[A successful treatment for myonephropathic metabolic syndrome after operation of acute aortic dissection (Stanford type A) with multiple organ ischemia]

A 60-year-old man had sudden chest pain and right lower extremity pain. A diagnosis of acute aortic dissection (Stanford type A) with right lower extremity ischemia was made. An emergency ascending aortic and total arch replacement, right axillo-femoral bypass, and coronary artery bypass grafting was performed for acute aortic dissection, acute right iliac arterial occlusion, and acute myocardial infarction. Myonephropathic metabolic syndrome (MNMS) occurred 2 days after operation. The serum creatine kinase value increased over 68,000 U/l, hemodiafiltration was started on the 2nd postoperative day (POD). The patient fell into anuric state and hemodiafiltration was performed 3 times a week. Urination was obtained over 1,000 ml/day from the 25th POD and hemodiafiltration was not necessary any more. We emphasize that prompt operation including revascularization of ischemic leg should be performed in acute aortic dissection with extremity ischemia and also prompt hemodiafiltration to improve the prognosis of these disastrous lesion.

Interference effects in the resonant photoemission channels to the Ne+ 2p(4)(1D2)3p 2P, 2D, and 2F states in the Ne 1s excitation region

We present measurements of total and partial photoionization cross sections of Ne in the 1s excitation region. The total cross section exhibits resonances with symmetric profiles, whereas the branching ratios to the Ne+ 2p(4)(1D2)3p 2P, 2D, and 2F states present strong oscillations in the interresonance regions. We prove that not only the interference between the direct and resonant ionization processes but also the interference among the ionization processes via different nonisolated resonances are important for this effect.

Anthropometry of the proximal tibia to design a total knee prosthesis for the Japanese population

Anthropometric data on proximal tibiae of 100 knees in 80 Japanese patients undergoing total knee arthroplasty were obtained. Anterior-posterior (AP) and medial-lateral (ML) lengths of the tibia were measured on computed tomography scans and intraoperatively on tibial resection surfaces. A special small component is unnecessary, and size variation should focus on ML length of 65 to 75 mm because this includes 90% of women's knees. AP-to-ML ratio had a negative correlation with ML length, indicating that small knees were longer in the AP direction. Most prostheses had AP mismatch up to 5 mm for small women's knees. These data could provide the basis for designing the optimal tibial component for most of the Asian-Pacific population.

[Dor operation combined with redo coronary artery bypass grafting; report of two successful cases]

Case 1. A 69-year-old male, who had undergone coronary artery bypass grafting with saphenous vein graft for acute myocardial infarction 16 years previously, was admitted into our hospital for heart failure and recurrent angina. Coronary angiography showed occlusion of the graft and 75% stenosis in the proximal circumflex artery. Left ventriculography showed end-diastolic volume of 216 ml and ejection fraction of 24%. Dor operation combined with redo coronary artery bypass grafting was performed. Postoperatively, the ejection fraction improved to 53% and the cardiac index improved from 1.8 to 2.2 l/min/m2. Case 2. A 67-year-old male, who had undergone double coronary artery bypass grafting using saphenous vein grafts for acute myocardial infarction 8 years previously, was admitted into our hospital for heart failure and recurrent angina. Coronary angiography showed occlusion of the 2 grafts and 99% stenosis of the proximal left anterior descending artery. Although the left ventricle was slightly dilated, echocardiography demonstrated a thrombus in the left ventricle. Dor operation was performed concomitantly with removing of the thrombus and redo coronary artery bypass grafting. Postoperatively, the ejection fraction improved to 68% and the cardiac index improved from 1.6 to 2.3 l/min/m2. When the patients underwent coronary artery bypass surgery with saphenous vein grafts for acute myocardial infarction, they could be susceptible to left ventricular asynergy and graft failure on the long run. Therefore, the patients who need redo coronary revascularization may be potential candidates for Dor operation, and they require close examination regarding the myocardial viability, volume and shape of the left ventricle.

Bone anatomy and rotational alignment in total knee arthroplasty

The purpose of the current study was to investigate the bone anatomy in determining the rotational alignment in total knee arthroplasty using computed tomography. Axial images of 109 knees in 83 patients with varus osteoarthritis who had total knee arthroplasty were analyzed. On the images of the distal femur and the proximal tibia, a baseline for the anteroposterior axis of each component was drawn based on the epicondylar axis for the femur and the medial (1/3) of the tibial tuberosity for the tibia. The angle between these two lines was analyzed as the rotational mismatch between the components when they were aligned to the anatomic landmarks of each bone. Fifty-four knees (49.5%) had an angle of 5 degrees or greater and 13 knees (11.9%) had an angle of 10 degrees or greater. There was a tendency to align the tibial component in external rotation relative to the femoral component. The results indicated that the landmarks of each bone were the intrinsic cause of the rotational mismatch in knees with varus osteoarthritis. Surgeons doing total knee arthroplasties should be aware of this and check the rotational mismatch between the components. When it is present, the tibial component should be realigned to match the femoral component rotation to minimize problems caused by the mismatch.

