Decreased expression of DMPK: correlation with CTG repeat expansion and fibre type composition in myotonic dystrophy type 1

Abstract Myotonic dystrophy type 1 (DM1) is an autosomal dominant disease caused by a trinucleotide repeatexpansion, cytosine-thymine-guanine (CTG)_n, in the 3′ untranslated region of a gene encoding the myotonic dystrophy protein kinase (DMPK). To correlate CTG expansion and protein expression, we studied muscle specimens from 16 adult DM1 patients using three anti-DMPK antibodies for immunoblotting. We estimated the amount of the full-length DMPK (85 kDa) in muscle biopsies from normal controls and from DM1 patients carrying different (CTG)_n expansions. We found that DMPK concentration was decreased to about 50% in DM patients’ muscles; the protein decrease did not seem correlated with the CTG repeat length. However, the fibre type composition in skeletal muscle seemed somehow to affect DMPK decrease, as the lowest level of the enzyme was found in patients with the lowest content of type 1 fibre.     

Usefulness of gallium 67 in research into the need for radical cervical lymph node dissection in patients with head and neck carcinomas

Fifty-nine patients with head and neck carcinoma were examined with 67Ga scintigraphy. All patients had undergone lymph node dissection of the neck. They were followed for a minimum of 2 years after the examination. The primary tumor, treated prior/contemporaneously to the lymph node dissection, did not evolve in this interval. Metastatic involvement of the lymph node capsule was observed in all 44 cases with metastatic lymph nodes; macroscopic radicality was surgically obtained since involvement of the capsule was only microscopic. Nevertheless, complementary radiotherapy was given. The whole of 17 recurrences in the soft tissues of the neck were found, within 2 years, in the group of 26 patients who had undergone dissection of lymph nodes with metastatic capsular involvement and whose postoperative 67Ga scintigraphy was positive. On the contrary, no recurrences in the soft tissues of the neck were observed in the group of 18 patients who had undergone dissection of lymph nodes with metastatic capsular involvement and whose scintigraphy was negative. This result proves (P less than 0.001) 67Ga capable of evidencing eventual microscopic diffusion. Such a possibility has not yet been realized in vivo with any other investigation technique. Scintigraphy was negative in a control group of 15 patients who had undergone lymph node dissection, and with nonmetastatic lymph nodes. This finding leads us to exclude that the use of 67Ga might result in misinterpreted findings in the exploration of relatively superficial tissues. In fact, the eventual accumulation of radioisotope in nonneoplastic pathologies is quite easily recognizable in the neck. We can therefore conclude that in those 9 cases with positive scintigraphy and in whom no recurrence was found, microscopic diffusion was probably present, but local recurrence of the disease was prevented by complementary radiotherapy.     

Stability of skeletal Class III malocclusion after combined maxillary and mandibular procedures: titanium versus resorbable plates and screws for maxillary fixation.

PURPOSE: The aim of this study was to evaluate skeletal stability after double jaw surgery for correction of skeletal Class III malocclusion to assess if there were any differences between resorbable plate and screws and titanium rigid fixation of the maxilla. PATIENTS AND METHODS: Twenty-two Class III patients had bilateral sagittal split osteotomy for mandibular setback stabilized with rigid internal fixation. Low level Le Fort I osteotomy for maxillary advancement was stabilized with conventional titanium plate and screws in 12 patients (group 1) and with resorbable plate and screws in 10 patients (group 2). Lateral cephalograms were taken before surgery, immediately postoperatively, 8 weeks after surgery, and 1 year postoperatively. RESULTS: Before surgery both groups were balanced with respect to linear and angular measurements of craniofacial morphology. One year after surgery, maxillary stability was excellent in both groups. In group 1 no significant correlations were found between maxillary advancement and relapse. In group 2, significant correlations were found between maxillary advancement and relapse at A point and posterior nasal spine. No significant differences in postoperative skeletal and dental stability between groups were observed. CONCLUSION: Surgical correction of Class III malocclusion after combined maxillary and mandibular procedures appears to be a fairly stable procedure for maxillary advancements up to 5 mm independently from the type of fixation used to stabilize the maxilla. Resorbable devices should be used with caution for bony movements of greater magnitude until their usefulness is evaluated in studies with large maxillary advancements.     

Association of myopathy with large-scale mitochondrial dna duplications and deletions: Which is pathogenic?

We identified large-scale heteroplasmic mitochondrial DNA (mtDNA) rearrangements in a 50–year-old woman with an adult-onset progressive myopathy. The predominant mtDNA abnormality was a 21.2–kb duplicated molecule. In addition, a small population of the corresponding partially deleted 4.6–kb molecule was detected. Skeletal muscle histology revealed fibers that were negative for cytochrome c oxidase (COX) activity and had reduced mtDNA-encoded COX subunits. By single-fiber polymerase chain reaction analysis, COX-negative fibers contained a low number of wild-type or duplicated mtDNA molecules (ie, nondeleted). In situ hybridization demonstrated that the abnormal fibers contained increased amounts of mtDNA compared with normal fibers and that most of the genomes were deleted. We concluded that deleted mtDNA molecules were primarily responsible for the phenotype in this patient.     

