Does nitric oxide mediate plasma extravasation induced by electrical stimulation of the superior salivatory nucleus in cat nasal mucosa?

The effects of electrical stimulation, applied to the superior salivatory nucleus (SSN) or the cervical sympathetic nerve, on vascular permeability in nasal mucosa were studied in 16 cats. Plasma extravasation was quantified by using Evans blue. Vascular permeability in the cat nasal mucosa was increased by the electrical stimulation of SSN. Plasma extravasation induced by SSN stimulation was reduced by administration of nitric oxide synthase (NOS) antagonist, N(omega)-nitro-L-arginine methyl ester (L-NAME). Administration of atropine did not affect increased vascular permeability by SSN stimulation. We conclude that neurogenic plasma extravasation in cat nasal mucosa evoked by the parasympathetic nerve is not mediated by cholinergic fibers but rather by nitric oxide.

Decreased expression of biliary glycoprotein in hepatocellular carcinomas

Biliary glycoprotein (BGP) is an adhesion and anti-cell-growth molecule of the carcinoembryonic antigen family. We have earlier demonstrated that BGP mRNA is expressed in hepatocellular carcinomas (HCCs) and the adjacent non-cancerous regions, neither of which express CEA and NCA mRNA. To define an expression level and pattern of BGP at the protein level in HCCs, TS135, a monoclonal antibody (MAb) against BGP, was prepared. This MAb clearly reacted with BGP with a molecular weight of 110 kDa and 85 kDa (BGP-110/85). It cross-reacted weakly with NCA-90 from NCA transfectants, but not at all with CEA-200 from the serum of a colon-cancer patient. The BGP transfectants of cultured hepatocellular carcinoma cHc-4 cells showed Ca2+-dependent cell aggregation, which was partially inhibited by modulating BGP on the cell surface with MAb TS135. Immunostaining of non-cancerous liver tissues with MAb TS135 indicated that BGP could be expressed in the bile canalicular domain of hepatocytes. In HCCs, the expression of BGP was predominantly found in the well-differentiated type, where the bile canaliculi and the apical portion of pseudoglands were positively stained, although their staining intensity and stained area were lower and more limited, respectively, than those of non-cancerous regions. The percentage of faintly positive and negative cases (n = 22) from the total (n = 30) was 73%. This suggests that the expression level of BGP decreased in HCCs as compared with adjacent non-cancerous regions.

Predominant role of local immunosuppressive effect in enhanced efficacy of liposomal FK506 in organ transplantation

Liposomal FK506 is a new formulation of FK506 that increases FK506 levels in the liver and decreases them in the kidney in comparison to conventional IV formulation. In the present study, the efficacy of liposomal FK506 was evaluated in canine kidney and liver transplantation models. Liposomal FK506 increased the immunosuppressive efficacy of FK506 in the liver transplantation model, but decreased it in the kidney transplantation model. These results suggest that local immunosuppressive effects with increased intragraft FK506 level would play an important role in enhancing the immunosuppressive efficacy of liposomal FK506 in liver transplantation.

No. 302, a newly synthesized [pGlu4,Cyt6]AVP(4-9) analogue, prevents the disruption of avoidance behavior

