In vivo and in vitro efficacy of capecitabine (X) + tamoxifen (TAM) in breast cancer (BC)

21092

Background: In vitro studies in BC cell lines suggested antagonism between TAM and 5-FU. Thymidine phosphorylase (TP) activates X to 5-FU in tumors. X activity correlates with tumor TP concentrations in vivo. Methods: We studied antitumor efficacy of X + TAM in vivo and in vitro in human BC models. Nude mice were inoculated s.c. with estradiol, then MCF-7 cells 1 day later. When tumors were ∼300 mm3, mice received 6 weeks’ oral vehicle (control), X (d1–14 q21d) at MTD (539 mg/kg) or 2/3 MTD, and/or TAM at 100 or 30 mg/kg/d. We also analyzed impact of 5-FU and doxifluridine (5'-DFUR, an intermediate of X) + TAM on estrogen receptor (ER) signals in an in-vitro culture system. ER signals were monitored by expression of green fluorescent protein (GFP) in MCF-7 BC cells transfected with the estrogen-responsive element (ERE)-GFP gene (MCF-7-E10). GFP expression was induced in MCF-7-E10 cells in the presence of estradiol at 3 pM or BC tissue supernatant. Results: X at 2/3 MTD + TAM 30 mg/kg were significantly more active than the highest dose of X or TAM alone. Tumor TP concentrations were significantly higher in TAM- than vehicle-treated mice. In the ER signal system, GFP expression of MCF-7-E10 was reduced by 4-hydroxytamoxifen (4-OHT, active form of TAM) at 0.01 and 0.1 nM. When added to 4-OHT, 5-FU 0.3–30 μM or 5'-DFUR 3–10 μM reduced GFP expression more than either agent alone. In vitro, 5-FU and 5'-DFUR inhibited proliferation of MCF-7-E10 cells regardless of 4-OHT. Additive effects could not be confirmed as 4-OHT alone showed only marginal anti- proliferative activity at 0.01–0.1 nM. Conclusion: X and TAM are not antagonistic in this model. TAM may augment X activity via TP upregulation in BC tissues. TAM and X intermediates showed no clear antagonism in vitro in an ER signal system. All-oral X + TAM merits evaluation as combination therapy in breast cancer.

[Table: see text]

Vestibular function and vasopressin

OBJECTIVE

To investigate the relation between the vestibular system and vasopressin (AVP).

MATERIAL AND METHODS

We examined the effects of electrical and caloric vestibular stimulation on plasma AVP levels in anesthetized rats. Plasma AVP levels of patients with intractable Ménière's disease who were subjected to endolymphatic drainage and steroid instillation surgery (EDSS) or intratympanic gentamicin (GM) injection were measured before and after these interventions.

RESULTS

Electrical vestibular stimulation increased plasma AVP levels in a current intensity-dependent manner. Plasma AVP levels were also increased by caloric stimulation with cold water. Plasma AVP levels decreased rapidly after EDSS, and were maintained at a low level even 6-12 months following EDSS or intratympanic GM injection.

CONCLUSIONS

Vestibular activation or inhibition-induced imbalance of intervestibular activities increased plasma AVP levels in rats. Therefore, vestibular disorder would seem to increase plasma AVP and thus worsen endolymphatic hydrops. EDSS rapidly decreased plasma AVP and would seem to reduce hydrops. Inhibition of vertigo spells by EDSS or intratympanic GM injection would reduce a possible stress response, resulting in a decrease in plasma AVP levels a long time after the treatments. This resultant decrease in AVP would beneficially inhibit the formation and/or maintenance of hydrops and thus prevent vertigo spells.

Human beta-defensin-2 induction in Helicobacter pylori-infected gastric mucosal tissues: antimicrobial effect of overexpression

The objective of this study was to understand more of the innate immune response to Helicobacter pylori by determining the expression of human beta-defensin-2 (hBD-2) in various gastric mucosal tissues and MKN45 gastric cancer cells with or without H. pylori. Semi-quantitative TaqMan RT-PCR and immunohistochemistry were carried out. The antimicrobial effects of a transfected hBD-2 gene against H. pylori were also evaluated. The results showed that hBD-2 was expressed in inflamed gastric mucosal tissues with H. pylori infection, but not in the absence of H. pylori infection. Expression was also detected in gastric cancers in patients with H. pylori infection. Expression was induced in the MKN45 gastric cancer cell line by H. pylori in a manner dependent on the abundance of bacteria. hBD-2-transfected 3T3J2-1 cells secreted hBD-2 protein into the culture medium and this protein inhibited growth of H. pylori completely. The results suggest that hBD-2 may be involved in the pathophysiology of H. pylori-induced gastritis.

Comparison of arbitrarily primed-polymerase chain reaction and pulse-field gel electrophoresis for characterizing methicillin-resistant Staphylococcus aureus

AIMS

The aim of this study was to analyse genotypes for clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA), including hetero-vancomycin-resistant Staph. aureus (VRSA), at a Japanese university hospital.

METHODS AND RESULTS

Seventy-eight clinical isolates of MRSA were analysed by arbitrarily primed-polymerase chain reaction (AP-PCR) using ERIC2 primer and by pulse-field gel electrophoresis (PFGE) following SmaI digestion. Analyses of the nine genotypes and 28 subtypes defined by PFGE, and of the three genotypes and 22 subtypes defined by AP-PCR, both facilitated epidemiological tracing. Used in combination, AP-PCR and PFGE provided more precise classification than the use of a single genotyping method. The six hetero-VRSA isolates were classified into four genotypes defined by the combination of both methods, but these genotypes contained non-VRSA isolates.

