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1.
Annu Rev Med ; 75: 391-399, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-37729030

RESUMO

Hospital at Home (HaH) provides hospital-level services in the home to eligible patients who would otherwise require facility-based hospitalization. In the last two decades, studies have shown that HaH can improve patient outcomes and satisfaction and reduce hospital readmissions. Improved technology and greater experience with the model have led to expansion in the scope of patients served and services provided by the model, but dissemination in the United States has been hampered by lack of insurance coverage until recently. HaH is likely at the tipping point for wide adoption in the United States. To realize its full benefits, HaH will need to continue volume expansion to achieve culture change in clinical practice as facilitated by increased insurance coverage, technological advancements, and improved workforce expertise. It is also essential that HaH programs maintain high-quality acute hospital care, ensure that their benefits can be accessed by hard-to-reach rural populations, and continue to advance health equity.


Assuntos
Hospitalização , Readmissão do Paciente , Humanos , Estados Unidos , Hospitais
2.
Proc Natl Acad Sci U S A ; 120(9): e2216421120, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36802432

RESUMO

Arteriolar smooth muscle cells (SMCs) and capillary pericytes dynamically regulate blood flow in the central nervous system in the face of fluctuating perfusion pressures. Pressure-induced depolarization and Ca2+ elevation provide a mechanism for regulation of SMC contraction, but whether pericytes participate in pressure-induced changes in blood flow remains unknown. Here, utilizing a pressurized whole-retina preparation, we found that increases in intraluminal pressure in the physiological range induce contraction of both dynamically contractile pericytes in the arteriole-proximate transition zone and distal pericytes of the capillary bed. We found that the contractile response to pressure elevation was slower in distal pericytes than in transition zone pericytes and arteriolar SMCs. Pressure-evoked elevation of cytosolic Ca2+ and contractile responses in SMCs were dependent on voltage-dependent Ca2+ channel (VDCC) activity. In contrast, Ca2+ elevation and contractile responses were partially dependent on VDCC activity in transition zone pericytes and independent of VDCC activity in distal pericytes. In both transition zone and distal pericytes, membrane potential at low inlet pressure (20 mmHg) was approximately -40 mV and was depolarized to approximately -30 mV by an increase in pressure to 80 mmHg. The magnitude of whole-cell VDCC currents in freshly isolated pericytes was approximately half that measured in isolated SMCs. Collectively, these results indicate a loss of VDCC involvement in pressure-induced constriction along the arteriole-capillary continuum. They further suggest that alternative mechanisms and kinetics of Ca2+ elevation, contractility, and blood flow regulation exist in central nervous system capillary networks, distinguishing them from neighboring arterioles.


Assuntos
Cálcio , Pericitos , Pericitos/metabolismo , Cálcio/metabolismo , Canais de Cálcio Tipo L , Arteríolas/fisiologia , Sistema Nervoso Central/metabolismo , Cálcio da Dieta
3.
Proc Natl Acad Sci U S A ; 120(44): e2306177120, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37871210

RESUMO

Lepidopterans affect crop production worldwide. The use of transgenes encoding insecticidal proteins from Bacillus thuringiensis (Bt) in crop plants is a well-established technology that enhances protection against lepidopteran larvae. Concern about widespread field-evolved resistance to Bt proteins has highlighted an urgent need for new insecticidal proteins with different modes or sites of action. We discovered a new family of insecticidal proteins from ferns. The prototype protein from Pteris species (Order Polypodiales) and variants from two other orders of ferns, Schizaeales and Ophioglossales, were effective against important lepidopteran pests of maize and soybean in diet-based assays. Transgenic maize and soybean plants producing these proteins were more resistant to insect damage than controls. We report here the crystal structure of a variant of the prototype protein to 1.98 Å resolution. Remarkably, despite being derived from plants, the structure resembles the 3-domain Cry proteins from Bt but has only two out of three of their characteristic domains, lacking the C-terminal domain which is typically required for their activities. Two of the fern proteins were effective against strains of fall armyworm that were resistant to Bt 3-domain Cry proteins Cry1Fa or Cry2A.127. This therefore represents a novel family of insecticidal proteins that have the potential to provide future tools for pest control.


