[Clinical observation of botulinum toxin A injection in the treatment of acute comitant esotropia: a retrospective cohort study]

Objective: To observe the efficacy and safety of botulinum toxin A (BTA) injection in the treatment of acute comitant esotropia (ACE) with different doses. Methods: This retrospective cohort study included data from patients with ACE who received BTA injection treatment at the First Affiliated Hospital of Zhengzhou University from June 2019 to June 2022. All patients underwent routine ophthalmic examinations, including best-corrected visual acuity (BCVA), spherical equivalent (SE), as well as specialized examinations for strabismus, including the degree of esotropia, eye movement status, and binocular visual function. Patients were categorized into small esotropia [≤60 prism diopters (PD)] and large esotropia (>60 PD) groups based on the pre-treatment degree of esotropia. Each group was further divided into 2.5 U and 5.0 U dose subgroups. Monocular injections were administered to the non-dominant eye. The esotropia degree was recorded and compared at 1, 2, 3, and 6 months of follow-up. The proportion of effectively treated patients in each group was documented. The number of cases with various levels of visual functions (including simultaneous vision, near stereopsis, and distance stereopsis) at 6 months post-treatment was compared, and complications during the follow-up period were observed. Statistical analyses were conducted using t-tests, Mann-Whitney U tests, and χ2 tests. Results: A total of 70 patients were included in the study, comprising 46 males and 24 females, with a median age of 5.0 (4.0, 8.3) years. Among them, 37 patients had small esotropia, with 25 in the 2.5 U group and 12 in the 5.0 U group. Thirty-three patients had large esotropia, with 18 in the 2.5 U group and 15 in the 5.0 U group. There were no statistically significant differences in baseline data, including age, duration of the condition, pre-treatment esotropia degree, BCVA and SE, between the two dose groups in both small and large esotropia patients (all P>0.05). In small esotropia patients, at 1 and 2 months post-treatment, the esotropia degree in the 5.0 U group was -20.00 (-37.50, -7.00) and 0.00 (0.00, 0.00) PD, respectively, which was significantly lower than the 0.00 (-10.00, 4.50) and 5.00 (0.00, 6.50) PD in the 2.5 U group (all P<0.05). At 3 and 6 months post-treatment, the esotropia degree in the 2.5 U group was 5.00 (0.00, 15.00) and 2.00 (0.00, 6.00) PD, respectively, while in the 5.0 U group, it was 0.00 (0.00, 4.50) and 0.00 (0.00, 3.75) PD, with no statistically significant differences between the two groups (all P>0.05). In the 2.5 U group, 20 cases were effectively treated, accounting for 80.0%, while in the 5.0 U group, 10 cases were effective, accounting for 10/12, with no significant difference between the two groups (P>0.05). In the 2.5 U group and the 5.0 U group, the proportions of cases with various levels of visual functions were as follows: simultaneous vision, 76.0% (19/25) and 10/12; near stereopsis, 48.0% (12/25) and 7/12; distance stereopsis, 44.0% (11/25) and 7/12, respectively. No statistically significant differences were observed in these proportions (all P>0.05). In patients with large esotropia, the esotropia degrees in the 5.0 U group at various follow-up times were -5.00 (-25.00, 5.00), 0.00 (0.00, 7.00), 2.00 (0.00, 10.00), and 5.00 (0.00, 7.00) PD, respectively. For the 2.5 U group, the corresponding values were 5.00 (2.75, 27.75), 10.00 (3.75, 24.75), 12.00 (3.75, 38.75), and 14.00 (3.50, 54.00) PD, respectively. The esotropia degrees in the 5.0 U group were consistently lower than those in the 2.5 U group (all P<0.05). The proportion of effective treatment in the 5.0 U group (13/15) was higher than that in the 2.5 U group (9/18), and the proportion of cases with distance stereopsis in the 5.0 U group (9/15) was higher than that in the 2.5 U group (4/18), both showing statistically significant differences (all P<0.05). The number of cases with simultaneous vision and near stereopsis showed no significant differences between the two groups (all P>0.05). The proportion of complications in the 2.5 U and 5.0 U groups in both large and small esotropia patients was 9/18, 13/15, 80.0% (20/25), and 10/12, respectively, with no statistically significant differences (all P>0.05). All complications spontaneously resolved within 3 months post-treatment. Conclusions: BTA injection is effective in the treatment of ACE, and for ACE patients with esotropia degrees greater than 60 PD, increasing the injection dose to 5.0 U can achieve better therapeutic outcomes.

