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1.
Palliat Med ; 38(1): 42-56, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38112009

RESUMO

BACKGROUND: Telepalliative care is increasingly used in palliative care, but has yet to be examined from a patient and family perspective. A synthesis of evidence may provide knowledge on how to plan and provide telepalliative care that caters specifically to patients and families' needs. OBJECTIVE: To synthesise evidence on patients and families' perspectives on telepalliative care. DESIGN: A systematic integrative review (PROSPERO #CRD42022301206) reported in accordance with PRISMA 2020 guidelines. Inclusion criteria; primary peer-reviewed studies published 2011-2022, patient and family perspective, >18 years, telepalliative care and English/Danish language. Quality was appraised using the mixed-methods appraisal tool, version 2020. Guided by Toronto and Remington, data were extracted, thematically analysed and synthesised. DATA SOURCES: MEDLINE, EMBASE, PsycINFO and CINAHL were searched in March 2022 and updated in February 2023. RESULTS: Forty-four studies were included. Analysis revealed five themes; the effect of the Covid-19 pandemic on telepalliative care, adding value for patients and families, synchronous and asynchronous telepalliative care, the integration of telepalliative care with other services and the tailoring and timing of telepalliative care. CONCLUSION: Enhanced access to care and convenience, as attributes of telepalliative care, are highly valued. Patients and families have varying needs during the illness trajectory that may be addressed by early integration of telepalliative care based on models of care that are flexible and combine synchronous and asynchronous solutions. Further research should examine telepalliative care in a post-pandemic context, use of models of care and identify meaningful outcome measures from patient and family perspectives for evaluation of telepalliative care.


Assuntos
Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Pandemias , Humanos , Cuidados Paliativos/métodos
2.
Artigo em Inglês | MEDLINE | ID: mdl-36613185

RESUMO

Objectives: To examine patients' and relatives' experiences with participation in an online kidney school (OKS) and its influence on their choice of treatment modality; furthermore, to report on healthcare professionals' (HCPs) first experiences with OKS. Methods: A mixed-methods design with parallel data collection involving two questionnaires for participants, including patients and relatives and a focus group discussion (FGD) with HCPs. Results: The OKS was feasible, and overall, patients and relatives were satisfied. Participation in the OKS increased the percentage of those who felt ready to make a decision regarding treatment. One over-arching theme (evolvement of the online kidney school over time) and three sub-themes (concerns and perceived barriers, facilitators, and benefits and future possibilities) emerged from the FGD. Conclusions: The OKS proved feasible, was well-accepted, and increased participants' abilities to choose a preferred treatment modality. HCPs displayed initial concerns regarding the quality of the OKS and worried about the practicality of conducting the OKS. They experienced a feeling of something being lost. However, over time, HCPs developed strategies to tackle initial concerns and discovered that patients were more capable of participating than they had anticipated.


Assuntos
Pessoal de Saúde , Insuficiência Renal Crônica , Humanos , Estudos de Viabilidade , Insuficiência Renal Crônica/terapia , Inquéritos e Questionários , Rim , Pesquisa Qualitativa
3.
Ugeskr Laeger ; 184(50)2022 12 12.
Artigo em Dinamarquês | MEDLINE | ID: mdl-36510810

RESUMO

INTRODUCTION: Christmas, which is just around the corner, is associated with stress in Danish homes. Therefore, it is important to find interventions that reduce stress levels. Classical music is known to have a soothing effect as it reduces systolic blood pressure and increases quality of life. However, whether or not Christmas music can bring about the same effect is unknown. Therefore, the purpose of this study was to examine whether or not Christmas music has a calming effect. METHODS: The design was a classical intervention study, in which participants were subjected to Christmas music. Blood pressure was measured prior to, and after, the intervention, and a questionnaire was completed regarding demographical questions and questions about one's attitude to Christmas and Christmas spirit. We used a paired t-test to test the primary outcome and a p-value ≤ 0.05 was considered statistically significant. RESULTS: Ten participants took part in the study, of whom 8 were female (and 1 unknown). The systolic blood pressure fell by 3.5 mmHg (p = 0.12) and the Christmas mood which was on an average of 5 at the beginning of the study rose by 0.8 point following the intervention. CONCLUSION: In this study, we displayed that Christmas music has the potential to reduce blood pressure and increase the Christmas spirit. Therefore, we recommend that one plays Christmas music throughout the month of December to reduce stress levels and bring us whole skinned and in high spirits through the Christmas season. FUNDING: none. TRIAL REGISTRATION: none.


