Precision targeting tumor cells using cancer-specific InDel mutations with CRISPR-Cas9.

An ideal cancer therapeutic strategy involves the selective killing of cancer cells without affecting the surrounding normal cells. However, researchers have failed to develop such methods for achieving selective cancer cell death because of shared features between cancerous and normal cells. In this study, we have developed a therapeutic strategy called the cancer-specific insertions-deletions (InDels) attacker (CINDELA) to selectively induce cancer cell death using the CRISPR-Cas system. CINDELA utilizes a previously unexplored idea of introducing CRISPR-mediated DNA double-strand breaks (DSBs) in a cancer-specific fashion to facilitate specific cell death. In particular, CINDELA targets multiple InDels with CRISPR-Cas9 to produce many DNA DSBs that result in cancer-specific cell death. As a proof of concept, we demonstrate here that CINDELA selectively kills human cancer cell lines, xenograft human tumors in mice, patient-derived glioblastoma, and lung patient-driven xenograft tumors without affecting healthy human cells or altering mouse growth.

Efficacy of the enhanced recovery after surgery protocol on reducing surgical disparities related to overweight/obesity in deep inferior epigastric perforator flap breast reconstruction.

BACKGROUND: When choosing a method of deep inferior epigastric perforator (DIEP) flap for breast reconstruction, concerns regarding the potentially detrimental effects of obesity on postoperative recovery remain. Enhanced recovery after surgery (ERAS) is known to facilitate rapid postoperative recovery. This study aimed to examine the effect of the ERAS protocol on the disparity between normal/underweight and overweight/obese patients after DIEP flap breast reconstruction. METHODS: A retrospective review of consecutive patients who underwent DIEP flap breast reconstruction between January 2015 and November 2022 was conducted. The patients were categorized into two groups: pre-ERAS and post-ERAS. In each group, associations between overweight/obese patients (BMI ≥25 kg/m2 ) and postoperative course were evaluated. RESULTS: In total, 217 patients in the pre-ERAS group (including 71 overweight/obese) and 165 in the post-ERAS group (including 58 overweight/obese) were analyzed. The post-ERAS group had shorter length of stay (LOS) (8.0 versus 7.0 days, p-value <.001) and lower postoperative pain scores (5.0 versus 3.0 at postoperative day (POD) 1, p-value <.001) than the pre-ERAS group. The complication profiles did not differ according to ERAS adoption. In the pre-ERAS group, overweight/obese patients showed a significantly longer LOS (8.0 versus 9.0 days, p-value = .017) and a higher postoperative pain score (3.0 versus 4.0 at POD 2, p-value = .018) than normal/underweight patients; however, these differences disappeared in the post-ERAS group, showing similar LOS, pain scores, and analgesic consumption. CONCLUSIONS: Implementation of the ERAS protocol in DIEP free-flap breast reconstruction may reduce overweight/obesity-related disparities in postoperative recovery.

"Strategic Application of Anatomical Subunit Approximation Technique for Correction of Complete Unilateral Cleft lip".

OBJECTIVE: To discuss advantages, disadvantages and strategical application of anatomical subunit approximation technique in complete unilateral cleft lip repair. DESIGN: Analysis of consecutive 28 cases. SETTING: A single surgeon experience at a university hospital. PATIENTS: Among 77 patients who underwent cleft lip repair between May 5, 2019 and June 30, 2021, 28 patients with complete unilateral cleft lip who received cheiloplasty by author's technique. MAIN OUTCOME MEASURES: Surgical outcomes were assessed by frontal view medical photographs obtained postoperatively at follow-up visits. RESULTS: The average length difference between cleft and noncleft sides was <10% for transverse lip length and philtral height. Nostril sill height demonstrated about twenty percent of difference with much variable results. Although the one sample t-test revealed that differences exist between the cleft and noncleft side, they were within an acceptable range. CONCLUSIONS: Understanding the strengths and limitations of anatomical subunit approximation technique enabled strategic application in complete unilateral cleft lip repair. Satisfactory outcomes were achieved not only regarding the scar placement but also regarding the symmetry of the lips and augmentation of nasal sill.

