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1.
Indian J Otolaryngol Head Neck Surg ; 76(5): 4554-4558, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39376290

RESUMEN

To determine the association of adenoid hypertrophy with allergic rhinitis in pediatric patients based on Simplified Visual Analog Scale and serum IgE levels. The present study was conducted in our tertiary care centre on 130 patients planned for adenoidectomy from May 2022 to June 2023. Children were divided into two groups based on IgE levels and Allergic history- Group I: who had raised immunoglobulin E levels with allergic rhinitis (according to ARIA guidelines) before adenoidectomy (n = 69) and Group II: who had normal immunoglobulin E levels pre-operatively (n = 72). VAS scoring was done in both groups and compared pre and post operatively. In our study it was found that the adenoid volume was more in patients with allergic history and increased IgE levels as compared to those with normal IgE levels (p < 0.05) pre-operatively. Also, the difference between pre-operative VAS score among Group I and Group II was statistically significant (p = 0.046). Also, the difference between postoperative VAS score among Group I and group II was also statistically significant (p = 0.043). There was statistically significant higher change in VAS score in Group II post-operatively (p = 0.027). sOur study demonstrates that children with allergic rhinitis tend to present earlier with symptoms of adenoid hypertrophy. In addition, children without allergic history show better post-operative VAS scores as the allergic component still prevails in children with allergic history.

2.
Arch Virol ; 169(10): 194, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39249561

RESUMEN

A novel grapevine viroid was discovered in an asymptomatic grapevine of Indian rootstocks. The whole genome sequence of the viroid (370 nt) was determined by high-throughput sequencing as well as RT-PCR followed by cloning and Sanger sequencing. The terminal conserved region (TCR), central conserved region (CCR) upper strand, and CCR lower strand are conserved regions found in the viroid that are unique to the members of the genus Apscaviroid. Based on our findings and the demarcation criteria for viroids, the novel viroid, which we have tentatively named "grapevine yellow speckle viroid 3" is a putative new member of the genus Apscaviroid.


Asunto(s)
Genoma Viral , Secuenciación de Nucleótidos de Alto Rendimiento , Filogenia , Enfermedades de las Plantas , Viroides , Vitis , Vitis/virología , Viroides/genética , Viroides/aislamiento & purificación , Viroides/clasificación , Genoma Viral/genética , Enfermedades de las Plantas/virología , ARN Viral/genética , Secuenciación Completa del Genoma/métodos , Secuencia de Bases
3.
Int Microbiol ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39155336

RESUMEN

BACKGROUND: Transcriptome data from a plant sample frequently include numerous reads originating from RNA virus genomes that were concurrently isolated during RNA preparation. These high-throughput sequencing reads from the virus can be assembled to form a new sequence for the plant RNA genome. METHODS AND RESULTS: Here, we identify putative novel mitovirus, grapevine mitovirus 1 (GMV1) through high-throughput sequencing (HTS) of grapevine rootstocks (Vitis spp.), and the identified virus was confirmed using virus-specific primers in RT-PCR assay. The genomic RNA of GMV1 encodes complete open reading frame (ORF) of 2,496 nucleotides (nts) in length. RNA-dependent RNA polymerase (RdRp) encoded by the viral genome contained one RdRp conserved domain. BLASTx analysis of GMV1 genome showed sequence identity of 33.18-56.75% with the existing mitovirus sequences. Phylogenetic analysis based on genome sequences showed that GMV1 clustered in a distinct clade to other mitoviruses. CONCLUSION: Grapevine mitovirus 1 represents a newly discovered species within the Unuamitovirus genus of the Mitoviridae family, targeting fungal mitochondria. While the majority of recognized mitoviruses typically lack a functional RdRp as per the plant mitochondrial genetic code, GMV1 encodes a complete RdRp in accordance with both fungal and plant mitochondrial genetic codes.

