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1.
J Biol Chem ; 299(2): 102889, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36634847

RESUMO

Osteoporosis is a chronic skeletal condition characterized by low bone mass and deteriorated microarchitecture of bone tissue and puts tens of millions of people at high risk of fractures. New therapeutic agents like i-bodies, a class of next-generation single-domain antibodies, are needed to overcome some limitations of conventional treatments. An i-body is a human immunoglobulin scaffold with two long binding loops that mimic the shape and position of those found in shark antibodies, the variable new antigen receptors of sharks. Its small size (∼12 kDa) and long binding loops provide access to drug targets, which are considered undruggable by traditional monoclonal antibodies. Here, we have successfully identified a human receptor activator of nuclear factor-κB ligand (RANKL) i-body, ADR3, which demonstrates a high binding affinity to human RANKL (hRANKL) with no adverse effect on the survival or proliferation of bone marrow-derived macrophages. Differential scanning fluorimetry suggested that ADR3 is stable and able to tolerate a wide range of physical environments (including both temperature and pH). In addition, in vitro studies showed a dose-dependent inhibitory effect of ADR3 on osteoclast differentiation, podosome belt formation, and bone resorption activity. Further investigation on the mechanism of action of ADR3 revealed that it can inhibit hRANKL-mediated signaling pathways, supporting the in vitro functional observations. These clues collectively indicate that hRANKL antagonist ADR3 attenuates osteoclast differentiation and bone resorption, with the potential to serve as a novel therapeutic to protect against bone loss.


Assuntos
Reabsorção Óssea , Osteoclastos , Ligante RANK , Anticorpos de Domínio Único , Humanos , Reabsorção Óssea/genética , Reabsorção Óssea/metabolismo , Diferenciação Celular/genética , Macrófagos/citologia , Macrófagos/metabolismo , Osteoclastos/citologia , Ligante RANK/metabolismo , Transdução de Sinais , Anticorpos de Domínio Único/metabolismo
2.
J Pediatr Orthop ; 44(5): 322-326, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38389197

RESUMO

BACKGROUND: The lower extremity functional scale (LEFS) is a patient-reported outcome measure for assessment of lower extremity function. It has been validated in adults but not in children or adolescents. METHODS: Patients 8 to 18 years of age who were treated for a lower limb fracture, injury, or other conditions were invited to join the study. LEFS and Pediatric Quality of Life Inventory 4.0 Generic Core Scales (PedsQL) were administered. Reliability and validity of the LEFS were determined for the entire cohort and for 2 age groups (children: 8 to 12 years; adolescents 13 to 18 years) using PedsQL as comparison. RESULTS: A total of 178 patients were recruited into this study. In the entire cohort, internal consistency of LEFS was excellent (0. 972) with acceptable floor (0%) and ceiling (12%) effects. Correlation between LEFS and PedsQL physical functioning component was high ( r =0.859). Construct validity was acceptable, with all 8 hypotheses demonstrating statistical significance. Factor analysis showed that item 15 (sitting for 1 hour) may contribute to measurement error in the pediatric population. Results remained similar when comparing the 2 age groups. CONCLUSIONS: The LEFS is overall an acceptable patient-reported outcome assessment of children and adolescents with various lower limbs disorders. LEVEL OF EVIDENCE: Level II.


Assuntos
Avaliação da Deficiência , Qualidade de Vida , Adulto , Humanos , Criança , Adolescente , Reprodutibilidade dos Testes , Extremidade Inferior , Medidas de Resultados Relatados pelo Paciente , Psicometria/métodos , Inquéritos e Questionários
3.
J Pediatr Orthop ; 44(3): 157-163, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37994645

