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1.
Nature ; 609(7926): 265-268, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36071186

RESUMEN

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare4 in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet5, plasma instabilities6,7 or orbital motion in an accretion disc7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. 9). BL Lac, the prototype of a subclass of blazars10, is powered by a 1.7 × 108 MSun (ref. 11) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. 12)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities6 near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.

2.
Phys Rev Lett ; 132(9): 096502, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38489610

RESUMEN

Low-disorder two-dimensional electron systems in the presence of a strong, perpendicular magnetic field terminate at very small Landau level filling factors in a Wigner crystal (WC), where the electrons form an ordered array to minimize the Coulomb repulsion. The nature of this exotic, many-body, quantum phase is yet to be fully understood and experimentally revealed. Here we probe one of WC's most fundamental parameters, namely, the energy gap that determines its low-temperature conductivity, in record mobility, ultrahigh-purity, two-dimensional electrons confined to GaAs quantum wells. The WC domains in these samples contain ≃1000 electrons. The measured gaps are a factor of three larger than previously reported for lower quality samples, and agree remarkably well with values predicted for the lowest-energy, intrinsic, hypercorrelated bubble defects in a WC made of flux-electron composite fermions, rather than bare electrons. The agreement is particularly noteworthy, given that the calculations are done for disorder-free composite fermion WCs, and there are no adjustable parameters. The results reflect the exceptionally high quality of the samples, and suggest that composite fermion WCs are indeed more stable compared to their electron counterparts.

3.
Nature ; 558(7710): 406-409, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29925969

RESUMEN

It has been known for decades that the observed number of baryons in the local Universe falls about 30-40 per cent short1,2 of the total number of baryons predicted 3 by Big Bang nucleosynthesis, as inferred4,5 from density fluctuations of the cosmic microwave background and seen during the first 2-3 billion years of the Universe in the so-called 'Lyman α forest'6,7 (a dense series of intervening H I Lyman α absorption lines in the optical spectra of background quasars). A theoretical solution to this paradox locates the missing baryons in the hot and tenuous filamentary gas between galaxies, known as the warm-hot intergalactic medium. However, it is difficult to detect them there because the largest by far constituent of this gas-hydrogen-is mostly ionized and therefore almost invisible in far-ultraviolet spectra with typical signal-to-noise ratios8,9. Indeed, despite large observational efforts, only a few marginal claims of detection have been made so far2,10. Here we report observations of two absorbers of highly ionized oxygen (O VII) in the high-signal-to-noise-ratio X-ray spectrum of a quasar at a redshift higher than 0.4. These absorbers show no variability over a two-year timescale and have no associated cold absorption, making the assumption that they originate from the quasar's intrinsic outflow or the host galaxy's interstellar medium implausible. The O VII systems lie in regions characterized by large (four times larger than average 11 ) galaxy overdensities and their number (down to the sensitivity threshold of our data) agrees well with numerical simulation predictions for the long-sought warm-hot intergalactic medium. We conclude that the missing baryons have been found.

4.
Nutr Neurosci ; : 1-19, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287652

RESUMEN

Many epidemiological studies have shown the beneficial effects of a largely plant-based diet, and the strong association between the consumption of a Mediterranean-type diet with healthy aging including a lower risk of cognitive decline. The Mediterranean diet is characterized by a high intake of olive oil, fruits and vegetables and is rich in dietary fiber and polyphenols - both of which have been postulated to act as important mediators of these benefits. Polyphenols are large molecules produced by plants to protect them from environmental threats and injury. When ingested by humans, as little as 5% of these molecules are absorbed in the small intestine with the majority metabolized by the gut microbiota into absorbable simple phenolic compounds. Flavan-3-ols, a type of flavonoid, contained in grapes, berries, pome fruits, tea, and cocoa have been associated with many beneficial effects on several risk factors for cardiovascular disease, cognitive function and brain regions involved in memory formation. Both preclinical and clinical studies suggest that these brain and heart benefits can be attributed to endothelial vascular effects and anti-inflammatory properties among others. More recently the gut microbiota has emerged as a potential modulator of the aging brain and intriguingly polyphenols have been shown to alter microbiota composition and be metabolized by different microbial species. However, there is a need for well controlled studies in large populations to identify predictors of response, particularly given the vast inter-individual variation of human gut microbiota.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38828497

