The 1995 Moyer Award. The effect of burn injury on allograft rejection, alloantigen processing, and cytotoxic T-lymphocyte sensitization

Burn injury impairs cellular immunity, increases the risk of viral infection, and delays allograft rejection, but little is known about its effect on antigen processing and cytotoxic T-lymphocyte (CTL) function. This study examined the effect of burn injury on alloantigen sensitization with an in vivo model of second-set rejection and in vitro assays of CTL alloreactivity. Anesthetized CBA mice (n = 95) received a 0%, 20%, or 40% full-thickness contact burn that was partially excised 3 days later and covered with autograft or C57BL/6 allograft. Two weeks after the burn was inflicted, mice were challenged with second-set tail allografts, which were observed for rejection. Median graft survival times were compared by Wilcoxon rank and chi-squared analysis. Additional CBA mice (n = 24) underwent similar burn injury, excision, and grafting. Splenocytes were harvested 2 weeks later and were used as CTL effectors against radiolabeled targets. Dilution curves of target lysis were compared by analysis of variance. Forty percent burn injury prolonged unprimed allograft survival from 13 to 15 days (p < 0.01) but had a greater effect on primed allograft survival, which increased from 9 to 12.5 days (p < 0.01). Furthermore, a 40% burn eliminated the influence of priming, resulting in second-set graft survival similar to that of mice in an unburned, unprimed control group (12.5 vs. 13 days, NS). Whereas 20% burn injury did not inhibit CTL priming, a 40% burn profoundly impaired CTL function (p < 0.001), which recovered only after 6 days of in vitro allostimulation. Burn injury inhibits both alloantigen priming and the immunologic memory of CTLs as a function of burn size. This impairment in alloantigen processing helps to explain defects in cellular immunity and suggests a mechanism for prolonged allograft survival and decreased viral resistance after burn injury occurs.

Anterior extension of acute pancreatitis: CT findings

OBJECTIVE

The purpose of this study is threefold: (a) to specify the pathway of the extension of pancreatitis to the anterior abdominal wall, which is clinically famous as the Cullen sign; (b) to assess if this pattern of involvement affects a patient's prognosis; and (c) to seek its association with the inflammatory processes that take place in the vicinity of the pancreatic head.

MATERIALS AND METHODS

The CT findings of 277 patients with acute pancreatitis were retrospectively reviewed.

RESULTS

Inflammatory changes involved the anterior abdominal wall in 5 of 277 cases (1.8%) with acute pancreatitis. Inflammatory processes seemed to have been delivered to the anterior abdominal wall from the pancreatic head and the hepatoduodenal ligament and along the falciform ligament. The probable triggers of acute pancreatitis in such cases were endoscopic retrograde cholangiopancreatography in two cases, alcohol intake in one case, and one case unknown. Three of five cases had proven or suspected choledocholithiasis or cholelithiasis. All five patients got well after proper treatments for acute pancreatitis.

CONCLUSION

The results of our review suggest that the anterior extension of acute pancreatitis does not directly mean extensive retroperitoneal involvement of the phlegmon or pseudocysts nor fatal prognosis either and that this style of extension might be associated with inflammatory processes that occur around the pancreatic head.

[Effect of reimplantation response on recipient pulmonary hemodynamics in single lung transplantation]

Until now, reimplantation response (RR) has been thought to be a transient dysfunction of the transplanted lung in single lung transplantation. How does RR influence on the native lung in single lung transplantation? We studied the influence of RR to the native lung with 20 dogs which were divided separated into 3 groups. In group I (6 dogs) and II (6), left lung allotransplantation without immunosuppression was performed. In group II, PGI2 was administered to the donors at 1 microgram/kg/min for 60 minutes iv drip infusion during lung extraction and super oxide dismutase (SOD) was administered to the recipients at 20 mg/kg just before reperfusion of the transplanted lung. In group III (8), allotransplantation with immunosuppression (CYA 20 mg/kg, AZ 4 mg/kg) was done using PGI2 and SOD in the same way as group II. In all groups doppler flow probes were attached to the ascending aorta and left pulmonary artery. For over 1 week, pulmonary hemodynamics was evaluated. In group I pulmonary arterial pressure increased up to 38.7 +/- 19.7 mmHg on 3 postoperative day, which showed significant difference (p < 0.05) from group II. An increase in vascular resistance of the transplanted lung was recognized right after transplantation in the both groups (0.212 +/- 0.058 mmHg/ml/kg to 0.487 +/- 0.114 in group I, 0.207 +/- 0.072 to 0.407 +/- 0.172 in group II). However, vascular resistance of the right lung increased in group I against group II right after transplantation (0.182 +/- 0.116 to 0.367 +/- 0.195 in group I, 0.183 +/- 0.116 to 0.214 +/- 0.149 in group II), which showed significant difference (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Ethanol decreases the levels of GLUT2 glucose transporter mRNA in hepatocytes

