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1.
Opt Express ; 32(8): 13235-13248, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859299

RESUMO

Multi-pass cell (MPC) compressors have proven to be the method of choice for compression of high average power long-pulse Yb lasers. Yet, generating sub-30 fs pulses at high pulse energy with compact and simple components remains a challenge. This work demonstrates an efficient and cost-effective approach for nonlinear pulse compression at high pulse energy using a hybrid air-bulk MPC. By carefully balancing the relative nonlinear contributions of ambient air and fused silica, we achieve strong spectral broadening without dispersion engineering or pressure-control inside the cell at 400-µJ pulse energy. In this way, we compress pulses from 220 fs to 27 fs at 40.3 W of average power (100 kHz repetition rate), enhancing the peak power from 1.6 GW to 10.2 GW while maintaining 78% of the energy within the main pulse. Our approach combines the strengths of gas-filled and bulk compression schemes and exhibits excellent overall optical transmission (91%) and spectral uniformity. Moreover, we utilize the INSIGHT technique to investigate spatio-temporal couplings and geometrical aberrations of the compressed pulse. Our results demonstrate remarkable temporal homogeneity, with an average Strehl ratio of 0.97 consistently observed throughout the entire spectral profile. Additionally, all spectrally-integrated Zernike coefficients for geometrical aberrations maintain values below 0.02λ.

2.
Sci Adv ; 10(20): eadl5904, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758795

RESUMO

Marine heatwaves are increasing in frequency and intensity as climate change progresses, especially in the highly productive Arctic regions. Although their effects on primary producers will largely determine the impacts on ecosystem services, mechanistic understanding on phytoplankton responses to these extreme events is still very limited. We experimentally exposed Arctic phytoplankton assemblages to stable warming, as well as to repeated heatwaves, and measured temporally resolved productivity, physiology, and composition. Our results show that even extreme stable warming increases productivity, while the response to heatwaves depends on the specific scenario applied and is not predictable from stable warming responses. This appears to be largely due to the underestimated impact of the cool phase following a heatwave, which can be at least as important as the warm phase for the overall response. We show that physiological and compositional adjustments to both warm and cool phases drive overall phytoplankton productivity and need to be considered mechanistically to predict overall ecosystem impacts.


Assuntos
Mudança Climática , Ecossistema , Fitoplâncton , Fitoplâncton/fisiologia , Regiões Árticas , Temperatura Alta , Aquecimento Global
3.
J Clin Tuberc Other Mycobact Dis ; 35: 100435, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38601919

RESUMO

Antimicrobial resistance alongside other challenges in tuberculosis (TB) therapeutics have stirred renewed interest in host-directed interventions, including the role of antibodies as adjunct therapeutic agents. This study assessed the binding efficacy of two novel IgG1 opsonic monoclonal antibodies (MABs; GG9 & JG7) at 5, 10, and 25 µg/mL to live cultures of Mycobacterium tuberculosis, M. avium, M. bovis, M. fortuitum, M. intracellulare, and M. smegmatis American Type Culture Collection laboratory reference strains, as well as clinical susceptible, multi-drug resistant, and extensively drug resistant M. tuberculosis strains using indirect enzyme-linked immunosorbent assays. These three MAB concentrations were selected from a range of concentrations used in previous optimization (binding and functional) assays. Both MABs bound to all mycobacterial species and sub-types tested, albeit to varying degrees. Statistically significant differences in MAB binding activity were observed when comparing the highest and lowest MAB concentrations (p < 0.05) for both MABs GG9 and JG7, irrespective of the M. tuberculosis resistance profile. Binding affinity increased with an increase in MAB concentration, and optimal binding was observed at 25 µg/mL. JG7 showed better binding activity than GG9. Both MABs also bound to five MOTT species, albeit at varied levels. This non-selective binding to different mycobacterial species suggests a potential role for GG9 and JG7 as adjunctive agents in anti-TB chemotherapy with the aim to enhance bacterial killing.

