Lower Induction Rate Research Articles

Design, Synthesis, and Activity Evaluation of C-23-Modified 5-O-Mycaminosyltylonolide Derivatives.

The widespread use of tylosin family drugs in clinical practice has led to bacterial resistance and reduced therapeutic efficacy. We designed and synthesized a series of new semisynthetic derivatives of tylosin with 5-O-mycaminosyltylonolide as the mother nucleus, mainly by introducing a variety of amino groups at its C-23 position. Some of the compounds showed high antibacterial activity against Gram-negative and Gram-positive bacteria. These findings indicate that the best compound, c9, possessed significant antibacterial activity (MIC = 0.5 ug/mL), excellent bactericidal efficacy, and a low induction rate of drug resistance against Staphylococcus aureus and Escherichia coli; it also showed good antibacterial activity against drug-resistant bacteria. In addition, compound c9 has a low toxicity in vitro and in vivo. In conclusion, compound c9 could be a potential antimicrobial lead compound that could also contribute to the development of macrolide antibiotics.

Visual and patient reported outcomes provided by a refractive multifocal intraocular lens based on continuous transitional focus

PurposeTo analyze the quality of vision of patients implanted bilaterally with the multifocal Precizon Presbyopic intraocular lens (IOL), as well as to evaluate the visual performance provided by the lens.SettingVissum Miranza Alicante.DesignProspective multicenter study.Methods56 patients (mean age 65.0 ± 8.7 years old) underwent bilateral implantation with multifocal Precizon Presbyopic IOL. The quality of vision was assessed by a quality of vision questionnaire at 6 months after the implantation procedure, a complete eye examination was also performed including visual and refractive measurements, defocus curve and contrast sensitivity assessment. Visual and refractive variables were compared in preoperative, 3-month postoperative and 6-month postoperative visits by Wilcoxon test.ResultsThe quality of vision analysis showed the absence of severe glare and severe haloes in all evaluated patients. Likewise, non-symptoms of glare, haloes and starbursts were seen in 75%, 68%, and 55% of subjects, respectively. Efficacy and safety index was 1.26 and 1.42, respectively. The 6-month postoperative binocular uncorrected distance visual acuity and near uncorrected visual acuity were 0.00 ± 0.09 and 0.20 ± 0.13 logMAR, respectively. Mean spherical equivalent was 0.29 ± 0.45 D.ConclusionsThe Precizon Presbyopic NVA IOL (OPHTEC BV) provides a suitable quality of vision with a low rate of disturbance photic phenomena induction, as well as an excellent visual performance at main distances of sight accomplishing the visual demands of the majority of patients.

In vivo tetraploid induction of mono-embryonic citrus genotypes by colchicine treatment

Polyploid holds great significance in citrus breeding, to produce dwarf tetraploid rootstocks with wide adaptability and triploid scion varieties bearing seedless fruits. In citrus, tetraploids have been generated through somatic hybridization and autonomous chromosome doubling of nucellar embryos. However, most tetraploids were recovered from poly-embryonic (apomictic) citrus, while tetraploids of mono-embryonic (non-apomictic) citrus were seldomly reported. Herein, we developed an in vivo tetraploid induction method by colchicine treatment, which is especially high-efficient in mono-embryonic citrus. The epicotyl of citrus seedling was decapitated and incubated in dark for different time durations (0–15 d) to induce callus formation on the epicotyl wound. The callus on wound was then immersed in different concentrations (0.0125 %-0.100 %) of colchicine for 2 h, enabling regeneration of tetraploid shoots. We achieved high tetraploid induction rate (20.69 %) but low mixoploid induction rate (1.72 %), when 0.025 % colchicine was applied on wound cultured in dark for 9 d By using this method, 147 tetraploids were recovered from mono-embryonic mandarin, tangerine, sweet orange, pummelo and citron. Our method exhibited high tetraploid induction efficiency (14.28 %-20.69 %), low rate of mixoploid (1.72 %-5.30 %), short recovery period (45 d), and no need of tissue culture. The majority (75 %-100 %) of the recovered tetraploids maintained stable ploidy during subsequent growth, and the mono-embryonic nature of the tetraploids was identified by InDel marker analysis. The mono-embryonic tetraploids obtained herein enriched polyploid germplasm pool for citrus breeding.