In order to elucidate the implication of GLUT2 in the impaired glucose metabolism caused by ethanol, we examined if ethanol affects GLUT2 glucose transporter mRNA expression in the liver. After the adult rats were fed with and/or without ethanol for 1 or 4 weeks, hepatocytes were isolated and total RNA was extracted from them. The levels of GLUT2 mRNA in hepatocytes isolated from 1 week-ethanol fed rats estimated by Northern blot analysis did not change compared to those of untreated rats, those levels in hepatocytes from 4 weeks-ethanol fed rats decreased markedly. Studies were also performed using primary rat hepatocyte cultures in vitro. We found that ethanol, when added to cultured hepatocytes, resulted in a substantial reduction in the levels of GLUT2 mRNA and this effect was only observed after 24 hr exposure of ethanol. Thus, ethanol seems to have a direct inhibitory effect on GLUT2mRNA in the liver, which may eventually cause the impaired glucose tolerance.

Modifications of neurofilament proteins by possible metabolites of allyl chloride in vitro

Chronic exposure to allyl chloride (ALL) is known to produce a central-peripheral distal axonopathy. In relation to the mechanism(s), the present study was conducted to examine the abilities of ALL and its putative metabolites, i.e., epichlorohydrin, glycerol alpha-monochlorohydrin, allyl alcohol and acrolein to cross-link proteins in vitro. Neurofilament-riched cytoskeletal proteins (1mg/ml) and ovalbumin (10mg/ml) were incubated with 160 mM tested chemicals except for acrolein at 0.5 mM and 1 mM. Time-dependent studies by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) revealed that not only ALL, but also acrolein and epichlorohydrin exerted chemical modifications on axonal cytoskeletal proteins; while only acrolein-treated ovalbumin could manifest evidence of polymerization of the protein. Immunoblotting of PAGE-separated proteins confirmed that the high molecular weight proteins on the top of SDS-PAGEs were NF antigen-contained covalent cross-linked materials.

Interrelation of differentiation, proliferation and apoptosis in cancer cells

Treatment of human leukemia HL-60 cells with ceramide, a breakdown product of sphingomyelin, induced both programmed cell death ("apoptosis"), and cellular differentiation. Apoptosis in response to ceramide occurred in a concentration-dependent manner. Apoptosis induced by ceramide in HL-60 cells requires the presence of c-jun protooncogene. However apoptosis is inhibited by curcumin, a specific inhibitor of c-jun/AP-1. Whereas curcumin restores ability of inhibited cells to grow, it does not affect ceramide-induced differentiation. These results indicate that ceramide controls cell differentiation and proliferation through apoptosis by activating the nuclear transcriptional factor AP-1. Further, AP-1 is apparently more closely related to apoptosis-inducing signal transduction pathway than to the pathway leading to cellular differentiation.

Induction of anti-tumor immunity by mouse tumor cells transfected with mouse interleukin-12 gene

Interleukin-12 (IL-12) is a heterodimeric cytokine. In order to transduce both cDNAs for p35 and p40 of IL-12 in the tumor cells, a polycistronic retroviral vector was constructed by inserting the internal ribosome entry site gene of encephalomyocarditis virus between two cDNAs. On the other hand, two cDNAs were sequentially transfected in the tumor cells. Both polycistronic gene transfectants and double transfectants produced biologically active mouse IL-12. IL-12-expressing tumor cells were all rejected in syngeneic mice, and induced cytotoxic T lymphocyte activity. The capacity to induce anti-tumor memory may depend on the amount of IL-12 produced by the transfectants, because the relatively higher IL-12 producer tumor cell line induced the anti-tumor memory in the rejected mice, but the lower producer did not.

