Diagnostic Accuracy of Diastolic Fractional Flow Reserve for Functional Evaluation of Coronary Stenosis

Background

In the resting conditions, narrowing the window of coronary pressure measurements from the whole cardiac cycle to diastole improves diagnostic performance of coronary pressure–derived physiological index. However, whether this also applies to the hyperemic conditions has not yet been thoroughly evaluated.

Objectives

The purpose of this study was to assess whether diastolic fractional flow reserve (diastolic FFR) has better diagnostic performance in identifying ischemia-causing coronary lesions than conventional FFR in a prospective, multicenter, and independent core laboratory–based environment.

Methods

In this prospective multicenter registry at 29 Japanese centers, we compared the diagnostic performance of FFR, diastolic FFR, resting distal to aortic coronary pressure (Pd/Pa), and diastolic pressure ratio (dPR) using myocardial perfusion scintigraphy (MPS) as the reference standard in 378 patients with single-vessel coronary disease.

Results

Inducible myocardial ischemia was found on MPS in the relevant myocardial territory of the target vessel in 85 patients (22%). In the receiver-operating curve analyses, diastolic FFR had comparable area under the curve (AUC) compared with FFR (AUC_{diastolic FFR}: 0.66; 95% confidence interval [CI]: 0.58-0.73, vs AUC_FFR: 0.66; 95% CI: 0.58-0.74, P = 0.624). FFR and diastolic FFR showed significantly larger AUCs than resting Pd/Pa (0.62; 95% CI: 0.54-0.70; P = 0.033 and P = 0.046) but did not show significantly larger AUCs than dPR (0.62; 95% CI: 0.55-0.70; P = 0.102 and P = 0.113).

Conclusions

Diastolic FFR showed a similar diagnostic performance to FFR as compared with MPS. This result reaffirms the use of FFR as the most accurate invasive physiological lesion assessment. (Diagnostic accuracy of diastolic fractional flow reserve (d-FFR) for functional evaluation of coronary stenosis; UMIN000015906)

HMGA1a induces alternative splicing of estrogen receptor alpha in MCF-7 human breast cancer cells

The high-mobility group A protein 1a (HMGA1a) protein is known as an oncogene whose expression level in cancer tissue correlates with the malignant potential, and known as a component of senescence-related structures connecting it to tumor suppressor networks in fibroblasts. HMGA1 protein binds to DNA, but recent studies have shown it exerts novel functions through RNA-binding. Our previous studies have shown that sequence-specific RNA-binding of HMGA1a induces exon-skipping of Presenilin-2 exon 5 in sporadic Alzheimer disease. Here we show that HMGA1a induced exon-skipping of the estrogen receptor alpha (ERα) gene and increased ERα46 mRNA expression in MCF-7 breast cancer cells. An RNA-decoy of HMGA1a efficiently blocked this event and reduced ERα46 protein expression. Blockage of HMGA1a RNA-binding property consequently induced cell growth through reduced ERα46 expression in MCF-7 cells and increased sensitivity to tamoxifen in the tamoxifen-resistant cell line, MCF-7/TAMR1. Stable expression of an HMGA1a RNA-decoy in MCF-7 cells exhibited decreased ERα46 protein expression and increased estrogen-dependent tumor growth when these cells were implanted in nude mice. These results show HMGA1a is involved in alternative splicing of the ERα gene and related to estrogen-related growth as well as tamoxifen sensitivity in MCF-7 breast cancer cells.

HMGA1a Induces Alternative Splicing of the Estrogen Receptor-αlpha Gene by Trapping U1 snRNP to an Upstream Pseudo-5' Splice Site

Objectives: The high-mobility group A protein 1a (HMGA1a) protein is known as a transcription factor that binds to DNA, but recent studies have shown it exerts novel functions through RNA-binding. We were prompted to decipher the mechanism of HMGA1a-induced alternative splicing of the estrogen receptor alpha (ERα) that we recently reported would alter tamoxifen sensitivity in MCF-7 TAMR1 cells.

Methods: Endogenous expression of full length ERα66 and its isoform ERα46 were evaluated in MCF-7 breast cancer cells by transient expression of HMGA1a and an RNA decoy (2′-O-methylated RNA of the HMGA1a RNA-binding site) that binds to HMGA1a. RNA-binding of HMGA1a was checked by RNA-EMSA. In vitro splicing assay was performed to check the direct involvement of HMGA1a in splicing regulation. RNA-EMSA assay in the presence of purified U1 snRNP was performed with psoralen UV crosslinking to check complex formation of HMGA1a-U1 snRNP at the upstream pseudo-5′ splice site of exon 1.