4.
Ann Plast Surg ; 92(4): 457-462, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38527353

RESUMO

BACKGROUND: Since their development, integrated plastic and reconstructive surgery (PRS) residency training programs have established diverse methods of incorporating general surgery training into graduate medical education. Programs have questioned the necessary duration and timing of such training. The aim of this study is to assess the landscape of general surgery exposure in integrated PRS residency programs. METHODS: Thirty-six integrated PRS residency programs were included based on the availability of postgraduate year (PGY)-level rotation data. Rotations were measured in units of weeks with descriptive titles maintained as advertised by the program. Individual general surgery rotations were also categorized as being either PRS-aligned, American Board of Plastic Surgery (ABPS) Required Clinical (RC) or ABPS Strongly Suggested (SS). Statistical analyses were carried out on the relative proportions of each subcategory in the 2 parent groups. RESULTS: All 36 programs evaluated required general surgery rotations in years PGY- 1 to -2. By PGY-3, 69% of programs required general surgery, and by PGY-6, 25%, and these were limited to 4- to 6-week rotations in burn, breast, or trauma. Looking across all 6 years, with 312 weeks of training total, the minimum number of weeks spent in general surgery rotations was 32, and the maximum number was 119, with an average of 61 weeks (±21).Programs were subcategorized into 2 groups based on whether they spent more (n = 16) or less (n = 20) than the net average number of weeks in ABPS RC + SS rotations. No significant difference was found in the relative proportion of PRS-aligned general surgery across groups. Programs with <60 weeks of general surgery had a relatively greater proportion of ABPS RC and SS rotations. CONCLUSIONS: These data demonstrate that there exists significant variability in overall duration of general surgery training across integrated PRS training programs. When controlling overall general surgery exposure for variables of interest like PRS-aligned exposure or compatibility with ABPS requirements, we found no discernable educational model or patterns to explain the observed range in exposure. These results warrant reexamination of an ideal general surgery track within the integrated plastic surgery training model that optimizes training for the PRS resident.


Assuntos
Queimaduras , Cirurgia Geral , Internato e Residência , Cirurgia Plástica , Humanos , Estados Unidos , Cirurgia Plástica/educação , Currículo , Educação de Pós-Graduação em Medicina
5.
Opt Lett ; 49(6): 1591-1594, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489458

RESUMO

We report on a GHz fundamental repetition rate Kerr-lens mode-locked Ho:CALGO laser emitting at 2.1 µm. The laser employs a ring cavity to increase the fundamental repetition rate to 1.179 GHz and can be made to oscillate in both directions stably with nearly identical performance: for the counterclockwise oscillation, it generates 93-fs pulses at 1.68 W of average power, whereas 92 fs and 1.69 W were measured for the clockwise operation. Our current results represent the highest average power from a 2-µm GHz oscillator and, to our knowledge, the first sub-100-fs pulse duration from a Ho-based oscillator.

6.
Ophthalmic Plast Reconstr Surg ; 40(4): e142-e145, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38534054

RESUMO

Orbital plasmacytoma is a rare plasma cell tumor that may arise as an aggressive form of extramedullary multiple myeloma. Treatment modalities include surgical excision, radiation, and chemotherapy. Chimeric antigen receptor T cell therapy is currently reserved for refractory disease. The authors present a case of a 69-year-old woman with an extensive orbital plasmacytoma refractory to multimodal therapy who was treated with idecabtagene vicleucel chimeric antigen receptor T cell therapy. Four days after infusion, the patient exhibited grade 1 cytokine release syndrome, which resolved with tocilizumab. The orbital plasmacytoma significantly decreased in size 1 month after treatment and demonstrated complete serological response and sustained tumor burden reduction at 10-month follow-up. This case highlights the efficacy of chimeric antigen receptor T cell therapy for refractory orbital plasmacytoma and calls attention to potential inflammatory toxicities.


Assuntos
Neoplasias Orbitárias , Plasmocitoma , Receptores de Antígenos Quiméricos , Humanos , Idoso , Feminino , Neoplasias Orbitárias/terapia , Plasmocitoma/terapia , Plasmocitoma/diagnóstico , Receptores de Antígenos Quiméricos/uso terapêutico , Imunoterapia Adotiva/métodos
7.
Glob Chang Biol ; 30(1): e17090, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273483