4.
Hepatol Commun ; 8(8)2024 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-39023314

RESUMEN

Health care transition (HCT) is the process of changing from a pediatric to an adult model of care. Young adult pediatric recipients of liver transplant transferring from pediatric to adult health care services are highly vulnerable and subject to poor long-term outcomes. Barriers to successful transition are multifaceted. A comprehensive HCT program should be initiated early in pediatrics and continued throughout young adulthood, even after transfer of care has been completed. It is critical that pediatric and adult liver transplant providers establish a partnership to optimize care for these patients. Adult providers must recognize the importance of HCT and the need to continue the transition process following transfer. While this continued focus on HCT is essential, current literature has primarily offered guidance for pediatric providers. This position paper outlines a framework with a sample set of tools for the implementation of a standardized, multidisciplinary approach to HCT for adult transplant providers utilizing "The Six Core Elements of HCT." To implement more effective strategies and work to improve long-term outcomes for young adult patients undergoing liver transplant, HCT must be mandated as a routine part of posttransplant care. Increased advocacy efforts with the additional backing and support of governing organizations are required to help facilitate these practices.


Asunto(s)
Trasplante de Hígado , Transición a la Atención de Adultos , Humanos , Transición a la Atención de Adultos/normas , Adulto Joven , Adolescente , Niño , Adulto
5.
3 Biotech ; 14(6): 170, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38828101

RESUMEN

In the current study, high-throughput sequencing (HTS) was used to identify viruses associated with the Kinnow mandarin (Citrus reticulata) plants exhibiting yellow vein clearing, mottling, and chlorosis symptoms at experimental farm of ICAR-Indian Agricultural Research Institute, New Delhi, India. During November 2022, leaf samples of symptomatic and asymptomatic Kinnow mandarin trees were collected, subjected to HTS and one of the representative symptomatic samples was subjected to leaf-dip electron microscopy (EM). In the EM results, flexuous virus particles typical of mandarivirus were observed. Ribosomal RNA was depleted from total RNA of pooled samples and RNA sequencing was done using NovaSeq 6000. Host unaligned reads were de novo assembled into contigs, which were annotated through BLASTn using database of plant viruses/viroids reference genomes (NCBI). Results of assembled contigs revealed near-complete genomes of two mandariviruses, i.e., citrus yellow vein clearing virus (CYVCV) and citrus yellow mottle-associated virus (CiYMaV). The values of fragments per kilo base transcript length per million fragments mapped estimation indicated the dominance of CYVCV in HTS data and it was also confirmed through krona plot distribution of viruses in the pooled samples. A rapid and reliable duplex RT-PCR assay was also developed and standardized for the simultaneous detection of both CYVCV and CiYMaV in a pooled Kinnow mandarin sample. The developed duplex RT-PCR was then validated for the presence of these viruses in individual Kinnow mandarin samples. The specificity and sensitivity results confirmed that primers were highly specific to their targets and able to detect viruses up to 10-2 dilutions of RNA in standard and duplex RT-PCR. Therefore, the developed rapid duplex RT-PCR can be used for virus indexing and production of virus-free Kinnow mandarin plants for certification programs. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-024-04011-9.

6.
Indian J Otolaryngol Head Neck Surg ; 76(3): 2290-2294, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38883467

RESUMEN

Comparative evaluation of arterial blood gas in patients with stridor, before and after emergency tracheostomy. The present prospective study was conducted in tertiary care Centre from February 2022 to June 2023 on 42 patients who presented with stridor and underwent emergency tracheostomy in our department. After proper history taking and clinical examination, nonsurgical cause of stridor was ruled out. Patients were then classified on the basis of location of cause of stridor (whether oropharyngeal, hypo-pharyngeal, supra-glottic, glottic or sub-glottic). Immediately an arterial blood gas (ABG) analysis was done, and emergency tracheostomy was performed. Following tracheostomy, ABG analysis was done immediately, after 12 h and after 24 h. The mean age of presentation of stridor in our study was 65.02 ± 3.23 years, with male preponderance (Male: female ratio being 3.66:1). Most common etiology of stridor in our study was glottic carcinoma comprising 50%, and least common etiology of stridor was hypopharyngeal carcinoma, and subglottic stenosis comprising 2.4% each. There was statistically significant normalization of ABG in terms of pH, PO2, PCO2, HCO3. Mean pH, PO2, PCO2, and HCO3 before tracheostomy were 7.31, 74.8, 60.6, and 29.8 respectively. Mean pH, PO2, PCO2, HCO3, immediately after tracheostomy were7.38, 91.3, 48.4, and 27.4 respectively. After 12 h of tracheostomy, mean pH, PO2, PCO2, HCO3 were 7.41, 95.4, 42.7, 25.3 respectively. Mean pH, PO2, PCO2, HCO3 24 h after emergency tracheostomy were 7.441, 95.5, 42.8, 24.6 respectively. Emergency tracheostomy in stridor patients improves the acid base and ventilatory status, by relieving the obstruction as evidenced by statistically significant improvement in arterial blood gas values, and can be used as a diagnostic tool in upper airway obstruction.

