Trifluoroethanol-induced stabilization of the alpha-helical structure of beta-lactoglobulin: implication for non-hierarchical protein folding

Trifluoroethanol (TFE) is known to stabilize the alpha-helical structure in proteins and their fragments. However, the relationship between the TFE-induced structures and the native structure is not clear. Here we show that beta-lactoglobulin, which consists predominantly of beta-sheets, exhibited a markedly high propensity to form an alpha-helical structure in the presence of TFE, as measured by far-UV circular dichroism. A cooperative transformation from the beta-sheet structure to an alpha-helical structure occurred at a TFE concentration between 10% and 20%. These results were in contrast to a gradual beta-sheet to alpha-helix transition of the constant fragment of the immunoglobulin light chain, which is also a beta-sheet protein. To understand the significance of the high helical propensity of beta-lactoglobulin, we measured the TFE-induced conformational transition of more than 20 proteins of various secondary structural types. Whereas the alpha-helical proteins showed a propensity to form an extensive helical structure in TFE, the helical propensity of proteins with a low helical content in the native state varied. The helical content in TFE was correlated more with the helical content predicted by a secondary structure prediction than with the helical content of the native structure, suggesting that the stability of the helical structure in TFE is determined by local interactions between nearby amino acid residues. Our results suggest that an alpha-helical intermediate can accumulate during the refolding process of beta-lactoglobulin and that a hierarchical model of protein folding is not necessarily true for some beta-sheet proteins including beta-lactoglobulin.

Effects of delapril on stroke, kidney dysfunction and cardiac hypertrophy in stroke-prone spontaneously hypertensive rats

This study was performed to investigate the beneficial effects of prolonged treatment with an angiotensin converting enzyme (ACE) inhibitor, delapril, on the appearance of symptoms of hypertensive cardiovascular disease in stroke-prone spontaneously hypertensive rats (SHRSP). Cardiovascular disease symptoms: stroke, kidney dysfunction and cardiac hypertrophy, were evaluated by monitoring the incidence of stroke signs, urinary excretion of protein and the heart weight, respectively. The SHRSP that were kept under salt-loaded conditions (1% NaCl drinking solution) from six weeks of age developed severe hypertension, showed an increased incidence of stroke signs and increased urinary excretion of protein. Long-term treatment with delapril (10mg/kg/day, p.o. for four weeks) decreased the blood pressure and completely inhibited the incidence of stroke signs and the increase in urinary excretion of protein. In SHRSP that were kept under normal conditions (without 1% NaCl drinking solution), long term treatment with delapril at the same dose decreased the heart weight and, after five weeks of treatment, left ventricular weight was decreased significantly and the wall/lumen ratio of small coronary arterioles and the thickness of the left ventricular wall were decreased slightly. These results indicate that delapril can prevent the development of symptoms of hypertensive cardiovascular diseases: stroke, kidney dysfunction and cardiac hypertrophy, with antihypertensive activity in SHRSP.

Chloride transport mechanism in swine tracheal submucosal gland cells

To clarify the mechanism for Cl- transport in swine tracheal submucosal gland cells, we measured chloride (Cl-) flux by means of a Cl(-)-sensitive fluorophore, 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ). An abrupt change of Cl(-)-free bath to a Cl(-)-containing (114 mM) solution induced the Cl- influx into the cells at a rate of 0.52 mM/s (p < 0.05). Removal of sodium (Na+) and the addition of 0.5 mM furosemide significantly reduced the rate of gradient-induced Cl- influx to 0.21 (p < 0.05) and 0.19 mM/s (p < 0.05), respectively. In gland tissue treated with 0.1 mM ouabain, the removal of external potassium (K+) in the presence of 5 mM barium significantly reduced the rate of Cl- influx to 0.21 mM/s (p < 0.05). An abrupt change from a Cl(-)-containing bath to a Cl(-)-free solution induced the Cl- efflux from the cells at a rate of 0.10 mM/s (p < 0.05). Acetylcholine increased the rate of gradient-induced Cl- efflux in a dose-dependent manner to 0.78 mM/s at 10(-6) M. This effect of acetylcholine was significantly diminished by diphenylamine-2-carboxylic acid (DPC, 10(-9) M), a Cl- channel blocker (p < 0.05). Isoproterenol (10(-5) M) had no effect on the Cl- efflux. These findings indicate that a Na-K-Cl co-transporter plays a major role in Cl- entry, and that Cl- efflux was activated by cholinergic receptor stimulation, but not by beta-adrenergic stimulation, via a DPC-inhibitable Cl- channel.

