Interleukin-6 may mediate malnutrition in chronic hemodialysis patients

Studies were performed to investigate the relationship between serum interleukin-6 (IL-6) and the nutritional status in chronic hemodialysis patients. Serum IL-6 in 45 patients (21 men and 24 women), each with chronic renal failure and having undergone hemodialysis for more than 3 years, was measured before and after a dialysis session. The nutritional status of each patient was evaluated by measuring body mass index (BMI), body weight loss for 3 years, midarm muscle area (MAMA), serum albumin, prealbumin, and insulin-like growth factor-1. Serum IL-6 was significantly higher in the patients undergoing hemodialysis (11.7 +/- 2.8 pg/mL) than in healthy volunteers (< 0.6 pg/mL). There was no further increase in serum IL-6 after a dialysis session when the extracellular water volume was corrected by the ultrafiltrate volume. Predialytic serum IL-6 was significantly correlated with serum albumin (r = -0.4, P = 0.006), cholinesterase (r = -0.51, P = 0.001), body weight change for 3 years (r = -0.48, P = 0.001) and MAMA r = -0.39, P = 0.05). With the patients divided into two groups, a high serum IL-6 (>10 pg/mL) group and low serum IL-6 (<10 pg/mL) group, the body weight loss for 3 years (-4.60% +/- 1.39% v 0.76 +/- 0.75%, P < 0.01) was significantly higher, and the serum albumin level (3.66 +/- 0.10 g/dL v 3.96 +/- 0.05 g/dL, P < 0.05) was significantly lower in those patients with high serum IL-6 than in those with low serum IL-6. The results of a multiple regression analysis indicated that the serum IL-6 level was dependent on the duration of hemodialysis, age, and the dialysis membrane properties. These results suggest that the nutritional status in chronic hemodialysis patients was affected, at least in part, by the circulating IL-6 level. Multiple factors, such as long-term hemodialysis, aging, and the use of a regenerated cellulose membrane dialyzer, were associated with this increased level of IL-6.

Iron chelation by chlorogenic acid as a natural antioxidant

Chlorogenic acid, a dietary antioxidant, effectively inhibited the iron-induced lipid peroxidation of bovine liver microsomes in a concentration-dependent manner. In the Fenton-type reaction, chlorogenic acid inhibited the production of the hydroxyl radical by iron-EDTA or iron-ADP, while iron plus chlorogenic acid did not generate the hydroxyl radical. The formation of an iron complex with chlorogenic acid was demonstrated by UV/vis absorbance spectroscopic, ESR and 1H-NMR studies. The ferric complex with chlorogenic acid was in the ferric high-spin state near rhombicity, and had no radical scavenging activity. The results indicate that chlorogenic acid prevented the formation of the hydroxyl radical by forming a chelate with iron whose complex cannot catalyze the Fenton-type reaction.

Fatigue resistance of titanium-nickel alloy cast clasps

In this study fatigue resistance of experimentally prepared titanium-nickel (50.8% nickel and 49.2% titanium) cast clasps was evaluated in a simulated clinical situation. The change in force required to remove the titanium-nickel clasps was recorded under a repeated placement-and-removal test on steel model abutment teeth. Commercially-pure titanium, cobalt-chromium alloy, and gold-silver-palladium-copper alloy clasps were also tested for comparison. The tips of the clasps were located in the 0.25- and 0.50-mm undercut areas of the abutments. No significant changes in the retentive force were found in titanium-nickel clasps in the 1,010 repeated cycles, whereas the other three types of clasp revealed a significant decrease in the force required for removal during the test procedures (repeated analysis of variance P < 0.001). The results suggest that the cast titanium-nickel clasp may be suitable in removable prosthodontic constructions because of its significantly less permanent deformation during service. This report also discusses clinical applicability and some current problems with this new application.

