[A case report of primary repair for thoracic and thoracoabdominal and iliac artery aneurysms associated with severe visceral artery occlusive diseases--a redo operation for thoracoabdominal aortic aneurysm after infrarenal abdominal aortic aneurysm repair]

Abdominal aortic aneurysms can now be successfully repaired with low mortality and few early complications. On the other hand, the cases that required operations for recurrent aneurysms have been increased during long term follow-up period. In such cases, there are many difficulties for operative procedures compared to their first operations and many risk factors. A case of successful operation for the thoracoabdominal aortic aneurysm associated with severe stenotic lesions of the visceral arteries and descending thoracic aneurysm and left common iliac artery aneurysm are reported. A 74-year-old man who underwent operation for infrarenal abdominal aortic aneurysm and left nephrectomy 7 years and 9 months ago at our institution developed an aneurysm just above the proximal anastomosis with severe stenotic lesions of the visceral arteries. At the same time, descending thoracic aortic aneurysm and left common iliac artery aneurysm were associated. And he had ischemic heart disease. Under selective perfusion of the visceral arteries, graft replacement of these aneurysms and reconstruction of superior mesenteric artery and right renal artery were done. The patient had good post operative course and started oral feeding at 3 post operation day. He returned to his occupation and is doing well with no trouble one and half year after operation.

Operative results of thoracoabdominal repair for chronic type B aortic dissection

From January 1991 to May 1994, we have operated on 15 cases of Type B aortic dissection. In 10 of these patients, thoracoabdominal repair was performed. According to Crawford's classification, 2 patients fell into Type I, 6 patients into Type II, and 2 patients into Type III. The aneurysms were exposed through a left thoracotomy extending into the retroperitoneum with the hemidiaphragm divided circumferentially. The operations were performed under femoro-femoral partial cardiopulmonary bypass. In 6 of these cases selective perfusion of the visceral branches was used. The celiac axis was reconstructed in 10 patients, superior mesenteric artery in 9, right renal artery in 7, left renal artery in 6. Abdominal vessels were reconstructed by the "inclusion" technique described by Crawford in 2 patients, by "beveling" the distal prosthetic end in 6 and by the "interposition" technique in 4 patients. Vessels arising from the false lumen were reconstructed by the "interposition" technique. To prevent paraplegia, the evoked spinal cord potentials by direct stimulation of the cord (ESPs-dsc) were monitored perioperatively and the aneurysms were repaired sequentially in segments. In all patients except 2 with Crawford type III aneurysms, spinal cord ischemia was detected by ESPs-dsc. In 7 of these patients, 2 to 8 pairs of intercostal/lumbar arteries (I/L aa.) that arose from the "responsible" aortic segment were reconstructed. Reconstruction techniques included the "inclusion" technique in 2 patients, the "beveling" technique in 1, the "interposition" technique in 1 and the "on lay grafting" technique in 3 patients. One hospital death occurred in a patient who had chronic renal insufficiency and liver cirrhosis preoperatively. Spinal cord injury occurred in 5 patients, including 4 paraparesis and 1 delayed-onset paraplegia. In 2 of these patients, responsible I/L aa., were not reconstructed correctly despite ESPs changes, and injury might have been prevented if reconstruction of the "responsible" arteries had been performed. Thoracoabdominal repair for chronic Type B aortic dissection could be performed safely with an acceptable mortality rate. Spinal cord injury remains an unsolved problem.

Effects of stimulated free latissimus dorsi muscle graft on LVEDV and LVSW: a new dynamic cardiomyoplasty technique

