Efficacy of Mechanical Thrombectomy Using an Aspiration Catheter Compared with a Stent Retriever Alone for Middle Cerebral Artery M2 Occlusion

Objective

Mechanical thrombectomy (MT) for middle cerebral artery M2 occlusion (M2O) is challenging because the procedure is performed in a narrow and tortuous artery. In this study, we compared MT using an aspiration catheter (AC) versus a stent retriever (SR) used alone, and retrospectively evaluated the efficacy and safety of MT using an AC for M2O.

Methods

Seventy-four consecutive patients who underwent MT for M2O at our institution between April 2016 and April 2020 were evaluated. The subjects were classified into those treated by AC (AC group) or SR alone (SR group). The AC group included patients treated by both contact aspiration and a combination technique of AC and SR. Background factors and outcomes, including modified treatment in cerebral infarction (mTICI) 2c-3 recanalization, were compared between the groups.

Results

AC and SR groups consisted of 47 and 27 patients respectively. Among them, the rate of mTICI 2b-3 was 93.6% vs 92.6%, and that of mTICI 2c-3 was 72.3% vs 48.2% (P = 0.004). The perioperative symptomatic subarachnoid hemorrhage (SAH) rate was 0% vs 7.4%, and modified Rankin scale scores of 0-2 were 78.6% vs 50% (P = 0.03). In the AC group, the mTICI 2c-3 rate was higher in patients in whom the AC was adequately advanced to the thrombus compared to those with inadequate AC advancement (83.3% vs 36.3%, P = 0.002).

Conclusion

The rate of mTICI 2c-3 was higher in the AC than SR group, with no cases of symptomatic SAH. MT using AC for M2O might achieve safe and effective thrombectomy.

A Patient with a Delayed Diagnosis of Artery of Percheron Occlusion in Whom Thrombectomy Was Effective

Objective

A case of posterior cerebral artery (P1 segment) occlusion with consciousness disturbance and Weber's syndrome treated by mechanical thrombectomy is reported.

Case Presentation

The patient was a 69-year-old man with consciousness disturbance, left hemiparesis, and anisocoria. MRI revealed acute cerebral infarction in the midbrain and right thalamus. Angiography demonstrated that the right P1 segment was occluded and mechanical thrombectomy was performed. The right P1 segment and its perforator artery, the artery of Percheron (AOP), were both recanalized after the treatment, and the symptoms of perforator occlusion significantly improved.

Conclusion

Mechanical thrombectomy for P1 segment occlusion may be effective for improving the symptoms caused by occlusion of its perforator, the AOP.

[A Case of Thrombectomy beyond One Day after Stroke Onset Resistant to Medical Treatment]

We report a case of thrombectomy beyond one day of onset of right middle cerebral artery occlusion. An 82-year-old woman who presented with difficulty in body movements was transferred to our hospital. After admission, left-sided weakness and dysarthria worsened with an National Institutes of Health Stroke Scale of 9. The initial MRI DWI on admission revealed multiple hyper intense signals in the right cerebral hemisphere and MR angiography revealed occlusion of the right internal carotid artery. We performed medical treatment because FLAIR also revealed hyper intense signals in the same lesion as the DWI image, and more than one day had passed since the onset. However, her symptoms worsened and we performed angiography on the next day, and found contrast defects like crab claw at the top of the right internal carotid artery. Even though more than one day had passed since the onset, we assumed that thrombectomy could prevent the worsening of symptoms. The procedure was a success and it resulted in complete reperfusion to the right middle cerebral artery. She showed improvement after the procedure. According to this case, thrombectomy one day from onset could be considered as a treatment option for large vessel occlusion with good collateral flow in the cases resistant to medical treatment.

Stent-assisted coil embolization for anterior cerebral artery dissection presented with cerebral infarction

BACKGROUND

Compared to those found in the vertebrobasilar system, intracranial dissection in the anterior circulation is relatively rare, especially in the anterior cerebral artery (ACA). Moreover, only several cases of ACA dissection that underwent endovascular treatment have been reported. Here we present a rare case of gradually developing ACA dissecting aneurysm causing cerebral infarction, successfully treated by stent-assisted coil embolization.

CASE DESCRIPTION

A 36-year-old man was admitted with sudden right hemiparesis. Diffusion-weighted magnetic resonance (MR) imaging showed cerebral infarction in the left ACA territory, and MR angiography showed segmental stenosis at the A2 portion of the left ACA. Three-dimensional digital subtraction angiogram showed segmental dilatation and stenosis at the left A2 portion. We diagnosed ACA dissection causing acute cerebral infarction and treated the patient conservatively. Five months after the onset, the dissecting artery at the left A2 portion formed a gradually dilating aneurysm, suggesting increased risk for aneurysmal rupture. We attempted endovascular treatment entailing coil embolization of an aneurysm while preserving the left A2 with stent assistance. The patient remained neurologically stable 6 months after the procedure.

CONCLUSIONS

Although there are few reported cases of ACA dissection where endovascular treatment was attempted, we consider stent-assisted embolization for gradually developing ACA dissecting aneurysm as an alternative method to prevent bleeding and recurrent infarction.

Development of loop-mediated isothermal amplification assay for the detection of Pythium myriotylum

This study reports the development of a loop-mediated isothermal amplification (LAMP) reaction for the detection of Pythium myriotylum. The primer set targeting the ITS sequence of P. myriotylum worked most efficiently at 60°C and allowed the detection of P. myriotylum DNA within 30 min by fluorescence monitoring using a real-time PCR instrument. The peak denaturing temperature of amplified DNA was about 87·0°C. In specificity tests using eight Pythium myriotylum strains, 59 strains from 39 species of Pythium, 11 Phytophthora strains and eight other soil-borne pathogens, LAMP gave no cross-reactions. The detection limit was 100 fg of genomic DNA, which was as sensitive as PCR. LAMP could detect P. myriotylum in hydroponic solution samples, and the results coincided with those of the conventional plating method in almost all cases. The LAMP method established in this study is a simple and sensitive tool for the detection of P. myriotylum.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study shows the first LAMP assay for the detection of Pythium myriotylum. The primer set designed from ITS region of P. myriotylum can detect the pathogen in field sample with a fast and convenient method. Analysis of the annealing curve of the LAMP reaction products increases the reliability of the LAMP diagnosis. This study shows that the diagnostic method using the LAMP assay is useful for monitoring P. myriotylum in the field.

