Polymerase Chain Reaction Technology Research Articles

Different Laboratory Diagnostic Procedures Including PCR Directly from Urine Specimens from Suspected Patients of UTI

Background: Urinary tract infection (UTI) is among the most common bacterial infections and possess significant healthcare burden. Hence a study was necessary to apply PCR technology directly to clinical specimens to allow early and accurate identification of pathogens of UTI. Objective: Diagnosis of major uropathogens by different laboratory diagnostic procedures including polymerase chain reaction (PCR) directly from urine specimens from suspected patients of urinary tract infection. Methods: This study was carried out in the department of Microbiology, Mymensingh Medical College during the period from July 2016 to June 2017. Urine specimens were collected and isolation and identification of major uropathogens (Escherichiacoli Klehsiella pneumonias, Proteusmirabilis, and Pseudomonas aeruginosa) were done by standard microbiological procedure anbiochemical tests. PCR was performed by using standard protocol with species specific primer for detection offim H gene for Escherichia coli, fimK gene for Klehsiella paeunomiae, UreC for Proteus mirabilis and ETA for Pseudomonas aeruginasa. Results: Out of 250 urine specimens, 200 specimens were isolated and identified by culture and different biochemical methods which were supported by microscopical examination and at the same time PCR could detect species specific genes in 201 specimens directly from urine of suspected UTI patient Escherichia coli was responsible as a leading causative pathogen in both outpatient department and in patient department. Urine specimens was higher in female in both out patient population and inpatient population. Culture positivity of in patient population among the male (45.5%) was slighty higher than that of outpatient population (34.5%). The predominant age group suffered from UTI in case of outpatient population was >15-30 but for the in patient population, the age group was 60 years and above. 90 culture positive in patient population, 43 (95.5%) were from the gynae unit, 23 (92%) were from surgery unit, 8 (72.7%) were from the medicine unit, 12 (85.7%) were from orthopaedic unit and 4 (80%) were from paediatric unit. On the other hand Pseudomonas aeruginosa Profeus mirabilis and Klebsiella pneumonia were more prevalent in in-patient department and it was 21.1%, 5.6% and 5.5% respectively, Among the 50 culture negative urine specimens, 14 (28%) showed PCR positive for Escherichia coli, Klehsiella pneumonia and Pseudomonas aeruginosa. Conclusion: This study revealed that, the prevalence of UTI is high n MMCH Single pathogen base uniplex PCR was found superior than standard culture and less time consuming. Because uniplex PCR could detect many (28%) culture negative cases.

Advances in Diagnosis and Treatment of Cytomegalovirus Gastrointestinal Infection in Immunocompetent Adults

Cytomegalovirus (CMV), a kind of human herpes virus, is highly prevalent globally. It was believed that CMV posed a considerable risk only in newborns and immunocompromised individuals in the past, but there are increasing reports that CMV caused adverse outcomes in immunocompetent adults. The gastrointestinal canal (especially colon) is one of the usual sites of cytomegalovirus infection. Moreover, severe CMV gastrointestinal disease can lead to considerable mortality. Male, age ≥55 years, immunomodulatory comorbidities (such as kidney failure, pregnancy, diabetes mellitus, or non-hematological malignancies without treatment) and the need for surgical intervention are factors that are not favorable to survival. When patients have unfavorable risk factors for survival or serious complications, antiviral treatment should be administered. Targeted antiviral therapy with intravenous ganciclovir or valganciclovir was suitable for severe CMV disease in immunocompetent adults before the advent of new and safer anti-herpesvirus drugs. Although there are many simple ways to detect the presence of CMV, most of them cannot distinguish between latent infection and active disease, which makes clinical decision-making difficult. CMV gastrointestinal disease has no specific clinical and endoscopic manifestations, and the diagnosis is to a large extent dependent on histopathology and tissue CMV polymerase chain reaction technology. Quantitative testing of tissue CMV DNA is a useful diagnostic tool, but further research is needed to explain the quantitative value, such as obtaining a viral load cutoff to decide whether to apply antiviral therapy.

MiR-34c regulates the proliferation and apoptosis of lung cancer cells

Purpose: As miR-34c acts as a tumor suppressant for multiple cancers, the purpose of this study was to investigate that role that miR-34c plays in the proliferation and apoptosis of lung cancer.
 