Predictors for Implant Rupture in Two-Stage Tissue Expander-Based Breast Reconstruction: A Retrospective Cohort Study.

BACKGROUND: Two-stage tissue expander/implant-based method has been used predominantly for breast reconstruction. Implant rupture is one of the bothersome complications, inducing additional morbidity including reoperation. The present study aimed to identify the independent factors associated with development of implant rupture. PATIENTS AND METHODS: Patients who underwent immediate two-stage prosthetic breast reconstruction between 2010 and 2016 were reviewed. Inserted implants were followed up using magnetic resonance imaging every 2 years and/or ultrasound/computed tomography scans every 6 or 12 months that were conducted for cancer surveillance. Associations of perioperative and intraoperative variables with the development of implant rupture were evaluated. RESULTS: In total, 797 cases (744 patients) were analyzed. During a median follow-up of 43 months after second-stage operation, implant rupture was identified in 22 cases. The 5-year cumulative incidence was 3.1%. Multivariable analyses showed that the interval between the first- and second-stage operations was inversely associated with the risk of implant rupture. Maximal discrimination was observed at the interval of 6.5 months. Cases with an interval ≤ 6 months were associated with higher risks for implant rupture than those with ≥ 7 months, after adjusting for other variables. Type of implant was associated with the development of implant rupture, showing that using two kinds of fourth-generation implant (Allergan Biocell textured round and Allergan smooth round implants) was associated with a significantly increased risk of implant rupture compared with that of Mentor MemoryShape implants (fifth-generation implant). CONCLUSION: Several operation-related variables appear to be associated with implant rupture in two-stage prosthetic reconstruction.

Adjuvant Chemotherapy in Two-Stage Tissue Expander/Implant Breast Reconstruction: Does it Affect Final Outcomes?

BACKGROUND: In immediate two-stage implant-based breast reconstruction, adjuvant chemotherapy, when indicated, is usually conducted between the stages, which might influence the outcomes of the second-stage operation. OBJECTIVE: The purpose of this study was to evaluate the potential influence of adjuvant chemotherapy on the final outcomes of two-stage implant-based reconstructions. METHODS: Patients who underwent immediate tissue expander/implant breast reconstruction between 2010 and 2016, with completion of both stages, were reviewed. Cases were categorized into two groups-adjuvant chemotherapy and no adjuvant chemotherapy. The rates of adverse outcomes were compared between the groups. RESULTS: A total of 602 cases in 568 patients were analyzed, with a mean follow-up period of 58.5 months, including 236 patients receiving adjuvant chemotherapy and 366 patients not receiving adjuvant chemotherapy. The two groups had similar baseline characteristics, except for a significantly higher rate of adjuvant radiotherapy in the former group. The adjuvant chemotherapy group showed significantly higher rates of overall complications (odds ratio [OR] 2.127, 95% confidence interval [CI] 1.231-3.676), including infections (OR 4.239, 95% CI 1.059-16.970), severe capsular contractures (OR 2.107, 95% CI 1.067-4.159), and reconstruction failures (OR 12.754, 95% CI 1.587-102.481) compared with the control group, after adjusting for other variables, including adjuvant radiotherapy. In the analysis regarding the influence of chemotherapy regimens, the use of sequential anthracycline/cyclophosphamide and taxane, and concurrent 5-fluorouracil, doxorubicin and cyclophosphamide, were associated with increased risks for adverse outcomes compared with the no chemotherapy group, while the use of other regimens, including anthracycline/cyclophosphamide alone, was not. CONCLUSIONS: Adjuvant chemotherapy might influence the final outcomes of two-stage implant-based reconstruction.

Genetic Diversity and Distribution of Korean Isolates of Burkholderia glumae.