RESUMO

BACKGROUND: Cast immobilization is the mainstay of treatment for stable pediatric supracondylar humeral fractures (SCHFs). In recent years, a waterproof and breathable hybrid-mesh (HM) cast has emerged and been marketed to address common complaints such as itch, skin irritation, and malodor. Hence, this randomized controlled trial seeks to assess the overall satisfaction, comfort, and clinical outcomes of using HM casts in the conservative treatment of stable pediatric SCHF. METHODS: Seventy-nine patients (age range: 1 to 10 y) with modified Gartland's classification Type I and Type IIa SCHF were recruited and randomized for immobilization with either fiberglass or HM long-arm cast for 3 weeks. During follow-up visits, patients were assessed for any loss of reduction and skin rash. The weight of casts, the presence of cast breakage, the duration of cast application, and removal were recorded. A self-reported patient comfort and satisfaction questionnaire was also administered during the same visit. RESULTS: The final analysis included 38 patients immobilized with fiberglass casts and 39 patients with HM casts. Despite the significantly longer duration required for HM cast removal (4.18±1.25 min vs. 2.25±0.55 min, P <0.001), the HM cast was significantly lighter than its fiberglass counterpart (162.82±23.94 g vs. 203.95±36.52 g, P <0.001). The HM casts have better comfort (4.05±0.887 vs. 3.47±0.951, P =0.007) and satisfaction (3.69±1.055 vs. 3.11±0.953, P =0.012) scores as compared to fiberglass casts for immobilizing pediatric SCHF without compromising clinical outcome. CONCLUSIONS: HM casts have better comfort and overall satisfaction as compared to conventional fiberglass casts for immobilizing pediatric SCHF without compromising clinical outcomes. LEVEL OF EVIDENCE: Level II-therapeutic studies-investigating the results of treatment.


Assuntos
Moldes Cirúrgicos , Fraturas do Úmero , Criança , Pré-Escolar , Humanos , Lactente , Tratamento Conservador , Próteses e Implantes
4.
Eur J Orthop Surg Traumatol ; 34(4): 1803-1809, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38416233

RESUMO

PURPOSE: Bracing for adolescents with idiopathic scoliosis (AIS) is a treatment option to prevent curve progression to surgical level. This study aimed to assess the efficacy of a 3D fully customized over corrective brace, "ScoliBrace," an orthosis treatment for AIS. METHODS: This was a prospective pilot study of AIS female patients with inclusion criteria followed recommended Scoliosis Research Society (SRS) Guidelines. Cobb angles measured at: baseline (T0), 21 months (T5-2), skeletal maturity (T6), 6 months post-brace (T7), along with hours of brace wear using a thermal sensor and health-related quality of life (HRQoL) using the SRS-22r questionnaire. RESULTS: A total of 30 female AIS patients with mean age 11.85 ± 0.68 years, predominantly Risser 0 (70%), and median Cobb angle 29° were recruited; 21 patients were included for the final analysis. Results showed significant difference in Cobb angle between T0 and T5-2 (median = 22.5° vs. 28.5°, p = 0.0082). 57.14% had reduction in Cobb angle by ≥ 5° at skeletal maturity. Cobb angle reduced 0.794° for each additional hour of dosage (p = 0.036, 95% CI = - 1.532°, - 0.056°). Although pain level was increased at T6 (4.37 ± 0.51vs.4.70 ± 0.41, p = 0.014), patients reported significantly greater satisfaction with management of their condition (3.90 ± 0.90vs.3.29 ± 0.88, p = 0.020). CONCLUSION: Results show similar findings to the BRAIST study, whereby curves remained under surgical threshold and showed improvement. More than half had curve reduction of ≥ 5° at skeletal maturity. Increased dose was also associated with improved outcomes. Using "ScoliBrace" as a non-surgical treatment, maintained curves below surgical threshold and showed curve reduction, improving patient satisfaction with management.


Assuntos
Braquetes , Qualidade de Vida , Escoliose , Humanos , Escoliose/terapia , Feminino , Projetos Piloto , Estudos Prospectivos , Criança , Adolescente , Resultado do Tratamento , Satisfação do Paciente
5.
Eur Spine J ; 32(11): 3987-3995, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37428212

