[Effect of artemisinin on ischemia/reperfusion injury of isolated rat myocardium]

OBJECTIVE

To observe the effect of artemisinin on the ischemia/reperfusion injury of the iisolated rat myocardium and to preliminarily study the possible mechanism.

METHOD

Fifty Wistar rats were randomly divided into 5 groups: a control group, an ischemia/reperfusion (I/R) group, and 3 artemisinin (AS) groups (10, 100, 1000 micromol x L(-1)), 10 rats in each group. Ischemia/reperfusion injury of the isolated rat myocardium was induced by a Langendorff system. The electrocardiogram, the cardiac functional parameters, coronary flow, and the activities of LDH (lactate dehydrogenase), CPK (creatine phosphokinase), SOD (superoxide dis-mutase) and the level of malondiadehyde (MDA) in myocardial tissue, and the myocardial ultrastructures were investigated.

RESULT

AS (10,100 micromol x L(-1)) could significantly improve the index of the myocardial function (+/- dp/dt(max), LVSP) after the ischemia/reperfusion, increase the coronary flow, decrease the leakage of LDH and CPK, and increase the SOD activity and decrease the MDA level in cardiac tissues, and alleviate the myocardial ultrastructure injury. But, AS (1000 micromo x L(-1)) did not have the above effects.

CONCLUSION

AS (10, 100 micromol x L(-1)) alleviate the myocardial ischemia/reperfusion injury in rats. The mechanism may be related to its functions of antioxidation and scavenging free radicals.

[Effects of electroacupuncture of different frequencies on slimming effect in the rat of experimental obesity]

OBJECTIVE

To compare the slimming effects of electroacupuncture of different frequencies.

METHODS

The rats were randomly divided into a control group, a model group, an acupuncture group I (30 Hz), and an acupuncture group II (100 Hz). Acupoints selected were "Housanli" (ST 36), "Sanyinjiao" (SP 6), "Guanyuan" (CV 4), "Zhongwan" (CV 12). The changes of Lee's index, fat weight around the left kidney and the volume of the fat cell, blood lipids, insulin and leptin before and after treatment were compared.

RESULTS

Compared with the model group, Lee's index, fat weight around the left kidney and the volume of the fat cell, blood lipids significantly changed in the two acupuncture groups (P<0.01), with the acupuncture group II being more change than that of the acupuncture group I (P<0.05); and compared with the model group, the leptin level decreased in the two acupuncture group (P<0.01) and the serum insulin level decreased (P<0.05) , with no significant difference between the acupuncture group I and the acupuncture group II (P>0.05).

CONCLUSION

Electroacupuncture of different frequencies has different effects on fat metabolism in fat rats, and electroacupuncture of 100 Hz has a better effect than 30 Hz on obesity.

Identification of quantitative trait loci associated with resistance to brown planthopper in the indica rice cultivar Col.5 Thailand

The brown planthopper (BPH) is one of the most serious insect pests of rice throughout Asia. In this study, we constructed a linkage map to determine the locus for BPH resistance gene, using an F(2) population from a cross between a resistant indica cultivar, 'Col.5 Thailand', and a susceptible cultivar '02428'. Insect resistance was evaluated using 147 F(3) families and the genotype of each F(2) plant was inferred from the phenotype of corresponding F(3) families. Two QTLs was detected on chromosome 2 (explains 29.4% phenotypic variation) and 6 (46.2% variation explained) associated with resistance to BPH in the mapping population. Comparison of the chromosomal locations and reactions to BPH biotypes indicated that the gene on chromosome 6 is different from at least 18 of the 19 previously identified BPH resistance genes. These two genes have large effects on BPH resistance and may be a useful BPH resistance resource for rice breeding programs.

