The evaluation of preoperative embolization of meningioma

SUMMARY

To evaluate the efficacy of preoperative embolization of meningioma, we examined the correlation between the angiographic disappearance of the tumor blush after the embolization and the volume of blood loss and transfusion intraoperatively. Preoperative embolization of meningioma with intravascular neurosurgery was attempted for 42 trials, 41 cases from July 1989 to December 1995. There were no major complications attributed to the embolization procedure. As a subjective assessment in 23 cases the information from the surgeon following the operation was obtained. The angiographic disappearance of the tumor blush and reducing of the bleeding from tumor could be considered to be statiscally significant (p < 0.05). As an objective assessment in 37 cases following operation, the volume of both intraoperative blood loss and blood transfusion was examined. The angiographic disappearance of the tumor blush and reduced intraoperative blood transfusion could be also considered to be statiscally significant (p < 0.05), otherwise reduced intraoperative blood loss failed to reach the significance level. 1n this study the efficacy of preoperative embolization of meningioma has been especially shown to reduce intraoperative blood transfusion significantly, therefore it is very useful to increase the chance of complete tumor removal with more safely and less invasively.

Detection of Unstable Plaques in Patients with Carotid Stenosis using B-Mode Ultrasonography

SUMMARY

Distal embolism is a detrimental complication of stent placement for the carotid artery stenosis. To evaluate usefulness of B-mode ultrasonography (US) for the detection of unstable plaques in patients with carotid artery stenosis, we examined US in 46 arteries of 35 patients with carotid stenosis of > 30%. The echogenicity of 46 carotid plaques was hyperechoic in 20 plaques, hypoechoic in 15, and mixed-echoic in 11. The echogenicity of carotid plaques was correlated with severity of carotid stenosis, ipsilateral stroke or TIA, heart attack, and risk factors of systemic atherosclerosis. Hypoechoic plaques were associated with severe carotid stenosis and ipsilateral ischemic event. Mixed-echoic plaques had a high incidence of past history of heart attack. Hyperechoic plaques were less likely to associate with risk factors of systemic atherosclerosis. We developed a new method of echodensity analysis. Using a computer software, echodensity values of seven plaque components were determined by comparing US findings and pathology of surgical specimens. The echodensity value was defined as a relative value to the arterial lumen. The calcified part of plaques had the highest echodensity of 6.24 +/- 0.86 (mean +/- 2 S.D.); fibrosis or hyarynoid degeneration of 2.05 +/- 0.40, foamy histiocytes of 1.47 +/- 0.05, necrosis of 1.32 +/- 0.16, cholestelin clefts of 1.28 +/- 0.13, intraplaque hemorrhage of 1.02 +/- 0.09, and intraluminal thrombus of 1.27 +/- 0.07. Constructed from the echodensity value, an echo-densitometry color mapping of the carotid plaque illustrated the exact location and extent of plaque component. B-mode US of carotid plaques represents clinical characteristics relating distal embolism and systemic atherosclerosis. A new method of echodensity analysis and echo-densitometry color mapping of the carotid plaque is useful to detect unstable plaques in patients with carotid stenosis.

Association between cadmium concentration in rice and mortality in the Jinzu River basin, Japan

A follow-up survey on 2101 inhabitants (1566 men, 535 women), who participated in a 1967 health survey and had resided in their present rural community since birth was conducted to determine the influence of environmental cadmium exposure on the mortality of the general population in the Jinzu River basin. The survey was conducted over 6128 days from August 1, 1967 to May 10, 1984. The rural communities were divided into two groups, one with a cadmium concentration in rice of < 0.30 ppm and the other > or = 0.30 ppm. The influence of cadmium concentration in rice on mortality was analyzed using SMRs and a Cox's proportional hazards model. In both sexes, SMRs tended to be greater in the > or = 0.3 ppm group as compared to < 0.3 ppm group. The Cox hazard ratios for males and females in the > or = 0.30 ppm group, to those in the < 0.30 ppm group, were 1.42 and 1.10, respectively (significant in the men). Since the mean cadmium concentration in rice in each rural community was closely related to the development of renal injury, in regions with high cadmium concentrations in rice, the development of renal injury induced by cadmium is believed to be the factor underlying the increased mortality observed.

A retrospective study on the relation between renal dysfunction and cadmium concentration in rice in individual hamlets in the Jinzu River basin, Toyama Prefecture, Japan

Using as an index of exposure the Cd concentration in rice and as an index of health effect the urinary abnormality rate (proteinuria, glycosuria, and proteinuria with glycosuria) in the most systematic and extensive health screening examination conducted in 1967 and 1968 in the Jinzu River basin, Japan (a total of 13,183 subjects), we investigated whether a dose-response relationship exists between the two indices. For subjects that lived in the same hamlet since birth, with low Cd concentrations in rice it was confirmed that renal dysfunction does not develop unless the length of residence is prolonged, whereas with high Cd concentrations in rice renal dysfunction develops even when the length of residence is short. For subjects that lived in the same hamlet for over 30 years and that were aged over 50 years, the urinary abnormality rate in individual hamlets showed significant increases with increases in the mean Cd concentration in rice, demonstrating that a dose-response relationship existed. The allowable values of Cd concentration in rice were estimated to be in the range of 0.05-0.20 ppm, representing values lower than the 0.4 ppm provisionally adopted by the Japanese government.

Sacral meningeal cyst associated with valve-like mechanism--case report

A 58-year-old woman presented with low back pain radiating to the lower extremities. Magnetic resonance imaging revealed a cystic lesion in the sacrum compressing the nerve roots. At operation, a valve-like communication was found between the subarachnoid space and the cyst cavity in the vicinity of the sacral nerve root. The communication was obliterated with a purse-string suture and reinforced with a free muscle graft. Postoperatively, she reported improvement of the pain. Valve-like communication between the cyst cavity and subarachnoid space can cause enlargement of spinal meningeal cyst, and could also explain enlargement of sacral meningeal cyst. Surgical obliteration of the communication rather than the cyst resection is more important for sacral meningeal cyst.

