Highly Stable Polymer Coating on Silver Nanoparticles for Efficient Plasmonic Enhancement of Fluorescence

Surface coating of plasmonic nanoparticles is of huge importance to suppress fluorescence quenching in plasmon-enhanced fluorescence sensing. Herein, a one-pot method for synthesizing polymer-coated silver nanoparticles was developed using a functional polymer conjugated with disulfide-containing anchoring groups. The disulfides played a crucial role in covalently bonding polymers to the surface of the silver nanoparticles. The covalent bond enabled the polymer layer to form a long-term stable coating on the silver nanoparticles. The polymer layer coated was adequately thin to efficiently achieve plasmonic enhancement of fluorescence and also thick enough to effectively suppress quenching of fluorescence, achieving a huge net enhancement of fluorescence. The polymer-coated plasmonic nanoparticles are a promising platform for demonstrating highly sensitive biosensing for medical diagnostics.

Ultrastructural and immunohistochemical studies on myocardial biopsies from a patient with eosinophilic endomyocarditis

Right ventricular endomyocardial biopsy specimens from a 13-year-old boy with hypereosinophilia were studied by light and electron microscopy using the EG2 monoclonal antibody, which recognizes a common epitope of eosinophil cationic protein and eosinophil protein-X. Although the endocardial layer was of normal thickness, many eosinophils, mononuclear cells, and free eosinophil granules were observed in the endocardium and in the vicinity of degenerated myocardial cells. Under electron microscopy, many of the specific granules in and out of eosinophils had lost their crystalloid internae and displayed reversed density, and there were many degranulated eosinophils with reduced number of granules. Immunohistochemically, large amounts of eosinophil cationic protein and protein-X were observed within cardiocytes when many of them were degenerated. Deposits of the proteins were also found in some small vessels. On electron microscopy, accumulations of gold particles, which bind to eosinophil cationic protein and protein-X, were seen in association with specific granules and on the myofilaments in both degenerated and normal-appearing cardiocytes. The presence of eosinophil cationic proteins within cardiocytes may play an important role in the pathogenesis of eosinophilic endomyocardial disease.

Influence of cycloplegia with topical cyclopentolate on higher-order aberrations in myopic children

PURPOSE

To investigate the influence of cycloplegia with topical cyclopentolate on wavefront aberrations in myopic children.

DESIGN

This is a prospective, comparative study.

METHODS

Twenty-eight myopic children with a mean age of 7.25 ± 2.55 were enrolled in this study. We evaluated refraction and wavefront aberrations before and after cycloplegia with 1% cyclopentolate hydrochloride. Ocular and corneal aberrations were simultaneously measured and compared with each other. Individual Zernike components were also analyzed up to the sixth order. All these parameters were compared before and after cycloplegia.

RESULTS

Ocular higher-order aberrations (HOAs) significantly increased after cycloplegia (P=0.012 for spherical-like and P=0.015 for total HOAs). Corneal HOAs did not change after cycloplegia. When corneal and ocular HOAs were compared, the ocular HOAs were significantly smaller than the corneal HOAs in spherical-like aberrations (P<0.001) and total HOAs (P=0.006). As for individual Zernike components, ocular aberration generally showed smaller or equivalent values in comparison with corneal aberration. In addition, each Zernike component showed a large standard deviation.

CONCLUSIONS

Internal optics compensates for corneal HOAs in myopic children, and paralysis of tonic accommodation with cyclopentolate considerably affects ocular HOAs. However, inter-individual variation in each Zernike component is quite large in myopic children.

Time course of changes in ocular wavefront aberration after administration of eye ointment

PURPOSE

To investigate the influence of an eye ointment on ocular aberration.

DESIGN

Prospective, comparative study.

METHODS

In 10 normal volunteers, ocular aberration was assessed before and 5, 30 min, 1, 2, 3, 6, and 12 h after administration of ofloxacin eye ointment. Ocular aberration was sequentially measured over a period of 10 s, and the root mean square (RMS) of the second-, third-, fourth-, and total higher-order aberrations (HOAs) were determined. From the sequential changes in total HOAs during 10 s, the fluctuation index (FI) and stability index (SI) were calculated. The obtained data were compared with those of another 17 normal volunteers who received timolol maleate gel-forming ophthalmic solution.

RESULTS

No significant changes in second-order RMS were observed after administration of the ointment. HOAs such as third-, fourth-, and total higher-order RMS significantly changed during the study period (P<0.05, repeated-measures analysis of variance). The RMS of each HOA component significantly increased 5 min after administration compared with the baseline values (P<0.05, Dunnett test). FI also increased significantly 5 min after administration (P<0.05), but SI did not change significantly. When compared with the results of the gel-forming solution group, HOAs and FI showed significantly higher values at several time points during 6 h after application (P<0.05, Mann-Whitney U-test).

CONCLUSIONS

Administration of eye ointment significantly degrades optical quality of the eye by increasing and oscillating HOAs. These changes were more pronounced than those after instillation of gel-forming ophthalmic solution for at least several hours.

Avaliação quantitativa da contaminação por micro-organismos no ambiente de criação do bicho-da-seda (Bombyx mori L.) na fase de chocadeira

O objetivo do presente trabalho foi avaliar a contaminação bacteriana e fúngica em chocadeira antes e após procedimento de limpeza e desinfecção. Foram coletadas amostras do ar e de superfícies do piso, da parede, das folhas de amoreira, das lagartas do bicho-da-seda e da máquina picadeira de folhas. A metodologia empregada seguiu a técnica da placa de sedimentação e contato de superfície com meios de cultura específicos, Ágar Nutriente, Ágar McConkey e Ágar Sabouraud Dextrose para crescimento, respectivamente, de bactérias, de enterobactérias e de fungos. Os resultados demonstraram, ao término dos dois primeiros ínstars, aumento nos índices de contaminação fúngica e bacteriana nas superfícies das lagartas do bicho-da-seda, do piso e das folhas de amoreira. A limpeza e desinfecção reduziram o grau de contaminação por micro-organismos presentes no ambiente, do nível péssimo para o excelente. As folhas de amoreira representaram um forte potencial de infecção para as lagartas do bicho-da-seda. A contagem de colônias fúngicas e bacterianas foi uma forma simples de monitorar e detectar os pontos de problemas sanitários da chocadeira.

