Spontaneously hyperlipidemic (SHL) mice: Japanese wild mice with apolipoprotein E deficiency

During inbreeding of Japanese wild mice (Mus musculus molossinus), we established a strain of mice with severe cutaneous xanthomatous lesions. Since those mice showed high plasma cholesterol values, we named them spontaneously hyperlipidemic (SHL) mice; total cholesterol values of these mice (even when fed on conventional low-fat diet) are unusually high throughout the life span. The xanthomatous lesions appear in palms and distal extremities of forelimbs as early as 4 weeks after birth, and continue to expand to chest, abdomen, and face until the mice die before 14 months of age. Histological examination of these lesions revealed cholesterol crystal deposits, an infiltration of foam cells or macrophages, while that of the vascular system revealed atherosclerosis in the aortic sinus. Immunoblot and Northern blot analyses failed to detect apolipoprotein E (APOE) expression in these animals. Consistent with these findings, Southern blot analysis found disruption of the Apoe gene in SHL mice. Phenotypes of SHL mice, however, were distinct from those of Apoetm1Unc (hereafter Apoe-/-) mice, whose Apoe gene was disrupted by homologous recombination; hypercholesterolemia and xanthoma were more severe in SHL mice than in Apoe-/- mice, while atherosclerosis was milder in SHL mice. These distinctions suggest that there are modifier genes for the phenotypes. Alternatively, other gene(s), besides the Apoe gene, may be mutated in SHL mice. In either case, comparative genetic and molecular dissection of SHL mice will provide a good opportunity to understand the genetic basis for hyperlipidemia and atherosclerosis.

Clinicopathological features of early gastric cancer: results of 100 cases from a rural general hospital

OBJECTIVE

To evaluate 100 patients with early gastric cancer from the point of view of early detection, clinicopathological variables, and long term results.

DESIGN

Retrospective study.

SETTING

Rural general hospital, Japan.

SUBJECTS

100 patients with early gastric cancer (confined to the epithelium, lamina propria, or submucosa) out of a total of 197 who had gastric cancers resected for cure between May 1986 and April 1996.

INTERVENTIONS

Subtotal gastrectomy (n = 87), total gastrectomy (n = 8), proximal gastrectomy (n = 2), and local wedge resection (n = 3).

MAIN OUTCOME MEASURES

Histopathological features and outcome.

RESULTS

The mean annual incidence of early gastric cancer was 51% (range 35%-70%). 16/59 patients with mucosal cancer (37%) and 18/41 with submucosal cancer (44%) presented with symptoms of the disease. The diagnosis was made in 62 by endoscopy, and in only 2 by upper gastrointestinal radiographic examination. None of the 59 with mucosal cancer had lymphatic invasion, and only 1 had a lymph node metastasis. Among the 41 with submucosal cancer, however, 15 had lymphatic invasion (37%), 13 had venous invasion (32%), and 2 had lymph node metastases (5%). 83 patients were alive with no sign of recurrence at the time of writing (median follow up 62 months, range 12-136). One patient with a tumour that produced alpha-fetoprotein died of hepatic metastases 23 months after subtotal gastrectomy. 9 patients developed second cancers, and 6 died of these with no signs of recurrence of early gastric cancer. The overall 5 and 10 year survival rates were 82% and 66%, and the corresponding disease-specific survival rates for 85 patients were both 98%.

CONCLUSIONS

Excellent long term results can be achieved in the treatment of early gastric cancer, even in a non-specialist centre. Patients with early gastric cancer should have their alpha-fetoprotein concentration measured, and be examined for the presence of other malignant disease both before and after treatment of the gastric cancer.

Prognostic significance of perioperative blood transfusions in resectable thoracic esophageal cancer

OBJECTIVE

The perioperative blood transfusions have been associated with tumor recurrence and decreased survival in various types of alimentary tract cancer. There exist, however, contradictory studies showing no relationship between blood transfusions and survival. For patients with esophageal cancer, only one report suggested that blood transfusions did not by itself decrease the chance of cure after esophagectomy.

