Neurogenic bladder as a lurking complication in Moebius syndrome.

Moebius syndrome (MBS) is a congenital disorder characterized by facial and abducens palsy, sometimes accompanied with other cranial nerve palsies and comorbid conditions. Anatomical anomalies of the brainstem are assumed to be major etiologies of MBS. Its phenotypic presentation can be variable. We report a female patient with MBS who presented with neurogenic bladder (NB). She was born via normal vaginal delivery. At birth, she showed bilateral abducens palsy and right facial palsy. We diagnosed MBS by cranial computed tomography scan and magnetic resonance imaging. She had recurrent urinary tract infection. Hydronephrosis was noted on ultrasonography and bilateral vesicoureteral reflux (grade 5) on voiding cystourethrography. Urodynamic investigation showed detrusor overactivity and detrusor-sphincter dyssynergia, which follow the pattern of NB resulting from infrapontine-suprasacral lesions. Patients with MBS have lower brainstem dysfunction, and accordingly we should be aware of NB.

A New Neurorehabilitative Postsurgery Intervention for Facial Palsy Based on Smile Observation and Hand-Mouth Motor Synergies.

Objective: To perform a preliminary test of a new rehabilitation treatment (FIT-SAT), based on mirror mechanisms, for gracile muscles after smile surgery. Method: A pre- and postsurgery longitudinal design was adopted to study the efficacy of FIT-SAT. Four patients with bilateral facial nerve paralysis (Moebius syndrome) were included. They underwent two surgeries with free muscle transfers, one year apart from each other. The side of the face first operated on was rehabilitated with the traditional treatment, while the second side was rehabilitated with FIT-SAT. The FIT-SAT treatment includes video clips of an actor performing a unilateral or a bilateral smile to be imitated (FIT condition). In addition to this, while smiling, the participants close their hand in order to exploit the overlapped cortical motor representation of the hand and the mouth, which may facilitate the synergistic activity of the two effectors during the early phases of recruitment of the transplanted muscles (SAT). The treatment was also aimed at avoiding undesired movements such as teeth grinding. Discussion. Results support FIT-SAT as a viable alternative for smile rehabilitation after free muscle transfer. We propose that the treatment potentiates the effect of smile observation by activating the same neural structures responsible for the execution of the smile and therefore by facilitating its production. Closing of the hand induces cortical recruitment of hand motor neurons, recruiting the transplanted muscles, and reducing the risk of associating other unwanted movements such as teeth clenching to the smile movements.

Differentiating Moebius syndrome and other congenital facial weakness disorders with electrodiagnostic studies.

INTRODUCTION: Congenital facial weakness (CFW) can result from facial nerve paresis with or without other cranial nerve and systemic involvement, or generalized neuropathic and myopathic disorders. Moebius syndrome is one type of CFW. In this study we explored the utility of electrodiagnostic studies (EDx) in the evaluation of individuals with CFW. METHODS: Forty-three subjects enrolled prospectively into a dedicated clinical protocol and had EDx evaluations, including blink reflex and facial and peripheral nerve conduction studies, with optional needle electromyography. RESULTS: MBS and hereditary congenital facial paresis (HCFP) subjects had low-amplitude cranial nerve 7 responses without other neuropathic or myopathic findings. Carriers of specific pathogenic variants in TUBB3 had, in addition, a generalized sensorimotor axonal polyneuropathy with demyelinating features. Myopathic findings were detected in individuals with Carey-Fineman-Ziter syndrome, myotonic dystrophy, other undefined myopathies, or CFW with arthrogryposis, ophthalmoplegia, and other system involvement. DISCUSSION: EDx in CFW subjects can assist in characterizing the underlying pathogenesis, as well as guide diagnosis and genetic counseling.

Efficient recognition of facial expressions does not require motor simulation.

What mechanisms underlie facial expression recognition? A popular hypothesis holds that efficient facial expression recognition cannot be achieved by visual analysis alone but additionally requires a mechanism of motor simulation - an unconscious, covert imitation of the observed facial postures and movements. Here, we first discuss why this hypothesis does not necessarily follow from extant empirical evidence. Next, we report experimental evidence against the central premise of this view: we demonstrate that individuals can achieve normotypical efficient facial expression recognition despite a congenital absence of relevant facial motor representations and, therefore, unaided by motor simulation. This underscores the need to reconsider the role of motor simulation in facial expression recognition.

