Serious Failure Modes After EVAR Are Device Specific

OBJECTIVES

Type I and III endoleaks following endovascular aneurysm repair (EVAR) can lead to catastrophic events that require major re-interventions. We reviewed our experience with aortic endograft re-interventions for type I and III endoleaks and other serious failures among different devices.

METHODS

We retrospectively reviewed patients with a prior EVAR who underwent open conversion (OC) or major endovascular intervention (MEI) (re-lining, cuff/limb extension, parallel graft) for type I/III endoleaks at our institution from 2002 to 2019. Baseline characteristics, procedural details, re-interventions, and outcomes were collected.

RESULTS

A total of 229 patients (194 men) underwent re-interventions for type I and III endoleaks after EVAR (90 OC, 139 MEI) for devices implanted between 1997 and 2019. Average age at re-intervention was 78±8.5 years. A total of 135 (59%) were implanted at our institution, whereas 93 (41%) were referred. Median time to re-intervention was 4 years with 25% to 75% interquartile range (IQR) of 2.2-6.6 years. There was no significant difference in baseline demographics or type of re-interventions (OC/MEI) between device types. 42/229 (18%) presented with ruptured aneurysms, 20/229 (9%) were symptomatic, whereas the rest presented with asymptomatic radiographic findings. Type 1A endoleak was present in 146/229 (63.8%-72 with proximal migration), type IB in 46/229 (20.1%), type IIIA in 37/229 (16.6%), type IIIB in 15/229 (6.5%), and persistent aneurysm sac growth with no radiographic evidence of an endoleak in 6/229 (2.6%). Devices included most commercial products: AFX, Excluder, AneuRx, Ancure, Endurant, and Zenith. A smaller number of investigational devices accounted for the rest. Type 1A endoleak was the most common indication for re-intervention among all devices except for AFX and ancure devices, proximal migration was a frequent presentation with AneuRx. AFX devices more frequently presented with a type III and ancure devices more frequently presented with a type IB endoleak.

CONCLUSIONS

Serious failure modes after EVAR differ between endografts and occur throughout the follow-up period. This is important to guide targeted interrogation of surveillance studies and follow-up schedules, even for discontinued devices, as well as comparisons between various series and estimation of EVAR failure rates.

CLINICAL IMPACT

Surveillance after EVAR is critical for long term success of the repair, understanding of the differential modes of failure of every graft available is important in the longitudinal evaluation of these endografts. Equally important is the understanding of the modes of failure of legacy endografts that are no longer on the market but still being followed, in order to be able to tailor a surveillance regiemn and the evntual repair if needed.

Clustering of gout-related comorbidities and their relationship with gout flares: a data-driven cluster analysis of eight comorbidities

OBJECTIVES

To study the aggregation of multiple comorbidities in people with gout and explore differences in prognosis of gout flares among different subgroups.

METHODS

Hierarchical clustering was performed to identify homogeneous subgroups among 2639 people with gout using eight comorbidities. A one-year follow-up of acute gout flares in 463 of these people was conducted; the incidence and the timing of gout flares in each cluster were assessed to explore prognosis of gout flares. Binary logistic regression was applied to assess factors associated with gout flares.

RESULTS

In baseline study, we identified five subgroups (C1-C5). C1 (n = 671, 25%) was characterized by isolated gout with few comorbidities. C2 (n = 258, 10%) were all obese. Almost all people in C3 (n = 335, 13%) had diabetes (99.7%). All people in C4 (n = 938, 36%) had dyslipidemia. C5 (n = 437, 17%) had the highest proportion of cardiovascular disease (CVD, 53%), chronic kidney disease (CKD, 56%), and cancer (7%). In follow-up study, C5 had the highest incidence (71.9%) and earliest onset (median 3 months) of gout flares. C2 had the lowest incidence (52.1%) and the latest onset (median 10 months) of gout flares. The highest relative risk for gout recurrent was seen for C5 (OR = 2.09). Other factors associated with the risk of gout flares were age at diagnosis of gout, duration of gout, presence of tophi, and smoking ≥ 20 cigarettes/day.

CONCLUSIONS

We clustered people with gout into five groups with varying comorbidities. People with CVD, CKD, and cancer had the highest risk of gout flares and should receive comprehensive care.

