Histiocitoma fibroso maligno: estudio hisotpatologico e inmunohistoquímico / Malignant Fibrous Histiocytoma: Histopathological and Immunohistochemical Study

El histiocitoma fibroso maligno (MFH) es el tumor de tejido blando más común en adultos. Generalmente se considera que surge de las células mesenquimales primitivas que muestran diferenciación histiocítica y fibroblástica parcial. Las observaciones inmunohistoquímicas sugieren que la expresión de marcadores del músculo liso en el llamado MFH es el resultado de la diferenciación miofibroblástica. El presente estudio tiene como objetivo correlacionarse entre el subtipo histipatológico y los parámetros clínicos, calificar los casos de MFH dependiendo de los criterios histopatológicos para la clasificación, y examinar los casos inmunohistoquímicamente para la diferenciación miofibroblástica utilizando marcadores musculares lisos en casos de MFH como una ayuda para un diagnóstico preciso para un diagnóstico preciso. . Este estudio incluye 26 muestras de tejidos blandos diagnosticados como MFH recolectados de laboratorios histopatológicos privados y gubernamentales en Basrah durante el período de enero de 2000 a octubre de 2005. 4 casos adicionales (un leiomioma, dos fibromas y un fibrosarcoma se tomaron como control positivo y negativo. Los casos de MFH (77%) estaban en el grupo de edad de 45 a 60 años. La edad media fue de 53.5 años con una relación hombre / mujer de 1.3: 1. Diecinueve casos (73%) se ubicaron en las extremidades principalmente en las extremidades inferiores. Diecisiete años. Los casos (65.4%) fueron primarios. Veintidós (84.8%) eran de subtipo pleomórfico, dos eran mixoides y 2 eran inflamatorios. Todos los casos recurrentes se consideraban como el Grado III, de los diecisiete casos principales eran de grado III, por lo que veinte y veinte Tres casos (88.5%) fueron de grado III, los 3 casos restantes fueron de grado II. No se registró tumor de grado I. La mayoría de los casos de subtipo pleomórficos (95.5%) fueron de grado III. Ambos casos de subtipo mixoide fueron de grado Ii. Desmin expr Se encontró la en 3 casos (11.5%), ninguno para la actina del músculo liso o la proteína S-100. No hubo correlación entre la expresión de desmin y el sitio tumoral, subtipo o grado, así como, con la edad y el sexo de los pacientes. Se encontró una fuerte asociación entre la expresión de desmin y los tumores recurrentes del 33,3%

Malignant fibrous histiocytoma (MFH) is the most common soft tissue tumor in adult. It is generally regarded as arising from primitive mesenchymal cells that show partial histiocytic and fibroblastic differentiation. Immunohistochemical observations suggest that the expression of smooth muscle markers in the so called MFH is a result of myofibroblastic differentiation. The present study is aimed to correlate between histipathological subtype and clinical parameters, to grade the MFH cases depending on the histopathological criteria for grading, and to examine the cases immunohistochemically for myofibroblastic differentiation using smooth muscle markers in cases of MFH as an aid for accurate diagnosis. This study including 26 soft tissue specimens diagnosed as MFH collected from private and governmental histopathological laboratories in Basrah during the period from January 2000 to October 2005. Additional 4 cases (one leiomyoma, two fibromas and one fibrosarcoma were taken as control positive and negative. Twenty cases of MFH (77%) were in the age group 45-60 years. The mean age was 53.5 year with male to female ratio of 1.3: 1. Nineteen cases (73%) were located in the extremities mainly the lower limbs. Seventeen cases (65.4%) were primary. Twenty two (84.8%) were of pleomorphic subtype, two were myxoid and 2 were inflammatory. All the recurrent cases were regarded as grade III, from the seventeen primary cases fourteen were of grade III, so twenty three cases (88.5%) were of grade III, the remaining 3 cases were of grade II. No grade I tumor was recorded. The majority of pleomorphic subtype cases (95.5%) were of grade III. Both cases of myxoid subtype were of grade II. Desmin expression was found in only 3 cases (11.5%), none for smooth muscle actin or S-100 protein. There was no correlation between desmin expression and tumor site, subtype or grade, as well as, with age and sex of the patients. A strong association between desmin expression and recurrent tumors 33.3% was found.

