Myostatin inhibits insulin-like growth factor 1-dependent citrate secretion and osteogenesis via nicotinamide adenine dinucleotide phosphate oxidase-4 in a mouse mesenchymal stem cell line

Citrate is an indispensable component of bone. Reduced levels of citrate in bone and serum are reported in the elderly and in osteoporosis patients. Myostatin (Mstn) is implicated in skeletal homeostasis, but its effects on osteogenesis remain incompletely understood. Nox4 has critical roles in bone homeostasis. TGF-β/Mstn-associated Smad2/3 signaling has been linked to Nox4 expression. Insulin-like growth factor (IGF-1) has been shown to counteract many regulatory effects of Mstn. However, the crosstalk among Mstn, IGF-1, and Nox4 is not well understood; the interactive effects of those factors on citrate secretion, osteogenic differentiation, and bone remodeling remain unclear. In this study, we demonstrated that osteogenic differentiation induced an IGF-1-dependent upregulation of citrate secretion that was suppressed by Mstn. Inhibition of Nox4 prevented Mstn-induced reduction of citrate secretion. In addition, Mstn reduced bone nodule formation; these changes were prevented by Nox4 inhibition. Moreover, Mstn increased the ratio of RANKL to OPG mRNAs to favor osteoclast activation. These results indicate that Mstn negatively regulates osteogenesis by increasing levels of Nox4, which reduced IGF-1 expression, citrate secretion, and bone mineralization while also altering the RANKL to OPG ratio. These findings provide new and highly relevant insights into the osseous effects of myostatin.

[Novel coronavirus pneumonia (COVID-19) CT distribution and sign features]

Objective: To investigate the imaging findings of 2019 novel coronavirus pneumonia (COVID-19). Methods: From January 20 to February 5, 2020, a total of 130 patients diagnosed with COVID-19 from seven hospitals in China were collected. The imaging data were reviewed and analyzed in detail. Results: (1) Distribution: the lesion detected in the lung unilaterally in 14 cases (10.7%) and bilaterally in 116 cases (89.3%). According to the distribution in the lobes of the lung, all cases could be classified into subpleural distribution (102 cases, 78.4%), centrilobular distribution (99 cases, 76.1%) and diffused distribution (8 cases, 6.1%). (2) Number of lesions: single lesion 9 cases (6.9%); multiple lesions 113 cases (86.9%), diffuse lesions 8 cases (6.1%). (3) Imaging density: 70 cases (53.8%) of ground-glass opacity (GGO), 60 cases (46.2%) of GGO+consolidation. (4) Accompanying signs: 100 cases (76.9%) with vascular thickening, 98 cases (75.3%) with "pleural parallel sign" ; " intralobular septal thickening" in 100 cases (76.9%); "halo sign" in 13 cases (10%); "reversed-halo sign" in 6 cases (4.6%); pleural effusion in 3 cases (2.3%), and pneumatocele in 2 cases (1.5%); no case with pulmonary cavity. Among 35 patients that underwent follow-up CT, 21 patients (60%) improved while 14 (40%) exacerbated. Conclusions: COVID-19 imaging characteristic mainly has subpleural, centrilobular and diffused distribution. The first two distributions can overlap or progress to diffused distribution. In the later period, it was mainly manifested as organizing pneumonia and fibrosis. The most valuable characteristic is the pleural parallel sign.

AdipoRon prevents myostatin-induced upregulation of fatty acid synthesis and downregulation of insulin activity in a mouse hepatocyte line

Liver diseases such as non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are characterized by excess hepatic accumulation of lipid droplets and triglycerides which are associated with defective insulin action. Myostatin (Mstn) and adiponectin, secreted by muscle cells and adipocytes, respectively, play important roles in regulating insulin signaling and energy metabolism. The mechanisms underlying the actions of Mstn and adiponectin remain largely unknown. Moreover, the interactions between Mstn and adiponectin in regulating gene expression critical for fatty acid metabolism and insulin action in hepatocytes have not been investigated. The effects of Mstn and AdipoRon, a synthetic adiponectin receptor agonist that is orally active, alone or in combination, on hepatic gene expression and function was investigated. While Mstn increased fatty acid (FA) accumulation and desensitized cellular responses to insulin, AdipoRon protected against Mstn-induced defects in hepatic gene expression and function. In addition, these effects of Mstn were associated with reduced AMPK and PPARα activities which were reversed by AdipoRon. Finally, AdipoRon was able to prevent Mstn-induced activation of the Smad2/3 pathway. These data suggest crosstalk between Mstn-induced Smad2/3 and adiponectin-induced AMPK/PPARα pathways, which may play important roles in the regulation of hepatic gene expression critical for FA metabolism and insulin signaling. In addition, the data suggest that AdipoRon, as an adiponectin receptor agonist, may serve a therapeutic role to reduce the hepatic contribution to the disorders of fat metabolism and insulin action.

