Isotretinoin treatment of autosomal recessive congenital ichthyosis complicated by coexisting dysferlinopathy.

Consanguinity is known to be associated with an increase in the prevalence of autosomal recessive disorders such as autosomal recessive congenital ichthyosis (ARCI). ARCI often responds well to retinoid treatment. We describe a patient with ARCI who improved under isotretinoin treatment. The patient subsequently developed elevated levels of serum creatinine phosphokinase (CPK), which led to the diagnosis of a second autosomal recessive disorder, dysferlinopathy, a rare myopathy characterized by muscle weakness, decreased tendon reflexes and marked elevation of CPK levels. This report demonstrates the need for physicians to remain alert to the possible coexistence of rare and mutually relevant disorders in populations with a high rate of consanguinity.

The role of therapeutic plasma exchange in pemphigus vulgaris.

BACKGROUND: The treatment of pemphigus, an autoimmune bullous disease, is based on the combination of corticosteroids and adjuvant therapies, such as immunosuppressive drugs, anti-inflammatory drugs and immunomodulatory procedures, such as intravenous immunoglobulin and therapeutic plasma exchange (TPE). OBJECTIVE: This study aims to assess our experience with TPE as a steroid-sparing modality in moderate and severe intractable pemphigus patients. METHODS: A retrospective evaluation for all intractable pemphigus patients treated by TPE in a university-affiliated tertiary referral medical centre between the years 1998 and 2008. Treatment protocol included three TPE treatments weekly for 1-3 months, combined with monthly pulse therapy of dexamethasone and/or cyclophosphamide. Maintenance therapy was based on once/bi weekly TPE treatments or monthly intravenous immunoglobulin. RESULTS: Seven patients were included in the study, four with severe pemphigus vulgaris and three with moderate disease. Six of the seven patients responded to TPE: Four patients (57%) achieved complete remission and two patients (28%) achieved partial remission on minimal therapy. Mild adverse effects related to TPE were observed in two patients and included dizziness and mild headache. CONCLUSION: TPE is a well-tolerated effective steroid-sparing agent in recalcitrant pemphigus patients.

Silicone breast implant rupture presenting as bilateral leg nodules.

Gross migration of silicone gel from ruptured breast implants is a rare event. It is associated with extravasation of gel into the breast parenchyma, and to distant locations such as the abdominal wall and inguinal areas. This silicone deposits present as subcutaneous nodules and cause a local reaction known as siliconoma. We evaluated a 56-year-old woman who presented with a 2-year history of painful, firm and ill-defined subcutaneous nodules on the medial aspect of the shins and ankles. Her medical history was notable for bilateral breast augmentation with silicone implants 30 years before presentation. Although there were no signs or symptoms on breast examination, ultrasonography and magnetic resonance imaging confirmed that both implants had ruptured. Histological examination of a punch biopsy from a nodule on the shin found lobular granulomatous panniculitis. An excisional biopsy of the lesion was analysed by scanning electron microscopy and was found to contain silicone. This is a rare case of gross migration of silicone to the shins, originating from ruptured breast implants. To our knowledge, there is no previous report of silicone migration to such a distant location. We discuss the common presentation of silicone migration and highlight the importance of awareness among dermatologists and plastic surgeons about this unusual occurrence.

Pancreatic panniculitis and carcinoma of the pancreas.

Pancreatic panniculitis is a rare complication of carcinoma of the pancreas, most often accompanying the rare acinar cystadenocarcinoma. It presents with painful erythematous subcutaneous nodules typically located on the leg. We present a case of a 79-year-old man with neuroendocrine carcinoma of the pancreas and liver metastasis, who developed painful subcutaneous nodules on his shins. Laboratory values included a raised lipase level with normal amylase level and peripheral eosinophilia. The patient was treated with nonsteroidal anti-inflammatory drugs, dexamethasone and antibiotics, with resolution of the dermatological symptoms.

Low variability of internal transcribed spacer rDNA and trnL (UAA) intron sequences of several taxa in the Festuca ovina aggregate (POACEAE).

Identification and classification of numerous Festuca species is still a difficult problem due to the close morphological resemblance. The most difficult fine fescues to identify belong to the Festuca ovina aggregate, which is the largest group in the genus Festuca. Many taxons are considered to be separate species based on quantitative taxonomic characters, differences in ploidy level or the structure of sclerenchyma cells. In order to evaluate the taxonomic value of DNA-based markers, sequence analysis of the internal transcribed spacer (ITS1-5.8S-ITS2) region and the chloroplast trnL (UAA) intron was performed in the ten most problematic fine fescues belonging to the Festuca ovina aggregate. Intraspecific ITS variants were found in a single case while in other cases only intragenomic ITS polymorphisms were detected with 1-2 ambiguous positions. Among the sequences of the trnL (UAA) intron even intragenomic polymorphisms were not detected in any of the Festuca species studied. Thus, the results do not support the species status of these ten taxa.

