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1.
ACS Omega ; 9(12): 14580-14591, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38560003

ABSTRACT

With the global escalation of concerns surrounding prostate cancer (PCa) diagnosis, reliance on the serologic prostate-specific antigen (PSA) test remains the primary approach. However, the imperative for early PCa diagnosis necessitates more effective, accurate, and rapid diagnostic point-of-care (POC) devices to enhance the result reliability and minimize disease-related complications. Among POC approaches, electrochemical biosensors, known for their amenability and miniaturization capabilities, have emerged as promising candidates. In this study, we developed an impedimetric sensing platform to detect urinary zinc (UZn) in both artificial and clinical urine samples. Our approach lies in integrating label-free impedimetric sensing and the introduction of porosity through surface modification techniques. Leveraging a cellulose acetate/reduced graphene oxide composite, our sensor's recognition layer is engineered to exhibit enhanced porosity, critical for improving the sensitivity, capture, and interaction with UZn. The sensitivity is further amplified by incorporating zincon as an external dopant, establishing highly effective recognition sites. Our sensor demonstrates a limit of detection of 7.33 ng/mL in the 0.1-1000 ng/mL dynamic range, which aligns with the reference benchmark samples from clinical biochemistry. Our sensor results are comparable with the results of inductively coupled plasma mass spectrometry (ICP-MS) where a notable correlation of 0.991 is achieved. To validate our sensor in a real-life scenario, tests were performed on human urine samples from patients being investigated for prostate cancer. Testing clinical urine samples using our sensing platform and ICP-MS produced highly comparable results. A linear correlation with R2 = 0.964 with no significant difference between two groups (p-value = 0.936) was found, thus confirming the reliability of our sensing platform.

2.
J Transl Med ; 21(1): 284, 2023 04 28.
Article in English | MEDLINE | ID: mdl-37118813

ABSTRACT

BACKGROUND: Micronutrients have been associated with disease severity and poorer clinical outcomes in patients with COVID-19. However, there is a paucity of studies examining if the relationship with micronutrient status and clinical outcomes is independent of recognised prognostic factors, specifically frailty and the systemic inflammatory response (SIR). The aim of the present study was to examine the relationship between micronutrient status, frailty, systemic inflammation, and clinical outcomes in patients admitted with COVID-19. METHODS: Retrospective analysis of prospectively collected data was performed on patients with confirmed COVID-19, admitted to hospital between the 1st April 2020-6th July 2020. Clinicopathological characteristics, frailty assessment, biochemical and micronutrient laboratory results were recorded. Frailty status was determined using the Clinical Frailty scale. SIR was determined using serum CRP. Clinical outcomes of interest were oxygen requirement, ITU admission and 30-day mortality. Categorical variables were analysed using chi-square test and binary logistics regression analysis. Continuous variables were analysed using the Mann-Whitney U or Kruskal Wallis tests. RESULTS: 281 patients were included. 55% (n = 155) were aged ≥ 70 years and 39% (n = 109) were male. 49% (n = 138) of patients were frail (CFS > 3). 86% (n = 242) of patients had a serum CRP > 10 mg/L. On univariate analysis, frailty was significantly associated with thirty-day mortality (p < 0.001). On univariate analysis, serum CRP was found to be significantly associated with an oxygen requirement on admission in non-frail patients (p = 0.004). Over a third (36%) of non-frail patients had a low vitamin B1, despite having normal reference range values of red cell B2, B6 and selenium. Furthermore, serum CRP was found to be significantly associated with a lower median red cell vitamin B1 (p = 0.029). CONCLUSION: Vitamin B1 stores may be depleted in COVID-19 patients experiencing a significant SIR and providing rationale for thiamine supplementation. Further longitudinal studies are warranted to delineate the trend in thiamine status following COVID-19.