Leiomiomatosis vulvovaginal: reporte de un caso y revisión bibliográfica / Vulvo-Vaginal Leiomyomatosis: Case Report and Review of the Literature

Resumen ANTECEDENTES: Los leiomiomas son los tumores pélvicos más frecuentes en la mujer; sin embargo, su localización vaginal es excepcional. Suelen ser asintomáticos y encontrarse como un hallazgo clínico. En los últimos 20 años solo se han reportado 85 casos, y solo dos han sido recurrentes. OBJETIVO: Reportar un caso de miomatosis vaginal recurrente en una paciente histerectomizada y revisar la bibliografía al respecto. CASO CLÍNICO: Paciente de 58 años, histerectomizada, con una tumoración vaginal. El reporte histopatológico informó una proliferación fusocelular, debidamente delimitada, dispuesta en haces entrecruzados. Los núcleos eran alargados, monomorfos y de extremos romos. El estroma era escaso y colagénico. No se observaron atipias citonucleares ni necrosis. El estudio inmunohistoquímico de la lesión con actina de anticuerpos antimúsculo liso y desmina se reportó positivo. Se diagnosticó miomatosis vulvovaginal recurrente. Se trató mediante resección quirúrgica. CONCLUSIÓN: Los leiomiomas vulvovaginales son extremadamente raros y la bibliografía al respecto es poca; su recurrencia es verdaderamente excepcional. De ahí la importancia de la publicación de estos casos, que aporta información que pueden tomar en cuenta otros clínicos al momento del diagnóstico.

Abstract BACKGROUND: Leiomyomas are the most frequent pelvic tumors in women; however, their vaginal location is unusual. They are usually asymptomatic and present as a clinical finding. In the last 20 years only 85 cases have been reported, and only two have been recurrent. OBJECTIVE: To report a case of recurrent vaginal myomatosis in a hysterectomized patient and review the literature. CLINICAL CASE: A 58-year-old hysterectomized patient with a vaginal tumor. The histopathologic report reported a fusocellular proliferation, properly delimited, arranged in crisscross bundles. The nuclei were elongated, monomorphous and blunt ended. The stroma was sparse and collagenous. No cytonuclear atypia or necrosis were observed. Immunohistochemical study of the lesion with anti-smooth muscle antibody actin and desmin was reported positive. Recurrent vulvovaginal myomatosis was diagnosed. It was treated by surgical resection. CONCLUSION: Vulvovaginal leiomyomas are extremely rare, and the literature is sparse; their recurrence is truly exceptional. Hence the importance of publishing these cases, providing information to be considered by other clinicians at the time of diagnosis.

Clinicopathological study of cystic and atypical uterine leiomyoma: a rare entity / Estudo clinicopatológico de leiomioma uterino atípico e cístico: uma entidade rara

ABSTRACT A 43-years-old Brazilian woman, Caucasian, premenopausal, was attended with a history of lower abdominal pain, distension, and bleeding. Pelvic and transvaginal ultrasound revealed an enlarged uterus with a large, well-defined, uniformly hyperechoic lesion. The patient underwent total hysterectomy and the specimen was sent for anatomopathological evaluation. The histopathological analyses revealed a leiomyoma with extensive cystic degeneration and atypical characteristics, the immunohistochemical study confirmed the benignity of the case. The finding of atypical leiomyoma with cystic degeneration is rare and should be carefully evaluated to exclude malignant diseases.

RESUMEN Mujer brasileña de 43 años, caucásica, premenopáusica, fue atendida con antecedentes de dolor abdominal bajo, distensión y menorragias. La ecografía pélvica y transvaginal reveló un útero agrandado con una lesión grande, bien definida y uniformemente hiperecoica. La paciente fue sometida a histerectomía total y la pieza fue enviada para evaluación anatomo-patológica. Los análisis histopatológicos revelaron un leiomioma con degeneración quística extensa de características atípicas y la inmunohistoquímica confirmó la benignidad del caso. El hallazgo de un leiomioma atípico con degeneración quística es raro y debe evaluarse cuidadosamente para descartar enfermedades malignas.

