Cardiac Symptoms During the Russia-Ukraine War: A Google Trends Analysis

Background The 2022 Ukraine-Russian War has led to significant anxiety, anguish, and trauma among the people in Ukraine. The objective of this study was to analyze the Google Trend results of common cardiac symptoms in Ukraine, Russia, and worldwide in 2022 and compare that to 2021 with the hypothesis that common cardiac symptoms in the war-affected regions would be higher compared to the rest of the world. We hypothesize that the search trends of cardiac symptoms would increase in Ukraine given the turmoil caused by the Russian invasion. Methods We queried Google Trends for common cardiac symptoms such as chest pain, dizziness, palpitations, syncope, etc. Google Trends provides results as relative search volume (RSV) displayed in a geographical format. The RSV ranges from 0 to 100, with 0 indicating that the search term is not popular, and 100 indicating the search term's popularity is at its peak. Google Trends of cardiac symptoms in Russia, Ukraine, and worldwide was taken two weeks before and after February 24, 2022, compared with the same period in 2021. To assess the difference in Google Trends between the study periods in 2022 and 2021, the paired t-test was used. Results Overall, Google Trends for cardiac symptoms was lower in Ukraine and Russia than worldwide, in both 2021 and 2022 during the study period. There was a significant reduction in search for chest pain (14 vs. 30.5; p<0.049), pedal edema (40.0 vs 66.6; p approaching 0), and syncope (37.8 vs. 58.4; p<0.002) in Ukraine during the study periods in 2022 compared to 2021. There was a decrease in the searches for dyspnea (44.6 vs. 55.4; p<0.029) in Russia and for dizziness (87.6 vs. 92.8; p<0.005) worldwide. There was an increase in the searches for edema (93.6 vs. 91; p <0.002) and for fatigue (88.6 vs 79.5; p approaching 0) worldwide in study periods in 2022 as compared to 2021. There was no other significant difference between cardiac symptom search trends during the periods evaluated in Ukraine, Russia, and worldwide. Conclusion There appears to be a significant reduction in searching for a few cardiovascular symptoms, namely, chest pain, pedal edema, and syncope in Ukraine, which may be due to a focus on other immediate problems related to war and the availability of the Internet.

Same-Day Discharge after Percutaneous Left Atrial Appendage Closure: Insights from the Nationwide Readmission Database 2015-2019

Data on the feasibility of same-day discharge (SDD) following percutaneous left atrial appendage closure (LAAC) remain limited. We analyzed the US Nationwide Readmission Database from quarter four of 2015 to 2019 to study the safety and feasibility of SDD after LAAC. After excluding non-elective cases and in-hospital deaths, a total of 54,880 cases of LAAC were performed during the study period. Following LAAC, 2% (n=1077) of patients underwent SDD, 88% (n=48,428) underwent next-day discharge (NDD), 5.2% (n=2881) were discharged on the second day (ScD), and 4.5% of patients (n = 2494) were discharged 3 or more days after LAAC. There was no difference in 30-day readmission rates between SDD and NDD (7.3% [n=79] vs 7.4% [n=3585], P=0.94). The hospitalization costs were significantly lower for SDD compared with NDD ($22,963 vs $27,079, P≤0.01). SDD discharge following percutaneous LAAC appears to be safe and is associated with lower hospitalization costs. Further prospective studies are needed to determine the safety and feasibility of SDD with percutaneous LAAC.

Transcatheter valve-in-valve implantation versus redo surgical mitral valve replacement in patients with failed mitral bioprostheses

BACKGROUND

Data on the safety of valve-in-valve transcatheter mitral valve replacement (ViV-TMVR) compared with redo surgical mitral valve replacement (SMVR) in patients with a history of bioprosthetic mitral valve (MV) remain limited.

AIMS

We aimed to evaluate the in-hospital, 30-day and 6-month readmission outcomes of ViV-TMVR compared with redo-SMVR in a real-world cohort.

METHODS

The Nationwide Readmission Database was utilised, analysing data from 2015 to 2019. To determine the adjusted odds ratio (aOR), we used the propensity-matched analysis for major outcomes at index hospitalisation, 30 days, and 6 months during the episode of readmission.

RESULTS

A total of 3,691 patients were included, of these, 24.2% underwent ViV-TMVR and 75.8% underwent redo-SMVR. Patients undergoing ViV-TMVR were older with higher rates of comorbidities. The mean length of stay (15 days vs 4 days) and cost of hospitalisation ($76,558 vs $46,743) were significantly higher for redo-SMVR. The rate of in-hospital all-cause mortality was also significantly lower in ViV-TMVR (2.6% vs 7.3%). By contrast, 30-day all-cause mortality during the episode of readmission (aOR 1.01, 95% confidence interval [CI]: 0.40-2.55) and all-cause readmission rates (aOR 0.82, 95% CI: 0.66-1.02) were similar between both groups. The incidence of all-cause readmissions at 6 months (aOR 0.83, 95% CI: 0.65-1.05) and all-cause mortality during the episode of readmission at 6 months (aOR 1.84, 95% CI: 0.54-6.36) were also comparable. The utilisation of the ViV-TMVR procedure increased significantly during our study duration, from 5.2% to 36.8%, (ptrend<0.01).

CONCLUSIONS

ViV-TMVR is associated with lower odds of in-hospital mortality, complications, and resource utilisation. The all-cause readmissions and 30-day and 6-month mortality during the episode of readmissions were comparable between both groups.

