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Abstract Background Curved varus osteotomy (CVO) is an effective femoral head-preserving surgical procedure for osteonecrosis of the femoral head (ONFH) classified as type B or C1 according to the Japanese Investigation Committee (JIC) classification; it reportedly provides better postoperative outcomes than transtrochanteric rotational osteotomy (TRO). We have developed a new procedure called spherical varus rotational osteotomy (SVRO) in which osteotomy of the femur into a spherical shape is followed by varus and anterior rotation using navigation to increase indications and improve postoperative outcomes. Methods Nine joints of eight patients who underwent SVRO and could be followed up for > 1 year were included in the study. Disease types determined preoperatively according to the JIC classification were type C1 for four joints and type C2 for five joints. Preoperative disease JIC classification stages were 3a for eight joints and 1 for one joint. SVRO was performed using OrthoMap® 3D Navigation software, and the following variables were measured: surgery time, intraoperative blood loss, difference between preoperative and postoperative angles of anteversion, postoperative lower limb length discrepancy, and postoperative intact area occupancy. The Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) was used for clinical evaluation. Visual Analog Scale and JHEQ scores were evaluated preoperatively and at the final follow-up. Results The measurement results were as follows: surgery time, 130 min; blood loss, 200 ml; angle of varus, 20°; angle of anterior rotation, 30°; preoperative angle of anteversion, 15°; postoperative angle of anteversion, 22°; lower limb shortening, 11 mm; preoperative intact area occupancy, 0%; and postoperative intact area occupancy, 74.2%. There were no cases of progression in the postoperative stages or re-collapse. Conclusion SVRO allows for the repositioning of the exterior and posterior intact areas, providing a broader intact region postoperatively. This technique is particularly beneficial for young patients with ONFH and extensive necrosis and is a less invasive alternative to TRO. This procedure has been shown to be effective in achieving favorable outcomes in patients with extensive necrosis who would have otherwise required rotational osteotomy, depending on the necrosis location. Further longitudinal studies are necessary to validate these findings and establish long-term benefits.

Aims: The localization of necrotic areas has been reported to impact the prognosis and treatment strategy for osteonecrosis of the femoral head (ONFH). Anteroposterior localization of the necrotic area after a femoral neck fracture (FNF) has not been properly investigated. We hypothesize that the change of the weight loading direction on the femoral head due to residual posterior tilt caused by malunited FNF may affect the location of ONFH. We investigate the relationship between the posterior tilt angle (PTA) and anteroposterior localization of osteonecrosis using lateral hip radiographs. Methods: Patients aged younger than 55 years diagnosed with ONFH after FNF were retrospectively reviewed. Overall, 65 hips (38 males and 27 females; mean age 32.6 years (SD 12.2)) met the inclusion criteria. Patients with stage 1 or 4 ONFH, as per the Association Research Circulation Osseous classification, were excluded. The ratios of anterior and posterior viable areas and necrotic areas of the femoral head to the articular surface were calculated by setting the femoral head centre as the reference point. The PTA was measured using Palm’s method. The association between the PTA and viable or necrotic areas of the femoral head was assessed using Spearman’s rank correlation analysis (median PTA 6.0° (interquartile range 3 to 11.5)). Results: We identified a negative correlation between PTA and anterior viable areas (rho −0.477; p = 0.001), and no correlation between PTA and necrotic (rho 0.229; p = 0.067) or posterior viable areas (rho 0.204; p = 0.132). Conclusion: Our results suggest that residual posterior tilt after FNF could affect the anteroposterior localization of necrosis. Cite this article: Bone Jt Open 2024;5(5):394–400.

Purpose: This prospective multicenter study investigated the implant fixation of a cementless cup in primary total hip arthroplasty (THA) for osteoarthritis (OA) secondary to developmental dysplasia of the hip (DDH) in Japanese patients. Methods: Ten hospitals in Japan were enrolled in this study. The cohort comprised 267 hips in 228 Japanese patients who underwent primary THA for OA secondary to DDH. An acetabular cup with advanced in-growth, GRIPTION™ coating, was used in all patients. Mean age at surgery was 66.9 (range 45–89) years, and 201 patients (239 hips) were female. Of these patients, 89.1 ​% (238/267) was Crowe group I. Radiolucent lines around the cup, osteolysis, cup migration, grafted bone status, and clinical scores were evaluated preoperatively and at 6 months, 1 year, and 2 years postoperatively. Adverse events were evaluated throughout the study. Implant survivorship was assessed using the Kaplan–Meier method. Results: Nine hips had radiolucent lines ≥2 ​mm that resolved by 6 months. All cups showed bone in-growth and no cups loosened. At 2 years, the bone grafts had remodeled and incorporated in 68 ​% (43/63) of hips. There were four systemic and five surgical site events, and one procedure-related dislocation. The survivorship with cup revision as the endpoint was 99.6 ​% (95 ​% confidence interval, 97.3–99.9). All clinical scores were improved at 2 years compared with preoperatively (p ​