Assuntos
Musicoterapia , Música , Humanos , Feminino , Masculino , Qualidade de Vida , Pressão Sanguínea/fisiologia , Ansiedade
4.
Chiropr Man Therap ; 30(1): 57, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36536437

RESUMO

BACKGROUND: Systematic reviews (SRs) of randomized controlled trials (RCTs) are considered one of the most reliable study types. Through a systematic and thorough literature search, researchers aim to collect all research relevant to their purpose. The selection of databases can be challenging and depend on the topic of interest. The Cochrane Handbook suggests searching at least the following three databases: Cochrane Library, MEDLINE, and EMBASE. However, this is not always sufficient for reviews on the musculoskeletal field in general. This study aimed to examine the frequency and choice of databases used by researchers in SRs of spinal manipulative therapy (SMT). Secondly, to analyze the RCTs included in the SRs to determine the optimal combination of databases needed to conduct efficient literature searches for SRs of SMT. METHODS: SRs investigating the effect of SMT on any patient-reported outcome measure were identified through searches in PubMed and Epistemonikos (all entries till date of search February 25, 2022). For each SR, databases searched and included RCTs were collected. RCTs were searched individually in nine databases (Cochrane Library, MEDLINE/PubMed, EMBASE, Google Scholar, CINAHL, Web of Science, Index to Chiropractic Literature, PEDro, and AMED). Coverage rates were calculated using the number of retrieved RCTs by the database or combinations of databases divided by the total number of RCTs. RESULTS: Eighty-five SRs published met the inclusion criteria, and 442 unique RCTs were retrieved. The most frequently searched database was MEDLINE/PubMed. Cochrane Library had the highest overall coverage rate and contained the third most unique RCTs. While a 100% retrieval was not possible, as 18 RCTs could not be retrieved in any of the nine databases, the combination of Cochrane Library, Google Scholar, and PEDro retrieved all possible RCTs with a combined coverage rate of 95.9%. CONCLUSIONS: For SRs on SMT, we recommend using the combination suggested by the Cochrane Handbook of Cochrane Library, MEDLINE/PubMed, Embase, and in addition, PEDro and Index to Chiropractic Literature. Google Scholar might be used additionally as a tool for searching gray literature and quality assurance.


Assuntos
Armazenamento e Recuperação da Informação , Manipulação da Coluna , Humanos , Revisões Sistemáticas como Assunto , MEDLINE , Projetos de Pesquisa
5.
BMJ Open ; 12(7): e061226, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35851005

RESUMO

INTRODUCTION: More than 10% of the population worldwide is affected by chronic kidney disease (CKD). Despite many promising indications regarding the use of mHealth education for patients with CKD, there is still little evidence regarding the feasibility, effectiveness outcomes and outcome measures. Therefore, we will conduct a scoping review to examine the currently available evidence on mHealth education for patients with CKD and, thus, explore the existing evidence regarding feasibility, effectiveness outcomes and outcome measures, patient and/or provider perception and implementation challenges. METHODS AND ANALYSIS: A scoping review will be conducted in accordance with Joanna Briggs Institute Manual for Evidence Synthesis chapter on scoping reviews.MEDLINE, Embase, CINAHL and PsycINFO will be searched. The search strategy will consist of blocks, which have been adopted and modified from former Cochrane reviews. Two independent reviewers will screen studies. Characteristics of the included studies, both quantitative and qualitative, will be reported using quantitative descriptive statistics. Quantitative results will be grouped by objectives (feasibility, effectiveness outcomes and outcome measures, patient perception and implementation challenges), types of intervention and characteristics of participants. Qualitative results will be organised into categories using an iterative process, as suggested by Pollock et al. ETHICS AND DISSEMINATION: As this scoping review does not involve primary data collection, ethical permission is unnecessary. Results of the scoping review will be published in an international peer-reviewed scientific journal. TRIAL REGISTRATION NUMBER: Open Science Framework (https://osf.io/gxkeh/).