The surgical treatment of pyogenic spondylitis using posterior instrumentation without anterior debridement

There have been few reports regarding the efficacy of posterior instrumentation alone as surgical treatment for patients with pyogenic spondylitis, thus avoiding the morbidity of anterior surgery. We report the clinical outcomes of six patients with pyogenic spondylitis treated effectively with a single-stage posterior fusion without anterior debridement at a mean follow-up of 2.8 years (2 to 5). Haematological data, including white cell count and level of C-reactive protein, returned to normal in all patients at a mean of 8.2 weeks (7 to 9) after the posterior fusion. Rigid bony fusion between the infected vertebrae was observed in five patients at a mean of 6.3 months (4.5 to 8) post-operatively, with the remaining patient having partial union. Severe back pain was immediately reduced following surgery and the activities of daily living showed a marked improvement. Methicillin-resistant Staphylococcus aureus was detected as the causative organism in four patients.

Single-stage posterior fusion may be effective in patients with pyogenic spondylitis who have relatively minor bony destruction.

Abundance of calpain and aggrecan-cleavage products of calpain in degenerated human intervertebral discs

OBJECTIVE

To assess the expression of calpains and calpain-induced aggrecan fragmentation in early and advanced stages of degeneration of human intervertebral discs (IVDs).

DESIGN

Disc tissue samples of 55 patients (mean age, 51.2 ± 22.3 years) who underwent intervertebral fusion were divided into groups with early and advanced degeneration based on the Thompson magnetic resonance imaging (MRI) scale. In advanced degeneration group, five patients (mean age, 35.5 ± 11.4 years) of lumbar disc herniation (LDH) were included. Protein levels of m- and μ-calpains and their inhibitor calpastatin were assayed, and immunohistochemical techniques were used to localize and quantify the production of the enzymes. To investigate calpain activity, we assayed purified aggrecan fragmentation in disc tissue by Western blotting and immunohistochemistry with VPGVA antibody, which recognizes the m-calpain generated neo-epitope GVA.

RESULTS

Discs at early stages of degeneration expressed low levels of m- and μ-calpains and calpastatin, and few cells expressed degenerative enzymes. At more advanced stages of degeneration, the expression and number of cells immunopositive for m-calpain, μ-calpain and calpastatin were significantly higher. Further finding showed that anti-GVA-reactive aggrecan fragments were significantly higher in discs at advanced compared with early stages of degeneration. Herniated disc samples showed stronger expression and more cells immunopositive for calpains, calpastatin and GVA in the nucleus pulposus than in the annulus fibrous.

CONCLUSIONS

The expression of calpains, together with m-calpain-induced degradation products of extracellular matrix, was correlated with the degree of disc degeneration in human IVD tissue. These findings suggest that calpains may be involved in IVD degeneration via proteoglycan (PG) cleavage.

Sensitive and rapid detection of peach latent mosaic viroid by the reverse transcription loop-mediated isothermal amplification

A reverse transcription loop-mediated isothermal amplification (RT-LAMP) method for the detection of peach latent mosaic viroid (PLMVd) was developed. Four primer sets (OLD, OLD1, NEW, and Fukuta's) were designed originally. Based on initial experiments the set OLD1 was selected for further evaluation. Simple and accelerated RT-LAMP was preformed using degenerate and no degenerate forward-loop (F-loop) and backward-loop (B-Loop) primers. Degenerate primers were selected, and after determination of their best concentration (0.8microM), the reaction was preformed at different temperatures (60-67.5 degrees C) using three different betaine concentrations (0.8M, 0.4M, and 0.2M). Optimal conditions were found to be 62.5 degrees C and 0.8M betaine. Under these conditions, using tRNA as template, PLMVd was detected within only 32min, compared to 180min of RT-PCR, using the Real Time Turbimeter (LA200, Teramecs) which measures the turbidity caused by the production of insoluble magnesium pyrophosphate. In addition, RT-LAMP was more sensitive than RT-PCR. PLMVd was detected in peach, plum, apricot, pear, wild pear and quince samples.

Estrogen regulates the serum level of phosphorylated prolactin in mice

Phosphorylated prolactin (PPRL) is considered to be the most quantitatively important post-translationally modified form of prolactin (PRL) in rodents. We recently detected two different types of PPRL in the mouse pituitary gland; one was phosphorylated at serine and the other was phosphorylated at serine/threonine. Furthermore, we showed that there are obvious differences in the ratios between PPRLs and non-phosphorylated PRL in the pituitary gland based on age and sex and that estrogen influences PRL phosphorylation at serine in female mice. In the present study, we examined whether estradiol (E2) increases serine PPRL in the male pituitary gland in the same manner as in the female pituitary gland and examined whether PPRL is released into serum. We first determined the relative amounts of intrapituitary PPRLs in male mice under different pharmacological conditions that increased PRL secretion. The results indicated that treatment with E2 increases serine PPRL. We then performed two-dimensional electrophoresis and immunoblotting analysis after immunoprecipitation with anti-mouse PRL antibody using male and female sera under different pharmacological conditions that increased PRL secretion. The results of this experiment indicated that there were PRLs phosphorylated at serine and serine/threonine in the female serum but not in the male serum. The levels of PPRLs in sera were greatly increased with the E2 treatment for both male and female sera. Furthermore, we examined the effect of E2 on PPRL synthesis in cultured male pituitary glands. In this experiment, we observed increased serine PPRL synthesis and stronger immunohistochemical staining of PRL cells with E2 treatment. These findings suggested that serine PPRL synthesis and secretion were influenced by estrogen.

