Binding of Actinomyces viscosus to collagen: association with the type 1 fimbrial adhesin

Treatment of hydroxyapatite (HA) with human type I or type III collagen strongly promoted adhesion of Actinomyces viscosus LY7 cells. Treatment with human type V collagen was somewhat less effective while treatment with human type IV or rat type I collagen was significantly less effective. Electron microscopic observations revealed that A. viscosus cells also attached to fibrils prepared from human type I collagen. The alpha 1 (1) polypeptide chain derived from type I collagen was ineffective in promoting binding and the alpha 2 (1) polypeptide chain exhibited moderate activity. Heat- or urea-denatured type I collagens were also ineffective in promoting binding. Mutants of A. viscosus that possess type 1 fimbriae, but not type 2 fimbriae or no fimbriae, also bound to collagen-treated HA; this suggests that the adhesin responsible was associated with type 1 fimbriae. Strains of Actinomyces israelii and Actinomyces odontolyticus also exhibited strong binding to collagen-treated HA, while Actinomyces naeslundii ATCC 12104 did not. The avidity of Actinomyces species for collagen would seem to be at least partially responsible for the high proportions of these organisms found on cemental and root tooth surfaces.

[Amino acid analysis of the main organs during different growing periods of panax ginseng C.A. Mey]

Studies on different growing periods of Panax ginseng, its ages and the variation regularities of amino acids in its main organs are reported. The test has shown that it contains seventeen amino acids. The total amount of amino acids reaches its peak point during the sprouting period (in April), next to it is the withering period (in September), flowering and fruiting periods being the lowest (in June). The amount of these acids in the main root is higher than that in the fibrous root, the lowest being in the lateral root. Five-year-old Panax ginseng features the highest amount.

Improved preservation of the rat liver for orthotopic liver transplantation: use of University of Wisconsin-lactobionate solution and retrograde reflushing

This study investigated cold preservation and reflushing before orthotopic liver transplantation by examining (1) new University of Wisconsin solution (UW) versus Euro-Collins solution (EC), (2) retrograde reflushing (RR) versus antegrade reflushing (AR), and (3) the addition of a platelet-activating inhibitor (PAF), superoxide disumatase (SOD), or SOD + catalase to UW. Syngeneic, male Lewis rats (200 to 400 gm) were used. Preservation for 9, 12, 18, or 24 hours in UW or EC with RR (through the inferior vena cava) was used. The 9- and 12-hour groups experienced a significant decrease in the weight of the grafts preserved in UW. The 3-week survival rate after 9 hours of preservation (n = 6) in UW was 66%, and the survival rate with EC was 0% (p less than 0.025). After 12 hours of preservation, recipient survival rate was 70% (n = 10) with UW versus 0% (n = 4) with EC (p less than 0.025). RR of the graft with cold lactated Ringer's solution immediately before reimplantation significantly improved 3-week survival in the 12-hour group to the level of the control group (no preservation time, 69%). Preservation for 12 hours in UW followed by AR yielded a 3-week survival of 14%; 3-week survival for the RR group was 70% (p less than 0.025). Furthermore, RR allowed a 3-week survival of 33% and 20% after 18 and 24 hours of UW preservation, respectively. In the 24-hour RR/UW group, donor pretreatment with SRI 63-441 (20 mg/kg, intravenously) and recipient treatment with SOD (15 mg/kg, intravenously) or SOD + catalase (15 mg/kg and 5000 units/kg, intravenously) produced a 3-week survival comparable to preservation in UW followed by RR alone. These studies show that UW is a profound improvement over EC for cold preservation of liver and that the new application of RR to rat orthotopic liver transplantation improves survival. However, the addition of free-radical scavengers or PAF does not improve organ function or recipient survival in this model.

[Diagnosis of fetal urinary tract deformity and its early surgical treatment]

From July 1987 to August 1989, ultrasound scan was performed in 419 cases of 24-42-week gestation. The result of antepartum diagnosis showed 12 cases of anomaly (7 males and 5 females). After birth, they were all confirmed by pediatric surgery. Seven infants had hydronephrosis (either bilateral or unilateral), two had nephrocystosis (either unilateral or multiple), two had megaureter, one had megabladder, one had single kidney associated with chronic disease, and eight were operated on. The lowest operative age was nine days, and the average age was 72 days. It shows that The operative indications were: (1) increased excretory rate of RBC and WBC; (2) functional damage of tube of kidney; (3) decreased serum albumin and metabolic acidosis; (4) bacteriuria and pyouria; (5) absence of general complications (6) pyelocalicectasis was at least three times that of the healthy side; (7) obstruction of the low urinary tract and or bladder-rectum fistula. Early surgical management is important for eugenic development of the infants.

