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1.
Physiol Meas ; 43(11)2022 11 03.
Article in English | MEDLINE | ID: mdl-36270506

ABSTRACT

Objectives.Clinical assessment of skin perfusion informs prognosis in critically ill patients. Video camera monitoring could provide an objective, continuous method to monitor skin perfusion. In this prospective, interventional study of healthy volunteers, we tested whether video camera-derived photoplethysmography imaging and colour measurements could detect drug-induced skin perfusion changes.Approach.We monitored the lower limbs of 30 volunteers using video cameras while administering phenylephrine (a vasoconstrictor) and glyceryl trinitrate (a vasodilator). We report relative pixel intensity changes from baseline, as absolute values are sensitive to environmental factors. The primary outcome was the pre- to peak- infusion green channel amplitude change in the pulsatile PPGi waveform component. Secondary outcomes were pre-to-peak changes in the photoplethysmographic imaging waveform baseline, skin colour hue and skin colour saturation.Main results.The 30 participants had a median age of 29 years (IQR 25-34), sixteen (53%) were male. A 34.7% (p= 0.0001) mean decrease in the amplitude of the pulsatile photoplethysmographic imaging waveform occurred following phenylephrine infusion. A 30.7% (p= 0.000004) mean increase occurred following glyceryl trinitrate infusion. The photoplethysmographic imaging baseline decreased with phenylephrine by 2.1% (p= 0.000 02) and increased with glyceryl trinitrate by 0.5% (p= 0.026). Skin colour hue changed in opposite direction with phenylephrine (-0.0013,p= 0.0002) and glyceryl trinitrate (+0.0006,p= 0.019). Skin colour saturation decreased with phenylephrine by 0.0022 (p= 0.0002), with no significant change observed with glyceryl trinitrate (+0.0005,p= 0.21).Significance.Drug-induced vasoconstriction and vasodilation are associated with detectable changes in photoplethysmographic imaging waveform parameters and skin hue. Our findings suggest video cameras have great potential for continuous, contactless skin perfusion monitoring.


Subject(s)
Nitroglycerin , Vasodilation , Humans , Male , Adult , Female , Nitroglycerin/pharmacology , Vasoconstriction , Prospective Studies , Vasodilator Agents/pharmacology , Phenylephrine/pharmacology , Perfusion
2.
BJUI Compass ; 2(2): 126-133, 2021 Mar.
Article in English | MEDLINE | ID: mdl-35474889

ABSTRACT

Objectives: To study high-frequency 29 MHz transrectal side-fire micro-ultrasound (micro-US) for the detection of clinically significant prostate cancer (csPCa) on prostate biopsy, and validate an image interpretation protocol for micro-US imaging of the prostate. Materials and methods: A prospective randomized clinical trial was performed where 1676 men with indications for prostate biopsy and without known prostate cancer were randomized 1:1 to micro-US vs conventional end-fire ultrasound (conv-US) transrectal-guided prostate biopsy across five sites in North America. The trial was split into two phases, before and after training on a micro-US image interpretation protocol that was developed during the trial using data from the pre-training micro-US arm. Investigators received a standardized training program mid-trial, and the post-training micro-US data were used to examine the training effect. Results: Detection of csPCa (the primary outcome) was no better with the first-generation micro-US system than with conv-US in the overall population (34.6% vs 36.6%, respectively, P = .21). Data from the first portion of the trial were, however, used to develop an image interpretation protocol termed PRI-MUS in order to address the lack of understanding of the appearance of cancer under micro-US. Micro-US sensitivity in the post-training group improved to 60.8% from 24.6% (P < .01), while specificity decreased (from 84.2% to 63.2%). Detection of csPCa in the micro-US arm increased by 7% after training (32% to 39%, P < .03), but training instituted mid-trial did not affect the overall results of the comparison between arms. Conclusion: Micro-US provided no clear benefit over conv-US for the detection of csPCa at biopsy. However, it became evident during the trial that training and increasing experience with this novel technology improved the performance of this first-generation system.

