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1.
PLoS One ; 19(7): e0302186, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38968185

RESUMO

INTRODUCTION: Minor amputation is commonly needed to treat diabetes-related foot disease (DFD). Remoteness of residence is known to limit access to healthcare and has previously been associated with poor outcomes. The primary aim of this study was to examine the associations between ethnicity and remoteness of residency with the risk of major amputation and death following initial treatment of DFD by minor amputation. A secondary aim was to identify risk factors for major amputation and death following minor amputation to treat DFD. RESEARCH DESIGN AND METHODS: This was a retrospective analysis of data from patients who required a minor amputation to treat DFD between 2000 and 2019 at a regional tertiary hospital in Queensland, Australia. Baseline characteristics were collected together with remoteness of residence and ethnicity. Remoteness was classified according to the 2019 Modified Monash Model (MMM) system. Ethnicity was based on self-identification as an Aboriginal and Torres Strait Islander or non-Indigenous person. The outcomes of major amputation, repeat minor amputation and death were examined using Cox-proportional hazard analyses. RESULTS: A total of 534 participants were included, with 306 (57.3%) residing in metropolitan or regional centres, 228 (42.7%) in rural and remote communities and 144 (27.0%) were Aboriginal or Torres Strait Islander people. During a median (inter quartile range) follow-up of 4.0 (2.1-7.6) years, 103 participants (19.3%) had major amputation, 230 (43.1%) had repeat minor amputation and 250 (46.8%) died. The risks (hazard ratio [95% CI]) of major amputation and death were not significantly higher in participants residing in rural and remote areas (0.97, 0.67-1.47; and 0.98, 0.76-1.26) or in Aboriginal or Torres Strait Islander people (HR 1.44, 95% CI 0.96, 2.16 and HR 0.89, 95% CI 0.67, 1.18). Ischemic heart disease (IHD), peripheral artery disease (PAD), osteomyelitis and foot ulceration (p<0.001 in all instances) were independent risk factors for major amputation. CONCLUSION: Major amputation and death are common following minor amputation to treat DFD and people with IHD, PAD and osteomyelitis have an increased risk of major amputation. Aboriginal and Torres Strait Islander People and residents of remote areas were not at excess risk of major amputation.


Assuntos
Amputação Cirúrgica , Pé Diabético , Havaiano Nativo ou Outro Ilhéu do Pacífico , Humanos , Amputação Cirúrgica/estatística & dados numéricos , Pé Diabético/cirurgia , Pé Diabético/etnologia , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Idoso , Fatores de Risco , Queensland/epidemiologia , Etnicidade , População Rural
2.
J Clin Med ; 13(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38893050

RESUMO

Background: This retrospective analysis of an ongoing prospective cohort study aimed to assess the outcome of revascularisation for treating lifestyle-limiting intermittent claudication caused by peripheral artery disease (PAD) in Aboriginal and Torres Strait Islander Peoples and non-Indigenous North Queenslanders. Methods: Consenting patients with PAD who underwent endovascular or open revascularisation procedures for treating lifestyle-limiting intermittent claudication were included. The primary outcome measure was major adverse limb events (MALEs), defined as major amputation or the requirement for repeat open or endovascular revascularisation. Results: Of the 378 included patients, 18 (4.8%) identified as Aboriginal and/or Torres Strait Islander Peoples. During a mean follow-up (standard deviation) of 6.0 (3.9) years, the incidence of MALE was similar in the Aboriginal and Torres Strait Islander People and non-Indigenous Australians (absolute percentage: 50.0% vs. 40.6%, log rank p = 0.59). In both unadjusted and adjusted analyses, Aboriginal and Torres Strait Islander Peoples and non-Indigenous Australians had similar risks of MALE (unadjusted hazard ratio, HR, 1.20, 95% confidence interval, CI, 0.61, 2.36; adjusted HR 1.02, 95%CI 0.50, 2.06). Conclusions: This study suggests that Aboriginal and Torres Strait Islander People are under-represented in the population of patients undergoing revascularisation to treat intermittent claudication. Due to small numbers it cannot be reliably concluded that Aboriginal and Torres Strait Islander People and non-Indigenous Australians have similar rates of MALE.

