Cytotoxic glycosides from Albizia julibrissin

During the course of a study of leguminous plants, cytotoxicity was demonstrated by the crude saponin fraction of Albizia julibrissin. Following chromatographic purification, the structures of three novel saponins, julibrosides I-III (1-3), inclusive of a cytotoxic principle, were elucidated. A comparison of the cytotoxicity of julibrosides (1-3) and their prosapogenins (4-15) prepared by alkaline hydrolysis clearly indicated that both an alpha-L-arabinofuranosyl-(1-->4)-[beta-D-glucopyranosyl-(1-->3)]-alpha- L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl ester unit and a monoterpene-quinovopyranosyl moiety are crucial substituents for cytotoxicity among this class of compounds. The hydroxy group at C-16 of aglycon may play an important role in mediating cytotoxicity, and the N-acetyl-glucosamine moiety at C-3 seems to enhance activity because 3 showed the strongest cytotoxicity.

Melanin-concentrating hormone acutely stimulates feeding, but chronic administration has no effect on body weight

Melanin-concentrating hormone (MCH) has recently been proposed as both a central stimulator and an inhibitor of food intake. To clarify its role, we investigated the effects of MCH and the prepro-MCH-derived peptide neuropeptide E-I injected intracerebroventricularly (icv) in rats. MCH (0.15-15 micrograms) was injected icv at the beginning of the light phase. Food intake at 2 h showed a dose-dependent increase from 325 +/- 7% of the control value (1.5-microgram dose; P < 0.05) to 462 +/- 30% of the control value (15-microgram dose; P < 0.005). When 10 ng, 100 ng, and 5 micrograms MCH were injected icv at the beginning of the dark phase, only 5 micrograms stimulated feeding (166 +/- 16% of the control value; P < 0.05). At no dose did MCH inhibit feeding. Twice daily icv injections of MCH (5 micrograms) caused an average 197 +/- 9% increase in 2-h food intake for the first 5 days. Injections from days 6-8 did not stimulate feeding. Food intake and body weight at 24 h remained unchanged. Intracerebroventricular neuropeptide E-I had no effect on food intake alone and did not alter MCH-induced feeding. These studies show a dose-dependent stimulation of feeding by acute central administration of MCH. Tolerance is seen with chronic administration. These findings support a role for MCH in the immediate regulation of food intake, but not in body weight control.

High frequency of p53 protein expression in thymic carcinoma but not in thymoma

Thymic epithelial tumours are broadly classified into thymomas and thymic carcinomas. Although both tumours occasionally show invasive growth, they exhibit different clinical and biological findings. The oncogene and anti-oncogene in thymic epithelial tumours have not been evaluated fully. We investigated the expression of p53 protein by immunohistochemical analysis using the anti-p53 polyclonal antibody (CM-1) in 17 thymomas and 19 thymic carcinomas. We also examined p53 gene (exon 5-8) mutation in 18 thymic carcinomas by using polymerase chain reaction-single-strand conformation polymorphism methods and direct sequencing. Of the thymoma cases, only one invasive thymoma showed focal nuclear staining. Fourteen of the 19 thymic carcinomas (74%) showed nuclear staining. Point mutations of the p53 gene were recognized in only 2 of the 18 thymic carcinomas (11%). One was the mutation C to T transition in the first letter of codon 222 in exon 6, which results in the amino acid substitution from proline to serine. Another was a silent mutation. p53 protein accumulation is highly frequent in thymic carcinomas but not in thymomas, and gene mutation is uncommon in thymic carcinomas.

Neuroprotective effect of 4'-(4-methylphenyl)-2,2':6',2-terpyridine trihydrochloride, a novel inducer of nerve growth factor

We have identified 4'-(4-methylphenyl)-2,2':6',2-terpyridine: trihydrochloride (SS701), which belongs to a family of a small unique neuroprotective agents. SS701 accelerated the production of nerve growth factor (NGF) in cultured astroglial cells, dose- and time-dependently. In in vivo studies, SS701, when administered 30 min after induced cerebral ischemia, neuroprotective effects on delayed neuronal death in Mongolian gerbils were evident. The neuroprotective effects of SS701 against ischemia-induced delayed neuronal death are attributed to stimulation of the production of NGF.