7.
Autoimmunity ; 57(1): 2356089, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38770919

RESUMEN

Autoimmune hepatitis (AIH) is a chronic, inflammatory liver disease of unknown aetiology which requires lifelong immunosuppression. Most therapeutic and outcome studies of AIH have been conducted predominantly in Caucasian (European Ancestry, EA) cohorts, with the exclusion of African American (AA) patients due to inadequate sample size. It is known that AA patients have a severe phenotype of autoimmune diseases and demonstrate a poor response to conventional medical therapy. Understanding cellular and molecular pathways which determine AIH severity and progression in AA patients is likely to lead to the discovery of novel, personalised and better tolerated therapies. The aim of the study is to determine the distinct effector B cell phenotypes which contribute to disease severity and progression of AIH in AA children as compared to their EA cohorts. PBMCs were isolated from blood samples collected from patients visiting Children's Healthcare of Atlanta (CHOA) and were grouped into AA, (n = 12), EA, (n = 11) and controls (n = 12) and were processed for flow cytometry. Markers of B cell development, maturation and activation were assessed namely CD19, CD21, IgD, CD27, CD38, CD11c, CD24, CD138. AA children with AIH demonstrated an expansion of CD19 + ve, Activated Naïve (aN), (CD19+ IgD-/CD27- Double Negative (DN2) ([CD19+/IgD-/CD27++CD38++) cells. Plasmablasts were significantly higher along with Signalling Lymphocytic activation molecule F7 (SLAMF7). Unswitched memory [CD19+] IgD+CD27+ (USM) B cells were significantly contracted in AA patients with AIH. B cell phenotyping reveals a distinct profile in AA AIH patients with a major skewing towards the expansion of effector pathways which have been previously characterised in severe SLE in AA patients. These results suggest that the quantification and therapeutic target of B cell pathway could contribute substantially to the clinical approach to AIH especially in the AA population.


Asunto(s)
Linfocitos B , Hepatitis Autoinmune , Inmunoglobulina D , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral , Humanos , Hepatitis Autoinmune/inmunología , Hepatitis Autoinmune/sangre , Hepatitis Autoinmune/patología , Hepatitis Autoinmune/diagnóstico , Inmunoglobulina D/inmunología , Inmunoglobulina D/metabolismo , Niño , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/metabolismo , Masculino , Femenino , Adolescente , Linfocitos B/inmunología , Linfocitos B/metabolismo , Preescolar , Inmunofenotipificación , Subgrupos de Linfocitos B/inmunología , Subgrupos de Linfocitos B/metabolismo , Edad de Inicio , Biomarcadores
8.
J Stomatol Oral Maxillofac Surg ; : 101876, 2024 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-38636805

RESUMEN

This article has been withdrawn at the request of the authors. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/policies/article-withdrawal

9.
Aliment Pharmacol Ther ; 59(10): 1236-1247, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38462727

RESUMEN

BACKGROUND: Data on oral vancomycin for primary sclerosing cholangitis (PSC)-associated inflammatory bowel disease (IBD) are limited. AIMS: Using data from the Paediatric PSC Consortium, to examine the effect of vancomycin on IBD activity. METHODS: In this retrospective multi-centre cohort study, we matched vancomycin-treated and untreated patients (1:3) based on IBD duration at the time of primary outcome assessment. The primary outcome was Physician Global Assessment (PGA) of IBD clinical activity after 1 year (±6 months) of vancomycin. We used generalised estimating equations (GEE) to examine the association between vancomycin and PGA remission, adjusting for IBD type, severity and medication exposures. Secondary outcomes included serum labs and endoscopic remission (global rating of no activity) among those with available data and also analysed with GEE. RESULTS: 113 PSC-IBD patients received vancomycin (median age 12.7 years, 63% male). The matched cohort included 70 vancomycin-treated and 210 untreated patients. Vancomycin was associated with greater odds of IBD clinical remission (odds ratio [OR] 3.52, 95% CI 1.97-6.31; adjusted OR [aOR] 5.24, 95% CI 2.68-10.22). Benefit was maintained in sensitivity analyses restricted to non-transplanted patients and those with baseline moderate-severe PGA. Vancomycin was associated with increased odds of endoscopic remission (aOR 2.76, 95% CI 1.002-7.62; N = 101 with data), and with lower CRP (p = 0.03) and higher haemoglobin and albumin (both p < 0.01). CONCLUSION: Vancomycin was associated with greater odds of IBD clinical and endoscopic remission. Additional, preferably randomised, controlled studies are needed to characterise efficacy using objective markers of mucosal inflammation, and to examine safety and define optimal dosing.


