Post-operative pain after single-visit root canal treatment using resin-based and bioceramic sealers in teeth with apical periodontitis: A randomised controlled-trial.

The present study aimed to compare postoperative pain in teeth with symptomatic and asymptomatic apical periodontitis (AP) following a single-visit endodontic treatment using BioRoot™ RCS or AH Plus at 8 h, 24 h and 48 h postoperatively. Postgraduate students performed endodontic treatment on 101 teeth with AP, randomised into two obturation groups. A 100-mm Visual Analog Scale was used to document the intensity of pain at preoperative, 8-h, 24-h and 48-h intervals. The Kolmogorov-Smirnov test was used for normality, and the median and interquartile ranges were compared using the Mann-Whitney U test. Preoperative pain (1.90 ± 3.50) was more frequent in teeth with symptomatic AP (p < 0.05). However, no significant differences were observed in postoperative pain at the 8-h, 24-h and 48-h intervals. Pre and postoperative pain were directly associated (p < 0.05). Single-visit root canal treatment in teeth with AP using both sealers resulted in similar levels of postoperative pain.

Degree of satisfaction of women treated with reconstruction and dermopigmentation of the nipple-areola complex after breast reconstruction.

OBJECTIVE: To evaluate the degree of satisfaction of women treated with dermopigmentation and reconstruction of the Areola-Nipple Complex (ANC) after breast reconstruction, as well as their demographic profile and clinical-evolutionary characteristics. METHODS: Descriptive observational study including 128 women treated with dermopigmentation after oncologic breast reconstruction during 2018. In 2021 they were administered an adapted satisfaction questionnaire, which contains 27 items and categorizes satisfaction from 1-5, in addition other clinical-evolutionary and demographic variables were collected. RESULTS: Mean age was 51 (±9) years, 89.1% had previously undergone PDA reconstruction. Mean satisfaction with dermopigmentation was 4.4 (±0.88) and 3.79 (±1.06) for PDA reconstruction. Complications were rare, but 54.5% (n = 54) of the patients reported that the CAP reconstruction did not offer the expected projection, 91.6% (n = 98) that the color had faded and 51.4% (n = 55) would choose permanent tattooing. It was perceived that, the higher the satisfaction of the CAP, the higher the satisfaction of dermopigmentation, while the older the age and previous chemotherapy treatment the lower the color durability (p value ≤ 0.05). CONCLUSIONS: Patients who underwent reconstructive breast surgery show a high degree of satisfaction with dermopigmentation and surgical reconstruction of the PDA, but reiterate the low projecticity of the dermopigmentation and the surgical reconstruction of the PDA, but reiterate the low degree of satisfaction with the dermopigmentation.

Outcome of Nonsurgical Root Canal Retreatment Procedures Obturated with Warm Gutta-percha Techniques: A Longitudinal Clinical Study.

INTRODUCTION: To evaluate the success rate of nonsurgical root canal retreatment at the 2-3-year follow-up and identify the possible prognostic factors. METHODS: Patients who underwent root canal retreatment at a university dental clinic were contacted for clinical and radiographic follow-up. The retreatment outcomes in these cases were based on clinical signs, symptoms, and radiographic criteria. Inter- and intraexaminer concordances were calculated using Cohen's kappa coefficient. The retreatment outcome was dichotomized into success or failure according to strict and loose criteria. The radiographic success criteria consisted of complete resolution or absence of a periapical lesion (strict criteria) or a reduction in the size of an existing periapical lesion at recall (loose criteria). χ2 tests were used to evaluate possible variables associated with retreatment outcomes (age, sex, tooth type, location, contact points, periapical status, quality of previous and final root canal filling, previous and final restoration, number of visits, and complications). RESULTS: Overall, 129 teeth (113 patients) were included in the final evaluation. The success rate was 80.6% under strict criteria and 93% under loose criteria. Molars, teeth with an initially higher periapical index score, and teeth with >5 mm periapical radiolucency had a lower success rate according to the strict criteria model (P < .05). When the loose success criteria were used, teeth with larger (>5 mm) periapical lesions and those that had been perforated during retreatment showed a lower success rate (P < .05). CONCLUSIONS: The present study demonstrated that nonsurgical root canal retreatment is a highly successful procedure after an observation period of 2-3 years. Treatment success is primarily affected by the presence of large periapical lesions.