Recovery of corneal irregular astigmatism, ocular higher-order aberrations, and contrast sensitivity after discontinuation of overnight orthokeratology

AIMS

To examine prospectively the recovery of various parameters after discontinuation of overnight orthokeratology.

METHODS

Seventeen subjects undergoing orthokeratology for 12 months were examined. Refraction, corneal topography, wavefront aberrometry, a visual acuity test and a contrast sensitivity test were performed at baseline, 12 months after commencement of the procedure, and 1 week and 1 month after discontinuation of the treatment. Asymmetry and higher-order irregularity components were calculated using a Fourier analysis of the corneal topography data. Contrast sensitivity was assessed at four spatial frequencies, and the area under the log contrast sensitivity function (AULCSF) was calculated.

RESULTS

Orthokeratology significantly reduced manifest refraction (p<0.0001, Dunnett test) and significantly improved uncorrected visual acuity (UCVA) at 12 months after commencement of the procedure (p<0.0001). Asymmetry and higher-order irregularity components increased significantly (p<0.0001, p = 0.0032, respectively), and third- and fourth-order aberrations also increased significantly (p<0.0001). The treatment resulted in significant decreases in AULCSF (p = 0.0004). After discontinuing lens wear, all parameters, such as refraction, UCVA, asymmetry, higher-order irregularity, third-order aberration, fourth-order aberration and AULCSF, returned to the baseline level at 1 week.

CONCLUSION

This study confirmed that the effect of orthokeratology is completely reversible in light of optical quality of the eye and quality of vision as well as refraction and visual acuity.

Higher-order wavefront aberration and letter-contrast sensitivity in keratoconus

AIMS

To evaluate the relation between higher-order aberration of the eye and contrast sensitivity function in eyes with keratoconus.

METHODS

In 22 eyes of 14 patients with keratoconus (age 30.5+/-8.4 years, means+/-SD) and 26 eyes of 13 normal controls (age 29.2+/-6.7 years), ocular higher-order wavefront aberration for a 6-mm pupil was measured with the Hartmann-Schack aberrometer (KR-9000 PW, Topcon). The root mean square (RMS) of third- and fourth-order Zernike coefficients was used to represent higher-order aberrations. The letter-contrast sensitivity was examined using the CSV-1000LV contrast chart (Vector Vision).

RESULTS

In the keratoconus group, the letter-contrast sensitivity showed significant correlation with third-order (Spearman's correlation coefficient r=-0.736, P<0.001) and fourth-order aberrations (r=-0.464, P<0.05). There was borderline correlation between log MAR BSCVA and third-order (r=0.413, P=0.070) and fourth-order aberrations (r=0.394, P=0.086). In the normal group, the letter-contrast sensitivity had no significant correlation with third-order (r=-0.170, P=0.411) and fourth-order aberrations (r=-0.088, P=0.673), and log MAR best spectacle-corrected visual acuity (BSCVA) showed no correlation with third-order (r=0.063, P=0.762) and fourth-order aberrations (r=-0.282, P=0.165).

CONCLUSIONS

In eyes with keratoconus, there is significant correlation between contrast sensitivity and ocular higher-order wavefront aberrations.

Retention and removal of a new viscous dispersive ophthalmic viscosurgical device during cataract surgery in animal eyes

AIMS

To assess the retention and removal properties of a new viscous dispersive ophthalmic viscosurgical device (OVD), DisCoVisc, in comparison with those of cohesive (Provisc), dispersive (Viscoat), and viscoadaptive (Healon5) OVDs.

METHODS

In 20 porcine eyes, cataract surgery was simulated using one of the four OVDs which were stained with fluorescein for better visualisation. Three parameters were measured. Firstly, the presence/absence of OVDs in the chamber at the completion of phacoemulsification was recorded. Secondly, the time until the OVDs were completely removed from the anterior chamber using the phaco needle was measured. Thirdly, after intraocular lens (IOL) implantation, the time needed to completely remove the OVDs from the chamber with irrigation/aspiration tip was recorded.

RESULTS

At the completion of phacoemulsification, the OVDs retained in 0% (0/5) for Provisc, 80% (4/5) for Healon5, 100% (5/5) for DisCoVisc, and 100% (5/5) for Viscoat. The retention of OVDs during phacoemulsification was greatest with Viscoat followed by, in descending order, DisCoVisc, Healon5, and Provisc. The removal of OVDs after IOL implantation took longest with Viscoat followed by Healon5, DisCoVisc, and Provisc.

CONCLUSION

The viscous dispersive DisCoVisc showed excellent retention during phacoemulsification, while its removal after IOL implantation was very easy. When compared with the viscoadaptive Healon5, DisCoVisc was retained better in the chamber and was easier to remove. These features of DisCoVisc should be highly advantageous when considering covering the entire cataract surgery procedure with a single OVD.

AVALIAÇÃO BIOLÓGICA E PRODUTIVA DO BICHO-DA-SEDA (BOMBYX MORI L.) ALIMENTADO COM FOLHAS DE AMOREIRA PULVERIZADAS COM EXTRATO DE MIRABILIS JALAPA

RESUMO O presente estudo foi realizado na Unidade de Pesquisa e Desenvolvimento de Gália, Pólo Regional de Desenvolvimento Tecnológico dos Agronegócios do Centro Oeste, em 2004, com o objetivo de avaliar a biologia e produção do bicho-da-seda quando exposto ao extrato de Mirabilis jalapa (família: Nyctaginaceae). Esse trabalho foi baseado em estudos prévios, em condições de laboratório, que mostraram a ação do extrato aquoso de Mirabilis jalapa, na concentração de 10%, sobre o controle do vírus da poliedrose (NPVBm), conferindo 100% de proteção ao inseto. Em condições de criação comercial, o extrato foi empregado nas diferentes fases larvais do inseto. Tanto em condições de laboratório como em condições de criação comercial o extrato não causou alterações na biologia e produção do bicho-da-seda, quando comparado com grupos não tratados. Embora os insetos estivessem infectados com NPVBm, não foram observados sintomas de infecção, sugerindo que a população viral, apesar de presente, foi mantida em níveis reduzidos não afetando o desempenho produtivo. Não foi observada uma ação anticontaminante do extrato contra outros patógenos oportunistas, uma vez que foram boas as condições sanitárias de criação, ocorrendo poucas mortes, provavelmente relacionadas mais com fatores naturais do que com a ocorrência de doenças.