Clinical Significance of Serum Iron Metabolism-Related Markers in Patients with Nasopharyngeal Carcinoma

INTRODUCTION

It is known that iron metabolism is dysregulated in nasopharyngeal carcinoma (NPC). However, a meaningful assessment of the iron metabolic status in cancer patient is still under debate. This study aims to evaluate the status of iron metabolism, as well as to explore the correlation between those related serum markers and clinicopathological features of patients with NPC.

METHODS

Peripheral blood was collected from 191 pretreatment NPC patients and 191 healthy controls. The red blood cell parameters, plasma Epstein-Barr virus (EBV) DNA load, serum iron (SI), total iron-binding capacity (TIBC), transferrin, soluble transferrin receptor (sTFR), ferritin, and hepcidin were quantitatively detected.

RESULTS

The mean levels of hemoglobin and red blood cell count in the NPC group were significantly lower than those in the control group, while no statistical differences in mean MCV were found between the two groups. Median levels of SI, TIBC, transferrin, and hepcidin were significantly lower in the NPC group than in the control group. Compared to patients with the T1-T2 classification, patients with the T3-T4 classification exhibited significantly lower expression levels of SI and TIBC. Serum levels of ferritin and sTFR were significantly higher in patients with M1 classification than those with M0 classification. The EBV DNA load was associated with serum levels of sTFR and hepcidin.

CONCLUSION

NPC patients had functional iron deficiency. The degree of iron deficiency was related to the tumor burden and metastasis of NPC. EBV might be involved in the regulation of iron metabolism in the host.

Identification of potential diagnostic and prognostic biomarkers for papillary thyroid microcarcinoma (PTMC) based on TMT-labeled LC-MS/MS and machine learning

OBJECTIVES

To explore the molecular mechanisms underlying aggressive progression of papillary thyroid microcarcinoma and identify potential biomarkers.

METHODS

Samples were collected and sequenced using tandem mass tag-labeled liquid chromatography-tandem mass spectrometry. Differentially expressed proteins (DEPs) were identified and further analyzed using Mfuzz and protein-protein interaction analysis (PPI). Parallel reaction monitoring (PRM) and immunohistochemistry (IHC) were performed to validate the DEPs.

RESULTS

Five thousand, two hundred and three DEPs were identified and quantified from the tumor/normal comparison group or the N1/N0 comparison group. Mfuzz analysis showed that clusters of DEPs were enriched according to progressive status, followed by normal tissue, tumors without lymphatic metastases, and tumors with lymphatic metastases. Analysis of PPI revealed that DEPs interacted with and were enriched in the following metabolic pathways: apoptosis, tricarboxylic acid cycle, PI3K-Akt pathway, cholesterol metabolism, pyruvate metabolism, and thyroid hormone synthesis. In addition, 18 of the 20 target proteins were successfully validated with PRM and IHC in another 20 paired validation samples. Based on machine learning, the five proteins that showed the best performance in discriminating between tumor and normal nodules were PDLIM4, ANXA1, PKM, NPC2, and LMNA. FN1 performed well in discriminating between patients with lymph node metastases (N1) and N0 with an AUC of 0.690. Finally, five validated DEPs showed a potential prognostic role after examining The Cancer Genome Atlas database: FN1, IDH2, VDAC1, FABP4, and TG. Accordingly, a nomogram was constructed whose concordance index was 0.685 (confidence interval: 0.645-0.726).

CONCLUSIONS

PDLIM4, ANXA1, PKM, NPC2, LMNA, and FN1 are potential diagnostic biomarkers. The five-protein nomogram could be a prognostic biomarker.

Thyroid surgery during coronavirus-19 pandemic phases I, II and III: lessons learned in China, South Korea, Iran and Italy

OBJECTIVE

We compared demographic and clinic-pathological variables related to the number of surgeries for thyroid conditions or for cancer, morbidity, and fine needle aspiration (FNA) practices among Covid19 pandemic phases I, II, III and the same seasonal periods in 2019.

METHODS

The prospective database of the Division of Thyroid Surgery, China-Japan Union Hospital of Jilin University, Changchun, China was used for this study. Covid19 emergency levels were stratified according to the World Health Organization: phase I (January 25-February 25, 2020), phase II (February 26-March 19), phase III (March 20-April 20).

RESULTS

There were fewer outpatient FNAs and surgeries in 2020 than in 2019. There were no thyroid surgeries during phase I. There were also fewer surgeries for cancer with a significant reduction of advanced stage cancer treatments, mainly stage T1b N1a in phase II and T3bN1b in phase III. Operative times and postoperative stays were significantly shorter during the pandemic compared to our institutional baseline. In phase III, vocal cord paralysis (VCP) increased to 4.3% of our baseline numbers (P = 0.001). There were no cases of Covid19-related complications during the perioperative period. No patients required re-admission to the hospital.