4.
Physiol Meas ; 40(6): 06TR01, 2019 07 03.
Article in English | MEDLINE | ID: mdl-31051494

ABSTRACT

OBJECTIVE: Over the last 15 years, developments in camera technology have coincided with increased availability and affordability. This has led to an increasing interest in using these technologies in healthcare settings. Image-based monitoring methods potentially allow multiple vital signs to be measured concurrently using a non-contact sensor. We have undertaken a systematic review of the current availability and performance of these monitoring methods. APPROACH: A multiple database search was conducted using MEDLINE, Embase, CINAHL, Cochrane Library, OpenGrey, IEEE Xplore Library and ACM Digital Library to July 2018. We included studies comparing image-based heart rate, respiratory rate, oxygen saturation and blood pressure monitoring methods against one or more validated reference device(s). Each included study was assessed using the modified GRRAS criteria for reporting bias. MAIN RESULTS: Of 30 279 identified studies, 161 were included in the final analysis. Twenty studies (20/161, 12%) were carried out on patients in clinical settings, while the remainder were conducted in academic settings using healthy volunteer populations. The 18-40 age group was best represented across the identified studies. One hundred and twenty studies (120/161, 75%) estimated heart rate, followed by 62 studies (62/161, 39%) estimating respiratory rate. Fewer studies focused on oxygen saturation (11/161, 7%) or blood pressure (6/161, 4%) estimation. Fifty-one heart rate studies (51/120, 43%) and 24 respiratory rate studies (24/62, 39%) used Bland-Altman analysis to report their results. Of the heart rate studies, 28 studies (28/51, 55%) showed agreement within industry standards of [Formula: see text]5 beats per minute. Only two studies achieved this within clinical settings. Of the respiratory rate studies, 13 studies (13/24, 54%) showed agreement within industry standards of [Formula: see text]3 breaths per minute, but only one study achieved this in a clinical setting. Statistical analysis was heterogeneous across studies with frequent inappropriate use of correlation. The majority of studies (99/161, 61%) monitored subjects for under 5 min. Three studies (3/161, 2%) monitored subjects for over 60 min, all of which were conducted in hospital settings. SIGNIFICANCE: Heart rate and respiratory rate monitoring using video images is currently possible and performs within clinically acceptable limits under experimental conditions. Camera-derived estimates were less accurate in the proportion of studies conducted in clinical settings. We would encourage thorough reporting of the population studied, details of clinically relevant aspects of methodology, and the use of appropriate statistical methods in future studies. Systematic review registration: PROSPERO CRD42016029167 Protocol: https://systematicreviewsjournal.biomedcentral.com/articles/10.1186/s13643-017-0615-3.


Subject(s)
Blood Pressure/physiology , Heart Rate/physiology , Image Processing, Computer-Assisted , Monitoring, Physiologic , Oxygen/metabolism , Respiratory Rate/physiology , Adolescent , Adult , Ethnicity , Female , Geography , Humans , Infant, Newborn , Male , Partial Pressure , Skin Pigmentation , Vital Signs , Young Adult
5.
Anaesthesia ; 74(8): 1018-1025, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31066046

ABSTRACT

Excessive noise in hospitals adversely affects patients' sleep and recovery, causes stress and fatigue in staff and hampers communication. The World Health Organization suggests sound levels should be limited to 35 decibels. This is probably unachievable in intensive care units, but some reduction from current levels should be possible. A preliminary step would be to identify principal sources of noise. As part of a larger project investigating techniques to reduce environmental noise, we installed a microphone array system in one with four beds in an adult general intensive care unit. This continuously measured locations and sound pressure levels of noise sources. This report summarises results recorded over one year. Data were collected between 7 April 2017 and 16 April 2018 inclusive. Data for a whole day were available for 248 days. The sound location system revealed that the majority of loud sounds originated from extremely limited areas, very close to patients' ears. This proximity maximises the adverse effects of high environmental noise levels for patients. Some of this was likely to be appropriate communication between the patient, their caring staff and visitors. However, a significant proportion of loud sounds may originate from equipment alarms which are sited at the bedside. A redesign of the intensive care unit environment to move alarm sounds away from the bed-side might significantly reduce the environmental noise burden to patients.


Subject(s)
Intensive Care Units , Noise , Humans , Noise/adverse effects , Sound
6.
Diabet Med ; 36(1): 52-61, 2019 01.
Article in English | MEDLINE | ID: mdl-30343489

ABSTRACT

AIMS: To evaluate the effectiveness of automated symptom and side effect monitoring on quality of life among individuals with symptomatic diabetic peripheral neuropathy. METHODS: We conducted a pragmatic, cluster randomized controlled trial (July 2014 to July 2016) within a large healthcare system. We randomized 1834 primary care physicians and prospectively recruited from their lists 1270 individuals with neuropathy who were newly prescribed medications for their symptoms. Intervention participants received automated telephone-based symptom and side effect monitoring with physician feedback over 6 months. The control group received usual care plus three non-interactive diabetes educational calls. Our primary outcomes were quality of life (EQ-5D) and select symptoms (e.g. pain) measured 4-8 weeks after starting medication and again 8 months after baseline. Process outcomes included receiving a clinically effective dose and communication between individuals with neuropathy and their primary care provider over 12 months. Interviewers collecting outcome data were blinded to intervention assignment. RESULTS: Some 1252 participants completed the baseline measures [mean age (sd): 67 (11.7), 53% female, 57% white, 8% Asian, 13% black, 20% Hispanic]. In total, 1179 participants (93%) completed follow-up (619 control, 560 intervention). Quality of life scores (intervention: 0.658 ± 0.094; control: 0.653 ± 0.092) and symptom severity were similar at baseline. The intervention had no effect on primary [EQ-5D: -0.002 (95% CI -0.01, 0.01), P = 0.623; pain: 0.295 (-0.75, 1.34), P = 0.579; sleep disruption: 0.342 (-0.18, 0.86), P = 0.196; lower extremity functioning: -0.079 (-1.27, 1.11), P = 0.896; depression: -0.462 (-1.24, 0.32); P = 0.247] or process outcomes. CONCLUSIONS: Automated telephone monitoring and feedback alone were not effective at improving quality of life or symptoms for people with symptomatic diabetic peripheral neuropathy. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02056431).


