MHC class I chain-related gene alleles 5 and 5.1 are transmitted more frequently to type 1 diabetes offspring in HBDI families

Type 1 diabetes mellitus (T1DM) is an autoimmune disease characterized by autoimmune destruction of pancreatic beta cells. Genetic and environmental factors contribute in this disease. There is evidence that MHC class I chain-related gene (MIC-A) plays a role in the susceptibility to this and other autoimmune diseases. There are five alleles of the MIC-A gene, which consist of different repetitions of GCT. In particular, MIC-A alleles 5 and 5.1 (the former with five repetitions of GCT, the latter with five repetitions and one additional insertion of nucleotide G) have been found to be associated with susceptibility to and age at onset of T1DM. The aim of our study was to analyze the transmission of these MIC-A alleles to T1DM-affected offsprings in HBDI families. These are multiplex families with affected offsprings and unaffected parents. DNA samples were amplified for MIC-A using fluorescence-labeled primers and analyzed on an ABI prism DNA sequencer. The transmission of alleles was then analyzed using pedigrees of families also obtained from HBDI. We analyzed 78 families and found that MIC-A alleles 5 and 5.1 are present and transmitted more frequently than expected. Heterozygotic parents for MIC-A alleles 5 and 5.1 were excluded from the study. Our results suggest that MIC-A alleles 5 and 5.1 are associated with susceptibility to T1DM in family studies.

Mutation screening of the FSH receptor gene in infertile men

Follicle stimulating hormone (FSH) is important for controlling spermatogenesis through binding with its receptor. However, little information is available on mutations of the FSH and its receptor gene in infertile men. To study the genetic defects, which caused problems in spermatogenesis, we screened the point mutations of the FSH receptor gene in infertile men with high serum FSH concentrations. Seventy male infertile patients with high FHS levels (> 12 mIU/ml) were screened for mutations in each of the 10 exons of the FSH receptor gene, using genomic DNA PCR and a single-strand conformation polymorphism (SSCP) analysis. From this study, three shifted bands were detected by SSCP. The first shifted band was found in the PCR product of exon 4, including the exon-intron boundary sequence in only one patient. The sequence analysis revealed a nucleotide A to T substitution in intron 3 (IVS3-4A-->T). The second shifted band was detected in exon 10 with high frequency (33%). A nucleotide A to G substitution was found at the position of the 994th nucleotide, predicting a Thr to Ala substitution at the position of the 307th amino acid (Thr307Ala). The third shifted band in the 3' region of exon 10 was detected frequently in infertile patient and normal groups. It was tightly linked to the Thr307Ala variant. Thus, all of the abnormalities represent neutral polymorphisms, and not pathological mutations of the FSH receptor gene. In conclusion, we did not confirm that the genomic mutation of the FSH receptor is a major genetic cause in Korean infertile patients with high FSH levels.

Nurses' assessment of postoperative pain: can it be an alternative to patients' self-reports?

This study was designed to evaluate whether the nurses' assessment of postoperative pain can be an alternative to patients' self-reporting. We examined 187 patients receiving postoperative intravenous patient-controlled analgesia. The nurses assessed the patients' pain with three pain indices (therapeutic efficacy, pain intensity, and facial pain expression) 8 hr after operation. The patients recorded their resting and movement pain using 100-mm visual analog scales immediately following the nurses' assessment. There was an acceptable correlation between overall pain measurement assessed by patients and that assessed by nurses (canonical correlation coefficient=0.72, p=0.0001). The resting pain was more reliably reflected than the movement pain in overall measurement assessed both by nurses and by patients. Among the three pain indices assessed by nurses, the pain intensity most reliably reflected the patients' self-reports. The pain intensity assessed with a simple verbal descriptor scale therefore is believed to be an effective alternative to the patients' self-reports of postoperative pain at rest. However, it mirrored the patients' self-reports during movement less reliably. Therapeutic efficacy and facial pain expression indices were not effective alternatives to patients' self-reporting.