Comparative Analysis of the Biochemical Composition, Amino Acid, and Fatty Acid Contents of Diploid, Triploid, and Tetraploid Crassostrea gigas.

Tetraploid oysters are artificially produced oysters that do not exist in nature. The successful breeding of 100% triploid oysters resolved the difficulties of traditional drug-induced triploids, such as the presence of drug residues and a low triploid induction rate. However, little is known concerning the biochemical composition and nutrient contents of such tetraploids. Therefore, we investigated compositional differences among diploid, triploid, and tetraploid Crassostrea gigas as well as between males and females of diploids and tetraploids. The findings indicated that glycogen, EPA, ∑PUFA, and omega-3 contents were significantly higher in triploid oysters than in diploids or tetraploids; tetraploid oysters had a significantly higher protein content, C14:0, essential amino acid, and flavor-presenting amino acid contents than diploids or triploids. For both diploid and tetraploids, females had significantly higher levels of glutamate, methionine, and phenylalanine than males but lower levels of glycine and alanine. In addition, female oysters had significantly more EPA, DHA, omega-3, and total fatty acids, a result that may be due to the fact that gonadal development in male oysters requires more energy to sustain growth, consumes greater amounts of nutrients, and accumulates more proteins. With these results, important information is provided on the production of C. gigas, as well as on the basis and backing for the genetic breeding of oysters.

Efficient isolated microspore culture protocol for callus induction and plantlet regeneration in japonica rice (Oryza sativa L.)

BackgroundIsolated microspore culture is a useful biotechnological technique applied in modern plant breeding programs as it can produce doubled haploid (DH) plants and accelerate the development of new varieties. Furthermore, as a single-cell culture technique, the isolated microspore culture provides an excellent platform for studying microspore embryogenesis. However, the reports on isolated microspore culture are rather limited in rice due to the low callus induction rate, poor regeneration capability, and high genotypic dependency. The present study developed an effective isolated microspore culture protocol for high-frequency androgenesis in four japonica rice genotypes. Several factors affecting the isolated microspore culture were studied to evaluate their effects on callus induction and plantlet regeneration.ResultsLow-temperature pre-treatment at 4 ℃ for 10–15 days could effectively promote microspore embryogenesis in japonica rice. A simple and efficient method was proposed for identifying the microspore developmental stage. The anthers in yellow-green florets located on the second type of primary branch on the rice panicle were found to be the optimal stage for isolated microspore culture. The most effective induction media for callus induction were IM2 and IM3, depending on the genotype. The optimal concentration of 2, 4-D in the medium for callus induction was 1 mg/L. Callus induction was negatively affected by a high concentration of KT over 1.5 mg/L. The differentiation medium suitable for japonica rice microspore callus comprised 1/2 MS, 2 mg/L 6-BA, 0.5 mg/L NAA, 30 g/L sucrose, and 6 g/L agar. The regeneration frequency of the four genotypes ranged from 61–211 green plantlets per 100 mg calli, with Chongxiangjing showing the highest regeneration frequency.ConclusionsThis study presented an efficient protocol for improved callus induction and green plantlet regeneration in japonica rice via isolated microspore culture, which could provide valuable support for rice breeding and genetic research.

