Femoral Neck Fracture in a Hemodialysis Patient after Liver Transplantation: A Case Report

Background

Surgical treatment of femoral neck fractures is usually performed as an urgent procedure so that restoration of the ability to stand and walk can be achieved as quickly as possible. However, orthopedic surgeons need to be aware of undertreated or untreated diseases in their patients. Organ transplant recipients require immunosuppressive agents and steroids postoperatively. Hemodialysis patients also exhibit immunological deterioration and are included among immunocompromised patients. We report a case in which conservative treatment was chosen for a hepatic transplant recipient on hemodialysis who suffered a femoral neck fracture because signs of inflammation of unknown etiology were intermittently seen.

Case

The patient was a 70-year-old man who had undergone liver transplantation from a living donor as treatment for hepatocellular cancer and hepatic failure with cirrhosis. Dialysis for end-stage renal failure was initiated at approximately 1 year postoperatively. Cyclosporine was administered as an immunosuppressive agent. The patient subsequently fell off a bicycle and was unable to walk because of right hip pain. He was brought to our hospital by ambulance, and a right hip radiograph revealed a femoral neck fracture. His white blood cell count and C-reactive protein levels were intermittently elevated with unknown etiology. Conservative treatment was finally adopted, although a bipolar hip arthroplasty was planned. At 5 months after the injury, the patient was able to walk alone in a stable manner using a pair of crutches and was discharged.

Discussion

Conservative treatment for a femoral neck fracture, which generally requires surgery, may be acceptable in organ transplant recipients on hemodialysis.

Feasibility of supplemental robot-assisted knee flexion exercise following total knee arthroplasty

BACKGROUND

The Hybrid Assistive Limb (HAL) is a robotic exoskeleton designed to support impaired limbs.

OBJECTIVE

We aimed to evaluate whether active exercise using a single-joint HAL (HAL-SJ) following total knee arthroplasty can facilitate the recovery of knee flexion.

METHODS

Twenty-two patients who underwent total knee arthroplasty were randomly allocated to the HAL-SJ group (n= 12) or conventional physical therapy (CPT) group (n= 10). On postoperative day 5, patients performed active knee flexion exercises either with or without HAL-SJ assistance every second day. Outcome measures included active and passive knee flexion range of motion (ROM), muscle strength, and pain intensity, as assessed by the visual analog scale, and were assessed on postoperative days 5 (pre-treatment) and 10 (post-treatment). Active ROM was measured at 6 months postoperatively; further long-term follow-up was performed by telephone interview.

RESULTS

Both groups showed significant improvement between postoperative days 5 and 10 in all outcome measures. Improvements in active ROM (p< 0.01), passive ROM (p< 0.01), muscle strength (p< 0.01), and pain (p< 0.01) were significantly greater in the HAL-SJ group than in the CPT group. Long-term outcomes were also significantly better in the HAL-SJ group.

CONCLUSIONS

HAL therapy enables patients to perform painless active movements and facilitates the recovery of knee function.

Severe varus knees result in a high rate of undercorrection of lower limb alignment after opening wedge high tibial osteotomy

PURPOSE

The purpose of this study was to clarify the indication for opening wedge high tibial osteotomy (OWHTO) in terms of lower limb alignment to achieve satisfactory clinical results.

METHODS

Ninety-two patients (98 knees) with medial compartment knee osteoarthritis were investigated in this study. The average follow-up period was 34 months (range, 24-68 months). The average age of the patients at the time of surgery was 63 years (range, 41-77 years).

RESULTS

The patients were divided into the following two groups according to the preoperative femorotibial angle (FTA) on anteroposterior full-length radiographs of the lower limbs while weight bearing: 29 knees with a preoperative FTA of ≥185° were defined as those with severe varus (S group), and the remaining 69 knees with a preoperative FTA of <185° were defined as those with mild varus (M group). Knees with a postoperative FTA of >175° were defined as undercorrected. The Lysholm score was used to assess the clinical results. The average postoperative FTA was 175.7° ± 4.1° in the S group and 174.6° ± 3.1° in the M group ( p = 0.013). Significantly, more undercorrected knees were observed in the S than M group ( p = 0.00035). The postoperative Lysholm score was 85.6 ± 8.5 in the S group and 88.5 ± 5.7 in the M group at the last follow-up ( p = 0.0033).

CONCLUSION

Based on these results, we recommend that a preoperative FTA of <185° should be included as a criterion for OWHTO alone.

Feasibility of Robot-assisted Rehabilitation in Poststroke Recovery of Upper Limb Function Depending on the Severity

The single-joint Hybrid Assistive Limb (HAL-SJ) robot is an exoskeleton-type suit developed for the neurorehabilitation of upper limb function. Several studies have addressed the usefulness of the robot; however, the appropriate patient selection remains unclear. In this study, we evaluated the effectiveness of the HAL-SJ exoskeleton in improving upper limb function in the subacute phase after a stroke, as a function of the severity of arm paralysis. Our analysis was based on a retrospective review of 35 patients, treated using the HAL-SJ exoskeleton in the subacute phase after their stroke, between October 2014 and December 2018. The severity of upper limb impairment was quantified using the Brunnstrom recovery stage (BRS) as follows: severe, BRS score 1–2, n = 10; moderate, BRS 3–4, n = 12; and mild, BRS 5–6, n = 13. The primary endpoint was the improvement in upper limb function, from baseline to post-intervention, measured using the Fugl-Meyer assessment upper limb motor score (ΔFMA-UE; range 0–66). The ΔFMA-UE score was significant for all three severity groups (P <0.05). The magnitude of improvement was greater in the moderate group than in the mild group (P <0.05). The greatest improvement was attained for patients with a moderate level of upper limb impairment at baseline. Our findings support the feasibility of the HAL-SJ to improve upper limb function in the subacute phase after a stroke with appropriate patient selection. This study is the first report showing the effect of robot-assisted rehabilitation using the HAL-SJ, according to the severity of paralysis in acute stroke patients with upper extremity motor deficits.