The oocyte-to-baby rate of day 2, day 3 versus day 5 embryo transfer: a retrospective study

OBJECTIVES

To investigate whether the time of embryo transfer (ET) affect the oocyte-to-baby rate.

MATERIALS AND METHODS

The database was retrospectively analyzed including total number of oocytes collected and corresponding oocyte-to-live baby born (LBB) rate. Then the relationship between different time of embryo transfer and oocyte-to-baby rate was compared. In a year period all patients undergoing infertility treatment were included in the study. The outcome parameters were total number of oocytes collected and corresponding oocyte-to-LBB.

RESULTS

For patients under the age of 35 years, there was no increase in oocyte-to-LBB regardless of the time of ET. For patients older than 35 years, the oocyte use rate increased significantly when embryo was transferred on day 2. Oocyte-to-baby rates were also analyzed after grouping patients on the number of oocytes retrieved per cycle. For patients < 35 years, the oocyte- to -LBB rate increased significantly on day 3 if < ten oocytes were obtained. whereas for patients > 35 years, the oocyte-to-baby rate was best on day 2 when about 15 oocytes were retrieved.

CONCLUSIONS

This retrospective analysis demonstrated the relationship between the time of ET and ooctye-to-baby rate that is indicative of a more biologically efficient reproductive system.

Lymphotactin cotransfection enhances the therapeutic efficacy of dendritic cells genetically modified with melanoma antigen gp100

Lymphotactin (Lptn) is a C chemokine that attracts T cells and NK cells. Dendritic cells (DC) are highly efficient, specialized antigen-presenting cells and antigen-pulsed DC has been regarded as promising vaccines in cancer immunotherapy. The aim of our present study is to improve the therapeutic efficacy of DC-based tumor vaccine by increasing the preferential chemotaxis of DC to T cells. In this study, Lptn and/or melanoma-associated antigen gp100 were transfected into mouse bone marrow-derived DC, which were used as vaccines in B16 melanoma model. Immunization of C57BL/6 mice with DC adenovirally cotransfected with Lptn and gp100 (Lptn/gp100-DC) could enhance the cytotoxicities of CTL and NK cells, increase the production of IL-2 and interferon-gamma significantly, as compared with immunization with gp100-DC, Lptn-DC, LacZ-DC, DC or PBS counterparts. The Lptn/gp100-DC immunized mice exhibited resistance to tumor challenge most effectively. It was found that the tumor mass of mice vaccinated by Lptn/gp100-DC showed obvious necrosis and inflammatory cell infiltration. In vivo depletion analysis demonstrated that CD8(+) T cells are the predominant T cell subset responsible for the antitumor effect of Lptn/gp100-DC and CD4(+) T cells were necessary in the induction phase of tumor rejection, while NK cells were less important although they participated in the antitumor response either in the induction phase or in the effector phase. In the murine model with the pre-established subcutaneous B16 melanoma, immunization with Lptn/gp100-DC inhibited the tumor growth most significantly when compared with other counterparts. These findings provide a potential strategy to improve the efficacy of DC-based tumor vaccines.