The protective effects of prostaglandin E1 on sinusoidal endothelial cells in xenogeneic pig liver perfusion

The effects of prostaglandin E1 (PGE1) on hepatic sinusoidal endothelial cells (SEC) in the xenogeneic immunoreaction were investigated. Porcine livers were perfused with fresh human blood via the portal vein (PV) and the hepatic artery (HA) either with the administration of PGE1 (Group PG) or without PGE1 (Group C). The creatine kinase-BB component (CK-BB) in the perfusate was measured to assess SEC damage. SEC activation and complement activation were evaluated immunohistochemically by the expression of von Willebrand factor (vWF) and by the deposition of membrane attack complex (MAC), respectively. Xenoperfusion in Group C was discontinued between 4 and 6 hr due to the rapid elevation of HA pressures and the massive loss of perfusate. In Group PG, both PV and HA pressures were kept stable for up to 9 hr. In Group C, severe interlobular bleeding and diffuse extrasinusoidal hemorrhage were observed at 4 hr histologically, while in Group PG, the hepatic architecture was maintained without hemorrhage at 6 hr. MAC was markedly deposited on SEC and parenchymal cells at 3 hr in both groups. The amount of vWF, however, was expressed on SEC in large amounts at 1 hr in Group C, while small amounts were expressed at 1 hr in Group PG. In Group PG, CK-BB release was significantly lower than in Group C (P < 0.01). These results suggest that PGE1 suppressed SEC activation and protected the impairment of hepatic SEC during xenoperfusion without suppressing complement activation, resulting in the prolongation of xenogeneic liver perfusion.

Humoral injury in porcine livers perfused with human whole blood

BACKGROUND

We investigated the influence of humoral injury during xenoperfusion of porcine livers by human blood.

METHODS

The porcine livers were perfused under physiological conditions for 9 hr. The perfusates consisted of porcine whole blood in group 1, human whole blood in group 2, and human whole blood with soluble complement receptor type 1 (300 microg/ml) in group 3.

RESULTS

Liver enzyme release and serum hemoglobin in group 2 increased significantly after 3 hr of xenoperfusion, compared with those in group 1 and group 3 (P<0.05). Severe histological damage with minimal cellular infiltration was observed in group 2 after 6 hr of xenoperfusion, but was present only at trace levels in group 1 and group 3. In group 2, von Willebrand factor, a possible target of natural antibodies, was induced on sinusoidal endothelial cells after 3 hr of xenoperfusion, correlating with diffuse deposition of human IgM and membrane attack complex. In group 3, von Willebrand factor, human IgM, and membrane attack complex staining in the intralobular region were present at trace levels. In group 3, the indocyanine green removal capacity, representing hepatocyte function, was significantly higher than in group 2 (P<0.05).

CONCLUSIONS

Based on these results, we suggest that humoral injury is a major cause of liver damage during liver xenoperfusion. The pattern of humoral injury in xenoperfused livers may be attributed to anatomical features of the liver and unique responses of sinusoidal endothelial cells to xenoperfusion.

Variations of the natural abundances of nitrogen and carbon isotopes in Triticum aestivum, with special reference to phloem and xylem exudates

This work explored whether the natural abundances of carbon and nitrogen isotopes could be used to describe the movement of C and X within wheat plants; we also considered whether isotopic analyses of aphids or their honeydew would substitute for direct analysis of phloem exudate. The δ¹³ C of ears and roots (sinks) most closely matched those of the sugars + organic acids fraction (sources) in both growth stages; phloem δ¹³ C matched that of leaf blade sugars. Xylem exudate δ¹³ C matched no other putative (and measured) source in the ear-forming stage and matched that of whole roots and ears in the grain-filling stage. The δ¹⁵ N of grain and roots (sinks) resembled that of leaf amino acids (sources) in the ear-forming stage. In the gram-filling stage, ear δ¹⁵ N continued to resemble that of leaf amino acids, and δ¹⁵ N of roots most closely resembled that of whole leaves. In the grain-filling stage, phloem δ¹⁵ N fell between that of leaf blade amino acids and that of whole leaves and was ¹⁵ X-depleted relative to internal and external NO, -N. In both growth stages, xylem exudate δ¹⁵ N was less than that of soil NO₃ ^- -N and more than that of residual soil N after mineral N extraction. The isotopic values are generally in agreement with data from other approaches, such as isotope labelling; they show NO₃ ^- -N reduction in both shoots and roots of wheat and significant N recycling (root-shoot-phloem-root) and C movement. Aphids might serve as a substitute for isotopic analysis of phloem δ¹⁵ N. having the same value as their food source. Their excreta was ¹⁵ N-enriched relative to phloem.

