Raising obstetricians' awareness of spinal muscular atrophy: towards early detection and reproductive planning

Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder that is caused by degeneration of α motor neurons in the spinal cord anterior horns. This degeneration can lead to progressive atrophy of proximal muscles, weakness, respiratory failure and death in severe cases. SMA is the most common neuromuscular disease of childhood and one of the main causes of infant death, with no cure in sight. This review highlights the impact of the disease in families, summarizes genetics and ultrasound advances, discusses how obstetricians can work towards its early detection and explores the options for reproductive planning.

Platelet adhesion and human umbilical vein endothelial cell cytocompatibility of biodegradable segmented polyurethanes prepared with 4,4'-methylene bis(cyclohexyl isocyanate), poly(caprolactone) diol and butanediol or dithioerythritol as chain extenders

Biodegradable segmented polyurethanes were prepared with poly(caprolactone) diol as a soft segment, 4,4'-methylene bis(cyclohexyl isocyanate) (HMDI) and either butanediol or dithioerythritol as chain extenders. Platelet adhesion was similar in all segmented polyurethanes studied and not different from Tecoflex® although an early stage of activation was observed on biodegradable segmented polyurethane prepared with dithioerythritol. Relative viability was higher than 80% on human umbilical vein endothelial cells in contact with biodegradable segmented polyurethane extracts after 1, 2 and 7 days. Furthermore, both biodegradable segmented polyurethane materials supported human umbilical vein endothelial cell adhesion, spreading, and viability similar to Tecoflex® medical-grade polyurethane. These biodegradable segmented polyurethanes represent promising materials for cardiovascular applications.

Evaluation of fetal nuchal translucency in 98 pregnancies at risk for severe spinal muscular atrophy: possible relevance of the SMN2 copy number

OBJECTIVE

To study fetal nuchal translucency (NT) thickness as a possible early marker in fetuses at risk for severe spinal muscular atrophy (SMA). To investigate the significance of the survival motor neuron (SMN) 2 gene copy number in affected fetuses.

METHODS

We performed 2D-ultrasound in 98 pregnancies at risk for SMA, all of which underwent prenatal molecular testing of the SMN1 gene. Crown-rump length (CRL) and NT measurements were obtained in all cases before chorionic villus sampling. Fetuses were diagnosed as healthy, carriers or affected according to the SMN1 molecular testing results. SMN2 copies were also tested in all affected fetuses.

RESULTS

Nineteen fetuses were predicted to be affected due to the absence of the SMN1 gene, 18 of which had two SMN2 copies. Mean CRL and NT values did not differ between healthy, carrier and affected fetuses. In the remaining affected case who had only one SMN2 copy, the ultrasound examination showed a NT value of 4.98 mm and findings compatible with hypoplastic left heart.

CONCLUSIONS

Most affected SMA fetuses have normal NT values. Our findings support the idea that SMN2 copy number in SMA fetuses is relevant for the development of congenital heart defects and increased NT values.

Bioactive polymeric systems with platelet antiaggregating activity for the coating of vascular devices

The preparation, characterization, and analysis of physicochemical and biological properties of a new bioactive polymer system, based on a copolymer of an acrylic derivative of triflusal (a molecule with chemical structure related to aspirin with antiaggregating activity for platelets) is described and evaluated as thin bioactive coating for vascular grafts and coronary stents. The acrylic monomer derived from triflusal (THEMA) provides random copolymers when it is polymerized with butyl acrylate (BA), according to their reactivity ratios, r(THEMA) = 1.05 and r(BA) = 0.33. The copolymer THBA70, containing a molar composition f(THEMA) = 0.45 and f(BA) = 0.55 presents the optimal properties of stability, flexibility, and adhesion, with a T(g) = 21 ± 2 °C, to be applied as bioactive and biostable coatings for vascular grafts and coronary stents. Thin films of this copolymer system present an excellent biocompatibility and a good inherent antiaggregant activity for platelets.

