to measure spinal instability and the Lumbar Spine Disability Index (LSDI) is created for self-reporting functional disability due to increased spinal stiffness. Given the above, the aim of this study is to compare measures of the LSIQ and LSDI with objective measures of lumbar PA stiffness as measured by a mechanical device, Vertetrack (VT), in patients with persistent non-specific low back pain (nsLBP).MethodsTwenty-nine patients with nsLBP completed the LSIQ and LSDI at baseline and after two weeks. On these same occasions, PA spinal stiffness was measured using the VT. Between measurements, patients received four sessions of spinal manipulation. The resulting data was analyzed to determine the correlation between the self-report and objective measures of stiffness at both time points. Further, the patients were categorized into responders and non-responders based on pre-established cut points depending on values from the VT and compared those to self-report measures in order to determine whether the LSIQ and the LSDI were sensitive to change.ResultsTwenty-nine participants completed the study. Measures from the LSIQ and LSDI correlated poorly with objectively measured lumbar PA stiffness at baseline and also with the change scores. The change in objectively measured lumbar PA stiffness following spinal manipulation did not differ between those who improved, and those who did not improve according to the pre-specified cut-points. Finally, a reduction in lumbar PA stiffness following intervention was not associated with improvement in LSIQ and LSDI outcomes.ConclusionsThe current data indicate that the LSIQ and LSDI questionnaires do not correlate with measures obtained objectively by VT. Our results suggest that these objective and self- reported measures represent different domains and as such, cannot stand in place of one another. creator: Jonas Nielsen creator: Casper Glissmann Nim creator: Søren O’Neill creator: Eleanor Boyle creator: Jan Hartvigsen creator: Gregory N. Kawchuk uri: https://doi.org/10.7717/peerj.9598 license: https://creativecommons.org/licenses/by/4.0/ rights: ©2020 Nielsen et al.