Asunto(s)
Antibacterianos , Colangitis Esclerosante , Enfermedades Inflamatorias del Intestino , Vancomicina , Humanos , Vancomicina/administración & dosificación , Vancomicina/efectos adversos , Colangitis Esclerosante/tratamiento farmacológico , Colangitis Esclerosante/complicaciones , Femenino , Masculino , Estudios Retrospectivos , Niño , Adolescente , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Antibacterianos/efectos adversos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Enfermedades Inflamatorias del Intestino/complicaciones , Administración Oral , Resultado del Tratamiento , Índice de Severidad de la Enfermedad , Inducción de Remisión , Estudios de Cohortes
10.
Mol Biotechnol ; 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38366109

RESUMEN

Calanthe mild mosaic virus (CalMMV) infecting orchids is an important potyvirus which is known to cause mild leaf mosaic and flower colour-breaking symptoms in Calanthe and other orchid plants. The present study reports the production of polyclonal antibodies against CalMMV using bacterially expressed recombinant coat protein as immunogen, which in turn would be useful in routine indexing and screening of orchid germplasm. The coat protein (CP) gene (~ 807 bp) of CalMMV isolated from infected orchid sample was cloned in expression vector, pET-28a ( +) that yielded ~ 31 kDa fusion protein with Histidine tag (His6BP). The expression of fusion CP was confirmed through SDS-PAGE and Western blotting. The His6BP-CalMMV-CP obtained in soluble state after purification was used to immunize New Zealand white rabbit for the production of polyclonal antibodies (PAb). The PAb produced against the purified fusion protein successfully detected CAlMMV in the orchid samples at a dilution of 1:2000 in direct antigen-coated enzyme-linked immunosorbent assay (DAC-ELISA). This study presents the first report of Histidine tag (His6BP) fusion CalMMV-CP-based antibody production and its successful application in the identification of the virus in orchid plants. Outcome of this study will be helpful in routine certification programmes, screening of orchid germplasm and production of CalMMV-free planting materials of orchids.

11.
Curr Microbiol ; 81(4): 103, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38386082

RESUMEN

Citrus is an economically important fruit crop, belongs to family Rutaceae, cultivated commercially in over 130 countries, which holds a leading profitable position in the international market. The most important citrus varieties are mandarins, oranges, lemons, sweet limes, grapefruits and pomelos. Citrus yellow vein clearing virus (CYVCV) is an important graft transmissible plant pathogen known to reduce productivity of citrus fruits due to its predominant association and widespread occurrence. Requirement of fast, reliable, efficient & economical CYVCV indexing assay is a prerequisite for production of healthy planting material. Currently, nucleic acid isolation and thermal cycler-based assay available for CYVCV indexing is a cumbersome lab intensive method. The present study was undertaken to develop and validate reverse transcription-recombinase polymerase amplification (RT-RPA) assay requiring no tedious RNA isolation, separate cDNA synthesis and costlier instrument like thermo-cycler. Optimized RT-RPA assay was able to amplify CYVCV up to 10-7 dilution (equivalent to 0.1 pg/µl) with the prepared templates of both RNA and crude saps and showed higher sensitivity in detection of CYVCV infection in field samples as compared to the conventional RT-PCR. Developed RT-RPA assay showed high specificity without any cross-reaction with other citrus pathogens (Indian citrus ringspot virus, citrus yellow mosaic virus, citrus tristeza virus, citrus exocortis viroid and huanglongbing). RT-RPA using crude leaf sap as template is quite simple, robust, highly sensitive, time and cost effective; therefore, it can be used in resource constrained laboratories as screening tool, for field surveys and on-site testing programs in farms, nurseries and biosecurity. Present study, first time reports the development, optimization and validation of crude sap-based RT-RPA assay for the detection of CYVCV infection in citrus plants namely; Kinnow mandarin, Mosambi and Grape fruit.