Intrasplenic transplantation of IL-18 gene-modified hepatocytes: an effective approach to reverse hepatic fibrosis in schistosomiasis through induction of dominant Th1 response

Hepatic fibrosis is a common outcome of chronic liver diseases. In schistosomiasis, chronic parasite egg-induced granuloma formation can lead to fibrosis, which is immunologically characterized by the dominant Th2 response. Recently, it has been shown that gene therapy is an attractive approach for the treatment of hepatic fibrosis. To investigate the antifibrotic effects of IL-18 gene transfer, a normal murine liver cell line BNL.CL2 was transfected with recombinant adenovirus encoding mouse IL-18, and then intrasplenically transplanted into mice infected with Schistosoma japonicum (S. japonicum). Our data show that IL-18 gene-modified hepatocytes intrasplenically transplanted into mice can effectively express IL-18 in the liver and in peripheral blood. Intrasplenic transplantation of IL-18 gene-modified hepatocytes into S. japonicum-infected mice could result in a significantly increased IFN-gamma and IL-2 but decreased IL-4 and IL-10 concentration both in the liver and in the serum, suggesting that the dominant Th2 response in mice with schistosomiasis could be reversed by this intervention. Consistent with the changes in Th1 and Th2 cytokine production, mice intrasplenically transplanted with IL-18 gene-modified hepatocytes developed much less hepatic fibrosis at 20 weeks after infection, which was evaluated by liver content of hydroxyproline, collagens, and hepatic mRNA expression of procollagens. These data indicate that intrasplenic transplantation of IL-18 gene-modified hepatocytes can be a candidate for therapeutic intervention in hepatic fibrosis through induction of a dominant Th1 response.

Evidence for inhibition of low density lipoprotein oxidation and cholesterol accumulation by apolipoprotein H (beta2-glycoprotein I)

Low density lipoprotein (LDL) oxidation and lipid accumulation are thought to enhance the progression of atherosclerosis. Apolipoprotein H (apoH) has been implicated in the development of human atherosclerosis. However, the roles of apoH in the oxidative modification of LDL and cellular accumulation of lipid constituents remained uncharacterized. In this study, the level of plasma apoH was found to be significantly associated with the oxidative susceptibility of LDL in human subjects. Plasma levels of apoH were positively correlated with the lag time but negatively correlated with LDL oxidation rate in conjugated diene formation. By using a J774 A.1 macrophage culture system, we found that apoH could not only inhibit the formation of conjugated diene and thiobarbituric acid-reactive substances, but also reduce the electrophoretic mobility of oxidized LDL. Furthermore, apoH decreased cellular accumulation of cholesterol via a reduction in cholesterol influx and an increase in cholesterol efflux. This is the first demonstration that apoH appears to have "antioxidant"-like effects on LDL oxidation. The results also suggest that apoH can inhibit the translocation of cholesterol from extracellular pools to macrophages, suggesting that apoH may play an important role in the prevention of atherosclerosis.

Intratumoral IL-18 gene transfer improves therapeutic efficacy of antibody-targeted superantigen in established murine melanoma

Antibody-targeted superantigen C215Fab-SEA is a fusion protein of staphylococcal enterotoxin A (SEA) and the Fab region of the tumor-reactive C215 mAb. It can trigger CTL against C215 antigen-positive tumor cells and induce tumor-suppressive cytokines. However, the antitumor effect of C215Fab-SEA is not satisfactory because of suboptimal production of Th1 cytokines after repeated administration. Interleukin 18 (IL-18) is a novel cytokine with profound effects on Th1 cellular response. In this study, we showed that adenovirus-mediated intratumoral IL-18 gene transfer strongly improved the therapeutic efficacy of C215Fab-SEA in the pre-established C215 antigen-expressing B16 melanoma murine model. More significant tumor inhibition and prolonged survival time were observed in tumor-bearing mice received combined therapy of C215Fab-SEA and Ad IL-18 than those of mice treated with C215Fab-SEA or AdIL-18 alone. Combination therapy augmented NK and CTL activities of tumor-bearing mice more markedly. The production of IL-2 and IFN-gamma also increased more significantly. More potent antitumor effect of combined therapy was observed in IL-10 KO mice with enhanced Th1 response. Our data demonstrated that the antitumor effect of C215Fab-SEA immunotherapy could be potentiated significantly by combination with intratumoral IL-18 gene transfer through more efficient activation of Th1 immune responses.

