Search

Prematurity is the most important prognostic factor for infants born following preterm premature rupture of membranes (PPROM). Therefore, when PPROM occurs between 22 and 33 weeks of gestation, prolonging pregnancy is recommended. Determination of management strategies requires screening for the presence of intra-amniotic infection or inflammation at the time of PPROM diagnosis. If intra-amniotic infection/inflammation is not detected, it is important to monitor the patient to diagnose any new infection/inflammation. We examined the period from PPROM to secondary intra-amniotic infection/inflammation and associated factors.This retrospective study was conducted at a single facility. We examined 26 patients who experienced PPROM between 26 and 33 weeks of gestation and were negative for intra-amniotic infection/inflammation at the time of diagnosis and underwent serial amniocentesis. Antibiotic therapy comprising ampicillin, amoxicillin, and clarithromycin for 7 days was started after the first amniocentesis. The period from PPROM to secondary intra-amniotic infection/inflammation was analyzed using a Kaplan-Meier survival curve. The onset of intra-amniotic infection/inflammation was considered as the time at which amniotic fluid bacterial culture results became positive, the time when amniotic fluid Interleukin (IL)-6 increased beyond 2.6 ng/mL, or the day of delivery if histological chorioamnionitis was observed in the delivered placenta. Patients were treated as censored if no intra-amniotic infection/inflammation could be confirmed in the amniotic fluid and delivered placenta.The median time from PPROM to secondary intra-amniotic infection/inflammation was 18 days. Six patients developed intra-amniotic infection/inflammation, while 13 patients without intra-amniotic infections/inflammation delivered fewer than 7 days after PPROM. No confounding factors at the time of PPROM diagnosis were associated with the time from PPROM until secondary intra-amniotic infection/inflammation.The time between PPROM and onset of secondary intra-amniotic infection/inflammation appears prolonged. Treatments other than antimicrobial agents may need to be added to prolong pregnancy.

Recombinase polymerase amplification (RPA) is a technique that is used to specifically amplify a target nucleic acid sequence. Unlike the polymerase chain reaction (PCR), RPA is performed at a constant temperature between 37 and 42°C. Therefore, it can be potentially used for the onsite detection of various pathogens when combined with DNA extraction and amplicon detection techniques. In this study, we prepared recombinant recombinase and single-stranded DNA-binding protein from T4 phage and used them to examine the effects of reaction conditions and additives on the efficiency of RPA. The results revealed that the optimal pH was 7.5-8.0, optimal potassium acetate concentration was 40-80 mM, and optimal reaction temperature was 37-45°C although dimethyl sulfoxide at 5% v/v and formamide at 5% v/v inhibited the reaction. Our results suggest that RPA could be conducted using a wider range of optimal reaction conditions than those required for PCR and that RPA is highly suitable for point-of-care use.

Objective To examine the effect of Ureaplasma parvum (U. parvum) infection on mouse sperm motility, structure, and fertilizing ability and on embryo development. Design In vitro model of the effects of U. parvum serovar 3 infection on mouse sperm. Setting Basic research laboratory. Intervention(s) None. Animals Mice. Main Outcome Measure(s) Mouse sperm motility was examined using the swim-up method, and their motility parameters were analyzed using the sperm motility analysis system. Localization and invasion of U. parvum were observed with fluorescence, confocal, and scanning electron microscopy. After in vitro fertilization with U. parvum–infected sperm, the quality of the fertilized egg and embryo development were assessed. Result(s) U. parvum was attached and internalized into mouse sperms and localized mainly at the sperm head and midpiece. U. parvum–infected mouse sperms exhibited decreased motility in a dose- and duration-dependent manner. Electron micrographs revealed that U. parvum infection induced the aggregation and morphological destruction of mouse sperm. Infected mouse sperm transported U. parvum into the fertilized egg with reduced fertilization rates, and infected embryo development was impaired. Conclusion(s) U. parvum infection caused deterioration of the mouse sperm quality and its functions, which affected the fertilization rate and embryo development.