[Current situation and trend of medical laboratory results homogeneity management]

Medical test results are indispensable and important tools in diagnosis and treatment services. It is necessary to promote the homogenization of test results first, because homogenization is the basis for mutual recognition of test results. Mutual recognition of medical test results can help share resources among medical institutions, provide more reliable test results for early prevention, screening and treatment of diseases, and reduce repeated tests, thus improving people's medical experience. In recent years, with the deepening of medical system reform and the promotion of graded diagnosis and treatment, governments have continuously introduced policies of mutual recognition of test results around country. However, homogenization is a prerequisite for mutual recognition of test results, with the emergence of intelligent medicine in the era of internet big data, opportunities and challenges coexist in the development of homogeneity management. In the future, the homogeneity of medical test results will present a trend of digitalization, automation, informatization and intelligence.

[Application of Mdr2 gene knockout mice in liver disease research]

Mdr2 knockout mice is a liver disease model, which causes cholestasis due to the lack of phospholipids in the bile. At present, it is not only used for the study of human homologous MDR3 gene, but also widely used as an animal model of liver diseases such as primary sclerosing cholangitis, liver fibrosis, progressive familial intrahepatic cholestasis, liver cancer. Herein, we review the Mdr2 knockout mice physiological characteristics and its application in liver disease research.

Association of improved overall survival with decreased distant metastasis following asparaginase-based chemotherapy and radiotherapy for intermediate- and high-risk early-stage extranodal nasal-type NK/T-cell lymphoma: a CLCG study

BACKGROUND

This study evaluated the survival benefit of asparaginase (ASP)-based versus non-ASP-based chemotherapy combined with radiotherapy in a real-world cohort of patients with early-stage extranodal nasal-type natural killer/T-cell lymphoma (ENKTCL).

PATIENTS AND METHODS

We identified 376 patients who received combined radiotherapy with either ASP-based (ASP, platinum, and gemcitabine; n = 286) or non-ASP-based (platinum and gemcitabine; n = 90) regimens. The patients were stratified into low-, intermediate-, and high-risk groups using the early stage-adjusted nomogram-revised risk index. Overall survival (OS) and distant metastasis (DM)-free survival (DMFS) between the chemotherapy regimens were compared using inverse probability of treatment weighting (IPTW) and multivariable analyses.

RESULTS

ASP-based (versus non-ASP-based) regimens significantly improved 5-year OS (84.5% versus 73.2%, P = 0.021) and DMFS (84.4% versus 74.5%, P = 0.014) for intermediate- and high-risk patients, but not for low-risk patients in the setting of radiotherapy. Moreover, ASP-based regimens decreased DM, with a 5-year cumulative DM rate of 14.9% for ASP-based regimens compared with 25.1% (P = 0.014) for non-ASP-based regimens. The survival benefit of ASP-based chemotherapy and radiotherapy remained consistent after adjusting the confounding variables using IPTW and multivariate analyses; additional sensitivity analyses confirmed these results.

CONCLUSIONS

The findings provided support for ASP-based chemotherapy and radiotherapy as a first-line treatment strategy for intermediate- and high-risk early-stage ENKTCL.

Giant isotropic magneto-thermal conductivity of metallic spin liquid candidate Pr2Ir2O7 with quantum criticality

Spin liquids are exotic states with no spontaneous symmetry breaking down to zero-temperature because of the highly entangled and fluctuating spins in frustrated systems. Exotic excitations like magnetic monopoles, visons, and photons may emerge from quantum spin ice states, a special kind of spin liquids in pyrochlore lattices. These materials usually are insulators, with an exception of the pyrochlore iridate Pr2Ir2O7, which was proposed as a metallic spin liquid located at a zero-field quantum critical point. Here we report the ultralow-temperature thermal conductivity measurements on Pr2Ir2O7. The Wiedemann-Franz law is verified at high fields and inferred at zero field, suggesting no breakdown of Landau quasiparticles at the quantum critical point, and the absence of mobile fermionic excitations. This result puts strong constraints on the description of the quantum criticality in Pr2Ir2O7. Unexpectedly, although the specific heats are anisotropic with respect to magnetic field directions, the thermal conductivities display the giant but isotropic response. This indicates that quadrupolar interactions and quantum fluctuations are important, which will help determine the true ground state of this material.

Barriers to early diagnosis and treatment of severely immunosuppressed patients with HIV-1 infection: A quantitative and qualitative study

OBJECTIVES

To explore the barriers to early diagnosis of HIV infection and timely initiation of antiretroviral therapy (ART).

METHODS

We assessed the annual number and proportion of ART-naïve people living with HIV infection (PLWH) with severe immunosuppression in Shenzhen, China, from 2008 to 2019. Selected ART-naïve PLWHs with severe immunosuppression who were seeking treatment for the first time in the hospital in 2019 were subjected to an in-depth interview.

