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1.
J Microsc ; 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38808665

RESUMO

We propose a smartphone-based optical sectioning (SOS) microscope based on the HiLo technique, with a single smartphone replacing a high-cost illumination source and a camera sensor. We built our SOS with off-the-shelf optical, mechanical cage systems with 3D-printed adapters to seamlessly integrate the smartphone with the SOS main body. The liquid light guide can be integrated with the adapter, guiding the smartphone's LED light to the digital mirror device (DMD) with neglectable loss. We used an electrically tuneable lens (ETL) instead of a mechanical translation stage to realise low-cost axial scanning. The ETL was conjugated to the objective lens's back pupil plane (BPP) to construct a telecentric design by a 4f configuration to maintain the lateral magnification for different axial positions. SOS has a 571.5 µm telecentric scanning range and an 11.7 µm axial resolution. The broadband smartphone LED torch can effectively excite fluorescent polystyrene (PS) beads. We successfully used SOS for high-contrast fluorescent PS beads imaging with different wavelengths and optical sectioning imaging of multilayer fluorescent PS beads. To our knowledge, the proposed SOS is the first smartphone-based HiLo optical sectioning microscopy (£1965), which can save around £7035 compared with a traditional HiLo system (£9000). It is a powerful tool for biomedical research in resource-limited areas.

2.
Intern Med J ; 52(10): 1780-1790, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34139100

RESUMO

BACKGROUND: The incidence of end-stage organ disease in people living with human immunodeficiency virus (HIV) (PLWH) is increasing, as people live longer due to potent, tolerable antiretroviral therapy (ART). Consequently, the number of PLWH who would benefit from solid organ transplant (SOT) is rising. The SOT experience in PLWH in Australia remains limited. Aim To retrospectively review the outcomes for SOT in PLWH at our service, in Victoria, Australia. METHODS: A retrospective cohort study of PLWH undergoing SOT over a 15-year period was performed. Adult PLWH age >18 years were eligible and identified from the Victorian HIV Service database. Descriptive statistics were used to summarise baseline demographics and clinical data, and outcomes following SOT. RESULTS: Nine virologically suppressed PLWH underwent SOT from HIV-negative donors (five kidneys, two livers and two bilateral sequential lung transplants). All patients were male, with a median age of 57.3 years (interquartile range (IQR) = 54.3-60.1) and CD4 count of 485 (IQR = 342-835) at transplantation, and comorbidities were common at baseline. After a median follow up of 3.9 years (IQR = 2.7-7.6), 8 (89%) patents were alive, 7 (78%) had functioning grafts, although 5 (56%) experienced organ rejection. Infections were common. Two patients required modification to their ART due to significant drug-drug interactions prior to transplant, while 5 (56%) had modifications post-SOT. No patients experienced HIV virologic failure. CONCLUSION: PLWH with end-stage organ disease experience good clinical and functional outcomes and should be considered for SOT where indicated. However, multidisciplinary planning and care is essential to optimise care in this patient group.


Assuntos
Infecções por HIV , Transplante de Órgãos , Adulto , Masculino , Humanos , Pessoa de Meia-Idade , Adolescente , Feminino , Estudos Retrospectivos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , HIV , Vitória/epidemiologia
4.
Transpl Infect Dis ; 23(2): e13510, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33217119

RESUMO

Infections caused by carbapenemase-producing Enterobacteriaceae (CPE) are an emerging threat in both solid organ and stem cell transplant recipients. Invasive CPE infections in transplant recipients are associated with a high mortality, often due to limited therapeutic options and antibacterial toxicities. One of the most therapeutically challenging group of CPE are the metallo-ß-lactamase (MBL)-producing Gram-negative bacteria, which are now found worldwide, and often need treatment with older, highly toxic antimicrobial regimens. Newer ß-lactamase inhibitors such as avibactam have well-established activity against certain carbapenemases such as Klebsiella pneumoniae carbapenemases (KPC), but have no activity against MBL-producing organisms. Conversely, aztreonam has activity against MBL-producing organisms but is often inactivated by other co-existing ß-lactamases. Here, we report four cases of invasive MBL-CPE infections in transplant recipients caused by IMP-4-producing Enterobacter cloacae who were successfully treated with a new, mechanism-driven antimicrobial combination of ceftazidime/avibactam with aztreonam. This novel antimicrobial combination offers a useful treatment option for high-risk patients with CPE infection, with reduced drug interactions and toxicity.


