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BACKGROUND: The world population is growing rapidly and skin problems such as skin tears (STs) are more common in aging skin due to changes in the epidermis and dermis. Identification of ageing related skin properties, which are risk factors for STs, is essential for the development of ST prevention protocols. OBJECTIVE: The aim of this study was to reveal the skin properties related to epidermal function and dermal associated with STs. MATERIAL AND METHODS: A prospective case-control study was conducted with a sample of 36 older adults, 18 participants with ST and 18 participants without ST, in two elderly care centers. Tewameter TM 210 was used to measure transepidermal water loss, the Sebumeter SM810 was used to measure sebum, and Cutometer Dual MPA 580 was used to measure skin viscoelasticity (R0-R9). The differences of skin properties between groups were analyzed using the independent t-test and Mann-Whitney U test. RESULTS: The case group had a mean age of 77,17 ± 9,7 and the control group had a mean age of 75,33 ± 6,8. It was determined that there were more ecchymosis (p < 0.000), hematoma (p = 0.008), and ST history (p = 0.001) in the case group. Older adults in the case group were more frail than the control group (p = 0.044). Regarding the score of the skin properties, the case group showed that the TEWL levels of the older adults in the case group were lower (p = 0.031) compared to the control groups. There was a significant difference between the groups and R0, R2, R5, and R7. While R0 was higher in the case group, R2, R5, and R7 were lower than the control group. CONCLUSION: Older adults with ST showed differences in skin properties compared to those without ST, especially transepidermal water loss, and viscoelasticity (R0, R2, R5, R7). The results of this study suggest that some changes in skin properties may be a risk factor for STs.
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Envejecimiento de la Piel , Piel , Humanos , Anciano , Recién Nacido , Estudios de Casos y Controles , Epidermis , AguaRESUMEN
The study aimed to establish the reliability and validity of the Turkish version of the Death Depression Scale-Revised (DDS-R) with a sample of 284 nurses. Cronbach's coefficient for the whole scale was .909 and the sub-dimension values were calculated as .934, .798, .715, and .537. The test-retest reliability coefficient was found to be .880. The content validity index (CVI) of the scale was calculated as .86. The results of the exploratory factor analysis showed that 62.254% variance was explained in 4 sub-dimensions of the scale (existential vacuum, death emptiness, other death, death sadness). Confirmatory factor analysis revealed that a four-dimensional structure yielded a good fit (X2/df = 3.124, RMSEA = .087). TDDS-R was found to be a valid and reliable measurement tool in determining the death depression levels of nurses.
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Endobronchial ultrasound (EBUS) has revolutionized the diagnosis of lung cancer over the last decade. This minimally invasive diagnostic method has also become increasingly important in the case of other diseases such as sarcoidosis, thereby helping to avoid unnecessary diagnostic interventions. This review article provides an update regarding EBUS and discusses current and future developments of this method.
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Neoplasias Pulmonares , Sarcoidosis , Ultrasonografía , Broncoscopía , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Ganglios Linfáticos , Sarcoidosis/diagnóstico por imagenRESUMEN
This study was carried out to determine the use of complementary and alternative medicine (CAM) methods by women diagnosed with infertility who had undergone assisted reproduction methods to conceive a child. The study was descriptive and cross-sectional in design. The study was composed of 310 women admitted to the infertility clinic of a Women's and Children's Hospital in Istanbul, Turkey. Data were collected via a questionnaire form that was prepared based on the literature. Data were assessed by percentage calculation. The ratio of CAM use among the women in the study was 51%. The most commonly used practices involved the consumption of onions (65.1%) and figs (45.2%), insertion of sheep tail fat into the vagina (42.9%) and eating walnuts (41.7%). The most commonly known practice was the use of onions (81.9%), followed by figs (56. 3%), amulets (34.1%), parsley (30.67%) and prayers (30.3%). Participants stated that only three methods had been beneficial, with onions (two individuals), diet (one individual), and psychotherapy (one individual), considered as successful practices. Evidence-based studies on the most well-known and practiced methods are needed. Therefore, it is essential to perform meta-analyses and randomized controlled studies.