Electromyographic evaluation of the facial and motor donor nerves before facial reanimation surgery in Moebius syndrome.

BACKGROUND: Moebius syndrome is a clinical entity characterized by bilateral facial and abducens nerve palsies; other cranial nerver might be affected as well. So far, no studies have reported the electromyographic responses of the facial musculature in this group of patients. OBJECTIVE: The objective of our study is to describe the electromyographic responses of the facial muscle and the main donor nerves for facial reanimation in patients with Moebius syndrome. METHOD: We analyzed electromyographies from the facial, hypoglossal, masseterine (trigeminal) and accessory nerves from patients with Moebius syndrome treated between 2010 and 2016. Results are presented as percentages and central tendency measures. RESULTS: 24 patients were included, mean age 11.79 ± 9.39 years. The facial nerve showed complete unilateral recruitment in 4 patients, partial bilaterally in 11, 7 showed no activity bilaterally and two had unilateral inactivity. The masseterine was normal in 14 patients, had partial recruitment bilaterally in 4 and unilaterally in 4 cases. The accessory nerve was normal in 20 patients, showed partial recruitment bilaterally in 3 and unilaterally in 1 patients. The hypoglossal was normal in 22 patients, and altered in 2 cases. CONCLUSION: Patients with Moebius syndrome show several degrees of alteration in electromyographic evaluation of the facial nerve. Electromyography is a useful tool in evaluating potential motor donor nerves for facial reanimation surgery.

ANTECEDENTES: El síndrome de Moebius es una entidad clínica caracterizada por parálisis bilateral congénita del nervio facial y el abducens. Adicionalmente se pueden encontrar afectados otros pares craneales. Actualmente no existen estudios que reporten la respuesta electromiográfica de la musculatura facial en esta población. OBJETIVO: Describir la respuesta electromiográfica de la musculatura facial y de los principales nervios donadores para reconstrucción facial dinámica en pacientes con síndrome de Moebius. MÉTODO: Se analizaron electromiografías de los nervios facial, hipogloso, maseterino (trigémino) y accesorio en pacientes con síndrome de Moebius atendidos entre 2010 y 2016. Los resultados se presentan en porcentajes y medidas de tendencia central y de dispersión. RESULTADOS: Se incluyeron 24 pacientes, con una edad promedio de 11.79 ± 9.39 años. El nervio facial presentó reclutamiento unilateral completo en 4 pacientes, parcial bilateral en 11 pacientes, en 7 pacientes ausencia de reclutamiento bilateral e inactividad unilateral en 2 pacientes. El maseterino tuvo reclutamiento completo en 14 pacientes, parcial bilateral en 4 pacientes y parcial unilateral en 4 pacientes. El nervio accesorio mostró reclutamiento completo en 20 pacientes, parcial bilateral en 3 pacientes y parcial unilateral en 1 paciente. El hipogloso mostró actividad normal en 22 pacientes, parcial bilateral en 1 paciente y parcial unilateral en 1 paciente. CONCLUSIÓN: Los pacientes con síndrome de Moebius presentan alteraciones en los registros electromiográficos del nervio facial. La electromiografía permite identificar los nervios donadores para realizar la reconstrucción dinámica.

Orofacial motor dysfunction in Moebius syndrome.

AIM: To review orofacial disabilities and their consequences in children with Moebius syndrome (MBS). METHOD: We retrospectively analysed the records of 32 patients (21 males, 11 females) with non-progressive bilateral facial and abducens palsies who had been examined before 6 months of age. RESULTS: All facial muscles were severely involved in 17 patients; in the 15 others, partial movements were found in the lower face. Most patients (n=24) were unable to smile. Patients frequently presented with congenital trismus (n=20) and drooling (n=18). Additional palsies involved cranial nerves IX and X (n=18) and XII (n=25). Sucking was absent or weak in 30 patients; swallowing was impaired in 25. During the first month of life, feeding disorders were graded as severe/moderate in 25. Respiratory complications occurred in 17. Severe feeding disorders were associated with congenital trismus (p=0.01) and with cranial nerve IX and X palsy (p=0.01). Growth failure between 1 and 6 months of age, followed by catch-up growth between 6 and 12 months, was observed in 20 patients. Between 2 and 5 years of age, 25 out of 32 patients attained normal oral diet and 28 out of 29 showed normal growth. INTERPRETATION: Children with MBS frequently require adjusted therapeutic options to prevent failure to thrive. Congenital trismus, cranial nerve IX and X palsy, and laryngeal-tracheal dysfunctions are predictors of severe feeding disorders. WHAT THIS PAPER ADDS: Moebius syndrome frequently induces reduced oral intake and early failure to thrive. Normal oral diet and growth parameters are attained at 2 to 5 years of age. Congenital trismus, pharyngeal palsy, and laryngeal disorders predict dysphagia.