Assuntos
Bacillus thuringiensis , Gleiquênias , Inseticidas , Traqueófitas , Animais , Inseticidas/metabolismo , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Controle Biológico de Vetores , Endotoxinas/genética , Endotoxinas/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Traqueófitas/metabolismo , Zea mays/metabolismo
4.
Small ; 20(17): e2307728, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38263806

RESUMO

Herein, the structure of integrated M3D inverters are successfully demonstrated where a chemical vapor deposition (CVD) synthesized monolayer WSe2 p-type nanosheet FET is vertically integrated on top of CVD synthesized monolayer MoS2 n-type film FET arrays (2.5 × 2.5 cm) by semiconductor industry techniques, such as transfer, e-beam evaporation (EBV), and plasma etching processes. A low temperature (below 250 °C) is employed to protect the WSe2 and MoS2 channel materials from thermal decomposition during the whole fabrication process. The MoS2 NMOS and WSe2 PMOS device fabricated show an on/off current ratio exceeding 106 and the integrated M3D inverters indicate an average voltage gain of ≈9 at VDD = 2 V. In addition, the integrated M3D inverter demonstrates an ultra-low power consumption of 0.112 nW at a VDD of 1 V. Statistical analysis of the fabricated inverters devices shows their high reliability, rendering them suitable for large-area applications. The successful demonstration of M3D inverters based on large-scale 2D monolayer TMDs indicate their high potential for advancing the application of 2D TMDs in future integrated circuits.

5.
Childs Nerv Syst ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578479

RESUMO

PURPOSE: Despite previous research supporting patient safety in sports after craniosynostosis surgery, parental anxiety remains high. This study sought to evaluate the role of healthcare providers in guiding patients and families through the decision-making process. METHODS: Parents of children with repaired craniosynostosis were asked to assess sports involvement and parental decision-making in children ages 6 and older. Questions were framed primarily on 5-point Likert scales. Sport categorizations were made in accordance with the American Academy of Pediatrics. Chi-squared, linear regression, and Pearson correlation tests were used to analyze associations between the questions. RESULTS: Forty-three complete parental responses were recorded. Mean ages at surgery and time of sports entry were 7.93 ± 4.73 months and 4.76 ± 2.14 years, respectively. Eighty-two percent of patients participated in a contact sport. Discussions with the primary surgeon were more impactful on parental decisions about sports participation than those with other healthcare providers (4.04 ± 1.20 vs. 2.69 ± 1.32). Furthermore, children whose parents consulted with the primary surgeon began participating in sports at a younger age (4.0 ± 1.0 vs. 5.8 ± 2.7 years, p = 0.034). The mean comfort level with contact sports (2.8 ± 1.4) was lower than that with limited-contact (3.8 ± 1.1, p = 0.0001) or non-contact (4.4 ± 1.3, p < 0.0001) sports. CONCLUSION: This study underscores the critical role that healthcare professionals, primarily surgeons, have in guiding families through the decision-making process regarding their children's participation in contact sports.

6.
Proc Natl Acad Sci U S A ; 118(16)2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879571

RESUMO

Most microorganisms in nature spend the majority of time in a state of slow or zero growth and slow metabolism under limited energy or nutrient flux rather than growing at maximum rates. Yet, most of our knowledge has been derived from studies on fast-growing bacteria. Here, we systematically characterized the physiology of the methanogenic archaeon Methanococcus maripaludis during slow growth. M. maripaludis was grown in continuous culture under energy (formate)-limiting conditions at different dilution rates ranging from 0.09 to 0.002 h-1, the latter corresponding to 1% of its maximum growth rate under laboratory conditions (0.23 h-1). While the specific rate of methanogenesis correlated with growth rate as expected, the fraction of cellular energy used for maintenance increased and the maintenance energy per biomass decreased at slower growth. Notably, proteome allocation between catabolic and anabolic pathways was invariant with growth rate. Unexpectedly, cells maintained their maximum methanogenesis capacity over a wide range of growth rates, except for the lowest rates tested. Cell size, cellular DNA, RNA, and protein content as well as ribosome numbers also were largely invariant with growth rate. A reduced protein synthesis rate during slow growth was achieved by a reduction in ribosome activity rather than via the number of cellular ribosomes. Our data revealed a resource allocation strategy of a methanogenic archaeon during energy limitation that is fundamentally different from commonly studied versatile chemoheterotrophic bacteria such as E. coli.


