Protective effect of ceftriaxone against the nephrotoxicity of isepamicin administered once daily in rats

The protective effect of ceftriaxone on isepamicin-induced nephrotoxicity was investigated. For 14 d, Wistar rats were administered either ceftriaxone 100 mg/kg intraperitoneally, isepamicin 300 mg/kg subcutaneously, or ceftriaxone isepamicin in combination. The animals given 300 mg/kg of isepamicin showed a significant increase in urine NAG (N-acetyl-beta-D-glucosaminidase) levels as compared with the control animals which received saline (p<0.01). However, the increase in NAG level was markedly less when isepamicin was administered in combination with ceftriaxone (p<0.01). Ceftriaxone alone had no effect on urine NAG activity. Serum creatinine levels were significantly higher in animals treated with isepamicin alone than in control animals (p<0.01) or animals receiving the isepamicin ceftriaxone combination (p<0.01). After 14 d of treatment, ceftriaxone had not accumulated in renal tissue, but it did reduce the renal intracortical accumulation of isepamicin (p<0.01). Histopathologically, ceftriaxone induced very few cellular alterations and considerably reduced the manifestation of typical signs of isepamicin nephrotoxicity. This investigation demonstrates that ceftriaxone protects animals against isepamicin-induced nephrotoxicity.

Characterization of the subsite structure of the beta-glucosidase from Aspergillus niger, an aspect of the mechanism of carbohydrate recognition

Steady-state kinetics on the reaction catalyzed by the beta-glucosidase of Aspergillus niger were carried out to evaluate the kinetic parameters, Km and ko, for phenyl beta-D-glucosides. The ko/Km values, which may relate to productive binding at subsites, were found to correlate with the substituent constant pi (hydrophobicity), suggesting that subsite 2 has a hydrophobic character. A "hydrophobic-driven" mechanism is considered to contribute to the productive E-S complex for recognition of the substrate.

[Imaging studies of excretory urography and computed tomography scan for patients suffering from renal colic]

Renal colic mainly due to urolithiasis is one of the most common morbid conditions in urology and commonly seen in the urology emergency clinic. Imaging studies were performed to evaluate the upper urinary tract of 29 patients suffering from renal colic in the 2 years between November, 1994 and October, 1996. After intramuscular injection of the analgesic (pentazocine, 15 mg), all 29 patients were examined by excretory urography (IVP) at the time of the first visit. In some patients abdominal plain computed tomography (CT) scan was performed consecutively even when extravasation of the contrast medium was not seen. Spontaneous peripelvic extravasation was seen in 14 patients (11 males and 3 females) with urolithiasis; 7 of them were diagnosed by IVP, 5 by IVP plus CT scan and 2 with CT scan only. IVP imaging study followed by plain abdominal CT scan is useful even when the contrast medium is not extravasated on IVP in patients suffering from renal colic.

Developmental changes in the NGF content in the brain of young, growing, low-birth-weight rats

The NGF content in each region of the brain of four-week-old rats was ranked in the decreasing order of cerebral cortex, hippocampus, cerebellum, midbrain/diencephalon, and pons/medulla oblongata, and the NGF concentration, in the decreasing order of hippocampus, cerebral cortex, cerebellum, midbrain/diencephalon, and pons/medulla oblongata in both AFD and SFD groups. The NGF content and concentration in the cerebral cortex were about the same value at each age between those in the AFD and SFD groups. Those in the hippocampus were a little higher in the SFD group than in the AFD group at the ages of three and four weeks, unlike those in the other regions, where the values for the cerebellum, midbrain/diencephalon and pons/medulla oblongata tended to be somewhat higher in the AFD group than in the SFD group. The NGF concentrations in the hippocampus and cerebral cortex increased with growth: the concentration in the hippocampus at four weeks of age was about 4-fold of that at one week in the AFD group and about 5.7-fold of that at one week in the SFD group; and likewise the concentration in the cerebral cortex at four weeks of age was about 5.3-fold in the AFD group and about 7-fold in the SFD group. The NGF concentrations in the cerebellum decreased, and those in midbrain/diencephalon and pons/medulla oblongata hardly changed with growth in either AFD or SFD group. From these results NGF may have stronger implications for the neuronal growth in the hippocampus compared with those in the lower brain regions of the SFD rats.

