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Haozhi Long

and 8 more

This study aimed to research the effects of forest (Pinus elliottii, slash pine) and shrub (Vitex trifolia) plantation on the soil microbial community in sandification land by using the Illumina Miseq sequencing of 16S rRNA and ITS rRNA genes and combined with the soil properties analysis to explore the driving factors. Finally, the results showed that the dominant bacterial phylum was Chloroflexi, Actinobacteria, Proteobacteria, and Acidobacteria, the shrub and forest plantation significantly increasing the proportion of Acidobacteria, while decreasing the proportion of Proteobacteria. For the fungal community, forest plantation was significantly changing the community structure at the phylum level that shifted from Ascomycota to Basidiomycota, and the ectomycorrhizal fungi take the most abundant with genus Rhizopogon predominant. The soil bacterial Chao1 and Shannon indices were significantly increased after revegetation, while the soil fungal Shannon diversity in the forest land that significantly correlated with soil total organic carbon and C/N was lower than that in the sandy and shrub land (p<0.05). Besides, the bacterial and fungal communities were significantly affected by soil water content among all analyzed soil properties. Our results suggest that the revegetation significantly increasing the soil bacterial diversity that correlated with soil water content, total organic carbon, and available phosphorus, but there was no significant change in community structure. In contrast, slash pine plantation changes the fungal community structure and diversity dramatically, and such changes should be attention because the shift of fungi community structure and diversity may lead to the decline of Pinaceae plantation.

Okhee Choi

and 4 more

Carotenoids are widely used in functional foods, cosmetics, and health supplements, and their importance and scope of use are continuously expanding. Here, we characterised carotenoid biosynthetic genes of the plant-pathogenic bacterium Pantoea ananatis, which carries a carotenoid biosynthetic gene cluster (including crtE, X, Y, I, B, and Z) on a plasmid. Reverse transcription–polymerase chain reaction (RT-PCR) analysis revealed that the crtEXYIB gene cluster is transcribed as a single transcript and crtZ is independently transcribed in the opposite direction. Using splicing by overlap extension with polymerase chain reaction (SOE by PCR) based on asymmetric amplification, we reassembled crtE–B, crtE–B–I, and crtE–B–I–Y. High-performance liquid chromatography confirmed that Escherichia coli expressing the reassembled crtE–B, crtE–B–I, and crtE–B–I–Y operons produced phytoene, lycopene, and β-carotene, respectively. We found that the carotenoids conferred tolerance to UV radiation and toxoflavin. Pantoea ananatis shares rice environments with the toxoflavin producer Burkholderia glumae and is considered to be the first reported example of producing and using carotenoids to withstand toxoflavin. We confirmed that the carotenoid production of P. ananatis is dependent on RpoS, which is positively regulated by Hfq/ArcZ and negatively regulated by ClpP, similar to an important regulatory network of E. coli (HfqArcZ → RpoS Ͱ ClpXP). We also demonstrated that Hfq-controlled quorum signalling de-represses EanR to activate RpoS, thereby initiating carotenoid production. Survival genes such as those responsible for the production of carotenoids of the plant-pathogenic P. ananatis must be expressed in a timely manner to overcome stressful environments and compete with other microorganisms. This mechanism is likely maintained by a brake with excellent performance, such as EanR.

Chao Li

and 8 more

Peng Peng

and 8 more

Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a newly identified swine enteropathogenic coronavirus that causes watery diarrhea in neonatal piglets, leading to significant economic losses to the swine industry. Currently there are no suitable serological method to assess the infection of SADV-CoV and effectiveness of vaccines, making an urgent need to exploit effect enzyme-linked immunosorbent assay (ELISA) to compensate for this deficiency. In this study, an indirect ELISA (S-iELISA) based on recombinant spike (S) protein expressed in Baculovirus was developed and evaluated. The reaction conditions of S-iELISA were optimized and cut-off value determined as 0.3711 by analyzing OD450nm values of 40 SADS-CoV-negative sera confirmed by immunoinfluscent assay (IFA) and Western Blot. The coefficients of variation of 6 positive sera within and between runs of S-iELISA were both less than 10% and cross-reactivity assays demonstrated that S-iELISA was non-cross-reactive with other swine viruses’ sera. Furthermore, the overall coincidence rate between IFA and S-iELISA was 97.3% based on testing 111 clinical serum samples. Virus neutralization test with 7 different OD450nm value sera showed that the OD450nm values tested by S-iELISA are positive correlated with virus neutralization. Finally, a total of 300 pig field serum samples were tested by S-iELISA and commercial kits of other swine enteroviruses showed that the IgG-positive for SADS-CoV, TGEV, PDCoV and PEDV were 81.7%, 54%, 65.3%, 6%, respectively. The results suggest this S-iELISA is specific, sensitive, repeatable and can be applied for vaccines evaluation and detection the SADS-CoV infection in swine industry.

