Outcome of extracorporeal membrane oxygenation use in severe accidental hypothermia with cardiac arrest and circulatory instability: A multicentre, prospective, observational study in Japan (ICE-CRASH study)

AIM

To elucidate the effectiveness of extracorporeal membrane oxygenation (ECMO) in accidental hypothermia (AH) patients with and without cardiac arrest (CA), including details of complications.

METHODS

This study was a multicentre, prospective, observational study of AH in Japan. All adult (aged ≥18 years) AH patients with body temperature ≤32 °C who presented to the emergency department between December 2019 and March 2022 were included. Among the patients, those with CA or circulatory instability, defined as severe AH, were selected and divided into the ECMO and non-ECMO groups. We compared 28-day survival and favourable neurological outcomes at discharge between the ECMO and non-ECMO groups by adjusting for the patients' background characteristics using multivariable logistic regression analysis.

RESULTS

Among the 499 patients in this study, 242 patients with severe AH were included in the analysis: 41 in the ECMO group and 201 in the non-ECMO group. Multivariable analysis showed that the ECMO group was significantly associated with better 28-day survival and favourable neurological outcomes at discharge in patients with CA compared to the non-ECMO group (odds ratio [OR] 0.17, 95% confidence interval [CI]: 0.05-0.58, and OR 0.22, 95%CI: 0.06-0.81). However, in patients without CA, ECMO not only did not improve 28-day survival and neurological outcomes, but also decreased the number of event-free days (ICU-, ventilator-, and catecholamine administration-free days) and increased the frequency of bleeding complications.

CONCLUSIONS

ECMO improved survival and neurological outcomes in AH patients with CA, but not in AH patients without CA.

OP0238 CLINICAL ANALYSIS OF 34 CASES OF CARDIAC COMPLICATIONS REQUIRING SURGICAL INTERVENTION IN SYSTEMIC LUPUS ERYTHEMATOSUS AND ASSESSMENT ABOUT MECHANISM OF DEVELOPMENT WITH IMMUNOLOGICAL ANALYSIS

Background

In cases of systematic lupus erythematosus (SLE) that lead to surgery due to the development of heart diseases such as valvular disease, ischemic heart disease and aortic aneurysm, early detection and careful monitoring are important. An absence of background diseases or immunopathological examination of the myocardial tissue in SLE cases with cardiovascular lesions demonstrates the lack of knowledge in this area. In recent years, however, there have been reports of neutrophil extracellular traps being involved in the fulminant onset of SLE.

Objectives

This study aimed to analyze clinically and immunohistopathologically the pathophysiology of heart diseases associated with SLE.

Methods

We performed left atrial appendage resection in 34 patients, including patients with cardiovascular lesions, who underwent heart surgery for SLE complications from 2012 to 2021. Tissue analysis was conducted in 9 cases. The left atrial appendage, in cases of non-collagen valvular disease, was used as the control. Tissue staining of cardiomyocytes was carried out by adding anti-neutrophil extracellular(NE) antibodies(Abs) to anti-human IgG antibody (Ab), anti-IgM Ab and anti-C3 Ab.

Results

Of the 34 SLE patients 14 had valvular disease, 8 had ischemic heart disease and 12 had aneurysms. Preoperative SLE activity was relatively stable with only 1 patient below the CH50 standard and 6 patients above the anti-DNA Ab standard. The Ab positivity rate for the patients in this study was higher than that of the 687 SLE patients who were previously tested in 2019. The presence of anti-CL Abs was 55.6%, which was higher than the 25.5% observed in previous SLE patients. In this study, anti-SS-A and anti-RNP Abs tended to be relatively numerous. An example of immunohistochemical staining of IgG in the left atrial appendage is presented (Figure 1a). IgG deposits were not observed on the left side of the myocardial fibers in the control group, whereas IgG deposits were observed on the right side in the SLE group. Deposits were also observed in tissues that were not located in the affected areas. The presence or absence of tissue deposition in the myocardial fibers and clinical findings in 2 cases of the control group and 9 cases of the SLE complication group are reported in Table 1. IgG deposits were found in the myocardial fibers of 6 of the 9 patients in the SLE complication group, and deposits were found in the left atrial appendage tissue regardless of the type of heart disease, suggesting a potential change in the heart tissue. In the SLE group, 5 cases were positive for antiphospholipid (APS) Abs, while 7 cases were positive for either anti-SS-A or anti-RNP Abs. Only 2 cases had elevated preoperative anti-DNA Ab and complement reduction. Of the SLE complication group, 2 of the 9 cases were negative for all Abs but IgG deposits were observed in a case. Of these 4 cases were selected and stained with anti-IgM, anti-C3 and anti-NE Abs. However IgM and C3 deposits were only observed in one patient who developed myocardial infarction at the age of 39 and was triple positive for APS, anti-SS-A and anti-RNP Abs (Figure 1b). There were also no NE deposits in any of the cases. Even if complement and anti-DNA Ab levels in the serum are normal, attention should be paid to heart disease complications during the long-term observation of SLE patients. In particular, attention should be paid to various autoantibody-positive cases such as APS, anti-SS-A Ab and anti-RNP Ab. The anti-NE Ab was not stained in this study because the tissue was different from the lesion site and because it occurred during the chronic course.