RESUMO

Microalgae are the main source of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), essential for the healthy development of most marine and terrestrial fauna including humans. Inverse correlations of algal EPA and DHA proportions (% of total fatty acids) with temperature have led to suggestions of a warming-induced decline in the global production of these biomolecules and an enhanced importance of high latitude organisms for their provision. The cold Arctic Ocean is a potential hotspot of EPA and DHA production, but consequences of global warming are unknown. Here, we combine a full-seasonal EPA and DHA dataset from the Central Arctic Ocean (CAO), with results from 13 previous field studies and 32 cultured algal strains to examine five potential climate change effects; ice algae loss, community shifts, increase in light, nutrients, and temperature. The algal EPA and DHA proportions were lower in the ice-covered CAO than in warmer peripheral shelf seas, which indicates that the paradigm of an inverse correlation of EPA and DHA proportions with temperature may not hold in the Arctic. We found no systematic differences in the summed EPA and DHA proportions of sea ice versus pelagic algae, and in diatoms versus non-diatoms. Overall, the algal EPA and DHA proportions varied up to four-fold seasonally and 10-fold regionally, pointing to strong light and nutrient limitations in the CAO. Where these limitations ease in a warming Arctic, EPA and DHA proportions are likely to increase alongside increasing primary production, with nutritional benefits for a non-ice-associated food web.


Assuntos
Diatomáceas , Ácidos Graxos Ômega-3 , Humanos , Camada de Gelo , Oceanos e Mares , Regiões Árticas , Ácidos Graxos
8.
Sci Rep ; 14(1): 586, 2024 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-38182631

RESUMO

Mammalian pregnancy requires gradual yet extreme remodeling of the reproductive organs to support the growth of the embryos and their birth. After delivery, the reproductive organs return to their non-pregnant state. As pregnancy has traditionally been understudied, there are many unknowns pertaining to the mechanisms behind this remarkable remodeling and repair process which, when not successful, can lead to pregnancy-related complications such as maternal trauma, pre-term birth, and pelvic floor disorders. This study presents the first longitudinal imaging data that focuses on revealing anatomical alterations of the vagina, cervix, and uterine horns during pregnancy and postpartum using the mouse model. By utilizing advanced magnetic resonance imaging (MRI) technology, T1-weighted and T2-weighted images of the reproductive organs of three mice in their in vivo environment were collected at five time points: non-pregnant, mid-pregnant (gestation day: 9-10), late pregnant (gestation day: 16-17), postpartum (24-72 h after delivery) and three weeks postpartum. Measurements of the vagina, cervix, and uterine horns were taken by analyzing MRI segmentations of these organs. The cross-sectional diameter, length, and volume of the vagina increased in late pregnancy and then returned to non-pregnant values three weeks after delivery. The cross-sectional diameter of the cervix decreased at mid-pregnancy before increasing in late pregnancy. The volume of the cervix peaked at late pregnancy before shortening by 24-72 h postpartum. As expected, the uterus increased in cross-sectional diameter, length, and volume during pregnancy. The uterine horns decreased in size postpartum, ultimately returning to their average non-pregnant size three weeks postpartum. The newly developed methods for acquiring longitudinal in vivo MRI scans of the murine reproductive system can be extended to future studies that evaluate functional and morphological alterations of this system due to pathologies, interventions, and treatments.


Assuntos
Imageamento por Ressonância Magnética , Útero , Feminino , Humanos , Gravidez , Animais , Camundongos , Útero/diagnóstico por imagem , Projetos de Pesquisa , Vagina/diagnóstico por imagem , Período Pós-Parto , Mamíferos
9.
Ecol Lett ; 27(1): e14349, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38178545

RESUMO

The emergence of billions of periodical cicadas affects plant and animal communities profoundly, yet little is known about cicada impacts on soil carbon fluxes. We investigated the effects of Brood X cicadas (Magicicada septendecim, M. cassinii and M. septendeculain) on soil CO2 fluxes (RS ) in three Indiana forests. We hypothesized RS would be sensitive to emergence hole density, with the greatest effects occurring in soils with the lowest ambient fluxes. In support of our hypothesis, RS increased with increasing hole density and greater effects were observed near AM-associating trees (which expressed lower ambient fluxes) than near EcM-associating trees. Additionally, RS from emergence holes increased the temperature sensitivity (Q10 ) of RS by 13%, elevating the Q10 of ecosystem respiration. Brood X cicadas increased annual RS by ca. 2.5%, translating to an additional 717 Gg of CO2 across forested areas. As such, periodical cicadas can have substantial effects on soil processes and biogeochemistry.


