Unveiling the inhibitory mechanisms of chromium exposure on microbial reductive dechlorination: Kinetics and microbial responses

Chromium and organochlorine solvents, particularly trichloroethene (TCE), are pervasive co-existing contaminants in subsurface aquifers due to their extensive industrial use and improper disposal practices. In this study, we investigated the microbial dechlorination kinetics under different TCE-Cr(Ⅲ/VI) composite pollution conditions and elucidated microbial response mechanisms based on community shift patterns and metagenomic analysis. Our results revealed that the reductive dechlorinating consortium had high resistance to Cr(III) but extreme sensitivity to Cr(VI) disturbance, resulting in a persistent inhibitory effect on subsequent dechlorination. Interestingly, the vinyl chloride-respiring organohalide-respiring bacteria (OHRB) was notably more susceptible to Cr(III/VI) exposure than the trichloroethene-respiring one, possibly due to inferior competition for growth substrates, such as electron donors. In terms of synergistic non-OHRB populations, Cr(III/VI) exposure had limited impacts on lactate fermentation but significantly interfered with H2-producing acetogenesis, leading to inhibited microbial dechlorination due to electron donor deficiencies. However, this inhibition can be effectively mitigated by the amendment of exogenous H2 supply. Furthermore, being the predominant OHRB, Dehalococcoides have inherent Cr(VI) resistance defects and collaborate with synergistic non-OHRB populations to achieve concurrent bio-detoxication of Cr(VI) and TCE. Our findings expand the understanding of the response patterns of different functional populations towards Cr(III/VI) stress, and provide valuable insights for the development of in situ bioremediation strategies for sites co-contaminated with chloroethene and chromium.

The effects of arsenic on dechlorination of trichloroethene by consortium DH: Microbial response and resistance

Inorganic arsenic and organochlorines are frequently co-occurring contaminants in anoxic groundwater environments, and the bioremediation of their composite pollution has long been a rigorous predicament. Currently, the dechlorination behaviors and stress responses of microbial dechlorination consortia to arsenic are not yet fully understood. This study assessed the reductive dechlorination performance of a Dehalococcoides-bearing microcosm DH under gradient concentrations of arsenate [As(V)] or arsenite [As(III)] and investigated the response patterns of different functional microorganisms. Our results demonstrated that although the dechlorination rates declined with increasing arsenic concentrations in both As(III/V) scenarios, the inhibitory impact was more pronounced in As(III)-amended groups compared to As(V)-amended groups. Moreover, the vinyl chloride (VC)-to-ethene step was more susceptible to arsenic exposure compared to the trichloroethene (TCE)-to-dichloroethane (DCE) step, while high levels of arsenic exposure [e.g. As(III) > 75 μM] can induce significant accumulation of VC. Functional gene variations and microbial community analyses revealed that As(III/V) affected reductive dechlorination by directly inhibiting organohalide-respiring bacteria (OHRB) and indirectly inhibiting synergistic populations such as acetogens. Metagenomic results indicated that arsenic metabolic and efflux mechanisms were identical among different Dhc strains, and variations in arsenic uptake pathways were possibly responsible for their differential responses to arsenic exposures. By comparison, fermentative bacteria showed high potential for arsenic resistance due to their inherent advantages in arsenic detoxification and efflux mechanisms. Collectively, our findings expanded the understanding of the response patterns of different functional populations to arsenic stress in the dechlorinating consortium and provided insights into modifying bioremediation strategies at co-contaminated sites for furtherance.

Bioelectrochemical system accelerates reductive dechlorination through extracellular electron transfer networks