Short-latency somatosensory evoked potentials in patients with cervical compressive lesions: morphological versus functional examination

We studied short-latency somatosensory evoked potentials (SSEPs) elicited by upper limb stimulation in 40 patients with cervical compressive lesions. Of these, 17 underwent MRI examination and the remaining 23 had myelography for the assessment of structural changes. The latencies of N11 and N13 recorded from the neck and P14 derived from the scalp were used to calculate the interpeak latencies from the Erb's point potential. Abnormalities of N11 implied a nerve root lesion whereas those of N13 with normal N11 indicated cervical cord involvement. In patients with normal N11 and N13, prolongation of P14, originating from the medial lemniscus, indicated a compressive lesion located above the level of entry to the spinal cord of the nerve stimulated. When MRI showed abnormal signals in the spinal cord, N11 or N13 or both were generally affected. SSEPs also detected functional abnormalities in the absence of morphologic changes on MRI. These findings suggest that SSEP is a sensitive technique to use as a test of functional integrity of the spinal cord.

Transcriptional activation of RACTK1 K+ channel gene by apical alkalization in renal cortical collecting duct cells

We have previously demonstrated that RACTK1 cDNA encodes a pH sensitive K+ channel expressed in the apical side of renal collecting tubule cells. To determine whether extracellular pH induces the RACTK1 gene expression in the renal cortical collecting duct (CCD) cells, we measured mRNA of the RACTK1 using cultured rabbit CCD cells. Alkalization of incubation medium activated the transcription of the RACKTK1 gene in a time- and dose-dependent manner after 1 h, and reached a maximal level after 12 h. To examine whether the stimulation of mRNA by alkalization of body fluid occurs also in vivo, mRNA levels were measured in mice loaded with acid or alkali. The RACTK1 mRNA was increased in association with the rise in urinary pH. To examine side face of the effect of pH on stimulation of mRNA, we observed the effect of pH in the apical or the basolateral side in the preparation where CCD cells were cultured on filter membrane supports. Alkalization of the apical side but not of the basolateral side, was shown to be a determinant in inducting the RACTK1 mRNA. These findings suggest that, in addition to rapid direct regulation of RACTK1 K+ channel conductance by intracellular pH, this channel is also regulated by the changes in luminal pH through synthesis of channel protein by transcriptional activation.

Electrophysiological characterization of RACTK1 K+ channel in stable cell line

RACTK1 is a pH-sensitive K+ channel cloned from rabbit renal collecting tubule cells. To characterize the function of this K+ channel in more detail, RACTK1 was transfected to an established cell line and the patch-clamp study was performed. cDNA of RACTK1 was inserted in the pMAM vector and transfected to Chinese hamster ovary cells. In one of 36 cell lines, the channel protein as expressed by the dexamethasone-induced mRNA and was detected by the specific antibody. The RACTK1 K+ channel with 80 pS was consistently observed. In inside-out patch, Ca2+ at concentrations higher than 500 nM activated the channel. Open probability was decreased by protein kinase A (from 45 to 4.2%, n+6) but not by protein kinase C. Whole cell currents of the transformed cells represented K+ conductance that was not blocked by an addition of charybdotoxin but by apamin. RACTK1 K+ channel has similar, though not identical, characteristics to the Ca2+ -activated K+ channel. RACTK1 might therefore encode a subunit of the intermediate conductance Ca2+ -activated K+ channel observed in the apical membrane of the rabbit renal collecting duct.

[Mononeuritis multiplex associated with measles virus infection]

We describe a 19-year-old patient who developed mononeuritis multiplex associated with measles virus infection. On April 30th, 1995, he suffered from fever and skin eruption, which disappeared ten days later. Thirteen days later, he noticed weakness of the fingers of both hands and forearms, and pain on both elbow joints. He was admitted to our hospital on June 12th, 1995. Neurologic examination revealed weakness and sensory disturbance, confined to the distal aspects of the right radial nerve and left median nerve. The electrodiagnostic findings confirmed those of axonal neuropathy in the right radial and left median nerves. Routine laboratory studies were normal. The cerebrospinal fluid test and EEG were normal. The IgG and IgM antibody titers against measles virus continued to be elevated in serum over four months after the onset, while they were not elevated in the cerebrospinal fluid. The corticosteroid therapy was mildly effective. Although the pathogenesis of this case is unclear, we speculate that the mononeuritis multiplex was caused by vasculitis related to the persistent measles virus infection in both elbow areas.

