[The assessment of blue mechanism by measuring the threshold versus intensity curve under flashed background]

The threshold versus intensity curve with brief blue stimuli with a flashing background of the same wavelength was measured in normal subjects and subjects with several kinds of optic nerve and retinal diseases. In young normal subjects the threshold curve rose sharply away from the line measured under the same conditions but without flashing blue background, as has been reported in measurements with light of long wavelengths. In the convalescent stage of optic neuritis, diabetic retinopathy, and central serous chorioretinopathy, the threshold curves presented two patterns; one pattern was shifted upward and the other shifted upward and to the right. We suggest that this method with short wavelength light is useful in differentiating retinal diseases from the change of optic media, and for layer-by-layer diagnosis of retinal diseases.

[Assessment of left ventricular contraction with LV Emax during cardiopulmonary bypass in patients with open heart surgery]

There are few reports on the assessment of left ventricular contraction during cardiopulmonary bypass (CPB) in open heart surgery. LV Emax is thought to be a load-independent index of left ventricular function. We used a left ventricular conductance catheter to measure LV Emax from "non-working beating heart" during CPB in 16 patients who underwent open heart surgery. During CPB, at 45 minutes after aortic declamping, changes of heart rate with atrial pacing (120/min) did not change LV Emax, but after intravenous dobutamine administration (DOB, 10 micrograms/kg/min) LV Emax increased by 26% (p < 0.01). DOB increased LV Emax in 14 of 16 patients during CPB. These 14 patients were weaned from CPB without difficulty. But in 2 other patients DOB didn't increase LV Emax during CPB. In order to be weaned from CPB, the two patients needed epinephrine and intraaortic balloon pumping. We concluded that change of LV Emax made by intravenous administration of dobutamine is one of useful indexes to assess left ventricular contractility during cardiopulmonary bypass.

Neurite promoting activity of collagens on embryonic neurons: decreased effect at the postnatal stage

We studied the in vitro neurite outgrowth activity of fibronectin, laminin, heparan sulfate proteoglycan, type I collagen, type IV collagen, and type VIII collagen in cholinergic neuronal cell lines and primary cultured neurons. All these substances had high neurite promoting activity on primary cultured neurons from embryonic mouse brain. However, collagens had no such an effect on primary cultured neurons from postnatal brain. When neuronal cell lines were used, collagens and other extracellular matrix substances were equally and highly effective on cells originated from embryonic brain, but collagens were less effective on cells from postnatal brain. These findings suggest that postnatal neurons lose the neuritic responsiveness to collagens earlier than that of other ECM.

Suppression of allograft responses by combining donor alloantigen-specific intravenous presensitization with suboptimal doses of FK506

C57BL/6 (B6) mice were injected i.v. with class I H-2-disparate B10.QBR spleen cells (10(7)/mouse). This regimen, termed "donor alloantigen-specific i.v. presensitization" (DSP), induced almost complete elimination of anti-B10.QBR mixed lymphocyte reaction/IL-2 production but did not affect the generation of CTL responses. Repeated (5 or 11 times) administration in vivo (over 7 or 18 days) of FK506 at suboptimal doses (0.75-1.0 mg/kg/day) failed to eliminate the capacities to exhibit MLR/IL-2 production and to generate CTL responses. Prolongation of skin graft survival was not induced by either of a single DSP or FK treatment (0.75-1.0 mg/kg/day, 11 times during 18 days) alone, but by the combination of these. Such combined treatment also resulted in almost complete reduction of CTL responses before (5 rounds of FK injection) or after (11 rounds of FK injection) recipients were engrafted with B10.QBR skin grafts. Under conditions in which lymphoid cells from mice receiving both treatments failed to generate CTL responses, the addition of recombinant IL-2 to cultures restored the CTL generation, suggesting that CTL precursors themselves are not attenuated by the combined treatment. Both prolongation of graft survival and suppression of CTL responses were obtained when the administration of FK506 was started before but not after DSP. Prolongation of graft survival could also be obtained in class I and II MHC-disparate combinations when the combined treatment was performed in a particular protocol. These results indicate that (1) DSP alone fails to prolong graft survival in class I and class I and II MHC-disparate combinations; (2) such failure is ascribed to the induction of CTL responses by CTL precursors and CTL helpers, both of which are DSP-resistant; (3) the administration of suboptimal doses of FK506 is not sufficient for the suppression of CTL responses, but is effective selectively for suppressing DSP-resistant CTL helpers; and (4) the combination of DSP with FK506 treatment in an appropriate protocol can thus prolong graft survival through the suppression of CTL-involved as well as CTL-independent graft rejection pathways.