CONCLUSIONS

The results suggest that both PFGE and AP-PCR are useful in discriminating MRSA, but not hetero-VRSA, isolates for epidemiological analysis.

SIGNIFICANCE AND IMPACT OF THE STUDY

Combining the results of PFGE with the results of AP-PCR can provide more detail differentiation of MRSA and hetero-MRSA isolates than either method alone.

[An electrophysiological study of ropivacaine on excised cervical vagus nerves of rabbit]

Ropivacaine, a new long acting local anaesthetic of amide type is structurally related to mepivacaine and bupivacaine. This study was designed to compare the in vitro potency and neurotoxicity of ropivacaine with those of other commercially available local anaesthetics using an isolated rabbit vagus nerve model. Ropivacaine dose-dependently suppressed the evoked compound action potentials of A beta nerve and C nerve components. Minimum concentration of ropivacaine for producing complete suppression of the compound action potentials of all components was 0.008%. Electron microscopic observation showed that ropivacaine did not destroy any peripheral nervous structures in concentrations up to 0.75%. When the neurotoxic effect of ropivacaine was compared, in terms of risk ratio (clinically used concentration/concentrations producing 2 hr irreversible block), with that of commercially available local anesthetics, the rank oder was dibucaine, tetracaine, lidocaine, bupivacaine and ropivacaine.

Midcalf ultrasonography for the diagnosis of ruptured Baker's cysts

Clinically significant and palpable enlargement of the gastrocnemio-semimembranosus bursa is known as a Baker's cyst. Baker's cysts may rupture, resulting in a swollen, painful leg that is clinically indistinguishable from acute deep vein thrombosis. For this reason, ruptured Baker's cysts are sometimes called pseudothrombophlebitis. The purpose of this study was to determine the incidence of ruptured Baker's cysts, and to evaluate the role of ultrasonography in the diagnosis of this condition. The hospital records of 106 patients (43 men and 63 women) who were referred to the vascular surgical department at Saitama Medical Center with unilateral or bilateral swollen legs between June 1997 and June 2000 were reviewed retrospectively. The total number of affected limbs was 125, being 52 right legs and 73 left legs. Deep vein thrombosis was the most common cause of swollen legs, being diagnosed in 44.8%. No specific anatomical derangement was found in 39 limbs (31.2%), and these were defined as idiopathic. Lymphedema was also common, being diagnosed in 16 limbs. Ruptured Baker's cysts were observed in three limbs, with an incidence of 2.4%. In all of these patients, a large hypoechoic space was seen behind the calf muscles and this sonolucent area was easily detected by a conventional scanner, being pathognomonic of a ruptured Baker's cyst.

Augmentation of megakaryocytopoiesis within the hematopoietic microenvironment of human granulocyte colony-stimulating factor transgenic mice

OBJECTIVE

Megakaryocytopoiesis was dramatically augmented in human granulocyte colony-stimulating factor transgenic mice (G-Tg) compared to littermates. We examined the characteristics of megakaryocytes and megakaryocyte progenitor cells in these mice.

MATERIALS AND METHODS

The numbers of colony-forming unit megakaryocytes (CFU-MK) and megakaryocytes in hematopoietic organs were counted. The megakaryocytes of G-Tg were examined ultrastructurally, and bone marrow transplantation studies using congenic G-Tg (Ly5.2) and C57BL/6 (Ly5.1) were performed. The number of day-14 colony-forming unit spleen (CFU-S) that contained megakaryocytes in [Ly5.1 > G-Tg] and [G-Tg > Ly5.1] mice also was counted.

RESULTS

The number of CFU-MK increased markedly in the spleen, bone marrow, and peripheral blood. The number of megakaryocytes in the spleen and bone marrow also were increased in G-Tg mice. Ultrastructural analyses revealed that megakaryocytes in G-Tg mice were immature. Bone marrow transplantation studies of [Ly5.1 > G-Tg] mice resulted in a significantly increased number of megakaryocytes compared to [G-Tg > Ly5.1] mice. The number of day-14 CFU-S that contained megakaryocytes was increased markedly in [Ly5.1 > G-Tg] mice compared to [G-Tg > Ly5.1] mice. In vitro differentiation of megakaryocytes in [Ly5.1 > G-Tg] mice was induced by interleukin-11 and thrombopoietin.

CONCLUSION

The results showed that the hematopoietic marrow microenvironment of G-Tg is important in augmenting megakaryocytopoiesis. [Ly5.1 > G-Tg] mice are potentially useful as a source of murine megakaryocytes and their progenitors.

[Endolymphatic sac drainage and steroid-instillation surgery (EDSS) for intractable Meniere's disease]

Endolymphatic sac surgery is one of the most widely accepted techniques used to treat intractable Meniere's disease. To improve this surgery, we developed the following techniques: A simple mastoidectomy was used to expose the endolymphatic sac between the sigmoid sinus and inferior margin of the posterior semicircular canal. The sac was opened and filled with a mass of prednisolone. A bundle of absorbable gelatin films was then inserted into the sac lumen to expand it, followed by gelatin sponges dipped in a high concentration of dexamethasone. Long-term results (17-32 months) in 20 patients with intractable Meniere's disease treated with endolymphatic sac drainage and steroid-insertion surgery (EDSS) showed that definitive spells were completely controlled in 15 of 20 cases (75%); all reports of vertigo decreased; hearing improved in 12 of 20 cases (60%); and annoyance due to tinnitus decreased in 15 of 20 cases (75%). Steroids directly instilled into the endolymphatic cavity may thus be more effective with the diseased inner ear organs than those applied via any other route. Draining of endolymphatic fluid at the sac into the mastoid cavity also contributed to these satisfactory EDSS results.