 Methods: The expression of miR-34c in 600 patients with lung cancer was quantitatively analyzed with real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR) technology and correlated to
 clinical pathological parameters. The CCK-8 analysis and flow cytometry were carried out to detect cell proliferation and apoptosis in miR-34c-mimic transfected cell lines. Moreover, the regulation of miR-34c to interleukin-6 (IL-6) in cell lines was detected by western blot, qRT-PCR and dual-luciferase reporter assay.
 
 Results: The expression of miR-34c was downregulated in lung cancer compared with adjacent normal tissues. The expression level of miR-34c was linked to stromal invasion. Furthermore, overexpressing miR-34c played an active role in effectively inhibiting cell proliferation and inducing apoptosis. In addition, a significant inverse relationship was exhibited between the expression of miR-34c and IL-6 in tumor tissues.
 
 Conclusion: At the molecular level, IL-6 can be used as a direct target of miR-34c in the treatment of lung cancer cells and miR-34c can be used as an effective biomarker and therapeutic target for lung cancer.

Using the rDNA Internal Transcribed Spacer 1 to Identify the Invasive Pest Rhagoletis cerasi (Diptera: Tephritidae) in North America.

The cherry-infesting fruit fly Rhagoletis cerasi Loew is a significant commercial pest in Europe that has recently invaded North America. To date, it has been trapped only in Canada and northwestern counties of New York. It has the potential to spread further and threaten production and movement of cherry commodities. Timely diagnosis of the pest will facilitate surveys and quick response to new detections. Adult morphology of the pest is distinct from other flies in North America. However, when flies are significantly damaged on traps or the immature life stages are found in fruits, molecular methods of identification are important to confirm presence and host-use records. Other than DNA sequencing of genes from flies which takes over a day to complete, there are no timely methods of molecular identification for this pest. In this study, we report the first sequence record of the internal transcribed spacer 1 (ITS1) from R. cerasi and develop two diagnostic tests for the pest based on ITS1 differences among species in North America. The tests use loop-mediated isothermal amplification (LAMP) and multiplex, conventional polymerase chain reaction (mcPCR) technologies that target the same region of the R. cerasi ITS1 sequence. Both tests performed well when tested against collections of R. cerasi from North America and Europe, generating Diagnostic Sensitivity estimates of 98.4-99.5%. Likewise, the tests had relatively high estimates of Diagnostic Specificity (97.8-100%) when tested against Rhagoletis Loew species present in North America that also use cherry as a developmental host.

Expression of MiR-608 in Nonsmall Cell Lung Cancer and Molecular Mechanism of Apoptosis and Migration of A549 Cells.

Objective This Work is aimed at exploring the effect of microRNA (MiR)-608 on the function of nonsmall cell lung cancer (NSCLC) A549 cells and related mechanisms. Methods Blood samples of 106 NSCLC patients (experimental group) as well as 124 normal people (control group) were selected for relevant investigation. Polymerase chain reaction (PCR) as well as DNA sequencing was used to determine the genotyping of the MiR-608 rs4919510 polymorphism. MiR-608 expression in cells was detected by real-time PCR technology. Western blotting was used to detect changes in protein levels. NSCLC tissues as well as adjacent tissues were explored in 33 patients undergoing surgery. Results MiR-608 rs4919510 does not influence the incidence of NSCLC patients. In addition, MiR-608 expression was downregulated in the tumor tissue of NSCLC patients, while the transcription factor activating enhancer-binding protein 4 (TFAP4) expression was upregulated. MiR-608 promotes DOX- (Doxorubicin-) induced apoptosis by negatively regulating TFAP4 expression in NSCLC tissue. TFAP4 can significantly inhibit the migration of A549 cells. Conclusion The findings in this investigation can contribute to the effective treatment of NSCLC patients. Also, the investigation can provide some theoretical support for the application of new targets for NSCLC treatment.

Utility of the respiratory viral panel as an antimicrobial stewardship tool.