Results: HMGA1a induced exon skipping of a shortened exon 1 of ERα in in vitro splicing assays that was blocked by the HMGA1a RNA decoy and sequence-specific RNA-binding was confirmed by RNA-EMSA. RNA-EMSA combined with psoralen UV crosslinking showed that HMGA1a trapped purified U1 snRNP at the upstream pseudo-5′ splice site.

Conclusions: Regulation of ERα alternative splicing by an HMGA1a-trapped U1 snRNP complex at the upstream 5′ splice site of exon 1 offers novel insight on 5′ splice site regulation by U1 snRNP as well as a promising target in breast cancer therapy where alternative splicing of ERα is involved.

Chip-based quantum key distribution

Improvement in secure transmission of information is an urgent need for governments, corporations and individuals. Quantum key distribution (QKD) promises security based on the laws of physics and has rapidly grown from proof-of-concept to robust demonstrations and deployment of commercial systems. Despite these advances, QKD has not been widely adopted, and large-scale deployment will likely require chip-based devices for improved performance, miniaturization and enhanced functionality. Here we report low error rate, GHz clocked QKD operation of an indium phosphide transmitter chip and a silicon oxynitride receiver chip—monolithically integrated devices using components and manufacturing processes from the telecommunications industry. We use the reconfigurability of these devices to demonstrate three prominent QKD protocols—BB84, Coherent One Way and Differential Phase Shift—with performance comparable to state-of-the-art. These devices, when combined with integrated single photon detectors, pave the way for successfully integrating QKD into future telecommunications networks.

Quantum key distribution has not been widely adopted in part due to technical hurdles preventing it being fully integrated in classical communication networks. Here the authors report quantum key distribution between two photonic chips manufactured with state-of-the-art telecoms industry processes.

Obesity attenuates D2 autoreceptor-mediated inhibition of putative ventral tegmental area dopaminergic neurons

The ventral tegmental area (VTA) in the midbrain is important for food reward. High‐fat containing palatable foods have reinforcing effects and accelerate obesity. We have previously reported that diet‐induced obesity selectively decreased the spontaneous activity of VTA GABA neurons, but not dopamine neurons. The spontaneous activity of VTA dopamine neurons is regulated by D₂ autoreceptors. In this study, we hypothesized that obesity would affect the excitability of VTA dopamine neurons via D₂ autoreceptors. To examine this hypothesis, we compared D₂ receptor‐mediated responses of VTA dopamine neurons between lean and obese mice. Mice fed on a high‐fat (45%) diet and mice fed on a standard diet were used as obese and lean models, respectively. Brain slice preparations were made from these two groups. Spontaneous activity of VTA neurons was recorded by extracellular recording. Putative VTA dopamine neurons were identified by firing inhibition with a D₂ receptor agonist quinpirole, and electrophysiological criteria (firing frequency <5 Hz and action potential current duration >1.2 msec). Single‐dose application of quinpirole (3−100 nmol/L) exhibited similar firing inhibition of putative VTA dopamine neurons between lean and obese mice. In stepwise application by increasing quinpirole concentrations of 3, 10, 30, and 100 nmol/L subsequently, quinpirole‐induced inhibition of firing decreased in putative VTA dopamine neurons of obese mice compared with those of lean mice. In conclusion, high‐fat diet‐induced obesity attenuated D₂ receptor‐mediated inhibition of putative VTA dopamine neurons due to the acceleration of D₂ receptor desensitization.

High‐fat diet‐induced obesity did not affect firing properties of putative ventral tegmental area (VTA) dopamine neurons. However, obesity attenuated dopamine D₂ receptor‐mediated inhibition of putative VTA dopamine neurons due to the acceleration of receptor desensitization. In obesity, decrease in D₂ receptor‐mediated autoinhibition may contribute to pathophysiology of reinforcing process in feeding.

Obesity decreases excitability of putative ventral tegmental area GABAergic neurons

Palatable food has reinforcing effects on feeding and accelerates obesity. Alteration of food-related behavior in obesity may promote maintenance of obesity. The ventral tegmental area (VTA) of the midbrain is important for food reward. However, it is unknown whether activity of VTA neurons is altered in diet-induced obesity. In this study, we examined VTA neuronal activity using an electrophysiological technique in diet-induced obese mice. Male 4-week-old mice were fed a high-fat diet or a standard diet for 5–6 weeks. Mice fed a high-fat diet gained greater body weight with heavier visceral fat compared with those fed a standard diet. Brain slice preparations were obtained from the lean and obese mice. Spontaneous activity of VTA neurons was recorded extracellularly. We found a negative correlation between firing frequency (FF) and action potential (AP) current duration in lean and obese mice VTA neurons. VTA neurons were classified as group-1 neurons (FF <5.0 Hz and AP current duration >1.2 msec) or group-2 neurons (FF ≧5.0 Hz and AP current duration ≦1.2 msec). FF, AP current duration, and firing regularity of VTA group-1 neurons were similar between lean and obese mice. Obese mice VTA group-2 neurons had a lower FF and shorter AP current duration compared with lean mice. In conclusion, obesity minimally affects VTA group-1 neurons, which are presumed to be dopaminergic, but decreases excitability of VTA group-2 neurons, which are presumed to be GABAergic. This differential effect may contribute to the pathophysiology of reward-related feeding in obesity.