Adherence to disease-modifying therapies in spanish patients with relapsing multiple sclerosis: two-year interim results of the global adherence project

The post-marketing international Global Adherence Project investigated adherence to disease-modifying therapy for relapsing-remitting multiple sclerosis. We report adherence data from the first 2 years in the Spanish subset of patients (n = 254 at baseline). The overall adherence rate was 85.4%. Patients taking intramuscular (IM) interferon-β (IFNβ)-1a were significantly more adherent (96.4%) compared with patients taking subcutaneous (SC) IFNβ-1a 22 μg (79.1%; p = 0.0064), SC IFNβ-1a 44 μg (79.6%; p = 0.0064) and glatiramer acetate (82.7%; p = 0.0184). At year 1 (n = 142), the overall adherence rate was 86.6%. Patients on IM IFNβ-1a were significantly more adherent than patients on SC IFNβ-1a 22 μg (93.9 vs. 66.7%; p = 0.0251). At year 2 (n = 131), the overall adherence rate was 82% (87.5% for IM IFNβ-1a, 80.0% for SC IFNβ-1a 22 μg, 77.8% for SC IFNβ-1a 44 μg, 85.2% for IFNβ-1b, and 80.0% for glatiramer acetate). In conclusion, adherence remained high among all disease-modifying therapies over the first 2 years of the study and was significantly higher for IM IFNβ-1a, at visit 1, compared with SC IFNβ-1a.

[Endovascular management of acute complications of type B aortic dissection]

BACKGROUND

Type B aortic dissection is usually managed by intensive care medical therapy and surgery is reserved for treating the complications that can occur during the evolution of a case.

AIM

To assess the endovascular management of acute complications of type B aortic dissection and the closure of the intimal defect and aortic false lumen.

MATERIAL AND METHODS

Retrospective analysis of 8 consecutive patients aged 40 to 57 years (seven males) treated for acute complications in the initial episode of a type B aortic dissection between August 2006 and July 2008.

RESULTS

Six/eight were known hypertensive patients. The indications for surgery were intractable pain in one, hypertension refractory to treatment in two and distal hypoperfusion in five. Five patients required covering of the left subclavian artery ostium, without need for surgical repair. One patient was subjected to renal angioplasty and stenting. Technical success was achieved in all cases, with complete closure of the proximal aortic tear and thoracic aortic false lumen, although 7 of patients had a persistent distal aortic false lumen. One case had a transient lower limb paraparesis. No patient died.

CONCLUSIONS

Endovascular treatment is effective in closing the aortic tear as well as the thoracic aortic false lumen in aortic type B dissections with a low complication rate. Due to the high frequency of distal aortic false lumen persistence, it is not a definitive treatment for this condition but it is useful for the acute complications of the initial phase of type B aortic dissection.

Biocompatibility of alendronate-loaded acrylic cement for vertebroplasty

This paper reports a biological evaluation of a non-resorbable acrylic cement loaded with alendronate for the treatment of osteoporotic vertebral compression fractures. The cement formulation was based on polymethyl methacrylate and acrylic monomers; one of these had covalently linked vitamin E residues. The same cement in the absence of alendronate was used as a control. The setting of the charged cement presented a maximum polymerization temperature of 44°C, a setting time of 24 min, a residual monomer content lower than 3 wt.%, a compressive strength of 99±10 MPa and an elastic modulus of 1.2±0.2 GPa. Cytotoxicity studies using human osteoblast cultures revealed that the leachable substances of the alendronate loaded cement collected between 1 and 7 days decreased cell viability to values lower than 80%. However, morphological changes and cellular damage in cells produced by the extracts decreased with the leak time. Cell adhesion and growth on charged cement was significantly lower than on the control. Implantation of the cement paste in the intra-femoral cavity of rabbits showed that initially the osteogenic activity was evident for the cement charged with alendronate, and the osteosynthesis process took place mainly in the trabeculae and was manifested by the presence of a non-mineralised osseous spicule. The interface between material and adjacent bone tissue was initially characterized by a variable fibrous response that in many cases it appeared reduced to thin connective tissue after a 24-week-period.

[Global adherence project to disease-modifying therapies in patients with relapsing multiple sclerosis: 2-year interim results]

BACKGROUND

In this article we report adherence data from the first 2 years in a subset of patients from the Global Adherence Project (GAP; n=2,648) in Spain.