RESUMO

PURPOSE: To determine if the novel 3D Machine-Vision Image Guided Surgery (MvIGS) (FLASH™) system can reduce intraoperative radiation exposure, while improving surgical outcomes when compared to 2D fluoroscopic navigation. METHODS: Clinical and radiographic records of 128 patients (≤ 18 years of age) who underwent posterior spinal fusion (PSF), utilising either MvIGS or 2D fluoroscopy, for severe idiopathic scoliosis were retrospectively reviewed. Operative time was analysed using the cumulative sum (CUSUM) method to evaluate the learning curve for MvIGS. RESULTS: Between 2017 and 2021, 64 patients underwent PSF using pedicle screws with 2D fluoroscopy and another 64 with the MvIGS. Age, gender, BMI, and scoliosis aetiology were comparable between the two groups. The CUSUM method estimated that the MvIGS learning curve with respect to operative time was 9 cases. This curve consisted of 2 phases: Phase 1 comprises the first 9 cases and Phase 2 the remaining 55 cases. Compared to 2D fluoroscopy, MvIGS reduced intraoperative fluoroscopy time, radiation exposure, estimated blood loss and length of stay by 53%, 62% 44%, and 21% respectively. Scoliosis curve correction was 4% higher in the MvIGS group, without any increase in operative time. CONCLUSION: MvIGS for screw insertion in PSF contributed to a significant reduction in intraoperative radiation exposure and fluoroscopy time, as well as blood loss and length of stay. The real-time feedback and ability to visualize the pedicle in 3D with MvIGS enabled greater curve correction without increasing the operative time.


Assuntos
Parafusos Pediculares , Escoliose , Fusão Vertebral , Cirurgia Assistida por Computador , Humanos , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Estudos Retrospectivos , Perda Sanguínea Cirúrgica/prevenção & controle , Fusão Vertebral/métodos , Fluoroscopia/métodos , Cirurgia Assistida por Computador/métodos , Radiação Ionizante
6.
Int J Mol Sci ; 24(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36674774

RESUMO

We report enzymes from the berberine bridge enzyme (BBE) superfamily that catalyze the oxidative cyclization of the monoterpene moiety in cannabigerolic acid (CBGA) to form cannabielsoin (CBE). The enzymes are from a variety of organisms and are previously uncharacterized. Out of 232 homologues chosen from the enzyme superfamily, four orthologues were shown to accept CBGA as a substrate and catalyze the biosynthesis of CBE. The four enzymes discovered in this study were recombinantly expressed and purified in Pichia pastoris. These enzymes are the first report of heterologous expression of BBEs that did not originate from the Cannabis plant that catalyze the production of cannabinoids using CBGA as substrate. This study details a new avenue for discovering and producing natural and unnatural cannabinoids.


Assuntos
Canabinoides , Cannabis , Canabinoides/metabolismo , Cannabis/genética , Cannabis/química , Oxirredução , Catálise , Óxido Nítrico Sintase/metabolismo
7.
J Card Surg ; 37(11): 3634-3638, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36054404

RESUMO

BACKGROUND: Novel clinical challenges are faced by cardiac surgeons under the coronavirus disease 2019 (COVID-19) pandemic. Amidst the uncertainties faced due to the socioeconomic and public health impact, there is little evidence surrounding COVID-19 vaccination in patients undergoing cardiac surgery. Timing of vaccination and postvaccination adverse effects are required parameters to discuss with cardiac surgical patients. METHODS: This is a single-center, retrospective observational study. All patients who underwent adult cardiac surgery at the Prince of Wales Hospital, Hong Kong from January 2021 to December 2021 were included. Postoperative clinical outcomes, COVID-19 vaccination status, and vaccination-related adverse effects were collected. RESULTS: A total of 426 patients; 117 (27%) underwent isolated coronary artery bypass grafting, 111 (26%) underwent valvular surgery, and 97 (23%) underwent aortic surgery. Patients received either Sinovac CoronaVac or Pfizer BNT162b2 vaccine. Overall vaccination rate with at least 1 dose was 52% (n = 212), 15% (n = 63) received the first dose before surgery, 36% (n = 149) received the first dose vaccination after surgery. Rate of completion with second and third doses of vaccination were 22% (n = 89) and 4.9% (n = 20), respectively. The mean timing of first dose of vaccine after surgery was 216 ± 84 days from operation. Three (1.4%) patients recorded vaccination-related complications. CONCLUSIONS: COVID-19 vaccination is safe in patients who received major cardiac surgery, with low adverse effects recorded and no vaccine-related mortality observed. A time frame of 3-6 months after cardiac surgery receiving COVID-19 vaccination is reasonable and could serve as a guidance for future COVID-19 vaccination booster programs.