Large-scale cDNA analysis of the maternal genetic information in the egg of Halocynthia roretzi for a gene expression catalog of ascidian development

The ascidian egg is a well-known mosaic egg. In order to investigate the molecular nature of the maternal genetic information stored in the egg, we have prepared cDNAs from the mRNAs in the fertilized eggs of the ascidian, Halocynthia roretzi. The cDNAs of the ascidian embryo were sequenced, and the localization of individual mRNA was examined in staged embryos by whole-mount in situ hybridization. The data obtained were stored in the database MAGEST (http://www.genome.ad.jp/magest) and further analyzed. A total of 4240 cDNA clones were found to represent 2221 gene transcripts, including at least 934 different protein-coding sequences. The mRNA population of the egg consisted of a low prevalence, high complexity sequence set. The majority of the clones were of the rare sequence class, and of these, 42% of the clones showed significant matches with known peptides, mainly consisting of proteins with housekeeping functions such as metabolism and cell division. In addition, we found cDNAs encoding components involved in different signal transduction pathways and cDNAs encoding nucleotide-binding proteins. Large-scale analyses of the distribution of the RNA corresponding to each cDNA in the eight-cell, 110-cell and early tailbud embryos were simultaneously carried out. These analyses revealed that a small fraction of the maternal RNAs were localized in the eight-cell embryo, and that 7.9% of the clones were exclusively maternal, while 40.6% of the maternal clones showed expression in the later stages. This study provides global insights about the genes expressed during early development.

[Plication of the sinotubular junction for aneurysm of the ascending aorta associated with aortic regurgitation: a case report]

A 63-year-old woman with aneurysm of the ascending aorta associated with AR due to dilatation of the sinotubular junction (STJ) and with poor LV function, who did not have Marfan syndrome, underwent a plication of the STJ and replacement of the ascending aorta. In operation, we simultaneously performed the plication of dilated STJ (60 mm) and the replacement of ascending aorta using a 26 mm Woven Dacron graft. Post-operative angiogram (1 POM) showed no aortic regurgitation and good recovery of the LV function. This procedure is less invasive, and indicated for patients without significant elongation or thickening of the aortic valve, especially when the patients have higher risk.

[Light-wand (Trachlight) guided nasotracheal intubation]

We report that Trachlight-guided nasotracheal intubation might be achieved successfully and traumatically without removal of a stiff internal stylet. Endotracheal tube was mounted on a Trachlight with the stylet in position and bent to form a less sharp curvature than a right angle, namely 40-60 degree, at 7 cm proximal to the endotracheal tube tip. Forty-six patients scheduled for nasal intubation were studied to measure the intubation time and the success rate with the use of Trachlight. The tracheas were successfully intubated in 89% of patients. We suggest that Trachlight-guided nasotracheal intubation could be clinically feasible without traumatic complication when applied with a stiff stylet in position and this approach is a useful method for nasal intubation.

[Vestibular symptoms and ENG findings during periods of convalescence after endolymphatic sac drainage and steroid-instillation surgery (EDSS)]

Understanding the appearance of vestibular symptoms during periods of convalescence after surgery for the treatment of Meniere's disease is important for determining when a patient can return to work as well as the long-term results of the operation. We have treated 20 cases of intractable Meniere's disease with endolymphatic sac drainage & steroid-instillation surgery (EDSS) [Kitahara T, et al., Ann Otol Rhlnol Laryngol in press, 2000] and observed the subjective symptoms and objective vestibular findings using electronystagmogram (ENG) during the subsequent period of convalescence. The average postoperative durations of subjective static and evoked vestibular symptoms were 1.7 and 6.7 days, respectively. Those of spontaneous, positional and positioning nystagmus observed using ENG were 1.2, 2.0 and 7.9 days, respectively. In cases with a long history of Meniere's disease, postoperative static vestibular sensation and positional nystagmus lasted significantly longer than in cases with short histories. In cases with poorly developed temporal bony pneumatization in the area behind the posterior semicircular canal, postoperative evoked vestibular sensations and positioning nystagmus lasted significantly longer than in cases with well developed temporal bony pneumatization. Vestibular symptoms resulting from direct invasion during EDSS were considered to be slighter than those resulting from vestibular neurectomy or gentamicin treatment and almost the same as those resulting from endolymphatic sac surgery.

Comparison of sperm motility test methods (except computer-assisted sperm analysis) in rats under the condition of alfa-chlorohydrin treatment--collaborative investigation

A comparison among rat sperm motility test methods including percent of motile sperm (% Motile), scoring method (Scoring), Ishii's method, Progressive Motility Test (PMT) and Sperm Quality Analyzer (SQA), was conducted using data gathered from eleven laboratories. As a unified study design, mature male rats were orally treated daily for approximately 1 week with alpha-chlorohydrin (ACH), which is known to affect the sperm motility at the epididymis, at dose levels of 2.5, 5 and 10 mg/kg, and then subjected to more than two test methods for sperm motility in each laboratory. Scoring (4 or 5 grades), Ishii's method, PMT and SQA showed high sensitivity for the detection of the effects of ACH, which were not considered to be inferior to a computer-assisted sperm analyzer (CASA). Longer incubation time before testing was considered to contribute to detecting the effects of ACH. In particular, we realized that Scoring was a favorable method even if the demerit of poor objectivity was allowed for. Percent Motile showed lower sensitivity than other test methods. The differences in sensitivity between % Motile and other methods were considered to be based on whether the defects of progressive motion could be detected. Although % Motile cannot clearly judge whether immotile sperm are dead or alive, the value is a great help for the interpretation of the result from other methods. Based on the characters for detectability, objectivity and efficiency, the most suitable method of sperm motility should be selected according to the purpose of the toxicity study.