RESULTS

The proportion of severely immunosuppressed, ART-naïve PLWH decreased from 36.73% in 2008 to 8.94% in 2015, and then plateaued at approximately 10% from 2015 to 2019. Overall, 55 patients, 70% of whom were men who had sex with men, participated in the qualitative interviews. Ten of them delayed treatment after diagnosis, with a median [interquartile range (IQR)] interval of 5.83 (3.98-8.54) years between diagnosis and ART. More than 80% of the patients reported casual sexual contact within a median period of 6 years and with a median (IQR) of nine (4-20) casual sex partners. The major barriers to HIV testing and diagnosis included lack of knowledge about HIV and high-risk behaviours, low awareness about HIV testing, and resistance to HIV testing. The major barriers to ART initiation included lack of knowledge about the importance of ART and change of national ART eligibility policy, and HIV-related stress.

CONCLUSIONS

The number of PLWHs with severe immunosuppression who seek treatment remains high in Shenzhen, China. Thus, current HIV-related care programmes targeting access to early diagnosis and treatment need to be improved.

Protection of forensic scene investigation and postmortem examination during the epidemic period of COVID-19

Abstract

[Research progress of cirrhosis with portal vein thrombosis]

Portal vein thrombosis refers to the formation of a thrombus in the trunk of the portal vein and /or its branches due to various causes, and is one of the common complications of cirrhosis. Synthesizing the existing evidence, this paper summaries the cirrhosis with portal vein thrombosis in terms of epidemiology, etiology, pathophysiology, risk factors, definition and classification, clinical manifestations and complications, diagnosis and screening, treatment, follow-up and prognosis, prospects and problems.

[Prognostic evaluation of nutritional indicators in patients with limited-stage small cell lung cancer]

Objective: To explore the effect of nutritional status pre-and during chemoradiotherapy on the prognosis of patients with limited- stage small cell lung cancer (LS-SCLC). Methods: We retrospectively collected medical records of 172 LS-SCLC patients undergoing concurrent chemoradiotherapy in our hospital from 2000 to 2014, with 126 males and 46 females. The data of complete blood count and hepatic and renal function were collected before initial treatment, before radiotherapy, 4 weeks during radiotherapy, and 1 month after complete of treatment. The prognostic nutritional index(PNI)was calculated. Kaplan-Meier method was used to calculate the survival rate. Log-rank test was performed used to compare the survival differences between groups. Multivariate prognostic analysis was performed using Cox regression model. Results: The median overall survival (OS) was 21 months, with median progression-free survival (PFS) of 11 months. At the beginning of treatment, patients with pre-treatment PNI ≥ 53 had significantly superior OS (median 37 vs 15 months, P=0.001) and PFS (median 16 vs 10 months, P=0.017). Patients with pre-treatment hemoglobin ≥140 g/L and <140 g/L had an median OS of 32 months and 17 months (P=0.019), and median PFS of 16 months and 9 months (P=0.040), respectively. During chemoradiation, patients with elevated hemoglobin had similar median OS compared with those had decreased hemoglobin (27 vs 18 months, P=0.063, but superior median PFS (15 vs 9 months, P=0.017). Multivariate analysis revealed that prophylactic cranial irradiation, pre-treatment hemoglobin ≥140 g/L, and pretreatment PNI ≥53 were independent predictors of OS and PFS in patients with LS-SCLC. Conclusion: Pre-treatment nutritional status and the changes of nutritional status during chemoradiotherapy is significantly associated with the prognosis of patients with limited-stage small cell lung cancer. The patients with better pre-treatment nutritional status have a better prognosis.

[Study on anti- fibrotic mechanism of Fuzheng -Huayu formula to suppress autophagy in mice]