Conclusion

In SLE patients who developed cardiovascular lesions and required surgery, immunological abnormalities may occur in the myocardial tissue even if serum complement and anti-DNA Ab levels are stable.

References

[1]Stephane Zuily et al. Valvular Curr Rheumatol Rep (2013) 15:320.

[2]Zawadowski GM et al. Lupus. 2012;21(13):1378-84.

[3]Daniel Appelgren et al. Autoimmunity 2018,vol51,No.6,310-318.

Disclosure of Interests

None declared

Relations between anterior disc displacement and maxillomandibular morphology in skeletal anterior open bite with changes to the mandibular condyle

In this study we investigated the relation between anterior disc displacement (ADD) and maxillomandibular morphology in skeletal anterior open bite with changes to the mandibular condyle. Thirty female patients (60 joints) with both conditions were evaluated. Magnetic resonance imaging of the temporomandibular joint (TMJ) was used to diagnose both ADD and changes to the mandibular condyle (erosion, osteophyte, and deformity). The relations among ADD, changes to the mandibular condyle, and maxillomandibular morphology were examined statistically. Changes to the mandibular condyle had a higher score than sym anterior open bite, the deviated side in asymmetric anterior open bite, and the non-deviated side. The score for disc displacement on the non-deviated side was lower than both the sym side and the deviated side. Unilateral changes to the mandibular condyle and unilateral disc displacement were not apparent in sym anterior open bite, but a unilateral non-displaced disc was seen only on the asymmetric side. Mandibular condylar changes were significantly more common on the deviated, than on the non-deviated, side. The SNB angle was significantly smaller, and the ANB, GZN, and SN-mandibular plane angles were significantly larger in sym anterior open bite. Overjet, ANB angle, GZN angle, and SN-MP angle were significantly larger, and the SNB angle was significantly smaller, in the presence of ADD without reduction and mandibular condylar deformity. We conclude that the prevalence of ADD without reduction and changes to the mandibular condyle were related to mandibular asymmetry and mandibular morphology in anterior open bite. This retrospective study suggests that ADD without reduction and mandibular condylar bone changes may be related to the progression of skeletal class II open bite and mandibular asymmetry in cases of skeletal open bite.

FRI0179 A STUDY ON THE ACHIEVEMENT OF LUPUS LOW DISEASE ACTIVITY STATE AND QUALITY OF LIFE IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS: FROM THE JUNTENDO UNIVERSITY SLE PROSPECTIVE REGISTRY STUDY

Background:

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease of unknown etiology that affects mostly young women. Multiorgan complications and prolonged treatment significantly cause physical and mental stress in patients. Improving patients’ quality of life (QOL) in SLE treatment is essential. We examined the treatment effects on disease activity and QOL of SLE patients.

Objectives:

In recent years, lupus low disease activity state (LLDAS) has been proposed as a treatment target for SLE. Patients who achieve LLDAS have a low recurrence rate for lupus and a low risk of serious complications (1). The aim of this study is to investigate whether achieving LLDAS reduces not only recurrence rate and complications of SLE but also improves patients’ QOL.

Methods:

A total of 104 SLE patients were enrolled in our prospective SLE registry study (Juntendo, Multi-center, Prospective cohort for investigation of clinical course and outcome in SLE: JUMP) conducted at our institution. SLE was diagnosed using the American College of Rheumatology (ACR) 1982 criteria (revised in 1997). QOL was evaluated using the standard version of the 36-item short form health survey version 2 (SF36v2). Participants were divided into the LLDAS achievement and non-achievement groups, and the characteristics of each group including results of SF36v2 were examined.

Results:

This study included 104 SLE patients, 94 female and 10 male, and the average age and disease duration were 46.4±13.8 and 14.5±11.3 years, respectively. The average corticosteroid dose was 8.0±17.4 mg/day in terms of prednisolone, and anti-dsDNA antibody titer was 16.8±38.5 IU/ml. Of the 104 patients, 57 achieved LLDAS. The subscale’s standard scoring using SF36v2 for role physical (RP) was 78.9±24.0 and 64.6±27.6 (P<0.01), general health (GH) was 50.0±17.0 and 42.0±19.3 (P<0.05), vitality (VT) was 55.8±15.8 and 38.0±24.1 (P<0.01), social functioning (SF) was 82.0±20.7 and 66.5±26.3 (P<0.01), role emotional (RE) was 89.0±16.1 and 73.4±28.1 (P<0.01), and mental health (MH) was 72.4±15.9 and 58.3±21.8 (P<0.01) in the LLDAS achievement and non-achievement groups, respectively. Furthermore, scoring based on the national standard value in the LLDAS achievement group showed that two categories were >50. However, in the LLDAS non-achievement group, all categories were <50. In particular, RP, GH, VT, SF, RE, and MH of the LLDAS achievement group had significantly higher scores than the LLDAS non-achievement group (RP and GH: p<0.05 and VT, SF, RE and MH: p<0.01).

Conclusion:

Results of examining the association between LLDAS and QOL using SF36v2 in SLE patients showed that patients who achieved LLDAS had significantly better standard statistical scores in many subscale categories. Thus, LLDAS achievement as a treatment target for SLE patients greatly contributes to improving patients’ QOL.