[Intraoperative assessment of left ventricular function with left ventricular pressure-volume relationships in patients with open heart surgery]

There are few reports on the assessment of the left ventricular function from left pressure-volume relationships intraoperatively in open heart surgery. LV Emax, Ea/Ees and EW/PVA efficiency were assessed intraoperatively by using a left ventricular conductance catheter in patients with aortocoronary bypass. After dobutamine administration (DOB, 10 micrograms/kg/min), LV Emax was increased by 33 +/- 23% during cardiopulmonary bypass (CPB) and 60 +/- 38% after weaning from CPB. Ea/Ees changed from 2.14 +/- 1.36 to 1.08 +/- 0.47 after weaning from CPB with dobutamine administration. EW/PVA efficiency changed from 52 +/- 12% to 66 +/- 10%. The change of LV Emax after dobutamine administration was correlated with the change of LV Emax after weaning from CPB and was correlated with Ea/Ees and EW/PVA efficiency after weaning from CPB. We concluded that measuring LV Emax before and after dobutamine administration during CPB is useful to assess left ventricular contraction clinically.

[Right ventricular myxoma--case report and review of the literature]

Primary tumors of the heart are rare, with the most common being myxoma, although myxoma of ventricular origin are uncommon. A careful review of the literature showed that 72 patients worldwide had cardiac myxomas located in the right ventricle. A 13-year-old asymptomatic girl with no previous history of cardiac disease was referred to a local hospital for evaluation of a heart murmur detected during a routine medical examination. Right ventricular myxoma was diagnosed and confirmed by echocardiogram, angiocardiography, CT, and MRI, MRI was firstly performed of right ventricular myxoma, and that showed right ventricular myxoma and the myocardium at the same intensity. Surgery was performed by first opening the right atrium. A lobulated mass was visualized through the tricuspid valve. Using a long needle, we confirmed that the wall was attached to the pedicle of the myxoma. Right ventriculotomy was subsequently performed in this region. The mass was passed through the tricuspid valve, and was reseated along with surrounding myocardium but with minimal excision of the right ventricular wall. The excised myxoma weighed 11 g, and had developed a short and small pedicle (5 mm x 5 mm) on the free wall and septum of the right ventricle. The patient recovered uneventfully and was discharged two weeks after the operation.

Lung perfusion SPECT in predicting postoperative pulmonary function in lung cancer

The aim of this prospective study is to evaluate the availability of preoperative perfusion SPECT in predicting postoperative pulmonary function following resection. Twenty-three patients with lung cancer who were candidates for lobectomy were investigated preoperatively with spirometry, x-ray computed tomography and 99mTc macroaggregated albumin SPECT. Their postoperative pulmonary functions were predicted with these examinations. The forced vital capacity and the forced expiratory volume in one second were selected as parameters for overall pulmonary function. The postoperative pulmonary function was predicted by the following formula: Predicted postoperative value = observed preoperative value x percent perfusion of the lung not to be resected. The patients were reinvestigated with spirometry at 3 months and 6 months after lobectomy, and the values obtained were statistically compared with the predicted values. Close relationships were found between predicted and observed forced vital capacity (r = 0.87, p < 0.001), and predicted and observed forced expiratory volume in one second (r = 0.90, p < 0.001). The accurate prediction pulmonary function after lobectomy could be achieved by means of lung perfusion SPECT.