Characterization of an isoform of rice starch branching enzyme, RBE4, in developing seeds

cDNA clones encoding an isoform of starch branching enzyme, RBE4, have been identified from a developing rice seed cDNA library, using a synthetic oligonucleotide probe corresponding to the N-terminal amino acid sequence of RBE4. The cDNA-derived amino acid sequence indicated that RBE4 is initially produced as a precursor protein of 841 amino acids, including a 53-residue transit peptide at the N-terminus. The mature form of RBE4 shared a high degree of sequence identity (80%) with mature RBE3, and possessed an N-terminal extra sequence, as found in RBE3. Northern blot analysis demonstrated that the RBE4 gene is expressed in both leaves and developing seeds. The RBE4 gene was distinguished from the RBE1 and RBE3 genes by expression at the earlier stages of seed development. To examine enzymatic functions of RBE4, recombinant proteins were produced in Escherichia coli cells, and purified by two chromatographic separations. The branched alpha-glucans produced by the recombinant enzymes from potato amylose revealed the different patterns of oligosaccharide chain transfer. The peak of major branches of the products by RBE3 or RBE4 was 6 glucose units, whereas the peaks of major branches of the products by RBE1 were 6 and 11 glucose units. The similar property between RBE3 and RBE4 is supported by high similarity of the amino acid sequences between them.

Alcohol consumption and blood pressure in Japanese men

In a study of Japanese men, a nonlinear association of alcohol consumption and blood pressure was not observed. This cross-sectional study was conducted to clarify the effect of infrequent or light alcohol consumption on blood pressure in normotensive Japanese men. The subjects were 2,179 male workers ranging in age from 40 to 54 years. Drinking habits were represented by three indices: episodic alcohol consumption, frequency of drinking, and monthly alcohol consumption. Seven items were analyzed as covariates: age, body mass index, salt intake, physical activity, and levels of gamma-glutamyl transpeptidase, uric acid, and plasma glucose. The association between drinking habits and blood pressure was evaluated by using analysis of covariance. Both episodic alcohol consumption and frequency of drinking were significantly associated with blood pressure in subjects aged 45 to 54 years. In those aged 40 to 44 years, there was a significant association between frequency of drinking and diastolic blood pressure. Significant associations of monthly alcohol consumption with blood pressure in every age group also were found. In subjects aged 45 to 54 years, linear associations between episodic alcohol consumption, frequency of drinking, monthly alcohol consumption, and adjusted blood pressure were observed. In those aged 40 to 44 years, nonlinear associations of monthly alcohol consumption and frequency of drinking with adjusted blood pressure were observed, and threshold effects of 540 ml of alcohol per month and a frequency of 1 to 12 days per month were found. In conclusion, habitual alcohol consumption increases blood pressure linearly in normotensive workers aged 45 to 54 years, although light consumption does not affect blood pressure in those aged 40 to 44 years.

Experimental small bowel transplantation using newborn intestine in rats: III. Long-term cryopreservation of rat newborn intestine

BACKGROUND

If long-term organ cryopreservation can be attained, a significant achievement will have been made to address the problem for donor shortage. Fetal intestine has been known to revascularize naturally without vascular anastmosis. The authors have confirmed previously that the newborn intestine also could develop to maturity in the host omentum. Here, the authors examined whether the cryopreserved newborn intestine could revascularize in the syngeneic combination using the 2 different solutions and whether cryopreservation affect their antigenicity in the allogeneic combination.

METHODS

Inbred rat strains of LEW (MHC haplotype; RT1(l)) and BN (RT1(n)) were used. LEW newborn intestinal grafts were stored in RPMI-1640 or University of Wisconsin solution with 10% DEMSO (n = 10 in each group). The grafts were placed into a cold (4 degrees C) preservation solution for 30 minutes and then placed into a freezing chamber and cooled to -80 degrees C at -1 degrees C/min after 12 hours quenched to -180 degrees C in liquid nitrogen for longer than 30 days. Then, the cryopreserved grafts under the 2 different solutions were transplanted syngenicaly (LEW to LEW). The cryopreserved BN grafts also were implanted into the LEW omentum pouch. The allotransplantation was received with a 14-day high-dose course of tacrolimus (0.64 mg/kg, intramuscularly). The grafts were evaluated histologically at 4 weeks after transplantation. Fresh newborn intestines implanted in this syngeneic and allogeneic combination were evaluated as each control group.

RESULT

In the syngeneic combination, more than 90% of the mature intestine were obtained. There was no significant difference among the different solution and the fresh group. However, in the allogeneic combination, both fresh and cryopreserved grafts were histologically poor.

CONCLUSIONS

This is the first report showing that long-term cryopreservation was not harmful for neovascularization of newborn intestine. Long-term cryopreservation did not reduce the antigenicity of the newborn intestine. J Pediatr Surg 36:602-604.

Furosemide-probenecid interaction as a laboratory exercise for undergraduate education in clinical pharmacology

OBJECTIVE

The aim of this study was to determine the easiness, reproducibility, and safety of a laboratory exercise for a drug interaction between furosemide and probenecid.

METHODS

From 1995 to 1999 approximately 100 medical students participated in the exercise each year after they gave written informed consent. The students were randomly assigned to one of the three groups in a double-blind fashion: group 1, placebo plus 20 mg of furosemide; group 2, 250 mg of probenecid plus 20 mg of furosemide; and group 3, 1000 mg of probenecid plus 20 mg of furosemide. The students took probenecid or its placebo 1 hour before furosemide. Urine volume and urinary sodium excretion were measured for 3 hours after furosemide. At the end of the exercise in 1999, students responded to several questionnaires concerning the utility of furosemide.

RESULTS

The entire course of the exercise was completed within half a day. The following findings were obtained every year. (1) Probenecid dose dependently blunted the diuretic effects of furosemide. (2) Time courses of the diuretic effects were altered by probenecid. Ten to twenty percent of the students had slight complaints but completed the exercise without any medications. Finally, more than 80% of the students considered the exercise to be useful.