Assuntos
Metabolismo Energético/fisiologia , Mathanococcus/crescimento & desenvolvimento , Mathanococcus/metabolismo , Aclimatação/fisiologia , Archaea/genética , Biomassa , Carbono/metabolismo , Regulação da Expressão Gênica em Archaea/genética , Hidrogênio/metabolismo , Metano/metabolismo , Mathanococcus/fisiologia , Biologia de Sistemas/métodos
7.
J Am Chem Soc ; 145(19): 10790-10799, 2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-37133984

RESUMO

The ability to control the activation of prodrugs by transition metals has been shown to have great potential for controlled drug release in cancer cells. However, the strategies developed so far promote the cleavage of C-O or C-N bonds, which limits the scope of drugs to only those that present amino or hydroxyl groups. Here, we report the decaging of an ortho-quinone prodrug, a propargylated ß-lapachone derivative, through a palladium-mediated C-C bond cleavage. The reaction's kinetic and mechanistic behavior was studied under biological conditions along with computer modeling. The results indicate that palladium (II) is the active species for the depropargylation reaction, activating the triple bond for nucleophilic attack by a water molecule before the C-C bond cleavage takes place. Palladium iodide nanoparticles were found to efficiently trigger the C-C bond cleavage reaction under biocompatible conditions. In drug activation assays in cells, the protected analogue of ß-lapachone was activated by nontoxic amounts of nanoparticles, which restored drug toxicity. The palladium-mediated ortho-quinone prodrug activation was further demonstrated in zebrafish tumor xenografts, which resulted in a significant anti-tumoral effect. This work expands the transition-metal-mediated bioorthogonal decaging toolbox to include cleavage of C-C bonds and payloads that were previously not accessible by conventional strategies.


Assuntos
Naftoquinonas , Neoplasias , Pró-Fármacos , Animais , Humanos , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Paládio/química , Peixe-Zebra
8.
N Engl J Med ; 383(2): 109-119, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32640130

RESUMO

BACKGROUND: Tofersen is an antisense oligonucleotide that mediates the degradation of superoxide dismutase 1 (SOD1) messenger RNA to reduce SOD1 protein synthesis. Intrathecal administration of tofersen is being studied for the treatment of amyotrophic lateral sclerosis (ALS) due to SOD1 mutations. METHODS: We conducted a phase 1-2 ascending-dose trial evaluating tofersen in adults with ALS due to SOD1 mutations. In each dose cohort (20, 40, 60, or 100 mg), participants were randomly assigned in a 3:1 ratio to receive five doses of tofersen or placebo, administered intrathecally for 12 weeks. The primary outcomes were safety and pharmacokinetics. The secondary outcome was the change from baseline in the cerebrospinal fluid (CSF) SOD1 concentration at day 85. Clinical function and vital capacity were measured. RESULTS: A total of 50 participants underwent randomization and were included in the analyses; 48 participants received all five planned doses. Lumbar puncture-related adverse events were observed in most participants. Elevations in CSF white-cell count and protein were reported as adverse events in 4 and 5 participants, respectively, who received tofersen. Among participants who received tofersen, one died from pulmonary embolus on day 137, and one from respiratory failure on day 152; one participant in the placebo group died from respiratory failure on day 52. The difference at day 85 in the change from baseline in the CSF SOD1 concentration between the tofersen groups and the placebo group was 2 percentage points (95% confidence interval [CI], -18 to 27) for the 20-mg dose, -25 percentage points (95% CI, -40 to -5) for the 40-mg dose, -19 percentage points (95% CI, -35 to 2) for the 60-mg dose, and -33 percentage points (95% CI, -47 to -16) for the 100-mg dose. CONCLUSIONS: In adults with ALS due to SOD1 mutations, CSF SOD1 concentrations decreased at the highest concentration of tofersen administered intrathecally over a period of 12 weeks. CSF pleocytosis occurred in some participants receiving tofersen. Lumbar puncture-related adverse events were observed in most participants. (Funded by Biogen; ClinicalTrials.gov number, NCT02623699; EudraCT number, 2015-004098-33.).


