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1.
Physiology (Bethesda) ; 38(2): 0, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36317939

RESUMEN

Developmental hypoxia has profound and persistent effects on the vertebrate cardiovascular system, but the nature, magnitude, and long-term outcome of the hypoxic consequences are species specific. Here we aim to identify common and novel cardiovascular responses among vertebrates that encounter developmental hypoxia, and we discuss the possible medical and ecological implications.


Asunto(s)
Sistema Cardiovascular , Humanos , Animales , Vertebrados , Hipoxia , Corazón/fisiología
5.
Artículo en Inglés | MEDLINE | ID: mdl-38884530

RESUMEN

PURPOSE: Mohs micrographic surgery with immunohistochemistry allows for same-day comprehensive margin assessment of melanoma in situ prior to subspecialty reconstruction. This study describes the oncologic and reconstructive outcomes of eyelid and periorbital melanoma in situ and identifies risk factors for complex reconstructive demands. METHODS: Retrospective case series of all patients treated with Mohs micrographic surgery with immunohistochemistry for melanoma in situ affecting the eyelids or periorbital region from 2008 to 2018 at a single institution. Tumors were assigned to the eyelid group if the clinically visible tumor involved the skin inside the orbital rim. Reconstructive variables were compared between the eyelid and periorbital cohorts. RESULTS: There were 24 eyelid and 141 periorbital tumors included. The initial surgical margin for all tumors was 5.34 ± 1.54 mm and multiple Mohs stages were required in 24.2% of cases. Eyelid tumors included more recurrences (p = 0.003), and the average defect size was larger (14.0 ± 13.3 cm2 vs. 7.7 ± 5.4 cm2, p = 0.03). Risk factors for complex reconstruction included: initial tumor diameter >2 cm (odds ratio [OR]: 3.84, 95% confidence interval [CI]: 1.95-7.57) and eyelid involved by initial tumor (OR: 4.88, 95% CI: 1.94-12.28). At an average follow-up of 4.8 years, there were no melanoma-related deaths and 1 local recurrence (0.6% recurrence rate). CONCLUSIONS: Mohs micrographic surgery with immunohistochemistry achieves excellent local control rates for periocular melanoma in situ. An initial surgical margin of 5 mm is frequently insufficient to achieve clear margins. The resulting defects are large, and the complexity of reconstruction can be predicted by tumor size and clinical involvement of eyelid skin.

6.
Nature ; 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35732723
7.
Harm Reduct J ; 20(1): 125, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37670361

RESUMEN

BACKGROUND: Aboriginal and Torres Strait Islander Australians are disproportionately impacted by blood-borne viruses (BBVs) and sexually transmissible infections (STIs). Stigma remains one of the key barriers to testing and treatment for BBVs and STIs, particularly among Aboriginal and Torres Strait Islander people. The Deadly Liver Mob (DLM) is a peer-delivered incentivised health promotion program by and for Aboriginal and Torres Strait Islander Australians. The program aims to increase access to BBV and STI education, screening, treatment, and vaccination for Aboriginal and Torres Strait Islander Australians in recognition of the systemic barriers for First Nations people to primary care, including BBV- and STI-related stigma, and institutional racism. This paper presents routinely collected data across nine sites on the 'cascade of care' progression of Aboriginal and Torres Strait Islander clients through the DLM program: hepatitis C education, screening, returning for results, and recruitment of peers. METHODS: Routinely collected data were collated from each of the DLM sites, including date of attendance, basic demographic characteristics, eligibility for the program, recruitment of others, and engagement in the cascade of care. RESULTS: Between 2013 and 2020, a total of 1787 Aboriginal and Torres Strait Islander clients were educated as part of DLM, of which 74% went on to be screened and 42% (or 57% of those screened) returned to receive their results. The total monetary investment of the cascade of care progression was approximately $56,220. Data highlight the positive impacts of the DLM program for engagement in screening, highlighting the need for culturally sensitive, and safe programs led by and for Aboriginal and Torres Strait Islander people. However, the data also indicate the points at which clients 'fall off' the cascade, underscoring the need to address any remaining barriers to care. CONCLUSIONS: The DLM program shows promise in acting as a 'one stop shop' in addressing the needs of Aboriginal and Torres Strait Islander people in relation to BBVs and STIs. Future implementation could focus on addressing any potential barriers to participation in the program, such as co-location of services and transportation.