Burkholderia glumae causes panicle blight of rice (grain rot in Japan and Korea), and the severity of damage is increasing worldwide. During 2017 and 2018, 137 isolates of B. glumae were isolated from symptomatic grain rot of rice cultivated in paddy fields throughout South Korea. Genetic diversity of the isolates was determined using transposase-based PCR (Tnp-PCR) genomic fingerprinting. All 138 isolates, including the B. glumae BGR1 strain, produced toxoflavin in various amounts, and 17 isolates produced an unidentified purple or orange pigment on Luria-Bertani medium and casamino acid-peptone-glucose medium, respectively, at 28°C. Transposase-based PCR genomic fingerprinting was performed using a novel primer designed based on transposase (tnp) gene sequences located at the ends of the toxoflavin efflux transporter operon; this method provided reliable and reproducible results. Through Tnp-PCR genomic fingerprinting, the genetic groups of Korean B. glumae isolates were divided into 11 clusters and three divisions. The Korean B. glumae isolates were mainly grouped in division I (73%). Interestingly, most of the pigment-producing isolates were grouped in divisions II and III; of these, 10 were grouped in cluster VIII, which comprised 67% of this cluster. Results of a phylogenetic analysis based on tofI and hrpB gene sequences were consistent with classification by Tnp-PCR genomic fingerprinting. The BGR1 strain did not belong to any of the clusters, indicating that this strain does not exhibit the typical genetic representation of B. glumae. B. glumae isolates showed diversity in the use of carbon and nitrogen sources, but no correlation with genetic classification by PCR fingerprinting was found. This is the first study to analyze the geographical distribution and genetic diversity of Korean B. glumae isolates.

Regional Lymph Node Metastasis of Scalp Angiosarcoma: A Detailed Clinical Observation Study of 40 Cases.

BACKGROUND: The incidence of lymph node metastasis (LNM) of angiosarcomas is reported to be less than 15%, and elective neck management has not been indicated. This study evaluated the incidence and pattern of regional LNM in patients with scalp angiosarcomas using the clinical data of its full course to understand time-event sequences of scalp angiosarcomas. METHODS: This retrospective study included all consecutive cases of pathology-confirmed angiosarcomas and analyzed 40 cases of scalp angiosarcomas. The survival plots were estimated using the Kaplan-Meier method, and the results are presented mainly in a descriptive manner. RESULTS: The overall survival rate for the patients was 35.8% at 2 years. In contrast to previous reports, regional LNM was observed in more than half of the patients (52.5%) with scalp angiosarcoma. Meanwhile, a direct spread to distant organs occurred in only 27.5% of the patients. Regional LNM could predict clinical manifestation of systemic disease within 3 to 6 months. No differences in survival rates between patients with and without LNM were observed in this series. Occurrence of LNM seemed to be correlated with a high mitotic rate of primary tumors, but not with tumor grade or tumor dimension. The first-echelon lymph nodes from scalp angiosarcoma were peri-parotid, post-auricular, and level 2 lymph nodes. CONCLUSIONS: For a localized scalp angiosarcoma, it seems reasonable for initial curative surgery to include prophylactic evaluation of regional lymph nodes for pathologic nodal staging, prognosis estimation, and the decision for systemic treatments.

Internal Fixation Method Using EZ-Tcon for Transconjunctival Fat Repositioning: Clinical Outcomes and Efficacy.

BACKGROUND: Transconjunctival fat repositioning is the gold standard for the correction of tear trough deformity. For fixation of fat pedicle, the internal fixation (IF) and externalized percutaneous suture (EPS) techniques are used, which have their own advantages and disadvantages. The present study aimed to introduce a new IF technique using a devised needle (EZ-Tcon) and to compare its outcomes with those of the conventional EPS technique. METHODS: Patients with primary tear trough deformity who underwent transconjunctival fat repositioning were reviewed and categorized into two cohorts according to the fixation technique: cohort 1 consisted of patients treated using the conventional EPS technique and cohort 2 consisted of those in whom the new IF technique using EZ-Tcon was adopted. Post-operative complications and aesthetic outcomes were assessed using a four-scale grading system. RESULTS: A total of 545 patients, 211 from cohort 1 and 344 from cohort 2 were evaluated with a median follow-up of 70 days. Compared to cohort 1, cohort 2 showed significantly lower rates of long-standing conspicuous scars on lower eyelid, re-operation and overall complications. In the analysis of aesthetic outcomes, 88.9 percent of cohort 2 showed grade 0 (no deformity) or I (mild deformity) post-operatively. The rate of excellent outcomes (improvements of ≥ two grades) was significantly higher in cohort 2 than in cohort 1 (p-value < 0.001). CONCLUSION: Our technique using EZ-Tcon could possess advantages of the conventional IF and EPS techniques, showing lower complication rates and aesthetically satisfactory outcomes, and could be a safe and reliable method of transconjunctival fat repositioning. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Predictors, management and prognosis of initial hyperemia of free flap.