Familial defective apolipoprotein B-100: detection and haplotype analysis of the Arg(3500)-->Gln mutation in hyperlipidemic Chinese

Familial defective apolipoprotein (apo) B-100 (FDB) is caused by R3500Q mutation of the apo B gene resulting in decreased binding of LDL to the LDL receptor. Two other apo B mutations, R3500W and R3531C, affecting binding are known to date. We screened the apo B gene segment around codon 3500 by heteroduplex analysis and single strand conformation polymorphism (SSCP) analysis in a total of 373 hyperlipidemic individuals. Two single-base mutations were detected and confirmed by DNA sequencing. One mutation, ACA(3528)-->ACG change, resulted in degenerate codon with no amino acid substitution. The other mutation, CGG(3500)-->CAG mutation, resulted in an Arg(3500)-->Gln substitution (R3500Q). The prevalence of heterozygote in this selected population was 0.3% (95% confidence interval, 0.01-1.5%) for the R3500Q mutation, and 2.4% (95% confidence interval, 1.1-4.5%) for the previously described R3500W mutation. The results suggest that the R3500Q mutation is not a significant factor contributing to moderate hypercholesterolemia in Chinese (P=0.027). Family studies of the R3500Q carrier revealed a further two individuals heterozygous for the mutation, both of whom were hypercholesterolemic. Analysis of the R3500Q allele using six diallelic markers and the 3'HVR marker revealed a haplotype which was the same as that reported in a Chinese American but differed from that reported in a Chinese Canadian. Our data support limited multiple recurrent origins for R3500Q in Chinese population.

Synthesis and antimalarial activity of artemisinin derivatives containing an amino group

In search of water-soluble artemisinin derivatives that are more stable than sodium artesunate, over 30 derivatives containing an amino group (compounds 3-5) were synthesized and tested in mice. All products tested (except 5a and 5b) are the beta isomers. These basic compounds combined with organic acids (oxalic acid, maleic acid, etc. ) to yield the corresponding salts. Generally, the maleates have better solubility in water than the corresponding oxalates. The aqueous solutions of these salts can be kept at room temperature for several weeks without any discernible decomposition. Compounds 3f, 3h, and 3r are much more active against P. berghei than artesunic acid by oral administration and therefore were further tested in monkeys. However, their oral efficacies are poorer than that of artesunic acid against P. knowlesi in rhesus monkeys. It is interesting to note that 3f, 3h, and 3r showed much lower efficacies against P. berghei when they were administered subcutaneously than orally.

Analysis of lipids in non-diabetic patients with acute myocardial infarction

BACKGROUND

The incidence of postinfarct cardiac events can be reduced through secondary prevention by lipid regulation. The relationship between early-detected lipids and prognosis was investigated prospectively in 97 non-diabetic patients with acute myocardial infarction (AMI).

METHODS

Blood samples were analyzed in five evolving stages of AMI: 1) immediately after admission (< 24 hours after the onset of symptoms); 2) on the second day after admission (< 48 hours after the onset of symptoms); 3) on the seventh day after admission; 4) two weeks after the AMI; and 5) three months after the AMI. Cardiac events, including congestive heart failure, reinfarction, unstable angina, ventricular tachyarrhythmia and sudden cardiac death were evaluated at a mean follow-up of 26 months.

RESULTS

Serial measurements in 75 cases with complete follow-up showed that all lipids except lipoprotein(a) had a decline in plasma level after patients were admitted to hospital. The concentrations of lipids three months postinfarct approached the admission values. Age, body mass index, vessel number, severity of vessel disease and the initial values of lipids on admission had no influence on postinfarct cardiac events in these patients.

CONCLUSIONS

The results indicate that the plasma levels of lipids detected within 24 hours after AMI can be used as the baseline lipid levels. Nevertheless, the impact of these lipids on the adverse outcomes in non-diabetic AMI patients should be further studied in a large-scale study.

Results of coronary stenting after delayed angioplasty of the culprit vessel in patients with recent myocardial infarction

Little information is available concerning the effect of late coronary stenting in patients with recent myocardial infarction, especially long-term results. We retrospectively reviewed our results of 57 stent placements in 52 consecutive patients who received stents at an infarct-related lesion 24 hr to 30 days after an acute myocardial infarctions (median, 14 days). The average age was 67 years; 90% were male. Two patients who suffered from acute stent thrombosis received revascularization again and two early deaths were due to refractory cardiogenic shock before discharge. Mean patient clinical follow-up was 18.3 +/- 6.5 months. There were 1 subacute stent thrombosis, 1 cardiogenic death, and 10 patients (20.8%) in total suffering from angina class II to IV. Angiographic follow-up was performed in 36 patients (80%) at a mean of 7.5 +/- 3.1 months. Of these 36 patients, only 1 (3% of the total population undergoing follow-up angiography) had reocclusion at follow-up, but restenosis existed in 18 patients (50%). We conclude that there is still relatively high incidence of angiographic recurrence that is often silent in long-term follow-up, though the long-term result of late stenting in recent MI is low incidence of reocclusion.