Asunto(s)
Aborigenas Australianos e Isleños del Estrecho de Torres , Infecciones de Transmisión Sanguínea , Accesibilidad a los Servicios de Salud , Enfermedades de Transmisión Sexual , Humanos , Australia , Hepacivirus , Hígado , Nueva Gales del Sur , Enfermedades de Transmisión Sexual/diagnóstico , Infecciones de Transmisión Sanguínea/diagnóstico
8.
Harm Reduct J ; 20(1): 153, 2023 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-37864234

RESUMEN

The Deadly Liver Mob (DLM) is a peer-delivered incentivised health promotion program by and for Aboriginal and Torres Strait Islander Australians, and was introduced in response to the disproportionate number of Aboriginal and Torres Strait Islander Australians who are impacted by blood borne viruses (BBVs) and sexually transmitted infections (STIs). The goal of the program is to increase access to BBV and STI education, screening, treatment, and vaccination in recognition and response to the systemic barriers that Aboriginal and Torres Strait Islander peoples face in accessing health care. This commentary introduces a series of papers that report on various aspects of the evaluation of the Deadly Liver Mob (DLM) program. In this paper, we explain what DLM is and how we constructed an evaluation framework for this complex health promotion intervention.


Asunto(s)
Aborigenas Australianos e Isleños del Estrecho de Torres , Enfermedades Transmisibles , Promoción de la Salud , Hepatitis C , Humanos , Australia , Servicios de Salud del Indígena , Hepacivirus , Hepatitis C/etnología , Hepatitis C/prevención & control , Nueva Gales del Sur , Enfermedades de Transmisión Sexual/diagnóstico , Enfermedades de Transmisión Sexual/terapia , Grupo Paritario , Enfermedades Transmisibles/diagnóstico , Enfermedades Transmisibles/terapia , Infecciones de Transmisión Sanguínea/diagnóstico , Infecciones de Transmisión Sanguínea/terapia
9.
J Pineal Res ; 73(3): e12821, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35941749

RESUMEN

Insufficient oxygen supply (hypoxia) during fetal development leads to cardiac remodeling and a predisposition to cardiovascular disease in later life. Previous work has shown hypoxia causes oxidative stress in the fetal heart and alters the activity and expression of mitochondrial proteins in a sex-dependent manner. However, the functional effects of these modifications on mitochondrial respiration remain unknown. Furthermore, while maternal antioxidant treatments are emerging as a promising new strategy to protect the hypoxic fetus, whether these treatments convey similar protection to cardiac mitochondria in the male or female fetus has not been investigated. Therefore, using an established rat model, we measured the sex-dependent effects of gestational hypoxia and maternal melatonin treatment on fetal cardiac mitochondrial respiration, reactive oxygen species (ROS) production, and lipid peroxidation. Pregnant Wistar rats were subjected to normoxia or hypoxia (13% oxygen) during gestational days (GDs) 6-20 (term ~22 days) with or without melatonin treatment (5 µg/ml in maternal drinking water). On GD 20, mitochondrial aerobic respiration and H2 O2 production were measured in fetal heart tissue, together with lipid peroxidation and citrate synthase (CS) activity. Gestational hypoxia reduced maternal body weight gain (p < .01) and increased placental weight (p < .05) but had no effect on fetal weight or litter size. Cardiac mitochondria from male but not female fetuses of hypoxic pregnancy had reduced respiratory capacity at Complex II (CII) (p < .05), and an increase in H2 O2 production/O2 consumption (p < .05) without any changes in lipid peroxidation. CS activity was also unchanged in both sexes. Despite maternal melatonin treatment increasing maternal and fetal plasma melatonin concentration (p < .001), melatonin treatment had no effect on any of the mitochondrial parameters investigated. To conclude, we show that gestational hypoxia leads to ROS generation from the mitochondrial electron transport chain and affects fetal cardiac mitochondrial respiration in a sex-dependent manner. We also show that maternal melatonin treatment had no effect on these relationships, which has implications for the development of future therapies for hypoxic pregnancies.