References:

[1]Franklyn K, et al. Definition and initial validation of a Lupus Low Disease Activity State (LLDAS).Ann Rheum Dis. 2016 Sep;75(9):1615-21.

Disclosure of Interests:

None declared

Evaluation of non-Gaussian model-based diffusion-weighted imaging in oral squamous cell carcinoma: comparison with tumour functional information derived from positron-emission tomography

AIM

To evaluate and compare diffusion-weighted imaging (DWI) parameters derived from a non-Gaussian fitting model and positron-emission tomography (PET) parameters derived from ¹⁸F-fluoromisonidazole-PET (FMISO-PET) in patients with oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

Primary sites were evaluated prospectively in 18 patients. DWI was performed using six b-values (0-2,500). Diffusion-related parameters of kurtosis value (K), the kurtosis-corrected diffusion coefficient (D_K), diffusion heterogeneity (α), distributed diffusion coefficient (DDC), the slow diffusion coefficient (D_slow), and the apparent diffusion coefficient (ADC) were calculated from four diffusion-fitting models. Maximal standardised uptake values (SUV_max), mean standardised uptake values (SUV_mean), and the tumour-to-muscle ration (TMR) of the SUV value were calculated for FMISO-PET. Spearman's correlation coefficient was used to evaluate the correlation between each non-Gaussian diffusion model parameters and PET parameter.

RESULTS

There was moderate correlation between FMISO-PET SUV_max and D_slow (ρ=-0.45, p=0.06). In addition, there was good correlation between TMR_max and five non-Gaussian diffusion model parameters (K: ρ=0.65, p=0.004, D_K: ρ=-0.72, p=0.0008, DDC: ρ=-0.75, p=0.0003, ADC: ρ=-0.74, p=0.0005, and D_slow: ρ= -0.65, p=0.003), and between TMR_mean and five non-Gaussian model parameters (K: ρ=0.64, p=0.005, D_K: ρ=-0.61, p=0.007, DDC: ρ=-0.63, p=0.005, ADC: ρ=-0.61, p=0.007, and D_slow: ρ=-0.56, p=0.015).

CONCLUSION

Non-Gaussian diffusion model parameters can be related to tumour hypoxia.

[Modified NEWS as a Safe and Inventive Approach for Gastrointestinal Stromal Tumor near the Esophagogastric Junction]

Laparoscopy and endoscopy cooperative surgery(LECS)is an excellent surgical procedure that utilizes the advantages of both methods. Furthermore, non-exposed endoscopic wall-inversion surgery(NEWS)is a more promising procedure that enables avoidance of tumor exposure of and dissemination to the abdominal cavity. However, NEWS has the potential risk of postoperative ulceration, leading to delayed perforation because of mucosal defect. We invented a modified NEWS, which was a safe procedure, by including the all-layer suture to close the mucosal defect. We present a case of gastrointestinal stromal tumor(GIST)near the esophagogastric junction, which was treated with modified NEWS.

Incidence of anterior disc displacement without reduction of the temporomandibular joint in patients with dentofacial deformity

The aim of this study was to investigate the incidence of anterior disc displacement without reduction (ADDwoR) of the temporomandibular joint (TMJ) in patients with dentofacial deformity. Eighty-eight female patients (176 joints) with skeletal class III malocclusion and 33 female patients (66 joints) with skeletal class II malocclusion, with or without anterior open bite and asymmetry, were evaluated. Magnetic resonance imaging (MRI) of the TMJ was used to diagnose ADDwoR. A statistical analysis was performed to examine the relationship between ADDwoR and skeletal structure. ADDwoR was present in 37 of the 66 joints (56.1%) in class II compared to 34 of the 176 joints (19.3%) in class III (P<0.05). In class III, ADDwoR was significantly more common in joints with mandibular asymmetry (24/74; 32.4%) than in joints with open bite (9/62; 14.5%) and joints with open bite and without mandibular asymmetry (1/38; 2.6%). In class II, ADDwoR was significantly less common in joints with mandibular asymmetry and without open bite (1/8; 12.5%). ADDwoR was only observed on the deviated side in both class III and class II with mandibular asymmetry. The prevalence of ADDwoR differed according to the dentofacial morphology.

Ectopic gastrointestinal variceal bleeding with portal hypertension

Massive gastrointestinal bleeding from gastrointestinal varices is one of the most serious complications in patients with portal hypertension. However, if no bleeding point can be detected by endoscopy in the predilection sites of gastrointestinal varices, such as the esophagus and stomach, ectopic gastrointestinal variceal bleeding should be considered as a differential diagnosis. Herein, we report a case of ectopic ileal variceal bleeding in a 57-year-old woman, which was successfully diagnosed by multi-detector row CT (MDCT) and angiography and treated by segmental ileum resection. To date, there have been no consensus for the treatment of ectopic ileal variceal bleeding. This review was designed to clarify the clinical characteristics of patients with ectopic ileal variceal and discuss possible treatment strategies. From the PubMed database and our own database, we reviewed 21 consecutive cases of ileal variceal bleeding diagnosed from 1982 to 2017. MDCT and angiography is useful for the rapid examination and surgical resection of an affected lesion and is a safe and effective treatment strategy to avoid further bleeding.