Assuntos
COVID-19 , Procedimentos Cirúrgicos Cardíacos , Adulto , Vacina BNT162 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Estudos Retrospectivos , Vacinação
8.
Nano Lett ; 21(11): 4721-4729, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34019769

RESUMO

Sculpting nanostructures into different geometries in either one or two dimensions produces a wide range of colorful elements in microscopic prints. However, achieving different shades of gray and control of color saturation remain challenging. Here, we report a complete approach to color and grayscale generation based on the tuning of a single nanostructure geometry. Through two-photon polymerization lithography, we systematically investigated color generation from the basic single nanopillar geometry in low-refractive-index (n < 1.6) material. Grayscale and full color palettes were achieved that allow decomposition onto hue, saturation, and brightness values. This approach enabled the "painting" of arbitrary colorful and grayscale images by mapping desired prints to precisely controllable parameters during 3D printing. We further extend our understanding of the scattering properties of the low-refractive-index nanopillar to demonstrate grayscale inversion and color desaturation and steganography at the level of single nanopillars.

9.
Gynecol Oncol ; 162(3): 686-693, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34275654

RESUMO

INTRODUCTION: Lynch syndrome is a multi-tumor syndrome characterized by mismatch repair deficiency (MMR-d), microsatellite instability (MSI), and increased tumor-infiltrating lymphocytes (TILs) making these tumors candidates for treatment with immune checkpoint inhibitors. However, response may depend on tumor-induced immune evasion mechanisms, e.g. loss of Beta-2-Microglobulin (B2M) or upregulation of programmed death protein ligand 1 (PD-L1). We investigated the immune response and B2M and PD-L1 expression in Lynch syndrome-associated ovarian cancers. METHODS: We successfully analyzed 30 Lynch syndrome-associated epithelial ovarian cancers collected through the Danish Hereditary Non-Polyposis Colorectal Cancer (HNPCC) register. MMR-d, MSI, immune response (CD3, CD8, and CD68), and immune evasion mechanisms (B2M and PD-L1) were investigated. Statistical associations between these markers were evaluated in addition to survival in relation to B2M/PD-L1. RESULTS: Of the 29 evaluable tumors, 27 were MMR-d (93.1%). Likewise of 26 evaluable tumors, 14 were MSI (53.8%). MMR-d/MMR-proficiency associated with MSI/MSS in 60.0%. Half of the ovarian tumors presented with high levels of TILs. Loss of B2M expression was observed in 46.7% of the tumors, while expression of PD-L1 was seen in 28.0% of the cases. There was no association between B2M/PD-L1 and MSI/TILs/survival. Loss of B2M was often seen in tumors with low TILs (p = 0.056 or p = 0.059 for CD3 and CD8 positive cells, respectively). CONCLUSION: MMR-d, MSI, and TILs are also seen in Lynch syndrome-associated ovarian cancers making these potential candidates for checkpoint-based immunotherapy. The clinical impact from immune evasion through loss of B2M needs to be investigated further in larger cohorts.


Assuntos
Carcinoma Epitelial do Ovário/imunologia , Neoplasias Colorretais Hereditárias sem Polipose/imunologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/imunologia , Adulto , Idoso , Antígeno B7-H1/imunologia , Carcinoma Epitelial do Ovário/genética , Carcinoma Epitelial do Ovário/patologia , Estudos de Coortes , Neoplasias Colorretais Hereditárias sem Polipose/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Humanos , Imunoterapia , Linfócitos do Interstício Tumoral/imunologia , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Sistema de Registros , Microglobulina beta-2/imunologia
10.
Support Care Cancer ; 29(6): 3319-3328, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33118105

RESUMO

PURPOSE: This study sought to investigate the prevalence of self-reported cognitive impairment and its relation to illness and treatment characteristics and mental health in Hodgkin lymphoma (HL) and diffuse large B cell lymphoma (DLBCL) survivors as cancer-related cognitive impairment has not been extensively studied in lymphoma survivors. METHODS: One hundred fifteen HL and DLBCL survivors (mean age = 40.3 years, mean months since completed treatment = 29.6) completed questionnaires on executive function and mental health. We examined the prevalence of executive impairment and compared illness and treatment characteristics and mental health across survivors reporting impaired and non-impaired executive functioning using chi-square, Cochran-Armitage, and Mann-Whitney U tests. RESULTS: We found that 39% reported executive impairment. Survivors reporting impaired executive functioning reported worse mental health (ps < .001) than survivors reporting non-impaired executive functioning. A larger proportion of the impaired group had received a high chemo dose compared to the non-impaired group although this result fell short of significance after adjustment for multiple comparisons (p = .017). CONCLUSIONS: Self-reported cognitive impairment is prevalent in HL and DLBCL survivors and is associated with worse mental health and possibly high chemo dose. Future studies should investigate objective impairment and the possible dose-response relationship between chemo dose and cognitive impairment in lymphoma survivors.