3.
Ultraschall Med ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38917825

RESUMO

PURPOSE: Post-stroke depression (PSD) is a common complication after stroke and has a substantial effect on the quality of life of patients. Nevertheless, reliable individual prediction of PSD is not possible. As depressive symptoms have been associated with brainstem raphe (BR) hypoechogenicity on transcranial sonography (TCS), we aimed to explore the association of BR hypoechogenicity and the occurrence of PSD. MATERIALS AND METHODS: The Prognostic Markers of Post-Stroke Depression (PROMoSD) study is a prospective, observational, single-center, investigator-initiated study that included patients with acute ischemic stroke (AIS) to investigate the presence of BR hypoechogenicity by TCS early after symptom onset. The primary outcome was the presence of PSD assessed at the three-month follow-up investigation by a blinded psychiatrist and defined according to the fifth version of the Diagnostic and Statistical Manual of Mental Disorders (DSM-V criteria). RESULTS: From 105 included AIS patients, 99 patients completed the study. AIS patients with a hypoechogenic BR developed a PSD at three months more frequently compared to patients with normal echogenicity (48.0% versus 4.1%, P <0.001). After adjustment for confounders (sex, mRS at follow-up, previous depressive episode), a hypoechogenic BR remained independently associated with a substantial increase in the appearance of PSD (adjusted OR: 6.371, 95%-CI: 1.181-34.362). CONCLUSION: A hypoechogenic BR is a strong and independent predictor of PSD at three months after AIS. TCS could be a routine tool to assess PSD risk in clinical practice, thereby streamlining diagnostic and therapeutic algorithms.

5.
Front Epidemiol ; 4: 1279835, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38456076

RESUMO

Introduction: Antimalarial drugs including artemisinin-based combination therapy (ACT) regimens and sulphadoxine-pyrimethamine (SP) are used in Ghana for malaria therapeutics and prophylaxis respectively. The genetic basis of Plasmodium falciparum development of drug resistance involves single nucleotide polymorphisms in genes encoding proteins for multiple cellular and metabolic processes. The prevalence of single nucleotide polymorphisms in nine P. falciparum genes linked to ACT and SP resistance in the malaria parasite population was determined. Methods: Archived filter paper blood blot samples from patients aged 9 years and below with uncomplicated malaria reporting at 10 sentinel sites located in three ecological zones for the Malaria Therapeutic Efficacy Studies were used. The samples used were collected from 2007-2018 malaria transmission seasons and mutations in the genes were detected using PCR and Sanger sequencing. Results: In all 1,142 samples were used for the study. For falcipain-2 gene (pffp2), Sanger sequencing was successful for 872 samples and were further analysed. The prevalence of the mutants was 45% (392/872) with pffp2 markers V51I and S59F occurring in 15.0% (128/872) and 3.0% (26/872) of the samples respectively. Prevalence of other P. falciparum gene mutations: coronin (pfcoronin) was 44.8% (37/90); cysteine desulfurase (pfnfs) was 73.9% (68/92); apicoplast ribosomal protein S10 (pfarps10) was 36.8% (35/95); ferredoxin (pffd) was 8.8% (8/91); multidrug resistance protein-1 (pfmrp1) was 95.2.0% (80/84); multidrug resistance protein-2 (pfmrp2) was 91.4% (32/35); dihydrofolate reductase (pfdhfr) was 99.0% (84/85); dihydropteroate synthase (pfdhps) was 72% (68/95). Discussion: The observation of numerous mutations in these genes of interest in the Ghanaian isolates, some of which have been implicated in delayed parasite clearance is of great interest. The presence of these genotypes may account for the decline in the efficacies of ACT regimens being used to treat uncomplicated malaria in the country. The need for continuous monitoring of these genetic markers to give first-hand information on parasite susceptibility to antimalarial drugs to inform policy makers and stakeholders in malaria elimination in the country is further discussed.