Asunto(s)
Citrus , Recombinasas , Recombinasas/genética , Bioensayo , Granjas , ARN
12.
Transplantation ; 108(4): 940-946, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37831642

RESUMEN

BACKGROUND: The social determinants of health contribute to adverse post-liver transplant outcomes. Identifying unmet social risks may enable transplant teams to improve long-term outcomes for at-risk children. However, providers may feel uncomfortable asking about household-level social risks in the posttransplant period because they might make their patients/families uncomfortable. METHODS: We conducted a mixed-methods analysis of caregiver participants (ie, parents/guardians of pediatric liver transplant recipients) in the Social and Contextual Impact on Children Undergoing Liver Transplantation study to assess their perceptions of provider-based social risk screening. Participants (N = 109) completed a 20-min social determinants of health questionnaire that included questions on the acceptability of being asked intimate social risk questions. A subset of participants (N = 37) engaged in an in-depth qualitative interview to share their perceptions of social risk screening. RESULTS: Of 109 participants across 9 US transplant centers, 60% reported financial strain and 30% reported at least 1 material economic hardship (eg, food insecurity, housing instability). Overall, 65% of respondents reported it very or somewhat appropriate and 25% reported being neutral to being screened for social risks in a liver transplant setting. In qualitative analyses, participants reported trust in the providers and a clear understanding of the intention of the screening as prerequisites for liver transplant teams to perform social risk screening. CONCLUSIONS: Only a small minority of caregivers found social risk screening unacceptable. Pediatric liver transplant programs should implement routine social risk screening and prioritize the patient and family voices when establishing a screening program to ensure successful implementation.


Asunto(s)
Cuidadores , Trasplante de Hígado , Humanos , Niño , Trasplante de Hígado/efectos adversos , Vivienda , Pobreza , Determinantes Sociales de la Salud
13.
Indian J Otolaryngol Head Neck Surg ; 75(4): 3679-3685, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37974701

RESUMEN

Comparative evaluation of early and late tracheostomy outcomes in mechanically ventilated patients. The present retrospective study was conducted in Government medical college Jammu from April 2021 to November 2022 on 111 tracheotomised patient in intensive care unit. All tracheostomies with in 10 days of intubation were grouped as early tracheostomy (ET) group and all those done after 10 days were grouped as LATE TRACHEOSTOMY (LT) group. APACHE II score at the time of intensive care unit admission of all included tracheotomised patients was noted. Data regarding mortality, duration of mechanical ventilation and length of stay in intensive care unit (ICU) was studied. Mean age of presentation was 41.5 ± 15.7 yrs, with male preponderance. Out of 111 patients, 57 patients underwent early tracheostomy and 54 underwent late TRACHEOSTOMY. In APACHE II, < 25 category-short term mortality was 4 in ET and 5 in LT; long term mortality in ET was 4 and 10 in LT; average days of mechanical ventilation were 11.2 in ET and 3 in LT; average stay in ICU was 18 days in ET and 61 days in LT. in APACHE II > 25-short term mortality was 4 in ET and 5 in LT; long term mortality in ET was 3 and 9 in LT. Average days of mechanical ventilation were 10.8 in ET and 57 in LT; average stay in ICU was 24 days in ET and 79 days in LT. Early tracheostomy is superior to late Tracheostomy in terms of mortality, number of days of mechanical ventilation and the duration of intensive care unit stay.

