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1.
Lancet Glob Health ; 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39222652

RESUMEN

BACKGROUND: Uganda has had seven Ebola disease outbreaks, between 2000 and 2022. On Sept 20, 2022, the Ministry of Health declared a Sudan virus disease outbreak in Mubende District, Central Uganda. We describe the epidemiological characteristics and transmission dynamics. METHODS: For this descriptive study, cases were classified as suspected, probable, or confirmed using Ministry of Health case definitions. We investigated all reported cases to obtain data on case-patient demographics, exposures, and signs and symptoms, and identified transmission chains. We conducted a descriptive epidemiological study and also calculated basic reproduction number (Ro) estimates. FINDINGS: Between Aug 8 and Nov 27, 2022, 164 cases (142 confirmed, 22 probable) were identified from nine (6%) of 146 districts. The median age was 29 years (IQR 20-38), 95 (58%) of 164 patients were male, and 77 (47%) patients died. Symptom onsets ranged from Aug 8 to Nov 27, 2022. The case fatality rate was highest in children younger than 10 years (17 [74%] of 23 patients). Fever (135 [84%] of 160 patients), vomiting (93 [58%] patients), weakness (89 [56%] patients), and diarrhoea (81 [51%] patients) were the most common symptoms; bleeding was uncommon (21 [13%] patients). Before outbreak identification, most case-patients (26 [60%] of 43 patients) sought care at private health facilities. The median incubation was 6 days (IQR 5-8), and median time from onset to death was 10 days (7-23). Most early cases represented health-care-associated transmission (43 [26%] of 164 patients); most later cases represented household transmission (109 [66%]). Overall Ro was 1·25. INTERPRETATION: Despite delayed detection, the 2022 Sudan virus disease outbreak was rapidly controlled, possibly thanks to a low Ro. Children (aged <10 years) were at the highest risk of death, highlighting the need for targeted interventions to improve their outcomes during Ebola disease outbreaks. Initial care-seeking occurred at facilities outside the government system, showing a need to ensure that private and public facilities receive training to identify possible Ebola disease cases during an outbreak. Health-care-associated transmission in private health facilities drove the early outbreak, suggesting gaps in infection prevention and control. FUNDING: None.

2.
BMC Infect Dis ; 24(1): 520, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38783244

RESUMEN

BACKGROUND: On 20 September 2022, Uganda declared its fifth Sudan virus disease (SVD) outbreak, culminating in 142 confirmed and 22 probable cases. The reproductive rate (R) of this outbreak was 1.25. We described persons who were exposed to the virus, became infected, and they led to the infection of an unusually high number of cases during the outbreak. METHODS: In this descriptive cross-sectional study, we defined a super-spreader person (SSP) as any person with real-time polymerase chain reaction (RT-PCR) confirmed SVD linked to the infection of ≥ 13 other persons (10-fold the outbreak R). We reviewed illness narratives for SSPs collected through interviews. Whole-genome sequencing was used to support epidemiologic linkages between cases. RESULTS: Two SSPs (Patient A, a 33-year-old male, and Patient B, a 26-year-old male) were identified, and linked to the infection of one probable and 50 confirmed secondary cases. Both SSPs lived in the same parish and were likely infected by a single ill healthcare worker in early October while receiving healthcare. Both sought treatment at multiple health facilities, but neither was ever isolated at an Ebola Treatment Unit (ETU). In total, 18 secondary cases (17 confirmed, one probable), including three deaths (17%), were linked to Patient A; 33 secondary cases (all confirmed), including 14 (42%) deaths, were linked to Patient B. Secondary cases linked to Patient A included family members, neighbours, and contacts at health facilities, including healthcare workers. Those linked to Patient B included healthcare workers, friends, and family members who interacted with him throughout his illness, prayed over him while he was nearing death, or exhumed his body. Intensive community engagement and awareness-building were initiated based on narratives collected about patients A and B; 49 (96%) of the secondary cases were isolated in an ETU, a median of three days after onset. Only nine tertiary cases were linked to the 51 secondary cases. Sequencing suggested plausible direct transmission from the SSPs to 37 of 39 secondary cases with sequence data. CONCLUSION: Extended time in the community while ill, social interactions, cross-district travel for treatment, and religious practices contributed to SVD super-spreading. Intensive community engagement and awareness may have reduced the number of tertiary infections. Intensive follow-up of contacts of case-patients may help reduce the impact of super-spreading events.


