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1.
Am J Infect Control ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38871085

RESUMO

We conducted a quality improvement project from 2019 to 2021 at a single home health agency to reduce rates of central line-associated bloodstream infection in our ambulatory pediatric population. Annualized central line-associated bloodstream infection rates per 1,000 catheter line days decreased by 20 % during the study period, from a rate of 1.023 to 0.810. This decrease was sustained in the 10-month post-study period with a center line shift of 1.090 to 0.658.

2.
Pharmacy (Basel) ; 12(3)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38804470

RESUMO

Buprenorphine is a semi-synthetic long-acting partial µ-opioid receptor (MOR) agonist that can be used for chronic pain as a sublingual tablet, transdermal patch (Butrans®), or a buccal film (Belbuca®). Buprenorphine's unique high receptor binding affinity and slow dissociation at the MOR allow for effective analgesia while offering less adverse effects compared to a full agonist opioid, in particular, less concern for respiratory depression and constipation. It is underused in chronic pain and palliative care due to misconceptions and stigma from its use in opioid use disorder (OUD). This case report discusses the unique pharmacology of buprenorphine, including its advantages, disadvantages, available formulations, drug-drug interactions, initiation and conversion strategies, and identifies ideal populations for use, especially within the palliative care patient population.

3.
Pharmacy (Basel) ; 12(2)2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38668087

RESUMO

Palliative care plays a crucial role in enhancing the quality of life for individuals facing serious illnesses, aiming to alleviate suffering and provide holistic support. With the advent of telehealth, there is a growing interest in leveraging technology to extend the reach and effectiveness of palliative care services. This article provides a comprehensive review of the evolution of telehealth, the current state of telemedicine in palliative care, and the role of telepharmacy and medication management. Herein we highlight the potential benefits, challenges, and future directions of palliative telemedicine. As the field continues to advance, the article proposes key considerations for future research, policy development, and clinical implementation, aiming to maximize the advantages of telehealth in assisting individuals and their families throughout the palliative care journey. The comprehensive analysis presented herein contributes to a deeper understanding of the role of telehealth in palliative care and serves as a guide for shaping its future trajectory.

4.
Pharmacy (Basel) ; 12(2)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38525727

RESUMO

Most patients with pancreatic cancer at some point present with symptoms related to exocrine pancreatic insufficiency (EPI). These include diarrhea, abdominal bloating, indigestion, steatorrhea, weight loss, and anorexia. Even though up to 80% of pancreatic cancer patients eventually present with symptoms related to exocrine pancreatic insufficiency, only 21% are prescribed pancreatic enzyme replacement therapy (PERT). Its effectiveness is also highly dependent on its proper timing of administration, and patients must be thoroughly educated about this. The impact of symptoms of EPI can lead to poorer overall well-being. Pharmacists play a crucial role in properly educating patients on the correct use of pancreatic enzyme replacement therapy. PERT is a key strategy in managing the symptoms of EPI and can improve quality of life, which is a central focus in palliative care. This treatment is profoundly underutilized in the palliative care of these patients. The objective of this review is to discuss the pharmacology, pharmacokinetics, side effects, available evidence of the effectiveness of pancreatic enzyme use for patients with pancreatic cancer, and challenges, along with proposed solutions regarding its use.

5.
Pharmacy (Basel) ; 12(2)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38525728

RESUMO

BACKGROUND: Opioid-induced constipation (OIC) is a pervasive and distressing side effect of chronic opioid therapy in patients with cancer pain, significantly impacting their quality of life. Peripherally acting µ-opioid receptor antagonists (PAMORAS) were developed for treatment-resistant OIC but most studies were conducted with non-cancer patients. OBJECTIVE: to discuss two oral formulations of PAMORAs, naldemedine and naloxegol, and to review available evidence of the effectiveness of these drugs for OIC in cancer patients. METHODS: a comprehensive search to identify primary literature for either naldemedine or naloxegol for OIC in cancer patients. RESULTS: Only three prospective randomized, double-blind, placebo-controlled clinical trials for naldemedine enrolling cancer patients were identified; the results of a subgroup analysis of two of those studies and two non-interventional post marketing surveillance studies of these trials are also reported here. For naloxegol, only two randomized controlled trials were identified; both were unsuccessful in enrolling sufficient patients. An additional four prospective non-interventional observational studies with naloxegol were found that enrolled cancer patients. There were significantly higher rates of responders in the PAMORA groups than in the placebo groups. The most common side effect for both PAMORAs was diarrhea. LIMITATIONS: All studies were industry-funded, and given that only three trials were randomized controlled studies, the overall quality of the studies was lacking. CONCLUSION: Naldemedine or naloxegol appeared safe and useful in the treatment of OIC in cancer patients and may improve their quality of life. Larger-scale randomized placebo-controlled studies of PAMORAs in cancer patients would strengthen existing evidence.