Asunto(s)
Melatonina , Animales , Femenino , Corazón Fetal/metabolismo , Hipoxia/metabolismo , Masculino , Melatonina/metabolismo , Melatonina/farmacología , Mitocondrias Cardíacas/metabolismo , Estrés Oxidativo , Oxígeno/metabolismo , Oxígeno/farmacología , Placenta , Embarazo , Ratas , Ratas Wistar , Especies Reactivas de Oxígeno/metabolismo
10.
Nature ; 2021 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-34172961
11.
Nature ; 2021 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-34588652
12.
Anal Chem ; 93(2): 1009-1015, 2021 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-33290053

RESUMEN

We describe a method for the analysis of organic acids, including those of the tricarboxylic acid cycle (TCA cycle), by mixed-mode reversed-phase chromatography, on a CSH Phenyl-Hexyl column, to accomplish mixed-mode anion-exchange separations, which results in increased retention for acids without the need for ion-pairing reagents or other mobile phase additives. The developed method exhibited good retention time reproducibility for over 650 injections or more than 5 days of continuous operation. Additionally, it showed excellent resolution of the critical pairs, isocitric acid and citric acid as well as malic acid and fumaric acid, among others. The use of hybrid organic-inorganic surface technology incorporated into the hardware of the column not only improved the mass spectral quality and subsequent database match scoring but also increased the recovery of the analytes, showing particular benefit for low concentrations of phosphorylated species. The method was applied to the comparative metabolomic analysis of urine samples from healthy controls and breast cancer positive subjects. Unsupervised PCA analysis showed distinct grouping of samples from healthy and diseased subjects, with excellent reproducibility of respective injection clusters. Finally, abundance plots of selected analytes from the tricarboxylic acid cycle revealed differences between healthy control and disease groups.


Asunto(s)
Líquidos Corporales/metabolismo , Ciclo del Ácido Cítrico , Ácido Cítrico/metabolismo , Fumaratos/metabolismo , Isocitratos/metabolismo , Malatos/metabolismo , Líquidos Corporales/química , Cromatografía Líquida de Alta Presión , Ácido Cítrico/química , Ácido Cítrico/orina , Fumaratos/química , Fumaratos/orina , Humanos , Isocitratos/química , Isocitratos/orina , Malatos/química , Malatos/orina , Espectrometría de Masas , Estructura Molecular
13.
Rapid Commun Mass Spectrom ; 34(18): e8851, 2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-32492222

RESUMEN

RATIONALE: The presence of lipids in animal tissues can influence the interpretation of stable isotope data, particularly in lipid-rich tissues such as the skin and muscle of marine mammals. The traditionally employed chloroform-methanol delipidation protocol has the potential to alter δ15 N values in proteinaceous tissues. Our objective was to determine whether the use of cyclohexane could be an alternative extraction method, effectively removing lipids without altering δ15 N values. METHODS: Kidney, liver, muscle, and skin samples were collected from beach-cast Sowerby's beaked whales (Mesoplodon bidens). Control subsamples were processed without delipidation extraction, and duplicate subsamples were extracted with either chloroform-methanol or cyclohexane. δ13 C, δ15 N, and C:N values were determined by continuous-flow elemental analysis isotope ratio mass spectrometry. Paired Wilcoxon tests were used to evaluate the change in isotope ratios after extraction, and unpaired Wilcoxon tests were used to evaluate differences in isotope ratios between extractions. RESULTS: Use of cyclohexane is an effective delipidation technique for tissues with low and moderate lipid content. Chemical delipidation influenced δ15 N values; extracted samples generally showed an increase in δ15 N values which varied from 0.0‰ to 1.7‰. Chloroform-methanol extraction resulted in alterations to δ15 N values greater than the analytical precision for all analyzed tissues. Changes to δ15 N values after cyclohexane extraction were at or near the analytical precision for liver and muscle but greater than the analytical precision for kidney and skin. CONCLUSIONS: We recommend processing duplicate subsamples for stable isotope analysis, one with and one without extraction, in order to obtain accurate values for each isotope ratio. Prolonged chemical extractions are not necessary to effectively remove lipids. When samples are limited, we suggest using cyclohexane for tissues with low or moderate lipid content, and chloroform-methanol for lipid-rich tissues.