Assuntos
Insuficiência Renal Crônica , Telemedicina , Humanos , Avaliação de Resultados em Cuidados de Saúde , Insuficiência Renal Crônica/terapia , Projetos de Pesquisa , Literatura de Revisão como Assunto
6.
BMJ Open ; 12(4): e058728, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35477877

RESUMO

INTRODUCTION: The purpose of the study is to assess the effectiveness of video consultations in patients with type 1 diabetes mellitus (DM) treated with insulin pumps in the outpatient clinic. METHODS AND ANALYSIS: A 52 weeks' duration, open-label, randomised controlled trial will be conducted, enrolling 100 patients with type 1 DM currently treated with insulin pump.Patients will be recruited from the diabetes outpatient clinic at Hospital of Southern Jutland, Department of internal medicine, Sønderborg. Participants will be randomised to either video consultations (experimental intervention) or standard care (control comparator). Participants in the video consultation group will follow their standard care treatment but will have all of their scheduled and non-scheduled appointments by video consultation. The control group will follow their standard care treatment as usual, having all their appointments at the outpatient centre. Primary outcome will be change from baseline of time in range (3.9-10.0 mmol/L). ETHICS AND DISSEMINATION: The study has been approved by the Regional Committe on Health Research Ethics for Southern Denmark, S-20200039G Acadre 20/12922. We will present the results of the trial at international conferences as well as publish the results of the trial in (a) peer-reviewed scientific journal(s). TRIAL REGISTRATION NUMBER: NCT04612933.


Assuntos
Diabetes Mellitus Tipo 1 , Consulta Remota , Instituições de Assistência Ambulatorial , Diabetes Mellitus Tipo 1/tratamento farmacológico , Humanos , Insulina/uso terapêutico , Sistemas de Infusão de Insulina , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Diagnostics (Basel) ; 12(2)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35204554

RESUMO

BACKGROUND: Lanthanum carbonate is a phosphate binder used in advanced kidney disease. Its radiopaque appearance has been described in many case studies and case series. Misinterpretation of this phenomenon leads to unnecessary diagnostic tests and procedures. The objectives of this study were to summarize the literature on lanthanum carbonate opacities and present a visual overview. METHODS: A systematic search was conducted using MEDLINE, Embase, and Web of Science. We included all types of studies, including case reports/studies, describing radiological findings of lanthanum carbonate opacities in patients with chronic kidney disease. No filter for time was set. RESULTS: A total of 36 articles were eligible for data extraction, and 33 articles were included in the narrative synthesis. Lanthanum carbonate opacities were most commonly reported in the intestines (26 studies, 73%), stomach (8 studies, 21%), and the aerodigestive tract (2 studies, 6%). The opacities in the intestine were most frequently described as multiple, scattered radiopaque densities, compared with the aerodigestive tract, where the opacities were described as a single, round foreign body. Suspicion of contrast medium or foreign bodies was the most common differential diagnosis. LC opacities in patients with CKD are commonly misinterpreted as foreign bodies or suspect contrast media. CONCLUSIONS: CKD patients treated with LC may have opacities throughout the digestive tract that can vary in appearance. Stopping LC treatment or changing to an alternative phosphate binder prior to planned image studies can avoid diagnostic confusion. If this is not an option, knowledge of the presentation of LC opacities is important.

8.
BMJ Open ; 12(9): e062723, 2022 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-36688736

RESUMO

INTRODUCTION: Increases in the use of telehealth in palliative care (telepalliative care) prior to, and during, the COVID-19 pandemic have resulted in a proliferation of studies on the topic. While knowledge is building on how providers and recipients adapt to telepalliative care, no reviews have, as of yet, examined telepalliative care from a patient and family perspective. Therefore, the aim of this integrative review is to explore patients and families' perspectives on telepalliative. METHODS AND ANALYSIS: An integrative review will be performed inspired by the methodology of Remmington and Toronto from March 2022 to December 2022. Medline, Embase, PsycINFO and CINAHL will be searched for primary peer-reviewed studies that describe telepalliative care from patient and families' perspectives. Limiters will be used for age; 18 years+, time; 10 years, and language; English and Danish. Hand searches of authors of included articles and reference lists of included articles will be performed. Two reviewers will independently screen and appraise selected articles using the Mixed Method Appraisal Tool. Conflicts will be resolved through discussions with a third reviewer. Data will be extracted independently by two reviewers into a data matrix with predefined headings and analysed using thematic analysis. Findings will be reported thematically, summarised into a thematic synthesis and discussed in relation to relevant literature. ETHICS AND DISSEMINATION: Ethical approval is not required for this review. Results will be published in an international peer-reviewed journal and presented at a relevant international conference. Reporting of this protocol was guided by the Preferred Reporting Items for Systematic reviews and Meta-Analyses Protocol checklist and prospectively reported to PROSPERO (CRD42022301206).