The development of rapid diagnostics has revolutionized antimicrobial stewardship with efforts targeting earlier de-escalation or discontinuation of antibiotics. The respiratory viral panel (RVP) is one tool quickly able to detect common viral and bacterial pathogens using polymerase chain reaction technology. Utility may be further enhanced in conjunction with procalcitonin (PCT). However, the optimal use of the RVP to the clinical pharmacist in the treatment of community-acquired respiratory infections remains unclear. The purpose of this guide is to review the available literature regarding the impact of the RVP with and without procalcitonin on antimicrobial stewardship efforts and to provide guidance on how to use each of these tools. In total, 13 studies were included, 5 of which utilized PCT in conjunction with RVP and 8 of which did not use PCT. The majority of studies were retrospective in nature, and the most common outcomes evaluated were antibiotic days of therapy (DOT) and time to antibiotic discontinuation. After review, RVP alone has limited value to antimicrobial stewardship; however, when used in conjunction with procalcitonin, RVP has the potential to reduce antibiotic use and duration.

Development of a sensitive molecular diagnostic assay for detecting Borrelia burgdorferi DNA from the blood of Lyme disease patients by digital PCR.

Lyme disease patients would greatly benefit from a timely, sensitive, and specific molecular diagnostic test that can detect the causal agent Borrelia burgdorferi at the onset of symptoms. Currently available diagnostic methods recommended by the Centers for Disease Control and Prevention for Lyme disease involve indirect serological tests that rely on the detection of a host-antibody response, which often takes more than three weeks to develop. With this process, many positive cases are not detected within a timely manner, preventing a complete cure. In this study, we have developed a digital polymerase chain reaction (PCR) assay that detects Lyme disease on clinical presentation with a sensitivity two-fold higher than that of the currently available diagnostic methods, using a cohort of patient samples collected from the Lyme disease endemic state of Connecticut, USA, in 2016–2018. Digital PCR technology was chosen as it is more advanced and sensitive than other PCR techniques in detecting rare targets. The analytical detection sensitivity of this diagnostic assay is approximately three genome copies of B. burgdorferi. The paucity of spirochetes in the bloodstream of Lyme disease patients has hindered the clinical adoption of PCR-based diagnostic tests. However, this drawback was overcome by using a comparatively larger sample volume, applying pre-analytical processing to the blood samples, and implementing a pre-amplification step to enrich for B. burgdorferi-specific gene targets before the patient samples are analyzed via digital PCR technology. Pre-analytical processing of blood samples from acute patients revealed that the best sample type for Lyme disease detection is platelet-rich plasma rather than whole blood. If detected in a timely manner, Lyme disease can be completely cured, thus limiting antibiotic overuse and associated morbidities.

Response of soil fungal communities to continuous cropping of flue-cured tobacco

Fungal communities are considered to be critically important for crop health and soil fertility. However, our knowledge of the response of fungal community structure to the continuous cropping of flue-cured tobacco is limited, and the interaction of soil fungal communities under different cropping systems remains unclear. In this study, we comparatively investigated the fungal abundance, diversity, and community composition in the soils in which continuous cropping of flue-cured tobacco for 3 years (3ys), 5 years (5ys), and cropping for 1 year (CK) using quantitative polymerase chain reaction and high-throughput sequencing technology. The results revealed that continuous cropping of flue-cured tobacco changed the abundance of soil fungi, and caused a significant variation in fungal diversity. In particular, continuous cropping increased the relative abundance of Mortierellales, which can dissolve mineral phosphorus in soil. Unfortunately, continuous cropping also increased the risk of potential pathogens. Moreover, long-term continuous cropping had more complex and stabilize network. This study also indicated that available potassium and available phosphorous were the primary soil factors shifting the fungal community structure. These results suggested that several soil variables may affect fungal community structure. The continuous cropping of flue-cured tobacco significantly increased the abundance and diversity of soil fungal communities.

Colonisation with extended spectrum beta-lactamase-producing and carbapenem-resistant Enterobacterales in children admitted to a paediatric referral hospital in South Africa.