The effectiveness of dynamic cardiomyoplasty (DCMP) remains controversial. We hypothesized that effectiveness of DCMP using the latissimus dorsi muscle graft (LDMG) depends on the wrapping method. We analyzed pressure-volume relations (PVR), the left ventricular stroke work (LVSW), and the left ventricular end diastolic volume (LVEDV) changes during nonstimulation and stimulation of the LDMG to evaluate the effect of a new wrapping method of DCMP on the LVSW and the LVEDV changes. The new wrapping technique was evaluated in an acute animal experimental model. In 12 mongrel dogs, we performed continuous measurement of the dimensional and pressure dates of the left ventricle (LV) after the DCMP. The measurement was performed 15 min after wrapping during 5 periods. The duration of one measurement period was 15 s. The animals were divided into 2 groups according to the wrapping method. The heart was wrapped with the LDMG using 2 different methods. For Method 1, Carpentier's method, the heart was wrapped primarily with the distal part of the LDMG, the lateral segment. The vasculoneural pedicle of the latissimus dorsi muscle (LDM) was preserved. For Method 2, the LDM was separated, and the vasculoneural pedicle was cut. The medical sternotomy was performed. The thoracodorsal artery of LDMG was anastomosed to the right internal mammary artery, and the thoracodorsal vein was anastomosed to the right atrial appendage. The heart was wrapped primarily with the proximal part of the "free LDMG," the transverse segment. Based on the PVR loops, the changes of the LVSW and the LVEDV in both experimental groups were analyzed. The paired t-test was used for statistical analysis. Using Method 1, the LVSW and the LVEDV showed no significant changes during stimulation (stim) of the LDMG, compared with nonstimulation (nonstim) (LVSW: nonstim, 970 +/- 168 erg x 10(3); stim, 1,181 +/- 203 erg x 10(3); p = 0.126 and LVEDV: nonstim, 36.6 +/- 6.7 ml; stim, 37.2 +/- 6.8 ml; p = 0.36). Using Method 2, the LVSW was increased, and the LVEDV was decreased during stimulation of the free LDMG, compared with nonstimulation (LVSW: nonstim, 694 +/- 117 erg x 10(3); stim, 846 +/- 104 erg x 10(3); p < 0.001 and LVEDV: nonstim, 47.7 +/- 2.8 ml; stim, 46.8 +/- 2.7 ml; p < 0.001). The stimulated free LDMG wrapping of the heart seems to be a more effective wrapping method for DCMP, and it results in an increase of the LVSW and a decrease of the LVEDV, compared with the original Carpentier's method.

[Regulation of growth and survival of germ cells]

Growth and survival of germ cells seem to be strictly regulated by a number of environmental and intrinsic factors. One of the most important factor is Steel factor, which is necessary not only for the rapid proliferation and survival of primordial germ cells(PGCs) in embryos, but also for the development of spermatogonia and oocytes in adult gonads. Other growth factors which are linked to different signaling pathway collaboratively support PGC growth with Stecl factor. Therefore, synergistic action of different signal transduction pathway seems to be important for PGC growth. In adult testis, a large part of spermatogonia undergoes cell death, but the physiological significance and molecular mechanisms of this process are largely unknown. We have investigated the effect of misexpressing Bcl-2 in spermatogonia in transgenic mice. And we found that ectopically expressed Bcl-2 in spermatogonia inhibited their normal apoptosis. In addition abnormally accumulated spermatogonia fail to undergo further differentiation and survival, and they were just deleted from testis. These results indicate that spermatogonial apoptosis is part of the normal program of mammalian spermatogenesis and is regulated by a pathway affected by Bcl-2.

Effects of glycyrrhizin on immune-mediated cytotoxicity

Intravenous administration of glycyrrhizin is known to decrease elevated plasma transaminase levels in patients with chronic viral hepatitis, in which immune-mediated cytotoxicity by cytotoxic T lymphocytes and tumour necrosis factor (TNF)-alpha is considered to play an important pathogenic role. However, the immunological interpretation of the transaminase-lowering action of glycyrrhizin is not known. Studies were performed to elucidate this action immunologically by assessing the effects of glycyrrhizin on immune-mediated cytotoxicity using an antigen-specific murine CD4+ T hybridoma line, which exhibits cytotoxicity against antigen-presenting cells after stimulation with specific antigen, and a murine TNF-alpha-sensitive fibroblast line. Glycyrrhizin inhibited the cytotoxic activity of the T cells against antigen-presenting cells and also suppressed TNF-alpha-induced cytotoxicity in the TNF-alpha-sensitive cell line in vitro. These results suggest that the decrease of elevated transaminase levels by glycyrrhizin in patients with chronic viral hepatitis is mediated in part by inhibition of immune-mediated cytotoxicity against hepatocytes.