Identification and haplotype analysis of apolipoprotein B-100 Arg3500-->Trp mutation in hyperlipidemic Chinese

DNA screening for apolipoprotein (apo) B-100 mutations was performed in hyperlipidemic Chinese. The apo B-100 gene segment surrounding previously identified familial defective apo B-100 (FDB) mutations was amplified by PCR and subjected to single-strand conformation polymorphism (SSCP) analysis. One subject's aberrant SSCP band was cloned and sequenced to study the molecular lesions. A recurrent ArgCGG-to-TrpTGG mutation (R3500W) in the codon 3500 of the apo B-100 gene was identified. The C-to-T transition creates a NlaIII site and permits rapid restriction analysis of the mutation. A total of 373 hyperlipidemic patients and 309 controls were screened for R3500W. Nine unrelated subjects were shown to be heterozygous for the mutation, and no R3500W carriers were found in the control group (P = 0.004). Six polymorphic markers, including five restriction fragment length polymorphisms and one hypervariable repeat region, were used for haplotype analysis on the mutant allele. In two families, the R3500W mutation could be unambiguously assigned to a unique haplotype XbaI-/MaeI+/MspI+/EcoRI+/ Eco57I+/34 3'HVR repeats; in the other seven unrelated heterozygotes, this finding was consistent when an unequivocal haplotype was deduced. The results suggest that all R3500W alleles are identical by descent in our population. The fact that the same mutant allele was identified in other Asians with FDB indicates a common Asian origin for the R3500W mutations.

Polymorphisms of the apolipoprotein B 3' variable number of tandem repeats region associated with coronary artery disease in Taiwanese

We studied the allelic frequency of the variable number of tandem repeats region 3' of the apolipoprotein B gene (apoB 3' VNTR) and its impact on coronary artery disease (CAD) in 150 patients with CAD and 153 normal controls in a Taiwan population. apoB 3' VNTR alleles were classified according to the number of repeats of a 15-bp hypervariable elements (HVE), the sequence of which was determined using the polymerase chain reaction and direct sequencing. Thirteen alleles comprising from 26 to 54 HVEs were identified. The CAD patients had greater heterozygosity (0.58 vs 0.42) and a higher frequency of long (> 36-HVE) apoB 3' VNTR alleles than the controls (18.7% vs 10.8%, p < 0.01). CAD patients with two HVE-36 alleles and no HVE-32 alleles (the two most common forms) had significantly higher concentrations of LDL-cholesterol, apolipoprotein B, and triglycerides, and significantly lower values of HDL-cholesterol and apolipoprotein AI than the control group (p < 0.01 for all comparisons). The length of the apoB 3' VNTR was not correlated with the plasma concentrations of any of the lipids. We conclude that long apoB 3' VNTR alleles occur more frequently in CAD patients, but that apoB 3'VNTR genotypic variation has little impact on the risk of dyslipidemia in Taiwanese.

Restriction fragment length polymorphisms of apolipoprotein B gene in Chinese population with coronary heart disease

Three restriction fragment length polymorphisms (RFLPs), EcoRI (R), Xbal (X), and Mspl (M) of the apolipoprotein (apo)B gene, were studied to determine their distribution frequencies and influence on the lipid profiles in 148 Chinese patients with documented coronary heart disease (CHD) and in 153 healthy subjects. The plasma concentrations of cholesterol and apoB showed no difference between the CHD patients and controls. However, CHD patients had significantly higher concentrations of low-density lipoprotein cholesterol and triglyceride and lower concentrations of high-density lipoprotein cholesterol than the controls. The frequencies of these three apoB RFLPs did not differ between the CHD patients and controls. Compared with South Asians and Caucasians, the Chinese in Taiwan showed a much lower frequency of R-, X+, and M- alleles. There was no evidence of an association between lipid profiles and RFLPs in either CHD patients or controls. The weak association of EcoRI, Xbal, and Mspl polymorphisms of the apoB gene with CHD indicates that the three RFLPs cannot be used as a predictor for the risk of CHD in the Chinese population.