Satisfaction of intensive care unit patients linked to clinical and organisational factors: A cross-sectional multicentre study.

BACKGROUND: The satisfaction of critical care patients with the nursing care they receive is a key indicator of the quality of hospital care. OBJECTIVES: The objectives of this study were to analyse the level of satisfaction of critical care patients in relation to the nursing care received and to determine the relationship between the level of satisfaction and sociodemographic, clinical, and organisational variables. DESIGN: This was a prospective, descriptive correlational study. SETTING AND METHODS: The population consisted of all patients discharged from the intensive care units (ICUs) of 19 hospitals in Spain between December 2018 and December 2019. The level of satisfaction was measured using the validated Nursing Intensive Care Satisfaction Scale, and sociodemographic, clinical, and organisational data were collected. RESULTS: Participants' mean age (n = 677) was 59.7 (standard deviation: 16.1), and 62.8% of them were men (n = 426). Satisfaction with the nursing care received was 5.66 (SD: 0.68) out of a possible 6. The score for overall satisfaction presented statistically significant relationships with the hours of mechanical ventilation (p = 0.034), with the participant's perception of own health status (p = 0.01), with the participant's perceived degree of own recovery (p = 0.01), with the hospital's complexity level (p = 0.002), with the type of hospital (p = 0.005), and with the type of ICU (p = 0.004). Finally, the logistic regression model shows that the Nursing Intensive Care Satisfaction Scale score was not linked to age or sex but did have a statistically significant relationship with the perceived degree of recovery (p < 0.001) and the type of ICU (p=<0.001). The variables that predicted satisfaction were age, degree of recovery, and the type of ICU. CONCLUSION: Several studies show that patient satisfaction is related to the patient's perceived health status and perceived degree of recovery, a finding that is confirmed in our study. Our study moves beyond these outcomes to show that the hours of mechanical ventilation and the characteristics of the hospital also have a significant relationship with patients' satisfaction.

[Effect of the forward head syndrome in the development of temporomandibular disorders]. / Efecto del síndrome de cabeza adelantada en el desarrollo de trastornos temporomandibulares.

Bad habits, such as poor posture during the use of technological devices, poor abdominal control and oral breathing pattern can lead to a forward head position, which has important implications for the entire future of the individual, especially at the stomatognathic system. There is a strong association between temporomandibular disorders and forward head syndrome. Where the muscular component is the main affected, with the appearance of more trigger points at the level of the sternocleidomastoid muscles, upper trapezius, rectus capitis posterior and upper oblique capitis. Degenerative changes in the temporomandibular joint have been observed, but evidence is still lacking to ensure that Forward Head Syndrome is the etiological factor.

Impact of dysphagia and malnutrition on the survival of hospitalized patients.

INTRODUCTION: Oropharyngeal dysphagia (OD) and malnutrition (MN) are highly prevalent among hospitalized patients, with significant clinical repercussions. OBJECTIVES: To assess the prevalence, survival and factors associated with OD and MN in hospitalized patients with a high risk of OD. METHODS: A cross-sectional observational study with 82 patients aged ≥70 years and with the possibility of oral feeding admitted in 4 services of a third level hospital during 3 months. The Nutritional Risk Screening 2002 test (NRS-2002) was performed to detect nutritional risk and the volume-viscosity screening test (V-VST) for OD evaluation. Data were collected on the clinical suspicion of OD, days of hospital stay, the number of readmissions and other socio-demographic data. RESULTS: 50.6% had OD and 51.9% MN. In 48.8%, there was underdiagnosis of OD. The median number of days of admission was higher among patients with MN (19.5 days vs 13 days, p = 0.02). Of the total readmissions, 70.8% had MN compared to 29.2% that did not (p = 0.03). Survival among patients who did not survive one year after admission was lower when OD was given (Sig. = 0.04). CONCLUSIONS: More than half of the population studied has OD, as well as DN, which increases the rate of readmission and decreases survival at the year of admission. Although there are specific screening methods, their use is not widespread, making it difficult to diagnose OD and its therapeutic intervention.