Importance of early repair of isolated abdominal aortic dissecting aneurysm

BACKGROUND

Since the available information on isolated abdominal aortic dissecting aneurysm (AADA) is mainly related to case reports or reports of small groups of patients, its natural history remains undetermined and there is no agreement on its optimal management. The purpose of this study is to define the features and pattern of development of this unusual entity as well as to propose criteria for treatment based on our own experience and previously published data.

PATIENTS AND METHODS

We retrospectively evaluated the history of 6 patients diagnosed with AADA. The patients were 5 males and 1 female. The mean age was 71 +/- 8 years (range: 61-80 years), and the mean aneurysm diameter was 54 +/- 14 mm (range: 35-70 mm). All of these patients were hypertensive (100%). History of cerebrovascular accident, ischemic heart disease, peripheral arterial disease, or diabetes mellitus was present in 1 patient, respectively. Two patients developed mycotic AADA.

RESULTS

Emergency operations had been performed in 3 cases, and scheduled surgical reconstruction in the remaining 3 cases. Operation consisted of aneurysmectomy and graft replacement of the diseased aortic segment in all cases. One patient treated in an emergency setting died subsequently of multisystem organ failure, but the others did well.

CONCLUSION

Symptomatic patients or patients at good risk should undergo surgical repair earlier than in the case of abdominal aortic aneurysm without dissection (AAA). Dissection in addition to an AAA will further increase the weakness of the aortic wall and the possibility of aortic rupture will become higher.

Comparison of corneal thickness measurements using Orbscan II, non-contact specular microscopy, and ultrasonic pachymetry in eyes after laser in situ keratomileusis

AIMS

To compare central corneal thickness measurements of three pachymetry devices in eyes after laser in situ keratomileusis (LASIK).

METHODS

Central corneal thickness was measured in 203 eyes after myopic LASIK. Orbscan II scanning slit topography (Bausch & Lomb), SP-2000P non-contact specular microscopy (Topcon), and ultrasonic pachymetry (Tomey) were used in this sequence.

RESULTS

Three devices gave significantly different corneal thickness readings (p<0.0001, repeated measure analysis of variance). The measurements of Orbscan II (445.6 (SD 60.0) microm) were significantly smaller than those of noncontact specular microscopy (467.9 (SD 40.2) micro m; p<0.0001, Tukey multiple comparison) and ultrasonic pachymetry (478.8 (SD 41.9) microm; p<0.0001). The value obtained with SP-2000P non-contact specular microscopy was significantly smaller than that taken with ultrasonic pachymetry (p<0.001). There were significant linear correlations between scanning slit topography and non-contact specular microscopy (Pearson's correlation coefficient r = 0.912, p<0.0001), non-contact specular microscopy and ultrasonic pachymetry (r = 0.968, p<0.0001), and ultrasonic pachymetry and scanning slit topography (r = 0.933, p<0.0001).

CONCLUSION

In post-LASIK eyes, Orbscan II scanning slit topography significantly underestimated corneal thickness. Non-contact specular microscopy gave smaller thickness readings than ultrasonic pachymetry, but these two units showed an excellent linear correlation.

Condensation reaction of hexanucleotides containing guanine and cytosine with water soluble carbodiimide

The condensation reactions of hexanucleotides involving guanine and cytosine in the presence of water-soluble carbodiimide (WSC) have been investigated as a model reaction of the prebiotic formation of RNA under primitive earth. The reactions formed cyclic hexanucleotides and dimers in which the product yields were dependent on the sequence.

[Assessment of saphenous vein grafts flow by Doppler echocardiography]

In an effort to evaluate flow characteristics of the saphenous vein grafts (SVG) after coronary artery bypass grafting, we performed duplex scanning of SVG which were anastomosed to the left anterior descending artery in 12 patients, and compared those indexes with 34 internal thoracic artery grafts (ITAG). The SVG were observed with a 7.5 MHz duplex scanner through the anterior intercostal space. The diameter of the vessel, systolic peak velocity, and diastolic peak velocity were recorded in both groups, and systolic flow volume, diastolic flow volume, and velocity ratio were calculated. The systolic and diastolic peak velocity of SVG were predominantly lower than ITAG. No difference in the diameter and flow ratio could not be demonstrated between 2 groups. The flow volume of SVG were also predominantly lower than that of ITAG throughout cardiac cycle. This study reveals that advanced stenotic change were caused in the SVG group and suggest the occurrence of vein grafts disease long after coronary artery bypass grafting.

Mirror image myopic anisometropia in two pairs of monozygotic twins

Two sets of monozygotic twins with mirror image myopic anisometropia are reported. The first set were two boys aged 1 year 8 months. There was a right eye myopic anisometropia in one twin, and a left eye myopic anisometropia in the other. The differences in refractive power between both eyes were 11.6 and 7.6 dpt, respectively (spherical equivalent). The second set were two 6-year-old boys. The right eye had myopic anisometropia in one twin, while the left eye was affected in the other. The differences in refractive power between both eyes were 6.5 and 3.7 dpt, respectively (spherical equivalent). Exotropia was recognized in 3 cases. Previously only two sets of monozygotic twins with mirror image myopic anisometropia have been reported. Monozygotic twins with mirror image myopic anisometropia are extremely rare.