Prophylactic perioperative treatment in a patient with colon carcinoma complicated by polycythemia vera

A patient with colon carcinoma complicated by polycythemia vera (PV) who underwent a partial colectomy concomitant with prophylactic perioperative treatment resulting in successful outcome is herein described. Seven weeks after the cessation of the latest exacerbation of PV, a partial colectomy was performed. In order to prevent the development of disseminated intravascular coagulation and thrombotic complications, the following perioperative treatment was performed: administration of gabexate mesilate (2,000 mg/day), fresh frozen plasma (300 ml/day), heparin (5,000 IU/day) for 7 days and anti-thrombin-III for 4 days, and a potent antibiotic therapy for 12 days and graded elastic bandages around the bilateral lower extremities for 14 days. As a result, an uneventful postoperative course was achieved. The present case suggests that these treatments are useful in the perioperative management of PV patients.

Suboptimal dual adaptive control for blood pressure management

This paper presents a new approach for adaptive control of blood pressure using vasoactive drugs. The idea is to use an adaptive controller that incorporates the concept of duality in the sense of Feldbaum and to consider the cost functional M-steps ahead in time. The dual property means that the control signal is chosen in such a way that estimation of the model parameters and regulation of the output signals are optimally balanced. Extensive computer simulations for different values of M shows that the sample mean of the achieved cost tends asymptotically to a limiting value while the variance is reduced. The proposed subotimal adaptive controller has also an improved transient response when compared to a certainty equivalent controller.

[Luteinizing hormone-releasing hormone for prostate cancer in a hemodialysis patient: a case report]

An 81-year-old man on chronic hemodialysis was referred to our hospital with urinary difficulty. Transperineal needle biopsy of a hard nodule in the prostate revealed moderately differentiated adenocarcinoma. He was diagnosed to have stage C prostate cancer. A standard dose of luteinizing hormone-releasing hormone (LH-RH) analogue, leuprorelin acetate (3.75 mg), was administered every 4 weeks for 15 months. No adverse effects were observed throughout the period. The clinical response to LH-RH analogue was excellent, with normalization of serum prostate-specific antigen level and relief of dysuria. Thus the standard dosage of LH-RH analogue is considered to be adequate for hemodialysis patients.

Two major strains of type 1 wild poliovirus circulating in Indochina

Two hundred ninety-four isolates from 329 patients with acute flaccid paralysis in Cambodia and Vietnam during 1992-1995 were identified as type 1 wild polioviruses. Among these isolates, 85 were selected as geographic representatives and were examined by determining the nucleotide sequences of their genome in the VP1 region. The phylogenic analysis revealed that all of the isolates examined were classified into groups A and B. Isolates belonging to group A had been found only in northern Vietnam until 1993 but not in 1994 and 1995. Group B isolates were located in both northern and southern Vietnam and Cambodia. In 1994 and 1995, however, only group B isolates were found in the Mekong Delta area in southern Vietnam and Cambodia. Isolates of groups A and B were genetically different from strains previously isolated in other Asian countries. One of the two indigenous wild polioviruses still remains to be eliminated in this area.

[Wilms' tumor with marked calcification in an 8-year-old boy: a case report]

An 8-year-old boy presented with asymptomatic gross hematuria. Clinical investigation revealed an 8-cm left renal tumor accompanied with marked calcification. Radical nephrectomy with lymph node dissection was performed. Pathological diagnosis was Wilms' tumor without lymph node metastasis. He has been free of recurrence 20 months postoperatively. Our case features prominent calcification on radiological examination, which is uncommon in Wilms' tumor. We reviewed the literature on the relationship between renal tumors and calcification.