Subject(s)
COVID-19 , Frailty , Humans , Male , Female , Frailty/complications , COVID-19/complications , Retrospective Studies , Micronutrients , Inflammation , Hospitals , Thiamine
3.
PLoS One ; 16(5): e0251924, 2021.
Article in English | MEDLINE | ID: mdl-34043668

ABSTRACT

BACKGROUND: In order to manage the COVID-19 systemic inflammatory response, it is important to identify clinicopathological characteristics across multiple cohorts. METHODS: The aim of the present study was to compare the 4C mortality score, other measures of the systemic inflammatory response and clinicopathological characteristics in two consecutive cohorts of patients on admission with COVID-19. Electronic patient records for 2 consecutive cohorts of patients admitted to two urban teaching hospitals with COVID-19 during two 7-week periods of the COVID-19 pandemic in Glasgow, U.K. (cohort 1: 17/3/2020-1/5/2020) and (cohort 2: 18/5/2020-6/7/2020) were examined for routine clinical, laboratory and clinical outcome data. RESULTS: Compared with cohort 1, cohort 2 were older (p<0.001), more likely to be female (p<0.05) and have less independent living circumstances (p<0.001). More patients in cohort 2 were PCR positive, CXR negative (both p<0.001) and had low serum albumin concentrations (p<0.001). 30-day mortality was similar between both cohorts (23% and 22%). In cohort 2, age >70 (p<0.05), male gender (p<0.05), COPD (p<0.05), cognitive impairment (p<0.05), frailty (p<0.001), delirium (p = 0.001), CRP>150mg/L (p<0.05), albumin <30 g/L (p<0.01), elevated perioperative Glasgow Prognostic Score (p<0.05), elevated neutrophil-lymphocyte ratio (p<0.001), low haematocrit (p<0.01), elevated PT (p<0.05), sodium <133 mmol/L (p<0.01) elevated urea (p<0.001), creatinine (p<0.001), glucose (p<0.05) and lactate (p<0.001) and the 4C score (p<0.001) were associated with 30-day mortality. In multivariate analysis, greater frailty (CFS>3) (OR 11.3, 95% C.I. 2.3-96.7, p<0.05), low albumin (<30g/L) (OR 2.5, 95% C.I. 1.0-6.2, p<0.05), high NLR (≥3) (OR 2.2, 95% C.I. 1.5-4.5, p<0.05) and the 4C score (OR 2.4, 95% C.I. 1.0-5.6, p<0.05) remained independently associated with 30-day mortality. CONCLUSION: In addition to the 4C mortality score, frailty score and a low albumin were strongly independently associated with 30-day mortality in two consecutive cohorts of patients admitted to hospital with COVID-19. TRIAL REGISTRATION: clinicaltrials.gov: NCT04484545.


Subject(s)
COVID-19 , Hospital Mortality , Hospitalization , SARS-CoV-2/metabolism , Systemic Inflammatory Response Syndrome , Age Factors , Aged , Aged, 80 and over , COVID-19/blood , COVID-19/mortality , COVID-19/therapy , Female , Humans , Male , Middle Aged , Sex Factors , Systemic Inflammatory Response Syndrome/blood , Systemic Inflammatory Response Syndrome/mortality , Systemic Inflammatory Response Syndrome/therapy
4.
Clin Nutr ; 40(5): 2784-2790, 2021 05.
Article in English | MEDLINE | ID: mdl-33933744