Effects of a New Plant Growth Regulator on Callus Induction from Immature Embryo Explants of Korean Pine (Pinus koraiensis)

Somatic embryogenesis is currently the most promising technique for the large-scale production and breeding of conifer species. Nonetheless, the low explant induction rate in this process hampers the development of improved materials. In this study, three immature Korean pine (Pinus koraiensis) embryos capable of induction were used as experimental materials. Various concentrations of brassinolide (BL), melatonin (Mel), salicylic acid (SA), glutathione (GSH), and ascorbic acid (AsA) were added to induce embryogenic callus tissue. The results show that BL had the most significant positive effect on promoting induction and increasing explant survival. Mel was also found to slightly increase the induction and survival rates of explants. When 1.00 mg·L−1 BL was added to the explants derived from stock tree I, which had strong self-induction ability, for 30 days, the callus induction rate rose to 400% compared to the control group. Following the addition of 25 mg·L−1 Mel to stock tree I for 30 days, the callus induction rate further increased to 450% of the control group. The effect of GSH on callus induction was insignificant. The addition of 0.10 g·L−1 to stock tree I for 30 days resulted in only a 150% higher induction rate compared to the control group. When 1.00 mg·L−1 BL was applied to explants with weak self-induction ability (stock tree III) for 15 days, the callus induction rate increased to 600% of that of the control group. The callus induction rate further increased to 800% of the control group after 50 mg·L−1 BL were added to stock tree III for 15 days. This study presents a method to improve the induction of embryogenic callus tissue in Korean pine.

Simultaneous production of high-frequency synthetic apomixis with high fertility and improved agronomic traits in hybrid rice

The current apomixis system used in fixing heterozygosity suffers from the problems of low fertility and limited apomixis induction rate. This study implies that egg-cell-specific expression of dandelion's PAR combined with MiMe in hybrid rice can efficiently trigger highly fertile synthetic apomixis for effective clonal propagation of hybrids.

Ultra-small radiosensitizers deliver epigenetic drugs to induce pyroptosis and boost triple-negative breast cancer radiotherapy

The pyroptosis of tumor cells can elicit a potent anti-tumor immune response, offering a promising approach to the therapy of triple-negative breast cancer (TNBC) and the prevention of tumor recurrence and metastasis. This study developed a nanocomposite system of ultra-small hafnium oxide nanoparticles (HfO2 NPs) loaded with Decitabine (DAC) to effectively transform radiation-induced tumor cell apoptosis into pyroptosis. Initially, DAC was delivered efficiently to the tumor tissues, owing to the well tumor osmosis and retention of HfO2 NPs. Furthermore, HfO2 NPs can generate more reactive oxygen species to activate Caspase-3 upon ionizing radiation. Ultimately, DAC can effectively suppress DNA methyltransferase, reverse the silencing state of GSDME in TNBC cells, and convert apoptosis into pyroptosis. Pyroptosis can activate more powerful anti-tumor immunity and effectively inhibit tumor metastasis. This study not only addresses the concerns of significant side effects and low induction rate of conventional pyroptosis-inducing drugs but also provides a novel strategy for the treatment of malignancies with low GSDME expression and extends the application of pyroptosis.

The birth center model of care: Staffing, business characteristics, and core clinical outcomes.

Interest in expanding access to the birth center model is growing. The purpose of this research is to describe birth center staffing models and business characteristics and explore relationships to perinatal outcomes. This descriptive analysis includes a convenience sample of all 84 birth center sites that participated in the AABC Site Survey and AABC Perinatal Data Registry between 2012 and 2020. Selected independent variables include staffing model (CNM/CM or CPM/LM), legal entity status, birth volume/year, and hours of midwifery call/week. Perinatal outcomes include rates of induction of labor, cesarean birth, exclusive breastfeeding, birthweight in pounds, low APGAR scores, and neonatal intensive care admission. The birth center model of care is demonstrated to be safe and effective, across a variety of staffing and business models. Outcomes for both CNM/CM and CPM/LM models of care exceed national benchmarks for perinatal quality with low induction, cesarean, NICU admission, and high rates of breastfeeding. Within the sample of medically low-risk multiparas, variations in clinical outcomes were correlated with business characteristics of the birth center, specifically annual birth volume. Increased induction of labor and cesarean birth, with decreased success breastfeeding, were present within practices characterized as high volume (>200 births/year). The research demonstrates decreased access to the birth center model of care for Black and Hispanic populations. Between 2012 and 2020, 84 birth centers across the United States engaged in 90,580 episodes of perinatal care. Continued policy development is necessary to provide risk-appropriate care for populations of healthy, medically low-risk consumers.