Immunohistochemical studies of proliferating cell nuclear antigen and cathepsin D in transitional cell carcinoma of the urinary bladder

Immunohistochemical staining for proliferating cell nuclear antigen (PCNA) and cathepsin D was performed on 60 transitional cell carcinoma (TCC) specimens from 60 patients with bladder cancer. The percentage of PCNA-positive cells (PCNA-labelling index) was determined by counting 500 or 1,000 cells, and cathepsin D expression was graded according to the extent of immunoreactivity to anti-cathepsin D antibody. The PCNA-labelling index was significantly higher in high-grade and high-stage tumors compared to that in low-grade and low-stage tumors. Cathepsin D was highly positive in grade-1 tumors. In contrast, 82% of grade-3 tumors and 76% of advanced tumors showed negative or low reactivity to anti-cathepsin D. Groups of high PCNA-labelling index and negative cathepsin D had significantly poorer prognoses compared to those of the low PCNA group and cathepsin D highly positive group, respectively, in univariate analyses. However, neither of these two factors were independent prognostic factors in multivariate analyses. These results suggest that the PCNA-labelling index and cathepsin D expression may indicate the malignant potential of TCC and may be able to provide additional information for predicting survival when stratifying for grade of bladder cancer.

Multiple isoforms of neuregulin are expressed in developing rat dorsal root ganglia

Accumulating evidence suggests that neuregulin (NRG) plays special roles in the development of the mammalian nervous system. We have already identified NRG as a survival factor for Schwann cells during development. In this report, we have studied all possible NRG isoforms and expression of NRG in the developing rat dorsal root ganglia (DRG) and compared them with those of brain and spinal cord. Neural NRG isoforms comprise common immunoglobulin and epidermal growth factor domains. Various different transcripts were characterized, which arose by alternative splicing in several regions: N-terminal (exon 1 or 2), spacer (exon 5), juxtamembrane (exon 9 or 10), and cytoplasmic (exon 12, 13, or 14) domains. At least 13 novel isoforms among 16 splice variants were identified. The transmembrane isoforms of NRG are dominant forms in developing rat DRG. The mRNA expression of NRG isoforms in DRG is similar to that in spinal cord, while in brain the expression is much less. The mRNA in DRG was found at similar levels from birth to postnatal day 7 of the premyelinating stage, and it decreased afterward. Our results suggest that several NRGs, including isoforms not reported before, play a role as survival factors for Schwann cells in the premyelinating stage.

Subsite structure of the beta-glucosidase from Aspergillus niger, evaluated by steady-state kinetics with cello-oligosaccharides as substrates

The beta-glucosidase from a commercially available preparation from Aspergillus niger was highly purified. The Michaelis constant Km and the molar activity K0 for cello-oligosaccharide substrates Gn (n = 2-6) were obtained by steady-state kinetic analysis on the beta-glucosidase-catalyzed hydrolysis at 25 degrees C and pH 5.0. Stoichiometric production of Gn-1 by the beta-glucosidase reaction for Gn was confirmed by HPLC techniques. Based on Km and K0 for Gn, subsite affinities (Ai, i = 1-6) were estimated as follows (kcal/mol): A1 = 1.3, A2 = 5.2, A3 = 0.65, A4 = -0.10, A5 = -0.65, and A6 = -0.26, of which A1-A3 are much higher than those of the beta-glucosidase of Candida wickerhamii. The subsite structure is quite similar to that of the alpha-glucosidase of A. niger, whereas the dependence of k0 on n is highly characteristic for beta-glucosidase, and decreases with n, suggesting some interaction between the particular subsites.

