[Successful surgical repair of acute DeBakey type I aortic dissection complicated by acute occlusion of the suprarenal abdominal aorta]

We reported a case of acute DeBakey type I aortic dissection presented with occlusion of the suprarenal abdominal aorta, who was successfully treated by simultaneous graft replacement of the ascending aorta and total aortic arch. The patient was a 68-year-old man who complained of chest pain and symptoms of acute arterial occlusion of bilateral lower extremities, and who had consciousness disturbance due to stroke caused by aortic dissection. He underwent simultaneous graft replacement of the ascending aorta and total aortic arch under selective cerebral perfusion during an emergent operation. For reconstruction of the arch vessels, we used three separate grafts that were connected to the aortic prosthesis before use. Although postoperative course was complicated by myonephropathic metabolic syndrome, the patient subsequently recovered and was discharged on foot. Early vascular reconstruction and appropriate management of reperfusion injury are extremely important in the setting of malperfusion phenomena complicating acute aortic dissection.

Differences between 99mTc-DTPA and 99mTc-MAG3 captopril renographies in renovascular hypertension

Captopril renography (CRS) with 99mTc-DTPA and 99mTc-MAG3 was performed on a 21-year-old woman with renovascular hypertension due to right renal artery stenosis caused by fibromuscular dysplasia. In the affected kidney, the renogram pattern was substantially changed with 99mTc-DTPA and 99mTc-MAG3 following the administration of captopril, and the quantitated renal uptake indicating individual renal function was significantly decreased in 99mTc-DTPA and slightly decreased in 99mTc-MAG3. In the contralateral normal kidney, the renogram showed some minor changes with both radioagents, while the quantitated renal uptake was significantly decreased with 99mTc-DTPA and substantially increased with 99mTc-MAG3. The combined use of physiologically different renal agents 99mTc-DTPA and 99mTc-MAG3 is helpful in investigating hemodynamic and functional changes in the stenosed kidney as well as the normal kidney in RVH.

The evaluation of masticatory function with low adhesive colour-developing chewing gum

Many objective methods have been described to evaluate masticatory function. Recently, a new chewing gum system has been reported that utilizes a phloxine-sodium bicarbonate reaction and measures a chromatic coordinate as a functional indicator. A low-adhesive colour-developing chewing gum has been developed by selecting an appropriate gum base. This study examined the applicability of the system and reproducibility of results in subjects with different dental states. Tests were performed on 15 natural dentate subjects and 15 complete denture wearers after determination of germane test conditions through a pilot study. The colour was measured by a*, one of the coordinates in the L*a*b* colour system. All subjects could perform the test. The coefficient of variation ranged from 1.87% to 7.90%, averaging 5.15% in the natural dentate subjects and from 1.5% to 17.9%, averaging 9.75% in the complete denture wearers. The 95% confidence interval of a* was 28.76 +/- 1.76 in the natural dentate subjects and 10.05 +/- 2.58 in the complete denture wearers. The results indicated that this material can be useful for both complete denture wearers and subjects with a natural dentition with adequate reproducibility.

[Dissection of the interventricular septum with aorto-left ventricular communication due to infective endocarditis--report of a rare case]

Dissection of the interventricular septum is an uncommon manifestation, which is rarely associated with infective endocarditis, aneurysm of sinus of Valsalva and thoracic trauma. We report a 34-year-old male case with aorto-left ventricular communication due to infective endocarditis. The patient had chief complaints of dyspnea on exertion and precordial discomfort. Preoperative laboratory data showed normal white blood cell counts, a slightly elevated CRP, and negative blood culture in bacterial examinations. Echocardiogram revealed progressive dissection of the interventricular septum and stenosis of the left ventricular outflow tract. Disturbance of conduction including progressive atrioventricular block and bundle branch block were found in the electrocardiogram. The dissection extended over 2 x 2 x 2.5 cm in diameter, with an entry located at the basis of the right coronary cusp and reentry communicated to the left ventricle. Operative procedures included the aortic valve replacement with prosthetic valve due to severe inflammation, in addition to resection of the dissecting cavity. Pathological examination of the resected tissue accorded with infective endocarditis in active phase, showing necrosis, small cell infiltration and microabscess. However, a bacterial colony was not found in the surgical specimen. Postoperative course was uneventful and the patient was discharged in satisfactory conditions.