The long-term follow-up of lung function (LF) in extremely preterm (EP) infants with bronchopulmonary dysplasia (BPD) has shown a worldwide increase in small airway obstructions (SAO).We investigated the relationships between intrauterine Ureplasma infection in EP infants and bubbly/cystic lung, BPD, and SAO at school age.Placental pathology, placental Ureaplasma DNA (pU-DNA), and cord blood immunoglobulin M (IgM) (C-IgM) were investigated in 360 EP infants born from 1981 to 2004. Maternal amniotic inflammatory response (M-AIR) scores and hemosiderin deposition (HD) were estimated in the chorioamnion. The study subjects were divided into groups based on their M-AIR scores. Their LF at school age was compared with those of 33 healthy siblings.pU-DNA and C-IgM were significantly related to SAO at school age (p 0.012). M-AIR score 3 and pU-DNA1000 units had an odds ratio (OR) of 35 (95% confidence interval: 10-172) and 18 (5.6-67) for bubbly/cystic lung, and 11 (3.1 - 43) and 31 (4.5-349) for severe BPD, and 5.3 (2.1-11) and 12 (2.4-74) for SAO, respectively. The ORs of surfactant treatment, BPD grade III, OOur long-term cohort study of LF in EP infants revealed that intrauterine Ureaplasma was associated with bubbly/cystic lung, severe BPD, and SAO at school age.

Background Recombinase (uvsY and uvsX) from bacteriophage T4 is a key enzyme for recombinase polymerase amplification (RPA) that amplifies a target DNA sequence at a constant temperature with a single-stranded DNA-binding protein and a strand-displacing polymerase. The present study was conducted to examine the effects of the N- and C-terminal tags of uvsY on its function in RPA to detect SARS-CoV-2 DNA. Methods Untagged uvsY (uvsY-Δhis), N-terminal tagged uvsY (uvsY-Nhis), C-terminal tagged uvsY (uvsY-Chis), and N- and C-terminal tagged uvsY (uvsY-NChis) were expressed in Escherichia coli and purified. RPA reaction was carried out with the in vitro synthesized standard DNA at 41ºC. The amplified products were separated on agarose gels. Results The minimal initial copy numbers of standard DNA from which the amplified products were observed were 6 ×105, 60, 600, and 600 copies for the RPA with uvsY-Δhis, uvsY-Nhis, uvsY-Chis, and uvsY-NChis, respectively. The minimal reaction time at which the amplified products were observed were 20, 20, 30, and 20 min for the RPA with uvsY-Δhis, uvsY-Nhis, uvsY-Chis, and uvsY-NChis, respectively. The RPA with uvsY-Nhis exhibited clearer bands than that with either of other three uvsYs. Conclusion The reaction efficiency of RPA with uvsY-Nhis was the highest, suggesting that uvsY-Nhis is suitable for use in RPA.

Background Recombinase (uvsY and uvsX) from bacteriophage T4 is a key enzyme for recombinase polymerase amplification (RPA) that amplifies a target DNA sequence at a constant temperature with a single-stranded DNA-binding protein and a strand-displacing polymerase. The present study was conducted to examine the effects of the N- and C-terminal tags of uvsY on its function in RPA to detect SARS-CoV-2 DNA. Methods Untagged uvsY (uvsY-Δhis), N-terminal tagged uvsY (uvsY-Nhis), C-terminal tagged uvsY (uvsY-Chis), and N- and C-terminal tagged uvsY (uvsY-NChis) were expressed in Escherichia coli and purified. RPA reaction was carried out with the in vitro synthesized standard DNA at 41 °C. The amplified products were separated on agarose gels. Results The minimal initial copy numbers of standard DNA from which the amplified products were observed were 6 × 105, 60, 600, and 600 copies for the RPA with uvsY-Δhis, uvsY-Nhis, uvsY-Chis, and uvsY-NChis, respectively. The minimal reaction time at which the amplified products were observed were 20, 20, 30, and 20 min for the RPA with uvsY-Δhis, uvsY-Nhis, uvsY-Chis, and uvsY-NChis, respectively. The RPA with uvsY-Nhis exhibited clearer bands than that with either of other three uvsYs. Conclusions The reaction efficiency of RPA with uvsY-Nhis was the highest, suggesting that uvsY-Nhis is suitable for use in RPA. Supplementary Information The online version of this article contains supplementary material available 10.1007/s11033-021-07098-y.