Arsenic trioxide induces down-regulation of gp46 via protein oxidation: proteomics analysis of oxidative modified proteins in As2O3-treated HTLV-1-infected cells

Adult T-cell leukemia (ATL) is a severe chemotherapy-resistant malignancy associated with prolonged infection by the human T cell-lymphotropic virus 1 (HTLV-1) retrovirus. Epidemiology studies strongly indicate that an increase in HTLV-1 virus load is an important factor during the onset of ATL. Therefore, inhibition of the growth/transmission of HTLV-1 infected cells is a promising strategy in preventing the disease. In our previous study, we revealed that arsenic trioxide (As2O3), a drug used to treat acute promyelocytic leukemia (APL), exerts an inhibitory effect on syncytium formation between HTLV-1 infected cells and HeLa cells via suppression of HTLV-1 envelope protein gp46 expression at low concentrations. In this study, we analyze the mechanism of action of As2O3 using a proteomics approach. Our results suggest that down-regulation of gp46 might be related to As2O3-induced oxidation of the 71-kDa heat shock cognate protein (HSC70) and the 78-kDa glucose-regulated protein (BiP/GRP78). We postulate that AS2O3 exerts an inhibitory effect on HTLV-1 virus transmission via down-regulation of gp46-production, which might be caused by oxidative modification of various proteins such as chaperones.

Creation of an improved mutant TNF with TNFR1-selectivity and antagonistic activity by phage display technology

Tumor necrosis factor-alpha (TNF), which binds two types of TNF receptors (TNFR1 and TNFR2), regulates the onset and exacerbation of autoimmune diseases such as rheumatoid arthritis and Crohn's disease. In particular, TNFR1-mediated signals are predominantly related to the induction of inflammatory responses. We have previously generated a TNFR1-selective antagonistic TNF-mutant (mutTNF) and shown that mutTNF efficiently inhibits TNFR1-mediated bioactivity in vitro and attenuates inflammatory conditions in vivo. In this study, we aimed to improve the TNFR1-selectivity of mutTNF This was achieved by constructing a phage library displaying mutTNF-based variants, in which the amino acid residues at the predicted receptor binding sites were substituted to other amino acids. From this mutant TNF library, 20 candidate TNFR1-selective antagonists were isolated. Like mutTNF, all 20 candidates were found to have an inhibitory effect on TNFR1-mediated bioactivity. However, one of the mutants, N7, displayed significantly more than 40-fold greater TNFR1-selectivty than mutTNF. Therefore, N7 could be a promising anti-autoimmune agent that does not interfere with TNFR2-mediated signaling pathways.

Static bone cavity in the condylar neck and mandibular notch of the mandible

This study presents the radiographic findings of two cases of static bone cavity in the inferior aspect of the condylar neck and mandibular notch of the mandible. On plain CT, a soft tissue mass was observed in each cavity. The submandibular gland and the other glands were not found in each cavity. On contrast-enhanced CT, the soft tissue in the cavity in the inferior aspect of the condylar neck had marked linear enhancement and dilated vasculature structure was observed in the cavity. On the contrast-enhanced MRI, the soft tissue in the cavity of the mandibular notch had marked enhancement and flow void was detected in the cavity. In the inferior aspect of the condylar neck, the cavity size had enlarged radiographically over a period of three years. Vascular lesions were found in the cavity located in the inferior aspect of the condylar neck and mandibular notch of the mandible by both CT and MRI. The vascular lesion might explain the enlargement of the static bone cavity.

Vacuum phenomenon in non-open fracture of the mandibular condyle: report of three cases

Gas in the joint space was observed in three patients with condylar fracture who were referred for CT examinations of the mandible. CT showed that the condylar fractures were non-open fractures. The gas was only observed in the intrajoint capsule of the temporomandibular joint (TMJ). Follow-up CT, 4 days after the initial CT, showed that the gas in the joint space was absorbed in one of three cases. In the non-open condylar fractures, the gas collection in the TMJ was considered to be a vacuum phenomenon due to the intact joint capsule of the TMJ on CT.

CT and MRI findings of intraosseous schwannoma of the mandible: a case report

We report the radiographical findings of a rare case of intraosseous schwannoma of the mandible. The tumour that presented as a unilocular, well-defined, radiolucent lesion on plain radiography was located in the molar region. On CT, the tumour was a well-demarcated mass with no periosteal reaction and no destruction of the bone cortex. Destructive changes in the cortical wall of the mandibular canal by the tumour were observed on CT, but no evidence of dilatation and shift in the inferior mandibular canal was seen. MR imaging revealed that the mandibular canal was encased by the tumour as a solid mass without cystic parts. The signal intensity of the tumour was non-specific on MRI. Characteristics of intraosseous schwannoma in the mandible are the encasement of the canal by a well-demarcated tumour without periosteal reaction and the destruction of mandibular bone cortex. The destructive change of the inferior mandibular canal can be observed on CT and MRI. However, a biopsy is necessary to make the final diagnosis because of the non-specificity of the findings.

Static bone cavity of the mandible: Computed tomography findings with histopathologic correlation

PURPOSE

To review computed tomography (CT) findings of histopathologically examined static bone cavities in order to determine whether an additional pathogenesis may play a role in this disease.

MATERIAL AND METHODS

Four patients with histopathologically examined static bone cavities were included in this retrospective study. Location, appearance of bone remodeling, tissue characteristics, and contrast enhancement of the cavity were assessed on CT images. CT findings were then compared with the histopathological findings.