ABSTRACT

INTRODUCTION: In coeliac disease (CD) micronutrient deficiencies may occur due to malabsorption in active disease and diminished intake during treatment with a gluten-free diet (GFD). This study assessed the micronutrient status in children with CD at diagnosis and follow-up. METHODS: Fifteen micronutrients were analysed in 106 blood samples from newly diagnosed CD and from patients on a GFD for <6 months, 6-12 months and with longstanding disease (>12 months). Predictors of micronutrient status included: demographics, disease duration, anthropometry, gastrointestinal symptoms, raised tissue transglutaminase antibodies (TGA), multivitamin use and faecal gluten immunogenic peptide (GIP). Micronutrient levels were compared against laboratory reference values. RESULTS: At CD diagnosis (n = 25), low levels in ≥10% of patients were observed for: vitamins E (88%), B1 (71%), D (24%), K (21%), A (20%) and B6 (12%), ferritin (79%), and zinc (33%). One year post-diagnosis, repletion of vitamins E, K, B6 and B1 was observed (<10% patients). In contrast, deficiencies for vitamins D, A and zinc did not change significantly post-diagnosis. Copper, selenium and magnesium did not differ significantly between diagnosis and follow-up. All samples for B2, folate, vitamin C (except for one sample) and B12 were normal. A raised TGA at follow-up was associated with low vitamins A and B1 (raised vs normal TGA; vitamin A: 40% vs 17%, p = 0.044, vitamin B1: 37% vs 13%, p = 0.028). Low vitamin A (p = 0.009) and vitamin D (p = 0.001) were more common in samples collected during winter. There were no associations between micronutrient status with GIP, body mass index, height, socioeconomic status, or gastrointestinal symptom. Multivitamin use was less common in patients with low vitamin D. CONCLUSIONS: Several micronutrient deficiencies in CD respond to a GFD but others need to be monitored long-term and supplemented where indicated.


Subject(s)
Celiac Disease/diet therapy , Micronutrients/deficiency , Adolescent , Celiac Disease/metabolism , Celiac Disease/pathology , Child , Child Nutrition Disorders , Diet, Gluten-Free , Female , Humans , Male , Risk Factors
5.
J Nerv Ment Dis ; 208(8): 600-607, 2020 08.
Article in English | MEDLINE | ID: mdl-32205775

ABSTRACT

This study explores the effects of biopsychosocial factors on life satisfaction among persons with serious mental illness. Participants in this study included a convenience sample of 194 adults recruited from Texas and Wisconsin. A path analysis was conducted with psychiatric symptoms as an exogenous variable, and illness insight, social self-efficacy, social support, community integration, and life satisfaction as endogenous variables. Beginning with a hypothesized model, a best model was obtained after removing the paths that were not significant and adding recommended paths supported by theory. In the final model, psychiatric symptoms, social self-efficacy, social support, and community integration were directly associated with life satisfaction. Illness insight did not directly affect life satisfaction but had indirect effects. Psychiatric symptoms may be the most important and direct predictor of life satisfaction; illness insight, social self-efficacy, social support, and community integration buffer the direct of effect of psychiatric symptoms on life satisfaction.


Subject(s)
Mental Disorders/psychology , Personal Satisfaction , Self Efficacy , Social Support , Adult , Female , Humans , Male , Mental Disorders/therapy , Middle Aged , Models, Psychological , Quality of Life , Severity of Illness Index , Texas , Wisconsin
6.
Clin Nutr ; 39(9): 2824-2831, 2020 09.
Article in English | MEDLINE | ID: mdl-31883613

ABSTRACT

BACKGROUND: Plasma concentrations of most vitamins decrease as part of the systemic inflammatory response (SIR). Thus low plasma values do not necessarily indicate deficiency. Vitamin B6 status is usually assessed by measurement of pyridoxal phosphate (PLP) in plasma, although vitamin concentrations in blood cells tend to be better markers of cellular stores. In health, plasma PLP appears to be determined primarily by intake, its binding to albumin, and its hydrolysis by alkaline phosphatase (ALP). OBJECTIVE: To examine, using in vitro studies, the effect of albumin concentration and ALP activity on PLP concentration in plasma and red blood cells of healthy subjects (HS) and critically ill patients (CI). DESIGN: Heparin and EDTA (ALP inhibited) whole blood samples from HS (n = 8) and CI (n = 26) were incubated with PLP. Concentration of PLP in plasma and red cells was measured. Albumin and ALP levels were determined in plasma. RESULTS: In PLP incubated heparin samples, there was a strong direct relationship between albumin in the concentration range 10-44 g/L and increase in plasma PLP concentration (rs = 0.93, P < 0.001) and an inverse relationship with increase in red cell PLP concentration (rs = -0.90, P < 0.001). In contrast, ALP activity was inversely associated with increase in plasma PLP concentration (rs = -0.42; P = 0.013) and directly associated with red cell PLP concentration (rs = 0.49; P = 0.003). CONCLUSIONS: Plasma albumin concentration and to a lesser extent ALP activity influences PLP concentration in plasma and red cells. In conditions associated with low albumin (e.g. SIR) or altered ALP activity, red cell PLP measurements are more likely to be reliable than plasma measurements in differentiating true from apparent vitamin B6 deficiency and to guide vitamin B6 supplementation.