RESUMO Mulher brasileira, 43 anos de idade, caucasiana, na pré-menopausa, foi atendida devido a história de dor em abdômen inferior, distensão e sangramento. A ultrassonografia pélvica e transvaginal revelou útero aumentado com grande lesão hiperecoica, bem definida e uniforme. A paciente foi submetida à histerectomia total, e a amostra foi enviada para avaliação anatomopatológica. A análise histopatológica revelou quadro de leiomioma com degeneração cística extensa e características atípicas; o estudo imuno-histoquímico confirmou a benignidade do caso. O achado de leiomioma atípico com degeneração cística é raro e deve ser cuidadosamente avaliado para excluir doenças malignas.

Effects of ultrasound and stretching on skeletal muscle contusion in rats: immunohistochemistry analysis / Efectos de ultrasonido y estiramiento en la contusión muscular esqueletal en ratas: análisis inmunohistoquímico

SUMMARY: The aim of this study was to evaluate the effects of stretching and therapeutic ultrasound (TUS) on desmin and laminin contents of rat muscle after contusion. Male Wistar rats (n = 35, 8-9 weeks of age, 271 ± 14g body weight) were divided into five groups: Control group (CG) (n= 03); Injured group (IG) (n= 8); Injured + ultrasound group (IUSG) (n= 8); Injured+stretching group (ISG) (n= 8); Injured +ultrasound + stretching group (IUSSG) (n= 8). The application of ultrasound started 72 hours after the contusion, using the 50 % pulsed mode, 0.5 W/cm2, 5 min, once a day, for five consecutive days. Passive manual stretching was started on the tenth day after injury, with four repetitions of 30 s each and 30 s rest between repetitions, once a day, five times per week, for a total of ten applications. After 22 days, the rats were euthanazied and the gastrocnemius of both limbs removed for desmin and laminin immunohistochemistry morphometric measurement. Analysis was conducted using ANOVA one way post-hoc Tukey to parametric data and Kruskall-Wallis for non-parametric data. The IUSSG animals showed a larger area of desmin than ISG (p<0.05). It was found a decrease in laminin comparing IUSG to IG. However, laminin area was higher in ISG than all groups (p<0.05). UST isolated or in combination with stretching influenced gastrocnemius regeneration in different manners. While stretching applied isolated enhanced gastrocnemius regeneration noticed by the increase in laminin area, in combination with TUS strengthened the muscle healing rising desmin area.

RESUMEN: El objetivo de este estudio fue evaluar los efectos del estiramiento y la ecografía en los contenidos de desmina y laminina del músculo de rata después de la lesión. Ratas Wistar macho (n = 35, 8-9 semanas de edad, 271 ± 14 g de peso corporal) se dividieron en cinco grupos: grupo de control (CG) (n = 03); Grupo lesionado (GL) (n = 8); Lesionado + grupo de ultrasonido (LGU) (n= 8); Lesionado + grupo de estiramiento (LGE) (n = 8); Lesionado + ultrasonido + grupo de estiramiento (LUGE) (n = 8). La aplicación de ultrasonido comenzó 72 horas después de la lesión, usando el modo pulsado al 50 %, 0,5W / cm2, 5 min, una vez al día, durante cinco días consecutivos. El estiramiento manual pasivo se inició el décimo día después de la lesión, con cuatro repeticiones de 30 seg cada una y 30 seg de descanso entre repeticiones, una vez al día, cinco veces por semana, para un total de diez aplicaciones. Las ratas fueron sacrificadas después de 22 días, y se extrajo el músculo gastrocnemio de ambos miembros para la medición morfométrica de desmina y laminina a través de inmunohistoquímica. El análisis se realizó utilizando ANOVA unidireccional Tukey post-hoc para datos paramétricos y Kruskall-Wallis para datos no paramétricos. Los animales LUGE mostraron un área mayor de desmina que LGE (p <0,05). Se encontró una disminución en la laminina comparando LGU con GL. Sin embargo, el área de laminina fue mayor en LGE que en todos los grupos (p <0,05). El tratamiento con ultrasonido aislado o en combinación con estiramiento influyó en la regeneración del músculo gastrocnemio de diferentes maneras. Si bien el estiramiento aplicado, en combinación con tratamiento de ultrasonido, fortaleció el área de desmina, la regeneración del músculo gastrocnemio mejoró por el aumento en el área de laminina aumentando la curación muscular.