Genistein, a soybean isoflavone, inhibits inward rectifier K(+) channels in rat osteoclasts

Genistein, a soybean-derived isoflavone with an inhibitory effect on protein tyrosine kinases (PTKs), has been shown to suppress osteoclastic bone resorption. To clarify the mechanisms underlying this action, we investigated the effects of genistein on inward rectifier K(+) current (I(Kir)) in rat osteoclasts by using the whole-cell patch-clamp technique. Extracellularly applied genistein inhibited I(Kir) in a concentration-dependent manner. Physiologically attainable concentrations of genistein inhibited I(Kir). IC(50) values obtained 5 and 10 min after the application of genistein were 54 and 27 microM, respectively. The removal of genistein partially restored the current. Daidzein, an isoflavone without PTK-inhibiting activity, also showed a weak inhibitory effect on I(Kir), but genistin had no effect. Other PTK inhibitors, tyrphostin A25, tyrphostin B42, and tyrphostin B46, inhibited I(Kir), whereas herbimycin A and lavendustin A were without effect. The inactive tyrphostin, A1, showed a similar inhibitory effect as tyrphostin A25. The tyrosine phosphatase inhibitor, orthovanadate, did not affect the inhibitory potency of genistein on I(Kir). The inhibitory action of genistein was unaffected by changing intracellular Ca(2+) concentration ([Ca(2+)]i) or by pretreatment of the cell with GDPbetaS, Rp-cAMPS, okadaic acid, or staurosporine. Therefore the inhibition of I(Kir) by genistein does not depend on PTK inhibition, involvement of changes in [Ca(2+)]i, or secondary interaction with protein kinase A or protein kinase C. Genistein-induced inhibition of I(Kir) would cause membrane depolarization, elevation of [Ca(2+)]i, and inhibition of osteoclastic bone resorption.

[Assessment of left internal thoracic artery graft by exercise Doppler echocardiography]

Doppler echocardiography has several advantages such as frequent use, noninvasive approach, and physiological evaluation. Supine bicycle exercise testing was conducted for 30 patients undergoing CABG with LITA to LAD. Doppler echocardiography studies were performed before and after exercise to observe the change. On the basis of the angiographic data, patients were divided into two groups: 27 patients with a patent LITA graft, 3 patients with mildly stenosed LITA graft. In the patients who had patent grafts, diastolic flow velocity were increased higher than systolic after exercise. In the stenotic group, the flow pattern was changed to further systolic one. Doppler echocardiography during exercise is thought to be a reliable method to assess the LITA flow.

Defect in human myocardial long-chain fatty acid uptake is caused by FAT/CD36 mutations

Because of the importance of long-chain fatty acids (LCFAs) as a myocardial energy substrate, myocardial LCFA metabolism has been of particular interest for the understanding of cardiac pathophysiology. Recently, by using radiolabeled LCFA analogues, myocardial LCFA metabolism has been clinically evaluated, which revealed a total defect of myocardial LCFA accumulation in a small number of subjects. The mechanism for the cellular LCFA uptake process is still disputable, but recent results suggest that fatty acid translocase (FAT)/CD36 is a transporter in the heart. In the present study, we analyzed mutations and protein expression of the FAT/CD36 gene in 47 patients who showed total lack of the accumulation of a radiolabeled LCFA analogue in the heart. All the patients carried two mutations in the FAT/CD36 gene, and expression of the FAT/CD36 protein was not detected on either platelet or monocyte membranes. Our results showed the link between mutations of the FAT/CD36 gene and a defect in the accumulation of LCFAs in the human heart.

Factors associated with increased aqueous flare in psoriasis

PURPOSE

To evaluate the changes in aqueous flare in psoriasis patients and to identify the factors that influence the level of aqueous flare.

METHODS

We examined the 68 eyes of 34 psoriasis patients and the 68 eyes of 34 healthy subjects with a laser flare-cell meter. Complete dermatologic and ophthalmic examinations were performed on the psoriasis patients.

RESULTS

Flare was significantly higher in psoriasis patients than in normal controls (P <.000l). The factors that increased flare significantly were age and Psoriasis Area and Severity Index. Flare was not significantly associated with sex, psoriasis type, duration of disease, and cyclosporin therapy. A flare increase was significantly correlated with serum total protein and immunoglobulin (Ig) A, but not with albumin, IgG, and IgM.

CONCLUSIONS

Psoriasis patients, even without ocular symptoms, had slight damage to the blood-aqueous barrier. Multiple linear regression analysis showed that flare had the strongest correlation with the severity of psoriasis.

[A case of lateral origin of the left internal mammary artery]

A 66 years old men, with left anterior descending coronary artery (LAD) stenosis and aortic valve stenosis, underwent coronary artery bypass grafting (CABG) to LAD with left internal mammary artery (LIMA) and aortic valve replacement. His postoperative course was uneventful. But, postoperative angiogram showed that his patent LIMA graft was originated from much lateral side of the left subclavian artery. Internal mammary artery is considered the most ideal graft for CABG, but its' anomality is not well known. We present this rare case with the anomalous origin of LIMA.

Refractive changes in diabetic patients during intensive glycaemic control

AIMS

To evaluate the clinical course and the characteristics of transient refractive error occurring during intensive glycaemic control of severe hyperglycaemia.

METHODS

28 eyes of patients with persistent diabetes were included in this prospective study. During the observation period, patients underwent general ophthalmological examination and A-mode scan ultrasonography was performed at each examination-at days 1, 3, and 7, and then once every week or every other week until recovery of hyperopia.

RESULTS

A transient hyperopic change occurred in all patients receiving improved control after hyperglycaemia. Hyperopic change developed a mean of 3.4 (SD 2. 0) days after the onset of treatment, and reached a peak at 10.3 (6. 1) days, where the maximum hyperopic change in an eye was 1.47 (0. 87) D (range 0.50-3.75 D). Recovery of the previous refraction occurred between 14 and 84 days after the initial assessment. There was a positive correlation between the magnitude of the maximum hyperopic change and (1) the plasma glucose concentration on admission (p<0.01), (2) the HbA(1c) level on admission (p<0.005), (3) the daily rate of plasma glucose reduction over the first 7 days of treatment (p<0.001), (4) the number of days required for hyperopia to reach its peak (p<0.001), and (5) the number of days required for the development and resolution of hyperopic changes (p<0.0001). There was a negative correlation between the maximum hyperopic change of an eye and baseline value of refraction (p<0.01). During transient hyperopia, no significant changes were observed in the radius of the anterior corneal curvature, axial length, lens thickness, or depth of anterior chamber.

CONCLUSIONS

The degree of transient hyperopia associated with rapid correction of hyperglycaemia is highly dependent on the rate of reduction of the plasma glucose level. A reduction of refractive index in intraocular tissues, especially in lens, appears to be responsible for this hyperopic change.