Expression of L1 in primary astrocytes via a defective herpes simplex virus vector promotes neurite outgrowth and neural cell migration

The neural cell adhesion molecule L1 is a transmembrane glycoprotein of approximately 200 kDa molecular weight that is a member of the immunoglobulin super family. Multiple functions of L1 have been reported, including cell-cell interactions, neurite elongation, axonal fasciculation, cell migration, and myelination. L1 plays important roles in neural development and axonal regeneration in the peripheral nervous system (PNS), however, in the adult it is only present on neurons in the central nervous system (CNS). In the present study we have used defective herpes simplex virus (HSV) vectors to express full-length human or rat L1 in cultured primary rat cortical astrocytes. Rat cerebellar granule cells, a rather homogeneous population of neurons, co-cultured on a substrate layer of L1-expressing astrocytes demonstrated increased migration and neurite extension compared with neurons co-cultured on lacZ-expressing astrocytes of uninfected astrocytes. There was no detectable difference between human and rat L1. Because this vector system can be used to confer phenotypic changes in primary nervous system cells it will be useful for in vitro and in vivo studies of neural regenerative sprouting and plasticity in the CNS.

Gene therapy: targeting tumor cells for destruction

Human gene therapy involves the transfer of genetic material into cells of a patient, either in vitro or in situ, for the therapeutic purpose of correcting or ameliorating genetic defects, alleviating disease, inhibiting infectious agents or destroying cancer cells. After identification of an appropriate disease target (inherited or acquired) for treatment, a number of basic technical issues underlie any gene therapy strategy. These include the choice of genetic material to be transferred, target cell or organ for gene modification, delivery systems and representative animal models of the targeted human disease. Tumor gene therapy represents a somewhat special category for gene therapy because its intended goal is the destruction of tissue rather than its correction or preservation. For an experimental therapeutic, cancer represents a useful target due to the paucity of effective treatments and the terminal nature of the disease. Viral vectors, currently the most widely used agents for gene delivery, generally fall into two classes; defective, which are unable to replicate; and replication-competent, which are able to replicate and spread within defined cell types. The strategies employed for cancer gene therapy range from cytotoxicity, either direct or through a 'suicide' gene-producing, to induction of a host antitumor immune response. Gene therapy is rapidly moving into the clinic, yet its efficacy remains to be demonstrated. Research into the underlying fundamentals of gene therapy discussed in this review will be critical to the ultimate success of this therapeutic modality.

Dose-dependent effects of oral acyclovir in the incubation period of varicella

Dose of acyclovir (ACV) and clinical features of varicella were evaluated in 65 household contacts (0.8-9 y) who received oral ACV (5-80 mg/kg daily in four divided doses) during the latter half of the incubation period of varicella. The severity of the disease was compared with that of 23 children who did not receive ACV. Infection was confirmed by a fluorescent antibody to membrane antigen assay. The antibody titers and the rate of apparent infection increased as the dose of ACV administered decreased. The number of skin lesions in patients who received ACV was significantly reduced when compared to the control group. These data suggest dose-dependence of ACV for modification of varicella during secondary viremia in the incubation of the disease.

[Cell adhesion proteins in the nervous system: immunoglobulin superfamily--structure, function and involvement in neurological diseases]

Cell adhesion proteins play important roles in cell-cell interactions, which regulate development and maintenance of multicellular organisms. In the nervous system, there exist unique groups of cell adhesion proteins, that are essential for elaborate neural network formation. Accumulated evidences indicate these proteins express and function at spatially and temporally defined stages of development and regeneration of the nervous system. Recent studies revealed that some mutations of cell adhesion proteins cause various neurological diseases. In this article, we review recent progress and perspectives of studies on proteins of immunoglobulin superfamily in the nervous system, focusing on their structure, physiological roles and involvement in neurological diseases.