Assuntos
Hemípteros , Micorrizas , Animais , Árvores , Ecossistema , Solo , Dióxido de Carbono , Florestas
10.
Med Sci Sports Exerc ; 56(5): 917-926, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38233976

RESUMO

PURPOSE: This study quantified the metabolic demands (oxygen uptake (V̇O 2 )), power output adjustments, changes in the V̇O 2 /power output ratio, and perceptual responses (rating of perceived exertion (RPE)) during constant heart rate (HR) exercise performed within the vigorous intensity range (77%-95% HR peak ). METHODS: Twelve women (mean ± SD age, 22 ± 4 yr) performed a graded exercise test to exhaustion to determine peak parameters, and three randomly ordered, constant HR trials to exhaustion or for 60 min at the lower (HR L = 77% HR peak ), middle (HR M = 86% HR peak ), and higher (HR H = 95% HR peak ) end of the vigorous intensity range. Time course of changes and patterns of responses were examined for V̇O 2 , power output, V̇O 2 /power output, and RPE for the composite and for each subject. RESULTS: Across the HR L (time to exhaustion ( Tlim ) = 56.3 ± 9.9 min), HR M (51.8 ± 13.5 min), and HR H (27.2 ± 17.7 min) trials, V̇O 2 and power output decreased quadratically ( P < 0.05) relative to the initial value from 10% to 100% of Tlim , whereas the V̇O 2 /power output increased quadratically from 20% to 100% Tlim , and RPE increased linearly from 50% to 100% Tlim . The V̇O 2 and RPE, collapsed across time, for HR L (54.3% ± 3.3% V̇O 2peak , 11 ± 1.5 RPE) were lower than HR M (64.9% ± 4.5% V̇O 2peak , 14 ± 1.7 RPE), and both were lower than HR H (80.1% ± 4.1% V̇O 2peak , 17 ± 1.4 RPE). None of the 12 subjects at HR L , 6 at HR M , and 7 at HR H were within the vigorous V̇O 2 range. CONCLUSIONS: The HR L was not sufficient to meet the desired metabolic intensity for vigorous exercise, whereas the middle to higher end of the range elicited a V̇O 2 within the prescribed range of only ~50%-60% of the subjects. This study indicated that exercise held constant at a percentage of HR peak cannot consistently be used to prescribe a desired metabolic stimulus.


Assuntos
Exercício Físico , Consumo de Oxigênio , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Frequência Cardíaca/fisiologia , Consumo de Oxigênio/fisiologia , Exercício Físico/fisiologia , Teste de Esforço , Esforço Físico/fisiologia
11.
Orbit ; 43(1): 41-48, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36880205

RESUMO

PURPOSE: To assess whether transcutaneous retrobulbar amphotericin B injections (TRAMB) reduce exenteration rate without increasing mortality in rhino-orbital-cerebral mucormycosis (ROCM). METHODS: In this retrospective case-control study, 46 patients (51 eyes) with biopsy-proven ROCM were evaluated at 9 tertiary care institutions from 1998 to 2021. Patients were stratified by radiographic evidence of local orbital versus extensive involvement at presentation. Extensive involvement was defined by MRI or CT evidence of abnormal or loss of contrast enhancement of the orbital apex with or without cavernous sinus, bilateral orbital, or intracranial extension. Cases (+TRAMB) received TRAMB as adjunctive therapy while controls (-TRAMB) did not. Patient survival, globe survival, and vision/motility loss were compared between +TRAMB and -TRAMB groups. A generalized linear mixed effects model including demographic and clinical covariates was used to evaluate the impact of TRAMB on orbital exenteration and disease-specific mortality. RESULTS: Among eyes with local orbital involvement, exenteration was significantly lower in the +TRAMB group (1/8) versus -TRAMB (8/14) (p = 0.04). No significant difference in mortality was observed between the ±TRAMB groups. Among eyes with extensive involvement, there was no significant difference in exenteration or mortality rates between the ±TRAMB groups. Across all eyes, the number of TRAMB injections correlated with a statistically significant decreased rate of exenteration (p = 0.048); there was no correlation with mortality. CONCLUSIONS: Patients with ROCM with local orbital involvement treated with adjunctive TRAMB demonstrated a lower exenteration rate and no increased risk of mortality. For extensive involvement, adjunctive TRAMB does not improve or worsen these outcomes.