Subject(s)
Diabetic Neuropathies/therapy , Monitoring, Physiologic/methods , Primary Health Care , Quality of Life , Aged , Cluster Analysis , Diabetic Neuropathies/physiopathology , Diabetic Neuropathies/psychology , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Practice Patterns, Physicians'
7.
Anaesthesia ; 74(1): 100-108, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30291744

ABSTRACT

Quality of life after critical illness is becoming increasingly important as survival improves. Various measures have been used to study the quality of life of patients discharged from intensive care. We systematically reviewed validated measures of quality of life and their results. We searched PubMed, CENTRAL, CINAHL, Web of Science and Open Grey for studies of quality of life, measured after discharge from intensive care. We categorised studied populations as: general; restricted to level-3 care or critical care beyond 5 days; and septic patients. We included quality of life measured at any time after hospital discharge. We identified 48 studies. Thirty-one studies used the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) and 19 used the EuroQol-5D (EQ-5D); eight used both and nine used alternative validated measures. Follow-up rates ranged from 26-100%. Quality of life after critical care was worse than for age- and sex-matched populations. Quality of life improved for one year after hospital discharge. The aspects of life that improved most were physical function, physical role, vitality and social function. However, these domains were also the least likely to recover to population norms as they were more profoundly affected by critical illness.


Subject(s)
Critical Care/psychology , Patient Discharge , Quality of Life , Critical Illness , Humans , Intensive Care Units , Sepsis/psychology , Sepsis/therapy
8.
HIV Med ; 20(1): 27-32, 2019 01.
Article in English | MEDLINE | ID: mdl-30402918

ABSTRACT

OBJECTIVES: People living with HIV (PLWH) are at increased risk of asymptomatic neurosyphilis; thus, it has been common practice to perform a lumbar puncture (LP) in all PLWH presenting with syphilis regardless of stage, signs or symptoms. However, this practice varies widely among clinicians. Our objective was to elucidate the number of LPs required to diagnose a single case of asymptomatic neurosyphilis. METHODS: We performed an electronic health record (EHR) review of PLWH who were diagnosed with syphilis of any stage over a 10-year period. EHRs were reviewed to determine the number of subjects who had an LP performed, what proportion had neurological signs or symptoms, and whether a diagnosis of neurosyphilis was made at presentation or follow-up. RESULTS: In 261 separate episodes of syphilis in 230 subjects, we found the major risk factors for asymptomatic neurosyphilis to be low CD4 T-cell count (P = 0.0007), high rapid plasma reagin (RPR) titre (P = 0.019) and lack of HIV virological suppression (P = 0.003). The majority of our subjects (78%) with neurosyphilis presented with central nervous system (CNS) symptoms. We estimate, if standard practice is to perform LP in all patients, that the number needed to test (NNTT) = 38. CONCLUSIONS: This large number of potentially unnecessary LPs, along with heterogeneity of presentation, and the never-nil risk of asymptomatic neurosyphilis should be incorporated into clinical decision-making. The majority of PLWH presenting with a serological diagnosis of syphilis, but no neurological signs or symptoms, do not necessarily require an LP for an evaluation of asymptomatic neurosyphilis.


Subject(s)
HIV Infections/microbiology , Neurosyphilis/diagnosis , Reagins/blood , Adult , Aged , Aged, 80 and over , CD4 Lymphocyte Count , Clinical Decision-Making , Electronic Health Records , Female , HIV Infections/immunology , Humans , Male , Middle Aged , Neurosyphilis/immunology , Neurosyphilis/pathology , Retrospective Studies , Spinal Puncture/statistics & numerical data , Transgender Persons , Young Adult
9.
Int J Obes (Lond) ; 42(2): 231-243, 2018 02.
Article in English | MEDLINE | ID: mdl-28630461