METHODS

Among 235 patients with primary squamous cell carcinoma of the thoracic esophagus between December 1979 and March 1998, 143 patients (60.9%) underwent esophagectomy with curative intent (RO). To exclude the effects of surgery-related postoperative complications, 14 patients who died within 90 days during the hospital stay were excluded. Thus, clinicopathological characteristics and prognostic factors were retrospectively investigated between patients with no or few transfusions (< or = 2 units) (n = 58), and much transfused patients (> or = 3 units) (n = 71).

RESULTS

Sixty-three patients are alive and free of cancer, and 66 patients are dead. A total of 98 patients (76%) received blood transfusions, whereas 31 patients (24%) had no transfusion. The amount of blood transfused was 1 or 2 units in 27 patients (27.6%), 3 or 4 units in 33 (33.7%), 5 or 6 units in 20 (20.4%), and > or = 7 units in 18 (18.4%). The 5-yr survival rate for patients with no or few transfusions was 69%, whereas that for much transfused patients was 31.7% (p < 0.0001). The much transfused patients had more prominent ulcerative tumor, longer time of operation, more estimated blood loss, and more marked blood vessel invasion than the group with no or few transfusions. The factors influencing survival rate were tumor location, Borrmann classification, size of tumor, depth of invasion, number of lymph node metastases, time of operation, amount of blood transfusions, lymph vessel invasion, and blood vessel invasion. Among those nine significant variables verified by univariate analysis, independent prognostic factors for survival determined by multivariate analysis were number of lymph node metastasis (0 or 1 vs > or = 2, p < 0.0001), amount of blood transfusions (< or = 2 units vs > or = 3 units, p < 0.0001), and blood vessel invasion (marked vs non-marked, p = 0.0207).

CONCLUSIONS

There is an association between high amount of blood transfusions and decreased survival for patients with resectable esophageal cancer. To improve the prognosis, surgeons must be careful to reduce blood loss during esophagectomy with extensive lymph node dissection and subsequently must minimize blood transfusions.

Management of incidentally discovered adrenal masses

The incidental discovery of adrenal masses in radiologic imaging studies is becoming increasingly common. Herein we present our experience with 59 cases of incidentally discovered and surgically removed adrenal masses. Of 59 adrenal incidentalomas, 15 cases were hypersecretory tumors, including 11 pheochromocytomas; only 3 were adrenocortical carcinomas. The prevalence of incidentally discovered adrenal masses and their differential diagnosis and management are discussed in a review of the literature.

An essential role for nuclear factor kappa B in preventing TNF-alpha-induced cell death in prostate cancer cells

PURPOSE

Although tumor necrosis factor-alpha (TNF-alpha) induces a strong cytotoxic effect on cell growth, many authors have reported that various cancer cells are resistant to TNF-alpha and the basis for this sensitivity or resistance to TNF-alpha remains to be elucidated. Since nuclear factor kappa B (NF-kappaB) activation has recently been reported to inhibit TNF-alpha-induced cell death, we studied whether NF-kappaB also assumes a protective role in TNF-alpha-induced cell death in prostate cancer cells.

MATERIALS AND METHODS

We used two human prostate cancer cell lines of DU145 and PC-3. We prepared two different NF-kappaB inhibitors, pyrrolidine dithiocarbamate (PDTC) and NF-kappaB decoy. NF-kappaB DNA binding activity was detected by electrophoretic mobility shift assay (EMSA). Cell survivals were measured by MTT assay. Induction of apoptosis was detected by nuclear staining and measured by fragmented DNA ELISA.

RESULTS

EMSA showed that NF-kappaB inhibitors continuously inhibited TNF-alpha-induced NF-kappaB activation. Cell growth was not inhibited by either TNF-alpha (50 ng./ml. or less) or NF-kappaB inhibitors. However, both PCA cells treated with TNF-alpha (20 ng./ml.) plus NF-kappaB inhibitors showed significant growth inhibition compared with controls (p<0.05). Nuclei of PCA cells appeared severely fragmented by this combination therapy. Furthermore, the levels of DNA fragmentation were significantly elevated in PCA cells treated with TNF-alpha (20 ng./ml.) plus NF-kappaB inhibitors compared with controls (p<0.05).