Safety and efficacy of dyslipidemia treatment in NAFLD patients: a meta-analysis of randomized controlled trials

INTRODUCTION AND OBJECTIVES

Practicing physicians often hesitate to use statins and/or other lipid-lowering therapies in NAFLD due to concern for hepatotoxicity. The aim of this study is to examine the safety of lipid lowering therapies in NAFLD patients.

MATERIALS AND METHODS

Data from randomized control trials (RCT) among NAFLD patients were pooled to examine the effect of lipid-lowering therapies on liver chemistry, lipid profile, and liver histology. Results are reported as the mean difference of the change (pretreatment-posttreatment) between the treatment and control group.

RESULTS

A total of 21 placebo-controlled RCT on 1900 patients (304 receiving statins, 520 other lipid-lowering therapies, and 61 combinations) were treated for 26 weeks [Interquartile range (IQR): 17.5-52 weeks]. Pooled data showed an improved lipid profile without any worsening of ALT, AST, total bilirubin, or alkaline phosphatase at the end of the treatment period. NAFLD activity score improved with other lipid-lowering agents but not with statins. There was no change in individual components of NAFLD activity score or fibrosis stage.

CONCLUSION

This meta-analysis of randomized controlled trials examining statins and/or other lipid-lowering therapies in NAFLD patients showed no evidence of worsening liver chemistry. Studies with longer use of lipid-lowering therapies are suggested to examine the benefit of liver histology among patients with NAFLD.

608 Optimising Return to Elective Total Hip Arthroplasty (THA) Following the COVID-19 Pandemic: Lessons Learned and Future Directions

Aim

COVID-19 has led to unprecedented waiting times for elective surgery. Optimising patient pathways is paramount in tackling the backlog. Length of hospital stay (LOS) is an accepted surrogate for successful elective surgery.

The aims of our study were: 1) report on changes in LOS after restarting our elective THA service; 2) identify barriers to early discharge, 3) investigate effectiveness of implemented changes.

Method

A retrospective review of consecutive patients undergoing elective THA, comparing three groups: 1) enhanced care pathway (n=96; 09/2019–12/2019); 2) COVID group (n=56; 03/2021–04/2021); 3) intervention group (n=96; 05/2021–08/2021).

Results

LOS in the enhanced care pathway group was 2.6 ±2.1 days. During initial resumption of elective operating (COVID group) the LOS was 4.8 ±4.5 days (statistically significant increase; p=0.011). Factors affecting LOS included reduced physiotherapy provision; lack of pre-operative occupational therapy review; loss of educational classes and worse pre-operative functional status.

To address these our department employed three new physiotherapists, introduced training for nursing staff and created a post-operative proforma. The LOS subsequently reduced to 3.7 ±4.6days (p=0.166).

Subgroup analysis of the intervention group showed age <75 (p<0.001) and ASA1–2 (p=0.036) were associated with reduced LOS (2.1±1.5 days). Other variables analysed did not significantly affect LOS.

Conclusions

COVID-19 has had a significant effect on LOS, which is still not reversed. For effective resumption of THA services, pre-pandemic enhanced care pathways should be reinstated. With current restrictions preventing face-to-face classes, online educational sessions could be offered. Those younger than 75 years and ASA1–2 are most likely to be discharged without delay.

Components of interprofessional education programs in neonatal medicine: A focused BEME review: BEME Guide No. 73

BACKGROUND

Care delivery in neonatology is dependent on an interprofessional team. Collaborative learning and education amongst professionals can lead to successful management of critically ill patients. This focused BEME review synthesized the components, outcomes, and impact of such interprofessional education (IPE) programs in neonatal medicine.

METHODS

The authors systematically searched four online databases and hand-searched MedEdPublish up to 10 September 2020. Two authors independently screened titles, abstracts, full-texts, performed data extraction and risk of bias assessment related to study methodology and reporting. Discrepancies were resolved by a third author. We reported our findings based on BEME guidance and the STORIES (STructured apprOach to the Reporting in health education of Evidence Synthesis) statement.

RESULTS

We included 17 studies on IPE in neonatal medicine. Most studies were from North America with varying learners, objectives, instruction, and observed outcomes. Learners represented nurses, respiratory therapists, neonatal nurse practitioners, patient care technicians, parents, early interventionists, physicians, and medical trainees amongst others. Risk of bias assessment in reporting revealed poor reporting of resources and instructor training. Bias assessment for study methodology noted moderate quality evidence with validity evidence as the weakest domain. IPE instruction strategies included simulation with debriefing, didactics, and online instruction. Most studies reported level 1 Kirkpatrick outcomes (76%) and few reported level 3 or 4 outcomes (23%). Challenges include buy-in from leadership and the negative influence of hierarchy amongst learners.

CONCLUSIONS

This review highlights IPE program components within neonatal medicine and exemplary practices including a multimodal instructional approach, asynchronous instruction, an emphasis on teamwork, and elimination of hierarchy amongst learners. We identified a lack of reporting on program development and instructor training. Future work should address long term knowledge and skill retention and impact on patient outcomes and organizations.

Auto-immune thyroiditis in SARS-CoV-2 exposed twins

OBJECTIVE

In the coronavirus disease 2019 (COVID-19) pandemic, a spectrum of sequelae affecting different organs has been reported. Of these, the ones affecting the thyroid gland have been reported, especially in the adults.

CASE REPORT

We present previously healthy twin adolescents with no history of thyroid disease, presenting with signs and symptoms of hypothyroidism after recovery from mild COVID-19 infection. Their investigations were consistent with auto-immune thyroiditis with primary hypothyroidism, showing markedly elevated thyroid-stimulating hormone (TSH), suppressed FT4 levels, positive anti-thyroid peroxidase antibody and anti-thyroglobulin antibody titres. They were treated accordingly and showed quick clinical improvement in symptoms.