Observation of the three-state dressed states in circuit quantum electrodynamics

We have investigated the microwave response of a transmon qubit coupled directly to a transmission line. In a transmon qubit, owing to its weak anharmonicity, a single driving field may generate dressed states involving more than two bare states. We confirmed the formation of three-state dressed states by observing all of the six associated Rabi sidebands, which appear as either amplification or attenuation of the probe field. The experimental results are reproduced with good precision by a theoretical model incorporating the radiative coupling between the qubit and the microwave.

Localization and interaction effects in ultrathin epitaxial NbN superconducting films

For epitaxial NbN films with thickness d, 2.0 nm ≤ d ≤ 20.5 nm, we observed a sharp superconducting transition, for which the transition temperature T(c) monotonically decreased with increasing 1/d. Regarding the suppression of T(c), the sheet resistance R(sq) dependence of T(c) closely fitted the Finkel'stein formula from localization theory, with a reasonable value of the electron mean free path comparable to atomic distance, which was used as a fitting parameter. On the other hand, the critical sheet resistance R(c), at which the superconducting-insulator transition was expected, was approximately one-third of the universal value R(q) = h/4e(2) suggested by the dirty boson model for self-duality. It is concluded that T(c) depression in the present NbN system is determined by localization theory but not the dirty boson model.

Multi-platform experiment to cross a boundary between laboratory and real situational studies: experimental discussion of cross-situational consistency of driving behaviors

We constructed an innovative experimental platform to study cross-situational consistency in driving behavior, conducted behavioral experiments, and reported the data obtained in the experiment. To discuss cross-situational consistency, we separated situations in which people use some systems to conduct tasks into three independent conceptual factors: environment, context, and system. We report the experimental results with the following systems: a laboratory system with a gaming controller and steering/pedal controllers and a real system, COMS an instrumented vehicle. The results are summarized as follows. 1) The individual behaviors in each system were stable, and consistency was retained. 2) The consistency of the behaviors was also confirmed when the participants drove using different interfaces in identical systems. 3) However, only slight correlation was observed across different systems in a specific situation where a strong high-order cognitive constraint (i.e., rapid driving) and a weak low-order cognitive constraint (driving with easy handling toward a straight-line course) were given.

Chronic tongue ulceration resolved by sulpiride: a report of two cases

We report two patients with chronic tongue ulceration who were successfully treated using sulpiride. The clinical diagnosis was oral candidiasis related to long-term steroid treatment. The results of the culture test and cytological examination supported this diagnosis, but antifungal treatment was ineffective and the tongue pain in these patients became more severe. Furthermore, the pain could not be relieved by nonsteroidal anti-inflammatory drugs (NSAIDs). We therefore prescribed sulpiride in addition to NSAIDs to reduce the tongue pain. A consequent improvement in both pain severity and ulceration was observed 2-3 weeks after sulpiride administration.

Engineering of implantable cartilaginous structures from bone marrow-derived mesenchymal stem cells

Fabrication of implantable cartilaginous structures that could be secured in the joint defect could provide an alternative therapeutic approach to prosthetic joint replacement. Herein we explored the possibility of using biodegradable hydrogels in combination with a polyglycolic acid (PGA) scaffold to provide an environment propitious to mesenchymal stem cells (MSCs) chondrogenic differentiation. We examined the influence of type I collagen gel and alginate combined with PGA meshes on the extracellular matrix composition of tissue-engineered transplants. MSCs were isolated from young rabbits, expanded in monolayers, suspended in each hydrogel, and loaded on PGA scaffolds. All constructs (n=48) were cultured in serum-free medium containing transforming growth factor beta-1, under dynamic conditions in specially designed bioreactors for 3-6 weeks. All cell-polymer constructs had a white, shiny aspect, and retained their initial size and shape over the culture period. Their thickness increased substantially over time, and no shrinkage was observed. All specimens developed a hyalin-like extracellular matrix containing glycosaminoglycans (GAGs) and type II collagen, but significant differences were observed among the three different groups. In PGA/MSCs and collagen-PGA/MSCs constructs, the cell growth phase and the chondrogenic differentiation phase of MSCs occurred during the first 3 weeks. In alginate-PGA/MSCs constructs, cells remained round in the hydrogel and cartilage extracellular matrix deposition was delayed. However, at 6 weeks, alginate-PGA/MSCs constructs exhibited higher contents of GAGs and lower contents of type I collagen. These results suggest that the implied time for the transplantation of in vitro engineered constructs depends, among other factors, on the nature of the scaffold envisioned. In this study, we demonstrated that the use of a composite hydrogel-PGA scaffold supported the in vitro growth of implantable cartilaginous structures cultured in a bioreactor system.