Are cystgastrostomy and cystjejunostomy equivalent operations for pancreatic pseudocysts?

To compare the effectiveness of cystgastrostomy and cystjejunostomy for treatment of pancreatic pseudocysts, 39 patients with cystgastrostomy were compared to 59 patients with cystjejunostomy. The groups were comparable in age, sex, cause of pancreatitis, pseudocyst location, symptoms, and preoperative serum amylase level. Cysts treated with cystgastrostomy were larger (mean diameter, 11.1 +/- 0.9 cm) than cysts treated by cystjejunostomy (mean diameter, 6.7 +/- 0.7 cm) (p less than 0.05). Mean duration of surgery was 148 +/- 11 minutes for cystgastrostomy versus 265 +/- 15 minutes for cystjejunostomy (p less than 0.05). Mean blood loss was 397 +/- 82 ml for cystgastrostomy versus 703 +/- 80 ml for cystjejunostomy (p less than 0.05) Mean intraoperative fluid requirements were 2640 +/- 313 ml for cystgastrostomy and 4403 +/- 362 ml for cystjejunostomy (p less than 0.05). Cyst recurrence was 10% for cystgastrostomy versus 7% for cystgastrostomy. Postoperative gastrointestinal bleeding occurred in 8% of patients with cystgastrostomy and in 2% of patients with cystjejunostomy. Infection problems with cystjejunostomy included two wound infections and one case of septicemia; infection problems with cystjejunostomy included five intraabdominal abscesses, two wound infections, and one case of pneumonia. Two patients died with cystgastrostomy (both from gastrointestinal bleeding); two patients died with cystjejunostomy (one from intraabdominal sepsis and one from pulmonary embolus). Cystgastrostomy was used for significantly larger pseudocysts and was associated with significantly less blood loss and operating time than cystjejunostomy (p less than 0.05). Morbidity and mortality from cystgastrostomy and cystjejunostomy were comparable, although gastrointestinal bleeding was more common with cystgastrostomy and intraabdominal abscess was more common with cystjejunostomy. Since cystgastrostomy can usually be performed more quickly and with less blood loss, it should be considered whenever anatomically feasible.

Inhibition of free radical generation and improved survival by protection of the hepatic microvascular endothelium by targeted erythrocytes in orthotopic rat liver transplantation

The capacity of specifically targeted erythrocytes to inhibit free radical-mediated injury to the endothelial cell after cold preservation, and improve liver function was studied in two experimental models: An isolated perfused rat liver (IPRL) system and syngeneic orthotopic rat liver transplantation. In the IPRL model, livers were preserved in University of Wisconsin solution for 24 h at 4 degrees C. At the end of the preservation period, livers were flushed with lactated Ringer's (control), immunoerythrocytes (IES), or blank intact erythrocytes prior to warm reperfusion for 2 h using an assanguinous Krebs-Henseleit buffer. Production of superoxide (O2-) anion during warm reperfusion in the IES-treated liver was reduced by 65% as compared with controls (P less than 0.001) and by 74% (P less than 0.001) when compared with blank erythrocyte-treated livers. Endothelial cell preservation, as assessed by levels of purine nucleoside phosphorylase (PNP), was much better in the IES-treated group (P less than 0.001) when compared with untreated livers. Hepatocellular preservation was markedly improved in the IES-treated livers. In the syngeneic liver transplantation model, livers were preserved in UW solution for 24 h at 4 degrees C. Prior to implantation, livers were flushed with 5 ml of cold lactated Ringer's or immunoerythrocytes. Survival after three weeks was 60% in the IES-treated group and 30% in the untreated group. Survival in the IES-treated group was not significantly different from a control (no preservation) group. IES-treated livers in both models demonstrated better endothelial cell integrity and ultimate liver function. IES treatment therefore appears to protect the hepatic microvascular endothelial cell from reperfusion injury and could prove to be an easy reproducible method of donor organ preparation after cold preservation.

Binding of streptococci of the "mutans" group to type 1 collagen associated with apatitic surfaces

The present study surveyed the ability of 21 strains of cariogenic streptococci of the "mutans" group to bind to human type 1 collagen adsorbed on hydroxyapatite (HA) surfaces. All strains of Streptococcus cricetus (serotype a) and Streptococcus rattus (serotype b) tested attached strongly to collagen-treated HA (C-HA). Streptococcus mutans strains of serotype c and Streptococcus sobrinus strains of serotype d or g attached poorly; or not at all, to C-HA. S. mutans strains OMZ-175 (serotype f) and B14 (serotype e) were exceptions which exhibited significant binding to C-HA. Binding of S. cricetus AHT and S. rattus LB-1 to C-HA occurred in a dose-dependent manner, and was specific since it was inhibited by the presence of soluble collagen, but not by egg albumin, or by human fibrinogen or fibronectin. Binding occurred maximally between pH 6 and 8 and was not affected by any of several sugars tested. Trypsin treatment the streptococci had little affect, but heating at 100 degrees C reduced their ability to bind to C-HA.