Cyclosporine-related encephalopathy following allogeneic bone marrow transplantation

A 46-year-old man with chronic myelogenous leukemia received allogeneic bone marrow transplantation (BMT) from a partially human leukocyte antigen (HLA)-mismatched sibling. Cyclosporine (CYA)-related encephalopathy developed on days 10 and 21 following BMT, and CYA-related thrombotic thrombocytopenic purpura (TTP) developed on day 45 following BMT. We measured serum concentrations of thrombomodulin (TM) as a marker of endothelial injury. The concentrations of TM were increased during the encephalopathy or TTP and decreased following recovery. Since CYA can cause endothelial injury, we suggest that CYA-induced endothelial injury is common to the pathogenesis of both the encephalopathy and the TTP. CYA therapy should be reinstituted with extreme caution in patients with a past history of CYA-related encephalopathy, since readministration of a low-dose CYA can evoke the immediate return of the encephalopathy.

Studies on fatigue of night duty workers at a newspaper office

Fatigue of night duty workers in different divisions of a newspaper office was investigated by physiological methods such as the Blinker, Flicker and grip methods. The relationship between fatigue and hematological parameters such as hemoglobin (Hb), the hematocrit (Ht), serum-free amino acid levels, and indices of liver function such as the GOT and GPT levels were also examined. The composing and press room workers mainly complained of the subjective symptom of muscle fatigue, while workers in the photo-engraving and editorial departments mainly complained of mental fatigue. The overall rate of fatigue in the newspaper office was about 38.1%, but varied from one division to another, being especially high in the photo-engraving and editorial departments. The subjects with fatigue had low levels of serum GOT and GPT and high levels of serum-gluconeogenic amino acids, such as aspartic acid, glutamic acid, prolin, glycine, and alanine. These altered levels of serum-free amino acids and GOT and GPT seemed to be due to increased secretion of adrenal corticoid hormone caused by the stress of fatigue.

Reassessment of second look operation for epithelial ovarian cancer

We retrospectively reviewed 91 patients with epithelial ovarian cancer who underwent second-look operation (SLO). SLO identified a persistent tumor in 18 (19.8%) of 91 patients. Of these 18 patients, 13 (72.2%) showed disease progression after SLO. Patients with a positive SLO in which the identification of the persistent disease was only possible by washing cytological study showed better prognosis than patients with macroscopic lesions. Of the 73 patients with a negative SLO, 12 (16.4%) developed recurrence after cessation of treatment. These 12 patients were from stage 1c to 3 with Grade 2 and 3 tumors. The SLO findings were more sensitive than the serum tumor marker in identifying persistent disease. Also we reviewed 55 patients having no SLO. Among 57 cases in stage 1 and 2 with Grade 1 tumor, there were no cases of recurrence, regardless of whether they had SLO or not. Our results suggest that SLO findings correlate well with the patient's prognosis. SLO may not be needed for patients in stage 1 and 2 with Grade 1 tumor. Patients with advanced stage disease with Grade 2 and 3 tumors have high-risk for recurrence after negative SLO. While SLO is still of benefit in management of ovarian cancer, refinements are needed to determine its indication and scheduling.

Specific deficit of the ON response in visual transmission by targeted disruption of the mGluR6 gene

Taking advantage of the restricted expression of metabotropic glutamate receptor subtype 6 (mGluR6) in retinal ON bipolar cells, we generated knockout mice lacking mGluR6 expression. The homozygous mutant mice showed a loss of ON responses but unchanged OFF responses to light. The mutant mice displayed no obvious changes in retinal cell organization nor in the projection of optic fibers to the brain. Furthermore, the mGluR6-deficient mice showed visual behavioral responses to light stimulation as examined by shuttle box avoidance behavior experiments using light exposure as a conditioned stimulus. The results demonstrate that mGluR6 is essential in synaptic transmission to the ON bipolar cell and that the OFF response provides an important means for transmitting visual information.