Asunto(s)
Brotes de Enfermedades , Humanos , Uganda/epidemiología , Masculino , Estudios Transversales , Adulto , Femenino , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/virología , Secuenciación Completa del Genoma , Ebolavirus/genética , Ebolavirus/aislamiento & purificación
3.
Int J Infect Dis ; 145: 107073, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38670481

RESUMEN

OBJECTIVES: Early isolation and care for Ebola disease patients at Ebola Treatment Units (ETU) curb outbreak spread. We evaluated time to ETU entry and associated factors during the 2022 Sudan virus disease (SVD) outbreak in Uganda. METHODS: We included persons with RT-PCR-confirmed SVD with onset September 20-November 30, 2022. We categorized days from symptom onset to ETU entry ("delays") as short (≤2), moderate (3-5), and long (≥6); the latter two were "delayed isolation." We categorized symptom onset timing as "earlier" or "later," using October 15 as a cut-off. We assessed demographics, symptom onset timing, and awareness of contact status as predictors for delayed isolation. We explored reasons for early vs late isolation using key informant interviews. RESULTS: Among 118 case-patients, 25 (21%) had short, 43 (36%) moderate, and 50 (43%) long delays. Seventy-five (64%) had symptom onset later in the outbreak. Earlier symptom onset increased risk of delayed isolation (crude risk ratio = 1.8, 95% confidence interval (1.2-2.8]). Awareness of contact status and SVD symptoms, and belief that early treatment-seeking was lifesaving facilitated early care-seeking. Patients with long delays reported fear of ETUs and lack of transport as contributors. CONCLUSION: Delayed isolation was common early in the outbreak. Strong contact tracing and community engagement could expedite presentation to ETUs.


Asunto(s)
Brotes de Enfermedades , Fiebre Hemorrágica Ebola , Humanos , Uganda/epidemiología , Masculino , Femenino , Adulto , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/terapia , Persona de Mediana Edad , Adulto Joven , Tiempo de Tratamiento , Adolescente , Sudán/epidemiología , Factores de Tiempo , Aislamiento de Pacientes
4.
Epilepsy Res ; 200: 107280, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38183688

RESUMEN

PURPOSE: Plant-derived highly purified cannabidiol (CBD) reduced the frequency of seizures associated with Lennox-Gastaut syndrome (LGS) and Dravet syndrome (DS) and improved the overall condition of patients in placebo-controlled phase 3 clinical trials. Anecdotal reports also suggest a positive effect on nonseizure outcomes. In this study, we aimed to identify, through a caregiver survey which nonseizure outcomes were most likely to change in these patients. METHODS: The BEhavior, COgnition, and More with Epidiolex® (BECOME) was a 20-minute, cross-sectional, online survey that was developed with extensive input from caregivers, healthcare professionals, and epilepsy researchers, and was based on questions from validated measures and previously published caregiver reports. US-based caregivers (from Jazz Pharmaceuticals patient/caregiver database) of people with LGS or DS who were treated with CBD (Epidiolex®, 100 mg/mL oral solution) for ≥3 months were asked to compare the past month to the period before CBD initiation and rate their impression of changes using symmetrical Likert scales. RESULTS: A total of 498 caregivers (97% parents) of patients with LGS (80%) or DS (20%) completed the survey. Mean (range) age of patients was 16 (1-73) years, and 52% were male. Patients were taking a median CBD dose of 14 mg/kg/d and median 4 concomitant antiseizure medications. A large proportion of respondents reported improvements in ≥1 survey question for all nonseizure-related domains: alertness, cognition, and executive function (85%); emotional functioning (82%); language and communication (79% in nonverbal patients and 74% in verbal); activities of daily living (51%); sleep (51%); and physical functioning (46%). Respondents reported improvements in seizure-related domains, including overall seizure frequency (85%), overall seizure severity (76%), seizure-free days per week for ≥1 seizure type (67%), and seizure freedom during the past month (16%). The majority of respondents who reported reduction in seizure frequency also reported improvements in nonseizure outcomes domains (51-80%). However, improvements in nonseizure outcomes (18-56%) were also reported in patients who either had no change or worsening of seizure frequency. CONCLUSIONS: This survey characterized and quantified caregiver impression of changes in the seizure and nonseizure outcomes in patients taking add-on CBD treatment. Overall, 93% of caregivers reported planning to continue CBD treatment, primarily because of reduced seizure burden but also because of improvements in nonseizure-related outcomes. Despite the limitations that are associated with a retrospective survey-based study design, these results support further evaluation of the effect of CBD treatment on nonseizure outcomes among patients with LGS or DS.