We investigated the effects of [pGlu4,Cyt6]AVP(4-9) fragments and its analogues on cycloheximide (CHX)-induced learning impairment in rats using the step-through-type passive avoidance test in rats. CHX (2.8 mg/kg, s.c.) significantly shortened the step-through latency in the retention trial. pGlu-Asn-Cys(Cys)-Pro-Arg-Gly-NH2 ([pGlu4, Cyt6]AVP(4-9); 10 ng/kg, s.c.), a major metabolite of arginine vasopressin, improved the CHX-induced learning impairment. Asn-Cys-Pro-Arg-OH ([Cys6]AVP(5-8); 1 ng/kg) corrected avoidance learning in the CHX-treated group, whereas neither Cys(Cys)-Pro-Arg-OH nor pGlu-Asn-Cys(Cys)-Pro-OH had any effect (1, 10 and 100 ng/kg, s.c.). pGlu-Asn-Ser-Pro-Arg-Gly-NH2 (No. 302), a newly synthesized [pGlu4,Cyt6]AVP(4-9) analogue, significantly prolonged the latency shortened by CHX at doses of 0.1, 1 and 10 ng/kg (s.c.). Asn-Ser-Pro-Arg-OH also improved the learning disruption induced by CHX, although the effective dose was 100 times higher than that of No. 302. The half-life of No. 302 in rat blood was about 5.5, 22 and 25 times longer than that of [pGlu4,Cyt6]AVP(4-9), [Cys6]AVP(5-8) and Asn-Ser-Pro-Arg-OH, respectively. These results suggest that [Cys6]AVP(5-8) is the minimal effective amino acid sequence in [pGlu4,Cyt6]AVP(4-9), and show that No. 302 is a potent, pharmacologically active peptide with high stability in the blood.

Efficacy and safety of preoperative percutaneous transhepatic portal embolization with absolute ethanol: a clinical study

BACKGROUND

Preoperative portal embolization has been performed by using various thrombogenic substances to increase the safety and resectability of liver surgery. We evaluated the clinical safety and efficacy of using absolute ethanol in preoperative portal embolization.

METHODS

Our study included 19 patients who had undergone right hepatic lobectomy. According to our criteria for right lobectomy of the liver, seven patients were not appropriate for the operation because of a high risk in each of postoperative liver failure. Those patients received preoperative right portal embolization with 11 to 32 ml absolute ethanol. The remaining 12 patients satisfied our criteria and received no preoperative embolization.

RESULTS

Although alanine aminotransferase concentrations increased dramatically after the embolization, all serologic changes reverted within 3 weeks. The mean volume of the nonembolized lobe increased from 320 cm3 to 619 cm3 and 667 cm3 2 and 4 weeks, respectively, after embolization. The mean regeneration rate of this lobe was 21.3 cm3 per day for the first 2 weeks and 11.4 cm3 per day for the first 4 weeks after embolization. All patients underwent right lobectomy of the liver and survived; none of the patients had severe complications associated with embolization or surgery. The postoperative survival periods were not statistically significant between the patients with and without preoperative portal embolization.

CONCLUSIONS

According to our criteria for liver surgery, the seven patients should not have undergone major surgery, but each underwent right lobectomy of the liver and all survived, showing that portal embolization with absolute ethanol brings about compensatory hepatic hypertrophy for major surgery and that its extreme effect on liver regeneration could widen the range of patients appropriate for liver surgery.

Extracellular fibrillar structure of latent TGF beta binding protein-1: role in TGF beta-dependent endothelial-mesenchymal transformation during endocardial cushion tissue formation in mouse embryonic heart

Transforming growth factor-beta (TGF beta) is a dimeric peptide growth factor which regulates cellular differentiation and proliferation during development. Most cells secrete TGF beta as a large latent TGF beta complex containing mature TGF beta, latency associated peptide, and latent TGF beta-binding protein (LTBP)-1. The biological role of LTBP-1 in development remains unclear. Using a polyclonal antiserum specific for LTBP-1 (Ab39) and three-dimensional collagen gel culture assay of embryonic heart, we examined the tissue distribution of LTBP-1 and its functional role during the formation of endocardial cushion tissue in the mouse embryonic heart. Mature TGF beta protein was required at the onset of the endothelial-mesenchymal transformation to initiate endocardial cushion tissue formation. Double antibody staining showed that LTBP-1 colocalized with TGF beta 1 as an extracellular fibrillar structure surrounding the endocardial cushion mesenchymal cells. Immunogold electronmicroscopy showed that LTBP-1 localized to 40-100 nm extracellular fibrillar structure and 5-10-nm microfibrils. The anti-LTBP-1 antiserum (Ab39) inhibited the endothelial-mesenchymal transformation in atrio-ventricular endocardial cells cocultured with associated myocardium on a three-dimensional collagen gel lattice. This inhibitory effect was reversed by administration of mature TGF beta proteins in culture. These results suggest that LTBP-1 exists as an extracellular fibrillar structure and plays a role in the storage of TGF beta as a large latent TGF beta complex.

