Purification and characterization of the G203T mutant alpha i-2 subunit of GTP-binding protein expressed in baculovirus-infected Sf9 cells

We expressed the Gly203-->Thr (G203T) mutant of Gi2alpha, which was expected to show a dominant-negative phenotype in Gi2-mediated signal transduction, in baculovirus-inefected Sf9 cells and purified the mutant alpha subunit for its characterization. The rate of dissociation of GDP from G203T Gi2alpha was 3- to 4-fold faster than that from wild type Gi2alpha, but their kappacat values for GTP hydrolysis were almost the same. The affinities of the two Gi2alpha proteins for the beta gamma subunits of G proteins to form alpha beta gamma timers, which served as substrates for pertussis toxin-catalyzed ADP-ribosylation, were the same. In marked contrast, G203T Gi2alpha was unable to form a tight complex with a non- hydrolyzable analog (GTP[gammaS) of GTP; bound GTP[gammaS] was readily released from the mutant Gi2alpha even in the presence of a high concentration of Mg2+. Its susceptibility to tryptic digestion also revealed that GTP[gammaS]-bound G203T Gi2alpha formed a conformation apparently different from that of the GTP[gammaS]-bound form of wild-type Gi2alpha. Both the G203T and wild-type Gi2alpha proteins were capable of coupling with membrane-bound alpha2-adrenergic receptors, resulting in the formation of receptor-G protein complexes with high affinity for agonists. However, GTP[gammaS]-dependent uncoupling from high-affinity receptors was markedly attenuated in the case of G203T Gi2alpha. Thus, G203T-mutated Gi2alpha had a unique property in terms of coupling to membrane receptors, in addition to the previously expected defect in the active conformation of the GTP-bound form of Gi2alpha.

[Fontan procedure after pulmonary artery banding--surgical results and new anatomical repair for tricuspid atresia]

We examined our surgical experiences to determine the appropriate condition of pulmonary artery banding (PAB) for the Fontan procedure. From 1974 through 1992, thirteen patients underwent Fontan procedure following PAB at Tokyo Women's Medical College. Of these 6 had tricuspid atresia (TA), 5 had single ventricle, or 2 had other complex malformations. PAB was performed at the age of 1 to 14 months (mean 2.5 months). With monitoring pulmonary artery (PA) pressure and systemic arterial oxygen tension (PaO2), PA mean pressure decreased 43.6 to 18.8 mmHg and PA circumferences at the banding site decreased from 53.5 to 26.0 mm after PAB. This degree of PAB was tighter compared with the value estimated by Trusler's formula (27.9 mm) in most patients. After PAB, 5 patients required 8 additional palliative surgery including 3 systemic to pulmonary shunt, 3 rebanding, 1 palliative RVOTR to promote development of pulmonary vascular bed and 1 atrial septectomy to prevent pulmonary hypertension. Hemodynamic data before Fontan operation showed a tendency of higher PA pressure (17.5 vs 31.5 mmHg), and pulmonary vascular resistance (2.4 vs 5.5 Wood Unit) in non-survivors than in survivors. For patients with tricuspid atresia and high pulmonary vascular resistance, a new operation "Anatomical Repair" utilizing hypoplastic right ventricle with the translocation of pulmonary or aortic valve in tricuspid position was developed and successfully applied in three patients. In conclusion, initial tight PAB during early infancy and often repeated palliative surgery for development of adequate pulmonary vascular bed is the most important for maximizing the chance of subsequent successful Fontan procedure.

[A successful circulatory assist in acute left heart failure after a rapid two-stage arterial switch operation]

A 6-month-old female with transposition of the great arteries with intact ventricular septum successfully survived with the aid of a circulatory assist device for acute left heart failure after rapid two stage-arterial switch operation (ASO). The interval between pulmonary artery banding and ASO was 9 days. Left heart failure appeared immediately after ASO, so we started the circulatory assist with a centrifugal pump. The left ventricular function gradually recovered. After 43 hours assisted circulation, she was successfully weaned from the pump. Subsequent recovery was uneventful and the patient was discharged from the hospital on the 40th postoperative day. In case of acute left heart failure after ASO due to sudden changes in the left ventricular afterload, adaptation of the left ventricle can be expected by a relatively short period of circulatory assist with centrifugal pump.