Detection of Japanese yam mosaic virus by RT-LAMP

Arapid and simple procedure is described to detect the genomic RNA molecule of Japanese yam mosaic potyvirus (JYMV). This method, named RT-LAMP, allows direct detection of RNA from infected plants without careful RNA extraction, rapid thermal cycling and gel electrophoresis. RT-LAMP was successfully applied to leaves, propagules and roots of Japanese yam infected with JYMV. One of the characteristics of the RT-LAMP method is its ability to synthesize an extremely large amount of DNA. Accordingly, a large amount of by-product, pyrophospate ion, is produced yielding a white precipitate of magnesium pyrophosphate in the reaction mixture. The presence or absence of this white precipitate allows easy detection of the amplification of JYMV genomic RNA without gel electrophoresis.

Retrovirally transduced bone marrow stromal cells isolated from a mouse model of human osteogenesis imperfecta (oim) persist in bone and retain the ability to form cartilage and bone after extended passaging

Bone marrow stromal cells isolated from a model of osteogenesis imperfecta (oim) mice, were transduced with a retrovirus (BAG) carrying the LacZ and neor genes after passage 21. The transduced cells retained the ability to express alkaline phosphatase activity in vitro when treated with recombinant human bone morphogenetic protein two (rhBMP-2), formed cartilage in vitro in aggregate cultures and formed bone in ceramic cubes after 6 weeks of implantation in nude mice. X-gal staining of ceramic cubes seeded with the transduced cells demonstrated the presence of LacZ-positive cells on the edges of bone and also in the lacunae of the newly formed bone 6 weeks after implantation. After infusion into femurs of oim mice, the transduced cells were detected in the marrow cavity and on the edges of the trabecular bone of the injected and contralateral femurs by X-gal staining and PCR analysis at 4, 10, 20, 30 and 40 days after injection. The LacZ gene was also detected in the lung and liver of the recipient mice at 4 and 10 days after injection but not at later time-periods. The present findings suggest that long-term cultured bone marrow stromal cells from osteogenesis imperfecta (OI) animals have the potential to traffic through the circulatory system, home to bone, form bone and continue to express exogenous genes. These findings open the possibility of using these cells as vehicles to deliver normal genes to bone as an alternative approach for the treatment of some forms of OI and certain other bone acquired and genetic diseases.

Identification of types II, IX and X collagens at the insertion site of the bovine achilles tendon

Achilles tendinous collagen fibrils insert into the calcaneus by first passing through a zone that is defined histologically as fibrocartilaginous. This zone consists of four regions: tendon proper, non-mineralized and mineralized fibrocartilage and bone. The function of this zone has not yet been clearly defined. To gain more insight into the role of this fibrocartilaginous zone, collagens present in the zone of the Achilles tendon-calcaneus interface were isolated and characterized. Types II, IX and X collagens were identified in the pepsin digests of the tissue harvested from the bovine Achilles tendon-calcaneus interface. Western blotting using specific antisera to types II, IX and X collagens confirmed the identity of these collagens. Immunofluorescence localization placed type X collagen predominantly in the mineralized zone of the tendon-calcaneus junction, while type IX collagen was distributed throughout the the insertion site. The presence of the cartilage-specific collagens at the Achilles tendon-calcaneus-interface suggests that this zone is cartilaginous in nature. The presence of type X collagen at this junction is not clear, but our present findings go along with the previous report which showed that type X collagen is present in the mineralized zone of the medial collateral ligament femoral insertion site. These data suggest that type X collagen may be a resident of mineralized fibrocartilaginous zones of tendon or ligament-bone junctions and may participate in anchoring ligament or tendon to bone.

Morphological studies on middle ear barotrauma in guinea pigs

Experimental middle ear barotrauma was studied morphologically. White guinea pigs were placed in an experimental hyperbaric chamber, and middle ear barotrauma was created by increasing the pressure in the hyperbaric chamber from 1 atmosphere absolute (ATA) to 2 ATA using pure oxygen, maintaining the pressure at 2 ATA for 10 minutes, then again reducing the pressure to 1 ATA. Selected experimental animals were decapitated immediately after, one day after, one week after, or weeks after pressure loading, and their middle ears were examined by a light microscope (LM), a scanning electron microscope (SEM) and a transmission electron microscope (TEM). Hemorrhaging in the tympanic cavity immediately after pressure exposure was apparent even macroscopically. LM also revealed evidence of submucous hemorrhage. Submucous edema was seen in the "one week after" cases. SEM showed a minor loss of cilia in some ciliated cells just after the experiment. In nonciliated cells, the terminal web was somewhat indistinct in the "one week after" cases. TEM also indicated a minor loss of cilia in some ciliated cells in "one day after" cases as well as apparent vacuoles within the cells. These findings suggest that although trauma during compression is more marked than during decompression, recovery from this damage progressed with time.

[A case of lupus myocarditis and nephritis with transient foramen jugular syndrome]

A 46-year-old man was admitted to our clinic because of acute heart failure. Six years before admission he was pointed out cardiomegary and hematuria. One year later, he was diagnosed as having jugular foramen syndrome. On admission, he had a fever and dyspnea. Pansystolic blowing murmur was audible at the apex. The chest ratio on his chest X-ray was 52.5%. An electrocardiogram showed left ventricular hypertrophy. An echocardiogram showed marked dilatation and severe dysfunction of left ventricle. Radionuclide scanning with technetium 99 m pyrophosphate identified inflammatory change in the apex. Myocardial biopsy showed fibrotic degeneration and IgG deposits in myocardium. Blood examination showed anemia, lymphopenia. positive anti-nuclear antibody (1000 times, shaggy pattern), positive anti ds-DNA antibody and hypocomplementemia. Furthermore, proteinuria was pointed out. Renal biopsy showed focal segmental glomerulonephritis with active necrotizing lesion (type III nephritis). Lupus myocarditis and nephritis was diagnosed. After prednisolone (80 mg/day) was administered. left ventricular function and hypocomplementemia improved. The ACE inhibitor was also used for proteinuria. In spite of a little amount of blood transfusion, he showed hepatic hemosiderosis. We suspect that the cause of hemosiderosis was related chronic inflammation of active lupus. It was treated with Erythropoietin.

A case of pleomorphic adenoma of the epiglottis. Bilateral vocal-cord paralysis after YAG laser surgery

Pleomorphic adenoma of the larynx is a rare disorder, and until recently has been treated mainly by approaches involving pharyngotomy. We encountered a case of pleomorphic adenoma originating from the laryngeal surface of the epiglottis and removed it using a YAG laser through a suspension laryngoscope. This case was complicated by delayed-onset bilateral vocal-cord paralysis, the causes of which are also discussed.

