Fourier transform infrared spectroscopy and machine learning for Porphyromonas gingivalis detection in oral bacteria.

Porphyromonas gingivalis, a Gram-negative anaerobic bacillus, is the primary pathogen in periodontitis. Herein, we cultivated strains of oral bacteria, including P. gingivalis and the oral commensal bacteria Actinomyces viscosus and Streptococcus mutans, and recorded the infrared absorption spectra of the gases released by the cultured bacteria at a resolution of 0.5 cm-1 within the wavenumber range of 500-7500 cm-1. From these spectra, we identified the infrared wavenumbers associated with characteristic absorptions in the gases released by P. gingivalis using a decision tree-based machine learning algorithm. Finally, we compared the obtained absorbance spectra of ammonia (NH3) and carbon monoxide (CO) using the HITRAN database. We observed peaks at similar positions in the P. gingivalis gases, NH3, and CO spectra. Our results suggest that P. gingivalis releases higher amounts of NH3 and CO than A. viscosus and S. mutans. Thus, combining Fourier transform infrared spectroscopy with machine learning enabled us to extract the specific wavenumber range that differentiates P. gingivalis from a vast dataset of peak intensity ratios. Our method distinguishes the gases from P. gingivalis from those of other oral bacteria and provides an effective strategy for identifying P. gingivalis in oral bacteria. Our proposed methodology could be valuable in clinical settings as a simple, noninvasive pathogen diagnosis technique.

Classification of gases around Pseudomonas aeruginosa and Acinetobacter baumannii by infrared spectroscopy.

Gas samples were collected from the air surrounding single and mixed laboratory cultures, and preliminary data on human breath samples were also obtained. The infrared spectra of a variety of gasses were measured at high resolution (0.5 cm-1) to obtain information about the infrared absorption bands to be used as indicators. These key bands enable bacterial classification, and the discrimination rates can be improved by observing multiple infrared absorptions. The air around Pseudomonas aeruginosa was distinguished from the other gas samples by the infrared absorptions at wavenumbers of 778.4 cm-1 and 2213.2 cm-1. For Acinetobacter baumannii, infrared absorptions at 1215.0 cm-1 and 2982.3 cm-1 were used; furthermore, adding those at 4768.7 cm-1 and 5353.8 cm-1 was shown to improve identification.

Decision tree-based identification of Staphylococcus aureus via infrared spectral analysis of ambient gas.

In this study, eight types of bacteria were cultivated, including Staphylococcus aureus. The infrared absorption spectra of the gas surrounding cultured bacteria were recorded at a resolution of 0.5 cm-1 over the wavenumber range of 7500-500 cm-1. From these spectra, we searched for the infrared wavenumbers at which characteristic absorptions of the gas surrounding Staphylococcus aureus could be measured. This paper reports two wavenumber regions, 6516-6506 cm-1 and 2166-2158 cm-1. A decision tree-based machine learning algorithm was used to search for these wavenumber regions. The peak intensity or the absorbance difference was calculated for each region, and the ratio between them was obtained. When these ratios were used as training data, decision trees were created to classify the gas surrounding Staphylococcus aureus and the gas surrounding other bacteria into different groups. These decision trees show the potential effectiveness of using absorbance measurement at two wavenumber regions in finding Staphylococcus aureus.

Investigation of Various Organic Radicals Dispersed in Polymethylmethacrylate Matrices Using the Electron Spin Resonance Spectroscopy Technique.

The electron spin resonance (ESR) spectroscopy technique was used to study various organic radicals, such as 2,2,6,6-tetramethyl-1-piperidinyloxyl (TEMPO), 4-hydroxy-TEMPO (TEMPOL), 2-X-nitronylnitroxide (2-X-NN, X = Ph, NO2Ph, or cyclohexyl), 4-Y-benzonitronylnitroxide (4-Y-PhBzNN, Y = Ph or NO2Ph), and 2-Z-iminonitroxide (2-Z-IN, Z = Ph or NO2Ph) dispersed in a polymethylmethacrylate (PMMA) matrix. The experiments were conducted at room temperature. The complex nature of the recorded ESR spectra could be attributed to the superposition of the rotational diffusion component of TEMPO (or TEMPOL) in the nanospace of the PMMA matrix with the rigid-limit component. A single component of the rigid-limit was observed for 2-X-NN and 4-Y-PhBzNN radicals dispersed in the PMMA matrix. The isotropic components of g and hyperfine ( A ) tensor, estimated by analyzing the solution spectra, were used to determine the g and A components of 4-Y-PhBzNN. Only the rotational diffusion component was observed for the 2-Z-IN radical. These results demonstrated that the PMMA matrix contains cylindrical nanospaces. Various radicals other than TEMPO derivatives could be used in the ESR spin probe technique as probe molecules for determining the structures, sizes, and shapes of the nanospaces.