Asunto(s)
Cannabidiol , Epilepsias Mioclónicas , Síndrome de Lennox-Gastaut , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Cannabidiol/uso terapéutico , Cannabidiol/efectos adversos , Síndrome de Lennox-Gastaut/tratamiento farmacológico , Síndrome de Lennox-Gastaut/complicaciones , Cuidadores , Actividades Cotidianas , Estudios Transversales , Estudios Retrospectivos , Anticonvulsivantes/efectos adversos , Epilepsias Mioclónicas/tratamiento farmacológico , Epilepsias Mioclónicas/complicaciones , Convulsiones/tratamiento farmacológico , Encuestas y Cuestionarios , Medición de Resultados Informados por el Paciente
5.
J Org Chem ; 89(2): 1256-1263, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38194284

RESUMEN

The rapid synthesis of a range of enantioenriched allylic esters is enabled by a new 3-component catalytic enantioselective 1,2-carboesterification of readily available dienes with carboxylic acids and potassium alkyltrifluoroborates. The chiral copper catalyst, formed in situ from Cu(OTf)2 and (4S,4'S)-2,2'-(cyclopentane-1,1-diyl)bis(4-phenyl-4,5-dihydrooxazole), is implicated in both the generation of alkyl radicals from the alkyltrifluoroborates as well as the enantioselective formation of C-O bonds. Potassium salts of primary and secondary alkyltrifluoroborates as well as several benzylic trifluoroborates, tert-butyltrifluoroborate, and phenyltrifluoroborate participate in the reaction. The regioselectivity and enantioselectivity are strongly impacted by variations in all of the reaction components, which in turn are thought to impact the C-O bond-forming reductive elimination from a [Cu(III)] intermediate.

6.
Gene ; 895: 148001, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-37977314

RESUMEN

Demand for maize oil is progressively increasing due to its diverse industrial applications, aside from its primary role in human nutrition and animal feed. Oil content and composition are two crucial determinants of maize oil in the international market. As kernel oil in maize is a complex quantitative trait, improving this trait presents a challenge for plant breeders and biotechnologists. Here, we characterized a set of 292 diverse maize inbreds of both indigenous and exotic origin by exploiting functional polymorphism of the dgat1-2, fatb, ge2, and wri1a genes governing kernel oil in maize. Genotyping using gene-based functional markers revealed a lower frequencies of dgat1-2 (0.15) and fatb (0.12) mutant alleles and a higher frequencies of wild-type alleles (Dgat1-2: 0.85; fatB: 0.88). The favorable wri1a allele was conserved across genotypes, while its wild-type allele (WRI1a) was not detected. In contrast, none of the genotypes possessed the ge2 favorable allele. The frequency of favorable alleles of both dgat1-2 and fatb decreased to 0.03 when considered together. Furthermore, pairwise protein-protein interactions among target gene products were conducted to understand the effect of one protein on another and their responses to kernel oil through functional enrichments. Thus, the identified maize genotypes with dgat1-2, fatb, and wri1a favourable alleles, along with insights gained through the protein-protein association network, serve as prominent and unique genetic resources for high-oil maize breeding programs. This is the first comprehensive report on the functional characterization of diverse genotypes at the molecular and protein levels.