There are few studies describing colonisation with extended spectrum beta-lactamase-producing Enterobacterales (ESBL-PE) and carbapenem-resistant Enterobacterales (CRE) among children in sub-Saharan Africa. Colonisation often precedes infection and multi-drug-resistant Enterobacterales are important causes of invasive infection. In this prospective cross-sectional study, conducted between April and June 2017, 200 children in a tertiary academic hospital were screened by rectal swab for EBSL-PE and CRE. The resistance-conferring genes were identified using polymerase chain reaction technology. Risk factors for colonisation were also evaluated. Overall, 48% (96/200) of the children were colonised with at least one ESBL-PE, 8.3% (8/96) of these with 2 ESBL-PE, and one other child was colonised with a CRE (0.5% (1/200)). Common colonising ESBL-PE were Klebsiella pneumoniae (62.5%, 65/104) and Escherichia coli (34.6%, 36/104). The most frequent ESBL-conferring gene was blaCTX-M in 95% (76/80) of the isolates. No resistance- conferring gene was identified in the CRE isolate (Enterobacter cloacae). Most of the Klebsiella pneumoniae isolates were susceptible to piperacillin/tazobactam (86.2%) and amikacin (63.9%). Similarly, 94.4% and 97.2% of the Escherichia coli isolates were susceptible to piperacillin/tazobactam and amikacin, respectively. Hospitalisation for more than 7 days before study enrolment was associated with ESBL-PE colonisation. Approximately half of the hospitalised children in this study were colonised with ESBL-PE. This highlights the need for improved infection prevention and control practices to limit the dissemination of these microorganisms.

Longitudinal Molecular Profiling in Patients with IDH1-Mutant Newly Diagnosed Acute Myeloid Leukemia Treated with Ivosidenib

Longitudinal Molecular Profiling in Patients with IDH1-Mutant Newly Diagnosed Acute Myeloid Leukemia Treated with Ivosidenib

Determination some virulence genes (avrxacE2, avrxacEl, hrpG, acrAB) in Pantoea spp. isolated from hospitals of Al-Diwaniyah city, Iraq

Pantoea spp. is one of the opportunistic pathogens, which causes the spread of hospital infection due to its transformation from bacteria to plant organisms to human pathogenic bacteria. A total of 623 samples were collected and distributed as 483 samples of different clinical cases (77.52%) and 140 environmental samples (22.47%) from Diwaniyah city hospitals. The results showed that 24 isolates of pantoea spp.s had been confirmed using API-20E Polymerase chain reaction technology. The current study reported the presence of two types of pathogens for the Pantoea spp.: the first is Pantoea agglomerans and Pantoea calida in hospitals in the city of Diwaniyah. Pantoea agglomerans was occurring in the studied isolates at a higher rate (2.27%) than Pantoea calida. All isolates of Pantoea spp were tested for the prevalence of virulence genes (avrxacE2, avrxacEl, hrpG, acrAB) using the polymerase chain reaction (PCR) technique. The highest incidence of hrpG was recorded as 79.16%, followed by avraxacE2 gene were 13 (54.16%). The current study did not record any presence of the virulence genes (avrxacE1 acrAB) among the isolates of Pantoea spp.

SERS Platform Based on Bimetallic Au-Ag Nanowires-Decorated Filter Paper for Rapid Detection of miR-196ain Lung Cancer Patients Serum

Detecting microRNA (miRNA) biomarkers expression is of great significance for the diagnosis and treatment of lung cancer. Surface-enhanced Raman scattering (SERS) has achieved microRNA sensing for the diagnosis of primary liver cancers. In this work, we developed a SERS technology for the rapid detection of lung cancers-related miRNA (miR-196a) using bimetallic Au-Ag nanowire (AgNW@AuNPs) substrates coupled with the target hairpin DNA. The finite-difference time-domain simulation proved that a large number of “hot spots” were generated between the AgNW and AuNPs, which resulted in a huge enhancement of the signal of Raman reporters. Filter paper treated by hexadecenyl succinic anhydride hydrophobic and modified with AgNWs@AuNPs was used as capturing substrate. The detection limits of miR-196a in PBS and serum were as low as 96.58 aM and 130 aM, respectively. Studies on nonspecific sequence and single-base mismatch of miRNA demonstrated that SERS-based platform was highly selective, excellent uniform, and reproducible. Finally, the platform was used to show that the miR-196a expression in the serum of lung cancer patients was much higher than that in healthy people. The detection results indicated that the SERS platform had potential applications in cancer diagnosis and might be a viable alternative to the conventional miRNA detection method, the real-time polymerase chain reaction (RT-PCR) technology.