6.
PeerJ ; 12: e16821, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38313026

RESUMO

The force a muscle generates is dependent on muscle structure, in which fibre length, pennation angle and tendon slack length all influence force production. Muscles are not preserved in the fossil record and these parameters must be estimated when constructing a musculoskeletal model. Here, we test the capability of digitally reconstructed muscles of the Australopithecus afarensis model (specimen AL 288-1) to maintain an upright, single-support limb posture. Our aim was to ascertain the influence that different architectural estimation methods have on muscle specialisation and on the subsequent inferences that can be extrapolated about limb function. Parameters were estimated for 36 muscles in the pelvis and lower limb and seven different musculoskeletal models of AL 288-1 were produced. These parameters represented either a 'static' Hill-type muscle model (n = 4 variants) which only incorporated force, or instead a 'dynamic' Hill-type muscle model with an elastic tendon and fibres that could vary force-length-velocity properties (n = 3 variants). Each muscle's fibre length, pennation angle, tendon slack length and maximal isometric force were calculated based upon different input variables. Static (inverse) simulations were computed in which the vertical and mediolateral ground reaction forces (GRF) were incrementally increased until limb collapse (simulation failure). All AL 288-1 variants produced somewhat similar simulated muscle activation patterns, but the maximum vertical GRF that could be exerted on a single limb was not consistent between models. Three of the four static-muscle models were unable to support >1.8 times body weight and produced models that under-performed. The dynamic-muscle models were stronger. Comparative results with a human model imply that similar muscle group activations between species are needed to sustain single-limb support at maximally applied GRFs in terms of the simplified static simulations (e.g., same walking pose) used here. This approach demonstrated the range of outputs that can be generated for a model of an extinct individual. Despite mostly comparable outputs, the models diverged mostly in terms of strength.


Assuntos
Músculo Esquelético , Tendões , Humanos , Músculo Esquelético/fisiologia , Tendões/fisiologia , Extremidade Inferior , Caminhada , Pelve
7.
Nanoscale Adv ; 6(4): 1074-1083, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38356640

RESUMO

Semiconducting transition metal dichalcogenides are important optoelectronic materials thanks to their intense light-matter interaction and wide selection of fabrication techniques, with potential applications in light harvesting and sensing. Crucially, these applications depend on the lifetimes and recombination dynamics of photogenerated charge carriers, which have primarily been studied in monolayers obtained from labour-intensive mechanical exfoliation or costly chemical vapour deposition. On the other hand, liquid phase exfoliation presents a high throughput and cost-effective method to produce dispersions of mono- and few-layer nanosheets. This approach allows for easy scalability and enables the subsequent processing and formation of macroscopic films directly from the liquid phase. Here, we use transient absorption spectroscopy and spatiotemporally resolved pump-probe microscopy to study the charge carrier dynamics in tiled nanosheet films of MoS2 and WS2 deposited from the liquid phase using an adaptation of the Langmuir-Schaefer technique. We find an efficient photogeneration of charge carriers with lifetimes of several nanoseconds, which we ascribe to stabilisation at nanosheet edges. These findings provide scope for photocatalytic and photodetector applications, where long-lived charge carriers are crucial, and suggest design strategies for photovoltaic devices.

8.
Adv Mater ; 36(16): e2310499, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38100276

RESUMO

Today, ≈20% of the electric consumption is devoted to refrigeration; while, ≈50% of the final energy is dedicated to heating applications. In this scenario, many cooling devices and heat-pumps are transitioning toward the use of CO2 as an eco-friendly refrigerant, favoring carbon circular economy. Nevertheless, CO2 still has some limitations, such as large operating pressures (70-150 bar) and a critical point at 31 °C, which compromises efficiency and increases technological complexity. Very recently, an innovative breathing-caloric mechanism in the MIL-53(Al) compound is reported, which implies gas adsorption under CO2 pressurization boosted by structural transitions and which overcomes the limitations of stand-alone CO2. Here, the breathing-caloric-like effects of MOF-508b are reported, surpassing by 40% those of MIL-53(Al). Moreover, the first thermometry device operating at room temperature and under the application of only 26 bar of CO2 is presented. Under those conditions, this material presents values of ΔT ≈ 30 K, reaching heating temperatures of 56 °C and cooling temperatures of -10 °C, which are already useful for space heating, air-conditioning, food refrigeration, and freezing applications.