Assuntos
Compostos Azabicíclicos , Aztreonam , Ceftazidima , Infecções por Enterobacteriaceae , Humanos , Antibacterianos/uso terapêutico , Compostos Azabicíclicos/uso terapêutico , Aztreonam/uso terapêutico , Proteínas de Bactérias , beta-Lactamases , Ceftazidima/uso terapêutico , Combinação de Medicamentos , Enterobacter cloacae , Infecções por Enterobacteriaceae/tratamento farmacológico , Testes de Sensibilidade Microbiana , Transplantados
5.
Transgenic Res ; 29(3): 267-281, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32303980

RESUMO

Although genetic transformation of soybean dates back to over two decades, the process remains inefficient. Here, we report the development of an organogenesis-based transformation method of soybean that resulted in an average transformation frequency of 18.7%. This improved method resorts to Agrobacterium-mediated transformation of the split-seed explant with an attached partial embryonic axis obtained from an imbibed seed. In addition to the split-seed explant, Agrobacterium strain and preparation were shown to be important for improved transformation. Transformation with Agrobacterium tumefaciens EHA105 generated higher transformation frequencies and number of low copy events compared to the strain EHA101. In this system, phosphinothricin acetyl transferase conferring tolerance to glufosinate was successfully employed for efficiently producing transgenic events. Around 48% of the T1 progeny was demonstrated to be heritable based on molecular analysis and screening with the herbicide Liberty®. This method was shown to be applicable to different genotypes and a few elite lines showed high transformation frequencies. This split-seed system with an attached partial embryonic axis serves not only as an efficient means for high throughput transgenic production for basic research studies but also for the commercial development of transgenic soybean products.


Assuntos
Agrobacterium tumefaciens/genética , Regulação da Expressão Gênica de Plantas , Glycine max/genética , Plantas Geneticamente Modificadas/genética , Sementes/genética , Transformação Genética , Transgenes , Vetores Genéticos , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/microbiologia , Glycine max/crescimento & desenvolvimento , Glycine max/microbiologia
11.
J Strength Cond Res ; 31(8): 2131-2140, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27787466

RESUMO

Coker, NA, Wells, AJ, Ake, KM, Griffin, DL, Rossi, SJ, and McMillan, JL. Relationship between running performance and recovery-stress state in collegiate soccer players. J Strength Cond Res 31(8): 2131-2140, 2017-The purpose of this study was to evaluate the relationship between changes in running performance and the stress-recovery state in collegiate soccer players. Running performance was evaluated in 7 National Collegiate Athletic Association Division I male soccer players (179.39 ± 5.24 cm; 75.46 ± 5.98 kg; 20.37 ± 1.41 years) through global positioning systems over the course of 12 competitive games in a single season. The regular season was divided into 4 competitive blocks: B1 (n = 3), B2 (n = 3), B3 (n = 3), and B4 (n = 3). Total distance and distance covered while engaging in walking, jogging, low-speed running, high-speed running, sprinting, low-intensity running, and high-intensity running were assessed during each block. The Recovery-Stress Questionnaire (RESTQ) 52 Sport was administered twice during each block to evaluate measures of stress and recovery. Total distance was greater during B4 compared with B1 (p = 0.027). Jogging and low-speed running were greater during B4 compared with all other time points (p's ≤ 0.05). Low-intensity running distance was greater during B4 compared with B1 (p = 0.034). Sport-specific recovery decreased significantly during B4 compared with B1 (p = 0.035). Correlational analysis indicated that high-velocity running was associated with increased stress, whereas low-velocity running was associated with greater recovery. However, changes in sport-specific recovery did not correlate with changes in running performance from B1 to B4. Results of this study indicate that running performance decreased across the season. Changes in running performance coincided with a decrease in sport-specific recovery. Practitioners may benefit from including the RESTQ as part of an assessment battery to monitor the stress/recovery state of athletes.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Futebol/fisiologia , Sistemas de Informação Geográfica , Humanos , Masculino , Corrida/fisiologia
14.
Mol Microbiol ; 92(3): 440-52, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24589252