[A case of ascending aortic aneurysm with intrathoracic goiter]

A case of the successful operation for ascending aortic aneurysm and intrathoracic goiter was described. A 71-year-old woman was admitted to our hospital for the treatment of ascending aortic aneurysm disclosed by the examination in another hospital. Preoperative chest CT showed ascending aortic aneurysm as large as 8 cm in diameter, and an upper mediastinal tumor compressing the main bronchus. The tumor was continuous with the right lobe of the thyroid. The excision of the tumor was performed through median sternotomy with cervical collar incison. After that, the replacement of the ascending aorta was carried out under cardiopulmonary bypass and hypothermic circulatory arrest. The histological examination of the resected specimen revealed adenomatous goiter without malignancy.

Estrogen directly acts on osteoclasts via inhibition of inward rectifier K+ channels

Using the whole-cell patch-clamp technique in freshly isolated rat osteoclasts we examined the effects of estrogen on ionic channels. The predominant current was an inward rectifier K+ current (IKir). In the absence of non-osteoclastic cells, extracellularly applied 17beta-estradiol (>0.1 microM) inhibited IKir, indicating that estrogen acts directly on osteoclasts. Application of 17beta-estradiol (10 microM) for 10 min reduced IKir at the membrane potential of -120 mV to 70 +/- 15% of control. Removal of 17beta-estradiol partially restored the inhibition. The inhibition of IKir was dependent on concentration and application time. Intracellularly applied 17beta-estradiol had no effect on IKir. 17alpha-estradiol also inhibited the IKir, whereas progesterone and testosterone had no effect. The inhibitory action of 17beta-estradiol was not affected by guanosine 5'-O-(2-thiodiphosphate) (GDPbetaS), adenosine 3',5'-cyclic monophosphothioate Rp diastereomer (Rp-cAMPS), okadaic acid, staurosporine and phorbol ester, and was independent of intracellular Ca2+ concentration ([Ca2+]i). With no influence from soluble factors secreted from non-osteoclastic cells, preincubation of the osteoclasts for more than 60 min with much lower concentrations of 17beta-estradiol (1 and 10 nM) caused a reduction of IKir. In current-clamp configuration, application of 17beta-estradiol (10 microM) depolarized the membrane associated with a decrease in a membrane conductance, indicating that 17beta-estradiol inhibits IKir and depolarizes the membrane of osteoclasts. These results suggest that the 17beta-estradiol-induced inhibition of IKir might be mediated via non-genomic mechanisms. This direct action of 17beta-estradiol on osteoclasts may contribute to the regulation of [Ca2+]i and partially account for the protective effects of estrogen against bone loss.

Protein tyrosine kinase inhibitors increase cytosolic calcium and inhibit actin organization as resorbing activity in rat osteoclasts

Although there is evidence that protein tyrosine kinase inhibitors (PTKIs) suppress bone resorption activity, the mechanism of action of these compounds on osteoclastic bone resorption remains obscure. In the present study, we investigated the effect of PTKIs on cytosolic Ca(2+) concentration ([Ca(2+)](i)) and on the cytoskeleton in rat osteoclasts. The PTKIs, genistein and herbimycin A, reversibly elevated [Ca(2+)](i) measured by fura-2 microfluorimetry. The PTKI-induced increase was abolished by omission of extracellular Ca(2+), but was not attenuated by depletion of Ca(2+) stores. The PTKI-induced increase was inhibited by addition of La(3+) and Ni(2+), but not abolished by dihydropyridine (DHP) Ca(2+) channel blockers. Genistin, an inactive analogue of genistein, had no effect on [Ca(2+)](i). In the cytoskeleton assay, genistein rapidly disrupted the actin ring formation that serves as a marker for the resorbing state of osteoclasts. Disruption of the actin ring formation was also diminished in Ca(2+)-free extracellular solution. These results suggest that PTKIs in rat osteoclasts elevate [Ca(2+)](i) via activation of a DHP-insensitive, nonspecific Ca(2+) entry pathway and disrupt the formation of actin rings, resulting in suppression of bone resorption activity. The regulation of this Ca(2+)-influx by PTKIs is likely to contribute to inhibition of bone resorption by these compounds.

Human heart-type cytoplasmic fatty acid-binding protein (H-FABP) for the diagnosis of acute myocardial infarction. Clinical evaluation of H-FABP in comparison with myoglobin and creatine kinase isoenzyme MB

Heart-type fatty acid-binding protein (H-FABP) is a low molecular weight cytoplasmic protein and present abundantly in the myocardium. When the myocardium is injured, as in the case of myocardial infarction, low molecular weight cytoplasmic proteins including H-FABP are released into the circulation and H-FABP is detectable in a blood sample. We have already developed a direct sandwich-ELISA for quantification of human H-FABP using two distinct types of monoclonal antibodies specific for human H-FABP. In this study we investigated the clinical validity of H-FABP as a biochemical diagnostic marker in the early phase of acute myocardial infarction (AMI). To evaluate the diagnostic usefulness of H-FABP in the early phase of AMI, blood samples were obtained from the following patients within 12 hours after the appearance of symptoms, and serum levels of H-FABP were compared with those of conventional diagnostic markers, such as myoglobin and creatine kinase isoenzyme MB (CK-MB). Blood samples were collected from patients with confirmed AMI (n=140), patients with chest pain who were afterwards not classified as AMI by normal CK-MB levels (non-AMI) (n=49) and normal healthy volunteers (n=75). The serum concentration of H-FABP was quantified with our direct sandwich-ELISA. The concentration of myoglobin mass was measured with a commercial RIA kit. The serum CK-MB activity was determined with an immuno-inhibition assay kit. The overall sensitivity of H-FABP, within 12 hours after the appearance of symptoms, was 92.9%, while it was 88.6% with myoglobin and 18.6% with CK-MB. The overall specificity of H-FABP was 67.3%, while it was 57.1% with myoglobin and 98.0% with CK-MB. The diagnostic efficacy rates with these markers were 86.2% (H-FABP), 80.4% (myoglobin) and 39.2% (CK-MB), respectively. The diagnostic validity of H-FABP was further assessed by receiver operating characteristic (ROC) curve analysis. The area under the curve (AUC) of H-FABP was 0.921, which was significantly greater than with myoglobin (AUC: 0.843) and CK-MB (AUC: 0.654). These parameters, such as sensitivity, specificity, diagnostic efficacy and diagnostic accuracy, obtained for patients with chest pain within 3 hours and/or 6 hours after the onset of symptoms were almost the same as those for patients within 12 hours after symptoms. H-FABP is more sensitive than both myoglobin and CK-MB, more specific than myoglobin for detecting AMI within 12 hours after the onset of symptoms, and shows the highest values for both diagnostic efficacy and ROC curve analysis. Thus, H-FABP has great potential as an excellent biochemical cardiac marker for the diagnosis of AMI in the early phase.