A Novel Small-Molecule Inhibitor of Transforming Growth Factor β Type I Receptor Kinase (SM16) Inhibits Murine Mesothelioma Tumor Growth In vivo and Prevents Tumor Recurrence after Surgical Resection

Malignant mesothelioma is an aggressive and lethal pleural cancer that overexpresses transforming growth factor beta (TGFbeta). We investigated the efficacy of a novel small-molecule TGFbeta type I receptor (ALK5) kinase inhibitor, SM16, in the AB12 syngeneic model of malignant mesothelioma. SM16 inhibited TGFbeta signaling seen as decreased phosphorylated Smad2/3 levels in cultured AB12 cells (IC(50), approximately 200 nmol/L). SM16 penetrated tumor cells in vivo, suppressing tumor phosphorylated Smad2/3 levels for at least 3 h following treatment of tumor-bearing mice with a single i.p. bolus of 20 mg/kg SM16. The growth of established AB12 tumors was significantly inhibited by 5 mg/kg/d SM16 (P < 0.001) delivered via s.c. miniosmotic pumps over 28 days. The efficacy of SM16 was a result of a CD8+ antitumor response because (a) the antitumor effects were markedly diminished in severe combined immunodeficient mice and (b) CD8+ T cells isolated from spleens of mice treated with SM16 showed strong antitumor cytolytic effects whereas CD8+ T cells isolated from spleens of tumor-bearing mice treated with control vehicle showed minimal activity. Treatment of mice bearing large tumors with 5 mg/kg/d SM16 after debulking surgery reduced the extent of tumor recurrence from 80% to <20% (P < 0.05). SM16 was also highly effective in blocking and regressing tumors when given p.o. at doses of 0.45 or 0.65 g/kg in mouse chow. Thus, SM16 shows potent activity against established AB12 malignant mesothelioma tumors using an immune-mediated mechanism and can significantly prevent tumor recurrence after resection of bulky AB12 malignant mesothelioma tumors. These data suggest that ALK5 inhibitors, such as SM16, offer significant potential for the treatment of malignant mesothelioma and possibly other cancers.

Intratracheal inoculation of severe acute respiratory syndrome coronavirus in monkeys Macaca rhesus

An animal model for infection with Severe acute respiratory syndrome coronavirus (SARSCoV) was evaluated in monkeys Macaca rhesus. The monkeys were inoculated into the trachea with NS-I strain of SARS-CoV and the clinical manifestation of the illness was monitored. The clinical samples collected from infected monkeys were examined by immumnofluorescence assay (IFA), pathological inspection, RTPCR, and by virus isolation. The infected animals demonstrated mild clinical symptoms including fever. Two of the six infected monkeys developed fever (1.5 above the level before challenge) on the day 10 post inoculation (p.i.). Although the severe clinical symptoms or mortality were not observed, the virological and histopathological evidences of the illness were evident. The specimens collected from the infected animals showed the presence of SARS-CoV detected by RT-PCR, IFA, and by virus isolation. From the organs examined postmortem, a major pathological change was observed in the lungs. The walls of the alveoli were thicker, infiltrated with inflammation cells and an exudative fluid was found in the alveolar spaces. In addition, some alveolar spaces showed hyaline membrane lining. The results showed that the monkeys infected with SARS-CoV developed the typical SARS according to clinical, virological, and pathological findings.

[Effect of Fuzheng Jiangan formula on liver fibrosis induced by albumin in rats]

OBJECTIVE

To observe the effect of Fuzheng Jiangan formula( FZJGF) on liver fibrosis using immune induced liver fibrosis rat model.

METHOD

The rat models with immunity liver fibrosis were induced by the human serum albumin. Rats were treated with normal saline, FZJGF (9. 85,39. 4 g x kg(-1) , two dosage groups) and Colchicine (0. 000 1 g . kg(-1) ). The activities of ALT, AST, contents of ALB and TP, and A/G, The contents of Laminin (LN), Hyaluronic acid (HA) and collagen type IV (IV-C) in rat serum were measured by radioimmunoassay method. The level of hydroxyproline (Hyp) in liver was detected by chemistry method. The pathological changes of liver tissue were observed by HE and Von-Gieson staining.