Sudden death of calves by experimental infection with Strongyloides papillosus. IV. Electrocardiographic and pneumographic observations at critical moments of the disease

Electrocardiographic and pneumographic observations at critical moments were carried out on five calves that died suddenly following experimental infections with Strongyloides papillosus. Time which elapsed during these critical moments was calculated from the time of observation of ventricular flutter (VF) to the appearance of accelerated respiration and cessation of respiration. The beginning of accelerated respiration ranged from -19 to 41 s after VF. Time (minutes:seconds) of cessation of respiration ranged from 2:10 to 3:50 after VF. The results of the experiment suggested sudden cardiac death as the cause of death in calves following infection with Strongyloides papillosus.

Trophic effect of erythropoietin and other hematopoietic factors on central cholinergic neurons in vitro and in vivo

In vitro granulocyte colony-stimulating factor (G-CSF), macrophage colony-stimulating factor (M-CSF), erythropoietin (EPO), and erythroid differentiation factor (EDF) augmented choline acetyltransferase (ChAT) activity in mouse embryonic primary septal neurons and in cholinergic hybridoma cell line, SN6.10.2.2. This is similar to the effects seen with interleukin-3 (IL-3) or granulocyte-macrophage colony-stimulating factor (GM-CSF). Moreover, in vivo GM-CSF and EPO promoted survival of septal cholinergic neurons in adult rats which had undergone fimbria-fornix transections. These results suggest that some of the hematopoietic factors act on cholinergic neurons as 'neurotrophic factors' to influence the differentiation, maintenance and regeneration of these neurons.

A new method using computed tomographic scan to measure the rectus femoris-patellar tendon Q-angle comparison with conventional method

The Q-angle should be the angle generated by a line connecting the anteroinferior iliac spine (AIIS), the bottom of the groove of the femoral condyle, and the tibial tubercle. The Q-angle was measured by computed tomography (CT) in 43 lower limbs with recurrent patellar dislocation and 26 normal controls. The mean Q-angle was 20 degrees in the dislocated group and 13 degrees in controls, a significant difference. No significant difference was found in the Q-angle between the dislocated and control groups using the conventional method. Lower limb rotation had little effect on accuracy of the method.

Role of endothelin ETB receptors in bronchoconstrictor and vasoconstrictor responses in guinea-pigs

In anesthetized and ventilated guinea-pigs, intravenous injections of endothelin (ET)-1 (0.5 nmol/kg), ET-3 (0.5 nmol/kg), and [Ala1,3,11,15]ET-1 (20 nmol/kg), an ETB-selective receptor agonist, induced bronchoconstrictor and transient vasoconstrictor responses. Only the ET-1-induced transient vasoconstriction was followed by a secondary sustained pressor response. The ETA-selective receptor antagonist, BQ-123 (1 mg/kg i.v.), attenuated only the sustained pressor response. These results indicate that the bronchoconstrictor and transient vasoconstrictor responses to endothelins in guinea-pigs are mediated by ETB receptors, whilst the sustained pressor response is mediated by ETA receptors. The thromboxane A2 receptor antagonist, L-670,596 (0.5 mg/kg, i.v.) and a high dose of BQ-123 (30 mg/kg i.v.) abolished the bronchoconstriction only without affecting the transient pressor response to endothelin isopeptides. These results suggest that the ETB-mediated bronchoconstriction depends on thromboxane A2 formation. The different sensitivity of these ETB-mediated transient responses to BQ-123 suggests the possible existence of distinct ETB receptor subtypes.

Turbidimetric-kinetic assay of endotoxin in rumen fluid or serum of cattle fed rations containing various levels of rolled barley