Asunto(s)
Aceite de Maíz , Zea mays , Humanos , Zea mays/genética , Zea mays/metabolismo , Aceite de Maíz/genética , Aceite de Maíz/metabolismo , Ácidos Grasos/genética , Ácidos Grasos/metabolismo , Fitomejoramiento , Marcadores Genéticos , Alelos
8.
J Am Chem Soc ; 145(25): 13715-13729, 2023 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-37327484

RESUMEN

Alkene aminooxygenation and dioxygenation reactions that result in carbonyl products are uncommon, and protocols that control absolute stereochemistry are rare. We report herein catalytic enantioselective alkene aminooxygenation and dioxygenation that directly provide enantioenriched 2-formyl saturated heterocycles under aerobic conditions. Cyclization of substituted 4-pentenylsulfonamides, catalyzed by readily available chiral copper complexes and employing molecular oxygen as both oxygen source and stoichiometric oxidant, directly provides chiral 2-formyl pyrrolidines efficiently. Reductive or oxidative workup of these aldehydes provides their respective amino alcohols or amino acids (unnatural prolines). Enantioselective synthesis of an indoline and isoquinolines is also demonstrated. Concurrently, cyclization of various alkenols under similar conditions provides 2-formyl tetrahydrofurans, phthalans, isochromans, and morpholines. The nature of the copper ligands, the concentration of molecular oxygen, and the reaction temperature all impact the product distribution. Chiral nitrogen and oxygen heterocycles are common components of bioactive small molecules, and these enabling technologies provide access to saturated heterocycles functionalized with ready-to-use carbonyl electrophiles.

9.
BMC Health Serv Res ; 23(1): 441, 2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37143093

RESUMEN

BACKGROUND: The COVID-19 pandemic overwhelmed the capacity of health facilities globally, emphasizing the need for readiness to respond to rapid increases in cases. The first wave of COVID-19 in Uganda peaked in late 2020 and demonstrated challenges with facility readiness to manage cases. The second wave began in May 2021. In June 2021, we assessed the readiness of health facilities in Uganda to manage the second wave of COVID-19. METHODS: Referral hospitals managed severe COVID-19 patients, while lower-level health facilities screened, isolated, and managed mild cases. We assessed 17 of 20 referral hospitals in Uganda and 71 of 3,107 lower-level health facilities, selected using multistage sampling. We interviewed health facility heads in person about case management, coordination and communication and reporting, and preparation for the surge of COVID-19 during first and the start of the second waves of COVID-19, inspected COVID-19 treatment units (CTUs) and other service delivery points. We used an observational checklist to evaluate capacity in infection prevention, medicines, personal protective equipment (PPE), and CTU surge capacity. We used the "ReadyScore" criteria to classify readiness levels as > 80% ('ready'), 40-80% ('work to do'), and < 40% ('not ready') and tailored the assessments to the health facility level. Scores for the lower-level health facilities were weighted to approximate representativeness for their health facility type in Uganda. RESULTS: The median (interquartile range (IQR)) readiness scores were: 39% (IQR: 30, 51%) for all health facilities, 63% (IQR: 56, 75%) for referral hospitals, and 32% (IQR: 24, 37%) for lower-level facilities. Of 17 referral facilities, two (12%) were 'ready' and 15 (88%) were in the "work to do" category. Fourteen (82%) had an inadequate supply of medicines, 12 (71%) lacked adequate supply of oxygen, and 11 (65%) lacked space to expand their CTU. Fifty-five (77%) lower-level health facilities were "not ready," and 16 (23%) were in the "work to do" category. Seventy (99%) lower-level health facilities lacked medicines, 65 (92%) lacked PPE, and 53 (73%) lacked an emergency plan for COVID-19. CONCLUSION: Few health facilities were ready to manage the second wave of COVID-19 in Uganda during June 2021. Significant gaps existed for essential medicines, PPE, oxygen, and space to expand CTUs. The Uganda Ministry of Health utilized our findings to set up additional COVID-19 wards in hospitals and deliver medicines and PPE to referral hospitals. Adequate readiness for future waves of COVID-19 requires additional support and action in Uganda.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , COVID-19 , Humanos , Uganda/epidemiología , Pandemias , COVID-19/epidemiología , COVID-19/terapia , Instituciones de Salud
10.
Molecules ; 27(22)2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36431769