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Terapias Complementarias/métodos , Infertilidad Femenina/terapia , Adulto , Estudios Transversales , Femenino , Humanos , Encuestas y Cuestionarios , TurquíaRESUMEN
PURPOSE: To assess the effectiveness of reflexology method upon spasticity and function among children with cerebral palsy who received physiotherapy. METHODS: A three group, randomised trial with blinded evaluator. Randomization was made sealed and opaque envelopes. 45 children with cerebral palsy who were trained at a Special Education and Rehabilitation Centre. In the reflexology and placebo group; a 20min reflexology was performed twice a week in a total 24 sessions. In the control group; no intervention was done. Before and after the implementation; measurements of the participants were obtained. The data were collected using Gross Motor Function Measure, Modified Ashworth Scale (MAS), Modified Tardieu Scale, Pediatric Functional Independence Scale, Pediatric Quality of Life Scale (PedsQL) and demographic data. RESULTS: A total of 45 children completed the study. The groups were homogeneous at baseline. Between right MAS Gastrocnemius muscle was a difference and right and left Soleus muscles was significant among the groups (p<0.05). Also; there was significant difference in between right and left Tardieu value in the legs; right M. Gastrocnemius V1,V3 and M. Soleus V1, V3 values; p<0.001 and left Gastrocnemius V1 and M. Soleus V1, V3 values; p<0.001. In Gross Motor Function Measure total scores and sitting position; in Pediatric Functional Independence Scale total scores, self-care and communication subscales (p<0.05). But in terms of PedsQL was no statistically significant difference among the groups (p>0.05). CONCLUSIONS: Reflexology with physiotherapy reduced spasticity in legs, improved gross motor functions, decreased dependency but led to no change in quality of life.
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Parálisis Cerebral/terapia , Masaje/métodos , Espasticidad Muscular/terapia , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Modalidades de Fisioterapia , Recuperación de la FunciónRESUMEN
AIMS AND OBJECTIVES: To examine sexual lives of women with diabetes mellitus (type 2) (DM) and impact of culture on solution for problems related to sexual life. BACKGROUND: DM has long been considered a risk factor for sexual dysfunction in men and women, although the evidence in women is less clear. This study was conducted to emphasise the effect of DM and culture on sexual life. DESIGN: A descriptive and qualitative study. METHODS: Planned as descriptive and qualitative, this study was conducted with 38 women who matched with the following inclusion criterion: living in a neighbourhood with low socio-economic status in the province of Kayseri, Turkey. The Participant Information Form, Diabetes Control Form, the Arizona Sexual Experiences Scale (ASEX), Sexual Life Definition Form and Semi-Structured Interview Form for revealing problems lived in sexual life, besides the results of laboratory tests, were used for data collection. RESULTS: Mean age of the participating women was 51·34 ± 5·85 years. Total score of ASEX was found to be correlated with the type of DM treatment, duration of DM diagnosis, complications of DM, relation with her husband, level of HbA1c and systolic-diastolic blood pressure (p < 0·05). Of the participating women, 47·4% expressed that they had problems with sexual relation. CONCLUSION: Most of the women with DM were determined to have problems in sexual functions besides the disease, and the impact of culture on the solution for problems lived within sexual life was effective. RELEVANCE TO CLINICAL PRACTICE: These findings can help guide to raise the health of Turkish women with diabetes and to plan appropriate nursing interventions.
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Características Culturales , Diabetes Mellitus Tipo 2/fisiopatología , Sexualidad , Femenino , Humanos , Persona de Mediana Edad , Clase Social , TurquíaRESUMEN
Objective: In this study, it was aimed to determine the effect of white noise on anxiety levels and breastfeeding success of primipara mothers having vaginal delivery. Design: The research was conducted using a randomized controlled experimental design. Setting: The research was conducted at a public hospital located in western Turkey. Participants: Sixty primipara mothers, who were between 37 and 42 weeks of gestation, who had a vaginal delivery, and who gave birth to a healthy newborn weighing 2,500-4,000 g, were included in the study as participants. Interventions: The mothers and their babies in the study group (30) were made to listen to white noise with a CD player during breastfeeding in the first hour after delivery and 24 hours after delivery. Measurements: Measurements were performed before, during, and after breastfeeding. A descriptive information form, the State Anxiety Inventory (STAI) Scale, and the "LATCH Breastfeeding Diagnostic and Evaluation Scale" were applied to the mothers by the researcher and the observer. In this way, breastfeeding success and anxiety levels were measured. Results: There was a statistically significant difference between the study group listening to white noise and the control group in terms of the mean STAI-I, observation 2, and observation 4 scores (p < 0.001). Also, it was found that the mean LATCH, observation 1, and observation 2 scores in the control group were significantly lower than the mean LATCH, observation 1, and observation 2 scores in the study group (p < 0.001). Conclusions: As a result of the research, it was determined that white noise was an effective method in increasing breastfeeding success and reducing anxiety levels. In this direction, white noise can be used by health care professionals as a supportive method for breastfeeding.