CONCLUSIONS

This case report demonstrates that COVID-19 infection can be temporally associated with primary hypothyroidism in genetically predisposed children adding more to the growing list of sequelae especially in children.

Trends, Predictors, and Outcomes of Cardiovascular Complications Associated With Polycystic Ovary Syndrome During Delivery Hospitalizations: A National Inpatient Sample Analysis (2002-2019)

Background

Women with polycystic ovary syndrome (PCOS) have an increased risk of pregnancy‐associated complications. However, data on peripartum cardiovascular complications remain limited. Hence, we investigated trends, outcomes, and predictors of cardiovascular complications associated with PCOS diagnosis during delivery hospitalizations in the United States.

Methods and Results

We used data from the National Inpatient Sample (2002–2019). International Classification of Diseases, Ninth Revision (ICD‐9), or International Classification of Diseases, Tenth Revision (ICD‐10), codes were used to identify delivery hospitalizations and PCOS diagnosis. A total of 71 436 308 weighted hospitalizations for deliveries were identified, of which 0.3% were among women with PCOS (n=195 675). The prevalence of PCOS, and obesity among those with PCOS, increased during the study period. Women with PCOS were older (median, 31 versus 28 years; P<0.01) and had a higher prevalence of diabetes, obesity, and dyslipidemia. After adjustment for age, race and ethnicity, comorbidities, insurance, and income, PCOS remained an independent predictor of cardiovascular complications, including preeclampsia (adjusted odds ratio [OR], 1.56 [95% CI, 1.54–1.59]; P<0.01), eclampsia (adjusted OR, 1.58 [95% CI, 1.54–1.59]; P<0.01), peripartum cardiomyopathy (adjusted OR, 1.79 [95% CI, 1.49–2.13]; P<0.01), and heart failure (adjusted OR, 1.76 [95% CI, 1.27–2.45]; P<0.01), compared with no PCOS. Moreover, delivery hospitalizations among women with PCOS were associated with increased length (3 versus 2 days; P<0.01) and cost of hospitalization ($4901 versus $3616; P<0.01).

Conclusions

Women with PCOS had a higher risk of preeclampsia/eclampsia, peripartum cardiomyopathy, and heart failure during delivery hospitalizations. Moreover, delivery hospitalizations among women with PCOS diagnosis were associated with increased length and cost of hospitalization. This signifies the importance of prepregnancy consultation and optimization for cardiometabolic health to improve maternal and neonatal outcomes.

424 Improving Interprofessional Teamwork in Plastic Surgery: A Novel Approach to Microsurgical Skills Training for Theatre Nurses

Aim

Shared mental models between surgeons and scrub nurses allow them to effectively communicate with each other and react efficiently to intraoperative complications. Microsurgery poses unique challenges including the use of an operating microscope, fine instruments, and restricted views of the operative field. Our aim was to design and deliver a microsurgical skills session for theatre nurses and evaluate whether attendance influenced perceived understanding of microsurgery and ability in day-to-day role.

Method

A microsurgical training day for theatre nurses was delivered. This consisted of an introduction to and positioning of the operating microscope and three practical stations involving increasingly complex motor tasks, designed to highlight the importance of instrument handling and improve awareness of microsurgical challenges. Consultant plastic surgeons acted as scrub nurses to add an element of role-reversal. Qualitative and quantitative feedback was collected.

Results

Eight theatre nurses participated, all responded ‘strongly agree’ or ‘agree’ that the training was enjoyable, improved their understanding of microsurgery and was relevant and helpful to their day-to-day role. All attendees strongly agreed that they would partake in similar sessions in the future.

Conclusions

Role-reversal and skills-based training is a valuable tool in improving multidisciplinary collaboration in microsurgery. Increasing shared knowledge of complex procedures prospers effective teamwork and communication, which leads to improved efficiency and better patient care. Our study is a first step towards development of a standardized microsurgical skills course for theatre nurses and has broader implications for interprofessional education across all surgical specialties.

Identifying predictors of ventral hernia recurrence: systematic review and meta-analysis

BACKGROUND

Ventra hernias are increasing in prevalence and many recur despite attempted repair. To date, much of the literature is underpowered and divergent. As a result there is limited high quality evidence to inform surgeons succinctly which perioperative variables influence postoperative recurrence. This systematic review aimed to identify predictors of ventral hernia recurrence.

METHODS

PubMed was searched for studies reporting prognostic data of ventral hernia recurrence between 1 January 1995 and 1 January 2018. Extracted data described hernia type (primary/incisional), definitions of recurrence, methods used to detect recurrence, duration of follow-up, and co-morbidity. Data were extracted for all potential predictors, estimates and thresholds described. Random-effects meta-analysis was used. Bias was assessed with a modified PROBAST (Prediction model Risk Of Bias ASsessment Tool).

RESULTS

Screening of 18 214 abstracts yielded 274 individual studies for inclusion. Hernia recurrence was defined in 66 studies (24.1 per cent), using 41 different unstandardized definitions. Three patient variables (female sex, age 65 years or less, and BMI greater than 25, 30, 35 or 40 kg/m2), five patient co-morbidities (smoking, diabetes, chronic obstructive pulmonary disease, ASA grade III-IV, steroid use), two hernia-related variables (incisional/primary, recurrent/primary), six intraoperative variables (biological mesh, bridged repair, open versus laparoscopic surgery, suture versus mesh repair, onlay/retrorectus, intraperitoneal/retrorectus), and six postoperative variables (any complication, surgical-site occurrence, wound infection, seroma, haematoma, wound dehiscence) were identified as significant prognostic factors for hernia recurrence.