Preoperative determination of the surgical procedure for hepatectomy using technetium-99m-galactosyl human serum albumin (99mTc-GSA) liver scintigraphy

Technetium-99m-diethylenetriaminepentaacetic acidgalactosyl human serum albumin (Tc-GSA) is a new liver scintigraphy agent which binds to the asialoglycoprotein receptors. We evaluated the preoperative assessment for hepatectomy using Tc-GSA liver scintigraphy. Ninety patients with hepatocellular carcinoma were admitted for elective hepatectomy. Tc-GSA scintigraphy was conducted after the intravenous injection of Tc-GSA, and maximal removal rate of Tc-GSA (GSA-Rmax) was calculated using a radiopharmacokinetic model. Measurement of GSA-Rmax, conventional liver function, and 15-minute retention rate of indocyanine green (ICGR15) was carried out preoperatively. The relationships between liver functions, histological activity index (HAI), ICGR15, and GSA-Rmax values were estimated. A significant correlation was obtained between GSA-Rmax and ICGR15 (r = .534, P < .0001). Preoperative discrepancies between GSA-Rmax and ICGR15 values were seen in 15 patients. In these cases, the GSA-Rmax values correlated well with the total HAI scores (r = .595, P < .02), but no significant correlation was seen between the ICGR15 and HAI scores. Two patients died of postoperative liver failure within 2 months of the operation. These two patients were found to have severe discrepancies between their preoperative GSA-Rmax and ICGR15 values. We concluded that GSA-Rmax might be useful for selecting candidates for hepatectomy and that extended hepatectomies (di- and tri-segmentectomy) are high-risk surgical procedures in the case of low GSA-Rmax scores (below 0.35).

Vascular involvement in cutaneous sarcoidosis

Sarcoidosis is a systemic granulomatous disease with systemic vascular involvement, that is, granulomatous angiitis and microangiopathy. To determine if there is vascular involvement in cutaneous sarcoidosis, we examined 42 skin specimens taken from 32 patients with cutaneous lesions of sarcoidosis. Cutaneous sarcoidosis was prevalent in older females with high serum angiotensin-converting enzyme (ACE) levels. Most skin lesions appeared during the following-up of sarcoidosis. Granulomatous angiitis was present in 12 specimens of sarcoid skin lesions (30.8%). Eight of the 12 specimens showed venous involvement in the dermis. There was no correlation between the incidence of granulomatous angiitis and the gross pattern of cutaneous sarcoidosis. Immunohistochemically, thrombomodulin was negative in the vascular endothelium close to the granuloma or a periphlebitis lesion. Electron microscopy revealed endothelial swelling, luminal narrowing, and basal lamina layering of the basement membrane in the capillaries and venules in the dermis. These findings demonstrated that granulomatous angiitis and microangiopathy coexist in cutaneous sarcoidosis.

Extensive replacement of the aorta from the ascending aorta to the supraceliac abdominal aorta during a one-stage operation

A successful replacement of the aorta from the ascending aorta to the supraceliac abdominal aorta in one operation is herein reported. The patient was 66-year-old woman who had DeBakey type I chronic aortic dissection with a pre-disseminated intravascular coagulation (DIC) condition. The image diagnosis revealed a markedly enlarged false lumen with a narrow true lumen in the ascending aorta extending to the diaphragm level while below the diaphragm level, the aortic dilatation was mild. The operation was performed through both a thoracoabdominal incision and a median sternotomy to expose the whole thoracic aorta, and the aorta was replaced from the ascending aorta to the supraceliac abdominal aorta. Selective cerebral perfusion was used for cerebral protection and this was a useful adjunct since no time limitations were thus required during repair of the aortic arch. Although the patient developed several complications postoperatively, she eventually recovered and was discharged from the hospital without any neurological disorders.