14.
JAMA Netw Open ; 6(10): e2337602, 2023 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-37824141

RESUMEN

Importance: Live vaccines (measles-mumps-rubella [MMR] and varicella-zoster virus [VZV]) have not been recommended after solid organ transplant due to concern for inciting vaccine strain infection in an immunocompromised host. However, the rates of measles, mumps, and varicella are rising nationally and internationally, leaving susceptible immunocompromised children at risk for life-threating conditions. Objective: To determine the safety and immunogenicity of live vaccines in pediatric liver and kidney transplant recipients. Design, Setting, and Participants: This cohort study included select pediatric liver and kidney transplant recipients who had not completed their primary MMR and VZV vaccine series and/or who displayed nonprotective serum antibody levels at enrollment between January 1, 2002, and February 28, 2023. Eligibility for live vaccine was determined by individual US pediatric solid organ transplant center protocols. Exposures: Exposure was defined as receipt of a posttransplant live vaccine. Transplant recipients received 1 to 3 doses of MMR vaccine and/or 1 to 3 doses of VZV vaccine. Main Outcome and Measure: Safety data were collected following each vaccination, and antibody levels were obtained at 0 to 3 months and 1 year following vaccination. Comparisons were performed using Mann-Whitney U test, and factors associated with development of postvaccination protective antibodies were explored using univariate analysis. Results: The cohort included 281 children (270 [96%] liver, 9 [3%] kidney, 2 [1%] liver-kidney recipients) from 18 centers. The median time from transplant to enrollment was 6.3 years (IQR, 3.4-11.1 years). The median age at first posttransplant vaccine was 8.9 years (IQR, 4.7-13.8 years). A total of 202 of 275 (73%) children were receiving low-level monotherapy immunosuppression at the time of vaccination. The majority of children developed protective antibodies following vaccination (107 of 149 [72%] varicella, 130 of 152 [86%] measles, 100 of 120 [83%] mumps, and 124 of 125 [99%] rubella). One year post vaccination, the majority of children who initially mounted protective antibodies maintained this protection (34 of 44 [77%] varicella, 45 of 49 [92%] measles, 35 of 42 [83%] mumps, 51 of 54 [94%] rubella). Five children developed clinical varicella, all of which resolved within 1 week. There were no cases of measles or rubella and no episodes of graft rejection within 1 month of vaccination. There was no association between antibody response and immunosuppression level at the time of vaccination. Conclusions and Relevance: The findings suggest that live vaccinations may be safe and immunogenic after solid organ transplant in select pediatric recipients and can offer protection against circulating measles, mumps, and varicella.


Asunto(s)
Varicela , Sarampión , Paperas , Rubéola (Sarampión Alemán) , Vacunas Virales , Niño , Humanos , Preescolar , Adolescente , Varicela/prevención & control , Vacuna contra la Varicela/efectos adversos , Vacunas Combinadas , Receptores de Trasplantes , Estudios de Cohortes , Rubéola (Sarampión Alemán)/prevención & control , Sarampión/prevención & control , Vacunas Atenuadas/efectos adversos
15.
J Physiol ; 601(17): 3739-3764, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37428651

RESUMEN

Calmodulin (CaM) is a highly conserved mediator of calcium (Ca2+ )-dependent signalling and modulates various cardiac ion channels. Genotyping has revealed several CaM mutations associated with long QT syndrome (LQTS). LQTS patients display prolonged ventricular recovery times (QT interval), increasing their risk of incurring life-threatening arrhythmic events. Loss-of-function mutations to Kv7.1 (which drives the slow delayed rectifier potassium current, IKs, a key ventricular repolarising current) are the largest contributor to congenital LQTS (>50% of cases). CaM modulates Kv7.1 to produce a Ca2+ -sensitive IKs, but little is known about the consequences of LQTS-associated CaM mutations on Kv7.1 function. Here, we present novel data characterising the biophysical and modulatory properties of three LQTS-associated CaM variants (D95V, N97I and D131H). We showed that mutations induced structural alterations in CaM and reduced affinity for Kv7.1, when compared with wild-type (WT). Using HEK293T cells expressing Kv7.1 channel subunits (KCNQ1/KCNE1) and patch-clamp electrophysiology, we demonstrated that LQTS-associated CaM variants reduced current density at systolic Ca2+ concentrations (1 µm), revealing a direct QT-prolonging modulatory effect. Our data highlight for the first time that LQTS-associated perturbations to CaM's structure impede complex formation with Kv7.1 and subsequently result in reduced IKs. This provides a novel mechanistic insight into how the perturbed structure-function relationship of CaM variants contributes to the LQTS phenotype. KEY POINTS: Calmodulin (CaM) is a ubiquitous, highly conserved calcium (Ca2+ ) sensor playing a key role in cardiac muscle contraction. Genotyping has revealed several CaM mutations associated with long QT syndrome (LQTS), a life-threatening cardiac arrhythmia syndrome. LQTS-associated CaM variants (D95V, N97I and D131H) induced structural alterations, altered binding to Kv7.1 and reduced IKs. Our data provide a novel mechanistic insight into how the perturbed structure-function relationship of CaM variants contributes to the LQTS phenotype.