A new, automated turbidimetric-kinetic (ATK) assay was used to quantitate bacterial endotoxin in rumen fluid or in serum of Holstein steers. The ATK method used Limulus amebocyte lysate (LAL) reagent with added beta-glucan (LAL-ES) which improved specific sensitivity to endotoxin. Design of the feeding trial permitted comparison of endotoxin levels found during consumption of a basal ration with those higher levels detected at various times following the introduction of increasing percentages of rolled barley to that basal ration. Both serum and ruminal endotoxin levels were significantly higher in steers on the higher concentrate rations. Peak endotoxin levels were detected 20 days following the change to the highest concentrate ration which contained 60% barley. Endotoxin levels from both sources subsequently decreased. Ruminal endotoxin stabilized at about 10 times the level, and serum endotoxin stabilized at 2 to 4 times the level, of that previously found during feeding of the basal ration. Test protocol included sample dilution and heating in order to avoid the effects of endotoxin inhibitors. Recovery rates for added endotoxin to either serum or rumen fluid supernates ranged from 120 to 136%. Coefficient of variation for endotoxin concentration in serum was lower than 10%, and in rumen fluid only slightly higher. There was significant correlation between ruminal concentration as measured by the ATK method and an alternative chromogenic substrate assay procedure. Changes in endotoxin level in experimental steers were those predictable from experience with naturally occurring incidents of grain engorgement. The ATK assay appears to be an accurate and rather simple technique which will prove useful for experimental and clinical studies in the future.

Glucose-induced insulin secretion and alpha 2-adrenergic receptor subtypes

alpha 2-Adrenoceptor antagonists have been investigated in human in vivo studies as new oral antihyperglycemic agents. alpha 2-Adrenoceptors are subdivided into alpha 2A and alpha 2B subtypes by using receptor-binding methods or cloning methods. This study was designed to determine the alpha 2-adrenergic receptor subtype(s) involved in glucose-induced insulin and glucagon secretion from the isolated perfused rat pancreas at a glucose concentration of 16.7 mmol/L. Both the alpha 2A-preferential agonist oxymetazoline and the non-subtype-selective alpha 2-agonist p-aminoclonidine, at concentrations above 10(-9) mol/L, significantly inhibited glucose-induced insulin secretion (p < 0.05 and p < 0.01, respectively) and stimulated glucagon secretion from 10(-7) mol/L, as compared with basal levels (p < 0.01, respectively). In contrast, the alpha 1-selective agonist phenylephrine, at concentrations up to 10(-6) mol/L, affected neither insulin nor glucagon secretion as compared with basal levels. Furthermore, the non-subtype-selective alpha 2-antagonist rauwolscine, at concentrations above 10(-6) mol/L, and the alpha 2A-preferential antagonist WB-4101, at 10(-5) mol/L, significantly antagonized the effects of 10(-7) mol/L p-aminoclonidine on both insulin and glucagon secretion (p < 0.01 and p < 0.05, respectively). In contrast, neither the alpha 1- and alpha 2B-selective antagonist prazosin nor the alpha 2B-preferential antagonist chlorpromazine, at concentrations up to 10(-5) mol/L, antagonized the effects of p-aminoclonidine. These results suggest that alpha 2A rather than alpha 2B-adrenergic agonism inhibits glucose-induced insulin secretion and stimulates glucagon secretion in the isolated perfused rat pancreas.

Close association between Streptococcus sobrinus in the saliva of young children and smooth-surface caries increment

Three hundred and thirty-eight children (age range 3-5 years) were examined for the presence of mutans streptococci in their saliva. They were divided into four groups according to the prevalent species that were isolated: (1) Streptococcus mutans and Streptococcus sobrinus group (S. mutans > or = 10(3) CFU/ml and S. sobrinus > or = 10(3) CFU/ml); (2) S. mutans group (S. mutans > or = 10(3) CFU/ml but S. sobrinus < 10(3) CFU/ml); (3) S. sobrinus group (S. sobrinus > or = 10(3) CFU/ml but S. mutans < 10(3) CFU/ml), and (4) children with mutants streptococci absent or barely detectable (mutants streptococci < 10(3) CFU/ml). The previous caries experience was compared among the groups, as was the caries increment during a 6-month period after the bacterial examination. The subjects in the S. sobrinus group had both higher caries and higher decayed teeth and surface increments than the S. mutans group. The mean decayed smooth-surface increment (delta d-surface) for the S. sobrinus group was 2.6 and was significantly higher than 0.8 for the S. mutans group. For the subjects with delta d-surface > or = 4, the mean number of S. sobrinus in the saliva was 4.29 x 10(5) CFU/ml and was significantly higher than 0.32 x 10(5) CFU/ml for the subjects without delta d-surface. There was no significant difference in the mean number of S. mutants in saliva between the subjects with and without delta d-surface. The prevalence of S. sobrinus in saliva was more closely associated with future caries activity, especially with smooth-surface caries increment, than the prevalence of S. mutants.