Analysis of the sequence of a new cryptic plasmid, pRJF2, from a rumen bacterium of the genus Butyrivibrio: comparison with other Butyrivibrio plasmids and application in the development of cloning vector

A small cryptic plasmid, pRJF2, from Butyrivibrio fibrisolvens strain OB157 was isolated and sequenced. The plasmid is similar in organisation to the previously sequenced Butyrivibrio plasmid, pRJF1, with two open reading frames, ORF1 and ORF2, flanking a region tentatively identified as the replication origin, and a region of unknown function defined by terminal 79 bp invert repeats. The sequences of ORF1, ORF2, and the presumptive replication origin are highly conserved. The sequence between the 79, bp invert repeats is not, and is therefore presumed to be of lesser functional significance, although the 5' and 3' termini are still highly conserved. The functional importance for plasmid replication of these regions was tested by constructing potential shuttle vectors, each lacking one or more of the regions of interest. When the region between the invert repeats was deleted and replaced by the erythromycin resistance gene from pAM beta 1 together with pUC18, to produce the 7.9 kb chimaeric plasmid pYK4, the construct was successfully transformed into E. coli and B. fibrisolvens by electroporation, and was stably maintained in both hosts. Both ORF1 and ORF2 were required for successful transformation of B. fibrisolvens.

The equine pericardial valved conduit and current strategies for pulmonary reconstruction

In the period from 1976 to February 1995, 268 cases underwent extracardiac conduit repair (ECR), or direct reconstruction of the pulmonary artery. Of these 268 patients, 64 had a valved Dacron conduit, 143 received handmade valved equine pericardial conduits (Xenomedica), 24 had autologous fresh pericardial conduits, and 37 cases had pulmonary artery reconstruction by direct anastomosis without the use of tubular conduits. Hospital mortality in each group showed gradual improvement chronologically; 20.3% in the Dacron group, 9.8% in the equine conduit group, 4.2% in the autologous pericardial conduit group, and 5.4% in the direct anastomosis group, and the mortality rate was significantly higher in the Dacron group (P = .0261). Late death was seen in 7 of 51 (13.7%) in the Dacron group, 12 of 129 (9.3%) in the equine group, 1 of 23 (4.3%) in the autologous pericardial conduit, and none in the direct anastomosis group (P = .1263). Actuarial survival rates of the patients in the Dacron and equine conduit groups showed better survival in the latter without statistical significance: 75.0%, 83.2% at 5 years, and 69.7%, 80% at 10 years, respectively. However, actuarial survival rates among short-term survivors in the Dacron and equine conduit groups remained the same: 87.5%, and 88.7% at 10 years. Our current strategy in this entity is autologous tissue reconstruction of the pulmonary artery either by direct anastomosis or autologous pericardial conduit. Of 30 cases with transposed great arteries or truncus arteriosus, direct anastomosis could be performed in 19 (63.3%) since January 1992.(ABSTRACT TRUNCATED AT 250 WORDS)

Postoperative alteration in the size of Dacron vascular prostheses implanted in the infrarenal abdominal aorta

The degree and significance of postoperative alteration in the size of Dacron grafts in the infrarenal abdominal aorta was assessed by computed tomography. We studied a total of 41 knitted Dacron fabric grafts, comprising 28 Gelseal triaxial grafts and 13 Hemashield Microvel grafts, and 29 woven Dacron fabric (Veri-Soft Woven) grafts which were used to replace the infrarenal abdominal aneurysms. These three types of Dacron fabric dilated immediately after replacement to 1.4-1.5 times the manufactured size, but did not dilate further after the surgery.

In vitro evaluation of a pulsatile assist device for a centrifugal pump using a new principle

To induce a pulsatile flow in a centrifugal pump, we developed a new device (pulsatile assist device for centrifugal pump: PADCP) using a new concept. This device consists of a flexible polyurethane tube with an air chamber which is connected to the arterial side of the centrifugal pump circuit directly. A mock circulation system was used for evaluation of this PADCP. Thirty to 40 mm Hg of pulse pressure was obtained under 3-6 L/min of flow rate. By increasing the driving pressure of the PADCP from 200 to 600 mm Hg in a mock system, 4-48 mm Hg of pulse pressure was gained accompanied by a decrease in pump flow and increased left atrial pressure. The decreased pump flow and increased left atrial pressure were recovered easily by increasing the flow rate of the centrifugal pump. Pressures at the proximal site of the PADCP were less than 500 mm Hg. The PADCP was useful to induce a pulsatile flow in a centrifugal pump.