Effects of hyperthermia and cepharanthin on adriamycin accumulation with changes in extracellular pH

We compared adriamycin (ADR) accumulation with the intensity of intracellular fluorescence of 3,3'-(di-n-hexyl)-2,2'-oxacarbocyanine iodide (NK-2280), an indicator of cell membrane potential, after hyperthermia and examined the effects of cepharanthin (CEP) on the accumulation of ADR and NK-2280 in wild and ADR-resistant strains of Ehrlich ascites tumour (EAT) cells. Among wild 0.2 and 1-microgram ADR-resistant strains of EAT cells, intracellular accumulation of both ADR and NK-2280 decreased with an increase of ADR resistance. Hyperthermia at 42 degrees C and CEP induced a marked increase in accumulation of both ADR and NK-2280 in the ADR-resistant strains of EAT cells. The increase in ADR accumulation by hyperthermia and CEP is possibly due to an increase in the cell membrane potential and the inhibition of ADR efflux by CEP respectively. In the wild strain of EAT cells, we also evaluated the effect of extracellular pH change on ADR accumulation and the cell membrane potential and their alteration by hyperthermia and CEP. ADR accumulation decreased as pH decreased, but the cell membrane potential was not appreciably affected by pH change so far examined. Hyperthermia alone or combined with CEP significantly increased ADR accumulation in a pH range from 6.2 to 7.6. Hyperthermia increased the accumulation of ADR in the tumour cells, although its pH dependency was not completely resolved. CEP enhanced ADR accumulation more markedly in ADR-resistant cells than in wild-type cells. Therefore, the combination of hyperthermia and CEP may be very effective to increase the ADR cytotoxicity to ADR-resistant tumours.

Role of angiotensin II in cerebrovascular and renal damage in deoxycorticosterone acetate-salt hypertensive rats

OBJECTIVE AND DESIGN

To study the effects of blockade of the renin-angiotensin system on the development of hypertension and end-organ damage in hyporeninaemic deoxycorticosterone acetate (DOCA)-salt hypertensive rats, using an angiotensin II (Ang II) receptor antagonist (TCV-116) or an angiotensin converting enzyme (ACE) inhibitor (enalapril).

METHODS

DOCA-salt hypertensive rats were produced by uninephrectomy, implantation with DOCA pellets and 1% NaCl loading. TCV-116 (0.1 or 1 mg/kg) or enalapril (10 mg/kg) was given orally once a day from 3 to 6 weeks after the operation. Body weight, blood pressure, plasma renin and creatinine, urinary protein and blood urea nitrogen were measured. After 3 weeks' treatment, oedema and omega 3-subtype benzodiazepine receptor binding in the brain were measured.

RESULTS

Three weeks after the operation the blood pressure in the DOCA-salt hypertensive rats was approximately 200 mmHg, and the plasma renin concentration was lower than in sham-operated rats. However, after a further 3 weeks the renin concentration was slightly above the normal level, and this increase was accompanied by a decrease in body weight and increases in blood urea nitrogen, plasma creatinine, urinary protein and omega 3-subtype benzodiazepine receptor binding in the cerebral cortex, and by brain oedema. Treatment with TCV-116 or enalapril prevented renal damage and decrease in body weight with little effect on blood pressure. Enalapril prevented brain oedema and the increase in benzodiazepine binding in the brain cortex, and 1 mg/kg TCV-116 prevented them markedly.

