Interaction of multi-walled carbon nanotubes with water-soluble proteins: effect of sidewall carboxylation.

Effect of sidewall carboxylation on protein adsorption behavior of multi-walled carbon nanotubes (MWCNTs) was studied. Two water-soluble proteins, bovine serum albumin (BSA) and egg white lysozyme (LYS), were employed in this work. Carboxylation of MWCNTs suppressed adsorption of BSA, whereas adsorption of LYS was enhanced by the carboxylation. These behaviors are explained by the difference in the dominance of hydrophobic interaction and ionic interaction between MWCNTs and the proteins.

Selective accumulation of hematoporphyrin derivative in glioma through proton-coupled folate transporter SLC46A1.

The mechanism of tumor-specific porphyrin accumulation is not clear. We investigated the expression of proton-coupled folate transporter SLC46A1 in glioma and aimed to clarify the relationship between tumor fluorescence and SLC46A1 expression.We confirmed the expression of SLC46A1 in surgical specimens from 24 glioma patients by immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR). We also investigated SLC46A1 expression in glioma cell lines by RT-PCR. The cellular uptake of hematoporphyrin derivative in vitro was measured with a microplate reader and fluorescence microscope. In these experiments, we used three human malignant glioma cell lines: U87, U251 and T98G. Immunohistochemistry showed SLC46A1 positivity in the malignant tumor lesion of each specimen. Strong positive SLC46A1 expression was observed in 33% of grade IV, 22% of grade III and 17% of grade II gliomas. All four randomly obtained malignant glioma frozen sections expressed SLC46A1 mRNA by RT-PCR. In vitro, U87 showed the least SLC46A1 expression, U251 was intermediate, and T98G showed the most expression. The amount of hematoporphyrin derivative (HpD) cellular uptake correlated with SLC46A1 expression. These results suggest that the accumulation of HpD in glioma cells is related to SLC46A1 function and SLC46A1 is involved in the mechanism of glioma fluorescence.

Transient Hemichorea-hemiballism Induced by a Combination of Postprandial Hypotension and Severe Stenosis of the Innominate Artery Concomitant with Left Carotid Occlusion.

Hemichorea-hemiballism (HCHB) due to transient ischemic attacks (TIAs) is rare. An 83-year-old woman had repeated episodes of right-sided HCHB for 3 months. Magnetic resonance (MR) angiography demonstrated occlusion of the left carotid and middle cerebral arteries and severe stenosis of the innominate artery, and 24-hour ambulatory blood pressure monitoring showed a blood pressure decrease of >20 mmHg after each meal. We speculated that HCHB developed as TIAs due to hemodynamic failure in the left cerebral hemisphere, caused by a combination of severe stenosis of the innominate artery concomitant with occlusion of the left carotid and middle cerebral arteries as well as postprandial hypotension.

Broadband THz-wave generation by satisfying the noncollinear phase-matching condition with a reflected signal beam.

We demonstrated broadband terahertz (THz) wave generation by satisfying the noncollinear phase-matching condition with a reflected signal beam. We constructed a dual-wavelength optical parametric oscillator with two potassium titanium oxide phosphate crystals pumped by a frequency-doubled Nd:YAG laser. The collinear pump and signal waves were irradiated into a lithium niobate crystal. The pump and the signal waves were reflected at the crystal surface. Because the pump and the signal waves have a finite beam diameter, when the reflected signal wave and unreflected pump wave were irradiated at the correct angle, the noncollinear phase-matching condition was satisfied. By changing the incident angle to the crystal, broadband THz-wave generation with a range of over 0.2-7.2 THz was achieved.

Biodistribution of aqueous suspensions of carbon nanotubes in mice and their biocompatibility.

In this study, we prepared two-types of water-dispersible carbon nanotubes (CNTs) and investigated their biodistribution in mice as well as bio-/cyto-compatibility. After administration, their organs were excised at various post-injection times, then observed using both optical and transmission electron microscopy (TEM). The color of the liver and lung markedly darkened, suggesting that administered CNTs reached these organs. By TEM observation, the CNTs were found in the liver and lung. They were observed even in the kidney and spleen, though their distributions in those organs were very low compared with that in liver and lung. Therefore, most of the administered CNTs would be accumulated in the liver or lung. However, the time profile of the body weight of CNT-administered mice was close to that of control mice. In addition, we estimated the cytocompatibility of the water-dispersible CNTs for hepatocytes. According to a TNF-alpha assay of the cells cultured with CNTs, the expression level was almost the same as that of the control. These results suggested that the water-dispersible CNTs have good bio-/cyto-compatibility under this condition.