Tongue pain: burning mouth syndrome vs Candida- associated lesion

OBJECTIVE

We investigated patients with tongue pain to examine whether the differential diagnosis of burning mouth syndrome and Candida-associated lesion was possible.

PATIENTS AND METHODS

Sixty patients with tongue pain were divided into three groups according to the intensity of pain at rest and that when eating using the visual analogue scale: Group A: Functional pain group. Group B: Non-functional pain group. Group C: Mixed pain group. Antifungal treatment was scheduled for patients suspected clinically, mycologically or cytologically as having candidal infection.

RESULTS

The results of the culture test and direct examination indicated that group A was different from others by its high positivity for Candida, a good response to the antifungal treatment was obtained. On the other hand, antifungal treatment was not useful in group B, and the low possibility of Candida infection in the direct examination supported the result in this group. In group C, the positivity of Candida and the effect of the antifungal treatment were between groups A and B.

CONCLUSION

These results may suggest that tongue pain in group A is Candida-associated, that in group B is burning mouth syndrome-induced and that of group C is mixed conditions.

Partial atrophic tongue other than median rhomboid glossitis

A group of 23 patients with partial atrophic change of the tongue was examined for candidiasis. All of them reported pain in the tongue on eating hot or spicy food. The intensity of the tongue pain was evaluated before and after treatment using a visual analogue scale. Of the 23 patients, 10 (43.5%) had predisposing factors for candidiasis such as diabetes mellitus and anaemia. In the culture examination, candidal species were isolated in 65.2%, all Candida albicans. Direct cytological examination performed in 10 of the 23 patients revealed fungal pseudohyphae in 8 patients. After antifungal treatment, tongue pain had disappeared or improved markedly in 82.6%. Simultaneously, the filiform papilla of the atrophic site was observed to have begun to regenerate in these patients. Candida infection should be suspected in patients with partial atrophic tongue associated with pain on eating.

Cheilitis as a variation of Candida-associated lesions

OBJECTIVE

Occasionally, the clinical diagnosis of Candida-associated lesion is difficult because of a variety of its clinical manifestations. There have been a few reports on Candida-associated lip lesion except angular cheilitis. In this paper, we investigate the relation of Candida in persistent lesions of the lip.

SUBJECTS AND METHODS

The present study includes consecutive nine patients with persistent erosive lip lesion. For each patient the age at presentation, gender, duration of the disease, other symptoms or signs, complete medical history and prior treatment or medications for the symptom were obtained. Then, mycological examination and the direct cytologic examination were performed.

RESULTS

The reported average duration of the disease was 7 months. Six of nine patients had received prior treatments with topical steroids at the other clinic, which failed to resolve their symptoms. Six of nine patients had a predisposing factor for candidiasis. In the culture examination, Candida albicans were isolated in seven patients (77.8%). Five of nine patients received the direct cytologic examination, and four of them revealed pseudohyphae of fungi. The anti-fungal treatment was miconazol gel 25 mg four times per day, and average duration of the treatment was 2 weeks. The outcome was as follows: complete remission in five, remarkable response in two and no response in two.

CONCLUSION

Our results suggested that one form of the varieties of Candida-associated lesions might be considered in the case of lip lesion with unknown origin that was persistent and ineffective to the topical steroids treatment.

PRKAR1A gene mutation in patients with cardiac myxoma

BACKGROUND

PRKAR1A gene encodes the type 1A regulatory subunit of protein kinase A. The mutation of this gene causes Carney complex which is an autosomal dominant multiple neoplasia syndrome characterized by spotty pigmentations, endocrine overactivity and cardiac myxoma. We hypothesized that cardiac myxoma may be associated with PRKAR1A gene mutation and determined whether mutation in the PRKAR1A gene is the cause of familial and sporadic cardiac myxoma.