Antiplatelet therapy and stent thrombosis after sirolimus-eluting stent implantation.

BACKGROUND: The influences of antiplatelet therapy discontinuation on the risk of stent thrombosis and long-term clinical outcomes after drug-eluting stent implantation have not yet been addressed adequately. METHODS AND RESULTS: In an observational study in Japan, 2-year outcomes were assessed in 10 778 patients undergoing sirolimus-eluting stent implantation. Data on status of antiplatelet therapy during follow-up were collected prospectively. Incidences of definite stent thrombosis were 0.34% at 30 days, 0.54% at 1 year, and 0.77% at 2 years. Thienopyridine use was maintained in 97%, 62%, and 50% of patients at 30 days, 1 year, and 2 years, respectively. Patients who discontinued both thienopyridine and aspirin had a significantly higher rate of stent thrombosis than those who continued both in the intervals of 31 to 180 days, 181 to 365 days, and 366 to 548 days after stent implantation (1.76% versus 0.1%, P<0.001; 0.72% versus 0.07%, P=0.02; and 2.1% versus 0.14%, P=0.004, respectively). When discontinuation of aspirin was taken into account, patients who discontinued thienopyridine only did not have an excess of stent thrombosis in any of the time intervals studied. Adjusted rates of death or myocardial infarction at 24 months were 4.1% for patients taking thienopyridine and 4.1% for patients not taking thienopyridine (P=0.99) in the 6-month landmark analysis. CONCLUSIONS: Discontinuation of both thienopyridine and aspirin, but not discontinuation of thienopyridine therapy only, was associated with an increased risk of stent thrombosis. Landmark analysis did not suggest an apparent clinical benefit of thienopyridine use beyond 6 months after sirolimus-eluting stent implantation.

Responsiveness to dobutamine stimulation in patients with left ventricular apical ballooning syndrome.

To investigate the underlying mechanisms of the left ventricular (LV) apical ballooning syndrome, we evaluated the functional responsiveness to dobutamine stimulation in patients with the syndrome. Over a 22-month period, 11 consecutive patients with the apical ballooning syndrome were referred to our institution. All 11 patients were women and 57 to 85 years of age (mean 73 +/- 10). Among them, 10 patients underwent low-dose dobutamine echocardiography within 24 hours after admission (17 +/- 8 hours). Echocardiography was repeated in the convalescent phase (48 +/- 33 days) to assess functional outcome. In the resting state, all patients showed akinetic wall motion in the midportion of the left ventricle and apical left ventricle. After low-dose dobutamine infusion, akinetic wall motion detected at rest did not show any improvement despite the hypercontractile basal LV wall. In the convalescent phase, LV dysfunction was not observed on echocardiography in all 11 patients. The LV apical ballooning syndrome has a unique feature that reversible dysfunction lacks functional amelioration during dobutamine administration. In conclusion, this finding suggests that the pathophysiologic mechanisms of the syndrome appear to be distinct from those of myocardial stunning after transient ischemia, and catecholamine-mediated cardiac toxicity may play a role in the development of the syndrome.

[Skin collagen abnormalities in a Japanese patient with extracranial internal carotid artery dissection followed by extracranial vertebral artery dissection].

A 41-year-old man with hypertension and hyperlipidemia who complained of left hemiparesis after a temporal headache was admitted to our hospital. A cervical MRI with gadolinium enhancement revealed an intramural hematoma is compatible with right extracranial internal carotid artery dissection. Two weeks later, he complained of sudden onset of pain in the right side of his neck. The right extracranial internal carotid artery dissection followed by the right extracranial vertebral artery dissection was diagnosed. Spontaneous cervical artery dissection (SCAD) is one of the causes of stroke in young adults. The pathogenesis of SCAD remains unknown. Minor trauma like an excessive sneeze, migraine, and connective tissue disorders such as fibromuscular dysplasia and Ehlers-Danlos syndrome are well-known as risk factors for SCAD. Pathologically skin collagen abnormalities have been seen in German patients with SCAD without clinical evidence for any specific connective tissue disorder. We examined the ultrastructural morphology of the Japanese patient's dermal connective tissue components by electron microscopy. The patient's collagen fibers contained fibrils with highly variable diameters, and there were other ultrastructural abnormalities, including flower-like fibrils and large-diameter composite fibrils. This is the first report of a case of ultrastructural abnormalities of dermal connective tissue in a Japanese patient with SCAD.

Use of everolimus-eluting stent with a bioresorbable polymer coating for treatment of recurrent in-stent restenosis.