An appraisal of dipyridamole thallium imaging-detected ischemia in Chinese following acute myocardial infarction

BACKGROUND

The detection of objective myocardial ischemia is an important work-up of risk stratification for survivors of acute myocardial infarction (MI). Intravenous dipyridamole thallium scintigraphy was used to identify the prevalence and prognostic value of silent myocardial ischemia (SI) at the early stage in patients after MI.

METHODS

Ninety patients (male/female = 87/3; aged from 36 to 70 years) who succumbed to an episode of MI was recruited in this prospective study. Thallium imaging with reversible or combined defect was defined as presence of SI (Group I), while those with fixed defects or normal images were defined as absence of SI (Group II). Correlation between the patterns of thallium images for postinfarct ischemia and the angiographic lesions was investigated. Also, versatile clinical variables and indexes of adverse cardiac events: unstable angina, CHF, reinfarction, ventricular tachyarrhythmia and sudden death, were evaluated for their influence on patients' prognosis. The average follow-up was 11.6 months.

RESULTS

There were 61 patients in the Group I as compared with 29 patients in the Group II. The difference of Killip functional classification between Group I and Group II patients was not significant (1.33 +/- 0.72 versus 1.07 +/- 0.59). Adverse cardiac event occurred in 30% (27/90) of the patients during follow-up. Cardiac death occurred in 6 cases (7%) and were distributed evenly (3 versus 3) in both groups. Group I patients showed a higher number of nonfatal reinfarctions (8 versus 5) and had more cases of percutaneous coronary angioplasty (11 versus 8) than Group II patients. Only two cases in Group I underwent bypass graft surgery. There was no statistic difference among four patterns of thallium image in the cumulative event-free survival curve. Prior history of CHF, prior MI and higher score index of proximal arterial stenosis were the three significant prognostic predictors for late cardiac events.

CONCLUSIONS

Dipyridamole thallium imaging-detected SI was frequently seen in the Chinese patients following AMI. It was less valuable than prior histories of CHF, prior MI and higher index of proximal arterial stenosis scores in predicting the short-term unfavorable cardiac events in these patients. A large scale analysis and longer follow-up might be required to more accurately determine the role of this exam for the Chinese victims of myocardial infarction.

Restriction fragment length polymorphisms of apolipoprotein B gene in Chinese population with coronary heart disease

Three restriction fragment length polymorphisms (RFLPs), EcoRI (R), Xbal (X), and Mspl (M) of the apolipoprotein (apo)B gene, were studied to determine their distribution frequencies and influence on the lipid profiles in 148 Chinese patients with documented coronary heart disease (CHD) and in 153 healthy subjects. The plasma concentrations of cholesterol and apoB showed no difference between the CHD patients and controls. However, CHD patients had significantly higher concentrations of low-density lipoprotein cholesterol and triglyceride and lower concentrations of high-density lipoprotein cholesterol than the controls. The frequencies of these three apoB RFLPs did not differ between the CHD patients and controls. Compared with South Asians and Caucasians, the Chinese in Taiwan showed a much lower frequency of R-, X+, and M- alleles. There was no evidence of an association between lipid profiles and RFLPs in either CHD patients or controls. The weak association of EcoRI, Xbal, and Mspl polymorphisms of the apoB gene with CHD indicates that the three RFLPs cannot be used as a predictor for the risk of CHD in the Chinese population.