Difficult Airway Identification and Management in Patients With Moebius Syndrome.

BACKGROUND: Airway management in patients with Moebius syndrome can be difficult due to the presence of orofacial malformations. This paper aims to present our institution's experience in the evaluation and management of the upper airway in patients with Moebius syndrome METHODOLOGY:: The authors performed a retrospective study including every patient with Moebius syndrome submitted to surgery between 2012 and 2017. Difficult airway was defined as one requiring more than 2 attempts to achieve endotracheal tube placement, a Mallampati score equal or above III, a Cormack score equal or above III, or need of a fiberscope during intubation. RESULTS: Fifty-one patients were included, (39.3% males) requiring 172 procedures. Each patient required an average of 3.37 ±â€Š1.94 anesthetic events. Average Body Mass Index (BMI) was 20.07 ±â€Š6.06, 45.1% were overweight or obese. Four patients (7%) were considered as having a potentially difficult airway. Endotracheal intubation was achieved in all patients; 38 patients were intubated in a single attempt, while the rest were successfully intubated on a second try. Fiberscope was not necessary. Univariate analysis showed that overweight/obese patients were more likely to be considered as having a difficult airway (P = 0.03). CONCLUSION: Intubation can be difficult in patients with Moebius syndrome, but failure is rare. Overweight or obese patients are at risk of presenting a difficult airway. An extensive preoperative evaluation and adequate communication between the members of the multidisciplinary team in charge of these patients is paramount.

Children with facial paralysis due to Moebius syndrome exhibit reduced autonomic modulation during emotion processing.

BACKGROUND: Facial mimicry is crucial in the recognition of others' emotional state. Thus, the observation of others' facial expressions activates the same neural representation of that affective state in the observer, along with related autonomic and somatic responses. What happens, therefore, when someone cannot mimic others' facial expressions? METHODS: We investigated whether psychophysiological emotional responses to others' facial expressions were impaired in 13 children (9 years) with Moebius syndrome (MBS), an extremely rare neurological disorder (1/250,000 live births) characterized by congenital facial paralysis. We inspected autonomic responses and vagal regulation through facial cutaneous thermal variations and by the computation of respiratory sinus arrhythmia (RSA). These parameters provide measures of emotional arousal and show the autonomic adaptation to others' social cues. Physiological responses in children with MBS were recorded during dynamic facial expression observation and were compared to those of a control group (16 non-affected children, 9 years). RESULTS: There were significant group effects on thermal patterns and RSA, with lower values in children with MBS. We also observed a mild deficit in emotion recognition in these patients. CONCLUSION: Results support "embodied" theory, whereby the congenital inability to produce facial expressions induces alterations in the processing of facial expression of emotions. Such alterations may constitute a risk for emotion dysregulation.

Autonomic Responses to Emotional Stimuli in Children Affected by Facial Palsy: The Case of Moebius Syndrome.

According to embodied simulation theories, others' emotions are recognized by the unconscious mimicking of observed facial expressions, which requires the implicit activation of the motor programs that produce a specific expression. Motor responses performed during the expression of a given emotion are hypothesized to be directly linked to autonomic responses associated with that emotional behavior. We tested this hypothesis in 9 children (M age = 5.66) affected by Moebius syndrome (MBS) and 15 control children (M age = 6.6). MBS is a neurological congenital disorder characterized by underdevelopment of the VI and VII cranial nerves, which results in paralysis of the face. Moebius patients' inability to produce facial expressions impairs their capacity to communicate emotions through the face. We therefore assessed Moebius children's autonomic response to emotional stimuli (video cartoons) by means of functional infrared thermal (fIRT) imaging. Patients showed weaker temperature changes compared to controls, suggesting impaired autonomic activity. They also showed difficulties in recognizing facial emotions from static illustrations. These findings reveal that the impairment of facial movement attenuates the intensity of emotional experience, probably through the diminished activation of autonomic responses associated with emotional stimuli. The current study is the first to investigate emotional responses in MBS children, providing important insights into the role of facial expressions in emotional processing during early development.