Nucleotide sequence and regulation of a new putative cell wall hydrolase gene, cwlD, which affects germination in Bacillus subtilis

DNA sequencing of a region upstream of the mms223 gene of Bacillus subtilis showed the presence of two open reading frames, orf1 and orf2, which may encode 18- and 27-kDa polypeptides, respectively. The predicted amino acid sequence of the latter shows high similarity to a major autolysin of B. subtilis, CwlB, with 35% identity over 191 residues, as well as to other autolysins (CwlC, CwlM, and AmiB). The gene was tentatively named cwlD. Bright spores produced by a B. subtilis mutant with an insertionally inactivated cwlD gene were committed to germination by the addition of L-alanine, and spore darkening, a slow and partial decrease in A580, and 72% dipicolinic acid release compared with that of the wild-type strain were observed. However, degradation of the cortex was completely blocked. Spore germination of the cwlD mutant measured by colony formation after heat treatment was less than 3.7 x 10(-8). The germination deficiency of the cwlD mutant was only partially removed when the spores were treated with lysozyme. Analysis of the chromosomal transcription of cwlD demonstrated that a transcript (RNA2) appearing 3 h after initiation of sporulation may have originated from an internal sigma E-dependent promoter of the cwlD operon, and a longer transcript (RNA1) appearing 4.5 h after sporulation may have originated from a sigma G-dependent promoter upstream of the orf1 gene. The cwlD mutant harboring a B. subtilis vector plasmid containing the intact cwlD gene recovered germination at a frequency 26% of the wild-type level.

[A case of Acanthamoeba keratitis after operation for cataract]

Acanthamoeba keratitis occurs mainly in contact lens users. We experienced a patient with Acanthamoeba keratitis after operation for cataract. A 70-year-old male, who suffered from suppurative keratitis with impairment of visual acuity and eye pain in the left eye after the operation, was admitted to our hospital. After admission he received treatment with oral and topical antibiotics without any improvement. Neither bacterial or fungal pathogens was detected from corenal skrappings. Blue stained Acanthamoeba cysts were detected with the Parker ink KOH preparation from punctured fluid of the anterior chamber of the eye. Acanthamoeba cysts were also cultured on a nonnurient agar plate with Escherichia coli. Then he was treated with oral and topical miconazole and topical fluconazole. His visual acuity did not improve because of the lag of appropriate treatment. Therefore, attention must be paid for the existence of Acanthamoeba keratitis after ophthalmologic operations.

Transfer of Streptococcus adjacens and Streptococcus defectivus to Abiotrophia gen. nov. as Abiotrophia adiacens comb. nov. and Abiotrophia defectiva comb. nov., respectively

We performed this study to determine the 16S rRNA sequences of the type strains of Streptococcus adjacens and Streptococcus defectivus and to calculate the phylogenetic distances between these two nutritionally variant streptococci (NVS) and other members of the genus Streptococcus. S. adjacens and S. defectivus belonged to one cluster, but this cluster was not closely related to other streptococcal species. A comparative analysis of the sequences of these organisms and other low-G+C-content gram-positive bacteria revealed that the two NVS species formed a distinct cluster and were only remotely related to the Aerococcus and Carnobacterium clusters. The highest level of homology (93.7%) was found between S. adjacens and Carnobacterium divergens. Carnobacterium species have meso-diaminopimelic acid in their cell walls, but S. adjacens and S. defectivus have L-lysine as the diamino acid at position 3 in their peptidoglycan tetrapeptides. On the basis of our findings and the results of previous phenotypic studies, we propose that the NVS species should be placed in a new genus, the genus Abiotrophia, as Abiotrophia adiacens comb. nov. and Abiotrophia defectiva comb. nov.

Kinetic analysis of T cells and antibody production in chickens infected with Marek's disease virus

In chickens inoculated with a Marek's disease (MD) vaccine and subsequently with virulent MD virus (MDV), CD4+ T cell population was drastically decreased following a transient increase at 21 days after hatching (16 days after MDV infection). To elucidate the immune response after the decrease of CD4+ T cell population, the antibody production against sheep red blood cells (SRBC) was examined in these chickens. Chickens challenged with a virulent MDV after MD vaccination produced lower titers, of anti-SRBC antibody than untreated control chickens. Antibody production against SRBC was also lowered in vaccinated chickens or chickens challenged with a virulent MDV.

