Regenerative and Resorbable PLA/HA Hybrid Construct for Tendon/Ligament Tissue Engineering.

Tendon and ligament shows extremely limited endogenous regenerative capacity. Current treatments are based on the replacement and or augmentation of the injured tissue but the repaired tissue rarely achieve functionality equal to that of the preinjured tissue. To address this challenge, tissue engineering has emerged as a promising strategy. This study develops a regenerative and resorbable hybrid construct for tendon and ligament engineering. The construct is made up by a hollow poly-lactic acid braid with embedded microspheres carrying cells and an anti-adherent coating, with all the parts being made of biodegradable materials. This assembly intends to regenerate the tissue starting from the interior of the construct towards outside while it degrades. Fibroblasts cultured on poly lactic acid and hyaluronic acid microspheres for 6 h were injected into the hollow braid and the construct was cultured for 14 days. The cells thus transported into the lumen of the construct were able to migrate and adhere to the braid fibers naturally, leading to a homogeneous proliferation inside the braid. Moreover, no cells were found on the outer surface of the coating. Altogether, this study demonstrated that PLA/HA hybrid construct could be a promising material for tendon and ligament repair.

Consideraciones éticas en el diagnóstico presintomático de ataxias espinocerebelosas autosómico dominantes / Ethical considerations in presymptomatic diagnosis of autosomal dominant spinocerebellar ataxias

Introducción: Existe información limitada de la realización de diagnóstico presintomático en ataxias espinocerebelosas (SCA) autosómicas dominantes. La llegada del diagnóstico molecular, además de brindar la posibilidad de realizar identificación en pacientes portadores de distintas enfermedades, permitió también la posibilidad de detectar enfermedades incluso antes de su presentación. Esto atrajo la atención sobre las implicaciones éticas que deberían ser consideradas en estos sujetos, con la finalidad de salvaguardar su bienestar físico y psicológico. Desarrollo: La SCA está compuesta por un grupo de trastornos neurodegenerativos con patrón de herencia autosómico dominante. Existen pocas publicaciones que describen el proceso de asesoramiento y los lineamientos considerados durante el proceso de diagnóstico presintomático. El número de integrantes de los equipos multidisciplinarios, sus áreas de especialidad y número de sesiones durante el asesoramiento es variable en cada uno de los trabajos analizados. Sin embargo, las bases para su realización tienen origen en documentos comunes, en los cuales algunos de los autores han participado en fechas más recientes. Conclusiones: El diagnóstico presintomático debe ser realizado bajo lineamientos que salvaguarden el bienestar de los sujetos. Sería recomendable que el diagnóstico de SCA sea realizado solo a pacientes con clínica sugestiva, mayores de 18 años y con un riesgo mínimo del 50%. Deben estar disponibles esquemas de asesoramiento genético en todos aquellos centros que pretenden realizar diagnóstico de SCA antes de la presentación de síntomas (AU)

Introduction: Information on achieving presymptomatic diagnosis of spinocerebellar ataxia (SCA) is limited. The advent of molecular diagnosis makes it possible to identify the carriers of different diseases and has also introduced the prospect of detecting diseases even before their onset. This has drawn attention to the ethical implications that must be considered in these subjects with a view to preserving their physical and psychological well-being. Development: SCA is composed of a group of neurodegenerative disorders with autosomal dominant inheritance. Only a few publications have described the genetic counselling processes and guidelines to be followed during the process of presymptomatic diagnosis (PSD). The size of the multidisciplinary teams, their areas of expertise, and the number of counselling sessions are different for each of the studies analysed here. However, the basis of presymptomatic diagnosis originates in common guidelines to which members of our team have contributed recently. Conclusion: Presymptomatic diagnosis should be performed according to guidelines that safeguard the subjects’ welfare. The diagnostic process is only recommended for patients over 18 years old with symptoms suggesting SCA, and a minimum risk of 50%. Genetic counselling programmes must be available in all centres that offer presymptomatic diagnosis of SCA (AU)

Ethical considerations in presymptomatic diagnosis of autosomal dominant spinocerebellar ataxias. / Consideraciones éticas en el diagnóstico presintomático de ataxias espinocerebelosas autosómico dominantes.