Plasma endothelin and LH-RH, LH, FSH, prolactin, progesterone, 17alpha-hydroxyprogesterone, estrone, 17beta-estradiol, delta4-androstenedione, testosterone, active renin, angiotensin-II and ANP levels in blood and LH, estrone and 17beta-estradiol and pregnanediol levels in urine of normal cycling women

In order to investigate the endothelin (ET) levels and their relationship to various hormones during the menstrual cycle, we measured endothelin-1, -2 and -3 (ET-1, -2 and -3), big ET-1 and big ET-3 levels in 27 normally cycling women (mean age 27 years). Simultaneous determination of luteinizing hormone-releasing hormone (LH-RH), luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin, progesterone, 17alpha-hydroxyprogesterone (17-OHP), estrone, 17beta-estradiol, delta4-androstenedione, testosterone, active renin, angiotensin-II (A-II) and atrial natriuretic peptide (ANP) in blood, and LH, estrone and 17beta-estradiol and pregnanediol levels in urine was made in the same 27 women. The levels of ET-2 in plasma were found to be 20% of those of ET-1. In addition, ET-1 levels were measured in the endometrium of the normal uterus. Plasma ET-1 and ET-3 levels fluctuated during the menstrual cycle, with a peak at the luteal phase, but showed only a negative relationship (p < 0.01) to each other at the menstrual phase, whereas big ET-1 and big ET-3 levels showed no significant changes. Plasma ET-1 and ET-3 levels showed no significant relationship to the big ETs. As for the relationship to other hormones, plasma ET-3 had a negative relationship (p < 0.01) to prolactin and a positive correlation (p < 0.01) with ANP during the entire menstrual cycle. Plasma ET-1 and ET-3 showed a partial positive or negative correlation to LH, FSH, prolactin and ANP levels, depending upon the cycle phase, whereas plasma ETs and big ETs were unrelated to other hormones in the blood, and LH, estrone, 17beta-estradiol and pregnanediol in the urine throughout the menstrual cycle. At each menstrual stage, plasma ET-3 levels were more significantly related to LH, FSH, prolactin and ANP than ET-1, indicating a closer relationship between ET-3 and these circulating hormones during the menstrual cycle. The ET-1 level showed no significant change in the endometrium during the menstrual cycle.

Patency after revision surgery for failing infrainguinal vein grafts

BACKGROUND

Although the results of bypass surgery on arteries in the lower extremities have been greatly improved during the last decades, there are still a significant number of primary failures. In order to investigate the reasons for the failure of autogenous vein grafts after infrainguinal arterial bypass surgery and to ascertain the results of revision operations on the failing grafts, we conducted a clinical study.

METHODS

Retrospective study on 104 patients who underwent infrainguinal arterial revascularisation with autogenous veins.

RESULTS

One hundred and twenty-six bypasses were constructed in 121 limbs. Seventy-nine of these were for claudication and 47 for threatened limbs (rest pain or ischaemic tissue loss). Five-year primary and secondary patency rates were 69.7% and 84.9% respectively. Spliced or suture-repaired grafts had a poor outcome; five out of seven eventually becoming thrombosed. On the other hand, revision operations for failing but not yet thrombosed grafts produced good results; the five-year primary patency rate after these operations was 76.0%, whereas after single-segment primary grafting it was 72.1%.

CONCLUSIONS

These results stress the importance of vigilant follow-up and active intervention for failing grafts. Poor outcome with injured vein grafts emphasizes the importance of meticulous vein harvesting.

[Equilibration period for PaO2 following alteration of FIO2 in mechanically ventilated patients]

To determine arterial oxygen tension (PaO2) in mechanically ventilated patients, we repeatedly measured arterial blood gas (ABG) to examine changes in PaO2 until equilibration following alteration of fractional concentrations of oxygen in inspired gas (FIO2). Forty anesthetized patients with normal arterial oxygenation were randomly assigned to one of four groups. Group 1 (n = 10): Arterial blood samples were drawn every one minute during a 15-min period of equilibration after change of FIO2 from 1.0 to 0.21. Then FIO2 was returned to 1.0 and the similar sampling was repeated. Group 2 (n = 10): The protocol was same as in Group 1 except for FIO2 targeted for 0.8 and 0.4. Group 3 (n = 10): Blood sampling was every two minutes during a 14-min period and repeated while FIO2 was altered as in Group 1. Group 4 (n = 10): The protocol was same as in Group 3 except for the target FIO2 similar to Group 2. PaO2 was stabilized in 4 min at earliest and in 6 min at latest after change of FIO2 in every settings of this study. In mechanically ventilated patients with normal arterial oxygenation, PaO2 could be stabilized after a 6-min period of equilibration following alteration of FIO2.