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Ansiedad , Lactancia Materna , Parto Obstétrico , Madres , Ruido , Humanos , Femenino , Lactancia Materna/psicología , Ansiedad/prevención & control , Adulto , Turquía , Recién Nacido , Madres/psicología , Embarazo , Ruido/efectos adversos , Parto Obstétrico/psicología , ParidadRESUMEN
This descriptive study was designed with a clear focus: to use structural equation modeling to determine the intricate relationships between family sense of coherence, coping, and role performance in parents of children with disabilities. The study was conducted with a sample of 185 parents of children receiving special education at the primary school level in a province in Türkiye. Data was collected using a parent introduction form, the Family Sense of Coherence Scale-short form (FSOC-S), the Family Role Performance (FRP) scale, and the Revised-COPE Scale (R-COPE). The effect of FSOC-S on FRP and R-COPE was statistically significant. The effect of FRP on R-COPE was statistically significant. Moreover, FSOC-S predicted 22.4% of FRP, while FSOC-S and FRP predicted 17.1% of R-COPE. The study's findings underscore the urgent need for interventions to improve the family's sense of coherence and positive coping attitudes. These interventions are crucial for parents to effectively manage the challenges they face while caring for a child with a disability. The study also highlights the significant role of positive coping attitudes and family sense of coherence in enhancing role performance in parents of children with disabilities.
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Chronic Obstructive Pulmonary Disease (COPD) is characterized by progressive and irreversible airflow limitation, with individual body composition influencing disease severity. Severe emphysema worsens symptoms through hyperinflation, which can be relieved by bronchoscopic lung volume reduction (BLVR). To investigate how body composition, assessed through CT scans, impacts outcomes in emphysema patients undergoing BLVR. Fully automated CT-based body composition analysis (BCA) was performed in patients with end-stage emphysema receiving BLVR with valves. Post-interventional muscle and adipose tissues were quantified, body size-adjusted, and compared to baseline parameters. Between January 2015 and December 2022, 300 patients with severe emphysema underwent endobronchial valve treatment. Significant improvements were seen in outcome parameters, which were defined as changes in pulmonary function, physical performance, and quality of life (QoL) post-treatment. Muscle volume remained stable (1.632 vs. 1.635 for muscle bone adjusted ratio (BAR) at baseline and after 6 months respectively), while bone adjusted adipose tissue volumes, especially total and pericardial adipose tissue, showed significant increase (2.86 vs. 3.00 and 0.16 vs. 0.17, respectively). Moderate to strong correlations between bone adjusted muscle volume and weaker correlations between adipose tissue volumes and outcome parameters (pulmonary function, QoL and physical performance) were observed. Particularly after 6-month, bone adjusted muscle volume changes positively corresponded to improved outcomes (ΔForced expiratory volume in 1 s [FEV1], r = 0.440; ΔInspiratory vital capacity [IVC], r = 0.397; Δ6Minute walking distance [6MWD], r = 0.509 and ΔCOPD assessment test [CAT], r = -0.324; all p < 0.001). Group stratification by bone adjusted muscle volume changes revealed that groups with substantial muscle gain experienced a greater clinical benefit in pulmonary function improvements, QoL and physical performance (ΔFEV1%, 5.5 vs. 39.5; ΔIVC%, 4.3 vs. 28.4; Δ6MWDm, 14 vs. 110; ΔCATpts, -2 vs. -3.5 for groups with ΔMuscle, BAR% < -10 vs. > 10, respectively). BCA results among patients divided by the minimal clinically important difference for forced expiratory volume of the first second (FEV1) showed significant differences in bone-adjusted muscle and intramuscular adipose tissue (IMAT) volumes and their respective changes after 6 months (ΔMuscle, BAR% -5 vs. 3.4 and ΔIMAT, BAR% -0.62 vs. 0.60 for groups with ΔFEV1 ≤ 100 mL vs > 100 mL). Altered body composition, especially increased muscle volume, is associated with functional improvements in BLVR-treated patients.