CONCLUSION

This study summarized the current evidence base for predicting ventral hernia recurrence. Results should inform best practice and future research.

In vitro translation of the full-length RNA transcript of figwort mosaic virus (Caulimovirus)

The circular DNA genome of FMV consists of seven tandemly arranged genes placed successively on a full-length RNA transcript that spans the entire circular viral genome. This transcript is a tentative mRNA for at least five of the six major conserved genes of this virus (genes I-V) that are positioned on this transcript. The sixth major gene (gene VI) is expressed as a separate monocistronic transcript. A long 5'-nontranslated leader (598 nucleotides), a small nonconserved gene (VII), and a short intergenic region (57 nucleotides) precede the five major conserved genes (I through V) on the full-length transcript. A reporter gene (CAT), as a separate cistron or fused in-frame, to viral cistrons in various downstream positions in cloned versions of the viral genome was used in a transcription vector to generate artificial full-length transcripts of FMV. When these mRNAs were translated in vitro (rabbit reticulocyte lysate system), the reporter gene was translated efficiently in all positions. Translation of internal native viral gene positioned on the full-length transcript of FMV was also determined (the gene VI product). These observations suggest that the full-length FMV transcript functions as a polycistronic mRNA in plants. Results are best explained on the basis of translational coupling/relay race model.

Sequence variation in two genes determines the efficacy of transmission of citrus tristeza virus by the brown citrus aphid

Vector transmission is an important part of the viral infection cycle, yet for many viruses little is known about this process, or how viral sequence variation affects transmission efficacy. Here we examined the effect of substituting genes from the highly transmissible FS577 isolate of citrus tristeza virus (CTV) in to the poorly transmissible T36-based infectious clone. We found that introducing p65 or p61 sequences from FS577 significantly increased transmission efficacy. Interestingly, replacement of both genes produced a greater increase than either gene alone, suggesting that CTV transmission requires the concerted action of co-evolved p65 and p61 proteins.

Citrus tristeza virus-host interactions

Citrus tristeza virus (CTV) is a phloem-limited virus whose natural host range is restricted to citrus and related species. Although the virus has killed millions of trees, almost destroying whole industries, and continually limits production in many citrus growing areas, most isolates are mild or symptomless in most of their host range. There is little understanding of how the virus causes severe disease in some citrus and none in others. Movement and distribution of CTV differs considerably from that of well-studied viruses of herbaceous plants where movement occurs largely through adjacent cells. In contrast, CTV systemically infects plants mainly by long-distance movement with only limited cell-to-cell movement. The virus is transported through sieve elements and occasionally enters an adjacent companion or phloem parenchyma cell where virus replication occurs. In some plants this is followed by cell-to-cell movement into only a small cluster of adjacent cells, while in others there is no cell-to-cell movement. Different proportions of cells adjacent to sieve elements become infected in different plant species. This appears to be related to how well viral gene products interact with specific hosts. CTV has three genes (p33, p18, and p13) that are not necessary for infection of most of its hosts, but are needed in different combinations for infection of certain citrus species. These genes apparently were acquired by the virus to extend its host range. Some specific viral gene products have been implicated in symptom induction. Remarkably, the deletion of these genes from the virus genome can induce large increases in stem pitting (SP) symptoms. The p23 gene, which is a suppressor of RNA silencing and a regulator of viral RNA synthesis, has been shown to be the cause of seedling yellows (SY) symptoms in sour orange. Most isolates of CTV in nature are populations of different strains of CTV. The next frontier of CTV biology is the understanding how the virus variants in those mixtures interact with each other and cause diseases.

Li-O2 Kinetic Overpotentials: Tafel Plots from Experiment and First-Principles Theory

We report the current dependence of the fundamental kinetic overpotentials for Li-O2 discharge and charge (Tafel plots) that define the optimal cycle efficiency in a Li-air battery. Comparison of the unusual experimental Tafel plots obtained in a bulk electrolysis cell with those obtained by first-principles theory is semiquantitative. The kinetic overpotentials for any practical current density are very small, considerably less than polarization losses due to iR drops from the cell impedance in Li-O2 batteries. If only the kinetic overpotentials were present, then a discharge-charge voltaic cycle efficiency of ∼85% should be possible at ∼10 mA/cm(2) superficial current density in a battery of ∼0.1 m(2) total cathode area. We therefore suggest that minimizing the cell impedance is a more important problem than minimizing the kinetic overpotentials to develop higher current Li-air batteries.

A hospital based study of prevalence of gestational diabetes mellitus in an urban population of India

OBJECTIVE

A cross-sectional institutional-based study was undertaken to know the prevalence of Gestational Diabetes Mellitus (GDM) among Indian pregnant women.

SUBJECTS AND METHODS

325 pregnant women were screened for evidence of diabetes who were previously not known to be diabetic. They underwent 75 g, 2 hour, oral glucose tolerance test (OGTT). Chi-square test was done for statistically association of variables in GDM.

RESULTS AND CONCLUSIONS

The results of this study indicate that bad obstetrics history, obese patient on high calorie diet especially non vegetarian diet with less physical activity are highly prone to develop GDM.