Botulinum toxin treatment for spasmodic dysphonia

Effective treatment of adductor type spasmodic dysphonia with botulinum toxin injection is presented. Patients showed objective and/or subjective improvement in phonation. The beneficial effect lasted for approximately 3 months. An immediate complication is temporary hoarseness or aphonia, mainly due to diffusion of BT into the adjacent muscles. This is avoided by limiting the injection to one vocal fold only and by keeping the dose at less than 5 units. Insertion technique of the needles, such as percutaneous and laryngoscopically controlled techniques, are discussed.

[An investigation of the recognition process for jukugo by use of priming paradigms]

Three experiments were conducted to examine the recognition process of the jukugo (two-kanji-compound word) from the following three points of view: (1) how jukugos are retrieved from memory (Exp. 1), (2) how jukugos are activated in the retrieval process (Exp. 2), and (3) how the representation of jukugos is structured in memory (Exp. 3). The experiments were carried out using priming paradigms in which subjects performed a lexical decision task. The results of Exp. 1 and Exp. 2 showed that the first kanji was used as retrieval cue for each jukugo and the activation of the first kanji facilitated the identification of jukugo in terms of meaning. In Exp. 3, it was suggested that the lexicon of jukugo was formed in such a structure that several jukugos containing in common the same first kanji are tied together, centering on the first kanji.

Evaluation of right ventricular function by regional wall motion analysis in patients after correction of tetralogy of Fallot. Comparison of transventricular and nontransventricular repairs

Right ventricular function was assessed by regional wall motion analysis and by global function in 62 patients after repair for tetralogy of Fallot. Its relation to surgical procedures, with special attention to right ventriculotomy, was investigated. Patients were classified as follows: group Ia (n = 17), transpulmonary-transatrial repair without right ventriculotomy; group Ib (n = 22), transpulmonary-transatrial repair with minimal right ventriculotomy and small transannular patch; and group II (n = 23), transventricular repair with or without transannular patch. For regional wall motion analysis, fractional area change was used for three anterior parts obtained from hemiaxis area analysis of the lateral right ventriculogram. Ejection fractions were used for global right ventricular function. Functional assessment was done both at rest and during isoproterenol infusion, which is a stress test to evaluate cardiac functional reserve. At rest, group Ia showed better right ventricular anterior wall motion as well as global ejection fraction than did group II. Group Ib showed a global ejection fraction comparable to group Ia, with better regional wall motion in the middle anterior part of the right ventricle despite the depressed upper and lower anterior parts of the right ventricle. Group II showed depressed wall motion of the middle anterior part and the resultant impaired global ejection fraction. During isoproterenol infusion, group Ia showed significant increase in fractional area change of all anterior parts and in global ejection fraction. Group Ib showed significant increases in fractional area change at the middle and lower parts and in global ejection fraction comparable with group Ia. Otherwise, group II showed no significant change in fractional area change, or in global ejection fraction, at the upper and middle parts. These results indicated that transpulmonary-transatrial repair for tetralogy of Fallot provided better postoperative global right ventricular function and its reserve, with less impaired regional wall motion, than did the transventricular repair.

[A case of thymoma with thymic cyst]

A 43-year-old man was pointed out an abnormal shadow on chest X-ray film. Chest CT showed a solid mass and a cyst at anterior superior mediastinum. Operation revealed a capsulated thymoma and a multilocular thymic cyst. PTH and CA19-9 level in the cystic fluid was elevated. Histological examination demonstrated the clear separation of the mixed type thymoma and the thymic cyst. There were few reports for cases of thymoma with a thymic cyst.