Assuntos
Oftalmopatias , Mucormicose , Doenças Orbitárias , Humanos , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Mucormicose/diagnóstico por imagem , Mucormicose/tratamento farmacológico , Estudos Retrospectivos , Estudos de Casos e Controles , Doenças Orbitárias/diagnóstico por imagem , Doenças Orbitárias/tratamento farmacológico , Oftalmopatias/tratamento farmacológico
12.
J Phys Chem A ; 127(51): 10789-10796, 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38109666

RESUMO

The resonant Raman (RR) and resonant SERS spectra of the thiadiazole-based dye dibromobenzo[c]-1,2,5-thiadiazole (DBTD) were studied through multiconfigurational XMS-CASPT2/CASSCF and experimental methods in solution. The results indicate that the S1 excited state of DBTD is described by π → π* with internal CT from the benzene ring to the thiadizole. In resonance conditions at 364 nm, the RR spectrum shows intensifications in modes that describe extensive geometrical changes at both the benzene ring and the thiadiazole region, indicating an internal CT character to the S1. The SERS spectra observed on gold and silver nanoparticles indicate different adsorption geometries, which leads to distinct enhancement patterns on the spectra with varying excitation energy. It evidences the major contribution of the chemical enhancement mechanism on the spectra from a metal → DBTD CT state, as confirmed by the simulated spectra. This theoretical approach proved strong in the prediction of the main features of the observed experimental resonant Raman and SERS spectra indicating a potential for adequate description of the chemical mechanism of SERS.

13.
Artigo em Inglês | MEDLINE | ID: mdl-37972960

RESUMO

PURPOSE: Teprotumumab, an insulin-like growth factor 1 receptor monoclonal antibody, is FDA-approved to treat thyroid eye disease (TED). The initial clinical trials excluded patients with previous orbital irradiation, surgery, glucocorticoid use (cumulative dose >1 gm), or prior biologic treatment. Information on the use of teprotumumab for patients who failed prior therapy is limited. Our purpose is to characterize the efficacy of teprotumumab for the treatment of recalcitrant TED. METHODS: This is a multicenter retrospective study of all patients treated with teprotumumab for moderate-to-severe TED after failing conventional therapy with corticosteroids, orbital radiation, surgical decompression, biologics, or other steroid-sparing medications. Treatment failure was defined as an incomplete response to or reactivation after previous treatment. Only patients who received at least 4 infusions of teprotumumab were included in the analysis. Primary outcome measures comprised proptosis response (≥2 mm reduction in the study eye without a similar increase in the other eye), clinical activity score (CAS) response (≥2-point reduction in CAS), and diplopia response (≥1 point improvement in Gorman diplopia score in patients with baseline diplopia) following treatment. Adverse events and risk factors for recalcitrant disease were also evaluated. RESULTS: Sixty-six patients were included in this study, 46 females and 20 males. Average age was 59.3 years (range 29-93). The mean duration of disease from TED diagnosis to first infusion was 57.8 months. The proptosis, CAS, and diplopia responses in this recalcitrant patient population were 85.9%, 93.8%, and 69.1%, respectively. Patients experienced a mean reduction in proptosis of 3.1 ± 2.4 mm and a mean improvement in CAS of 3.8 ± 1.6. Patients who underwent prior decompression surgery experienced a statistically significant decrease in diplopia response (46.7% vs. 77.5%, p = 0.014) and proptosis response (75.0% vs. 90.9%, p = 0.045) when compared with nondecompression patients. Additionally, there were no significant differences in proptosis, CAS, and diplopia responses between patients with acute (defined as disease duration <1 year) versus chronic (disease duration ≥1 year) TED. While most adverse events were mild to moderate, 4 patients reported serious adverse events related to persistent hearing loss. CONCLUSIONS: Patients with recalcitrant TED demonstrated a significant improvement after teprotumumab in each of the primary study outcomes. The degree of proptosis reduction, diplopia response, and CAS improvement in the recalcitrant group were similar to those of treatment-naïve patients from the pivotal clinical trials. Patients with a prior history of orbital decompression, however, demonstrated poor improvement in diplopia and less reduction in proptosis than surgery naïve patients. These results indicate that teprotumumab is a treatment option for the treatment of patients with TED recalcitrant to prior medical therapies.