[Successful aorto-coronary bypass grafting and concomitant left ventricular myotomy-myectomy in a patient with coronary artery disease associated with hypertrophic obstructive cardiomyopathy]

A 65-year-old man complained chest oppression at rest and dizziness. Echocardiography showed subaortic stenosis with outflow gradient of 100 mmHg, although interventricular septal thickness was only 12 mm and left ventricular posterior wall thickness was 11 mm, and mild mitral regurgitation. Selective coronary angiography demonstrated 90% stenosis in left main truncus, 50% stenosis in first diagonal branch, and hypoplastic right coronary artery. Emergent coronary artery revasculization concomitant with left ventricular myotomy myectomy was performed. Immediately after weaning off the cardiopulmonary pump, IABP was employed for cardiac assistance, because of residual left ventricular outflow pressure gradient, which was provoked by cathecholamine and amyl nitrite. He was discharged in 1 month in NYHA class I. Echocardiography 3 months after operation showed no residual outflow pressure gradient, no systolic anterior motion of mitral anterior leaflet, and mild approximately mitral regurgitation. Careful operative management, including myocardial protection and avoiding perforation of ventricular septum and postoperative medical care are mandatory to this group of patients. This case is the first successful coronary artery bypass grafting and concomitant left ventricular myotomy-myectomy reported in Japan.

Masticatory function of postoperative tumor patients rehabilitated with osseointegrated implants

PURPOSE

This study determined the level of masticatory function that can be achieved with osseointegrated implants in postoperative tumor patients.

PATIENTS AND METHODS

Masticatory function was evaluated in 15 postoperative tumor patients with implants, 22 nontumor patients with implants, and 15 natural dentate controls. The area of occlusal contact was evaluated with a pressure-sensitive, color-developing bite sheet analyzed by computer. Chewing performance was evaluated by a low-adhesive, color-developing, chewing-gum system.

RESULTS

Subjects in the tumor group had load-bearing tooth contacts similar to those of the natural dentate controls and nontumor implant patients. Continuity of the mandible was essential to sustain occlusal load. The presence of the hypoglossal nerve was the main factor in determining restoration of chewing performance.

CONCLUSIONS

Surgical efforts to preserve the mobility of the residual tongue and prosthetic approaches to restore impaired mobility to as great an extent as possible are especially important for better functional rehabilitation of patients who have defects of the hypoglossal nerve.

Regulation of energy metabolism by interleukin-1beta, but not by interleukin-6, is mediated by nitric oxide in primary cultured rat hepatocytes

The effects of inflammatory cytokines (interleukin-1beta, interleukin-6, and tumor necrosis factor-alpha) on energy metabolism were studied in primary cultured rat hepatocytes. Adenine nucleotide (ATP, ADP, and AMP) content, lactate production, the ketone body ratio (acetoacetate/beta-hydroxybutyrate) reflecting the liver mitochondrial redox state (NAD+/NADH), and nitric oxide formation were measured. Insulin increased ATP content in hepatocytes and had a maximal effect after 8-12 h of culture. Both interleukin-1beta and interleukin-6, but not tumor necrosis factor-alpha, significantly inhibited the ATP increase time- and dose-dependently. Interleukin-1beta and interleukin-6 also stimulated lactate production. During the same period, interleukin-1beta but not interleukin-6 decreased the ketone body ratio. Furthermore, interleukin-1beta markedly stimulated nitric oxide formation in hepatocytes, and this increase was blocked by NG-monomethyl-L-arginine (a nitric oxide synthase inhibitor) and by interleukin-1 receptor antagonist. NG-monomethyl-L-arginine reversed inhibition of the ATP increase, decrease in the ketone body ratio, and increase in lactate production, which were induced by interleukin-1beta. Interleukin-1 receptor antagonist completely abolished all of the effects induced by interleukin-1beta. These results demonstrated that interleukin-1beta and interleukin-6 affect the insulin-induced energy metabolism in rat hepatocytes by different mechanisms. Specifically, interleukin-1beta inhibits ATP synthesis by causing the mitochondrial dysfunction, a process which may be mediated by nitric oxide.