In free flap operation, temporary hyperemia of the transferred flaps can often be encountered in the early postoperative period, appearing reddish and rapid capillary refilling time, which mimics venous congestion. This study aimed to investigate the factors associated with the development of hyperemia and evaluate clinical course. Consecutive patients who underwent free flap-based reconstruction between December 2019 and October 2021 were reviewed. Independent risk factors associated with its development were assessed. Flap showing initial hyperemic features were assessed using flap blood glucose measurement (BGM). If it showed over 60 mg/dL, they were closely observed without management. Their clinical outcomes were evaluated. In total, 204 cases were analyzed, of which 35 (17.2%) showed initial hyperemia. Multivariable analyses showed that using thoracodorsal artery perforator flaps and muscle containing flaps (musculocutaneous/muscle-chimeric flaps) and conducting end-to-end arterial anastomosis (vs. end-to-side) were independent predictors. All cases with initial hyperemia showed over 60 mg/dL in BGM. The phenomenon resolved spontaneously within 6.9 h averagely. Overall perfusion-related complications developed in 10 (4.9%) cases, which rate did not differ between the two groups. Several factors might be associated with the development of initial hyperemia after free flap surgery. With proper assessment, this condition can be successfully managed without unnecessary intervention.

Neuronal AMPK regulates lipid transport to microglia.

In neurodegeneration, neurons release lipids that accumulate in glial lipid droplets (LDs). But what controls lipid transport and how does this affect glia? A recent study by Li et al. discovered that the loss of neuronal AMP-activated protein kinase (AMPK) activity promotes lipid efflux, which drives a proinflammatory state in microglia.

Surgical Treatment of Enlarged Cervical Leiomyoma with Concomitant Uterine Prolapse: A Case Report.

This case report details the surgical treatment of a rare enlarged cervical leiomyoma with uterine prolapse in a 48-year-old woman. She presented to Konyang University Hospital with a palpable vaginal mass, lower abdominal pain, and urinary incontinence. Despite being nulliparous, she had severe chronic constipation due to schizophrenia medication and lived in a health care facility separated from her family. Pelvic examination revealed stage 3 uterine prolapse with a large necrotic cervical leiomyoma. A robot-assisted vaginal hysterectomy followed by sacrocolpopexy was performed using the Da Vinci Xi Surgical System. Histopathology confirmed cervical leiomyoma with squamous metaplasia. At a three-month follow-up, there were no complications, pelvic anatomy was restored, and urinary incontinence improved. Although the patient had a systemic infection due to the necrotic cervical leiomyoma, raising concerns about the increased risk of infection associated with mesh use, she was high-risk for pelvic organ prolapse (POP) recurrence due to her medical history and living situation. Therefore, she underwent concurrent surgeries with pre- and postoperative antibiotic treatment, and recovered without complications. Given that the risk of developing POP increases after a hysterectomy, in high-risk patients, as demonstrated in this case, the concurrent surgical correction of POP may be an effective strategy.

Impact of Initial Filling Medium on Outcomes of Subpectoral, Two-Stage, Implant-Based Breast Reconstruction: Air versus Saline.