Autoantibodies to glutamic acid decarboxylase in patients with autoimmune thyroid disease: relation to competitive insulin autoantibodies

We evaluated the presence of autoantibodies to glutamic acid decarboxylase (GAD), competitive insulin autoantibodies (IAA) and islet cell antibodies (ICA) in sera from 288 non-diabetic patients with autoimmune thyroid disease (AITD), including 212 patients with Graves' disease and 76 with Hashimoto's thyroiditis, and in 235 age- and sex-matched healthy control subjects. GAD antibodies and IAA were assayed using radioimmunoassay with 125I-labelled purified pig brain GAD and human insulin, respectively. Titers of greater than 4.7 units for GAD antibodies and 50 nU/ml for IAA, respectively, the mean + 3SD of 235 age- and sex-matched healthy individuals, were defined as positive. The mean titers of GAD antibodies in patients with Graves' disease and in patients with Hashimoto's thyroiditis were 3.6 +/- 4.6 (mean +/- SD, range 0.6-52.0) units and 3.2 +/- 1.4 (range 0.6-10.0) units, respectively. Titer of GAD antibodies in patients with AITD was significantly higher than in healthy controls (P < 0.0005). Thirteen of 212 (6.1%) patients with Graves' disease and 6 of 76 (7.9%) patients with Hashimoto's thyroiditis had positive GAD antibody titers, whereas titers in healthy control sera were < 4.7 units in all but two individuals (P < 0.005). In competition analysis with purified unlabelled GAD, binding tracer was inhibited in all of 13 GAD antibody-positive Graves' sera and 5 of 6 GAD antibody-positive sera from patients with Hashimoto's thyroiditis. Eight of 212 (3.8%) patients with Graves' disease and 3 of 76 (3.9%) patients with Hashimoto's thyroiditis, but none of healthy controls had IAA levels exceeding the range for normal controls (P < 0.005). Positive IAA levels ranged between 50 and 2383 nU/ml. Strikingly, all of 19 GAD antibody-positive sera were negative for IAA. ICA were not detected in any of the patients or healthy controls. These data demonstrate that GAD antibodies in sera of AITD patients are of low titer but significantly elevated compared to healthy controls, and are independent of the appearance of IAA. They also indicate that, in patients with AITD, an autoimmune response to GAD may occur with no relationship to production of IAA.

[Clinical usefulness of helical-scanning CT for the evaluation of arteriosclerotic carotid lesions]

We examined arteriosclerotic carotid lesions in 76 patients using helical scanning CT (HES-CT), and evaluated the clinical usefulness of this method. A high speed slip-ring X-ray CT system was used. Scanning of the neck was performed for a 30 second period following intravenous bolus injection of non-ionic contrast medium, while couch top movement was 2.0 mm/sec. Multiplannar reconstruction images (MPR-image) and 3-dimensional surface images (3D-image) were reconstructed from the continuous raw data. MPR-images offered axial, coronal and sagittal images in which the lesion could be seen from any direction, and 3D-images that could be freely rotated were obtained by using a track ball and monitor. Eighteen cases were also evaluated by conventional angiography. Excellent HES-CT images were obtained in 73 cases, showing occlusion in 13, stenosis in 34, plaques without calcification in 15 and plaques with calcification in 74 vessels. A good correlation was obtained between HES-CT and angiogram in most cases, and in 6 cases, HES-CT was superior in the detection of stenosis, because it enabled us to observe the lesion from various directions. These results suggested that HES-CT was a minimally invasive, useful diagnostic method for the evaluation of arteriosclerotic carotid disease.

Activation of phospholipase D by prostaglandin F2 alpha in rat luteal cells and effects of inhibitors of arachidonic acid metabolism

In rat luteal cells labeled with [3H]oleic acid, PGF2 alpha-stimulated phospholipase D (PLD) activation was investigated. The PLD activity was detected by measuring the accumulation of [3H]phosphatidylethanol (PtdEt) in the presence of ethanol. PGF2 alpha stimulated PtdEt accumulation at concentrations of more than 100 nM in the presence of ethanol. However, PtdEt accumulation did not change in the absence of ethanol. PGF2 alpha (1 microM) increased PtdEt accumulation after 1 min, and the accumulation reached a plateau by 2-3 min. These results indicate that PGF2 alpha activates PLD in rat luteal cells. U-73122, a phospholipase C (PLC) inhibitor, and staurosporine, a protein kinase C (PKC) inhibitor, did not inhibit PGF2 alpha-stimulated [3H]PtdEt accumulation. These results suggest that PGF2 alpha-induced PLD activation is different from PLC-PKC systems. We reported previously that PGF2 alpha stimulated the release of arachidonic acid. The effects of indomethacin, nordihydroguaiaretic acid (NDGA), and 5,8,11,14-eicosatetraynoic acid (ETYA), inhibitors of arachidonic acid metabolism, on PGF2 alpha-stimulated PtdEt accumulation were examined. Pretreatment with indomethacin enhanced PGF2 alpha-induced PtdEt accumulation. In contrast, pretreatment with NDGA and ETYA inhibited PGF2 alpha-induced PtdEt accumulation. It is suggested that PGF2 alpha-stimulated PLD activation is mediated via lipoxygenase products.