Previously, we found that Ureaplasma parvum internalised into HeLa cells and cytosolic accumulation of galectin-3. U. parvum induced the host cellular membrane damage and survived there. Here, we conducted vesicular trafficking inhibitory screening in yeast to identify U. parvum vacuolating factor (UpVF). U. parvum triggered endoplasmic reticulum (ER) stress and upregulated the unfolded protein response-related factors, including BiP, P-eIF2 and IRE1 in the host cells, but it blocked the induction of the downstream apoptotic factors. MicroRNA library screening of U. parvum-infected cells and UpVF-transfected cells identified miR-211 and miR-214 as the negative regulators of the apoptotic cascade under ER stress. Transient expression of UpVF induced HeLa cell death with intracellular vacuolization; however, some stable UpVF transformant survived. U. parvum-infected cervical cell lines showed resistance to actinomycin D, and UpVF stable transformant cell lines exhibited resistance to X-ray irradiation, as well as cisplatin and paclitaxel. UpVF expressing cervical cancer xenografts in nude mice also acquired resistance to cisplatin and paclitaxel. A mycoplasma expression vector based on Mycoplasma mycoides, Syn-MBA (multiple banded antigen)-UpVF, reduced HeLa cell survival compared with that of Syn-MBA after 72 hr of infection. These findings together suggest novel mechanisms for Ureaplasma infection and the possible implications for cervical cancer malignancy. TAKE AWAYS: • Ureaplasmal novel virulence factor, UpVF, was identified. • UpVF triggered ER stress but suppressed apoptotic cascade via miR-211 and -214. • UpVF conferred resistance to anticancer treatments both in vivo and in vitro. • Dual expression of MBA and UpVF in JCVI-syn3B showed host cell damage.

Background: PIK3CA and MDM2 SNP309 have been studied to be associated with cervical cancer. PIK3CA mutation is associated with poor treatment response and low survival rate while MDM2 is associated with tumorigenesis and poor prognosis in cervical cancer. Thus, we determined the prevalence of PIK3CA and MDM2 mutations in Filipino cervical cancer patients. Methods: Twenty-eight formalin-fixed paraffin-embedded cervical squamous cell carcinoma and 16 non-malignant cervix tissue biopsies of Filipino patients were subjected to PIK3CA gene and MDM2 SNP309 (rs2279744) analysis. Results: PIK3CA gene was found mutated in three (10.71 %) out of 28 cervical cancer patients included in this study. Among the HPV-negative cervical cancer patients, two (28.57 %) were positive for PIK3CA mutation and only one (4.76 %) tested positive among the HPV-positive cervical cancer patients. MDM2 SNP309 analysis revealed that T allele (71.43%) was more common in cervical cancer patients compared to the control group. TG genotype (p = 0.03; OR = 0.18, 95% CI 0.04-0.76) was associated with lower rates of cervical cancer when TT genotype was used as a reference point. Conclusion: PIK3CA gene mutation was present among Filipino cervical cancer patients and not in control patients. MDM2 SNP309 analysis revealed that TG genotype has lower association to cervical cancer when compared with the TT and GG genotypes.

Recombinase polymerase amplification (RPA) is an isothermal reaction that amplifies a target DNA sequence with a recombinase, a single-stranded DNA-binding protein (SSB), and a strand-displacing DNA polymerase. In this study, we optimized the reaction conditions of RPA to detect SARS-CoV-2 DNA and RNA using a statistical method to enhance the sensitivity. In vitro synthesized SARS-CoV-2 DNA and RNA were used as targets. After evaluating the concentration of each component, the uvsY, gp32, and ATP concentrations appeared to be rate-determining factors. In particular, the balance between the binding and dissociation of uvsX and DNA primer was precisely adjusted. Under the optimized condition, 60 copies of the target DNA were specifically detected. Detection of 60 copies of RNA was also achieved. Our results prove the fabrication flexibility of RPA reagents, leading to an expansion of the use of RPA in various fields.