ABSTRACT

BACKGROUND: Obesity is associated with gut microbiota dysbiosis, disrupted intestinal barrier and chronic inflammation. Given the high and increasing prevalence of obesity worldwide, anti-obesity treatments that are safe, effective and widely available would be beneficial. We examined whether the medicinal mushroom Antrodia cinnamomea may reduce obesity in mice fed with a high-fat diet (HFD). METHODS: Male C57BL/6J mice were fed a HFD for 8 weeks to induce obesity and chronic inflammation. The mice were treated with a water extract of A. cinnamomea (WEAC), and body weight, fat accumulation, inflammation markers, insulin sensitivity and the gut microbiota were monitored. RESULTS: After 8 weeks, the mean body weight of HFD-fed mice was 39.8±1.2 g compared with 35.8±1.3 g for the HFD+1% WEAC group, corresponding to a reduction of 4 g or 10% of body weight (P<0.0001). WEAC supplementation reduced fat accumulation and serum triglycerides in a statistically significant manner in HFD-fed mice. WEAC also reversed the effects of HFD on inflammation markers (interleukin-1ß, interleukin-6, tumor necrosis factor-α), insulin resistance and adipokine production (leptin and adiponectin). Notably, WEAC increased the expression of intestinal tight junctions (zonula occludens-1 and occludin) and antimicrobial proteins (Reg3g and lysozyme C) in the small intestine, leading to reduced blood endotoxemia. Finally, WEAC modulated the composition of the gut microbiota, reducing the Firmicutes/Bacteroidetes ratio and increasing the level of Akkermansia muciniphila and other bacterial species associated with anti-inflammatory properties. CONCLUSIONS: Supplementation with A. cinnamomea produces anti-obesogenic, anti-inflammatory and antidiabetic effects in HFD-fed mice by maintaining intestinal integrity and modulating the gut microbiota.


Subject(s)
Antrodia/chemistry , Diet, High-Fat , Dysbiosis/diet therapy , Gastrointestinal Microbiome/drug effects , Inflammation/diet therapy , Obesity/diet therapy , Plant Extracts/pharmacology , Plants, Medicinal/chemistry , Animals , Disease Models, Animal , Dysbiosis/physiopathology , Insulin Resistance/physiology , Male , Medicine, Traditional , Mice , Mice, Inbred C57BL , Obesity/physiopathology
10.
HIV Med ; 18(10): 756-763, 2017 11.
Article in English | MEDLINE | ID: mdl-28585361

ABSTRACT

OBJECTIVES: The aim of the study was to determine the prevalence of transmitted drug resistance (TDR)-associated mutations among treatment-naïve, incarcerated individuals with HIV-1 infection in the USA as well as the class TDR and antiretroviral (ARV) mutations present at baseline. METHODS: Patients over the age of 18 years were included in the study if they had been diagnosed with HIV infection, if their HIV infection was managed through telemedicine and if they were incarcerated in the State of Illinois Department of Corrections between 10 July 2010 and 29 April 2016. Additionally, the patients were required to have a documented genotype and be ARV-naïve. A medical chart review was conducted to assess demographic information, disease burden, and risk factors for acquiring the virus. RESULTS: The inclusion criteria were met for 105 patients. A total of 24 patients (23%) had a clinically significant mutation associated with resistance to any drug class. The prevalence of mutations conferring clinically significant resistance was 19% for nonnucleoside reverse transcriptase inhibitors (NNRTIs), 18% for nucleoside reverse transcriptase inhibitors (NRTIs), and 4% for protease inhibitors (PIs). Five per cent of patients had dual-class TDR to both NRTI and NNRTI drug classes and 2% of patients had mutations to both NNRTI and PI drug classes. There was no significant increase in the prevalence of clinically relevant drug resistance mutations based on demographics, burden of disease, or risk factors for acquiring the virus. CONCLUSIONS: A high prevalence of TDR was identified in the ARV-naïve incarcerated population. The results of this study indicate an increased prevalence of TDR in a largely unstudied incarcerated population, demonstrating the need for increased monitoring of resistance in HIV-infected patients world-wide.


Subject(s)
Drug Resistance, Viral , HIV Infections/transmission , HIV Infections/virology , HIV-1/drug effects , Prisoners , Adult , Disease Transmission, Infectious , Female , Genotype , HIV-1/isolation & purification , Humans , Male , Middle Aged , Mutation , Prevalence , Retrospective Studies , United States/epidemiology , Young Adult
11.
Faraday Discuss ; 194: 709-729, 2016 12 16.
Article in English | MEDLINE | ID: mdl-27711798