Objective: To determine whether the anti-hepatic fibrosis effect of Fuzheng-Huayu formula is related to suppress autophagy in mice. Methods: C57 mice were randomly divided into normal group (N group) and model group. The model group was induced by intraperitoneal injection of carbon tetrachloride to induce liver fibrosis in mice, and the normal group was injected with equal volume of olive oil. After 1 week, the model group was randomly divided into model (M) group, rapamycin (Rapa) group, rapamycin plus chloroquine (Rapa+CQ) group, rapamycin plus salvianolic acid B (Rapa+Sal B) group, rapamycin plus Fuzheng -Huayu formula (Rapa+FZ) group. Each drug group was administered corresponding drugs by gavage on a daily basis, and N group and M group were given the equal amount of drinking water by gavage. After 5 weeks, the mice were sacrificed, and HE and Sirius red staining were used to observe the inflammation and collagen deposition on liver tissue in each group. The hydroxyproline content was determined by alkaline hydrolysis method. Western blotting was used to detect changes in the expression of autophagy in liver tissue and microtubule-associated protein 1 light chain 3II/I (LC3II/I), p62, α-smooth muscle actin (ɑ-SMA) and type I collagen expression. Immunofluorescence staining was used to observe the immunofluorescence localization of ɑ-SMA and LC3B in liver tissues of each group. ). A t-test was used to compare the two independent samples. LSD or Dunnett's T3 test were used to compare the mean of multiple samples. Results: There was no significant difference in N and M groups in terms of body weight. The body weight of the mice in each drug group decreased significantly (F = 14.041, P < 0.001). The liver/spleen /body weight ratios of each drug group and M group were significantly higher than the N group (F = 26.992, 6.589, P < 0.001). The expression of p62 protein in the liver tissue of mice in each drug group was lower than M group, and the difference between Rapa group and Rapa+Sal B group (F = 3.085, P = 0.039, 0.003) was statistically significant, while that of Rapa + Sal B group was lower. Compared with group M, the expression of LC3B II in Rapa group was significantly higher (F = 7.514, P = 0.01). Immunofluorescence staining showed that LC3B and α-SMA CO-stained cells were absent in the liver of mice in N group, and co-stained cells were found in the liver of mice in M group. The co-stained cells in the liver of mice in each drug group were significantly higher than M group, and the co-stained cells in Rapa+FZ group were fewer. Compared with the N group, the collagen deposition of M group and each drug group was significantly increased; the collagen deposition of each drug group was lower than that of the M group. There was no statistically significant difference between each drug group. Compared with N group (77.75 + 48.79), hydroxyproline in liver tissue of mice in M group was significantly increased (293.48 + 84.43) (F = 3.015, P = 0.005), and the content of hydroxyproline in liver tissue of mice in each drug group was lower than M group, but the difference was not statistically significant (F = 0.750, P = 0.573). Compared with the N group, the expressions of α-SMA and type I collagen in the M group were significantly increased (F = 27.718, 18.893, P < 0.01). The expression of α-SMA in Rapa group and Rapa+Sal B group was similar to M group, while Rapa + CQ group and Rapa + FZ group were significantly lower than Rapa group and M group (P < 0.01). The expression of type I collagen in Rapa + CQ group was significantly higher than Rapa group (P = 0.017), while the expression of type I collagen in Rapa + FZ group was significantly lower than M group (P = 0.013). Conclusion: Autophagy of hepatic stellate cells was observed in carbon tetrachloride-induced liver fibrosis model. Rapamycin can promote autophagy in hepatocytes and hepatic stellate cells. Fuzheng-Huayu formula and Salvianolic Acid B might antagonize the effect of rapamycin on autophagy.

[Endoscopicretrograde cholangio-pancreatography management of long-term complications after pancreaticoduodenectomy]

Objective: To investigate the feasibility and effectiveness of endoscopicretrograde cholangio-pancreatography(ERCP)in the management of long-term complications after pancreaticoduodenectomy. Methods: From January 2009 to July 2018, the clinical data of 62 patients with biliary or pancreatic long-term complications after pancreatoduodenectomy were reviewed at Department of General Surgery, and the corresponding ERCP were carried out in the multi-disciplinary cooperation.There were 39 males and 24 females.The age was 56.5 years(aging from 13 to 76 years). The time of treatment was 3 months to 20 years after pancreatoduodenectomy.The long-term biliopancreatic complications after pancreatoduodenectomy included 51 cases of biliary calculi, 42 cases of bilioenteric anastomotic stenosis with proximal bile duct dilatation, and 11 cases of pancreaticointestinal anastomosis stenosis with distal pancreatic duct dilatation.All patients received conventional duodenoscopy or single-balloon enteroscopy assisted ERCP under general anesthesia. Results: A total of 95 ERCP were performed in 62 patients, averaging 1.5 times per case.The long-term complications of cholangiopancreatic after pancreatoduodenectomy(ERCP indications) included 56 times of bile duct stones(58.9%), 45 times of bilioenteric anastomatic stricture(47.4%), 11 times of recurrent pancreatitis(11.6%), 6 cases(6.3%) of bilioenteric anastomatic foreign body, 3 times of intrahepatic bile duct stenosis(3.2%). Among the 95 times, 82 times(86.3%) achieved endoscopic endoscopy, 76 times(80.0%) were diagnosed successfully, and 72 times(75.8%) were successfully treated with ERCP.Small intestinal perforation occurred in 1 patient undergoing duodenoscopy, and then healed by surgical repair. Conclusion: Multi-disciplinary collaboration of ERCP is safe and effective in the treatment of long-term complications after pancreaticoduodenectomy, but the long-term effect still needs further clinical follow-up.