Assuntos
COVID-19 , Enfermagem de Cuidados Paliativos na Terminalidade da Vida , Telemedicina , Humanos , Cuidados Paliativos/métodos , Pandemias , Projetos de Pesquisa , Literatura de Revisão como Assunto
9.
Ugeskr Laeger ; 183(37)2021 09 13.
Artigo em Dinamarquês | MEDLINE | ID: mdl-34596524

RESUMO

This case report describes two 28-year-old healthy males, who werw admitted to hospital due to pain in the lower extremities. Both patients were diagnosed with deep venous thrombosis. In order to determine extent and treatment of the thrombosis, a CT angiography was performed in both patients showing infrarenal vena cava inferior agenesia. Investigation for causes of the thrombosis ruled out cancer and thrombophilia. The patients made full recovery with anticoagulant therapy and compression stockings. Permanent treatment with anticoagulants should be considered in patients with vena cava inferior agenesia.


Assuntos
Trombose Venosa , Anticoagulantes/uso terapêutico , Humanos , Masculino , Meias de Compressão , Veia Cava Inferior/diagnóstico por imagem , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/tratamento farmacológico
10.
Healthcare (Basel) ; 9(6)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207478

RESUMO

Demographical challenges require adaptation and tailoring of services to suit palliative patients' and relatives' needs. Therefore, an interpretive descriptive study was performed to explore patients' and relatives' preferences for the establishment of a day ward and out-of-hours telemedicine. Semi-structured interviews were performed, and data were analysed using thematic analysis. Participants included patients (n = 12) and relatives (n = 5). Three themes emerged: (1) 'Transport burden' relates to transition from home-to-hospital-to-home and acknowledges the strain placed on patients and relatives. (2) 'Role of relatives' contemplates how the role of families in patient care influences patient preferences. (3) 'Telemedicine-preferences and concerns' covers preferences and concerns related to telemedicine in palliative care. The burden of transport and living alone play substantial roles in preferences for place of treatment. Relatives of palliative patients who avail of a day ward and telemedicine may experience an increase in the burden of care. Recognition of concerns pertinent to palliative patients and relatives is an important step in planning new services in palliative care. Concerns may be mitigated by rethinking referral guidelines, incorporating voluntary services, early integration of telemedicine into palliative care and examining patients and relatives' expectations to care, but requires further research.

11.
BMC Med Res Methodol ; 21(1): 94, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33941105

RESUMO

BACKGROUND: Systematic reviews (SRs) are considered one of the most reliable types of studies in evidence-based medicine. SRs rely on a comprehensive and systematic data gathering, including the search of academic literature databases. This study aimed to investigate which combination of databases would result in the highest overall recall rate of references when conducting SRs of qualitative research regarding diabetes mellitus. Furthermore, we aimed to investigate the current use of databases and other sources for data collection. METHODS: Twenty-six SRs (published between 2010 and 2020) of qualitative research regarding diabetes mellitus, located through PubMed, met the inclusion criteria. References of the SRs were systematically hand searched in the six academic literature databases CINAHL, MEDLINE/PubMed, PsycINFO, Embase, Web of Science, and Scopus and the academic search engine Google Scholar. Recall rates were calculated using the total number of included references retrieved by the database or database combination divided by the total number of included references, given in percentage. RESULTS: The SRs searched five databases on average (range two to nine). MEDLINE/PubMed was the most commonly searched database (100% of SRs). In addition to academic databases, 18 of the 26 (69%) SRs hand searched the reference lists of included articles. This technique resulted in a median (IQR) of 2.5 (one to six) more references being included per SR than by database searches alone. 27 (5.4%) references were found only in one of six databases (when Google Scholar was excluded), with CINAHL retrieving the highest number of unique references (n = 15). The combinations of MEDLINE/PubMed and CINAHL (96.4%) and MEDLINE/PubMed, CINAHL, and Embase (98.8%) yielded the highest overall recall rates, with Google Scholar excluded. CONCLUSIONS: We found that the combinations of MEDLINE/PubMed and CINAHL and MEDLINE/PubMed, CINAHL, and Embase yielded the highest overall recall rates of references included in SRs of qualitative research regarding diabetes mellitus. However, other combinations of databases yielded corresponding recall rates and are expected to perform comparably. Google Scholar can be a useful supplement to traditional scientific databases to ensure an optimal and comprehensive retrieval of relevant references.