Congenital facial palsy and emotion processing: The case of Moebius syndrome.

According to the Darwinian perspective, facial expressions of emotions evolved to quickly communicate emotional states and would serve adaptive functions that promote social interactions. Embodied cognition theories suggest that we understand others' emotions by reproducing the perceived expression in our own facial musculature (facial mimicry) and the mere observation of a facial expression can evoke the corresponding emotion in the perceivers. Consequently, the inability to form facial expressions would affect the experience of emotional understanding. In this review, we aimed at providing account on the link between the lack of emotion production and the mechanisms of emotion processing. We address this issue by taking into account Moebius syndrome, a rare neurological disorder that primarily affects the muscles controlling facial expressions. Individuals with Moebius syndrome are born with facial paralysis and inability to form facial expressions. This makes them the ideal population to study whether facial mimicry is necessary for emotion understanding. Here, we discuss behavioral ambiguous/mixed results on emotion recognition deficits in Moebius syndrome suggesting the need to investigate further aspects of emotional processing such as the physiological responses associated with the emotional experience during developmental age.

Will the real Moebius syndrome please stand up? A systematic review of the literature and statistical cluster analysis of clinical features.

Moebius syndrome is a highly variable syndrome with abducens and facial nerve palsy as core features. Strict diagnostic criteria do not exist and the inconsistency of the associated features makes determination difficult. To determine what features are associated with Moebius syndrome we performed a systematic literature review resulting in a composite case series of 449 individuals labeled with Moebius syndrome. We applied minimum criteria (facial and abducens palsy) to determine the prevalence of associated clinical features in this series. Additionally, we performed statistical cluster analysis to determine which features tended to occur together. Our study comprises the largest series of patients with Moebius syndrome and the first to apply statistical methodology to elucidate clinical relationships. We present evidence for two groups within the Moebius diagnosis. Type 1: exhibiting micrognathia, limb anomalies and feeding/swallowing difficulty that tend to occur together. Type 2: phenotypically diverse but more associated with radiologically detectable neurologic abnormalities and developmental delay.

Möbius syndrome associated with obesity and precocious puberty.

Möbius syndrome is a neurological disorder involving underdevelopment of the sixth and seventh cranial nerves. Multiple associations have been described including dysfunction of other cranial nerves, limb abnormalities and hypogonadotrophic hypogonadism causing delayed puberty. We present the second reported case of Möbius syndrome associated with obesity and with precocious puberty. These features may be secondary to dysregulation of the hypothalamic-pituitary axis. We highlight the need to consider extraocular symptoms in these patients and for close liaison with physicians in their management.

Knockout of myomaker results in defective myoblast fusion, reduced muscle growth and increased adipocyte infiltration in zebrafish skeletal muscle.

The fusion of myoblasts into multinucleated muscle fibers is vital to skeletal muscle development, maintenance and regeneration. Genetic mutations in the Myomaker (mymk) gene cause Carey-Fineman-Ziter syndrome (CFZS) in human populations. To study the regulation of mymk gene expression and function, we generated three mymk mutant alleles in zebrafish using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology and analyzed the effects of mymk knockout on muscle development and growth. Our studies demonstrated that knockout of mymk resulted in defective myoblast fusion in zebrafish embryos and increased mortality at larval stage around 35-45 days post-fertilization. The viable homozygous mutants were smaller in size and weighed approximately one-third the weight of the wild type (WT) sibling at 3 months old. The homozygous mutants showed craniofacial deformities, resembling the facial defect observed in human populations with CFZS. Histological analysis revealed that skeletal muscles of mymk mutants contained mainly small-size fibers and substantial intramuscular adipocyte infiltration. Single fiber analysis revealed that myofibers in mymk mutant were predominantly single-nucleated fibers. However, myofibers with multiple myonuclei were observed, although the number of nuclei per fiber was much less compared with that in WT fibers. Overexpression of sonic Hedgehog inhibited mymk expression in zebrafish embryos and blocked myoblast fusion. Collectively, these studies demonstrated that mymk is essential for myoblast fusion during muscle development and growth.