GTP cyclohydrolase I feedback regulatory protein is a pentamer of identical subunits. Purification, cDNA cloning, and bacterial expression

GTP cyclohydrolase I feedback regulatory protein (GFRP) mediates feedback inhibition of GTP cyclohydrolase I activity by tetrahydrobiopterin and also mediates the stimulatory effect of phenylalanine on the enzyme activity. To characterize the molecular structure of GFRP, we have purified it from rat liver using an efficient step of affinity chromatography and isolated cDNA clones, based on partial amino acid sequences of peptides derived from purified GFRP. Comparison between the amino acid sequence deduced from the cDNA and the N-terminal amino acid sequence of purified GFRP showed that the mature form of GFRP consists of 83 amino acid residues with a calculated Mr of 9,542. The isolated GFRP cDNA was expressed in Escherichia coli as a fusion protein with six consecutive histidine residues at its N terminus. The fusion protein was affinity-purified and digested with thrombin to remove the histidine tag. The resulting recombinant GFRP showed kinetic properties similar to those of GFRP purified from rat liver. Cross-linking experiments using dimethyl suberimidate indicated that GFRP was a pentamer of 52 kDa. Sedimentation equilibrium measurements confirmed the pentameric structure of GFRP by giving an average Mr of 49,734, which is 5 times the calculated molecular weight of the recombinant GFRP polypeptide. Based on the pentameric structure of GFRP, we have proposed a model for the quaternary structure of GFRP and GTP cyclohydrolase I complexes.

Dedifferentiated human ventricular cardiac myocytes express inducible nitric oxide synthase mRNA but not protein in response to IL-1, TNF, IFNgamma, and LPS

There is evidence that nitric oxide (NO) may mediate some of the functional myocardial changes caused by bacterial LPS and inflammatory cytokines. The expression of the inflammatory or inducible NO synthase (iNOS) in human cardiac myocytes, however, has not been well characterized. Therefore, we treated cultured, dedifferentiated human ventricular cardiac myocytes with the combination of TNF-alpha (500 U/ml), IL-1beta (30U/ml), IFNgamma (100 U/ml), and LPS (E.coli 0111:B4, 10 microg/ml). Northern blot analysis revealed a approximately 4.5 kb transcript for inducible NOS (iNOS) in the stimulated human heart cells but not in untreated cells. RT-PCR confirmed that iNOS mRNA was only present in stimulated cells. However, treatment of the myocytes for up to 96 h with cytokines and LPS did not result in NO synthesis as measured by nitrite + nitrate accumulation in the culture medium, and no iNOS enzymatic activity could be detected in the cell lysates. Western blot analysis failed to detect iNOS protein. Thus, despite high and persistent levels of iNOS mRNA in cytokine-treated cells, iNOS protein was absent in this experimental model. GTP-cyclohydrolase I was induced both at the mRNA and protein levels and resulted in increased biopterin levels, indicating sufficient amounts of the cofactor tetrahydrobiopterin (BH4) were present, and that the failure to express an inducible protein was specific to iNOS. To determine if the absence of iNOS protein was due to a novel cardiac iNOS gene or modified iNOS transcript in human myocytes, we cloned an iNOS cDNA from cytokine-treated myocytes. Sequencing and expression of the clone revealed a functional iNOS cDNA with >99% identity to other human iNOS cDNA clones. When human cardiac cells were transduced with a retroviral vector carrying only the coding region of the human hepatocyte iNOS cDNA, both iNOS mRNA and protein could be detected. In conclusion, these cells derived from cultured human cardiac myocytes lacked the capacity to express an endogenous iNOS protein, the basis of which appears to be a cell-specific suppression or failure of iNOS translation.

[Treatment of gingivitis in elderly patients in a nursing home]

For 3 months, 4 patients in a nursing home for the elderly received supervised professional oral care in conjunction with oral hygiene instruction. Within the first month after the start of this program, plaque was reduced to 1/3 and gingivitis was reduced to 1/9 of their respective initial levels. In 5 patients who did not receive either oral hygiene instruction or professional oral care, plaque retention and gingivitis were unchanged. We conclude that professional oral care combined with oral hygiene instruction supervised by dental professionals can help to control gingivitis in the elderly.

[Pharyngeal bacteria and professional oral health care in elderly people]

In 15 elderly residents of an old-age home, we measured the total number of bacteria and the numbers of streptococci and staphylococci in the pharynx over 5 months. Seven residents received professional oral health care from dentists and dental hygienists and eight practiced oral care by themselves or together with a helper. During the 5 months, the total number of bacteria and the numbers of streptococci and staphylococci decreased (p < 0.01) in those who received professional care. In contrast, the total number of bacteria and the numbers of streptococci and staphylococci neither did not change or increased in those who did not receive professional care. These findings show that professional oral health care by dentists and dental hygienists can decrease the total number of bacteria and the numbers of streptococci and staphylococci in the pharynx of elderly people, which might prevent aspiration pneumonia.