Assuntos
Disfunção Cognitiva/etiologia , Disfunção Cognitiva/psicologia , Função Executiva/fisiologia , Doença de Hodgkin/complicações , Doença de Hodgkin/psicologia , Saúde Mental/normas , Adulto , Sobreviventes de Câncer , Dinamarca , Feminino , Doença de Hodgkin/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
11.
BMC Pediatr ; 21(1): 568, 2021 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-34895166

RESUMO

BACKGROUND: Osteomyelitis in immunocompromised children can present differently from immunocompetent children and can cause devastating sequelae if treated inadequately. We aim to review the aetiology, clinical profile, treatment and outcomes of immunocompromised children with osteomyelitis. METHODS: Retrospective review of all immunocompromised children aged < 16 years and neonates admitted with osteomyelitis in our hospital between January 2000 and January 2017, and referred to the Paediatric Infectious Disease Service. RESULTS: Fourteen patients were identified. There were 10 boys (71%), and the median age at admission was 70.5 months (inter-quartile range: 12.3-135.0 months). Causal organisms included, two were Staphylococcus aureus, two were Mycobacterium bovis (BCG), and one each was Mycobacterium tuberculosis, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Burkholderia pseudomallei and Rhizopus sp. One patient had both Clostridium tertium and Clostridium difficile isolated. Treatment involved appropriate antimicrobials for a duration ranging from 6 weeks to 1 year, and surgery in 11 patients (79%). Wherever possible, the patients received treatment for their underlying immunodeficiency. For outcomes, only three patients (21%) recovered completely. Five patients (36%) had poor bone growth, one patient had recurrent discharge from the bone and one patient had palliative care for underlying osteosarcoma. CONCLUSIONS: Although uncommon, osteomyelitis in immunocompromised children and neonates can be caused by unusual pathogens, and can occur with devastating effects. Treatment involves prolonged administration of antibiotics and surgery. Immune recovery also seems to be an important factor in bone healing.


Assuntos
Mycobacterium bovis , Mycobacterium tuberculosis , Osteomielite , Antibacterianos/uso terapêutico , Criança , Humanos , Recém-Nascido , Masculino , Osteomielite/diagnóstico , Osteomielite/tratamento farmacológico , Estudos Retrospectivos
12.
J Card Surg ; 36(9): 3112-3118, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34137081

RESUMO

BACKGROUND: Despite significant advancements in operative techniques and myocardial protection, triple valve surgery (TVS) remains a formidable operation with a relatively high in-hospital mortality. We evaluated the prognostic value of Model for End-stage Liver Disease score including sodium (MELD-Na) for mortality after TVS and its predictive value when incorporated in the EuroSCORE risk model. METHODS: We performed a retrospective cohort study of 61 consecutive patients who underwent TVS from November 2005 to June 2016. Demographics, clinical, biochemical, and operative data were collected and analyzed. RESULTS: Median follow-up duration was 8.0 years. The majority (70.5%) of patients suffered from rheumatic heart disease and underwent mechanical double valve replacement with tricuspid valve repair. There were six operative deaths (9.84%), with the most common cause of death being multiorgan failure (83.3%). In 26.2% of the cohort, the MELD-Na score was moderately elevated at 9 to 15. A small fraction (4.9%) had a severely elevated MELD-Na greater than 15. Patients with a MELD-Na greater than 9 had a higher unadjusted rate of operative mortality, prolonged ventilation, need for dialysis and acute liver failure after TVS. Hierarchical logistic regression was performed using logistic EuroSCORE as the base model. After risk adjustment, each point of MELD-Na score increase was associated with 1.405 times increase in odds of operative mortality. The regression analysis was repeated by incorporating individual components of the MELD-Na score, including bilirubin, sodium, and albumin. All three biochemical parameters were significantly associated with operative mortality CONCLUSION: MELD-Na score as a quantifier of hepatorenal dysfunction is sensitive and specific for operative mortality after triple valve surgery.