RESULTS

Static bone cavity was found in the lingual molar region in three patients and in the lingual cuspid region of the mandible in one patient. Both fatty and soft tissues were present in the cavities of all four patients. Attenuation of the soft tissue in the cavities was found to be different from that of the submandibular gland. The soft tissue showed enhancement with contrast-enhanced CT in three patients. For all patients, the histopathologic content of the static bone cavity included fat, soft tissue, and abnormal vasculature. The thickened vein wall in the abnormal vasculature was observed. Aberrant tissue of the submandibular gland was not found in any of the static bone cavities.

CONCLUSION

Contrast enhancement of the soft tissue on the contrast-enhanced CT images suggests the presence of vasculature in the cavities. Histopathological examination confirmed the presence of fatty tissue and dilated abnormal vessels, and the absence of salivary gland tissue in the cavities. These findings show that vascular structures are prominent in tissues found in static bone cavities.

The influence of hot pack therapy on the blood flow in masseter muscles

The purpose of this study was to clarify whether hot pack therapy can change the blood flow of human masseter muscles. Thirty-two healthy subjects with no history of muscle pain in the masticatory system participated and were divided into two groups. One group underwent proper hot pack therapy (hot pack group) and the other underwent sham hot pack therapy (control group). Continuous and non-invasive measurements of haemoglobin volumes and oxygen saturation levels (StO2) were determined with a near-infrared spectroscope. The blood flow parameters were total haemoglobin volume (THb), oxygenated haemoglobin volume (OXHb), deoxygenated haemoglobin volume (deOXHb) and oxygen saturation level (StO2). In hot pack group, results showed that the THb, OXHb and StO2 after the hot pack application were significantly larger than those before the hot pack. In control group, the THb, OXHb, deOXHb, StO2 and heart rates showed no significant differences between the values before and after the sham hot pack application. The THb, OXHb and StO2 after the hot pack application in hot pack group were significantly larger than those in control group, while the deOXHb after the hot pack was significantly smaller than that in control group. The heart rates showed no significant differences between the groups. The results suggest that hot pack therapy can increase regional blood flow of human masseter muscles and creates an advantageous condition for aerobic energy metabolism in the muscles.

Evaluation of static bone cavities with CT and MRI

OBJECTIVES

To determine by CT and MRI the contents of static bone cavities (SBCs), which are thought to be formed by aberration of the submandibular gland.

METHODS

Non-contrast-enhanced and contrast-enhanced CT was performed on 12 subjects (10 male and 2 female; age 18-64 years; mean age 57 years) in whom SBCs had been discovered incidentally on panoramic radiographs during routine dental treatment. MRI was also performed on 3 of the 12 subjects.

RESULTS

No submandibular gland tissue was seen in the SBCs in any of the cases. However, fatty tissue of low attenuation was found in the SBCs in all cases on CT images. Blood vessels were seen in the SBCs in 10 cases, and enhanced soft tissue in contact with the bone cavity wall was seen in the SBCs in 2 cases. Blood vessels in the SBCs were observed on MR images in all three cases. Dilatation of the cavity blood vessels was seen in all 10 cases. Slight tortuosity of the blood vessels was seen in 4 of the 10 cases.

CONCLUSIONS

Examination of contrast-enhanced CT images and MR images revealed that the contents of SBCs were not aberrations of the submandibular gland, as has generally been thought, but fatty tissue, blood vessels and soft tissue.

Electromyographic activity of the jaw-closing muscles during jaw opening--comparison of cases of masseter muscle contracture and TMJ closed lock

Contracture of jaw-closing muscles is one of the causes of limitations of jaw opening. In contracture patients who have no history of trauma or infection, it is not easy to distinguish contracture from temporomandibular joint (TMJ) closed lock (TCL). The purpose of this study was to clarify whether there is any difference between electromyographic (EMG) activities of jaw muscles during jaw opening in patients with TCL and patients with masseter muscle contracture (MMC). The MMC-patient group consisted of one male and 11 females with no history of trauma or infection. The TCL-patient group consisted of one male and 11 females. Ten of the MMC patients showed certain types of EMG activities in masseter muscles (and eight in temporal muscles) during jaw opening. However, particular EMG activities were not observed in most of the TCL patients. The integral values in masseter muscles and in temporal muscles at the maximum opening position were significantly higher in the MMC-patient group than those in the TCL-patient group. These findings demonstrate that the EMG pattern of MMC patients without a history of trauma or infection is different from that of TCL patients. Therefore, EMG analysis of jaw-closing muscles during jaw opening is expected to be useful for differential diagnosis between MMC and TCL.

Comparison of phosphocreatine concentration in the human masseter and medial pterygoid muscles by 31P-CSI

The aim of this study is to compare phosphocreatine (PCr) concentrations of human masseter and medial pterygoid muscles by a recently developed localized magnetic resonance spectroscopy (MRS) method, chemical shift imaging (CSI). The characteristic spectra of phosphorous metabolites including PCr and beta-ATP from the superficial part of the masseter (SM) and the deep part of the masseter (DM) and the medial pterygoid muscles (MPt) from 11 volunteers, 20-27-year-old were obtained. The study clearly demonstrated higher PCr/beta-ATP in the SM and MPt than in the DM both in mean values (P < 0.01) and in individual subjects. The results indicate that SM and MPt are power producers. There were no significant differences in the mean values of the PCr/beta-ATP ratios in SM and MPt, however, the PCr/beta-ATP ratios varied individually and the subjects could be divided into three distinct groups: values of MPt higher than SM (group A, 4 subjects); values of MPt almost equal to SM (group B, 3 subjects); and values of MPt lower than SM (group C, 4 subjects). There appears to be a close relationship between the PCr content as determined in the groups here and occlusal guidance.

