Central motor deficits of the deltoid muscle in patients with chronic rotator cuff tears.

PURPOSE OF THE STUDY: Previous surface EMG studies have shown that chronic rotator cuff tears (RCT) may be associated with a altered activation of adjacent shoulder muscles. The effect of RCT on central neuromuscular control mechanisms of the shoulder girdle muscles such as the deltoideus muscle (MD), a key muscle of shoulder function, has as yet not been studied in detail. This study investigated the cortico-spinal excitability of the MD to assess the effects of RCT on the central neuromuscular function of upper limb muscles. MATERIAL AND METHODS: The motor evoked potentials (MEP) in response to transcranial magnetic stimulation of MD and first dorsal interosseus muscle (FDI) on both sides were obtained of six right-handed men with chronic, symptomatic, full-thickness RCT on the dominant sides. Stimulus response curves at four different levels were measured at two tasks (MD at rest and during activity). RESULTS: Different interactions were found between stimulus intensity, task and side for MEP of the MD (F = 3.9, P = 0.03), indicating that MD excitability on the affected side were lower when compared with the non-affected side. No correlation was found between the correspondent MEP amplitudes of MD and FDI at rest (r = 0.1, P = 0.44) and MD activation (r = 0.3, P = 0.05) on the affected side whereas a correlation existed on the non-affected side at rest (r = 0.5, P = 0.007) and during activation (r = 0.8, P < 0.001). CONCLUSIONS: These decreased cortico-motoneuronal excitability of the MD on the affected side seems to related to adaptive chan- ges in motor cortex as a consequence of chronic RCT. The data suggest an involvement of central mechanisms and seem to precede severe changes of osteoarthritis of the shoulder.

Anti-donor antibody class switching after liver transplantation.

The humoral immune response directed against donor antigens was monitored by flow cytometry in 17 liver transplant patients using donor leukocytes as targets. Overall, donor-specific antibodies developed in 15 patients; these included all 9 patients who had experienced a biopsy-proven episode of acute rejection and 6 out of 8 patients who had not had an acute episode of rejection. The isotypes of the donor-specific antibodies in the 9 patients who had experienced an early episode of acute rejection were IgG in 8 patients, IgE in 8 patients, and IgA in 6 patients; all 9 patients had IgE and/or IgA antibodies. In the 6 patients who showed no evidence of acute clinical rejection but nevertheless developed donor-specific antibodies, the isotype was IgM associated in 5 of them, with an immunoglobulin class switching to the IgG isotype; none of these patients had antibodies of the IgA or IgE isotype. These results indicate that the lack of rejection of a liver allograft does not necessarily result from a lack of immune response against donor antigens. Rather, the distinct pattern of (cytokine dependent) immunoglobulin class switching suggests that the lack of liver graft rejection may be the result of an immune activation pathway distinct from that resulting in graft rejection.

New mutations causing the premature termination of translation in the A subunit gene of coagulation factor XIII.

The amplification of factor XIII A subunit gene exons and heteroduplex analysis has been used to identify two new mutations that cause severe factor XIII deficiency. One mutation in a family of French origin results from a 4 bp deletion and leads to a premature termination of translation. The other mutation occurred in a Turkish family and results from a C-->T transition that inserts a premature translation stop signal at codon 400. Both mutations alter restriction enzyme sites and can be readily detected in amplified exon DNA for genetic counselling or prenatal diagnosis. The new mutations reflect the extensive molecular heterogeneity of factor XIII deficiency.

[Transabdominal ultrasonography in the diagnosis of lumbar disc herniation]. / Die transabdominale Sonographie in der Diagnostik des lumbalen Bandscheibenprolaps.

AIM: The aim of our study was to assess the value of transabdominal ultrasonography in the diagnosis of a lumbar herniated disc and to investigate the influence of the quality of the ultrasonography investigation on detection of pathological changes in lumbar intervertebral disc. METHOD: 119 patients (55 female, 64 male, mean age 41 years) were included in our study. Patients were suffering from lower back pain and were investigated by transabdominal ultrasonography, using a 3.5 MHz scanner. The results of the ultrasonography investigation were compared with MRI and intraoperative findings RESULTS: The quality of the ultrasonography documentation shows distinct differences between the segments of the lower lumbar spine (L3/4 86.6 %, L4/5 85.7 %, L5/S1 70.6 %). The sonographic evaluations were correct in 75.4 % of cases. Sensitivity of ultrasonography for the detection of an intradiscal lesion was 0.46 for L3/4, 0.83 for L4/5 and 0.78 for L5/S1. Specificity was 0.91 for L3/4, 0.65 for L4/5 and 0.67 for L5/S1. CONCLUSION: Compared to MRI investigation transabdominal ultrasonography of the lumbar herniated disc proved to be distinctly inferior because of methodical limitations and lower diagnostic accuracy. This method, however, can be used as a preliminary diagnostic procedure.

[Gait anlysis in patients with osteoarthritis of the knee before and after total knee replacement]. / Ganganalyse bei Varusgonarthrosepatienten vor und nach unilateraler Knieendoprothesenimplantation.

AIM: The reduction in quadriceps femoris muscle activation is considered to be one of the major mechanisms involved in pathological motion patterns in patients with osteoarthritis (OA) of the knee. These activation deficits are, at least in part, reversible after total knee arthroplasty (TKA). The purpose of this study was to investigate the effects of TKA on motion patterns in patients with OA of the knee. METHOD: 50 patients with knee OA were investigated prior and at 33 +/- 8 months after unilateral TKA. The control group comprised 17 healthy volunteers matched to the study group with respect to age. The gait analysis was performed with an optoelectronic motion analysis system (Elite(R), Italian). RESULTS: Step length, step duration and velocity increased after surgery (p < 0.05), but remained lower than the values of the controls (p < 0.05). Extension angles in stand and swing phase remained unchanged and significantly lower when compared to control values (p = 0.01, p = 0.04). Flexion angles in swing (p = 0.02) and stand phase (p = 0.01) increased on the operated side and were significantly higher than the flexion angle in the control group (p = 0.02, p = 0.03). Reextension in stand phase, which was investigated for quantification of functional range of motion, increased bilaterally after surgery (p < 0.01), but remained lower than the reextension of the controls (p

Analysis of crossover type in the alpha -3.7 haplotype among sickle cell anemia patients from various parts of Africa.

The frequency of alpha+-thalassemia has been determined in African populations carrying beta S-chromosomes of different origins. All these alpha+ thalassemias result from a right-ward deletion. Restriction mapping of the alpha -3.7/haplotype with the enzyme ApaI only showed the presence of a type I crossover. RsaI polymorphism at the 5' end of Z alpha 2 is largely represented in the normal population (gene frequency 23%) but, in our series, never associated with the alpha -3.7/haplotype.

Haemoglobin disorders among Southeast-Asian refugees in France.

Haemoglobin disorders were studied among Southeast-Asian refugees (Vietnamese, Cambodians and Laotians). Phenotypic haemoglobin investigations and genotypical studies concerning the alpha loci were carried out. Most of the observed cases of microcytosis were related to a thalassaemic defect. High prevalence of Hb E and alpha-thalassaemia were found.