Streptococcus cricetus and Streptococcus rattus bind to different segments of collagen molecules

Strains of Streptococcus cricetus and Streptococcus rattus exhibited striking differences in their ability to bind to different types of collagen. For example, S. cricetus AHT bound in highest numbers to hydroxyapatite (HA) treated with human type V collagen, while rat type I collagen was ineffective. In contrast, human type V collagen was least effective in promoting attachment of S. rattus LB-1, while treatment with rat or human type I collagen was effective. Adsorption of both species to human type I collagen-treated HA showed a high correlation with a Langmuir model. Estimates of adsorption parameters indicated there were greater numbers of binding sites with higher affinity for S. rattus LB-1 than for S. cricetus AHT. Treatment of HA with either the alpha 1 (1) or alpha 2 (1) polypeptide chains of collagen was effective in promoting adhesion of S. rattus LB-1 cells. In contrast, the alpha 2 (1) chain was more effective than the alpha 1 (1), chain for S. cricetus AHT. These observations indicate that S. cricetus AHT and S. rattus LB-1 cells bind to different segments of collagen molecules. Adhesion of both species was also promoted by collagen-rich fractions of human dentin.

[406 cases of angina pectoris in coronary heart disease treated with saponin of Tribulus terrestris]

Coronary heart disease (CHD) was treated with saponin of Tribulus terrestris. According to 406 cases of clinical observation and a cross test (67 cases treated with Yufen Ningxin Pian as control), the results showed that the total efficacious rate of remission angina pectoris was 82.3%. It was higher than the control group with a total effective rate of 67.2% (P less than 0.05). The total effective rate of ECG improvement (52.7%) was even higher than that of the control group (35.8%). It is shown that saponin of Tribulus terrestris has the action of dilating coronary artery and improving coronary circulation, and thus has better effects on improving ECG of myocardial ischemia. If taken for a long time, it has no adverse reaction on blood system and hepatic and renal functions. Neither does it have side effects. It is one of the ideal medicines to treat angina pectoris.

Vitamin C deficiency in patients with sickle cell anemia

Because peroxidative damage to red cell membranes may contribute to the pathophysiology of sickle cell disease, deficiency of fat- and water-soluble antioxidants could be a determinant in the pathogenesis of this disease. We have previously reported a deficiency of vitamin E in sickle cell disease. The present study was undertaken to see if a deficiency in vitamin C might also be detected. Leukocyte vitamin C, which reflects total body vitamin C reserve, was measured by a modified 2,4-dinitrophenylhydrazine method. Sickle cell patients (N = 18) had lower leukocyte vitamin C levels (18.3 +/- 9.4 micrograms/10(8) cells) than normal controls (N = 12; 30.3 +/- 7.5 micrograms/10(8) cells; p less than 0.01). Furthermore, 50% of the patients had vitamin C levels below 15 micrograms/10(8) cells, a value consistent with vitamin C deficiency. A statistically significant correlation (r = -0.62 with 0.01 less than p less than or equal to 0.025) was found between leukocyte vitamin C levels and serum ferritin concentration. Because dietary vitamin C intake appeared to be adequate, increased vitamin C utilization may account for this deficiency. However, the mechanisms for this deficiency as well as its pathophysiologic consequences remain to be established.

A modified apparatus for dual, sterilized, isolated perfusion of the rat liver

The isolated perfused rat liver (IPRL) has proven to be a useful model for the study of physiology and pathology of the liver. For research in nonparenchymal cell (NPC) function that includes measurement of cytokine production (eg, TNF), it is necessary to have a sterilized perfusion system. We have modified the IPRL apparatus so as to be able to perform sterile perfusions of two livers simultaneously. The perfusion apparatus is a recirculating closed system in which the oxygenator is a plastic container separated into two chambers by a fenestrated plastic wall. A disposable macropore filter functions as both a bubble trap and perfusate filter. The sterilization process is done by immersing the various components in Benz-All solution. The tubing is disinfected by irrigation with 10% Clorox followed by 0.9% sodium chloride solution. The perfusate used is filter-sterilized Krebs buffer solution containing 0.5 g Mandol/250 mL perfusate. Not only can two organs be conveniently perfused simultaneously, but the entire system can be reliably sterilized for up to 20 consecutive perfusions. Bile production is higher and more stable with less leakage of intracellular enzymes. Many of the components are disposable and can be altered to suit the needs of a particular experiment.