Correlation Between Bone Density and Lumbar Compression Fractures.

Objectives: Bone densitometry is widely used to evaluate osteoporosis; however, it is pointed out that bone density may be high in the case of fractures, deformities, and osteosclerotic changes. The present study evaluated bone density measured at our hospital and evaluated its correlation with the presence or absence of lumbar spine fractures. Methods: Bone density of the lumbar spine and femur was measured in 185 patients from July 2017 to June 2019 at our hospital, and the presence or absence of a lumbar spine compression fracture was evaluated on the basis of the image. Information regarding age, sex, lumbar bone density, presence or absence of lumbar fracture, number of lumbar fractures, and grade of lumbar fracture was also statistically evaluated. Results: Analysis was performed for 185 patients (20 males and 165 females, average age 76.9 ± 7.5 years). The bone density was 0.830 ± 0.229 of compression fractured bodies (number of vertebral bodies were 132) and 0.765 ± 0.178 g/cm3 of noncompression fractured bodies (number of vertebral bodies was 608). Discussion: The presence of lumbar fractures significantly increases bone density. For diagnosing osteoporosis, both bone density and the possibility of lumbar spine fractures must be considered.

Size- and Morphology-Controlled Preparation of Surface-Modified Water-Dispersible Fullerene Nanoparticles for Bioapplications.

In this study, we investigated water-dispersible surface modification for size- and shape-controlled fullerene nanoparticles (C60P) based on a condensation reaction with di-amino alkane. This modification provided for water dispersibility of C60P and the capability for secondary modification as well. The resultant C60P particles have several useful physical properties: water-dispersibility for ease of injection; fluorescence for detection and quantification; and a characteristic morphology to assist identification. These properties will widely extend the applications of these particles, especially into the biological fields of bioimaging and drug delivery.

Formaldehyde reduction with scallop shell powders fired at high temperatures: Identification of the effective ingredient.

The volatile organic compound (VOC) reduction activity of scallop shell powders fired at 300, 600 and 900 degrees C was examined using formaldehyde (HCHO). Raw shells as well as fired shells immediately after firing at several temperatures, except for 600 degrees C, were found to gradually remove HCHO from the air. In the case of shell powders stored for 3 months after firing, the HCHO reduction activity of the powder fired at 900 degrees C was obviously improved, with the HCHO concentrations rapidly reaching zero within 20 min. It has been found by X-ray diffraction measurements that shell powder stored for 3 months after firing at 900 degrees C contains a small amount of calcium hydroxide (Ca(OH)2) generated from calcium oxide (CaO). Our results suggest that Ca(OH)2 may be the effective ingredient in the HCHO reduction.

Effects of Gait Treatment With a Single-Leg Hybrid Assistive Limb System After Acute Stroke: A Non-randomized Clinical Trial.

We hypothesized that a single-leg version of the Hybrid Assistive Limb (HAL) system could improve the gait and physical function of patients with hemiparesis following a stroke. In this pilot study, we therefore compared the efficacy of HAL-based gait training with that of conventional gait training (CGT) in patients with acute stroke. Patients admitted to the participating university hospital were assigned to the HAL group, whereas those admitted to outside teaching hospitals under the same rehabilitation program who did not use the HAL were assigned to the control group. Over 3 weeks, all participants completed nine 20 min sessions of gait training, using either HAL (i.e., the single-leg version of HAL on the paretic side) or conventional methods (i.e., walking aids and gait orthoses). Outcome measures were evaluated before and after the nine training sessions. The Functional Ambulation Category (FAC) was the primary outcome measure, but the following secondary outcome measures were also assessed: National Institutes of Health Stroke Scale, Fugl-Meyer Assessment (Lower Extremity), comfortable walking speed, step length, cadence, 6-min walk distance, Barthel Index, and Functional Independence Measure. In total, 22 post-stroke participants completed the clinical trial: 12 in the HAL group and 10 in the CGT group. No serious adverse events occurred in either group. The HAL group showed significant improvement in FAC after nine sessions when compared with the CGT group (P = 0.014). However, secondary outcomes did not differ significantly between the groups. Our results demonstrate that HAL-based gait therapy may improve independent walking in patients with acute stroke hemiplegia who are dependent on ambulatory assistance. A larger-scale randomized controlled trial is needed to clarify the effectiveness of single-leg HAL therapy. Clinical Trial Registration: UMIN Clinical Trials Registry, identifier UMIN000022410.