The effect of modified ultrafiltration in pediatric open heart surgery

Since 1997 we have performed modified ultrafiltration (MUF) in pediatric open heart operations. To elucidate the clinical effects of MUF, patients under 20 kg in weight who underwent corrective open heart operation since 1997 are divided into 2 cohorts according to the enforcement of MUF (control group versus MUF group) retrospectively. Procedures, age, bodyweight, cardiopulmonary bypass (CPB) time, operation time, amount of donor blood use, postoperative inotrope dose, postoperative intubation time, and postoperative gas exchange capacity of lung expressed with respiratory index (RI) were compared between groups. Furthermore, a multiple linear regression analysis was performed to find independent correlates with postoperative RI. Finally scattergrams of intubation time and RI were drawn against several factors. In univariate analyses, the MUF group had significantly shorter intubation time and better RI. Multivariate analysis revealed that the enforcement of MUF was an independent correlate of postoperative RI. Analyses on the scattergrams revealed that the above mentioned favorable effects of MUF were prominent in the patients younger than 3 years or weighing less than 10 kg. We concluded that MUF had significant effects on pulmonary function preservation in pediatric open heart operations, especially for smaller children.

Physiological significance of hyperpolarization-activated inward currents (Ih) in smooth muscle cells from the circular layers of pregnant rat myometrium

The properties of hyperpolarization-activated current in pregnant rat uterus (17-19 days gestation) were investigated using microelectrode and patch-clamp techniques, and isometric tension recording. The resting membrane potentials were -58.4 mV and -48.5 mV in longitudinal and circular muscle cells, respectively. Application of hyperpolarizing current pulses produced a time-dependent anomalous inward rectification of membrane potential only in circular muscle cells. Under voltage-clamp conditions, inward currents (Ih) were activated by long hyperpolarizing pulses below -60 mV in circular but not in longitudinal muscle cells. Application of extracellular but not intracellular Cs+ reduced the amplitude of I(h) in a concentration-dependent manner (an IC50( of 0.15 mM). The reversal potential for Ih was -26.2 mV and the slope conductance was 5 nS/pF. Changes in [K+]o and [Na+]o shifted the reversal potential, and Ih amplitude increased with excess [K+]o and decreased with low [Na+]o. The steady-state activation of Ih was well fitted by a Boltzmann equation with a half-activation potential of -84.3 mV and a slope factor of 9.6 mV. Time courses of activation and deactivation of the current strongly depended on membrane potential, and were well fitted by a single exponential function. The activation time constant of Ih was dependent on temperature. In isometric tension recording, application of extracellular Cs+ to the circular muscles reduced the frequency, but not the amplitude, of spontaneous contractions in a concentration-dependent manner. It is concluded that in pregnant rat uterus Ih channels are predominantly distributed in smooth muscle cells from the circular layer. Since Ih is activated at the resting membrane potential, it is likely that this current contributes to the maintenance of resting membrane potential and spontaneous activity in circular smooth muscle cells of late pregnant rats.

Analysis of postoperative complications after esophagectomy for esophageal cancer in patients receiving neoadjuvant therapy

Postoperative complications were investigated in 72 patients who received neoadjuvant therapy with esophagectomy. Preoperative chemotherapy consisted of 5-fluorouracil (700 mg/m2/day, on days 1 to 5), cisplatinum (70 mg/m2/day, on day 1) and leucovorin (20 mg/m2/day, on days 1 to 5). Preoperative chemoradiotherapy consisted of cisplatinum combined chemotherapy and radiotherapy (total dosage of 30-70 Gy). The incidence of postoperative pneumonia (16%) and anastomotic leakage (24%) in the preoperative chemotherapy group was slightly higher than that in the control group (n = 506), and mortality (6.0%) after esophagectomy in the preoperative chemotherapy group was higher than that (2.4%) of the control group. Postoperative morbidity and mortality were observed more frequently in patients who received two cycles of the chemotherapy than those receiving only one cycle. Postoperative complications occurred more frequently in patients suffering high grade toxicities due to the preoperative chemotherapy. The highest preoperative serum creatinine value correlated to that of postoperative period (r = 0.6494). The use of the preoperative chemoradiotherapy with a total exposure dosage of 60 Gy or more significantly increased the postoperative pneumonia rate (67%; p < 0.05) compared to the group receiving 40 Gy or less. The mortality rate (33%) also increased. The second cycle of the preoperative chemotherapy should be cancelled if patients suffer high grade toxicities during or after the first cycle, and the total exposure dosage of the preoperative chemoradiotherapy should be limited to 40 Gy or less.

[Assessment of internal thoracic artery grafts using duplex scanning]

In an effort to develop a noninvasive method to evaluate flow characteristics of the internal thoracic artery grafts (ITAG) after coronary artery bypass grafting, we performed duplex scanning of ITAGs of 51 patients who underwent bypass grafting. The ITAG was visualized with a duplex scanner of 7.5 MHz through the first or second left intercostal space. The visualization of the ITAG was adequate to make reliable measurements in 47 patients (92.2%). The diameter of the vessel, systolic peak velocity, and diastolic peak velocity were recorded, and systolic flow volume, diastolic flow volume, velocity ratio, flow volume ratio, and diastolic flow volume fraction were calculated. The velocity ratio, flow volume ratio, and diastolic flow volume fraction were markedly higher in the unstenotic subjects than in the stenotic subjects. In the group in which severe LAD stenosis were recognized preoperatively, both systolic and diastolic flow volumes were increased compared with moderately stenotic group. No differences in flow characteristics could be demonstrated between the subjects with old anterior myocardial infarction and without it. In 10 patients in whom flow pattern was abnormal or not identified, angiography revealed graft stenosis or predominant native coronary arterial flow. Duplex scanning is thought to be a reliable, sensitive, and noninvasive technique for the assessment of the ITAG.