CONCLUSION

The Covid19 outbreak reduced thyroid surgery patient volumes. The decrease of Covid19 emergency plans contributed to unexpected outcomes (reduction of early stage cancer treatment, decreased operative times and hospital stays, increased VCP rate).

Zhuyu Annao decoction promotes angiogenesis in mice with cerebral hemorrhage by inhibiting the activity of PHD3

Some traditional Chinese decoctions, such as Zhuyu Annao, exert favorable therapeutic effects on acute cerebral hemorrhage, hemorrhagic stroke, and other neurological diseases, but the underlying mechanism remains unclear. This study aimed to determine whether Zhuyu Annao decoction (ZYAND) protects the injured brain by promoting angiogenesis following intracerebral hemorrhage (ICH) and elucidate its specific mechanism. The effect of ZYAND on the nervous system of mice after ICH was explored through behavioral experiments, such as the Morris water maze and Rotarod tests, and its effects on oxidative stress were explored by detecting several oxidative stress markers, including malondialdehyde, nitric oxide, glutathione peroxidase, and superoxide dismutase. Real-time quantitative RT-PCR and WB were used to detect the effects of ZYAND on the levels of prolyl hydroxylase domain 3 (PHD3), hypoxia-inducible factor-1α (HIF-1α), and vascular endothelial growth factor (VEGF) in the brain tissues of mice. The effect of ZYAND on the NF-κB signaling pathway was detected using a luciferase reporter gene. A human umbilical cord vascular endothelial cell angiogenesis experiment was performed to determine whether ZYAND promotes angiogenesis. The Morris water maze test and other behavioral experiments verified that ZYAND improved the neurobehavior of mice after ICH. ZYAND activated the PHD3/HIF-1α signaling pathway, inhibiting the oxidative damage caused by ICH. In angiogenesis experiments, it was found that ZYAND promoted VEGF-induced angiogenesis by upregulating the expression of HIF-1α, and NF-κB signaling regulated the expression of HIF-1α by inhibiting PHD3. ZYAND exerts a reparative effect on brain tissue damaged after ICH through the NF-κB/ PHD3/HIF-1α/VEGF signaling axis.

Influence of body mass index on the clinicopathological features of 13,995 papillary thyroid tumors

PURPOSE

This retrospective study aimed to assess the association between obesity, gender, and specific clinicopathological features in patients with papillary thyroid cancer (PTC) and whether diagnostic ultrasonography (US) is adversely affected by obesity in these patients.

MATERIALS AND METHODS

This study retrospectively analyzed 13,995 adult patients with PTC from a single medical center in China. Data stratification was performed to assess the association of obesity with US features and aggressive clinicopathological features in different models according to the World Health Organization Body Mass Index (WHO-BMI) and Chinese BMI classification (CN-BMI). The odds ratio (OR) of malignant US features and aggressive clinicopathological features was calculated from binary logistic regression models.

RESULTS

The BMI, obesity ratio, malignant US features, and aggressive pathological characteristics of males were significantly higher than those of females. After adjusting for confounding factors, the association of obesity with malignant US features and aggressive pathological characteristics was found to be sex-dependent. Next, obesity (WHO-BMI) was found to have an "interfering effect" on the US assessment of PTC (OR = 0.754, 95% CI 0.609-0.932, P = 0.009) in women. Among both sexes, obesity (WHO-BMI) increased the risk of tumor size (OR_male = 1.539 and OR_female = 1.521) and multifocality (OR_male = 1.659 and OR_female = 1.449). However, obesity did not increase the risk of capsular invasion or tumor staging in males. The above results are consistent with the CN-BMI. In addition, age was found to have an "interfering effect" on the US evaluation of malignant nodules in both sexes.

CONCLUSION

The results of our study confirm that higher BMI is significantly associated with aggressive clinicopathological features of PTC. Gender differences were present with obesity ratios and aggressive clinicopathological features being significantly higher in men.

Lymph node characteristics of 6279 N1 differentiated thyroid cancer patients

PURPOSE

This study examined the clinicopathological characteristics of 6279 N1 differentiated thyroid cancer (DTC) patients who underwent operations in our center.