METHODS

We studied seven patients (three males and four females) with cardiac myxoma. Two of them had familial cardiac myxoma complicated with Carney complex. The other five patients were characterized as sporadic cardiac myxomas. We analyzed the PRKAR1A gene of all patients by the polymerase chain reaction (PCR)-single-strand conformation method, followed with direct sequence analysis.

RESULTS

We identified a novel mutation (494delTG) in exon 4A of the PRKAR1A gene in the patients with Carney complex. A 16-year-old proband had a left atrial myxoma, pituitary adenoma and skin pigmentation. His father also had left atrial myxoma and skin pigmentation. In contrast, no mutations in the PRKAR1A gene were identified in the other five patients with sporadic cardiac myxomas.

CONCLUSIONS

These results suggest that mutation of the PRKAR1A gene may be associated with familial cardiac myxoma in Carney complex but may not be associated with sporadic cardiac myxoma.

A new acellular vascular prosthesis as a scaffold for host tissue regeneration

OBJECTIVE

In situ tissue engineering using acellular xenografts is a new approach to autologous tissue regeneration. In the present study, we analyzed a new regeneration scaffold comprised of xenogenic acellular vessels in a dog model.

DESIGN OF STUDY AND RESULTS

Xenogenic vascular conduits of porcine carotid arteries were acellularized by a 48-hour detergent incubation to extract all the cell components of the graft. The acellularisation procedure resulted in a complete removal of all cells. After this procedure, heparinization was performed sequentially to induce antithrombogenicity in the graft. The burst pressure of the graft was tested. The bursting pressure of the fresh vessels was 2.83 +/- 0.56 x 10(3) mmHg (377 +/- 75kPa, n = 6). After detergent treatment, the bursting pressure of the grafts was 2.50 +/- 0.48 x 10(3) mmHg (334 +/- 63 kPa, n = 6); after heparinization, it was 3.44 +/- 0.38 x 10(3) mmHg (459 +/- 51 kPa, n = 5). In vivo function was tested in a dog model by transplantation to the abdominal artery. By 18 weeks, endothelial cells were aligned as in normal, healthy artery over the surface of the entire graft. Fibroblasts and macrophages had infiltrated the graft from both inside and outside. The neointima contained normal layers of smooth muscle cells, which were identified by anti alpha-smooth muscle fiber antigen staining.

CONCLUSIONS

The acellular heparinized xenograft has sufficient mechanical properties and was successfully replaced with host tissue, and is thus a promising new type of vascular prosthesis.

QT dispersion and left ventricular morphology in patients with hypertrophic cardiomyopathy

OBJECTIVE

To evaluate the relation between QT variables and disproportion of left ventricular wall hypertrophy in patients with hypertrophic cardiomyopathy.

DESIGN

Retrospective analysis of the results of echocardiography and electrocardiography.

SETTING

University hospital (tertiary referral centre).

PATIENTS

70 patients with hypertrophic cardiomyopathy were divided into four groups according to the distribution of left ventricular wall hypertrophy on cross sectional echocardiography: group A--hypertrophy confined to the interventricular septum; group B--hypertrophy confined to the interventricular septum and left ventricular anterior wall; group C--hypertrophy confined to the interventricular septum, left ventricular anterior wall, and lateral free wall; group D--hypertrophy involving all portions of the left ventricle.

MAIN OUTCOME MEASURES

QT intervals and QT dispersion in precordial six lead ECGs.

RESULTS

There were no significant differences in the maximum left ventricular wall thickness among the four groups, and maximum and minimum QTc intervals also did not differ. QTc dispersion was increased significantly in groups A and B compared with groups C and D. Dispersions of the interval from the J point to the end of the T wave (JTc dispersions) in groups A and B were also increased significantly compared with groups C and D. By linear regression analysis, QTc and JTc dispersions correlated with the ratio of the interventricular septal thickness to left ventricular posterior wall thickness (p = 0.0152 and p = 0.0075, respectively).

CONCLUSIONS

QT dispersion may be affected by not only electrical inhomogeneity but also by morphological inhomogeneity of the left ventricle in patients with hypertrophic cardiomyopathy.

A biodegradable nanofiber scaffold by electrospinning and its potential for bone tissue engineering

Microporous, non-woven poly( epsilon -caprolactone) (PCL) scaffolds were made by electrostatic fiber spinning. In this process, polymer fibers with diameters down to the nanometer range, or nanofibers, are formed by subjecting a fluid jet to a high electric field. Mesenchymal stem cells (MSCs) derived from the bone marrow of neonatal rats were cultured, expanded and seeded on electrospun PCL scaffolds. The cell-polymer constructs were cultured with osteogenic supplements under dynamic culture conditions for up to 4 weeks. The cell-polymer constructs maintained the size and shape of the original scaffolds. Scanning electron microscopy (SEM), histological and immunohistochemical examinations were performed. Penetration of cells and abundant extracellular matrix were observed in the cell-polymer constructs after 1 week. SEM showed that the surfaces of the cell-polymer constructs were covered with cell multilayers at 4 weeks. In addition, mineralization and type I collagen were observed at 4 weeks. This suggests that electrospun PCL is a potential candidate scaffold for bone tissue engineering.