[Anti-fibrosis of liver, Shouder heavy responsibilities]

In recent years, many studies have been conducted on liver fibrosis. This article introduces the latest advances in the pathogenesis, diagnosis, and treatment of liver fibrosis. There is still a long way to go for the research on anti-fibrosis therapy, and this difficult problem will finally be solved with the help of further studies.

[Value of a two-step approach with cytokeratin-18 and controlled attenuation parameter in noninvasive differential diagnosis of nonalcoholic steatohepatitis]

OBJECTIVE

To investigate the value of a two-step approach with cytokeratin-18 (CK-18) and controlled attenuation parameter (CAP) in the noninvasive diagnosis of nonalcoholic steatohepatitis (NASH).

METHODS

A total of 65 patients with biopsy-proven nonalcoholic fatty liver disease were enrolled, including 30 patients with NASH. The M30 and M65 enzyme-linked immunosorbent assay kits were used to measure serum CK-18, and FibroScan was used to measure CAP. The receiver operating characteristic (ROC) curve was plotted, and the area under the ROC curve (AUROC) was used to determine the value of noninvasive diagnosis. The binary logistic regression model was used to calculate the predicted probability of combined diagnosis. The maximum Youden index, a sensitivity of >90%, and a specificity of > 90% were used to determine the optimal cut-off value, the low value, and the high value, respectively.

RESULTS

The results of the multivariate analysis showed that M65 (OR = 1.004, 95% CI 1.002-1.007, P = 0.003) and CAP (OR = 1.017, 95% CI 1.001-1.033, P = 0.036) were independent predictors of NASH. The AUROC of M65+CAP was 0.851 (95% CI 0.761-0.942), higher than 0.808 (95% CI 0.702-0.913) of M65 and 0.677 (95% CI 0.545-0.808) of CAP alone. A two-step approach with high (820.8 U/L) and low (527.7 U/L) values for M65 and the optimal cut-off value (293.5 dB/m) for CAP was used for the differential diagnosis of NASH, with a positive predictive value of 85.7%, a negative predictive value of 100%, and a coincidence rate of 92.0%.

CONCLUSION

A two-step approach with M65 and CAP can improve the value of noninvasive diagnosis of NASH, and a high negative predictive value can avoid unnecessary liver biopsy.

Positive association between PPARD rs2016520 polymorphism and coronary heart disease in a Han Chinese population

PPARD encodes peroxisome proliferator-activated re-ceptor delta, which has been shown to play an important role in control-ling lipid metabolism and atherosclerosis. In this case-control study, we explored the relationship between PPARD rs2016520 polymorphism and coronary heart disease (CHD) in a Han Chinese population. A to-tal of 657 CHD cases and 640 controls were included in the associa-tion study. rs2016520 polymorphism genotyping was performed using the melting temperature-shift polymerase chain reaction method. The PPARD rs2016520-G allele reduced CHD risk by 17.9% (χ(2) = 5.061, P = 0.025, OR = 0.821, 95%CI = 0.692-0.975). Furthermore, a signifi-cant difference in CHD risk was observed for the PPARD rs2016520 polymorphism in the dominant model (AG + GG vs AA: χ(2) = 4.751, degrees of freedom (df) = 1, P = 0.029, OR = 0.784, 95%CI = 0.631- 0.976). Analysis by age suggested that the G-allele decreased CHD risk by 14.8% in ages greater than 65 years (χ(2) = 4.446, P = 0.035, OR = 0.852, 95%CI = 0.684-1.060). In contrast, meta-analysis of PPARD rs2016520 among 3732 cases and 5042 controls revealed no associa-tion between PPARD rs2016520 and CHD (P = 0.19). We found that the PPARD rs2016520-GG genotype decreased CHD risk in a Han Chinese population. Moreover, we found an association between serum high-density lipoprotein cholesterol level and PPARD rs2016520 in senior individuals aged ≥ 65 years. The meta-analysis revealed no association between PPARD rs2016520 and CHD, suggesting ethnic differences in the association between the PPARD locus and CHD.