METHODS

This was a retrospective longitudinal analysis. We categorized the DTC on the basis of various lymph node (LN) characteristics. Logistic regression models and multiple linear regression models were used for the correlation analysis.

RESULTS

A total of 3693 (58.8%) N1a patients and 2586 (41.1%) N1b patients were included. Patients with N1b disease had larger metastatic foci (0.5 vs. 0.15 cm), a greater number of metastatic LNs (5 vs. 2), a greater number of dissected LNs (25 vs. 7), and a smaller lymph node ratio (NR, number of positive LNs / number of sampled LNs) (23.1% vs. 28.6%) than patients in stage N1a. Comparing the clinicopathological features, we found that male, increased tumor size, multifocality, and thyroiditis increased the risk of stage N1b disease (P<0.05). Sex, multifocality, capsular infiltration, and tumor size were associated with the size of the metastatic LNs (P<0.05). Sex, capsular infiltration, and nodular goiter were associated with the NR (P<0.05). Male sex, tumor located in inferior lobe, maximal tumor diameter (MTD) <1cm, and nodular goiter were independent predictors for skip metastases (P<0.05). MTD <1cm, central neck metastasis and advanced age were independent predictors for bilateral lateral neck metastasis (BLNM) (P<0.05).

CONCLUSION

The LN characteristics of stage N1a and N1b disease were associated with significantly different features, such as sex, tumor size, multifocality, capsular infiltration, and nodular goiter.

[Screening different HPV genotypes infection and type-specific in cervical exfoliated cells of women in Yili area of Xinjiang Uygur Autonomous Region, China]

Objective: To investigate the infection status and genotype distribution of cervical human papillomavirus (HPV) in women of different ethnic groups and different ages in Yili, Xinjiang Uygur Autonomous Region (Xinjiang). Methods: By using the convenient sampling method, 54 760 women from November 2015 to May 2017 seeking for service in gynecological clinics in a general hospital in Yili, Xinjiang, were selected as the research subjects, and 3 445 samples of cervical mucous exfoliative cells were collected, and the social information of their ethnic and age was collected at the same time. The inclusion criteria were those with sexual life, cervical integrity, and ethnic groups for Han or Uygur or Kazak. PCR-reverse dot blot hybridization was used to detect HPV genotyping in exfoliated cells, and chi-square test was used to compare the difference of HPV positive rate among different ethnic groups. Then, according to ethnicity and age, the differences in positive rates of different ages and ethnic groups were compared in each layer. Results: The positive rate of HPV was 25.6% (882 cases), of which the Han, Uygur and Kazakh were 27.9% (564 cases), 22.9% (196 cases) and 21.6% (122 cases), and the difference was statistically significant (χ(2)=13.80, P=0.001). The most prevalent high-risk genotypes of Han women were HPV16/52/58, accounting for 24.8% (140 cases), 17.7% (100 cases) and 9.8% (55 cases), respectively. The most prevalent high-risk genotypes of Uygur women were HPV16/52/53, accounting for 34.2% (67 cases), 12.8% (25 cases), 9.2% (18 cases), respectively. The most prevalent high-risk genotypes of Kazak were HPV16/52/53, accounting for 37.7% (46 cases), 17.2% (21 cases), 12.3% (15 cases), respectively. The highest rate of HPV in Uygur patients aged ≥61 years was 41.5% (22 cases), and the lowest in group 36-40 years old, 15.9% (21 cases), the difference between different age groups was statistically significant (χ(2)=35.01, P<0.001). Conclusion: The positive rate of HPV infection among Han, Uygur and Kazak in Yili Prefecture of Xinjiang was different, and the HPV positive genotype differs among different ethnic groups.

[Establishment of 43-plex SNP Typing System and Its Forensic Application]

OBJECTIVES

To evaluate the application of 43-plex SNP typing system in forensic science.

METHODS

The typing of 43 SNP loci in 123 unrelated Han individuals from East China was detected by MALDI-TOF-MS. The application value of 43-plex SNP typing system was assessed according to the forensic parameters of population genetics.