INTRODUCTION: Information on achieving presymptomatic diagnosis of spinocerebellar ataxia (SCA) is limited. The advent of molecular diagnosis makes it possible to identify the carriers of different diseases and has also introduced the prospect of detecting diseases even before their onset. This has drawn attention to the ethical implications that must be considered in these subjects with a view to preserving their physical and psychological well-being. DEVELOPMENT: SCA is composed of a group of neurodegenerative disorders with autosomal dominant inheritance. Only a few publications have described the genetic counselling processes and guidelines to be followed during the process of presymptomatic diagnosis (PSD). The size of the multidisciplinary teams, their areas of expertise, and the number of counselling sessions are different for each of the studies analysed here. However, the basis of presymptomatic diagnosis originates in common guidelines to which members of our team have contributed recently. CONCLUSION: Presymptomatic diagnosis should be performed according to guidelines that safeguard the subjects' welfare. The diagnostic process is only recommended for patients over 18 years old with symptoms suggesting SCA, and a minimum risk of 50%. Genetic counselling programmes must be available in all centres that offer presymptomatic diagnosis of SCA.

SEVERE HYDROCEPHALUS, KIDNEY AND SKELETAL ANOMALIES IN A FEMALE PATIENT WITH MILD NEUROLOGICAL ALTERATIONS.

The appearance of untreated severe hydrocephalus with long-term survival is infrequent; here we report a case with these characteristics, mild neurological alterations and kidney and skeletal anomalies. A female patient showed severe hydrocephalus (initially mistaken with hydranencephaly) at 4 years old and left kidney ectopia (initially mistaken with renal agenesis); however, she was derived to the neurology service until she was 12 years old, when she began to present migraine and seizures. At 13 years old the patient was diagnosed with arrested hydrocephalus secondary to aqueduct stenosis, and the seizures worsen thereafter from atonic seizures to complex partial seizures (at 14 years old), presenting generalized seizures at 15 years old. At 17 years old, the seizures were more frequent despite the anticonvulsant treatment and also presented automations, she was also diagnosed with genu recurvatinn and scoliosis. The seizures finally diminished and partially controlled at 19 years old. Despite a cerebral mantle < 2.0 cm at the computer tomography, the patient always presented a satisfactory intellectual development. In this case, the relatively good and long evolution of the severe hydrocephalus is probably related with the late-onset of the disease that permitted a better development of the brain; however, the worsening of the seizures after the hydrocephalus arrested, suggests that arrest is not necessarily associated with a compensation and better evolution of the disease, at least at the beginning of the process. The presence of kidney ectopia and skeletal alterations did not associate with a known genetic disease, however a possible inheritance mechanism is not discarded.

Fibrin-chitosan composite substrate for in vitro culture of chondrocytes.

The aim of this study was to develop a biocompatible monolayer substrate based on fibrin and chitosan for in vitro culture of chondrocytes. Fibrin-chitosan composite substrates combined the proved cell adhesion properties of fibrin with the hydrophilicity and poor adhesion capacity of chitosan. Chitosan microspheres were produced by coacervation method, agglomerated within a fibrin network and subsequently crosslinked with genipin. The composite substrate was stable for 28 days of culture due to the high crosslinking density. Human chondrocytes cultured on the composite substrate were viable during the culture period. At the end of culture time (28 days) the composite substrate showed low cellular proliferation, 41% more collagen type II and 13% more production of sulfated glycosaminoglycans with respect to the amounts found at 14 days. The study revealed that dedifferentiated chondrocytes cultured in monolayer on the composite substrate can re-acquire characteristics of differentiated cells without using three-dimensional substrates or chondrogenic media.

Gelatin microparticles aggregates as three-dimensional scaffolding system in cartilage engineering.

A three-dimensional (3D) scaffolding system for chondrocytes culture has been produced by agglomeration of cells and gelatin microparticles with a mild centrifuging process. The diameter of the microparticles, around 10 µ, was selected to be in the order of magnitude of the chondrocytes. No gel was used to stabilize the construct that maintained consistency just because of cell and extracellular matrix (ECM) adhesion to the substrate. In one series of samples the microparticles were charged with transforming growth factor, TGF-ß1. The kinetics of growth factor delivery was assessed. The initial delivery was approximately 48 % of the total amount delivered up to day 14. Chondrocytes that had been previously expanded in monolayer culture, and thus dedifferentiated, adopted in this 3D environment a round morphology, both with presence or absence of growth factor delivery, with production of ECM that intermingles with gelatin particles. The pellet was stable from the first day of culture. Cell viability was assessed by MTS assay, showing higher absorption values in the cell/unloaded gelatin microparticle pellets than in cell pellets up to day 7. Nevertheless the absorption drops in the following culture times. On the contrary the cell viability of cell/TGF-ß1 loaded gelatin microparticle pellets was constant during the 21 days of culture. The formation of actin stress fibres in the cytoskeleton and type I collagen expression was significantly reduced in both cell/gelatin microparticle pellets (with and without TGF-ß1) with respect to cell pellet controls. Total type II collagen and sulphated glycosaminoglycans quantification show an enhancement of the production of ECM when TGF-ß1 is delivered, as expected because this growth factor stimulate the chondrocyte proliferation and improve the functionality of the tissue.