CONCLUSIONS

The data suggest that the exercise of the drug interaction between furosemide and probenecid is easy to perform, reproducible, and safe. Through the experience of the laboratory exercise, students will develop an attitude to assess and estimate potential drug interactions before they prescribe drugs.

Hepatic lymphocyte transplantation in hyperbilirubinemic gunn rats

Hepatic lymphomyeloid cells (HLCs) are thought to contain liver stem cells. We investigated whether HLCs generated enzyme-producing cells in vivo. HLCs from normal Wistar/Shi rats and rats in which liver ischemia was induced using a portal clamp 4 days previously were studied histopathologically and characterized using flow cytometry. Splenic lymphocytes obtained from these animals were compared as a control. The proliferative activity of HLCs and splenic cells from both groups was also tested by stimulation with concanavalin A. HLCs contained a significantly higher number of NK-T cells and OV6+ cells compared with the splenic cells. The HLCs from rats in which liver ischemia was induced tended to have greater proliferative activity than those from normal rats, while the proliferative activity of splenic lymphocytes was impaired by liver ischemia. The HLCs obtained from Wistar/Shi rats with liver ischemia were then injected into hereditary hyperbilirubinemic Gunn rats to determine whether the HLCs generated enzyme-producing cells. After injection of these stimulated HLCs, the titer of serum bilirubin in the recipient rats was markedly reduced over a long time course (6.80+/-0.93 to 4.87+/-0.22 mg/dl after 1 month and 3.52+/-1.33 mg/dl after 6 months). The results of the present study indicate that HLCs have different populations than splenic cells, and ischemia-reperfusion of the liver increased their proliferative activity. HLC transplantation successfully reduced high bilirubin levels over a long time course.

Super-elastic property of Ti-Ni alloy for use in dentistry

The super-elasticity of Ti-Ni alloy was investigated in tensile and bending tests to evaluate the mechanical properties of the castings and heat treatment effect on the bending properties of the wires for new clinical applications of the alloy in prosthodontics and orthodontics. In terms of the tensile properties of the castings, apparent proof stress increased and elongation decreased with the small increase in nickel content or with the decrease in titanium purity. This result suggests that precise control of the materials is indispensable to utilize the super-elasticity in dental cast appliances. In terms of the bending properties of Ti-Ni alloy wires, low residual deflection and small load/deflection ratio were obtained by the second heat treatment between 733 and 813 K, which was found to be suitable for the shape memory treatment of orthodontic appliances. Moreover, the functional force was changeable within this treatment temperature range.

Seizure outcome and hippocampal atrophy in familial mesial temporal lobe epilepsy

OBJECTIVE

To describe the clinical, genetic and MR characteristics of patients with familial mesial temporal lobe epilepsy (MTLE).

DESIGN/METHODS

The familial occurrence of MTLE was identified by a systematic search of family history of seizures in patients followed in the authors' epilepsy clinic. All probands and, whenever possible, other affected family members underwent EEG and MR investigations.

RESULTS

Twenty-two unrelated families with at least two individuals with MTLE were identified by clinical and EEG findings. Ninety-eight individuals with history of seizures were evaluated. Sixty-eight patients fulfilled the diagnostic criteria for MTLE. MRI was performed in 84 patients, and showed hippocampal atrophy with increased T2 signal in 48 (57%). The distribution of hippocampal atrophy according to the seizure outcome groups was 6 of 13 patients (46%) with seizure remission, 16 of 31 (51%) with good seizure control under medication, and all 16 patients with refractory MTLE. Hippocampal atrophy was found also in patients that did not fulfill the criteria for MTLE: 3 of 10 (30%) patients with febrile seizure alone, 6 of 10 (60%) patients with recurrent generalized tonic-clonic seizures, and 1 of 4 (25%) patients with a single partial seizure.

CONCLUSION

Familial MTLE is a clinically heterogeneous syndrome. Hippocampal atrophy was observed in 57% of patients, including those with benign course or seizure remission, indicating that the relationship between hippocampal atrophy and severity of epilepsy might be more complex than previously suspected. In addition, these findings indicate the presence of a strong genetic component determining the development of mesial temporal sclerosis in these families.

Application of path analysis to urinary findings of cadmium-induced renal dysfunction

In order to identify some causal relations among various urinary indices of cadmium-induced renal dysfunction, such as glucose, total protein, amino nitrogen, beta 2-microglobulin (beta 2-m), metallothionein (MT), and cadmium (Cd), we applied path analysis method to previous epidemiological studies targeting the residents of the Cd-polluted Kakehashi River basin of Ishikawa Prefecture, Japan. We obtained a diagram-termed path model, representing some causal relations among the above urinary indices. It shows that urinary Cd is located at the beginning point in the diagram, and Cd-induced renal dysfunction develops in the following order: Cd exposure-->increase of beta 2-m and/or MT excretion-->increase of amino-N and/or total protein excretion-->increase of glucose excretion. It was proved mathematically, that in the case of both males and females, increased excretions of beta 2-m and/or MT were the most sensitive urinary indices of the early stage of chronic Cd-induced renal dysfunction.

[Simultaneous carotid and coronary artery surgery in asymptomatic carotid artery stenosis--report of three cases]

Some patients with coronary artery disease are diagnosed as having additional carotid artery disease. This subset of patients has been identified as a high-risk group for cardiac and cerebral complications following surgical intervention. Three patients who underwent combined CEA/CABG for coexistent asymptomatic carotid occlusive disease are reported. Case 1: A 69-year-old female who suffered chest pain on exertion. Her coronary angiogram showed severe stenosis of three vessels. Her carotid angiogram showed 98% stenosis of the right internal carotid artery and poor collateral circulation. The severe stenosis of her carotid artery was considered as a risk factor for perioperative cerebral stroke. Intraoperatively, CEA preceded the CABG. Postoperative course was uneventful. Case 2: A 64-year-old male. Intermittent claudication was his initial symptom. His coronary angiogram showed stenosis in three vessels and carotid angiogram showed 75% stenosis in the right carotid artery. Simultaneous CABG and CEA was performed. His postoperative course was uneventful. Case 3: A 62-year-old male whose ECG indicated ischemic heart disease, although he had no symptoms. His coronary angiogram showed stenosis in three vessels, and 80% stenosis of his right carotid artery was observed by carotid angiogram. He underwent simultaneous surgery, and had an uneventful postoperative course. It has been reported that 1.5-8.7% of CABG patients have severe carotid artery stenosis, and perioperative cerebral stroke occurs in 0.9-16%. Simultaneous surgery was successful in our three patients who had asymptomatic carotid artery stenosis. Using this surgical approach for critical coexistent disease may minimize the incidence of perioperative cerebrovascular complications in patients undergoing CABG.