RESULTS

All the 43 SNP loci of 123 individuals showed no significant departure from Hardy-Weinberg equilibrium （P>0.05）. Excepted rs1355366, rs2270529, rs10776839 and rs938283, there were 39 SNP loci had minor allele frequencies （MAF）, which were greater than 0.25. Among the 25 loci MAFs, 24 ranged from 0.4 to 0.5, while 3 were close to 0.4. The DP, CDP, PIC, Ho, PE_trio and PE_duo of the 43 SNP loci were 0.290 1-0.654 4, 1-9.8×10⁻¹¹, 0.170 8-0.500 0, 0.155 7-0.593 5, 0.085 4-0.250 0 and 0.014 6-0.125 0, respectively. The CPE_trio and CPE_duo were 0.999 986 and 0.992 436 1, respectively.

CONCLUSIONS

The 43-plex SNP typing system in present study shows a high polymorphism, which can be an effective supplement and verification for traditional STR genetic markers. It also can be used with other commercial kits for the forensic paternity testing and individual identification.

Treatment of a Pediatric Case of Severe Hemorrhagic Cystitis: Case Report and Review of Literature

Hemorrhagic cystitis is one of the complications of allogeneic hematopoietic stem cell transplantation. Treatment of hemorrhagic cystitis is difficult, especially in pediatric patients. A pediatric case of severe hemorrhagic cystitis after hematopoietic stem cell transplantation was treated in our hospital with arterial embolization combined with corticosteroid therapy because the conventional therapy was invalid for him. After the treatment, hemorrhagic cystitis was cured. During follow-up, the patient was in stable condition, with normal urine, blood cells returned to normal, bone marrow was in complete remission state, and disease-free survival for more than 8 months. Selective bladder arterial embolism followed by corticosteroid therapy successfully treated the patient.

Concurrent chemoradiotherapy with weekly nedaplatin versus radiotherapy alone in elderly patients with non-small-cell lung cancer

PURPOSE

We conduct this study to compare the efficacy and toxicity of intensity-modulated radiotherapy (IMRT) concurrent weekly nedaplatin (NDP) versus IMRT alone in the stage III/IV non-surgical elderly patients with non-small-cell lung cancer (NSCLC).

METHODS

117 patients were enrolled into our study. The patients were assigned into two different groups: radiotherapy (RT) group and chemoradiotherapy (CRT) group. Patients in RT group were treated with IMRT at a single daily dose of 2 Gy for 5 days per week, totally 52-66 Gy. The CRT group, IMRT concurrent weekly NDP at a dose of 25 mg/m².

RESULTS

In CRT group, the median survival was 11.0 months (95% confidence interval [CI], 8.894-13.106 months) and in RT group, it was 7.0 months (95% CI 5.771-8.229 months). The 1-year, 2-year, 3-year, survival rates in the combined treatment arm were higher than the radiation therapy arm (46.8 vs 25.9%, 25.1 vs 11.8%, 14.7 vs 8.0%; p < 0.001). The Cox's multiple regression analysis showed that CRT had significantly better overall survival than RT (HR 0.523; 95.0% CI 0.338-0.807; p = 0.003). The objective response rate provided that 73.3% treated with CRT compared with 51.1% (p = 0.018) received RT alone. Of the hematologic toxicities, leukocytes (35.0 vs 0%; p < 0.001), neutrophils (33.3 vs 0%; p < 0.001) were significantly more common in the CRT group than the RT group.

CONCLUSIONS

We first discovered that NDP concurrent IMRT for treating stage III/IV non-surgical elderly patients with NSCLC was good curative effect of better objective response rate and well-tolerated. However, within the low number of patients, only stage IV gained a survival benefit.

Coexistence of EGFR with KRAS, or BRAF, or PIK3CA somatic mutations in lung cancer: a comprehensive mutation profiling from 5125 Chinese cohorts

Background:

Determining the somatic mutations of epidermal growth factor receptor (EGFR)-pathway networks is the key to effective treatment for non-small cell lung cancer (NSCLC) with tyrosine kinase inhibitors (TKIs).The somatic mutation frequencies and their association with gender, smoking history and histology was analysed and reported in this study.

Methods:

Five thousand one hundred and twenty-five NSCLC patients' pathology samples were collected, and EGFR, KRAS, BRAF and PIK3CA mutations were detected by multiplex testing. The mutation status of EGFR, KRAS, BRAF and PIK3CA and their association with gender, age, smoking history and histological type were evaluated by appropriate statistical analysis.

Results:

EGFR, KRAS, BRAF and PIK3CA mutation rates revealed 36.2%, 8.4%, 0.5% and 3.3%, respectively, across the 5125 pathology samples. For the first time, evidence of KRAS mutations were detected in two female, non-smoking patients, age 5 and 14, with NSCLC. Furthermore, we identified 153 double and coexisting mutations and 7 triple mutations. Interestingly, the second drug-resistant mutations, T790M or E545K, were found in 44 samples from patients who had never received TKI treatments.