[Bypass grafting of left subclavian artery to descending thoracic aorta for relative stenosis of bypass graft after total correction for type A IAA with VSD]

A 4-year-old child underwent one-stage total correction for type A IAA with VSD in 1975 as the first successful case in Japan. At age 21, a gradual rise in her upper limb pressure to 190 mmHg prompted repeat catheterization, which showed a pressure gradient across the EPTFE graft of 58 mmHg. Under general anesthesia in the right lateral position, the patient's left thorax was reopened. The EPTFE graft had undergone patchy calcific degeneration and was significantly hardened. An 18-mm Toray graft preclotted with fibrin glue was anastomosed to the left subclavian artery in side-to-end fashion. Its distal end was anastomosed to the descending aorta distal to the EPTFE bypass during a 20-minute aortic occlusion. The postoperative recovery was uneventful and the pressure gradient between the upper and lower limbs fell to 0 at discharge. We chose this method for reoperation of type A IAA and CoA because of the reduced need for dissection and better effectiveness.

Surgical management of tricuspid malinsertion in the Rastelli operation: conal flap method

From June 1986 to May 1994, 25 patients underwent the Rastelli operation for complete transposition of the great arteries with ventricular septal defect and pulmonary stenosis or atresia. Fourteen patients whose tricuspid valve chordae were normal underwent the conventional Rastelli procedure (conventional group), whereas 11 patients who had tricuspid malinsertion into the infundibular septum underwent the Rastelli operation concomitant with mobilization of the infundibular septal flap, with the tricuspid valve chordae, to the right ventricular side of the intraventricular conduit (conal flap method) (conal flap group). In relation to the mobilization of the tricuspid valve chordae, right heart function and tricuspid regurgitation were compared between the two groups. There was one early death after the conventional Rastelli procedure and no early death after the Rastelli operation with a conal flap. There was one late death in the conventional group and two late deaths in the conal flap group. The mean follow-up was 50.8 +/- 5.1 months in the conventional group and 54.9 +/- 7.5 months in the conal flap group (p = 0.43). Reoperation was necessary for 1 patient in the conal flap group during follow-up. At the most recent follow-up, all patients in both groups were in New York Heart Association functional class I. Tricuspid regurgitation was estimated from the echocardiograms. Mild to moderate regurgitation was noted in 6 patients in the conventional group and 8 in the conal flap group. However, postoperative right heart catheterization data did not show any significant differences.(ABSTRACT TRUNCATED AT 250 WORDS)

[Reconstruction of pulmonary trunk in pulmonary atresia and tetralogy of Fallot utilizing autologous tissue]

Establishment of right ventricular-pulmonary arterial continuity with autologous tissue, avoiding the use of prosthetic conduit, is presented. From February 1992 through March 1993, 22 patients with pulmonary atresia and tetralogy of Fallot underwent reparative operation at The Heart institute of Japan. In 20 patients out of the 22 patients, the right ventricular-pulmonary arterial continuity was successfully established with either direct anastomosis or insertion of tailored autologous pericardial tube. The morphology of the right ventricular-pulmonary arterial discontinuity comprised of valvular and infundibular atresia in seven, truncal atresia in nine, and failed extracardiac conduit in four. In patients with relatively short distance between right ventricle and pulmonary artery, the pulmonary artery was retracted and anastomosed directly to the cranial margin of the ventriculotomy incision to serve as a smooth floor made of autologous tissue. In patients with long distance, tailored autologous pericardial tube was interposed between right ventricle and pulmonary artery instead of using prosthetic conduit. Both techniques were completed by mono- or bicuspid anterior patch made of equine pericardial conduit. There were no early and late deaths. Postoperative catheterization data showed satisfactory reduction of right ventricular pressure with the right-to-left ventricular systolic pressure ratio ranging from 0.42 to 0.69 (average 0.52) in direct anastomosis group and 0.43 to 0.48 (average 0.45) in autologous pericardial tube group, and the pressure gradient across right ventricular outflow tract ranged from 1 to 15 (average 8) mmHg and 1 to 15 (average 5.8), respectively. The distributing frequency of late complication, mainly conduit obstruction, of prosthetic materials prompted us to use autologous tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Enumeration of transconjugated Ruminococcus albus and its survival in the goat rumen microcosm

A transconjugant Ruminococcus albus A3 culture was released into a goat rumen, and the extent of its survival in the rumen microcosm was measured by distinguishing this bacterium from indigenous microbes by antibiotic resistance. A3 cells remained roughly constant for 14 days in this goat rumen.