Analyses of muscular activity, energy metabolism, and muscle fiber type composition in a patient with bilateral masseteric hypertrophy

Hyperwork of the masseter muscles due to habitual parafunction is thought to induce masseteric hypertrophy (so called work hypertrophy). However, the causes underlying this disease are not yet fully understood. Recently, we had a patient with bilateral masseteric hypertrophy, and we performed a partial excision of the masseter muscles. In this patient's case, we examined muscular activity, energy metabolism, and fiber type composition of the masseter muscles using electromyograms (EMG), 31P-magnetic resonance spectroscopy (MRS), and enzyme-histochemistry. The EMG showed no hyperactivity, and the 31P-MRS showed normal energy spectral patterns and PCr contents of the masseter muscles. The fiber type composition, however, in the muscles in this case was very different from that in muscles with "work hypertrophy" and also that in normal masseter muscles: 1. Loss of type IIB fibers; 2. Increases in type IIA and in type IM & IIC fibers; and 3. Decrease in type I fibers. The findings suggest that this is not a case of work hypertrophy but a case of compensatory hypertrophy possibly due to a lack of high-tetanus-tension type IIB fibers.

A study of quality assessment in clinical microbiology performance of independent laboratories in Tokyo: 18-year participation in the Tokyo Metropolitan Government External Quality Assessment Program

We evaluated the performance of independent microbiology laboratories in Tokyo over an 18-year period of participation in the external quality assessment (EQA) program, and we estimated the impact of the EQA program. The study design was a longitudinal retrospective analysis of performance, including isolation, identification, and antimicrobial susceptibility testing of bacteria from simulated patients' samples, in "open" surveys compared with "blind" surveys. Independent microbiology laboratories, licensed by the Tokyo Metropolitan Government, have been subject to mandatory evaluation by the EQA program since 1982. Survey reports, correspondence, annual guidance meetings, and inspections are used as quality improvement strategies. The performance for identification in "blind" surveys was significantly worse than that in "open" surveys (P < 0.001). Poorly performing laboratories had common features, including inadequate supervision by physicians and lack of familiarity with the impact of variations on the use of the standards. However, there were improvements in the performance of identification of some pathogens. The performance of susceptibility testing has not yet reached the relatively high level seen for identification. Some of the smaller laboratories have been gradually acquired by commercial chains operating outside Tokyo. The EQA program has established a role both in regard to laboratory improvement and as an educational tool. However, the program lags behind these of other developed countries in regard to the practical sciences. The main problems in regard to laboratory improvements are a shortage of human resources in clinical microbiology, lack of standardization of laboratory methods, and the pressures of financial constraints in the Japanese medical insurance system.

Nicotine attenuates stress-induced changes in plasma amino acid concentrations and locomotor activity in rats

It is known that stressor stimuli (both systemic and processive) and nicotine activate central nervous system. Surprisingly, numerous studies have demonstrated an increase in nicotine self-administration among smokers when exposed to stress in order to reduce the stress-related tension. Therefore, in the present study, we decided to investigate the influence of nicotine on both behavioral (i.e., on locomotor activity) and metabolic (i.e., on the level of amino acids in the plasma) changes following water immersion restraint stress in rats. As expected, the stress produced evident decline in locomotor activity of the rats (p < 0.001) and in the levels of all plasma amino acids studied (p < 0.05). Nicotine alone also significantly reduced locomotor activity (p < 0.05) and the levels of some plasma amino acids. However, when administered to rats subjected to water immersion and restraint, nicotine attenuated both stress-induced decrease in locomotor activity (p < 0.05) and in some plasma amino acids. Thus, this study demonstrated that the mode of action of nicotine is strongly dependent on the level of initial brain activity, which provide new evidence for arousal-modulation model of nicotine action.

Regional differences of metabolism in human masseter muscle by two-dimensional 31P-chemical shift imaging

Many reports have demonstrated significant region-dependent differences in the fiber-type composition of the human masseter muscle. Therefore, it is considered that there is intramuscular heterogeneity of metabolic activity in the muscle. The present study was carried out, with two-dimensional Chemical Shift Imaging, to detect differences between the deep and superficial parts of the human masseter muscle at rest. Masseter muscle from 11 volunteers, from 20 to 27 years old, was examined, and characteristic spectra of the inorganic phosphate (Pi), phosphocreatine (PCr), and alpha-, beta-, and gamma-adenosine triphosphate (ATP) from each part of the muscles were obtained. In this study, the deep and superficial parts of the masseter muscle were distinguished by the existence of aponeurosis. The Pi/PCr, PCr/beta-ATP, and Pi/beta-ATP ratios as well as the pH in the deep and superficial parts were calculated from the peak spectra. Compared with the deep part, the Pi/PCr of the superficial part was lower (p < 0.05) and the PCr/beta-ATP was higher (p < 0.01). The Pi/beta-ATP and pH showed no significant differences between the two parts. The results indicate that the superficial part of the masseter muscle contains more PCr than the deep part, and this may be related to functional differences between these two parts. In future examinations of the metabolic activity of the human masseter muscle, the deep and superficial parts must be measured separately.