Conclusions:

EGFR exons 19, 20 and 21, and BRAF mutations tend to happen in females and non-smokers, whereas KRAS mutations were more inclined to males and smokers. Activating and resistant mutations to EGFR-TKI drugs can coexist and ‘second drug-resistant mutations', T790M or E545K, may be primary mutations in some patients. These results will help oncologists to decide candidates for mutation testing and EGFR-TKI treatment.

The atypical ubiquitin ligase RNF31 stabilizes estrogen receptor α and modulates estrogen-stimulated breast cancer cell proliferation

Estrogen receptor α (ERα) is initially expressed in the majority of breast cancers and promotes estrogen-dependent cancer progression by regulating the transcription of genes linked to cell proliferation. ERα status is of clinical importance, as ERα-positive breast cancers can be successfully treated by adjuvant therapy with antiestrogens or aromatase inhibitors. Complications arise from the frequent development of drug resistance that might be caused by multiple alterations, including components of ERα signaling, during tumor progression and metastasis. Therefore, insights into the molecular mechanisms that control ERα expression and stability are of utmost importance to improve breast cancer diagnostics and therapeutics. Here we report that the atypical E3 ubiquitin ligase RNF31 stabilizes ERα and facilitates ERα-stimulated proliferation in breast cancer cell lines. We show that depletion of RNF31 decreases the number of cells in the S phase and reduces the levels of ERα and its downstream target genes, including cyclin D1 and c-myc. Analysis of data from clinical samples confirms correlation between RNF31 expression and the expression of ERα target genes. Immunoprecipitation indicates that RNF31 associates with ERα and increases its stability and mono-ubiquitination, dependent on the ubiquitin ligase activity of RNF31. Our data suggest that association of RNF31 and ERα occurs mainly in the cytosol, consistent with the lack of RNF31 recruitment to ERα-occupied promoters. In conclusion, our study establishes a non-genomic mechanism by which RNF31 via stabilizing ERα levels controls the transcription of estrogen-dependent genes linked to breast cancer cell proliferation.

Comparison of the effects of the pretreatment and treatment with RhIL-11 on acute liver failure induced by D-galactosamine

OBJECTIVE

To compare the effects of the pretreatment and treatment with recombinant human interleukin-11 (rhIL-11) on acute liver failure induced by D-galactosamine (D-GalN).

METHODS

The Sprague Dawley (SD) male rats were randomly divided into five groups: control, model, pretreatment, treatment and repeated treatment groups. The acute liver failure model was established by intraperitoneal injections with D-GalN (1400 mg/kg). The pretreatment, treatment and repeated treatment groups were injected subcutaneously with rhIL-11 (500 µg/kg). The rats were killed 24, 48, or 72 h after the D-GalN injection. The symptoms and survival rate of the rats were analysed. Liver injury was assessed by serum ALT and AST levels and by histological analysis. The percentage of Proliferating Cell Nuclear Antigen (PCNA+) cells in the liver tissue was evaluated by immunohistochemistry.

RESULTS

Compared with the model group, the survival rate of the pretreatment group improved markedly, and these rats were protected from severe hepatic injury, as shown by the decreased serum ALT and AST levels and improved histological results. In the pretreatment group, the percentage of PCNA+ cells was significantly increased in the late stage. In contrast, the treatment and repeated treatment groups did not show improved survival rates or the prevention of severe hepatic injury, as shown by the absence of any decrease in the serum ALT and AST levels and the lack of any improvement in the histological results.The treatment and repeated treatment groups also have a significant increase in the percentage of PCNA+ cells in the late stage.

CONCLUSIONS

The pretreatment with rhIL-11 can reduce acute liver failure and protect the liver. In contrast, the treatment with rhIL-11 cannot reduce acute liver failure or protect the liver.

Is elevation of carbon dioxide concentration beneficial to seedling photosynthesis in the understory of tropical rain forests?