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Oligonucleotídeos Antissenso/administração & dosagem , Oligonucleotídeos/administração & dosagem , Superóxido Dismutase-1/líquido cefalorraquidiano , Adulto , Esclerose Lateral Amiotrófica/líquido cefalorraquidiano , Esclerose Lateral Amiotrófica/genética , Progressão da Doença , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Cefaleia/induzido quimicamente , Humanos , Injeções Espinhais/efeitos adversos , Filamentos Intermediários , Leucocitose/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Mutação , Oligonucleotídeos/efeitos adversos , Oligonucleotídeos/farmacocinética , Oligonucleotídeos Antissenso/efeitos adversos , Oligonucleotídeos Antissenso/farmacocinética , Superóxido Dismutase-1/genética , Capacidade Vital
9.
N Engl J Med ; 383(2): 129-140, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32640131

RESUMO

BACKGROUND: Injuries from falls are major contributors to complications and death in older adults. Despite evidence from efficacy trials that many falls can be prevented, rates of falls resulting in injury have not declined. METHODS: We conducted a pragmatic, cluster-randomized trial to evaluate the effectiveness of a multifactorial intervention that included risk assessment and individualized plans, administered by specially trained nurses, to prevent fall injuries. A total of 86 primary care practices across 10 health care systems were randomly assigned to the intervention or to enhanced usual care (the control) (43 practices each). The participants were community-dwelling adults, 70 years of age or older, who were at increased risk for fall injuries. The primary outcome, assessed in a time-to-event analysis, was the first serious fall injury, adjudicated with the use of participant report, electronic health records, and claims data. We hypothesized that the event rate would be lower by 20% in the intervention group than in the control group. RESULTS: The demographic and baseline characteristics of the participants were similar in the intervention group (2802 participants) and the control group (2649 participants); the mean age was 80 years, and 62.0% of the participants were women. The rate of a first adjudicated serious fall injury did not differ significantly between the groups, as assessed in a time-to-first-event analysis (events per 100 person-years of follow-up, 4.9 in the intervention group and 5.3 in the control group; hazard ratio, 0.92; 95% confidence interval [CI], 0.80 to 1.06; P = 0.25). The rate of a first participant-reported fall injury was 25.6 events per 100 person-years of follow-up in the intervention group and 28.6 events per 100 person-years of follow-up in the control group (hazard ratio, 0.90; 95% CI, 0.83 to 0.99; P = 0.004). The rates of hospitalization or death were similar in the two groups. CONCLUSIONS: A multifactorial intervention, administered by nurses, did not result in a significantly lower rate of a first adjudicated serious fall injury than enhanced usual care. (Funded by the Patient-Centered Outcomes Research Institute and others; STRIDE ClinicalTrials.gov number, NCT02475850.).


Assuntos
Acidentes por Quedas/prevenção & controle , Lesões Acidentais/prevenção & controle , Administração dos Cuidados ao Paciente/métodos , Acidentes por Quedas/mortalidade , Acidentes por Quedas/estatística & dados numéricos , Lesões Acidentais/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Vida Independente , Masculino , Medicina de Precisão , Medição de Risco , Fatores de Risco
10.
Appl Environ Microbiol ; 89(3): e0162222, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36847510

RESUMO

IPD072Aa from Pseudomonas chlororaphis is a new insecticidal protein that has been shown to have high activity against western corn rootworm (WCR). IPD072 has no sequence signatures or predicted structural motifs with any known protein revealing little insight into its mode of action using bioinformatic tools. As many bacterially derived insecticidal proteins are known to act through mechanisms that lead to death of midgut cells, we evaluated whether IPD072Aa also acts by targeting the cells of WCR midgut. IPD072Aa exhibits specific binding to brush border membrane vesicles (BBMVs) prepared from WCR guts. The binding was found to occur at binding sites that are different than those recognized by Cry3A or Cry34Ab1/Cry35Ab1, proteins expressed by current maize traits that target WCR. Using fluorescence confocal microscopy, immuno-detection of IPD072Aa in longitudinal sections from whole WCR larvae that were fed IPD072Aa revealed the association of the protein with the cells that line the gut. High-resolution scanning electron microscopy of similar whole larval sections revealed the disruption of the gut lining resulting from cell death caused by IPD072Aa exposure. These data show that the insecticidal activity of IPD072Aa results from specific targeting and killing of rootworm midgut cells. IMPORTANCE Transgenic traits targeting WCR based on insecticidal proteins from Bacillus thuringiensis have proven effective in protecting maize yield in North America. High adoption has led to WCR populations that are resistant to the trait proteins. Four proteins have been developed into commercial traits, but they represent only two modes of action due to cross-resistance among three. New proteins suited for trait development are needed. IPD072Aa, identified from the bacterium Pseudomonas chlororaphis, was shown to be effective in protecting transgenic maize against WCR. To be useful, IPD072Aa must work through binding to different receptors than those utilized by current traits to reduce risk of cross-resistance and understanding its mechanism of toxicity could aid in countering resistance development. Our results show that IPD072Aa binds to receptors in WCR gut that are different than those utilized by current commercial traits and its targeted killing of midgut cells results in larval death.