Assuntos
Diabetes Mellitus , Armazenamento e Recuperação da Informação , Diabetes Mellitus/terapia , Humanos , MEDLINE , Pesquisa Qualitativa , Revisões Sistemáticas como Assunto
12.
Respirol Case Rep ; 9(1): e00695, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33304593

RESUMO

Chylothorax, an uncommon cause of pleural effusion, results from the accumulation of lymph in the pleural space due to damage or obstruction of the thoracic duct. Chylothorax can be due to several aetiologies, many of which are rare, and it is often a diagnostic challenge to identify the cause. This case report refers to a patient with rapid recurrent episodes of bilateral pleural chylothorax due to damage of the thoracic duct after external electrical cardioversion treatment. The diagnosis took place by the method of exclusion, when all known causes of chylothorax, both non-traumatic and traumatic, were ruled out. A review of the literature on chylothorax was performed using PubMed to assess the different aetiologies, investigations, and treatments usually performed. Chylothorax is usually secondary to malignancy, trauma, congenital diseases, and infections. However, even non-invasive thoracic procedures, such as the one described in our case report, can be the cause.

13.
Dermatol Res Pract ; 2020: 8915893, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32099541

RESUMO

BACKGROUND: Atopic dermatitis (AD) is a chronic skin condition where nonadherence often results in lack of disease control. OBJECTIVE: We wanted to determine whether the combination of an electronic memory button and a supportive application (app) would affect the Quality of Life and subjective and objective severity measures among AD patients over one month following the patient's normal schedules of treatment. METHODS: A randomized, investigator-blinded, prospective observational feasibility study for one month where patients diagnosed with AD were randomized based on POEM severity score and divided into 3 groups. The 3 groups were (1) the control group with two consultations, (2) in addition to group 1, patients also received electronic memory buttons to click every time they used their topical products, and (3) in addition to group 2, patients also received an app to track their treatment schedules. At both consultations, patients were evaluated using SCORAD, EASI, POEM, and DLQI. RESULTS: 96 patients were enrolled and randomized, of which 83 patients completed the study. EASI and SCORAD scores were lower in all groups at 2nd consultation (p < 0.05); however, these were highly significant for group 3 (p < 0.05); however, these were highly significant for group 3 (p < 0.05); however, these were highly significant for group 3 (p < 0.05); however, these were highly significant for group 3 (. CONCLUSION: A reduction in severity following objective assessments of the AD was observed for all groups and was highly significant for patients offered a memory button and the corresponding app. Furthermore, patients reported a significant subjective beneficial effect if they used the memory button and app. This indicates that digital solutions may have a benefit in clinical practice and may reduce nonadherence and increase the wellbeing of the patients.

16.
J Interprof Care ; 28(2): 166-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24156733

RESUMO

For the past 20 years, chiropractors have enjoyed access to the Danish health care system and have been free to build integrated health care delivery partnerships. An electronic survey of chiropractic clinics around Denmark was conducted in order to observe interprofessional practice trends. From the available population of 252 practices, 166 responses were received. Ninety-six percent of respondents considered inter-disciplinary/interprofessional practice to be either "very" or "extremely" important in the context of modern Danish health care. Three occupational groups appear to be commonly involved in practice alongside chiropractors, these being massage therapists (82%), physiotherapists (58%) and acupuncturists (37%). Interestingly only 11% considered a medical practitioner to be an active participant in their current interprofessional service delivery. Danish chiropractors consider interprofessional practice to be important and as a group, perceive themselves to be offering such models of service provision. Medical practitioners are perceived as desirable, but under utilized partners.