RESUMEN

BACKGROUND: General anaesthesia is standard of care for patients undergoing robot assisted laparoscopic prostatectomy (RALP). However, postoperative pain and bladder discomfort remains an issue, and optimising pain management could improve recovery and promote earlier home discharge. The main objective of this trial was to evaluate if patients receiving spinal anaesthesia are more frequently home ready at 8 pm on the same day compared with multimodal pain management following RALP under general anaesthesia. METHODS: This pragmatic, randomised controlled, multicentre trial was performed between January 2019 to December 2021. Patients undergoing RALP under general anaesthesia were randomised to either multimodal analgesia using parecoxib and morphine intra-operatively (Group GM) or spinal anaesthesia with bupivacaine and sufentanil (Group GS). The primary aim, home readiness, was assessed using a post-anaesthesia discharge scoring system. RESULTS: Of 202 patients analysed, 27% patients reached home readiness criteria after 12 h, 46% after 24 h and 79% after 48 h, without differences between the groups. Urge to pass urine was greater in group GM than in group GS (p ⟨0.001) and lasted for a median of two hours in both groups. More patients expressed satisfaction with postoperative care in group GS (p ⟨0.001). No other significant differences were found between the groups. DISCUSSION: We found no difference in time to home readiness between the groups. Approximately one-fourth of the patients achieved home readiness the same day after surgery without difference between the groups. Fewer patients had urge, and patient satisfaction was greater in group GS.

6.
Occup Med (Lond) ; 74(1): 45-52, 2024 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-37040624

RESUMEN

BACKGROUND: There may be differential impact of the COVID-19 pandemic on mental health and burnout rates of healthcare professionals (HCPs) performing different roles. AIMS: To examine mental health and burnout rates, and possible drivers for any disparities between professional roles. METHODS: In this cohort study, online surveys were distributed to HCPs in July-September 2020 (baseline) and re-sent 4 months later (follow-up; December 2020) assessing for probable major depressive disorder (MDD), generalized anxiety disorder (GAD), insomnia, mental well-being and burnout (emotional exhaustion and depersonalization). Separate logistic regression models (at both phases) compared the risk of outcomes between roles: healthcare assistants (HCAs), nurses and midwives (nurses), allied health professionals (AHPs) and doctors (reference group). Separate linear regression models were also developed relating the change in scores to professional role. RESULTS: At baseline (n = 1537), nurses had a 1.9-fold and 2.5-fold increased risk of MDD and insomnia, respectively. AHPs had a 1.7-fold and 1.4-fold increased risk of MDD and emotional exhaustion, respectively. At follow-up (n = 736), the disproportionate risk between doctors and others worsened: nurses and HCAs were at 3.7-fold and 3.6-fold increased risk of insomnia, respectively. Nurses also had a significantly increased risk of MDD, GAD, poor mental well-being and burnout. Nurses also had significantly worsened anxiety, mental well-being and burnout scores over time, relative to doctors. CONCLUSIONS: Nurses and AHPs had excess risk of adverse mental health and burnout during the pandemic, and this difference worsened over time (in nurses especially). Our findings support adoption of targeted strategies accounting for different HCP roles.


Asunto(s)
Agotamiento Profesional , COVID-19 , Trastorno Depresivo Mayor , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , COVID-19/epidemiología , COVID-19/complicaciones , Salud Mental , Pandemias , Estudios de Cohortes , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones , Agotamiento Profesional/epidemiología , Agotamiento Profesional/etiología , Agotamiento Profesional/psicología , Encuestas y Cuestionarios
7.
Phys Rev Lett ; 131(5): 056302, 2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37595236

RESUMEN

The even-denominator fractional quantum Hall states (FQHSs) in half-filled Landau levels are generally believed to host non-Abelian quasiparticles and be of potential use in topological quantum computing. Of particular interest is the competition and interplay between the even-denominator FQHSs and other ground states, such as anisotropic phases and composite fermion Fermi seas. Here, we report the observation of an even-denominator fractional quantum Hall state with highly anisotropic in-plane transport coefficients at Landau level filling factor ν=3/2. We observe this state in an ultra-high-quality GaAs two-dimensional hole system when a large in-plane magnetic field is applied. By increasing the in-plane field, we observe a sharp transition from an isotropic composite fermion Fermi sea to an anisotropic even-denominator FQHS. Our data and calculations suggest that a unique feature of two-dimensional holes, namely the coupling between heavy-hole and light-hole states, combines different orbital components in the wave function of one Landau level, and leads to the emergence of a highly anisotropic even-denominator fractional quantum Hall state. Our results demonstrate that the GaAs two-dimensional hole system is a unique platform for the exploration of exotic, many-body ground states.