Establishment of polymerase chain reaction method in Chinese Pharmacopoeia (2020 edition)

With the application and popularization of PCR(polymerase chain reaction) technology in drug quality control, the ge-neral rule of PCR has been approved to be listed in the Chinese Pharmacopoeia(2020 edition). This rule has set general quality stan-dards for species identification in Chinese herbal medicine and biochemical medicine, as well as quality control of other medicines. The general rule is composed of general requirements for instruments, general requirements for PCR system, operational suitability test, measurement procedure(sample pretreatment, templates preparation, primers, nucleic acid amplification, reaction products detection, result judgment) and notes, etc. In this article, we introduced the general rule of PCR and its drafting instructions. Furthermore, its application perspective in Chinese herbal medicine and biochemical medicine was discussed.

Conventional PCR assisted single-component assembly of spherical nucleic acids for simple colorimetric detection of SARS-CoV-2

Continuous identification of suspected infectious cases is crucial to control the recent pandemic caused by the novel human coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2). Real-time polymerase chain reaction (real-time PCR) technology cannot be implemented easily and in large scale in some communities due to lack of resources and infrastructures. Here, we report a simple colorimetric strategy derived from linker-based single-component assembly of gold nanoparticle-core spherical nucleic acids (AuNP-core SNAs) for visual detection of PCR products of SARS-CoV-2 ribonucleic acid (RNA) template. A palindromic linker is designed based on SARS-CoV-2 specific E gene to program the identical colloidal SNAs into large assemblies along with a distinct red-to-purple color change. The linker acts as a probe of SARS-CoV-2 RNA in conventional PCR reaction. In the presence of the correct template the palindromic linker, which is complementary to a short region within the target amplicon, is cleaved by 5′-exonuclease activity of deoxyribonucleic acid (DNA) polymerase. Cleavage of the palindromic linker during the amplification process inhibits the single-component assembly formation of SNAs. So, positive and negative viral samples produce simply red and purple colors in the post PCR colorimetric test, respectively. Evaluation of the samples obtained from cases with laboratory-confirmed SARS-CoV-2 infection revealed that our assay can rival with real-time PCR method in sensitivity.

Detection and Characterization of Salmonella enterica Serotypes by Simple PCR Technologies.

Polymerase chain reaction (PCR) is a molecular-based technology that has revolutionized diagnostics and characterization of pathogens, and thus affecting how we understand disease landscape. This technology has been found amenable to application on various strategies for management and control of infectious diseases. The main advantage with PCR technologies, when applied optimally, is the high sensitivity and short-turn-around time for results, thus rendering the strategy attractive to researchers in infectious diseases and public health. In this chapter, we describe PCR approaches that are innovative and easy to deploy in a laboratory with medium range infrastructure investment.

Building Customizable Multisite‐Targeting c‐Myc shRNA Array into Branch‐PCR‐Constructed DNA Nanovectors for Enhanced Tumor Cell Suppression

AbstractRNA interference (RNAi) has been extensively used to downregulate abnormal excessive mRNA in treating intractable diseases like cancers. Albeit with the success of siRNA drugs, the development of shRNA (small hairpin RNA) as RNAi drugs still meets the great challenge in clinical treatments for lacking the suitable delivery vector to express numerous shRNAs in cells. Considering our previously established branch‐PCR (branched polymerase chain reaction) technology, we herein introduced a multisite‐targeting c‐Myc shRNA array into DNA nanovectors via branch‐PCR. The results indicated that this kind of DNA nanovector retained better serum stability than plasmids and linear DNA. The cell viability test further showed that the transcription of c‐Myc shRNA arrays greatly enhanced the anti‐cancer activity by eliminating approximately 98.2 % c‐Myc mRNA, which posed a technical advance in augmenting the gene silencing efficiency of vector‐expressed shRNAs in cells. Hence, it would be promising to use this customizable and stable shRNA array‐based DNA nanovectors to enhance the curable efficacy of shRNAs in cancer treatment.