CONCLUSIONS

NF-kappaB activation is suggested to produce the resistance of DU145 and PC-3 to TNF-alpha and that the combination of TNF-alpha and NF-kappaB inhibitors could be constituted an effective therapy to TNF-alpha-resistant human prostate cancer cells.

[In vitro activities of 23 antimicrobial agents against 4,993 gram-positive and gram-negative bacterial strains isolated from multicenter of Japan during 1994--in vitro susceptibility surveillance.Levofloxacin-Surveillance Group]

In a surveillance study conducted during 1994 at 24 medical institutes from different geographical areas of Japan, the susceptibility of clinical isolates to twenty three comparative agents, such as ofloxacin, levofloxacin, ciprofloxacin, tosufloxacin, ampicillin, clavulanic acid/amoxicillin, oxacillin, piperacillin, cefaclor, cefotiam, cefdinir, cefclidin, ceftazidime, cefpirome, imipenem, aztreonam, vancomycin, minocycline, chloramphenicol, clarithromycin, sulfamethoxazole/trimethoprim, amikacin, and gentamicin, were tested by the standard broth micro-dilution method. A total of 4,993 isolates tested in this study included Streptococcus pneumoniae, methicillin susceptible Staphylococcus aureus (MSSA), methicillin resistant Staphylococcus aureus (MRSA), coagllase negative streptococci (CNS), Enterococcus faecalis, Enterococcus faecium, Enterobactericeae, Pseudomonas aeruginosa from patients with urinary tract infections or respiratory tract infections, and Haemophilus influenzae. For MSSA, S. pneumoniae, Enterobacteriaceae, and H. influenzae, more than 70% of the isolates was susceptible to fluoloquinolones. However, resistance occurred in more than 50% of MRSA and P. aeruginosa isolated from UTI. Fluoroquinolones were found to be effective against high level penicillin-resistant S. pneumoniae, the third generation cephem-resistant Enterobacteriaceae and ampicillin-resistant H. influenzae.

A genetic linkage map of rat chromosome 9 with a new locus for variant activity of liver aldehyde oxidase

A genetic linkage map of rat chromosome 9 consisting of five loci including a new biochemical marker representing a genetic variation of the activity of the liver aldehyde oxidase, (Aox) was constructed. Linkage analysis of the five loci among 92 backcross progeny of (WKS/Iar x IS/Iar)F1 x WKS/Iar revealed significant linkages between these loci. Minimizing crossover frequency resulted in the best gene order: Aox-D9Mit4-Gls-Cryg-Tp53l1. The homologues of the Cryg, Gls, and Aox genes have been mapped on mouse chromosome 1 and human chromosome 2q. The present findings provide further evidence for the conservation of synteny among these regions of rat, mouse, and human chromosomes.

Prognostic factors in T1 and T2 squamous cell carcinoma of the thoracic esophagus

BACKGROUND

Prognostic indicators in patients with T2 tumor have not been fully understood.

OBJECTIVE

To clarify the clinicopathologic characteristics and long-term results of T1 and T2 squamous cell carcinomas of the thoracic esophagus.

DESIGN

Consecutive case series.

SETTING

Department of surgery in a university hospital.

PATIENTS

Of 234 patients with primary squamous cell carcinoma of the thoracic esophagus, 142 patients underwent esophagectomy with curative intent: 97 patients had pT1 and pT2 tumors.

INTERVENTIONS

Investigated were clinicopathologic characteristics of 65 of 97 patients with pT1 and pT2 tumors; excluded were 7 patients who died of postoperative complications and another 25 patients who died of causes other than esophageal cancer.

MAIN OUTCOME MEASURES

Clinicopathologic characteristics and long-term results.