Inhibitory effects of organotin compounds on voltage-dependent, tetrodotoxin-resistant Na+ channel current in guinea pig dorsal root ganglion cells

The effects of organotin compounds on voltage-dependent, tetrodotoxin (TTX)-resistant Na+ channel current (I(Na)) in single cells isolated from guinea pig dorsal root ganglion were investigated using a whole cell patch clamp technique. Extracellular application of tributyltin (TBT) inhibited I(Na) in a concentration-dependent manner with an IC50 of 7.2 microM. TBT (100 microM), when applied intracellularly, was without effect. Triphenyltin (TPT, 100 microM) and dibutyltin (DBT, 100 microM), applied extracellularly, inhibited I(Na) with an efficacy ranking of TBT>TPT>DBT. Monobutyltin (100 microM), whether applied externally or internally, had little effect on I(Na). TBT (30 microM) significantly prolonged both time to peak and half-decay time of I(Na) and shifted the activation curve of I(Na) in the positive direction without changing the slope. No such effect was produced by TPT (100 microM). The results indicate that organotin compounds inhibit voltage-dependent, TTX-resistant Na+ channel activity and suggest that the inhibitory action may account, at least in part, for their neurotoxic effects.

Possibility of "distraction arthrogenesis": first report in rabbit model

We investigated the possibility of articular cartilage distraction for use in reconstructing joint structure and for increasing the donor site of osteochondral grafts. Intraarticular osteotomy was performed at the femoral condyle in 12 Japanese white rabbits. The bone segment was fixed with a specially designed external fixator. After a 3-week waiting period, distraction was performed intermittently for 3 weeks (0.7 mm x 3 times per week) in the distraction group (n = 7) and, in the remaining animals (gap group; n = 5), a gap of 6.3 mm in length was made at surgery. All rabbits received etidronate injections (20 mg/kg x2 times per week) for 5 weeks, to slow mineralization. The femoral condyle was harvested 9 weeks postoperatively and decalcified sagittal sections were stained and evaluated, using a histological grading scale. In the distraction group, distraction of 4.2 +/- 1.4 mm was achieved, and the distracted cartilage area was filled with regenerated cartilage, without any gap between the regenerated and the adjacent articular cartilage. This regenerated cartilage showed metachromasia with toluidine blue. In the gap group, newly formed cartilage tissue was folded from the edge of the osteotomy site and fibrous tissue was interposed in the gap. The histological grading score was significantly lower in the distraction group (P < 0.02). Our preliminary results demonstrated the possibility of cartilage distraction; however, long-term observation will be necessary to confirm the characteristics of the distracted cartilage. We may call the process "distraction arthrogenesis", because the entire articular entity, which consists of cartilage, subchondral bone, and bone, could be distracted at once.

No evidence of PEG1/MEST gene mutations in Silver-Russell syndrome patients

Silver-Russell syndrome (SRS) is characterized by prenatal and postnatal growth retardation with morphologic anomalies. Maternal uniparental disomy 7 has been reported in some SRS patients. PEG1/MEST is an imprinted gene on chromosome 7q32 that is expressed only from the paternal allele and is a candidate gene for SRS. To clarify its biological function and role in SRS, we screened PEG1/MEST abnormalities in 15 SRS patients from various standpoints. In the lymphocytes of SRS patients, no aberrant expression patterns of two splice variants (alpha and beta) of PEG1/MEST were detected when they were compared with normal samples. Direct sequence analysis failed to detect any mutations in the PEG1/MEST alpha coding region, and there were no significant mutations in the 5'-flanking upstream region containing the predicted promoter and the highly conserved human/mouse genomic region. Differential methylation patterns of the CpG island for PEG1/MEST alpha were normally maintained and resulted in the same pattern as in the normal control, suggesting that there was no loss of imprinting. These findings suggest that PEG1/MEST can be excluded as a major determinant of SRS.

Angiographic assessment of surgical reconstructions for left ventricular asynergy with indices of abnormally contracting segments

BACKGROUND

In surgical reconstruction for left ventricular asynergy after myocardial infarction, the conventional linear closure technique second to simple resection and endoventricular circular patch plasty, which is the so-called Dor technique, are commonly utilized. We assessed these techniques using an abnormally contracting segment (ACS) in the left ventriculogram.