6.
Plant Physiol ; 195(2): 1694-1711, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38378170

RESUMO

The root system plays an essential role in plant growth and adaptation to the surrounding environment. The root clock periodically specifies lateral root prebranch sites (PBS), where a group of pericycle founder cells (FC) is primed to become lateral root founder cells and eventually give rise to lateral root primordia or lateral roots (LRs). This clock-driven organ formation process is tightly controlled by modulation of auxin content and signaling. Auxin perception entails the physical interaction of TRANSPORT INHIBITOR RESPONSE 1 (TIR1) or AUXIN SIGNALING F-BOX (AFBs) proteins with AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) repressors to form a co-receptor system. Despite the apparent simplicity, the understanding of how specific auxin co-receptors are assembled remains unclear. We identified the compound bis-methyl auxin conjugated with N-glucoside, or BiAux, in Arabidopsis (Arabidopsis thaliana) that specifically induces the formation of PBS and the emergence of LR, with a slight effect on root elongation. Docking analyses indicated that BiAux binds to F-box proteins, and we showed that BiAux function depends on TIR1 and AFB2 F-box proteins and AUXIN RESPONSE FACTOR 7 activity, which is involved in FC specification and LR formation. Finally, using a yeast (Saccharomyces cerevisiae) heterologous expression system, we showed that BiAux favors the assemblage of specific co-receptors subunits involved in LR formation and enhances AUXIN/INDOLE-3-ACETIC ACID 28 protein degradation. These results indicate that BiAux acts as an allosteric modulator of specific auxin co-receptors. Therefore, BiAux exerts a fine-tune regulation of auxin signaling aimed to the specific formation of LR among the many development processes regulated by auxin.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ácidos Indolacéticos , Raízes de Plantas , Ácidos Indolacéticos/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/genética , Arabidopsis/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Transdução de Sinais , Proteínas F-Box/metabolismo , Proteínas F-Box/genética , Reguladores de Crescimento de Plantas/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores de Superfície Celular/genética
9.
BMJ Glob Health ; 8(7)2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37423621

RESUMO

High-level isolation units (HLIUs) are specially designed facilities for care and management of patients with suspected or confirmed high-consequence infectious diseases (HCIDs), equipped with unique infrastructure and operational features. While individual HLIUs have published on their experiences caring for patients with HCIDs and two previous HLIU consensus efforts have outlined key components of HLIUs, we aimed to summarise the existing literature that describes best practices, challenges and core features of these specialised facilities. A narrative review of the literature was conducted using keywords associated with HLIUs and HCIDs. A total of 100 articles were used throughout the manuscript from the literature search or from alternate methods like reference checks or snowballing. Articles were sorted into categories (eg, physical infrastructure, laboratory, internal transport); for each category, a synthesis of the relevant literature was conducted to describe best practices, experiences and operational features. The review and summary of HLIU experiences, best practices, challenges and components can serve as a resource for units continuing to improve readiness, or for hospitals in early stages of developing their HLIU teams and planning or constructing their units. The COVID-19 pandemic, a global outbreak of mpox, sporadic cases of viral haemorrhagic fevers in Europe and the USA, and recent outbreaks of Lassa fever, Sudan Ebolavirus, and Marburg emphasise the need for an extensive summary of HLIU practices to inform readiness and response.