Bioelectrochemical system is considered as a promising approach for enhanced bio-dechlorination. However, the mechanism of extracellular electron transfer in the dechlorinating consortium is still a controversial issue. In this study, bioelectrochemical systems were established with cathode potential settings at -0.30 V (vs. SHE) for trichloroethylene reduction. The average dechlorination rate (102.0 μM Cl·d-1) of biocathode was 1.36 times higher than that of open circuit (74.7 μM Cl·d-1). Electrochemical characterization via cyclic voltammetry illustrated that electrostimulation promoted electrochemical activity for redox reactions. Moreover, bacterial community structure analyses indicated electrical stimulation facilitated the enrichment of electroactive and dechlorinating populations on cathode. Metagenomic and quantitative polymerase chain reaction (qPCR) analyses revealed that direct electron transfer (via electrically conductive pili, multi-heme c-type cytochromes) between Axonexus and Desulfovibrio/cathode and indirect electron transfer (via riboflavin) for Dehalococcoides enhanced dechlorination process in BES. Overall, this study verifies the effectiveness of electrostimulated bio-dechlorination and provides novel insights into the mechanisms of dechlorination process enhancement in bioelectrochemical systems through electron transfer networks.

Developmental synergism in the management of oral potentially malignant disorders

Oral potentially malignant disorders (OPMDs) are associated with an increased risk of occurrence of cancers of the oral cavity or lips. The unifying theme of OPMDs is their potential risk for cancer development. Therefore, the primary objective of the management should be to prevent carcinogenesis. Beyond diagnosis, current strategies for the management of OPMDs predominantly include non-surgical and surgical interventions and a "watch-and-see" approach, such as disease monitoring or surveillance, and preventive strategies. Though no optimal clinical treatment has gained universal approval for reducing or preventing malignant development of OPMDs. Therefore, an urgent need exits for improved treatment properties and effective predictive markers for OPMDs treatment. This review aims to outline recent synergism regarding to the management of OPMDs. Developing new technologies and improved application parameters to promote the treatment efficacy and a novel management prescription approach to OPMDs are proposed.

[Association of BMI with acute exacerbation in mild to moderate chronic obstructive pulmonary disease patients in community: a prospective study]

Objective: BMI may play a protective role in reducing the mortality rate of patients with chronic obstructive pulmonary disease (COPD), but its effect on acute exacerbation of COPD remain unclear. Methods: Subjects were selected from the COPD patients registration system established in 2014 in Pudong new district, Shanghai. COPD patients from 8 communities were selected by cluster sampling and follow up was conducted prospectively for 18 months. Basic information and BMI were obtained from baseline survey, and acute exacerbations were collected during follow-up. The association between BMI and risk of acute exacerbation was evaluated by using multiple negative binomial regression. Results: Among 328 community COPD patients, 295 who completed the follow up were included in the analysis, in whom 96.3% (284/295) were mild COPD patients. During the follow-up, 11.1% (33/295) of the patients reported acute exacerbation. The results of multiple negative binomial regression suggested that, the risk for acute exacerbation decreased with the increase of BMI (IRR=0.85, 95%CI:0.73-0.98), overweight patients with BMI ≥25.0 kg/m² (IRR=0.36, 95%CI:0.13-0.91) or moderate BMI (T₂ vs. T₁, IRR=0.31, 95%CI:0.11-0.77) had lower risk for acute exacerbation compared with the patients with normal or low BMI. BMI had a linear correlation with the risk of acute exacerbation. Conclusion: The risk for acute exacerbation in patients with mild or moderate COPD in communities decreased with the increase of BMI, and being overweight might be a protective factor for the acute exacerbation of COPD.

Parameters optimization method for the time-delayed reservoir computing with a nonlinear duffing mechanical oscillator

Reservoir computing (RC) is a recently introduced bio-inspired computational framework capable of excellent performances in the temporal data processing, owing to its derivation from the recurrent neural network (RNN). It is well-known for the fast and effective training scheme, as well as the ease of the hardware implementation, but also the problematic sensitivity of its performance to the optimizable architecture parameters. In this article, a particular time-delayed RC with a single clamped-clamped silicon beam resonator that exhibits a classical Duffing nonlinearity is presented and its optimization problem is studied. Specifically, we numerically analyze the nonlinear response of the resonator and find a quasi-linear bifurcation point shift of the driving voltage with the driving frequency sweeping, which is called Bifurcation Point Frequency Modulation (BPFM). Furthermore, we first proposed that this method can be used to find the optimal driving frequency of RC with a Duffing mechanical resonator for a given task, and then put forward a comprehensive optimization process. The high performance of RC presented on four typical tasks proves the feasibility of this optimization method. Finally, we envision the potential application of the method based on the BPFM in our future work to implement the RC with other mechanical oscillators.