Three functional isoforms of GAR-2, a Caenorhabditis elegans G-protein-linked acetylcholine receptor, are produced by alternative splicing

We have previously isolated a cDNA clone from Caenorhabditis elegans that encodes a novel form of G-protein-linked acetylcholine receptor, termed GAR-2. GAR-2 is similar to but pharmacologically distinct from muscarinic acetylcholine receptors. Here we report the identification of two gar-2 cDNA clones that are different from the previous one. These newly identified cDNAs encode polypeptides of 664 and 627 amino acids, whereas the previous one encodes a polypeptide of 614 amino acids. The three GAR-2 isoforms, which differ only in the third intracellular loop, arise from alternative splicing. Electrophysiological analyses using the Xenopus oocyte system showed that all three GAR-2 isoforms couple to the activation of G-protein-gated inwardly rectifying K+ (GIRK1) channel with similar drug specificity. Our results indicate that alternative splicing plays an important role in promoting molecular diversity of G-protein-linked acetylcholine receptors in C. elegans.

Effect of naringin supplementation on cholesterol metabolism and antioxidant status in rats fed high cholesterol with different levels of vitamin E

Some bioflavonoids are potent antioxidants and have pharmacological effects similar to those of vitamin E. The interactive effect of naringin and vitamin E was studied with respect to cholesterol metabolism and antioxidant status. Naringin supplementation (0.1%, wt/wt) with comparable levels of vitamin E was given to rats with a high-cholesterol (1%, wt/wt) diet for 5 weeks. The amount of vitamin E included in naringin-free and naringin diets was a low (low-E) and a normal (normal-E) level. The naringin supplementation significantly lowered the concentrations of plasma cholesterol and triglyceride compared to the naringin-free group in low vitamin E-fed rats. HMG-CoA reductase activity was significantly lowered by naringin supplementation within both the low-vitamin E group (794.64 +/- 9.87 vs. 432.18 +/- 12.33 pmol/min/mg protein, mean +/- SE; p < 0.05) and normal-vitamin E group (358.82 +/- 11.4 vs. 218.22 +/- 9.47 pmol/min/mg protein, mean +/- SE; p < 0.05) compared to each of the naringin-free group. The HMG-CoA reductase activity was also significantly lowered by increased dietary vitamin E when compared within the naringin and naringin-free group, respectively. Neither dietary naringin nor vitamin E did significantly change the activities of hepatic antioxidant enzymes and plasma thiobarbituric acid-reactive substance level. These data indicate that naringin lowers the plasma lipid concentrations when the dietary vitamin E level is low. The HMG-CoA reductase-inhibitory effect of naringin was more potent when dietary vitamin E was at a normal level. These data may contribute to understanding the interactive effect of naringin and vitamin E on cholesterol biosynthesis in high-cholesterol-fed rats.

Combination Chemotherapy of Oxaliplatin, 5-Fluorouracil, and Leucovorin in 5-Fluorouracil-Pretreated Patients with Metastatic Colorectal Cancer

PURPOSE

To evaluate the efficacy and toxicity of oxaliplatin in combination with 5-fluorouracil (5-FU) and leucovorin (LV) in patients with metastatic colorectal cancer who previously treated with 5-FU-based chemotherapy.

MATERIALS AND METHODS

Between April 1999 and January 2001, thirty-two patients were enrolled in this study. Oxaliplatin 130 mg/m2 was given intravenously (IV) on day 1 as was 5-FU 500 mg/m2 IV followed by continuous infusion of 5-FU 3,000 mg/m2 and LV 100 mg/m2 for 48 hours administered every 3 weeks. Six patients had received 5-FU as an adjuvant setting and 26 patients as a palliative regimen.