Rabdomiossarcoma cutâneo primário de padrão alveolar: relato de caso em adulto jovem / Primary cutaneous alveolar rhabdomyosarcoma: Case report in a young adult

Sarcomas são neoplasias mesenquimais malignas, raras, que acometem, principalmente, crianças e adolescentes. O rabdomiossarcoma, subtipo oriundo da musculatura esquelética, é condição incomum em adultos, acometendo sítios de localização não habitual, crescimento rápido e de difícil tratamento. Apresenta-se caso de adulto jovem com nodulação em lóbulo auricular esquerdo, cuja análise histopatológica e imuno-histoquímica confirmou tratar-se de rabdomiossarcoma alveolar, o qual foi conduzido em conjunto com a Oncologia.

Sarcomas are rare and malignant mesenchymal neoplasms that mainly affect children and adolescents. Rhabdomyosarcoma, a subtype originating from skeletal muscle, is an uncommon condition in adults. It affects sites of unusual location, presents fast growth, and is challenging to treat. We report a case of a young adult with nodules in the left auricular lobe. The histopathological and immunohistochemical analysis confirmed the alveolar rhabdomyosarcoma, and treatment was conducted in association with Oncology.

Sarcomere structure: the importance of desmin protein in muscle atrophy / Estructura de sarcómera: la importancia de proteína desmina en atrofia muscular

Knowing the ultrastructure of skeletal muscle is critical to understand how it works under normal situation and the disorders caused by extreme or pathological conditions. Sarcomere is the basic structural unit of striated muscle tissue. An important element of sarcomere architecture are the intermediate filaments, including the desmin protein. Desmin protein contributes to maintenance of cell integrity, efficient transmission of force and mechanochemical signaling within the myocyte. Because of this, desmin protein has constantly been a focus of research that investigates its alterations associated to damage and muscle atrophy under different conditions. The purpose of the following literature review is to describe the basic concepts of muscle ultrastructure, emphasizing the desmin protein role under conditions of muscle disuse atrophy and aging.

Conocer la ultraestructura del músculo esquelético es crítico para entender cómo trabaja bajo situaciones normales y en desórdenes causados por condiciones extremas o patológicas. La sarcómera es la unidad de estructura básica del tejido muscular estriado. Elementos importantes en la arquitectura de la sarcómera son los filamentos intermedios, incluyendo la proteína desmina. La proteína desmina contribuye en mantener la integridad celular, la transmisión eficiente de fuerza y la señalización mecanoquímica dentro del miocito. Debido a lo anterior, la proteína desmina ha sido constante foco de investigación en trabajos que estudian sus alteraciones asociadas a daño y atrofia muscular bajo diferentes condiciones. El propósito de la siguiente revisión de la literatura es describir los conceptos básicos de la ultraestructura muscular, enfatizando en el rol de la proteína desmina bajo condiciones de atrofia muscular por desuso y envejecimiento.

Three days of intermittent stretching after muscle disuse alters the proteins involved in force transmission in muscle fibers in weanling rats

The aim of this study was to determine the effects of intermittent passive manual stretching on various proteins involved in force transmission in skeletal muscle. Female Wistar weanling rats were randomly assigned to 5 groups: 2 control groups containing 21- and 30-day-old rats that received neither immobilization nor stretching, and 3 test groups that received 1) passive stretching over 3 days, 2) immobilization for 7 days and then passive stretching over 3 days, or 3) immobilization for 7 days. Maximal plantar flexion in the right hind limb was imposed, and the stretching protocol of 10 repetitions of 30 s stretches was applied. The soleus muscles were harvested and processed for HE and picrosirius staining; immunohistochemical analysis of collagen types I, III, IV, desmin, and vimentin; and immunofluorescence labeling of dystrophin and CD68. The numbers of desmin- and vimentin-positive cells were significantly decreased compared with those in the control following immobilization, regardless of whether stretching was applied (P<0.05). In addition, the semi-quantitative analysis showed that collagen type I was increased and type IV was decreased in the immobilized animals, regardless of whether the stretching protocol was applied. In conclusion, the largest changes in response to stretching were observed in muscles that had been previously immobilized, and the stretching protocol applied here did not mitigate the immobilization-induced muscle changes. Muscle disuse adversely affected several proteins involved in the transmission of forces between the intracellular and extracellular compartments. Thus, the 3-day rehabilitation period tested here did not provide sufficient time for the muscles to recover from the disuse maladaptations in animals undergoing postnatal development.