8.
Phys Rev Lett ; 131(26): 266502, 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-38215363

RESUMEN

Single-component fractional quantum Hall states (FQHSs) at even-denominator filling factors may host non-Abelian quasiparticles that are considered to be building blocks of topological quantum computers. Such states, however, are rarely observed in the lowest-energy Landau level, namely at filling factors ν<1. Here, we report evidence for an even-denominator FQHS at ν=1/4 in ultra-high-quality two-dimensional hole systems confined to modulation-doped GaAs quantum wells. We observe a deep minimum in the longitudinal resistance at ν=1/4, superimposed on a highly insulating background, suggesting a close competition between the ν=1/4 FQHS and the magnetic-field-induced, pinned Wigner solid states. Our experimental observations are consistent with the very recent theoretical calculations that predict that substantial Landau level mixing, caused by the large hole effective mass, can induce composite fermion pairing and lead to a non-Abelian FQHS at ν=1/4. Our results demonstrate that Landau level mixing can provide a very potent means for tuning the interaction between composite fermions and creating new non-Abelian FQHSs.

9.
Phys Rev Lett ; 130(12): 126301, 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-37027870

RESUMEN

Fractional quantum Hall states (FQHSs) at even-denominator Landau level filling factors (ν) are of prime interest as they are predicted to host exotic, topological states of matter. We report here the observation of a FQHS at ν=1/2 in a two-dimensional electron system of exceptionally high quality, confined to a wide AlAs quantum well, where the electrons can occupy multiple conduction-band valleys with an anisotropic effective mass. The anisotropy and multivalley degree of freedom offer an unprecedented tunability of the ν=1/2 FQHS as we can control both the valley occupancy via the application of in-plane strain, and the ratio between the strengths of the short- and long-range Coulomb interaction by tilting the sample in the magnetic field to change the electron charge distribution. Thanks to this tunability, we observe phase transitions from a compressible Fermi liquid to an incompressible FQHS and then to an insulating phase as a function of tilt angle. We find that this evolution and the energy gap of the ν=1/2 FQHS depend strongly on valley occupancy.

10.
Antonie Van Leeuwenhoek ; 116(4): 303-326, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36683073

RESUMEN

Plants are continuously challenged by different pathogenic microbes that reduce the quality and quantity of produce and therefore pose a serious threat to food security. Among them bacterial pathogens are known to cause disease outbreaks with devastating economic losses in temperate, tropical and subtropical regions throughout the world. Bacteria are structurally simple prokaryotic microorganisms and are diverse from a metabolic standpoint. Bacterial infection process mainly involves successful attachment or penetration by using extracellular enzymes, type secretion systems, toxins, growth regulators and by exploiting different molecules that modulate plant defence resulting in successful colonization. Theses bacterial pathogens are extremely difficult to control as they develop resistance to antibiotics. Therefore, attempts are made to search for innovative methods of disease management by the targeting bacterial virulence and manipulating the genes in host plants by exploiting genome editing methods. Here, we review the recent developments in bacterial disease management including the bioactive antimicrobial compounds, bacteriophage therapy, quorum-quenching mediated control, nanoparticles and CRISPR/Cas based genome editing techniques for bacterial disease management. Future research should focus on implementation of smart delivery systems and consumer acceptance of these innovative methods for sustainable disease management.


Asunto(s)
Infecciones Bacterianas , Plantas , Plantas/microbiología , Edición Génica/métodos , Bacterias/genética , Antibacterianos
11.
Clin Radiol ; 78(5): 315-322, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36804271

RESUMEN

Minimally invasive interventional techniques are being utilised more frequently in the management of acute and chronic pulmonary emboli; however, robust clinical evidence is only emerging for the utilisation of these techniques. Hence, there is a need for a robust mechanism of patient selection and careful consideration of the benefits and risks of the interventions. In this review, we discuss the risk stratification mechanisms; the role of the multidisciplinary pulmonary embolism response team to support decision-making; and describe the various commonly used interventional techniques and how these can be integrated into treatment strategies for the benefit of our patients.