Experimental studies of methemoglobinemia due to percutaneous absorption of sodium nitrite

OBJECTIVE

Methemoglobin formation caused by a liniment solution containing sodium nitrite (30 g/L and 140 g/L) was studied in rats with normal or abraded skin, by measuring the methemoglobin concentration before and after application of liniment solutions with differing nitrite concentration.

METHODS

Each liniment solution (120 microL) was applied. Methemoglobin was measured for 180 minutes using a hemoximeter. Simultaneously, arterial blood pressure and cutaneous blood flow was measured by laser Doppler flowmetry and a pressure transducer.

RESULTS

After the application of each liniment solution to normal skin, the methemoglobin concentration was not significantly modified depending on the time after application. Application of liniment solution to abraded skin (140 g/L) resulted in a marked increase in methemoglobin concentration. A remarkable decrease in arterial blood pressure and subcutaneous blood flow were observed after application of liniment solution to abraded skin (140 g/L).

CONCLUSIONS

Each of these findings are characteristic of nitrite and they imply the percutaneous absorption of nitrite. Regardless of the nitrite concentration, the methemoglobin concentration was consistently higher in abraded skin than in normal skin.

Supravalvular stenotic mitral ring with ventricular septal defect

BACKGROUND

Supravalvular mitral ring is exceedingly uncommon.

METHODS

We report a 4-year-old girl with supravalvular stenotic mitral ring and ventricular septal defect (VSD). The VSD was closed by a Dacron patch and the supravalvular ring was excised. For treatment of supravalvular mitral ring with obstruction, surgical resection is commonly performed.

RESULTS

There are no reports of long-term follow-up after resecting the supravalvular mitral ring.

CONCLUSION

In our case, no mitral stenosis was evident on postoperative echocardiogram performed 3 years after surgery.

[Surgical treatment of multidrug resistant pulmonary tuberculosis cases]

We report on the results of surgical treatment of pulmonary tuberculosis cases intractable to ordinary therapy due to acquired drug-resistance against multiple anti-tuberculosis drugs (MDR-Tbc).

MATERIAL AND METHOD

From 1983 to 1994, 54 patients were administered surgical treatments (60 interventions in all) for pulmonary tuberculosis. Among them, 46 were MDR Tbc cases (52 interventions in all) and were enrolled for this study. The Japanese criteria for drug resistance were referred to, the threshold of resistance in each drug being as follows, INH 0.1, RFP 50, EB 2.5, SM 20, KM 100, TH 25, EVM 100, CPM 100, CS 40, PAS 1 microgram/ml. Bacteriological examinations of sputa were repeated in the postoperative period until upto several years, and the continued absence of Tbc. bacilli for more than 12 months was considered as cured.

RESULTS

(1) 37 patients underwent removal of lung mass including tuberculous foci mainly fibrous cavitary lesions (40 interventions in all). The procedures are as follows 22 upper lobectomies and/or partial resections of adjacent lobes. 1 middle lobectomy. A lower lobectomy, 14 pneumonectomies, 2 segmentectomies. In 3 cases, multiple operations were carried out on 2 occasions; 2 upper lobectomies followed by completion pneumonectomies. 1 right upper lobectomy followed by left S3 segmentectomy. Except 2 cases having died of pneumonia and suicide within 12 months after operation, we have 38 cases available for evaluation. Bacteriological relapses were confirmed in 7 among 38 cases postoperatively. 2 of these 7 relapsed cases underwent additional completion pneumonectomies and attained complete cure. Bacteriological relapse-rate was therefore 18.4% (7/38) and the ultimate cure rate of pulmonary MDR-Tbc was 88.6% (31/35). (2) 7 patients underwent thoracoplasties (not corrective, once for each patient). In 2 cases bacteriological relapse was confirmed. Other 5 cases remained bacteriologically silent over a long postoperative period. (3) 4 patients underwent cavernostomies, 3 of them got satisfactory result in reducing the bacterial presence in the sputum (preoperative abundant bacilli (Gaffky 7, 8) turned mean-negative within 2 months after cavernostomy).