[Standardized nursing languages and care plans. Perception of use and utility in primary healthcare]. / Lenguajes enfermeros estandarizados y planes de cuidados. Percepción de su empleo y utilidad en atención primaria.

OBJECTIVE: To identify opinions of Primary Healthcare nurses on the use and usefulness of standardised nursing care plans and traditional nursing language systems in the practice settings. DESIGN: Multicentre, observational, cross-sectional study. SETTING: Primary Healthcare centres in Catalonia. PARTICIPANTS: Sample size was estimated at 1,668 registered nurses. Consecutive sampling was applied. INTERVENTIONS: On-line survey containing questions on ease, usefulness, and use of nursing care plans and standardised nursing language systems. MEASUREMENTS: Descriptive statistics, including percentages, central tendency, and dispersion measures. Statistical significance was set at P≤.05. RESULTS: The final analysis included 1,813 questionnaires. Participants stated that care plans have a medium added value, however their use is frequently incorrect. They stated to have a fair level of knowledge on traditional standardised nursing languages, and most were of the opinion that these languages are difficult to use in practice (81%) and not useful to represent nursing care provision and its outcomes (78%). Regardless of their education level and years of experience, the participants assessed as insufficient the clarity (P=.058), ease of use (P=.240), and usefulness (P=.039) of these language systems in practice. CONCLUSIONS: Nurses say that urgent changes are required in the use of care plans. This includes changing the language systems, and improving data and information that positively impacts on the provision of nursing care, as well as to enhance the health outcomes of the individuals receiving Primary Healthcare services.

Accuracy and completeness of records of adverse events through interface terminology. / Precisión y exhaustividad del registro de eventos adversos mediante una terminología de interfase.

OBJECTIVE: To determine what adverse events, including pressure ulcers, infection of the surgical site and aspiration pneumonia, nurses record in clinical histories, in terms of diagnostic accuracy and completeness, through ATIC. METHOD: Observational, descriptive, cross-sectional, multicenter study of 64 medical-surgical and semi-critical units of two university hospitals in Catalonia, Spain, during 2015. The diagnostic accuracy was assessed by means of the correspondence between the event declared in the Minimum Basic Data Set and the problem documented by the nurse. The record was considered complete when it contained the risk of the event, prescriptions of care and a record of the evolution. RESULTS: The sample evaluated included 459 records. The accuracy results of pressure ulcers are highly correlated between the nursing diagnosis recorded and that declared in the Minimum Basic Data Set. The accuracy in surgical site infection is moderate, and aspiration resulting in pneumonia is very low. The completeness of results is remarkable, except for the risk of bronchoaspiration. CONCLUSION: The adverse event recorded by nurses with greatest accuracy is pressure ulcers.

Precisión y exhaustividad del registro de eventos adversos mediante una terminología de interfase / Precisão e exaustividade no registro de eventos adversos usando uma terminologia de interface / Accuracy and completeness of records of adverse events through interface terminology

RESUMEN Objetivo: Determinar qué registran las enfermeras en la historia clínica mediante ATIC, sobre los eventos adversos: úlceras por presión, infección del sitio quirúrgico y aspiración con resultado de neumonía, en términos de precisión diagnostica y exhaustividad. Método: Estudio observacional, descriptivo, transversal, y multicéntrico de 64 unidades médico-quirúrgicas y semicríticos de dos hospitales universitarios de Cataluña, España, durante el año 2015. La precisión diagnóstica se evaluó mediante la correspondencia entre el evento declarado en el Conjunto Mínimo Básico de Datos y el problema documentado por la enfermera. La exhaustividad se consideró cuando el registro contenía el riesgo del evento, prescripciones de cuidados y registro de la evolución. Resultados: La muestra evaluada fue de 459 registros. Los resultados de precisión de úlceras por presión muestran una elevada correspondencia entre el diagnóstico enfermero registrado y el declarado en el Conjunto Mínimo Básico de Datos. La precisión en la infección del sitio quirúrgico es moderada, y la aspiración con resultado de neumonía muy baja. Los resultados de exhaustividad son notables, excepto el riesgo de broncoaspiración. Conclusión: El evento adverso que registran las enfermeras con mayor precisión es la úlcera por presión.