Treatment of glioblastoma U-87 by systemic administration of an antisense protein kinase C-alpha phosphorothioate oligodeoxynucleotide

Glioblastoma multiforme is the most common form of malignant brain cancer in adults and, unfortunately, is not amenable to treatment with current therapeutic modalities. Human glioblastoma U-87 has many of the distinguishing phenotypic features of primary glioblastoma, including an autocrine form of proliferation, high levels of protein kinase C alpha (PKC alpha), and infiltration via white matter tracts. We show that treatment of mice bearing U-87 xenografts with an antisense phosphorothioate oligodeoxynucleotide (S-oligodeoxynucleotide) against the 3'-untranslated region of PKC alpha mRNA results in suppression of tumor growth. Growth was inhibited in both subcutaneous and intracranial tumors, and in the latter instance, treatment with the antisense PKC alpha S-oligodeoxynucleotide resulted in a doubling in median survival time ( > 80 days), with 40% long term survivors. The antisense S-oligodeoxynucleotide did not produce systemic toxicity in mice with subcutaneous or intracranial tumors after daily intraperitoneal injection for 21 or 80 days, respectively, and a scrambled S-oligodeoxynucleotide with the same nucleotide composition as the antisense S-oligodeoxynucleotide did not produce an antitumor effect. The intratumoral levels of both antisense and scrambled S-oligodeoxynucleotide in subcutaneous tumors were 2 microM after 21 daily doses of 20 mg/kg S-oligodeoxynucleotide. The antisense S-oligodeoxynucleotide selectively reduced the levels of PKC alpha in subcutaneous tumors but not those of protein kinase C epsilon or protein kinase C zeta. This is the first demonstration that the growth of glioblastoma multiforme can be suppressed by an antisense PKC alpha S-oligodeoxynucleotide and suggests that this may represent an effective therapy for this type of malignancy.

[Emphysematous cystitis: a case report]

Emphysematous cystitis is a rare condition in which gas-forming organisms produce gas in the bladder wall and lumen. We present a case of emphysematous cystitis with neurogenic bladder. The patient was a 78-year-old man who complained of dysuria and lower abdominal soft mass. Urine culture yielded Klebsiella pneumoniae and Enterococcus faecalis. A plain X-ray film of upright position showed a large air-fluid level. The gas was demonstrated in the bladder wall and lumen on CT scan. These findings were compatible with that of emphysematous cystitis. The symptoms were improved and the intraluminal gas had disappeared on radiography after treatment with antibiotics. We reviewed 20 cases of emphysematous cystitis reported in the Japanese literature and reported clinical characteristics of 21 patients including ours here.

Yearly variation of spontaneous somatic mutation frequency in the stamen hairs of Tradescantia clone KU 9 grown outdoors, which showed a significant increase after the Chernobyl accident

Scoring of spontaneous somatic pink mutation frequency in the stamen hairs of Tradescantia clone KU 9, a heterozygote for flower color (blue/pink; the blue color being dominant), was carried out for 11 years on plants grown outdoors, during the period of May 11-31 (for 3 weeks) in every year from 1982 to 1992. Weekly and yearly variations of the spontaneous mutation frequency were observed, and such variations could mostly be correlated to the difference in temperature. That is, the mutation frequency was generally higher in the weeks and years when the temperature was relatively low, showing the strongest negative correlation with the average minimum temperature. The variations were also correlated to the diurnal temperature difference, the mutation frequency being higher with larger diurnal temperature difference in general. However, the mutation frequency observed in 1986 was exceptionally higher than that expected from the temperature for this year, and was very significantly higher than for other years. The scoring of mutation frequency was thus continued in 1986 for an additional 4 weeks (June 1-28), and it was confirmed that such higher mutation frequencies lasted for 6 weeks in total. The exceptionally high mutation frequency seemed to be related to the radioactive fallout which occurred in early to mid May of 1986, even in Japan, after the serious nuclear reactor accident at Chernobyl, and also to the biological concentrations of radioactive nuclides which subsequently occurred, although it was difficult to conclude this definitely. The mutation frequency in 1987 was second highest, and was also significantly higher than the lowest mutation frequency observed in 1990.