Wide clinical spectrum in Zimmermann-Laband syndrome.

Gingival fibromatosis can be present as an isolated form or be part of a genetic disease. The Zimmermann-Laband syndrome (ZLS) is a rare disorder inherited as an autosomal dominant fashion, clinically characterized by gingival fibromatosis, bulbous soft nose, thick floppy ears, nail dysplasia, joint hyperextensibility, hepatosplenomegaly, skeletal anomalies and occasional mental retardation. We studied a girl aged five years with clinical and radiological features of the ZLS, additionally she presented deafness not previously described in the ZLS, as only partial hearing loss was reported in some patients. The father presented some facial features suggestive of ZLS, nevertheless he did not have gingival fibromatosis or hypertrichosis. We suggest that this case supports that ZLS can be part a contiguous genes syndrome or be consequence ofa gene mutation with wide variable expression. The present report supports that ZLS has a wide clinical spectrum.

SED-brachydactyly and distinctive speech: report of two new cases.

We describe two unrelated patients and the mother of one of them showing clinical and radiological features as those previously described in the spondyloepiphyseal dysplasia-brachydactyly and distinctive speech (SED-BDS, also named Fantasy Island syndrome or Tattoo dysplasia) clinically characterized by short stature with acral shortness, distinctive face, mild blepharophimosis, upslanted palpebral fissures, abundant eyebrows and eyelashes, thick and abundant hair and coarse voice; and radiologically by brachymetacarpalia, brachymetatarsalia and brachyphalangia of all fingers and toes, short and broad long bones with normal morphology and small pelvis. The clinical and radiological features present in mother and son suggest a probable autosomal dominant mode of inheritance and variable expressivity.

Influence of the substrate's hydrophilicity on the in vitro Schwann cells viability.

A series of polymeric biomaterials including poly (methyl acrylate) (PMA), chitosan (CHT), poly(ethyl acrylate) (PEA), poly(hydroxyethyl acrylate) (PHEA), and a series of random copolymers containing ethyl acrylate and hydroxyethyl acrylate monomeric units were tested in vitro as culture substrates and compared for their impact on the proliferation and expansion of Schwann cells (SCs). Immunocytochemical staining assay and scanning electron microscopy techniques were applied to perform a quantitative analysis to determine the correct maintenance of the cultured glial cells on the different biomaterials. The results strongly suggest that cell attachment and proliferation is influenced by the substrate's surface chemistry, and that hydrophobic biomaterials based on PMA, PEA, and the copolymers PEA and PHEA in a narrow composition window are suitable substrates to promote cell attachment and proliferation of SCs in vitro.

Zimmermann-Laband syndrome: further clinical delineation.

Zimmermann-Laband syndrome (ZLS) is an autosomal dominant disorder characterized by gingival fibromatosis, absent or dysplastic distal phalanges, vertebral defects, hepatosplenomegaly, hypertrichosis and sometimes mental retardation. We describe two unrelated patients, a girl aged 9 years and a boy 11 months whose clinical and radiological findings permit us to diagnose the ZLS. Body overgrowth, present in both patients, was identified as a main clinical feature not previously reported as well as the presence in neuroimaging studies of a cavernous hemangioma on the frontal and the left cerebellar regions in the boy. The girl also presented important radiological characteristics such as broad medulary canals and metaphyses of long bones, thin cortices, broad ribs, accelerated skeletal maturation as well as high intelligence level. A wide clinical spectrum in ZLS is also considered.

A non-sense mutation in the corneodesmosin gene in a Mexican family with hypotrichosis simplex of the scalp.

BACKGROUND: Hypotrichosis simplex of the scalp (HSS; MIM 146520) is a rare autosomal dominant form of non-syndromic alopecia that affects men and women equally. Up to now, only a small number of families with HSS have been reported. The affected individuals experience a diffuse progressing hair loss from childhood to adulthood that is confined to the scalp. Recently, HSS has been mapped to the short arm of chromosome 6 (6p21.3), allowing mutations in the corneodesmosin gene (CDSN) to be identified as the cause of the disorder. To date, two stop mutations have been found in three unrelated families with HSS of different ethnic origin. OBJECTIVES: To describe the first HSS-family with Latin American (Mexican) background comprising 6 generations and to identify a mutation in the CDSN gene. PATIENTS/METHODS: The patients were examined by a clinician and blood samples were taken. After DNA extraction, sequencing analysis of the CDSN gene and restriction enzyme analysis with PsuI were performed. RESULTS: By direct sequencing of the two exons of the CDSN gene, a nonsense mutation was identified in the index patient in exon 2, resulting in a premature stop codon (Y239X). The mutation co-segregates perfectly in the family with the disease and was not found in 300 control chromosomes using a restriction enzyme analysis with PsuI. CONCLUSIONS: A nonsense mutation was identified in the first family with HSS of Latin American ethnical background. Our data provide molecular genetic evidence for a 3rd stop mutation in exon 2 of the CDSN gene being responsible for HSS. All to date known nonsense mutations responsible 3 for HSS are clustered in a region of 40 amino acids which is in accordance with a dominant negative effect conferred by aggregates of truncated CDSN proteins.