Assuntos
Doença Hepática Terminal , Humanos , Prognóstico , Diálise Renal , Estudos Retrospectivos , Índice de Gravidade de Doença , Sódio
13.
J Card Surg ; 36(3): 841-847, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33522638

RESUMO

BACKGROUND AND AIM: The Valiant NavionTM stent graft system is a third-generation low profile thoracic endograft designed for thoracic endovascular aortic repair. In this population analysis, we report on the first Asian all-comers experience and outcomes who underwent thoracic endovascular aortic repair with the use of this new stent graft system. METHODS: Between May 2019 and October 2020, 21 patients with different aortic pathologies were prospectively recruited and retrospectively analyzed. Important clinical and device-related outcomes were evaluated. The endpoints included short-term survival, technical success, access failures, major vascular and clinical complications, endoleaks, and hospital stay. RESULTS: The commonest indication of stenting was penetrating aortic ulcers (28.6%) and six (28.6%) patients had emergency stenting performed for aortic transection or rupture. 30 days of survival postprocedure was recorded and complete. There were no major vascular complications. Deployment accuracy was 100%, and the technical success rate was 94.7% (18/19) with one patient having a Type 2 endoleak on follow-up imaging. No neurological complications were noted. The mean operative time was 95 ± 73.6 min and the mean fluoroscopy time was 16.2 ± 10.8 min. Mean hospital stay for elective zone 2, 3, and 4 stenting was 5.3 ± 3.8 days, and only one patient postzone 1 thoracic endovascular aortic repair required a brief (0.5 days) ICU stay. All procedures were performed via the percutaneous transfemoral route with 100% success in percutaneous closure. CONCLUSION: This first reported Asian case series demonstrated versatility, safety, and efficacy of the Valiant NavionTM stent in Asian patients with different aortic pathologies.


Assuntos
Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Procedimentos Endovasculares , Aneurisma da Aorta Torácica/cirurgia , Prótese Vascular , Humanos , Desenho de Prótese , Estudos Retrospectivos , Stents , Resultado do Tratamento
14.
Molecules ; 26(10)2021 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-34068935

RESUMO

Natural products make up a large proportion of medicine available today. Cannabinoids from the plant Cannabis sativa is one unique class of meroterpenoids that have shown a wide range of bioactivities and recently seen significant developments in their status as therapeutic agents for various indications. Their complex chemical structures make it difficult to chemically synthesize them in efficient yields. Synthetic biology has presented a solution to this through metabolic engineering in heterologous hosts. Through genetic manipulation, rare phytocannabinoids that are produced in low yields in the plant can now be synthesized in larger quantities for therapeutic and commercial use. Additionally, an exciting avenue of exploring new chemical spaces is made available as novel derivatized compounds can be produced and investigated for their bioactivities. In this review, we summarized the biosynthetic pathways of phytocannabinoids and synthetic biology efforts in producing them in heterologous hosts. Detailed mechanistic insights are discussed in each part of the pathway in order to explore strategies for creating novel cannabinoids. Lastly, we discussed studies conducted on biological targets such as CB1, CB2 and orphan receptors along with their affinities to these cannabinoid ligands with a view to inform upstream diversification efforts.


Assuntos
Canabinoides/biossíntese , Vias Biossintéticas , Canabinoides/química , Cannabis/química , Dimetilaliltranstransferase/metabolismo , Engenharia de Proteínas , Receptores de Canabinoides/metabolismo
15.
Gut ; 69(6): 1039-1052, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31542774