RESULTS

The median age of the patients was 50 years (range; 19-69) and the dominant sites of metastasis were the liver, lung or both in 9, 5 and 2 patients respectively. In 30 evaluable patients, the overall response rate was 27% including 1 complete response and 7 partial responses. The median response duration was 28 weeks (95% confidence interval; 22~34 weeks) and the median progression free survival of all patients was 24 weeks (95% confidence interval; 15~33 weeks). A median 5 cycles (range; 2~9) and total 155 cycles were performed in 32 patients. 150 cycles were evaluable for toxicity. The most common hematologic toxicity was grade 1~2 anemia in 78 cycles (52%). Leukopenia (39%) and thrombocytopenia (23%) were fully reversible. The most common non-hematologic toxicity was nausea/vomiting (43/30%) followed by diarrhea (23%), hepatotoxicity (21%) and neurotoxicity (21%). One patient ceased therapy due to grade 4 diarrhea. No other severe toxicity interrupted this treatment.

CONCLUSION

Oxaliplatin, 5-FU and LV in combination showed significant activity in previously treated metastatic colorectal cancer with favorable toxicity.

Effect of inhibitor of tumor necrosis factor-alpha on experimental otitis media with effusion

Tumor necrosis factor (TNF)-alpha is important in the pathogenesis of otitis media with effusion (OME). The purpose of this study was to determine the effect of TNF-alpha antagonist on the outcome of lipopolysaccharide (LPS)-induced OME in rats. Otitis media was induced by injecting Pseudomonas aeruginosa LPS transtympanically. Another (combination) group was pretreated with TNF-alpha antagonist, soluble TNF receptor type I (sTNF RI), before transtympanic injection of LPS. Saline and phosphate-buffered saline solutions were used as controls. Twelve hours after the transtympanic injection, otoscopic examination and aspiration of middle ear effusion (MEE) were done. The temporal bones in each group were examined histopathologically, and the vascular permeability of the middle ear mucosa was measured by the Evans blue vital dye technique. In the LPS and combination groups, MEE developed in 90% and 0% of ears, respectively. The combination group showed less inflammation, less mucosal thickening, and significantly decreased vascular permeability as compared to the LPS group. Transtympanic administration of sTNF RI appears to suppress the development of LPS-induced OME. This study suggests that TNF-alpha antagonist, along with antibiotics, may have an adjunctive role in the future treatment of MEE.

Iodide-to-cation charge-transfer bands as a novel probe for evaluation of actual acceptor strengths of cations in zeolites and cation-dependent pore volume change

Iodide-to-cation charge-transfer (ITC-CT) bands have been measured for the first time in zeolites X and Y exchanged with a series of alkali metal ions and the results show that the ITC-CT band progressively red shifts with increasing the size and the number of site III cations in the supercage, which indicates that the actual acceptor strength of the cation toward iodide increases with increasing the degree of protrusion of the cation into supercages and the number of cations, and overall, with decrease in supercage volume.

Sweet's syndrome during the treatment of acute promyelocytic leukemia with all-trans retinoic acid

All-trans retinoic acid (ATRA) is the standard induction treatment for acute promyelocytic leukemia (APL). Quite many ATRA-related side effects, including retinoic acid syndrome, were reported. So far, it has rarely been reported that Sweet's syndrome, characterized by fever, neutrophilia, painful erythematous cutaneous plaques, dense dermal infiltrates of mature neutrophils and rapid response to steroid therapy, is associated with ATRA. In the case that Sweet's syndrome associated with ATRA is found, physicians will have to face a great challenge over the possibility of infectious conditions. We present here a case of Sweet's syndrome associated with ATRA. A 35-year-old female with APL developed fever, painful erythematous cutaneous plaques on both cheeks, right wrist and both shins during induction chemotherapy with ATRA. A skin biopsy revealed a dense dermal infiltrate, consisting of mature neutrophils without vasculitis or cutaneous immunoglobulin deposits, which is compatible with Sweet's syndrome. Oral prednisone was administered and the lesions started to improve within 48 hours.