BACKGROUND: In two-stage expander-based breast reconstruction, the use of air as the initial filling medium has been suggested to confer clinical advantages over conventional saline, but this has not been demonstrated in a large series. This study aimed to evaluate the association between material type (air versus saline) for initial expander filling and postoperative outcomes. METHODS: This retrospective study included patients who underwent immediate, subpectoral, tissue expander-based breast reconstruction between January of 2018 and March of 2021. The participants were categorized into two groups according to the material used for initial filling: saline-inflated expanders, which were used during the first 22 months consecutively, and air-inflated expanders, which were used during the latter 17 months consecutively. Complications including mastectomy flap necrosis and postoperative expansion profiles were compared. Multivariable analyses were performed to identify independent predictors of postoperative complications. RESULTS: A total of 443 breasts (400 patients), including 161 air-filled and 282 saline-filled breasts, were analyzed. The two groups had similar baseline characteristics. The air-filled group showed a significantly lower rate of mastectomy flap necrosis; this difference remained significant after adjustment for other variables in the multivariable analysis. The rates of other complications did not differ between the two groups. The air-filled group had fewer office visits and a shorter period to complete expansion. CONCLUSIONS: The use of air for initial expander filling could provide safe and reliable outcomes with reduced patient discomfort during postoperative expansion; thus, air-filled expanders might be an effective alternative to saline-filled expanders. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Multiple intramuscular ropivacaine injections to donor sites reduces pain in deep inferior epigastric artery perforator flap breast reconstruction.

INTRODUCTION: Local anesthetic infiltration at the surgical site has been studied in various surgical disciplines; however, its impact on deep inferior epigastric artery perforator (DIEP) flap breast reconstruction has not been previously assessed. This study aimed to evaluate the effects of multiple intramuscular ropivacaine injections on donor site pain during DIEP flap breast reconstruction. METHODS: The study included 65 patients who received local ropivacaine injections during DIEP reconstructions between March 2022 and February 2023, compared to 55 patients who underwent surgeries without ropivacaine from October 2018 to July 2020. A total of 20 cc of 0.75% ropivacaine solution was evenly administered at 20 sites along the abdominal wall muscles. The effect of intramuscular ropivacaine injection on postoperative visual analog scale (VAS) was evaluated using linear mixed-effect model. Opioid consumption and hospital days were also compared. RESULTS: The daily median VAS score was lower in the ropivacaine group (all p-values < 0.001). When analyzed using a linear mixed-effects model, those who received ropivacaine had significantly lower VAS scores over the first 5 days postoperatively (p-value < 0.001). The rate of VAS score decline was also faster in the ropivacaine group over the first 24 h postoperative (p-value = 0.045). Although opioid consumption was comparable between the groups, those receiving ropivacaine had significantly shorter hospital stay (p-value = 0.001) and no complications related to the injections were observed. CONCLUSION: Multiple intramuscular injections of ropivacaine to the donor site may reduce postoperative pain and shorten hospital stays, without increasing opioid consumption.

The early postoperative effects of rinsing the breast pocket with tranexamic acid in prepectoral prosthetic breast reconstruction.

BACKGROUND: The efficacy of tranexamic acid (TXA) has been reported in breast surgery; however, its application and duration have varied across studies. This study aimed to assess the early postoperative outcomes of rinsing the breast pocket with TXA during prepectoral prosthetic breast reconstruction using an acellular dermal matrix (ADM). METHODS: A retrospective chart review was conducted in consecutive patients who underwent immediate prosthetic prepectoral reconstruction between August 2021 and December 2022. For cases performed during the earlier part of the study period (up to April 2022), TXA was not administered (non-TXA group), whereas those performed after April 2022 received topical TXA application during surgery (TXA group). Postoperative outcomes including hematoma, seroma, drainage volume, and drain maintenance duration were compared between the two groups using propensity score matching (PSM). RESULTS: A total of 674 breasts were analyzed; 280 in the TXA group and 394 were in the non-TXA group. There were 251 breasts in each group after PSM, and their characteristics were similar. The incidence of hematoma in the first 24 hours and total drain output were significantly lower in the TXA group than the non-TXA group. In cases of direct-to-implant cases, the TXA group showed a significantly lower seroma rate. CONCLUSIONS: Rinsing the breast pocket with TXA can potentially reduce the occurrence of hematoma and decrease drain output in prepectoral ADM-assisted prosthetic breast reconstruction. Moreover, this approach may be beneficial in lowering the incidence of seroma in direct-to-implant reconstruction.

Effects of Prostaglandin E1 on Mastectomy Flap Necrosis in Immediate Implant-based Breast Reconstruction.