RESULT

FZJGF could significant decrease the serum activities of ALT and AST, and increase the levels of TP,Alb and ratio A/G. The levels of LN, HA and IV-C were decreased significantly after the treatment using FZJGF. The pathological improvements were observed. FZJGF could markedly alleviate the deposition of collageneous fiber, and reduce the liver pseudoluboli and the fibrosis scores in the liver tissue compared with model group.

CONCLUSION

FZJGF can inhibit formation and development of rat hepatic fibrosis induced by the human serum albumin.

[Analysis on therapeutic effect of substance-partitioned moxibustion at Guanyuan (CV 4) and shenque (CV 8) for treatment of primary dysmenorrhea of cold-damp type]

OBJECTIVE

To observe clinical therapeutic effect of substance-partitioned moxibustion on primary dysmenorrhea (PD). Methods One hundred and thirty-eight cases of PD were randomly divided into two groups, the treatment group (n=78) were treated with substance-partitioned moxibustion at Guanyuan (CV 4) and Shenque (CV 8), once a day; and the control group (n=60) treated with oral administration of Yueyueshu Powder, twice a day, 10 g each time. They were treated for 3 menstrual cycles.

RESULTS

The total effective rate and the index of therapeutic effect were 96.1% and 90.8% in the treatment group, and 88.3% and 76.2% in the control group, respectively, with a significant difference between the two groups (P < 0.05).

CONCLUSION

Clinical therapeutic effect of substance-partitioned moxibustion on primary dysmenorrhea is obvious.

Intracellular TGF-beta receptor blockade abrogates Smad-dependent fibroblast activation in vitro and in vivo

Fibrosis, the hallmark of scleroderma, is characterized by excessive synthesis of collagen and extracellular matrix proteins and accumulation of myofibroblasts. Transforming growth factor-beta (TGF-beta), a potent inducer of collagen synthesis, cytokine production, and myofibroblast transdifferentiation, is implicated in fibrosis. Profibrotic TGF-beta responses are induced primarily via the type I activin-like receptor kinase 5 (ALK5) TGF-beta receptor coupled to Smad signal transducers. Here, we investigated the effect of blocking ALK5 function with SM305, a novel small-molecule kinase inhibitor, on fibrotic TGF-beta responses. In normal dermal fibroblasts, SM305 abrogated the ligand-induced phosphorylation, nuclear import, and DNA-binding activity of Smad2/3 and Smad4, and inhibited Smad2/3-dependent transcriptional responses. Furthermore, SM305 blocked TGF-beta-induced extracellular matrix gene expression, cytokine production, and myofibroblast transdifferentiation. In unstimulated scleroderma fibroblasts, SM305 caused a variable and modest reduction in type I collagen levels, and failed to abrogate constitutive nuclear accumulation of Smad2/3, or alter the proportion of smooth muscle actin stress fiber-positive fibroblasts. In vivo, SM305 prevented TGF-beta-induced Smad2/3 phosphorylation type I collagen (COL1)A2 promoter activation in dermal fibroblasts. Taken together, these results indicate that SM305 inhibits intracellular TGF-beta signaling through selective interference with ALK5-mediated Smad activation, resulting in marked suppression of profibrotic responses induced by TGF-beta in vivo and in vitro.