Application of a new anticoagulant (Nafamostat Mesilate) to control hemorrhagic complications during extracorporeal membrane oxygenation--a preliminary report

Bleeding related to systemic heparinization has been considered one of the major complications associated with extracorporeal membrane oxygenation (ECMO). Development of the heparin-bonded system will be essential in reducing hemorrhagic complications, but has not yet been clinically proven. The authors chose an alternative approach of making a difference in the activated clotting time (ACT) values between the patient and the ECMO circuit, and decreased only the patient's ACT value, while keeping the value of the ECMO circuit at an ideal level. For this purpose, we have used a very short-life anticoagulant, Nafamostat Mesilate (FUT), while decreasing the dose of heparin. FUT is a synthetic protease inhibitor that has been found to inhibit various kinds of enzyme activities for coagulation. Twelve newborns who had some hemorrhagic complications at various sites before or during ECMO, were selected to receive FUT. The heparin dose was decreased after FUT administration into the drainage route. FUT and heparin doses were regulated to maintain the ACT value at the reinfusion route at 190 to 220 seconds. ACT values at the drainage and the reinfusion routes were simultaneously measured. The average time on FUT was 100.3 +/- 86.3 (SD) hours. The average dose of FUT was 0.48 +/- 0.22 mg/kg/h, and that of heparin was 21.0 +/- 7.5 U/kg/h. The average ACT value at the reinfusion route was 205.7 +/- 14.0 seconds compared with that at the drainage route of 178.5 +/- 11.8. The difference was statistically significant (P < .001). The average difference in ACT values between both routes was 27.1 +/- 7.9 seconds. The bleeding was well controlled by FUT administration in 8 of 12 cases. This report may represent the first clinical use of FUT in neonatal ECMO, and serve as a preliminary study.

Inner ear disorders due to pressure change

We reviewed the records of 136 patients who had inner ear disorders including hearing loss and vertigo caused by pressure change. We divided them into three groups, according to the aetiology: group A, change in atmospheric pressure (diving, airplane travel, etc.); group B, rapid change in ear pressure in normal atmosphere (nose blowing, heavy lifting, etc.); and group C, blast injury. A flat initial audiogram was the most common type in groups A and B. In group C, high-tone hearing loss was the most common type of audiogram. These results correspond to findings previously reported in animal experiments. Exploratory tympanotomy was performed more than 12 days after the pressure change in 16 patients. Although the vertigo disappeared after surgery, hearing did not improve.

Autoimmune response in chronic ongoing myocarditis demonstrated by heterotopic cardiac transplantation in mice

BACKGROUND

Autoimmune mechanisms have been implicated in the pathogenesis of chronic ongoing myocarditis. To investigate this relation, we used an A/J mouse model inoculated with coxsackievirus B3 and determined whether myocarditis would be transferred to normal hearts that were heterotopically transplanted.

METHODS AND RESULTS

Inbred 3-week-old A/J mice were inoculated intraperitoneally with coxsackievirus B3 (Nancy strain; 2 x 10(4) plaque-forming units) and housed for > 60 days. The presence of the viral genome in the myocardium was determined by the polymerase chain reaction with primers specific for the 5' end of the coxsackievirus B3 genome performed at 40, 50, or 60 days after inoculation. Normal A/J mouse hearts were transplanted into the same strain of mice without myocarditis (group A) and into mice with chronic ongoing myocarditis (group B). The hearts were evaluated histologically 2 weeks after transplantation. Conventional histological examination of infiltrated T cells and macrophages was performed, and the expression of intercellular adhesion molecule-1, major histocompatibility complex (MHC) class I antigen, and MHC class II antigen was evaluated by immunoenzymatic staining. The concentrations of interleukin-1 alpha (IL-1 alpha) and tumor necrosis factor (TNF-alpha) in the grafts were measured with an ELISA. The viral RNA genomes were not detected in the mice with chronic ongoing myocarditis, but their transplanted hearts did show myocarditis. In the hearts with induced myocarditis, infiltrated mononuclear cells consisted of CD4+ T cells, CD8+ T cells (CD4+ cell number > CD8+ cell number), and macrophages. Intercellular adhesion molecule-1, MHC class I antigen, and MHC class II antigen were expressed in the vascular endothelial cells and myocardial cells in and around the infiltrated lesions. The concentrations of IL-1 alpha and TNF-alpha in group B were significantly higher than those in group A (group A versus group B: IL-1 alpha, 125 +/- 35 versus 180 +/- 34 pg/mL; TNF-alpha, 45 +/- 15 versus 96 +/- 40 pg/mL; P < .05).

CONCLUSIONS

Results suggest that an autoimmune response may play a key role in the progression of chronic ongoing myocarditis.

A pathogenic mechanism of chronic ongoing myocarditis

To clarify the pathogenetic mechanism of chronic ongoing myocarditis, we produced Coxsackievirus B3-induced myocarditis in A/J mice and immunopathologically examined the microcirculation in the chronic phase of myocarditis. Forty-two 3-week-old A/J mice were inoculated intraperitoneally with Coxsackievirus B3 (Nancy strain) 2 x 10(4) PFU (plaque-forming units) and sacrificed 7, 14, 21, 50, 90, or 120 days later. To evaluate myocardial microcirculation, 18 of the hearts were perfused from the thoracic aorta with warm 2% gelatin/carbon solution. The remaining hearts were quickly frozen for immunologic analysis with an enzyme immunostaining assay using monoclonal antibodies against CD4, CD8, macrophages, intercellular adhesion molecule-1 (ICAM-1) and major histocompatibility complex class I or II. The presence of viral RNA genome in the myocardium at 40, 50, or 60 days after inoculation was evaluated using the polymerase chain reaction. The lesions in chronic ongoing myocarditis consisted of myocardial damage, myocardial calcification, interstitial fibrosis, and infiltration of mononuclear cells. These infiltrated lymphocytes were predominantly CD4+ T cells. Furthermore, microvascular abnormalities, including dilatation, tortuosity, constriction, and abrupt termination, were observed around the lesions. There was marked infiltration by mononuclear cells around the microvessels. ICAM-1 was strongly expressed in the endothelial cells of the vessels. Coxsackie B3 viral genome was not detected in the myocardium of mice with chronic ongoing myocarditis in each stage examined. These results suggest that an autoimmune mechanism is involved in the persistent inflammation seen in chronic ongoing myocarditis.