Regional practice variation in induction of labor in the Netherlands: Does it matter? A multilevel analysis of the association between induction rates and perinatal and maternal outcomes.

Practice variation in healthcare is a complex issue. We focused on practice variation in induction of labor between maternity care networks in the Netherlands. These collaborations of hospitals and midwifery practices are jointly responsible for providing high-quality maternity care. We explored the association between induction rates and maternal and perinatal outcomes. In a retrospective population-based cohort study, we included records of 184,422 women who had a singleton, vertex birth of their first child after a gestation of at least 37 weeks in the years 2016-2018. We calculated induction rates for each maternity care network. We divided networks in induction rate categories: lowest (Q1), moderate (Q2-3) and highest quartile (Q4). We explored the association of these categories with unplanned caesarean sections, unfavorable maternal outcomes and adverse perinatal outcomes using descriptive statistics and multilevel logistic regression analysis corrected for population characteristics. The induction rate ranged from 14.3% to 41.1% (mean 24.4%, SD 5.3). Women in Q1 had fewer unplanned caesarean sections (Q1: 10.2%, Q2-3: 12.1%; Q4: 12.8%), less unfavorable maternal outcomes (Q1: 33.8%; Q2-3: 35.7%; Q4: 36.3%) and less adverse perinatal outcomes (Q1: 1.0%; Q2-3: 1.1%; Q4: 1.3%). The multilevel analysis showed a lower unplanned caesarean section rate in Q1 in comparison with reference category Q2-3 (OR 0.83; p = .009). The unplanned caesarean section rate in Q4 was similar to the reference category. No significant associations with unfavorable maternal or adverse perinatal outcomes were observed. Practice variation in labor induction is high in Dutch maternity care networks, with limited association with maternal outcomes and no association with perinatal outcomes. Networks with low induction rates had lower unplanned caesarean section rates compared to networks with moderate rates. Further in-depth research is necessary to understand the mechanisms that contribute to practice variation and the observed association with unplanned caesarean sections.

Naringenin Impedes the Differentiation of Mouse Hematopoietic Stem Cells Derived from Bone Marrow into Mature Dendritic Cells, thereby Prolonging Allograft Survival.

The use of immature dendritic cells (imDCs) to induce donor-specific immunotolerance following in vivo stimulation is limited by their low rate of induction and their tendency to undergo maturation. We derived imDCs from bone marrow hematopoietic stem cells (HSCs-imDCs). We then tested the ability of naringenin (Nar) to impede the maturation of HSCs-imDCs for inducing transplantation immune tolerance. HSCs derived from bone marrow were collected and induced to differentiate into imDCs by treating with Nar (Nar-HSCs-imDCs). Flow cytometry was used to evaluate DC surface markers, apoptosis, and endocytic ability. The ability of DCs to influence the in vitro proliferation of T cells and of regulatory T cells (Tregs) was analyzed by mixed lymphocyte reaction assays. Enzyme-linked immunoassays were used to quantify cytokine levels in supernatants from co-cultured DCs and Tregs, as well as in the serum of experimental animals. The level of immunotolerance induced by Nar-HSCs-imDCs was evaluated by skin grafting in recipient Balb/c mice, while the Kaplan-Meier method was used to statistically evaluate graft survival. Compared with HSC-imDCs, Nar-HSCs-imDCs showed higher expression of cluster of differentiation 11c (CD11c), but lower expression levels of CD80, CD86, and major histocompatibility complex class II. Nar-HSCs-imDCs also showed stronger inhibition of T cells and higher Treg cell proliferation. Interleukin 2 (IL-2) and interferon gamma levels were downregulated in Nar-HSCs-imDCs, whereas IL-4, IL-10, and transforming growth factor beta levels were upregulated. The rate of apoptosis and endocytic capacity of Nar-HSCs-DCs increased significantly after treatment with lipopolysaccharide. HSCs-imDCs or Nar-HSCs-imDCs were injected into Balb/c mice via the tail vein 7 days before skin grafting. Significantly reduced donor-specific CD4+ T cells and induced proliferation of CD4+CD25+FoxP3+ Treg cells were observed in the spleen of mice from the Nar-HSCs-imDCs group, especially at a dose of 106 Nar-HSCs-imDCs. The latter group also showed significantly prolonged survival of skin grafts. Nar-HSCs-imDCs markedly improved the acceptance of organ allografts, offering a potentially new strategy for inducing immune tolerance in transplantation.