A case of Currarino triad with familial sacral bony deformities

We describe a male patient presenting with Currarino triad: a recto-urethral fistula, sacral bony deformity, and a presacral teratoma. Clinical screening of his family revealed three additional cases with incomplete forms of this association. Cytogenetic findings in the patient and his mother were normal. This case suggests that the occurrence of an anorectal malformation together with a sacral bony deformity should raise a physician's index of suspicion for associated presacral tumors, and that screening of the patient's family members with sacral radiographs is necessary.

[Management of the acoustic tumor in an only/better hearing ear]

Because profound bilateral hearing impairment is a catastrophic event, the management and care of an individual with an 8th nerve lesion in an only/better hearing ear remains a significant challenge for both patient and physician. Current options regarding the treatment of the acoustic tumor in an only/better hearing ear include: observation, attempted hearing preservation surgery and stereotactically guided radiation therapy. In this article, we present 3 cases of acoustic tumor within the internal auditory canal in an only/better hearing ear diagnosed by gadolinium-enhanced MRI and discuss the recommendations, especially observation, available in the care of these cases. In one patient, hearing disturbance caused by the tumor in a better hearing ear made the patient quite depressive and desperate. One of the most important consideration is for the physician to provide the patient with adequate informed consent regarding the possibility of profound bilateral hearing loss caused by either the natural growth or surgical removal of the tumor in the future, and alternative methods of communication with others such as: hearing aid and lip reading, cochlear implant and brainstem implant.

[Anesthetic management for a patient with spondyloepiphyseal dysplasia congenita]

An 11-year-old girl with spondyloepiphyseal dysplasia congenita in the spine was scheduled for virectomy under general anesthesia. She had slight scoliosis in the thoracic and lumbar spine, moderate funnel chest and slight thoracic kyphosis. Preoperative laboratory data were within normal range and her intelligence was normal. Her Mallanpathi's score, however, was Grade 3 and effective mandibular length/posterior depth of mandible ratio was 3.48 on the lateral view of head X-ray. From these data, difficult intubation was expected. Although anesthesia was induced uneventfully using thiamylal and vecuronium, her vocal cord was not visualized under laryngoscope. Using cricoid pressure procedure, slightly left-shifted vocal cord was exposed. However a 26 Fr. size endotracheal tube without cuff was too large and finally a 22 Fr. tube was inserted. During the operation patient's general condition was stable and the operation was finished without any episodes. She did not have any complications in the postoperative period. In a case of SDC, pathological changes in laryngotracheal resion should be examined and evaluated preoperatively and difficult intubation should also be always taken into account.

Identification of a novel polymorphism of the human dopamine transporter (DAT1) gene and the significant association with alcoholism

Human dopamine transporter gene (DAT1) has a variable number of tandem repeats (VNTR) in its 3'-untranslated region (UTR). The association between the VNTR polymorphism and neuropsychiatric disorders has been studied, but their relationship is still unclear. Here we identified a novel polymorphism in the 3'-UTR of the DAT1 gene, G2319A, and a significant association between the polymorphism and alcoholism was observed in both genotypic and allelic frequencies (P = 0.040 and 0.019, extended Fisher's exact test, respectively). There was a significant gene dose effect on the risk for alcoholism associated with the 2319-A allele (chi2 = 6.16, df = 2, P = 0.046, linearity tendency test: Cochranq-Armitage analysis). Moreover, in the haplotype analysis with G2319A- and VNTR-polymorphisms, a positive gene dose efffect on the risk with the A10 allele (P = 0.044, linearity tendency test) and a negative gene dose effect with the G10 allele (P = 0.010, linearity tendency test) for alcoholism were significantly detected. Odds ratio for alcoholism with the A10 and G10 alleles were 1.76 (1.12-2.76) and 0.53 (0.32-0.79), respectively. These results indicate that the DAT1 gene may confer vulnerability to alcoholism.

Inhibitory effect of methylene blue-induced photooxidation on intimal thickening of vein graft

BACKGROUND

We have previously speculated that methylene blue-induced photooxidation of adventitial surface for 5 minutes can completely inhibit the intimal and medial growth of surgically prepared saphenous vein in vitro. In this study, inhibitory effect of methylene blue-induced photooxidation on intimal thickening of vein graft in vivo was investigated.

METHODS

Jugular vein grafts were photooxidized in 0.01% methylene blue solution for 5 minutes, and interposed into arterial circulation for 4 weeks in rabbits. Vein grafts were studied by morphometry and immunohistochemistry.

RESULTS

The intimal thickening of photooxidized vein grafts were suppressed significantly compared with those in the nonphotooxidized group. Proliferated cell nuclear antigen (PCNA) index (total PCNA-positive cells/total cell count x 100%) of vein graft was significantly higher in the nonphotooxidized group than those in the photooxidized group.

CONCLUSIONS

Methylene blue-induced photooxidation is effective in the inhibition of intimal thickening of vein graft interposed in the arterial circulation for 4 weeks in vivo.

[A case of advanced retroperitoneal dedifferentiated liposarcoma treated effectively with high-dose ifosfamide]

We report a case of retroperitoneal dedifferentiated liposarcoma treated effectively with high-dose ifosfamide. A 59-year-old man received tumorectomy and right nephrectomy for the retroperitoneal liposarcoma. Twenty-two months after the operation, the liver metastasis was resected incompletely. Three months later, right pleural, retroperitoneal and peritoneal metastases appeared. With 6 cycles of high-dose ifosfamide therapy these tumors were reduced partially. Ten cycles of this chemotherapy were administered. These tumors showed regrowth at 14 months after administration of high dose ifosfamide. The combination chemotherapy of ifosfamide and doxorubicine or etoposide was not effective after regrowth of the tumors.