MRI of the brain in the Kearns-Sayre syndrome: report of four cases and a review

We report brain MRI findings in four patients with typical Kearns-Sayre syndrome (KSS) and correlate them with clinical manifestations. MRI was interpreted as normal in two patients; cerebral and cerebellar atrophy was seen in the other two. On T2-weighted spin-echo images, two patients had high-signal lesions bilaterally in subcortical white matter, thalamus and brain stem. In one patient, the white matter lesion extended into the deep cerebral white matter and the cerebellum was also affected. The other also had bilateral high-signal lesions in the globus pallidus. There was little correlation between neurological deficits and MRI findings. A review of the literature revealed that 10 of the 13 patients with typical KSS previously studied had bilateral subcortical white-matter lesions on T2-weighted images; at least 7 also had high-signal lesions in the brain stem, globus pallidus, thalamus or cerebellum. Although MRI may be normal or show atrophy, the characteristic finding in KSS is a combination of the high-signal foci in subcortical cerebral white matter and in the brain stem, globus pallidus or thalamus.

Comparison of magnetic resonance imaging and gross findings regarding masseter muscle aponeuroses in cadavers

OBJECTIVES

The main objective of this study was to compare the actual distribution and thickness of aponeuroses in cadavers with the distribution and thickness as determined by means of magnetic resonance imaging for the sake of evaluating magnetic resonance imaging as a diagnostic modality for assessing masseter muscle aponeuroses.

STUDY DESIGN

The aponeuroses of 26 masseter muscles from 13 intact cadavers were examined by magnetic resonance imaging.

RESULTS

The ratio of concordance between gross findings and magnetic resonance imaging findings was 99.0%, although depiction of thin parts of the aponeuroses on magnetic resonance imaging was poor.

CONCLUSIONS

Magnetic resonance imaging was useful as a diagnostic modality in the assessment of masseter muscle aponeuroses. Aponeuroses were distributed throughout almost the entire masseter muscle, although almost no aponeuroses were seen below the lower half of the anterior margin. This was thought to be a characteristic finding of masseter aponeuroses.

[A case of ureteral malacoplakia in a hemodialysis patient]

A case of ureteral malacoplakia in a hemodialysis patient is reported. A 64-year-old woman suffering from macrohematuria, was diagnosed as having a right ureteral tumor by means of computerized tomography and antegrade pyelography. Right nephroureterectomy with bladder cuff resection was performed. Pathological examination indicated malacoplakia; multiple Michaelis-Gutmann bodies were found. The patient did well postoperatively and was discharged without further complications. This case appears to be the twenty-first report of ureteral malacoplakia in the world.

Contingent negative variations associated with jaw opening in humans

We examined the relationship between contingent negative variation (CNV) amplitude and digastric muscle activity in jaw-opening motor task. Subjects were instructed to open their jaws in response to a sound stimulus following a visual warning stimulus. Electroencephalograms were averaged by using the visual stimulus pulse as a trigger. Bilateral CNVs were clearly recorded at several cortical locations, with a tendency for larger amplitudes at temporal placements.

Intrahepatic portosystemic venous shunt: diagnosis by color Doppler imaging

Intrahepatic portosystemic venous shunt is a rare clinical entity; only 33 such cases have been reported. It may be congenital, or secondary to portal hypertension. Five patients with this disorder are presented, each of whom was diagnosed by color Doppler imaging, including waveform spectral analysis. One patient with clinical evidence of cirrhosis and portal hypertension had episodes of hepatic encephalopathy and elevated blood levels of ammonia. This patient had a large tubular shunt between the posterior branch of the portal vein and the inferior vena cava. Shunts of this type are considered to be collateral pathways which develop in the hepatic parenchyma as a result of portal hypertension. The other four patients had no evidence of liver disease, and all four evidenced an aneurysmal portohepatic venous shunt within the liver parenchyma. Shunts of this type are considered congenital. The diagnosis of intrahepatic portosystemic venous shunts was established by color Doppler imaging, which demonstrated a direct communication of color flow signals between the portal vein and hepatic vein, in addition to the characterization of the Doppler spectrum at each sampling point from a continuous waveform signal (portal vein) to a turbulent signal (aneurysmal cavity), and finally, to a biphasic waveform signal (hepatic vein). As demonstrated by the five patients, color Doppler imaging is useful in the diagnosis of an intrahepatic portosystemic hepatic venous shunt, and the measurement of shunt ratio may be useful in the follow-up and determining the therapeutic option.