Aim The optimal antibiotic regimen for preterm premature rupture of membrane (pPROM) is still unclear. This study aimed to determine the effects of ampicillin-sulbactam (SBT/ABPC) and azithromycin (AZM) on the incidence of bronchopulmonary dysplasia (BPD). Methods This retrospective study included women with singleton gestations and a diagnosis of pPROM between 22 and 27 weeks of gestation. In patients presenting with a high risk of intra-amniotic infection between January 2011 and May 2013, piperacillin or cefmetazole + clindamycin (regimen 1 group; n = 11) was administered, whereas SBT/ABPC and AZM (regimen 2 group; n = 11) were administered in patients presenting a similar risk between June 2013 and May 2016. Results The incidence of moderate or severe infant BPD in the regimen 2 group was significantly lower than that in the regimen 1 group, even when adjusted for gestational age at the time of rupture of membrane, with an odds ratio (95% confidence interval) of 0.02 (1.8 × 10-5 -0.33). The incidence of BPD and total days on mechanical ventilation were significantly lower in the regimen 2 group than in the regimen 1 group. No significant differences were seen in other morbidities. Conclusion In patients with pPROM between 22 and 27 weeks of gestation, the administration of SBT/ABPC and AZM may improve the perinatal outcomes.

AIM The association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and intervillous and decidual pathology in patients with pregnancy loss was investigated. METHODS We performed a cross-sectional study on 243 patients presenting with pregnancy loss for the degree of intervillous fibrin and thrombosis (IT), and decidual fibrin and thrombosis (DT) and determined their MTHFR C677T genotypes. Overall differences in age, body mass index (BMI), gravidity, parity, number of pregnancy losses and gestational period when the pathologic samples were obtained, also were determined. RESULTS There were no significant differences in age, BMI, gravidity, parity, number of pregnancy losses and gestational period, relative to MTHFR C677T genotype (TT vs CT vs CC). There were significantly more T allele carriers and TT genotype patients among patients with severe IT (odds ratio [OR] 1.653, P = 0.033 and OR 2.246, P = 0.032, respectively) and those with severe IT and decidual thrombosis (OR 2.602, P = 0.012 and OR 3.375, P = 0.035, respectively). The CC genotype was protective against the four studied pathologic grades. CONCLUSION To our knowledge, this is the first study showing that the MTHFR C677T TT genotype and T allele are associated with severe intervillous and decidual pathologies in patients with pregnancy loss. Differences in pathologic grades of MTHFR C677T TT genotype could support the hypothesis that further periconceptional treatment for pregnancy loss could be customized depending on single nucleotide polymorphisms.

DNA/RNA helicases, which catalyze the unwinding of duplex nucleic acids using the energy of ATP hydrolysis, contribute to various biological functions involving DNA or RNA. Euryarchaeota-specific helicase Tk-EshA (superfamily 2) from the hyperthermophilic archaeon Thermococcus kodakarensis has been used to decrease generation of mis-amplified products (noise DNAs) during PCR. In this study, we focused on another type (superfamily 1B) of helicase, Tk-Upf1 (TK0178) from T. kodakarensis, and compared its effectiveness in PCR and digital PCR with that of Tk-EshA. For this purpose, we obtained Tk-Upf1 as a recombinant protein and assessed its enzymatic characteristics. Among various double-stranded DNA (dsDNA) substrates (forked, 5' overhung, 3' overhung, and blunt-ended duplex), Tk-Upf1 had the highest unwinding activity toward 5' overhung DNAs. Noise DNAs were also eliminated in the presence of Tk-Upf1 at concentrations 10-fold lower than those required to yield a comparable reduction with Tk-EshA. When a 5' or 3' overhung mis-annealed primer was included as a competitive primer along with specific primers, noise DNAs derived from the mis-annealed primer were eliminated in the presence of Tk-Upf1. In digital PCR, addition of Tk-EshA or Tk-Upf1 increased fluorescent intensities and improved separation between common and risk allele clusters, indicating that both helicases functioned as signal enhancers. In comparison with Tk-EshA, a smaller amount of Tk-Upf1 was required to improve the performance of digital PCR.