Molecular cloning and disruption of a novel gene encoding UDP-glucose: tetrahydrobiopterin alpha-glucosyltransferase in the cyanobacterium Synechococcus sp. PCC 7942

The gene encoding UDP-glucose:tetrahydrobiopterin alpha-glucosyltransferase (BGluT) was cloned from the genomic DNA of Synechococcus sp. PCC 7942. The encoded protein consisting of 359 amino acid residues was verified in vitro and in vivo to be responsible for the synthesis of tetrahydrobiopterin (BH4)-glucoside produced in the organism. The BGluT gene is the first cloned in pteridine glycosyltransferases and also a novel one cloned so far in UDP-glycosyltransferases. The mutant cells disrupted in the BGluT gene produced only aglycosidic BH4 at a level of 8.3% of the BH4-glucoside in wild type cells and exhibited half of the wild type growth in normal photoautotrophic conditions. These results suggest that the glucosylation of BH4 is required for the maintenance of the high cellular concentration of the compound, thereby supporting the normal growth of Synechococcus sp. PCC 7942.

Computerized analysis of fetal heart rate parameters by gestational age

OBJECTIVE

The aim of this study is to define the reference ranges for fetal heart rate (FHR) parameters according to gestational age, by determining the relationship between the FHR and gestational age using a computerized FHR analysis system.

METHODS

Using our own software developed by Hanyang University Hospital in Korea, non-stress tests were performed for 20 min. FHR parameters for 6455 subjects were analyzed for various gestational groups; <25 weeks, 25-28 weeks, 29-32 weeks, 33-36 weeks, 37-40 weeks, and >40 weeks.

RESULTS

The FHR parameters were related to gestational age. The mean baseline FHR, signal loss, and fetal movements decreased significantly with gestation (P<0.0001). The variability and accelerations of FHR were highest for the 37-40 weeks gestational group (P<0.05).

CONCLUSIONS

The results showed that overall, the differences in the FHR parameters between gestational groups were statistically significant, and the gestational age of the fetus should be considered when interpreting FHR patterns.

Different distribution of HLA class II alleles according to response to corticosteroid therapy in sudden sensorineural hearing loss

OBJECTIVE

To investigate the association of HLA class II alleles with the susceptibility to sudden sensorineural hearing loss and with the results of corticosteroid treatment in the Korean population.

DESIGN

HLA-DRB1, -DQA1, -DQB1, and -DPB1 genotyping by the sequence-specific oligonucleotide probes method in 41 patients with sudden sensorineural hearing loss and in 206 healthy control subjects. Initial hearing levels at the onset of hearing loss and final hearing levels after treatment were evaluated for the association with HLA class II alleles.

SETTING

Tertiary care referral center, ambulatory and hospitalized care.

SUBJECTS

Forty-one patients (24 men and 17 women; mean age, 49.2 years) were compared with 206 controls. Patients were divided into 2 groups according to their response to corticosteroid therapy (good response vs nonresponse).

RESULTS

The frequencies of HLA-DRB1, -DQA1, -DQB1, and -DPB1 alleles were not significantly different between patients and controls (P>.05). When an association between the results of corticosteroid treatment and the frequency of HLA alleles was evaluated, the frequencies of HLA-DRB1*14 (relative risk [RR] = 3.5, P<.02), -DQA1*03 (RR = 4.2, P<.02), and -DQA1*05 (RR = 3.1, P<.03) were significantly increased, but HLA-DQA1*01 (RR = 0.2, P<.004) and -DQB1*06 (RR = 0.2, P<.009) were decreased in the group nonresponsive to corticosteroid therapy, compared with the controls. The distribution of HLA-DQA1*01 (P<.04), -DQB1*06 (P<.02), and -DQA1*03 (P<.003) was significantly different between the responsive and the nonresponsive groups. HLA-DQA1 allelic combination analysis showed that the frequencies of DQA1*03 and *05 had a high RR value in patients with sudden sensorineural hearing loss (RR = 4.1, P<.003) and in patients in the nonresponsive group (RR = 8.9, P<.001), compared with the controls.

CONCLUSION

The presence of HLA class II alleles may be a useful genetic marker in forecasting a prognosis in Korean patients with sudden sensorineural hearing loss.