Intrapericardial organized hematoma. A rare complication after open heart surgery

Intrapericardial organized hematoma, which compresses cardiac chambers late after open heart surgery, is extremely rare. We report a case of intrapericardial organized hematoma in a 63-year-old man who underwent aortic valve replacement 8 years prior, which may have aggravated rheumatic mitral valve regurgitation compressing the mitral valve anulus. Under extracardiopulmonary bypass and cardioplegic heart arrest, we removed the hematoma and replaced the mitral valve with a 27 mm St. Jude Medical valve. There were no bleeding points on the heart and pericardium at operation and no history of blunt chest trauma. The etiology of the hematoma is uncertain.

Conformational and amino acid residue requirements for the saposin C neuritogenic effect

Prosaposin is the precursor of four activator proteins, termed saposins A, B, C, and D, that are required for much of glycosphingolipid hydrolysis. The intact precursor also has neurite outgrowth activity ex vivo and in vivo that is localized to amino acid residues 22-31 of saposin C. Across species, this saposin C region has a high degree of identity and similarity with amino acids in the analogous region of saposin A. Wild-type and mutant saposins C and A from human and mouse were expressed in E. coli. Pure proteins, synthetic peptide analogues, conformation-specific antibodies, and CD spectroscopy were used to evaluate the basis of the ex vivo neuritogenic effect. Wild-type saposin A had no neuritogenic activity whereas reduced and alkylated saposin A did. Introduction of the conserved saposin A Tyr 30 (Y30) into saposin C at the analogous position 31, a conserved Ala(A)/Gly(G)31, diminished neuritogenic activity by 50-60%. Nondenatured saposin A with an introduced A30 acquired substantial neuritogenic activity. Polyclonal antibodies directed against the NH2-terminus of saposin C cross-reacted well with reduced and alkylated saposins C and A, wild-type saposin C, and saposin A [Y30A], poorly with saposin C [A31Y], and not at all with wild-type saposin A. CD spectra of wild-type and mutant saposins C and A, the corresponding neuritogenic region of saposin C, and the analogous region of saposin A showed that more "saposin C-like" molecules had neuritogenic properties. Those with more "saposin A-like" spectra did not. These studies show that the neuritogenic activity of saposin C requires specific placement of amino acids, and that Y30 of saposin A significantly alters local conformation in this critical region and suppresses neuritogenic activity.

Descending branch of lateral femoral circumflex artery as a new alternative free graft in re-do CABG

To re-do coronary artery bypass grafting (CABG), we employed the descending branch of the lateral femoral circumflex artery (LFCA) as a free arterial graft. Early postoperative angiography demonstrated that the graft was patent with a sufficient flow. The descending branch of the LFCA can be recommended as a possible arterial graft for re-do CABG.

Effect of primers on bonding agent polymerization

The aim of the present study was to evaluate the effect of primers on the polymerization of bonding agent. We measured the degree of conversion (radical production) and mechanical properties (surface hardness and direct tensile strength) of various adhesives/primers mixed at different ratios and the effect of varying the visible-light curing time. With and without primer treatment, the tensile bond strength of adhesive resin to micacious glass ceramic and human enamel was measured. After the tensile bond test, using the Image Capture System, the failure patterns of adhesive resin bonded to micacious glass-ceramic were analysed. The results show that the mixtures containing the higher amounts of primer yielded a lower degree of conversion and inferior mechanical properties when compared with the mixtures containing a lower proportion of primer, except in the experimental bonding system. The adhesive/primer mixtures inhibited free radical polymerization. The value for the Knoop hardness number and the direct tensile strength of the adhesive/primer mixtures were significantly decreased compared with those of the adhesive bonding agent alone with no primer added. The tensile bond strength of adhesive resin bonded to micacious glass-ceramic or human enamel without primer treatment was significantly greater than that of adhesive resin with primer treatment in certain cases. Most of the fractures of ceramic surfaces were cohesive (within resins) and/or interface (at the ceramic surface) failure.

[A case of infective thoracic aortic aneurysm ruptured to the lung]

We report a successful surgical treatment of an infective thoracic aortic aneurysm ruptured to the left lung. A 63-year-old man who had been suffering from fever and cough showed twice of hemoptysis. Chest CT revealed a descending thoracic aortic aneurysm ruptured to the left lung. A semiemergent operation was performed. At operation, aneurysm of descending thoracic aorta was found adherent to the left lung. Aneurysmectomy with left pneumonectomy was carried out. The postoperative course of the patient was uneventful. Conceivably, in order to avoid massive intraoperative bleeding during division of dense adhesion and postoperative graft infection, concomitant lung resection is necessary.

In vitro and in vivo calcification of vascular bioprostheses

Efficacy of different chemical treatments on calcification of vascular graft in vitro and in vivo was studied. Culture medium-filled rat aortas were separately treated in 0.2% glutaraldehyde and epoxy compound, and photooxidized in 0.01% methylene blue for a shorter period (group 1). Another group of rat aortas were separately treated in the same chemicals for a longer period (group 2). All fresh and treated aortas of both groups were cultured for 21 days in an organ culture medium and implanted (except for group 1) in weanling rats for five months. Histology and immunohistochemistry revealed that differently treated aortas of group 1 grow and calcify, and the smooth muscle cells between elastin fibers are the primary site of calcium deposition. In contrast, differently treated aortas of group 2 neither grew, nor did calcify in the medium except the epoxy compound cross-linked aorta of group 2 which did not grow but did calcify. Untreated aorta did not calcify. All fresh and differently treated aortic homografts calcified severely in rats. Our whole arterial segment-calcification system would be useful for analyzing the molecular and cellular mechanisms of both bioprosthetic and atherosclerotic calcification of vascular graft. New anticalcification technique is the only hope for better outcome of future vascular bioprostheses.