Small activating RNA induces myogenic differentiation of rat adipose-derived stem cells by upregulating MyoD

ABSTRACTPurpose:RNA activation (RNAa) is a mechanism of gene activation triggered by promoter-targeted small double stranded RNAs (dsRNAs), also known as small activating RNAs (saRNAs). Myogenic regulatory factor MyoD is regarded as the master activator of myogenic differentiation cascade by binding to enhancer of muscle specific genes. Stress urinary incontinence (SUI) is a condition primarily resulted from urethral sphincter deficiency. It is thus expected that by promoting differentiation of adipose-derived stem cells (ADSCs) into myoblasts by activating MyoD gene through RNAa may offer benefits to SUI.Materials and Methods:Rats ADSCs were isolated, proliferated in vitro, and identified by flow cytometry. Purified ADSCs were then transfected with a MyoD saRNA or control transfected. Real-time polymerase chain reaction (RT-PCR) and western blotting were used to detect MyoD mRNA and protein expression, respectively. Immunocytochemical staining was applied to determine the expression of desmin protein in transfected cells. Cell viability was measured by using CellTiter 96® AQueous One Solution Cell Proliferation Assay kit.Results:Transfection of a MyoD saRNA (dsMyoD) into ADSCs significantly induced the expression of MyoD at both the mRNA and protein levels, and inhibited cell proliferation. Desmin protein expression was detected in dsMyoD treated ADSCs 2 weeks later.Conclusion:Our findings show that RNAa mediated overexpression of MyoD can promote transdifferentiation of ADSCs into myoblasts and may help treat stress urinary incontinence (SUI)–a condition primarily resulted from urethral sphincter deficiency.

Dynamic expression of desmin, α-SMA and TGF-β1 during hepatic fibrogenesis induced by selective bile duct ligation in young rats

We previously described a selective bile duct ligation model to elucidate the process of hepatic fibrogenesis in children with biliary atresia or intrahepatic biliary stenosis. Using this model, we identified changes in the expression of alpha smooth muscle actin (α-SMA) both in the obstructed parenchyma and in the hepatic parenchyma adjacent to the obstruction. However, the expression profiles of desmin and TGF-β1, molecules known to be involved in hepatic fibrogenesis, were unchanged when analyzed by semiquantitative polymerase chain reaction (RT-PCR). Thus, the molecular mechanisms involved in the modulation of liver fibrosis in this experimental model are not fully understood. This study aimed to evaluate the molecular changes in an experimental model of selective bile duct ligation and to compare the gene expression changes observed in RT-PCR and in real-time quantitative PCR (qRT‐PCR). Twenty-eight Wistar rats of both sexes and weaning age (21-23 days old) were used. The rats were separated into groups that were assessed 7 or 60 days after selective biliary duct ligation. The expression of desmin, α-SMA and TGF-β1 was examined in tissue from hepatic parenchyma with biliary obstruction (BO) and in hepatic parenchyma without biliary obstruction (WBO), using RT-PCR and qRT‐PCR. The results obtained in this study using these two methods were significantly different. The BO parenchyma had a more severe fibrogenic reaction, with increased α-SMA and TGF-β1 expression after 7 days. The WBO parenchyma presented a later, fibrotic response, with increased desmin expression 7 days after surgery and increased α-SMA 60 days after surgery. The qRT‐PCR technique was more sensitive to expression changes than the semiquantitative method.

Patologia do bloqueio atrioventricular na cardiomiopatia por depósito de desmina / Atrioventricular block pathology in cardiomyopathy by desmin deposition / Patología de bloqueo auriculoventricular en la miocardiopatía por depósito de desmina

Geralmente, a cardiomiopatia restritiva por deposição de desmina é caracterizada pela restrição ao enchimento diastólico ventricular e por diferentes graus de bloqueio atrioventricular (BAV). Neste relato, são descritas as alterações anatomopatológicas do sistema de condução cardíaco relacionadas ao BAV. O nó sinusal, o nó compacto e o feixe penetrante (feixe de His) não apresentavam anormalidades, entretanto, havia extensa fibrose das porções terminais do feixe ramificante e do início dos feixes esquerdo e direito, no topo do septo ventricular. A patogenia dessa substituição fibrosa é provavelmente a mesma que origina a extensa fibrose do miocárdio ventricular contrátil, e permanece por ser elucidada.