Long-Term No-Tillage and Straw Retention Management Enhances Soil Bacterial Community Diversity and Soil Properties in Southern China

Conservation farming practices, such as no-tillage and crop residue retention, have been proposed as sustainable management practices. However, it remains unclear how different tillage practices and rice straw retention affect the soil bacterial community (SBC) and the soil C/N ratio in the long term. The objective of this study was to evaluate changes in SBC composition and abundance and soil properties (e.g., carbon (C), nitrogen (N)) and determine their relationship to the soil C/N ratio under long-term no-tillage and straw retention techniques. This study investigates the effect of a long-term field experiment begun in 2008 and continued until 2019 to measure the response of the SBC and soil properties and their relation to different tillage practices, including no-tillage (NT), no-tillage and straw mulching (NT-SM), conventional tillage (CT), conventional tillage and straw mulching (CT-SM), and conventional tillage and straw retention (CT-SR). Soil samples were collected at depths of 0–5 cm (A), 5–10 cm (B), and 10–20 cm (C) after rice harvesting in the early and late growing seasons in 2018–2019. The Illumina MiSeq sequencing and quantitative polymerase chain reaction (PCR) technology was used to analyze changes in SBC diversity in soil and determined the changes in the soil C/N ratio and their relationship with the SBC diversity. The results showed that the Proteobacteria, Acidobacteria, and Chloroflexi were the dominant phyla in the soil and accounted for 61.26%, 59.39%, and 55.62% of the total bacteria in the A, B, and C soil layers, respectively. The NT treatment increased SBC diversity, the number of operational taxonomic units (OTUs), and the proportion of Proteobacteria across the soil depths. Similarly, straw retention also significantly improved SBC diversity, soil organic C (SOC), total N (TN), soil C/N ratio, and the abundance of Proteobacteria and Acidobacteria in the soil layers A and B. The NT-SM treatment increased the SOC, TN, and soil C/N ratio by 30%, 21%, and 6% in 2018 and by 33, 25% and 7% in 2019, respectively, across the seasons and layers compared to the CT treatment. The NT-SM treatment had the highest soil bacterial diversity index, and the CT-SR treatment had the highest soil bacterial abundance and number of OTUs. The redundancy analysis showed that Acidobacteria were highly positively correlated with the soil C/N ratio. The results demonstrate that conservation tillage practices, i.e., no-tillage and straw retention, increase the SBC diversity and soil C/N ratio, thereby enhancing soil organic C and total N and changing soil microbial ecology. As a result, sustainable crop production and profitable agro-ecosystems are ensured.

Highly Sensitive Quantification of Plasma Severe Acute Respiratory Syndrome Coronavirus 2 RNA Sheds Light on its Potential Clinical Value

BackgroundCoronavirus disease 2019 (COVID-19) is a global public health problem that has already caused more than 662,000 deaths worldwide. Although the clinical manifestations of COVID-19 are dominated by respiratory symptoms, some patients present other severe damage such as cardiovascular, renal and liver injury or/and multiple organ failure, suggesting a spread of the SARS-CoV-2 in blood. Recent ultrasensitive polymerase chain reaction (PCR) technology now allows absolute quantification of nucleic acids in plasma. We herein intended to use the droplet-based digital PCR technology to obtain sensitive detection and precise quantification of plasma SARS-CoV-2 viral load (SARS-CoV-2 RNAaemia) in hospitalized COVID-19 patients.MethodsFifty-eight consecutive COVID-19 patients with pneumonia 8 to 12 days after onset of symptoms and 12 healthy controls were analyzed. Disease severity was categorized as mild-to-moderate in 17 patients, severe in 16 patients and critical in 26 patients. Plasma SARS-CoV-2 RNAaemia was quantified by droplet digital Crystal Digital PCR™ next-generation technology (Stilla Technologies, Villejuif, France).ResultsOverall, SARS-CoV-2 RNAaemia was detected in 43 (74.1%) patients. Prevalence of positive SARS-CoV-2 RNAaemia correlated with disease severity, ranging from 53% in mild-to-moderate patients to 88% in critically ill patients (p=0.036). Levels of SARS-CoV-2 RNAaemia were associated with severity (p=0.035). Among nine patients who experienced clinical deterioration during follow-up, eight had positive SARS-CoV-2 RNAaemia at baseline while only one critical patient with undetectable SARS-CoV-2 RNAaemia at the time of analysis died at day 27.ConclusionSARS-CoV-2 RNAaemia measured by droplet-based digital PCR constitutes a promising prognosis biomarker in COVID-19 patients

