Summary Huanglongbing (HLB) is the most devastating citrus disease in the world. Almost all commercial citrus varieties are susceptible to the causal bacterium, Candidatus Liberibacter asiaticus (CLas), which is transmitted by the Asian citrus psyllid (ACP). Currently, there are no effective management strategies to control HLB. HLB‐tolerant traits have been reported in some citrus relatives and citrus hybrids, which offer a direct pathway for discovering natural defence regulators to combat HLB. Through comparative analysis of small RNA profiles and target gene expression between an HLB‐tolerant citrus hybrid (Poncirus trifoliata × Citrus reticulata) and a susceptible citrus variety, we identified a panel of candidate defence regulators for HLB‐tolerance. These regulators display similar expression patterns in another HLB‐tolerant citrus relative, with a distinct genetic and geographic background, the Sydney hybrid (Microcitrus virgata). Because the functional validation of candidate regulators in tree crops is always challenging, we developed a novel rapid functional screening method, using a C. Liberibacter solanacearum (CLso)/potato psyllid/Nicotiana benthamiana interaction system to mimic the natural transmission and infection circuit of the HLB complex. When combined with efficient virus‐induced gene silencing in N. benthamiana, this innovative and cost‐effective screening method allows for rapid identification and functional characterization of regulators involved in plant immune responses against HLB, such as the positive regulator BRCA1‐Associated Protein, and the negative regulator Vascular Associated Death Protein.

Background:The aim of this study was to analyze the predictability of the Kwok and Caton periodontal prognosis system by investigating tooth survival within a 64-month period and to compare this to other well-established prognosis systems. Methods: This retrospective study included the records of patients who had a minimum of two dental exams at least 12 months apart at a single Universityaffiliated Dental Center. Data including patients' age, sex, length of follow-up period, initial tooth prognosis, revised tooth prognosis, tooth type, and number of teeth lost at the latest exam were recorded. Descriptive analysis was used for data interpretation.Results: A total of 4,046 teeth from 174 patients qualified for the study. Teeth with initial poorer prognosis had a higher chance of being extracted compared with those with a better initial prognosis. Tooth survival rate at the latest followup for those with an initial favorable, questionable, unfavorable, and hopeless prognosis was 97.9%, 90.7%, 62.5%, and 17.7%, respectively. Teeth initially assigned to a poorer prognosis category had a higher proportion that changed to a worse prognosis at the latest periodontal exam. Conclusions:The Kwok and Caton prognosis system can predictably determine tooth survivability within a 5-year period. The defined categories of this prognosis system are more reliable than that of other systems in the short-term. However, long-term (>5 years) prediction accuracy of this prognosis system needs further investigation.

Purpose: We describe two case studies that use embodiment in virtual reality as a treatment for chronic low back pain. The purpose of this case series was to determine the feasibility of a novel virtual reality-based digital therapeutic for the treatment of chronic pain. Patients and Methods: Two patients with chronic low back pain received seven sessions, two sessions per week, of a novel digital therapeutic that combines virtual embodiment with graded motor imagery to deliver functional rehabilitation exercises using an off-the-shelf virtual reality system. Pain intensity was measured using a visual analog scale before and after each session to get an indication whether individual sessions of virtual embodiment training decrease pain intensity. Pain catastrophizing scale was assessed before the first session and after the seventh session to determine the extent to which virtual embodiment training can improve psychological symptoms of chronic low back pain. Results: In both patients, pain intensity was improved after individual sessions of virtual embodiment training as measured by a paired t-test: (Patient A: t = 2.890, P < 0.05) and (Patient B: t = 5.346, P < 0.005). This indicates that individual sessions of virtual embodiment training decrease pain intensity. In both patients, improvements were observed in three subscales of the pain catastrophizing scale (rumination, magnification, and helplessness). This indicates that virtual embodiment training may have benefits for chronic pain symptoms such as pain intensity, pain-related mobility impairment, and disability. Conclusion: This case series provides evidence that embodiment in virtual reality improves symptoms of persistent chronic low back pain. We propose a mechanism by which virtual embodiment may improve chronic pain symptoms by recontextualizing sensory feedback from the body as patients engage in functional rehabilitation exercises while in virtual reality.

BACKGROUND Chronic pain has long been a major health burden that has been addressed through numerous forms of pharmacological and non-pharmacological treatment. One of the tenets of modern medicine is to minimize risk while providing efficacy. Because of its non-invasive nature, Virtual Reality provides an attractive platform for potentially developing novel therapeutic modalities. OBJECTIVE We describe a feasibility study that use embodiment in virtual reality as a treatment for chronic pain. The purpose of this study was to determine the feasibility of a novel virtual reality-based digital therapeutic for the treatment of chronic pain. METHODS An open label study assessed the feasibility of using virtual embodiment in virtual reality to treat chronic pain (Clinicaltrials.gov Identifier: NCT04060875). Twenty-four chronic pain patients were recruited from local pain clinics and completed eight session of a novel digital therapeutic that combines virtual embodiment with graded motor imagery to deliver functional rehabilitation exercises over the course of four weeks. Pain intensity as measured by a visual analog scale before and after each virtual embodiment training session was used as a primary outcome measure. Additionally, a battery of patient reported pain questionnaires (Fear and Avoidance Beliefs Questionnaire, OSWESTRY, Pain Catastrophizing Scale, and Patient Health Questionnaire) were administered before and after eight sessions of virtual embodiment training as exploratory outcome measures to get an indication if the measures are appropriate and warrant a larger randomized controlled trial. RESULTS A two-way ANOVA on session x pre vs. post Virtual embodiment training revealed that individual virtual embodiment training sessions significantly reduced the intensity of pain as measured by visual analog scale. Perceived disability due to lower back pain as measured by OSWESTRY significantly improved over the four-week course of virtual embodiment regimen. Improvement was also observed on the helplessness subscale of the Pain Catastrophizing Scale. CONCLUSIONS This study provide evidence that functional rehabilitation exercises delivered in virtual reality are safe and may have positive effects on alleviating the symptoms of chronic pain. These results support the justification for a larger randomized controlled trial to assess the extent to which virtual embodiment training can exert an effect on symptoms associated with chronic pain. CLINICALTRIAL Clinicaltrials.gov Identifier: NCT04060875