Protocol optimization and assessment of genotypic response for inbred line development through doubled haploid production in maize

BackgroundDoubled haploid technology offers the fastest route of inbred line development by rapidly fixing the desirable combinations in a single year. However, the differential response of haploid induction to genetic background of maternal lines accompanied with low induction rate and high mortality rate due to artificial chromosomal doubling of haploid seedlings creates hindrance in doubled haploid production on a commercial scale under tropical conditions. To speed up the hybrid breeding programme in sub-tropical maize, efforts are reported here to optimize the protocol for efficient production of fixed lines using haploid inducers. The second-generation haploid inducers i.e. CIM2GTAILs obtained from CIMMYT, Mexico were used for haploid induction in 13 F1s of diverse backgrounds. For standardization of chromosomal doubling protocol, various concentrations of colchicine and two seedling growth stages were used to determine the extent of chromosomal doubling and survival rate of doubled haploid plants.ResultsA high mean haploid induction rate is obtained from CIM2GTAIL P2 (10%) as compared to CIM2GTAIL P1 (7.46%). Out of four treatments, CIMMYT reported protocol of chromosome doubling in tropical maize comprising combination of 0.07% colchicine and 0.1% DMSO at V2 stage is highly effective for acquiring doubled haploid plants in sub-tropical adapted maize with high survival rate of 52.7%. However, increasing the colchicine concentration from 0.07 to 0.1% led to high mortality rate.ConclusionAccording to the findings, the haploid induction rate, survival rate and overall success rate varied depending upon the genotype of the inducer and the source population along with the concentrations of chemical used. The optimized protocol developed using CIMMYT haploid inducer CIM2GTAIL P2 for efficient doubled haploid production will not only fasten the breeding programme but will also reduce the production cost of doubled haploid with great efficiency in sub-tropical maize.

Development of In Vitro Anther Culture for Doubled Haploid Plant Production in Indica Rice (Oryza sativa L.) Genotypes.

Anther culture is an efficient biotechnological tool in modern plant breeding programs to produce new varieties and parental lines in hybrid seed productions. However, some bottlenecks-low induction rate, genotype dependency, albinism-restrict the widespread utilization of in vitro anther culture in rice breeding, especially in Oryza sativa ssp. indica (indica) genotypes, while an improved efficient protocol can shorten the process of breeding. Three different induction media (N6NDK, N6NDZ, Ali-1) and four plant regeneration media (mMSNBK1, MSNBK3, MSNBKZ1, MSNBKZ2) were tested with five indica rice genotypes to increase the efficiency of in vitro androgenesis (number of calli and regenerated green plantlets). The production of calli was more efficient on the N6NDK medium with an average 88.26 calli/100 anthers and N6NDZ medium with an average of 103.88 calli/100 anthers as compared to Ali-1 with an average of 6.96 calli/100 anthers. The production of green plantlets was greater when calli was produced on N6NDK medium (2.15 green plantlets/100 anthers) compared when produced on to N6NDZ medium (1.18 green plantlets/100 anthers). Highest green plantlets production (4.7 green plantlets/100 anthers) was achieved when mMSNBK1 plant regeneration medium was used on calli produced utilizing N6NDK induction medium. In the best overall treatment (N6NDK induction medium and mMSNBK1 plant regeneration medium), four tested genotypes produced green plantlets. However, the genotype influenced the efficiency, and the green plantlets production ranged from 0.4 green plantlets/100 anthers to 8.4 green plantlets/100 anthers. The ploidy level of 106 acclimatized indica rice plantlets were characterized with flow cytometric analyses to calculate the percentage of spontaneous chromosome doubling. Altogether, 48 haploid-, 55 diploid-, 2 tetraploid- and 1 mixoploid plantlets were identified among the regenerant plantlets, and the spontaneous chromosome doubling percentage was 51.89%. Utilization of DH plants have been integrated as a routine method in the Hungarian rice breeding program. The tetraploid lines can be explored for their potential to offer new scopes for rice research and breeding directions in the future.