Cysticidal therapy: impact on seizure control in epilepsy associated with neurocysticercosis

OBJECTIVE

To evaluate the clinical features and seizure control of epilepsy related to neurocysticercosis.

METHOD

18 patients with partial epilepsy and neurocysticercosis were treated with albendazol or praziquantel and followed from 3 months to 12 years. We analyzed results from the CSF exam, interictal electroencephalogram (EEG), head computerized tomography and/or magnetic resonance imaging.

RESULTS

The patients' mean age was 36.4 years. The mean duration of epilepsy was 16 years. 83% patients had simple partial seizures; 17% had complex partial seizures. All patients underwent routine EEGs: 62% had abnormalities and 38% were normal. A relationship was observed between focal EEG abnormality and the location of cyst in 28% of the patients. The CSF exams showed pleocytosis in 33% of the patients, and 28% had elevated protein levels. Only 22% of patients had positive titer for cysticercosis in the CSF. In all patients who had somatosensory and special sensory seizures there was a relationship between location of the cysts and seizure semiology (n=11). After cysticidal therapy, 83% patients had a significant improvement in controlling seizures.

CONCLUSION

In this group, we found a predominance of simple partial seizures and a relationship between somatosensory and special sensory seizures and the location of the cysts. Cysticidal therapy was effective in controlling seizures in these patients and should be considered for patients with partial seizures and semiology related to cyst location.

Quantitative trait loci (QTL) analysis in a Meishan x Göttingen cross population

In order to locate the genetic regions in the swine genome that are responsible for economically important traits, a resource population has been constructed by mating two female Meishan pigs with a male Göttingen miniature pig. In subsequent generations, 265 F2 offspring were produced from two F1 males and 19 F1 females. The F2 offspring were scored for eight traits including growth rate, teat number, vertebra number and backfat thickness, and genotyped for 318 genetic markers spanning the swine genome. Least-square analysis revealed quantitative trait loci (QTL) effects for vertebra number on chromosomes 1 and 2; for teat number on chromosomes 1 and 7; for birth weight on chromosome 1; for average daily gain between 4 and 13 weeks of age on chromosomes 9 and 10; for backfat thickness on chromosome 7; and for backskin thickness on chromosome 3.

Time-dependent nephrotoxicity associated with daily administration of cisplatin in mice

The chronopharmacokinetics and chronopharmacodynamics of cisplatin were studied in a mouse model to reveal the mechanisms of dosing time-dependent nephrotoxicity induced by daily administration. Chronotoxicity was tested by daily intraperitoneal injections of cisplatin (6mg kg(-1)) for 5 days at four time points (04:00, 10:00, 16:00 and 22:00h) in BALB/c mice (n = 6 in each group). After following the changes in body weight, serum concentrations of blood urea nitrogen (BUN) and creatinine obtained on day 6 were compared. The results showed diurnal variations in cisplatin toxicity, with the 04:00 and 16:00h time points the best and the worst, respectively. We then measured platinum concentrations in blood, liver and kidney and compared the results of the 04:00 and 16:00 h groups (n = 4 in each group). Kidney sensitivity to cisplatin alone, lipopolysaccharide (LPS) alone, cisplatin with LPS and saline (control) were also measured using a tissue culture system (a measurement system of interleukin-6 (IL-6) production) between the 04:00 and the 16:00 h groups (n = 4 in each group). These results showed no significant difference in platinum accumulation between the two groups. IL-6 production was higher in the 16:00 h group than in the 04:00 h group after saline injection alone (P < 0.05). Cisplatin treatment alone did not increase IL-6 production. However, IL-6 levels were markedly augmented by cisplatin with LPS. In conclusion, chrononephrotoxicity induced by daily cisplatin administration does not only depend on cisplatin accumulation, but might also depend on kidney sensitivity to diurnal variations in inflammatory reaction without direct cisplatin toxicity.

Long-term natural history of hemorrhagic moyamoya disease in 42 patients

OBJECT

The purpose of this study was to delineate the long-term natural history of hemorrhagic moyamoya disease (MMD).

METHODS

A retrospective review was conducted among 42 patients suffering from hemorrhagic MMD who had been treated conservatively without bypass surgery. The group included four patients who had undergone indirect bypass surgery after an episode of rebleeding. The follow-up period averaged 80.6 months. The clinical features of the first bleeding episode and repeated bleeding episodes were analyzed to determine the risk factors of rebleeding and poor outcome. Intraventricular hemorrhage with or without intracerebral hemorrhage was a dominant finding on computerized tomography scans during the first bleeding episode in 29 cases (69%). During the follow-up period, 14 patients experienced a second episode of bleeding, which occurred 10 years or longer after the original hemorrhage in five cases (35.7%). The annual rebleeding rate was 7.09%/person/year. The second bleeding episode was characterized by a change in which hemisphere bleeding occurred in three cases (21.4%) and by the type of bleeding in seven cases (50%). After rebleeding the rate of good recovery fell from 45.5% to 21.4% and the mortality rate rose from 6.8% to 28.6%. Rebleeding and patient age were statistically significant risk factors of poor outcome. All four patients in whom there was indirect revascularization after the second bleeding episode experienced a repeated bleeding episode within 8 years.

CONCLUSIONS

The occurrence of rebleeding a long time after the first hemorrhagic episode was not uncommon. Furthermore, the change in which hemisphere and the type of bleeding that occurred after the first episode suggested the difficulty encountered in the prevention of repeated hemorrhage.