Cuttings of the southeast Asian tropical rain forest tree species, Pongamia pinnata (L.) Pierre were raised in growth chambers providing a photosynthetic photon flux density (PPFD) of 60 micromol m(-2) s(-1) with either a low or a high red:far-red light ratio (LR and HR, repectively). The chambers were supplied with air containing CO(2) at a concentration of either 400 (LR4 and HR4, respectively) or 800 micromol mol(-1) (HR8 and LR8, respectively). After 4 months, leaf morphology and photosynthetic characteristics were determined. Relative to HR4, the LR4 treatment increased leaf area and total chlorophyll concentration (Chl) by 24 and 25%, respectively, but reduced leaf mass per unit area (LMA) by 19%. Elevated [CO(2)] significantly increased leaf area and LMA but did not affect Chl of LR or HR plants. Leaf nitrogen concentration was unaffected by the red:far-red light ratio but decreased significantly in seedlings in the elevated [CO(2)] treatment. Photosynthesis measured in situ under the growth conditions of ambient light and [CO(2)] (A(amb)) was 30% lower on an area basis and 14% lower on a mass basis in LR4 plants than in HR4 plants. Elevated [CO(2)] reduced the activity of ribulose-1,5-bisphosphate carboxylase/oxygenase and thus decreased light-saturated photosynthetic rate in both HR and LR plants. Elevated [CO(2)] increased mean leaf area and decreased respiration rates in both LR and HR plants. The LR8 plants had significantly higher A(amb) than LR4 plants, but similar A(amb) to HR8 plants.

Characterization of the photosynthetic induction response in a Populus species with stomata barely responding to light changes

The photosynthetic induction response is constrained by stomatal and biochemical limitations. However, leaves in some plants like Populus koreana x trichocarpa cv. Peace (a hybrid clone) may have little stomatal limitation because their stomata barely respond to changes in photon flux density (PFD). We examined the induction responses of leaves of well-watered and dehydrated P. koreana x trichocarpa plants grown in a high-light or a low-light regime. With an increase in PFD from 50 to 500 micromol m(-2) s(-1), steady-state stomatal conductance (g(s)) increased by only 0.25-8.2%, regardless of the initial g(s), but steady-state assimilation rate (A) increased by 550-1810%. Photosynthetic induction times required to reach 50% (IT50) and 90% (IT90) of A at high PFD were 60-90 s and 210-360 s, respectively. Examination of the dynamic relationships between A and g(s), and between A and intercellular CO2 concentration, indicated that the induction limitation was imposed completely by the biochemical components within 30-40 s after the PFD increase. Values of IT50 and IT90 were significantly higher in low-light leaves than in high-light leaves, whereas the induction state at 60 s and the induction efficiency at 60 and 120 s after the increase in PFD were lower in low-light leaves than in high-light leaves. Dehydration reduced leaf water potential (psi) significantly, resulting in a significantly decreased initial g(s). Leaf water potential had no significant effects on induction time in high-light leaves, but a low psi significantly reduced the induction time in low-light leaves. We conclude that the photosynthetic induction response was limited almost completely by biochemical components because the stomata barely responded to light changes. The biochemical limitation appeared to be higher in low-light leaves than in high-light leaves. Mild water stress may have reduced steady-state A and g(s), but it had little effect on the photosynthetic induction response in high-light leaves.

Cytoskeletal changes in platelets induced by thrombin and phorbol myristate acetate (PMA)

Changes in shape, and aggregation that accompanies platelet activation, are dependent on the assembly and reorganization of the cytoskeleton. To assess the changes in cytoskeleton induced by thrombin and PMA, suspensions of aspirin-treated,32P-prelabeled, washed pig platelets in Hepes buffer containing ADP scavengers were activated with thrombin, and with PMA, an activator of protein kinase C. The cytoskeletal fraction was prepared by adding Triton extraction buffer. The Triton-insoluble (cytoskeletal) fraction isolated by centrifugation was analysed by SDS-PAGE and autoradiography. Incorporation of actin into the Triton-insoluble fraction was used to quantify the formation of F-actin. Thrombin-stimulated platelet cytoskeletal composition was different from PMA-stimulated cytoskeletal composition. Thrombin-stimulated platelets contained not only the three major proteins: actin (43 kDa), myosin (200 kDa) and an actin-binding protein (250 kDa), but three additional proteins of Mr56 kDa, 80 kDa and 85 kDa in the cytoskeleton, which were induced in by thrombin dose-response relationship. In contrast, PMA-stimulated platelets only induced actin assembly, and the 56 kDa, 80 kDa and 85 kDa proteins were not found in the cytoskeletal fraction. Exposure of platelets to thrombin or PMA induced phosphorylation of pleckstrin parallel to actin assembly. Staurosporine, an inhibitor of protein kinase C, inhibited actin assembly and platelet aggregation induced by thrombin or PMA, but did not inhibit the incorporation of 56 kDa, 80 kDa and 85 kDa into the cytoskeletal fraction induced by thrombin. These three extra proteins seem to be unrelated to the induction of protein kinase C. We conclude that actin polymerization and platelet aggregation were induced by a mechanism dependent on protein kinase C, and suggest that thrombin-activated platelets aggregation could involve additional cytoskeletal components (56 kDa, 80 kDa, 85 kDa) of the cytoskeleton, which made stronger actin polymerization and platelet aggregation more.