Assuntos
COVID-19 , Doenças Transmissíveis , Febres Hemorrágicas Virais , Humanos , Pandemias , COVID-19/epidemiologia , Doenças Transmissíveis/epidemiologia , Febres Hemorrágicas Virais/epidemiologia , Surtos de Doenças/prevenção & controle
10.
World Neurosurg ; 170: e827-e833, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36481445

RESUMO

OBJECTIVE: We sought to determine the concordance in frequency of microbiologic isolation and species identification in specimens obtained by 2 methods. METHODS: Intervertebral disk specimens were taken simultaneously from each patient using percutaneous needle and posterolateral endoscopic biopsies. The isolates were reported in frequencies and concordance using the chi square and Cohen kappa tests. RESULTS: Thirty patients were recruited. The average age was 58.1 years, and 15 patients were women. The clinical evolution time was 7 ± 4 months. The causative organism was identified in 12 (40%) specimens obtained by fluoroscopy-guided percutaneous transpedicular biopsy and in 14 (46.6%) obtained by posterolateral endoscopy. The most common organism isolated was Staphylococcus aureus in 3 patients with the percutaneous technique and in 5 with the endoscopic one; Escherichia coli was isolated in 3 patients with each method. The kappa test showed a high degree of agreement between both methods (kappa = 0.86); the agreement in bacterial species identification was 100%. CONCLUSIONS: Fluoroscopy-guided percutaneous biopsy and endoscopic sampling have a good degree of concordance for both, frequency of organism isolation and identification in patients with infectious spondylodiskitis.


Assuntos
Discite , Disco Intervertebral , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Discite/diagnóstico por imagem , Discite/cirurgia , Endoscopia , Fluoroscopia , Biópsia , Endoscopia Gastrointestinal , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Vértebras Lombares/patologia
11.
Plant Commun ; 4(3): 100514, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-36585788

RESUMO

Climate change is increasing the frequency of extreme heat events that aggravate its negative impact on plant development and agricultural yield. Most experiments designed to study plant adaption to heat stress apply homogeneous high temperatures to both shoot and root. However, this treatment does not mimic the conditions in natural fields, where roots grow in a dark environment with a descending temperature gradient. Excessively high temperatures severely decrease cell division in the root meristem, compromising root growth, while increasing the division of quiescent center cells, likely in an attempt to maintain the stem cell niche under such harsh conditions. Here, we engineered the TGRooZ, a device that generates a temperature gradient for in vitro or greenhouse growth assays. The root systems of plants exposed to high shoot temperatures but cultivated in the TGRooZ grow efficiently and maintain their functionality to sustain proper shoot growth and development. Furthermore, gene expression and rhizosphere or root microbiome composition are significantly less affected in TGRooZ-grown roots than in high-temperature-grown roots, correlating with higher root functionality. Our data indicate that use of the TGRooZ in heat-stress studies can improve our knowledge of plant response to high temperatures, demonstrating its applicability from laboratory studies to the field.


Assuntos
Ecossistema , Raízes de Plantas , Temperatura , Raízes de Plantas/metabolismo , Meristema , Temperatura Alta , Plantas
12.
Integr Cancer Ther ; 21: 15347354221101630, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35603438

RESUMO

BACKGROUND: A prior phase III, multicenter (United States and China), clinical trial found true acupuncture (TA) resulted in lower xerostomia scores 12 months after radiotherapy than that of a standard care control group. This small pilot study examined brain function changes comparing TA to sham acupuncture (SA) in US and Fudan patients undergoing head and neck radiotherapy. METHODS: To determine cerebral activity during TA versus SA acupuncture, patients underwent electroencephalogram evaluation (EEG) immediately prior, during and after both conditions. Acupuncture occurred during weeks 3 to 5 of radiotherapy, with patients receiving either TA or SA, followed 2 to 3 days later by the other treatment in a counterbalanced manner. RESULTS: In the TA minus SA condition (N = 14 Fudan; N = 13 US), most changes were in the delta (0.5-3.5 Hz) and alpha (8-12 Hz) bandwidths. Delta was present in the frontal gyrus and parahippocampal gyrus. Alpha was present in the anterior and posterior cingulate, lingual gyrus, amygdala, precuneus, medial frontal gyrus, fusiform gyrus, and superior frontal gyrus. Maximal cortical differences in the Fudan cohort between TA and SA were in areas previously shown to be associated with (TA). In the US cohort, maximal differences between TA and SA were associated with areas which are usually decreased in TA conditions. CONCLUSIONS: There were distinct differences in brain function between those receiving TA and SA and there were clear differences between cultures, helping to explain the lack of placebo effect in the Fudan participants and strong placebo effect in the US patients.