RESUMEN

MDM2 and MDM4 are cancer drug targets validated in multiple models for p53-based cancer therapies. The RING domains of MDM2 and non-p53-binder MDM2 splice isoforms form RING domain heterodimer polyubiquitin E3 ligases with MDM4, which regulate p53 stability in vivo and promote tumorigenesis independent of p53. Despite the importance of the MDM2 RING domain in p53 regulation and cancer development, small molecule inhibitors targeting the E3 ligase activity of MDM2-MDM4 are poorly explored. Here, we describe the synthesis and characterization of quinolinol derivatives for the identification of analogs that are capable of targeting the MDM2-MDM4 heterodimer E3 ligase and inducing apoptosis in cells. The structure-activity-relationship (SAR) study identified structural moieties critical for the inhibitory effects toward MDM2-MDM4 E3 ligase, the targeted degradation of MDM4 and FTH1 in cells, and anti-proliferation activity. Lead optimization led to the development of compound MMRi71 with improved activity. In addition to accumulating p53 proteins in wt-p53 bearing cancer cells as expected of any MDM2 inhibitors, MMRi71 effectively kills p53-null leukemia cells, an activity that conventional MDM2-p53 disrupting inhibitors lack. This study provides a prototype structure for developing MDM4/FTH1 dual-targeting inhibitors as potential cancer therapeutics.


Asunto(s)
Leucemia , Neoplasias , Humanos , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteolisis , Proteínas Proto-Oncogénicas/química , Ubiquitina-Proteína Ligasas/metabolismo , Apoptosis , Leucemia/tratamiento farmacológico , Proteínas de Ciclo Celular/metabolismo , Ferritinas , Oxidorreductasas/metabolismo
11.
J Psychiatr Res ; 155: 263-268, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36126396

RESUMEN

BACKGROUND: Anxiety sensitivity involves the fear of anxiety-related symptoms and can exacerbate both major depressive disorder and posttraumatic stress disorder (PTSD) symptoms. However, it is unclear if anxiety sensitivity plays a similar role in dissociative identity disorder (DID) where symptoms of depression and PTSD commonly co-occur. We examined the association between anxiety sensitivity, depression, PTSD and dissociative symptoms in DID, hypothesizing a positive association between all symptoms and anxiety sensitivity. METHOD: Participants were 21 treatment-seeking adult females with histories of childhood trauma, current PTSD, and DID. Participants completed the Anxiety Sensitivity Index (ASI), Beck Depression Inventory-II, Childhood Trauma Questionnaire, Multidimensional Inventory of Dissociation, and PTSD Checklist for DSM-5. The ASI included subscales that assessed anxiety sensitivity in cognitive, physical, and social domains. RESULTS: Participants reported high levels of anxiety sensitivity. A multiple regression analysis demonstrated that the ASI cognitive subscale was the strongest predictor of depressive symptoms. No direct associations were identified between anxiety sensitivity and PTSD or dissociative symptoms. We conducted a mediation analysis to test an indirect relationship between cognitive anxiety sensitivity and dissociative symptoms, and found a significant indirect effect through depressive symptoms. CONCLUSIONS: Our results suggest that cognitive anxiety sensitivity or the fear of cognitive dyscontrol is linked with symptom severity in DID. These findings emphasize the need to assess for and utilize interventions that target anxiety sensitivity, which may in turn alleviate symptoms of depression and dissociation in DID.