Asunto(s)
Embolia Pulmonar , Terapia Trombolítica , Humanos , Terapia Trombolítica/métodos , Embolia Pulmonar/diagnóstico por imagen , Embolia Pulmonar/cirugía , Selección de Paciente
12.
Med Oral Patol Oral Cir Bucal ; 28(2): e99-e107, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36806020

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19) in the recent times have instilled signs of immunosuppression globally which has further precipitated increasing range of opportunistic infections. Mucormycosis is a distressing opportunistic fungal infection with a high incidence and is the third commonest acute invasive infection following candidiasis and aspergillosis. The aim of the present observational study is to delineate the enigmatic histopathological profile between mucormycosis cases seen prior to pandemic (PPM) and pandemic associated mucormycosis (PAM). MATERIAL AND METHODS: Tissue archives of 105 histopathologically diagnosed cases of mucormycosis were included and analysed for demographical details and histopathological parameters like fungal load and localization, granuloma formation, necrosis, inflammatory infiltrate and tissue invasion. RESULTS: 0ut of 105 included cases, 11/105 (10.48%) were reported PPM and 94/105 (89.52%) PAM. Among 94 cases of PAM, 51/94 (54%) cases also showed COVID-19 positivity, while 43/94 (46%) did not. Of all the histological variables, increased fungal load and necrosis were observed in PAM relative to PPM cases. CONCLUSIONS: The histopathological variables like fungal load, necrosis, granuloma formation and tissue invasion, could help the clinician in assessing the clinical status at the time of tissue diagnosis and improve the treatment accordingly.


Asunto(s)
COVID-19 , Mucormicosis , Humanos , Mucormicosis/diagnóstico , Mucormicosis/tratamiento farmacológico , Mucormicosis/epidemiología , Pandemias , COVID-19/epidemiología , Necrosis/complicaciones , Necrosis/epidemiología , Granuloma
13.
Ann Pharm Fr ; 81(2): 315-333, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36037930

RESUMEN

Oral delivery of paliperidone palmitate (PPD), a potent antipsychotic agent, has been reported with a potential risk of very serious drug-induced adverse events such as tachycardia, hyperprolactinemia, sexual dysfunction, and neutropenia. Alternatively, the potential of nasal delivery has also been explored to treat CNS complications by delivering the medicines directly to the brain bypassing the blood-brain barrier. Hence, the objectives of current work were to formulate, design, optimize, and investigate the therapeutic potency of PPD-loaded intranasal in-situ gel (PPGISG) in the treatment of schizophrenia. PPD-nanoemulsion (PNE) was fabricated using water titration technique, was further optimized via Box-Behnken design. Furthermore, the optimized PNE was evaluated for parameters such as globule size, polydispersity index, zeta potential, and % entrapment efficiency were found to be 21.44±1.58nm, 0.268±0.02, -25.56±1.6mV, and 99.89±0.25%, respectively. PNE was further converted to PPGISG utilizing two polymers, poloxamer, and guar gum. Simultaneously, ex-vivo permeation for PNE, PPGISG, and PPD-suspension was found to be 211.40±4.8, 297.89±3.9 and 98.66±1.6µg/cm2, respectively. While PPGISG nanoparticles showed 1.58 and 5.65-folds more Jss than PNE and PPD-suspension. Behavioral studies confirmed that no extrapyramidal symptoms were observed in experimental animals post intranasal administration. Finally, the outcomes of the in-vivo hemato-compatibility study proved that intranasal formulation did not cause any alteration in leukocytes, RBCs, and neutrophils count. Therefore, intranasal delivery of PPGISG can be considered a novel tool for the safe delivery of PPD in schizophrenic patients.


Asunto(s)
Nanopartículas , Poloxámero , Ratas , Animales , Palmitato de Paliperidona , Portadores de Fármacos , Nanogeles , Encéfalo , Sistemas de Liberación de Medicamentos/métodos , Tamaño de la Partícula
14.
Ann Oncol ; 33(8): 824-835, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35533926