METHODS

We reviewed 10 and 15 patients who underwent the linear technique (group L) and the Dor technique (group D), respectively. %ACS was determined as the percent ratio of both akinetic and dyskinetic chords among the total chords in the centerline method of regional wall motion analysis. A difference between preoperative and postoperative ejection fraction (EF) was generated by preoperative EF and this percentage ratio was determined as %EF.

RESULTS

Postoperative EF improved from 31% to 41% in group L and from 33% to 49% in group D (p<0.05). Postoperative EF in group D was higher than in group L (p<0.05). %ACS decreased from 41% to 34% in group L and from 41% to 19% in group D (p<0.05). Postoperative %ACS was lower in group D than in group L (p<0.05). The significant correlation between preoperative %ACS and %EF was negative in group L and positive in group D (p<0.05).

CONCLUSIONS

The Dor technique is more effective for the postoperative systolic function than the linear technique because more extensive reduction in %ACS is possible with the Dor technique than with the linear technique. Dor technique becomes more crucial to the postoperative systolic function as the preoperative %ACS becomes larger.

[On the usages of I'm there]

An English place adverb there basically does not refer to a place which belongs to the speaker's territory at the time of utterance. However, there is an expression, I'm there, which appears to violate this condition. I examine the usages of this expression as well as related expressions, which include a case where there indirectly identifies a place where the speaker is at the time of utterance, a case where it metaphorically refers to a "state", and an idiomatic usage meaning, "I will definitely go there."

Novel mutation in exon 18 of the cartilage oligomeric matrix protein gene causes a severe pseudoachondroplasia

Pseudoachondroplasia (PSACH) is a common skeletal dysplasia characterized by disproportionate short stature, early-onset osteoarthrosis, and dysplasia of the spine, epiphysis, and metaphysis. Multiple epiphyseal dysplasia (MED) is a similar but less severe disorder characterized by dysplasia of the epiphysis. Both disorders are caused by mutations in the cartilage oligomeric matrix protein (COMP) gene. COMP mutations cluster in a region of the gene that encodes calmodulin-like repeats (CLRs) and correlate closely with disease severity. Typically, mutations in exon 13 that composes the seventh CLR produce severe PSACH phenotypes, whereas mutations found elsewhere in the gene produce mild PSACH or MED phenotypes. We have identified a PSACH patient carrying a novel mutation in exon 18 of COMP that composes the C-terminal globular domain. This mutation produced a severe PSACH phenotype with marked short stature and deformities of the spine and extremities. Our results extend the range of disease-causing mutations within the COMP gene and demonstrate the importance of the additional domain of COMP protein in its in vivo function.

Female gonadal development in XX patients with distal 9p monosomy

OBJECTIVE

A sex determining gene(s) has been mapped to a approximately 700 kb region distal to the exons of DMRT1 on 9p. The aim of this study was to examine gonadal developmental status in XX patients hemizygous for the 9p sex determining region.

DESIGN

Clinical and molecular studies were performed in an 8-year-old girl with 46,XX,del(9)(p22) (case 1) and in a 2-year-old girl with 46,XX,del(9)(p23) (case 2).

METHODS

Ovarian function status was assessed by gonadotrophin-releasing hormone (GnRH) tests. Hemizygosity for the sex determining region was examined by fluorescence in situ hybridisation and microsatellite analyses for a total of 17 loci on distal 9p.

RESULTS

GnRH tests indicated mild gonadotrophin hyper responses in both cases (case 1: follicle stimulating hormone 9.2-->22.7 IU/l, luteinising hormone 0.7 --> 16.6 IU/l; case 2: follicle stimulating hormone 7.6 --> 38.2 IU/l, luteinising hormone 0.6 --> 9.4 IU/l). Molecular studies showed hemizygosity for the 9p sex determining region in both cases.

CONCLUSIONS

The results, in conjunction with previous reports describing sex development in XX and XY patients hemizygous for the 9p sex determining region, imply that haploinsufficiency of the 9p sex determining gene(s) primarily hinders the formation of the indifferent gonad, leading to a wide range of testicular or ovarian development.

New lattice-Boltzmann model for magnetic fluids

A new type of two-dimensional lattice-Boltzmann model is developed in order to study the rheological properties of magnetic fluids. The appropriate extension of the lattice-Boltzmann scheme for magnetohydrodynamics makes it possible to deal with the rotation of the magnetic moment without losing the advantage of its simple algorithm. This model is suitable for simulating various behaviors of magnetic fluids influenced by the internal angular momentum.