Relationships between the changes of serum levels of OPG and RANKL with age, menopause, bone biochemical markers and bone mineral density in Chinese women aged 20-75

The correlations between the serum levels of OPG, RANKL with age, menopause, bone markers, and bone mineral densities (BMDs) at the lumbar spine and proximal femur were studied in 504 pre- and postmenopausal Chinese women aged 20-75 years. We found that age was positively and negatively correlated with serum concentrations of OPG (r = 0.442, P < 0.001) and RANKL (r = -0.263, P < 0.001), respectively. Compared with premenopausal women, postmenopausal women showed higher serum OPG levels (107.6 +/- 3.0 vs 72.0 +/- 1.8 pg/ml, P < 0.001), lower serum RANKL concentrations (4.7 +/- 0.4 vs. 5.8 +/- 0.3 pg/ml, P < 0.001) and RANKL/OPG ratios (0.045 +/- 0. 004 vs. 0.099 +/- 0.008, P < 0.001). Neither serum levels of OPG nor RANKL or RANKL/OPG ratio correlated with BMDs after adjustment of age and menopause. They also showed no differences among normal, osteopenic and osteoporotic postmenopausal women. Serum levels of OPG were positively correlated with urinary excretion of NTx (r = 0.1453, P = 0.006). Serum levels of RANKL (r = -0.1928, P < 0.001) and RANKL/OPG ratio (r = -0.1303, P = 0.013) were inversely correlated with serum concentrations of OC. In multiple regression analysis, up to 20% variance (R(2) = 0.106-0.224) of the OPG-RANKL system in peripheral circulation can be explained by age, menopause and bone markers. These results suggest that although serum OPG and RANKL concentrations were unrelated with BMDs, the age- and menopause- dependent changes of serum OPG and RANKL might be a protective mechanism against the accelerated bone loss in postmenopausal women.

Effects of rhM-CSF expressed in silkworm on cytokine productions and membrane molecule expressions of human monocytes

AIM

To study the effects of recombinant human macrophage colony-stimulating factor (rhM-CSF) expressed in silkworm on cytokine productions and membrane molecule expressions of monocytes.

METHODS

The rhM-CSF was added to the human peripheral blood monocyte cultures and 3 d later, the culture supernatants and cells were collected, respectively. TNF-alpha, IL-6, IL-8, and IFN-alpha levels in the supernatants were detected by biological activity test or ELISA and expressions of CD11b, CD16, HLA I, and HLA II on the cellular surface were examined by the method of alkaline phosphatase anti-alkaline phosphatase complex (APAAP).

RESULTS

The rhM-CSF promoted TNF-alpha, IL-6, and IL-8 inductions of monocytes and increased the percentages of CD11b, CD16, HLA I, and HLA II molecule expression on monocytes.

CONCLUSION

The rhM-CSF plays a role in monocyte function up-regulation and has a certain practical value in immunological therapy.

[Effect of oxyphenamone, a new inodilator, on isolated cardiac muscles and arteries]

The cardiotonic and vasodilating effects of oxyphenamone were studied in preparations of rat Langendorff's heart, isolated cardiac muscles of guinea pigs and isolated arteries of dogs. In the preparations of rat Langendorff's heart, infusion of oxyphenamone at 0.1 and 1.0 mumol.L-1 increased myocardial contractility and coronary blood flow moderately and decreased heart rate slightly. Oxyphenamone (1-100 mumol.L-1) increased the contractile force of papillary muscle (PM) and left atrium (LA) of guinea pigs dose-dependently. The positive inotropic effect of oxyphenamone (the ED50 was found to be 18.35 mumol.L-1 in PM and 9.17 mumol.L-1 in LA) was close to that of milrinone, an inhibitor of phosphodiesterase(the ED50 was shown to be 6.23 mumol.L-1 in PM and 4.59 mumol.L-1 in LA). The difference between these two agents is that oxyphenamone decreased the spontaneous pulse rate of right atrium, while milrinone increased it. The vasoconstrictions of dog coronary, basilar and mesenteric arteries induced by KCl, 5-HT and CaCl2 were antagonized non-competitively by oxyphenamone at 1 and 50 mumol.L-1, suggesting that oxyphenamone has a relaxant effect on vascular smooth muscles.