RESULTS

Pathologic tumor stages were pT1 N0 in 23 patients, pT1 N(+) in 7 patients, pT2 N0 in 15 patients, and pT2 N(+) in 20 patients. Fifty patients are alive and free of cancer and 15 patients died of tumor recurrence (1 patient with pT1 N0 tumor, 1 patient with pT1 N[+][+] tumor, 1 patient with pT2 N0 tumor, and 12 patients with pT2 N[+] tumor). The sites of metastatic nodes in 6 survivors with pT1 N(+) tumor were a solitary perigastric node in 4 patients, a solitary mediastinal node in 1 patient, and 2 mediastinal nodes in 1 patient. The 5-year survival rates of patients with pT1 N0, pT1 N(+), and pT2 N0 tumors all exceeded 85%, and the rate of those with pT2 N(+) tumor was 33.9% (pT2 N[+] vs. others: pT1 N0, pT1 N[+], and pT2 N0; P = .003). The factors affecting survival rate by univariate analysis were Borrmann classification (0, 1 vs. 2, 3, 4), tumor size (<4.0 vs. > or =4.0 cm), combined T, N factor (pT2 N[+] vs. others), time of operation (< or =420 vs. >420 minutes), estimated blood loss (<1000 vs. > or =1000 mL), and lymph vessel invasion (marked vs. not marked). Stage pT2 N(+) tumor became a single independent prognostic factor for survival as determined by multivariate analysis (pT2 N[+] vs. others; P = .008).

CONCLUSIONS

Stage pT1 N(+) tumors with a few diseased nodes and pT2 N0 tumors are considered to be a group with an excellent prognosis, similar to pT1 N0 tumors. Patients with pT2 N(+) diseases had worse prognoses and thus should have meticulous lymph node dissection and extensive adjuvant therapy.

Induction of apoptosis of cytokine-producing bladder cancer cells by adenovirus-mediated IkappaBalpha overexpression

We investigated whether the cell growth and apoptosis of multiple cytokine-producing bladder cancer cells can be regulated by nuclear factor kappaB (NF-kappaB). The bladder cancer cell line KU-19-19, obtained from a 76-year-old man who demonstrated marked leukocytosis, produces multiple cytokines and demonstrates autocrine growth by granulocyte colony-stimulating factor (G-CSF). Electrophoretic mobility shift assay (EMSA) revealed that NF-kappaB was activated in KU-19-19 but not in other bladder cancer cell lines (KU-1, KU-7, or T-24, respectively). The inhibition of NF-kappaB DNA-binding activity with adenovirus vectors expressing the stable form of the NF-kappaB inhibitor IkappaBalpha (multiplicity of infection [MOI] of 10) inhibited growth and induced apoptosis of KU-19-19, but not KU-1, KU-7, or T-24. The production of several cytokines was suppressed significantly in KU-19-19 by this gene delivery. Although dexamethasone (10 microM) could also suppress cytokine production, it did not induce dramatic cell death in KU-19-19 because it could not inhibit NF-kappaB activation stably and strongly. These results suggest that NF-kappaB activation maintains the cell viability as well as regulates cytokine production in cytokine-producing cancer cells and therefore these in vitro experiments support a rationale for preclinical in vivo studies to demonstrate growth inhibition in established tumors.

[Pulmonary vein reconstruction for lung carcinoma]

Four cases of primary lung carcinoma (two squamous cell carcinomas and two adenocarcinomas) were performed right middle lobectomy combination with the reconstruction of upper pulmonary vein to remain the upper lobe. Lung carcinomas were in the right lobe and infiltrated to lower margin of upper pulmonary vein in all cases. After resection of the right middle lobe and an affected portion of upper pulmonary vein, the defect of the upper pulmonary vein was replaced with auto-pericardial graft in three cases, and the other one was closed by continuous suture of 5-0 plorene. Pathological classification of these four cases was stage IB in one patient, stage IIB in two and stage IV in one. All patients died from 6 to 53 months after operation (average: 31 months). Metastasis to distant organs was confirmed in all cases, so the prognosis of them was generally poor. Reconstruction of pulmonary vein may be feasible to avoid over resection of other lobes, because pulmonary function can be preserve as well as in the bronchoplasty.

Prognostic factors after hepatic resection for hepatocellular carcinoma associated with Child-Turcotte class B and C cirrhosis

OBJECTIVE

To evaluate prognostic factors after resection of hepatocellular carcinoma (HCC) in patients with Child-Turcotte class B and C cirrhosis.

SUMMARY BACKGROUND DATA

Although hepatic resection remains the mainstay in the treatment of HCC and can be performed with low morbidity and mortality rates in patients without cirrhosis, its role is poorly defined for patients with severe cirrhosis.