CONCLUSIONS

Although the hypertension in DOCA-salt hypertensive rats is independent of the renin-angiotensin system, the degree of cerebral and renal damage is associated with the activity of the renin-angiotensin system and has little relationship with the blood pressure level.

The ability of bovine mitochondrial transfer RNAMet to decode AUG and AUA codons

The ability of bovine mitochondrial tRNA(Met) with the anticodon f5CAU (where f5C is 5-formylcytidine) to decode AUG and AUA codons was examined in a codon-dependent ribosomal binding assay. The AUG codon stimulated the binding of Met-tRNA(Met) to mitochondrial ribosomes in the presence of EF-Tu/TSmt. In contrast, the AUA codon did not promote the binding to mitochondrial Met-tRNA to the ribosome. To investigate the translation of the AUG and AUA codons more fully, an in vitro translation system from bovine liver mitochondria was developed. The activity of this system was greatly enhanced by the addition of 1 mM spermine and reached about half the activity observed with a comparable translational system from E coli. Two types of mRNA containing either AUG or AUA codons were synthesized using T7 RNA polymerase to transcribe their chemically synthesized genes. In the E coli system, the AUG-containing mRNA was translated as Met and the AUA-containing mRNA was translated as Ile. The AUG-containing mRNA but not the AUA-containing mRNA was translated as Met by the mitochondrial translational system. The process by which the AUA codon is translated as Met in the mitochondrial system remains to be clarified.

Influence of the extracellular pH, an inhibitor of Na+/H+ exchanger and an inhibitor of Cl-/HCO3-exchanger on adriamycin accumulation

We examined the influence of the extracellular pH, an inhibitor of Na+/H+ exchanger: 3,5-diamino-6-chloro-N-(diaminomethylene) pyrazinecarboxamide (amiloride), and an inhibitor of Cl-/HCO3-: 4,4 -diisothiocyanatostilbene -2,2 -disulfonic acid (DIDS) on the accumulation of adriamycin (ADR) in Ehrlich ascites tumor cells and their adriamycin-resistant strain. A good correlation between the increases in ADR accumulation and the extracellular pH was shown in the both strains. The ADR accumulation decreased with an increasing concentration of amiloride or DIDS in both strains. These findings demonstrate that the influx of ADR was related closely to the efflux of H+ or to the activities of Na+/H+ ex-changer and Cl-/HCO3-exchanger. Therefore, raising the extracellular pH and enhancement of the activities of either Na+/H+ exchanger or Cl-/HCO3-exchanger may result in the potentiation of the cytotoxic effect of ADR through increase of ADR influx.

Smoldering gamma delta T-cell granular lymphocytic leukemia associated with pure red cell aplasia

We present a case of granular lymphocytic leukemia (GLL) associated with pure red cell aplasia (PRCA). Twenty-seven percent of the peripheral blood mononuclear cells (PBMC) were positive for TCR delta 1, but not for delta TCS1 (V delta 2), and a rearrangement of the TCR chain (J delta 1) gene was detected. The PBMC and serum from the patient slightly suppressed CFU-E but not BFU-E colony formation in vitro. These findings suggest that monoclonal proliferation of TCR gamma delta-positive granular lymphocytes (GL) can be associated with PRCA even in a patient having a small proportion of leukemia GL, which we propose to designate as 'smoldering GLL'.

Direct antitumor effect of cepharanthin and combined effect with adriamycin against Ehrlich ascites tumor in mice

Direct antitumor effect of cepharanthin (CEP) and the combined effect with adriamycin (ADR), as well as the effect of CEP against body weight loss caused by treatment of ADR were evaluated using ICR mice bearing Ehrlich ascites tumor. Single administration of CEP reduced tumor growth compared to that of the untreated control, but not significantly. However, multiple administration of CEP reduced the tumor growth significantly compared to that of the untreated control (p < 0.001). Simultaneous administration of intratumoral CEP and intravenous ADR reduced the tumor growth significantly compared to that of ADR alone (p < 0.05). Further, CEP restored body weight loss caused by the treatment of ADR (p < 0.01). These findings indicate that the combined administration of CEP and ADR may be effective in cancer treatment.