Recently, an everolimus-eluting stent utilizing a bioresorbabale PLA polymer coating to release the agent everolimus has proven safe and effective in preventing restenosis for up to six months in de novo coronary arteries. But the use of a bioresorbable polymer-coated everolimus-eluting stent for in-stent restenosis lesions has not been previously investigated. This is a case report of one-year angiographic follow-up results after the implantation of a bioresorbable PLA polymer-coated everolimus-eluting stent for the treatment of recurrent in-stent restenosis. The case involved a 63-year-old female who had repeatedly presented with recurrent in-stent restenosis in the LCX. We successfully treated this recurrent ISR lesion by using a bioresorbable PLA polymer-coated everolimus-eluting stent; the one-year follow-up angiography revealed prevention of ISR after the implantation of this device.

Preserved myocardial [123I]metaiodobenzylguanidine uptake in autosomal recessive juvenile parkinsonism: first case report.

A decrease in myocardial uptake of iodine-123-labeled metaiodobenzylguanidine (123I-MIBG) has been reported in idiopathic Parkinson's disease (PD) using 123I-MIBG myocardial scintigraphy. However, the patient with autosomal recessive juvenile parkinsonism (AR-JP), caused by the parkin gene, presented here showed normal 123I-MIBG myocardial uptake, suggesting that AR-JP is a distinct disease entity from PD. Although the clinical features of AR-JP are sometimes quite similar to those of late-onset idiopathic PD, 123I-MIBG myocardial scintigraphy may be a powerful tool to differentiate PD from other parkinsonian syndromes, including AR-JP.

Effectiveness of right or left radial approach for coronary angiography.

The transradial approach for catheterization is becoming increasingly more popular. At present, the choice of the right or left radial artery depends on the operator's preference. We examined how the laterality influenced the effectiveness of the approach. Employing Judkins-type catheters, we performed coronary angiography in 232 patients with the left approach and in 205 patients with the right approach. Although access time did not differ between the two groups of patients, the duration of catheter manipulation was shorter in the left- than in the right-approach group (11.7 +/- 5.9 vs. 9.8 +/- 4.4 min; P < 0.001). Because of the shorter duration of catheter manipulation, the total procedural duration was shorter in the left-approach group (13.7 +/- 6.4 vs. 11.4 +/- 4.8 min; P < 0.001). The fluoroscopy time was shorter in the left- than in the right-approach group (3.7 +/- 2.5 vs. 5.0 +/- 3.3 min; P < 0.001). The amount of contrast material did not differ between the groups (79 +/- 27 vs. 83 +/- 25 ml). The rate of guidewire usage to engage the coronary ostium was higher in the right- than in the left-approach group because of the severe tortuosity of the right subclavian artery (20/205 vs. 0/232; P < 0.001). Thus, for operators with significant experience, the left radial approach may provide increased procedural efficacy for coronary angiography compared to the right radial approach.

[Symptomatic therapies for multiple sclerosis].

In spite of the proven efficacy of the newer immunomodulative pharmacologic treatments for multiple sclerosis, such as steroid pulse therapy for exacerbation and beta-interferon subcutaneous injections for prevention, those treatments have not yet satisfied the criteria for direct management of the disease. Thus, even now, patients with multiple sclerosis still need symptomatic therapy to improve their quality of life and ameliorate the impairments in their activities of daily living due to their various neurologic deficits. This article reviews the management of a wide range of neurologic symptoms of multiple sclerosis, including spasticity, bladder dysfunction, paroxysmal symptoms, and chronic pain.

A new miniature catheter with side-holes for percutaneous transradial or transbrachial coronary angiography.

The percutaneous arm approach through the radial or brachial artery for diagnostic cardiac catheterization has advantages, such as a lower incidence of access-site complications and decreased patient discomfort, particularly when smaller diameter catheters are employed. However, the pressure produced by high-flow jets of contrast material exiting from an end-hole against the vascular wall can cause coronary dissection or myocardial blushing. To avoid this type of complication, we designed and developed a new miniature (4 French) catheter with two side-holes for coronary angiography. Under conditions similar to those of a clinical situation, we obtained the relationship between the pressure produced by the jets exiting from an end-hole and the force with which the tip of the catheter was pushed against the vascular wall. The presence of the side-holes substantially decreased the pressure at forces ranging between 0 and 15 gf, and at all injection rates (2.0 3.5 ml/second), but their location did not affect the pressure. In a preliminary clinical study, the new catheters with side-holes were feasible and effective for coronary angiography through the radial artery. Furthermore, the distribution of contrast material decreased the incidence of dislodgement of the catheter from the coronary ostia and enabled good visualization of the coronary ostia and proximal branches.