Subject(s)
Alkaline Phosphatase/blood , Erythrocytes/chemistry , Pyridoxal Phosphate/blood , Serum Albumin/analysis , Vitamin B 6 Deficiency/blood , Vitamin B 6/blood , Adult , Aged , Blood Specimen Collection/methods , Critical Illness , Humans , Inflammation/blood , Middle Aged , Nutritional Status
8.
Ann Clin Biochem ; 54(6): 686-695, 2017 Nov.
Article in English | MEDLINE | ID: mdl-27941128

ABSTRACT

Background Azole-based antifungals are the first-line therapy for some of the most common mycoses and are now also being used prophylactically to protect immunocompromised patients. However, due to variability in both their metabolism and bioavailability, therapeutic drug monitoring is essential to avoid toxicity but still gain maximum efficacy. Methods Following protein precipitation of serum with acetonitrile, 20 µL of extract was injected onto a 2.1 × 50 mm Waters Atlantis dC18 3 µm column. Detection was via a Waters Quattro Premier XE tandem mass spectrometer operating in ESI-positive mode. Multiple reaction monitoring (MRM) detected two product ions for each compound and one for each isotopically labelled internal standard. Ion suppression, linearity, stability, matrix effects, recovery, imprecision, lower limits of measuring interval and detection were all assessed. Results Optimal chromatographic separation was achieved using gradient elution over 8 minutes. Voriconazole, posaconazole and itraconazole eluted at 1.71, 2.73 and 3.41 min, respectively. The lower limits of measuring interval for all three compounds was 0.1 mg/L. The assay was linear to 10 mg/L for voriconazole (R2 = 0.995) and 5 mg/L for posaconazole (R2 = 0.990) and itraconazole (R2 = 0.991). The assay was both highly accurate and precise with % bias of voriconazole, posaconazole and itraconazole, respectively, when compared with previous NEQAS samples. The intra-assay precision (CV%) was 1.6%, 2.5% and 1.9% for voriconazole, posaconazole and itraconazole, respectively, across the linear range. Conclusion A simple and robust method has been validated for azole antifungal therapeutic drug monitoring. This new assay will result in a greatly improved sample turnaround time and will therefore vastly increase the clinical utility of azole antifungal drug monitoring.


Subject(s)
Antifungal Agents/blood , Blood Chemical Analysis/methods , Itraconazole/blood , Tandem Mass Spectrometry , Triazoles/blood , Voriconazole/blood , Chromatography, Liquid , Humans , Reproducibility of Results , Time Factors
9.
Laryngoscope ; 125(6): 1366-71, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25647161

ABSTRACT

OBJECTIVES/HYPOTHESIS: Compare long-term percutaneous endoscopic gastrostomy (PEG) tube dependence, stricture rate, and weight loss in patients receiving a prophylactic gastrostomy tube with those who initially rely on oral intake during chemoradiation for head and neck cancer. Also, to determine what other patient and treatment characteristics influence development of long-term severe dysphagia. STUDY DESIGN: Retrospective review. METHODS: Seventy-nine patients received a PEG tube and 25 did not. The prophylactic and initial oral intake groups were then analyzed to assess the primary outcomes of PEG dependence at last follow-up >1 year. RESULTS: On univariate and multivariate analysis, Zubrod score >1, prophylactic PEG placement, and higher T classification were predicted for PEG tube dependence at last follow-up at least 1 year after treatment. CONCLUSIONS: Prophylactic PEG tube, high Zubrod score, and high T stage were independent predictors for PEG tube dependence at least 1 year after treatment in patients with head and neck cancer receiving definitive chemoradiation. LEVEL OF EVIDENCE: 4.