Prognostic value of lupus band test in unexposed normal skin of patients with systemic lupus erythematosus

Biopsy specimens of normal unexposed buttock skin were taken from 71 patients with systemic lupus erythematosus (SLE) for lupus band test (LBT). Correlation of positive incidence, fluorescent intensity, protein classes and numbers of LBT with SLE activity including active nephropathy were studied. Positive LBT results are associated with SLE disease activity, decreased CH50 and C3, ANA peripheral pattern and positive AdsDNA antibodies, but not with active nephropathy per se. Although LBT results of unexposed normal skin can reflect SLE activity, its prognostic value should not be overestimated.

[Study on "massage to activate the meridian" apparatus in the treatment of cholecystolithiasis]

This apparatus is designed in accordance with the doctrine and principles of traditional Chinese medicine and based on the theory of meridian and specific massage procedure in conjunction with the "Information Theory" and electron utilizing technique. It utilizes a programmed induction "Special Wave" to stimulate a series of acupuncture points, combined with administration of western drugs from a regime of "General Attack" treatment on the gallbladder stones, to enhance their evacuation. By stimulating the specific acupuncture points with this apparatus through the action of "Special Wave" strong contraction of the gallbladder can be elicitated. Experiments on dogs showed that under such stimulation the intra-gallbladder pressure can be increased 26 times, producing a jet of bile flow which facilitates the expulsion and evacuation of stones in the gallbladder. Method of use: first place a conductive rubber pad on the acupuncture point to be stimulated, then use a hand-held electrode to massage-stimulate the meridian. It is carried out forward and backward along the direction of meridian. The whole procedure is carried out under direct visualization with the help of ultrasonic B-scan. When dilatation of the common bile duct is observed, the hand-help electrode is used to perform push-compress massage on the meridian, and acupuncture points making the stones enter the common bile duct B-scan give proper orientation for the manipulation. This method has been tested clinically on 410 patients with good results. The evacuation rate of the gallbladder stones was 92.7% with complete evacuation achieved in 17.3%.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of recombinant soluble CD4 in rhesus monkeys infected with simian immunodeficiency virus of macaques

The CD4 molecule is a high-affinity cell-surface receptor for the human immunodeficiency virus (HIV-1) and a soluble truncated form of CD4 produced by recombinant DNA technology is a potent inhibitor of HIV-1 replication and HIV-1-induced cell fusion in vitro. Rhesus monkeys infected with the simian immunodeficiency virus of macaques (SIVMAC), a virus closely related to HIV-1, develop an AIDS-like syndrome, and so provide an important model for the evaluation of potential AIDS therapies. We have assessed the therapeutic effect of recombinant soluble CD4 in SIVMAC-infected rhesus monkeys. Virus was readily isolated from peripheral blood lymphocytes and bone marrow cells of these animals before starting treatment with soluble CD4, but became difficult to isolate soon after treatment had begun. Moreover the diminished growth of both granulocyte-macrophage and erythrocyte progenitor colonies from the bone marrow of these monkeys rose to normal levels during treatment. These findings indicate that soluble CD4 could prove valuable in the treatment of AIDS.

Effect of recombinant soluble CD4 on human peripheral blood lymphocyte responses in vitro

We have previously demonstrated that recombinant soluble CD4 protein (rsT4) blocks both HIV-1 infection of CD4 bearing lymphocytes and syncytium formation in vitro. (Recombinant soluble CD4 is designated by rsT4). Hence, we suggested the use of rsT4 in therapy for AIDS or the prevention of HIV-1 infection in individuals with a known risk of exposure. However, concerns arose that rsT4 might be immunosuppressive because of its implicated role in the enhancement of certain lymphocyte activation events through its engagement of MHC class II molecules on target cells. We therefore assessed the effect of recombinant soluble CD4 upon a number of functional and activation parameters of lymphocytes, including cellular proliferation, IL-2 secretion, and cytolytic capability, after antigenic or mitogenic stimulation. We report here that rsT4, at 60-fold over the concentration needed to block acute HIV-1 infection in vitro, does not significantly inhibit the activation of human peripheral blood lymphocytes by either PHA, tetanus toxoid or allogeneic cells. These results indicate that rsT4 will potentially exert minimal immunosuppressive effects in vivo, thus supporting the feasibility of clinical trials of rsT4 in the treatment or prevention of AIDS. In addition, the implications of these results for the interactions between CD4 and MHC class II molecules during lymphocyte activation are discussed.