[Clinical evaluation of tandem PSA for the diagnosis and follow-up of prostate cancer]

The Tandem PSA test was performed simultaneously with assay of Markit-M PA and gamma-seminoprotein to determine its usefulness for the diagnosis of prostate cancer in a total of 81 patients with prostate diseases. The diagnosis was untreated prostate cancer in 16 patients including 2 with T1c tumor, benign prostatic hyperplasia in 56 patients, and other diseases in 9 patients. Tandem PSA, Markit-M PA, and gamma-seminoprotein showed a sensitivity of 81.3, 62.5, and 68.8%, respectively, while the specificity was 67.7, 81.5, and 72.3%, respectively. Tandem PSA had the highest sensitivity, although the specificity and accuracy were the lowest. These results were considered to be due to the fact that the PSA level becomes significantly higher with an increase in the weight of benign prostatic hyperplasia. This indicates that the PSA density should be considered to improve the specificity of Tandem PSA. Use of the Tandem PSA/gamma-seminoprotein ratio was also examined as a possible method which might improve the specificity. Patients with benign prostatic hyperplasia and prostate cancer had a ratio of 1.53 +/- 0.966 and 3.21 +/- 1.811 (mean plus standard deviation), respectively, and these 2 groups showed a significant difference (p = 0.0008). This indicates that calculation of the Tandem PSA/gamma-seminoprotein ratio may be useful to improve the specificity of Tandem PSA for the diagnosis of prostate cancer.

Circulation of type 1 wild poliovirus in northern Vietnam during 1991-1994

From 1991 to 1994, 143 polioviruses were isolated from patients with acute flaccid paralysis in northern Vietnam. Of these 143 isolates, 133 were type 1 and five of each were type 2 and type 3. These isolates were intratypically differentiated by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Of the 133 type 1 isolates, 113 were wild strains and only 20 isolates were of Sabin vaccine-like strains. These 113 isolates were divided into seven groups by PCR-RFLP patterns and were also classified into three genomic groups by nucleotide sequencing and phylogenetic analysis. One of the three genomic groups accounted for the majority (75) of these isolates. The isolates belonging to the predominant group were found during 1991-1993. The second group, which included 17 isolates, were detected only in 1993. These isolates had genome sequence similar to isolates in southern Vietnam in the same year. The third group of isolates were detected only in 1991 and were considered to be Mahoney-like wild strains. All isolates examined were different from those obtained in other countries. In 1994, however, no wild-type polioviruses were isolated in our study. These results reveal that three unique strains were circulating in northern Vietnam in recent years, and indicate that the incidence of poliomyelitis due to wild poliovirus is decreasing.

Competition for tetrahydrobiopterin between phenylalanine hydroxylase and nitric oxide synthase in rat liver

Tetrahydrobiopterin (BH4) is an important cofactor for two hepatic enzymes, inducible nitric oxide synthase (iNOS) and phenylalanine hydroxylase (PAH), and competition for BH4 between the two enzymes might limit hepatic iNOS or PAH activity. To test this hypothesis, we determined whether conversion of phenylalanine to tyrosine was modified by changes in NO synthase activity, and conversely whether NO synthesis was limited by the rate of phenylalanine conversion to tyrosine in rat hepatocytes and perfused livers. NO production was decreased only slightly, when flux through PAH was maximized in isolated perfused livers, and in isolated hepatocytes only when BH4 synthesis was inhibited. Increases in NO synthesis did not reduce tyrosine formation from phenylalanine. Phenylalanine markedly increased biopterin synthesis, whereas arginine had no effect. Thus, basal BH4 synthesis appears to be adequate to support iNOS activity, whereas BH4 synthesis is increased to support PAH activity.