METHODS

From 1986 to 1996, partial hepatectomy was performed for HCC in 63 patients with Child-Turcotte class B (n = 46) and C (n = 17) cirrhosis. There were 46 men and 17 women, with an average age of 61.2 years (range 35 to 79 years). Associated conditions were diabetes mellitus in 45, esophageal varices in 32, severe hypersplenism in 26, cholelithiasis in 13, gastroduodenal ulcer in 6, and hiatal hernia, gastric lymphoma, splenic abscess, and pancreatic cyst each in 1. Concomitant surgical procedures were performed for most of these conditions.

RESULTS

Major complications occurred in 17 patients (27%), six (9.5%) of whom died within 1 month after surgery. The overall in-hospital death rate was 14.3%. Liver failure and intraabdominal sepsis were mostly fatal complications. The overall and disease-free survival rates, respectively, were 70.2% and 64.5% at 1 year, 43.5% and 23.8% at 3 years, and 21.4% and 14.9% at 5 years. Multivariate analysis with the Cox regression model revealed that favorable factors for survival were Child class B, no transcatheter arterial embolization before surgery, young age, and low alanine aminotransferase (ALT) level before surgery.

CONCLUSIONS

Hepatic resection can provide a favorable result in young patients with HCC complicating Child class B cirrhosis with low hepatitis activity, but transcatheter arterial embolization before surgery should be avoided in such patients.

Co-localization of HSV-1 DNA and ICP35 protein by in situ hybridization and immunocytochemistry

In an effort to obtain a better signal-to-noise ratio and ultrastructural preservation, we sought to improve electron microscopic in situ hybridization technique. In our method, protease treatment was omitted and visualization of the digoxigenin (DIG)-labelled deoxyribonucleic acid (DNA)-probe was enhanced using a three-step procedure. These improvements allowed us to localize viral DNA with good signal-to-noise ratio. DNA specific to herpes simplex virus 1 (HSV-1) was localized by this method to HSV-1 infected cultured cells; DNA was not observed in the empty-cored HSV-1. Using this method and the immunogold cytochemical method, we co-localized viral DNA and capsid protein ICP35 on Lowicryl-embedded sections of HSV-1 infected cells. Interestingly, labelling for both DNA and ICP was observed on some HSV-1 particles in cell nucleus. This finding is consistent with the notion that ICP35 is necessary for assembly of viral DNA. Combination of in situ hybridization and immunocytochemical techniques is a powerful tool for examination of the functional relationship between viral DNA and proteins and help us to study protein function in viral multiplication.

Sequence polymorphism in two novel Plasmodium vivax ookinete surface proteins, Pvs25 and Pvs28, that are malaria transmission-blocking vaccine candidates

BACKGROUND

For many malarious regions outside of Africa, development of effective transmission-blocking vaccines will require coverage against both Plasmodium falciparum and P. vivax. Work on P. vivax transmission-blocking vaccines has been hampered by the inability to clone the vaccine candidate genes from this parasite.

MATERIALS AND METHODS

To search for genes encoding the ookinete surface proteins from P. vivax, the DNA sequences of the eight known proteins in the P25 subfamily (Pfs25, Pgs25, Pys25, Pbs25) and in the P21/28 subfamily (Pfs28, Pgs28, Pys21, Pbs21) of zygote/ookinete surface proteins were aligned. Regions of highest identity were used to design degenerate PCR oligonucleotides. Genomic DNA from the Sal I strain of P. vivax and genomic and splinkerette DNA libraries were used as PCR templates. To characterize the polymorphisms of Pvs25 and Pvs28, these two genes were PCR amplified and the DNA sequences were determined from genomic DNA extracted from patients infected with P. vivax.

RESULTS

Analysis of the deduced amino acid sequence of Pvs28 revealed a secretory signal sequence, four epidermal growth factor (EGF)-like domains, six copies of the heptad amino acid repeat (GSGGE/D), and a short hydrophobic region. Because the fourth EGF-like domain has four rather than six cysteines, the gene designated Pvs28 is the presumed homologue of P21/28 subfamily members. Analysis of the deduced amino acid sequence of Pvs25 revealed a similar structure to that of Pvs28. The presence of six rather than four cysteines in the fourth EGF-like domain suggested that Pvs25 is the homologue of P25 subfamily members. Several regions of genetic polymorphisms in Pvs25 and Pvs28 were identified in field isolates of P. vivax.