RESUMO Objetivo: Determinar quais informações são registradas pelas enfermeiras nos registros eletrônicos por meio da terminologia ATIC, sobre os eventos adversos: úlceras de pressão, infecção de sítio cirúrgico e aspiração com resultado de pneumonia, em termos de precisão diagnóstica e de exaustividade. Método: Estudo observacional, descritivo, transversal e multicêntrico de 64 unidades médico cirúrgicas e semicríticas de dois hospitais universitários da Catalunha, Espanha, durante o ano 2015. A precisão diagnóstica foi avaliada pela correspondência entre o evento indicado no Conjunto Mínimo Básico de Dados e o registro de problemas documentados pela enfermeira. A exaustividade foi considerada quando o registro continha a identificação do risco do evento, as prescrições de cuidados e o registro da evolução. Resultados: A amostra avaliada foi de 459 registros. Os resultados em termos de precisão de úlceras de pressão mostram uma alta correlação entre o diagnóstico de enfermagem registrado e o diagnóstico declarado no Conjunto Mínimo Básico de Dados. A precisão na infecção de sítio cirúrgico é moderada, e a aspiração com resultado de pneumonia é muito baixa. Os resultados de exaustividade são notáveis, salvo o risco de broncoaspiração. Conclusão: O evento adverso que as enfermeiras registram com maior precisão é a úlcera de pressão.

ABSTRACT Objective: To determine what adverse events, including pressure ulcers, infection of the surgical site and aspiration pneumonia, nurses record in clinical histories, in terms of diagnostic accuracy and completeness, through ATIC. Method: Observational, descriptive, cross-sectional, multicenter study of 64 medical-surgical and semi-critical units of two university hospitals in Catalonia, Spain, during 2015. The diagnostic accuracy was assessed by means of the correspondence between the event declared in the Minimum Basic Data Set and the problem documented by the nurse. The record was considered complete when it contained the risk of the event, prescriptions of care and a record of the evolution. Results: The sample evaluated included 459 records. The accuracy results of pressure ulcers are highly correlated between the nursing diagnosis recorded and that declared in the Minimum Basic Data Set. The accuracy in surgical site infection is moderate, and aspiration resulting in pneumonia is very low. The completeness of results is remarkable, except for the risk of bronchoaspiration. Conclusion: The adverse event recorded by nurses with greatest accuracy is pressure ulcers.

Surveillance nursing diagnoses, ongoing assessment and outcomes on in-patients who suffered a cardiorespiratory arrest.

Objective The purposes of this study were to examine the frequency of surveillance-oriented nursing diagnoses and interventions documented in the electronic care plans of patients who experienced a cardiac arrest during hospitalization, and to observe whether differences exist in terms of patients' profiles, surveillance measurements and outcomes. Method A descriptive, observational, retrospective, cross-sectional design, randomly including data from electronic documentation of patients who experienced a cardiac arrest during hospitalization in any of the 107 adult wards of eight acute care facilities. Descriptive statistics were used for data analysis. Two-tailed p-values are reported. Results Almost 60% of the analyzed patients' e-charts had surveillance nursing diagnoses charted in the electronic care plans. Significant differences were found for patients who had these diagnoses documented and those who had not in terms of frequency of vital signs measurements and final outcomes. Conclusion Surveillance nursing diagnoses may play a significant role in preventing acute deterioration of adult in-patients in the acute care setting.