Effect of atropine on cyanide-induced acute lethality in mice

The effects of atropine on acute lethality induced by cyanide were investigated in mice. The LD50 value of cyanide (s.c. injection) was 8.4 (7.6-9.3) mg/kg. However, the LD50 value of cyanide (s.c.) was significantly increased by 1.5-fold when atropine (32 mg/kg) was injected s.c. in mice. Furthermore, the combined administration of atropine (32 mg/kg), Ca2+ (500 mg/kg) and sodium thiosulfate (1 g/kg) tremendously increased the LD50 value by 5.6-fold in mice although sodium thiosulfate or Ca2+ alone increased the LD50 2.5- or 1.5-fold. On the other hand, although the LD50 value of cyanide (intracerebroventricular injection (i.v.t.)) was 52.0 (47.4-57.0) micrograms/brain, the LD50 value of cyanide (i.v.t.) was significantly increased by 1.3- or 1.61-fold in mice 10 min after s.c. injection of atropine (32 mg/kg) or Ca2+ (500 mg/kg). Furthermore, the combined administration of atropine and Ca2+ increased the LD50 value of cyanide by 2.1-fold. These results suggest that atropine inhibits cyanide-induced acute lethality and promotes the antagonistic effect of thiosulfate and Ca2+ in mice.

Lower leg fracture with Parkes-Weber syndrome complicated by disseminated intravascular coagulation

Reports of Parkes-Weber syndrome complicated by disseminated intravascular coagulation (DIC) are rare in the orthopaedic literature. This is a case report of a 23-year-old man who had this syndrome and who sustained a lower-leg fracture complicated by the DIC. Open reduction was not attempted because the DIC worsened after manual reduction. Amputation was rejected by the patient. Three months of continuous infusion of heparin and replacement therapy with fresh frozen plasma was done. Cast immobilization without further reductions was continued. The DIC improved and union of the fractures was observed at 2 years and 3 months after injury.

Reversal of drug sensitivity in MDR subline of P388 leukemia by gene-targeted antisense oligonucleotide

We attempted to reverse multidrug resistance (MDR) by treatment with 25-mer antisense phosphorothioate oligonucleotide. The phosphorothioate analogs, the sequences of which are sense or antisense to the initiation codon of mouse mdr1 mRNA, were tested against murine leukemic P388/S and adriamycin-resistant P388/ADR cell lines. A weak inhibitory effect on the growth of P388/S and P388/ADR cells was observed at a sense and antisense oligonucleotide concentration of 30 microM. Using the monoclonal antibody to P-glycoprotein and a flow cytometry technique, we showed that the level of expression of P-glycoprotein in P388/ADR cells treated with antisense oligonucleotide was lower than when treated with sense oligonucleotide. The antisense oligonucleotide potentiated the growth-inhibitory effect of vinblastine on P388/ADR cells, whereas sense oligonucleotide did not. This was accompanied by an increase in vinblastine retention in the cells. The reversal of the resistance by antisense oligonucleotide was increased by the combination with 1 microM verapamil. These results suggest that the antisense oligonucleotide and low dose verapamil may be useful in circumventing the resistance to anticancer drugs of MDR tumors.

[Treatment of secondary hyperparathyroidisms of predialysis chronic renal failure with low doses of 1.25(OH)2D3]

Although disorders of renal calcitriol synthesis play an important role in the pathogenesis of secondary hyperparathyroidism in the early and moderate phase of chronic renal failure, the treatment of secondary hyperparathyroidism with vitamin D metabolite has not attained consensus from the view point that is accelerates the progression of renal disease. The aim of this study was to evaluate the efficacy and adverse effect of low-dose daily oral treatment of 1.25 vitamin D for patients with mild to moderate renal failure. Fifteen chronic renal failure patients with serum creatinine ranging from 2.5 to 6.1 mg/dl and serum intact parathyroid hormone ranging from 100 to 450 pg/ml, were treated with oral 0.25-0.5 micrograms of 1.25 vitamin D for six months, after a six month control periods. In the six months control periods, serum intact parathyroid hormone, alkaline phosphatase activity, and bone gla protein increased significantly, however after the treatment of 1.25 vitamin D, serum intact parathyroid hormone, alkaline phosphatase activity, and bone gla protein decreased significantly. Serum calcium concentration increased significantly after the initiation of 1.25 vitamin D treatment, so it could not be ascertained whether or not 1.25 vitamin D directly suppressed parathyroid hormone synthesis. Bone mineral densities did not change within one year. Renal function was evaluated from the slopes of the reciprocal serum creatinine concentration versus time. The slopes did not change after the administration of 1.25 vitamin D. In conclusion, 1.25 vitamin D treatment of secondary hyperparathyroidism in patients with mild to moderate renal failure had beneficial therapeutic effect on humoral bone parameters, and did not show any adverse effect on renal function.