Abstract We previously reported the significant increase in limb muscle strength and cross-sectional area of the type IIb muscle fibers in the extensor digitorum longus (EDL) muscle in a type 2 diabetic animal model, with Spontaneously Diabetic Torii (SDT) fatty rats (n = 6) undergoing regular treadmill exercise from 8 to 16 weeks of age compared with sedentary SDT fatty rats (n = 6). This study investigated the mechanism by which exercise training prevented skeletal muscle wasting in the EDL muscle of the SDT fatty rats. The endurance exercise for 8 weeks downregulated the expression of muscle RING-finger protein-1 (an E3 ubiquitin ligase) and upregulated the expression of CD31, insulin receptor substrate-2, and phosphorylated endothelial nitric oxide synthase in the EDL muscle of 16-week-old SDT fatty rats. Endurance exercise training might reduce muscle wasting by preventing muscle degradation and increasing the angiogenic response in the EDL muscle in type 2 diabetes.

Abstract The study aim was to determine if suppressed activation of angiotensin II type 1 receptor (AT1) prevents severe muscle atrophy after denervation. The sciatic nerves in right and left inferior limbs were cut in AT1a knockout homo (AT1a−/−) male mice and wild-type (AT1a+/+) male mice. Muscle weight and cross-sectional areas of type IIb muscle fibers in gastrocnemius muscle decreased at 7 and 21 days postdenervation in both AT1a−/− mice and AT1a+/+ mice, and the reduction was significantly attenuated in the denervated muscles of AT1a−/− mice compared to the AT1a+/+ mice. Gene expressions in the protein degradation system [two E3 ubiquitin ligases (muscle RING-finger protein-1 and Atrogin-1)] upregulated at 7 days postdenervation in all denervated mice were significantly lower in AT1a−/− mice than in AT1a+/+ mice. Activations of nuclear factor κB and Forkhead box subgroup O1, and protein expression of monocyte chemoattractant protein-1 were significantly suppressed in the AT1a−/− mice compared with those in the AT1a+/+ mice. In addition, suppressed apoptosis, lower infiltration of M1 macrophages, and higher infiltration of M2 macrophages were significantly observed at 21 days postdenervation in the AT1a−/− mice compared with those in the AT1a+/+ mice. In conclusion, the AT1 receptor deficiency retarded muscle atrophy after denervation.

Abstract Background This study aims to investigate the effect of the glucagon-like peptide-1 (GLP-1) receptor agonist (GLP-1RA) liraglutide on retinal pathological findings as compared with insulin and hydralazine using an animal model of type 2 diabetes with obesity, hypertension, and hyperlipidemia. Methods Male spontaneously diabetic Torii (SDT) fatty rats at 8 weeks of age were randomly assigned to three groups: the liraglutide group (SDT-lira, n = 6) received a subcutaneous injection of liraglutide from the age of 8 to 16 weeks, the SDT-ins-hyd group (n = 6) was provided both insulin against hyperglycemia and hydralazine against hypertension to match levels of both blood glucose and blood pressure to those of the liraglutide group, and the control group of SDT fatty rats (SDT-vehicle, n = 7) and a nondiabetic control group of Sprague–Dawley rats (SD, n = 7) were injected with vehicle only. Both eyeballs of all groups were collected at the age of 16 weeks. Results Retinal thickness, which was found in the SDT-vehicle group, was significantly prevented to similar levels in both the SDT-lira and SDT-ins-hyd groups. Immunohistological analysis revealed that GLP-1 receptor was not expressed in the retina of all rats. The ocular protein expression of monocyte chemoattractant protein-1, which causes a proinflammatory situation, was significantly upregulated in all SDT fatty rats as compared to SD rats, but the expression levels were similar between all SDT fatty rats. With regard to neovascularization in the eyes, there were no significant differences in protein expressions of vascular endothelial growth factor, CD31, or endothelial nitric oxide synthase in all rats. Conclusions The present study indicates that liraglutide prevents retinal thickening, dependent on blood glucose and blood pressure levels in SDT fatty rats without ocular neovascularization. However, the effects did not improve the ocular proinflammatory state.