Production of a biologically active epidermal growth factor fusion protein with high collagen affinity

Collagen is generally incapable of capturing polypeptides such as growth factors in a specific manner. In this study, we established a collagen-binding growth factor (FNCBD-EGF) consisting of epidermal growth factor (EGF) and the fibronectin collagen-binding domain. A typical yield of FNCBD-EGF was approximately 200 microg/ml culture in an Escherichia coli expression system. This fusion protein bound to gelatin and fibrillar collagen sponges, and the bound protein was not effectively eluted even with 2 M NaCl. In addition, FNCBD-EGF bound to type I, II, III, or IV collagen-coated plates, and the specificity of binding was confirmed by competitive inhibition using fibronectin. FNCBD-EGF substantially stimulated cell growth after binding to collagen-coated culture plates, whereas EGF had no effect, indicating that this fusion protein acted as a collagen-associated growth factor. In an animal model of impaired wound healing, FNCBD-EGF, but not EGF, was retained with collagen sponges at wound sites 4 d after implantation, and repair of epidermis was observed underneath the sponges. These results suggested that our fusion protein with high collagen affinity would be useful for wound healing.

Biodegradation of photosynthetically produced extracellular organic carbon from intertidal benthic algae

14C-labeled extracellular products of a natural microphytobenthic community and two species of benthic diatoms (Nitzschia hybridaeformis and Amphora coffeaeformis) were fractionated into extracellular dissolved organic carbon (14C-EDOC), organic carbon extracted with EDTA (14C-EDTA-extractable OC) and extracellular polymeric substances (14C-EPS). The biodegradation of this labeled extracellular organic carbon by bacteria in sediments was examined to determine the processes of enzymatic degradation of photosynthetically-produced extracellular organic carbon from microphytobenthos in an intertidal flat ecosystem. In addition, primary production as well as extracellular enzyme activities (beta- and alpha-glucosidase) were measured to evaluate the possible relationship between organic carbon production and microbiological degradation at the Isshiki intertidal flat in Mikawa Bay, Japan. With all three 14C-fractions extracted from a natural microphytobenthic assemblage and two species of benthic diatoms, more than 50% of the added substrates were mineralized within 24 h by the bacterial community in sediments. At that time, the percentage of high-molecular-weight compounds (>5 K MW) to total MW compounds of 14C-EDTA-extractable OC and 14C-EPS fractions decreased within 24 h from 50.9 to 6.6% and 74.5 to 11.1%, respectively. In situ, beta- and alpha-glucosidase activity in sediment was higher than in the seawater column (at a depth of 1 m), though the photosynthetic production of microphytobenthos was equal to that of phytoplankton. Based on our previous studies that microphytobenthos produced much more extracellular products than phytoplankton, it is assumed from these results that carbon flowing into the microbial loop through the mediation of enzymatic degradation of extracellular products in a benthic system exceeds that in the overlying water column.

Treatment of acute stanford type B aortic dissection with a novel cylindrical balloon catheter in dogs

BACKGROUND

Despite recent progress in medical and surgical treatment, acute type B aortic dissection still carries a high mortality rate. We have developed a novel cylindrical balloon catheter for less invasive treatment to block the entry of the dissection and induce thrombotic occlusion of the false lumen. The balloon has the shape of a sheet when deflated but a double-cylinder shape when inflated. Therefore, aortic blood flow is maintained through the cylindrical lumen during balloon inflation.

METHODS AND RESULTS

Six beagle dogs underwent a left thoracotomy at the 6th intercostal space. An acute dissection of 4-cm length was created surgically on the descending aorta. The balloon catheter was inserted through the distal descending aorta and advanced to the entry site. The balloon catheter was inflated for 6 hours. The blood flow in the descending aorta and the position of the balloon was monitored by color Doppler echovasculography. Four dogs were killed humanely on the following day and 2 dogs 10 days after the surgery. The descending aorta was examined macroscopically and microscopically in all dogs. In all dogs, the false lumen was occluded by thrombi. Although no dog had clinical evidence of distal thromboembolism, 2 of the 4 dogs that were killed on the second postoperative day had fresh mural thrombi in the true lumen.