Generally, restrictive cardiomyopathy due to desmin deposition is characterized by restriction to ventricular diastolic filling and different degrees of atrioventricular block (AVB). In this report, we describe the pathological changes of the cardiac conduction system related to AVB. The sinus node, the compact node, and the penetrating bundle (bundle of His) had no abnormalities, however, there was extensive fibrosis of the terminal portions of the branching bundle and the beginning of the left and right bundles at the top of the ventricular septum. The pathogenesis of this fibrous replacement is probably the same that leads to extensive fibrosis of the working ventricular myocardium, and remains to be elucidated.

En general, la miocardiopatía restrictiva, debido a la deposición de desmina se caracteriza por la restricción de llenado diastólico ventricular y por los distintos grados de bloqueo auriculoventricular (BAV). En este informe, se describen los cambios anatómicos y patológicos del sistema de conducción cardiaco relacionado con BAV. El nodo sinusal, el nodo compacto y haz penetrante (haz de His) no tuvo alteraciones, sin embargo, había fibrosis extensa de las porciones terminales del haz en porción ramificante y del comienzo de los haces izquierda y derecha, en la parte superior del tabique ventricular. La patogenia de esta sustitución fibrosa es probablemente la misma que origina la fibrosis extensa del miocardio ventricular contráctil, y queda por dilucidar.

Nemaline myopathy: clinical, histochemical and immunohistochemical features / Miopatia nemalínica: achados clínicos, histoquímicos e imuno-histoquímicos

Nemaline myopathy (NM) is a congenital disease that leads to hypotonia and feeding difficulties in neonates. Some cases have a more benign course, with skeletal abnormalities later in life. We analyzed a series of eight patients with NM obtained from a retrospective analysis of 4300 muscle biopsies. Patients were classified as having the typical form in five cases, intermediate form in two cases and severe form in one case. Histochemical analysis showed mixed rods distribution in all cases and predominance of type I fibers in five cases. Immunohistochemical analysis showed abnormal nebulin expression in all patients (four heterogeneous and four absent), homogeneous desmin expression in four cases, strongly positive in three and absent in one, fast myosin expression in a mosaic pattern in six cases and absent in two cases. There was no specific relation between these protein expression patterns and the clinical forms of NM.

Miopatia nemalínica (NM) é uma doença congênita que leva a hipotonia e dificuldade de sugar em neonatos. Alguns casos possuem uma evolução benigna, com deformidades ósseas tardias. Nós analisamos uma série de oito pacientes com NM obtidos da análise retrospectiva de 4300 biópsias musculares. Os pacientes foram classificados como forma típica em cinco casos, forma intermediária em dois casos e forma severa em um caso. Análise histoquímica mostrou distribuição mista dos rods em todos os casos e predominância de fibras tipo I em cinco casos. Análise imuno-histoquímica mostrou expressão anormal da nebulina em todos os pacientes (quatro heterogênea e quatro ausente), expressão homogenea da desmina em quatro casos, fortemente positiva em tres e ausente em um, expressão da miosina (rápida) com padrão em mosaico em seis casos e ausente em dois casos. Não há relação específica entre a expressão destas proteínas e as formas clínicas da NM.

Desmin-related restrictive cardiomyopathy / Cardiomiopatia restritiva por depósito de desmina

As cardiomiopatias restritivas podem possuir diversas etiologias, entre elas destacam-se as doenças de depósito por diferentes materiais, como por desmina. As desminopatias são patologias incomuns, que evoluem com distúrbios de condução, miopatias periféricas e disfunção ventricular. O presente relato descreve paciente com bloqueio átrio ventricular total como evento inicial, sendo acometido posteriormente por alterações musculares esqueléticas e insuficiência cardíaca. Na investigação foi definido diagnóstico de cardiomiopatia restritiva por acúmulo de desmina.

Restrictive cardiomyopathies may have different etiologies, among which we can point out storage diseases by accumulation of different materials such as desmin. Desminopathies are uncommon diseases that progress with conduction abnormalities, peripheral myopathies, and ventricular dysfunction. The present report describes a patient with complete atrioventricular block as the initial event; he later developed skeletal muscle alterations and heart failure. The investigation led to the diagnosis of restrictive cardiomyopathy due to desmin accumulation.