ABSTRACT

Ultrafast time-resolved ion yield (TR-IY) and velocity map imaging spectroscopies are employed to reveal the relaxation dynamics after photoexcitation in ethyl 4-hydroxy-3-methoxycinnamate (ethyl ferulate, EF), an active ingredient in commercially available sunscreens. In keeping with a bottom-up strategy, the building blocks of EF, 2-methoxy-4-vinylphenol (MVP) and 4-hydroxy-3-methoxycinnamyl alcohol (coniferyl alcohol, ConA), were also studied to assist in our understanding of the dynamics of EF as we build up in molecular complexity. In contrast to the excited state dynamics of MVP and ConA, which are described by a single time constant (>900 ps), the dynamics of EF are described by three time constants (15 ± 4 ps, 148 ± 47 ps, and >900 ps). A mechanism is proposed involving internal conversion (IC) between the initially excited S1(11ππ*) and S2(11nπ*) states followed by intramolecular vibrational redistribution (IVR) on both states, in competition with intersystem crossing onto neighbouring triplet states (15 ± 4 ps). IVR and IC within the triplet manifold then ensues (148 ± 47 ps) to populate a low-lying triplet state (>900 ps). Importantly, the fluorescence spectrum of EF at the S1 origin, along with the associated lifetime (6.9 ± 0.1 ns), suggests that population is trapped, during initial IVR, on the S1(11ππ*) state. This serves to demonstrate the complex, competing dynamics in this sunscreen filter molecule.

12.
Oncogene ; 35(7): 856-66, 2016 Feb 18.
Article in English | MEDLINE | ID: mdl-26119936

ABSTRACT

The tumor suppressor serine/threonine kinase 11 (STK11 or LKB1) is mutated in 20-30% of patients with non-small-cell lung cancer (NSCLC). Loss of LKB1-adenosine monophosphate-activated protein kinase (AMPK) signaling confers sensitivity to metabolic inhibition or stress-induced mitochondrial insults. We tested the hypothesis that loss of LKB1 sensitizes NSCLC cells to energetic stress induced by treatment with erlotinib. LKB1-deficient cells exhibited enhanced sensitivity to erlotinib in vitro and in vivo that was associated with alterations in energy metabolism and mitochondrial dysfunction. Loss of LKB1 expression altered the cellular response to erlotinib treatment, resulting in impaired ATP homeostasis and an increase in reactive oxygen species. Furthermore, erlotinib selectively blocked mammalian target of rapamycin signaling, inhibited cell growth and activated apoptosis in LKB1-deficient cells. Erlotinib treatment also induced AMPK activation despite loss of LKB1 expression, which was partially reduced by the application of a calcium/calmodulin-dependent protein kinase kinase 2 inhibitor (STO-609) or calcium chelator (BAPTA-AM). These findings may have significant implications for the design of novel NSCLC treatments that target dysregulated metabolic and signaling pathways in LKB1-deficient tumors.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Non-Small-Cell Lung/genetics , Erlotinib Hydrochloride/pharmacology , Lung Neoplasms/genetics , Protein Serine-Threonine Kinases/genetics , AMP-Activated Protein Kinase Kinases , Animals , Blotting, Western , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Drug Resistance, Neoplasm , Energy Metabolism/drug effects , Female , Flow Cytometry , Gene Knockdown Techniques , Humans , Lung Neoplasms/metabolism , Mice , Mice, Nude , Mutation , RNA, Small Interfering , Signal Transduction/drug effects , Signal Transduction/physiology , Transfection , Xenograft Model Antitumor Assays
13.
J Hosp Infect ; 92(2): 173-7, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26616410

ABSTRACT

BACKGROUND: Considering the incidence and severity of Clostridium difficile infection (CDI), risk reduction strategies are crucial. Prior studies suggest that proton pump inhibitor (PPI) use can increase the risk of CDI over antibiotics alone; however, data and guidelines have been conflicting. AIM: The aim was to compare CDI incidence in patients receiving high-risk antibiotics, comparing rates in those prescribed a PPI versus those without overlapping PPI exposure. METHODS: This retrospective cohort study assessed the incidence of CDI in veterans receiving high-risk antibiotics over an approximately three-year period. High-risk antibiotics were defined as: ciprofloxacin, levofloxacin, moxifloxacin, clindamycin, ceftriaxone, cefotaxime, ceftazidime, or cefixime. FINDINGS: We identified subjects who were prescribed any high-risk antibiotic, finding 3513 on a concomitant PPI and 6149 not taking a PPI. Of these subjects, 111 were diagnosed with CDI and met inclusion criteria. Baseline characteristics, CDI severity, length of hospitalization and antibiotic therapy prior to infection were similar in both groups. The incidence of CDI was significantly higher in patients prescribed a PPI (odds ratio: 2.2; 95% confidence interval: 1.52-3.23; P=0.0001). A strong association was found between concurrent PPI use with fluoroquinolones (P=0.005) and clindamycin (P=0.045). CONCLUSION: The use of PPIs together with high-risk antibiotics was associated with a significantly higher incidence of CDI. Our study provides further support for the CDI prevention strategy of judicious PPI use, especially in patients receiving high-risk antibiotics. Prudent avoidance of PPIs may reduce the incidence of CDI, a major cause of morbidity and mortality worldwide.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Clostridioides difficile/isolation & purification , Clostridium Infections/epidemiology , Cross Infection/epidemiology , Diarrhea/epidemiology , Proton Pump Inhibitors/administration & dosage , Adolescent , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/adverse effects , Clostridioides difficile/classification , Clostridioides difficile/genetics , Clostridium Infections/microbiology , Cross Infection/microbiology , Diarrhea/microbiology , Female , Humans , Incidence , Male , Middle Aged , Proton Pump Inhibitors/adverse effects , Retrospective Studies , Risk Assessment , Young Adult
14.
J Phys Chem A ; 119(50): 12131-7, 2015 Dec 17.
Article in English | MEDLINE | ID: mdl-26299435