CONCLUSIONS

The genes encoding two ookinete surface proteins, Pvs28 and Pvs25, from P. vivax have been isolated and sequenced. Comparison of the primary structures of Pvs25, Pvs28, Pfs25, and Pfs28 suggest that there are regions of genetic polymorphism in the P25 and P21/28 subfamilies.

Overexpression of transforming growth factor-beta1 in scirrhous carcinoma of the stomach correlates with decreased survival

A retrospective study of 50 patients with scirrhous carcinoma of the stomach who had undergone surgery was performed to elucidate whether immunohistochemical overexpression of transforming growth factor-beta1 (TGF-beta1) could predict the patients' survival. To evaluate the proliferative activity of the tumor, the proliferating cell nuclear antigen (PCNA) index was used. Expression of TGF-beta1 was low in 27 patients and high in 23. Clinicopathological characteristics were not significantly different between the two groups with high and low TGF-beta1 expression. Tumors with higher TGF-beta1 expression had higher PCNA indices (p = 0.0467, unpaired Student's t test). The 5-year survival rate was 40.4% for the low TGF-beta1 group and 28.7% for the high TGF-beta1 group (p = 0.0388, log rank test). By multivariate analysis, pT, residual tumor, and TGF-beta1 were the independent prognostic factors. These results suggest that immunohistochemical expression of TGF-beta1 is one of the useful predictors for estimating the patients' survival in scirrhous carcinoma of the stomach particularly of the T3 and T4 stages.

Submillisecond kinetics of glutamate release from a sensory synapse

Exocytosis-mediated glutamate release from ribbon-type synaptic terminals of retinal bipolar cells was studied using AMPA receptors and simultaneous membrane capacitance measurements. Release onset (delay <0.8 ms) and offset were closely tied to Ca2+ channel opening and closing. Asynchronous release was not copious and we estimate that there are approximately 5 Ca2+ channels per docked synaptic vesicle. Depending on Ca2+ current amplitude, release occurred in a single fast bout or in two successive bouts with fast and slow onset kinetics. The second, slower bout may reflect a mobilization rate of reserve vesicles toward fusion sites that is accelerated by increasing Ca2+ influx. Bipolar cell synaptic ribbons thus are remarkably versatile signal transducers, capable of transmitting rapidly changing sensory input, as well as sustained stimuli, due to their large pool of releasable vesicles.

Tumor vascularity predicts recurrence in differentiated thyroid carcinoma

BACKGROUND

New prognosticators are necessary for optimizing the extent of thyroidectomy and adjuvant radiotherapy in differentiated thyroid carcinoma.

METHODS

Tumor microvessel density (MVD), expression of thymidine phosphorylase (dThdPase) and CD68 stained macrophages were evaluated in 71 differentiated thyroid carcinomas by an immunohistochemical method.

RESULTS

The recurrence-free survival was significantly (P <0.05) shorter in patients with hypervascular tumors but was not related to the dThdPase expression. Significant (R = 0.323, P <0.001) correlation between dThdPase expression score and increment in MVD was documented. Frequent high MVD and dThdPase expression were encountered in tumors >3 cm. Twenty-two of the 27 (82%) patients expressing high dThdPase were also evaluated positive for CD68 (P <0.001).

CONCLUSIONS

Tumor MVD might be a new prognostic indicator of differentiated thyroid carcinoma, whereas dThdpase expression with high MVD might serve to identify a subgroup of thyroid carcinoma patients as potential candidates for adjuvant radiotherapy.