[Scanning electron microscopic study of inner ear barotrauma: in the guinea pig under hypobaric pressure]

In order to investigate the mechanism of inner ear barotrauma, guinea pigs, with bilateral eustachian tube occlusion, were subjected to decompression and compression between 760 and 460 mmHg in a hypobaric pressure chamber. We divided the guinea pigs into two groups, A and B. Group A showed normal eustachian tubes, and group B showed bilaterally occluded eustachian tubes. Group B animals were divided into three types according to the rates of compression and decompression. After pressure loading, morphological changes in the hair cells of the organ of Corti were studied by means of scanning electron microscopy. There was no damage to hair cells in the setting of normal eustachian tube function, as in group A. On the other hand, mild to severe hair cell damage was observed with rapid decompression in group B. This observation suggests that relative positive pressure in the middle ear cavity is an important factor in inner ear barotrauma. The mechanism of hair cell damage due to inner ear barotrauma is presumed to be distortion of the organ of Corti caused by a difference in pressure between perilymph and endolymph resulting in injury to the stereocilica.

[Vestibular changes due to barotrauma]

Morphological vestibular changes caused by barotrauma were studied in guinea pigs. Animals were exposed to rapid decompression from 2 absolute atmospheric pressures (ATA) to 1 ATA, which causes inner ear barotrauma in the guinea pig. During decompression, spontaneous nystagmus was recorded, which consisted of irritative symptoms initially, followed by paralytic nystagmus. After pressure loading and observation to confirm the absence of Preyer's reflex with vertigo, the animals were tested for caloric nystagmus using ice water and then sacrificed at varying intervals. Then, morphological changes in vestibular organs and the organ of Corti were studied. Half of the experimental animals showed canal paresis on caloric testing. Damage to the organ of Corti was severe while that to vestibular organs was very slight. Damage to the sensory cells of the vestibular organs was not clear on light microscopy, despite a partial collapse of labyrinthine membranes. Under scanning electron microscopy, local damage was observed in a portion of the crista ampullaris of the semicircular canals. In this area, incomplete or complete disappearance of kinocilia and stereocilia, similar to that seen after rotatostimulation, was observed. However, no damage to sensory hairs was seen in the utricles and saccules. The observed vestibular organ damage, resulting from inner ear barotrauma, suggested effects on endolymphatic flow.

Dilated cardiomyopathy with special reference to humoral immunity

The question of whether the etiology of DCM is immune or autoimmune has been increasingly discussed. Abnormal findings on humoral immunity in DCM were investigated, especially those regarding anti-heart antibodies (AHA), IgG subclasses and soluble interleukin-2 receptor (sIL-2R). The heterophile type AHA was detected in 64.7% of cases by the indirect immunofluorescence technique (IF) with rat heart, by indirect IF with human heart AHA in 57.8% of cases, and by thin-layer chromatogram with human glycolipids AHA in 44% of cases. Also, 57.1% of the specimens were found to bind IgG on perimyocytes by direct IF with biopsy specimens taken from patients with DCM. The epitope of an antigen which reacted with the heterophile type AHA is a Gal alpha 1-3Gal structure. 200 Kd, 70 Kd and 40 Kd antigens were reacted with AHA detected by indirect IF with human heart. The possible mechanisms of AHA in the pathogenesis could be either complement dependent cytotoxicity or interference to cardiac metabolism. The concentration of sIL-2R and IgG3 in sera from patients with DCM were elevated. These results suggest that immunological abnormalities occur continuously in DCM.

[Magnified tomography for identification of ceramic prostheses]

Recently, ceramic prostheses for ossicular replacement have become very popular in middle ear surgery. These prostheses have a good affinity with the surrounding tissue. But, it is difficult to identify the position of these prostheses postoperatively. We used magnified tomography in order to identify the implanted ceramic prostheses, and to determine whether these prostheses were in the appropriate position. In the case of patients without stapes, we usually use Apaceram type T, which restores ossicular continuity to the inner ear. When the shaft of the ceramic prosthesis is placed on the oval window niche, the overhanging Fallopian canal obstructs the tip of the prosthetic shaft to obtain the appropriate place in the oval window. The angle of the shaft should be slightly tilted inferiorly against the medial wall of the middle ear cavity.

Genetic Analysis of Dilated Cardiomyopathy. HLA and immunoglobulin genes may confer susceptibility

To identify genetic factors in the immune system which control the susceptibility to dilated cardiomyopathy (DCM), HLA class II DNA typing was performed in 61 Japanese patients, using PCR/SSO probe analyses. The frequencies of HLA-DQB1*0503 (15% vs 5%; RR = 3.06, chi 2 = 7.19) and DQB1*0604 (21% vs 10%; RR = 2.41, chi 2 = 6.20) were significantly increased and that of HLA-DQB1*0502 (RR = 1.74) was slightly increased in the DCM patients. The frequency of DQB1*0303 (16% vs 31%; RR = 0.44, chi 2 = 5.16) was significantly decreased in the patients. The increased HLA-DQB1 alleles have a histidine residue in common at the 30th codon for the HLA-DQ beta chain. Among the genetic markers studied by Southern blot analyses, IGLV (immunoglobulin lambda light chain, pV3.3) showed a strong association with DCM, i.e. A2/A2 genotype was found in 37.7% of patients whereas it was observed in only 18.9% of the control subjects (RR = 2.6, chi 2 = 7.77). The frequency of this genotype was higher in patients under age 45 years at the time of diagnosis (45.5%, RR = 3.6, chi 2 = 10.02). These results suggest that HLA and immunoglobulin genes are closely linked to susceptibility to DCM.