Optimization of Key Technologies for Induction of Embryogenic Callus and Maturation of Somatic Embryos in Korean Pine (Pinus koraiensis)

Somatic embryogenesis (SE), which leads to the formation of embryonic callus (EC) tissue, is the most promising method for large-scale production and selective breeding of woody plants. However, in many species, SE suffers from low induction and proliferation rates, hindering the production of improved plant materials. We investigated the effects of the explant sterilization method, 4 °C cryopreservation, basal medium, ethylene removal, liquid medium supplementation, and a combination of PGRs on embryogenic callus (EC) induction of Korean pine, using immature embryos of Korean pine as explants. The effects of sucrose and maltose on EC proliferation and maturation were investigated. The differences in the maturation ability of EC somatic embryos before and after cryopreservation were evaluated using the induced embryonic cell lines. The results showed that zygotic embryos (ZEs) performed better than megagametophytes (MGs) as explants. The induction rate of EC was significantly increased after 28 days of cryopreservation at 4 °C. The induction rate of EC in the #5 family increased from 10.00% to 62.8%. The EC induction rate of the five families cultured with the DCR basal medium was higher than that with the mLV basal medium. Among them, the induction rate of the #5 family cultured with the mLV basal medium was 23.3%, while that with the DCR basal medium was 60.9%, an increase of 2.6 times. There was no significant difference in the maturation ability of EC somatic embryos before and after cryopreservation. In conclusion, this study provides a method to improve the EC induction rate and maturation ability of Korean pine.

Genome-Wide Identification of Homeodomain Leucine Zipper (HD-ZIP) Transcription Factor, Expression Analysis, and Protein Interaction of HD-ZIP IV in Oil Palm Somatic Embryogenesis

Understanding the molecular mechanisms underlying somatic embryogenesis is essential for resolving the problems related to the long duration of the process and a low rate of somatic embryo induction in oil palm tissue culture. In this study, we conducted genome-wide identification of the oil palm homeodomain leucine zipper (EgHD-ZIP) family, which is one of the plant-specific transcription factors reported to be involved in embryogenesis. EgHD-ZIP proteins can be divided into four subfamilies, which have similarities in gene structure and protein-conserved motifs within a group. In silico expression analysis showed that the expression of EgHD-ZIP gene members in the EgHD-ZIP I and II families, as well as most members in the EgHD-ZIP IV family, were up-regulated during the zygotic and somatic embryo developmental stages. In contrast, the expression of EgHD-ZIP gene members in the EgHD-ZIP III family was down-regulated during zygotic embryo development. Moreover, the expression of EgHD-ZIP IV genes was validated in the oil palm callus and at the somatic embryo stages (globular, torpedo, and cotyledon). The results revealed that EgHD-ZIP IV genes were up-regulated at the late stages of somatic embryogenesis (torpedo and cotyledon). While BABY BOOM (BBM) gene was up-regulated at the early stage of somatic embryogenesis (globular). In addition, the Yeast-two hybrid assay revealed the direct binding between all members of the oil palm HD-ZIP IV subfamily (EgROC2, EgROC3, EgROC5, EgROC8, and EgBBM). Our findings suggested that the EgHD-ZIP IV subfamily and EgBBM work together to regulate somatic embryogenesis in oil palms. This process is important because it is widely used in plant biotechnology to produce large quantities of genetically identical plants, which can be used for oil palm tissue culture improvement.

Rational design of stapled antimicrobial peptides.