Biofeedback Core Exercise Using Hybrid Assistive Limb for Physical Frailty Patients With or Without Parkinson's Disease

Introduction: Elderly people often exhibit "frailty," and motor dysfunction occurs. Several studies have reported about the relationship between motor dysfunction and frailty in Parkinson's disease (PD). This study aimed to test whether the core exercise using the hybrid assistive limb lumbar type for care support (HAL-CB02) may improve the motor functions in frailty patients with or without PD and to explore the optimal patient selection from the frailty cohort. Materials and Methods: We recruited 16 frailty patients (PD = 8; non-PD = 8). The participants performed core exercise and squats using HAL-CB02 for five sessions a week. Outcome measures were 10-m walking test, step length, timed up-and-go test, 30-s chair stand test, and visual analog scale. Evaluation was conducted at baseline, post-exercise, and 1- and 3-month follow-ups. Results: Both PD and non-PD patients showed significant improvement in all evaluation items post-exercise. Moreover, no significant difference was found in the improvement value between the two groups. Conclusions: Our results suggest that biofeedback exercise with HAL-CB02 is a safe and promising treatment for frailty patients. Motor dysfunction in PD patients may be partly due to physical frailty, and biofeedback exercise with HAL-CB02 is proposed as a treatment option.

Patellar Dislocation in a Patient with Kabuki Syndrome with Severe Mental Retardation: A Case Report

Background

Kabuki syndrome is a rare congenital syndrome. Individuals with Kabuki syndrome have intellectual disabilities, often combined with skeletal anomalies and joint laxity. We herein report the first case of rehabilitation after reconstruction of the medial patellofemoral ligament in a patient with Kabuki syndrome.

Case

A 27-year-old woman with Kabuki syndrome and severe intellectual disability fell during an epileptic seizure. The right patella dislocated and then spontaneously reduced; similar episodes occurred repeatedly. Reconstruction of the medial patellofemoral ligament and lateral retinacular release were performed. Despite an intensive rehabilitation protocol, the patient's activities of daily living (ADL) did not quickly improve postoperatively because of her severe intellectual impairment and unwillingness to participate in rehabilitation exercises. About 3 months postoperatively, staff encouraged the patient to transfer from a wheelchair to a car, and she was able to get into the car with a little assistance. Subsequently, the patient's ADL gradually improved. By approximately 1 year postoperatively, the patient was able to ambulate independently for a few meters.

Discussion

The patient was thought to be interested in cars and in going for drives. Rehabilitation training for ADL improvement in patients with severe developmental disorders should include activities that the patients consider interesting.

A Remote-operated System to Map Radiation Dose in the Fukushima Daiichi Primary Containment Vessel

This paper describes the development of a submersible system based on a remote-operated vehicle coupled with radiation detectors to map the interior of the reactors at the Fukushima Daiichi nuclear power station. It has the aim oflocating fuel debris. The AVEXIS submersible vehicle used in this study has been designed as a low-cost, potentially disposable, inspection platform that is the smallest of its class and is capable of being deployed through a 150 mm diameter access pipe. To map the gamma-ray environment, a cerium bromide scintillator detector with a small form factor has been incorporated into the AVEXIS to identify radioactive isotopes via gamma-ray spectroscopy. This provides the combined system with the potential to map gamma-ray spectra and particle locations throughout submerged, contaminated facilities, such as Units 1, 2 and 3 of the Fukushima Daiichi nuclear power plant. The hypothesis of this research is to determine the sensitivity of the combined system in a submerged environment that replicates the combination of gamma radiation and water submersion but at lower dose rates.

Sports and Physical Activities of Elderly Patients with Medial Compartment Knee Osteoarthritis after High Tibial Osteotomy

Objective

We retrospectively investigated the preoperative and postoperative sports and physical activities (SPA) of elderly patients with medial compartment knee osteoarthritis who underwent opening-wedge high tibial osteotomy (OWHTO).

Methods

Fifty-six patients (62 knees) with medial compartment knee osteoarthritis were included in the study. The patients comprised 45 women and 11 men with a mean age at surgery of 71.6 years (range, 65-81 years). The mean follow-up period was 51±7 months. Patients who performed SPA to maintain their health for at least 30 min per session more than once a week were defined as SPA cases. The preoperative and postoperative ratios of SPA cases, the time to resuming or starting postoperative SPA, and the frequency of performing postoperative SPA were investigated. Clinical results were assessed using the Lysholm score.

Results

Fifteen patients (26.7%) performed SPA before OWHTO and 14 (25.0%) performed SPA after OWHTO (P=0.21). The mean time to resuming or starting SPA after surgery was 14.1±10.0 months, and the frequency of postoperative SPA sessions was 4.2±2.1 per week. The mean Lysholm score significantly improved from 60.8±8.9 preoperatively to 92.5±2.5 postoperatively (P<0.0001).

Conclusion

The ratio of patients who performed SPA after OWHTO was still <30% , and it took a comparatively long time for patients to resume or start SPA after surgery.

Feasibility of rehabilitation using the single-joint hybrid assistive limb to facilitate early recovery following total knee arthroplasty: A pilot study

We aimed to evaluate the feasibility of robot-assisted rehabilitation in an early postoperative setting to improve knee mobility following total knee arthroplasty (TKA). A total of 20 patients were alternatively assigned to robotassisted rehabilitation (n = 10; all women) or a control group (n = 10; 2 men and 8 women). The use of a single-joint hybrid assistive limb (HAL-SJ) in active assistive knee exercise was performed for the robot-assisted rehabilitation group while the control patients underwent conventional active assistive knee exercise. We measured the extension lag (defined as the difference between active and passive range of knee extension). We also evaluated the visual analog scale score (VAS) during active movements and active assistive movement. Concerning the extension lag, the robot-assisted rehabilitation group showed 89.4% ± 15.7% improvement (p < 0.01) while the control group showed 34.8% ± 32.1% improvement (p = 0.016). As to the VAS, the robot-assisted rehabilitation group showed 40.7% ± 23.5% improvement while the control group showed 20.4% ± 25.8% improvement (p < 0.01). The use of HAL-SJ may facilitate early recovery from knee surgery and prevent long-term complications such as quadriceps arthrogenic muscle inhibition.