Enhanced cytotoxicity of doxorubicin encapsulated in liposomes with reconstituted Sendai F-proteins

Sendai F-virosomes, a novel type of liposome with reconstituted Sendai F-proteins, have been tested as a delivery system for various bioactive materials. However, encapsulation limitations and difficulties in controlling their constituents were drawbacks for further application to therapeutic purposes. We have tried to control virosomal constituents and have enhanced drug encapsulation efficiency into the virosomes. In vitro cytotoxicity of doxorubicin encapsulated in the F-virosomes were compared with free doxorubicin and doxorubicin in conventional liposomes. The F-virosomes were spontaneously prepared by detergent dialysis, a reconstitution process of Sendai F-proteins into liposomes. The reconstitution density of F-proteins affected the vesicle size of virosomes prepared by detergent dialysis; the larger amount of F-proteins made a smaller size of virosomes. There was little variation of size with time at physiological conditions, whilst the vesicle size of virosomes increased at acidic storage conditions (pH 5.5). Doxorubicin encapsulated in the F-virosomes exhibited a lower IC50 against B16BL6 mouse melanoma cells and Chang human hepatocarcinoma cells than that in conventional liposomes. The F-virosomes also exhibited higher cellular uptake than conventional liposomes. Addition of dioleoylphophatidylethanolamine, a fusogenic phospholipid, into the F-virosome further increased the cellular uptake as well as in vitro cytotoxicity. These types of virosome formulations can be clinically applicable as versatile vesicles for the efficient delivery of various therapeutic drugs, including genetic materials.

Supranormal differential renal function is real but may be pathological: assessment by 99m technetium mercaptoacetyltriglycine renal scan of congenital unilateral hydronephrosis

PURPOSE

It is unclear whether supranormal differential renal function of the hydronephrotic kidney is real or artifactual. We investigated the effect of clinical and renographic parameters on differential renal function.

MATERIALS AND METHODS

The study included 34 males and 10 females from 1 to 9 months old (median age 2.6 months) with unilateral congenital hydronephrosis. A 99mtechnetium (Tc) mercaptoacetyltriglycine (MAG3) scan was performed, and regions of interest were drawn on the kidneys, and perirenal and lateral backgrounds. Differential renal function was calculated with and without background subtraction at 30-second intervals from 0.5 to 3 minutes after injection of 99mTc-MAG3. The effects of age, sex, obstruction, site and size of the hydronephrotic kidney were analyzed using the generalized estimating equations method.

RESULTS

There were 11 right and 33 left hydronephrotic kidneys. An obstructive renographic pattern was present in 33 cases. The trends of differential renal function according to intervals were different between kidneys with and without background subtraction, and differential renal function increased significantly as size increased (p <0.05). Differential renal function of the hydronephrotic kidney with an obstructive renographic pattern increased with time when perirenal or no background subtraction was applied (p <0.05). The effects of age, sex or laterality on differential renal function were not significant. Supranormal function (differential renal function 55% or greater) was present regardless of background subtraction methods and measurement time.

CONCLUSIONS

Differential renal function is higher in larger hydronephrotic kidney but function of the kidney with an obstructive pattern is overestimated on later phases of 99mTc-MAG3 renal scan. Supranormal differential renal function is real and may be pathologic since it is prone to occur in larger obstructive hydronephrotic kidneys.

Effect of tumor necrosis factor-alpha on experimental otitis media with effusion

OBJECTIVES/HYPOTHESIS

Up to the present, many reports have demonstrated that local immune response is associated with maintenance and persistence of effusion in the middle ear cavity. Resulting retention of inflammatory cells and mediators in the middle ear results in ongoing effusion. The purpose of this study was to clarify the role of tumor necrosis factor in experimental otitis media with effusion, which was induced by transtympanic injection of tumor necrosis factor in the rats.

STUDY DESIGN

Four groups were designed in two experiments. The purpose of experiment 1 was to confirm that transtympanic injection of TNF-alpha produces the middle ear effusion. In experiment 2, TNFsolRI was used to evaluate the possibility as an inhibitor in otitis media with effusion.

METHODS

The histopathological changes were observed under light microscope, and the changes in microvascular permeability were examined using Evans blue vital dye technique.