HIV infection is blocked in vitro by recombinant soluble CD4

The T-cell surface glycoprotein, CD4 (T4), acts as the cellular receptor for human immunodeficiency virus, type 1 (HIV-1), the first member of the family of viruses that cause acquired immunodeficiency syndrome. HIV recognition of CD4 is probably mediated through the virus envelope glycoprotein (gp120) as shown by co-immunoprecipitation of CD4 and gp120 (ref.5) and by experiments using recombinant gp120 as a binding probe. Here we demonstrate that recombinant soluble CD4(rsT4) purified from the conditioned medium of a stably transfected Chinese hamster ovary cell line is a potent inhibitor of both virus replication and virus-induced cell fusion (syncytium formation). These results suggest that rsT4 is sufficient to bind HIV, and that it represents a potential anti-viral therapy for HIV infection.

Structural analysis of the locus containing the human C-reactive protein gene and its related pseudogene

The gene for human C-reactive protein (CRP) is mapped within a 34-kilobase pair genomic DNA segment identified by chromosome walking through overlapping DNA fragments cloned into a lambda phage library. Within 16 kilobase pairs upstream and downstream of the locus for the authentic CRP gene, only one other sequence homologous to that for CRP could be found. Sequencing analysis indicates this sequence to be a pseudogene with 50-80% region-specific homology. Comparison of the authentic CRP gene cloned from genomic DNA libraries independently prepared from three patients indicates no difference in the 5' and 3' flanking region, promoter region, or coding sequence. Only a polymorphism in the length of the poly(GT) stretch located in the intron is observed. There appears to be only one gene locus and copy per haploid chromosome for the authentic CRP gene and its pseudogene.

Purification and characterization of serotype 6 fimbriae from Bordetella pertussis and comparison of their properties with serotype 2 fimbriae

Fimbriae were removed from Bordetella pertussis (serotype 1.3.6) by mechanical shearing and purified by precipitation with ammonium sulfate, pH-dependent precipitation at pH 7.4, followed by two successive extractions of the precipitated fimbriae with 4 M urea. By electron microscopy, the precipitated fimbriae appeared as aggregated bundles of long, relatively straight filaments which were disaggregated to individual flexuous filaments at pH 10.5. These purified fimbriae were identified as serotype 6 agglutinogens, since antibody to the purified fimbriae agglutinated B. pertussis strains serotyped as 1.3.6, 1.2.3.6, or 1.2.3.4.6 but did not agglutinate strains of serotype 1.2.3.4, 1.2.3, or 1.3. In contrast, antibody to serotype 2 fimbriae only agglutinated B. pertussis strains containing serotype 2 agglutinogen. Purified type 6 and 2 fimbriae were found to be weakly cross-reactive by enzyme-linked immunosorbent assay, using polyclonal antibody to each type of fimbria. In an immunoblot assay, polyclonal antibodies to a 22,000-dalton subunit of fimbriae from B. bronchiseptica reacted strongly with the type 2 fimbrial subunit of B. pertussis, but only weakly with the type 6 subunit. When subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the protein subunit of the type 6 fimbriae migrated with a molecular weight of 21,500, whereas the type 2 fimbrial subunit had a molecular weight of 22,000. The two types of subunits had similar amino acid compositions and showed amino-terminal sequence homology in 15 of 21 amino acids. The amino-terminal amino acid sequences of the B. pertussis fimbriae were distinct from those reported for fimbriae from other gram-negative bacteria. Neither the type 6 nor the type 2 fimbriae caused hemagglutination when assayed with several types of erythrocytes.

[[Demographic aspects of urbanization in the Lower Yangtze region in China, circa 1500-1900]]

Urbanization trends in the Lower Yangtze region of China from 1500 to 1900 are examined. Data are from a variety of sources, including genealogies, local records, and other literature. An attempt is made to analyze the demographic characteristics of the urban population. "The demographic characteristics in respect to marriage, fertility and mortality found from the genealogies do reveal that there were dissimilarities between the rural and urban dwelling populations. Moreover, findings related to migration tend to support that rural to urban migration was an important factor that speeded up urbanization in the Lower Yangtze Region." (SUMMARY IN ENG)

Agricultural change and population growth: a brief survey on the case of China in historical perspective

A historical review of the relationship between agricultural change and population growth in China is presented. "This paper will try to discuss four aspects of agricultural change that are related to population growth. They are: (1) expansion of agricultural frontier, (2) changes in cultivation methods and land use, (3) improvements in agricultural technology, and (4) irrigation and water-control. Each of these aspects [is] treated briefly with temporal and spatial perspectives...." The relevance of the Boserup theory that population pressure leads to agricultural development is considered in the Chinese context. It is found that some evidence supports the theory. (summary in CHI)

More on the need for circadian, circaseptan and circannual optimization of cyclosporine therapy

Cyclosporine chronotherapy of pancreas-allotransplanted rats revealed, beyond a circadian stage-dependence of equal daily doses, further gain in graft function from doses varying from day to day with an about 7-day periodicity, the first highest dose being given on the 3rd or 5th day after surgery.