Therapeutic mechanism of treating SMMC-7721 liver cancer cells with magnetic fluid hyperthermia using Fe₂O₃ nanoparticles

This study aimed to investigate the therapeutic mechanism of treating SMMC-7721 liver cancer cells with magnetic fluid hyperthermia (MFH) using Fe₂O₃ nanoparticles. Hepatocarcinoma SMMC-7721 cells cultured in vitro were treated with ferrofluid containing Fe₂O₃ nanoparticles and irradiated with an alternating radio frequency magnetic field. The influence of the treatment on the cells was examined by inverted microscopy, MTT and flow cytometry. To study the therapeutic mechanism of the Fe₂O₃ MFH, Hsp70, Bax, Bcl-2 and p53 were detected by immunocytochemistry and reverse transcription polymerase chain reaction (RT-PCR). It was shown that Fe₂O₃ MFH could cause cellular necrosis, induce cellular apoptosis, and significantly inhibit cellular growth, all of which appeared to be dependent on the concentration of the Fe₂O₃ nanoparticles. Immunocytochemistry results showed that MFH could induce high expression of Hsp70 and Bax, decrease the expression of mutant p53, and had little effect on Bcl-2. RT-PCR indicated that Hsp70 expression was high in the early stage of MFH (<24 h) and became low or absent after 24 h of MFH treatment. It can be concluded that Fe₂O₃ MFH significantly inhibited the proliferation of in vitro cultured liver cancer cells (SMMC-7721), induced cell apoptosis and arrested the cell cycle at the G₂/M phase. Fe₂O₃ MFH can induce high Hsp70 expression at an early stage, enhance the expression of Bax, and decrease the expression of mutant p53, which promotes the apoptosis of tumor cells.

Prevalence of helminthes in adult dogs in Heilongjiang Province, the People’s Republic of China

The prevalence of helminthes in adult dogs was investigated in Heilongjiang Province, the People's Republic of China, between 1996 and 2004. A total of 178 adult farm dogs from representative geographical locations in Heilongjiang Province were killed and examined for the presence of helminthes using a helminthological approach. The worms were examined, counted, and identified to species according to existing keys and descriptions. A total of 17 species of helminthes were found to infect dogs, and they represented two phyla, three orders, 13 families, and 15 genera. All dogs were infected by more than one helminth species. Clonorchis sinensis (26.4%), Paragonimus westermani (7.9%), and Metagonimus yokogawai (6.2%) were the most common trematode species; Mesocestoides lineatus (20.2%), Taenia hydatigena (19.7%), and Dipylidium caninum (14.6%) were the most common cestodes species; and Ancylostoma caninum (66.3%), Toxocara canis (36.5%), and Trichinella nativa (21.9%) were the most common nematode species. The results of the present investigation provide relevant "base-line" data for assessing the effectiveness of future control strategies against helminth infection in dogs in Heilongjiang Province, China.

A comparison of ischemic preconditioning versus terminal warm cardioplegia with controlled reperfusion in open heart operation

BACKGROUND

The purpose of this study was to evaluate the effects of three different methods of cardioprotection in patients undergoing valve replacement.

METHODS

Ninety patients undergoing elective valve replacement were randomly divided into three groups. In group 1 (n=30), the patients received intermittent cold blood cardioplegia. In group 2 (n=30) they received terminal warm cardioplegia and controlled reperfusion, and in group 3 (n=30), the patients received two cycles of ischemia (2 minutes) and reperfusion (3 minutes) before heart arrest induced by cold blood cardioplegia. The parameters of cardiac function, creatine kinase MB, and clinical outcomes were recorded to assess the effects of experiment.

RESULTS

The major preoperative and intraoperative variables are comparable within the three groups. The number of patients requiring the support of inotropic agents was 70% (21/30), 33% (11/30) and 40% (12/30) in group 1, 2 and 3, respectively (p<0.05). The doses of inotropic agent in groups 2 and 3, were significantly lower than in group 1 (1.5+/-0.3 and 1.8+/-0.4 versus 4.5+/-0.8 microg x kg x min(-1), p<0.01) during the first 24 hours after operation. Two deaths (30 day-hospital mortality) occurred, one in group 1 and one in group 2. The cardiac index at 2 hours after bypass discontinuing were 2.2+/-0.04, 3.0+/-0.1 and 2.8+/-0.05 L/m(2) in group 1, 2 and 3, respectively (p<0.01). The left ventricular stroke work index were 24.8+/-1.3, 34.5+/-1.6 and 31.6+/-1.2 g/m x m(2) in group 1, 2, 3, respectively (p<0.01). The release of CK-MB in group 2 and 3 were lower than in group 1 (68+/-7, 81+/-9 versus 116+/-10 IU/L, p<0.01).

CONCLUSIONS

Terminal warm cardioplegia with controlled aortic root reperfusion and ischemic preconditioning equally improve cardiac function and reduce the requirement of inotropic agents in patients undergoing valve replacement.

Effects of salvianolic acid-A on rat hepatic stellate cell proliferation and collagen production in culture

AIM

To investigate the effects of salvionolic acid-A (SA-A), one of main effective components of Salvia miltiorrhiza for its antifibrotic action, on the cell proliferation and collagen production in cultured hepatic stellate cells (HSC).