Rat small intestinal transplantation: a comparison of the cuff and hand-suture methods

The rat model is ideal for investigating various reactions to small intestinal transplantation (SIT). The conventional surgical model (hand-suture method), however, requires microsurgical techniques and remains difficult for beginners to perform at a high success rate. We have employed the SIT model using the cuff method, by which the vessels are anastomosed without sutures. All of the fellows who used the hand-suture models needed over 8 +/- 5.8 months until they achieved a 70% success rate. In contrast, the fellows employing the cuff method mastered SIT models after 6 weeks' practice. The cuff technique is a simplified and quickly mastered alternative to the hand-suture method that may be desirable for researchers who wish to apply the method to SIT experiments and whose primary purpose is not microsurgery.

Prevention of cerebrospinal fluid leakage and delayed loss of preserved hearing after vestibular schwannoma removal: reconstruction of the internal auditory canal in the suboccipital transmeatal approach--technical note

The suboccipital transmeatal approach uses packing of a muscle or fat graft into the internal auditory canal (IAC) to prevent postoperative cerebrospinal fluid (CSF) leakage. However, preserved hearing after removal of vestibular schwannomas may decline over time because of the progressive constriction of cochlear vascular supply due to scarring of the IAC. We propose a surgical technique for IAC reconstruction, which separates the preserved cochlear nerve and vasculature from the graft, and regains the CSF space in the IAC. Prior to the drilling of the posterior wall of the IAC, the dura mater of the petrous bone forming the posterior wall of the IAC is harvested for IAC reconstruction. After completion of tumor removal, a "roof" of the IAC is reconstructed using the dura mater, and a muscle or fat graft soaked with fibrin glue is placed on the "roof" of the IAC. The IAC was reconstructed using this technique in 26 consecutive patients with vestibular schwannomas who underwent tumor removal via the suboccipital transmeatal approach. Postoperative magnetic resonance imaging confirmed the regained CSF space in the IAC. No delayed hearing loss occurred in four patients with preserved hearing. No CSF leakage occurred after surgery. This new technique of IAC reconstruction may prevent delayed hearing loss as well as postoperative CSF leakage after removal of vestibular schwannomas via the suboccipital transmeatal approach.

Preoperative assessment of trigeminal neuralgia and hemifacial spasm using constructive interference in steady state-three-dimensional Fourier transformation magnetic resonance imaging

Results of microvascular decompression (MVD) for trigeminal neuralgia (TN) and hemifacial spasm (HFS) may be improved by accurate preoperative assessment of neurovascular relationships at the root entry/exit zone (REZ). Constructive interference in steady state (CISS)-three-dimensional Fourier transformation (3DFT) magnetic resonance (MR) imaging was evaluated for visualizing the neurovascular relationships at the REZ. Fourteen patients with TN and eight patients with HFS underwent MR imaging using CISS-3DFT and 3D fast inflow with steady-state precession (FISP) sequences. Axial images of the cerebellopontine angle (CPA) obtained by the two sequences were reviewed to assess the neurovascular relationships at the REZ of the trigeminal and facial nerves. Eleven patients subsequently underwent MVD. Preoperative MR imaging findings were related to surgical observations and results. CISS MR imaging provided excellent contrast between the cranial nerves, small vessels, and cerebrospinal fluid (CSF) in the CPA. CISS was significantly better than FISP for delineating anatomic detail in the CPA (trigeminal and facial nerves, petrosal vein) and abnormal neurovascular relationships responsible for TN and HFS (vascular contact and deformity at the REZ). Preoperative CISS MR imaging demonstrated precisely the neurovascular relationships at the REZ and identified the offending artery in all seven patients with TN undergoing MVD. CISS MR imaging has high resolution and excellent contrast between cranial nerves, small vessels, and CSF, so can precisely and accurately delineate normal and abnormal neurovascular relationships at the REZ in the CPA, and is a valuable preoperative examination for MVD.

Sequence analysis of porcine polymeric immunoglobulin receptor from mammary epithelial cells present in colostrum

The composition of colostrum is quite different from that of mature milk. In particular, colostrum contains relatively high concentrations of proteins responsible for the immunological defence of newborns, such as lactoferrin, lactoperoxidase, lysozyme and immunoglobulins (Farkye, 1992; Cals et al. 1994; Telemo & Hanson, 1996; Wang et al. 1997). Whereas lactoferrin and lactoperoxidase are synthesized in mammary epithelial cells (Cals et al. 1994; Molenaar et al. 1996), the immunoglobulins are derived from blood serum (Larson, 1992). Immunoglobulin A (IgA), predominantly found in milk, participates in the development of the gastrointestinal system and the immune system in newborn infants. It is transported by a system that involves formation of a complex with the polymeric IgA receptor (pIgR) exposed on the basolateral aspect of mammary gland epithelial cells, followed by internalization and release into milk as secretory IgA (Rosato et al. 1995; De Groot et al. 1999). Consequently, expression of pIgR in mammary epithelial cells also contributes to the development of the immune system. These proteins specifically expressed in the early stage of lactation are of interest. However, few studies have been carried out compared with those focusing on the major proteins in mature milk, in part owing to problems of mammary gland availability.

Imamura et al. (1996) reported the isolation of mRNA from bovine mammary epithelial cells derived from colostrum and showed that it is possible to detect αs1-casein mRNA, predominantly expressed in the bovine mammary gland, through the application of reverse transcriptase polymerase chain reaction (RT-PCR). We have applied this procedure to porcine colostrum, and successfully analysed the coding sequence of pIgR. In this paper we describe the possibility of detecting gene expression in mammary epithelial cells present in colostrum and the porcine pIgR sequence obtained is compared with those of other animal species.

Effect of fibrin glue on small and large bowel anastomoses in the rat

Fibrin glue has been used as a hemostatic and adhesive agent for many years, but its efficacy in digestive surgery is still controversial. In this study, we evaluated the effect of fibrin glue on the healing of the small and large bowel anastomotic portions by measurement of the anastomotic bursting pressure. Further, the efficacy of fibrin glue in preventing intra-abdominal adhesion formation was assessed. Our results indicated that fibrin glue enhanced the resistance towards an elevation of intraluminal pressure in small bowel, but not in large bowel. Concomitantly, the glue did not significantly attenuate postoperative adhesion formation. A sealing action of fibrin glue might protect against bleeding and microleakage, resulting in beneficial effects on small bowel anastomosis.