Higher-order structure of bovine mitochondrial tRNA(SerUGA): chemical modification and computer modeling

On the basis of enzymatic probing and phylogenetic comparison, we have previously proposed that mammalian mitochondrial tRNA(sSer) (anticodon UGA) possess a slightly altered cloverleaf structure in which only one nucleotide exists between the acceptor stem and D stem (usually two nucleotides) and the anticodon stem consists of six base pairs (usually five base pairs) [Yokogawa et al. (1991) Nucleic Acids Res. 19, 6101-6105]. To ascertain whether such tRNA(sSer) can be folded into a normal L-shaped tertiary structure, the higher-order structure of bovine mitochondrial tRNA(SerUGA) was examined by chemical probing using dimethylsulfate and diethylpyrocarbonate, and on the basis of the results a tertiary structure model was obtained by computer modeling. It was found that a one-base-pair elongation in the anticodon stem was compensated for by multiple-base deletions in the D and extra loop regions of the tRNA(SerUGA), which resulted in preservation of an L-shaped tertiary structure similar to that of conventional tRNAs. By summarizing the findings, the general structural requirements of mitochondrial tRNAs necessary for their functioning in the mitochondrial translation system are considered.

[An approach to home therapy for cancer pain patients]

Recently, in consideration of cost performance and improvement in quality of life (QOL) of the patient, the significance of home care and outpatient treatment has also been recognized in Japan. A terminal cancer patient who had local recurrence in the pelvic region after surgery for rectum carcinoma, was treated for cancer pain by us with a continuous epidural infusion of morphine by means of a prolonged operating continuous infusion device. The treatment made home therapy possible and allowed the patient to return to normal social activities. Based on this case, the significance of and issues regarding home therapy are discussed in this study.

Color Doppler sonography of hepatic tumors with a galactose-based contrast agent: correlation with angiographic findings

OBJECTIVE

The purpose of this study was to evaluate the clinical usefulness of a galactose-based, IV sonographic contrast agent for assessing tumor vascularity and diagnosing hepatocellular carcinoma.

SUBJECTS AND METHODS

We used color Doppler sonography with the sonographic contrast agent to examine 22 patients with 26 hepatic nodules (18 hepatocellular carcinomas, four hemangiomas, two adenomatous hyperplasias, and two metastatic tumors). In all 26 lesions, intratumoral arterial flow signals were examined before and after IV injection of the sonographic contrast agent at three concentrations (200, 300, and 400 mg/ml), and the findings on color Doppler sonograms of each lesion were correlated with angiographic findings.

RESULTS

Conventional color Doppler sonograms showed flow in nine hepatocellular carcinomas (50%) and one hemangioma (25%). When the contrast agent was used, color Doppler sonograms showed intratumoral arterial flow in 11 hepatocellular carcinomas (61%) and one hemangioma (25%) at a concentration of 200 mg/ml, in 14 hepatocellular carcinomas (78%) and 1 hemangioma (25%) at 300 mg/ml, and in 15 hepatocellular carcinomas (83%) and two hemangiomas (50%) at 400 mg/ml. The detectability of intratumoral arterial flow was improved by the contrast agent, especially in hepatocellular carcinomas smaller than 30 mm in diameter. Angiography revealed neovascularization or staining in 15 hepatocellular carcinomas, four hemangiomas, and none of the adenomatous hyperplasias or metastatic tumors. Among 15 angiographically hypervascular hepatocellular carcinomas, the detection rate of intratumoral arterial flow with contrast-enhanced color Doppler sonography was 73% at 200 mg/ml, 93% at 300 mg/ml, and 100% at 400 mg/ml. No intratumoral Doppler signals were depicted with the use of contrast agent in any angiographically undetected tumors.