Lumbosacral subdural hematoma. Case report.

An 18-year-old man presented with a rare spinal subdural hematoma (SSH) manifesting as headache, which developed following diving into the sea the day before. Computed tomography of the head revealed no abnormality. His headache persisted followed by neck stiffness and mild lumbago. He came to see us 6 days after the first visit. He underwent lumbar puncture to eliminate the possibility of meningitis. The cerebrospinal fluid showed xanthochromia. Cerebral angiography showed no abnormality. Magnetic resonance imaging of the spine revealed lumbosacral subdural hematoma. The hematoma and his symptoms regressed spontaneously during several weeks of conservative treatment. A sharp increase in intraabdominal and/or intrathoracic pressures following diving may have caused the bleeding. Headache may be an initial symptom associated with subarachnoid hemorrhage concomitant with SSH. Delayed progression of lumbosacral SSH must be considered if the patient complains of lumbago following minor trauma.

Intracellular boron accumulation in CHO-K1 cells using amino acid transport control.

BPA used in BNCT has a similar structure to some essential amino acids and is transported into tumor cells by amino acid transport systems. Previous study groups have tried various techniques of loading BPA to increase intracellular boron concentration. CHO-K1 cells demonstrate system L (LAT1) activity and are suitable for specifying the transport system of a neutral amino acid. In this study, we examined the intracellular accumulation of boron in CHO-K1 cells by amino acid transport control, which involves co-loading with L-type amino acid esters. Intracellular boron accumulation in CHO-K1 cells showed the greatest increased upon co-loading 1.0mM BPA, with 1.0mM l-Tyr-O-Et and incubating for 60min. This increase is caused by activation of a system L amino acid exchanger between BPA and l-Tyr. The amino acid esters are metabolized to amino acids by intracellular hydrolytic enzymes that increase the concentrations of intracellular amino acids and stimulate exchange transportation. We expect that this amino acid transport control will be useful for enhancing intracellular boron accumulation.

Surgical technique for idiopathic spinal cord herniation: the Hammock method. Technical note.

Idiopathic spinal cord herniation is a rare disease, and surgical treatment is recommended for patients with motor deficits or progressive neurological symptoms. Surgery is performed to release and reposition the tethered spinal cord. In terms of repositioning and prevention of reherniation, various procedures have been proposed; enlargement of the ventral dural defect, primary closure of the defect with sutures, and insertion of a ventral patch for duraplasty. We treated 3 patients with idiopathic spinal cord herniation, using a ventral patch for duraplasty with an expanded polytetrafluoroethylene pericardial membrane (the Hammock method), and all 3 cases had good clinical outcome. The specific important technical aspects are described and illustrated. If this procedure is performed meticulously under the microscope by following the specific techniques, the Hammock method is safer and more effective for prevention of reherniation than simple enlargement of the dural defect.

Acute subdural hematoma without subarachnoid hemorrhage caused by ruptured A1-A2 junction aneurysm. Case report.

A 54-year-old man was admitted to our hospital with complaint of sudden headache. The patient had suffered two episodes of transient headache before admission. Computed tomography (CT) revealed acute subdural hematoma (ASDH) on the right side of the cerebral convexity with bilateral extension along the tentorium cerebelli without signs of subarachnoid hemorrhage (SAH) or intracerebral hemorrhage (ICH). Three-dimensional CT angiography and conventional cerebral angiography revealed a left A1-A2 junction aneurysm. Neck clipping of the aneurysm was performed. The aneurysm extended inferiorly, with the dome embedded in the chiasmatic cistern and tightly adhered to the arachnoid membrane. There was no evidence of hematoma in the subarachnoid space. The patient was discharged without neurological deficit. Ruptured aneurysms resulting in ASDH without SAH or ICH are very rare. Radiological investigation such as three-dimensional CT angiography should be performed to find the causative aneurysm in a patient with ASDH with a history of repeated headaches and without traumatic signs or episodes, and the appropriate treatment should be planned with expediency.