Endothelin 1 stimulates Na+,K(+)-ATPase and Na(+)-K(+)-Cl- cotransport through ETA receptors and protein kinase C-dependent pathway in cerebral capillary endothelium

The effect of endothelins (ET-1 and ET-3) on 86Rb+ uptake as a measure of K+ uptake was investigated in cultured rat brain capillary endothelium. ET-1 or ET-3 dose-dependently enhanced K+ uptake (EC50 = 0.60 +/- 0.15 and 21.5 +/- 4.1 nM, respectively), which was inhibited by the selective ETA receptor antagonist BQ 123 (cyclo-D-Trp-D-Asp-Pro-D-Val-Leu). Neither the selective ETB agonists IRL 1620 [N-succinyl-(Glu9,-Ala11,15)-ET-1] and sarafotoxin S6c, nor the ETB receptor antagonist IRL 1038 [(Cys11,Cys15)-ET-1] had any effect on K+ uptake. Ouabain (inhibitor of Na+,K(+)-ATPase) and bumetanide (inhibitor of Na(+)-K(+)-Cl- cotransport) reduced (up to 40% and up to 70%, respectively) the ET-1-stimulated K+ uptake. Complete inhibition was seen with both agents. Phorbol 12-myristate 13-acetate (PMA), activator of protein kinase C (PKC), stimulated Na+,K(+)-ATPase and Na(+)-K(+)-Cl- cotransport. ET-1- but not PMA-stimulated K+ uptake was inhibited by 5-(N-ethyl-N-isopropyl)amiloride (inhibitor of Na+/H+ exchange system), suggesting a linkage of Na+/H+ exchange with ET-1-stimulated Na+,K(+)-ATPase and Na(+)-K(+)-Cl- cotransport activity that is not mediated by PKC.

Mutations of the basic amino acid transporter gene associated with cystinuria

To investigate the function of a basic and neutral amino acid transporter-like protein (rBAT) which is a candidate gene for cystinuria, we analysed the rBAT gene in cystinuric patients. Patient 1 is a compound heterozygote with mutations in the rBAT gene causing a glutamine-to-lysine transition at amino acid 268, and a threonine-to-alanine transition at amino acid 341, who inherited these alleles from his mother (E268K) and father (T341A), respectively. Injection of T341A and E268K mutant cRNAs into oocytes decreased transport activity to 53.9% and 62.5% of control (L-cystine transport activity in oocytes injected with wild-type rBAT cRNA), respectively. Co-injection of E268K and T341A into oocytes strongly decreased amino acid transport activity to 28% of control. On the other hand, co-injection of wild-type and mutant rBAT did not decrease transport activity. Furthermore, immunological studies have demonstrated that the reduction of amino acid transport is not due to a decrease in the amount of rBAT protein expressed in oocyte membranes. These results indicate that mutations in the rBAT gene are crucial disease-causing lesions in cystinuria. In addition, co-injection experiments suggest that rBAT may function as a transport activator or regulatory subunit by homo- or hetero-multimer complex formation.

Improvement of coronary vasomotion with eicosapentaenoic acid does not inhibit acetylcholine-induced coronary vasospasm in patients with variant angina

Impaired function of the endothelium may be a mechanism of the coronary vasospasm induced by acetylcholine. We examined whether purified eicosapentaenoic acid (EPA), a major component of fish oil, improves the coronary vasomotion in response to acetylcholine, and the effect of purified EPA on acetylcholine (ACh)-induced coronary vasospasm in 22 patients with variant angina. ACh was infused into the coronary artery both before and after 4 months of EPA treatment (EPA 1.8 g/day, n = 12). In the control group (n = 10) that did not receive EPA, the response of the coronary diameter to ACh did not change over time. In the EPA-treated group, the cholinergic response in non-spastic sites changed from vasoconstriction to vasodilation, while ACh-induced coronary vasospasm persisted at the spastic sites. Therefore, EPA treatment improved the coronary vasomotor responsiveness to ACh, but did not inhibit ACh-induced coronary vasospasm.