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1.
Clin Gastroenterol Hepatol ; 22(8): 1709-1718.e3, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38518891

ABSTRACT

BACKGROUND & AIMS: Brain-gut behavior therapies (BGBT) are increasingly recognized as effective therapeutic interventions for functional heartburn. However, recommendations regarding candidacy for treatment, initial treatment selection, and navigating treatment non-response have not been established for functional heartburn specifically. The aim of this study was to establish expert-based recommendations for behavioral treatment in patients with functional heartburn. METHODS: The validated RAND/University of California, Los Angeles Appropriateness Method was applied to develop recommendations. A 15-member panel composed of 10 gastrointestinal psychologists and 5 esophageal specialists ranked the appropriateness of a series of statements on a 9-point interval scale over 2 ranking periods. Statements were within the following domains: pre-therapy evaluation, candidacy criteria for BGBT, selection of initial BGBT, role of additional therapy for initial non-response to BGBT, and role of pharmacologic neuromodulation. The primary outcome was appropriateness of each intervention based on the recommendation statements. RESULTS: Recommendations for psychosocial assessment (eg, hypervigilance, symptom-specific anxiety, health-related quality of life), candidacy criteria (eg, motivated for BGBT, acknowledges the role of stress in symptoms), and treatment were established. Gut-directed hypnotherapy or cognitive behavioral therapy were considered appropriate BGBT for functional heartburn. Neuromodulation and/or additional BGBT were considered appropriate in the context of non-response. CONCLUSIONS: Gut-directed hypnotherapy and/or cognitive behavioral therapy are recommended as appropriate behavioral interventions for heartburn symptoms, depending on clinical indication, specific gut-brain targets, and preferred treatment modality (pharmacologic vs non-pharmacologic). Pre-therapy evaluation of psychosocial processes and candidacy for BGBT are important to determine eligibility for referral to psychogastroenterology services.


Subject(s)
Behavior Therapy , Heartburn , Humans , Behavior Therapy/methods , Heartburn/therapy
2.
Chem Sci ; 15(10): 3596-3609, 2024 Mar 06.
Article in English | MEDLINE | ID: mdl-38455019

ABSTRACT

In nature, light-driven water oxidation (WO) catalysis is performed by photosystem II via the delicate interplay of different cofactors positioned in its protein scaffold. Artificial systems for homogeneous photocatalytic WO are based on small molecules that often have limited solubility in aqueous solutions. In this work, we alleviated this issue and present a cobalt-based WO-catalyst containing artificial metalloenzyme (ArM) that is active in light-driven, homogeneous WO catalysis in neutral-pH aqueous solutions. A haem-containing electron transfer protein, cytochrome B5 (CB5), served to host a first-row transition-metal-based WO catalyst, CoSalen (CoIISalen, where H2Salen = N,N'-bis(salicylidene)ethylenediamine), thus producing an ArM capable of driving photocatalytic WO. The CoSalen ArM formed a water-soluble pre-catalyst in the presence of [Ru(bpy)3](ClO4)2 as photosensitizer and Na2S2O8 as the sacrificial electron acceptor, with photocatalytic activity similar to that of free CoSalen. During photocatalysis, the CoSalen-protein interactions were destabilized, and the protein partially unfolded. Rather than forming tens of nanometer sized CoOx nanoparticles as free CoSalen does under photocatalytic WO conditions, the CB5 : CoSalen ArM showed limited protein cross-linking and remained soluble. We conclude that a weak, dynamic interaction between a soluble cobalt species and apoCB5 was formed, which generated a catalytically active adduct during photocatalysis. A detailed analysis was performed on protein stability and decomposition processes during the harsh oxidizing reaction conditions of WO, which will serve for the future design of WO ArMs with improved activity and stability.

3.
J Oncol Pharm Pract ; 30(2): 425-435, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38321882

ABSTRACT

The role of clinical pharmacists or oncology pharmacists in pediatric oncology has been established as important in anticancer regimen review, dose calculation, recommendation, chemocounseling, identification of drug-related problems, its resolution, and, prevention and monitoring of adverse drug reactions within high-income countries. With several hospitals providing pediatric oncology services in Nepal, clinical pharmacist involvement in these hospitals is very poor. Upon reviewing the reputed organization and association focused on pediatric oncology pharmacy practice, it looks imperative for Nepal to initiate clinical pharmacy services which will further help in improving patient health outcomes. As such in this commentary, we try to accentuate the pediatric oncology services and pediatric pharmacy practice within Nepal and try to pinpoint the potential areas for clinical pharmacists to focus if they intend to provide services in pediatric oncology pharmacy practice.