Effects of persistent perilymph fistula on the inner ear

To study the effects of a persistent perilymph fistula on the cochlea, a small cannula was inserted into the scala tympani of the basal turn of cochlea in guinea pigs. A month later, cochlear morphology and blood flow were studied using either histological evaluation or the microsphere surface preparation technique. Some animals showed no cochlear morphologic changes or no cochlear blood-flow reduction, even if tubal patency was maintained and perilymph leakage lasted for 1 month. This suggests that a prolonged perilymph fistula, per se, causes no permanent cochlear damage. However, in some animals, hair cell damage and cochlear blood-flow disorders were observed. These observations and the causes of hearing loss in clinical cases of perilymph fistula were studied.

[A case of polyangiitis overlap syndrome]

A 25 year old man was admitted to our hospital on June 1, 1989 because of general fatigue and pleural effusion. He had noticed purpuras and nodules on his bilateral lower legs in July 1988. He was admitted to Nihon University Hospital and was diagnosed as allergic granulomatous angiitis. Methylprednisolone was administered. In March, 1989, a nodular shadow was detected in his lung CT films. From the findings of TBLB a granulomatous lesion was suspected. However, his clinical course was rather stable so he was discharged from the hospital. Two months later, he was suffered from fever and general fatigue. On his chest X ray film pleural effusion was detected in the lower part of his left lung. The nodular shadow was increasing gradually. Laboratory findings on his admission showed leukocytosis, thrombocytosis, elevated CRP and a high titer of RA factor. He was diagnosed as hypersensitivity angiitis in a broad sense based on his biopsy findings of the skin lesion. Furthermore, the diagnosis of an early stage of Wegener's granulomatosis (WG) or limited type of WG was also made from the clinical course of his lung lesion. The combination therapy with cyclophosphamide and methylprednisolone was started. It was so effective that the nodule of his left lung was almost disappeared. It seems that this case is one of the polyangiitis overlap syndrome proposed by Fauci.

[Electron microscopic study on inner ear barotrauma: with emphasis on the cochlear damage]

In order to investigate inner ear barotrauma, guinea pigs were subjected to rapid decompression between 2 absolute pressure (ATA) and 1 ATA in a chamber. After pressure loading and observation for absence of Preyer's reflex, they were sacrificed immediately, 1 day, 1 week and 1 month later, respectively. Then, morphological changes of the organ of Corti and stria vascularis were studied under TEM and SEM. The immediate features noted were fracture of stereocilia with minimal intracellular changes. One day later, there was marked degeneration of outer hair cells and expansion of supporting cells. The damage to stereocilia clearly preceded morphological alterations within hair cell bodies and cannot be interpreted as arising secondary to hair cell degeneration. Most of outer hair cells eventually disappeared and were replaced by supporting cells. Inner hair cells degenerated slowly; 1 month later, some of them remained almost intact, despite disappearance of stereocilia. The continuity of reticular lamina was maintained not only immediately but also through the period of hair cell degeneration, thus preventing any leakage of endolymph into the organ of Corti. There was reversible dendritic swelling of inner hair cells immediately following the trauma. No changes of stria vascularis were observed over passage of time. The mechanism of hair cell damage due to inner ear barotrauma is presumed to be a deformity of the organ of Corti caused by pressure discrepancy between perilymph and endolymph resulting in an injury to stereocilia.

[Morphological study of cochlea in experimental chronic serum sickness]

Relationship of circulating immune complexes to some inner ear disorders has been suggested recently. Thus, bovine serum albumin (BSA) nephritis, a model of chronic serum sickness, was made and morphological, immunological studies of cochlea were performed using light microscopy, transmission electron microscopy and immunofluorescent antibody methods. Group 1 consisted of animal sensitized with daily BSA injections for 90 days; in group 2, BSA was administered for 70 days, daily, and after a three-weeks interval, injections were continued for another 21 days; group 3 consisted of animals sensitized with daily BSA injections for 100 days followed by BSA injection into the facial nerve via the stylo-mastoid foramen. The animals (group 3) were sacrificed on day 1 and 4 following facial nerve sensitization for examination of cochlear morphological changes. No morphological changes were observed (group 1). Protrusion of marginal cells into endolymphatic space was seen, because of swelling of endoplasmic reticulum of the cells of stria vascularis's (group 2). Slight hydrops was present mainly in the basal turn (group 3). No IgG deposits were found in all groups. It appears that the changes in group 2 were caused by rather chronic nephritis than immune reaction. We conclude that damage induced in the cochlea is negligible compared to the extensive lesions observed in the kidney in chronic serum sickness.

Spectral analysis of airflow sounds in patent versus occluded tracheostomy tubes: a pilot study in tracheostomized adult patients

Cannula occlusion is a life-threatening postoperative complication of tracheostomy. Current management largely relies on nursing care for prevention of fatalities because no proven mechanical, machine-based support monitoring exists. The objective of this paper was to address the problem of monitoring the state of cannula patency, based on analysis of airflow acoustic spectral patterns in tracheostomized adult patients in the patent and partially occluded cannula. Tracheal airflow sounds were picked up via a condenser microphone air-coupled to the skin just below the tracheal stoma. Signal output from Mic was amplified, high-pass filtered, digital tape-recorded, and analyzed on a mainframe computer. Although airflow frequencies for patient cannulae were predominantly low-pitched (0.1 to 0.3 kHz), occluded tubes had discrete high-pitched spectral peaks (1.3 to 1.6 kHz). These results suggest that frequency analysis of airflow sounds can identify a change in the status of cannula patency.

Hemodynamic benefits of long-term bunazosin (alpha-1 blocker) therapy in rats with myocardial infarction and heart failure

To determine whether bunazosin (alpha 1-adrenoceptor blocking agent) can alter the hemodynamic profile of chronic heart failure secondary to myocardial infarction, the drug was administered to Wistar rats 4 weeks after coronary ligation, and continued for 4 weeks. In rats without bunazosin treatment, the left ventricular end-diastolic pressure (LVEDP) and the total vascular resistance index (TVRI) increased as a function of infarct size, while the cardiac index (CI) decreased. But in infarcted rats with bunazosin treatment, the mean aortic pressure and TVRI were reduced, the LVEDP was modestly lessened, and the CI was maintained. The greatest increase in CI after the treatment occurred in rats with infarcts of small and moderate size. Thus, long-term therapy with bunazosin improved LV dysfunction, relative to the size of infarction. This study suggests the beneficial effects of bunazosin therapy in patients with chronic heart failure.