ABSTRACT

The time-resolved photofragmentation dynamics of 4-tert-butylcatechol were studied following one photon excitation to the S1 (1(1)ππ*) state with ultraviolet radiation in the range 260 ≤ λ ≤ 286 nm. The preparation of an aligned molecular ensemble via photoexcitation leads to anisotropy in the H atom photofragments. These H atoms originate from the decay of the S1 state through coupling onto the S2 ((1)πσ*) state, which is dissociative along the nonintramolecular hydrogen bonded "free" O-H bond. The degree of anisotropy of these photogenerated H atoms decreases with increasing pump-probe time delay. This is attributed to rotational dephasing of the initially aligned molecular ensemble. The measured dephasing occurs on a time scale akin to the appearance time of these H atoms, which likely places an intrinsic lower bound on the dephasing lifetime. The present work demonstrates how a careful balance between the appearance time of the H atoms, determined by the S1 lifetime, and the rotational dephasing in 4-tert-butylcatechol provides an opportune window to probe rotational motion in real time.

15.
Phys Rev Lett ; 114(23): 233001, 2015 Jun 12.
Article in English | MEDLINE | ID: mdl-26196796

ABSTRACT

The ability to probe energy flow in molecules, following the absorption of ultraviolet light, is crucial to unraveling photophysical phenomena. Here we excite a coherent superposition of vibrational states in the first excited electronic state (S1) in catechol, resulting in a vibrational wave packet. The observed quantum beats, assigned to superpositions of the low-frequency, and strongly mixed, O-H torsional mode τ2, elegantly demonstrate how changes in geometry upon photoionization from the S1 state to the ground state of the cation (D0) enables one to probe energy flow at the very early stages of photoexcitation in this biological chromophore.

16.
Intensive Care Med ; 41(9): 1549-60, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25952825

ABSTRACT

PURPOSE: To determine whether early goal-directed therapy (EGDT) reduces mortality compared with other resuscitation strategies for patients presenting to the emergency department (ED) with septic shock. METHODS: Using a search strategy of PubMed, EmBase and CENTRAL, we selected all relevant randomised clinical trials published from January 2000 to January 2015. We translated non-English papers and contacted authors as necessary. Our primary analysis generated a pooled odds ratio (OR) from a fixed-effect model. Sensitivity analyses explored the effect of including non-ED studies, adjusting for study quality, and conducting a random-effects model. Secondary outcomes included organ support and hospital and ICU length of stay. RESULTS: From 2395 initially eligible abstracts, five randomised clinical trials (n = 4735 patients) met all criteria and generally scored high for quality except for lack of blinding. There was no effect on the primary mortality outcome (EGDT: 23.2% [495/2134] versus control: 22.4% [582/2601]; pooled OR 1.01 [95% CI 0.88-1.16], P = 0.9, with heterogeneity [I(2) = 57%; P = 0.055]). The pooled estimate of 90-day mortality from the three recent multicentre studies (n = 4063) also showed no difference [pooled OR 0.99 (95% CI 0.86-1.15), P = 0.93] with no heterogeneity (I(2) = 0.0%; P = 0.97). EGDT increased vasopressor use (OR 1.25 [95% CI 1.10-1.41]; P < 0.001) and ICU admission [OR 2.19 (95% CI 1.82-2.65); P < 0.001]. Including six non-ED randomised trials increased heterogeneity (I(2) = 71%; P < 0.001) but did not change overall results [pooled OR 0.94 (95% CI 0.82 to 1.07); P = 0.33]. CONCLUSION: EGDT is not superior to usual care for ED patients with septic shock but is associated with increased utilisation of ICU resources.