METHODS

A questionnaire assessing adherence to Disease-modifying therapies (DMTs), was distributed annually to patients and their treating neurologists. Non-adherence was defined as missing a DMT injection or changing a dose in the four weeks prior to completing the survey. Patients signed informed consent and Ethics Committees approved annual follow-ups, visit 1 (V1) and visit 2 (V2) in 15 out of 18 centres in Spain.

RESULTS

A total of 254 patients were enrolled in Spain. Patients had a mean age of 37.9 years and 70.4% were female, and had been on their treatment for a median time of 28 months, and the overall adherence rate was 85.4%. Patients taking intramuscular interferon beta (IFNB)-1a (Avonex®) were significantly more adherent (94.6%) compared with patients taking subcutaneous (s.c.) IFNB-1a 22.g (Rebif®22) (79.1%; p=0.0064), s.c. IFNB-1a 44.g (Rebif®44) (79.6%; p=0.0064) and glatiramer acetate (GA) (82.7%; p=0.0184). At V1 (n=142), the overall adherence rate was 86.6% and patients on Avonex® were significantly more adherent than patients on Rebif®22 (93.9% versus 66.7%; p=0.0251). At V2 (n=131), the overall adherence rate was 82.4% (Avonex®, 87.5%; Rebif®22, 80%; Rebif®44, 77.8%; Betaferon®, 85.2%, and Copaxone®, 80%) without significant differences.

CONCLUSIONS

Adherence remained high over the first 2 years of the study. It was highest with Avonex®, being significant on first assessment, after 40.5 months of therapy, on average compared with other DMTs and at year 1 compared with Rebif®22.

[Long-term results of the treatment of urinary incontinence with bulbar implantation of artificial urinary sphincter in men: a single-center experience]

OBJECTIVE

To report the functional results and morbidity after implantation of bulbar artificial urinary sphincter (AUS) in incontinent men with at least 5 years of follow-up.

PATIENTS AND METHODS

The files of patients treated between 1984 and 2003 by setting up a SAU at bulbar location were reviewed. The following data were recorded: age, etiology of incontinence, intra-operative complications. To evaluate the results on continence, patients were seen at 1, 3, 6 and 12 months, and yearly thereafter.

RESULTS

Overall, 159 men implanted with an AUS were included. The median age was 68.4 years and the median follow-up was 69 months. The etiology of incontinence was a prostate surgery in 83% of cases. The five-year rates of continence and satisfaction were 74.2% (n=118) and 92% (n=140), respectively. The five-year rates of infections and erosions were 4.4% and 9.4%, respectively. In case of previous radiotherapy, the rate of erosion at 5 years was 22.2%. The rate of atrophy and urethral mechanical failure at 5 years was 7.5% and 23.6%, respectively. The rate of reoperation at 5 years was 41.5%.

CONCLUSION

Our results confirm that the AUS is still the standard treatment for male with urinary incontinence due to intrinsic sphincter deficiency. Minimally invasive therapies are being developed that could overcome the mechanical failures and offer an alternative in case of primary or even secondary failure of the AUS.

The intracarotid amobarbital or Wada test: unilateral or bilateral?

OBJECTIVE

In the Netherlands, presurgical screening for temporal lobe epilepsy (TLE) includes the intracarotid amobarbital procedure (IAP), consisting of two consecutive injections of amobarbital, ipsilateral and contralateral to the epileptic focus. We studied whether a bilateral IAP has added value to a unilateral, ipsilateral IAP.

METHODS

This population-based study included 183 consecutive patients referred for screening for TLE surgery who underwent bilateral IAP. Using multivariable modeling, we assessed the added value of bilateral IAP on the decision for surgery, resection size, amygdalohippocampectomy, post-operative seizure freedom, memory performance, and IQ change.

RESULTS

Given the results from the unilateral IAP, the bilateral IAP had added prognostic value for postoperative change in verbal memory (P < 0.01) and verbal IQ (P < 0.01), especially if patients had a left-sided focus. In contrast, information provided by the contralateral IAP was not associated with decision-making or surgical strategy.

CONCLUSIONS

A bilateral IAP has added value in predicting post-operative verbal memory and IQ. A bilateral IAP is currently not used to guide surgical strategy, but may be used for this purpose when verbal capacity is of particular concern in patients with a left-sided focus. In other cases, IAP is best performed unilaterally.