9.
ACS Nanosci Au ; 3(6): 462-474, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38144705

RESUMO

Surface chemistry of materials that host quantum bits such as diamond is an important avenue of exploration as quantum computation and quantum sensing platforms mature. Interfacing diamond in general and nanoscale diamond (ND) in particular with silica is a potential route to integrate room temperature quantum bits into photonic devices, fiber optics, cells, or tissues with flexible functionalization chemistry. While silica growth on ND cores has been used successfully for quantum sensing and biolabeling, the surface mechanism to initiate growth was unknown. This report describes the surface chemistry responsible for silica bond formation on diamond and uses X-ray absorption spectroscopy (XAS) to probe the diamond surface chemistry and its electronic structure with increasing silica thickness. A modified Stöber (Cigler) method was used to synthesize 2-35 nm thick shells of SiO2 onto carboxylic acid-rich ND cores. The diamond morphology, surface, and electronic structure were characterized by overlapping techniques including electron microscopy. Importantly, we discovered that SiO2 growth on carboxylated NDs eliminates the presence of carboxylic acids and that basic ethanolic solutions convert the ND surface to an alcohol-rich surface prior to silica growth. The data supports a mechanism that alcohols on the ND surface generate silyl-ether (ND-O-Si-(OH)3) bonds due to rehydroxylation by ammonium hydroxide in ethanol. The suppression of the diamond electronic structure as a function of SiO2 thickness was observed for the first time, and a maximum probing depth of ∼14 nm was calculated. XAS spectra based on the Auger electron escape depth was modeled using the NIST database for the Simulation of Electron Spectra for Surface Analysis (SESSA) to support our experimental results. Additionally, resonant inelastic X-ray scattering (RIXS) maps produced by the transition edge sensor reinforces the chemical analysis provided by XAS. Researchers using diamond or high-pressure high temperature (HPHT) NDs and other exotic materials (e.g., silicon carbide or cubic-boron nitride) for quantum sensing applications may exploit these results to design new layered or core-shell quantum sensors by forming covalent bonds via surface alcohol groups.

10.
Biology (Basel) ; 12(10)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37887067

RESUMO

Even "healthy" muscle ageing is often associated with substantial changes in muscle form and function and can lead to increased injury risks and significant negative impacts on quality of life. However, the impacts of healthy muscle ageing on the fibre architecture and microstructure of different muscles and muscle groups throughout the lower limb, and how these are related to their functional capabilities, are not fully understood. Here, a previously established framework of magnetic resonance and diffusion tensor imaging was used to measure the muscle volumes, intramuscular fat, fibre lengths and physiological cross-sectional areas of 12 lower limb muscles in a cohort of healthily aged individuals, which were compared to the same data from a young population. Maximum muscle forces were also measured from an isokinetic dynamometer. The more substantial interpopulation differences in architecture and functional performance were located within the knee extensor muscles, while the aged muscles were also more heterogeneous in muscle fibre type and atrophy. The relationships between architecture and muscle strength were also more significant in the knee extensors compared to other functional groups. These data highlight the importance of the knee extensors as a potential focus for interventions to negate the impacts of muscle ageing.

11.
Med J Aust ; 219(10): 485-495, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37872875

RESUMO

INTRODUCTION: Diabetes-related foot disease (DFD) - foot ulcers, infection, ischaemia - is a leading cause of hospitalisation, disability, and health care costs in Australia. The previous 2011 Australian guideline for DFD was outdated. We developed new Australian evidence-based guidelines for DFD by systematically adapting suitable international guidelines to the Australian context using the ADAPTE and GRADE approaches recommended by the NHMRC. MAIN RECOMMENDATIONS: This article summarises the most relevant of the 98 recommendations made across six new guidelines for the general medical audience, including: prevention - screening, education, self-care, footwear, and treatments to prevent DFD; classification - classifications systems for ulcers, infection, ischaemia and auditing; peripheral artery disease (PAD) - examinations and imaging for diagnosis, severity classification, and treatments; infection - examinations, cultures, imaging and inflammatory markers for diagnosis, severity classification, and treatments; offloading - pressure offloading treatments for different ulcer types and locations; and wound healing - debridement, wound dressing selection principles and wound treatments for non-healing ulcers. CHANGES IN MANAGEMENT AS A RESULT OF THE GUIDELINE: For people without DFD, key changes include using a new risk stratification system for screening, categorising risk and managing people at increased risk of DFD. For those categorised at increased risk of DFD, more specific self-monitoring, footwear prescription, surgical treatments, and activity management practices to prevent DFD have been recommended. For people with DFD, key changes include using new ulcer, infection and PAD classification systems for assessing, documenting and communicating DFD severity. These systems also inform more specific PAD, infection, pressure offloading, and wound healing management recommendations to resolve DFD.