Genetic analysis of the Saccharomyces cerevisiae RHO3 gene, encoding a rho-type small GTPase, provides evidence for a role in bud formation

RHO3 encodes a Rho-type small GTPase of the yeast Saccharomyces cerevisiae. We isolated temperature-sensitive alleles and a dominant active allele of RHO3. Ts- rho3 cells lost cell polarity during bud formation and grew more isotropically than wild-type cells at nonpermissive temperatures. In contrast, cells carrying a dominant active mutant RHO3 displayed cold sensitivity, and the cells became elongated and bent, often at the position where actin patches were concentrated. These phenotypes of the rho3 mutants strongly suggest that RHO3 is involved in directing the growing points during bud formation. In addition, we found that SRO6, previously isolated as a multicopy suppressor of rho3, is the same as SEC4. The sec4-2 mutation was synthetic lethal with temperature-sensitive rho3 mutations and suppressed the cold sensitivity caused by a dominant active mutant RHO3. The genetic interactions between RHO3 and SEC4, taken together with the fact that the Rab-type GTPase Sec4p is required to fuse secretory vesicles together with plasma membrane for exocytosis, support a model in which the Rho3p pathway modulates morphogenesis during bud growth via directing organization of the actin cytoskeleton and the position of the secretory machinery for exocytosis.

Maternal allergen stimulation suppressed respiratory allergy in offspring: with special reference to allergy related cells in the tonsil

Pregnant mice and Hartley guinea pigs were immunized with T dependent antigen, heterologous erythrocyte and ovalbumin (OVA), and the active immune responsiveness as well as the allergic symptoms of the offspring were investigated. Guinea pigs were also sensitized to OVA intraperitoneally and subcutaneously with a 100 mg/ml solution of saline containing 5 mg of AI(OH)(3) as an adjuvant. Six weeks after the initial allergen stimulation, systemic and local anaphylaxis as elicited by 1-min aerosol administration of a nebulizer and monitored by macroscopic vision accompanied by a time trial for respiratory and cardiac arrest. Serum antibody levels were tested by passive hemagglutination as well as passive cutaneous anaphylaxis especially for the estimation of IgE levels. Nasal, tonsillar and bronchial tissues were also prepared and fixed, followed by hematoxylin and eosin staining for histological observation. In the offspring of mothers who had been stimulated with optimal amounts of the allergen and had fully developed specific antibodies against the allergen, there was a clear-cut suppression in the development of a specific respiratory allergy over a significant period after delivery. The effect was confirmed by systemic and local anaphylaxis, eosinophil infiltration, ciliary deformation in nasal mucosae and the tonsillar site in the complex interaction of various cell types and mediators eliciting the clinical respiratory symptoms, in particular nasal hypersensitivity. In a different experimental model, the mouse model, these biological findings were not regulated by maternal transferable antibody or antigen fragments from the mother. The induction of suppressor T cell (CD(4+)) in offspring depends on the recognition of the antigens presented in association with the same MHC haplotype as that utilized in the maternal T cell response during pregnancy. These results suggest the presence of suppression mechanisms in the offspring of mothers stimulated during pregnancy. From these results, we discuss the mechanisms for suppression and protective efficacy for respiratory allergy as well as possible side effects in the young of mothers stimulated during pregnancy.

A computerized method for evaluating distribution of occlusal load on implant-supported fixed cantilever prostheses

An investigation was conducted to determine whether Dental Prescale, a material that undergoes a graded color-producing chemical reaction when force is applied, could be used to evaluate occlusal load distribution objectively and quantitatively when combined with computer analysis. Ten patients with an implant-supported fixed cantilever prosthesis and a complete conventional maxillary denture were studied. The results indicated that the system can be used to evaluate occlusal load distribution with sufficient reproducibility. However, in its present form, the system is somewhat cumbersome, and its use must now be considered experimental. Further refinement is necessary to allow easier clinical use.