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Enfisema , Enfermedad Pulmonar Obstructiva Crónica , Enfisema Pulmonar , Humanos , Neumonectomía/métodos , Calidad de Vida , Broncoscopía/métodos , Enfisema Pulmonar/diagnóstico por imagen , Enfisema Pulmonar/cirugía , Enfisema Pulmonar/etiología , Enfisema/etiología , Volumen Espiratorio Forzado/fisiología , Composición Corporal , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
BACKGROUND: The coronavirus disease (COVID-19) has greatly affected healthcare workers at the physical and psychosocial level. In this process, primary healthcare workers have taken the most active role by taking part in the filiation groups. OBJECTIVE: This study aimed to determine the anxiety and workload perception level of primary healthcare workers during the COVID-19 pandemic. METHODS: This was a cross-sectional study. An online survey was conducted among 197 healthcare workers. Personal Information Form, the Coronavirus Anxiety Scale and Work Overload Scale were used as data collection tools in the research. Independent Two-Sample T-Test, One-Way Analysis of Variance, Mann-Whitney U test and Kruskal Wallis test were used to evaluate the data. Moreover, the relationships between the scales were evaluated with Pearson correlation analysis and simple regression analysis. RESULTS: The median total score of the Coronavirus Anxiety Scale of healthcare workers was 3.0, and the mean score of the Work Overload Scale was 37.89±7.47. It was found that there was a correlation between the Coronavirus Anxiety and the Work Overload Scales and 21.0% of the variance changes in the Work Overload Scale were affected by coronavirus anxiety. CONCLUSION: It was determined that the level of coronavirus anxiety affects the perception of workload. Therefore, it is recommended that work plans should be made considering this situation.
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COVID-19 , Humanos , COVID-19/epidemiología , Pandemias , SARS-CoV-2 , Estudios Transversales , Personal de Salud/psicología , Ansiedad , Atención Primaria de Salud , Percepción , DepresiónRESUMEN
OBJECTIVE: To examine the age, gender, and chronic disease status of patients who died due to coronavirus disease 2019 (COVID-19) during the pandemic process and the effects of these diseases on their deaths. METHODS: It was a retrospective retrospective analysis with 2715 patients. The statistics of the patients who met the research criteria were evaluated from the hospital database. Patients were evaluated in terms of age, gender, length of hospital stay, presence of chronic disease, and Modified Comorbidity Index Scores. RESULTS: It was determined that the Modified Charlson Comorbidity Index (MCCI) score mean of the patients was 4.74 ± 2.07 and MCCI scores of 56.9% were serious. There was a statistically significant difference in the length of hospital stay according to the number of diseases the patient had, age, and MCCI score. It was determined that there was a statistically significant, negative and high-level correlation between MCCI score and the length of hospital stay (r = -0.075: P = 0.001). CONCLUSIONS: Age, comorbidity score, and the number of comorbidities were found to affect the length of hospital stay, ie death. For this reason, it is recommended to use comorbidity indices in health protection and development studies, in the field, as well as in the clinics.
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COVID-19 , Humanos , Estudios Retrospectivos , COVID-19/epidemiología , Comorbilidad , Enfermedad Crónica , Tiempo de InternaciónRESUMEN
BACKGROUND: Childhood urinary tract infections (UTI) are one of the most important factors affecting adult health. AIM: The study was a cross-sectional investigation to identify the prevalence of UTI and its risk factors. METHODS: The study included 2,511 6-8th grade elementary school students. Data were collected by questionnaire form and medical diagnosis. Descriptive statistics and logistic regression analyses were performed. RESULTS: 7.1% of all participating students had UTI (10.1% girls, 4.2% boys). Students with a family history of UTI had a 3.763-fold risk of developing UTI (p < 0.05) compared to those without. Students who drank <1 liter of water daily had a 1.077 times higher risk of having the infection than those who drank >1 liter of water daily (p < 0.05). CONCLUSION: Students drinking an inadequate amount of water and having a family history had a high prevalence of UTI.