RESUMO

Colicins are a diverse family of large antibacterial protein toxins, secreted by and active against Escherichia coli and must cross their target cell's outer membrane barrier to kill. To achieve this, most colicins require an abundant porin (e.g. OmpF) plus a low-copy-number, high-affinity, outer membrane protein receptor (e.g. BtuB). Recently, genetic screens have suggested that colicin N (ColN), which has no high-affinity receptor, targets highly abundant lipopolysaccharide (LPS) instead. Here we reveal the details of this interaction and demonstrate that the ColN receptor-binding domain (ColN-R) binds to a specific region of LPS close to the membrane surface. Data from in vitro studies using calorimetry and both liquid- and solid-state NMR reveal the interactions behind the in vivo requirement for a defined oligosaccharide region of LPS. Delipidated LPS (LPS(Δ) (LIPID) ) shows weaker binding; and thus full affinity requires the lipid component. The site of LPS binding means that ColN will preferably bind at the interface and thus position itself close to the surface of its translocon component, OmpF. ColN is, currently, unique among colicins in requiring LPS and, combined with previous data, this implies that the ColN translocon is distinct from those of other known colicins.


Assuntos
Colicinas/metabolismo , Escherichia coli/metabolismo , Lipopolissacarídeos/metabolismo , Porinas/metabolismo , Calorimetria , Espectroscopia de Ressonância Magnética , Ligação Proteica
15.
Anesthesiology ; 123(2): 434-43, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26079801

RESUMO

BACKGROUND: Complications with IV patient-controlled analgesia include programming errors, invasive access, and impairment of mobility. This study evaluated an investigational sufentanil sublingual tablet system (SSTS) for the management of pain after knee or hip arthroplasty. METHODS: This prospective, randomized, parallel-arm, double-blind study randomized postoperative patients at 34 U.S. sites to receive SSTS 15 µg (n = 315) or an identical placebo system (n = 104) and pain scores were recorded for up to 72 h. Adult patients with American Society of Anesthesiologists status 1 to 3 after primary total unilateral knee or hip replacement under general anesthesia or with spinal anesthesia that did not include intrathecal opioids were eligible. Patients were excluded if they were opioid tolerant. The primary endpoint was the time-weighted summed pain intensity difference to baseline over 48 h. Secondary endpoints included total pain relief, patient and healthcare professional global assessments, and patient and nurse ease-of-care questionnaires. RESULTS: Summed pain intensity difference (standard error) was higher (better) in the SSTS group compared with placebo (76 [7] vs. -11 [11], difference 88 [95% CI, 66 to 109]; P < 0.001). In the SSTS group, more patients and nurses responded "good" or "excellent" on the global assessments compared with placebo (P < 0.001). Patient and nurse ease-of-care ratings for the system were high in both groups. There was a higher incidence of nausea and pruritus in the SSTS group. CONCLUSION: SSTS could be an effective patient-controlled pain management modality in patients after major orthopedic surgery and is easy to use by both patients and healthcare professionals.


Assuntos
Analgésicos Opioides/administração & dosagem , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Manejo da Dor/métodos , Dor Pós-Operatória/prevenção & controle , Sufentanil/administração & dosagem , Administração Sublingual , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/efeitos dos fármacos , Medição da Dor/métodos , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/etiologia , Estudos Prospectivos
16.
Gynecol Oncol ; 138(3): 513-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26171911

RESUMO

OBJECTIVES: Ang1 & 2 (angiopoietin-1; -2) interact with Tie2 receptors on endothelial cells to mediate vascular remodeling in an angiogenesis signaling pathway distinct from the VEGF axis. Trebananib is a peptide Fc fusion protein that binds Ang1 and 2 and prevents interaction with Tie2. The efficacy of trebananib in recurrent/persistent endometrial cancer (EC) was studied. METHODS: The primary objective was to determine the frequency of patients with objective tumor responses (ORR) and event-free survival for ≥6months (6-month EFS) and determine toxicity of trebananib at a dose and schedule of 15mg/kg, IV QW. Recurrent/persistent EC, measurable disease, and ≤2 prior chemotherapy lines were required. RESULTS: Thirty-two patients were eligible and treated. The most common histologies were G1/2 endometrioid (31%), G3 endometrioid (28%) and serous (31.3%). 78% of patients had 1 prior regimen. Patients received 1-9+ cycles of trebananib; 24 patients (75%) received ≤2cycles. One patient had a partial response (3.1%); 8 patients had stable disease (25%) and 5 patients (15.6%) had 6 month EFS. Median progression-free survival and overall-survival were 1.97 months (90% CI 1.77-2.1) and 6.6 months (90% CI 4.01-14.75), respectively. Most common adverse events (AEs) were fatigue, anemia, and GI issues. Grade 3 and 4 AEs were: GI 31 and 0%; vascular 22 and 0%; metabolism/nutrition 19 and 3%; and general (including edema) 16 and 0%. CONCLUSIONS: Trebananib has insufficient single agent activity in recurrent EC to warrant further investigation at this dose/schedule.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neoplasias do Endométrio/tratamento farmacológico , Proteínas Recombinantes de Fusão/uso terapêutico , Adulto , Idoso , Inibidores da Angiogênese/efeitos adversos , Angiopoietina-1/antagonistas & inibidores , Angiopoietina-1/metabolismo , Angiopoietina-2/antagonistas & inibidores , Angiopoietina-2/metabolismo , Neoplasias do Endométrio/irrigação sanguínea , Neoplasias do Endométrio/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Proteínas Recombinantes de Fusão/efeitos adversos
19.
Biochim Biophys Acta ; 1828(8): 1731-42, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23567915