A receptor tyrosine kinase, Sky, and its ligand Gas 6 are expressed in gonads and support primordial germ cell growth or survival in culture

Although a number of growth factors and their receptors are involved in the proliferation and differentiation of primordial germ cells (PGCs), the only factor that has been shown to be active in vivo is Steel factor, a ligand for c-Kit. To identify new growth factor receptors that may be required for PGCs function in vivo, we used an reverse transcription-polymerase chain reaction-based strategy to screen for protein kinase genes expressed in PGC-derived embryonic germ cells. We report here that one such gene encoding the receptor tyrosine kinase, Sky, is expressed in both PGCs and their supporting cells in male genital ridges after 11.5 dpc. Interestingly, Sky expression was not detected in female genital ridges, although transcripts were detected in supporting cells in the developing ovary at later stages. Gas 6, a ligand for Sky, was also expressed in interstitial cells which surround Sky positive cells in genital ridges, and, in addition, it supported PGC growth or survival in culture. After birth, Sky expression in testis was restricted to Sertoli cells, and Gas 6 was detected around peritubular cells and Leydig cells. These results suggest that Gas 6-Sky signaling plays a role in PGC growth, sexual differentiation, and Sertoli cell functions in vivo. Sky expression in Sertoli cells diminished by 3 weeks of age, when haploid germ cells first appear. On the other hand, the expression in Sertoli cells was markedly upregulated in the testis of germ cell-deficient W/Wv and jsd/jsd mice. The results suggest that signals from differentiated germ cells suppress Sky gene expression in Sertoli cells. High-resolution chromosomal mapping of Sky is also reported.

Detection of antibodies to Borrelia species among patients with confirmed sarcoidosis in a region where Lyme disease is nonendemic

BACKGROUND

Lyme disease is a multisystemic disorder caused by the spirochete Borrelia burgdorferi, while sarcoidosis is a multisystemic granulomatous disease of unknown etiology. The purpose of this study was to evaluate the relationship between Lyme disease and sarcoidosis.

METHODS

We examined the seroprevalence of antibody to Borellia species in patients with sarcoidosis. We performed the enzyme-linked immunosorbent assay, using three Japanese Borrelia species in addition to B. burgdorferi, and dotblot analysis using purified Borrelia-specific proteins in 38 patients with histopathologically confirmed sarcoidosis and 80 healthy controls.

RESULTS

Two patients (5.3%) were positive for antibodies to Borrelia species according to one or both assays, and one (1.2%) healthy control was positive. In both patients it was suspected that Borrelia infection had developed prior to the development of sarcoidosis.

CONCLUSION

Borrelia species were thought not to be responsible for the development of sarcoidosis in a nonendemic region in Japan. Since clinical manifestations of Lyme disease share certain similarities with those seen in sarcoidosis, ophthalmologists should be aware of the need to differentiate between the two diseases and the need for prompt treatment in each case.

Somatosensory afferent inputs release 5-HT and NA from the spinal cord

Endogenous serotonin (5-HT) and noradrenaline (NA) release by somatosensory afferent inputs was investigated at the level of the spinal cord using in vivo microdialysis technique combined with high performance liquid chromatography and electrochemical detection (HPLC-ECD). Selective stimulation of large myelinated A beta afferent fibers significantly increased 5-HT release to 151.1 +/- 10.1% of the control, but did not affect NA release. However, selective stimulation of small myelinated A delta fibers released NA rather than 5-HT. The NA level enhanced to 128.8 +/- 6.4% of the control after A delta fibers were stimulated with the intensity of 6 times threshold. Stimulation of unmyelinated C fibers unavoidably excited the A beta and A delta afferent fibers, causing both 5-HT and NA release from the spinal cord. The results suggest that both innocuous and noxious information may activate serotonergic descending pathways. The noradrenergic descending pathways are only triggered by noxious inputs transmitted by small afferent fibers.

A novel serine/threonine kinase gene, Gek1, is expressed in meiotic testicular germ cells and primordial germ cells

We have isolated a novel serine/ threonine kinase gene designated Gek1 from mouse primordial germ cell-derived embryonic germ cell. Gek1 is preferentially expressed in meiotic testicular germ cells and primordial germ cells. Gek1 mRNA is also detected in several other tissues, including hematopoietic organs in adult mice and central nervous system in embryos. The Gek1 cDNA encodes a protein with the consensus sequence of the catalytic domain of protein kinases in its N-terminal region. The deduced amino acid sequence of Gek1 in the kinase domain is related to those encoded by the Saccharomyces cerevisiae STE20, CDC15, and Drosophila melanogaster ninaC. The patterns of expression and the structural features of Gek1 suggest that the gene product is involved in signal transduction or nuclear division of germ cells and other proliferating cells. We also show that Gek1 locates on chromosome 11, near the wr locus, showing neuronal and reproductive defects.