RESUMEN

BACKGROUND: 'Stable disease (SD)' as per RECIST is a common but ambiguous outcome in patients receiving immune checkpoint inhibitors (ICIs). This study aimed to characterize SD and identify the subset of patients with SD who are benefiting from treatment. Understanding SD would facilitate drug development and improve precision in correlative research. PATIENTS AND METHODS: A systematic review was carried out to characterize SD in ICI trials. SD and objective response were compared to proliferation index using The Cancer Genome Atlas gene expression data. To identify a subgroup of SD with outcomes mirroring responders, we examined a discovery cohort of non-small-cell lung cancer (NSCLC). Serial cutpoints of two variables, % best overall response and progression-free survival (PFS), were tested to define a subgroup of patients with SD with similar survival as responders. Results were then tested in external validation cohorts. RESULTS: Among trials of ICIs (59 studies, 14 280 patients), SD ranged from 16% to 42% in different tumor types and was associated with disease-specific proliferation index (ρ = -0.75, P = 0.03), a proxy of tumor kinetics, rather than relative response to ICIs. In a discovery cohort of NSCLC [1220 patients, 313 (26%) with SD to ICIs], PFS ranged widely in SD (0.2-49 months, median 4.9 months). The subset with PFS >6 months and no tumor growth mirrored partial response (PR) minor (overall survival hazard ratio 1.0) and was proposed as the definition of SD responder. This definition was confirmed in two validation cohorts from trials of NSCLC treated with durvalumab and found to apply in tumor types treated with immunotherapy in which depth and duration of benefit were correlated. CONCLUSIONS: RECIST-defined SD to immunotherapy is common, heterogeneous, and may largely reflect tumor growth rate rather than ICI response. In patients with NSCLC and SD to ICIs, PFS >6 months and no tumor growth may be considered 'SD responders'. This definition may improve the efficiency of and insight derivable from clinical and translational research.


Asunto(s)
Antineoplásicos Inmunológicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Antineoplásicos Inmunológicos/farmacología , Antineoplásicos Inmunológicos/uso terapéutico , Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología
15.
Ann Surg Oncol ; 29(5): 2773-2783, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35211857

RESUMEN

BACKGROUND: The purpose of this article is to summarize the opinions of the surgical oncology leaders from the Global Forum of Cancer Surgeons (GFCS) about the global impact of COVID-19 pandemic on cancer surgery. METHODS: A panel session (virtual) was held at the annual Society of Surgical Oncology 2021 International Conference on Surgical Cancer Care to address the impact of COVID-19 on cancer surgery globally. Following the virtual meeting, a questionnaire was sent to all the leaders to gather additional opinions. The input obtained from all the leaders was collated and analyzed to understand how cancer surgeons from across the world adapted in real-time to the impact of COVID-19 pandemic. RESULTS: The surgical oncology leaders noted that the COVID-19 pandemic led to severe disruptions in surgical cancer care across all domains of clinical care, education, and research. Several new changes/protocols associated with increased costs were implemented to deliver safe care. Leaders also noted that preexisting disparities in care were exacerbated, and the pandemic had a detrimental effect on well-being and financial status. CONCLUSIONS: The COVID-19 pandemic has led to severe disruptions in surgical cancer care globally. Leaders of the GFCS opined that new strategies need to be implemented to prepare for any future catastrophic events based on the lessons learned from the current events. The GFCS will embark on developing such a roadmap to ensure that surgical cancer care is preserved in the future regardless of any catastrophic global events.


Asunto(s)
COVID-19 , Neoplasias , Cirujanos , Oncología Quirúrgica , COVID-19/epidemiología , Humanos , Neoplasias/cirugía , Pandemias
16.
Phys Rev Lett ; 129(15): 156801, 2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36269975

RESUMEN

Fractional quantum Hall states (FQHSs) exemplify exotic phases of low-disorder two-dimensional (2D) electron systems when electron-electron interaction dominates over the thermal and kinetic energies. Particularly intriguing among the FQHSs are those observed at even-denominator Landau level filling factors, as their quasiparticles are generally believed to obey non-Abelian statistics and be of potential use in topological quantum computing. Such states, however, are very rare and fragile, and are typically observed in the excited Landau level of 2D electron systems with the lowest amount of disorder. Here we report the observation of a new and unexpected even-denominator FQHS at filling factor ν=3/4 in a GaAs 2D hole system with an exceptionally high quality (mobility). Our magnetotransport measurements reveal a strong minimum in the longitudinal resistance at ν=3/4, accompanied by a developing Hall plateau centered at (h/e^{2})/(3/4). This even-denominator FQHS is very unusual as it is observed in the lowest Landau level and in a 2D hole system. While its origin is unclear, it is likely a non-Abelian state, emerging from the residual interaction between composite fermions.