[Clinical analysis of 169 patients with prostate cancer]

At Matsumoto National Hospital, 169 patients with prostate cancer were diagnosed between April 1986 and May 1994. The prostate cancer incidence was the highest in the latter half of the seventies, with an average age of 74.3 years. The clinical stage was defined as A1, A2, B, C, and D2 in 24 (14.2%), 38 (22.5%), 39 (23.1%), 23 (13.6%) and 45 (26.6%) patients, respectively. The clinical stage was not correlated with the patient's age. Incidental carcinoma was discovered in 5.8% of the patients who underwent prostatectomy for benign prostatic hypertrophy (BPH). At initial diagnosis, the tumor was well, moderately, and poorly differentiated adenocarcinoma in 71 (42.0%), 64 (37.9%), and 34 (20.1%) patients, respectively. The median follow-up period was 38.7 months. The over all five-year crude survival rate was 54.8%, while the cause-specific five-year survival rate was 80.0%. The five-year crude survival rate was 58.4, 82.0, 55.2, 42.5 and 37.4%, for patients with cancer at stage A1, A2, B, C, and D. The survival rate was higher for patients with cancer at clinical stage A and shorter for those with cancer at clinical stage D than in other stages. Prognosis was also worse in patients with moderately or poorly differentiated adenocarcinoma than in those with well-differentiated adenocarcinoma. The clinical stage and the pathological grade are important as prognostic factors, although the high incidence of death from other diseases shows that the patients' age should be considered to choose the modality of therapy. These findings indicate that intensive treatment of the patients in clinical stage A2, B and C prostate cancer in combination with screening for the men between 50 and 75 years old for early cancer detection is required.

Vascular inducible nitric oxide synthase gene therapy: requirement for guanosine triphosphate cyclohydrolase I

BACKGROUND

Human inducible nitric oxide synthase (iNOS) gene transfer inhibits myointimal hyperplasia in vitro. However, unstimulated vascular smooth muscle cells (SMC) do not synthesize tetrahydrobiopterin (BH4), an essential cofactor for iNOS, which may be an obstacle to successful vascular iNOS gene therapy. We investigated the capacity of gene transfer of guanosine triphosphate (GTP) cyclohydrolase I (GTPCH), the rate-limiting enzyme for BH4 biosynthesis, to supply cofactor for iNOS activity.

METHODS

A human GTPCH expression plasmid (pCIS-GTPCH) was transfected into rat aortic SMC (RAOSMC) and BH4-deficient NIH3T3 cells engineered to stably express human iNOS (3T3-iNOS). GTPCH activity and intracellular biopterins were assessed as a measure of successful transfection, and the capacity of GTPCH to reconstitute iNOS activity was used to determine whether BH4 was made available to the iNOS protein.

RESULTS

The pCIS-GTPCH-transfected 3T3 cells had demonstrable GTPCH activity as compared with control cells (169.3 +/- 6.6 pmol/hr/mg versus 0, p < 0.001). Intracellular biopterin levels were also increased in transfected 3T3 and SMC (60.6 +/- 2.6 and 101.7 +/- 28.3 pmol/mg, respectively, versus less than 4 in control cells). GTPCH reconstituted near-maximal iNOS activity in 3T3-iNOS cells despite a gene transfer efficiency of less than 1%. GTPCH and iNOS enzymes did not have to coexist in the same cell for the synthesized BH4 to support iNOS activity.

CONCLUSION

GTPCH gene transfer reconstitutes iNOS activity in BH4-deficient cells despite poor transfer efficiency. GTPCH can deliver a cofactor to targeted cells even if it is synthesized in neighboring cells, and may be a means to concurrently deliver BH4 with iNOS in vivo.

[Bowel anastomosis using valtrac in urologic surgery]

Valtrac, a biofragmentable anastomosis ring, was used in 10 patients who underwent total cystectomy and urinary tract reconstruction. The primary disease was bladder tumor, neurogenic bladder, and sigmoid colon cancer invading the bladder in 8, 1, and 1 of the patients, respectively. There were 8 ileo-ileostomies and 2 ileo-colostomies. No patient developed anastomotic leakage or insufficiency. Symptoms of mild bowel obstruction were observed in 3 patients, but they improved with conservative management. The outcome was good in all the patients without further ileus during a follow-up period of 1 to 12 months (median: 7.3 months). The most important advantage of this device is that precise bowel anastomosis is standardized and can be achieved safely and quickly. Our findings indicate that the Valtrac system offers a reliable and reproducible alternative to conventional anastomotic techniques in urologic surgery.