Cell-adhesion proteins of the immunoglobulin superfamily in the nervous system

The unique groups of cell-adhesion proteins, such as IgSF, play essential parts in the formation and maintenance of the nervous system. Recent crystallographic studies have revealed a possible common structure of cell-adhesion proteins. The IgSF proteins are sub-grouped into simple, complex and mixed types. Accumulating evidence reveals the importance of cell-adhesion proteins in neural morphogenesis, maintenance and regeneration. They play key roles in neuronal migration, neurite outgrowth promotion, neurite fasciculation, pathfinding, target recognition, synaptogenesis and myelination. Mutations of cell-adhesion proteins result in neurological disease; for example, mutations of PO in hereditary neuropathy and mutations of L1 in hereditary hydrocephalus, MASA syndrome and spastic paraplegia type 1. Perspectives of the studies of neural cell-adhesion proteins are discussed.

Treatment of human malignant meningiomas by G207, a replication-competent multimutated herpes simplex virus 1

We have demonstrated that replication-competent attenuated mutants of herpes simplex virus type 1 (HSV-1) have therapeutic potential for malignant gliomas. Moreover, a recently described multiple mutant HSV (termed G207) has properties which may allow human clinical trials. G207 is able to replicate within and kill cells from three human malignant meningiomas in cell culture. In nude mice harboring s.c. human malignant meningioma (F5), G207 can inhibit growth in a dose-dependent fashion. In nude mice harboring intracranial subdural human malignant meningioma (F5), one injection of G207 caused significantly decreased tumor growth and one apparent cure with neither neurological dysfunction nor pathological changes in the surrounding brain. These results suggest that G207 should be considered for therapeutic trials in the treatment of malignant meningioma refractory to currently available therapies.

Attenuated multi-mutated herpes simplex virus-1 for the treatment of malignant gliomas

We have created a double mutant of the herpes simplex virus (HSV) type 1 (termed G207) with favourable properties for treating human malignant brain tumours: replication-competence in glioblastoma cells (and other dividing cells), attenuated neurovirulence, temperature sensitivity, ganciclovir hypersensitivity, and the presence of an easily detectable histochemical marker. G207 has deletions at both gamma 34.5 (RL1) loci and a lacZ gene insertion inactivating the ICP6 gene (UL39). G207 kills human glioma cells in monolayer cultures. In nude mice harbouring subcutaneous or intracerebral U-87MG gliomas, intraneoplastic inoculation with G207 causes decreased tumour growth and/or prolonged survival. G207 is avirulent upon intracerebral inoculation of mice and HSV-sensitive non-human primates. These results suggest that G207 should be considered for clinical evaluation in the treatment of glioblastomas.

Decrease of NCAM expression and astrocyte-neurone interaction in long-term cultured astrocytes

In order to assess the characteristics of the older astrocyte, we obtained long-term cultured rat astrocytes (20 months) and examined the features of protein expression in relation to neuronal interaction. In short-term cultured astrocytes, NCAM expressed strongly in contrast to weak expression of laminin by both immunocytochemical and ELISA assay. On the contrary, in long-term cultured astrocytes, a marked decrease of NCAM expression was observed along with increased laminin expression compared with short-term cultured astrocytes. The long-term cultured astrocytes remained positive to anti-GFAP antibody and showed a much lower ability to interact with neurones than the short-term cultured astrocytes. NCAM may be one of the responsible molecules related to the astrocyte-neurone interaction in the developing and ageing nervous system.

Detection of human herpesvirus 6 DNAs in samples from several body sites of patients with exanthem subitum and their mothers by polymerase chain reaction assay

Polymerase chain reaction amplification was used to detect human herpesvirus 6 (HHV-6) DNAs in peripheral blood mononuclear cells (MNCs), plasma, saliva, stool, and urine from three patients with exanthem subitum and in peripheral blood MNCs, plasma, and saliva from their mothers. HHV-6 DNAs were detected in MNCs during and after the disease and were found in plasma only in the acute phase. The virus DNAs were also detected in saliva after recovery from the illness and were found persistently or intermittently in stool but not in urine samples after the onset of the disease. In contrast, one of the three mothers excreted HHV-6 DNAs persistently in saliva. None of the mothers had the virus DNAs in peripheral blood MNCs and plasma nor a significant increase in antibody titers to HHV-6 after possible exposure from their children. These findings suggest systemic replication of HHV-6 during the acute phase in patients with exanthem subitum and persistent infection of the virus in several organs after recovery from the disease.