Surveillance nursing diagnoses, ongoing assessment and outcomes on in-patients who suffered a cardiorespiratory arrest / Diagnósticos de enfermagem de vigilância, avaliação contínua e resultados em pacientes que sofreram uma parada cardiorrespiratória / Diagnósticos enfermeros de vigilancia, evaluación en curso y resultados en pacientes hospitalizados que sufrieron paro cardiorrespiratorio

ABSTRACT Objective The purposes of this study were to examine the frequency of surveillance-oriented nursing diagnoses and interventions documented in the electronic care plans of patients who experienced a cardiac arrest during hospitalization, and to observe whether differences exist in terms of patients' profiles, surveillance measurements and outcomes. Method A descriptive, observational, retrospective, cross-sectional design, randomly including data from electronic documentation of patients who experienced a cardiac arrest during hospitalization in any of the 107 adult wards of eight acute care facilities. Descriptive statistics were used for data analysis. Two-tailed p-values are reported. Results Almost 60% of the analyzed patients' e-charts had surveillance nursing diagnoses charted in the electronic care plans. Significant differences were found for patients who had these diagnoses documented and those who had not in terms of frequency of vital signs measurements and final outcomes. Conclusion Surveillance nursing diagnoses may play a significant role in preventing acute deterioration of adult in-patients in the acute care setting.

RESUMO Objetivo Determinar a frequência de registro eletrônico de diagnósticos e intervenções de vigilância no plano de cuidados para pacientes que sofreram uma parada cardíaca durante a admissão e avaliar se existem diferenças com base no perfil do paciente, medidas de monitoramento e resultados. Método Estudo descritivo, observacional, retrospectivo, transversal, que incluiu dados dos registros eletrônicos de pacientes internados em uma das 107 unidades de oito hospitais de cuidados agudos. Para análise dos dados foram utilizados estatísticos descritivos. Os valores de p foram relatados em dois ramos. Resultados Foram obtidos dados de 492 documentos de enfermagem de pacientes que sofreram uma parada cardíaca. Quase 60% dos prontuários eletrônicos incluídos na análise continham um ou mais diagnósticos de vigilância. Diferenças significativas foram encontradas entre os pacientes com e sem registro desses diagnósticos, no que se refere à frequência das medições dos sinais vitais e aos resultados finais. Conclusão Os diagnósticos de vigilância podem desempenhar um papel importante na prevenção de deterioração aguda em pacientes adultos hospitalizados.

RESUMEN Objetivo Los objetivos de este estudio fueron examinar la frecuencia de los diagnósticos enfermeros basados en la vigilancia y las intervenciones documentadas en los planes de asistencia mediante sistema informático de pacientes que pasaron por paro cardiaco durante estancia hospitalaria y observar si existen diferencias en términos de perfil de los pacientes, medidas de vigilancia y resultados. Método Descriptivo, observacional, retrospectivo, transversal, randomizado, incluyendo datos de documentación informática de pacientes que pasaron por paro cardiaco durante estancia hospitalaria en cualquiera de las 107 alas adultas de las ocho instalaciones de cuidados intensivos. Las estadísticas descriptivas fueron utilizadas para los análisis de datos. Valores P bilaterales fueron relatados. Resultados Casi el 60% del los pacientes analizados por la gráfica electrónica tuvieron diagnóticos enfermeros de vigilancia representados en los planes de cuidados informatizados. Fueron encontradas diferencias significativas en pacientes que tuvieron dichos diagnósticos documentados y los que no los tuvieron en términos de frecuencia de mediciones de señales vitales y resultados finales. Conclusión Los diagnósticos enfermeros de vigilancia pueden jugar un rol significativo en la prevención del deterioro agudo de pacientes adultos hospitalizados en las unidades de cuidados intensivos.

Spanish consensus on premature menopause.