[A case of adult Wilms' tumor with vena caval involvement]

The patient was a 35-year-old female with the chief complaint of macrohematuria. Computerized tomographic (CT) scan, ultrasonography and magnetic resonance imaging (MRI) revealed the presence of a large and inhomogeneous mass in the left kidney, and a tumor thrombus growing in the inferior vena cava. Angiography also showed a hypervascular tumor in the left kidney. The chest X-ray and CT scan demonstrated multiple metastatic lesions in the bilateral lungs. Radical nephrectomy and thrombectomy was performed under the diagnosis of left renal tumor with its invasion of inferior vena cava. Pathological findings revealed that this tumor was nephroblastoma, and its type was clear cell sarcoma of the kidney (CCSK). The patient received chemotherapy according to National Wilms' Tumor Study (NWTS) IV chemotherapeutic drug regimen. In general, CCSK is known to have poor prognosis. However, doxorubicin has been reported to have a relatively good antitumor effect for CCSK. However, in this case, the evaluation after the first course of chemotherapy was progressive disease, because some new lesions appeared, although most old pulmonary metastatic lesions were reduced.

[Serum concentration of vitamin K in elderly women with involutional osteoporosis]

Oral administration of vitamin K was reported to increase bone mineral density. However, the possible role of vitamin K in the pathogenesis of osteoporosis still remains unclear. Therefore, we measured the serum concentration of vitamin K1 and K2 (menaquinone-4, 7, 8) in 24 elderly women with osteoporotic vertebral compression fracture and in 36 elderly women without fracture. Major forms of vitamin K present in sera in this study were vitamin K1 and menaquinone-7. On the other hand, serum menaquinone-4 and -8 were undetectable in most women. Serum concentration of menaquinone-7 was significantly lower in women with fracture than in those without fracture (3.29 +/- 3.63 ng/ml vs 6.26 +/- 5.62, mean +/- SD, respectively), while no difference was found in serum vitamin K1 concentration (0.837 +/- 0.620 ng/ml vs 0.820 +/- 0.686, respectively). There was no difference between both groups in background data such as age, body height, body weight, and body mass index, as well as serum level of calcium, inorganic phosphate, creatinine, albumin, and alkaline phosphatase. These results suggest the possibility that deficiency of vitamin K, particularly that of menaquinone-7, is one of the risk factors for developing osteoporosis.

Autologous reconstruction of pulmonary trunk at reoperation after extracardiac conduit repair

Between 1991 and 1993, 5 patients underwent reoperation for critical stenosis of extracardiac conduit. Indication for extracardiac conduit repair was pulmonary truncal atresia in 3 patients and coronary anomaly including single left coronary artery and left anterior descending artery from right coronary artery in 2 patients. Age at reoperation ranged from 8 to 23 years (mean, 16.2 years). Preoperative systolic pressure ratio of right to left ventricles ranged from 0.83 to 1.05 (mean, 0.93), with the pressure gradient across the conduit ranging from 52 to 100 mm Hg (mean, 74.4 mm Hg). At reoperation, stenotic conduit was completely removed and central pulmonary artery was extensively mobilized. In 4 patients who had a relatively short distance (15 to 25 mm) between the pulmonary arterial stump and the right ventriculotomy incision, the distal pulmonary arterial stump was anastomosed directly to the cranial margin of the right ventriculotomy incision to serve as a floor mode of autologous tissue. In 1 patient with a long distance (40 mm), right ventricular-pulmonary arterial continuity was restored with a tailored autologous pericardial tube. There were no early or late deaths. Postoperative catheterization study revealed a satisfactory reduction of right ventricular pressure with the systolic pressure ratio ranging from 0.42 to 0.51 (mean, 0.47) and the pressure gradient across the right ventricular outflow tract ranged within 13 mm Hg (mean, 5 mm Hg). Restoration of right ventricular-pulmonary arterial continuity was successfully achieved by introducing the concept of autologous tissue repair even at reoperation instead of the insertion of new extracardiac conduit in patients with tetralogy of Fallot after extracardiac conduit repair.