Reproductive study. II: Prenatal and postnatal development study with candoxatril in Sprague-Dawley rats

Candoxatril, a prodrug for candoxatrilat, a selective inhibitor of neutral endopeptidase, was administered orally to groups of 24 female rats at doses of 0, 120, 400 or 1200 mg/kg/day from gestation day 6 to lactation day 21 to assess effects on pre- and postnatal development of F1 offspring. All dams were allowed to litter and to raise their F1 offspring until lactation day 21. The F1 offspring were examined for postnatal developmental indices, reflex behaviors and memory. A functional observational battery (FOB) was also conducted. A marked increase in spontaneous activity of the dams was observed in all candoxatril-treated groups. Maternal body weight gain was decreased in the 400 and 1200 mg/kg/day groups during the treatment periods. No significant differences were found for reproductive parameters. The male and female pups in the 1200 mg/kg/day group had significantly lower body weights beginning on postnatal days 21 and 14, respectively, through to the end of the study. There were no drug-related effects on pre- and postnatal developmental indices, FOB, sensory function tests or memory test. The no observed adverse effect levels were 120 and 400 mg/kg/day for the F0 dams and F1 offspring, respectively.

Potentiation of transmitter release by protein kinase C in goldfish retinal bipolar cells

1. We examined whether transmitter release could be modified by the activation of protein kinase C (PKC) of retinal bipolar cells. A bipolar cell with a large axon terminal was isolated from the goldfish retina. The presynaptic Ca2+ current was measured under whole-cell voltage clamp, and the released transmitter (probably glutamate) was detected electrophysiologically by using the response of NMDA receptors of catfish horizontal cells as a reporter. 2. Transmitter release was potentiated by a PKC activator, phorbol 12-myristate 13-acetate (PMA), but not by an ineffective phorbol ester, 4alpha-phorbol 12,13-didecanoate. A PKC inhibitor, bisindolylmaleimide I, did not affect the transmitter release by itself but blocked the PMA-induced potentiation of transmitter release. These results suggest that the actions of PMA were mediated via the activation of PKC. 3. Introduction of 5 mM EGTA into the presynaptic terminals of bipolar cells revealed two separate components of transmitter release. A rapid component was triggered immediately after depolarization while a slow component appeared with a delay. Application of PMA selectively potentiated the slow component without affecting the Ca2+ dependence of exocytosis. 4. We suggest that the activation of PKC may modify the recruitment process of synaptic vesicles in retinal bipolar cells.

Pulmonary embolism in patients with isolated soleal vein thrombosis

This study investigated the features of calf deep vein thrombosis (DVT) as a pulmonary embolic source. Fifty-eight lower limbs in 29 patients who were suspected of having DVT distal to the popliteal vein were screened by ultrasonography. Then, ascending venography was performed to confirm the diagnosis. Pulmonary embolism (PE) was diagnosed in suspected patients by use of pulmonary perfusion scanning or pulmonary angiography. Venography revealed calf DVT in 33 limbs in 28 patients. Of 28 patients, six had symptomatic PE. Thrombosis was found in the muscle veins in 18 limbs, the trunk veins in 11, and both veins in four. Isolated single vein thrombosis was found in the soleal vein in 14 limbs (42%), the posterior tibial vein in eight, the peroneal vein in two, and the gastrocnemius vein in two. The overall percentage of soleal vein thrombi was 61%. All six patients with symptomatic PE had isolated soleal vein thromboses. Calf DVT was a pulmonary embolic source when isolated thrombosis of the large soleal vein was more than 7 mm in diameter. Soleal veins were the most frequent and important location of calf DVT, suggesting that these were an occasional embolic source of critical PE.

[Clinical background and treatment of brain metastasis from renal cell carcinoma]

OBJECTIVE

The objective of this study is to evaluate the clinicopathological characteristics and the effect of therapy of brain metastasis from renal cell carcinoma.

METHOD

Of 306 cases with renal cell carcinoma treated at Keio University Hospital from June, 1976 to May, 1996, 20 (6.5%) developed brain metastasis. Metastasis-free rate and survival rate were evaluated by Kaplan-Meier's method and tested statistically with Long-rank test.

RESULT

As for the time of the brain metastasis, it was already at the time of initial diagnosis in 6 cases, and in the other 14, it was after the diagnosis of original disease. The average interval between the diagnosis of original disease and metastasis was 53.9 months. Only 2 cases have no metastasis without brain, and 17 of 20 cases (85.0%) were complicated by pulmonary metastasis and 10 (50.0%) by bone metastasis. It was considered that the brain metastasis was accompanied with other metastases. As for the treatment, cytokine therapy was performed on 18 cases without efficacy. It was supposed that in cases with pulmonary metastasis, IL-2 therapy may have the possibility of increasing the frequency of brain metastasis. 9 of 20 cases were subjected to surgical treatment with significantly better prognosis than the cases without the operation. Two cases were long-term survivors more than 5 years after the diagnosis of brain metastasis and both underwent surgical treatment to brain metastasis.