INTRODUCTION: While we recognise that the term premature menopause is more accepted by most non-specialist health care providers and by the general population, 'primary ovarian insufficiency' (POI) is currently considered the most apposite term to explain the loss of ovarian function, because it better explains the variability of the clinical picture, does not specify definitive failure, and highlights the specific ovarian source. Its pathogenesis involves a congenital reduction in the number of primordial follicles, poor follicle recruitment, or accelerated follicular apoptosis. However, its cause is unknown in most cases. AIM: This guide analyses the factors associated with the diagnosis and treatment of POI and provides recommendations on the most appropriate diagnostic and therapeutic measures for women under 40 years of age who experience POI. METHODOLOGY: A panel of experts from various Spanish scientific societies related to POI (Spanish Menopause Society, Spanish Fertility Society, and Spanish Contraception Society) met to reach a consensus on these issues. RESULTS: Hormonal therapy (HT) is considered the treatment of choice to alleviate the symptoms of hypoestrogenism and to prevent long-term consequences. We suggest that HT should be continued until at least age 51, the average age at natural menopause. The best treatment to achieve pregnancy is oocyte/embryo donation. If a patient is to undergo treatment that will reduce her fertility, she should be informed of this issue and the available techniques to preserve ovarian function, mainly vitrification of oocytes.

Periprosthetic fractures around the knee-the best way of treatment.

BACKGROUND: A variety of methods has been described to stabilise periprosthetic fractures around total knee arthroplasty (TKA). Our report offers a review of the actual strategies in the reduction and fixation of these fractures. Surgical treatment should be based on the following four steps:Diagnostics: By taking the patients' history together with an X-ray of the knee and femur, the fracture is analysed. It is crucial to define whether any losening of the prosthesis had occurred. In selected cases, CT-scan may add important information on the stability of the implant.Classification and planning: For most fractures around the distal femur, the Rorabeck classification is used while fractures around the proximal tibia are best classified according to the Felix classification. Additionally the Orthopaedic Trauma Association (OTA) may be helpful in the planning process for reduction and fixation.Surgigal technique: In fractures around a stable implant (Rorabeck type I and II; Felix type A and C), it is favourable to use plates and retrograde nails (in Rorabeck I or II with an open box of a TKA). For reduction, three methods are available: (a) the open technique (with direct or indirect reduction); (b) the mini open technique (direct reduction of the fracture by cerclage or lag screw and percutaneous plate fixation in OTA type 32 or 33-A1) and (c) the minimally invasive technique (indirect reduction and percutaneous fixation in all other OTA types). Fractures with a loose prosthesis (Rorabeck III and Felix B) are best stabilised by hinged revision arthroplasty.Rehabilitation: It is of great importance for the aged patient to be mobilised out of bed early. In most of the cases, partial weight bearing has to be performed by the aid of frames during the first 6 weeks after surgery. In a well-fixed revision prosthesis with a cemented stem, early full weight bearing might be allowed. CONCLUSION: Standardised less invasive procedures to treat periprosthetic fractures present a valuable alternative to open techniques. The main advantages are lower rates of oft tissue complications and implant failures following less invasive techniques of long plate application. Polyaxial locking systems allow for stable plate fixation around intramedullary implants.

Subtrochanteric fractures: treatment with cerclage wire and long intramedullary nail.

Fracture malalignment and nonunion are not infrequent after treating subtrochanteric fractures with intramedullary nails. The use of a cerclage wire with a minimally invasive approach to aid and maintain reduction in certain subtrochanteric fracture patterns can be an effective surgical strategy to improve outcome. It allows the surgeon to obtain and maintain an anatomic reduction with more bone contact, which will aid in fracture consolidation. This has the added advantage of optimizing the greater trochanteric starting point. It minimizes malreductions of the proximal femoral fragment, and, we believe, that its rational use with a minimally invasive technique is a key factor in achieving good results.

Traumatic floating clavicle: a case report.

Most published reports of a floating clavicle consist of a dislocation of both ends of the clavicle and are associated with a high-energy injury. We report a 71 year old patient with a fracture of the medial end of the clavicle with anterior sternoclavicular dislocation and a nondisplaced fracture of the lateral end of the same clavicle distal to the insertion of coracoclavicular ligaments due to a low velocity fall.

Lateral subtalar dislocation associated with bimalleolar fracture: case report and literature review.