Subject(s)
Neoplasms , Pharmacy Service, Hospital , Pharmacy , Humans , Child , Nepal , Pharmacists
5.
Indian J Gastroenterol ; 43(1): 244-253, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37823984

ABSTRACT

BACKGROUND: Post-traumatic stress (PTS) is the psycho-physiological response to a traumatic or life-threatening event and is implicated in inflammatory bowel disease (IBD). IBD-PTS is present in up to 30% of white, non-Hispanic patients. The rates of IBD in Asian populations are expanding, making the exploration of IBD-PTS in this population imperative. METHODS: Adult patients of South/Southeast (S/SE) Asian decent with IBD for more than 6 months were recruited online via social media and patient-support groups. Participants completed the post-traumatic stress disorder (PTSD) Checklist-5 (PCL-5), the United States National Institutes of Health's Patient-Reported Outcomes Measurement Information System (NIH-PROMIS) -43 profile and demographics. S/SE Asian participants were age and sex matched (1:2) with randomly selected white, non-Hispanic controls. Statistical analyses evaluated differences in IBD-PTS symptoms between groups, the relationship between disease severity and health-related quality of life (HRQoL) and predictors of IBD-PTS severity. RESULTS: Forty-seven per cent of the 51 S/SE Asian participants met the diagnostic cut-off for PTSD on the PCL-5 compared to 13.6% of 110 IBD controls. The mean global score on the PCL-5 was three times higher in S/SE Asians. Patients of S/SE Asian decent were over five times more likely to have PTSD due to their IBD experiences than controls, nearly doubling when controlling for disease activity. More severe IBD-PTS was present in S/SE Asian patients with active disease and those with extraintestinal manifestations. Higher global levels of IBD-PTS were associated with poorer HRQoL in S/SE Asians where increased hyperarousal from IBD-PTS predicted more sleep disturbance. CONCLUSIONS: S/SE Asian patients are five times more likely to experience IBD-PTS than their white, non-Hispanic counterparts. Several cultural factors lead to IBD-PTS in S/SE Asian patients that must be considered by IBD providers. Preventing, screening for and treating IBD-PTS in this population appears warranted.


Subject(s)
Colitis, Ulcerative , Inflammatory Bowel Diseases , Stress Disorders, Post-Traumatic , Adult , Humans , Asian People , Case-Control Studies , Colitis, Ulcerative/complications , Inflammatory Bowel Diseases/complications , Quality of Life , Stress Disorders, Post-Traumatic/etiology , Stress Disorders, Post-Traumatic/complications , United States/epidemiology , White
6.
J Mol Biol ; 436(5): 168407, 2024 03 01.
Article in English | MEDLINE | ID: mdl-38109993

ABSTRACT

Light is required for photosynthesis, but plants are often exposed to excess light, which can lead to photodamage and eventually cell death. To prevent this, they evolved photoprotective feedback mechanisms that regulate photosynthesis and trigger processes that dissipate light energy as heat, called non-photochemical quenching (NPQ). In excess light conditions, the light reaction and activity of Photosystem II (PSII) generates acidification of the thylakoid lumen, which is sensed by special pH-sensitive proteins called Photosystem II Subunit S (PsbS), actuating a photoprotective "switch" in the light-harvesting antenna. Despite its central role in regulating photosynthetic energy conversion, the molecular mechanism of PsbS as well as its interaction with partner proteins are not well understood. This review summarizes the current knowledge on the molecular structure and mechanistic aspects of the light-stress sensor PsbS and addresses open questions and challenges in the field regarding a full understanding of its functional mechanism and role in NPQ.