Clinical features and viral excretion in an infant with primary human herpesvirus 7 infection

OBJECTIVE

To find clinical features of a virologically-confirmed patient with primary human herpesvirus 7 (HHV-7) infection and a relationship of the excretion of viruses between HHV-7 and human herpes-virus 6 (HHV-6).

PATIENT AND METHODS

A 13-month-old boy who had a known prior history of exanthem subitum at 6 months of age developed fever for 3 days and a skin rash appeared as the fever was resolving. The course was accompanying with nonspecific signs and symptoms such as anorexia, irritability, mild diarrhea, palpebral edema, mild inflammation of pharynx, and mild occipital and cervical lymphadenopathy. Heparinized blood samples were used for isolation of HHV-6 and HHV-7 and detection of both virus DNA sequences by a nested polymerase chain reaction (PCR) amplification. Samples from other body sites were also tested for their DNA sequences using the PCR. Both virus antibody activity was measured by an indirect immunofluorescent assay or a neutralization test.

RESULTS

Cultured mononuclear cells from the patient at the acute stage of the disease produced morphologic changes, which reacted only with the monoclonal antibody to HHV-7 but not with the antibody to HHV-6. Both viruses were not isolated from blood obtained at the convalescent stage. An antibody response of the patient indicated a seroconversion to HHV-7 but not to other microbial agents including HHV-6 and Mycoplasma pneumoniae. Both virus DNA sequences were detected in peripheral blood mononuclear cells at acute and convalescent stages. HHV-7 DNA was excreted into saliva and transiently into stool at an early convalescent stage followed by HHV-6 excretion into saliva. No HHV-7 and HHV-6 was excreted into urine.

CONCLUSIONS

Clinical features of a virologically confirmed patient with primary HHV-7 infection were comparable with those of primary HHV-6 infection and HHV-7 infection may reactivate HHV-6.

Inhibition of angiogenesis and growth of human non-malignant and malignant meningiomas by TNP-470

Meningiomas are relatively common (22%) vascular brain tumors. 3-11% of meningiomas are malignant, and defy currently available therapy. Inhibition of neovascularization is one potential strategy for treating these hypervascular tumors. Inhibition of tumor-induced angiogenesis by TNP-470 (previously termed AGM-1470), a synthetic analogue of fumagillin, was tested on the growth of human non-malignant and malignant meningiomas in nude mice. TNP-470 significantly inhibited tumor neovascularization and tumor growth of both non-malignant and malignant meningiomas. TNP-470 is now in human trial and should be tested for efficacy in treating malignant or recurrent aggressive meningiomas.

Plasmacytoma of the testis

Extramedullary plasmacytomas of the testes are extremely rare tumors, especially when occurring in the absence of precocious or concurrent diagnosis of multiple myeloma. This is a case report of an 83-year-old man with a solitary plasmacytoma of the left testis. Immunoperoxidase studies, performed on histologic specimens after radical orchiectomy, showed a monoclonal staining of intracellular immunoglobulin for IgG-lambda type. He has been well for more than 14 months with no evidence of local recurrence or multiple myeloma.

[Inferior vena caval tumor thrombus in a patient with renal angiomyolipoma associated with tuberous sclerosis]

A 34-year-old woman with tuberous sclerosis presented with an increase of an abdominal mass and intermittent left flank pain on May 20, 1991. Computed tomography showed multiple bilateral renal masses with fatty density areas and a fatty density thrombus in the inferior vena cava, which extended through the right renal vein of the right kidney on ultrasonography. The inferior vena caval thrombus was also demonstrated by magnetic resonance imaging. Since marked deterioration of the right renal function was found on renography, right radical nephrectomy with thrombectomy was performed on July 2. Microscopically all tumors were identical with angiomyolipoma. She was discharged on Jury 20 and had been followed with good renal function at the outpatient clinic for more than 2 years. Follow up CT revealed no interval changes in the left renal masses.