Response of left ventricular ejection performance following balloon valvuloplasty in patients with mitral stenosis

In order to see if any change of left ventricular ejection performance (LEVP) would occur after successful balloon mitral valvuloplasty (BMV), a prospective study on echocardiography and calibrated carotid pulse tractings was performed two days before, two days and then six months after BMV in 24 patients with pure rheumatic mitral stenosis (MS). Echocardiographic parameters representing preload i.e. end-diastolic volume index (EDVI); afterload i.e. end-systolic wall stress (ESS), and the indices of LVEP i.e. ejection fraction (EF), fractional shortening, rate-corrected velocity of circumferential shortening (VCFc) and a ratio of ESS over end-systolic volume index (ESS/ESVI) were measured. A group of 66 normal subjects was used to establish the 95% confidence interval of the echo parameters. The incidence of depressed LVEP in MS patients was about 21% when measured by load-independent index i.e. ESS/ESVI. In the MS group, 7 out 24 (29%) patients achieved an increased cardiac index after BMV. Six (25%) MS patients showed an EF below 95% confidence interval of control (less than 55%) before BMV and, of these 6, only 3 patients increased their EDVI after the BMV. Those who showed an EF greater than or equal to 55% before BMV gave no change in their preload (EDVI) after the BMV. Only one MS patient showed high afterload (ESS) both before and after BMV. However, the ESS/ESVI showed insignificant improvement (p = 0.055) after BMV. It was therefore concluded that (1) a depressed LVEP is frequently seen in patients with MS; (2) LVEP can be improved by BMV in some (21%) patients with MS, and the improvement is not related to the change of preload or afterload but more likely secondary to an increased myocardial contractility.

Frequency and severity of mitral regurgitation one year after balloon mitral valvuloplasty

Mitral regurgitation (MR) was evaluated by Doppler echocardiography in 59 patients with mitral stenosis before, immediately after and 1 year after balloon mitral valvuloplasty (BMV). The severity of MR was graded on a scale from 1+ to 4+. Echocardiographic and hemodynamic variables were analyzed to study the potential factor(s) that might predict the long-term persistence of MR. Echocardiographic variables were mitral valve thickness and motion, subvalvular change, left atrial dimension, commissural calcification and effective balloon/mitral anular diameters. Hemodynamic variables were mitral pressure gradient, pulmonary arterial pressure, ejection fraction, mitral valve area index, age, gender and cardiac rhythm. Mitral valve area index increased from 0.9 +/- 0.5 to 1.5 +/- 0.8 cm2/m2 immediately after BMW, and to 1.4 +/- 0.3 cm2/m2 at 1 year follow-up (p less than 0.01). Immediately after BMV, MR grading did not change in 30 patients (51%), increased by 1+ in 23 patients (39%), by 2+ in 2 patients (3.3%) and by 3+ in 2 patients (3.3%), and decreased by 1+ in 2 others. At 1-year follow-up, only 1 patient with severe MR required valve replacement. Fifty-one patients (88%) had no change in the extent of MR (less than or equal to 1+) and 6 patients (10%) had a 1-grade decrease in their MR; only 1 patient had a 1-grade increase in MR. No clinical or hemodynamic variables or morphologic characteristics of the mitral valve could predict the development of significant MR after BMV. It is concluded that an increment in MR severity less than or equal to 2+ is frequently seen after BMV.(ABSTRACT TRUNCATED AT 250 WORDS)

Usefulness of echocardiography in the prediction of early results of catheter balloon mitral valvuloplasty

Catheter balloon mitral valvuloplasty (BMV) was performed in 50 patients and 32 of them undergoing BMV with double balloon technique were studied to evaluate the usefulness of echocardiography in the prediction of early results of BMV. Five echocardiographic variables including mitral valve motion, mitral valve thickness, subvalvular change, commissural calcification and left atrial dimension were evaluated. Each variable was divided into mild, moderate and severe subgroups. Before valvuloplasty there were no differences in mitral valve area among any subgroup for any variable. After valvuloplasty, variables associated with a greater increase in mitral valve area from mild and moderate subgroups than from severe subgroup included mitral valve motion, mitral valve thickness, and subvalvular change, but not commissural calcification or left atrial dimension. We scored the former 3 variables as 0, 1 and 2 points in the mild, moderate and severe subgroups, respectively. The sums of individual scores in these 3 variables were further divided into 3 groups: 12 patients had a lower score (less than 2), 10 patients had a score of 3-4 and 10 patients had a higher score (greater than 5). Patients with lower scores tended to have greater increases in mitral valve areas after valvuloplasty than those with higher scores. Thus, mitral valve motion, mitral valve thickness and subvalvular change may be useful to predict a greater increase in mitral valve area after valvuloplasty. A lower score of echocardiographic variables anticipates successful balloon mitral valvuloplasty, which may be helpful in patient selection.