Subject(s)
Light-Harvesting Protein Complexes , Photosynthesis , Photosystem II Protein Complex , Plants , Light , Light-Harvesting Protein Complexes/chemistry , Photosystem II Protein Complex/chemistry , Plants/enzymology , Protein Conformation
7.
Int J Surg Case Rep ; 109: 108582, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37517259

ABSTRACT

INTRODUCTION: Clear cell sarcoma of the kidney (CCSK) is an uncommon childhood malignancy known for its aggressive behavior and tendency to recur and metastasize to the brain and bones. CASE PRESENTATION: We report a four-year-old boy evaluated for non-specific abdominal pain with an incidental radiological finding of a right lower pole cystic renal mass initially thought to be cystic Wilms' tumor. A pretherapy core biopsy of the mass suggested a clear cell tumor. An open transperitoneal radical nephroureterectomy with aortocaval lymph node sampling was done. Based on histopathological findings and immunohistochemical analysis, CCSK was diagnosed. Appropriate chemotherapy and radiotherapy were instituted postoperatively. At six years follow-up, he was tumor-free and doing well. CLINICAL DISCUSSION: The workup for CCSK includes diagnostic and metastatic imaging, histopathology, and immunohistochemistry analysis. Diagnostic segregation of CCSK and Wilms' tumor is imperative to institute optimal oncological management and improve overall treatment outcomes. CONCLUSION: Considering the age of presentation and clinico-radiological appearance, CCSK can be mistaken for Wilms' tumor, which is much more common in occurrence despite the distinguishable histopathological features, treatment modalities, and prognosis.

8.
Inflamm Bowel Dis ; 29(5): 675-683, 2023 05 02.
Article in English | MEDLINE | ID: mdl-35894686

ABSTRACT

INTRODUCTION: Medical trauma related to IBD (IBD-PTS) affects approximately 25% of patients and is associated with poor outcomes. Prior studies identify common hospitalization experiences as potentially traumatic but have not measured risk relationships for the development of IBD-PTS. We aim to investigate what aspects of hospitalizations may increase the chance of medical trauma and IBD-PTS development. METHODS: Adult patients with IBD enrolled in the IBD Partners database were recruited. Study specific questionnaires included PTSD checklist, 5th edition (PCL-5), patient experience questionnaire, and items about the patient's most stressful hospitalization and nonhospital sources of medical trauma. Established criteria for the PCL-5 identified significant IBD-PTS symptoms (re-experiencing, avoidance, mood change, hyperarousal, global diagnosis). Select disease and treatment information was obtained from the main IBD Partners dataset. Univariate and multivariate statistics evaluated the relationships between hospitalization data and IBD-PTS. RESULTS: There were 639 participants with at least 1 hospitalization for IBD included. Approximately two-thirds had Crohn's disease; most were White, non-Hispanic, female, middle-aged, and reported their IBD as being in remission. Forty percent of patients stated a hospitalization was a source of IBD-PTS. Frequent anxiety while hospitalized increased the odds of IBD-PTS 2 to 4 times; similar relationships existed for pain/pain control. Higher quality communication, information, and listening skills reduced the odds of IBD-PTS, albeit marginally. CONCLUSIONS: Patients with IBD consistently cite hospitalizations as potential sources of medical trauma. Poorly managed anxiety and pain demonstrate the greatest chance for IBD-PTS development. Gender and racial/ethnic differences emerged for these risks. Positive interactions with the medical team may help mitigate in-hospital IBD-PTS development.


This study finds IBD patients with the poorest hospital experiences and those with poor pain and anxiety control are at the highest risk of developing post-traumatic stress disorder symptoms due to medical trauma. Medical staff behavior is an important consideration.


Subject(s)
Crohn Disease , Inflammatory Bowel Diseases , Stress Disorders, Post-Traumatic , Adult , Middle Aged , Humans , Female , Stress Disorders, Post-Traumatic/diagnosis , Inflammatory Bowel Diseases/complications , Hospitalization , Crohn Disease/complications , Pain
9.
Gastroenterol Clin North Am ; 51(4): 785-798, 2022 12.
Article in English | MEDLINE | ID: mdl-36375996

ABSTRACT

Obesity is a prevalent progressive and relapsing disease for which there are several levels of intervention, including metabolic and bariatric surgery (MBS) and now endoscopic bariatric and metabolic therapies (EBMTs). Preoperative psychological assessment focused on cognitive status, psychiatric symptoms, eating disorders, social support, and substance use is useful in optimizing patient outcomes and minimizing risks in MBS. Very little is known about the psychosocial needs of patients seeking EBMTs, though these investigations will be forthcoming if these therapies become more widespread. As MBS and EBMT inherently alter the gastrointestinal (GI) tract, considerations for the longer-term GI functioning of the patient are relevant and should be considered and monitored.