Epidemiological studies on regional differences in suicide mortality and its correlation with socioeconomic factors

To investigate regional differences in suicide mortality and its correlation with socioeconomic factors during the 1975-1990 period, we analyzed annual change in suicide mortality and 18 socioeconomic indicators among each prefectures in Japan. Annual course of age-adjusted mortality from suicide during the 1975-1985 period differed between males (increasing) and females (decreasing), because of rapidly increase in suicide mortality for middle-aged males. During the 1986-1990 period, suicide mortality decreased in both males and females. A census characteristic that suicide mortality was higher in rural districts than in urban districts intensified annually until 1985 and weakened thereafter. The factor analysis of socioeconomic indicators revealed that 1st factor was recognized as the industrial and economic activity. A high inverse correlation was observed between age-adjusted mortality from suicide and the 1st factor for males and females. In males this tendency continued until the end of the 1980s. On the whole, correlation coefficients between age-adjusted mortality from suicide and the socioeconomic indicators in males were much higher than that in females. The indicators whose annual change differed remarkably between the prefectures with an increase and a decrease in suicide mortality for males were amount of savings and frequency of bankruptcy. Therefore they were considered to be closely related to suicide mortality.

Characterization of region Ic in site I on human serum albumin. Microenvironmental analysis using fluorescence spectroscopy

Characteristics of region Ic among at least three overlapping binding regions (regions Ia, Ib and Ic) in site I on human serum albumin (HSA) were analysed using n-alkyl p-aminobenzoates (n-alkyl p-ABEs), all of which are specific fluorescent probes for region Ic. In the interaction processes between n-alkyl p-ABEs and HSA, hydrophobic interaction, van der Waals interaction and local structural changes in region Ic were found to be involved based on the results obtained by analyses of the fluorescence spectra, structure-activity relationships and thermodynamic parameters. In addition, comparison of the fluorescence spectra of n-alkyl p-ABEs in HSA and detergents indicated that the possibility of a hydrophobic region Ic around which an amino acid with cationic charge locates could not be denied because of the similarity of fluorescence spectra between n-alkyl p-ABEs in HSA and in neutral and cationic detergents. The deviation of n-alkyl p-ABEs with long alkyl chains (C9-C12) in the relationships between association constants and physicochemical properties of a series of n-alkyl p-ABEs (C1-C12) suggested that region Ic possess an optimal depth. A conformational change of HSA with increasing pH (pH 6-9) generated an increase in hydrophobicity and adaptability of the binding region and made interaction easy, with an increase in adaptability of the binding region Ic; consequently, it enhanced the binding of n-alkyl p-ABEs to HSA.

Epidemiological study on relationship between breast cancer mortality and dietary factors

To elucidate the effects of nutritional factors on regional differences in breast cancer mortality in Japan, the statistical analysis was made using the results of the national nutrition surveys in 12 districts from 1966 to 1980 and age-adjusted mortality from breast cancer from 1966 to 1990. The correlation analysis between food or nutrient intake and breast cancer mortality was performed with a fixed time lag of 10 years. Dietary factors such as wheat, milk, meats, animal fat, animal protein, total fat, saturated fatty acid (SF) and monounsaturated fatty acid (MUF) were correlated highly positively with breast cancer mortality. The correlation analysis between increase rates in age-adjusted mortality from breast cancer and increase rates in food or nutrient intake was also examined. Highly positive correlations were obtained between breast cancer mortality and following dietary factors; oils and fats, fruits, milk, total fat, vegetable fat, SF, MUF and n-6 polyunsaturated fatty acid. Factor analysis using fat intake by 12 districts revealed the factor representing the intake of fat component resulting from ingestion of animal fat. This factor showed a positive correlation with age-adjusted mortality from breast cancer. The findings suggested that the dietary factors due to intake of Westernized meals, especially SF had the effect on breast cancer mortality in Japan.

Relationship between physical exercise and health of the elderly people in a rural community

The significance of life style and regular physical exercise for health of elderly people in a rural community was evaluated by questionnaires. The subjects studied were a group who had been playing gate ball (such as croquet) for more than three years (N = 86) and a group who had not (N = 255). Significantly more males in the group playing gate ball (GB group) than in the group not playing gate ball (n-GB group) reported feeling healthier than three years before. The average overall score for life style which indicates a healthier life style was analyzed. The score for life style of males was significantly lower in the GB group than in the n-GB group. Significantly more males in the GB group did not take snacks or smoke than those in the n-GB group. Regarding regular physical exercise, significantly fewer females in the GB group went for a daily walk than those in the n-GB group. The average score for integrated regular physical exercise was significantly higher in the GB group than in the n-GB group. The scores for regular physical exercise of females in the GB group, even in spite of disability or hypertension, were significantly higher than those in the n-GB group. From this survey it appears that regular physical exercise including gate ball may be beneficial for health of elderly people in a rural community.