Preferential Fas-mediated apoptotic execution at G1 phase: the resistance of mitotic cells to the cell death

Apoptosis is induced by various stresses generated from the extracellular and intracellular environments. The fidelity of the cell cycle is monitored by surveillance mechanisms that arrest its further progression if any crucial process has not been completed or damages are sustained, and then the cells with problems undergo apoptosis. Although the molecular mechanisms involved in the regulation of the cell cycle and that of apoptosis have been elucidated, the links between them are not clear, especially that between cell cycle and death receptor-mediated apoptosis. By using the HeLa.S-Fucci (fluorescent ubiquitination-based cell cycle indicator) cells, we investigated the relationship between the cell cycle progression and apoptotic execution. To monitor apoptotic execution during cell cycle progression, we observed the cells after induction of apoptosis with time-lapse fluorescent microscopy. About 70% of Fas-mediated apoptotic cells were present at G₁ phase and about 20% of cells died immediately after cytokinesis, whereas more than 60% of etoposide-induced apoptotic cells were at S/G₂ phases in random culture of the cells. These results were confirmed by using synchronized culture of the cells. Furthermore, mitotic cells showed the resistance to Fas-mediated apoptosis. In conclusion, these findings suggest that apoptotic execution is dependent on cell cycle phase and Fas-mediated apoptosis preferentially occurs at G₁ phase.

Hip abductor muscle strength after total hip arthroplasty with short stems

Excellent clinical results have been reported for total hip arthroplasty (THA) using a short stem. However, the range of variance in positioning of the stem has been reported to be wide. The authors hypothesized that the short stem position influences the femoral offset (FO) and hip abductor muscle strength (AMS) after surgery. The AMS was evaluated in 64 limbs in 32 patients who underwent unilateral THA using a short stem with a normal contralateral hip. The average time of AMS evaluation was 46.3 months postoperatively. The Harris Hip Score (HHS) was used for clinical evaluation. The ratio of the AMS on the reconstructed side to that on the contralateral side was calculated (strength ratio). The valgus angle (VA) of each stem and FO was measured on an anteroposterior hip radiograph. The FO ratio, as the normalized FO, was calculated. Linear regression analyses were performed to investigate the relationships among the VA, FO ratio and strength ratio. The average HHS improved from 57.7 points preoperatively to 94.6 points postoperatively. The VA negatively correlated with the FO ratio (r = -0.511, P = 0.028). The strength ratio negatively correlated with the VA (r = -0.505, P = 0.032) and positively correlated with the FO ratio (r = 0.479, P = 0.0056). The average postoperative HHS was generally satisfactory after THA using a short stem. A more valgus postoperative position of the short stem leads to reduced FO, which causes decreasing postoperative AMS after THA with a short stem.

Is the obturator artery safe when performing ischial osteotomy during periacetabular osteotomy?

The purposes of this study were (1) to evaluate the actual distance between the obturator artery and the ischial osteotomy site when performing periacetabular osteotomy via an anterior approach and (2) to determine a safe method to avoid injuring the obturator artery during this procedure. Twenty-nine hemipelves from cadavers were used in this study. The mean distance between the obturator artery and the ischial osteotomy site was 35.6 ± 7.5 mm and always exceeded 20 mm. Therefore, the procedure can be performed safely when a chisel blade of 20 mm or shorter is used.

A fast response and gamma-insensitive neutron detector based on parallel-plate avalanche counter

The use of the parallel-plate avalanche counter for slow-neutron counting is described. The choice of a suitable neutron converter is discussed on the basis of Monte Carlo simulation, and some experimental results are shown. Excellent gamma-insensitivity, high rate capability, possibility of construction in large sensitive area and low production cost are among the promising features of this neutron detector.

Differential cross sections of neutron-induced fragment-emission reactions for a microdosimetry study

Experimental differential cross sections of fragment emission (p, d, t, alpha, Li, Be and B), which were obtained for tens of mega electron volt neutrons on carbon and aluminum, using a counter telescope array and a Bragg-curve counter specially developed for neutron-induced reactions, are presented and compared with theoretical calculations using various reaction models. A calculation with the ISOBAR and GEM models was found to reproduce the experimental data except for an underestimation in non-vaporation processes. Calculations of the energy deposition by neutrons in a thin silicon layer show significant differences among the model employed.

Installation and application of an intense 7Li(p,n) neutron source for 20-90 MeV region

An intense (7)Li(p,n) neutron source was installed with the K = 110-MeV azimuthally varying field (AVF) cyclotron at the Cyclotron and Radioisotope Center (CYRIC), Tohoku University, by employing a special arrangement to allow a short target-sample distance down to 1 m. The source can deliver a neutron flux around 1.5 x 10(6) n cm(-2) s(-1) with a lithium target of thickness equivalent to 2-MeV energy loss and 3-microA proton beam, which is the highest intensity in the world. The source is successfully used for (1) measurement of neutron cross sections relevant to radiation safety and radiation effect and (2) semiconductor irradiation test for single-event effect and (3) characterisation of neutron detectors and dosemeters.