Assuntos
Diabetes Mellitus , Pé Diabético , Doenças do Pé , Humanos , Pé Diabético/diagnóstico , Pé Diabético/prevenção & controle , Úlcera , Austrália , Isquemia
12.
Musculoskeletal Care ; 21(4): 1482-1496, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37807828

RESUMO

BACKGROUND: Low back pain (LBP) is a common complex condition, where specific diagnoses are hard to identify. Diagnostic clinical prediction rules (CPRs) are known to improve clinical decision-making. A review of LBP diagnostic-CPRs by Haskins et al. (2015) identified six diagnostic-CPRs in derivation phases of development, with one tool ready for implementation. Recent progress on these tools is unknown. Therefore, this review aimed to investigate developments in LBP diagnostic-CPRs and evaluate their readiness for implementation. METHODS: A systematic review was performed on five databases (Medline, Amed, Cochrane Library, PsycInfo, and CINAHL) combined with hand-searching and citation-tracking to identify eligible studies. Study and tool quality were appraised for risk of bias (Quality Assessment of Diagnostic Accuracy Studies-2), methodological quality (checklist using accepted CPR methodological standards), and CPR tool appraisal (GRade and ASsess Predictive). RESULTS: Of 5021 studies screened, 11 diagnostic-CPRs were identified. Of the six previously known, three have been externally validated but not yet undergone impact analysis. Five new tools have been identified since Haskin et al. (2015); all are still in derivation stages. The most validated diagnostic-CPRs include the Lumbar-Spinal-Stenosis-Self-Administered-Self-Reported-History-Questionnaire and Diagnosis-Support-Tool-to-Identify-Lumbar-Spinal-Stenosis, and the StEP-tool which differentiates radicular from axial-LBP. CONCLUSIONS: This updated review of LBP diagnostic CPRs found five new tools, all in the early stages of development. Three previously known tools have now been externally validated but should be used with caution until impact evaluation studies are undertaken. Future funding should focus on externally validating and assessing the impact of existing CPRs on clinical decision-making.


Assuntos
Regras de Decisão Clínica , Dor Lombar , Humanos , Dor Lombar/diagnóstico , Técnicas de Apoio para a Decisão , Constrição Patológica , Tomada de Decisão Clínica
13.
J Int Med Res ; 51(9): 3000605231197461, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37776529

RESUMO

OBJECTIVES: Acute pancreatitis (AP) is a severe complication of leptospirosis. This review focuses on the current evidence of AP in patients with leptospirosis. METHODS: Data on clinical characteristics, biochemical parameters, diagnosis, complications, critical care, fluid management, operative management, and outcomes were analyzed. This study was registered in PROSPERO (CRD42022360802). RESULTS: We included 35 individual case reports and 4 case series involving 79 patients. Sex was reported for 48 (60.7%) patients; 38 (48.1%) were male and 10 (12.6%) were female. The patients' mean age was 45.13 (15-83 years). Acute kidney injury, thrombocytopenia, hypotension, and liver injury were the most common complications reported. Complete recovery was reported for 36 (45.5%) patients. Biochemical and radiological recovery was reported for 10 (12.6%) and 9 (11.3%) patients, respectively. Death was reported in 18 (22.7%) patients. CONCLUSION: A high degree of clinical suspicion and different modalities of investigations are essential in the diagnosis of AP in leptospirosis. AP can be easily missed in leptospirosis because both conditions share similar clinical presentations and complications. Because of the high prevalence of acute kidney injury, judicious fluid management and close monitoring are mandatory.