The preparation of high conversion polymeric systems containing eugenol residues and their rheological characterization

Copolymeric systems bearing eugenol covalently linked to the macromolecular chains have been prepared and characterised in terms of thermal, rheological and in vitro behaviour. Eugenyl methacrylate (EgMA) and ethoxyeugenyl methacrylate (EEgMA) were polymerized and copolymerized with ethyl methacrylate (EMA) in a wide range of feed composition by bulk at high conversion. Glass transition temperature (Tg) increased with the content of EgMA in the copolymer whereas Tg decreased with the content of EEgMA. The presence of any of the eugenyl monomers in the copolymer increased the thermal stability of the materials. Rheological analysis showed that EMA-co-EgMA copolymers present a higher density of crosslinking or entanglements among the chains compared with EMA-co-EEgMA materials, and copolymers containing more than 40% EgMA exhibited a pseudo-solid like behaviour with G' relatively independent of the frequency. The average molecular weight between cross-links (Mc) for the latter copolymers was in the order of 10(4) Da. For EEgMA copolymers, tan delta was lower than unity and G' showed a gradual and slight dependency with frequency over the whole range of composition. In vitro behaviour showed a higher hydrophilicity of the EEgMA containing copolymers manifested in higher water sorption values, lower water contact angle values and higher surface free energy due to an increase in polarity. All systems presented a good cytocompatibility with human fibroblasts assessed through direct and indirect assays.

Self-curing acrylic formulations with applications in intervertebral disk restoration: drug release and biological behaviour

New injectable acrylic formulations have been prepared to be applied in restoration processes for intervertebral disks (IVDs). The solid phase of the formulations is composed of poly(methyl methacrylate) (PMMA), incorporating in some cases chondroitin sulphate (CS) as a regenerative bioactive molecule, whereas the liquid phase is constituted by an amphiphilic macromonomer (MT), 2-hydroxyethyl methacrylate (HEMA) and, in some formulations, acrylic acid (AA). The curing parameters and the mechanical properties of the IVD formulations make them excellent candidates for intervertebral application. In vitro and in vivo evaluation of the prepared IVD formulations is described in terms of CS release, surface analysis after immersion in SBF solutions, and biocompatibility studies based on MTT assay and Alamar blue test, as well as in vivo implantation in female Wistar rats, by injection of the IVD formulations followed by histological evaluations to assess tissue response.

Fast and slow myosins as markers of muscle injury

Objective:

The diagnosis of muscular lesions suffered by athletes is usually made by clinical criteria combined with imaging of the lesion (ultrasonography and/or magnetic resonance) and blood tests to detect the presence of non-specific muscle markers. This study was undertaken to evaluate injury to fast and slow-twitch fibres using specific muscle markers for these fibres.

Methods:

Blood samples were obtained from 51 non-sports people and 38 sportsmen with skeletal muscle injury. Western blood analysis was performed to determine fast and slow myosin and creatine kinase (CK) levels. Skeletal muscle damage was diagnosed by physical examination, ultrasonography and magnetic resonance and biochemical markers.

Results:

The imaging tests were found to be excellent for detecting and confirming grade II and III lesions. However, grade I lesions were often unconfirmed by these techniques. Grade I lesions have higher levels of fast myosin than slow myosin with a very small increase in CK levels. Grade II and III lesions have high values of both fast and slow myosin.

Conclusions:

The evaluation of fast and slow myosin in the blood 48 h after the lesion occurs is a useful aid for the detection of type I lesions in particular, since fast myosin is an exclusive skeletal muscle marker. The correct diagnosis of grade I lesions can prevent progression of the injury in athletes undergoing continual training sessions and competitions, thus aiding sports physicians in their decision making.

The changes in the energy metabolism of human muscle induced by training

The biochemical effects of training programmes have been studied with a kinetic model of central metabolism, using enzyme activities and metabolite concentrations measured at rest and after 30 s maximum-intensity exercise, collected before and after long and short periods of training, which differed only by the duration of the rest intervals. After short periods of training the glycolytic flux at rest was three times higher than it had been before training, whereas during exercise the flux and energy consumption remained the same as before training. Long periods of training had less effect on the glycolytic flux at rest, but increased it in response to exercise, increasing the contribution of oxidative phosphorylation.