Simultaneous analysis of human plasma catecholamines by high-performance liquid chromatography with a reversed-phase triacontylsilyl silica column

The clinical importance of simultaneous analysis of 3,4-dihydroxyphenylglycol with other human plasma catecholamines has been investigated to better understand the sympathetic nervous system. However, previous reports have had analytical difficulties with both resolution and extraction. The current study uses a reversed-phase triacontylsilyl silica (C30) column under the mobile phase condition without ion-pair reagents to separate catecholamines and their metabolites, with above 91% recoveries for intra-assay, above 85% for inter-assay, and less than 10% (n=5) coefficient of variation. Lower detection limits (S/N=4) and quantification limits (S/N=6) were 40 and 100 pg/mL for norepinephrine, 3,4-dihydroxyphenylglycol, and 3,4-dihydroxyphenylalanine, 10 and 20 pg/mL for epinephrine, 10 and 40 pg/mL for dopamine. Linear ranges were from 40 to 5000 pg/mL for norepinephrine and 3,4-dihydroxyphenylalanine, from 100 to 5000 pg/mL for 3,4-dihydroxyphenylglycol, and from 10 to 2000 pg/mL for epinephrine and dopamine. The C30 column may prove clinically useful, as it provides a convenient and simultaneous method of evaluation of human plasma catecholamines.

Beam-beam limit in e+e- circular colliders

Beam-beam effects limit the luminosity of circular colliders. Once the bunch population exceeds a threshold, the luminosity increases at a slower rate. This phenomenon is called the beam-beam limit. Onset of the beam-beam limit has been analyzed with various simulation methods based on the weak-strong and strong-strong models. We have observed that an incoherent phenomenon is mainly concerned in the beam-beam limit. The simulation have shown that equilibrium distributions of the two colliding beams are distorted from Gaussians when the luminosity is limited. The beam-beam limit is estimated to be xi approximately 0.1 for a B factory with damping time of several thousand turns.

Extremely low vertical-emittance beam in the accelerator test facility at KEK

Electron beams with the lowest, normalized transverse emittance recorded so far were produced and confirmed in single-bunch-mode operation of the Accelerator Test Facility at KEK. We established a tuning method of the damping ring which achieves a small vertical dispersion and small x-y orbit coupling. The vertical emittance was less than 1% of the horizontal emittance. At the zero-intensity limit, the vertical normalized emittance was less than 2.8 x 10(-8) rad m at beam energy 1.3 GeV. At high intensity, strong effects of intrabeam scattering were observed, which had been expected in view of the extremely high particle density due to the small transverse emittance.

Decreasing process variation in the care of carotid endarterectomy patients

Avoidable complications after successful carotid endarterectomy surgery typically occur in the immediate postoperative period; most of these complications are related to hemodynamic instability. At Saint Agnes Medical Center, process variation resulted from 22 anesthesiologists and 11 surgeons doing the same process 242 ways. We introduced a Post-Anesthesia Care Unit Carotid Order Set to standardize the process, drug sequence, and drug choices for postoperative carotid endarterectomy patients. Ongoing monitoring demonstrated that this reduction in process variability resulted in a lower complication rate for stroke and wound hematoma.

Human gelsolin prevents apoptosis by inhibiting apoptotic mitochondrial changes via closing VDAC

Gelsolin is a Ca2+-dependent actin-regulatory protein that modulates actin assembly and disassembly, and is believed to regulate cell motility through modulation of the actin network. Gelsolin was also recently suggested to be involved in the regulation of apoptosis: human gelsolin (hGsn) has anti-apoptotic activity, whereas mouse gelsolin (mGsn) exerts either proapoptotic or anti-apoptotic activity depending on different cell types. Here, we studied the basis of anti-apoptotic activity of hGsn. We showed that both endogenous and overexpressed hGsn has anti-apoptotic activity, that depends on its C-terminal half. We also found that hGsn and its C-terminal half but not mGsn could prevent apoptotic mitochondrial changes such as Apsi loss and cytochrome c release in isolated mitochondria to a similar extent as Bcl-xL, indicating that hGsn targets the mitochondria to prevent apoptosis via its C-terminal half. In the same way as anti-apoptotic Bcl-xL, which we recently found to prevent apoptotic mitochondrial changes by binding and closing the voltage-dependent anion channel (VDAC), hGsn and its C-terminal half inhibited the activity of VDAC on liposomes through direct binding in a Ca2+-dependent manner. These results suggest that hGsn inhibits apoptosis by blocking mitochondrial VDAC activity.

The inhibitor of apoptosis, cIAP2, functions as a ubiquitin-protein ligase and promotes in vitro monoubiquitination of caspases 3 and 7

The inhibitor of apoptosis, cIAP2, contains a putative Ring finger motif at the C terminus. Using in vitro ubiquitination assays, we found that the Ring finger of cIAP2 alone possesses intrinsic ubiquitin ligase activity and promotes substrate-independent ubiquitination. It also promotes ubiquitination of caspases 3 and 7 but not caspase-1. The Ring fingers of c-Cbl and Apc11 failed to promote caspase-7 ubiquitination, suggesting that the Ring finger of cIAP2 itself is involved in substrate recognition.

A sandwich enzyme immunoassay for pulmonary surfactant protein D and measurement of its blood levels in drowning victims

A sensitive sandwich enzyme immunoassay for human pulmonary surfactant protein D (SP-D) was developed and used to examine the blood SP-D levels of drowning victims. Human SP-D was purified from amniotic fluid by chromatographic methods, and an antibody against human SP-D was prepared. A polystyrene ball coated with anti-SP-D IgG was incubated with purified human SP-D, and then with anti-SP-D Fab'-peroxidase conjugate. Peroxidase activity bound to the polystyrene ball was assayed by fluorometry using 3-(4-hydroxyphenyl)propionic acid as the hydrogen donor. The detection limit of human SP-D was 5.2 pg per assay tube. Examination of cross-reactions of this sandwich enzyme immunoassay with proteins from other human organs showed it to be highly specific for lung, and Northern blot analysis detected specific SP-D mRNA expression only in lung. The SP-D concentration of normal human serum was 6.4+/-2.7 (mean+/-S.D.) ng ml(-1) (n=20). The recovery rates of 0.52 ng and 5.2 ng SP-D added to 5 microl normal human serum were 93.6+/-2.7% and 93.6+/-6.1%, respectively. Blood SP-D levels of victims from the saltwater drowning group (n=14) revealed higher concentrations (105.8+/-53.7 ng ml(-1)), while freshwater drowning victims (n=12) were estimated to be 74.1+/-43.9 ng ml(-1). The SP-D levels of 15 subjects who died of hemorrhage (n=5), heart failure (n=8), traumatic shock (n=1), and electrocution (n=1) were lower (22.0+/-8.5 ng ml(-1)), and those of asphyxia victims (n=10) were slightly higher (36.2+/-17.1 ng ml(-1)) than those of other causes of death, except for drowning. These results suggest that in drowning victims, SP-D flowed into the systemic circulation by physiological and physical mechanisms, and the differences of blood SP-D levels between saltwater drowning and freshwater drowning victims are presumed to be influenced by the type of agony and/or the length of survival time in water.