RESUMO

OBJECTIVE: Genomic structural variations (SVs) causing rewiring of cis-regulatory elements remain largely unexplored in gastric cancer (GC). To identify SVs affecting enhancer elements in GC (enhancer-based SVs), we integrated epigenomic enhancer profiles revealed by paired-end H3K27ac ChIP-sequencing from primary GCs with tumour whole-genome sequencing (WGS) data (PeNChIP-seq/WGS). DESIGN: We applied PeNChIP-seq to 11 primary GCs and matched normal tissues combined with WGS profiles of >200 GCs. Epigenome profiles were analysed alongside matched RNA-seq data to identify tumour-associated enhancer-based SVs with altered cancer transcription. Functional validation of candidate enhancer-based SVs was performed using CRISPR/Cas9 genome editing, chromosome conformation capture assays (4C-seq, Capture-C) and Hi-C analysis of primary GCs. RESULTS: PeNChIP-seq/WGS revealed ~150 enhancer-based SVs in GC. The majority (63%) of SVs linked to target gene deregulation were associated with increased tumour expression. Enhancer-based SVs targeting CCNE1, a key driver of therapy resistance, occurred in 8% of patients frequently juxtaposing diverse distal enhancers to CCNE1 proximal regions. CCNE1-rearranged GCs were associated with high CCNE1 expression, disrupted CCNE1 topologically associating domain (TAD) boundaries, and novel TAD interactions in CCNE1-rearranged primary tumours. We also observed IGF2 enhancer-based SVs, previously noted in colorectal cancer, highlighting a common non-coding genetic driver alteration in gastric and colorectal malignancies. CONCLUSION: Integrated paired-end NanoChIP-seq and WGS of gastric tumours reveals tumour-associated regulatory SV in regions associated with both simple and complex genomic rearrangements. Genomic rearrangements may thus exploit enhancer-hijacking as a common mechanism to drive oncogene expression in GC.


Assuntos
Adenocarcinoma/metabolismo , Ciclina E/metabolismo , Elementos Facilitadores Genéticos/genética , Fator de Crescimento Insulin-Like II/metabolismo , Proteínas Oncogênicas/metabolismo , Neoplasias Gástricas/metabolismo , Adenocarcinoma/genética , Variação Estrutural do Genoma/genética , Humanos , Neoplasias Gástricas/genética , Sequenciamento Completo do Genoma
16.
Appl Environ Microbiol ; 87(1)2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33097506

RESUMO

The lactobacilli identified to date encompass more than 270 closely related species that were recently reclassified into 26 genera. Because of their relevance to industry, there is a need to distinguish between closely related and yet metabolically and regulatory distinct species, e.g., during monitoring of biotechnological processes or screening of samples of unknown composition. Current available methods, such as shotgun metagenomics or rRNA gene-based amplicon sequencing, have significant limitations (high cost, low resolution, etc.). Here, we generated a phylogeny of lactobacilli based on phenylalanyl-tRNA synthetase (pheS) genes and, from it, developed a high-resolution taxonomic framework which allows for comprehensive and confident characterization of the community diversity and structure of lactobacilli at the species level. This framework is based on a total of 445 pheS gene sequences, including sequences of 276 validly described species and subspecies (of a total of 282, including the proposed L. timonensis species and the reproposed L. zeae species; coverage of 98%), and allows differentiation between 265 species-level clades of lactobacilli and the subspecies of L. sakei The methodology was validated through next-generation sequencing of mock communities. At a sequencing depth of ∼30,000 sequences, the minimum level of detection was approximately 0.02 pg per µl DNA (equaling approximately 10 genome copies per µl template DNA). The pheS approach, along with parallel sequencing of partial 16S rRNA genes, revealed considerable diversity of lactobacilli and distinct community structures across a broad range of samples from different environmental niches. This novel complementary approach may be applicable to industry and academia alike.IMPORTANCE Species formerly classified within the genera Lactobacillus and Pediococcus have been studied extensively at the genomic level. To accommodate their exceptional functional diversity, the over 270 species were recently reclassified into 26 distinct genera. Despite their relevance to both academia and industry, methods that allow detailed exploration of their ecology are still limited by low resolution, high cost, or copy number variations. The approach described here makes use of a single-copy marker gene which outperforms other markers with regard to species-level resolution and availability of reference sequences (98% coverage). The tool was validated against a mock community and used to address diversity of lactobacilli and community structure in various environmental matrices. Such analyses can now be performed at a broader scale to assess and monitor the assembly, structure, and function of communities of lactobacilli at the species level (and, in some cases, even at the subspecies level) across a wide range of academic and commercial applications.