[Electromyographic assessment of the temporalis muscle prior to a lengthening myoplasty in patients with Moebius syndrome]. / Étude électromyographique du muscle temporalis avant une myoplastie d'allongement dans le syndrome de Moebius.

BACKGROUND/OBJECTIVES: Temporalis muscle lengthening myoplasty improves tightening of the lips and rehabilitates smile for patients with congenital facial palsies. Because Moebius syndrome is heterogeneous, a careful evaluation is mandatory before deciding to perform myoplasty. This series shows the role of electromyography for investigating temporalis muscle and trigeminal nerve motor functions. METHODS: We conducted a retrospective study of 18 patients with no upward movements of the labial commissure and absent or unsightly smile. Electromyography was used to study the temporalis muscle bilaterally. Analysis focused on the recruitment pattern of voluntary contraction and electrical silence or activity at rest. Traces were classified as normal, neurogenic, or low-amplitude. Functional outcomes of myoplasty were evaluated by measuring the upward movement of the commissure (mm), and qualified as high (≥10), medium (>5), or little (≤5). RESULTS: Surgery was cancelled for 5 patients with abnormal electromyographic signs, neurogenic (2) or low-amplitude (3). Myoplasty was performed in 7 patients (age: 8-17 years), unilaterally (3) or bilaterally (4). Preoperative electromyogram was normal (3), or showed moderate neurogenic (2) or low-amplitude (2) changes. Follow-up period after surgery was from 2 to 12 years; functional outcomes were high (5), medium (1), or little (1). CONCLUSION: Electromyographic study of the temporalis can detect muscle denervation or atrophy, or dyspraxia, and guide decision to encourage or discourage performing myoplasty, or enhance rehabilitation programme and make the patient aware of possibly modest outcome.

Clinical characteristics and outcomes of Möbius syndrome in a children's hospital.

BACKGROUND: Möbius syndrome is a congenital disorder with facial and abducens palsy. Although a few case series studies have examined comorbid conditions in Möbius syndrome, follow-up and outcome data are sparse. OBJECTIVES: To examine the clinical characteristics and outcomes of Möbius syndrome. METHODS: Clinical data were reviewed for 10 patients. Neonatal history, neurological examination, comorbid anomalies, medical home care, outcomes, and neuroimaging were summarized. RESULTS: The patients' mean age was 7.3 ± 6.2 years. On neurological examination, absent blink reflex, jaw ankylosis, absent gag reflex, and tongue atrophy were frequently observed. Poland anomaly and clubfoot were present in three and six patients, respectively. Specific therapies required for patients included medical home care (six patients), suction apparatus (six), tube feeding (five), gastrostomy (two), tracheostomy (three), oxygen therapy (three), and home ventilator (two). Punctate calcification in the brainstem was observed in four patients. Pontine and medulla hypoplasia were detected on the basis of anteroposterior diameter in four and seven patients, respectively. Two patients had congenital hydrocephalus with aqueductal stenosis. Global developmental delay occurred in five patients. Three patients died. CONCLUSION: The rate of both the use of home medical devices and death was high in our patients. Möbius syndrome is extremely diverse, not only in clinical manifestation, but also outcome. Early multidisciplinary intervention is important to ensure an optimal outcome. Aqueductal stenosis is an occasional comorbid anomaly resulting from midbrain abnormality.

Teratogen exposure and congenital ocular abnormalities in Brazilian patients with Möbius sequence / Exposição à teratógenos e anormalidades oculares congênitas em pacientes brasileiros portadores da sequência de Möbius