The global increase in antimicrobial drug resistance has dramatically reduced the effectiveness of traditional antibiotics. Structurally diverse antibiotics are urgently needed to combat multiple-resistant bacterial infections. As part of innate immunity, antimicrobial peptides have been recognized as the most promising candidates because they comprise diverse sequences and mechanisms of action and have a relatively low induction rate of resistance. However, because of their low chemical stability, susceptibility to proteases, and high hemolytic effect, their usage is subject to many restrictions. Chemical modifications such as D-amino acid substitution, cyclization, and unnatural amino acid modification have been used to improve the stability of antimicrobial peptides for decades. Among them, a side-chain covalent bridge modification, the so-called stapled peptide, has attracted much attention. The stapled side-chain bridge stabilizes the secondary structure, induces protease resistance, and increases cell penetration and biological activity. Recent progress in computer-aided drug design and artificial intelligence methods has also been used in the design of stapled antimicrobial peptides and has led to the successful discovery of many prospective peptides. This article reviews the possible structure-activity relationships of stapled antimicrobial peptides, the physicochemical properties that influence their activity (such as net charge, hydrophobicity, helicity, and dipole moment), and computer-aided methods of stapled peptide design. Antimicrobial peptides under clinical trial: Pexiganan (NCT01594762, 2012-05-07). Omiganan (NCT02576847, 2015-10-13).

Fetal-Maternal Outcomes of Induction of Labour Among Women Delivered at Regional Referral Hospitals In Dar Es Salaam Tanzania

Purpose: Africa has a very low rate of induction of labour with high maternal and perinatal morbidity and mortality. However fetal-maternal outcomes following induction of labour are not well documented in Tanzania. This study aimed to assess fetal-maternal outcomes following induction of labour among women delivered at Dar es Salaam regional referral hospitals in Tanzania.
 Design/methodology/Approach: A total of 301 expectant mothers were recruited in a prospective observational study conducted at all regional referral hospitals in Dar es Salaam, Tanzania. Data on fetal-maternal outcomes were collected using a pre-designed clinical sheet. Demographic data, obstetric history, methods as well as outcomes of labour induction were recorded. The continuous variables were summarized using the median and corresponding interquartile range. Categorical variables were summarized using frequency and proportions and the significance of differences were assessed using Chi-square at P<0.05.
 Results: The leading methods for induction of labour were Oxytocin (48.5%) and a combination of Folley’s catheter with Oxytocin (28.4%). Induction of labour significantly improved fetal outcomes at birth P<0.05. Induction of labour associated with improved Apgar scores in newborn babies. Failure of induction of labour was the largest contributor to the increased Caesarean Section rate observed in this study.
 Research limitation/Implication: This study has therefore explored the fetal-maternal outcomes following induction of labour in Tanzanian regional referral hospitals.
 Practical implication: Induction of labour improves and minimizes neonatal complications in referral regional hospitals in Dar es Salaam.
 Originality/Value: These findings fill a gap of information which was missing on the fetal-maternal outcomes following induction of labour among expectant mothers in Dar es Salaam regional referral hospitals.

Conjugation of Ctx(Ile21)-Ha Antimicrobial Peptides to Chitosan Ultrathin Films by N-Acetylcysteine Improves Peptide Physicochemical Properties and Enhances Biological Activity