CONCLUSIONS

The false lumen of the acute type B aortic dissection was effectively occluded by the novel cylindrical balloon catheter in the canine experimental model. The thrombus formation in the true lumen is the problem to be solved.

Articulatory function in patients who have undergone glossectomy with use of an artificial graft membrane

OBJECTIVE

The purpose of this study was to investigate, by assessing speech intelligibility, the long-term usefulness of an artificial bilayer membrane as a mucosal substitute after glossectomy.

STUDY DESIGN

Artificial membranes were grafted in 8 patients with intraoral defects after glossectomy. Five patients served as a control group and received only standard closure by suture after glossectomy. Speech intelligibility was evaluated by means of a standardized Japanese speech intelligibility test 6 months or more after the operation.

RESULTS

The postoperative courses of all 13 patients were uneventful. Intelligibility scores of those who received grafts were better than those of the control group in the overall score, the glossal sounds score, and the rear portion sounds score.

CONCLUSION

The artificial membrane was useful for the glossectomy as a long-term mucosal substitute, as well as for the short-term.

Accuracy of integration of dental casts in three-dimensional models

PURPOSE

This study investigated errors occurring in three-dimensional (3D) models when plaster dental casts are integrated into them.

MATERIALS AND METHODS

Three-dimensional milling models of three patients with a jaw deformity were fabricated using the Endoplan system (SPARC International Inc, Santa Clara, CA). After this, plaster dental casts were integrated into the 3D models using a face-bow transfer system. Two cephalograms were then compared, one obtained from the patient and the other obtained from the 3D model painted with contrast medium.

RESULTS

In two cases, the reproducibility of the dental position as determined by angle analysis was within 2 degrees, and that determined by distance analysis was within 2 mm. However, errors over 4 degrees and 4.2 mm, respectively, were observed in one case.

CONCLUSION

It is clinically important to confirm the accuracy of the 3D model by cephalometric analysis, and it may be necessary to reposition the dental model based on the results.

Autolysis of lentinan, an antitumor polysaccharide, during storage of Lentinus edodes, shiitake mushroom

The lentinan contents in the Lentinus edodes fruit body during storage were examined by ELISA method using anti-lentinan antibodies. The lentinan content (12.8 mg.g(-)(1) dw) before storage decreased to 3.7 mg.g(-)(1) dw over 7 days at 20 degrees C. However, it only slightly decreased at 1 degrees C and only decreased to 9.3 mg. g(-)(1) dw at 5 degrees C. Glucanase activity, which seems to be associated with lentinan degradation, increased more during storage of L. edodes at 20 degrees C than it did at lower temperatures. In addition, only glucose was detected as a degraded product from lentinan by the glucanase. This suggested that this enzyme would fit the profile of an exo-type glucanase. Also, polyphenol oxidase activity, known as an index of freshness reduction in the mushroom, increased approximately 2.7-fold (to 61.5 units.mg(-)(1)) over 7 days during storage at 20 degrees C. However, its activity changed little during storage at lower temperatures. These results indicate that the reduction during storage of the quality of L. edodes as a functional food is accompanied by the decrease of lentinan, and by browning, and that exo-glucanase plays an important role in the decrease of lentinan content.

Anti-tumor polysaccharide from the mycelium of liquid-cultured Agaricus blazei mill

Anti-tumor active polysaccharide against Sarcoma 180 was isolated by DEAE-Sepharose CL-6B and Sepharose 4B column chromatography from the hot-water soluble fraction of the mycelium of liquid-cultured Agaricus blazei mill. This polysaccharide did not react with antibodies of anti-tumor polysaccharides such as lentinan, gliforan, and FIII-2-b which is one of anti-tumor polysaccharides from Agaricus blazei. Moreover, the analyses of 13C-NMR and GC-MS suggested that this polysaccharide was preliminarily glucomannan with a main chain of beta-1,2-linked D-mannopyranosyl residues and beta-D-glucopyranosyl-3-O-beta-D-glucopyranosyl residues as a side chain. This polysaccharide was completely different from the anti-tumor polysaccharide from fruiting body of Agaricus blazei, beta-1,6-glucan.

[Pheochromocytoma of the left retroperitoneal paraganglion associated with torsade de pointes: a case report]

A 54-year-old woman developed torsade de pointes with secondary QT prolongation due to hypokalemia and hypomagnesemia. Her serum K and Mg levels were 2.5 mEq/l and 1.5 mg/dl, respectively. This electrolyte imbalance was due to intentional overdosing of metolazone. Attacks of torsade de pointes occurred three times in the intensive care unit and were corrected by intravenous lidocaine administration. Her serum K level was corrected using KCl infusion, restoring the normal QT interval. Routine computed tomography found a left retroperitoneal paraganglioma. Urinary and serum catecholamine examination revealed extremely high values of epinephrine and norepinephrine. The diagnosis was pheochromocytoma in the left retroperitoneal paraganglion. The tumor which was removed measured 70 x 65 x 60 mm in size. Microscopic examination revealed the characteristic patterns of pheochromocytoma.