Assuntos
Injúria Renal Aguda , Leptospirose , Pancreatite , Trombocitopenia , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Pancreatite/complicações , Pancreatite/terapia , Pancreatite/diagnóstico , Doença Aguda , Leptospirose/complicações , Leptospirose/epidemiologia , Injúria Renal Aguda/terapia , Injúria Renal Aguda/complicações
15.
Rural Remote Health ; 23(3): 7521, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37545165

RESUMO

INTRODUCTION: Globally, primary care organisations responded rapidly to COVID-19 physical distancing requirements through the adoption of telehealth to maintain the delivery of health care to communities. In Australia, temporary Medicare Benefits Schedule (MBS) telehealth items were introduced in March 2020 to enable the provision of telehealth services in the primary care setting. These changes included funding for two modes of telehealth delivery: videoconferencing and telephone consultations. As primary care organisations, Aboriginal Community Controlled Health Organisations (ACCHOs) rapidly adopted telehealth consultations to maintain the delivery of primary care services to Aboriginal and Torres Strait Islander clients. The aim of the present study was to evaluate the implementation (specifically the uptake, acceptability and requirements for delivery) of telehealth primary healthcare services for Aboriginal and/or Torres Strait Islander peoples by a rural ACCHO during COVID-19. METHODS: A single-site convergent-parallel mixed-methods study was undertaken in the context of an ongoing research partnership established between a rural ACCHO and a university department of rural health. De-identified health service data from March 2020 to March 2021 was extracted, including MBS telehealth consultations and client demographics (eg age, gender and postcode). Variables were analysed using descriptive statistics to examine the uptake of telehealth by Aboriginal and Torres Strait Islander clients. A geographical analysis of postcode data was also undertaken. Semi-structured interviews were undertaken concurrently with a purposive sample of health service personnel (including health professionals) involved in the implementation or delivery of telehealth, and Aboriginal and/or Torres Strait Islander clients who had accessed telehealth, to explore the acceptability of telehealth and requirements for delivery. Thematic analysis using an inductive approach was undertaken. The analyses of quantitative and qualitative findings were merged to identify key concepts pertaining to the uptake, acceptability and requirements for telehealth delivery. RESULTS: During the first year of implementation, 435 telehealth primary healthcare consultations were delivered to Aboriginal and/or Torres Strait Islander clients. Seven health personnel and six Aboriginal and/or Torres Strait Islander clients participated in interviews. Merged findings from an analysis of quantitative and qualitative data were grouped under three concepts: uptake of telehealth consultations by Aboriginal and Torres Strait Islander clients, maintaining the delivery of ACCHO services during COVID-19, and implications for sustaining telehealth in an ACCHO. Findings identified that telehealth maintained the delivery of ACCHO services to Aboriginal and/or Torres Strait Islander clients across the lifespan during COVID-19, despite a preference for face-to-face consultations. A greater uptake of telephone consultations compared to videoconferencing was identified. Barriers to the utilisation of videoconferencing were largely technology related, highlighting the need for additional support for clients. CONCLUSION: Telehealth was a useful addition to face-to-face consultations when used in the appropriate context such as the administration of long-term medication prescriptions by a GP. Engaging the ACCHO sector in the policy discourse around telehealth is imperative for identifying requirements for ongoing implementation.


Assuntos
Povos Aborígenes Australianos e Ilhéus do Estreito de Torres , COVID-19 , Serviços de Saúde do Indígena , Programas Nacionais de Saúde , Atenção Primária à Saúde , Telemedicina , Idoso , Humanos , Pandemias , Austrália , População Rural
16.
Inorg Chem ; 62(27): 10613-10625, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37369076