Subtalar dislocation is an uncommon injury that affects the talocalcaneal and talonavicular joints, with the tibiotalar and calcaneocuboid joints remaining intact. The 4 types of subtalar dislocation are medial, lateral, anterior, and posterior, although the latter 2 are rare. These injuries-especially lateral dislocation-occur as a result of high-energy trauma. Medial dislocation is the most common type, and lateral dislocation is associated with osteochondral fractures of the talus and calcaneus, as well as with open injuries; hence, its worse prognosis. We report the case of a 62-year-old woman diagnosed with lateral subtalar dislocation accompanied by an ipsilateral bimalleolar fracture after a fall downstairs. She underwent emergency reduction of the dislocation under sedation. Surgical treatment of the bimalleolar fracture was delayed 9 days to avoid cutaneous complications. This is the first report of a subtalar dislocation accompanied by a bimalleolar fracture.

Expression of the tyrosine kinase discoidin domain receptor 1 (DDR1) in human central nervous system myelin.

During development of the mouse brain, the protein kinase discoidin domain receptor 1 (DDR1) is present prenatally in neurons of the proliferative areas, and postnatally, DDR1 expression is no longer detected in neurons, but a spatial-temporal expression pattern in oligodendrocytes that overlaps with the dynamics of the myelination process is detected. Notably, oligodendrocytic DDR1 expression is upregulated in mice during experimentally induced remyelination. Recently, we demonstrated that DDR1 expression is high in human brain and that there is an association between the gene and schizophrenia in a case-control study. However, data regarding expression of DDR1 in the human brain are scarce. Here, we describe the expression pattern of DDR1 in the human adult cerebral cortex. Using several immunohistological techniques and in situ hybridization, we identified DDR1 in the following: a) myelin, b) capillary endothelial cells in the gray as well as white matter, and c) in the soma of some oligodendrocytes and astrocytes in the white matter. The most important overall finding in this study was that DDR1 is present in myelin and is expressed by oligodendrocyte cells. We detected the presence of DDR1 mRNA and protein in myelin and observed that DDR1 co-localized with the classical myelin basic protein (MBP). Moreover, we found a strong positive correlation between expression levels of DDR1 and two myelin-associated genes, myelin-associated glycoprotein (MAG) and oligodendrocyte transcription factor 2 (OLIG2). These observations suggest that DDR1 could be an important constituent of myelin. Because defects in myelination are linked to several mental disorders such as schizophrenia, the function of DDR1 in the process of myelination warrants further investigation.

Discoidin domain receptor 1, a tyrosine kinase receptor, is upregulated in an experimental model of remyelination and during oligodendrocyte differentiation in vitro.

The discoidin domain receptor (DDR1) is highly expressed in oligodendrocytes during the neurodevelopmental myelination process and is genetically associated to schizophrenia. In this study, we aimed to further assess the involvement of DDR1 in both remyelination and oligodendrocyte differentiation. In the mouse model of demyelination-remyelination induced by oral administration of cuprizone, in situ hybridization showed an upregulation of the DDR1 gene in three different white matter areas (corpus callosum, dorsal fornix, and external capsule) during the remyelination period. Moreover, real time reverse transcriptase polymerase chain reaction showed that the increase in DDR1 messenger RNA (mRNA) was strongly correlated with the number of DDR1-positive cells in the corpus callosum (Spearman coefficient = 0.987, P = 0.013). Cells positive for DDR1 mRNA were also positive for oligodendrocyte markers (OLIG2, carnosine, and APC) but not for markers of oligodendrocyte precursors (NG2), myelin markers (CNPase), microglia (CD11b), or reactive glia (GFAP). Differentiation of a human oligodendroglial cell line, HOG16, was associated with an increase in mRNA expression of DDR1 and several myelin proteins (MBP and MOBP) but not other proteins (APC and CNPase). Here, we demonstrate that DDR1 is upregulated in vitro and in vivo when oligodendrocyte myelinating machinery is activated. Further studies are needed to identify the specific molecular pathway.