Congenital stationary nightblindness in a patient with osteopetrosis

Images

Preoperative disseminated intravascular coagulation (DIC) associated with aortic aneurysm--does it need to be corrected before surgery?

Disseminated intravascular coagulation (DIC) is one of the complications accompanying aortic aneurysm. We herein report four patients with aortic aneurysm who had DIC preoperatively. In all four cases, DIC was corrected immediately after surgery; however, in two cases, DIC could not be corrected preoperatively. This prompted us to reconsider the importance of correcting DIC before surgery. Of the four cases reported in this paper, DIC existed even at the time of surgery in two cases, in spite of meticulous treatment with heparin and/or protease inhibitor; however, the DIC could be removed postoperatively even in these two cases. Surgeons should not waste time with intensive DIC treatment preoperatively. If the DIC cannot be corrected within more than 2 weeks of meticulous treatment, surgeons should then perform surgery on the patient. In addition, it is also essential to ensure that the DIC is due to the aneurysm itself and that no other disease processes have been overlooked.

Seronegative myasthenia gravis associated with atonic urinary bladder and accommodative insufficiency

We report a 20-year-old female with generalized myasthenia gravis (MG) who developed atonic urinary bladder and accommodative insufficiency. Although her sera did not contain antibodies to either nicotinic acetylcholine receptor (AChR) or voltage-gated calcium channels, a positive intravenous edrophonium test and a waning phenomenon on electromyographic studies indicated a diagnosis of seronegative MG. Myasthenic symptoms as well as urinary incontinence and impaired near vision disappeared with slight sequelae after corticosteroid therapy and total removal of the hyperplastic thymus. These symptoms recurred during a tapering course of corticosteroids, and improved again with an increased dose. Therefore, in this patient, the neuromuscular transmission of muscarinic type of AChR in the smooth muscles was also affected. This patient provides insight into the mechanisms by which some smooth muscles are involved in MG.

Application of a low-adhesive color-developing chewing gum system to patients with osseointegrated implant-supported prostheses

Few methods have been described that can quantitatively evaluate masticatory function. This study investigated the usefulness of a low-adhesive color-developing chewing gum system for the evaluation of patients with implant-supported prostheses. Fifteen dentate subjects and 22 patients with dental implants participated in this study. The color developed in the gum after chewing reflects masticatory function and is evaluated quantitatively with a color-analyzing system. The results indicate that this system can be used to evaluate occlusal function, and they confirm the importance of stable prostheses for higher masticatory function.

[A clinical study of six cases of toxic shock-like syndrome by group A Streptococcus]

We have encountered six cases with toxic shock-like syndrome (TSLS) by Group A Streptococcus since 1978. Every patient had from the onset flu-like symptoms or high fever and immediately developed some of the following clinical signs: hypotension, acute renal failure, disseminated intravascular coagulation (DIC), and adult respiratory distress syndrome (ARDS). Three of the six patients died with rapid clinical courses and three survived. As for the surviving patients, early administration of antibiotics and anti-DIC therapy were effective. Streptococcus pyogenes were isolated from the blood in five of the patients, ascites from another, and necrotizing tissue in one patient. The serovars of the isolated strains were typed as T1/M1 in three, T8 in one, and T28 in another. The toxin-type of the strains were typed as B in four and B + C in one. Though there have been few reports of TSLS before 1992 in Japan, it is supposed that many TSLS cases may have potentially occurred.