Cell supports of chitosan/hyaluronic acid and chondroitin sulphate systems. Morphology and biological behaviour

Films and sponges of chitosan (CHI), chitosan/hyaluronic acid (CHI-HA) and chitosan/chondroitin sulphate (CHI-CHOS), were prepared by film deposition or lyophilization (sponges), avoiding the formation of interpolyelectrolyte complexes. The biological behaviour of the systems was analysed by studying the cell behaviour using a fibroblast cell line and standard biological MTT and Alamar Blue tests. The morphology of films, sponges and cell seeded samples was analysed by ESEM. The results obtained indicate that all the systems can be considered as good supports for cell adhesion and proliferation, but there is specific activation of the proliferative process in the presence of hyaluronic acid and chondroitin sulphate.

Evidence of a segregation ratio distortion of SMN1 alleles in spinal muscular atrophy

Spinal muscular atrophy (SMA) is an autosomal recessive disorder characterised by degeneration and loss of the motor neurons of the anterior horn of the spinal cord. The absence of SMN1 is determinant to have SMA and parents of SMA patients are regarded as carriers of the disease. We compared the segregation ratio of the mutated allele and the wild-type allele of all the confirmed carrier parents assuming Mendelian proportions. Results of transmissions in 235 prenatal tests and in 128 unaffected siblings showed a statistically significant deviation in favour of the wild-type SMN1 allele. The number of affected foetuses and carriers were lower than that expected. No significant differences in the sex ratio or in the progenitor origin of the transmitted allele to the carriers were found. One hypothesis that has been advanced to account for the distortion observed in affected foetuses is the negative postzygote selection due to early miscarriage. However, given that the number of carriers in our series was lower than expected, prezygote events such as meiotic drive, survival of gametes or preferential fertilisation should also be considered.

Development of wollastonite-poly(ethylmethacrylate co-vinylpyrrolidone) based materials for multifunctional devices

The manufacturing of a composite made of a synthetic bioactive ceramic, pseudowollastonite (psW), and a bioresorbable copolymer ethylmethacrylate-vinylpyrrolidone (EMA/VP) is presented in this article. psW porous blocks were produced by dipping an open porous polyurethane foam in a psW containing slurry. A 40/60 wt % EMA/VP monomers mixture was poured on the blocks, and free radical polymerization initiated by azobis(isobutyronitrile) at 50 degrees C. Disks of 1 mm height were obtained by cutting the composite with a diamond saw, and bioresorption and bioactivity of the specimens were tested by immersion of the disks into SBF. A ceramic/polymer weight ratio of 72/28, greater than the usually achievable ratio by polymeric solidification of slurries of monomers charged with a powdered solid component, has been obtained. The system is bioactive and does not change the pH of the medium during the degradation test.

Prenatal diagnosis in myotonic dystrophy type 1. Thirteen years of experience: implications for reproductive counselling in DM1 families

OBJECTIVES

To analyse the results obtained from prenatal diagnoses in myotonic dystrophy type 1 (DM1) performed in our hospitals during the last 13 years.

METHODS

Molecular analyses were conducted on chorionic villi or cultured amniotic fluid samples obtained for prenatal diagnosis of DM1. CTG expansion was analyzed by polymerase chain reaction (PCR) and Southern blot techniques.

RESULTS

From 154 prenatal diagnoses performed in 13 years, 51% were found to be healthy and 49% affected. Considering the 75 carriers of the mutation, in 65.3% of the cases, the mother was the transmitting parent versus 36.5% of fathers. From these female transmissions, 31/49 foetuses had expansion in the neonatal form range, namely, congenital myotonic dystrophy (CMD).

CONCLUSIONS

In our series, no significant deviation of the 50% expected frequency of transmission in autosomal dominant disorder was seen. We show that when the disease is transmitted by a male, the mean intergenerational variation is minimal (mean = 56 CTG, SD = 177 CTG). However, this does not occur in the affected mothers, where the mean intergenerational expansion is very high (mean = 948 CTG, SD = 815 CTG) and the difference is statistically significant (t-Student p < 0.0001). Our data have important implications for the genetic counselling of DM1 families.