Effects of dosing time and schedule on cisplatin-induced nephrotoxicity in rats

Renal dysfunction induced by a single injection of cisplatin depends on the timing of the dose. However, the effects of repeated administration of cisplatin on time-dependent toxicity have not been evaluated despite the fact that in clinical practice high doses are repeatedly injected at intervals or low doses are administered daily. We studied chrononephrotoxicity in rats after weekly or daily cisplatin injections. Weekly high doses (5 mg kg(-1)) or daily low doses (1.2 mg kg(-1)) of cisplatin were injected at four time points (3, 9, 15 and 21 h after the light was turned on (HALO)) for 3 weeks. Changes in body weight after weekly cisplatin administration were independent of the timing of the doses. In the group that received daily cisplatin, the loss in body weight in the 3 HALO group was smaller than in animals receiving injections at 15 and 21 HALO (P < 0.05 and 0.001, respectively). The blood urea nitrogen and serum creatinine levels in the control rats showed a significant circadian change (peak at 15 HALO and trough at 9 HALO), but these parameters were markedly elevated in both trials and their circadian variations were disturbed. In conclusion, cisplatin-induced nephrotoxicity was the lowest at 3HALO compared with other time points of both dose regimens.

[Familial partial epilepsies]

OBJECTIVE

To investigate the clinical and genetic characteristics of familial partial epilepsies.

METHOD

Family history of seizures was questioned in all patients followed in our epilepsy clinics, from October 1997 to December 1998. Those with positive family history were further investigated and detailed pedigrees were obtained. All possibly affected individuals available underwent clinical evaluation. Seizures and epilepsy syndromes were classified according to the ILAE recommendations. Whenever possible, EEG and MRI were performed.

RESULTS

Positive family history was identified in 32 unrelated patients. A total of 213 possibly affected individuals were identified, 161 of whom have been evaluated. The number of affected subjects per family ranged from two to 23. Temporal lobe epilepsy (TLE) was identified in 22 families (68%), frontal lobe epilepsy in one family (3%), partial epilepsy with centrotemporal spikes in five families (15%), and other benign partial epilepsies of childhood in four families (12%). Most of the affected individuals in the TLE families (69%) had clinical and/or EEG characteristics of typical TLE. However, the severity of epilepsy was variable, with 76% of patients with spontaneous seizure remission or good control with medication and 24% with refractory seizures, including 7 patients that underwent surgical treatment. In the other 10 families, we identified 39 possibly affected subjects, 23 of whom were evaluated. All had good seizure control (with or without medication) except for one patient with frontal lobe epilepsy. Pedigree analysis suggested autosomal dominant inheritance with incomplete penetrance in all families.

CONCLUSION

Family history of seizures is frequent among patients with partial epilepsies. The majority of our families had TLE and its expression was not different from that observed in sporadic cases. The identification of genes involved in partial epilepsies may be usefull in classification of syndromes, to stablish prognosis and optimal treatment.

Renal effects of cadmium exposure in cadmium nonpolluted areas in Japan

Long-term exposure to cadmium (Cd) causes renal damage in the general population. The maximum allowable urinary Cd concentration, which was calculated from our previous study performed in a Cd-polluted area, was almost the same as the mean urinary Cd concentration of people living in nonpolluted areas. We assessed whether environmental Cd exposure is related to renal dysfunction of people in nonpolluted areas in Japan. Blood and urine samples were collected from 2753 subjects (1105 men and 1648 women) ages over 50 years old in three nonpolluted areas. Blood was analyzed for Cd and urine was analyzed for Cd, total protein, beta(2)-microglobulin (beta(2)-mg), and N-acetyl-beta-D-glucosaminidase (NAG). Cd in blood or urine was employed as indicators of internal dose; and urinary total protein, beta(2)-mg, and NAG were used as an indicator of renal dysfunction. Multiple regression analysis and logistic regression analysis were performed to clarify the dose-effect and dose-response relationship between blood or urinary Cd concentration and indicators of renal dysfunction. Multiple regression analysis demonstrated a significant dose-effect relationship between Cd in blood and urine and indicators of renal dysfunction. Logistic regression analysis also showed that the probability that individual subjects would have abnormal values of the renal variables was significantly related to Cd in blood and urine.

Mapping and determination of the cDNA sequence of the Erc gene preferentially expressed in renal cell carcinoma in the Tsc2 gene mutant (Eker) rat model

The Eker rat develops hereditary renal carcinomas (RCs) due to two hit mutations of the tumor suppressor gene, Tsc2. We previously identified using representational difference analysis (RDA), four genes that were expressed more abundantly in an Eker rat RC cell line than in normal kidney tissue. One gene, Erc (expressed in renal carcinoma) showed sequence homology to the mouse and human megakaryocyte potentiating factor (MPF)/mesothelin gene. The present study determines the full sequence of the cDNA and the exon-intron structure of the rat Erc gene and maps its locus in the chromosome by fluorescence in situ hybridization. Rat Erc and its human homologue were localized in chromosomes 10q12-21 and 16p13.3, respectively, both of which coincided with the locus of the Tsc2/TSC gene. We also found that Erc was expressed at higher levels in primary RCs compared with the normal kidney of the Eker rat. Erc may be related to carcinogenesis in the Tsc2 gene mutant (Eker) rat model.

Interhemispheric subdural hematoma caused by a ruptured internal carotid artery aneurysm: case report

BACKGROUND

Interhemispheric subdural hematoma (ISH) usually occurs after head trauma; nontraumatic ISH is extremely rare.

CASE DESCRIPTION

The authors describe a 62-year-old male presenting with severe headache and ptosis on the left side. Computed tomography (CT) and magnetic resonance imaging disclosed a hematoma in the interhemispheric subdural space without subarachnoid hemorrhage. Cerebral angiography revealed an aneurysm arising from the left internal carotid-posterior communicating artery (IC-PC) junction. The patient underwent emergency clipping of the aneurysm and was discharged without neurological deficit.