Asunto(s)
Trastorno Depresivo Mayor , Trastorno Disociativo de Identidad , Trastornos por Estrés Postraumático , Adulto , Ansiedad/psicología , Depresión/diagnóstico , Depresión/psicología , Trastornos Disociativos , Femenino , Humanos , Trastornos por Estrés Postraumático/complicaciones , Trastornos por Estrés Postraumático/psicología
12.
Plants (Basel) ; 11(15)2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35956445

RESUMEN

Wheat leaf rust caused by Puccinia triticina Eriks is an important disease that causes yield losses of up to 40% in susceptible varieties. Tetraploid emmer wheat (T. turgidum ssp. Dicoccum), commonly called Khapli wheat in India, is known to have evolved from wild emmer (Triticum turgidum var. dicoccoides), and harbors a good number of leaf rust resistance genes. In the present study, we are reporting on the screening of one hundred and twenty-three dicoccum wheat germplasm accessions against the leaf rust pathotype 77-5. Among these, an average of 45.50% of the germplasms were resistant, 46.74% were susceptible, and 8.53% had mesothetic reactions. Further, selected germplasm lines with accession numbers IC138898, IC47022, IC535116, IC535133, IC535139, IC551396, and IC534144 showed high level of resistance against the eighteen prevalent pathotypes. The infection type varied from ";", ";N", ";N1" to ";NC". PCR-based analysis of the resistant dicoccum lines with SSR marker gwm508 linked to the Lr53 gene, a leaf rust resistance gene effective against all the prevalent pathotypes of leaf rust in India and identified from a T. turgidum var. dicoccoides germplasm, indicated that Lr53 is not present in the selected accessions. Moreover, we have also generated 35K SNP genotyping data of seven lines and the susceptible control, Mandsaur Local, to study their relationships. The GDIRT tool based on homozygous genotypic differences revealed that the seven genotypes are unique to each other and may carry different resistance genes for leaf rust.

13.
Front Oncol ; 12: 933446, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35992795

RESUMEN

MDM2 and MDM4 proteins are key negative regulators of tumor suppressor p53. MDM2 and MDM4 interact via their RING domains and form a heterodimer polyubiquitin E3 ligase essential for p53 degradation. MDM4 also forms heterodimer E3 ligases with MDM2 isoforms that lack p53-binding domains, which regulate p53 and MDM4 stability. We are working to identify small-molecule inhibitors targeting the RING domain of MDM2-MDM4 (MMRi) that can inactivate the total oncogenic activity of MDM2-MDM4 heterodimers. Here, we describe the identification and characterization of MMRi62 as an MDM4-degrader and apoptosis inducer in leukemia cells. Biochemically, in our experiments, MMRi62 bound to preformed RING domain heterodimers altered the substrate preference toward MDM4 ubiquitination and promoted MDM2-dependent MDM4 degradation in cells. This MDM4-degrader activity of MMRi62 was found to be associated with potent apoptosis induction in leukemia cells. Interestingly, MMRi62 effectively induced apoptosis in p53 mutant, multidrug-resistant leukemia cells and patient samples in addition to p53 wild-type cells. In contrast, MMRi67 as a RING heterodimer disruptor and an enzymatic inhibitor of the MDM2-MDM4 E3 complex lacked MDM4-degrader activity and failed to induce apoptosis in these cells. In summary, this study identifies MMRi62 as a novel MDM2-MDM4-targeting agent and suggests that small molecules capable of promoting MDM4 degradation may be a viable new approach to killing leukemia cells bearing non-functional p53 by apoptosis.