[Emergency coronary artery bypass grafting with integrated myocardial protection]

In the following retrospective study we reviewed the early postoperative results of emergency CABG; the myocardial management was achieved by utilization of integrated myocardial protection including warm cardioplegic induction, performed at our hospital. From April 1st 1994 to October 30th 1998; 63 patients underwent emergency CABG with integrated myocardial protection. All surgical procedures were performed within 6 hours from the onset of disease or admission transferred from another hospitals. Age ranged 48 to 86 years (mean 69.9 +/- 8.5; 41 male, 22 female). AMI was present in 52, UAP in 11. Preoperative PTCA was done in 20 and IABP was inserted in 53. Cardiogenic shock in 26, mechanical complications in 6, three vessel disease in 48 and LMT disease in 17 was present. Eight patients (12.7%) died in the early postoperative period. Among evaluated risk factors for early postoperative death; the occurrence of cardiogenic shock, mechanical complications of AMI, preoperatively done PTCA and prolonged CPB time were significantly increasing the mortality rate in early postoperative death.

[Prosthetic valve replacement in children]

Between 1975 and 1998, 27 patients aged 3 months to 14 years underwent replacement of the aortic, mitral, tricuspid, and pulmonary valves. Five different types of prosthetic valves were used; three were mechanical valves and two were bioprosthetic valves. There were 3 hospital deaths. Among the 24 survivors there were 4 late deaths. Arrhythmia requiring pacemaker implantation occurred in 2 cases after AVR and TVR. Thromboembolic events occurred in 3 patients, all with mechanical valves in pulmonary position. Infective endocarditis occurred in 1 patient after PVR with a mechanical valve. No bleeding complication occurred among the patients on a regimen of Coumadin and Dipyridamole. Two patients, both with Hancock bioprosthesis, required a second valve replacement on account of severely calcified changes. Mechanical valves in left side heart had a satisfactory long-term performance. One patient who had undergone MVR for congenital parachute mitral valve received reoperation for growth. A larger sized prosthetic valve should be used at the first replacement, and special procedures including supra-annular positioning or annular augmentation are recommended for MVR or AVR respectively.

Long term follow-up of atrioventricular valve function after repair of atrioventricular septal defect

To elucidate the factors which are associated with early and late operative results of atrioventricular septal defects, 102 consecutive patients who underwent reparative operation of atrioventricular septal defects (AVSD) in our institution since 1968 were studied. Our operative technique was basically the same through this period. That is the two patch method in its complete form (the so-called Shirotani's method) and preferential use of cleft closure supplemented with Kay-Reed-Wooler type annuloplasty. Early mortality (< 30 days) rate was 18.6%. More than 80% of the early deaths were not related to atrioventricular valve malfunction. Non-complete closure of the cleft, high preoperative pulmonary vascular resistance, deficient atrioventricular valve, and complete form showed independent correlations with early mortality in multiple logistic regression analysis. For operative survivors, event-free survival curves, for atrioventricular valve related reoperations were drawn for various factors. Two late deaths and 3 late atrioventricular-valve-related reoperations occurred. The event-free actuarial survival for operative survivors at 5, 10, and 20 years were 97.0%, 89.4%, and 89.4%, respectively. The survival analysis revealed that preoperative high pulmonary vascular resistance, preoperative severe atrioventricular regurgitation, and preoperative large cardiothoracic ratio in chest radiogram were related with late event occurrence. Higher early mortality in our series may be attributable to relatively advanced pulmonary vascular occlusive disease rather than post repair atrioventricular valve malfunction. On the other hand, our late results were rather good. We concluded that the Shirotani's method and preferential use of cleft closure supplemented with Kay-Reed-Wooler type annuloplasty was effective for most of atrioventricular valves in atrioventricular septal defects. Early surgical intervention before pulmonary vascular disease progression or atrioventricular valve regurgitation development is also important.

Scintigraphic evidence for a specific long-chain fatty acid transporting system deficit and the genetic background in a patient with hypertrophic cardiomyopathy

The mechanism of cardiac uptake of long-chain free fatty acids has not been fully determined. We encountered a hypertrophic cardiomyopathy patient who showed a lack of cardiac uptake of 2 different types of long-chain fatty acid analogues on the scintigraphic images. Flow cytometric analysis revealed no platelet or monocyte CD36 molecule expression (type I CD36 deficiency) and his CD36 gene showed homozygous mutation for 478C to T substitution, leading to an abnormal CD36 amino acid sequence. These findings strongly suggest that a specific transporting system rather than a simple diffusion is commonly involved in the cardiac uptake of long-chain free fatty acids in humans, and that the CD36 protein is the most likely candidate for the specific transporter and to explain scintigraphic defects on fatty acid imaging.

CD36 mediates long-chain fatty acid transport in human myocardium: complete myocardial accumulation defect of radiolabeled long-chain fatty acid analog in subjects with CD36 deficiency

Long-chain fatty acids (LCFA) are the major energy substrate for heart and their oxidation is important for achieving maximal cardiac work. However, the mechanism of uptake of LCFA by myocardium has not been clarified. We previously reported that bovine myocardial LCFA transporter has a sequence homology to human CD36. Clinically, total defect of myocardial uptake of radiolabeled long-chain fatty acid analog [123I-BMIPP: Iodine-123 15-(p-iodophenyl)-(R,S)-methylpentadecanoic acid] has been reported in some restricted cases, but the etiology has not been clarified. In the present study, we analyzed CD36 expression and CD36 gene in subjects who showed total lack of myocardial 123I-BMIPP accumulation, and, vice versa, evaluated myocardial 123I-BMIPP uptake in subjects with CD36 deficiency. Four unrelated subjects were evaluated, Two were found to have negative myocardial LCFA accumulation by 123I-BMIPP scintigraphy, after which the expression of CD36 on their platelets and monocytes was analyzed. Remaining two subjects were identified as CD36 deficiency by screening, then 123I-BMIPP scintigraphy was performed. Expression of CD36 on platelets and monocytes was measured by flow cytometric analysis. The molecular defects responsible for CD36 deficiency was detected by allele-specific restriction enzyme analysis. CD36 expression was totally deficient in all 4 subjects on both platelets and monocytes. Two subjects were homozygous for a 478C-->T mutation. One was heterozygous for the dinucleotide deletion of exon V and single nucleotide insertion of exon X, and remaining one was considered to be heterozygous for the dinucleotide deletion of exon V and an unknown gene abnormality. All cases demonstrated a completely negative accumulation of myocardial LCFA despite of normal myocardial perfusion, which was evaluated by thallium scintigraphy. In addition, all cases demonstrated apparently normal hepatic LCFA accumulation Thus, these findings suggested that CD36 acts as a major myocardial specific LCFA transporter in humans.