Partial trisomy 10p12.33 and partial monosomy 13q32.1: case report and a literature review

We report on a preterm neonate with a deletion of the distal long arm of chromosome 13q32.1 and partial trisomy of the short arm of chromosome 10p12.33. The patient has intrauterine growth retardation, microphthalmia, macrocephaly, holoprosencephaly, patent ductus arteriosus, aortic isthmus hypoplasia, right renal agenesis, imperforate anus, ambiguous genitalia, pleural effusion and vertebral anomaly. Analysis using an oligonucleotide microarray (U-array Cyto6000 array platform (Human Genome build: hg 18) indicated that there was a partial trisomy of chromosome 10(19.5 Mb gain) involving 298 oligonucleotides from 10pter to 10p12.33, and a partial monosomy of chromosome 13(18.3 Mb deleted) involving 313 oligonucleotides from 13q32.1 to 13qter. This is the first report of a patient with partial trisomy 10p12.33 and partial monosomy 13q32.1.

High origin of ulnar artery in South Indian male cadaver: a case report

Superficial ulnar artery, a rare variation may arise from axillary or brachial artery. Here we report a case of high origin of superficial ulnar artery from the axillary artery. Superficial ulnar artery, after running under the bicipital aponeurosis in the cubital fossa, it terminated as superficial palmar arch in the hand. We also discuss its clinical and embryological relevance.

Characterization of the cis-acting elements controlling subgenomic mRNAs of citrus tristeza virus: production of positive- and negative-stranded 3'-terminal and positive-stranded 5'-terminal RNAs

Citrus tristeza virus (CTV), a member of the Closteroviridae, has an approximately 20-kb positive-sense RNA genome with two 5' ORFs translated from the genomic RNA and 10 3' genes expressed via nine or ten 3'-terminal subgenomic (sg) RNAs. The expression of the 3' genes appears to have properties intermediate between the smaller viruses of the "alphavirus supergroup" and the larger viruses of the Coronaviridae. The sgRNAs are contiguous with the genome, without a common 5' leader, and are associated with large amounts of complementary sgRNAs. Production of the different sgRNAs is regulated temporally and quantitatively, with the highly expressed genes having noncoding regions (NCR) 5' of the ORFs. The cis-acting elements that control the highly expressed major coat protein (CP) gene and the intermediately expressed minor coat protein (CPm) gene were mapped and compared. Mutational analysis showed that the CP sgRNA controller element mapped within nts -47 to -5 upstream of the transcription start site, entirely within the NCR, while the CPm control region mapped within a 57 nt sequence within the upstream ORF. Although both regions were predicted to fold into two stem-loop structures, mutagenesis suggested that primary structure might be more important than the secondary structure. Because each controller element produced large amounts of 3'-terminal positive- and negative-stranded sgRNAs, we could not differentiate whether the cis-acting element functioned as a promoter or terminator, or both. Reversal of the control element unexpectedly produced large amounts of a negative-stranded sgRNA apparently by termination of negative-stranded genomic RNA synthesis. Further examination of controller elements in their native orientation showed normal production of abundant amounts of positive-stranded sgRNAs extending to near the 5'-terminus, corresponding to termination at each controller element. Thus, each controller element produced three sgRNAs, a 5'-terminal positive strand and both positive- and negative-stranded 3'-terminal RNAs. Therefore, theoretically CTV could produce 30-33 species of RNAs in infected cells.

5'-coterminal subgenomic RNAs in citrus tristeza virus-infected cells

Three unusual 5' coterminal positive-stranded subgenomic (sg) RNAs, two of about 0.8 kb and one of 10 kb (designated LMT1, LMT2, and LaMT, respectively), from Citrus spp. plants and Nicotiana benthamiana protoplasts infected with Citrus tristeza virus (CTV) were characterized. The 5' termini of the LMT RNAs were mapped by runoff reverse transcription and found to correspond with the 5' terminus of the genomic RNA. The LMT 5'-coterminal sgRNAs consisted of two modal lengths of 744--746 and 842--854 nts. The 3' of the LaMT RNAs terminated near the junction of ORF 1b and ORF 2 (p33). None of the 5' sgRNAs had detectable amounts of corresponding negative-sense RNAs, as occurs with the genomic and 3' coterminal subgenomic RNAs of CTV. The abundance of the short and long 5' sgRNAs differed considerably in infected cells. The LMT RNAs were considerably more abundant than the genomic RNAs, while the larger LaMT RNA accumulated to much lower levels. The kinetics of accumulation of LMT1 and LMT2 in synchronously infected protoplasts differed. The larger RNA, LMT1, accumulated earlier with a strong hybridization signal at 2 days postinfection, a time when only traces of genomic and 3' sgRNAs were detected. The lack of corresponding RNAs, that could be 3' cleavage products corresponding to the 5' coterminal sgRNAs and the lack of complementary negative strands, suggest that these sgRNAs were produced by termination during the synthesis of the genomic positive strands.

Amplification of Citrus tristeza virus from a cDNA clone and infection of citrus trees