[Effect of oxyphenamone, a new inodilator, on cardiac hemodynamics in normal rat, cat and dog]

For studying the cardiotonic and vasaodilating effect of oxyphenamone in vivo, cardiac hemodynamic variables of anesthetized normal rats, cats and dogs were determined with a polygraph and electromagnetic flowmeters. Intravenous injection of oxyphenamone (0.5-10 mg.kg-1) dose-dependently decreased the mean arterial pressure and systemic vascular resistance moderately and increased cardiac output, myocardial contractile force and +/- dT/dtmax. The blood flow of coronary and femoral arteries increased markedly and their vascular resistance decreased but the blood flow and vascular resistance of cerebral artery did not change. Some species differences were observed in the effect of oxyphenamone on heart rate (HR) and left ventricular pressure (LVP). Oxyphenamone did not influence the HR and LVP in normal cats. It decreased the HR, left ventricular systolic pressure (LVSP) and +/- dP/dtmax, while did not affect the left ventricular end diastolic pressure (LVEDP) in rats. In contrast, administration of oxyphenamone to dogs increased LVSP and +/- dP/dtmax markedly and diminished LVEDP slightly. Oxyphenamone decreased HR slightly at lower dosage (1 and 3 mg.kg-1), but increased heart rate moderately at high dose (6 mg.kg-1) in dogs. These indicate that oxyphenamone has cardiotonic and vasodilating effects in vivo. Whether the effects of oxyphenamone on cardiac hemodynamics would be useful for the treatment of heart failure should be evaluated further.

Detection of the t(2;5)(p23;q35) chromosomal translocation in large B-cell lymphomas other than anaplastic large cell lymphoma

In general, the large cell lymphomas are a cytogenetically heterogeneous group of diseases, and the cytogenetic findings do not correlate with morphological findings in this group of malignant lymphomas. The CD30-positive anaplastic large cell lymphomas, however, are thought to be an exception, with the t(2;5) reported to correlate with the morphological changes of this disease entity. A subgroup of Hodgkin's disease cases have been reported by some investigators to have the t(2;5) translocation, leading to speculation that these two diseases are related. In the current study, the authors used a sensitive reverse transcriptase polymerase chain reaction (RT-PCR) methodology to evaluate the frequency of t(2;5) in 33 cases of large cell lymphoma, of B lineage, other than anaplastic large cell lymphoma. The authors detected evidence of t(2;5) in four of the cases (12%), a frequency similar to that of the authors' previous study of cases of CD30 positive anaplastic large cell lymphoma. Three of the positive large B-cell lymphoma cases were CD30 negative and were morphologically indistinguishable from the cases without evidence of t(2;5). The fourth case had a subpopulation of CD30 positive cells but also did not have morphological features of anaplastic large cell lymphoma. These results would suggest that t(2;5) is not restricted to cases of malignant lymphomas with anaplastic morphology or to CD30 expression.

Absence of the t(2;5) in Hodgkin's disease

The cytogenetics of Hodgkin's disease (HD) is poorly understood. However, a t(2;5) is a common finding in CD30+ anaplastic large cell lymphoma (ALCL), a neoplasm thought by some to be closely related to HD. Recently, the t(2;5) has been cloned and found to represent fusion of the NPM gene with the ALK gene. Using Southern blot hybridization, one group has reported finding rearrangements of NPM in a proportion of cases of both ALCL and HD. In the current study, we used a highly sensitive reverse transcriptase-polymerase chain reaction methodology to analyze 34 cases of HD for the t(2;5). We were unable to find polymerase chain reaction evidence for the t(2;5) in any of the cases of HD, a result significantly different from our previous study of CD30+ non-Hodgkin's lymphomas (P < .02) including ALCL (P < .04), using identical methods. Our results do not support the hypothesis that the t(2;5) represents a common chromosomal abnormality for both HD and ALCL.

