Total hip arthroplasty using hydroxyapatite-coated cementless cup for rapidly destructive coxarthrosis: Minimum 10-year follow-up

BackgroundPerforming total hip arthroplasty (THA) as early as possible is recommended for rapidly destructive coxarthrosis (RDC) as it causes pain that becomes progressively more severe. However, acetabular bone loss remains an issue in THA. Special devices, such as a Kerboull-type plate, may be used for acetabular bone defects, but the procedure is highly invasive and often the patients are elderly, further complicating matters. We retrospectively investigated the clinical and radiographic results of THA using conventional hydroxyapatite-coated cementless cup in RDC.MethodsA total of 32 patients (35 hips) with RDC were enrolled in the study with a minimum 10-year follow-up. All THAs were performed using conventional hydroxyapatite-coated cementless cup. All patients were evaluated clinically according to the Harris hip score (HHS). Acetabular bone deficiency was classified according to the American Academy of Orthopaedic Surgeons (AAOS) classification.ResultsEleven hips (31%) were AAOS type III, and none were type IV. Total HHS significantly improved from 36.5 to 79.4 (p < 0.01). Two cups exhibited loosening. The overall implant-associated survival rate after 10 years was 91.4%.ConclusionsClinical results of THA using conventional cementless implants for patients with RDC were acceptable. Thus, THA using conventional cementless implant is an effective and safe surgery for patients with RDC, minimizing surgical stress.     

A case of "interval" form of acute carbon monoxide poisoning--brain MRI and therapeutic effect of hyperbaric oxygenation

A 43-year-old female who had suffered from paranoid reaction attempted suicide with city gas. She was admitted to an emergency hospital in a comatose state, regained consciousness the next day and was discharged 12 days after. However, on the 21st day after the poisoning, behavioral anomalies and staggering appeared. She was readmitted into another emergency hospital with the diagnosis of an "interval" form of acute carbon monoxide poisoning. She was performed hyperbaric oxygen therapy 42 times until the 53rd day after the accident. Nevertheless, her symptoms did not improve and remained in a state like an apallic syndrome. With little promise of improvement, she was moved to our hospital, and hyperbaric oxygen therapy further continued for 40 times which resulted in a remarkable recovery. Repeat EEGs were performed. On the 32nd day, EEG showed an abnormality consisting of generalized delta waves. On the 56th day, the abnormal EEG improved slightly with more alpha activity. EEG was normalized 126 days after. The X-ray CT scan on the 32nd day revealed low densities in the bilateral globus pallidus and the deep white matters adjacent to the frontal horns of the lateral ventricle and in the semioval centers. On the 57th day, these low density areas were depicted more clearly by the X-ray CT scan, which became less marked on the 73rd day. MRI was performed 3 times.(ABSTRACT TRUNCATED AT 250 WORDS)     

The N-Methyl-D-aspartate (NMDA) receptor antagonist dizocilpine (MK-801) suppresses enfturane-induced opisthotonus in mice

We determined whether enflurane-induced opisthotonus in ddN mice is mediated by N-methyl-D-aspartate (NMDA) receptor using NMDA receptor antagonists dizocilpine (MK-801) and ketamine. Animals were given intraperitoneal injections of 0.2ml saline (control), 2.5 or 5.0mg·kg^–1 dizocilpine in saline, or 20 or 40mg·kg^–1 ketamine is saline 20min prior to exposure to 2.0% enflurane. Incidence of opisthotonus measured during exposure to enflurane for 20min was 49% (n = 51) in saline (control) group, 6.7 (P 0.01 vs control, n = 30) and 15.0% (P 0.01, n = 40) in 2.5 and 5.0mg·kg^–1 dizocilpine group, respectively, and 43.9 (NS, n = 41) and 40.0% (NS, n = 40) in 20 and 40mg·kg^–1 ketamine group, respectively. These results strongly suggest that enflurane-induced opisthotonus is mediated by NMDA receptor. Ketamine failed to suppress significantly due to possibly small dosages. Further, dizocilpine itself produced severe seizures during preenflurane period (30.0 and 40.0% in 2.5 and 5.0mg·kg^–1, respectively), which may be a novel finding.(Komatsu H, Nogaya J, Anabuki D, et al.: The N-methyl-D-aspartate (NMDA) receptor antagonist dizocilpine (MK-801) suppresses enflurane-induced opisthotonus in mice. J Anesth 7: 519–522, 1993)     

Suppression of neointimal thickening by a newly developed HMG-CoA reductase inhibitor,BAYw6228, and its inhibitory effect on vascular smooth muscle cell growth