RESUMO

Lipopolysaccharide (LPS) is a major component of the external leaflet of bacterial outer membranes, key pro-inflammatory factor and an important mediator of host-pathogen interactions. In host cells it activates the complement along with a pro-inflammatory response via a TLR4-mediated signalling cascade and shows preference for cholesterol-containing membranes. Here, we use solid state (13)C and (31)P MAS NMR to investigate the interactions of LPS from three bacterial species, Brucella melitensis, Klebsiella pneumoniae and Escherichia coli, with mixed lipid membranes, raft models. All endotoxin types are found to be pyrophosphorylated and Klebsiellar LPS is phosphonylated, as well. Carbon-13 MAS NMR indicates an increase in lipid order in the presence of LPS. Longitudinal (31)P relaxation, providing a direct probe of LPS molecular and segmental mobility, reveals a significant reduction in (31)P T1 times and lower molecular mobility in the presence of ternary lipid mixtures. Along with the ordering effect on membrane lipid, this suggests a preferential partitioning of LPS into ordered bilayer sphingomyelin/cholesterol-rich domains. We hypothesise that this is an important evolutionary drive for the selection of GPI-anchored raft-associated LPS-binding proteins as a first line of response to membrane-associated LPS.


Assuntos
Membrana Celular/metabolismo , Bicamadas Lipídicas/metabolismo , Lipopolissacarídeos/metabolismo , Espectroscopia de Ressonância Magnética , Lipídeos de Membrana/metabolismo , Microdomínios da Membrana/metabolismo , Fosfolipídeos/metabolismo , Brucella melitensis/fisiologia , Escherichia coli/fisiologia , Interações Hospedeiro-Patógeno , Klebsiella pneumoniae/fisiologia , Modelos Moleculares
20.
Soft Matter ; 10(12): 1905-16, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24652367

RESUMO

Polymer networks are critically important for numerous applications including soft biomaterials, adhesives, coatings, elastomers, and gel-based materials for energy storage. One long-standing challenge these materials present lies in understanding the role of network defects, such as dangling ends and loops, developed during cross-linking. These defects can negatively impact the physical, mechanical, and transport properties of the gel. Here we report chemically cross-linked poly(ethylene glycol) (PEG) gels formed through a unique cross-linking scheme designed to minimize defects in the network. The highly resilient mechanical properties of these systems (discussed in a previous publication) [J. Cui, M. A. Lackey, A. E. Madkour, E. M. Saffer, D. M. Griffin, S. R. Bhatia, A. J. Crosby and G. N. Tew, Biomacromolecules, 2012, 13, 584-588], suggests that this cross-linking technique yields more homogeneous network structures. Four series of gels were formed based on chains of 35,000 g mol(-1), (35k), 12,000 g mol(-1) (12k) g mol(-1), 8000 g mol(-1) (8k) and 4000 g mol(-1) (4k) PEG. Gels were synthesized at five initial polymer concentrations ranging from 0.077 g mL(-1) to 0.50 g mL(-1). Small-angle neutron scattering (SANS) was utilized to investigate the network structures of gels in both D2O and d-DMF. SANS results show the resulting network structure is dependent on PEG length, transitioning from a more homogeneous network structure at high molecular weight PEG to a two phase structure at the lowest molecular weight PEG. Further investigation of the transport properties inherent to these systems, such as diffusion, will aid to further confirm the network structures.


Assuntos
Hidrogéis/química , Polietilenoglicóis/química , Espalhamento a Baixo Ângulo , Materiais Biocompatíveis , Difração de Nêutrons , Polímeros/química
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