[Comparison of the cytotoxicity of five constituents from Pteris semipinnata L. in vitro and the analysis of their structure-activity relationships]

The antitumor constituents were isolated from Pteris semipinnata L. (PsL), a Chinese traditional herb, and screened using tetrazolium salt (MTT) method. Their cytotoxic effects in vitro on several human tumor cell lines were studied. Compounds 5F, 6F, A and the ethanolic extract of PsL (PSE) were shown to have strong cytotoxicity against five cell lines: human liver adenocarcinoma cell line (HePG II), human lung adenocarcinom a cell line (SPC-A-1), human gastric adenocarcinoma cell line (MGC-803), human nasopharyngeal carcinoma cells in low differentiation (CNE-2Z) and human liver adenocarcinoma cell line (BEL-7402) in different degrees in a dose-dependent manner; compound 6F was the most active one, whose IC50 after 72 h treatment for the above five cell lines were 0.343 +/- 0.003, 0.115 +/- 0.022, 0.590 +/- 0.032, 0.328 +/- 0.066 and 0.221 +/- 0.058 microgram.ml-1, respectively. Compounds A and 5F were less active; no cytotoxicity of compounds 4F and B were detected on the five cell lines. Analysis of the relationship between structure and activity revealed that the antitumor activity portion in the structure is the alpha, beta-methylene cyclopentanone moiety, and the site and number of the hydroxy groups affect the cytotoxicity of these agents significantly.

Isolation, cloning and characterization of a low-molecular-mass purine nucleoside- and nucleotide-binding protein

A purine nucleoside- and nucleotide-binding protein has been isolated from extracts of rat and rabbit heart, calf aortic smooth muscle and rat liver using an affinity column containing adenosine bound through the N6-position. The protein, which was eluted by adenosine, was cloned and expressed in Escherichia coli. The deduced amino acid sequence has a calculated Mr of 13693 (p13.7). The expressed protein has properties identical with the protein isolated from heart and liver, including an anomalous, apparent Mr of 15300, observed on gel electrophoresis. Gel filtration shows it to be a dimer. p13.7 differs by only three amino acids out of 125 from protein kinase C inhibitor 1 [Pearson, DeWald, Mathews, Mozier, Zürcher-Neely, Heinrikson, Morris, McCubbin, McDonald, Fraser et al. (1990) J. Biol. Chem. 265, 4583-4591]. However, we have not been able to demonstrate inhibition of protein kinase C by physiological concentrations of p13.7, regardless of whether it was isolated from tissue extracts or expressed in E. coli. p13.7 is a member of the histidine triad motif family of proteins [Séraphin (1992) J. DNA Sequencing Mapping 3, 177-179]. The affinity of p13.7 for a number of different purine nucleosides and nucleotides, as measured by fluorescence titration and gel filtration, falls within the range 5-50 microM. On the basis of these properties and its crystal structure [Brenner, Garrison, Gilmour, Peisach, Ringe, Petsko and Lowenstein (1997) Nature Struct. Biol. 4, 231-238], we have coined the acronym HINT (histidine triad nucleotide-binding motif) to describe the family of proteins of which p13.7 is a member. Other proteins that bind to the affinity column have been identified as malate and lactate dehydrogenases, cAMP-binding proteins, adenosine kinase and S-adenosylhomocysteine hydrolase.

[Chemical components of Codonopsis pilosula (Franch.) Nannf. var. volubilis (Nannf.) L.T. Shen]

Ten compounds were isolated from Codono psis pilosula var. volubilis. Six of them were characterized as friedelin, taraxerol, alpha-spinasterol, alpha-spinasterol-beta-D-glucopyranoside, n-butyl-alpha-D-fructofuranoside and n-butyl-beta-D-fructopyranoside.