Subject(s)
Bariatric Surgery , Feeding and Eating Disorders , Humans , Obesity/surgery
10.
J Chem Phys ; 157(2): 025101, 2022 Jul 14.
Article in English | MEDLINE | ID: mdl-35840380

ABSTRACT

Photosynthetic light-harvesting complexes have a remarkable capacity to perform robust photo-physics at ambient temperatures and in fluctuating environments. Protein conformational dynamics and membrane mobility are processes that contribute to the light-harvesting efficiencies and control photoprotective responses. This short review describes the application of magic angle spinning nuclear magnetic resonance (NMR) spectroscopy for characterizing the structural dynamics of pigment, protein, and thylakoid membrane components related to light harvesting and photoprotection. I will discuss the use of dynamics-based spectral editing solid-state NMR for distinguishing rigid and mobile components and assessing protein, pigment, and lipid dynamics on sub-nanosecond to millisecond timescales. Dynamic spectral editing NMR has been applied to investigate light-harvesting complex II protein conformational dynamics inside lipid bilayers and in native membranes. Furthermore, we used the NMR approach to assess thylakoid membrane dynamics. Finally, it is shown that dynamics-based spectral editing NMR for reducing spectral complexity by filtering motion-dependent signals enabled us to follow processes in live photosynthetic cells.


Subject(s)
Lipid Bilayers , Tumor Necrosis Factor Ligand Superfamily Member 14 , Light-Harvesting Protein Complexes/chemistry , Lipid Bilayers/chemistry , Magnetic Resonance Spectroscopy/methods , Photosynthesis , Protein Conformation , Tumor Necrosis Factor Ligand Superfamily Member 14/metabolism
11.
Anal Biochem ; 653: 114788, 2022 09 15.
Article in English | MEDLINE | ID: mdl-35732212

ABSTRACT

The introduction of a second coordination sphere, in the form of a protein scaffold, to synthetic catalysts can be beneficial for their reactivity and substrate selectivity. Here we present semi-native polyacrylamide gel electrophoresis (semi-native PAGE) as a rapid screening method for studying metal complex-protein interactions. Such a screening is generally performed using electron spray ionization mass spectrometry (ESI-MS) and/or UV-Vis spectroscopy. Semi-native PAGE analysis has the advantage that it does not rely on spectral changes of the metal complex upon protein interaction and can be applied for high-throughput screening and optimization of complex binding. In semi-native PAGE non-denatured protein samples are loaded on a gel containing sodium dodecyl sulphate (SDS), leading to separation based on differences in structural stability. Semi-native PAGE gel runs of catalyst-protein mixtures were compared to gel runs obtained with native and denaturing PAGE. ESI-MS was additionally realised to confirm protein-complex binding. The general applicability of semi-native PAGE was investigated by screening the binding of various cobalt- and ruthenium-based compounds to three types of haem proteins.


Subject(s)
Hemeproteins , Carrier Proteins , Electrophoresis, Polyacrylamide Gel , Heme , Mass Spectrometry/methods
12.
Angew Chem Int Ed Engl ; 61(14): e202117521, 2022 03 28.
Article in English | MEDLINE | ID: mdl-35103372

ABSTRACT

Non-invasive and real-time recording of processes in living cells has been limited to detection of small cellular components such as soluble proteins and metabolites. Here we report a multiphase NMR approach using magic-angle spinning NMR to synchronously follow microbial processes of fermentation, lipid metabolism and structural dynamic changes in live microalgae cells. Chlamydomonas reinhardtii green algae were highly concentrated, introducing dark fermentation and anoxia conditions. Single-pulse NMR experiments were applied to obtain temperature-dependent kinetic profiles of the formed fermentation products. Through dynamics-based spectral editing NMR, simultaneous conversion of galactolipids into TAG and free fatty acids was observed and rapid loss of rigid lipid structures. This suggests that lipolysis under dark and anoxia conditions finally results in the breakdown of cell and organelle membranes, which could be beneficial for recovery of intracellular microbial useful products.