CONCLUSION

Preliminary findings on contrast-enhanced color Doppler sonograms correlate well with angiographic findings for evaluating tumor vascularity. This noninvasive technique may be useful in diagnosing hypervascular hepatocellular carcinomas.

Protein structural similarities predicted by a sequence-structure compatibility method

A method for protein structure prediction has been developed, which evaluates the compatibility of an amino acid sequence with known 3-dimensional structures and identifies the most likely structure. The method was applied to a large number of sequences in a database, and the structures of the following proteins were predicted: (1) shikimate kinase (SKase), (2) the hydrophilic subunit of mannose permease (IIABMan), (3) rat tyrosine aminotransferase (Tyr AT), and (4) threonine dehydratase (TDH). The functional and evolutionary implications of the predictions are discussed. (1) The structural similarity between SKase and adenylate kinase was predicted. Alignment of their sequences reveals that the ATP-binding type A sequence motif and 2 ATP-binding arginine residues are conserved. The prediction suggests a similarity in their functional mechanisms as well as an evolutionary relationship. (2) The structural similarity between IIABMan and galactose/glucose-binding protein (GGBP) was predicted. The IIA and IIB domains are aligned with the N- and C-terminal domains of GGBP, respectively. The 2 phosphorylated residues, His 10 and His 175, of IIABMan are threaded onto loops located in the substrate-binding cleft of GGBP. The prediction accounts for the phosphoryl transfer from His 10 to His 175, and to the sugar substrate. (3) The structural similarity between rat Tyr AT and Escherichia coli aspartate AT was predicted, as well as (4) the structural similarity between TDH and the tryptophan synthase beta subunit. Predictions (3) and (4) support the previous predictions based on observations of the functional similarities between the proteins.

[Reproductive and developmental toxicity studies of lactitol (NS-4) (2)--Teratogenicity study in rats by oral administration]

A teratogenicity study of lactitol, a hepatic encephalopathy drug, was conducted in Sprague-Dawley rats. Female rats were given lactitol orally at dose levels of 0 (control), 0.7, 2.65 and 10 g/kg from day 7 to day 17 of pregnancy. Twenty-two female rats per dose level were sacrificed on day 20 of pregnancy for examination of their fetuses, and thirteen pregnant rats per dose level were allowed to deliver naturally for postnatal examination of their offspring. The high dose of lactitol caused diarrhea or soft stool in pregnant rats. The food consumption of female rats decreased in the intermediate and high dose groups. The water consumption of female rats increased in the high dose group. The drug failed to alter the body weight of female rats. The weights of cecum of dams increased in the intermediate and high dose group. The high dose caused enlargement of cecum in dams. The drug failed to alter the numbers of corpora lutea and implantations, fetal mortality, the number of live fetuses, body weight of live fetus, sex ratio, and external, visceral and skeletal development of fetuses. Lactitol did not affect the delivery of dams, the number of live newborns, birth index, external development, body weight, viability index, weaning index, and sex ratio of weanlings. Nor did lactitol have any adverse effect on the postnatal development of the first (F1) generation offspring, such as differentiation, emotionality, motor ability, learning ability or reproductive performance. Nor did lactitol have any adverse effect on the second (F2) generation offspring. The results show that no-effect dose levels of lactitol are 0.7 g/kg for general toxicity in mother animals, 10 g/kg for reproductive function in mother animals and their offspring.

[Reproductive and developmental toxicity studies of lactitol (NS-4) (4)--Perinatal and postnatal study in rats by oral administration]