Successful treatment of aortoesophageal fistula resulting from aneurysm of the aortic arch

Aortoesophageal fistulas from primary thoracic aortic aneurysms are almost always fatal. In the English literature we have found only four successfully managed cases, all descending thoracic aortic aneurysms. We report an elderly woman who developed an aortoesophageal fistula from an aortic arch aneurysm. She was successfully managed with graft replacement including reattachment of arch vessels and a staged esophagectomy which was accompanied by mobilization of the omentum into the space between the esophagus and the prosthetic graft. She was the first successfully treated patient with aortoesophageal fistula resulting from aortic arch aneurysm.

Surgical treatment of the coronary artery to pulmonary artery fistulas in adults

Coronary artery to pulmonary artery fistula (CA-PAF) is a rare congenital anomaly. The purpose of this retrospective study was to analyze 11 adult patients with CA-PAFs treated surgically, and to evaluate the surgical management and long-term results. There were no surgical deaths and all patients survived the follow-up periods (mean 7.2 years). All symptomatic patients improved their New York Heart Association functional class. As surgical correction is safe and effective, with good long-term results, all the patients with CA-PAF in adults can be candidates for surgery to prevent life-threatening complications.

Transiliac vein approach to a permanent pacemaker implantation after aortic valve reoperation

This article describes the case of a 71-year-old woman in whom a permanent pacemaker implantation was performed through an iliac vein because of superior vena cava obstruction after aortic valve reoperation. During a 6-month follow-up, the patient did well and the pacemaker performance was satisfactory.

[Inhibitory effect of macrolide antibiotics on biofilm formation by Pseudomonas aeruginosa]

In recent years, various medical indwelling devices have been developed and used. Bacteria adhering to these devices often cause refractory infection. In the field of otolaryngology, refractory infection accompanying these medical indwelling devices such as middle ear ventilation tubes and artificial auditory ossicles has been reported. The concept of bacterial biofilm infection has been suggested as an explanation for the refractory infection. Furthermore it has been reported that a bacterial biofilm is involved in refractory infection unrelated to medical indwelling devices. Topical biofilm formation was detected in patients with chronic sinusitis, chronic purulent otitis media or habitual tonsillitis. In this study, we morphologically and quantitatively examined the biofilm-forming capacity of a clinically isolated strain of mucoid type Psecudomonas aeruginosa on Teflon to investigate the effects of macrolide antibiotics on bacterial biofilm formation. In the morphological examination, P.aeruginosa was cultured together with a Teflon sheet in minimal medium containing various concentrations of the macrolide antibiotics clarithromycin (CAM), erythromycin (EM) and midecamycin (MDM), at 37 degrees C for 7 days. The surfaces of the Teflon sheets were examined by electron microscopy. The adherent bacteria and biofilm formation on Teflon sheets soaked in minimal medium containing CAM or EM were found to be decreased in a dose-dependent manner. However, in the Teflon sheets soaked in minimal medium containing MDM, there was no decrease in biofilm formation regardless of the MDM concentration. In the quantitative examination, P. aeruginosa was cultured in minimal medium containing various concentrations of the macrolide antibiotics at 37 degrees C for 7 days together with Teflon beads. The levels of hexose, protein and alginate adhering to the Telfon beads were quantified as an estimation of biofilm formation. On Teflon beads treated with CAM or EM, there were dose-dependent decreases in hexose, protein and alginate levels. In particular, marked decreases were noted when CAM and EM concentrations were 10 micrograms/ml or more. Furthermore, there was no significant difference between CAM and EM. However, in the presence of MDM, there was no decrease in hexose, protein or alginate levels regardless of the MDM concentration. The minimal inhibitory concentration (MIC100) of each macrolide against P. aeruginosa used in this experiment was 100 micrograms/ml or more. There may be no bactericidal effect on this strain at the macrolide concentrations used in this experiment. However, this experiment used 7-day treatment. The long-term bactericidal activity of macrolides was examined. In the presence of CAM or MDM, bacterial levels after culture were similar to preculture levels or slightly lower than the preculture levels. In the presence of EM, bacterial levels were similar to the preculture levels. These results demonstrated that CAM and EM, which are 14-membered macrolides inhibited biofilm formation, while MDM which is 16-membered macrolide, did not. These inhibitory effects of CAM and EM may be related to actions other than bactericidal activity. In our experiment, CAM and EM inhibited biofilm formation at 10 micrograms/ml or more. This concentration corresponded to 1/20 x MIC. This concentration can be achieved in tissues, nasal discharge and sputum with actual clinical doses. Therefore, these agents may be effective against biofilm disease caused by P. aeruginosa in the field of otolaryngology.

[A case of pedunculated intrathoracic chest wall type lipoma]

The case was a 52-year-old female. Though the abnormal shadow on the chest X ray film was pointed out in 1990, she had been observed as a benign intrathoracic tumor for one year and four months. But she was admitted to our hospital for further evaluation because the mass shadow enlarged subsequently. The mass shadow was suspected as intrathoracic lipoma by the CT and MRI. However, because the shadow enlarged and its inner part was not single density that was equal to subcutaneous adipose tissues, left thoracotomy was performed. The tumor was pedunculated from the fatty tissue of the fifth intercostal space near the tubercle of rib. It was easily resectable, encapsulated and measured 6.0 x 3.5 x 2.5 cm in size. It was histologically diagnosed as benign lipoma. Preoperative diagnosis of the present tumor became possible to a certain extent by means of CT and MRI. However, in view of imperfect differentiation between lipoma and liposarcoma, the surgical treatment should be considered.