Assuntos
Bacillus thuringiensis , Besouros , Inseticidas , Pseudomonas chlororaphis , Animais , Zea mays/metabolismo , Pseudomonas chlororaphis/metabolismo , Endotoxinas/farmacologia , Larva , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Inseticidas/metabolismo , Proteínas de Bactérias/metabolismo , Células Epiteliais , Plantas Geneticamente Modificadas/metabolismo , Controle Biológico de Vetores/métodos
11.
Med Care ; 61(11): 805-812, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37733394

RESUMO

OBJECTIVES: To evaluate the effectiveness and safety of Rehabilitation-at-Home (RaH), which provides high-frequency, multidisciplinary post-acute rehabilitative services in patients' homes. DESIGN: Comparative effectiveness analysis. SETTING AND PARTICIPANTS: Medicare Fee-For-Service patients who received RaH in a Center for Medicare and Medicaid Innovation Center Demonstration during 2016-2017 (N=173) or who received Medicare Skilled Nursing Facility (SNF) care in 2016-2017 within the same geographic service area with similar inclusion and exclusion criteria (N=5535). METHODS: We propensity-matched RaH participants to a cohort of SNF patients using clinical and demographic characteristics with exact match on surgical and non-surgical hospitalizations. Outcomes included hospitalization within 30 days of post-acute admission, death within 30 days of post-acute discharge, length of stay, falls, use of antipsychotic medication, and discharge to community. RESULTS: The majority of RaH participants were older than or equal to 85 years (57.8%) and non-Hispanic white (72.2%) with mean hospital length of stay of 8.1 (SD 7.6) days. In propensity-matched analyses, 10.1% (95% CI: 0.5%, 19.8) and 4.2% (95% CI: 0.1%, 8.5%) fewer RaH participants experienced hospital readmission and death, respectively. RaH participants had, on average, 2.8 fewer days (95% CI 1.4, 4.3) of post-acute care; 11.4% (95% CI: 5.2%, 17.7%) fewer RaH participants experienced fall; and 25.8% (95% CI: 17.8%, 33.9%) more were discharged to the community. Use of antipsychotic medications was no different. CONCLUSIONS AND IMPLICATIONS: RaH is a promising alternative to delivering SNF-level post-acute RaH. The program seems to be safe, readmissions are lower, and transition back to the community is improved.

12.
Exp Eye Res ; 233: 109543, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37390954

RESUMO

Several hypotheses have been tested to understand whole organ regulation in other organs such as the brain and kidney, but no such hypothesis has yet been proposed for ocular circulations. To some extent resolve this deficit our ex vivo mouse eye perfusion model takes the first step in elucidating the mechanisms controlling the individual components of the ocular circulation. Various isolated ocular vascular preparations have been utilized in studies of ocular vascular biology, physiology, and pharmacology, including studies on both normal and pathological conditions. However, there is still significant potential for further studies to improve our understanding of ocular circulation and its regulation. The choroid specifically is inaccessible to direct visualization due to the retina's high metabolic requirement with a transparency that cannot be compromised by an overly rich vascular network on the inner retinal side hindering the visualization of the choroid. In this technical paper, we provide a detailed description of all the steps to be followed from the enucleation of mouse eyes to cannulation of the ophthalmic artery and perfusion and ex vivo confocal microscopy imaging of the dynamic nature of the choroid circulation.