Targeted expression of ced-3 and Ice induces programmed cell death in Drosophila

CED-3 is a cysteine protease required for programmed cell death in the nematode, Caenorhabditis elegans, and shares a sequence similarity with mammalian ICE (interleukin-1beta converting enzyme) family proteases. Both CED-3 and ICE family proteases can induce programmed cell death in mammalian cells. Structural and functional similarities between CED-3 and ICE family proteases indicate that the mechanism of cell death is evolutionarily conserved, suggesting the presence of a similar mechanism involving CED-3/ICE-like proteases in Drosophila. Here we determined whether CED-3 or ICE functions to induce programmed cell death in Drosophila. We have generated transformant lines in which ced-3 or Ice is ectopically expressed using the GAL4-UAS system. Expression of CED-3 and ICE can elicit cell death in Drosophila and the cell death was blocked by coexpressing the p35 gene which encodes a viral inhibitor of CED-3/ICE proteases. Results support the idea that the mechanism of programmed cell death controlled by CED-3/ICE is conserved among widely divergent animal species including Drosophila, and the system described provides a tool to dissect cell death mechanism downstream of CED-3/ICE proteases.

Bis, a Bcl-2-binding protein that synergizes with Bcl-2 in preventing cell death

Bcl-2 is the best characterized inhibitor of apoptosis, although the molecular basis of this action is not fully understood. Using a protein interaction cloning procedure, we identified a human gene designated as bis (mapped to chromosome 10q25) that encoded a novel Bcl-2-interacting protein. Bis protein showed no significant homology with Bcl-2 family proteins and had no prominent functional motif. Co-immunoprecipitation analysis confirmed that Bis interacted with Bcl-2 in vivo. DNA transfection experiments indicated that Bis itself exerted only weak anti-apoptotic activity, but was synergistic with Bcl-2 in preventing Bax-induced and Fas-mediated apoptosis. These results suggest that Bis is a novel modulator of cellular anti-apoptotic activity that functions through its interaction with Bcl-2.

Enhanced sonodynamic antitumor effect of ultrasound in the presence of nonsteroidal anti-inflammatory drugs

The antitumor effects of non-steroidal anti-inflammatory drugs, tenoxicam and piroxicam, against sarcoma 180 cells cultured in 7-week-old male mice were examined in vitro under ultrasonic irradiation. The survival rate of tumor cells when tenoxicam or piroxicam was added to sarcoma 180 suspension under ultrasonic irradiation was significantly lower than that when ultrasound alone was applied. Furthermore, when L-histidine, a scavenger of singlet oxygen and hydroxyl radical, or D-mannitol, a scavenger of hydroxyl radical, was used concurrently, the survival rate of tumor cells was significantly higher with L-histidine. From the above findings, it is surmised that tenoxicam and piroxicam increase the antitumor effects of ultrasound by increasing the production of singlet oxygen and other active oxygen species.

Cooperation of six and eya in activation of their target genes through nuclear translocation of Eya

Drosophila sine oculis and eyes absent genes synergize in compound-eye formation. The murine homologues of these genes, Six and Eya, respectively, show overlapping expression patterns during development. We hypothesized that Six and Eya proteins cooperate to regulate their target genes. Cotransfection assays were performed with various combinations of Six and Eya to assess their effects on a potential natural target, myogenin promoter, and on a synthetic promoter, the thymidine kinase gene promoter fused to multimerized Six4 binding sites. A clear synergistic activation of these promoters was observed in certain combinations of Six and Eya. To investigate the molecular basis for the cooperation, we first examined the intracellular distribution of Six and Eya proteins in transfected COS7 cells. Coexpression of Six2, Six4, or Six5 induced nuclear translocation of Eya1, Eya2, and Eya3, which were otherwise distributed in the cytoplasm. In contrast, coexpression of Six3 did not result in nuclear localization of any Eya proteins. Six and Eya proteins were coimmunoprecipitated from nuclear extracts prepared from cotransfected COS7 cells and from rat liver. Six domain and homeodomain, two evolutionarily conserved domains among various Six proteins, were necessary and sufficient for the nuclear translocation of Eya. In contrast, the Eya domain, a conserved domain among Eya proteins, was not sufficient for the translocation. A specific interaction between the Six domain and homeodomain of Six4 and Eya2 was observed by yeast two-hybrid analysis. Our results suggest that transcription regulation of certain target genes by Six proteins requires cooperative interaction with Eya proteins: complex formation through direct interaction and nuclear translocation of Eya proteins. This implies that the synergistic action of Six and Eya is conserved in the mouse and is mediated through cooperative activation of their target genes.

Identification of NRF2, a member of the NF-E2 family of transcription factors, as a substrate for caspase-3(-like) proteases

Apoptosis is mediated by members of the interleukin-1beta converting enzyme (ICE) family of proteases (caspases), which are activated by diverse stimuli, although the downstream molecular targets of caspases are still poorly understood. Using the modified yeast two-hybrid system, which we recently established to clone genes for caspase substrates, we identified NRF2 as a novel caspase substrate. NRF2 is a member of the NF-E2 family of basic region leucine-zipper transcription factors and has been shown to induce phase II detoxifying enzymes through anti-oxidant response elements. NRF2 was cleaved at two sites by recombinant caspase-3 in vitro as well as in HeLa cells during TNFalpha-mediated apoptosis. Overexpression of the C-terminal cleavage fragment containing the DNA binding and leucine-zipper domains induced apoptosis in HeLa cells. These observations suggest that NRF2 might have some role in the induction of apoptosis after cleavage by caspases.