RESULTS

Middle ear effusion was developed in 70% of specimens, and histopathological changes, such as subepithelial edema and marked infiltration of neutrophils, were present in 100% at 24 hours after administration of tumor necrosis factor-alpha through transtympanic approach. Extravasation of Evans blue dye was found in all specimens injected by tumor necrosis factor-alpha, which was qualified using a fluorescence microscope and quantified using a spectrophotometer. These histopathological findings and changes in microvascular permeability were significantly reduced by tumor necrosis factor soluble receptor type I.

CONCLUSIONS

Neutrophil infiltration, subepithelial edema, increased microvascular permeability, and resultant effusion were indirectly proved to be induced by tumor necrosis factor-alpha. We hope that this study may contribute to understanding the role of tumor necrosis factor-alpha in otitis media with effusion and clarifying the future role of tumor necrosis factor soluble receptor type I in preventing otitis media with effusion.

Supranormal differential renal function is real but may be pathological: assessment by 99m technetium mercaptoacetyltriglycine renal scan of congenital unilateral hydronephrosis

PURPOSE

It is unclear whether supranormal differential renal function of the hydronephrotic kidney is real or artifactual. We investigated the effect of clinical and renographic parameters on differential renal function.

MATERIALS AND METHODS

The study included 34 males and 10 females from 1 to 9 months old (median age 2.6 months) with unilateral congenital hydronephrosis. A 99mtechnetium (Tc) mercaptoacetyltriglycine (MAG3) scan was performed, and regions of interest were drawn on the kidneys, and perirenal and lateral backgrounds. Differential renal function was calculated with and without background subtraction at 30-second intervals from 0.5 to 3 minutes after injection of 99mTc-MAG3. The effects of age, sex, obstruction, site and size of the hydronephrotic kidney were analyzed using the generalized estimating equations method.

RESULTS

There were 11 right and 33 left hydronephrotic kidneys. An obstructive renographic pattern was present in 33 cases. The trends of differential renal function according to intervals were different between kidneys with and without background subtraction, and differential renal function increased significantly as size increased (p <0.05). Differential renal function of the hydronephrotic kidney with an obstructive renographic pattern increased with time when perirenal or no background subtraction was applied (p <0.05). The effects of age, sex or laterality on differential renal function were not significant. Supranormal function (differential renal function 55% or greater) was present regardless of background subtraction methods and measurement time.

CONCLUSIONS

Differential renal function is higher in larger hydronephrotic kidney but function of the kidney with an obstructive pattern is overestimated on later phases of 99mTc-MAG3 renal scan. Supranormal differential renal function is real and may be pathologic since it is prone to occur in larger obstructive hydronephrotic kidneys.

Effect of thyroid hormone on the alcohol dehydrogenase activities in rat tissues

The effects of thyroid hormone on hepatic and gastric alcohol dehydrogenase (ADH) activities (nM of NADH/min/mg of cytosolic protein) have been investigated in male Sprague Dawley rats treated with thyroxine (1 mg/kg, po) for 14 days. Whereas hepatic ADH activity in thyroxine-treated rats decreased by 61.3% of control rats (26.4 vs 43.2, p<0.001), gastric ADH activity increased by 262.9% of control rats (4.9 vs 1.9, p<0.001). As for the activities of the lung and kidney, thyroxine treatment did not produce any statistically significant changes. These data suggest that thyrotoxicosis causes a decrease of hepatic alcohol metabolism, and that the increase of gastric ADH activity in thyrotoxic rats can partly restore the first-pass metabolism of ethanol.

A novel silent substitution (C8516T) in exon 9 of the human PROC gene

Protein C is a vitamin K dependent serine protease zymogen, which has a regulatory influence over the coagulation cascade via the inhibition of factors Va and VIIIa. Hereditary protein C deficiency is associated with an increased risk of thromboembolic disease. A multitude of families displaying protein C (PROC) gene defects have been reported, and a number of DNA sequence polymorphisms are known to occur in the PROC gene. We have identified a previously undescribed silent substitution (C8516T) by direct DNA sequencing in a Korean patient with thrombosis and protein C deficiency. In addition, a rare T allelic frequency (0.016) was determined in 123 patients with acquired or hereditary protein C deficiency.