Pertussis toxin-catalyzed ADP-ribosylation of transducin. Cysteine 347 is the ADP-ribose acceptor site

Pertussis toxin catalyzes the transfer of ADP-ribose from NAD to the guanine nucleotide-binding regulatory proteins Gi, Go, and transducin. Based on a partial amino acid sequence for a tryptic peptide of ADP-ribosylated transducin, asparagine had been characterized as the site of pertussis toxin-catalyzed ADP-ribosylation. Subsequently, cDNA data for the alpha subunit of transducin indicated that the putative asparagine residue was, in fact, not present in the protein. To determine the amino acid that served as the ADP-ribose acceptor, radiolabel from [adenine-U-14C]NAD was incorporated, in the presence of pertussis toxin, into the alpha subunit of transducin (0.3 mol/mol). An ADP-ribosylated, tryptic peptide was purified and fully sequenced by automated Edman degradation. The amino acid sequence, Glu-Asn 343-Leu-Lys-Asp 346-X-Gly 348-Leu-Phe, corresponds to the cDNA sequence coding the carboxyl-terminal nonapeptide, Glu 342-Phe 350, which includes by cDNA sequence cysteine at position 347. Neither Asn 343 nor Asp 346 appeared to be modified; residue 347 adhered to the sequencing resin. Cysteine, the missing residue, was eluted from the sequencing resin with acetic acid along with 76% of the peptide-associated radioactivity, half of which, presumably ADP-ribosylcysteine, eluted from an anion exchange column between NAD and ADP-ribose; the other half had a retention time corresponding to 5'-AMP. We conclude that Cys 347 and not Asn 343 or Asp 346 is the site of pertusis toxin-catalyzed ADP-ribosylation in transducin.

Genomic DNA sequence for human C-reactive protein

The gene for the prototype acute phase reactant, C-reactive protein, has been isolated from two lambda phage libraries containing inserted human DNA fragments using synthetic oligonucleotide probes. Nucleotide sequence analysis indicates that after coding for a signal peptide of 18 amino acids and the first two amino acids of the mature protein, there is an intron of 278 base pairs followed by the nucleotide sequence for the remaining 204 amino acids. The intron is unusual in that it contains on the positive strand a poly(A) stretch 16 nucleotides long and a poly(GT) region 30 nucleotides long which could adopt the Z-form of DNA. The nucleotide sequence reported here confirms the amino acid sequence of mature C-reactive protein as originally reported except that it codes for an additional 19 amino acids beginning at position 62. Thus DNA sequence analysis predicts that the mature protein consists of 206 amino acids rather than 187 as originally reported. The mRNA cap site is located 104 nucleotides from the start of the signal peptide and there is a 3' noncoding region 1.2 kilobase pairs in length. The gene has a typical promoter containing the sequences TATAAAT and CAAT 29 and 81 base pairs upstream, respectively, of the cap site.

Purification and properties of a plasmid-encoded 2,4-dichlorophenol hydroxylase

2,4-Dichlorophenol hydroxylase, an enzyme involved in the bacterial degradation of the herbicide 2,4-dichlorophenoxyacetate (2,4-D) was purified from two bacterial strains that harbored the same 2,4-D plasmid, pJP4. The purified enzymes (Mr 224 000) from the two transconjugants were indistinguishable; they contained FAD and were composed of non-identical subunits, Mr 67 000 and 45 000, respectively. Various substituted phenols were hydroxylated, using either NADH or NADPH. The amino acid composition of the native enzyme was determined.