[Subtotal aortic replacement in a patient with Marfan's syndrome--replacement of the ascending aorta and entire aortic arch for acute type I aortic dissection 4 years after the thoracoabdominal replacement]

We report a patient with Marfan's syndrome who underwent replacement of the ascending aorta and the entire aortic arch for acute type I aortic dissection 4 years after the thoracoabdominal replacement. As a result, she underwent subtotal aortic replacement from the ascending aorta to the bilateral common iliac arteries in three stages. A 48-years-old female was admitted to our service because of acute heart failure and cardiogenic shock caused by acute DeBakey type I aortic dissection. She had undergone replacement of the descending thoracic aorta at the age of 44 and replacement of the remaining thoracoabdominal aorta with reimplantation of the four major abdominal branches at the age of 46 for a chronic expanding DeBakey type IIIb dissecting aneurysm. She successfully underwent replacement of the ascending aorta and the entire aortic arch with an aortic prosthesis provided with four branch grafts for reconstruction of the arch vessels. Considering the high incidence of new aortic lesion, extensive aortic replacement and careful postoperative follow-up are necessary in patients with Marfan's syndrome.

[Selective thermocoagulation of unresectable malignant tumors using radiofrequency]

Based on our experimental findings on porcine liver, we have been conducting a clinical trial of selective hyperthermia by radiofrequency (RF) capacitive heating with laparotomy for patients with unresectable malignant tumors. In 10 patients with malignant tumors (8 carcinoma of the pancreas, 2 carcinoma of the gallbladder), laparotomy and RF heating were performed after informed consent. The local heat coagulation was produced by heating equipment using 13.56 MHz radiofrequency produced by Omron Corporation, Japan. Four 2-cm electrode needles were placed in the tumor in a square array at intervals of 2.0 cm. Hyperthermia was given for 30 min with a controlled temperature of 50 degrees C in the RF field (2 x 2 x 2 cm3). That of the surrounding area was maintained at less than 40 degrees C. The calculated volume treated by RF ranged between (2 x 2 x 2 cm3) x 1 and (2 x 2 x 2 cm3) x 6. We followed all patients by computed tomographic (CT) scan 2 weeks after coagulation. Tumor markers in the blood were assayed before and 14 days after heating. Follow-up CT scans demonstrated that after the tumor mass had been heterogeneously enhanced, it changed to a homogeneous low-density area in 6 of 10 patients. The levels of tumor markers decreased to lower than the pre-treatment values in 9 of 10 patients. In all patients, the changes in CT scans and/or decrease in the markers were confirmed. Complications such as bleeding or abscess formation were not observed. It was suggested that the selective hyperthermia was safely produced by this equipment. The encouraging results in these patients justify further clinical trials.

Occurrence of Borrelia garinii oculo-neuroborreliosis in Japan

We report a 64-year-old Japanese man with oculo-neuroborreliosis. His clinical features consisted of polyarthralgia, keratoconjunctivitis, chorioretinitis, optic neuritis, confusion, and polyradiculitis. Assay of antibodies to Borrelia species detected IgG-antibody to B. garinii in both serum and CSF. Progressive declining of serum IgG antibody titer against Borrelia garinii, in parallel with clinical improvement, was observed after administration of ceftriaxone.

Separable cis-regulatory elements that contribute to tissue- and site-specific alpha 2(XI) collagen gene expression in the embryonic mouse cartilage