Adoptive immunotherapy of feline immunodeficiency virus with autologous ex vivo-stimulated lymphoid cells modulates virus and T-cell subsets in blood

The potential of immunotherapy with autologous virus-specific T cells to affect the course of feline immunodeficiency virus (FIV) infection was explored in a group of specific-pathogen-free cats infected with FIV a minimum of 10 months earlier. Popliteal lymph node cells were stimulated by cocultivation with UV-inactivated autologous fibroblasts infected with recombinant vaccinia viruses expressing either FIV gag or env gene products, followed by expansion in interleukin-2. One or two infusions of both Gag- and Env-stimulated cells resulted in a slow increase in FIV-specific gamma interferon-secreting T cells in the circulation of cats. In the same animals, viral set points fluctuated widely during the first 2 to 3 weeks after adoptive transfer and then returned to pretreatment levels. The preexisting viral quasispecies was also found to be modulated, whereas no novel viral variants were detected. Circulating CD4(+) counts underwent a dramatic decline early after treatment. CD4/CD8 ratios remained instead essentially unchanged and eventually improved in some animals. In contrast, a single infusion of Gag-stimulated cells alone produced no apparent modulations of infection.     

Colour Doppler changes and thromboxane production after ovarian stimulation with gonadotrophin-releasing hormone agonist

The objective of this study was to evaluate the Doppler flow variations which occur following the use of different protocols of ovarian stimulation in an IVF programme, and to investigate the thromboxane production by cultured endometrial cells and its influence on embryo implantation. A total of 60 patients underwent three different ovarian stimulation protocols: long gonadotrophin-releasing hormone agonist (GnRH-a), short GnRH-a and no GnRH-a. Transvaginal ultrasonography and colour Doppler analysis were performed before and during the treatment. On the day that the Doppler examination took place, luteinizing hormone, follicle stimulating hormone, plasma oestradiol and thromboxane concentrations were assayed. On the day of oocyte retrieval, endometrial cells were collected and cultured, and their thromboxane production evaluated. No significant differences in hormonal, ultrasonographic or Doppler parameters were observed between the three groups. Ten out of 56 patients who had a successful embryo transfer became pregnant. In the group of pregnant women the pulsatility index values of both uterine and spiral arteries was lower than in non-pregnant patients, and was associated with significantly lower thromboxane concentrations from cultured endometrial cells. It is concluded that thromboxane plays a role in embryo implantation, and that Doppler flow analysis of uterine and spiral arteries in infertile patients may be important in the management of ovarian stimulation.      

Luminal surface microgeometry affects platelet adhesion in small-diameter synthetic grafts

One of the major problems when using small-diameter vascular grafts in arterial reconstruction is the development of platelet-rich thrombi as a consequence of blood contact with artificial surfaces. The degree of occlusion is certainly affected by the thrombogenicity of the internal surface that seems to play a key role in patency and long-term wound healing of grafts. In this study, the blood compatibility of Cardiothane (CA) vascular grafts was investigated. The CA material, a blend of polyurethane and polydimethylsiloxane that has shown relatively good physical and biocompatibility properties, was manufactured into vascular grafts by the instrument named "spray-machine". Grafts with different luminal surface porosity were produced using increasing CA concentrations by the "spray-machine" and the blood compatibility was evaluated in vitro by a circulation system in which the human blood was allowed to interact with the material in a well-controlled setting. The samples of circulating blood were collected at different times of circulation and platelet adhesion and activation were studied. Grafts with a highly porous luminal surface induced a lower adhesion and activation of platelets in vitro than the low-porosity ones. These results underlined the importance of the microgeometry of the graft luminal surface in the interaction with blood.     

Cloning and characterization of two catechol 1,2-dioxygenase genes from Acinetobacter radioresistens S13

Two novel catechol 1,2-dioxygenase (C 1,2-O) genes have been isolated from an Acinetobacter radioresistens strain that grows on phenol or benzoate as sole carbon and energy source. Designated as catA(A) and catA(B), they encode proteins composed of 314 and 306 amino acids, whose deduced sequences indicate that they have approximately 53% identity, whereas their NH2-terminal and COOH-terminal regions have no sequences in common. This may explain their different thermal and pH stability. Polyclonal antibodies raised against an amino-terminal CatA(A) peptide or the whole CatA(B) protein were used to establish their inducible and differential expression patterns upon bacterial growth in phenol or benzoate. The CatA(A) protein (IsoA) was induced by both phenol and benzoate though with different kinetics, whereas the catA(B) product (IsoB) was constitutively produced at low levels that increased only during growth in the presence of benzoate.     

A trial of intranasal Atrovent versus placebo in the treatment of vasomotor rhinitis

Twenty-six patients with perennial rhinorrhea were treated by Atrovent, the anticholinergic agent, or placebo in a randomized double-blind crossover trial. The severity and duration of rhinorrhea were significantly reduced by Atrovent. Local side effects were more frequent with the active drug. These were reduced in a later open trial by a reduction in dosage.