Frequency of lambda light chain subtypes in mouse antibodies to the 2,4-dinitrophenyl (DNP) group

Of the three lambda chain subtypes made by inbred mice, chains of the lambda 1 subtype are much more frequent than those of the other subtypes (lambda 2,lambda 3) in antibodies (Ab) to those few antigenic structures that are known to elicit responses, in which lambda chains are the predominant type of light chain [(4-hydroxy-3-nitrophenyl)acetyl (NP) and dextran]. The reason for the frequency differences are not understood, and the large difference between the lambda 1 and lambda 3 frequencies is particularly puzzling, because in nearly all (about 95%) chains of these subtypes the N-terminal 97 or 98 amino acids are endoded by the same V lambda-gene segment. In an effort to identify an Ab response that has different lambda subtype frequencies, we analyzed the light chains of the Ab made by BALB/c and B6 mice in response to 2,4-dinitrophenylated chicken gamma globulin (DNP-CGG). We found that approximately 40% of the elicited anti-DNP molecules had lambda chains and of these approximately 40% were of the lambda 2 or lambda 3 subtype. Polyacrylamide gel electrophoresis indicated that the lambda 2 and lambda 3 chains were about equally abundant. Similar lambda subtype frequencies were found in the anti-DNP Ab produced by the hybridoma made with spleen cells from the same immunized mice. In the anti-DNP Ab elicited by DNP-CGG and in the anti-NP Ab elicited by NP-CGG the different lambda subtype frequencies (lambda 1/lambda 2 + lambda 3 = ca. 1.0-1.5 in anti-DNP and ca. 30 in anti-NP) were unaffected by immunizing mice with each of these antigens alone or with a mixture of the two. This finding, though preliminary, suggests that isotype-specific regulatory T cells are not responsible for the markedly different lambda subtype frequencies in anti-DNP and anti-NP Ab.

Effect of vitamin E supplementation on serum and high-density lipoprotein-cholesterol in renal patients on maintenance hemodialysis

A significant increase in high-density lipoprotein-cholesterol after the ingestion of short-term megadoses of vitamin E has been documented in the recent literature. No attempt has been made to examine the effect of vitamin E supplementation on the serum lipids in chronic renal patients undergoing maintenance hemodialysis. This patient group typically exhibits subnormal high-density lipoprotein-cholesterol levels which may be a factor responsible for their increased mortality rate from atherosclerosis. In the present study, seven male renal patients on dialysis were given 600 IU of vitamin E daily for 4 wk. The level of total, free, and esterified cholesterol and triglyceride in whole serum and high-density lipoprotein were measured pre- and postregimen. No significant change was noted in any of the parameters examined for the group as a whole. Our results suggest that short-term high-dose vitamin E ingestion is unlikely to benefit the majority of renal patients on maintenance hemodialysis in regards to their circulating levels of high-density lipoprotein-cholesterol.

Characterization of the individual phospholipids and their fatty acids in serum and high-density lipoprotein of the renal patient on long-term maintenance hemodialysis

This study characterized the individual phospholipids within total serum and HDL in the renal patient on long-term maintenance hemodialysis relative to matched controls. The fatty acid composition of these individual phospholipids was also determined by using TLC and gas-liquid chromatography in combination. In agreement with previous findings, our patient group had HDL-cholesterol levels 36% below and total phospholipid levels 30% lower than matched controls. Total serum PE but not HDL-PE was significantly elevated (by 30%) in the serum of the patient group due to a rise in diacyl PE. Significantly reduced HDL-SPH levels (by 41%) and a 31% decrease in HDL-PC levels were noted in the patient group. Considerable differences in the individual fatty acids (as weight percent) of the patient vs. control groups were observed. The percent of 16:0 (palmitate) and 18:0 (stearate) was significantly elevated in the PE of the patient group whereas 18:1 (octadecenoate) was generally elevated in all phospholipids. The weight percent of 18:2 (linoleate) was moderately higher in the PE and Pl of the patient group. Absolute levels of selected fatty acids in PC were generally depressed in the patient HDL relative to control, although significantly so only in the case of 16:0 and 20:4 (arachidonate). In keeping with the total PE levels in whole serum, all fatty acids were elevated in the patient group relative to controls. These results indicate that alterations in certain individual phospholipids and their fatty acids exist in renal patients on dialysis compared to matched controls.

The aldolase-binding site of the human erythrocyte membrane is at the NH2 terminus of band 3

Band 3 is the predominant membrane-spanning polypeptide and the mediator of anion transport in the human erythrocyte. In addition, it provides the sites of association for fructose 1,6-bisphosphate aldolase and other cytoplasmic proteins with the membrane. The aldolase-binding activity of water-soluble fragments of band 3 was measured by their inhibition of aldolase catalytic activity and by their displacement of aldolase from ghosts. At saturation, the binding of one band 3 or certain of its fragments per aldolase molecule partially inhibited the catalytic activity and band 3 binding of the unliganded subunits of the tetramer through an apparently cooperative mechanism. An NH2-terminal 23,000-dalton fragment generated by S-cyanylation of the cytoplasmic pole of band 3 was approximately 20% as avid in binding aldolase as was native band 3. Several fragments cleaved from the NH2-terminal portion of the 23,000-dalton peptide by trypsin, mild acid hydrolysis, and cyanogen bromide digestion all bound aldolase, while fragments from the rest of the polypeptide were essentially inactive. The first 31 residues of band 3 contained 16 Asp plus Glu, no basic residues, and a blocked alpha-amino terminus. The highly acidic composition of this region is consistent with the strongly electrostatic character of the interaction between band 3 and aldolase, presumably at the strongly basic catalytic center of the enzyme. We conclude that the NH2-terminal region of band 3 bears the membrane-binding site for aldolase.