14.
Front Genet ; 13: 834366, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35846116

RESUMEN

Wheat is one of the major staple cereal food crops in India. However, most of the wheat-growing areas experience several biotic and abiotic stresses, resulting in poor quality grains and reduced yield. To ensure food security for the growing population in India, there is a compelling need to explore the untapped genetic diversity available in gene banks for the development of stress-resistant/tolerant cultivars. The improvement of any crop lies in exploring and harnessing the genetic diversity available in its genetic resources in the form of cultivated varieties, landraces, wild relatives, and related genera. A huge collection of wheat genetic resources is conserved in various gene banks across the globe. Molecular and phenotypic characterization followed by documentation of conserved genetic resources is a prerequisite for germplasm utilization in crop improvement. The National Genebank of India has an extensive and diverse collection of wheat germplasm, comprising Indian wheat landraces, primitive cultivars, breeding lines, and collection from other countries. The conserved germplasm can contribute immensely to the development of wheat cultivars with high levels of biotic and abiotic stress tolerance. Breeding wheat varieties that can give high yields under different stress environments has not made much headway due to high genotypes and environmental interaction, non-availability of truly resistant/tolerant germplasm, and non-availability of reliable markers linked with the QTL having a significant impact on resistance/tolerance. The development of new breeding technologies like genomic selection (GS), which takes into account the G × E interaction, will facilitate crop improvement through enhanced climate resilience, by combining biotic and abiotic stress resistance/tolerance and maximizing yield potential. In this review article, we have summarized different constraints being faced by Indian wheat-breeding programs, challenges in addressing biotic and abiotic stresses, and improving quality and nutrition. Efforts have been made to highlight the wealth of Indian wheat genetic resources available in our National Genebank and their evaluation for the identification of trait-specific germplasm. Promising genotypes to develop varieties of important targeted traits and the development of different genomics resources have also been highlighted.

15.
Xenobiotica ; 52(3): 301-311, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35473450

RESUMEN

α-Pinene caused a concentration-responsive increase in bladder hyperplasia and decrease in sperm counts in rodents following inhalation exposure. Additionally, it formed a prospective reactive metabolite, α-pinene oxide.To provide human relevant context for data generated in animal models and explore potential mechanism, we undertook studies to investigate the metabolism of α-pinene to α-pinene oxide and mutagenicity of α-pinene and α-pinene oxide.α-Pinene oxide was formed in rat and human microsomes and hepatocytes with some species differences. Based on area under the concentration versus time curves, the formation of α-pinene oxide was up to 4-fold higher in rats than in humans.While rat microsomes cleared α-pinene oxide faster than human microsomes, the clearance of α-pinene oxide in hepatocytes was similar between species.α-Pinene was not mutagenic with or without induced rat liver S9 in Salmonella typhimurium or Escherichia coli when tested up to 10 000 µg/plate while α-pinene oxide was mutagenic at ≥25 µg/plate.α-Pinene was metabolised to α-pinene oxide under the conditions of the bacterial mutation assay although the concentration was approximately 3-fold lower than the lowest α-pinene oxide concentration that was positive in the assay, potentially explaining the lack of mutagenicity observed with α-pinene.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Atmosféricos/toxicidad , Animales , Monoterpenos Bicíclicos , Daño del ADN , Masculino , Microsomas Hepáticos/metabolismo , Pruebas de Mutagenicidad , Mutágenos/metabolismo , Mutágenos/farmacología , Estudios Prospectivos , Ratas
16.
Front Plant Sci ; 13: 771920, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35283876