[Surgical treatment of transposition of the great arteries with intact ventricular septum associated with left ventricular outflow obstruction]

Thirteen patients have undergone surgical treatment for transposition of the great arteries (TGA) with intact ventricular septum (IVS) associated with left ventricular outflow obstruction (LVOTO) in our institute. Ages at operation ranged from three months to six years (mean 9.2 +/- 4.7 months). Of these patients, seven had dynamic type LVOTO (group I), and six had organic LVOTO (group II). Preoperative left ventricular end-diastolic volume was significantly smaller in group II (78 +/- 13% of normal) than control group (135 +/- 53% of normal). Preoperative pressure gradient between the pulmonary artery and left ventricle was significantly greater in group II (55.8 +/- 3.2 mmHg) than group I (35.2 +/- 3.9 mmHg). In group I, II patients underwent two-stage ASO, the other 5 patients underwent Senning operation. The reason for the Senning operation were era before introduction of ASO in our institute (1983) or unsuccessful training of the left ventricle. In group II, all but one patient underwent Senning operation, the other underwent a successful Fontan operation with Damus anastomosis because of too small left ventricle (LVEDV: 49% of normal). Techniques to correct LVOTO at the definitive operation included ventriculotomy (n = 4) and pulmonary valvotomy (n = 2). One patients in group II underwent a Fontan operation with Damus anastomosis due to an underdeveloped left ventricle (LVEDV: 49% of normal). There was no early or late death. The postoperative pressure gradients disappeared or reduced to trivial levels in all patients. At present no LVOTO has developed in any of the patients.

[Two cases of successful arterial switch operation for double outlet right ventricle associated with straddling and cleft mitral valve]

We successfully performed an anatomical repair for double outlet right ventricle associated with straddling and cleft mitral valve in two patients. In both patients position of the anterior and posterior papillary muscles was found to be normal. Therefore, all staddled mitral component was detached. The mitral valve competency was achieved by suture-closure of the cleft and annuloplasty. This procedure facilitated intraventricular re-routing from the left ventricle to the pulmonary artery. Then arterial switch was performed. Postoperative course was uneventful and no significant mitral valve regurgitation was found in either patient postoperatively. This procedure can be a good option in patients with double outlet right ventricle associated with straddling mitral valve.

[The findings indicate that HSP70 expression is closely related to ischemic brain injury, and that HSP70 expression is not related to either breakdown of the blood-brain barrier or reactive axonal changes]

The relationship between the 70-kilodalton hear shock protein (HSP70), morphological changes in neurons, protein extravasation, and reactive axonal changes was evaluated in rats with fluid percussion injuries to the right side of the brain. (4.8-5.6 atm, 20 ms). From 1 hour to 2 weeks after injury (or sham injury), serial sections of the brains were immunostained with antibodies to HSP70, rat IgG, and 68-kilodalton neurofilament. Ischemic changes in neurons in the injured cortex were noted in samples taken from 6 to 48 hours after injury, and macroscopic hemorrhages were noted in the corpus callosum and external capsule. Reactive axonal swelling was observed in the brain stem in samples taken from 6 to 48 hours after injury. Immunostaining of HSP70 was positive in the injured cortex from 6 hours to 1 week after injury. Maximal immunostaining was observed by 48 hours after injury in the injured cortical layers II and III. The region of HSP70 expression at 24 and 48 hours postinjury was the same as the region of ischemic cell changes. There were discrepancies between the region of HSP70 expression and the regions of IgG immunoreactivity and reactive axonal changes. These findings indicate that HSP70 expression is closely related to ischemic brain injury, and that HSP70 expression is not related to either breakdown of the blood-brain barrier or reactive axonal changes.

Monitoring for engraftment following rat orthotopic liver transplantation by in vitro amplification of Y-chromosome gene using polymerase chain reaction

The polymerase chain reaction (PCR) using primers specific for the rat Y-chromosome gene made it possible to distinguish a very small number of male rat cells from a large excess of female rat cells. In nonimmunosuppressed LEW recipients of ACI liver allografts, the donor cells in the bloodstream disappeared rapidly by day 3, earlier than the biochemical changes indicative of liver dysfunction. In immunosuppressed LEW recipients of ACI liver allografts, the donor cells were detected for a longer time. Moreover, in LEW recipients surviving for long period, the PCR revealed mixed-microchimerism. Our results indicated that this Y chromosomal gene-specific PCR method is useful for assessing engraftment following rat liver transplantation.