Type XI collagen is a structural component of the cartilage extracellular matrix and plays an important role in skeletal morphogenesis. As a step toward defining the molecular mechanisms responsible for the regulation of type XI collagen expression, we characterized the promoter region of the mouse alpha 2(XI) collagen gene (Coll1a2). We also generated transgenic mice harboring various fragments of the promoter and the first intron of Coll1a2 linked to the Escherichia coli beta-galactosidase gene to identify the cis-acting elements responsible for tissue- and site-specific expression during development. Cloning and sequence analysis of the 5' flanking region of Coll1a2 showed that the putative 3' end of the retinoid X receptor beta gene was located 742 bp upstream of the Coll1a2 start site. This suggested that the promoter region of Coll1a2 was localized within this 742-bp sequence, which contained multiple consensus regulatory elements. Examination of the transgenic mice revealed that the longest DNA construct (containing the entire promoter and first intron sequences) directed lacZ expression in the notochord as well as in the primordial cartilage throughout the body, with the pattern of expression mimicking that of endogenous Coll1a2 transcripts. On the other hand, deletion of the upstream approximately 290 bp resulted in the elimination of lacZ expression in the primordial cartilage of the carpals, tarsals, and vertebral bodies, whereas lacZ expression in the notochord and in the other primordial cartilage elsewhere was not affected. Deletion of the first intron sequence also resulted in the loss of lacZ expression in the primordial cartilage of the carpals, tarsals, and vertebral bodies, as well as in the notochord. These results demonstrate that the upstream 742-bp and first intron segments of the mouse Coll1a2 gene contain the necessary information to confer high level tissue-specific expression in mouse embryos. In addition, our observations suggest the presence of site-specific cis-acting elements that control Coll11a2 gene expression in different cartilaginous components of the skeleton.

A recurrent 1992delCT mutation of the type X collagen gene in a Japanese patient with Schmid metaphyseal chondrodysplasia

We report here a recurrent frameshift mutation within the carboxyl-terminal noncollagenous domain coding region of the type X collagen gene (COL10A1) in a Japanese patient with Schmid metaphyseal chondrodysplasia. The mutation involves deletion of a CT dinucleotide from position 1992 (1992delCT), and produces a frameshift which creates a premature termination codon close to the site of the deletion. The predicted length of the mutant polypeptide is 664 amino acids, which is shorter than the wild type polypeptide (680 amino acids). A 1992delCT mutation of COL10A1 has been previously reported in one family. The independent occurrence of de novo mutation of this specific dinucleotide repeat suggests that this region is a possible mutational hot spot on COL10A1.

Identification of the bud emergence gene BEM4 and its interactions with rho-type GTPases in Saccharomyces cerevisiae

The Rho-type GTPase Cdc42p is required for cell polarization and bud emergence in Saccharomyces cerevisiae. To identify genes whose functions are linked to CDC42, we screened for (i) multicopy suppressors of a Ts- cdc42 mutant, (ii) mutants that require multiple copies of CDC42 for survival, and (iii) mutations that display synthetic lethality with a partial-loss-of-function allele of CDC24, which encodes a guanine nucleotide exchange factor for Cdc42p. In all three screens, we identified a new gene, BEM4. Cells from which BEM4 was deleted were inviable at 37 degrees C. These cells became unbudded, large, and round, consistent with a model in which Bem4p acts together with Cdc42p in polarity establishment and bud emergence. In some strains, the ability of CDC42 to serve as a multicopy suppressor of the Ts- growth defect of deltabem4 cells required co-overexpression of Rho1p, which is an essential Rho-type GTPase necessary for cell wall integrity. This finding suggests that Bem4p also affects Rho1p function. Bem4p displayed two-hybrid interactions with Cdc42p, Rho1p, and two of the three other known yeast Rho-type GTPases, suggesting that Bem4p can interact with multiple Rho-type GTPases. Models for the role of Bem4p include that it serves as a chaperone or modulates the interaction of these GTPases with one or more of their targets or regulators.

Sustained ventricular tachycardias associated with myotonic dystrophy

Patients with myotonic dystrophy are reported to have a higher frequency of sudden death than the general population. Although causes of sudden death in myotonic dystrophy are suggested to be due to conduction of defects progressing, the HV interval cannot predict whether conduction system disease would develop or progress. We report two cases of myotonic dystrophy complicated with sustained monomorphic ventricular tachycardias (VT), which can cause sudden death. In Case No. 1, although the patient was treated successfully for sustained VT with verapamil in electrophysiologic studies, another sustained VT was confirmed 2 years later. In Case No. 2, the patient showed decreased left ventricular ejection fraction and late potentials, and induced sustained VT that was identical to clinically documented VT. Although VT is believed to be rare in patients with myotonic dystrophy, these cases suggest that VT is a possible cause of sudden death.