Low frequency association of the t(2;5)(p23;q35) chromosomal translocation with CD30+ lymphomas from American and Asian patients. A reverse transcriptase-polymerase chain reaction study

Although cytogenetic data suggest that the t(2;5)-(p23;q35) translocation occurs in many cases of CD30+ lymphomas, the exact frequency of this event is still unknown. To clarify this issue and its epidemiological characteristics, we examined 37 formalin-fixed, paraffin-embedded specimens of CD30+ lymphomas from the United States and Hong Kong by reverse transcriptase-polymerase chain reaction (RT-PCR) for the status of the NPM and ALK genes, which are typically juxtaposed by the t(2;5) translocation. Thirty-four cases were classified as anaplastic large cell lymphomas (ALCL), 2 cases as non-anaplastic large cell lymphomas (LCL), and 1 case as the small cell variant of CD30+ lymphoma. The t(2;5) translocation was detected in 6 cases (16%), including 3 of 18 American patients and 3 of 19 cases from Hong Kong. All cases had a 185-bp NPM RT-PCR product as detected by Southern blot analysis, indicating adequate preservation of mRNA. The 6 positive cases were among 4 of 34 adult lymphomas, as compared with 2 of 3 childhood cases. Five of 17 T-lineage cases were t(2;5)-positive, compared with 1 of 15 B-lineage cases and none of the 5 null-cell or mixed lineage cases. Our results therefore show that t(2;5) occurs at a low frequency among CD30+ lymphomas, at least in our adult-dominated series.

Infrequent association of Epstein-Barr virus with CD30-positive anaplastic large cell lymphomas from American and Asian patients

CD30 (Ki-1)-positive anaplastic large cell lymphoma (CD30+ ALCL) is a morphologically and immunophenotypically distinct subset of non-Hodgkin's lymphoma. Although the presence of Epstein-Barr virus (EBV) has been well documented in a significant proportion of cases of Hodgkin's disease, another CD30+ malignancy, few studies have examined the association of EBV with CD30+ ALCL. These latter studies have produced conflicting findings. To further investigate the existence of a putative association of EBV with CD30+ ALCL, and whether this association, if present, shows geographic variation, we examined 34 formalin-fixed, paraffin-embedded specimens from cases of CD30+ ALCL from the United States and Hong Kong. Immunophenotypically, 15 cases were of B lineage, 15 cases were of T lineage, one case expressed both B- and T-cell markers, and three were of null lineage. A highly sensitive in situ hybridization method was performed with use of an antisense oligonucleotide probe to the EBV-encoded RNA (EBER-1). EBV-RNA was identified in 3 of 14 CD30+ ALCL specimens from Hong Kong patients and in 1 of 20 from the American patients. The EBER-1 signal was present in all or virtually all of the tumor cell nuclei in the three EBV-RNA-positive CD30+ ALCL Hong Kong cases, but was only focally present in the single EBV-positive American case. The latent membrane protein-1 (LMP1) of EBV was identified in only one of the four positive cases, a Hong Kong case. Our results suggest that in contrast to Hodgkin's disease, EBV has no significant association with CD30+ ALCL.

Cellular rejection in discordant xenografts when hyperacute rejection is prevented: analysis using adoptive and passive transfer

Hyperacute rejection of discordant xenografts occurs rapidly, precluding cellular infiltration. Thus the role of cellular rejection in discordant xenografts is debated. Using adoptive transfer of sensitized splenocytes and passive transfer of sensitized serum, we evaluated the influence of cellular and humoral elements on cellular infiltration and rejection in the guinea-pig-to-rat discordant xenograft model. Guinea-pig hearts were transplanted into Lewis rats. Pretransplant, rats underwent splenectomy and plasma exchange and were started on daily cobra venom factor injections. Xenografts rejected faster after adoptive (1, 2, 2 and 2 days) or passive (1, 1, 2 and 2 days) transfer than controls (4, 4, 4 and 4 days; p < 0.05). Macrophages and neutrophils were predominant in early prerejection specimens. Over time, cellular infiltrates were dominated by mononuclear cells. Natural killer cells were present in all groups, as were interleukin 2 receptor positive cells. Our data suggest that either sensitized serum or sensitized cells are capable of initiating an accelerated rejection characterized by cellular infiltration. Despite subtle differences, the population of infiltrating cells was similar in each group. Thus, although rejection may be initiated by either cellular or humoral influences, the ultimate result is the same. We have, therefore, established a small animal model to study cellular rejection in discordant xenografts. This model will help evaluate the role of cell subsets and xenoantibodies in xenograft rejection and will help determine the precise relationship between the two when hyperacute rejection is prevented.