Electrophysiological characteristics of rat gustatory cyclic nucleotide--gated channel expressed in Xenopus oocytes

The complementary DNA encoding gustatory cyclic nucleotide--gated ion channel (or gustCNG channel) cloned from rat tongue epithelial tissue was expressed in Xenopus oocytes, and its electrophysiological characteristics were investigated using tight-seal patch-clamp recordings of single and macroscopic channel currents. Both cGMP and cAMP directly activated gustCNG channels but with markedly different affinities. No desensitization or inactivation of gustCNG channel currents was observed even in the prolonged application of the cyclic nucleotides. Single-channel conductance of gustCNG channel was estimated as 28 pS in 130 mM of symmetric Na(+). Single-channel current recordings revealed fast open-close transitions and longer lasting closure states. The distribution of both open and closed events could be well fitted with two exponential components and intracellular cGMP increased the open probability (P(o)) of gustCNG channels mainly by increasing the slower opening rate. Under bi-ionic conditions, the selectivity order of gustCNG channel among divalent cations was determined as Na(+) approximately K(+) > Rb(+) > Li(+) > Cs(+) with the permeability ratio of 1:0.95:0.74:0.63:0.49. Magnesium ion blocked Na(+) currents through gustCNG channels from both intracellular and extracellular sides in voltage-dependent manners. The inhibition constants (K(i)s) of intracellular Mg(2+) were determined as 360 +/- 40 microM at 70 mV and 8.2 +/- 1.5 mM at -70 mV with z delta value of 1.04, while K(i)s of extracellular Mg(2+) were as 1.1 +/- 0.3 mM at 70 mV and 20.0 +/- 0.1 microM at -70 mV with z delta of 0.94. Although 100 microM l-cis-diltiazem blocked significant portions of outward Na(+) currents through both bovine rod and rat olfactory CNG channels, the gustCNG channel currents were minimally affected by the same concentration of the drug.

Clinical impacts of tumor cell contamination of hematopoietic stem cell products in metastatic breast cancer patients undergoing autologous peripheral blood stem cell transplantation: multicenter trial

To determine whether the tumor cell contamination of peripheral blood stem cells influences clinical impacts on high-dose chemotherapy in patients with metastatic breast cancer, we analyzed carcinoembryonic antigen (CEA) mRNA in the apheresis products by nested RT-PCR (reverse transcriptase-polymerase chain reaction). A total of 38 metastatic breast cancer patients and ten normal healthy subjects as a negative control were included. Twenty out of 38 (51.3%) apheresis products from patients with metastatic breast cancer were positive for CEA mRNA. CEA mRNA was noted in 54.8% (17/31) of patients mobilized with chemotherapy plus G-CSF and 42.8% (3/7) of patients with G-CSF alone. There was no significant difference in age, estrogen receptor, menopausal status, mobilization method, disease free interval, or number of metastasis sites (1 vs > or = 2) between positive and negative groups. The presence of CEA mRNA in apheresis products did not influence the time to progression and overall survival in both groups. However, both the univariate and the multivariate analysis disclosed that the number of metastasis was associated with survival significantly. We suggest that the tumor cell contamination does not predict poor treatment outcome in patients with metastatic breast cancer.

Transracial evidence for the influence of the homologous HLA DR-DQ haplotype on transmission of HLA DR4 haplotypes to diabetic children