RESUMEN

The entire collection of cultivated barley germplasm accessions conserved in the Indian National Genebank (INGB) was characterized for nine qualitative and 8 quantitative traits to assess the nature and magnitude of prevailing genetic variability and to develop a core set. A wide range of variability was observed for days to spike emergence (51-139 days), days to physiological maturity (100-152 days), plant height (45.96-171.32 cm), spike length (3.44-13.73 cm), grain number/spike (10.48-82.35), and 100-grain weight (1.20-6.86 g). Initially, seven independent core sets were derived using 3 core construction tools- MSTRAT, PowerCore, and Core Hunter 3 by employing the maximization method, heuristic sampling, and optimisation of average genetic distances, respectively. The core set-3 generated by Core Hunter 3 by simultaneous optimisation of diversity and representativeness, captured maximum genetic diversity of the whole collection as evident from the desirable genetic distance, variance difference percentage (VD; 87.5%), coincidence rate of range (CR; 94.27%) and variable rate of coefficient of variance (VR; 113.8%), which were more than threshold value of VD (80%), CR (80%), and VR (100%) required for good core collection. The coefficient of variation and Shannon-Weaver diversity indices were increased in the core set as compared with the whole collection. The low value of Kullback-Leibler distance (0.024-0.071) for all traits and quantile-quantile plots revealed a negligible difference between trait distribution patterns among the core set and entire assembly. Correlogram revealed that trait associations and their magnitude were conserved for most of the traits after sampling of the core set. The extraction of the INGB barley core set and identification of promising accessions for agronomically important traits in different genetic backgrounds will pave the way for expedited access to genetically diverse and agronomically important germplasm for barley breeding.

17.
Science ; 376(6588): 59-61, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35357916

RESUMEN

Highlights from the Science family of journals.

18.
Mol Cancer Ther ; 21(4): 535-545, 2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35131878

RESUMEN

High frequency of KRAS and TP53 mutations is a unique genetic feature of pancreatic ductal adenocarcinoma (PDAC). TP53 mutation not only renders PDAC resistance to chemotherapies but also drives PDAC invasiveness. Therapies targeting activating mutant KRAS are not available and the outcomes of current PDAC treatment are extremely poor. Here, we report that MMRi62, initially identified as an MDM2-MDM4-targeting small molecule with p53-independent pro-apoptotic activity, shows anti-PDAC activity in vitro and in vivo. We show that MMRi62 inhibits proliferation, clonogenic, and spheroid growth of PDAC cells by induction of cell death. MMRi62-induced cell death in PDAC is characteristic of ferroptosis that is associated with increased autophagy, increased reactive oxygen species, and lysosomal degradation of NCOA4 and ferritin heavy chain (FTH1). In addition to induced degradation of FTH1, MMRi62 also induces proteasomal degradation of mutant p53. Interestingly, MMRi62-induced ferroptosis occurs in PDAC cell lines harboring either KRAS and TP53 double mutations or single TP53 mutation. In orthotopic xenograft PDAC mouse models, MMRi62 was capable of inhibiting tumor growth in mice associated with downregulation of NCOA4 and mutant p53 in vivo. Strikingly, MMRi62 completely abrogated metastasis of orthotopic tumors to distant organs, which is consistent with MMRi62's ability to inhibit cell migration and invasion in vitro. These findings identified MMRi62 as a novel ferroptosis inducer capable of suppressing PDAC growth and overcoming metastasis.


Asunto(s)
Carcinoma Ductal Pancreático , Ferroptosis , Neoplasias Pancreáticas , Animales , Apoferritinas/uso terapéutico , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Proliferación Celular , Humanos , Ratones , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteína p53 Supresora de Tumor/genética
20.
ACS Catal ; 12(13): 7559-7564, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-36937986

RESUMEN

Saturated heterocycles containing oxygen and sulfur are found in biologically significant molecules. The enantioselective oxysulfenylation of alkenols provides a straightforward synthesis route. To date, organocatalytic methods have dominated this approach. Herein, a complementary approach via copper catalysis is presented. This exoselective method provides enantioenriched arylthiomethyl-substituted tetrahydrofurans, phthalans, isochromans, and morpholines from acyclic alkenols. This method provides the largest scope to date for the exocyclization mode, and with generally high enantioselectivity. The enantioselectivity of this copper-catalyzed oxysulfenylation is rationalized by a proposed mechanism involving alkene oxycupration followed by C─S bond formation via radical-mediated atom transfer.

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