Assuntos
Corioide , Olho , Camundongos , Animais , Olho/irrigação sanguínea , Corioide/metabolismo , Retina , Perfusão/métodos , Artéria Oftálmica
13.
Soft Matter ; 19(9): 1782-1790, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36779927

RESUMO

The morphology of conjugated polymer thin films deposited by the resonant infrared matrix-assisted pulsed laser evaporation (RIR-MAPLE) process is related to the emulsion characteristics. However, a fundamental understanding of how and why the emulsion characteristics control the film properties and device performance is yet unclear. We performed all-atom molecular dynamics simulations of emulsions containing a mixture of polyfluorene (PFO) polymer, various primary solvents, secondary solvent, and water. The emulsion properties were then examined as a function of variable primary solvent and correlated with the morphology of deposited PFO thin films. The examination of the explicit interactions between all components of the emulsion indicated that using a primary solvent with a lower solubility-in-water and a higher non-bonded interaction energy ratio, between the solvent, polymer, and water in the emulsion recipe, produced the best result with smoother and denser films. Additionally, our simulation results are consistent with the AFM experimental results, indicating that interactions driven by trichlorobenzene (TCB) primary solvent within the emulsion are responsible for high-quality, smooth, and continuous thin film surfaces. Overall, this study can support the choice of a suitable primary solvent and provides the computational framework for predictions of new recipes for polymeric emulsion systems.

14.
Environ Sci Technol ; 57(34): 12838-12846, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37587565

RESUMO

As MPs are released into the soil, various equilibrium statuses are expected. MPs could play roles as a "source," a "cleaner," or a "sink" of HOCs. Three types of MPs (LDPE, PLA, and PS) were selected to study their effect on polychlorinated biphenyl (PCBs) relative bioavailability (RBA) measured by a mouse model. As a "source" of HOCs, exposure to MP-sorbed PCBs resulted in their accumulation in adipose tissue with PCB RBA as 101 ± 6.73% for LDPE, 76.2 ± 19.2% for PLA, and 9.22 ± 2.02% for PS. The addition of 10% MPs in PCB-contaminated soil led to a significant (p < 0.05) reduction in PCB RBA (52.2 ± 16.7%, 49.3 ± 4.85%, and 47.1 ± 5.99% for LDPE, PLA, and PS) compared to control (75.0 ± 4.26%), implying MPs acted as "cleaner" by adsorbing PCBs from the digestive system and reducing PCB accumulation. MPs acted as a "sink" for PCBs in contaminated soil after aging, but the sink effect varied among MP types with more pronounced effect for LDPE than PLA and PS. Therefore, the role played by MPs in bioavailability of HOCs closely depended on the MP types as well as the equilibrium status among MPs, soil, and HOCs.


Assuntos
Microplásticos , Bifenilos Policlorados , Animais , Camundongos , Disponibilidade Biológica , Plásticos , Polietileno , Poliésteres
15.
Environ Sci Technol ; 57(48): 19463-19472, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37943691

RESUMO

Prebiotics may stimulate beneficial gut microorganisms. However, it remains unclear whether they can lower the oral bioavailability of early life arsenic (As) exposure via regulating gut microbiota and altering As biotransformation along the gastrointestinal (GI) tract. In this study, weanling mice were exposed to arsenate (iAsV) via diet (7.5 µg As g-1) amended with fructooligosaccharides (FOS), galactooligosaccharides (GOS), and inulin individually at 1% and 5% (w/w). Compared to As exposure control mice, As concentrations in mouse blood, liver, and kidneys and As urinary excretion factor (UEF) were reduced by 43.7%-74.1% when treated with 5% GOS. The decrease corresponded to a significant proliferation of Akkermansia and Psychrobacter, reduced percentage of inorganic arsenite (iAsIII) and iAsV by 47.4% and 65.4%, and increased proportion of DMAV in intestinal contents by 101% in the guts of mice treated with 5% GOS compared to the As control group. In contrast, FOS and inulin either at l% or 5% did not reduce As concentration in mouse blood, liver, and kidneys or As UEF. These results suggest that GOS supplementation may be a gut microbiota-regulating approach to lower early life As exposure via stimulating the growth of Akkermansia and Psychrobacter and enhancing As methylation in the GI tract.