PURPOSE: Necrosis of a cutaneous flap including the nipple-areolar complex is a common complication in immediate implant-based breast reconstruction following nipple/skin-sparing mastectomy (NSM/SSM). This study aimed to evaluate the efficacy of prostaglandin E1 (PGE1) in reducing such complications. METHODS: A retrospective analysis of prospectively collected data was conducted at two centers, and the cohort consisted of patients undergoing NSM/SSM followed by immediate reconstruction with a prosthesis. Patients who were randomly allocated to the treatment group were administered daily intravenous PGE1 (10 mcg/2 mL) beginning intraoperatively through postoperative day 6. Skin flap complications including nipple/skin necrosis, delayed wound healing, and postoperative wound revision were recorded. Complication rates were compared between the PGE1 and control groups. RESULTS: A total of 276 breasts in 259 patients were included for analysis (139 breasts to the treatment group and 137 breasts to the control group). There was no difference in patient demographics between the control and treatment group. Reconstructed breasts receiving PGE1 had significantly lower rates for overall skin complications (21.6% vs. 34.3%, p=0.022) and wound revision (2.9% vs. 9.5%, p=0.025). Among NSM cases, the PGE1 group showed a significantly lower rate of nipple necrosis (15.5% vs. 29.4%, p=0.027). In the multivariate analysis, the use of PGE1 significantly reduced the risk of overall skin flap complications (odds=0.491, p=0.018), wound revision (odds=0.213, p=0.018) in NSM/SSM cases, and nipple necrosis (odds=0.357 p=0.008) in NSM cases. CONCLUSION: PGE1 can be effective in reducing risk of mastectomy flap complications in immediate implant-based breast reconstructions.

Optimal Timing of Expander-to-Implant Exchange after Irradiation in Immediate Two-Stage Breast Reconstruction.

BACKGROUND: Time intervals for expander-to-implant exchange from radiation therapy have been reported to reduce device failure. This study investigated the optimal timing of expander-to-implant exchange after irradiation in terms of short- and long-term outcomes. METHODS: This retrospective review enrolled consecutive patients who underwent immediate two-stage breast reconstruction and radiation therapy to tissue expanders from 2010 to 2019. Receiver operating characteristic curves and the Youden index were used to estimate the optimal time from radiation therapy to implant placement in terms of 49-day (early) and 2-year (late) complications. Logistic regression analysis was performed to identify the risk factors for each complication. RESULTS: Of the 1675 patients, 133 were included. The 49-day and 2-year complication rates were 8.3 percent and 29.7 percent, respectively. Capsular contracture was the most common 2-year complication. The Youden index indicated that implant placement at 131 days after radiation therapy was most effective in reducing the 49-day complications, but that the 2-year complication was less significant, with lower sensitivity and area under the curve. Modified radical mastectomy, expander fill volume at radiation therapy, and size of permanent implant increased the odds of 49-day complications; none of them was associated with the odds of 2-year complications. CONCLUSIONS: To reduce short-term complications, the best time point for permanent implant placement was 131 days after radiation therapy. However, there was no significant time interval for reducing long-term complications. Capsular contracture was an irreversible complication of radiation injury that was not modified by postirradiation variables including the time from irradiation or size of permanent implant. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Grey mould control by oxalate degradation using non-antifungal Pseudomonas abietaniphila strain ODB36.

Grey mould is an important necrotrophic fungal pathogen that causes huge economic losses in agriculture. Many types of bacteria are used for biological control of grey mould via competition for space or nutrients and/or the production of antifungal metabolites. Oxalate is a key component of virulent necrotic fungal pathogens. In this study, we isolated non-antifungal oxalate-degrading bacteria (ODB) from the surfaces of oxalate-rich spinach and strawberries to investigate their ability to control necrotic fungal pathogens such as grey mould. A total of 36 bacteria grown on oxalate minimal (OM) agar plates were tested for oxalate-degrading activity. Five isolates exhibiting the highest oxalate degradation activity were subjected to molecular identification using 16S rRNA gene sequencing. Two isolates exhibiting non-antifungal activity were subjected to disease suppression assays using Arabidopsis-Botrytis systems. The isolate Pseudomonas abietaniphila ODB36, which exhibited significant plant protective ability, was finally selected for further investigation. Based on whole-genome information, the pseudomonad oxalate degrading (podA) gene, which encodes formyl-CoA transferase, was analysed. The podA- mutant did not inhibit Botrytis infection and oxalate toxicity; the defects were recovered by podA complementation. Purified PodA-His converted oxalate to formate and eliminated oxalate toxicity. These results indicate that P. abietaniphila ODB36 and PodA enzyme are associated with various aspects of grey mould disease inhibitory effects.