Subject(s)
Shock, Septic/therapy , Critical Care/methods , Early Medical Intervention , Goals , Humans , Randomized Controlled Trials as Topic , Shock, Septic/mortality
17.
Health Technol Assess ; 17(38): v-vi, 1-87, 2013 Sep.
Article in English | MEDLINE | ID: mdl-24028755

ABSTRACT

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a major cause of mortality in intensive care patients and lacks effective treatments. A previous randomised controlled Phase II trial suggested that an intravenous (i.v.) infusion of salbutamol may be beneficial, as it reduced extravascular lung water and plateau airway pressure. The Beta-Agonist Lung injury TrIal-2 (BALTI-2) was initiated to evaluate the effects of this intervention on mortality in patients with ARDS. OBJECTIVES: To evaluate whether or not, in patients with ARDS, an i.v. infusion of salbutamol given at 15 µg/kg ideal body weight (IBW)/hour for up to 7 days, compared with a placebo (0.9% sodium chloride) infusion, reduces 28-day all-cause mortality and other clinical outcomes. To evaluate salbutamol's clinical effectiveness and its cost-effectiveness in subgroups of patients. DESIGN: A multicentre, randomised, placebo-controlled trial. SETTING: Forty-six intensive care units (ICUs) in the UK. PARTICIPANTS: Patients were eligible if they (1) were intubated and mechanically ventilated patients in participating ICUs; (2) were within 72 hours of onset of ARDS; (3) fulfilled American-European Consensus Conference definition for ARDS {acute-onset, severe hypoxaemic respiratory failure [partial pressure of oxygen in arterial blood/fraction of inspired oxygen ≤ 26.7 kPa (200 mmHg)] and bilateral infiltrates on the chest radiograph in the absence of clinical evidence of left atrial hypertension}; and (4) were aged ≥ 16 years. INTERVENTIONS: Intravenous infusion of salbutamol (15 µg/kg IBW/hour) or placebo (0.9% saline) for up to 7 days. MAIN OUTCOME MEASURES: All-cause mortality 28 days after randomisation, mortality at (first) discharge from ICU, mortality at (first) discharge from hospital, number of ventilator-free days, number of organ failure-free days, mortality at 12 months post randomisation, side effects (tachycardia/new arrhythmia/lactic acidosis) sufficient to stop treatment with trial drug, health-related quality of life (European Quality of Life-5 Dimensions and Short Form questionnaire-12 items at 6 and 12 months after randomisation), length of stay in critical care unit and length of stay in hospital. RESULTS: Forty-six ICUs recruited patients to the trial. A total of 326 patients were randomised; 162 were allocated to salbutamol and 164 to placebo. One patient in each group withdrew consent. Recruitment was stopped after the second interim analysis because of safety concerns. Salbutamol increased 28-day mortality: 55 (34%) of 161 patients died in the salbutamol group compared with 38 (23%) of 163 in the placebo group (risk ratio 1.47, 95% confidence interval 1.03 to 2.08). CONCLUSIONS: Treatment with i.v. salbutamol early in the course of ARDS was poorly tolerated, is unlikely to be beneficial and could worsen outcomes. Further trials of ß-agonists in patients with ARDS are unlikely to be conducted. Some questions remain, such as whether or not there may be benefit at a different dose or in specific populations, but any studies investigating these would require a very strong rationale. TRIAL REGISTRATION: Current Controlled Trials ISRCTN38366450. FUNDING: The National Institute for Health Research Health Technology Assessment programme.


Subject(s)
Adrenergic beta-2 Receptor Agonists/therapeutic use , Albuterol/therapeutic use , Respiratory Distress Syndrome/drug therapy , APACHE , Adolescent , Adrenergic beta-2 Receptor Agonists/adverse effects , Adrenergic beta-2 Receptor Agonists/economics , Adult , Age Factors , Aged , Aged, 80 and over , Albuterol/adverse effects , Albuterol/economics , Cost-Benefit Analysis , Double-Blind Method , Female , Hospital Mortality , Humans , Infusions, Intravenous , Intensive Care Units/statistics & numerical data , Length of Stay , Male , Middle Aged , Respiration, Artificial , Respiratory Distress Syndrome/mortality , United Kingdom , Young Adult
18.
Colorectal Dis ; 15(4): e190-8, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23331871

ABSTRACT

AIM: Our aim was to determine the frequency and economic impact of anastomotic leakage (AL) at local and national levels in England. METHOD: All patients who underwent AR in Oxford between 2007 and 2009 were evaluated for AL. Hospital Episode Statistics (HES) data were used to determine reoperation rates after elective AR (n = 23 388) in England between 2000 and 2008. Hospital episode remuneration costs were calculated by the local commissioning department and compared with Department of Health (DH) reference index costs. RESULTS: The frequency of AL following anterior resection was 10.9% (31 out of 285) in Oxford. Laparotomy for leakage was performed in 5.6% of cases. The 30-day hospital mortality rate for all ARs was 2.1%, compared with 3.2% after AL. The national relaparotomy rate (within 28 days) and 30-day hospital mortality in English National Health Service (NHS) trusts following AR were 5.9% and 2.9%, respectively. Institutional remunerated tariffs (£6233 (SD ± 965)) were similar to DH reference costs (£6319 (SD ± 1830)) after uncomplicated AR. However, there was a significant (P = 0.008) discrepancy between the remunerated tariff for AL (£9605 (SD ± 6908)) and the actual cost (£17 220 (SD ± 9642)). AL resulted in an additional annual cost of approximately £1.1 million to £3.5 million when extrapolated nationally. CONCLUSION: The estimated economic burden of anastomotic leakage following AR is approximately double that of the remunerated tariff.