Abstract We investigate whether suppressing the activation of the angiotensin II type 1a receptor (AT1a) can ameliorate severe chronic tubulointerstitial damage (TID) after renal ischemia reperfusion (IR) using AT1a knockout homozygous (AT1a−/−) male mice. To induce severe chronic TID after renal IR, unilateral renal ischemia was performed via clamping of the right renal pedicle in both AT1a−/− and wild-type (AT1a+/+) mice for 45 min. While marked renal atrophy and severe TID at 70 days postischemia was induced in the AT1a+/+ mice, such a development was not provoked in the AT1a−/− mice. Although the AT1a+/+ mice were administered hydralazine to maintain the same systolic blood pressure (SBP) levels as the AT1a−/− mice with lower SBP levels, hydralazine did not reproduce the renoprotective effects observed in the AT1a−/− mice. Acute tubular injury at 3 days postischemia was similar between the AT1a−/− mice and the AT1a+/+ mice. From our investigations using IR kidneys at 3, 14, and 28 days postischemia, the multiple molecular mechanisms may be related to prevention of severe chronic TID postischemia in the AT1a−/− mice. In conclusion, inactivation of the AT1 receptor may be useful in preventing the transition of acute kidney injury to chronic kidney disease.

This paper presents a proposal of a new optical multi-context blind scrubbing that can not only increase the soft-error tolerance of the configuration memory of field programmable gate arrays (FPGAs) but also support high-speed dynamic reconfiguration suitable for accelerating FPGA operations. The optical multi-context blind scrubbing operation uses a holographic memory as a soft-error free radiation-hardened external memory. It exploits its two-dimensional large-bandwidth optical bus. Optical multi-context blind scrubbing operation was demonstrated with four configuration contexts. The soft-error tolerance of the scrubbing operation was evaluated using a radiation tolerance experiment using two 4-MBq Americium-241 alpha particle sources. Results show the worst case mean time to repair (MTTR) of the scrubbing operation as 560 ns, which can realize sufficient soft-error tolerance in radiation-rich space environments.

Abstract Background The aim of this study was to evaluate protective effects of endurance exercise training against diabetic kidney disease (DKD) with muscle weakness by using male spontaneously diabetic Torii (SDT) fatty rats as type 2 diabetic animal models with obesity, hypertension, and hyperlipidemia. Methods Eight-week-old SDT fatty rats (n = 12) and Sprague–Dawley (SD) rats (n = 10) were randomly divided into exercise (Ex; SDT-Ex: n = 6, SD-Ex: n = 5) and sedentary groups (SDT-Cont: n = 6, SD-Cont: n = 5), respectively. Each group underwent regular treadmill exercise four times a week from ages 8 to 16 weeks. Results The exercise attenuated hypertension and hyperlipidemia and prevented increases in renal parameter levels without affecting blood glucose levels. In the SDT fatty rats, it prevented induction of renal morphological abnormalities in the interstitium of the superficial and intermediate layers of the cortex. Downregulated expression of endothelial nitric oxide synthase in the glomerulus of the SDT fatty rats was significantly upregulated by the exercise. The exercise upregulated the renal expressions of both medium-chain acyl-CoA dehydrogenase and peroxisome proliferator-activated receptor γ coactivator-1α related to fatty acid metabolism. It increased muscle strength and both muscle weight and cross-sectional area of type IIb muscle fibers in the extensor digitorum longus muscle in the SDT fatty rats. Conclusion Endurance exercise training in type 2 diabetes ameliorates DKD by improving endothelial abnormality and enhancing fatty acid metabolism in addition to attenuated hypertension, hyperlipidemia, and muscle weakness independently of blood glucose levels.

The Wilms’ tumor suppressor gene, wt1, encodes a zinc finger-containing transcription factor that binds to a GC-rich motif and regulates the transcription of target genes. wt1 was first identified as a tumor suppressor gene in Wilms’ tumor, a pediatric kidney tumor, and has been implicated in normal kidney development. The WT1 protein has transcriptional activation and repression domains and acts as a transcriptional activator or repressor, depending on the target gene and context. In Xenopus, an ortholog of wt1 has been isolated and shown to be expressed in the developing embryonic pronephros. To investigate the role of wt1 in pronephros development in Xenopus embryos, we mutated wt1 by CRISPR/Cas9 and found that the expression of pronephros marker genes was reduced. In reporter assays in which known WT1 binding sequences were placed upstream of the luciferase gene, WT1 activated transcription of the luciferase gene. The injection of wild-type or artificially altered transcriptional activity of wt1 mRNA disrupted the expression of pronephros marker genes in the embryos. These results suggest that the appropriate amounts and activity of WT1 protein are required for normal pronephros development in Xenopus embryos.

This paper presents a proposal for a four-context programmable optically reconfigurable gate array (PORGA) with a high-resolution reflective silver-halide holographic memory and a corresponding writer system. The PORGA demonstrates the capability of 4.6-11.5-μs high-speed configuration context switching among four configuration contexts, which is 1000 times faster than that of conventional field programmable gate arrays (FPGAs).