Asunto(s)
Calmodulina , Síndrome de QT Prolongado , Humanos , Calmodulina/genética , Calmodulina/metabolismo , Calcio/metabolismo , Células HEK293 , Síndrome de QT Prolongado/genética , Mutación , Canal de Potasio KCNQ1/genética
16.
Front Plant Sci ; 14: 1151471, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36968414

RESUMEN

Geminiviruses are known to infect several fields and horticultural crops around the globe. Grapevine geminivirus A (GGVA) was reported in the United States in 2017, and since then, it has been reported in several countries. The complete genome recovered through high-throughput sequencing (HTS)-based virome analysis in Indian grapevine cultivars had all of the six open reading frames (ORFs) and a conserved nonanucleotide sequence 5'-TAATATTAC-3' similar to all other geminiviruses. Recombinase polymerase amplification (RPA), an isothermal amplification technique, was developed for the detection of GGVA in grapevine samples employing crude sap lysed in 0.5 M NaOH solution and compared with purified DNA/cDNA as a template. One of the key advantages of this assay is that it does not require any purification or isolation of the viral DNA and can be performed in a wide range of temperatures (18°C-46°C) and periods (10-40 min), which makes it a rapid and cost-effective method for the detection of GGVA in grapevine. The developed assay has a sensitivity up to 0.1 fg µl-1 using crude plant sap as a template and detected GGVA in several grapevine cultivars of a major grapevine-growing area. Because of its simplicity and rapidity, it can be replicated for other DNA viruses infecting grapevine and will be a very useful technique for certification and surveillance in different grapevine-growing regions of the country.

17.
Lett Appl Microbiol ; 76(2)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36794889

RESUMEN

Leek yellow stripe virus (LYSV) is one of the most important potyviruses, associated with garlic throughout the world, including India. LYSV causes stunting and yellow streaks in garlic and leek leaves and with other coinfecting viruses leading to severe symptom expression and yield reduction. In this study, we have made the first reported attempt to produce specific polyclonal antibodies to LYSV using expressed recombinant coat protein (CP), which would be useful for screening and routine indexing of the garlic germplasm. The CP gene was cloned, sequenced, and further subcloned in pET-28a(+) expression vector, which yielded ∼35 kDa fusion protein. The fusion protein was obtained in insoluble fraction after purification and its identity was confirmed by SDS-PAGE and western blotting. The purified protein was used as immunogen for production of polyclonal antisera in New Zealand white rabbit. Antisera raised, was able to recognize the corresponding recombinant proteins in western blotting, immunosorbent electron microscopy and dot immunobinding assay (DIBA). Developed antisera to LYSV (titer 1:2000) was used for screening of 21 garlic accessions in antigen coated plate enzyme-linked immunosorbent assay (ACP-ELISA) and 16 accessions were found positive for LYSV, indicating its widespread presence within the collection tested. To the best of our knowledge, this is the first report of a polyclonal antiserum against the in-vitro expressed CP of LYSV and its successful application in diagnosis of LYSV in garlic accessions in India.


Asunto(s)
Ajo , Potyvirus , Animales , Conejos , Cebollas , Escherichia coli/genética , Secuencia de Bases , Proteínas Recombinantes/genética , Ajo/genética , Potyvirus/genética , Sueros Inmunes/genética
18.
J Biol Chem ; 299(1): 102777, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36496072

RESUMEN

Long QT syndrome (LQTS) is a human inherited heart condition that can cause life-threatening arrhythmia including sudden cardiac death. Mutations in the ubiquitous Ca2+-sensing protein calmodulin (CaM) are associated with LQTS, but the molecular mechanism by which these mutations lead to irregular heartbeats is not fully understood. Here, we use a multidisciplinary approach including protein biophysics, structural biology, confocal imaging, and patch-clamp electrophysiology to determine the effect of the disease-associated CaM mutation E140G on CaM structure and function. We present novel data showing that mutant-regulated CaMKIIδ kinase activity is impaired with a significant reduction in enzyme autophosphorylation rate. We report the first high-resolution crystal structure of a LQTS-associated CaM variant in complex with the CaMKIIδ peptide, which shows significant structural differences, compared to the WT complex. Furthermore, we demonstrate that the E140G mutation significantly disrupted Cav1.2 Ca2+/CaM-dependent inactivation, while cardiac ryanodine receptor (RyR2) activity remained unaffected. In addition, we show that the LQTS-associated mutation alters CaM's Ca2+-binding characteristics, secondary structure content, and interaction with key partners involved in excitation-contraction coupling (CaMKIIδ, Cav1.2, RyR2). In conclusion, LQTS-associated CaM mutation E140G severely impacts the structure-function relationship of CaM and its regulation of CaMKIIδ and Cav1.2. This provides a crucial insight into the molecular factors contributing to CaM-mediated arrhythmias with a central role for CaMKIIδ.