[Primary right atrial hemangiosarcoma manifesting as cardiac tamponade: a case report with transesophageal echocardiography]

A 39-year-old woman presented with a right atrial hemangiosarcoma manifesting as cardiac tamponade with complaints of chest discomfort and dyspnea. Transthoracic echocardiography revealed remarkable pericardial effusion and a right atrial mass. Transesophageal echocardiography disclosed the tumor extending into the right atrial cavity. Surgery found the tumor was poorly demarcated, immobile and adhered to the adjacent right atrial wall and septum. The echocardiographic findings correlated well with the surgical and autopsy findings.

[A case of aortic bicuspid valvular endocarditis with congenital left ventricular diverticulum]

A 29-year-old man had a prolonged fever and painful Osler's nodes on his right foot. The aortic valve was bicuspid with vegetation mass and the left ventricular diverticulum was additionally present connecting with the left ventricular outflow tract. An operation was performed after intravenous administration of antibiotics for 3 weeks. The aortic bicuspid valve and the vegetation were removed and replaced by an artificial valve (SJM-HP 19 mm). The left ventricular diverticulum was resected. The echocardiographic findings correlated well with the intraoperative observation.

New surgical technique for repair of ventricular septal perforation

We describe a technique for repairing the ventricular septal perforation using porcine pericardium tailored in a conical shape. This technique may allow a good operating view and facilitate suturing to the left ventricular cavity.

[Two cases of surgically treated malignant primary tumors originated from the pulmonary artery]

Two surgically treated cases of malignant tumors which originated inside of the pulmonary artery were reported. A 62-year-old female with an undifferentiated sarcoma and a 24-year-old male with a malignant fibrous histiocytoma were successively operated on in two months for the release of their chief complaints of exertional dyspnea. In the first case the tumor was resected completely, although partially resected in the second case. Preoperatively, noninvasive examinations including the echocardiography, the computed tomography and the magnetic resonance imaging confirmed the presence of these tumors in the main pulmonary arteries in both cases and also the invasion to the vessel wall with the growth to the pericardial cavity in the second case. Both patients are doing well and has been followed up at the out-patient department 22 and 20 months after surgery, respectively.

[A case of left ventricular-right atrial communication complicated with aortic regurgitation caused by active infective endocarditis]

A 63-year-old man with cough and shortness of breath was diagnosed to have active infective endocarditis resulting in acute pulmonary edema with aortic regurgitation caused by a huge vegetation on the noncoronary cusp and left ventricular-right atrial (LV-RA) communication which were demonstrated by the echocardiogram and color doppler method. The LV-RA communication located at the atrioventricular portion of the membranous septum was closed with GoreTex patch through the right atrium combined with the aortic valve replacement with a bileaflet mechanical valve in emergency. The bacteriological studies demonstrated staphylococcus epidermidis. The postoperative course was uneventful and the patient is now on regular duty two years after surgery.

[Study of pulmonary function after CABG with pleurotomy]

We studied the influence of pleurotomy during harvesting IMA for CABG on postoperative pulmonary function. Ninety nine cases underwent CABG surgery from January 1991 to July 1992, were divided into three subgroups, 45 patients (subgroup AY 2) having bilateral IMAs graft with pleurotomy, 45 patients (subgroup AY 1) having unilateral IMA graft with pleurotomy, 9 patients (subgroup AN) having unilateral IMA graft or vein grafts without pleurotomy. Frequencies of chest X-rays abnormality such as elevation of diaphragm and accumulation of pleural effusion before discharge around 2 weeks after surgery, were not significantly different among three subgroups. 58 cases without chest X-rays abnormalities were divided into three subgroups in the same way. There was no case with late extubation or with postoperative pulmonary complication. At first we compared pre-with postoperative pulmonary function in each subgroups. Pulmonary function (VC, FEV1.0, peak flow, MMF, V50, V25) was significantly deteriorated in the patients with pleurotomy, while VC, FEV1.0, peak flow significantly decreased, and MMF, V50 and V25 tended to decrease in the patients without pleurotomy. Moreover, magnitude of change of pulmonary function from pre- to postoperative period were not different significantly among three subgroups. In conclusions pleurotomy itself didn't appear to influence postoperative morbidity.