A perinatal and postnatal study of lactitol, a hepatic encephalopathy drug was conducted in Sprague-Dawley rats. Female rats were given lactitol orally at dose levels of 0 (control), 0.7, 2.65 and 10 g/kg from day 17 of pregnancy to day 21 after delivery. All pregnant rats per level were allowed to deliver naturally for postnatal examination of their offspring. The high dose caused diarrhea or soft stool in dams. The high dose suppressed the body weight of dams during the perinatal period. The food consumption of dams decreased in the intermediate and high dose groups. The water consumption of dams increased in the high dose group. The high dose caused enlargement of cecum and increase of weights of cecum in dams. The drug failed to affect the delivery of dams and gestation index. However, high dose caused prolongation of gestation period. Two dams in the high dose group failed to nurse their all newborns during early lactation. The drug did not affect the number of live newborns, birth index, external appearance, body weight, viability index, weaning index, and sex ratio of weanlings. Nor did lactitol have any adverse effect on the postnatal development of the first (F1) generation offspring, such as differentiation, emotionality, motor ability, learning ability or reproductive performance. Nor did lactitol have any adverse effect on the second (F2) generation offspring. The results show that the no-effect dose levels of lactitol are 0.7 g/kg for general toxicity in mother animals, 2.65 g/kg for reproductive function in mother animals, and 10 g/kg for their offspring.

[Reproductive and developmental toxicity studies of lactitol (NS-4) (1)--Fertility study in rats by oral administration]

A study of fertility and fetal development was conducted in Sprague-Dawley rats. Male rats were given lactitol, a hepatic encephalopathy drug, orally from 63 days before mating to the end of mating period. Female rats were given from 14 days before mating to day 7 of pregnancy. The dose levels for both males and females were 0 (control), 0.7, 2.65 and 10 g/kg. The females were sacrificed on day 20 of pregnancy for examination of their fetuses. The decrease in food consumption in either male or female was observed in the intermediate and high dose groups. The high dose caused soft stool, diarrhea and increase in water consumption in either male or female. Moreover, the high dose caused salivation and suppression of body weight gain in male. In the pathological examination, the enlargement of cecum were observed in male of the intermediate and high dose groups. The increase in cecum weight were observed in male in all lactitol groups, and in female of the high dose group. Lactitol did not affect on copulation and fertility indexes in either male or female rats. Lactitol failed to affect on estrous cycle in female rats, and number of corpora lutea, implantations and preimplantation egg losses. In the fetal examination, lactitol did not affect on the development of live fetuses. The results show that no-effect dose levels of lactitol are less than 0.7 g/kg in male rats and 0.7 g/kg in female rats for general toxicity, and 10 g/kg for reproductive function in parent animals and fetuses.

Characterization of basic fibroblast growth factor-mediated acceleration of axonal branching in cultured rat hippocampal neurons

We analyzed in more detail the effect of basic fibroblast growth factor (bFGF) on morphogenesis of rat hippocampal neurons in dissociated cell culture. As a result, we found that bFGF selectively promoted the bifurcation and growth of axonal branches without affecting the elongation rate of primary axons. The dendritic outgrowth was rather inhibited by bFGF. These effects of bFGF resulted in increased complexity of axonal trees. The effect of bFGF was concentration dependent (0.1-10 ng/ml) and was abolished by the presence of anti-bFGF neutralizing antibody. The accelerated axonal branch formation in the presence of bFGF was restored to the basal rate following removal of bFGF, suggesting that the action of bFGF is reversible and that the continuous presence is required for bFGF to accelerate the branch formation. bFGF probably works as a progression signal rather than as a triggering signal. The bFGF-mediated acceleration of axonal branch formation was blocked by treatment with heparitinase and by tyrosine inhibitors, herbimycin A and lavendustin A, indicating the importance of heparan sulfate and tyrosine kinase in bFGF signal transduction. Treatment with a protein kinase C activator phorbol-12-myristate-13-acetate did not significantly affect the neurite branching, and the action of bFGF was not blocked by a protein kinase C inhibitor staurosporine. Protein kinase C is unlikely to play a role in branch formation. The novel action of bFGF as a regulator of axonal branching must be a particularly useful model for the study of neuritogenesis and synaptogenesis of brain neurons.