Assuntos
Terapia por Acupuntura , Neoplasias de Cabeça e Pescoço , Xerostomia , Terapia por Acupuntura/métodos , Encéfalo , Comparação Transcultural , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Projetos Piloto , Xerostomia/etiologia , Xerostomia/terapia
13.
Pathogens ; 10(10)2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34684266

RESUMO

Tick-borne diseases (TBDs) considerably impair equine health and productivity. Moreover, TBDs, particularly equine piroplasmosis, impede international movement and trade of equids, which is a vital component of the global horse racing industry. In the Philippines, horse racing is a lucrative industry generating millions of USD annually. However, information on equine TBDs is scarce. This study intended to describe molecularly the equine tick-borne infections in a racehorse park in Cavite, Philippines and identify the risk factors associated with the infections. One hundred twenty-four (n = 124) thoroughbred racehorses were sampled and screened for selected tick-borne protozoan and bacterial pathogens using polymerase chain reaction (PCR) assays. Racehorses were positive for Babesia caballi (12.10%; 15/124), Theileria equi (0.81%; 1/124), Anaplasma phagocytophilum (10.48%; 13/124), Borrelia burgdorferi sensu lato (38.71%; 48/124), A. marginale (0.81%; 1/124), and Coxiella burnetii (0.81%; 1/124). Rickettsia was not detected in the samples. Gender was determined as a significant risk factor for B. caballi infection. Sequencing analysis revealed that seven partial 18S rRNA B. caballi isolates shared 98.63-100% identity with each other and were classified as genotype A. Meanwhile, the sequence obtained from the lone T. equi-positive sample was 99.77% identical to isolates from Spain, Switzerland, China, Saudi Arabia, and South Korea, and was confirmed as genotype E based on the 18S rRNA gene. Eight Anaplasma 16S rRNA partial sequences were highly identical to A. phagocytophilum and A. ovis. Partial sequences of Borrelia 5-23S rRNA were most closely related to B. japonica and other Borrelia sp. isolates from various countries. This study reports the first molecular detection of Borrelia and Anaplasma and the identification of B. caballi and T. equi genotypes in racehorses in the Philippines. Findings from this study shall be useful in crafting equine tick and TBD control and prevention programs in the country.

14.
Pathogens ; 10(8)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34451485

RESUMO

Sepsis, resulting from a dysregulated host immune response to invading pathogens, is the leading cause of mortality in critically ill patients worldwide. Immunomodulatory treatment for sepsis is currently lacking. Children with short bowel syndrome (SBS) may present with less severe symptoms during gram-negative bacteremia. We, therefore, tested the hypothesis that plasma from children with SBS could confer protection against Escherichia coli sepsis. We showed that SBS plasma at 5% and 10% concentrations significantly (p < 0.05) inhibited the production of both TNF-α and IL-6 induced by either E. coli- or LPS-stimulated host cells when compared to plasma from healthy controls. Furthermore, mice treated intravenously with select plasma samples from SBS or healthy subjects had reduced proinflammatory cytokine levels in plasma and a significant survival advantage after E. coli infection. However, SBS plasma was not more protective than the plasma of healthy subjects, suggesting that children with SBS have other immunomodulatory mechanisms, in addition to neutralizing antibodies, to alleviate their symptoms during gram-negative sepsis.

15.
J Phycol ; 57(5): 1604-1618, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34124800

RESUMO

The frequency of marine heatwaves (MHWs) is increasing due to climate change. Although seaweeds are resilient to environmental changes, an increasing body of evidence shows that rising sea surface temperatures have deleterious effects on temperate kelp species. However, information on the vulnerability of juvenile kelp to these stressors and their population stability is limited. This study summarizes findings on the ability of juvenile sporophytes of Macrocystis pyrifera to survive and recover from simulated MHW conditions (22°C, 5 d) in combination with nitrate limitation (<1 µM) by evaluating photosynthetic capacity, nitrate uptake, tissue composition, bio-optical properties, and oxidative stress of single-blade juvenile sporophytes (<20 cm). Temperature, nitrate availability, and their interaction had significant effects on the physiological status of juvenile sporophytes after the exposure and recovery periods. Overall, as expected, the photosynthetic capacity of juvenile sporophytes decreased with increased temperature and lower nitrate availability. Short-term exposure to simulated MHWs resulted in oxidative damage and reduced growth. The termination of the experimental warming allowed partial recovery to control values, indicating high physiological resilience. However, the interaction of both high temperature and nitrate scarcity induced irreversible damage to their photosynthetic capacity, with an increase in compensation irradiance, highlighting potential limitations in the carbon balance of juvenile sporophytes.