Asunto(s)
Isótopos de Carbono/análisis , Fraccionamiento Químico/métodos , Lípidos/aislamiento & purificación , Isótopos de Nitrógeno/análisis , Ballenas/fisiología , Animales , Cloroformo/química , Ciclohexanos/química , Riñón/química , Hígado/química , Espectrometría de Masas , Metanol/química , Escocia
14.
Biomed Chromatogr ; 34(9): e4840, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32251526

RESUMEN

Vangueria agrestis is a shrub indigenous to tropical Africa, belonging to family Rubiaceae and is traditionally used as a decoction for treatment of fever, pain, and malaria. This study was undertaken to investigate the chemical constituents based on precursor exact mass and fragment ion information. The chemical profiling and structural characteristics of chemical constituents from methanolic extracts of dried aerial parts and roots of V. agrestis and dietary supplements were analyzed using ultra-high-performance liquid chromatography/ion mobility quadrupole time-of-flight mass spectrometry coupled with UNIFI platform and multivariate analysis in both negative and positive ion modes. A non-targeted ultra-high-performance liquid chromatography-mass spectrometry analysis was carried out to profile the chemical constituents of crude extracts of V. agrestis, and 73 compounds, including reference compounds, were identified. The fragments of flavonoids, monoterpene, and triterpene glycosides revealed the characteristic cleavage of glycosidic linkages, and the fragmentation pattern provided the identity of the sugars. This analytical method provides a quick method for quality assessment of dietary supplements. Finally, a chemometrics approach with multivariate statistical tools was used to visualize the differences between root and aerial parts of plant samples and to find the potential chemical markers that differentiate among these parts of V. agrestis samples and dietary supplements.


Asunto(s)
Flavonoides/análisis , Glicósidos/análisis , Extractos Vegetales/química , Rubiaceae/química , Terpenos/análisis , Cromatografía Líquida de Alta Presión/métodos , Suplementos Dietéticos/análisis , Flavonoides/química , Glicósidos/química , Espectrometría de Masas , Fenoles/análisis , Fenoles/química , Componentes Aéreos de las Plantas/química , Raíces de Plantas/química , Terpenos/química
15.
Nature ; 554(7693): 426-428, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32094962
18.
Int J Mol Sci ; 20(3)2019 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-30678313

RESUMEN

Eleutherococcus senticosus Maxim. belongs to the Araliaceae family. Phytochemical studies reveal that E. senticosus leaves contain triterpene glycosides along with organic acid derivatives and flavonoid compounds. It is believed that E. senticosus is similar to ginseng because they come from same family and both contain triterpene saponins. E. senticosus leaves have been developed as a functional beverage called ci-wu-jia tea in recent years. Triterpene glycosides are difficult to identify by ultraviolet (UV) detection and contents of these compounds are low in E. senticosus leaves. In this study, a sensitive ultra-high performance liquid chromatographic (UHPLC) method combining UV and tandem mass spectrometry (MS/MS) was developed to characterize the triterpene glycosides from E. senticosus leaves and related commercial products. Fragmentation patterns of three sub-groups of triterpene glycosides in E. senticosus leaves were investigated. Additionally, fragmentation pathways and UV characteristics of organic acid derivatives and flavonoids were also characterized. A compound screening library, including 241 compounds reported in the literature, was created and used to confirm the compounds in the samples. In this study, a total of 24 samples, including 13 plant samples of E. senticosus and 11 ci-wu-jia tea products, were analyzed. Out of the 11 commercial products, three products were discovered to contain green tea (Camellia sinensis) that was considered to be an adulterant since it was not an ingredient on the labels. The developed UHPLC-UV-MS/MS analytical method combined with the UNIFI processing method can simultaneously characterize organic acid derivatives, flavonoids, and triterpene saponins from E. senticosus. It provides a simple and sensitive way to perform quality control of E. senticosus and related ci-wu-jia tea products.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Eleutherococcus/química , Extractos Vegetales/química , Espectrometría de Masas en Tándem/métodos , Flavonoides/química , Glicósidos/química , Ácido Quínico/química , Triterpenos/química
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