CONCLUSION

With the above-mentioned results we conclude that surgical treatment is highly effective in intractable pulmonary MDR Tbc cases.

[Diagnostic imaging of renal pedicle injury]

We reviewed the radiological findings of 8 patients with renal pedicle injury admitted to our emergency center from January 1986 through September 1995 and compared them with the previously reported findings. The patients included 3 with renal artery occlusion and 5 with avulsion or disruption of renal pedicle vasculature. Extended retroperitoneal hematoma such as contralateral pararenal or central parahilar hematoma was visualized in all 5 cases with avulsion or disruption of renal pedicle vasculature. Although lack of contrast enhancement of injured renal parenchyma is a hall-mark of renal pedicle injury, three cases did not demonstrate this typical finding. In these three cases, one showed partial and the others showed total enhancement of the injured renal parenchyma on contrast enhanced CT. Partial enhancement in one case was found to represent total occlusion of the main renal artery and an intact accessory polar branch on angiography. The other two cases showed total enhancement of the renal parenchyma, with renal vein perforation done and complete disruption of the main renal artery and vein in the other. The latter findings were thought to be due to the maintenance of vascular flow surrounded by hematoma. In conclusion, when central parahilar hematoma is identified, the possibility of renal pedicle injury should be considered even if the renal parenchyma is well enhanced.

[A patient with mitral stenosis due to infective endocarditis]

A 51-year-old woman presented with mild stenosis of the mitral valve which had become thickened and rigid due to infective endocarditis, manifesting as persistent fever of up to 40 degrees C and general fatigue of a few days' duration. A harsh systolic murmur was heard. Multiple blood cultures revealed alpha-streptococcus. Echocardiography disclosed asymmetric septal hypertrophy (interventricular septal thickness/posterior wall thickness, 19/14 mm) and systolic anterior wall motion of the mitral valve. Continuous wave Doppler ultrasonography showed a peak left ventricular outflow tract pressure gradient of 170 mmHg. Transesophageal echocardiography revealed vegetations on the anterior mitral leaflet, aortic valve and interventricular septum along the left ventricular outflow tract. In particular, the anterior mitral leaflet was thickened and moved poorly. The calculated mitral valve areas was 1.5 cm2 and peak diastolic left atrium-left ventricle pressure gradient was 7 mmHg. A specimen of the mitral valve did not reveal commissural adhesion, but the anterior mitral leaflet showed marked fibrous thickening caused by scarred vegetation. Based on these findings, the diagnosis was hypertrophic obstructive cardiomyopathy complicated by infective endocarditis and "mitral stenosis". Valvular regurgitation is a common complication of active and healed infective endocarditis. In contrast, infective endocarditis rarely causes valvular stenosis except for stenosis caused by large fungus vegetation.

Transthoracic transdiaphragmatic approach for hepatectomy of Couinaud's segments VII and VIII

For hepatectomy of Couinaud's segment VII or VIII, severe compression and mobilization of the liver is required to establish the operative field via the usual transabdominal approach. Compression of the cirrhotic liver impairs hepatic and systemic blood circulation, which may cause liver dysfunction. We adopted a transthoracic transdiaphragmatic approach for hepatectomy of segment VII or VIII in cirrhotic patients to establish a good operative field without compressing the liver. The aim of this study was to evaluate the benefits of this approach. Forty-four patients with hepatocellular carcinoma (HCC) complicating liver cirrhosis who underwent limited hepatectomy of Couinaud's segment VII or VIII were studied. The patients were randomized to two groups preoperatively: group I (n = 22), transabdominal approach; group II (n = 22), transthoracic transdiaphragmatic approach. There were no differences in preoperative liver function tests, hepatic functional reserve, or extent of tumor between the two groups. The operative time in group II was significantly shorter than that in group I (243 +/- 50 versus 313 +/- 80 minutes;p < 0.01). Operative blood loss in group II was also significantly smaller than that in group I (1190 +/- 1098 versus 2679 +/- 2267 g;p < 0.01). Serum lactate dehydrogenase levels on postoperative day 1 in group II were significantly lower than those in group I (587 +/- 154 versus 791 +/- 383 IU/L;p < 0.05). Major postoperative complications were significantly fewer in group II. It was concluded that the transthoracic transdiaphragmatic approach is a useful method for hepatectomy of segments VII and VIII in cirrhotic patients.