Minimal requirement of effective dilation diameter of balloon(s) in percutaneous transluminal mitral valvotomy

40 patients are included to study the minimal requirement of effective dilation diameter of balloon(s) in performing percutaneous transluminal mitral valvotomy (PTMV) to obtain good hemodynamic and long-term follow-up consequences. The patients are divided into 2 groups depending on the ratio of effective dilation diameter of balloon(s) (determined by calculating the cross-sectional area of the oval enveloping the one or two balloons and then taking the diameter of the circle with the same area) to mitral annular diameter (determined by 2-dimensional echocardiography) (Balloon-Mitral Anular Ratio, BMAR). BMAR in group 1 may be equal to or greater than 0.80 or 0.90, BMAR in group 2 may be less than 0.80 or 0.90. From the careful analysis, the statistically significant immediate hemodynamic improvement, e.g. the reduction of trans-valvular pressure gradient, left atrial pressure, pulmonary artery systolic pressure, the increase of mitral valve area, can be obtained even BMAR is less than 0.80. However, the increase of stroke volume index after PTMV can only be obtained with the BMAR equal to or greater than 0.80. The long-term improvement, determined by greater increment of exercise duration, is also only obtained if the BMAR equal to or greater than 0.80 at PTMV. Therefore, we conclude that to obtain the adequate and satisfactory immediate hemodynamic and long-term follow-up results of PTMV, the BMAR must exceed 0.80.

The efficacy and safety of recombinant tissue plasminogen activator infusion in acute myocardial infarction

Recombinant tissue plasminogen activator (rt-PA) is the most promising agent use for salvaging ischemic myocardium in acute infarction. To assess the safety and efficacy of rt-PA thrombolytic therapy, an open label clinical trial was conducted. Patients of acute myocardial infarction with angina, occurring within the five previous hours, was treated with rt-PA 100 mg infusion within three hours; followed with coronary arteriography to assess the patency rate of infarct vessels. Twenty-five cases of acute myocardial infarction were studied over a 10-month period. The patients, 24 male and one female, were aged 58.1 +/- 7.7 years. Rt-PA was given at 3.17 +/- 1.0 hour. Infarct-related vessels had opened in 21/24 cases when examined with coronary arteriogram three hours after infusion. Good antegrade flow of grade 2 to 3 was gained in 20/24 cases, representing an 83% success rate. One patient expired from cardiogenic shock during the infusion; another was expired from noncardiac accident after coronary bypass graft. The total inhospital mortality rate was about 8%. There was no major bleeding complication except in one case with gastrointestinal bleeding requiring transfusion.

IN CONCLUSION

rt-PA is safe and effective in the treatment of acute myocardial infarction in the early stage. Coronary arteriography can be safely delayed until three hours postinfusion, and the achieved reperfusion rate is up to 83%.

Ultrastructure of the daughter sporocyst and developing cercaria of Schistosoma japonicum in experimentally infected snails, Oncomelania hupensis hupensis

Ultrastructure of daughter sporocysts and cercariae of Schistosoma japonicum were studied 2 and 4 months after infection of Oncomelania hupensis hupensis. The body walls of daughter sporocysts are similar at all infectious stages. They consist of an external syncytial tegument on a basement membrane, and an internal cellular subtegument surrounding a body cavity containing developing cercariae. The cercariae embryos develop 2 months after infection from germinal balls in the brood chamber of the daughter sporocyst. They are at first enveloped by a primitive epithelium rising from the daughter sporocyst. Four months after infection, the cercariae were almost fully developed and the primitive epithelium had degenerated. The body wall of the cercaria consists of a thin tegument covered by a surface coat of fibrous material and connected to the subtegumental cells by cytoplasmic processes. The matrix of the tegument contains numerous dense bodies, vacuoles, and spines. Two types of sensory structures - uniciliated and multiciliated - are found at the anterior tip of the cercaria. There are five pairs of penetration gland cells of two distinct types differentiated by the morphology of secretory granules. Flame cells are found in both daughter sporocysts and in cercariae. The cilia of the flame cells are characterized by the typical 9 and 2 cilium pattern.