[Thoracoscopic surgery for benign esophageal diseases]

The thoracoscopic surgery for two benign esophageal diseases, esophageal leiomyoma and esophageal diverticulum, were successfully performed. Case 1 was a 37-year-old female with esophageal leiomyoma that was located at 30 cm from the incisor of the left anterior esophagus. The tumor was enucleated under the thoracoscopy, combined mini-thoracotomy for 3 cm in length. It was useful enough to rotate the left side to the right with two slings traction for better visualization of lesion site. After resection, the proper muscle layer of the esophagus was closed. Case 2 was a 70-year-old male, who complained of dysphagia because of esophageal diverticulum. It was 8 cm in size and located at 28 cm from the incisor of the right wall of the esophagus. It was also resected under the thoracoscopy, combined mini-thoracotomy for 3 cm in length. Intraluminal esophagoscope was useful to dissect safely and confirm the intralumen of the diverticulum. Its neck was divided parallel to the longitudinal axis of the esophagus by two endo-staplers. And then, the muscle layer was closed. It was suggested that esophageal leiomyoma and esophageal diverticulum were suitable for thoracoscopic surgery.

[Permanent pacemaker implantation in patients aged 80 years or older]

Forty-five patients aged 80 years or older at the time of initial permanent pacemaker implantation were followed for 3 to 132 months (mean 40.8). There were 27 males and 18 females. The mean age was 84 years. Acute voltage threshold, lead impedance, R wave amplitude of these patients showed no difference from those of younger patients (< 80 years). Complications occurred in 5 patients as follows: cerebral infarction, 3: perforation, 1; lead displacement, 1. Ten patients died, and main causes of death were decrepitude and cancer. The five-year cumulative survival rate (75.9%) was superior to the expected survival rate (65.8%) by life-table analysis. In conclusion, pacemaker therapy for elderly patients is safe, and seemed to improve their long-term prognosis.

[Readmission among discharged psychiatric patients and it's correlates]

OBJECTIVE

This study investigated the incidence of readmission among discharged psychiatric patients and examined factors predicting early readmission.

METHODS

A cohort of 343 patients, who had been hospitalized involuntarily to mental hospitals for medical care and custody, and who were discharged between April 1991 and September 1993, in two areas served by Fukuoka Prefectural Yamato Health Center (n = 163) and Tagawa Health Center (n = 180) were followed up until November 1994.

RESULTS

The readmission rates within 6 months of discharge in Yamato Health Center and Tagawa Health Center were 17% and 22%, and within 1 year were 30% and 31% respectively. From Cox's proportional hazards model, alcohol/drug abuse, many of previous admission, long length of recent hospitalization, payment of medical care cost from public assistance, complication of physical disorders, living without a person responsible for custody after discharge, no request of health center's service by the hospital and discharge from a large-scale mental hospital were significantly related to increased risk of readmission. Not a few patients could not be followed up completely because of early drop-out of treatment. The drop-out rates within 1 month of discharge in Yamato Health Center and Tagawa Health Center were 10% and 26%, and within 1 year were 15% and 27% respectively.

CONCLUSIONS

The rates of readmission and drop-out of treatment among discharged psychiatric patients were considerably high. This study clarified that rapid establishment of a mental health system supporting the mentally disabled in a community is an urgent need in Japan.

[Graft replacement for repair of coarctation of the aorta in adults: a case report]

A 42-year-old woman admitted to the hospital because of systolic murmur and upper body hypertension. Cardiac catheterization revealed tubular coarctation of the aorta and 60 mmHg pressure gradient across the coarctation. The graft replacement for repair of coarctation of the aorta was performed under femoro-femoral cardiopulmonary bypass. Since about 49% of surgically untreated patients of this disease may be expected to die before 30 years of age, repair of coarctation of the aorta in adults should be performed as soon as possible.

[Primary carcinosarcoma of TE lung--a report of two cases]

Carcinosarcoma is a rare lung tumor and accounts for less than 0.3% of primary lung malignancies. Since the first description by Kika in 1908, only 36 cases with this kind of tumor have been appeared in the Japanese literatures by 1993. This report presents our surgical experiences of two cases with carcinosarcoma of the lung confirmed by pathological examination. Case 1: 64-year-old male underwent left lower lobectomy with lymph node resection. The patient has been well 27 months after the operation without tumor recurrence. Case 2: was a 75-year-old male, who underwent left upper lobectomy, partial resection of left lower lobe (S6) with lymph node resection. This patient died of aspiration pneumonia 90 days after successful resection of the tumor. In both patients, resected lung tumors were diagnosed to be true carcinosarcoma by histopathological examinations. True carcinosarcoma is defined to contain both cancelous and sarcomatous elements. Sarcomatous elements may differentiate into rhabdomyosarcoma, osteosarcoma and so on, or they may have non-epithelial elements demonstrated by electron microscopy or immunohistochemical studies. We reviewed the 36 cases with carcinosarcoma of the lung reported in Japanese literatures with special consideration of their histopathological findings. The prognosis of the patients with this rare tumor is also discussed according to the TMN stages.