CONCLUSION

Cytokine therapy was not effective to brain metastasis from renal cell carcinoma. On the other hand, however, it was suggested that surgical treatment could improve prognosis if the metastatic lesions could be resected.

A second p53-related protein, p73L, with high homology to p73

The p53 protein, which regulates the rate of cell division and death, is the most frequently mutated tumor suppressor to be identified so far in human cancers. Recently, a gene with significant homology to p53, termed p73, has been identified in a chromosomal region that is implicated in the molecular pathogenesis of neuroblastoma. We have cloned a second human p53-related gene, termed p73L, which shows strong amino-acid similarity to p73. The p73L gene is mapped to human chromosome 3q27-28 using in situ hybridization technique. p73L encodes a protein of 586 amino acids and its putative DNA binding domain (DBD) has high identities to those of p53 (60.6%) and to p73 (87.8%). Northern blot analysis, which demonstrated that the expression profiles of p73L and p73 mRNAs are distinct in some tissues, implies that p73 and p73L may have separate, distinct roles in different tissues.

Duodenum-preserving resection of the pancreatic head for mucinous ductal ectasia without overt carcinoma

BACKGROUND/AIMS

The clinical characteristics of mucinous ductal ectasia (MDE) of the pancreas without overt carcinoma have not been clarified. To clarify MDE and assess the optimal treatment procedure, including the technique of duodenum-preserving resection of the pancreatic head (DpRPH), we studied four patients.

METHODOLOGY

Our patients consisted of three men and one woman, with a mean age of 71 years. The patients underwent DpRPH (n=3) or the pylorus-preserving Whipple procedure (PpW) (n=1). Clinicopathological features, postoperative pancreatic function, and technique to preserve duodenal blood flow were studied.

RESULTS

All patients had intraductal mucin-hypersecretion and multilocular cysts lined by hyperplastic epithelium. The lesions were located in the uncinate process (n=3) or head-body (n=1) of the pancreas. DpRPH totally removed the lesions in the uncinate process. Of the three patients receiving DpRPH, dusky duodenum and a postoperative duodenal ulcer developed in two whose gastroduodenal arteries (GDA) were divided, but did not develop in one with undivided GDA. Postoperative glucose tolerance test and peptide para-aminobenzoic acid test after DpRPH showed better values than those after PpW. All patients are alive and well 22 to 40 months after surgery.

CONCLUSIONS

DpRPH is a new standard for MDE. During DpRPH, preservation of the GDA and the superior portion of the pancreatic head is recommended to maintain an adequate duodenal blood flow.

Association between tumor necrosis factor in serum and cachexia in patients with prostate cancer

The present study was undertaken to evaluate the relationship between serum tumor necrosis factor (TNF) and cachexia in patients with prostate cancer. TNF levels were determined in 110 serum samples from prostate cancer patients by an enzyme immunoassay. Serum TNF activity was positive in 76% of the patients with relapsed disease, whereas only 11% of the untreated patients and 0% of the patients in remission as a result of endocrine therapy were positive. The serum total protein and albumin levels, hemoglobin levels, and body mass index of the patients with elevated serum TNF levels were significantly lower (P < 0.05) than the corresponding values in patients with undetectable serum TNF levels. The serum TNF levels of patients with serum albumin levels of <3.5 g/dl, serum total protein levels of <7.0 g/dl, hemoglobin levels of <11.0 g/dl, and a body mass index of <21 kg/m2 were significantly higher (P < 0.05) than the values in their respective counterparts. There was a significant correlation between the detectability of serum TNF and performance status (P < 0.05). Patients with elevated serum TNF levels had a significantly higher mortality rate (P < 0.05) than those with undetectable serum TNF levels. These findings suggest that TNF may be one of the factors contributing to the complex syndrome of cachexia in patients with prostate cancer.