17.
J Nucl Cardiol ; 29(3): 1234-1244, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-33398793

RESUMEN

BACKGROUND: Myocardial blood flow (MBF) can be quantified using dynamic PET studies. These studies also inherently contain tomographic images of early bolus displacement, which can provide cardiopulmonary transit times (CPTT) as measure of cardiopulmonary physiology. The aim of this study was to assess the incremental prognostic value of CPTT in heart transplant (OHT) recipients. METHODS: 94 patients (age 56 ± 16 years, 78% male) undergoing dynamic 13N-ammonia stress/rest studies were included, of which 68 underwent right-heart catherization. A recently validated cardiac allograft vasculopathy (CAV) score based on PET measures of regional perfusion, peak MBF and left-ventricular (LV) ejection fraction (LVEF) was used to identify patients with no, mild or moderate-severe CAV. Time-activity curves of the LV and right ventricular (RV) cavities were obtained and used to calculate the difference between the LV and RV bolus midpoint times, which represents the CPTT and is expressed in heartbeats. Patients were followed for a median of 2.5 years for the occurrence of major adverse cardiac events (MACE), including cardiovascular death, hospitalization for heart failure or acute coronary syndrome, or re-transplantation. RESULTS: CPTT was significantly correlated with cardiac filling pressures (r = .434, P = .0002 and r = .439, P = .0002 for right atrial and pulmonary wedge pressure), cardiac output (r = - .315, P = .01) and LVEF (r = - .513, P < .0001). CPTT was prolonged in patients with MACE (19.4 ± 6.0 vs 14.5 ± 3.0 heartbeats, P < .001, N = 15) with CPTT ≥ 17.75 beats showing optimal discriminatory value in ROC analysis. CPTT ≥ 17.75 heartbeats was associated with a 10.1-fold increased risk (P < .001) of MACE and a 7.3-fold increased risk (P < .001) after adjusting for PET-CAV, age, sex and time since transplant. CONCLUSION: Measurements of cardiopulmonary transit time provide incremental risk stratification in OHT recipients and enhance the value of multiparametric dynamic PET imaging, particularly in identifying high-risk patients.


Asunto(s)
Trasplante de Corazón , Adulto , Anciano , Biomarcadores , Femenino , Atrios Cardíacos , Trasplante de Corazón/efectos adversos , Trasplante de Corazón/métodos , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Medición de Riesgo
18.
Mol Biol Rep ; 49(6): 5535-5545, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35411480

RESUMEN

BACKGROUND: The cytoplasmic-genic male-sterility system has been extensively employed for the production of onion hybrids. Molecular marker-assisted characterization of the cytotypes and genotyping at the restorer-of male-fertility (Ms) locus is important for the accelerated breeding of onion hybrids. Indian onion breeding has focussed more on open-pollinated varieties than hybrids. To accelerate the breeding efforts, marker-assisted selection (MAS) plays a pivotal role. METHODS AND RESULTS: This study aimed to characterize the Indian breeding lines, varieties, hybrids, and exotic accessions for cytotype and Ms locus. For cytoplasm, cytotype markers, accD, and MKFR and for Ms locus identification, PCR markers AcPMS1 and AcSKP1 were employed. Bulk strategy to identify cytoplasm and Ms locus was tested. Sequencing of PCR products amplified by accD was also tried. Both the accD and MKFR were synonymous in cytoplasm identification except in T821 where T cytoplasm was identified. AcPMS1 was more reliable than AcSKP1 for Ms locus identification. Sequencing proved that N and T cytoplasm are identical. Bulking strategy can be used for cytotype identification but not for Ms locus. CONCLUSIONS: Indian onions have a predominance of normal (N) cytoplasm and homozygous recessive (msms) locus. This might be beneficial for hybrid development. S cytoplasm was identified in exotic varieties. For the first time, T cytoplasm has been reported from India. These findings will assist Indian onion breeders to develop MAS strategies for accelerating hybrid development programs. And for the release of onion hybrids with high productivity and uniformity.