Isolates of the Closterovirus, Citrus tristeza virus (CTV), are populations of disparate genotypes and defective RNAs developed during long periods of vegetative propagation of citrus trees. Because it has not been possible to obtain pure cultures of the virus, it is not known what components of the population are primarily responsible for induction of diseases. We previously developed an infectious cDNA clone from which in vitro-produced RNA transcripts could infect protoplasts (Satyanarayana et al., 1999, Proc. Natl. Acad. Sci. USA 96, 7433-7438). However, neither the RNA transcripts nor virions from transcript-infected protoplasts were competent for infection of citrus trees. Using a green fluorescent protein-marked virus as inoculum, we found that the approximately 20-kb RNA from virions or transcripts of cDNA infected only a small percentage of protoplasts ( approximately 0.01%), but virions could infect more than 80% of the protoplasts. Based on this information, we amplified the virus from the cDNA clone (recombinant virus) by successive passages in protoplasts using virions in crude sap as inoculum. By the third to seventh passages in protoplasts, maximal amounts of recombinant progeny virus were produced, which were used for inoculation of small citrus trees by slashing stems in the presence of virion preparations. A relatively high percentage of plants became infected with the recombinant virus from protoplasts, resulting in the first defined pure culture of CTV in plants. The comparative biology of the pure culture of recombinant CTV with that of the parental population in planta demonstrated that the recombinant virus retained through all of the recombinant DNA manipulations the normal functions of replication, movement, and aphid transmissibility, and had a symptom phenotype indistinguishable from that of the parental population. Additionally, fulfilling Koch's postulates of the first pure culture of CTV in plants suggested that the major genotype of the CTV T36 population is the primary determinant of the symptom phenotype. We could distinguish no biological contributions resulting from the minor genotypes and defective RNAs of the parental population.

Nucleotide sequence of L1 and part of P1 of hexon gene of fowl adenovirus associated with hydropericardium hepatitis syndrome differs with the corresponding region of other fowl adenoviruses

In order to study the serotypic variations in hydropericardium hepatitis syndrome (HHS) causing virus, the DNA was extracted from the purified virus, a 0.7 kb variable region of hexon gene encoding L1 and part of P1 amplified and sequenced. Both nucleotide and derived amino acid sequences, corresponding to the variable region, were compared with the published fowl adenovirus sequences (FAV serotypes 10, 1 and 8). As expected the 0.7 kb sequence showed single open reading frame (ORF). There was a nucleotide sequence variation of 8.2, 28.1 and 40.3%, respectively, with FAV serotypes 10, 1 and 8. The dendrogram constructed with the nucleotide sequences showed that HHS virus and FAV10 are closer to each other and are away to FAV1 and FAV8. However, the derived amino acid sequence showed variations as high as 28.8, 38 and 45.1% with FAV serotypes 10, 1 and 8, respectively. Such high degree variation has been found due to the shift in the reading frame caused by deletions indicating that the FAV4 associated with HHS is unique and different from FAV10. To the best of our knowledge this is the first report on nucleotide sequence analysis of hexon gene fragment of FAV4 associated with HHS.

Closterovirus encoded HSP70 homolog and p61 in addition to both coat proteins function in efficient virion assembly

Assembly of the viral genome into virions is a critical process of the virus life cycle often defining the ability of the virus to move within the plant and to be transmitted horizontally to other plants. Closteroviridae virions are polar helical rods assembled primarily by a major coat protein, but with a related minor coat protein at one end. The Closteroviridae is the only virus family that encodes a protein with similarity to cellular chaperones, a 70-kDa heat-shock protein homolog (HSP70h). We examined the involvement of gene products of Citrus tristeza virus (CTV) in virion formation and found that the chaperone-like protein plus the p61 and both coat proteins were required for efficient virion assembly. Competency of virion assembly of different CTV mutants was assayed by their ability to be serially passaged in Nicotiana benthamiana protoplasts using crude sap as inoculum, and complete and partial virus particles were analyzed by serologically specific electron microscopy. Deletion mutagenesis revealed that p33, p6, p18, p13, p20, and p23 genes were not needed for virion formation. However, deletion of either minor- or major-coat protein resulted in formation of short particles which failed to be serially transferred in protoplasts, suggesting that both coat proteins are required for efficient virion assembly. Deletion or mutation of HSP70h and/or p61 dramatically reduced passage and formation of full-length virions. Frameshift mutations suggested that the HSP70h and p61 proteins, not the RNA sequences, were needed for virion assembly. Substitution of the key amino acid residues in the ATPase domain of HSP70h, Asp(7) to Lys or Glu(180) to Arg, reduced assembly, suggesting that the chaperone-like ATPase activity is involved in assembly. Both HSP70h and p61 proteins appeared to contribute equally to assembly, consistent with coordinate functions of these proteins in closterovirus virion formation. The requirement of two accessory proteins in addition to both coat proteins for efficient assembly is uniquely complex for helical virions.

The fitness of citrus tristeza virus defective RNAs is affected by the lengths of their 5'- and 3'-termini and by the coding capacity

Populations of the Closterovirus Citrus tristeza virus (CTV) generally contain defective RNAs (dRNAs) that vary in size, abundance, and sequence. The variation in abundance of the different dRNAs in a population suggests selection for those of higher fitness. To examine factors affecting fitness of dRNAs, we investigated a series of in vitro constructed dRNAs for their ability to be amplified in protoplasts by an efficiently replicated CTV deletion mutant. The minimal sequences required for accumulation of the dRNAs were within the genomic 5' proximal approximately 1 kb and the 3' 270 nucleotides. However, other factors were involved, because a dRNA with only the minimal sequences failed to be replicated. Rescue of a nonviable dRNA by insertion of nonviral sequences between the termini suggested that "spacing" between terminal cis-acting signals influenced fitness. A continuous open reading frame (ORF) through most of the sequences derived from the 5' of the genome was a requirement for dRNA amplification. In general, insertions, deletions, or nucleotide substitutions were tolerated in the dRNAs as long as an ORF was retained, whereas dRNAs with mutations that prematurely terminated the ORF were not viable. To discriminate between a requirement for an essential protein and ribosomal travel, perhaps to present replication signals to the replicase complex, mutations were made to modify the potential protein but still maintain an ORF. Deletions, insertions of nonviral sequences, or switching of reading frames that altered the amino acid sequence of the protein, except the N-terminal 161 amino acids, did not destroy the fitness of the dRNAs. Yet termination of the ORF in the middle of nonviral sequences did destroy the ability of the dRNAs to be amplified. These results suggest that even though a continuous ORF was needed for fitness, its protein product did not affect the amplification of the dRNAs.