RESUMO

High-valent iron species have been implicated as key intermediates in catalytic oxidation reactions, both in biological and synthetic systems. Many heteroleptic Fe(IV) complexes have now been prepared and characterized, especially using strongly π-donating oxo, imido, or nitrido ligands. On the other hand, homoleptic examples are scarce. Herein, we investigate the redox chemistry of iron complexes of the dianonic tris-skatylmethylphosphonium (TSMP2-) scorpionate ligand. One-electron oxidation of the tetrahedral, bis-ligated [(TSMP)2FeII]2- leads to the octahedral [(TSMP)2FeIII]-. The latter undergoes thermal spin-cross-over both in the solid state and solution, which we characterize using superconducting quantum inference device (SQUID), Evans method, and paramagnetic nuclear magnetic resonance spectroscopy. Furthermore, [(TSMP)2FeIII]- can be reversibly oxidized to the stable high-valent [(TSMP)2FeIV]0 complex. We use a variety of electrochemical, spectroscopic, and computational techniques as well as SQUID magnetometry to establish a triplet (S = 1) ground state with a metal-centered oxidation and little spin delocalization on the ligand. The complex also has a fairly isotropic g-tensor (giso = 1.97) combined with a positive zero-field splitting (ZFS) parameter D (+19.1 cm-1) and very low rhombicity, in agreement with quantum chemical calculations. This thorough spectroscopic characterization contributes to a general understanding of octahedral Fe(IV) complexes.

17.
Eur J Vasc Endovasc Surg ; 66(2): 221-228, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37196911

RESUMO

OBJECTIVE: Diabetes related foot disease (DFD) is a common reason for admission to hospital, but the predictive factors for repeat admission are poorly defined. The primary aim of this study was to identify rates and predictive factors for DFD related hospital re-admission. METHODS: Patients admitted to hospital for treatment of DFD at a single regional centre were recruited prospectively between January 2020 and December 2020. Participants were followed for 12 months to evaluate the primary outcome of hospital re-admission. The relationship between predictive factors and re-admission were examined using non-parametric statistical tests and Cox proportional hazard analyses. RESULTS: The median age of the 190 participants was 64.9 (standard deviation 13.3) years and 68.4% were male. Forty-one participants (21.6%) identified themselves as Aboriginal or Torres Strait Islander people. One hundred participants (52.6%) were re-admitted to hospital at least once over 12 months. The commonest reason for re-admission was for treatment of foot infection (84.0% of first re-admission). Absent pedal pulses (unadjusted hazard ratio [HR] 1.90; 95% confidence interval [CI] 1.26 - 2.85), loss of protective sensation (LOPS) (unadjusted HR 1.98; 95% CI 1.08 - 3.62), and male sex (unadjusted HR 1.62; 95% CI 1.03 - 2.54) increased the risk of re-admission. After risk adjustment, only absence of pedal pulses (HR 1.92, 95% CI 1.27 - 2.91) and LOPS (HR 2.02, 95% CI 1.09 - 3.74) significantly increased the risk of re-admission. CONCLUSION: Over 50% of patients admitted to hospital for treatment of DFD are re-admitted within one year. Patients with absent pedal pulses and those with LOPS are twice as likely to be re-admitted.


Assuntos
Diabetes Mellitus , Doenças do Pé , Humanos , Masculino , Adolescente , Feminino , Estudos Prospectivos , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Fatores de Risco , Hospitais
18.
Eur J Vasc Endovasc Surg ; 66(2): 237-244, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37209994

RESUMO

OBJECTIVE: This retrospective cohort study investigated the anatomical distribution, severity, and outcome of peripheral artery disease (PAD) in Aboriginal and Torres Strait Islanders compared with non-indigenous Australians. METHODS: The distribution, severity, and outcome of PAD were assessed using a validated angiographic scoring system and review of medical records in a cohort of Aboriginal and Torres Strait Islander and non-indigenous Australians. The relationship between ethnicity and PAD severity, distribution, and outcome were examined using non-parametric statistical tests, Kaplan-Meier and Cox proportional hazard analyses. RESULTS: Seventy-three Aboriginal and Torres Strait Islanders and 242 non-indigenous Australians were included and followed for a median of 6.7 [IQR 2.7, 9.3] years. Aboriginal and Torres Strait Islander patients were more likely to present with symptoms of chronic limb threatening ischaemia (81% vs. 25%; p < .001), had greater median [IQR] angiographic scores for the symptomatic limb (7 [5, 10] vs. 4 [2, 7]) and tibial arteries (5 [2, 6] vs. 2 [0, 4]) and had higher risk of major amputation (HR 6.1, 95% CI 3.6 - 10.5; p < .001) and major adverse cardiovascular events (HR 1.5, 95% CI 1.0 - 2.3; p = .036) but not for revascularisation (HR 0.8, 95% CI 0.5 - 1.3; p = .37) compared with non-indigenous Australians. The associations with major amputation and major adverse cardiovascular events were no longer statistically significant when adjusted for limb angiographic score. CONCLUSION: Compared with non-indigenous patients, Aboriginal and Torres Strait Islander Australians had more severe tibial artery disease and a higher risk of major amputation and major adverse cardiovascular events.