14.
Innov Aging ; 7(7): igad091, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781066

RESUMO

Background and Objectives: Given the increase in methodological pluralism in research on brain health, cognitive aging, and neurodegenerative diseases, this scoping review aims to provide a descriptive overview and qualitative content analysis of studies stating the use of participatory research approaches within Alzheimer's disease and related dementias (ADRD) literature globally. Research Design and Methods: We conducted a systematic search across four multidisciplinary databases (CINAHL, SCOPUS, PsycInfo, PubMed) for peer-reviewed, English-language studies addressing ADRD that explicitly described their use of a participatory research approach. We employed a systematic process for selecting articles that yielded a final sample of 163 studies. Data from articles were analyzed to chart trends from 1990 to 2022 in terminology, descriptions, application of participatory approaches, and the extent and nature of partnerships with nonacademics. Results: Results demonstrated geographic differences in the use of stated approaches between North America-where community-based participatory research predominates-and Europe, where Action Research is most common. We further found that only 73% of papers in this systematic review had identifiable definitions or descriptions of the participatory approach used. Findings also showed that 14% of articles demonstrated no evidence of engaged partnership beyond activities typical of research participants, while 23% of articles identified partnering with people with dementia, and an additional 16% reported partnerships with members from Indigenous, Black, Asian, or Latinx communities. Discussion and Implications: This scoping review identifies three areas in need of greater attention in ADRD literature using participatory research approaches. First, findings indicate the importance of strengthening the use, transparency, and rigor of participatory methods. Second, results suggest the need for greater inclusion of historically marginalized groups who are most affected by ADRD as research partners. Finally, the findings highlight the need for integrating social justice values of participatory approaches into research project designs.

15.
Genome Biol ; 24(1): 227, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828516

RESUMO

BACKGROUND: In several eukaryotes, DNA methylation occurs within the coding regions of many genes, termed gene body methylation (GbM). Whereas the role of DNA methylation on the silencing of transposons and repetitive DNA is well understood, gene body methylation is not associated with transcriptional repression, and its biological importance remains unclear. RESULTS: We report a newly discovered type of GbM in plants, which is under constitutive addition and removal by dynamic methylation modifiers in all cells, including the germline. Methylation at Dynamic GbM genes is removed by the DRDD demethylation pathway and added by an unknown source of de novo methylation, most likely the maintenance methyltransferase MET1. We show that the Dynamic GbM state is present at homologous genes across divergent lineages spanning over 100 million years, indicating evolutionary conservation. We demonstrate that Dynamic GbM is tightly associated with the presence of a promoter or regulatory chromatin state within the gene body, in contrast to other gene body methylated genes. We find Dynamic GbM is associated with enhanced gene expression plasticity across development and diverse physiological conditions, whereas stably methylated GbM genes exhibit reduced plasticity. Dynamic GbM genes exhibit reduced dynamic range in drdd mutants, indicating a causal link between DNA demethylation and enhanced gene expression plasticity. CONCLUSIONS: We propose a new model for GbM in regulating gene expression plasticity, including a novel type of GbM in which increased gene expression plasticity is associated with the activity of DNA methylation writers and erasers and the enrichment of a regulatory chromatin state.


Assuntos
Metilação de DNA , Plantas , Plantas/genética , Evolução Biológica , Expressão Gênica , Cromatina
16.
Opt Express ; 31(16): 25718-25723, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710451

RESUMO

This Joint Issue of Optics Express and Optical Materials Express features 40 peer-reviewed articles written by authors who participated in the Advanced Solid State Lasers Conference, part of the Optica Laser Congress and Exhibition held in Barcelona, Spain from December 11-15, 2022. This review provides a brief summary of these articles covering the latest developments in laser host and nonlinear crystals, structured materials, fiber lasers and amplifiers, ultrafast mode-locked lasers and optical parametric amplifiers, frequency-doubled Raman lasers, vortex beams, and novel concepts in laser design.