The p20 gene product of Citrus tristeza virus accumulates in the amorphous inclusion bodies

Citrus tristeza virus (CTV) has 10 3' open reading frames (ORFs) of unknown function except for the two coat proteins. The highest produced subgenomic RNAs are those of the major coat protein gene (p25) and the 3' most genes, p20 and p23. The proteins from three ORFs, p25, p27, and p20, were examined in the yeast two-hybrid assay for the interactions between themselves and to one another. The p20 protein exhibited a high affinity for itself, suggesting that it might aggregate in infected cells. The cytopathology of CTV infections includes characteristic paracrystalline and amorphous inclusions in the phloem elements of infected citrus. Polyclonal antiserum raised against the bacterial expressed p20 gene product detected a protein of approximately 22-23 kDa, which accumulated to relatively high levels in CTV-infected citrus, but not in healthy citrus. Immunogold localization using antibodies to p20 protein showed strong and specific labeling of the amorphous inclusion bodies present in CTV-infected cells. Mesophyll protoplasts of Nicotiana benthamiana transfected with a CTV mutant containing the green fluorescent protein (GFP) ORF fused in-frame to the 3' end of p20 protein ORF expressed high levels of GFP. The fusion protein was concentrated in one specific area in the cytoplasm and lacked an organized shape. Accumulation of high levels of p20 protein in infected tissue, specific localization of the p20-GFP fusion protein, immunolocalization of p20 protein into amorphous inclusions, and strong homologous p20 protein-p20 protein interactions in the yeast-two-hybrid assay suggest that the p20 protein of CTV is a major component of the amorphous inclusion bodies present in CTV-infected cells.

Sequences of Citrus tristeza virus separated in time and space are essentially identical

The first Citrus tristeza virus (CTV) genomes completely sequenced (19.3-kb positive-sense RNA), from four biologically distinct isolates, are unexpectedly divergent in nucleotide sequence (up to 60% divergence). Understanding of whether these large sequence differences resulted from recent evolution is important for the design of disease management strategies, particularly the use of genetically engineered mild (essentially symptomless)-strain cross protection and RNA-mediated transgenic resistance. The complete sequence of a mild isolate (T30) which has been endemic in Florida for about a century was found to be nearly identical to the genomic sequence of a mild isolate (T385) from Spain. Moreover, samples of sequences of other isolates from distinct geographic locations, maintained in different citrus hosts and also separated in time (B252 from Taiwan, B272 from Colombia, and B354 from California), were nearly identical to the T30 sequence. The sequence differences between these isolates were within or near the range of variability of the T30 population. A possible explanation for these results is that the parents of isolates T30, T385, B252, B272, and B354 have a common origin, probably Asia, and have changed little since they were dispersed throughout the world by the movement of citrus. Considering that the nucleotide divergence among the other known CTV genomes is much greater than those expected for strains of the same virus, the remarkable similarity of these five isolates indicates a high degree of evolutionary stasis in some CTV populations.

The 23-kDa protein coded by the 3'-terminal gene of citrus tristeza virus is an RNA-binding protein

The 23-kDa protein (p23), encoded by the 3'-proximal gene of the RNA of Citrus tristeza virus (CTV), was overexpressed in Escherichia coli fused to the maltose-binding protein and purified by affinity chromatography. Gel retardation and UV crosslinking assays demonstrated that p23 has the ability to cooperatively bind single-stranded RNA in a non-sequence-specific manner. Formation of the p23-RNA complex was dependent on the conformational state of p23 and on the presence of a basic region, but the complex was stable at high salt concentrations, suggesting that interactions other than those between the negatively charged RNA and the basic region of p23 are involved. Competition assays showed that the affinity of p23 for single-stranded and double-stranded RNA was similar but considerably higher than for single-stranded and double-stranded DNA. By use of a series of artificially generated mutants, the RNA-binding domain of p23 was mapped between positions 50-86, a region containing several basic amino acids and a putative zinc-finger domain. Additional p23-derivatives lacking the conserved residues presumably involved in coordinating the zinc ion showed RNA-binding activity, but with an apparent dissociation constant higher than the wild-type protein. These conserved residues might confer binding specificity or increase binding stability in vivo. Within the Closteroviridae family, p23 is the only protein characterized so far showing RNA-binding activity.

Replication of heterologous combinations of helper and defective RNA of citrus tristeza virus

Citrus tristeza virus (CTV) populations are among the more complex of plant RNA viruses with unusual mixtures of strains and defective RNAs (dRNAs). Citrus plants infected with different CTV isolates contain multiple dRNA molecules that differ in size and relative abundance within and between isolates. Additionally, we found mixtures of heterologous dRNAs in populations. To examine the replication of CTV dRNAs, the protoplast system had to be extended to support helper-assisted amplification of input dRNAs. The use of freshly extracted sap of CTV-infected tissue as inoculum increased the infection of Nicotiana benthamiana protoplasts sufficiently to result in accumulation of high levels of CTV RNAs as well as dRNAs within 2 or 3 days postinoculation. A series of dRNA-like molecules, each with a single large internal deletion, were created from an infectious cDNA clone of the CTV T36 isolate and examined for amplification in N. benthamiana protoplasts using a CTV deletion mutant as the helper virus. Of 12 synthetic dRNAs, only three with sizes of 3650, 3819, and 4460 nucleotides were efficiently replicated. CTV dRNA replication did not appreciably affect levels of accumulation of the genomic or the subgenomic RNAs of the helper virus. To investigate the maintenance of dRNAs in CTV populations, we examined heterologous interactions between dRNAs and helper viruses. Wild-type populations of heterologous strains T68 and T3, as well as the homologous T36, supported replication of synthetic T36 dRNAs. Replacement in the T36 dRNA of the 5' region, which is most variable among CTV strains, with the corresponding sequences from VT, T68, T3, or T30 resulted in chimeric dRNAs that failed to be replicated by the T36 helpers but were replicated to detectable levels by the T68 helper. The differential specificities of different CTV replicase complexes with dRNA replication signals is one possible factor that affects the maintenance of dRNA population structures.