Comparison of the carbohydrate-binding specificities of cholera toxin and Escherichia coli heat-labile enterotoxins LTh-I, LT-IIa, and LT-IIb

The heat-labile enterotoxins of Vibrio cholerae and Escherichia coli are related in structure and function. They are oligomers consisting of A and B polypeptide subunits. They bind to gangliosides, and they activate adenylate cyclase. The toxins form two antigenically distinct groups; members of each group cross-react but are not necessarily identical. Serogroup I includes cholera toxin (CT) and type I heat-labile enterotoxin (LT-I) of E. coli. LTh-I and LTp-I are antigenic variants of LT-I produced by strains of E. coli from humans and pigs, respectively. Serogroup II contains the type II heat-labile enterotoxin (LT-II) of E. coli. Two antigenic variants designated LT-IIa and LT-IIb have been described. The binding of CT, LTh-I, LT-IIa, and LT-IIb to gangliosides was analyzed by immunostaining thin-layer chromatograms and by solid-phase radioimmunoassay. The four toxins have different glycolipid-binding specificities. LTh-I and CT bind strongly to ganglioside GM1 and less strongly to ganglioside GD1b. However, LTh-I, unlike CT, also binds weakly to GM2 and asialo GM1. LTh-I, like CT, probably binds to the terminal sugar sequence Gal beta 1-3GalNAc beta 1-4(NeuAc alpha 2-3)Gal . . ., where GalNAc is N-acetylgalactosamine and NeuAc is N-acetylneuraminic acid. LT-IIa probably binds to the same sugar sequence to which CT and LTh-I bind, with the additional contribution to binding of a second NeuAc as in GD1b and GD2. Also, LT-IIa must bind the Gal beta 1-3GalNAc . . . sequence in such a way that its binding is relatively unaffected by attachment of NeuAc to the terminal galactose residue as in GD1a, GT1b, and GQ1b. LT-IIb probably binds to the terminal sugar sequence NeuAc alpha 2-3Gal beta 1-4GalNAc . . ., as it binds to gangliosides GD1a and GT1b but not to GM1.

Study of immunological mechanism in dilated cardiomyopathy

To determine the immune disturbances involved in the pathogenesis of dilated cardiomyopathy (DCM), the conditions in humoral and cellular immunity of DCM patients were studied. To examine the status in humoral immunity in DCM patients, circulating anti-heart antibodies (AHAbs) were analyzed. Circulating-AHAbs were classified into 4 types "heterophile-like", "intracellular", "intercalated disc" and "nuclear" patterns by indirect immunofluorescence technique, and a high rate of heterophile-like antibody was found in DCM. The cytotoxicity of this antibody was examined in cultured myocardial cells using the two-step method of the complement dependent cytotoxic test. The mean cytotoxic index (CI) value of the heterophile-like antibody positive sera was 22.3, which showed an apparent cytotoxicity against the cultured cells and it may be complement dependent. In addition, the frequency of lymphocyte subsets using monoclonal antibodies (OKT4, OKT8, Leu7, Leu11) and natural killer (NK) activity were evaluated to determine whether DCM patients had an imbalance in cellular immune reactions, which support the hypothesis of an immune disturbance as the pathological mechanism of DCM. The peripheral lymphocyte counts were significantly lower in patients with DCM (1737 +/- 874/mm3) than in normal controls (NC, 2088 +/- 556/mm3) and in patients with ischemic heart diseases (IHD, 2395 +/- 469/mm3, both p less than 0.01). The percentage of T, B, OKT4 and OKT8 positive cells was not statistically different among DCM, IHD, and NC groups, whereas the percentage of T gamma cells was significantly reduced in DCM patients (6.5 +/- 5.0%, p less than 0.05). NK functional activity as tested in DCM patients was frequently deficient (24.1 +/- 16.7% in DCM, 36.7 +/- 12.2% in NC). After 4-hr incubation with recombinant interleukin2 (rIL2), rIL2 induced the enhancement of NK activity in 3 out of 4 DCM patients with low NK activity, although, there was a non-responder to rIL2 in this group. These results suggested that DCM patients have a low IL2 production and/or less numbers of mature cells with NK cell function. Therefore, an imbalance in humoral and cellular immune reactions may cause insidious myocardial damage and subsequently lead to development of DCM.

Monoclonal antibody CC3C195, which detects cancer-associated antigens in serum, binds to the human Lea blood group antigen and to its sialylated derivative

Mouse monoclonal antibody CC3C195, which detects elevated levels of its antigen in sera from many patients with colon and pancreatic cancer, binds with high affinity to the sialylated human Lea blood group antigen NeuAc alpha 2-3Gal beta 1-3 [Fuc alpha 1-4]GlcNac . . . and with lower affinity to the Lea blood group antigen itself.

Monoclonal antibody Leo Mel 3, which inhibits killing of human melanoma cells by anomalous killer cells, binds to a sugar sequence in GD2 (II3(NeuAc)2-GgOse3Cer) and several other gangliosides

Human anomalous killer (AK) cells lyse freshly isolated human melanoma cells which are insensitive to human natural killer cell-mediated lysis. Monoclonal antibody Leo Mel 3, an IgM (k), produced by a hybridoma obtained from a mouse immunized with human melanoma cells, binds to melanoma cells and inhibits their conjugate formation with AK cells as well as their AK cell-mediated lysis. Other IgM antibodies from the same fusion that bind melanoma cells do not inhibit (Werkmeister, J. A., Triglia, T., Andrews, P., and Burns, G. F. (1985) J. Immunol. 135, 689-695). Leo Mel 3 binds several different gangliosides from melanoma cells, as determined by immunostaining thin layer chromatograms. Binding is abolished by treatment of the gangliosides with neuraminidase. In solid-phase radioimmunoassay, Leo Mel 3 binds strongly to ganglioside GD2 and less strongly to gangliosides GT3, GD3, and GQ1b. It does not bind to other gangliosides including GM1, GM2, GM3, GD1a, GD1b, and GT1b. Thus, the epitope recognized by antibody Leo Mel 3 is found in the sugar sequence of ganglioside GD2, GalNAc beta 1-4[NeuAc alpha 2-8NeuAc alpha 2-3]Gal beta 1-4Glc beta 1 .... This sequence may contain a target in melanoma cells recognized by AK cells.