The general methods to detect the RNA of severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) in clinical diagnostic testing involve reverse transcriptases and thermostable DNA polymerases. In this study, we compared the detection of SARS-CoV-2 by a one-step real-time RT-PCR method using a heat-resistant reverse transcriptase variant MM4 from Moloney murine leukemia virus, two thermostable DNA polymerase variants with reverse transcriptase activity from Thermotoga petrophila K4 and Thermococcus kodakarensis KOD1, or a wild-type DNA polymerase from Thermus thermophilus M1. The highest performance was achieved by combining MM4 with the thermostable DNA polymerase from T. thermophilus M1. These enzymes efficiently amplified specific RNA using uracil-DNA glycosylase (UNG) to remove contamination and human RNase P RNA amplification as an internal control. The standard curve was obtained from 5 to 10⁵ copies of synthetic RNA. The one-step real-time RT-PCR method’s sensitivity and specificity were 99.44% and 100%, respectively (n = 213), compared to those of a commercially available diagnostic kit. Therefore, our method will be useful for the accurate detection and quantification of SARS-CoV-2., 新型コロナウイルス検出酵素試薬の開発 --独自酵素開発酵素によるOne-Step Real-Time PCR法--. 京都大学プレスリリース. 2021-06-07.

Ureaplasma spp. cause several disorders, such as nongonococcal urethritis, miscarriage, and preterm delivery with lung infections in neonates, characterized by pathological chorioamnionitis in the placenta. Although reports on antibiotic resistance in Ureaplasma are on the rise, reports on quinolone-resistant Ureaplasma infections in Japan are limited. The purpose of this study was to determine susceptibilities to five quinolones of Ureaplasma urealyticum and Ureaplasma parvum isolated from perinatal samples in Japan and to characterize the quinolone resistance-determining regions in the gyrA , gyrB , parC , and parE genes. Out of 28 clinical Ureaplasma strains, we isolated 9 with high MICs of quinolones and found a single parC gene mutation, resulting in the change S83L. Among 158 samples, the ParC S83L mutation was found in 37 samples (23.4%), including 1 sample harboring a ParC S83L–GyrB P462S double mutant. Novel mutations of ureaplasmal ParC (S83W and S84P) were independently found in one of the samples. Homology modeling of the ParC S83W mutant suggested steric hindrance of the quinolone-binding pocket (QBP), and de novo prediction of peptide structures revealed that the ParC S84P may break/kink the formation of the α4 helix in the QBP. Further investigations are required to unravel the extent and mechanism of antibiotic resistance of Ureaplasma spp. in Japan.

Problem Ureaplasma species occasionally cause chorioamnionitis and premature labor. We developed a novel assay employing a loop-mediated isothermal amplification (LAMP) method to detect Ureaplasma parvum and Ureaplasma urealyticum. Method of study Loop-mediated isothermal amplification primers were designed to amplify Ureaplasma-specific ureaseB genes. Four U. parvum strains, 5 U. urealyticum strains and 14 reference bacterial species were evaluated. Forty-six vaginal swab samples were analyzed by LAMP, culture, and PCR. Results Our LAMP primers were specific to each species and had no cross-reaction. Of 46 clinical specimens, the sensitivity, specificity, and positive and negative predictive values of the LAMP method were 100% (12/12), 100% (34/34), 100% (12/12), and 100% (34/34), respectively, whereas those of PCR were 66.7% (8/12), 100% (34/34), 100% (8/8), and 89.5% (34/38), respectively, compared to culture-based detection. Conclusion The LAMP detection method outperformed the culture and PCR methods. Early detection enables appropriate antibiotic selection for improved prenatal outcomes.

Toxoplasma gondii strains have been isolated all over the world and their virulence has been examined mainly using laboratory mice. However, T. gondii differs in virulence depending on the host animal species. Therefore, to evaluate the virulence of each strain in domestic animals, it is necessary to examine using not only mice but also the concerned animals. We have shown that TgCatJpOk4, a T. gondii strain recently isolated in Okinawa, Japan, has a high virulence against laboratory mice, comparable to highest virulent RH strain in mice; however, the virulence to domestic animals remains unknown. In this study, we examined the virulence using the Microminipig. After infection, four out of five infected pigs showed severe clinical symptoms: inappetence, hypoactivity and tachypnea. Eventually, three out of the five infected pigs succumbed before the end of the observation. Among the three dead pigs, histological analysis revealed that interstitial pneumonia and spotty necrosis in the liver indicating that the TgCatJpOk4 strain has a high virulence not only in laboratory mice, but in pigs as well.