Assuntos
Atitude do Pessoal de Saúde , Quiroprática , Prestação Integrada de Cuidados de Saúde/organização & administração , Relações Interprofissionais , Atenção Primária à Saúde , Acupuntura , Dinamarca , Humanos , Massagem , Especialidade de Fisioterapia , Inquéritos e Questionários , Recursos Humanos
17.
Biochim Biophys Acta ; 1656(2-3): 156-65, 2004 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-15178477

RESUMO

The membrane-bound proton-pumping inorganic pyrophosphatase from Rhodospirillum rubrum was heterologously expressed in Escherichia coli C43(DE3) cells and was inhibited by 4-bromophenacyl bromide (BPB), N,N'-dicyclohexylcarbodiimid (DCCD), diethyl pyrocarbonate (DEPC) and fluorescein 5'-isothiocyanate (FITC). In each case, the enzyme activity was rather well protected against inhibitory action by the substrate Mg(2)PPi. Site-directed mutagenesis was employed in attempts to identify target residues for these inhibitors. D217 and K469 appear to be the prime targets for DCCD and FITC, respectively, and may thus be involved in substrate binding. No major effect on enzyme activities was seen when any one of the four histidine residues present in the enzyme were substituted. Nevertheless, a mutant with all of the four charged histidine residues replaced retained only less than 10% of the hydrolysis and proton-pumping activities. Substitution of D217 with A or H yielded an enzyme with at least an order of magnitude lower hydrolysis activity. In contrast with the wild-type, these variants showed higher hydrolysis rates at lower concentrations of Mg(2+), possibly reflecting a change in substrate preference from Mg(2)PPi to MgPPi. BPB is a H(+)-pyrophosphatase inhibitor that apparently has not been used previously as an inhibitor of these enzymes.


Assuntos
Escherichia coli/enzimologia , Escherichia coli/metabolismo , Pirofosfatase Inorgânica/antagonistas & inibidores , Fosforilcolina/análogos & derivados , Prótons , Rhodospirillum rubrum/enzimologia , Acetofenonas/farmacologia , Western Blotting , Dicicloexilcarbodi-Imida/farmacologia , Inibidores Enzimáticos/farmacologia , Fluoresceína-5-Isotiocianato/farmacologia , Variação Genética , Histidina/química , Histidina/genética , Histidina/metabolismo , Hidrólise/efeitos dos fármacos , Pirofosfatase Inorgânica/efeitos dos fármacos , Pirofosfatase Inorgânica/genética , Pirofosfatase Inorgânica/metabolismo , Magnésio/metabolismo , Mutagênese Sítio-Dirigida , Mutação , Fosforilcolina/farmacologia , Rhodospirillum rubrum/genética , Especificidade por Substrato
18.
Biochim Biophys Acta ; 1607(2-3): 141-51, 2003 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-14670604

RESUMO

The membrane-bound proton pumping inorganic pyrophosphate synthase/pyrophosphatase (H(+)-PPi synthase/H(+)-PPase) from the photosynthetic bacterium Rhodospirillum rubrum was functionally expressed in Escherichia coli C43(DE3) cells. Based on a new topology model of the enzyme, charged residues predicted to be located near or within the membrane were selected for site-directed mutagenesis. Several of these mutations resulted in an almost complete inactivation of the enzyme. Four mutated residues appear to show a selective impairment of proton translocation and are thus likely to be involved in coupling pyrophosphate hydrolysis with electrogenic proton pumping. Two of these mutations, R176K and E584D, caused increased tolerance to salt. In addition, the former mutation caused an increased K(m) of one order of magnitude for the hydrolysis reaction. These results and their possible implications for the enzyme function are discussed.


Assuntos
Pirofosfatase Inorgânica/genética , Rhodospirillum rubrum/enzimologia , Clonagem Molecular , Escherichia coli/genética , Concentração de Íons de Hidrogênio , Pirofosfatase Inorgânica/metabolismo , Modelos Moleculares , Mutação , Pressão Osmótica , Estrutura Secundária de Proteína , Rhodospirillum rubrum/genética
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