Asunto(s)
Infertilidad Masculina , Cebollas , Citoplasma/genética , Humanos , India , Masculino , Fitomejoramiento
19.
Transfus Apher Sci ; 61(5): 103442, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35450806

RESUMEN

OBJECTIVE: Transfusion transmitted infection (TTI) is a major hazard for blood transfusion. The present retrospective chart review was undertaken to study the demographic profile and TTI trends among blood donors to see impact of interventions on blood safety. METHODS: Data of donors and TTI screening results from 2010 to 2019 were analyzed. Degree of significance was determined by Chi square test. RESULTS: Out of 1,68,570 donors, 33,227 (19.7%) were voluntary and 1,35,343 (80.3%) were replacement with 2.8% females and 54% belonging to the age group 18-29 years. Voluntary donation increased by only 3% in ten years and total reactivity rate was 1.6%. The reactive rate for all infections was 0.8% in volunteer donors and 1.95% in replacement donors (p-value < 0.001). The prevalence of HBsAg, HCV, HIV and syphilis showed a significant decline from 2010 to 2014. Of the donors who were reactive for HBV, 8.7% were missed by ELISA but detected by NAT. Donor reactivity for malaria remained the same in this period. CONCLUSION: Newer strategies and effort to increase voluntary donation helping the general public adopt a healthy lifestyle is urgently needed in India. Higher prevalence of TTI among replacement donors is substantiated by this study. Role of counseling of donors cannot be overemphasized. Utility of malaria screening for blood donors needs to be reexamined by evaluating evidences from other blood banks. A rational policy approach, based on a careful assessment of epidemiological data, cost effectiveness analysis, and opinion of stakeholders is necessary for universal adoption of NAT.


Asunto(s)
Infecciones por VIH , Malaria , Reacción a la Transfusión , Femenino , Humanos , Adolescente , Adulto Joven , Adulto , Masculino , Donantes de Sangre , Antígenos de Superficie de la Hepatitis B , Estudios Retrospectivos , Estudios Seroepidemiológicos , Infecciones por VIH/epidemiología , India/epidemiología , Reacción a la Transfusión/epidemiología , Biomarcadores
20.
Clin Radiol ; 77(5): 360-367, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35289293

RESUMEN

AIM: To identify sonographic signs of cholecystitis that correlate with surgical outcomes. MATERIALS AND METHODS: Three hundred and thirty-three consecutive patients who underwent cholecystectomy between 22/06/2014 and 1/3/2016 and underwent abdominal ultrasound (US) within 7 days of surgery were included. Individual US signs, including gallstones, gallbladder distention, wall thickening, pericholecystic fluid, and abscess, were graded by two radiologists, 1 and 2. Outcomes included operative duration (OD), drain placement, partial cholecystectomy, conversion from laparoscopic to open cholecystectomy, surgical pathology, bile leak, infection, and 30-day readmission. US signs and outcomes were analysed using analysis of variance, chi-square test, or odds ratios (OR). RESULTS: Radiologist 1 reported 141/333 and radiologist 2 reported 128/333 patients showed gallbladder distention. For the subset with OD, radiologist 1 reported 140/320 and radiologist 2 reported 126/320 patients showed gallbladder distention. Distention was predictive of increased OD (radiologist 1, +23.2 minutes, p<0.0001; radiologist 2, +19.4 minutes, p=0.0003). Cases with gallbladder distention were more likely to have surgical drain placement (OR= 2.60; 95% confidence interval [CI]: 1.12-6.08, p=0.027 radiologist 1; OR=2.59; 95% CI: 1.13-5.95, p=0.025 radiologist 2). Wall thickening was present in 126/333 patients reported by radiologist 1 and 120/333 by radiologist 2. Cases with wall thickening were more likely to have drain placement (OR=2.66; 95% CI: 1.16-6.13, p=0.021 radiologist 1; OR=3.49; 95% CI: 1.49-8.16, p=0.004 radiologist 2). For the subset with OD, wall thickening was present for 121/320 reported by radiologist 1 and 116/320 by radiologist 2 and predicted longer OD (radiologist 1, +15.9 minutes, p=0.0033; radiologist 2, +13.3 minutes, p=0.0143). CONCLUSION: Gallbladder distention and wall thickening on US correlate with prolonged OD and surgical drain placement in patients with cholecystitis.


Asunto(s)
Colecistectomía Laparoscópica , Colecistitis , Colecistectomía , Colecistitis/diagnóstico por imagen , Colecistitis/patología , Colecistitis/cirugía , Vesícula Biliar/diagnóstico por imagen , Vesícula Biliar/cirugía , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
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