Assuntos
Genes Bacterianos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Lactobacillus/genética , Microbiota/genética , Pediococcus/genética , Fenilalanina-tRNA Ligase/genética , Lactobacillus/classificação , Lactobacillus/enzimologia , Pediococcus/classificação , Pediococcus/enzimologia
17.
BMC Public Health ; 20(1): 648, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32393222

RESUMO

BACKGROUND: There is a paucity of information on the epidemiology of heart failure (HF) in Australia. The Study of Heart failure in the Australian Primary carE setting (SHAPE) study aims to estimate the prevalence and annual incidence of HF in the general Australian community and to describe the demographic and key clinical profile of Australians with HF. METHODS: We undertook a retrospective cohort study based on analysis of non-identifiable medical records of adult patients cared for at 43 general practices between 1 July 2013 and 30 June 2018. Data were extracted from coded (diagnosis, pathology and prescription fields) and uncoded fields (clinical notes) in the medical records. The latter searches of free text looked for common synonyms relevant to HF. The population was stratified into three groups based on a hierarchy of selection criteria: (1) definite HF, (2) probable HF and (3) possible HF. The prevalence and annual incidence of HF were calculated, along with 95% confidence intervals. RESULTS: The practices provided care to 2.3 million individual patients over the five-year study period, of whom 1.93 million were adults and 1.12 million were regular patients. Of these patients 15,468 were classified as having 'definite HF', 4751 as having 'probable HF' and 33,556 as having 'possible HF'. A further 39,247 were identified as having an aetiological condition associated with HF. A formal HF diagnosis, HF terms recorded as text in the notes and HF-specific medication were the most common methods to identify 'definite' HF patients. Typical signs and symptoms in combination with a diuretic prescription was the most common method to identify 'probable HF' patients. The majority of 'possible' HF patients were identified by the presence of 2 or more of the typical signs or symptoms. Dyspnoea was the commonest recorded symptom and an elevated jugular venous pressure the commonest recorded sign. CONCLUSIONS: This novel approach to undertaking retrospective research of primary care data successfully analysed a combination of coded and uncoded data from the electronic medical records of patients routinely managed in the GP setting. SHAPE is the first real-world study of the epidemiology of HF in the general Australian community setting.


Assuntos
Medicina Geral/estatística & dados numéricos , Insuficiência Cardíaca/epidemiologia , Atenção Primária à Saúde/estatística & dados numéricos , Adulto , Idoso , Austrália/epidemiologia , Registros Eletrônicos de Saúde , Feminino , Insuficiência Cardíaca/etiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Adulto Jovem
19.
J Biol Chem ; 291(24): 12641-12657, 2016 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-27036939

RESUMO

CXCR4 is a G protein-coupled receptor with excellent potential as a therapeutic target for a range of clinical conditions, including stem cell mobilization, cancer prognosis and treatment, fibrosis therapy, and HIV infection. We report here the development of a fully human single-domain antibody-like scaffold termed an "i-body," the engineering of which produces an i-body library possessing a long complementarity determining region binding loop, and the isolation and characterization of a panel of i-bodies with activity against human CXCR4. The CXCR4-specific i-bodies show antagonistic activity in a range of in vitro and in vivo assays, including inhibition of HIV infection, cell migration, and leukocyte recruitment but, importantly, not the mobilization of hematopoietic stem cells. Epitope mapping of the three CXCR4 i-bodies AM3-114, AM4-272, and AM3-523 revealed binding deep in the binding pocket of the receptor.


Assuntos
Receptores CXCR4/antagonistas & inibidores , Receptores CXCR4/imunologia , Anticorpos de Domínio Único/imunologia , Anticorpos de Domínio Único/farmacologia , Animais , Especificidade de Anticorpos/imunologia , Sítios de Ligação/imunologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/imunologia , Células Cultivadas , Cristalografia por Raios X , Mapeamento de Epitopos , Células HEK293 , Infecções por HIV/imunologia , Infecções por HIV/prevenção & controle , Células HL-60 , Humanos , Células Jurkat , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Modelos Moleculares , Ligação Proteica/imunologia , Domínios Proteicos , Receptores CXCR4/metabolismo , Anticorpos de Domínio Único/química , Ressonância de Plasmônio de Superfície
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