Effect of prolactin on the secretion of dehydroepiandrosterone (DHEA), its sulfate (DHEA-S), and cortisol by the human fetal adrenal in vitro

The effect of prolactin on the secretions of dehydroepiandrosterone (DHEA) and its sulfate (DHEA-S) as well as that of cortisol were studied in vitro in order to investigate the possible regulatory role of prolactin on steroidogenesis of the human fetal adrenal at mid-gestational age. The addition of 0.5 microgram/ml of human prolactin to the incubation medium produced a significant (P less than 0.05) increase in DHEA, DHEA-S, and cortisol secretion. These results indicate that prolactin has a regulatory role in steroidogenesis in the human fetal adrenal at mid-gestation.

Radiation therapy of nasopharyngeal carcinoma

Carcinoma of the nasopharynx is one of the most frequent malignant tumors in the southern parts of China. A total of 3 263 cases treated with irradiation in the course of the thirty years since the Liberation have been analysed retrospectively. The 5-year survival rate has risen from 27.7 per cent for cases treated during 1955 to 1960 to 54 per cent for those treated in 1973. The technique of irradiation is described, emphasizing the importance of suitable techniques for the treatment of the cervical lymph nodes. The value of elective irradiation of cervical regions not involved clinically is elucidated. Finally, the causes of failure of treatment are discussed.

Arrangement of glucose residues in the lipid-linked oligosaccharide precursor of asparaginyl oligosaccharides

The lipid-linked oligosaccharide synthesized in vitro, in the presence of 1.0 microM UDP-[3H]Glc, GDP-[14C]Man, and UDP-GlcNAc has been isolated and the structure of the oligosaccharide has been analyzed. The oligosaccharide contains 2 N-acetylglucosamine, 9 mannose, and 3 glucose residues. The N-acetylglucosamine residues are located at the reducing terminus. The 3 glucose residues are arranged in a linear order at one of the nonreducing termini in the sequence Glc 1,2--Glc 1,3--Glc--(Man)9 (GlcNAc)2. The structural analysis was made possible largely by the availability of glucosidase preparations of fungal anad microsomal origin which remove glucose residues from the oligosaccharide without releasing mannose residues.

Effects of UDP-glucose addition on the synthesis of mannosyl lipid-linked oligosaccharides by cell-free fibroblast preparations

The pattern of mannosyl lipid-linked oligosaccharides synthesized by cell-free enzyme preparations from cultured fibroblasts is altered substantially when 0.2 muM UDP-glucose is added to the incubation medium. Inclusion of UDP-glucose results in the appearance of a new labeled oligosaccharide, which is 1 or 2 glycose units larger than the lipid-linked oligosaccharide synthesized in the presence of only GDP-mannose (2 muM) and UDP-N-acetylglucosamine (20 muM). Label from UDP-[3H]glucose is incorporated into the same larger oligosaccharide size class. The results can be explained most easily by assuming that the new mannosyl lipid-linked oligosaccharide contains 1 or 2 glucose residues in addition to 5 to 6 mannose residues. The results are compatible with the recent finding by Spiro et al. (Spiro, M.J., Spiro, R.G., and Bhoyroo, V.D. (1976) Fed Proc. 35, 1375; Spiro M.J. Spiro, R.G., and Bhoyroo, V.D. (1976) J. Biol. Chem. 251, 6400-6408; Spiro, R.G., and Spiro, M.J. AND Bhoyroo, V.D. (1976) J. Biol. Chem. 251, 6409-6419; Spiro, M.J., Spiro R.G., and Bhoyroo, V.D. (1976) J. Biol. Chem. 251, 6420-6425) that naturally occurring mannosyl lipid-linked oligosaccharides contain glucose. In addition to being incorporated into lipid oligosaccharides, glucose residues are also incorporated into endogenous glycoproteins. Incorporation of glucose into glycoproteins that give rise to pronase glycopeptides of the typical asparagine-linked size classes is almost completely dependent on the presence of GDP-mannose.

Renal pelvic tumour associated with analgesic abuse

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