Ureaplasma parvum serovar 3 strain, OMC-P162, was isolated from the human placenta of a preterm delivery at 26 weeks’ gestation. In this study, we sequenced the complete genome of OMC-P162 and compared it with other serovar 3 strains isolated from patients with different clinical conditions. Ten unique genes in OMC-P162, five of which encoded for hypothetical proteins, were identified. Of these, genes UPV_229 and UPV_230 formed an operon whose open reading frames were predicted to code for a DNA methyltransferase and a hypothetical protein, respectively. DNA modification analysis of the OMC-P162 genome identified N4-methylcytosine (m4C) and N6-methyladenine (m6A), but not 5-methylocytosine (m5C). UPV230 recombinant protein displayed endonuclease activity and recognized the CATG sequence, resulting in a blunt cut between A and T. This restriction enzyme activity was identical to that of the cultivated OMC-P162 strain, suggesting that this restriction enzyme was naturally expressed in OMC-P162. We designated this enzyme as UpaP162. Treatment of pT7Blue plasmid with recombinant protein UPV229 completely blocked UpaP162 restriction enzyme activity. These results suggest that the UPV_229 and UPV_230 genes act as a type II restriction-modification system in Ureaplasma OMC-P162.

Maternal intrauterine infection/inflammation represents the major etiology of preterm delivery and the leading cause of neonatal mortality and morbidity. The aim of this study was to investigate the anti-inflammatory properties of thioredoxin-1 in vivo and its potential ability to attenuate the rate of inflammation-induced preterm delivery.Two intraperitoneal injections of lipopolysaccharide from Escherichia coli were administered in pregnant mice on gestational day 15, with a 3-h interval between the injections. From either 1 h before or 1 h after the first lipopolysaccharide injection, mice received three intravenous injections of either recombinant human thioredoxin-1, ovalbumin, or vehicle, with a 3-h interval between injections.Intraperitoneal injection of lipopolysaccharide induced a rise of tumor necrosis factor-α, interferon-γ, monocyte chemotactic protein 1, and interleukin-6 in maternal serum levels and provoked preterm delivery. Recombinant human thoredoxin-1 prevented the rise in these proinflammatory cytokine levels. After the inflammatory challenge, placentas exhibited severe maternal vascular dilatation and congestion and a marked decidual neutrophil activation. These placental pathological findings were ameliorated by recombinant human thioredoxin-1, and the rate of inflammation-induced preterm delivery was attenuated.Thioredoxin-1 may thus represent a novel effective treatment to delay inflammation-induced preterm delivery.

Infective endocarditis (IE) of infants is rare, most of which occur associated with congenital heart disease or its cardiac surgery. We experienced a case of sudden death of a four-month-old male infant without congenital heart disease. It was elucidated by postmortem examination that the dead had suffered severe IE, which led him to death. In the microbiological genetic analysis using histological section, the pathogen causing inflammation in the present case was identified as Lactococcus lactis subspecies, although Staphylococci have been reported to be common and important one. Previously reported infectious diseases by Lactococcus lactis subspecies were all adult cases and this is the first report of an infantile death due to Lactococcal IE according to our knowledge. Any fatal disease may be included in sudden death cases targeted for forensic autopsy, even if it is rare. It is expected for forensic pathologists that they note such case and share each experience among themselves and other medical fields to develop a strategy for prevention.

Genital mycoplasmas, including Ureaplasma spp., are among the smallest human pathogenic bacteria and are associated with preterm birth. Electron microscopic observation of U. parvum showed that these prokaryotes have a regular, spherical shape with a mean diameter of 146 nm. U. parvum was internalized into HeLa cells by clathrin‐mediated endocytosis and survived for at least 14 days around the perinuclear region. Intracellular U. parvum reached endosomes in HeLa cells labeled with EEA1, Rab7, and LAMP‐1 within 1 to 3 hr. After 3 hr of infection, U. parvum induced the cytosolic accumulation of galectin‐3 and was subsequently entrapped by the autophagy marker LC3. However, when using atg7 −/− MEF cells, autophagy was inadequate for the complete elimination of U. parvum in HeLa cells. U. parvum also colocalized with the recycling endosome marker Rab11. Furthermore, the exosomes purified from infected HeLa cell culture medium included U. parvum. In these purified exosomes ureaplasma lipoprotein multiple banded antigen, host cellular annexin A2, CD9, and CD63 were detected. This research has successfully shown that Ureaplasma spp. utilize the host cellular membrane compartments possibly to evade the host immune system.