Study on lymphocyte subsets and NK cell function in patients with dilated cardiomyopathy

An acquired defect or damage of a subpopulation of suppressor T lymphocytes is reported in connection with autoimmune diseases. In the present study, the role of immunity was examined in 7 patients with dilated cardiomyopathy (DCM). The frequency of lymphocyte subsets using monoclonal antibodies and natural killer (NK) cell activity was evaluated to determine whether DCM patients had lymphocyte abnormalities that would support the hypothesis that the pathological mechanism of DCM is an immune disturbance. The peripheral lymphocyte counts were significantly lower in patients with DCM and higher in patients with ischemic heart disease (IHD) than in normal controls (NC) (p less than 0.01). The percentage of T cells, B cells, OKT4 and OKT8 positive cells was not statistically different among the three groups studied here, whereas the percentage of T gamma cells was significantly reduced in DCM patients (p less than 0.05). NK cell functional activity as tested in DCM and IHD patients was frequently deficient (22.1 +/- 19.3% in DCM, 13.8 +/- 3.0% in IHD, 37.4 +/- 12.7% in NC). Our results suggest that an imbalance in cellular immune reactions partly explain the pathogenesis of DCM.

Immunological study of heart diseases with special reference to the cytotoxicity of the heterophile antibody against cultured myocardial cells

In our previous study, a high rate of "heterophile antibody" was found in idiopathic cardiomyopathy. In the present investigation the cytotoxic activity of this antibody was examined in cultured myocardial cells. Trypsin treated cells cultured for 3 days were used in the two-step method of the complement dependent cytotoxicity test. The trypan blue dye-exclusion method was utilized to determine the percentage of surviving cells, and the cytotoxic effect was expressed by the cytotoxic index (CI). With fresh rabbit serum as complement, the mean CI value of the heterophile antibody positive sera was 20.7, which was in contrast to the value of anti-heart antibodies negative sera (p less than 0.01). As the cytotoxic effect to the heterophile antibody was absent without the complement, it may be complement dependent. Thus, our results suggest that the heterophile antibody may play a role in the pathogenesis or be an incremental factor of idiopathic cardiomyopathy.

Circulating anti-heart antibodies in heart diseases detected using an immunofluorescent technique

Circulating anti-heart antibodies (C-AHAb) were examined in the sera of 132 patients with heart diseases and of 65 normal healthy controls using an indirect immunofluorescent technique. The patient groups consisted of 31 with dilated cardiomyopathy, 22 with hypertrophic cardiomyopathy, 38 with myocardial infarction, 15 with angina pectoris and 26 with rheumatic valvular disease. The indirect immunofluorescent staining patterns were classified into 4 types: "heterophile", "intracellular", "intercalated disc" and "nuclear" patterns. The positive incidence of C-AHAb was 81% in dilated cardiomyopathy, 77% in hypertrophic cardiomyopathy, 65% in rheumatic valvular disease, 58% in myocardial infarction, 40% in angina pectoris and 39% in normal healthy controls. A high rate of "heterophile" antibodies was found in the idiopathic cardiomyopathy group: 65% in dilated cardiomyopathy and 55% in hypertrophic cardiomyopathy. The intracellular staining pattern was present in 42% of rheumatic valvular disease. These findings suggest that positive C-AHAb and staining patterns may be useful in the assessment of the pathogenesis of certain types of heart diseases.

Experimental myocarditis. II. Cardiac lesions in rats induced by immunization with heterologous heart extracts

The production of myocardial lesions and circulating anti-heart antibodies has been studied in the present experiment. Twenty-one of Wistar rats were divided into 3 groups: 9 rats immunized with heterologous heart extracts, Freund's complete adjuvant and diphtheria-tetanus-pertussis (DTP) vaccine, 8 rats injected phosphate buffered saline adjuvant mixture with DTP vaccine and 4 rats untreated as control. Injection of heterologous heart extracts emulsified with Freund's complete adjuvant and DTP vaccine developed focal myocardial lesions in all of the subjected rats. The lesions were characterized by focal and diffuse interstitial cellular infiltration with myocardial necrosis. The circulating antibodies reacted to rat heart extracts were detected in 77.8% of the subjects. The antigen, reacted with the antibodies, located intracellular spaces in myocardium. The severity of cardiac lesions were not functional to the titer of circulating anti-heart antibodies may play little role in the pathogenesis of myocardial damage at least in this experimental myocarditis.

Experimental myocarditis. I. Cardiac lesions in rats induced by immunization with homologous heart extracts

The production of myocardial lesions and circulating anti-heart antibodies has been studied in rats injected with homologous heart extracts emulsified with the Freund's complete adjuvant and the DTP vaccine. Six of 7 rats showed lesions of focal myocarditis, while only in one of them circulating anti-heart antibodies were detected. There was no correlation between the presence of circulating anti-heart antibodies and that of myocardial lesions. These findings suggested that the circulating anti-heart antibodies may play little or no role in the pathogenesis of this experimental myocarditis.

Analysis of the heart antigens. Homologous and heterologous anti-heart antibodies and analysis of the heart specific antigens

The present study has indicated the presence of 3 heart specific antigens, using homologous and heterologous antibodies produced in immunized rabbits. Two of these antigenic proteins exhibit restricted organ specificity for heart and the other one shares by heart and kidney. One of these 2 heart specific antigens reacts to both homologous and heterologous anti-heart sera absorbed with kidney, while the other reacts to only heterologous anti-heart sera. The former has an electrophoretic mobility corresponding to that of serum beta-globulin, and is found to have a molecular weight of about 175,000. The latter has the same electrophoretic mobility as that of alpha2-globulin and is found to have a molecular weight of about 50,000.