Localisation of merosin-positive congenital muscular dystrophy to chromosome 4p16.3.

The congenital muscular dystrophies (CMD) are a heterogeneous group of autosomal recessive disorders, which present within the first 6 months of life with hypotonia, muscle weakness and contractures, associated with dystrophic changes on skeletal muscle biopsy. We have previously reported a large consanguineous family segregating merosin-positive congenital muscular dystrophy, in which involvement of known CMD loci was excluded. A genome-wide linkage search of the family conducted using microsatellite markers spaced at 10-Mb intervals failed to identify a disease locus. A second scan using a high-density SNP array, however, permitted a novel CMD locus on 4p16.3 to be identified (multipoint LOD score 3.4). Four additional consanguineous CMD families with a similar phenotype were evaluated for linkage to a 4.14-Mb interval on 4p16.3; however, none showed any evidence of linkage to the region. Our findings further illustrate the utility of highly informative SNP arrays compared with standard panels of microsatellite markers for the mapping of recessive disease loci.

Gene content and density in banana ( Musa acuminata) as revealed by genomic sequencing of BAC clones.

The complete sequence of Musa acuminata bacterial artificial chromosome (BAC) clones is presented and, consequently, the first analysis of the banana genome organization. One clone (MuH9) is 82,723 bp long with an overall G+C content of 38.2%. Twelve putative protein-coding sequences were identified, representing a gene density of one per 6.9 kb, which is slightly less than that previously reported for Arabidopsis but similar to rice. One coding sequence was identified as a partial M. acuminata malate synthase, while the remaining sequences showed a similarity to predicted or hypothetical proteins identified in genome sequence data. A second BAC clone (MuG9) is 73,268 bp long with an overall G+C content of 38.5%. Only seven putative coding regions were discovered, representing a gene density of only one gene per 10.5 kb, which is strikingly lower than that of the first BAC. One coding sequence showed significant homology to the soybean ribonucleotide reductase (large subunit). A transition point between coding regions and repeated sequences was found at approximately 45 kb, separating the coding upstream BAC end from its downstream end that mainly contained transposon-like sequences and regions similar to known repetitive sequences of M. acuminata. This gene organization resembles Gramineae genome sequences, where genes are clustered in gene-rich regions separated by gene-poor DNA containing abundant transposons.

Promoters for pregenomic RNA of banana streak badnavirus are active for transgene expression in monocot and dicot plants.

Two putative promoters from Australian banana streak badnavirus (BSV) isolates were analysed for activity in different plant species. In transient expression systems the My (2105 bp) and Cv (1322 bp) fragments were both shown to have promoter activity in a wide range of plant species including monocots (maize, barley, banana, millet, wheat, sorghum), dicots (tobacco, canola, sunflower, Nicotiana benthamiana, tipu tree), gymnosperm (Pinus radiata) and fern (Nephrolepis cordifolia). Evaluation of the My and Cv promoters in transgenic sugarcane, banana and tobacco plants demonstrated that these promoters could drive high-level expression of either the green fluorescent protein (GFP) or the beta-glucuronidase (GUS) reporter gene (uidA) in vegetative plant cells. In transgenic sugarcane plants harbouring the Cv promoter, GFP expression levels were comparable or higher (up to 1.06% of total soluble leaf protein as GFP) than those of plants containing the maize ubiquitin promoter (up to 0.34% of total soluble leaf protein). GUS activities in transgenic in vitro-grown banana plants containing the My promoter were up to seven-fold stronger in leaf tissue and up to four-fold stronger in root and corm tissue than in plants harbouring the maize ubiquitin promoter. The Cv promoter showed activities that were similar to the maize ubiquitin promoter in in vitro-grown banana plants, but was significantly reduced in larger glasshouse-grown plants. In transgenic in vitro-grown tobacco plants, the My promoter reached activities close to those of the 35S promoter of cauliflower mosaic virus (CaMV), while the Cv promoter was about half as active as the CaMV 35S promoter. The BSV promoters for pregenomic RNA represent useful tools for the high-level expression of foreign genes in transgenic monocots.

A promoter from sugarcane bacilliform badnavirus drives transgene expression in banana and other monocot and dicot plants.