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Estudiantes/estadística & datos numéricos , Infecciones Urinarias/epidemiología , Adolescente , Factores de Edad , Niño , Estudios Transversales , Ingestión de Líquidos , Femenino , Humanos , Modelos Logísticos , Masculino , Oportunidad Relativa , Prevalencia , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Turquía/epidemiologíaRESUMEN
Ips sexdentatus (Coleoptera: Curculionidae) is one of the most destructive pests of the spruce trees in Europe. In this study, we have isolated and characterized culturable bacteria from I. sexdentatus and tested their insecticidal activity against the last instar larvae of the pest as a possible biocontrol agent. A total of eight bacterial isolates was determined and four of them were identified at species level, and the others were identified at genus level. Isolates were identified as Stenotrophomonas maltophilia (Is1), Rahnella sp. (Is2), Pseudomonas sp. (Is3), Bacillus sp. (Is4), Alcaligenes faecalis (Is5), Panteoea agglomerans (Is6), Pseudomonas fluorescens (Is7) and Serratia sp. (Is8) based on their morphological, biochemical and molecular characteristics. Insecticidal effects of bacterial isolates were performed on the last instar larvae of the pest. The highest insecticidal activity was obtained from P. fluorescens (Is7) with 73% mortality within 10 days after inoculation (p < 0.05). Mortality values of the other isolates ranged from 20 to 53%. This study suggests that Pseudomonas fluorescens (Is7) seems to be a good candidate as a possible biocontrol agent against I. sexdentatus, and provides suitable strains that can be modified to express insecticidal toxins and/or other detrimental substances to develop new control methods for I. sexdentatus.
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Bacterias/clasificación , Bacterias/aislamiento & purificación , Gorgojos/microbiología , Animales , Bacterias/genética , Insectos/microbiología , Larva/microbiología , Control Biológico de Vectores/métodos , Filogenia , ARN Ribosómico 16S/genéticaRESUMEN
AIM: Sexual health needs are one of the holistic care needs. Nurses need to help individuals identify and meet these needs. However, sometimes their perception of sexuality can affect their attitudes towards care. The aim of this study determine the effect of sexual self-schema and sexual embarrassment on attitudes and beliefs related to sexual health in nursing students. BACKGROUND: The sexual self-schema, which emphasizes the cognitive aspect of sexuality, is defined as cognitive generalizations that a person does for her/his own sexuality. Sexual self-schemas are known to affect individuals' feelings, beliefs and attitudes towards sexuality. Those with a positive sexual self-schema experience less embarrassment and more positive attitudes towards sexuality. Those with a negative sexual self-schema experience more sexual embarrassment. Those who experience sexual embarrassment have an avoidance of sexual interaction and talking about sexual issues. Nurses and student nurses have embarrassed to talk about sexuality with their patients. It is thought that sexual attitudes and beliefs are effective on this situation. DESIGN: This study was conducted in a cross-sectional descriptive type. Structural equality model was established to test the hypotheses of the research. In the model, the direct effects of the sexual self-schema and the sexual embarrassment on sexual attitudes and beliefs were examined. In addition, the mediating effect of sexual embarrassment between sexual schemas and sexual attitudes and beliefs is also included in the model. METHODS: The study population was the students who attended to and conducted clinical practice at the second, third and fourth study year at a Faculty of Health Sciences. For data collection, the Introductory Information Form which questioned socio-demographic characteristics of individuals, Sexual Self-Schema Scale (SSS), Sexual Embarrassment Scale (SES), and Sexual Attitudes and Beliefs Survey for Sexual Health (SABS) were used. The data were collected online with voluntary participation. RESULTS: Students' average scale scores were: SSS: 121.57 ± 21.23, SES: 12.16 ± 5.74 and SABS: 35.62 ± 7.53. It was also found that sexual self-schemas and sexual embarrassment effected sexual attitudes and beliefs. CONCLUSION: It could be recommended that these results be tested with different studies, that the course content on sexual issues be reviewed be addressed in a broader context.