Assuntos
Arsênio , Microbioma Gastrointestinal , Camundongos , Animais , Inulina/metabolismo , Prebióticos , Fígado/metabolismo
16.
Environ Sci Technol ; 57(35): 12981-12990, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37615500

RESUMO

Few studies have investigated the long-term effect of exposure to arsenic (As), lead (Pb), and cadmium (Cd) via drinking water at the provisional guideline values on gut microflora. In this study, male and female mice were exposed to water As, Pb, or Cd at 10, 10, or 5 µg L-1 for 6 months. At the end of the exposure, the net weight gain of male mice exposed to As and Pb (9.91 ± 1.35 and 11.2 ± 1.50 g) was significantly (p < 0.05) lower compared to unexposed control mice (14.1 ± 3.24 g), while this was not observed for female mice. Relative abundance of Akkermansia, a protective gut bacterium against intestinal inflammation, was reduced from 29.7% to 3.20%, 4.83%, and 17.0% after As, Pb, and Cd exposure in male mice, which likely caused chronic intestinal inflammation, as suggested by 2.81- to 9.60-fold higher mRNA levels of pro-inflammatory factors in ileal enterocytes of male mice. These results indicate that long-term exposure to drinking water As, Pb, and Cd at concentrations equivalent to the China provisional guideline values can cause loss of protective bacteria and lead to chronic intestinal inflammation, thereby affecting body weight gain in male mice.


Assuntos
Arsênio , Água Potável , Microbioma Gastrointestinal , Feminino , Masculino , Animais , Camundongos , Cádmio/toxicidade , Chumbo , Inflamação/induzido quimicamente , Aumento de Peso
17.
Environ Sci Technol ; 57(2): 1017-1027, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36580282

RESUMO

Early-life arsenic (As) exposure is a particular health concern. However, it is unknown if As ingested early in life is more readily absorbed from the gastrointestinal (GI) tract, i.e., higher in oral bioavailability. Here, weanling (3-week) and adult (6-week-old) female mice were exposed to arsenate in the diet (10 µg g-1) over a 3-week period with As oral bioavailability estimated using As urinary excretion as the bioavailability endpoint. The As urinary excretion factor was 1.54-fold higher in weanling mice compared to adult mice (82.2 ± 7.29 versus 53.1 ± 3.73%), while weanling mice also showed 2.28-, 1.50-, 1.48-, and 1.89-fold higher As concentration in small intestine tissue, blood, liver, and kidneys, demonstrating significantly higher As oral bioavailability of early-life exposure. Compared to adult mice, weanling mice significantly differed in gut microbiota, but the difference did not lead to remarkable differences in As biotransformation in the GI tract or tissue and in overall gut metabolite composition. Although the expression of several metabolites (e.g., atrolactic acid, hydroxyphenyllactic acid, and xanthine) was up-regulated in weanling mice, they had limited ability to elevate As solubility in the intestinal tract. Compared to adult mice, the intestinal barrier function and intestinal expression of phosphate transporters responsible for arsenate absorption were similar in weanling mice. However, the small intestine of weanling mice was characterized by more defined intestinal villi with greater length and smaller width, providing a greater surface area for As to be absorbed across the GI barrier. The results highlight that early-life As exposure can be more readily absorbed, advancing the understanding of its health risk.


Assuntos
Arsênio , Microbioma Gastrointestinal , Animais , Camundongos , Feminino , Arseniatos , Mucosa Intestinal/metabolismo
18.
J Endocrinol Invest ; 46(4): 829-840, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36334246

RESUMO

PURPOSE: CDKN1B mutations were established as a cause of multiple endocrine neoplasia 4 (MEN4) syndrome in patients with MEN1 phenotype without a mutation in the MEN1 gene. In addition, variants in other cyclin-dependent kinase inhibitors (CDKIs) were found in some MEN1-like cases without the MEN1 mutation. We aimed to describe novel germline mutations of these genes in patients with primary hyperparathyroidism (PHPT). METHODS: During genetic screening for familial hyperparathyroidism, three novel CDKIs germline mutations in three unrelated cases between January 2019 and November 2021 were identified. In this report, we describe clinical features, DNA sequence analysis, and familial segregation studies based on these patients and their relatives. Genome-wide DNA study of loss of heterozygosity (LOH), copy number variation (CNV), and p27/kip immunohistochemistry was performed on tumour samples. RESULTS: DNA screening was performed for atypical parathyroid adenomas in cases 1 and 2 and for cystic parathyroid adenoma and young age at diagnosis of PHPT in case 3. Genetic analysis identified likely pathogenic variants of CDKN1B in cases 1 and 2 and a variant of the uncertain significance of CDKN2C, with uniparental disomy in the tumour sample, in case 3. Neoplasm screening of probands showed other non-endocrine tumours in case 1 (colon adenoma with dysplasia and atypical lipomas) and case 2 (aberrant T-cell population) and a non-functional pituitary adenoma in case 3. CONCLUSION: Germline mutations in CDKIs should be included in gene panels for genetic testing of primary hyperparathyroidism. New germline variants here described can be added to the current knowledge.