The HLA-DQB1*0302 allele on DR4 haplotypes is a marker for type 1 diabetes susceptibility and it is an especially high-risk allele in DR3/4 because of its preferential distribution in Caucasian DR3/4 patients. In Asians, not only DQB1*0302 but also DQB1*0401 on DR4 haplotypes are associated with type 1 diabetes. We investigated whether the contribution of these DQ molecules was also genotype-dependent in Asians. Although the prevalence of the DR4-DQB1*0302 haplotype did not differ in patients vs. controls, the DR3/4-DQB1*0302 genotype had a RR of 12 (P<10(-4)). Moreover, a significant association of DQB1*0302 with the DR3/4 genotype was found (RR=3, P<10(-2)). In contrast, the distribution of DQB1*0401 alleles of DR4/X (X: other than 3, 4) is different from that of DR3/4 and DR4/4. Especially a significant association of DQB1*0401 with DR4/X (X: other than 1, 3, 4) was found (RR=3, P<10(-3)). The frequency of transmission of the DR4-DQB1*0302 haplotypes to diabetic offspring with DR3 was 80%, while to those without DR3 was 40%. In contrast, the transmission of the DR4-DQB1*0401 to those with DR3 was 60%, while to those without DR3 was 80%. High-risk DR4 subtypes were predominant in DR4/X (RR=7, P<10(-3)), whereas protective DR4 subtypes were observed mainly in the DR3/4 (RR=3, P<0.05). The association with diabetes and transmission to a diabetic offspring of DR4 haplotypes varies depending on the haplotype borne on the homologous chromosome. This might contribute not only to the synergistic effect of DR3/4, but also to the susceptibility influence of HLA DQB1*0401 alleles confined to DR4/X.

Response to high-dose intravenous immune globulin as a valuable factor predicting the effect of splenectomy in chronic idiopathic thrombocytopenic purpura patients

This study was conducted to verify whether the response to high-dose intravenous immune globulin (IVIG) was related to the effect of splenectomy in chronic idiopathic thrombocytopenic purpura (ITP) patients. A total of 79 patients over 16 years of age were enrolled in this study. The response to the treatment was classified on the basis of the platelet count as no response (NR, <50 x 10(9)/l), incomplete response (IR, (50-150) x 10(9)/l), and complete response (CR, >150 x 10(9)/l). The response was evaluated after the infusion of high-dose IVIG, within 2 weeks after splenectomy (immediate response), and during a follow-up period of more than 6 months after splenectomy (sustained response), respectively. 58 patients (73.4%) showed responses (CR or IR) to high-dose IVIG. After splenectomy, immediate responses were observed in 73 patients (92%). The response to high-dose IVIG had no relationship with the immediate response to splenectomy (P = 0.333). A follow-up evaluation was possible with 58 patients; 6 patients with NR in immediate responses did not show any response during the follow-up period, and 17 patients relapsed within 6 months after immediate responses, so 35 patients (60.3%) had sustained responses. Responders to IVIG had significantly higher sustained response rates to splenectomy than non-responders (62% vs. 38%, P = 0.001). These results indicate that the response to high-dose IVIG could be a valuable factor predicting the sustained response to splenectomy in chronic ITP patients.

Purification and kinetic characterization of CTP:phosphocholine cytidylyltransferase from Saccharomyces cerevisiae

CTP:phosphocholine cytidylyltransferase (CCT) regulates the biosynthesis of phosphatidylcholine in mammalian cells. In order to understand the mechanism by which this enzyme controls phosphatidylcholine synthesis, we have initiated studies of CCT from the model genetic system, the yeast Saccharomyces cerevisiae. The yeast CCT gene was isolated from genomic DNA using the polymerase chain reaction and was found to encode tyrosine at position 192 instead of histidine, as originally reported. Levels of expression of yeast CCT activity in Escherichia coli or in the yeast, Pichia pastoris, were somewhat low. Expression of yeast CCT in a baculovirus system as a 6x-His-tag fusion protein was higher and was used to purify yeast CCT by a procedure that included delipidation. Kinetic characterization revealed that yeast CCT was activated approximately 20-fold by 20 microM phosphatidylcholine:oleate vesicles, a level 5-fold lower than that necessary for maximal activation of rat CCT. The k(cat) value was 31.3 s(-1) in the presence of lipid and 1.5 s(-1) in the absence of lipid. The K(m) values for the substrates CTP and phosphocholine did not change significantly upon activation by lipids; K(m) values in the presence of lipid were 0.80 mM for phosphocholine and 1.4 mM for CTP while K(m) values in the absence of lipid were 1.2 mM for phosphocholine and 0.8 mM for CTP. Activation of yeast CCT, therefore, appears to be due to an increase in the k(cat) value upon lipid binding.