CONCLUSION

Ruptured aneurysms resulting in ISH without subarachnoid hemorrhage have been reported in only a few cases; this is the second case to describe the association of a ruptured IC-PC aneurysm with an ISH. The etiology of ISH formation due to ruptured aneurysms and the diagnosis are discussed.

Synthesis and antitumor activity of duocarmycin derivatives: A-ring pyrrole compounds bearing beta-(5',6',7'-trimethoxy-2'-indolyl)acryloyl group

A series of A-ring pyrrole derivatives of duocarmycin bearing beta-(5',6',7'-trimethoxy-2'-indolyl)acryloyl group were synthesized, and evaluated for in vitro anticellular activity against HeLa S3 cells and in vivo antitumor activity against murine sarcoma 180 in mice. New Seg-B analogues bearing beta-(5',6',7'-trimethoxy-2'-indolyl)acryloyl group containing double bond as spacer had lower peripheral blood toxicity than the derivatives bearing 5',6',7'-trimethoxyindole-2'-carboxyl group in Seg-B of the natural type. Moreover, most of them exhibited potent antitumor activity against in vivo murine tumor models.

Auxiliary heterotopic liver transplantation in the rat: a simplified model using cuff technique and application for congenitally hyperbilirubimemic Gunn rat

To study the immunological and metabolic effects of auxiliary liver transplantation (ALT), a simple ALT model in rats was developed using the cuff application. Effects of transient parking of normal liver were tested in congenitally hyperbilirubinemic Gunn rats. Serum bilirubin concentrations in Gunn rats, transplanted heterotopically with normal livers of Wistar rats, were dramatically reduced and maintained within normal levels. The graftectomy was performed safely 1 month after transplantation, but total bilirubin levels did not return to the preoperative value of the Gunn rats. It is possible that hepatic stem cells included in ALT liver migrated to the host liver and differentiated into cells capable of producing certain enzymes.

New technique of complete thymectomy in adult rats without tracheal intubation

Adult rat thymectomy is frequently performed as part of the protocol for experiments in transplant immunology. Current methods used are either imprecise (suction methods) or require tracheal intubation (surgical technique) and are thus difficult to master. We have developed a safe technique of surgical removal of the thymus with resolution of any pneumothorax by suction through the xyphoid insertions of the diaphragm. This method is easy to learn and gives a 95% success rate.

Antibody formation in the transplanted spleen: a simple method of splenic transplantation in the rat using the cuff technique

To study whether transplanted spleens produce antibodies or not, a simplified model of spleen transplantation using the cuff technique was developed. The whole spleen with vascular pedicles was implanted in the syngeneic DA (RT1a) rat combination, using the cuff technique applied to the renal artery and vein of the recipient. The functions of the grafted spleen were tested by antibody formation-titers of antibody in the serum and plaque-forming cells in the graft spleen against xenogeneic [BALB/c (H-2d) mouse] antigen. The grafted spleens included a number of plaque-forming cells, as did the host spleen. This report shows direct evidence that vascularized splenic grafts produced antibodies. The technique is described in detail.

Detailed modified technique for safer harvesting and preparation of liver graft in the rat

Liver procurement and preparation for orthotopic liver transplantation (OLT) in the rat is the first stage for beginners aiming to acquire mastery of this model. It requires extensive and precise dissection in which each detail must provide security for the procurement and perfection for the future graft. Many technical details, "tricks and secrets," remain known only by expert teams, so that the learning phase can be long or unsuccessful if a period in such a team is not possible. We describe this procedure in great detail, including many improvements to the original technique. Complete illustration is provided to enable an easier appreciation of what remains the critical first part of the most difficult transplant model to perform in the rat.

Technical details for safer venous and biliary anastomoses for liver transplantation in the rat

Although orthotopic liver transplantation in the rat is a well-established experimental model, no detailed illustrated description of the procedure is available in the literature. As a result, achieving success in the technique without prolonged learning time requires training in specialized centers where the step-by-step details essential to success in the technique can be learnt. The aim of this paper is to provide beginners with the culminative experience of 15 years of improvements made to Kamada's original model, clearly illustrating the necessary steps and fine detail of each anastomosis to help beginners avoid unnecessary complications. We hope that this complete description of orthotopic liver transplantation in the rat, which remains the most difficult rodent transplant model to master, will greatly help microsurgeons acquire this demanding procedure.

Stress transmission through Ti-Ni alloy, titanium and stainless steel in impact compression test

Impact stress transmission of Ti-Ni alloy was evaluated for biomedical stress shielding. Transformation temperatures of the alloy were investigated by means of DSC. An impact compression test was carried out with use of split-Hopkinson pressure-bar technique with cylindrical specimens of Ti-Ni alloy, titanium and stainless steel. As a result, the transmitted pulse through Ti-Ni alloy was considerably depressed as compared with those through titanium and stainless steel. The initial stress reduction was large through Ti-Ni alloy and titanium, but the stress reduction through Ti-Ni alloy was more continuous than titanium. The maximum value in the stress difference between incident and transmitted pulses through Ti-Ni alloy or titanium was higher than that through stainless steel, while the stress reduction in the maximum stress through Ti-Ni alloy was statistically larger than that through titanium or stainless steel. Ti-Ni alloy transmitted less impact stress than titanium or stainless steel, which suggested that the loading stress to adjacent tissues could be decreased with use of Ti-Ni alloy as a component material in an implant system.

Polyphenols from Eriobotrya japonica and their cytotoxicity against human oral tumor cell lines

Three new flavonoid glycosides, together with 15 known flavonoids, have been isolated from the leaves of Eriobotrya japonica, and characterized as (2S)- and (2R)-naringenin 8-C-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosides, and cinchonain Id 7-O-beta-D-glucopyranoside, respectively, based on spectral analyses including two dimensional (2D) NMR techniques. Higher proanthocyanidin fraction in the water-soluble portion of the extract was characterized as a procyanidin oligomer mixture mainly composed of undecameric procyanidin. These polyphenols have also been assessed for cytotoxic activity against two human oral tumor (human squamous cell carcinoma and human salivary gland tumor) cell lines. Selective cytotoxicity of the procyanidin oligomer between tumor and normal gingival fibroblast cells, and its possible mechanism, were also described.