Genetic basis of the neurovirulence of type 1 polioviruses isolated from vaccine-associated paralytic patients

We examined four type 1 polioviruses isolated from the stools of patients with vaccine-associated paralytic poliomyelitis in China. All of these isolates were shown to be Sabin derived viruses by restriction fragment length polymorphism assay after polymerase chain reaction and by sequencing of the viral genome encoding the viral coat protein, VP1. However, the same analysis of the 3D coding region suggested that two of the four isolates had the sequence of wild type poliovirus in the tested region. Furthermore there were also point mutations in the 5' non-coding region. One was a single base change from U to C at nucleotide position 525, and the other three were from G to A at position 480. All the four strains were more neurovirulent that Sabin type 1 virus in transgenic mice with human poliovirus receptor gene. The data showed that the nucleotide positions of type 1 poliovirus which were identified to be in favor of the high neurovirulence were indeed changed during natural transmission, and suggested that the point mutation alone or a recombination of the vaccine type with wild type genome results in an acquisition of neurovirulence.

[A clinical and pathological study of radical prostatectomy for prostate cancer]

BACKGROUND

Thirty-one patients with prostate cancer underwent radical prostatectomy and simultaneous pelvic lymphadenectomy at Matsumoto National Hospital between 1988 and 1994. Prognostic factors are discussed from their clincopathological findings.

METHODS

The patients ranged from 54 to 80-year-old, with an average age of 69.9 years. The median follow-up period was 44 months. The diagnosis was confirmed by needle biopsy or transurethral resection of the prostate. All the patients received short-term endocrine therapy preoperatively, and only noncuratively resected patients underwent adjuvant therapy postoperatively. At initial diagnosis, the tumor grades were well, moderately, and poorly differentiated adenocarcinoma in 9, 12, and 10 patients, respectively. The clinical stage was defined as A2, B, C, D1, and D2 in 12, 4, 6, 3, and 6 patients, respectively.

RESULTS

A difference of tumor grade was found between the initial diagnosis and the final diagnosis based on the resected prostate in 8 patients (26%), with 7 of them (88%) showing an increase in grade in the final diagnosis. Also revealed was that 11 of the 25 patients (44%) in stage A2, B, C, or D1 had been understaged preoperatively. The five-year actuarial survival rates were 100%, 92%, and 51% for patients with well, moderately, and poorly differentiated adenocarcinoma, respectively, with a significant difference noted between well and poorly differentiated adenocarcinoma (p = 0.03). Recurrence only developed in patients with pathological stage D tumors. However, the presence or absence of lymph node metastasis did not affect the crude 5-year survival rate. Several stage D patients were successfully treated by radical prostatectomy and adjuvant therapy, achieving long survival.

CONCLUSION

These results indicate that patients in clinical stage C have tumors which exhibit differing biological behavior. These patients should be analyzed and classified more precisely so that the most appropriate therapy can be chosen.

Significance of the chromatin structure in expression of the rat prolactin gene

To elucidate the mechanisms underlying cell type-specific expression of the growth hormone (GH) and prolactin (PRL) genes, we used rat pituitary-derived cell lines producing exclusively GH (GC cells) or PRL (235 cells), and examined the following: expression of transcription factors essential for GH and/or PRL gene expression; promoter/enhancer activity of the GH and PRL genes transiently introduced by transfection; and chromatin structures of the GH and PRL genes. Even in PRL-nonproducing GC cells, the PRL promoter/enhancer was more active than the GH promoter, and the transcription factors, Pit-1 and estrogen receptor (ER), essential for PRL gene expression were functional. The PRL promoter/enhancer of GC cells was normal. On DNase I sensitivity analysis of the chromatin structure, two hypersensitive sites were detected in PRL gene chromatin of PRL-producing 235 cells but none in that of GC cells. It thus follows that the major reason for absence of the expression of the endogenous PRL gene in GC cells is neither the lack of transcription factors necessary for PRL gene expression nor an anomaly of the PRL gene itself, but that the chromatin structure of the PRL gene differs in PRL-nonproducing and -producing cells. It was shown in this study that neither Pit-1 nor ER is required for conversion of the structure of PRL gene chromatin to a DNase I-hypersensitive state.