The induction of smooth muscle alpha actin in a transformed rat cell line suppresses malignant properties in vitro and in vivo

A normal rat fibroblast 3Y1 cell line expresses smooth muscle a actin and the expression of alpha actin is suppressed in the transformant (SR-3Y1-2) induced by a Raus sarcoma virus. Gene transfer with smooth muscle alpha actin into the SR-3Y1-2 cell line reduced growth and invasiveness in vitro, as well as tumor growth and experimental lung metastasis depending on the expression of the alpha actin. These results indicated that smooth muscle alpha actin is involved in the regulation of cell growth as well as cell motility and thus leads to the suppression of malignant phenotypes in transformed cells.

Characteristics of intracardiac potentials at successful ablation sites in concealed Wolff-Parkinson-White syndrome

The authors investigated bipolar electrograms recorded from the catheter tip at the actual successful ablation sites in 22 consecutive patients with concealed Wolff-Parkinson-White syndrome to clarify the characteristics of the potentials indicating the optimal site for catheter ablation. In all patients the retrograde transaortic approach to their left-sided accessory pathways, and a temperature-controlled (60 degrees C) energy delivery, were performed. The authors assumed that a shorter dissociation time (time from energy delivery to ventriculoatrial conduction dissociation) indicated more accurate catheter mapping. A significant negative correlation (r = 0.527, p < 0.05) between the AV ratio (ratio of the amplitudes of the atrial to ventricular potentials) recorded at the ablation catheter tip and the dissociation time was observed. When the AV ratio and the dissociation time were compared among the groups classified according to the corresponding Npeak (the number of positive potential peaks in the electrogram obtained from the ablation catheter tip during right ventricular apical pacing) value, they differed significantly (p < 0.05 and p < 0.01, respectively), ie, a higher AV ratio and a shorter dissociation time related to a multipeak electrogram from the ablation catheter tip. The authors conclude that the atrial insertion site of the accessory pathway, exhibiting a multipeak complex electrogram that may represent nonuniform anisotropic characteristics, is an adequate ablation site.

Spatial coherence of bending magnet radiation and application limit of the van Cittert-Zernike theorem

In this paper we discuss how the first-order spatial coherence of bending magnet radiation is determined. We present an analytical representation of the coherence and compare it with the numerical calculations based on the first principles. It is shown that if the electron-beam size is so large that some conditions are satisfied, the van Cittert-Zernike theorem can be used without any modification in the vertical and horizontal directions. The formalism presented will be useful in judging whether or not the electron-beam size in the storage ring can be estimated directly from the van Cittert-Zernike theorem using the synchrotron radiation interferometer.

Caspase-4 and caspase-5, members of the ICE/CED-3 family of cysteine proteases, are CrmA-inhibitable proteases

Proteases of the caspase family are implicated in mammalian apoptosis and constitute a protease cascade. We characterized caspase-4 (TX/ICH-2/ICErelII) and caspase-5 (ICErelIII/TY), which are most closely related to caspase-1 (ICE) among the caspase family. Although overexpression of caspase-4 and caspase-5 induced apoptosis, confirming previous observations, this apoptosis was not inhibited by a caspase-1-specific tetrapeptide inhibitor (Ac-YVAD-CHO), suggesting that caspase-4 and caspase-5 have different substrate specificities from caspase-1 and also that caspase-4- and caspase-5-induced apoptosis is not mediated by caspase-1. CrmA, a cowpox virus-derived caspase-1 inhibitor that prevents apoptosis induced by various stimuli, was cleaved by caspase-4 and caspase-5, and inhibited their proteolytic activity as assessed by cleavage of pro-caspase-3 (pro-CPP32/Yama/apopain). Thus, caspase-4 and caspase-5 are CrmA-inhibitable proteases like caspase-1 and might be involved in apoptosis.

A cloning method for caspase substrates that uses the yeast two-hybrid system: cloning of the antiapoptotic gene gelsolin

Caspase-mediated proteolysis is a critical and central element of the apoptotic process; therefore, it is important to identify the downstream molecular targets of caspases. We established a method for cloning the genes of caspase substrates by two major modifications of the yeast two-hybrid system: (i) both large and small subunits of active caspases were expressed in yeast under ADH1 promoters and the small subunit was fused to the LexA DNA-binding domain; and (ii) a point mutation was introduced that substituted serine for the active site cysteine and thereby prevented proteolytic cleavage of the substrates, possibly stabilizing the enzyme-substrate complexes in yeast. After screening a mouse embryo cDNA expression library by using the bait plasmid for caspase-3, we obtained 13 clones that encoded proteins binding to caspase-3, and showed that 10 clones including gelsolin, an actin-regulatory protein implicated in apoptosis, were cleaved by recombinant caspase-3 in vitro. Using the same bait, we also isolated human gelsolin cDNA from a human thymus cDNA expression library. We showed that human gelsolin was cleaved during Fas-mediated apoptosis in vivo and that the caspase-3 cleavage site of human gelsolin was at D352 of DQTD352G, findings consistent with previous observations on murine gelsolin. In addition, we ascribed the antiapoptotic activity of gelsolin (which we previously reported) to prevention of a step leading to cytochrome c release from the mitochondria into the cytosol. Our results indicate that this cloning method is useful for identification of the substrates of caspases and possibly also of other enzymes.

Evidence against a functional site for Bcl-2 downstream of caspase cascade in preventing apoptosis

Apoptotic cell death is driven by ICE family proteases (caspases) and negatively regulated by Bcl-2 family proteins. Although it has been shown that Bcl-2 exerts anti-apoptotic activity by blocking a step(s) leading to the activation of caspases, a role for Bcl-2 and Bcl-xL downstream of the caspase cascade has remained unclear. Here, we show that purified active caspase-3 (CPP32/Yama/apopain) and caspase-1 (ICE) induces apoptosis when microinjected into the cytoplasm of cells, confirming our recent observations, and that the apoptosis is not at all prevented by Bcl-2 and Bcl-xL, which are overexpressed more than sufficiently to prevent Fas-mediated and overexpressed procaspase-1-mediated apoptosis. Thus, Bcl-2 and Bcl-xL do not act downstream of the caspase cascade.