METHODS

HSC were isolated through in situ perfusion of liver with pronase E and collagenase, and gradient centrifugation with Nycodenz. The cultured HSC were incubated with SA-A 0.1-100 mumol/L for 24 h. MTT spectrometric assay and intercellular incorporation of methyl-[3H]thymidine ([3H]TdR) was used to assess the cell proliferation. The amount of collagen was semi-quantified by ponceau staining and image analysis, the amount of type I collagen secretion was measured with ELISA and normalized by the total protein of cell layer. The total RNA was prepared from the control cells and the drug treated cells respectively, and the expression of pro-collagen alpha 2 (I) mRNA was semi-quantitatively analyzed with RT-PCR.

RESULTS

SA-A 100 mumol/L showed a little cytotoxity, SA-A 0.1-10 mumol/L did not influence cell morphology, and SA-A 1-100 mumol/L decreased the cell proliferation significantly in a concentration-dependent manner (P < 0.05). SA-A 1, 10, 100 mumol/L decreased the cell collagen deposition by 78.6%, 71.8%, and 61.3% of the control respectively (P < 0.05), and decreased type I collagen secretion to 53.1%, 52.6%, and 49.5% (P < 0.01 or P < 0.05). Both SA-A 1 and 10 mumol/L downregulated procollagen alpha 2 (I) mRNA expression remarkably (P < 0.05).

CONCLUSION

SA-A inhibited HSC proliferation and collagen expression. The inhibitory effect on HSC activation is the main mechanism of SA-A action against liver fibrosis.

Wortmannin, a PI3-kinase inhibitor: promoting effect on insulin secretion from pancreatic beta cells through a cAMP-dependent pathway

To determine the role of phosphatidylinositol 3-kinase (PI3-kinase) in the regulation of insulin secretion, we examined the effect of wortmannin, a PI3-kinase inhibitor, on insulin secretion using the isolated perfused rat pancreas and freshly isolated islets. In the perfused pancreas, 10(-8) M wortmannin significantly enhanced the insulin secretion induced by the combination of 8.3 mM glucose and 10(-5) M forskolin. In isolated islets, cyclic AMP (cAMP) content was significantly increased by wortmannin in the presence of 3.3 mM, 8.3 mM, and 16.7 mM glucose with or without forskolin. In the presence of 16.7 mM glucose with or without forskolin, wortmannin promoted insulin secretion significantly. On the other hand, in the presence of 8.3 mM glucose with forskolin, wortmannin augmented insulin secretion significantly; although wortmannin tended to promote insulin secretion in the presence of glucose alone, it was not significant. To determine if wortmannin increases cAMP content by promoting cAMP production or by inhibiting cAMP reduction, we examined the effects of wortmannin on 10(-4) M 3-isobutyl-1-methylxantine (IBMX)-induced insulin secretion and cAMP content. In contrast to the effect on forskolin-induced secretion, wortmannin had no effect on IBMX-induced insulin secretion or cAMP content. Moreover, wortmannin had no effect on nonhydrolyzable cAMP analog-induced insulin secretion in the perfusion study. These data indicate that wortmannin induces insulin secretion by inhibiting phosphodiesterase to increase cAMP content, and suggest that PI3-kinase inhibits insulin secretion by activating phosphodiesterase to reduce cAMP content.

Preconditioning improves myocardial preservation in patients undergoing open heart operations

BACKGROUND

Our previous work has shown that preconditioning can promote the recovery of cardiac function in patients having an open heart procedure. Because preconditioning is regarded as the most powerful form of endogenous myocardial protection, we tested the hypothesis that preconditioning protects against myocardial ischemia-reperfusion injury in patients undergoing prolonged cold crystalloid cardioplegic arrest.

METHODS

Thirty patients who had rheumatic heart disease and required both aortic and mitral valve replacement were studied. Patients were randomly divided into two equal groups. Preconditioning was accomplished using two cycles of 2-minute occlusion of the vena cava and aorta followed by 3 minutes of reperfusion under cardiopulmonary bypass. All hearts were arrested with 4 degrees C St. Thomas' Hospital cardioplegic solution. Myocardial protective effects were assessed by changes in myocardial levels of adenosine triphosphate, electrocardiographic activity, leakage of myocardial enzymes, and myocardial contractility.

RESULTS

The adenosine triphosphate content in ischemic myocardium was higher in the preconditioning group than in the control group (p < 0.05 90 minutes after ischemia), and there was a significant reduction in release of the myocardial-specific isoenzyme of creatine kinase in the preconditioning group. Preconditioning improved the recovery of myocardial contractility (first derivative of left ventricular developed pressure, 1,490 +/- 102 mm Hg/s versus 1,250 +/- 97 mm Hg/s 30 minutes after reperfusion; p < 0.05), and there was also a protective effect on electrocardiographic activity.