Assuntos
Hiperparatireoidismo Primário , Neoplasia Endócrina Múltipla Tipo 1 , Neoplasias , Humanos , Mutação em Linhagem Germinativa , Hiperparatireoidismo Primário/diagnóstico , Hiperparatireoidismo Primário/genética , Hiperparatireoidismo Primário/patologia , Variações do Número de Cópias de DNA , DNA/genética , Células Germinativas/patologia , Inibidor de Quinase Dependente de Ciclina p27/genética , Inibidor de Quinase Dependente de Ciclina p18/genética
19.
Arch Toxicol ; 97(1): 255-261, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36329301

RESUMO

Chloropicrin (CP) is a common agricultural fumigant historically used as a chemical warfare agent and is a concern for potential use in warfare and terrorist applications. Our inability to effectively treat CP-induced injuries makes it essential to better understand CP toxicity. We set out to elucidate variables that must be understood to achieve optimal exposure conditions for in vitro investigations given that such models are important for the study of CP injury and potential therapeutics. To this end, we evaluated the effects of volatility, cell seeding density, and serum concentration of cell culture medium on CP toxicity in an immortalized human corneal epithelial cell line. We found that even with very dilute solutions, CP remained highly volatile, so much so that a 0.0019% CP solution resulted in 90% cell death at time 0, but was nearly nontoxic 45 min later. Not surprisingly, the CP-induced IL-8 response was shown to vary with cell viability in this experiment. After exposure with 0.00115% CP, cells that were 12% confluent experienced over 40% more cell death than cells exposed at 87% confluency. Exposure with the same CP dose in medium containing concentrations of fetal bovine serum (FBS) ranging from 0.1% to 15% exhibited a 17% difference in cell viability. Given that chemical toxicity can be significantly influenced by volatility, cell density, and serum content of cell culture medium, these phenomena should be explored during the development and optimization of toxicant exposure models.


Assuntos
Substâncias para a Guerra Química , Hidrocarbonetos Clorados , Humanos , Hidrocarbonetos Clorados/toxicidade , Hidrocarbonetos Clorados/química , Substâncias para a Guerra Química/toxicidade , Morte Celular , Técnicas de Cultura de Células
20.
Int J Behav Med ; 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37254029

RESUMO

BACKGROUND: Type 2 diabetes mellitus (T2DM) disproportionally impacts Latin Americans (Latinos) in the U.S. compared to non-Latino Whites, as reflected by an increased risk for disease complications and higher mortality rates. Guided by an Integrative Model of Culture, Psychological Processes, and Health Behavior, the purpose of the present study was to examine the role of cultural beliefs and diabetes distress as determinants of self-care behaviors and HbA1c among Latino patients with T2DM. METHODS: Participants included 109 Latino patients with T2DM recruited from a diabetes treatment center located in a region of Southern California with high diabetes mortality rates. Structural equation modeling was employed to examine the extent to which cultural beliefs about diabetes-related social exclusion and diabetes distress impact self-care behaviors and self-reported HbA1c. RESULTS: Consistent with the study hypotheses, cultural beliefs about diabetes-related social exclusion predicted diabetes distress, which in turn predicted poor diabetes self-care. CONCLUSIONS: Findings suggest an important need for intervention efforts that address both cultural and psychological factors in order to improve diabetes self-care behaviors and associated disease outcomes among Latino patients with T2DM. Future research could benefit from investigating protective aspects of culture that could help counter the negative implications of cultural beliefs about social exclusion and diabetes distress associated with poor self-care.

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