Alpha-2 adrenergic agonism stimulates islet glucagon release from perfused rat pancreas: possible involvement of alpha-2A adrenergic receptor subtype

Although insulin release is known to be inhibited by alpha-2 adrenergic agonism, the effect of alpha adrenergic agonism on islet glucagon release remains controversial. Alpha-2 adrenoceptors are subdivided into alpha-2A and alpha-2B subtypes using receptor binding methods or cloning methodology. This study was designed to confirm the involvement of the alpha-2 adrenoceptor and its subtypes in glucagon release from the isolated, perfused rat pancreas. Both the alpha-2A preferential agonist oxymetazoline and the non-subtype-selective alpha-2 agonist clonidine induced concentration-dependent stimulation of glucagon release, starting at 10−8 and 10−7 mol/l, respectively (p<0.01). In contrast, neither of the two alpha-1 selective agonists, methoxamine and phenylephrine, at concentrations up to 10−6 mol/l affected glucagon release. Furthermore, the non-subtype-selective alpha-2 antagonist rauwolscine at concentrations of 10−6 and 10−5 mol/l and the alpha-1 and alpha-2A selective antagonist WB-4101 at 10−5 mol/l showed significant antagonism of 10−7 mol/l clonidine-induced glucagon release versus corresponding controls. Neither the alpha-1 and alpha-2B selective antagonist prazosin nor the alpha-2B preferential antagonist chlorpromazine, at concentrations up to 10−5 mol/l, antagonized the effects of clonidine. None of the eight drugs, at the concentrations tested, affected insulin release with 5.5 mmol/l glucose. These results suggest that in rats islet glucagon release induced by alpha adrenoceptor agonism is mediated through alpha-2 adrenoceptors, possibly the alpha-2A subtype.

Synthesis of radiopaque cyclophosphazene monomers, properties of bulk polymers and their application to composite resin

A series of studies was conducted on the synthesis of polyfunctional cyclophosphazene monomers having radiopacity and a polymerization group in the same molecule, and their properties and applicability to composite resin were examined. Using octachlorocyclotetraphosphazene, P4N4Cl8 (4PNC), monomers were synthesized by replacing the 1-4 of chlorine (Cl) with p-bromophenol (BrC6H4OH, BrPh), and replacing the residual number of Cl, 7-4, with 2-hydroxyethyl methacrylate [CH2:C(CH3)COOCH2CH2OH](HEMA), so as to obtain four kinds of transparent monomer having radiopacity and a polymerization group in the same molecule. We then analyzed these monomers and examined their physical properties after bulk-polymerization. Next, we prepared an organic composite filler using 4PN-(BrPh)3-(EMA)5 monomer, which showed comparatively good radiopacity, to produce a new experimental radiopaque composite resin. Although radiopacity improved in accordance with the increase in the number of BrPh molecules replaced, the mechanical properties of the polymer became poorer. Similarly it was proved that the radiopacity of composite resin made with 4PN-(BrPh)3-(EMA)5 monomer was equivalent or even superior, compared with the radiopacity of the front tooth. Consequently, it was shown that these synthesized monomers can be applied to visible light-cured radiopaque composite resin.

Effect of hyperlipidemia on cardiovascular responses to adrenergic stimulation in piglets

This study was designed to assess the effect of hyperlipidemia on cardiovascular responses to adrenergic stimulation in a porcine model. Four-week-old piglets (n = 10) were divided into two groups; one fed a control diet and the other was fed an atherogenic diet for 8 weeks. Cardiovascular responses were evaluated to both norepinephrine (NE; 0.5 and 2.5 micrograms/kg) and isoproterenol (ISO; 0.1 and 0.5 microgram/kg) from simultaneous recordings of femoral arterial pressure, heart rate, left intraventricular pressure and left intraventricular dP/dt. It was found that no significant difference in the baseline values of cardiovascular function was observed between the control and hyperlipidemic groups. However, in the hyperlipidemic group as compared with the control group: 1) arterial blood pressure responses to NE were significantly increased (P less than 0.05), 2) cardiac contractile responses to NE and ISO were significantly potentiated (P less than 0.05), and 3) reflex bradycardia in response to increasing arterial blood pressure did not occur. These findings indicate that hyperlipidemia can potentiate the cardiovascular responses to adrenergic stimulation, whereas reflex cardiovascular regulation is somewhat altered by hyperlipidemia. Conceivably, these observations may have relevance to the possible role of the mechanism of the interaction of hyperlipidemia and hypertension in atherogenesis.