Subject(s)
Chlamydomonas reinhardtii , Microalgae , Fermentation , Hypoxia , Lipid Metabolism , Magnetic Resonance Spectroscopy , Microalgae/chemistry
13.
Biophys J ; 121(3): 396-409, 2022 02 01.
Article in English | MEDLINE | ID: mdl-34971616

ABSTRACT

The xanthophyll cycle in the antenna of photosynthetic organisms under light stress is one of the most well-known processes in photosynthesis, but its role is not well understood. In the xanthophyll cycle, violaxanthin (Vio) is reversibly transformed to zeaxanthin (Zea) that occupies Vio binding sites of light-harvesting antenna proteins. Higher monomer/trimer ratios of the most abundant light-harvesting protein, the light-harvesting complex II (LHCII), usually occur in Zea accumulating membranes and have been observed in plants after prolonged illumination and during high-light acclimation. We present a combined NMR and coarse-grained simulation study on monomeric LHCII from the npq2 mutant that constitutively binds Zea in the Vio binding pocket. LHCII was isolated from 13C-enriched npq2 Chlamydomonas reinhardtii (Cr) cells and reconstituted in thylakoid lipid membranes. NMR results reveal selective changes in the fold and dynamics of npq2 LHCII compared with the trimeric, wild-type and show that npq2 LHCII contains multiple mono- or digalactosyl diacylglycerol lipids (MGDG and DGDG) that are strongly protein bound. Coarse-grained simulations on npq2 LHCII embedded in a thylakoid lipid membrane agree with these observations. The simulations show that LHCII monomers have more extensive lipid contacts than LHCII trimers and that protein-lipid contacts are influenced by Zea. We propose that both monomerization and Zea binding could have a functional role in modulating membrane fluidity and influence the aggregation and conformational dynamics of LHCII with a likely impact on photoprotection ability.


Subject(s)
Light-Harvesting Protein Complexes , Thylakoids , Light-Harvesting Protein Complexes/chemistry , Photosynthesis , Photosystem II Protein Complex/chemistry , Proteins/metabolism , Thylakoids/metabolism , Zeaxanthins/metabolism
14.
Clin Gastroenterol Hepatol ; 20(6): 1241-1250, 2022 06.
Article in English | MEDLINE | ID: mdl-34364999

ABSTRACT

BACKGROUND & AIMS: Dietary modification is common in patients with digestive diseases to improve symptoms; however, food avoidance can become problematic. Avoidant Restrictive Food Intake Disorder (ARFID) is characterized as failure to meet one's nutritional needs owing to sensory hypersensitivity, lack of interest in eating, or fear of aversive consequences from eating, and is associated with negative medical and psychosocial outcomes. This study characterizes ARFID behaviors in adults with achalasia, celiac sprue, eosinophilic esophagitis, and inflammatory bowel disease. METHODS: In this cross-sectional study, 289 adults aged 18 and older completed self-report measures evaluating use of dietary treatment, ARFID symptoms, and psychosocial outcomes. Primary analyses investigated the occurrence of ARFID in patients with achalasia, celiac, eosinophilic esophagitis, and inflammatory bowel disease. Secondary analyses explored the associations between ARFID symptoms and clinical and psychosocial outcomes. RESULTS: More than half (53.7%) of the total sample met the diagnostic criteria for ARFID based on the Nine-Item ARFID Screen (NIAS), with 78.4% of patients with achalasia meeting criteria. Patients on a physician-directed diet showed greater fear of gastrointestinal symptoms (P = .025), less interest in food (P = .046), and a higher total NIAS score (P = .045). For patients using dietary therapy, those who had met with a dietitian reported higher NIAS scores (P = .039). Food avoidance/restriction was associated with increased anxiety and depression, and diminished health-related quality of life. CONCLUSIONS: It is likely that ARFID rates, as measured by the NIAS, are inflated in these 4 patient groups. These findings highlight the need for updated assessments of ARFID in patients with complex digestive diseases.