The importance of obtaining new compounds with improved antimicrobial activity is a current trend and challenge. Some polymers such as chitosan have shown promising bactericidal properties when they are structurally modified, which is due to the binding versatility provided by their free amines. Likewise, antimicrobial peptides (AMPs) have received attention in recent years because of their bactericidal activity that is similar to or even better than that of conventional drugs, and they exhibit a low induction rate of antimicrobial resistance. Herein, the modified AMP Ctx(Ile21)-Ha-Ahx-Cys was conjugated to chitosan using N-acetylcysteine as an intermediate by the carbodiimide method. Films were prepared using protonated chitosan in 1% acetic acid and Ctx(Ile21)-Ha-Ahx-Cys AMP dissolved in N-acetylcysteine-chitosan; 1.6 mmol of ethylcarbodiimide hydrochloride, 1.2 mmol of N-hydroxysulfosucchimide, and 0.1 mol L –1of N-morpholino)ethanesulfonic acid buffer at pH 6.5 by continuous stirring at 100 × g for 10 min at 37 °C. Physicochemical properties were evaluated by Fourier-transform infrared spectroscopy, differential scanning calorimetry/thermogravimetric analysis, and X-ray diffraction to determine the mechanical properties, solubility, morphology, and thickness. Furthermore, the antimicrobial activities of chitosan-based conjugated films were evaluated againstStaphylococcus aureus,Pseudomonas aeruginosa,SalmonellaTyphimurium, andEscherichia coli. The results showed that the conjugation of a potent AMP could further increase its antibacterial activity and maintain its stable physicochemical properties. Therefore, the developed peptide–chitosan conjugate could be applied as an additive in surgical procedures to prevent and combat bacterial infection.

The Effect of Anti-browning Agent Activated Carbon and Polyvinyl Pyrrolidone on the Rooting of Embryo Seedlings of "FengDan" and Its Transcriptome Analysis.

Peony is an excellent ornamental, medicinal, and oily plant. Its traditional seed propagation methods have the disadvantages of low propagation coefficient, long seedling cycle, and low seedling emergence rate, which severely restrict the supply of seedlings for the peony industry. Efficient tissue culture technology is an important basis for accelerating its breeding and reproduction, and in vitro seed embryo culturing into seedlings can also effectively avoid the above problems. However, the browning phenomenon caused by man-made damage in the process of seed embryo stripping leads to problems such as low induction rate and difficulty in rooting, and the relationship between anti-browning agents and seed embryo root formation is still unclear. This study intends to improve the induction rate of peony seedlings by using different anti-browning agents and different combinations and to clarify the relationship between anti-browning agents and seedling rooting using transcriptome sequencing methods. The results show that both anti-browning agents, activated carbon (AC) and polyvinyl pyrrolidone (PVP), can increase the germination rate of seed embryos. Testing with 0.9 g/L of AC showed excellent performance of peony rooting rate and seedling growth, but only AC and the combination of AC and PVP can further promote rooting development. Through transcriptome analysis, we found that the AC vs. control check (CK), AC vs. PVP, and PVP vs. AC and PVP groups have significantly more differentially expressed genes than the AC vs. AC and PVP groups. Pathway enrichment analysis shows that “phenylpropanoid biosynthesis”/“cutin, suberin, and wax biosynthesis” is significantly enriched in these groups, while the AC vs. AC and PVP groups are mainly enriched in “cytochrome P450,” indicating that AC may promote the further development of roots into seedlings by stimulating “phenylpropanoid biosynthesis” and biosynthesis of stratum cutin and suberin. This study can lay the foundation for understanding the potential molecular mechanism of the anti-browning agent promoting the rooting of seed embryo seedlings and also provide a theoretical basis for perfecting the construction of the peony tissue culture and rapid propagation system.

CLINICAL MANIFESTATIONS AND SAFETY OF AN ORAL FOOD CHALLENGE USING BOILED EGG YOLK

Allergenicity to heated egg yolks is known to be low in hen's egg allergy. However, there are few reports concerning the safety of an oral food challenge (OFC) with boiled egg yolks. This study aimed to determine the safety of a boiled egg yolk OFC and the clinical characteristics of patients who were OFC-positive. We retrospectively examined the data of patients who underwent an OFC with one boiled egg yolk at Miyagi Children's Hospital between January 2013 and December 2020. Patients were included if they had a history of immediate symptoms due to hen's egg or positive specific IgE levels to egg yolk or egg white. Among 600 patients, 15.0% were positive for OFC, only one patient required an intramuscular adrenaline injection, and 70% of OFC-positive patients had gastrointestinal symptoms. Boiled egg yolk OFC had a low symptom induction rate; however, when symptoms were induced, gastrointestinal symptoms were most commonly observed. Given the low risk of developing severe symptoms, we conclude that the likelihood of safely performing an OFC is high.