CONCLUSIONS

Our results suggest that ischemic preconditioning protects the myocardium in humans from the severe ischemia-reperfusion injury produced after prolonged arrest with cold crystalloid cardioplegia.

[Actions of salvianolic acid A on CCl4-poisoned liver injury and fibrosis in rats]

AIM

To study the actions of salvianolic acid A (SA-A) on liver injury and liver fibrosis.

METHODS

The liver fibrotic rat was made by i.p. injection of CCl4. The model rats were divided into 3 groups treated with SA-A, colchicine (Col), and Salvia miltiorrhiza Bunge (SMB), respectively. Six wk later the rat liver pathology was examined, type I and III collagen in the liver were examined by immunohistochemistical method. Also hydroxyproline (Hyd) and malondialdehyde (MDA) in the liver, alanine aminotransferase (AlaAT), aspartate aminotransferase (AspAT), and albumin (Alb) levels in the serum were measured.

RESULTS

SA-A inhibited serum AlaAT and AspAT activities, decreased MDA and Hyd contents, alleviated liver fibrogenesis, protected deposition of type I and III collagen in liver matrix. The actions of SA-A on liver fibrosis were similar to those of Col and SMB, action of SA-A decreasing MDA was better than that of Col.

CONCLUSION

SA-A has marked effects against liver injury and fibrosis, associated with its anti-lipid peroxidation actions.

Bradyrhizobium liaoningense sp. nov., isolated from the root nodules of soybeans

Seventeen strains of extra-slowly growing (ESG) soybean rhizobia isolated from root nodules of Glycine soja and Glycine max growing in five provinces (Liaoning, Heilongjiang, Shanxi, Hubei, and Anhui) in the People's Republic of China were compared with 48 reference strains belonging to the genera Bradyrhizobium, Rhizobium, and Agrobacterium by performing a numerical analysis of 191 phenotypic features. Our results showed that all of the ESG strains examined clustered closely in the genus Bradyrhizobium but were separated from Bradyrhizobium japonicum at the species level and that they could be differentiated from Rhizobium and Agrobacterium species at the genus level. On the basis of the results of our numerical taxonomy analysis, a genomic DNA G & C content analysis, DNA-DNA hybridization experiments, a partial 16S rRNA sequence analysis, a serological analysis, an N and C content analysis, and an N/C ratio analysis of members of the three groups of soybean rhizobia, we propose the name Bradyrhizobium liaoningense sp. nov. for the ESG strains; the type strain of this species is strain 2281.

[Observation on the action of extractum semen Persicae on anti-fibrosis of liver]

It was observed that Extractum Semen Persicae acted obviously on hepatic fibrosis induced by CCl4. Through promoting the degradation of collagens type I, II, IV, VI and fibronectin, ESP has proved helpful in markedly reducing the fibrous septa composed of both collagenous and reticular fibers as well as in repairing the structure of hepatic tissues.

Effects of glutathione depletion using buthionine sulphoximine on the cytotoxicity in mammalian cells and human tumor cells in vitro

An inhibitor of glutathione biosynthesis, buthionine sulphoximine (BSO), was used to deplete the endogenous thiols in mammalian cells in vitro. In this study, the cytotoxicity of BSO and BSO combined with the hypoxic cell radiosensitizer misonidazole (MISO) was investigated. Both aerobic and hypoxic cytotoxicity of MISO was found to be increased. The concentration of BSO required to reduce the colony forming ability to 50% (Cc) for the chronic cytotoxicity on V79 cells was 0.03 mmol/L under aerobic condition, while the Cc for the acute cytotoxicity on V79 cells under hypoxic and aerobic conditions was 0.4 and 0.5 mmol/L. The growth inhibition rate of human tumor cells K562 and SGC-7901 by BSO was 6.89-26.06% and 12.01-55.69%, respectively. Enhanced cytotoxicity activity was observed when BSO was used in combination with cis-dichlorodiamino Pt(II) or 5-fluorouracil.

Daurisoline derivatives inhibit the ability of calmodulin to stimulate cyclic nucleotide phosphodiesterase activity

Daurisoline alkaloid derivatives were found to be potent calmodulin (CaM) antagonists. The ability of daurisoline derivatives to attenuate the stimulatory effect on calmodulin activated cyclic nucleotides phosphodiesterase (CaM-PDE) was studied. These compounds did not inhibit the basal activity of this enzyme. The hydrophobicity of these compounds was related to their inhibitory potency. It is suggested that such drugs bind directly to calmodulin in a Ca2(+)-dependent fashion, as indicated by their ability to change calmodulin fluorescence.