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Hakan Celikhisar

and 2 more

Abstract Objective: To evaluate whether smoking cessation has an effect on female sexual function and quality of life. Methodology: After approval by the local ethics committee, smoking and non-smoking female participants were included in the study and all participants filled the female sexual function index (FSFI) and the short form 36 (SF-36). The same questionnaires were filled again at the 9th month control after smoking cessation. The scores of these questionnaires were compared between the groups. In addition, the FSFI and SF-36 scores of the participants in the smoking group were also compared with the scores at the 9th month after smoking cessation. Results: The rate of FSD was significantly higher in the smoking group when compared with control group (86.0% vs 32.5%; p<0,001). The FSFI total and sub domains score was significantly lower in the smoking group when compared control group [21.5 (min:14.4-max:28.69) and 28.9 (min:17.7-max:32.8); p<0.001 respectively]. The rate of FSD was significantly decreased after nine months smoking cessation (86% to 35.1%; p<0.001). After smoking cessation significant improvements on FSFI total and sub-domain scores and SF-36 sub-domain scores were determined. Conclusion: In this study, it was shown that smoking negatively affected FSD and QOL when compared to healthy non-smoking women, and smoking cessation caused significant improvements in FSFI and SF-36 scores in these women after 9 months. Keywords: female sexual dysfunction, female sexual function index, smoking cessation, the Short Form 36, quality of life.

Igor Vendramin

and 4 more

To the Editor: The interesting and timely paper by Cain et al.1, in press in the Journal of Cardiac Surgery , provides important details concerning the devastating consequences of Mycobacterium chimaera (MC ) infection. In their patient extreme fragility of the mediastinal tissues was observed after repair of an acute aortic dissection; during follow-up multiple reoperations were required to treat recurrent dehiscence of the aortic grafts. Despite repeat explantation of foreign materials infection persisted with mediastinitis and eventual systemic diffusion with fatal outcome.MC infection after open cardiac surgery using cardiopulmonary bypass has been recently reported as a clinical outbreak worldwide and identified as originating by contaminated water in heater-cooler units2. Current experience shows that MC causes a slow-growing and extremely difficult to treat infection with an incubation period which has been recently demonstrated to be as long as >12 years3.We have recently treated a patient, quite similar to that reported by Cain et al.1, who presented with a pseudoaneurysm of the distal suture line twelve years after repair of type A aortic dissection4. At first operation replacement of the ascending aorta and hemiarch using of a Djumbodis®dissection system (Saint Come-Chirurgie, Marseille, France) was performed. At reoperation extremely fragile tissues were noted and, after removing the metallic stent, the aortic arch was replaced with a frozen elephant trunk technique. Cultures of the excised material grewMC . In this case we hypothesized that the stent played an important role in the onset of infection for at least 2 reasons: presence of foreign material in the blood stream and injury to the aortic wall by the edges of the stent. The case described by Cain et al.1 also supports our belief that extreme fragility of the aortic tissues caused by MB was a further important factor in the occurrence of this complication.Interestingly, a delayed diagnosis occurred in both cases; this most likely played a critical role in favouring development of extra‐cardiac manifestations of the disease, in reducing the effectiveness of antibiotic therapy due to immunologic impairment and causing a negative outcome in both patients.MB infection may have different locations ranging from single-organ to systemic manifestations5. When it involves the mediastinum and particularly the major vascular structures often results in life-threatening complications despite proper antimycobacterial treatment. An early diagnosis, even with significantly extended surveillance, appears extremely difficult due to slow-growing and long incubation period of MB .Although no specific guidelines are so far available, intra-operative prevention with improvement of setting and development of heater-cooler units is mandatory and should be based on specific recommendations5.

Timothy Cardozo

and 1 more

Aims of the study Patient comprehension is a critical part of meeting standards of informed consent in study designs. The aim of the study was to determine if extant literature exists to require clinicians to disclose the specific risk that COVID-19 vaccines could worsen disease upon exposure to challenge or circulating virus. Methods used to conduct the study Published literature was reviewed to identify extant preclinical and clinical evidence that COVID-19 vaccines could worsen disease upon exposure to challenge or circulating virus. Results of the study Based on the history of coronavirus vaccine development, COVID-19 vaccines designed to elicit neutralizing antibodies may sensitize vaccine recipients to more severe disease than if they were not vaccinated. Vaccines for SARS, MERS and RSV have never been approved, and the data generated in the development and testing of these vaccines suggest a serious mechanistic concern: that vaccines designed empirically using the traditional approach (consisting of the unmodified or minimally modified coronavirus viral spike to elicit neutralizing antibodies), be they composed of protein, viral vector, DNA or RNA and irrespective of delivery method, may worsen COVID-19 disease via antibody-dependent enhancement (ADE) of either infection or disease. Conclusions drawn from the study and clinical implications The specific and significant COVID-19 risk of ADE should have been and should be clearly and emphatically disclosed to research subjects currently in vaccine trials, as well as those being recruited for the trials and future patients after vaccine approval, in order to meet the medical ethics standard of patient comprehension.

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