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Salud Sexual , Estudiantes de Enfermería , Estudios Transversales , Desconcierto , Femenino , Conocimientos, Actitudes y Práctica en Salud , HumanosRESUMEN
The aim of this research was to examine the effect of reflexology on the problems of children with cerebral palsy from perspective of caregivers. Qualitative study was made after 24-session reflexology program. 12 caregivers who have 2-18 year-old children with spastic type cerebral palsy receiving special education and received reflexology. The thematic questions were determined and in-depth interviews were conducted. Themes of the study were determined as; the caregiver's views on reflexology, the effect of reflexology on health of children with CP and the caregivers' observations on child after reflexology therapy, positive and negative aspects and causes of reflexology treatment. As a results; the caregivers expressed that there were increases in self-confidence of children, improvement in walking, reduced spasticity, relaxation, decreases in constipation, and increases in communication, speech and perception after reflexology.
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Cuidadores , Parálisis Cerebral , Masaje , Adolescente , Adulto , Cuidadores/psicología , Cuidadores/estadística & datos numéricos , Parálisis Cerebral/fisiopatología , Parálisis Cerebral/terapia , Niño , Preescolar , Estreñimiento , Humanos , Espasticidad Muscular , CaminataRESUMEN
PURPOSE: Lung cancer accounts for one in five cancer deaths. Broad screening strategies for high-risk populations are unavailable, and the validation of biomarkers for early cancer detection remains a prime interest. Therefore, we investigated the value of circulating U2 small nuclear RNA fragments (RNU2-1f) as a biomarker for diagnosis, prognosis estimation and treatment monitoring in a large lung cancer cohort. METHODS: We determined RNU2-1f abundance in sera of patients with treatment-naive lung cancer (n = 211, 25.6 % early stage), chronic lung disease (n = 56) and healthy controls (n = 58) by reverse transcription quantitative PCR. Initial levels and changes after one chemotherapy cycle were correlated with treatment outcomes in patient subsets. RESULTS: Relative serum RNU2-1f expression levels (REL) were elevated in lung cancer patients compared with patients with chronic lung disease and healthy controls (p < 0.0001). The area under the receiver operating characteristic curve for the complete data set (lung cancer vs. healthy) was 0.91 (95 % CI 0.87-0.95). By applying a REL of -4.505 as diagnostic cutoff (Youden's criterion), sensitivity and specificity reached 0.86 and 0.81, respectively. To determine the generalization error, in a subsampling study, sensitivity and specificity were estimated as 0.82 and 0.77 for the application to future, independent samples. High initial RNU2-1f REL were associated with shorter median survival in stage IIIB/IV disease (RNU2-1fhigh = 228 days/RNU2-1flow = 484 days; p = 0.009, log-rank test, HR1.43 95 % CI 1.23-1.66). Multivariate analysis confirmed RNU2-1f as an independent prognostic factor. Patients with subsequent RNU2-1f reduction had a trend toward better treatment outcome. CONCLUSIONS: Serum RNU2-1f may serve as a biomarker for lung cancer detection, prognosis prediction and treatment monitoring.
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Biomarcadores de Tumor/sangre , Neoplasias Pulmonares/sangre , Neoplasias Pulmonares/diagnóstico , ARN Nuclear Pequeño/sangre , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/sangre , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Carcinoma de Células Pequeñas/sangre , Carcinoma de Células Pequeñas/diagnóstico , Estudios de Casos y Controles , Enfermedad Crónica , Femenino , Alemania/epidemiología , Humanos , Estimación de Kaplan-Meier , Enfermedades Pulmonares/sangre , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Selección de Paciente , Valor Predictivo de las Pruebas , Pronóstico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Riesgo , Sensibilidad y Especificidad , Fumar/efectos adversosRESUMEN
The channel activity of the outer-membrane protein G (OmpG) from Escherichia coli is pH-dependent. To investigate the role of the histidine pair His231/His261 in triggering channel opening and closing, we mutated both histidines to alanines and cysteines. Fourier transform infrared spectra revealed that the OmpG mutants stay-independent of pH-in an open conformation. Temperature ramp experiments indicate that the mutants are as stable as the open state of wild-type OmpG. The X-ray structure of the alanine-substituted OmpG mutant obtained at pH 6.5 confirms the constitutively open conformation. Compared to previous structures of the wild-type protein in the open and closed conformation, the mutant structure shows a difference in the extracellular loop L6 connecting beta-strands S12 and S13. A deletion of amino acids 220-228, which are thought to block the channel at low pH in wild-type OmpG, indicates conformational changes, which might be triggered by His231/His261.