Continuous brachial plexus infusion of butorphanol-mepivacaine mixtures for analgesia after upper extremity surgery

We have recently reported that continuous administration of butorphanol into the brachial plexus neurovascular sheath provided superior analgesia compared with that obtained with continuous i.v. administration. Furthermore, we found that analgesia was most pronounced when a mixture of mepivacaine and butorphanol was given and that butorphanol alone ranked next. In this study, we increased the dose of butorphanol, compared with that used in our previous reports, and an initial bolus dose of butorphanol was administered into the brachial plexus neurovascular sheath just after surgery had ended. Thereafter, postoperative pain relief was estimated. In patients undergoing upper extremity surgery with continuous axillary brachial plexus block, group A received a bolus of 1 ml of physiological saline with 1.5% mepivacaine, 10 ml into the brachial plexus sheath followed by a continuous brachial plexus infusion of 0.5% mepivacaine with butorphanol 6 mg at a rate of 144 ml/ 72 h. Group B was given a bolus of butorphanol 1 mg (1 ml) with 1.5% mepivacaine, 10 ml into the brachial plexus sheath and a continuous brachial plexus infusion of 0.5% mepivacaine with butorphanol 6 mg at a rate of 144 ml/72 h. After operation, VAS scores did not differ between the two groups. The time to first use of supplementary analgesia did not differ significantly between the two groups and there were no significant differences in the number of patients who required supplementary analgesia. These results indicate that continuous butorphanol 2 mg day-1 with 0.5% mepivacaine provided sufficient postoperative analgesia after upper limb surgery.

The possible role of remnant-like particles as a risk factor for sudden cardiac death

Postmortem plasma lipid and lipoprotein levels were analyzed in two groups of Japanese subjects who died suddenly and unexpectedly due to cardiac (n = 93) or non-cardiac (n = 26) causes. No individuals in either group had a significant medical or cardiac history. In this study, we measured plasma total cholesterol, triglycerides, VLDL-cholesterol, LDL-cholesterol, HDL-cholesterol, and especially triglyceride-rich lipoprotein remnants. Triglyceride and apo E-rich remnant-like particles (RLP) were studied as a possible risk factor for sudden cardiac death in relation to the progression of coronary atherosclerosis. The receiver-operating characteristic curve (ROC) analysis showed that RLP-TG was the most significant risk factor for sudden cardiac death among the lipids and lipoproteins and RLP-C was the best predictor for coronary atherosclerosis. HDL-C and LDL-C levels were within normal limits in the majority of the cases and did not appear to relate to the sudden cardiac death. Apo E phenotyping was performed for the detection of the genetic background in the lipid metabolism. The frequency of the Apo E3/3 (wild type) phenotype, which closely relates with the remnant metabolism, was significantly reduced in the sudden cardiac death group. Our study on the postmortem plasma lipid analysis suggested that RLP-C and RLP-TG are the best risk predictor for coronary atherosclerosis and sudden cardiac death, respectively.