Assuntos
Kelp , Macrocystis , Mudança Climática , Nitratos , Fotossíntese
16.
J Cardiothorac Vasc Anesth ; 35(4): 1030-1036, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33384230

RESUMO

OBJECTIVES: Use of viscoelastic testing, such as thromboelastography (TEG), is recommended in cardiac surgery to monitor coagulation and to guide the transfusion of blood products. The Quantra QPlus System is a novel point-of-care platform that uses ultrasonic pulses to characterize dynamic changes in viscoelastic properties of a blood sample during coagulation. Despite the ability to assess similar aspects of clot formation, limited studies addressing the interchangeability of viscoelastic testing parameters exist. The primary aim of the present study was to assess the correlation and agreement between Quantra and TEG5000 results using blood samples from cardiac surgery patients. DESIGN: Tertiary care, academic medical center. SETTING: Prospective observational study. PARTICIPANTS: Twenty-eight patients undergoing elective cardiac surgery undergoing cardiopulmonary bypass were evaluated. MEASUREMENTS AND MAIN RESULTS: Perioperative blood samples were collected and assessed using Quantra, and results were compared with TEG and conventional coagulation testing. Method comparison analysis demonstrated that Quantra parameters (Quantra clot time, clot stiffness, and fibrinogen contribution to clot stiffness) significantly correlated with TEG R and TEG G after induction of anesthesia, during cardiopulmonary bypass, and after rewarming (rs = 0.83, rs = 0.84, and rs = 0.73, respectively). However, Quantra parameters demonstrated poor agreement compared with equivalent TEG5000 parameters. CONCLUSIONS: The Quantra QPlus System significantly correlated with TEG5000, suggesting that this test may be used in a similar clinical context. Despite the strength of correlation between Quantra and TEG parameters, measurements are not interchangeable.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Tromboelastografia , Coagulação Sanguínea , Testes de Coagulação Sanguínea , Ponte Cardiopulmonar , Humanos , Estudos Prospectivos
17.
EClinicalMedicine ; 24: 100440, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32637904

RESUMO

BACKGROUND: Current point-of-care tests (POCT) for syphilis, based on the detection of Treponema pallidum (TP) total antibodies, have limited capacity in distinguishing between active and past/treated syphilis. We report the development and early evaluation of a new prototype POCT based on the detection of TP-IgA antibodies, a novel biomarker for active syphilis. METHODS: The TP-IgA POCT (index test) was developed in response to the World Health Organisation (WHO) target product profile (TPP) for a POCT for confirmatory syphilis testing. Two sub-studies were conducted consecutively using 458 pre-characterised stored plasma samples in China (sub-study one, addressing the criteria for the WHO TPP), and 503 venous blood samples collected from pregnant/postpartum women in South Africa (sub-study two, addressing potential clinical utility). Performance of the index test was assessed against standard laboratory-based serology using a combination of treponemal (TPHA) and non-treponemal (rapid plasma reagin [RPR]) tests. FINDINGS: In sub-study one, the index test demonstrated 96·1% (95%CI=91·7%-98·5%) sensitivity and 84·7% (95%CI=80·15-88·6%) specificity for identification of active syphilis (TPHA positive, RPR positive). It correctly identified 71% (107/150) samples of past-treated syphilis (TPHA positive, RPR negative). In sub-study two, the index test achieved 100% (95%CI=59%-100%) sensitivity for active syphilis and correctly identified all nine women with past syphilis. INTERPRETATION: The TP-IgA POCT has met the WHO TPP for a POCT for diagnosis of active syphilis and demonstrated its potential utility in a clinical setting. Future studies are warranted to evaluate field performance of the final manufactured test. FUNDING: Saving Lives at Birth: Grand Challenge for Development, Thrasher Research Fund, and the Victorian Government Operational Infrastructure Scheme.