1. The aim of this study was to determine whether BAYw6228 (BAYw), a newly developed 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitor, could suppress an atherogenic process such as intimal thickening by a mechanism other than lowering the level of serum cholesterol.
2. First, we evaluated the in vitro effect of BAYw on the proliferation of vascular smooth muscle cells (SMC) from various species: Sprague-Dawley (SD) rats, New Zealand (NZ) white rabbits, intimal cells from Watanabe hereditary hyperlipidemic (WHHL) rabbit and SMC from the new-born human aorta. The increasing rate of total protein content of these cells was inhibited by the addition of BAYw in a dose-dependent fashion. In the presence of 2% foetal calf serum (FCS), the value of IC₅₀ was 1.0 μM in SD rats. 2.1 μM in NZ white rabbits, and 0.3 μM in WHHL rabbits. With human SMC, the value was 0.02 μM in the presence of 10% FCS and 0.2 μM with a mixture of growth factors.
3. Based on these above in vitro findings, we next examined the in vivo effect of the agent to determine whether it could suppress rabbit intimal thickening induced by balloon catheterization. A balloon catheter was inserted from a peripheral branch of the left external carotid artery to the aorta to denude the endothelium of the left common carotid artery in Japanese white rabbits. After 12 days they were divided into control and BAYw groups. The former were subcutaneously injected with saline and the latter with BAYw 1 mg kg⁻¹ day⁻¹. Two days after the beginning of treatment, a second balloon injury was performed to the previously injured left common carotid artery in both groups. After another two weeks, the left common carotid artery was removed and variously stained. Although the total serum cholesterol in the BAYw group was significantly lower than in the control (P<0.05), the difference was not enough to affect intimal thickening. In addition, the BAYw group had a smaller intima/media ratio than the control group, decreasing to 45% of control (P<0.05). By anti-α smooth muscle actin antibody staining, these intimal thickening areas were entirely occupied by SMCs, and their amount was attenuated by BAYw. By anti-rabbit macrophage antibody (RAM 11) staining, the number of positive cells in the intimal thickening was markedly decreased in the BAYw group compared to control (P<0.01).
4. These results indicate that BAYw has an inhibitory effect on intimal thickening by attenuating intimal SMC proliferation and infiltration of macrophages, suggesting that BAYw could be effective in the prevention of the progression of atherosclerotic plaque-like restenosis after angioplasty.

     

Accumulation of L-[2-(F-18)]fluorophenylalanine in peri-infarct area in a patient with acute cerebral infarction

We studied the brain uptake of amino acid in a patient with acute cerebral infarction with L-[2-(F-18)] fluorophenylalanine and positron emission tomography. The increased accumulation of the ligand was specifically found in the peri-infarct area where oxygen metabolism was still maintained but decreased later in the 72-day follow-up period. The kinetic analysis revealed that increased accumulation was not due to increased transport from the blood to the brain but to delayed washout from the brain to the blood. Although the mechanism is still unknown, abnormally high accumulation of L-[F-18]fluorophenylalanine may predict delayed neuronal changes after ischemic insults of the brain.     

Neurotoxicity and pharmacokinetics of ventriculolumbar perfusion of methyl 6-[3-(2-chloroethyl)-3-nitrosoureido]-6-deoxy-alpha-D-gluco-pyranoside (MCNU) in dogs

Summary Ventriculolumbar perfusion of methyl 6-[3-(2-chloroethyl)-3-nitrosoureido]-6-deoxy-alpha-D-glucopyranoside (MCNU), a water soluble nitrosourea with log P-0.71, may be efficacious in the treatment of subarachnoid dissemination of malignant glioma. We used 2 dogs to study the neurotoxicity and pharmacokinetics of MCNU. MCNU (1 mg), dissolved in 10 ml of artificial CSF, was administered via the right lateral ventricle during a period of 18 to 42 min and the CSF was drained by lumbar puncture. The perfusion was repeated once a week for 10 consecutive weeks. No neurological and systemic symptoms were noted after perfusion. Histological examination of the brain and spinal cord showed local denudation of the ependyma and local subependymal spongy degeneration and gliosis in the lateral ventricle into which MCNU was administered in one dog and local denudation of the ependyma in the other. When administration was over a period of 21 to 38 min, the MCNU concentration in the lumbar CSF peaked at 11.11 to 50.67 g/ml, in 28 to 78 min. The area under the drug concentration-time curve (AUC) was 1152 g×min/ml on average, significantly larger than that of ACNU. The elimination phase followed linear kinetics and the half-time was 41.1 min on average, significantly longer than that of ACNU. These findings suggest that ventriculolumbar perfusion of MCNU may be effective in the treatment of subarachnoid dissemination of malignant glioma notwithstanding some local histological changes.     

Predicting the viability of grafted livers in rats through a rapid and sensitive metabolic indicator assessed by 31P-NMR spectroscopy

The present study was undertaken to clarify whether a correlation exists between the hepatic ratio of the -phosphorous moiety of ATP (-ATP) to inorganic phosphate (Pi), measured by ³¹P nuclear magnetic resonance spectroscopy 1 h after the reestablishment of portal blood flow, and the survival rate of rats following liver transplantation. This ratio was compared with the arterial ketone body ratio [AKBR (acetoacetate/3-hydroxybutyrate)], which is accepted as a reliable indicator of liver viability. After the transplantation of fresh livers, the 1-week survival rate was 92% and the -ATP/Pi ratio was 64% of the normal level. When the liver grafts were subjected to warm ischemia for 25 min or 45 min prior to harvesting, the 1-week survival rate decreased to 43% and 0%, respectively, and the -ATP/Pi ratio dropped to 31% and 18% of the normal level, respectively. On the other hand, the AKBR was about 25% of the normal level after transplantation of fresh livers, while it was 37% and 48% after transplantation with 25 min and 45 min of warm ischemia, respectively. However, 4h after the reestablishment of portal blood flow, the AKBR correlated with the -ATP/Pi ratio in both the fresh graft group and the 45-min warm ischemic damage group. These results show that the -ATP/Pi ratio provides an accurate evaluation of a graft viability even at an extremely early stage following liver transplantation, and should prove useful for the early diagnosis of primary graft nonfunction after liver transplantation.