Enzyme properties of Aplysia ADP-ribosyl cyclase: comparison with NAD glycohydrolase of CD38 antigen

An ecto-enzyme of NAD glycohydrolase (NADase) induced by retinoic acid in HL-60 cells is attributed to the molecule of CD38 antigen [Kontani, K., Nishina, H., Ohoka, Y., Takahashi, K., and Katada, T. (1993) J. Biol. Chem. 268, 16895-16898]. CD38 antigen has an amino acid sequence homologous to Aplysia ADP-ribosyl cyclase which generates cyclic adenosine diphosphoribose (cADPR) and nicotinamide (NA) from beta-NAD+. On the basis of this sequence homology, we compared enzyme properties between CD38 NADase expressed as a fusion protein in Escherichia coli and ADP-ribosyl cyclase purified from the ovotestis of Aplysia kurodai. 1) beta-NAD+ analogs, nicotinamide 1, N6-ethenoadenine dinucleotide, and nicotinamide hypoxanthine dinucleotide, did not serve as good substrates for the ADP-ribosyl cyclase, suggesting that the intact adenine ring of beta-NAD+ was required for the cyclase-catalyzed reaction. On the other hand, CD38 NADase utilized the NAD analogs to form ADP-ribose and NA. 2) Kinetic analyses of the ADP-ribosyl cyclase reaction revealed that NA was first released from the substrate (beta-NAD+)-enzyme complex, followed by the release of another product, cADPR, which was capable of interacting with the free enzyme. 3) The enzyme reaction catalyzed by the ADP-ribosyl cyclase was fully reversible; beta-NAD+ could be formed from cADPR and NA with a velocity similar to that observed in the degradation of beta-NAD+. However, CD38 NADase did not catalyze the reverse reaction to form beta-NAD+ from ADP-ribopase and NA. 4) The CD38 NADase activity was, but the ADP-ribosyl cyclase activity was not, inhibited by dithiothreitol.(ABSTRACT TRUNCATED AT 250 WORDS)

Significance of the HLA-DQB matching in one-haplotype identical kidney transplant pairs and the matching analysis by the polymerase chain reaction (PCR)--heteroduplex--polymorphism method

Sixty-five living related kidney transplant pairs were analyzed for matching at HLA class II loci by the polymerase chain reaction (PCR)--sequence specific oligonucleotide probe (SSOP) method. The retrospective HLA matching study revealed that there were many early graft loss cases despite the DQB compatibility, contrary to our expectation. There were 54 DRB1 one-mismatched cases, in which 7 of the 11 (64%) DQB zero-mismatched cases had lost their grafts, while the graft loss cases were only 10 of the 43 (23%) DQB one-mismatched pairs (P value = 0.0006). The DQB matching of these cases was studied in detail, because the PCR-SSOP methods are based on the detection of sequence polymorphisms in a relatively narrow range, i.e., recognized sequences by SSOPs. The PCR--heteroduplex--polymorphism analysis method was developed to analyze the polymorphism in exon 2 of the DQB1 gene. However, all the pairs proved to be compatible for the DQB, demonstrating that the DQB compatibility was associated with a harmful influence on the graft outcome. These observations suggested that the DQB1 incompatibility might exert the low responsiveness to HLA haplo-identical allogeneic transplants.

Characterization of an acidic polysaccharide with immunological activities from the tuber of Pinellia ternata

An acidic polysaccharide, called pinellian PA, was isolated from the tuber of Pinellia ternata Breit. It was homogeneous on electrophoresis and gel chromatography, and its molecular mass was estimated to be 11.8 x 10(4). Pinellian PA is composed of L-arabinose: D-galactose: L-rhamnose: D-galacturonic acid: D-glucuronic acid in the molar ratio of 5:15:1:3:3, in addition to small amounts of O-acetyl groups and peptide moieties. Reduction of carboxyl groups, methylation analysis and nuclear magnetic resonance studies show that the core structural features include a backbone chain composed of beta-1,3-linked D-galactose units. Some of the galactose units in the backbone carry beta-1,6-linked D-galactosyl side-chains at position 6. Pinellian PA produces significant potentiation of the reticuloendothelial system, as shown by a carbon clearance test, and also exhibits potent anti-complementary activity.

Molecular cloning of cDNA encoding human DNA helicase Q1 which has homology to Escherichia coli Rec Q helicase and localization of the gene at chromosome 12p12

A complementary DNA encoding DNA-dependent ATPase Q1 possessing DNA helicase activity, which is the major DNA-dependent ATPase in human cell extracts, was cloned from a cDNA library of human KB cells. The predicted amino acid sequence has seven consecutive motifs conserved in the RNA and DNA helicase super family and DNA helicase Q1 belongs to DEXH helicase family. A homology search indicated that helicase Q1 had 47% homology in the seven conserved regions with Escherichia coli RecQ protein. Three RNA bands of 4.0, 3.3, and 2.2 kilobases were detected in HeLa cells by Northern blotting. Analysis of the genomic DNA indicated the presence of a homologous gene in mouse cells. The DNA helicase Q1 gene was localized on the short arm of human chromosome 12 at 12p12.