Abstract.: The thienopyridine derivative ticlopidine (TCL) is an inhibitor of adenosine diphosphate-induced platelet aggregation. Combination therapy with a thienopyridine derivative and aspirin is standard after coronary stenting, although more hemorrhagic complications occur with the combination therapy than with aspirin alone. A proton pump inhibitor (PPI) is required for prevention or treatment of upper gastrointestinal bleeding in such cases. We examined the effects of PPIs [omeprazole (OPZ) and rabeprazole (RPZ)] on TCL metabolism using pooled human liver microsomes prepared from various human liver blocks and 12 individual human liver microsomes. We calculated the Ki values of each PPI for TCL metabolic activity and compared the inhibitory effect of each PPI on TCL metabolism. The Ki values of OPZ and RPZ were 1.4 and 12.7 μM, respectively. The inhibitory effect of OPZ (78.6 ± 0.05%) was significantly greater than that of RPZ (24.2 ± 0.05%) (P < 0.001). Interestingly, a negative correlation existed between the inhibitory effect of OPZ and CYP2C19 activity (r = −0.909, P < 0.001). These results suggest that the inhibitory effect of OPZ is more potent than that of RPZ in vitro. In conclusion, RPZ appears preferable when administering TCL, aspirin, and a PPI in combination. Keywords:: ticlopidine, proton-pump inhibitor, drug–drug interaction, clopidogrel, cytochrome P450 (CYP) 2C19

Paclitaxel is widely used for treatment of malignant tumors. Paclitaxel is metabolized by CYP2C8 and CYP3A4, and these enzymes are known to differ between individuals, although the details have not been clarified. Recent progress in pharmacogenetics has shown that genetic polymorphisms of metabolic enzymes are related to these individual differences. We investigated the effect of the polymorphisms on paclitaxel metabolism by analyzing metabolic activities of CYP2C8 and CYP3A4 and expressions of mRNA and protein. Production of 6α-hydroxypaclitaxel, a metabolite of CYP2C8, was 2.3-fold larger than 3′-p-hydroxypaclitaxel, a metabolite of CYP3A4. Significant inter-individual differences between these two enzyme activities were shown. The expressions of mRNA and protein levels correlated well with the enzyme activities, especially with CYP3A4. Although it was previously reported that CYP2C8*3 showed lower activity than the wild type, two subjects that had the CYP2C8*3 allele did not show lower activities in our study. Inter-individual differences in paclitaxel metabolism may be related to CYP2C8 and CYP3A4 mRNA expression. CYP2C8 is the primary metabolic pathway of paclitaxel, but there is a “shifting phenomenon” in the metabolic pathway of paclitaxel in the liver of some human subjects. Keywords:: liver, paclitaxel, CYP, polymorphism, individual difference

A relatively large amount of human liver tissue was required to determine the exact activity of human hepatic CYP3A. Although, the quantity of available human liver tissue samples is limited. We measured levels of CYP3A4 mRNA by RT-PCR with a radiolabeled primer specific for CYP3A4 and compared mRNA expression with CYP3A4 protein level and metabolic activity in liver. The level of CYP3A4 mRNA was correlated with the levels of CYP3A4 protein and activity. Our results suggest that CYP3A4 protein and activity levels can be predicted from CYP3A4 mRNA levels determined by RT-PCR and using a very small amount of liver tissue. Keywords:: human liver, CYP3A4, mRNA

ABSTRACT: Effects of KRN4884 (5-amino-N-[2-(2-chlorophenyl)ethyl]-N′-cyano-3-pyridinecarboxamidine), a novel K+ channel opener, on ionic currents were examined in rabbit femoral arterial myocytes (RFAMs). Under whole-cell clamp conditions where cells were superfused with 5.9 mM K+ bathing solution, KRN4884 elicited an outward current at -30 mV. KRN4884-induced current had a reversal potential of -78 mV and was abolished by application of glibenclamide (glib). KRN4884 was approximately 43 times more potent than levcromakalim in activating an ATP-sensitive K+ current (IK-ATP). On the other hand, KRN4884 affected neither voltage-dependent Ca2+ nor delayed rectifier K+ channel currents. In the inside-out patch clamp configuration where cells were superfused with the symmetrical 140 mM K+ solution, KRN4884 activated 47 pS K+ channels in the presence of adenosine diphosphate. Similar 47 pS K+ channels, which were reversibly inhibited by glib, were recorded under outside-out patch conditions. Using RT-PCR analysis, we found that inward rectifier K channel 6.1 (Kir6.1) and sulfonylurea 2B (SUR2B) transcripts were predominantly expressed in rabbit femoral artery. These results indicate that KRN4884 potently activates IK-ATP in RFAMs. The KRN4884-sensitive 47 pS K+ channel activity underlying IK-ATP is a vascular type KATP channel consisting of Kir6.1 and SUR2B and has similar characteristics to those of ATP-sensitive K+ channels activated by K+ channel openers in other types of smooth muscles.