A 1369 bp DNA fragment (Sc) was isolated from a full-length clone of sugarcane bacilliform badnavirus (ScBV) and was shown to have promoter activity in transient expression assays using monocot (banana, maize, millet and sorghum) and dicot plant species (tobacco, sunflower, canola and Nicotiana benthamiana). This promoter was also tested for stable expression in transgenic banana and tobacco plants. These experiments showed that this promoter could drive high-level expression of the beta-glucuronidase (GUS) reporter gene in most plant cells. The expression level was comparable to the maize ubiquitin promoter in standardised transient assays in maize. In transgenic banana plants the expression levels were variable for different transgenic lines but was generally comparable with the activities of both the maize ubiquitin promoter and the enhanced cauliflower mosaic virus (CaMV) 35S promoter. The Sc promoter appears to express in a near-constitutive manner in transgenic banana and tobacco plants. The promoter from sugarcane bacilliform virus represents a useful tool for the high-level expression of foreign genes in both monocot and dicot transgenic plants that could be used similarly to the CaMV 35S or maize polyubiquitin promoter.

Genetic transformation of banana and plantain (Musa spp.) via particle bombardment.

We have developed a simple protocol to allow the production of transgenic banana plants. Foreign genes were delivered into embryogenic suspension cells using accelerated particles coated with DNA. Bombardment parameters were optimized for a modified particle gun resulting in high levels of transient expression of the beta-glucuronidase gene in both banana and plantain cells. Bombarded banana cells were selected with hygromycin and regenerated into plants. Molecular and histochemical characterization of transformants revealed the stable integration of the transferred genes into the banana genome.

Locus-specific primers for LMW glutenin genes on each of the group 1 chromosomes of hexaploid wheat.

To reveal the chromosomal location of three known low-molecular-weight (LMW) glutenin genes in wheat, we designed and used three sets of sequence-specific primers in polymerase chain reactions (PCR) on 'Chinese Spring' and its derived group 1 aneuploid nullisomic-tetrasomic stocks. Two sets proved to be chromosome specific and amplified sequences from the Glu-A3 and Glu-D3 loci, respectively. The third set was apparently composed of conserved sequences as it produced PCR products in each of the aneuploids. Two of these products were cloned, and their sequences differed from the known LMW glutenin genes at several positions. Again, primer sets specific for these sequences were designed. One set was directed to the Glu-A3 locus, the second set resulted in two PCR products differing in length, one of which was located on chromosome 1B and the other on 1D. Primer sets constructed for the latter two sequences were specific for the Glu-B3 and Glu-D3 loci, respectively. Hence, primer sets specific for each of the three homoeologous chromosomes of the group 1 (1A, 1B, 1D) are available. In addition, these locus-specific primers were assayed for their ability to distinguish among wheat cultivars. PCR products amplified with one of the Glu-A3-specific primer sets showed length polymorphisms in various wheat varieties. Varieties carrying the 1RS.1BL translocated chromosomes could be recognized by the absence of a PCR product when the Glu-B3 primer set was used. These results suggest that PCR with locus-specific primers can be useful in the molecular genetic analysis of hexaploid wheat.

Transient gene expression in electroporated banana (Musa spp., cv. 'Bluggoe', ABB group) protoplasts isolated from regenerable embryogenetic cell suspensions.

Electroporation conditions were established for transient expression of introduced DNA in banana (Musa spp., cv. 'Bluggoe') protoplasts isolated from regenerable embryogenic cell suspensions. The following parameters were found to be highly influential: electroporation buffer, polyethylene glycol treatment and its duration before electroporation, use of a heat shock, and chimaeric gene constructs. The maximum frequency of DNA introduction as detected by an in situ assay for transient expression of the uidA gene, amounted to 1.8% of total protoplasts. Since plants have recently been regenerated from banana protoplasts at a high frequency, the present results may contribute to the production of transgenic banana.

Evidence for cytoplasmic control of in vitro microspore embryogenesis in the anther culture of wheat (Triticum aestivum L.).

Anthers were cultured from two sets of seven lines of hexaploid wheat (Triticum aestivum L.) with different cytoplasms, the euplasmic nucleus donors, 'Siete Cerros 66' and 'Penjamo 62', as well as their six alloplasmic lines derived from wild relative species of the genera Triticum and Aegilops. Significant cytoplasmic and nuclear effects but no cytoplasmic-nuclear interaction were found for embryogenic anther response, with the best performance of 'Penjamo 62' in Ae. kotschyi cytoplasm. Plant regeneration was not affected significantly by the cytoplasmic background of the lines cultured. The possible genetic implications of the observed cytoplasmic and nuclear influences on the in vitro haploid induction of wheat are discussed.