Influences of laryngeal afferent inputs on intralaryngeal muscle activity during vocalization in the cat

The present study was undertaken to elucidate the possible role of the laryngeal afferent inputs in the regulation of intralaryngeal muscle activity during vocalization. We studied the influences of airflow and/or pressure applied to the larynx on intralaryngeal muscle activity during vocalization in ketamine-anesthetized cats. Vocalization was induced by airflow applied to the upper airway, which was isolated from the lower airway, during pontine call site stimulation. When the upper airway was open to the atmosphere through the nostrils and mouth, the airflow increased not only the vocal fold adductor and tensor activities but also the duration of these activities. The adductor and tensor activities were increased suddenly at a critical subglottic pressure level equivalent to the subglottic pressure threshold for vocalization. These effects were significantly reduced by sectioning of the internal branch of the superior laryngeal nerve or by lidocaine application to the laryngeal mucosa. Sustained pressure applied to the isolated upper airway, when the mouth and nostrils were occluded, did not affect adductor or tensor activities. These results indicate that the afferent inputs evoked by vocal fold stretching or vibration play an important role in the motor control of intralaryngeal and respiratory muscles during vocalization.

Single-channel properties of the nonselective cation conductance induced by neurotensin in dopaminergic neurons

Slow nonselective cation conductances play a central role in determining the excitability of many neurons, but heretofore this channel type has not been analyzed at the single-channel level. Neurotensin (NT) excites cultured dopaminergic neurons from the ventral tegmental area primarily by increasing such a cation conductance. Using the outside-out configuration of the patch clamp, we elicited single-channel activity of this NT-induced cation channel. Channel activity was blocked by the nonpeptide NT antagonist SR48692, indicating that the response was mediated by NT receptors. The channel opened in both solitary form and in bursts. The reversal potential was -4.2 +/- 1.7 mV, and the elementary conductance was 31 pS at -67 mV with [Na+]o = 140 mM, [Cs+]o = 5 mM, [Na+]i = 88 mM, and [Cs+]i = 74 mM. Thus, the channel was permeable to both Na+ and Cs+. From these characteristics, it is likely that this channel is responsible for the whole-cell current we studied previously. In guanosine 5'-[gamma-thio]triphosphate-loaded cells, NT irreversibly activated about half of the channel activity, suggesting that at least part of the response was mediated by a G protein. Similar channel activity could be induced occasionally in the cell-attached configuration by applying NT outside the patch region.

Pseudoaneurysm of the left ventricle following repair for ventricular septal perforation

The patient was a 64-year-old man who was treated surgically for an infarct-related ventricular septal perforation. Pseudoaneurysm of the left ventricle was recognized on the 38th postoperative day. Emergency surgery was performed. It seemed that insufficient resection of the infarcted myocardium was performed during the initial surgery to avoid narrowing the ventricular dimension by direct closure of the left ventricle, but this resulted in pseudoaneurysm of the left ventricle. Left ventricular free wall plasty with a patch should be performed during the initial surgery.

An explanation for inconsistency between psychophysical functions derived from different scaling methods on a prothetic continuum

In this note is proposed an hypothetical explanation for the question of why, on a prothetic continuum, a psychophysical function obtained by direct scaling is inconsistent with that obtained by indirect scaling. We explain by making the assumption that there are two stages of sensory processes which transform a given stimulus value to a perceived value serially by logarithmic and exponential functions. It is illustrated that, on a prothetic continuum, a logarithmic function should be obtained by direct scaling and a power function should be obtained by indirect scaling if our assumption is expanded mathematically.

Fatal methamphetamine poisoning in police custody

A fatal case of methamphetamine poisoning whilst in police custody is described. Drug identification and quantification in postmortem blood, urine, brain and gastric contents was achieved using gas chromatography-mass spectrometry. The blood concentration of methamphetamine was 4.92 micromol/100 g, which is in the lethal range. It is necessary for police officers to have a good knowledge of the toxic effects of abused drugs.

[A case of malignant esophageal stenosis with esophagobronchial fistula treated with a covered wallstent]

A polyurethane-covered Wallstent was used for a esophagus cancer patient with malignant esophageal stenosis associated with esophagobronchial fistula. Stent placement was successfully performed with no procedure related-complications. Following the procedure the patient could eat a normal diet. The insertion of a polyurethane-covered Wallstent is a safe and effective treatment for malignant esophageal stenosis with esophagobronchial fistula.