Subject(s)
Avoidant Restrictive Food Intake Disorder , Eosinophilic Esophagitis , Esophageal Achalasia , Feeding and Eating Disorders , Gastritis , Inflammatory Bowel Diseases , Adult , Cross-Sectional Studies , Enteritis , Eosinophilia , Humans , Quality of Life , Retrospective Studies
15.
Nat Commun ; 12(1): 2291, 2021 04 16.
Article in English | MEDLINE | ID: mdl-33863895

ABSTRACT

Plants need to protect themselves from excess light, which causes photo-oxidative damage and lowers the efficiency of photosynthesis. Photosystem II subunit S (PsbS) is a pH sensor protein that plays a crucial role in plant photoprotection by detecting thylakoid lumen acidification in excess light conditions via two lumen-faced glutamates. However, how PsbS is activated under low-pH conditions is unknown. To reveal the molecular response of PsbS to low pH, here we perform an NMR, FTIR and 2DIR spectroscopic analysis of Physcomitrella patens PsbS and of the E176Q mutant in which an active glutamate has been replaced. The PsbS response mechanism at low pH involves the concerted action of repositioning of a short amphipathic helix containing E176 facing the lumen and folding of the luminal loop fragment adjacent to E71 to a 310-helix, providing clear evidence of a conformational pH switch. We propose that this concerted mechanism is a shared motif of proteins of the light-harvesting family that may control thylakoid inter-protein interactions driving photoregulatory responses.


Subject(s)
Adaptation, Physiological , Bryopsida/physiology , Light/adverse effects , Photosystem II Protein Complex/metabolism , Stress, Physiological , Bryopsida/radiation effects , Glutamic Acid/genetics , Hydrogen-Ion Concentration/radiation effects , Mutagenesis, Site-Directed , Nuclear Magnetic Resonance, Biomolecular , Photosynthesis/physiology , Photosystem II Protein Complex/genetics , Photosystem II Protein Complex/isolation & purification , Photosystem II Protein Complex/ultrastructure , Protein Conformation, alpha-Helical , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Recombinant Proteins/ultrastructure , Thylakoids/radiation effects
16.
BBA Adv ; 1: 100015, 2021.
Article in English | MEDLINE | ID: mdl-37082020

ABSTRACT

Chloroplast thylakoid membranes in plants and green algae form 3D architectures of stacked granal membranes interconnected by unstacked stroma lamellae. They undergo dynamic structural changes as a response to changing light conditions that involve grana unstacking and lateral supramolecular reorganization of the integral membrane protein complexes. We assessed the dynamics of thylakoid membrane components and addressed how they are affected by thylakoid unstacking, which has consequences for protein mobility and the diffusion of small electron carriers. By a combined nuclear and electron paramagnetic-resonance approach the dynamics of thylakoid lipids was assessed in stacked and cation-depletion induced unstacked thylakoids of Chlamydomonas (C.) reinhardtii. We could distinguish between structural, bulk and annular lipids and determine membrane fluidity at two membrane depths: close to the lipid headgroups and in the lipid bilayer center. Thylakoid unstacking significantly increased the dynamics of bulk and annular lipids in both areas and increased the dynamics of protein helices. The unstacking process was associated with membrane reorganization and loss of long-range ordered Photosystem II- Light-Harvesting Complex II (PSII-LHCII) complexes. The fluorescence lifetime characteristics associated with membrane unstacking are similar to those associated with state transitions in intact C. reinhardtii cells. Our findings could be relevant for understanding the structural and functional implications of thylakoid unstacking that is suggested to take place during several light-induced processes, such as state transitions, photoacclimation, photoinhibition and PSII repair.

17.
Biophys J ; 120(2): 270-283, 2021 01 19.
Article in English | MEDLINE | ID: mdl-33285116

ABSTRACT

Photosynthetic light-harvesting complexes (LHCs) of higher plants, moss, and green algae can undergo dynamic conformational transitions, which have been correlated to their ability to adapt to fluctuations in the light environment. Herein, we demonstrate the application of solid-state NMR spectroscopy on native, heterogeneous thylakoid membranes of Chlamydomonas reinhardtii (Cr) and on Cr light-harvesting complex II (LHCII) in thylakoid lipid bilayers to detect LHCII conformational dynamics in its native membrane environment. We show that membrane-reconstituted LHCII contains selective sites that undergo fast, large-amplitude motions, including the phytol tails of two chlorophylls. Protein plasticity is also observed in the N-terminal stromal loop and in protein fragments facing the lumen, involving sites that stabilize the xanthophyll-cycle carotenoid violaxanthin and the two luteins. The results report on the intrinsic flexibility of LHCII pigment-protein complexes in a membrane environment, revealing putative sites for conformational switching. In thylakoid membranes, fast dynamics of protein and pigment sites is significantly reduced, which suggests that in their native organelle membranes, LHCII complexes are locked in specific conformational states.