Involvement of caspase-4(-like) protease in Fas-mediated apoptotic pathway

Proteases of the caspase family, especially caspase-1 (ICE)(-like), caspase-3 (CPP32/Yama/apopain)(-like) and caspase-8 (MACH/FLICE/Mch5) proteases, are implicated in Fas (APO-1/CD95)-mediated apoptosis. Here, we show that the caspase-4 (TX/ICH-2/ICE(rel)II)(-like) protease, another member of the caspase family, is also involved in Fas-mediated apoptosis, based upon the observations: (i) caspase-4 is processed in response to an agonistic anti-Fas antibody treatment, (ii) overexpression of a mutant caspase-4 with active site mutations in both p20 and p10 subunits delays Fas-mediated apoptosis, (iii) microinjected anti-caspase-4 antibodies inhibit Fas-mediated apoptosis. Together with our observations that the mutant caspase-4 inhibits the Fas-mediated activation of caspase-3(-like) proteases and purified caspase-4 cleaves pro-caspase-3 to generate a subunit of active form, these results suggest that Fas-mediated apoptosis is driven by a caspase cascade in which the caspase-4(-like) protease transmits a death signal from caspase-8 to caspase-3(-like) proteases probably through directly cleaving pro-caspase-3(-like) proteases.

Susceptibility of cerebellar granule neurons derived from Bcl-2-deficient and transgenic mice to cell death

Overproduced Bcl-2 oncoprotein has been shown to suppress cell death induced by a variety of stimuli in many cell types, including neuronal cells. Because bcl-2 is expressed in the nervous system where massive cell death is observed during development, endogenous Bcl-2 is likely to be involved in regulating neuronal cell death. Here we examined the possible role of endogenous Bcl-2 in the regulation of neuronal cell survival in the central nervous system using primary cultured cerebellar granule neurons from bcl-2-deficient, wild-type and NSE-bcl-2-transgenic mice. Cerebellar granule neurons from bcl-2-deficient mice were more susceptible than those from normal littermates to death induced by reducing the K+ concentration of the medium from high (25 mM) to low (5 mM), and neurons from bcl-2-transgenic mice were least susceptible. Similar results were obtained when cell death was induced by serum withdrawal under high K+ conditions or by the presence of etoposide, A23187 or nimodipine. Consistently, bcl-2 deficiency reduced the number of cerebellar granule neurons per mouse. These results indicate that Bcl-2 impedes neuronal cell death induced by various stimuli in a dose-dependent manner, and that endogenous levels of Bcl-2 are able to regulate neuronal cell survival in the central nervous system.

Accelerated disappearance of melanocytes in bcl-2-deficient mice

Follicular melanocytes in bcl-2(-/-) mice have been reported to turn gray during the second hair cycle. Light microscopic analysis revealed that about half of bcl-2(-/-) mouse hair shafts had no detectable melanin granules after the second hair follicle cycle, but the remaining hair appeared to be pigmented normally. After depilation to induce new anagen hair, more than 97% of the hair shafts did not have visible melanin granules in bcl-2(-/-) mice, whereas 100% of the hair shafts in bcl-2(+/+) mice were pigmented. In bcl-2(+/+) mice, dopa-positive melanocytes appeared on day 4 after depilation, whereas bcl-2(-/-) mice developed few dopa-positive melanocytes after depilation, as assessed by light and electron microscopic observation. bcl-2(-/-) mouse hair in the second hair cycle contained about 60-70% less melanin than normal mouse hair, and newly generated bcl-2(-/-) mouse hair after depilation contained a level of melanin as low as that of albino mouse hair. These observations suggest that the expression of bcl-2 might be essential for melanocyte maintenance after the second hair cycle.

[Inhibition of apoptosis by a baculovirus p35 gene]

The baculovirus gene p35 inhibits virus-induced apoptosis in insect cells. p35 can also inhibit developmentally programmed cell death in Caenorhabditis elegans and Drosophila, mammalian neuronal cell death induced by serum or NGF deprivation, and Fas- and tumor necrosis factor (TNF)-induced apoptosis in mammalian cells, indicating that p35 may interrupt an evolutionally conserved component of the death machinery. Recently it has been shown that p35 protein functions as an inhibitor of ICE/CED-3 cysteine protease family that seem to play an important role in an apoptotic pathway. This observation indicates that p35 may inhibit apoptosis by directly blocking the activities of these cysteine proteases in diverse animals.

Involvement of CPP32/Yama(-like) proteases in Fas-mediated apoptosis

Fas (Apo-1/CD95) belongs to the tumor necrosis factor/nerve growth factor receptor family and transmits apoptotic signals by binding to its ligand. Interleukin-1beta-converting enzyme (ICE), which shows substantial homology to the product of the cell death gene, ced-3, of Caenorhabditis elegans, is reported to be involved in Fas-mediated apoptosis. Using two human carcinoma-derived cell lines with undetectable levels of ICE, we found that an agonistic antihuman Fas antibody induces the activation of CPP32/Yama(-like) proteases that are ICE(-like) protease family members, and that a tetrapeptide inhibitor of CPP32/Yama protease, DEVD-CHO, inhibits the Fas-mediated activation of the proteases, Fas-mediated apoptosis, and CPP32/Yama(-like) proteolytic activities in vitro. Fas-mediated apoptosis is inhibited by the CPP32/Yama inhibitor DEVD-CHO, but not by the ICE inhibitor YVAD-CHO, suggesting a dominant role for the CPP32/Yama(-like) proteases and not ICE itself in Fas-mediated apoptosis of the human carcinoma cell lines.