Murine polo like kinase 1 gene is expressed in meiotic testicular germ cells and oocytes

To identify key molecules that regulate germ cell proliferation and differentiation, we have attempted to isolate protein kinase genes preferentially expressed in germ line cells. One such cDNA cloned from murine embryonic germ(EG) cells encodes a nonreceptor type serine/threonine kinase and is predominantly expressed in the testis, ovary, and spleen of adult mouse. The nucleotide sequence of the entire coding regions shows that this clone, designated Plk1(polo like kinase 1), is identical with STPK13 previously cloned from murine erythro-leukemia cells. The protein encoded by Plk1 is closely related to the product of Drosophila polo that plays a role in mitosis and meiosis. To define the role of Plk1 in germ cell development, we have examined its expression in murine gonads by in situ hybridization. Here we show that the Plk1 gene is specifically expressed in spermatocytes of diplotene and diakinesis stage, in secondary spermatocytes, and in round spermatids in testes. It is also expressed in growing oocytes and ovulated eggs. The pattern of expression of the Plk1 gene suggests that the gene product is involved in completion of meiotic division, and like the Drosophila polo protein, is a maternal factor active in embryos at the early cleavage stage.

Melittin cardiotoxicity in cultured mouse cardiac myocytes and its correlation with calcium overload

Venom from the honey bee Apis mellifera induces cardiovascular dysfunction. We studied which constituent(s) of the venom induces cardiotoxicity and how, using cultured cardiac myocytes from mouse fetuses. Among the venom constituents, only melittin caused contractile and morphological effects; other peptides, such as apamin and mastparan; enzymes, such as phospholipase A2; and low-molecular-weight compounds, such as histamine and dopamine, did not. Treatment with 4.5 micrograms/ml melittin, which accounts for about half the dry weight of the venom, induced the same cardiotoxic effects as treatment with 9.0 micrograms/ml whole venom; these effects were a transient increase in the spontaneous beating rate, then a decrease, then cessation of beating, and finally, morphological degeneration. The cardiotoxicity of whole bee venom was completely destroyed by pretreatment of the venom with antimelittin antibody. These results suggest that bee venom cardiotoxicity is attributable to melittin. When spontaneous beating ceased following the addition of melittin or whole venom, an increase in systolic [Ca2+]i, was observed. On further incubation with melittin or bee venom, morphological injury, such as balloon degeneration, occurred concomitant with a further increase in the [Ca2+]i. An extracellular Ca2+ concentration of more than 10(-6) M was necessary for morphological injury. Melittin depolarized the maximum diastolic potentials, inhibited the generation of action potentials, and induced an increase in [Na+]i. Cells were protected against the melittin-induced increase in [Ca2+]i by pretreatment with bepridil, an inhibitor of Na(+)-Ca2+ exchange, but not by Ca2+ channel blockers such as verapamil. These observations suggest that the melittin-induced increase in [Ca2+]i was due to entry of extracellular Ca2+ via the sarcolemmal Na(+)-Ca+ exchange system.

The accumulation and energy load of exogenous lipids in cirrhotic rat liver after partial hepatectomy

BACKGROUND

The suitability of three energy substrates, glucose, medium-chain triglycerides (MCT) and long-chain triglycerides (LCT), was studied in cirrhotic rats after a partial hepatectomy.

METHODS

Rats with thioacetamide-induced cirrhosis underwent a 70% hepatectomy, and were divided into three groups. Each group was then injected with 14C-labeled glucose, 14C-labeled MCT or 14C-labeled LCT, respectively. The subsequent tissue distribution of 14C and the cumulative amount of expired 14CO2 were determined. In a second experiment, the 70%-hepatectomized cirrhotic rats received total parenteral nutrition (TPN). The source of the nonprotein calories was 100% glucose (glucose group), 60% MCT + 40% glucose (MCT group), and 60% LCT + 40% glucose (LCT group). The adenylate energy charge and the glycogen content in the liver remnant were determined.

RESULTS

The tissue distribution of 14C revealed that the fat emulsions accumulated preferentially in the liver. One hour after the partial hepatectomy, the concentration of 14C-labeled MCT in the liver remnants was threefold higher than in sham-operated controls. Similarly, the concentration of 14C-labeled LCT was twofold higher. The adenylate energy charge in the glucose group with TPN recovered to preoperative levels within 1-hour after the partial hepatectomy, whereas the LCT group with TPN showed a 24-hour delay in their recovery. The MCT group with TPN exhibited an intermediate time course.