Purpose: To assess the sociodemographic profiles, teratogen exposures, and ocular congenital abnormalities in Brazilian patients with Möbius sequence. Method: Forty-four patients were recruited from the Brazilian Möbius Sequence Society. This cross-section comprised 41 patients (age, mean ± standard deviation, 9.0 ± 5.5 years) who fulfilled the inclusion criteria. The parent or caregiver answered a questionnaire regarding sociodemographic data and pregnancy history. Patients underwent ophthalmological assessments. They were subdivided into groups according to misoprostol exposure during pregnancy, and the two groups were compared. Results: Mothers/caregivers reported unplanned pregnancies in 36 (88%) cases. Of these, 19 (53%) used misoprostol during their first trimesters. A stable marital status tended to be more frequent in the unexposed group (P=0.051). Incomplete elementary school education was reported by two (11%) mothers in the exposed group and by three (14%) mothers in the unexposed group (P=0.538). The mothers' gestational exposures to cocaine, marijuana, alcohol, and cigarettes were similar in both groups (P=0.297, P=0.297, P=0.428, and P=0.444, respectively). One (5%) case of Rubella infection during pregnancy was found in the unexposed group. The main malformations in the exposed and unexposed groups were the following: strabismus (72% and 77%, respectively), lack of emotional tearing (47% and 36%, respectively), and lagophthalmos (32% and 41%, respectively). Conclusion: Stable marital statuses tended to be more frequent among mothers that did not take misoprostol during pregnancy. Exposures to other teratogens and the main ocular abnormalities were similar in both groups. .

Objetivo: Descrever o perfil sóciodemográfico, exposição à teratógenos e anormalidades oculares congênitas em pacientes brasileiros portadores da sequência de Möbius Método: Quarenta e quatro pacientes recrutados da Sociedade Brasileira de Sequência de Möbius foram examinados. Este estudo transversal incluiu 41 pacientes que preencheram os critérios de inclusão do estudo (média das idades: 9,0 ± 5,5 anos). Mãe/responsável dos pacientes responderam a um questionário sobre perfil sóciodemográfico e história gestacional. Foi realizado exame oftalmológico de todos os pacientes. Eles foram agrupados em dois grupos de acordo com a exposição ao misoprostol durante a gestação e seus dados foram comparados. Resultados: Mães/responsáveis referiram gravidez indesejada em 36 (88%) dos casos. Destas, 19 (53%) fizeram uso de misoprostol no primeiro trimestre de gestação. Houve uma tendência do grupo de mães não expostas ao misoprostol de terem um estado civil estável (P=0,051). Duas (11%) mães do grupo de expostas ao misoprostol relataram primeiro grau incompleto e três (14%) do grupo de não expostas (P=0,538). A exposição das mães à cocaína, maconha, álcool e cigarro foi similar em ambos os grupos (P=0,297, P=0,297, P=0,428, P=0,444, respectivamente). Houve um caso (5%) de Rubéola no grupo de mães não expostas. As principais malformações associadas nos pacientes expostos e não expostos foram, respectivamente: estrabismo (72% e 77%), e diminuição da lágrima emocional (47% e 36%) e lagoftalmia (32% and 41%). Conclusão: Estado civil estável foi mais frequente em mães que não fizeram uso de misoprostol durante a gestação. Exposição à outros ...

A novel de novo KIF21A mutation in a patient with congenital fibrosis of the extraocular muscles and Möbius syndrome.

PURPOSE: To describe the phenotypic characteristics and clinical course of a sporadic case of congenital fibrosis of the extraocular muscles (CFEOM) and Möbius syndrome with a de novo mutation in the KIF21A gene encoding a kinesin motor protein. METHODS: An individual with the rare combination of CFEOM and Möbius syndrome underwent comprehensive ophthalmologic and neurological evaluations. Magnetic resonance imaging (MRI) including diffusion tensor imaging (DTI) tractigraphy at 3T field strength was used to evaluate orbital, encephalic, and intracranial nerve integrity. The proband and her healthy parents underwent screening for mutations in the KIF21A, PHOX2A, and TUBB3 genes. RESULTS: The patient exhibited congenital, nonprogressive, bilateral external ophthalmoplegia, bilateral ptosis, bilateral facial palsy, and developmental delay. Her inability to blink resulted in severe exposure keratopathy and subsequent corneal perforation requiring a penetrating keratoplasty. MRI revealed an unremarkable configuration of the axial central nervous system and preservation of the intracranial portion of cranial nerves I, II, III, V, VI, VII, and VIII (cranial nerve IV is not normally visualized by MRI). A novel and de novo heterozygous KIF21A mutation (c.1056C>G, p.Asp352Glu) in a highly conserved region of the gene was present in the proband. CONCLUSIONS: The reported KIF21A D352E mutation and associated phenotype further expand the clinical and mutational spectrum of CFEOM and Möbius syndrome.