Michael addition-type 4-hydroxy-2-nonenal adducts in modified low-density lipoproteins: markers for atherosclerosis

It has been proposed that plasma low-density lipoprotein (LDL) undergoes oxidative modification before it can give rise to foam cells in atherosclerosis. Oxidation of LDL generates a variety of reactive aldehyde products including 4-hydroxy-2-nonenal (HNE), which may covalently attach to the LDL apolipoproteins. We here present direct evidence that HNE derivatization of LDL forms Michael addition-type adducts of HNE with histidine and lysine residues of apolipoprotein B-100 (apoB) and also demonstrate the utility of an antibody specific to the HNE adducts generated in the LDL treated with HNE or oxidatively modified by Cu2+ or cultured endothelial cells. HNE adducts present in the LDL that had been treated with HNE were attested to be Michael addition-type adducts on the basis of the fact that incubation of LDL with 1 mM HNE (2 h, 37 degrees C) resulted primarily in the formation of Michael addition-type HNE-histidine (39.9 mol/mol of LDL) and HNE-lysine (19.3 mol/mol of LDL) adducts. An enzyme-linked immunosorbent assay (ELISA) and an SDS-polyacrylamide gel electrophoresis (SDS-PAGE)/immunoblot analysis of HNE-modified LDL demonstrated that these HNE adducts were detectable with the HNE-specific antibody affinity-purified with the Michael adduct (HNE-histidine) as a ligand. The following lines of evidence indicated the presence of Michael addition-type HNE adducts in the oxidatively modified LDL in vitro: (i) Amino acid analysis of LDL that had been treated with Cu2+ (24 h, 37 degrees C) demonstrated the presence of a Michael addition-type HNE-histidine adduct (7-9 mol/mol of LDL).(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of hydronephrosis caused by renal stones with elevated serum levels of CA-19-9 and CA-125]

A case of hydronephrosis caused by renal stones with elevated serum levels of carbohydrate antigens 19-9 (CA-19-9) and 125 (CA-125) is reported. A 74-year-old woman was hospitalized with pyelonephritis. The results of computerized tomography and endoscopy suggested that the patient did not have pancreatic or ovarian cancer, but laboratory tests were significant for serum CA-19-9 greater than 1,000 U/ml (normal less than 37) and serum CA-125 78 U/ml (normal less than 35), which are markers for such tumors. Abdominal X-ray films showed stones in the pelvis of the right kidney. Excretory urography showed that the right kidney was not functioning. Computerized tomography showed severe right hydronephrosis with a thin renal cortex. Complete obstruction of the ureteropelvic junction of the kidney was seen by retrograde pyelography. During percutaneous pyelography, aspiration of the pelvic urine was done, and the sample had a high concentration of CA-19-9 (250,000 U/ml), but no cancer cells. The patients underwent right nephrectomy. The pelvic urine was tested for both CA-19-9 and CA-125 this time, and both were high (190,000 U/ml and 5,100 U/ml, respectively). Pathological evaluation showed no evidence of a malignant tumor. The epithelium lining the renal pelvis was stained for both CA-19-9 and CA-125 using the avidin-biotin-peroxidase complex method. Serum levels of the markers returned to normal after nephrectomy.

Sequential changes in stem cell markers in peripheral blood and leukapheresis samples after injections of recombinant human granulocyte colony-stimulating factor in patients with urogenital malignant solid tumors: a preliminary study

In order to evaluate the mobilization effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on peripheral blood stem cells (PBSCs), rhG-CSF was given to patients with urogenital malignancy before chemotherapy. Markers for the stem cells, such as colony forming unit-granulocyte/macrophage (CFU-GM) and burst forming unit-erythrocyte (BFU-E), were sequentially monitored in peripheral blood and leukapheresis samples. Five patients, including a 13-year-old boy, were given 5 micrograms/kg rhG-CSF subcutaneously: the pediatric case for four consecutive days and the adult cases for six consecutive days (53-72 years of age). None of the patients had received chemotherapy within the four weeks prior to the start of the rhG-CSF series. PBSC collections were performed on the fifth day in the pediatric case and on the fifth and seventh days in the adult cases. Progenitor cells were monitored by methyl-cellulose cell culture techniques. CFU-GM on day 5 of the rhG-CSF series in peripheral blood increased 14- to 53-fold compared with samples taken immediately before the series. CFU-GM in the leukapheresis products on day 5 was greatest (70 x 10(3)/kg) in the pediatric case and least (14 x 10(3)/kg) in the oldest patient's case. The totals of the CFU-GM collected by two phereses in the adult cases were 21-73 x 10(3)/kg and the totals of CD34 positive cells were 0.6 to 1.4 x 10(6)/kg. The data suggest rhG-CSF to induce sufficient PBSCs for bone marrow rescue into the peripheral blood without any preceding chemotherapy. The patient's age may, however, be a contributory factor in using this method.