CONCLUSIONS

It is suggested that the specific accumulation of MCT and especially LCT emulsions in the cirrhotic liver remnant acts as an energy load rather than an energy substrate.

Ultrastructural features of alveolitis in sarcoidosis

Seventy-nine specimens of lung parenchyma from 61 patients with sarcoidosis were examined ultrastructurally with a focus on alveolitis, and they were compared with specimens of hypersensitivity pneumonitis (HP) and the percentage of lymphocytes in bronchoalveolar lavage fluid (BALF). Lymphocytes and monocytes were frequently observed in the capillary lumina, and these cells and macrophages were found in the interstitium of the alveolar walls in the specimens with alveolitis of sarcoidosis and HP. Increases in the percentage of lymphocytes in BALF correlated with the degree of alveolitis. Swelling and bleb formation of the endothelium of alveolar capillaries and changes in the capillary basement membrane were commonly found and were significantly increased in the specimens with alveolitis. The frequency of bleb formation was significantly higher in alveolitis of sarcoidosis than in that of HP. However, the changes in alveolar epithelium were not significant in sarcoidosis. Microvascular changes in alveolitis are not specific for sarcoidosis, but they are observed in other interstitial lung diseases. These alterations may play an important role in the development of pulmonary sarcoidosis.

Spinal cord protection during thoracoabdominal aortic aneurysm repair: results of selective reconstruction of the critical segmental arteries guided by evoked spinal cord potential monitoring

PURPOSE

The purpose of this study is to evaluate the results of spinal cord protection based on selective reconstruction of the segmental arteries.

METHODS

Twenty-one patients who underwent repair of aneurysms (nine descending thoracic and 12 thoracoabdominal: three type I, six type II, and three type III) were analyzed. Ten patients had postdissection aneurysms. Operative techniques consisted of evoked spinal cord potential (ESP-dsc) monitoring and femorofemoral bypass in all cases, segmental resection in 12, and mild systemic hypothermia in eight. Arteries critical for cord blood flow were selectively reconstructed; if ESP-dsc showed change after resection of an aortic segment, arteries originating from this segment were reconstructed.

RESULTS

ESP-dsc change was observed in 12 patients. Arteries found to be critical were at the T8-L1 level in all but three cases. Selective reconstruction was performed in 10 of these 12 patients. ESP-dsc change could be reversed before reconstruction in four cases, three by control of back-bleeding critical arteries. Selective reconstruction resulted in return of ESP-dsc in seven other patients. Spinal cord injury occurred in five patients, two of whom did not undergo selective reconstruction.

CONCLUSION

These results suggest that our current technique allows determination of critical arteries but does not completely prevent injury.

Speech function following maxillectomy reconstructed by rectus abdominis myocutaneous flap

Post-surgical maxillary defects have recently been reconstructed by microvascularized free flaps. However, few reports have evaluated the resulting speech function. This study compared the speech intelligibility of four maxillectomy patients who underwent reconstruction by rectus abdominis myocutaneous flaps (RAMCF) with that of four non-reconstructed patients who were treated with split-skin grafts and prostheses, to explore ways of achieving better speech function. Speech function was assessed by a Japanese language speech intelligibility test. Intelligibility scores ranged from 57.3% to 75.8% (mean, 70.4%) in the non-reconstructed group and from 66.2% to 77.2% (mean, 71.0%) in the reconstructed group. An analysis of articulatory manners and sites revealed that speech disorders resulted mainly from poor oronasal separation in the non-reconstructed group and from incorrect linguopalatal contact in the reconstructed group, especially for linguodentoalveolar and linguovelar sounds. Therefore, for higher speech function in the reconstructed group, dentoalveolar and palatal contours of the maxilla must be restored as closely as possible. This must also be done in patients whose maxillae are reconstructed by other types of microvascularized myocutaneous or cutaneous flaps that have similar postoperative palatal contours.