Direct immunization of malaria DNA vaccine into the liver by gene gun protects against lethal challenge of Plasmodium berghei sporozoite

The liver is the first target organ for malaria parasites immediately after the bite of an infected mosquito. We studied local immunization of malaria DNA vaccines at the site of the liver using a gene gun as a useful tool for in vivo transfection of foreign genes. A malaria DNA vaccine consisting of the Plasmodium berghei circumsporozoite protein (PbCSP) gene plus the mouse IL-12 gene was bombarded directly by a gene gun into mouse liver once or into the skin twice. A marked protective effect was induced by gene bombardment into the liver (more than 71%) compared with that into the skin (less than 33%). A Th1-type immune response and high production of iNOS were observed in the hepatic lymphocytes from mice bombarded into the liver, resulting in more effective protection compared with those bombarded into the skin. These results provide an important implication on the development of efficient malaria vaccine strategies.

Changes of lead levels in 24-h urine from 1985 to 1998 in Japanese adults

To determine whether current environmental lead (Pb) levels are causing any progressive changes in urinary Pb levels, 24-h urine samples were collected from 277 subjects (159 men and 118 women) in 1985, 312 subjects (155 men and 157 women) in 1993, and 311 subjects (156 men and 155 women) in 1998. All of the subjects worked in the same factory. The urinary Pb concentration was analyzed by flameless atomic absorption spectrophotometry. The geometric means for men were 4.74, 2.67 and 1.31 microg/day; 3.17, 1.78 and 1.04 microg/g creatinine; and 3.18, 1.99 and 0.98 microg/l urine in 1985, 1993 and 1998, respectively. The values for women were 3.22, 2.14 and 0.97 microg/day; 3.35, 2.26 and 1.15 microg/g creatinine; and 2.49, 1.86 and 0.83 microg/l urine, respectively. These results demonstrated that Pb levels in 24-h urine decreased significantly in the 13-year period (P<0.01).

Renal effects of cadmium intake of a Japanese general population in two areas unpolluted by cadmium

Renal effects of cadmium exposure (i.e., in food products) on people living in two areas unpolluted by cadmium in Japan were investigated. The population comprised 875 inhabitants (i.e., 346 males and 529 females) and 635 inhabitants (i.e., 222 males and 413 females), all of whom in each area were 50+ y of age. The authors used urinary cadmium concentration as an indicator of internal dose, and total urinary protein, beta2-microglobulin, and N-acetyl-beta-glucosaminidase were indicators of renal dysfunction. The authors used multiple-regression and logistic-regression analyses to study the relationship between urinary cadmium excretion and the above indicators of renal dysfunction. In the two geographic areas, both analyses revealed that urinary cadmium concentrations were associated significantly with indicators of renal dysfunction. The results suggest that renal dysfunction is related significantly with environmental cadmium exposure in areas of Japan that are not polluted by cadmium.

Magnetic resonance imaging in the evaluation of patients with aseptic meningoencephalitis and connective tissue disorders

OBJECTIVE

To describe the role of magnetic resonance imaging (MRI) in the evaluation of patients with chronic and recurrent aseptic meningitis.

METHOD

A retrospective study of five patients with aseptic meningoencefalitis diagnosed by clinical and CSF findings. CT scans showed without no relevant findings.

RESULTS

MRI showed small multifocal lesions hyperintense on T2 weighted images and FLAIR, with mild or no gadolinium enhancement, mainly in periventricular and subcortical regions. Meningoencephalitis preceded the diagnosis of the underlying disease in four patients (Behçet's disease or systemic lupus erythematosus). After the introduction of adequate treatment for the rheumatic disease, they did not present further symptoms of aseptic meningoencephalitis.

CONCLUSION

Aseptic meningoencephalitis can be an early presentation of an autoimmune disease. It is important to emphasize the role of MRI in the diagnosis and follow-up of these patients.

Synthesis and antitumor activity of duocarmycin derivatives: modification at C-8 position of A-ring pyrrole compounds bearing the simplified DNA-binding groups

A series of the 8-O-substituted A-ring pyrrole derivatives of duocarmycin bearing the simplified DNA-binding moieties such as cinnamoyl or heteroarylacryloyl groups were synthesized, and evaluated for in vitro anticellular activity against HeLa S3 cells and in vivo antitumor activity against murine sarcoma 180 in mice. In addition, the stability of the 8-O-substituted analogues in aqueous solution and the conversion to their active form (cyclopropane compound) from the 8-O-substituted analogues in mice or human serum were examined. The 8-O-substituted A-ring pyrrole derivatives bearing the simplified DNA-binding moieties showed remarkably potent in vivo antitumor activity and low peripheral blood toxicity compared with the 8-O-substituted A-ring pyrrole derivatives having the trimethoxyindole skeleton in segment-B (Seg-B), which were equal to 8-O-[(N-methylpiperazinyl)carbonyl] derivatives of 4'-methoxycinnamates and 4'-methoxy-beta-heteroarylacrylates. Moreover, among 8-O-substituted analogues, several compounds can be chemically or enzymatically converted to their active form in human serum. This result indicated that new 8-O-substituted derivatives were different prodrugs from KW-2189 and 8-O-substituted analogues being the same type of prodrug as KW-2189.

Synthesis of regioselectively protected forms of cytidine based on enzyme-catalyzed deacetylation as the key step

N4-Acetylcytidine (77%) and 2',3'-O, N4-triacetylcytidine (95%) were obtained from the hydrolysis of a common precursor, the peracetylated form of cytidine with Aspergillus niger lipase (Amano A) and Burkholderia cepacia esterase (SC esterase S), respectively, under very mild conditions. The experimental procedure for the conversion of triacetylcytidine to a corresponding phosphoramidite (82%), an intermediate for sugar nucleotide synthesis, is also elaborated.