An engineered closterovirus RNA replicon and analysis of heterologous terminal sequences for replication

Citrus tristeza virus (CTV) populations in citrus trees are unusually complex mixtures of viral genotypes and defective RNAs developed during the long-term vegetative propagation of the virus and by additional mixing by aphid transmission. The viral replication process allows the maintenance of minor amounts of disparate genotypes and defective RNAs in these populations. CTV is a member of the Closteroviridae possessing a positive-stranded RNA genome of approximately 20 kilobases that expresses the replicase-associated genes as an approximately 400-kDa polyprotein and the remaining 10 3' genes through subgenomic mRNAs. A full-length cDNA clone of CTV was generated from which RNA transcripts capable of replication in protoplasts were derived. The large size of cDNA hampered its use as a genetic system. Deletion of 10 3' genes resulted in an efficient RNA replicon that was easy to manipulate. To investigate the origin and maintenance of the genotypes in CTV populations, we tested the CTV replicase for its acceptance of divergent sequences by creating chimeric replicons with heterologous termini and examining their ability to replicate. Exchange of the similar 3' termini resulted in efficient replication whereas substitution of the divergent (up to 58% difference in sequence) 5' termini resulted in reduced but significant replication, generally in proportion to the extent of sequence divergence.

Treatment of age-related cognitive decline with a herbal formulation : a double-blind study

There is little published research in mainstream Indian journals of the clinical psychotropic properties of herbal medicines. The present study therefore evaluated the psychotropic effects of Memorin (from a pharmaceutical house based at Maharashtra), a herbal formulation. Subjects with DSM-IV age-related cognitive decline were randomized to receive Memorin (n=22) or placebo (n=23) for three months. Before and after treatment, all subjects completed a battery of neuropsychological tests that assessed visual and verbal memory, visuospatial skills, and perceptuomotor functioning Subjects and rater were alike blind to treatment group. The results revealed that in the Memorin group, on most tests significant improvement in performances were observed after treatment; improvement in many of the memory tasks was however confined to males; age did not significantly influence the results. In contrast, in placebo-treated subjects there was little therapeutic gain. It is concluded that irrespective of the subject's actual age, Memorin may benefit elderly persons, particularly males, who experience age-related cognitive decline.

Evidence that whitefly-transmitted cowpea mild mottle virus belongs to the genus Carlavirus

Two strains of whitefly-transmitted cowpea mild mottle virus (CPMMV) causing severe (CPMMV-S) and mild (CPMMV-M) disease symptoms in peanuts were collected from two distinct agro-ecological zones in India. The host-range of these strains was restricted to Leguminosae and Chenopodiaceae, and each could be distinguished on the basis of symptoms incited in different hosts. The 3'-terminal 2500 nucleotide sequence of the genomic RNA of both the strains was 70% identical and contains five open reading frames (ORFs). The first three (P25, P12 and P7) overlap to form a triple gene block of proteins, P32 encodes the coat protein, followed by P12 protein located at the 3' end of the genome. Genome organization and pair-wise comparisons of amino acid sequences of proteins encoded by these ORFs with corresponding proteins of known carlaviruses and potexviruses suggest that CPMMV-S and CPMMV-M are closely related to viruses in the genus Carlavirus. Based on the data, it is concluded that CPMMV is a distinct species in the genus Carlavirus.

Peanut yellow spot virus is a member of a new serogroup of Tospovirus genus based on small (S) RNA sequence and organization

Peanut yellow spot virus (PYSV) represents a distinct tospovirus species based on serology and nucleic acid hybridization. THe sequence of the S RNA was 2970 nucleotides with 22 nucleotide long inverted repeats (with three mismatches) at the termini. The coding was ambisense with a long open reading frame (ORF) in each strand. The 5'-large ORF (1,400 nucleotides in the viral sense (v) strand) encoded a protein with a predicted size of 53.2 kDa that was identified as the nonstructural (NSs) protein based on 16-21% sequence identity and 42-48% sequence similarity with other tospoviruses. A 3' ORF (741 nucleotides) in the virus complementary (vc) sense encoded a 28.0 kDa protein that was identified as the nucleocapsid (N) gene based on immuno-blot analysis of the in vitro expressed protein with PYSV polyclonal antiserum. The predicted N protein had 24-28% amino acid sequence identity and 44-51% sequence similarity with the members of other serogroups. In contrast to other tospoviruses, a third ORF (204 nucleotides) occurred in the vc strand, which could encode a protein with a predicted size of 7.5 kDa with two strong hydrophobic regions. The low degree of homology of N and NSs protein sequences with other serogroup members coupled with an additional ORF suggests that PYSV should be classified as a distinct species of the Tospovirus genus. This conclusion also is supported by the absence of serological cross reaction with other serogroups, and biological characteristics including thrips transmission, symptoms and host range.