Subject(s)
Chemoradiotherapy , Gastroscopy , Gastrostomy/methods , Head and Neck Neoplasms/therapy , Deglutition , Female , Gastrostomy/instrumentation , Head and Neck Neoplasms/physiopathology , Humans , Intubation, Gastrointestinal/instrumentation , Male , Middle Aged , Retrospective Studies
10.
J Am Chem Soc ; 135(38): 14276-85, 2013 Sep 25.
Article in English | MEDLINE | ID: mdl-23957439

ABSTRACT

Sphingolipids (SLs) are essential components of cellular membranes formed from the condensation of L-serine and a long-chain acyl thioester. This first step is catalyzed by the pyridoxal-5'-phosphate (PLP)-dependent enzyme serine palmitoyltransferase (SPT) which is a promising therapeutic target. The fungal natural product myriocin is a potent inhibitor of SPT and is widely used to block SL biosynthesis despite a lack of a detailed understanding of its molecular mechanism. By combining spectroscopy, mass spectrometry, X-ray crystallography, and kinetics, we have characterized the molecular details of SPT inhibition by myriocin. Myriocin initially forms an external aldimine with PLP at the active site, and a structure of the resulting co-complex explains its nanomolar affinity for the enzyme. This co-complex then catalytically degrades via an unexpected 'retro-aldol-like' cleavage mechanism to a C18 aldehyde which in turn acts as a suicide inhibitor of SPT by covalent modification of the essential catalytic lysine. This surprising dual mechanism of inhibition rationalizes the extraordinary potency and longevity of myriocin inhibition.


Subject(s)
Fatty Acids, Monounsaturated/chemistry , Serine C-Palmitoyltransferase/antagonists & inhibitors , Crystallography, X-Ray , Kinetics , Mutation , Recombinant Proteins/chemistry , Serine C-Palmitoyltransferase/chemistry , Serine C-Palmitoyltransferase/genetics , Sphingomonas/enzymology , Sphingomonas/genetics
11.
Chem Commun (Camb) ; 49(63): 7058-60, 2013 Aug 14.
Article in English | MEDLINE | ID: mdl-23814788

ABSTRACT

The pyridoxal 5'-phosphate (PLP)-dependent enzyme serine palmitoyltransferase (SPT) is required for de novo sphingolipid biosynthesis. A previous study revealed a novel and unexpected interaction between the hydroxyl group of the l-serine substrate and the 5'-phosphate group of PLP. By using pyridoxal (PL), the dephosphorylated analogue of vitamin B6, we show here that this interaction is important for substrate specificity and optimal catalytic efficiency.


Subject(s)
Pyridoxal Phosphate/metabolism , Serine C-Palmitoyltransferase/metabolism , Biocatalysis , Kinetics , Serine/metabolism , Sphingomonas/enzymology , Substrate Specificity
12.
Work ; 31(3): 337-44, 2008.
Article in English | MEDLINE | ID: mdl-19029675

ABSTRACT

The older population is one of the fastest growing age cohorts in the United States. This population has a higher incidence of disabling conditions than does the younger population. Many older adults may wish to be employed due to economic or personal reasons. This desire to work is consistent with the general older population's perspective on work, however certain barriers to employment exist for this group. Special considerations regarding employment are discussed.


Subject(s)
Aging , Disabled Persons , Employment , Adult , Aged , Aged, 80 and over , Humans , Middle Aged , United States
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