Subject(s)
Adenocarcinoma/surgery , Adenoma/surgery , Anastomotic Leak/economics , Anastomotic Leak/therapy , Hospital Costs/statistics & numerical data , Insurance, Health, Reimbursement/economics , Rectal Neoplasms/surgery , State Medicine/economics , Aged , England , Enterostomy/economics , Female , Hospital Mortality , Humans , Male , Middle Aged , Reoperation/economics
19.
Cell Death Dis ; 3: e361, 2012 Aug 09.
Article in English | MEDLINE | ID: mdl-22874998

ABSTRACT

Recent observations indicate prostatic diseases are comorbidities of systemic metabolic dysfunction. These discoveries revealed fundamental questions regarding the nature of prostate metabolism. We previously showed that prostate-specific ablation of PPARγ in mice resulted in tumorigenesis and active autophagy. Here, we demonstrate control of overlapping and distinct aspects of prostate epithelial metabolism by ectopic expression of individual PPARγ isoforms in PPARγ knockout prostate epithelial cells. Expression and activation of either PPARγ 1 or 2 reduced de novo lipogenesis and oxidative stress and mediated a switch from glucose to fatty acid oxidation through regulation of genes including Pdk4, Fabp4, Lpl, Acot1 and Cd36. Differential effects of PPARγ isoforms included decreased basal cell differentiation, Scd1 expression and triglyceride fatty acid desaturation and increased tumorigenicity by PPARγ1. In contrast, PPARγ2 expression significantly increased basal cell differentiation, Scd1 expression and AR expression and responsiveness. Finally, in confirmation of in vitro data, a PPARγ agonist versus high-fat diet (HFD) regimen in vivo confirmed that PPARγ agonization increased prostatic differentiation markers, whereas HFD downregulated PPARγ-regulated genes and decreased prostate differentiation. These data provide a rationale for pursuing a fundamental metabolic understanding of changes to glucose and fatty acid metabolism in benign and malignant prostatic diseases associated with systemic metabolic stress.


Subject(s)
Epithelial Cells/cytology , Metabolic Networks and Pathways , PPAR gamma/metabolism , Animals , Cell Differentiation/drug effects , Cell Line , Cell Transformation, Neoplastic , Diet, High-Fat , Down-Regulation , Epithelial Cells/metabolism , Fatty Acids/metabolism , Gene Expression Regulation/drug effects , Gene Knockout Techniques , Glucose/metabolism , Lipogenesis , Male , Mice , Oxidative Stress , PPAR gamma/agonists , PPAR gamma/genetics , Prostate/cytology , Protein Isoforms/genetics , Protein Isoforms/metabolism , Stearoyl-CoA Desaturase/metabolism , Thiazolidinediones/pharmacology
20.
QJM ; 103(4): 243-51, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20139102

ABSTRACT

BACKGROUND: Delirium is an acute organ dysfunction common amongst patients treated in intensive care units. The associated morbidity and mortality are known to be substantial. Previous surveys have described which screening tools are used to diagnose delirium and which medications are used to treat delirium, but these data are not available for the United Kingdom. AIM: This survey aimed to describe the UK management of delirium by consultant intensivists. Additionally, knowledge and attitudes towards management of delirium were sought. The results will inform future research in this area. METHODS: A national postal survey of members of the UK Intensive Care Society was performed. A concise two page questionnaire survey was sent, with a second round of surveys sent to non-respondents after 6 weeks. The questionnaire was in tick-box format. RESULTS: Six hundred and eighty-one replies were received from 1308 questionnaires sent, giving a response rate of 52%. Twenty-five percent of respondents routinely screen for delirium, but of these only 55% use a screening tool validated for use in intensive care. The majority (80%) of those using a validated instrument used the Confusion Assessment Method for the Intensive Care Unit. Hyperactive delirium is treated pharmacologically by 95%; hypoactive delirium is treated pharmacologically by 25%, with haloperidol the most common agent used in both. Over 80% of respondents agreed that delirium prolongs mechanical ventilation and hospital stay and requires active treatment. CONCLUSION: This UK survey demonstrates screening for delirium is sporadic. Pharmacological treatment is usually with haloperidol in spite of the limited evidence to support this practice. Hypoactive delirium is infrequently treated pharmacologically.


Subject(s)
Delirium/drug therapy , Delivery of Health Care/standards , Intensive Care Units/standards , Antipsychotic Agents/therapeutic use , Delirium/diagnosis , Haloperidol/therapeutic use , Humans , Surveys and Questionnaires , United Kingdom
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