Assuntos
Povos Aborígenes Australianos e Ilhéus do Estreito de Torres , Isquemia Crônica Crítica de Membro , Humanos , Estudos de Coortes , Estudos Retrospectivos , Austrália/epidemiologia
19.
Ecol Evol ; 13(3): e9855, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36960236

RESUMO

Abiotic factors are usually considered key drivers of species distribution at macro scales, while biotic interactions are mostly used at local scales. A few studies have explored the role of biotic interactions at macro scales, but all considered a limited number of species and obligate interactions. We examine the role of biotic interactions in large-scale SDMs by testing two main hypotheses: (1) biotic factors in SDMs can have an important role at continental scale; (2) the inclusion of biotic factors in large-scale SDMs is important also for generalist species. We used a maximum entropy algorithm to model the distribution of 177 bat species in Africa calibrating two SDMs for each species: one considering only abiotic variables (noBIO-SDMs) and the other (BIO-SDMs) including also biotic variables (trophic resource richness). We focused the interpretation of our results on variable importance and response curves. For each species, we also compared the potential distribution measuring the percentage of change between the two models in each pixel of the study area. All models gave AUC >0.7, with values on average higher in BIO-SDMs compared to noBIO-SDMs. Trophic resources showed an importance overall higher level than all abiotic predictors in most of the species (~68%), including generalist species. Response curves were highly interpretable in all models, confirming the ecological reliability of our models. Model comparison between the two models showed a change in potential distribution for more than 80% of the species, particularly in tropical forests and shrublands. Our results highlight the importance of considering biotic interactions in SDMs at macro scales. We demonstrated that a generic biotic proxy can be important for modeling species distribution when species-specific data are not available, but we envision that a multi-scale analysis combined with a better knowledge of the species might provide a better understanding of the role of biotic interactions.

20.
Artigo em Inglês | MEDLINE | ID: mdl-36897774

RESUMO

BACKGROUND: Ankle joint dorsiflexion range of motion is essential to normal gait. Ankle equinus has been implicated in a number of foot and ankle pathologies included Achilles tendonitis, plantar fasciitis, ankle injury, forefoot pain, and foot ulceration. Reliable measurement of ankle joint dorsiflexion range of motion, both clinically and in a research setting, is important. METHODS: The primary aim of this study was to investigate the intertester reliability of an innovative device for measuring ankle joint dorsiflexion range of motion. A total of 31 (n = 31) participants volunteered to take part in this study. A paired t-test was performed to assess for systematic differences between the mean measures of each rater. Intertester reliability was evaluated using the intraclass correlation coefficient (ICC) and their 95% confidence intervals. RESULTS: A paired t-test demonstrated that the mean ankle joint dorsiflexion range of motion did not significantly differ between raters. The ankle joint ROM mean for rater 1 was 4.65 SD (3.71) and rater 2 was 4.67 SD (3.91). Intertester reliability for the use of the Dorsi-Meter was excellent and demonstrated a very narrow range of error. The ICC (95%CI) was 0.991 (0.980 to 0.995) the SEM (in degrees) was 0.07, the MDC95, in degrees was 0.19 and 95% LOA, degrees was -1.49 to 1.46. CONCLUSIONS: We found the intertester reliability of the Dorsi-Meter to demonstrate higher levels of intertester reliability compared to previous studies investigating other devices. We reported the MDC values to provide an estimate of the smallest amount of change in the ankle joint dorsiflexion range of motion that must be achieved to reflect a true change, outside the error of the test. The Dorsi-Meter has been established as an appropriate reliable device to measure ankle joint dorsiflexion for clinicians and researchers with very small minimal detectable change and limits of agreement.


Assuntos
Traumatismos do Tornozelo , Articulação do Tornozelo , Humanos , Reprodutibilidade dos Testes , Amplitude de Movimento Articular , Extremidade Inferior
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