Double cardiac rupture after direct infarct coronary angioplasty: report of a case

The occurrence of double cardiac rupture (DCR) after a successful direct infarct coronary angioplasty (DICA) is extremely uncommon. We describe herein the case of a patient who underwent delayed DICA and despite successful recanalization, subsequently suffered DCR, as a postinfarction ventricular septal defect (PIVSD) with left ventricular free wall rupture (LVFWR). Emergency surgery was performed, and the patient is now doing well more than 2 years after his operation. The possible mechanisms of DCR after delayed DICA are discussed following the presentation of this unusual case.

A brimmed valved conduit in repair of fibrous skeleton abscess

Aortomitral common annular involvement, which is not uncommon in infective endocarditis, necessitates deliberate surgical procedures. To repair fibrous skeleton abscess accompanied with annuloaortic ectasia, we used a brimmed valved conduit. Tension-free reconstruction of the aortic root and aortomitral common annulus was easily performed with this method.

[Training of personnel for work in home medical care and social welfare]

Our foundation initiated another home nursing station last year, bringing to 7 the number of social welfare institutions we are running (hospital, elderly, special elderly, day service, home support center, nursing station). We are trying to maintain close communication between the institutions and local community, but service in keeping with the demand is more necessary than ever. Moreover, in supplying medical care and welfare services, we are working harder for very close communication with those on the spot. Among employees the call is also for faster, more sure communication for dealing with matters on a "quality work" basis. From the earlier attitude of local medical and welfare institutions of "Bring them here to our hospital or facility," to "We'll come there," a definite change in thinking has begun to take over now. In the home care and Welfare office end of things, while "business ability and skill" are important as ever, "attitude" has become a large factor in doing the job among employees. The report gives actual examples of training of personnel to handle these various tasks with greater ability.

CD36 abnormality and impaired myocardial long-chain fatty acid uptake in patients with hypertrophic cardiomyopathy

Some patients with hypertrophic cardiomyopathy (HCM) demonstrate abnormal myocardial long-chain fatty acid (LCFA) metabolism. However, the exact mechanism involved is unknown. Recently, it was proposed that myocardial cells take up LCFAs via a specific mechanism, in which the CD36 molecule has been implicated as a possible candidate molecule. In addition, a high prevalence of CD36 deficiency was also found in a small number of HCM patients. Accordingly, the investigation of abnormality of the CD36 molecule in a large number of HCM patients may be useful in finding the possible cause of HCM. Moreover, the analysis of myocardial LCFA uptake in patients with molecular abnormalities may be helpful in understanding the possible function of this molecule. In this study, in order to discover the relationship between HCM and the CD36 molecular abnormality, the expression level of platelet CD36 and CD36 cDNA in 55 HCM patients was analyzed. Twelve patients showed negligible (<5%) CD36 expression on their platelets. Among them, one was found to be homozygous for the C-478-->T substitution and 6 were heterozygous for the C-478-->T substitution. In 9 patients, CD36 was expressed by less than 50% of the platelets. One of them was found to be heterozygous for the C-478-->T substitution. Two other patients were also found to be heterozygous for this point mutation, although their platelets expressed CD36. Thus, 23 out of 55 (41.8%) HCM patients had negligible (<5%) or reduced (<50%) levels of CD36 expression on platelets, or had a point mutation of CD36 cDNA. These 55 HCM patients were also evaluated with myocardial scintigraphy both for LCFA uptake and perfusion, which showed a moderate to severe discrepancy between myocardial LCFA accumulation and myocardial perfusion in 95.5% of the patients (21/23). On the other hand, 70% of the patients with normal (>90%) CD36 expression (14/20) did not show any severe discrepancies between myocardial LCFA accumulation and myocardial perfusion. These data could suggest that abnormal myocardial LCFA metabolism seen in HCM patients may be related to abnormality of the CD36 molecule, and that abnormalities of this molecule may be linked to the cause of some types of HCM.

[A case of quadricuspid aortic valve associated with aortic steno-insufficiency]

A case of quadricuspid aortic valve associated with aortic steno-insufficiency was described. A 60-year-old man who had been shown to be suffering from heart murmur was admitted to our hospital. Both aortogram and echocardiogram showed a significant aortic insufficiency with mild stenosis. The aortic valve revealed 4 cusps consisting of 3 equal cusps and a smaller cusp and it had a poor coaptation and mild calcification at each commissure. The coronary orifices were normally located. Aortic valve replacement was carried out with a 25 mm St. Jude Medical valve. Histological findings showed edematous and fibrous changes. His postoperative clinical course was uneventful. Quadricuspid aortic valve is rare and the literatures were reviewed with 33 reported cases in Japan.

[A case report of coronary artery bypass grafting (CABG) and graft replacement of the ascending aorta for coronary artery disease associated with dissection of the ascending aorta]

A 64-year-old woman waiting for CABG for triple coronary artery disease admitted to our hospital due to chest oppression. One week after the admission, pericardiotomy was performed and blood in the pericardial effusion was found. Emergent chest CT scan revealed dissection of the ascending aorta (DeBakey II) with occluded false lumen. Because her condition was stable, concomitant operation of graft replacement of the ascending aorta and triple coronary artery bypass grafting were performed 3 months after the medical therapy. Her postoperative course was uneventful and the patient remains asymptomatic.