Aversion center blackening of muskmelon fruit caused by Pseudomonas oryzihabitans, an opportunistic pathogen of humans and warm-blooded animals.

This is the first report of bacterial center blackening in muskmelon fruit caused by Pseudomonas oryzihabitans, which is known as an opportunistic pathogen of humans and warm-blooded animals. The aim of this study was to investigate the microbiological characteristics of this infection. Bacterial center blackening, which can cause aversion in consumers, was observed in muskmelon fruit in South Korea in the fall of 2017. Symptoms included severe black pigmentation in the pulp surrounding the seeds inside muskmelon fruit. Dark brown pigmentation and gram-negative, non-spore-forming, rod-shaped pseudomonads were consistently recovered from the black pigmented pulp tissue of muskmelons. The symptoms after artificial inoculation were the same as those of the natural infection, while the control fruit exhibited no symptoms of infection. Using pathogenicity tests, analytical profile index (API) tests, whole-cell matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and 16S rRNA gene and gyrB region sequencing, the dominant species was identified as P. oryzihabitans. The recent outbreak indicates that P. oryzihabitans poses a potential threat to the global production and transportation of muskmelon as well as food safety.

Simple and economical biosensors for distinguishing Agrobacterium-mediated plant galls from nematode-mediated root knots.

Agrobacterium-mediated plant galls are often misdiagnosed as nematode-mediated knots, even by experts, because the gall symptoms in both conditions are very similar. In the present study, we developed biosensor strains based on agrobacterial opine metabolism that easily and simply diagnoses Agrobacterium-induced root galls. Our biosensor consists of Agrobacterium mannitol (ABM) agar medium, X-gal, and a biosensor. The working principle of the biosensor is that exogenous nopaline produced by plant root galls binds to NocR, resulting in NocR/nopaline complexes that bind to the promoter of the nopaline oxidase gene (nox) operon and activate the transcription of noxB-lacZY, resulting in readily visualized blue pigmentation on ABM agar medium supplemented with X-gal (ABMX-gal). Similarly, exogenous octopine binds to OccR, resulting in OoxR/octopine complexes that bind to the promoter of the octopine oxidase gene (oox) operon and activate the transcription of ooxB-lacZY, resulting in blue pigmentation in the presence of X-gal. Our biosensor is successfully senses opines produced by Agrobacterium-infected plant galls, and can be applied to easily distinguish Agrobacterium crown gall disease from nematode disease.

Barley RNA viromes in six different geographical regions in Korea.

Barley is a kind of cereal grass belonging to the family Poaceae. To examine viruses infecting winter barley in Korea, we carried out a comprehensive study of barley RNA viromes using next-generation sequencing (NGS). A total of 110 barley leaf samples from 17 geographical locations were collected. NGS followed by extensive bioinformatics analyses revealed six different barley viromes: Barley yellow mosaic virus (BaYMV), Barley mild mosaic virus (BaMMV), Barley yellow dwarf virus (BYDV), Hordeum vulgare endornavirus (HvEV), and Barley virus G (BVG). BaYMV and HvEV were identified in all libraries, while other viruses were identified in some specific library. Based on the number of virus-associated reads, BaYMV was a dominant virus infecting winter barley in Korea causing yellow disease symptoms. We obtained nearly complete genomes of six BaYMV isolates and two BaMMV isolates. Phylogenetic analyses indicate that BaYMV and BaMMV were largely grouped based on geographical regions such as Asia and Europe. Single nucleotide polymorphisms analyses suggested that most BaYMV and BaMMV showed strong genetic variations; however, BaYMV isolate Jeonju and BaMMV isolate Gunsan exhibited a few and no SNPs, respectively, suggesting low level of genetic variation. Taken together, this is the first study of barley RNA viromes in Korea.