Subject(s)
Chlamydomonas reinhardtii , Thylakoids , Chlamydomonas reinhardtii/metabolism , Chlorophyll , Light-Harvesting Protein Complexes/metabolism , Photosynthesis , Photosystem II Protein Complex/metabolism , Thylakoids/metabolism
18.
J Health Commun ; 23(12): 1064-1071, 2018.
Article in English | MEDLINE | ID: mdl-30526400

ABSTRACT

Health systems and insurers alike are increasingly interested in leveraging mHealth (mobile health) tools to support patient health-related behaviors including medication adherence. However, these tools are not widely used by older patients. This study explores patient preferences for functionality in a smartphone application (app) that supports medication self-management among older adults with multiple chronic conditions. We conducted six discussion groups in Chicago, Miami, and Denver (N = 46). English-speaking older adults (55 and older) who owned smartphones and took five or more prescription medicines were invited to participate. Discussions covered familiarity with and use of current apps and challenges with taking multidrug regimens. Participants reviewed a range of possible mobile app functions and were asked to give feedback regarding the acceptability and desirability of each to support medication management. Very few participants (n = 3) reported current use of a mobile app for medication support, although all were receptive. Challenges to medication use were forgetfulness, fear of adverse events, and managing medication information from multiple sources. Desired features included (1) a list and consolidated schedule of medications, (2) identification and warning of unsafe medication interactions, (3) reminder alerts to take medicine, and (4) the ability record when medications were taken. Features relating to refill ordering, pharmacy information, and comparing costs for medication were not considered to be as important for an app.


Subject(s)
Medication Adherence , Mobile Applications , Patient Preference , Self-Management/methods , Aged , Female , Humans , Male , Medication Adherence/psychology , Middle Aged , Smartphone
19.
Med Decis Making ; 38(3): 334-343, 2018 04.
Article in English | MEDLINE | ID: mdl-29436308

ABSTRACT

BACKGROUND: Although there has been increasing interest in patient engagement, few measures are publicly available and suitable for patients with limited health literacy. OBJECTIVE: We sought to develop a Consumer Health Activation Index (CHAI) for use among diverse patients. METHODS: Expert opinion, a systematic literature review, focus groups, and cognitive interviews with patients were used to create and revise a potential set of items. Psychometric testing guided by item response theory was then conducted among 301 English-speaking, community-dwelling adults. This included differential item functioning analyses to evaluate item performance across participant health literacy levels. To determine construct validity, CHAI scores were compared to scales measuring similar personality constructs. Associations between the CHAI and physical and mental health established predictive validity. A second study among 9,478 adults was used to confirm CHAI associations with health outcomes. RESULTS: Exploratory factor analyses revealed a single-factor solution with a 10-item scale. The CHAI showed good internal consistency (alpha = 0.81) and moderate test-retest reliability (ICC = 0.53). Reading grade level was found to be at the 6th grade. Moderate to strong correlations were found with similar constructs (Multidimensional Health Locus of Control, r = 0.38, P < 0.001; Conscientiousness, r = 0.41, P < 0.001). Predictive validity was demonstrated through associations with functional health status measures (depression, r = -0.28, P < 0.001; anxiety, r = -0.22, P < 0.001; and physical functioning, r = 0.22, P < 0.001). In the validation sample, the CHAI was significantly associated with self-reported physical and mental health ( r = 0.31 and 0.32 respectively; both P < 0.001). CONCLUSIONS: The CHAI appears to be a valid, reliable, and easily administered tool that can be used to assess health activation among adults, including those with limited health literacy. Future studies should test the tool in actual use and explore further applications.


Subject(s)
Health Status Indicators , Self Care/instrumentation , Surveys and Questionnaires/standards , Adult , Aged , Factor Analysis, Statistical , Female , Health Status , Humans , Interviews as Topic , Male , Middle Aged , Patient Participation , Psychometrics , Reproducibility of Results
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