Tumor blood flow measured using dynamic computed tomography

RATIONALE AND OBJECTIVES

A method for measuring the tumor blood flow (TBF) by means of dynamic computed tomography (DCT) was devised and investigated.

METHODS

Twenty-seven patients with superficial tumors underwent measurement of TBF by the new DCT method. For all of the 27 patients, the thermal clearance method was employed to measure the relative tumor blood flow (RTBF). For 16 patients, TBF was measured by oxygen-15-gas positron-emission tomography (PET). The TBF values measured by DCT were compared with the RTBF by the thermal clearance method and the TBF by PET.

RESULTS

The results demonstrated a linear relationship.

CONCLUSIONS

The newly devised DCT method yields reliable data in measuring TBF.

Neonatal group B streptococcal sepsis during 2 years of a universal screening program

OBJECTIVE

To assess the feasibility and efficacy of a protocol for universal screening for group B streptococci combined with selective intrapartum prophylaxis at a teaching hospital.

METHODS

This is a descriptive study of experience with a standardized protocol in which patients were screened at 26-28 weeks with a rectal and genital culture placed directly in selective media. As risk factors, we used clinical chorioamnionitis, preterm birth, and rupture of the membranes greater than 12 hours. Participants were all women receiving prenatal care at our hospital. Major outcomes were compliance and neonatal sepsis due to group B streptococci.

RESULTS

The prevalence of rectal and genital group B streptococci was 18.5% of 3721 screened women. Of culture-positive women, 35% developed risk factors (9% chorioamnionitis, 13% preterm birth, and 13% membrane rupture greater than 12 hours at term). With strict application of criteria, the compliance rate in administering indicated prophylaxis was 80.3%. Of women receiving prophylaxis, 42% had the first dose for 4 hours or less before delivery. There were five cases of group B streptococcal neonatal sepsis, resulting from either protocol violations, protocol failures, or both. Compared to the historic rate of group B streptococcal sepsis of 1.5 per 1000 births at our hospital, the rate in these 2 years was 1.0 per 1000 (1.6 per 1000 in the first year and 0.5 per 1000 in the second).

CONCLUSIONS

It is feasible to conduct such a protocol, but compliance is only moderately good because the algorithm is complex. The protocol is not foolproof in preventing neonatal group B streptococcal sepsis, as there are protocol failures and violations.

[A case of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) with bilateral recurrent nerve palsy and primary alveolar hypoventilation--comparative studies of the histological findings of the two sural nerve biopsies with 9 years interval]

A 27-year-old man noticed a tingling sensation in his fingers and toes in early 1982, at the age of 18 years, and his symptom gradually progressed in the following several months. In December 1982, based on neurological and laboratory examinations including the first sural nerve biopsy on the right side, a diagnosis of axonal sensory neuropathy of unknown etiology was made. During the following years, muscle weakness in the distal limbs and hoarseness developed and progressed, and the sensory impairments became gradually evident. On the second neurological examination in July 1991, he showed soft palate palsy and bilateral recurrent nerve palsy. The intrinsic muscles of hands and feet were atrophic, and pes cavus was noted bilaterally. There was mild to moderate weakness in the distal muscles of both limbs. Ankle jerk was absent and other tendon reflexes were decreased in both limbs. A mild to moderate decrease of both superficial and deep sensations with mild paresthesia was noted in both hands and feet. Routine laboratory findings were unremarkable. In blood gas analysis, hypercapnea and respiratory acidosis were found. Spirometry showed an increase of residual volume, and alveolar CO2-pulmonary ventilation response test suggested the presence of primary alveolar hypoventilation caused by hypofunction of the medullary respiratory center. In nerve conduction studies, motor nerve conduction velocities were moderately reduced in bilateral median and ulnar nerves. Distal latencies of M-waves were prolonged in bilateral median nerves. Temporal dispersion of M-wave was found in the left tibial nerve. The amplitudes of sensory action potentials were moderately reduced in bilateral median and sural nerves.(ABSTRACT TRUNCATED AT 250 WORDS)