A tRNA-like structure is present in 10Sa RNA, a small stable RNA from Escherichia coli

We have determined that 10Sa RNA (one of the small stable RNAs found in Escherichia coli) has an interesting structural feature: the 5' end and the 3' end of 10Sa RNA can be arranged in a structure that is equivalent to a half-molecule (acceptor stem and TFC stem-loop) of alanine tRNA of E. coli. Primer-extension analysis of 10Sa RNA extracted from a bacterial mutant with temperature-sensitive RNase P function revealed that the precursor to 10Sa RNA (pre-10Sa RNA) is folded into a pre-tRNA-like structure in vivo such that it can be cleaved by RNase P to generate the 5' end of the mature 10Sa RNA. The purified 10Sa RNA can be charged with alanine in vitro. Disruption of the gene encoding 10Sa RNA (ssrA) caused a reduction in the rate of cell growth, which was especially apparent at 45 degrees C, and a reduction in motility on semisolid agar. These phenotypic characteristics of the deletion strain (delta ssrA) allowed us to investigate the effects of some mutations in 10Sa RNA in vivo, although the exact function of 10Sa RNA still remains unclear. When the G.U pair (G3.U357) in 10Sa RNA, which may be equivalent to the determinant G.U pair of alanine tRNA, was changed to a G.A or G.C pair, the ability to complement the phenotypic mutations of the delta ssrA strain was lost. Furthermore, this inability to complement the mutant phenotypes that was caused by the substitution of the determinant bases by a G.A pair could be overcome by the introduction of a gene encoding alanyl-tRNA synthetase (alaS) on a multicopy plasmid. The evidence suggests that the proposed structural features of 10Sa RNA are indeed manifested in vivo.

Primary and higher order structures of nematode (Ascaris suum) mitochondrial tRNAs lacking either the T or D stem

By fractionation using polyacrylamide gel electrophoresis and/or a preparative hybrid selection method employing solid-phase DNA probes, we prepared and characterized mitochondrial tRNAs from the body wall muscle of Ascaris suum, all of which are thought to lack either the T stem or the D stem from their gene sequences (Okimoto, R., and Wolstenholme, D. R. (1990) EMBO J. 10, 3405-3411). Some of the partially purified tRNAs were appreciably aminoacylated with an extract of A. suum mitochondria. The three species sequenced had CCA sequence at their 3'-ends, and tRNA(Met) had 5-formylcytidine at the anticodon first position, a new modified nucleoside found at the same position of bovine mitochondrial tRNA(Met) (Moriya, J., Yokogawa, T., Wakita, K., Ueda, T., Nishikawa, K., Crain, P. F., Hashizume, T., Pomerantz, S. C., McCloskey, J. A., Kawai, G., Hayashi, N., Yokoyama, S., and Watanabe, K. (1994) Biochemistry 33, 2234-2239). Enzymatic probing of these tRNAs supported the secondary structural model proposed by Okimoto and Wolstenholme in the reference cited above. Chemical probing of tRNA(Phe) demonstrated the existence of tertiary interactions between the (T arm-variable loop)-replacement loop and the D arm. The results suggest that these tertiary interactions enable the bizarre tRNAs of nematode mitochondria to maintain an L-shape-like structure in order to function in the nematode mitochondrial translation system.