The role of endothelin-1 in regulating human granulosa cell proliferation and steroidogenesis in vitro

The effects of endothelin-1 (ET-1) on luteinized human granulosa cells (L-HGCs) have not been examined. It is well known that there are differences of actions of several autocrine/paracrine regulators between L-HGCs and GCs of other species, and therefore the present study was designed to examine the effects of ET-1 1) on intracellular Ca2+ concentrations ([Ca2+]i) using the Ca(2+)-responsive fluorescent indicator Fura-2, 2) on cell proliferation by the nonradioactive method using bromodeoxyuridine, and 3) on basal and gonadotropin-stimulated steroidogenesis, and to examine the expression of ET receptor messenger RNA (mRNA) using freshly isolated and cultured L-HGCs obtained from patients undergoing in vitro fertilization. ET-1 increased [Ca2+]i in L-HGCs in a dose-dependent manner between 1 and 1000 nmol/L. High concentrations (100-1000 nmol/L) of ET-1 produced a more rapid and transient increase in [Ca2+]i than that observed with low concentrations (1-10 nmol/L) of ET-1. The increase in [Ca2+]i elicited by ET-3 (1000 nmol/L) and IRL-1620 (1000 nmol/L), a selective ETB receptor agonist, was 16% and 3% (vs. ET-1, 100%), respectively. BQ-123 (1000 nmol/L), an ETA receptor antagonist, inhibited the increase in [Ca2+]i elicited by ET-1 (by 50% at 1000 nmol/L ET-1 and by > 90% at < 500 nmol/L ET-1). mRNAs for the two known receptor subtypes (ETA and ETB) were also present in L-HGCs; however, the expression of ETA receptor mRNA was much greater than that of ETB receptors. ET-1 stimulated cell proliferation in L-HGCs in a dose-dependent manner (1000 nmol/L, 210.5 +/- 13.1%; 100 nmol/L, 198 +/- 11%; 10 nmol/L, 146 +/- 18%; and 1 nmol/L, 103 +/- 9%; vs. control, 100%). These stimulatory effects were completely blocked by BQ-123 (1000 nmol/L). ET-3 and IRL-1620 had no effects on cell proliferation in L-HGCs. Significant stimulatory effects on cell proliferation by the calcium ionophore, ionomycin (10-1000 nmol/L), were observed. ET-1, ET-3, and IRL-1620 attenuated basal progesterone secretion in L-HGCs. These results suggest that ETA receptor predominantly exist in L-HGCs and that ET-1 may stimulate cell proliferation of L-HGCs by increasing [Ca2+]i via ETA receptors.

Endothelin synthesis and receptors in human endometrium throughout the normal menstrual cycle

This study was undertaken to investigate the presence of messenger RNA (mRNA) for prepro-endothelin-I (ET-1) and the known receptor subtypes (ETA and ETB) in human endometrium at different stages of the menstrual cycle obtained at hysterectomy. Northern blot analysis revealed expression of ET-1 mRNA in human endometrium during the normal menstrual cycle. The concentration of ET-1 mRNA in endometrial tissue was greater during the menstrual and proliferative phases than during the ovulatory and secretory phases. Immunoreactive ET-1 was secreted into the medium of isolated endometrial stromal cells. Oestradiol and progesterone significantly attenuated ET-1 release in endometrial stromal cells cultured for 6 days. ETA and ETB mRNA were also present in endometrial tissue of the normal cycle. The concentration of ETA receptor mRNA was greater in the proliferative phase than in the secretory phase, whereas expression of ETB mRNA increased in menstrual phase. ET-1 significantly increased extracellular accumulation of cyclic AMP (cAMP), intracellular generation of inositol phosphates and significantly enhanced DNA synthesis in cultured endometrial stromal cells from the proliferative phase. Our results showed that human endometrial cells synthesized and released ET-1, and contained ETA and ETB receptors which were functionally coupled to phosphoinositide breakdown and to adenylate cyclase with the increase of cAMP by ET-1 stimulation. Our findings suggest that ET-1 may have a potential autocrine and/or paracrine function in human endometrial stromal cells.

bcl-2 deficiency in mice leads to pleiotropic abnormalities: accelerated lymphoid cell death in thymus and spleen, polycystic kidney, hair hypopigmentation, and distorted small intestine

Transgenic mice homozygously lacking in the bcl-2 gene were generated using homologous recombination in embryonal stem cells. The complete absence of Bcl-2 alpha and -beta proteins did not interfere with normal embryonic development. Abnormalities became evident after birth, although the severity varied among homozygous null mice, bcl-2-/- mice displayed pleiotropic abnormalities similar to those in the previously described bcl-2-/- mice, including growth retardation, smaller ears, short lives, polycystic kidney, atrophic thymus and spleen with accelerated apoptotic cell death of lymphocytes, and hair hypopigmentation in the second hair follicle cycle. Our bcl-2-/- mice also revealed novel defects in the small intestine, characterized by retarded development, accelerated exfoliation of epithelial cells, and very few mitotic progenitor cells.

Autocrine/paracrine function of transforming growth factor-beta 1 in porcine granulosa cells

The present study was undertaken to investigate the effects of transforming growth factor (TGF)-beta 1 on ovarian steroidogenesis in immature or moderately mature porcine granulosa cells in vitro. TGF-beta 1 (0.01-10 ng/ml) significantly attenuated progesterone release from the basal and follicle stimulating hormone-stimulated porcine granulosa cells, and significantly increased DNA synthesis. TGF-beta 1 also significantly increased the extracellular accumulation of cyclic AMP, but did not change the production of inositol phosphate or the intracellular calcium concentration in these cells. Thus, TGF-beta 1 appears to have a direct effect on porcine granulosa cell function, regulating the differential synthesis of progesterone mainly via the intracellular signal transduction of the cyclic AMP-protein kinase A pathway. This growth factor may play a physiologically significant role in controlling differentiation of immature and moderately mature porcine granulosa cells via an autocrine/paracrine mechanism.