Effects of short-term manure nitrogen input on soil microbial community structure and diversity in a double-cropping paddy field of southern China

The soil physicochemical properties and soil microbial communities were affected by different fertilizer management. Fertilizer regime were closely relative to the soil texture and nutrient status in a double-cropping paddy field of southern China. However, there was limited information about the influence of different manure nitrogen (N) input on soil microbial communities in a double-cropping rice (Oryza sativa L.) field. Therefore, the short-term different manure N input rate management on soil bacterial and fungal diversity in a double-cropping paddy field of southern China were studied by using Illumina sequencing and quantitative real-time polymerase chain reaction technology in the present paper. The filed experiment were including 100% N of chemical fertilizer (M0), 30% N of organic manure and 70% N of chemical fertilizer (M30), 50% N of organic manure and 50% N of chemical fertilizer (M50), 100% N of organic manure (M100), and without N fertilizer input as control (CK). The results showed that diversity indices of soil microbial communities with application of organic manure and chemical N fertilizer treatments were higher than that of CK treatment. Application of organic manure and chemical N fertilizer management increase soil bacterial abundance of the phylum Actinobacteria, Proteobacteria and Gammaproteobacteria, and soil fungi abundance of the phylum Basidiomycota and Zygomycota were also increased. Compared with CK treatment, the value of Richness, Shannon and McIntosh indices, and taxonomic diversity were increased with M30, M50 and M100 treatments. This finding demonstrated that M30, M50 and M100 treatments modify soil bacterial and fungal diversity. Therefore, the combined application of organic manure and chemical fertilizer N management could significantly increase the abundance of profitable functional bacteria and fungi species in a double-cropping rice field of southern China.

Clinical and Microbiological Effects of Weekly Supragingival Irrigation with Aerosolized 0.5% Hydrogen Peroxide and Formation of Cavitation Bubbles in Gingival Tissues after This Irrigation: A Six-Month Randomized Clinical Trial.

Introduction The study investigated the effect of weekly supragingival irrigation with aerosolized 0.5% hydrogen peroxide (H2O2) solution as a maintenance periodontal therapy on clinical and microbiological parameters in patients with chronic periodontitis. The other purpose was to investigate whether cavitation bubbles can penetrate not only into periodontitis-damaged tissues but also into ex vivo porcine healthy periodontal tissues. Materials and Methods The study included 35 systemically healthy patients with chronic periodontitis (CP). After nonsurgical periodontal debridement (NSPD), all patients were randomized into two groups: the Control group (NSDP alone, n = 18) and the Test group (NSDP plus supragingival irrigation, n = 17). Clinical (Approximal Plaque Index (API), Bleeding Index (BI), and Modified Gingival Index (MGI)) and microbiological (Polymerase Chain Reaction technology (using a micro-IDent® kit)) measurements were performed at the initial time point, 3 months, and 6 months after NSPD. The impact of supragingival irrigation on diseased gingival tissues of CP patients (n = 5) and on ex vivo porcine healthy gingival tissue samples (n = 3) was evaluated to estimate morphological changes in healthy and diseased gingival tissues. Results Morphological data revealed that supragingival irrigation caused the formation of cavitation bubbles in diseased gingival tissue of CP patients and in healthy porcine gingival tissues. The decrease in API, BI, and MGI scores after 6 months in the Test group significantly (p ≤ 0.01, p ≤ 0.05, and p ≤ 0.01, respectively) exceeded that in the Control group. Test group patients demonstrated a decrease in periodontal sites showing Pocket Probing Depth > 4 mm and, after 6 months, a statistically significant decrease in the proportion of periopathogenic bacteria. Conclusion The effectiveness of mechanical periodontal treatment combined with weekly supragingival irrigation with aerosolized 0.5% H2O2 solution on clinical and microbiological parameters of periodontal tissues of periodontitis patients is reliably higher than that of mechanical periodontal debridement alone. It has been found that cavitation bubbles as a result of irrigation with the aerosolized 0.5% hydrogen peroxide solution can form not only in periodontal tissues of periodontitis patients but also in ex vivo porcine healthy gingival tissues.