[Case report of Farmer's lung disease in siblings in Kagoshima Prefecture]

Two cases of farmer's lung disease in siblings are reported. A 54-year-old male farmer, who had been engaged in stock work for 20 years, presented to our clinic for the second episode of fever, productive cough and shortness of breath. Chest roentgenogram revealed diffuse micronodular pattern, and mild hypoxemia was recognized on arterial blood gas analysis. Cytology obtained from BALF showed lymphocytosis, with especially increased OKT3, OKT4 positive cells and OKT4/8 ratio. The diagnosis was confirmed by highly positive reaction of precipitins to Thermoactinomyces vulgaris and granulomatous interstitial pneumonitis on histopathological examination. The second case was a 51-year-old female patient, the sister of the first case, who also worked as a stock farmer of another farm for 20 years. She presented with an episode of similar symptoms to the first case, one and a half years after the onset of her brother's symptoms. The findings of roentgenogram, BALF analysis, precipitins to T. Vulgaris and pathology were similar to those of the first case. The finding of high OKT4/8 ratio on BALF analysis in both cases is characteristic of formers lung disease, in contrast to the summer-type hypersensitivity pneumonitis which usually shows low OKT4/8 ratio in BALF. To our knowledge, this is the first report of farmer's lung disease in an area other than the northern part of Japan. Thus we conclude that farmer's lung disease may occur in Japan under any environmental conditions, and that some genetic factor may take part in the onset of this disease.

Neural activities during replacement of blood with fluorocarbon emulsion

Exchange transfusion of the blood with fluorocarbon (FC) emulsion was conducted in the cat ventilated spontaneously with high oxygen tension gas, and responses of various neural activities to this replacement were studied. Animals survived in good physiological condition, at hematocrit values of less than 5%, more than 3 hours after the end of the FC transfusion. Electroencephalographic activity and afferent impulses of the carotid sinus nerve increased and sympathetic renal nerve activities decreased compared with the control activities before the replacement, indicating no impairment in the reflexogenic control of the respiratory and circulatory systems. Moreover, the amplitudes of the sensory evoked cortical potentials increased with lower hematocrit values during FC treatment. However, early components of auditory brain stem responses did not increase as markedly compared with the cortical responses. We concluded that the general condition of the animals and the neural responses examined were well preserved after FC emulsion exchange transfusion.

Changes in dietary fiber intake among Japanese in the 20th century: a relationship to the prevalence of diverticular disease

In view of the fact that Japanese dietary patterns have been undergoing rapid "Westernization," in part characterized by decrease in fiber, we assessed dietary and crude fiber content in the Japanese diet using food consumption tables for the period from 1911 to 1980, and studied the trend in the reported prevalence of diverticular disease of the colon. Fiber content declined in diphasic pattern: the first decline, which probably had started in the late 19th century, progressed until the Second World War. Although records during the war period were unavailable, the high fiber content of the Japanese diet in the period immediately after the war reflects the tendency to supplement rice with more fiber-rich cereals, and to increase the amount of rice through reduced polishing during the war time. The second decline in fiber content in the Japanese diet, which started in the 1950s and progressed throughout the period of "high economic growth," was mainly due to the decrease in cereal consumption. The changes in crude fiber content in the Japanese diet after the Second World War resemble the pattern of rapid decline noted in the United States during the 1930s to the 1950s. The prevalence of diverticular disease in both countries also shows sudden steep upward turns during the period between 1930 and 1950 in the United States and the late 1970s in Japan, suggesting the presence of threshold level(s) of fiber intake for the effective prevention of diverticular disease. The prevalence of diverticular disease is still relatively low in Japan. However, if the current dietary trend continues, it may rise to a level currently found in the "Western" countries in the coming few decades.

Chronological relationship between neurological signs and electrophysiological changes in rats with methylmercury poisoning - special reference to selenium protection

In order to see chronological relationship between electrophysiological changes and "early" neurological sign (tail rotation) elicited in rats poisoned with methylmercury, we made serial measurements of amplitude of compound action potential and sensory nerve conduction velocity of the tail nerve in rats with five dose schedules [methylmercury vs selenium, (1)20 ppm:0.1 ppm, (2)20: 0.3, (3)20: 0.6, (4)10: 0.1, (5)10: 0.6]. We observed the following sequence in the onset of neuro-electro-physiolo-somatic signs: fall in compound action potential greater than decrease in sensory nerve conduction velocity greater than tail rotation greater than weight loss. Protective potency of dietary selenium against neurotoxicity of methylmercury was observed with regard to both electrophysiological changes and neurological signs.

Acute lead poisoning of the pigeon induced by single, intraperitoneal administration of lead acetate

A single dose of lead acetate (either 30 mg/kg or 150 mg/kg) was intraperitoneally (i.p.) administered to adult feral pigeons, Columba livia var and the effects of calcium disodium ethylenediamine tetraacetate (CaNa2EDTA), (0, 150, 300, 600 mg/kg), administered i.p. twice a week in the ensuing period were observed. Lead acetate caused dose related mortality and decreases in weight, hematocrit and delta-aminolevulinic acid dehydratase activity (ALA-D). Acute toxicity of lead acetate in the pigeon, when given intraperitoneally, appeared approximately equivalent to that in the rat and mouse in terms of LD50. Blood lead (blood Pb) levels observed during the lethal stage were five to ten times less than those reported for chronic oral lead poisoning in the pigeon. Biological implications of elevated levels of blood Pb observed in the feral pigeon in the urban Tokyo area are discussed. CaNa2EDTA induced dose related recovery in ALA-D in 30 mg/kg group, and reduction of blood Pb levels in the group dosed with 150 mg/kg of lead acetate.