The immunopathology of cardiac xenograft rejection in the guinea pig-to-rat model

The mechanisms underlying rejection by rats of vascularized guinea pig xenografts have been controversial. The aim of this study was to define, using sequential immunopathologic analysis, the contributions of xenoreactive antibody, complement, and effector cells to the rejection of guinea pig cardiac xenografts by Lewis rats. In untreated recipients, hyperacute rejection of guinea pig cardiac xenografts occurred in 20 +/- 10.2 min and was characterized by focal endothelial deposition of IgM and by diffuse deposition of C3. IgG was not localized to endothelial surfaces, but was present in the same locations as albumin, suggesting that the accumulation of IgG might reflect nonspecific leakage of plasma proteins from blood vessels. No polymorphonuclear or monocytic infiltrate was observed. Depletion from rats of xenoreactive antibody to undetectable levels prolonged the survival of guinea pig cardiac xenografts, but did not prevent hyperacute rejection; the rejected xenografts contained deposits of C3 along the microvasculature but no deposits of IgM or IgG. No cellular infiltrate was observed. Depletion of complement with cobra venom factor prolonged the survival of xenografts up to 96 hr. Xenograft tissues from complement-depleted animals had diffuse deposits of IgM along the microvasculature, but no detectable deposits of C3 or IgG were noted. Graft tissues obtained at various times after transplantation into complement-depleted animals revealed cellular infiltrates consisting of granulocytes, monocytes, and lymphocytes, but few cells bearing an NK cell phenotype. Our findings are consistent with the concept that complement activation is essential for the hyperacute rejection of discordant xenografts, and that in this particular model complement activation can proceed without the involvement of antibody. However, our findings also suggest that xenoreactive antibody contributes to hyperacute rejection and, along with effector cells, contributes to the later rejection of a xenograft when hyperacute rejection has been averted. Finally, we show that when hyperacute rejection is avoided, a form of vascular rejection occurs in which certain of the pathologic features--i.e., interstitial hemorrhage, interstitial edema, and thrombosis--are very similar to those observed in hyperacute rejection. Whether this form of rejection is a delayed form of the process that leads to hyperacute rejection or a novel pathologic process of graft rejection has yet to be determined.

Protective effect of puerarin against myocardial reperfusion injury. Myocardial metabolism and ultrastructure

To ascertain the beneficial effect of puerarin on the myocardium against reperfusion injury, studies on myocardial metabolism and ultrastructure were made. Twelve dogs divided into two equal groups were placed on moderate hypothermic cardiopulmonary bypass, and their hearts were subjected to 140 minutes cold cardioplegic arrest and 60 minute reperfusion. In the control group, the hearts were perfused with crystalloid cardioplegic solution (CPS) every 20 minutes during arrest. In the treated group, the hearts received CPS containing puerarin (2 mg/kg). Myocardial oxygen consumption, lactate production, creatine phosphokinase (CPK) release, water content and ultrastructural alterations were determined before ischemia, during cardiac arrest and at reperfusion. The results showed that intermittent infusion of CPS containing puerarin significantly decreased myocardial lactate production during ischemia, as well as myocardial oxygen consumption, CPK release and water content during reperfusion. Under electronmicroscopy, the degree of ischemic damage judged by a scoring method was less pronounced in the puerarin group than in the control. The authors conclude that puerarin has protective effects on the function of hearts that have undergone long periods of arrest and reperfusion.