Asunto(s)
Canales de Calcio Tipo L , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina , Calmodulina , Síndrome de QT Prolongado , Humanos , Arritmias Cardíacas/genética , Arritmias Cardíacas/fisiopatología , Calcio/metabolismo , Canales de Calcio Tipo L/genética , Canales de Calcio Tipo L/metabolismo , Calmodulina/genética , Calmodulina/metabolismo , Síndrome de QT Prolongado/genética , Miocitos Cardíacos/metabolismo , Canal Liberador de Calcio Receptor de Rianodina/genética , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/genética , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Mutación , Estructura Secundaria de Proteína/genética , Unión Proteica/genética , Cristalografía
19.
Pediatr Transplant ; 27(1): e14409, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36272132

RESUMEN

BACKGROUND: Patient-reported outcome measures (PROMs) are not routinely used in clinical care by pediatric liver transplant (LT) teams. The Starzl Network for Excellence in Pediatric Transplantation (SNEPT) assessed feasibility of using a disease-specific Quality of Life (QoL) questionnaire in the ambulatory setting at 10 SNEPT sites. METHODS: A mixed methods feasibility project assessing administration processes, barriers, and user experiences with the Pediatric Liver Transplant Quality of Life (PeLTQL) tool. Iterative processes sought stakeholder feedback across four phases (Pilot, Extended Pilot, Development of a Mobile App PeLTQL version, and Pilot App use). RESULTS: A total of 149 patient-parent dyads completed the PeLTQL during LT clinic follow-up. Clinicians, parents, and patients evaluated and reported on feasibility of operationalization. Only two of 10 SNEPT sites continued PeLTQL administration after the initial two pilot phases. Reasons include limited clinical time and available personnel aggravated by the COVID-19 pandemic. In response, a mobile application version of the PeLTQL was initiated. Providing PeLTQL responses electronically was "very easy" or "easy" as reported by 96% (22/23) parents. CONCLUSIONS: Administration of a PROM into post-pediatric LT clinical care was feasible, but ongoing utilization stalled. Use of a mobile app towards facilitating completion of the PeLTQL outside of clinic hours may address the time and work-flow barriers identified.


Asunto(s)
COVID-19 , Trasplante de Hígado , Niño , Humanos , Calidad de Vida , Estudios de Factibilidad , Pandemias , Medición de Resultados Informados por el Paciente
20.
Sci Rep ; 12(1): 18663, 2022 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-36333377

RESUMEN

Pediatric liver transplantation rejection affects 20% of children. Currently, liver biopsy, expensive and invasive, is the best method of diagnosis. Discovery and validation of clinical biomarkers from blood or other biospecimens would improve clinical care. For this study, stored plasma samples were utilized from two cross-sectional cohorts of liver transplant patients at Children's Healthcare of Atlanta. High resolution metabolic profiling was completed using established methods. Children with (n = 18) or without (n = 25) acute cellular rejection were included in the analysis (n = 43 total). The mean age of these racially diverse cohorts ranged from 12.6 years in the rejection group and 13.6 years in the no rejection group. Linear regression provided 510 significantly differentiating metabolites between groups, and OPLS-DA showed 145 metabolites with VIP > 2. A total of 95 overlapping significant metabolites between OPLS-DA and linear regression analyses were detected. Pathway analysis (p < 0.05) showed bile acid biosynthesis and tryptophan metabolism as the top two differentiating pathways. Network analysis also identified tryptophan and clustered with liver enzymes and steroid use. We conclude metabolic profiling of plasma from children with acute liver transplant rejection demonstrates > 500 significant metabolites. This result suggests that development of a non-invasive biomarker-based test is possible for rejection screening.


Asunto(s)
Rechazo de Injerto , Trasplante de Hígado , Humanos , Niño , Rechazo de Injerto/patología , Estudios Transversales , Triptófano , Metabolómica/métodos , Hígado/patología , Biomarcadores , Complicaciones Posoperatorias/patología
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