17.
Opt Express ; 31(18): 29480-29490, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37710747

RESUMO

As high-average power ultrafast lasers become increasingly available for nonlinear conversion, the temperature dependence of the material properties of nonlinear crystals becomes increasingly relevant. Here, we present temperature-dependent THz complex refractive index measurements of the organic crystal BNA over a wide range of temperatures from 300 K down to 80 K for THz frequencies up to 4 THz for the first time. Our measurements show that whereas the temperature-dependent refractive index has only minor deviation from room temperature values, the temperature-dependent absorption coefficient decreases at low temperature (-24% from 300 K to 80 K). We additionally compare these measurements with conversion efficiency and spectra observed during THz generation experiments using the same crystal actively cooled in the same temperature range, using an ultrafast Yb-laser for excitation. Surprisingly, the damage threshold of the material does not improve significantly upon active cooling, pointing to a nonlinear absorption mechanism being responsible for damage. However, we observe a significant increase in THz yield (+23%) at lower temperatures, which is most likely due to the reduced THz absorption. These first findings will be useful for future designs of high-average power pumped organic-crystal based THz-TDS systems.

18.
Biochem Biophys Rep ; 35: 101539, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37720314

RESUMO

The CRISPR/Cas9 technology is a revolutionary tool that can be used to edit the genome. Specifically, the genome of hematopoietic stem cells (HSCs) could be edited to correct monogenic blood disorders as well as produce immunotherapies. However, the efficiency of editing HSCs remains low. To overcome this hurdle, we set out to investigate the use of metformin, an FDA-approved drug, to enhance gene modification. We assessed the effect of metformin on the growth of two hematopoietic cell lines: a myeloid-erythroid leukemic cell line (K562 cells) representative of the myeloid population and an immortalized T lymphocyte cell line (Jurkat cells) representative of the lymphoid population. No significant difference in growth patterns was observed in concentrations up to 10 mM metformin in both cell lines. We then assessed the ability of two different concentrations of metformin (0.001 mM or 1 mM), based on our observations, to enhance both (1) the cutting efficiency of Cas9 and (2) the targeting efficiency with the use of a donor DNA repair template. The cutting efficiency of Cas9 was significantly enhanced in a total of five guide RNAs (four specific to a platelet locus and one specific to an erythroid locus) following treatment. In addition, an enhancement in targeting was observed with the use of a GFP-containing donor DNA repair template with both concentrations. Overall, a greater than two-fold increase in GFP expression was noted in cells treated with metformin. This suggests that metformin, an FDA-approved drug, could be added to existing protocols to enhance CRISPR/Cas9 gene editing.

19.
Vaccines (Basel) ; 11(9)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37766144

RESUMO

An unconjugated composite peptide vaccine targeting multiple conserved influenza epitopes from hemagglutinin, neuraminidase, and matrix protein and formulated with a safe and highly potent adjuvant, Army Liposome formulation (ALFQ), generated broad and durable immune responses in outbred mice. The antibodies recognized specific epitopes in influenza peptides and several human, avian, and swine influenza viruses. Comparable antibody responses to influenza viruses were observed with intramuscular and intradermal routes of vaccine administration. The peptide vaccine induced cross-reactive antibodies that recognized influenza virus subtypes A/H1N1, A/H3N2, A/H5N1, B/Victoria, and B/Yamagata. In addition, immune sera neutralized seasonal and pandemic influenza strains (Group 1 and Group 2). This composite multi-epitope peptide vaccine, formulated with ALFQ and administered via intramuscular and intradermal routes, provides a high-performance supra-seasonal vaccine that would be cost-effective and easily scalable, thus moving us closer to a viable strategy for a universal influenza vaccine and pandemic preparedness.

20.
Nat Commun ; 14(1): 4887, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37580358

RESUMO

Atmospheric gaseous elemental mercury (GEM) concentrations in the Arctic exhibit a clear summertime maximum, while the origin of this peak is still a matter of debate in the community. Based on summertime observations during the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition and a modeling approach, we further investigate the sources of atmospheric Hg in the central Arctic. Simulations with a generalized additive model (GAM) show that long-range transport of anthropogenic and terrestrial Hg from lower latitudes is a minor contribution (~2%), and more than 50% of the explained GEM variability is caused by oceanic evasion. A potential source contribution function (PSCF) analysis further shows that oceanic evasion is not significant throughout the ice-covered central Arctic Ocean but mainly occurs in the Marginal Ice Zone (MIZ) due to the specific environmental conditions in that region. Our results suggest that this regional process could be the leading contributor to the observed summertime GEM maximum. In the context of rapid Arctic warming and the observed increase in width of the MIZ, oceanic Hg evasion may become more significant and strengthen the role of the central Arctic Ocean as a summertime source of atmospheric Hg.

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