18.
Am J Geriatr Psychiatry ; 28(8): 835-838, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32430111

RESUMO

Nursing homes are facing the rapid spread of COVID-19 among residents and staff and are at the centre of the public health emergency due to the COVID-19 pandemic. As policy changes and interventions designed to support nursing homes are put into place, there are barriers to implementing a fundamental, highly effective element of infection control, namely the isolation of suspected or confirmed cases. Many nursing home residents have dementia, associated with impairments in memory, language, insight, and judgment that impact their ability to understand and appreciate the necessity of isolation and to voluntarily comply with isolation procedures. While there is a clear ethical and legal basis for the involuntary confinement of people with dementia, the potential for unintended harm with these interventions is high, and there is little guidance for nursing homes on how to isolate safely, while maintaining the human dignity and personhood of the individual with dementia. In this commentary, we discuss strategies for effective, safe, and compassionate isolation care planning, and present a case vignette of a person with dementia who is placed in quarantine on a dementia unit.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Demência/terapia , Casas de Saúde/normas , Pandemias/prevenção & controle , Isolamento de Pacientes/métodos , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , Quarentena/métodos , Idoso , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/transmissão , Demência/complicações , Feminino , Humanos , Tratamento Involuntário/ética , Tratamento Involuntário/métodos , Isolamento de Pacientes/ética , Pneumonia Viral/complicações , Pneumonia Viral/transmissão , Quarentena/ética , SARS-CoV-2
19.
Plants (Basel) ; 9(4)2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32295129

RESUMO

Fluorescence-activated cell sorting (FACS) is a technique used to isolate specific cell populations based on characteristics detected by flow cytometry. FACS has been broadly used in transcriptomic analyses of individual cell types during development or under different environmental conditions. Different protoplast extraction protocols are available for plant roots; however, they were designed for accessible cell populations, which normally were grown in the presence of light, a non-natural and stressful environment for roots. Here, we report a protocol using FACS to isolate root protoplasts from Arabidopsis green fluorescent protein (GFP)-marked lines using the minimum number of enzymes necessary for an optimal yield, and with the root system grown in darkness in the D-Root device. This device mimics natural conditions as the shoot grows in the presence of light while the roots grow in darkness. In addition, we optimized this protocol for specific patterns of scarce cell types inside more differentiated tissues using the mCherry fluorescent protein. We provide detailed experimental protocols for effective protoplasting, subsequent purification through FACS, and RNA extraction. Using this RNA, we generated cDNA and sequencing libraries, proving that our methods can be used for genome-wide transcriptomic analyses of any cell-type from roots grown in darkness.

20.
J Phycol ; 56(2): 380-392, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31804706

RESUMO

This study was designed to understand better if and how juvenile sporophytes of Macrocystis pyrifera can photoacclimate to high-light conditions when transplanted from 10 to 3 meters over 7 d. Acclimation of adult sporophytes to light regimes in the bathymetric gradient has been extensively documented. It primarily depends on photoacclimation and translocation of resources among blades. Among other physiological differences, juvenile sporophytes of M. pyrifera lack the structural complexity shown by adults. As such, juveniles may primarily depend on their photoacclimation capacities to maintain productivity and even avoid mortality under changing light regimes. However, little is known about how these mechanisms operate in young individuals. The capacity of sporophytes to photoacclimate was assessed by examining changes in their photosynthetic performance, pigment content, and bio-optical properties of the blade. Sporophytes nutritional status and oxidative damage were also determined. Results showed that juvenile sporophytes transplanted to shallow water were able to regulate light harvesting by reducing pigment concentration, and thus, absorptance and photosynthetic efficiency. Also, shallow-water sporophytes notably enhanced the dissipation of light energy as heat (NPQ) as a photoprotective mechanism. Generally, these adjustments allowed sporophytes to manage the absorption and utilization of light energy, hence reducing the potential for photo-oxidative damage. Furthermore, no substantial changes were found in the internal reserves (i.e., soluble carbohydrates and nitrogen) of these sporophytes. To our knowledge, these results are the first to provide robust evidence of photoprotective and photoacclimation strategies in juveniles of M. pyrifera, allowing them to restrict or avoid photodamage during shallow-water cultivation.


Assuntos
Macrocystis , Aclimatação , Nitrogênio , Fotossíntese , Água
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