Familial iridogoniodysgenesis and skeletal anomalies: a probable new autosomal recessive disorder.

Three sibs with congenital glaucoma, skeletal anomalies, and peculiar facial appearance were studied. At birth, enlarged eyes and corneae were present in the proposita and her two brothers due to congenital glaucoma secondary to iridogoniodysgenesis (IGD). The purpose of this article is to describe the second familial case with IGD and skeletal anomalies as the family previously described by García-Cruz et al. in 1990, corroborating this new distinct dysmorphic syndrome with probable autosomal recessive inheritance.

Second female case of Myhre syndrome.

Myhre syndrome is a rare disorder characterized by low birthweight, short stature, mental retardation, facial dysmorphism (blepharophimosis, midfacial hypoplasia, prognathism), heart anomalies, muscle hypertrophy, decreased joint mobility and deafness. To date 11 male cases and only one female case have been reported. This paper describes the second female case and compares the clinical and radiological findings between female and male patients.

Complete achromatopsia associated with skeletal anomalies: a new autosomal recessive syndrome.

Complete achromatopsia associated with skeletal anomalies: a new autosomal recessive syndrome: Achromatopsia or rod monochromatism is the complete absence of color discrimination, with an estimated frequency of 1 in 100,000. To date the McKusick Catalogue includes more than 10 entities related to Achromatopsia. This paper describes four Mexican sibs with a stationary rod monochromatism, associated with long fingers and toes, hypothenar and thenar hypoplasia and pes planus, suggesting a new genetic entity probably inherited in an autosomal recessive mode.

Myhre syndrome: first female case.

A 15 year old girl with the Myhre type growth-mental retardation syndrome is described. This is the first female case reported in the literature. The inheritance pattern of this condition is not clear.

A variant example of familial Floating-Harbor syndrome?

The Floating-Harbor syndrome (FHS) is clinically characterized by short stature, retarded speech development, delayed bone age, typical facies, bulbous nose, wide columella, thin lips. Four cases with celiac disease have been described previously. In two other cases, autosomal dominant inheritance has been suggested. We describe a boy aged 2 years 11 months with clinical features of FHS and celiac disease. His mother also presents minor phenotypical characteristics, suggesting that the present observation corresponds to a variant example of familial FHS.

Inherited hypertrichoses.

Hypertrichosis is a rare condition characterized by excessive growth of hair (terminal, vellus or lanugo) in areas of the body that are not predominantly androgen dependent, and it is independent of age, race or sex. It can be congenital, late-onset, generalized, localized, inherited or acquired. More than 50 different OMIM entries related to hypertrichosis exist, few of them with a localized gene locus or with a candidate gene. The review of generalized hypertrichoses from a historical point of view, including a review of their clinical and genetic features, shows heterogeneity with at least nine different entities. A short analysis of other forms of hypertrichosis is presented.

Del Xq23 in a mosaic Turner female: molecular and cytogenetic studies.

We report a Turner patient aged 22 years with a 45,X/46,X,del(X)(q23) karyotype. Late replication studies showed preferential inactivation of the deleted X chromosome; FISH studies with a probe for total human telomeres showed hybridisation signal in the telomeres on both the normal and the deleted X chromosomes. Microsatellite analysis in the proposita and her family permitted us to conclude to the maternal origin of the deleted X chromosome, and to detect using the marker DXS1106 (Xq22) a probable meiotic recombination event above the breakage point suggesting that the deletion occurred underneath this point. The mild Turner stigmata may be explained by the 45,X cell line, and the gonadal dysgenesis probably by a partial deletion of the gonadal dysgenesis region Xq13-q23 (excluding Xq22).

Further clinical delineation in trisomy 1q32 syndrome.

A male newborn with multiple congenital abnormalities was studied. Clinically, he showed prominent forehead, facial dysmorphism, ear malformations, congenital heart defect and limb anomalies. The cytogenetic studies demonstrated a karyotype 46,XY, der(18) t(1;18)(q32;p11.3)pat with partial trisomy 1q32-qter and a monosomy 18p. The patient displayed clinical features of trisomy 1q but not of monosomy 18p. There are around 80 reports of trisomy 1q32. The purpose of this paper is to describe the first case of a translocation involving 1q and 18p chromosome breakpoints. Additional findings detected in the propositus permit us a further delineation of the trisomy 1q syndrome.