[Relationship of body mass index, waist circumference and waist-to-hip ratio with diabetes mellitus in community residents aged 15 years old and above in Pudong new district, Shanghai]

Objective: To analyze the relationship of body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR) with diabetes mellitus in community residents aged ≥15 years in Pudong new district of Shanghai, and provide evidence for the prevention and treatment of diabetes mellitus. Methods: Using multi-stage stratified cluster sampling method, a total of 7 194 community residents aged ≥15 years were surveyed by using questionnaire, physical examination and laboratory tests in 2016. The relationship of BMI, waist circumference and waist-hip ratio with diabetes mellitus was analyzed by χ(2) test, single factor linear correlation and logistic regression analyses. Results: In 2016, the crude prevalence rate of diabetes mellitus in Pudong was 27.37%, which was 12.75% after standardization. The prevalence rate of diabetes mellitus was slightly higher in men than in women and was increased with age. The levels of FPG, 2 h plasma glucose and HbA1c were positively correlated with BMI, WC and WHR. After adjusting the confounding factors, multiple logistic regression analysis showed that obesity (OR=1.351, P<0.01), excessive waist circumference (OR=1.255, P<0.01) and high WHR (OR=1.291, P<0.01) were risk factors for diabetes mellitus. Conclusions: The increase of obesity, WC and WHR will increase the risk for diabetes mellitus. It is important to maintain healthy weight, especially the control of WC and WHR, reduce the accumulation of abdominal fat to reduce the risk for diabetes mellitus.

Effect of mannose on the lung function of rats with acute pancreatitis

The present study aimed to investigate the mechanisms by which mannose protects the lung injury induced in rats with acute pancreatitis (AP). An AP combined with Acute Lung Injury (ALI) model was established. A total of 90 healthy adult male Sprague-Dawley rats (300±50g weight) were randomly divided into three groups: sham operation group (SO group), severe acute pancreatitis lung injury group (SAP group), and mannose intervention group (MT group). Subsequently, each group was divided into two subgroups based on the time passed from intervention, namely 6 and 12 h. Each subgroup comprised 15 rats. The ratio of wet/dry weight of the lung tissue exhibited no significant change at different time points in the SO group. This parameter was significantly increased in the SAP group compared with the SO group at each time point of the treatment (P less than 0.05) and it was significantly lower in the MT group than that in the AP group (P less than 0.05) and it was significantly increased in the AP group at each time (P less than 0.05) compared with the SO group. The levels of TNF-α in the lung tissue in the SO group exhibited no significant change at different time points, but they were significantly decreased in the MT group at each time point (P less than 0.05) compared with the SAP group. The mannose receptor (MR) mRNA and protein levels in the lung tissues exhibited no significant change at different time points. The mRNA and protein levels of MR in the SAP group were significantly decreased at each time point (P less than 0.05) compared with the SO group. The mRNA and protein levels of MR, in the lung tissue of the MT group were significantly increased at each time point compared with the SAP group (P less than 0.05). Mannose could reduce the injury caused to the lung tissue of rats with severe acute pancreatitis by up-regulation of the expression of MR mRNA and protein.

Expression and clinical significance of rhubarb on serum amylase and TNF-alpha of rat model of acute pancreatitis

The aim of this study was to evaluate the therapeutic effect of rhubarb extract on acute pancreatitis. Ninety-six healthy Sprague Dawley rats, weighing 301±5.12 g were randomly divided into 4 groups: sham surgery (group A), acute pancreatitis model (group B), acute pancreatitis with normal saline (group C), and acute pancreatitis model with rhubarb (group D). The levels of serum amylase (AMY) and TNF-α were measured at 1st, 6th, 12th and 24th hour after modeling, and the pancreatic tissue were used to observe the pathologic changes. Compared to the sham group, the serum AMY and serum tumor necrosis factor (TNF-α) levels were significantly increased in the other groups (p <0.05). Compared to the model group and the saline group, the serum AMY, serum TNF-α level and pathological changes of rats in the rhubarb group were significantly lower (p <0.05). The serum AMY and TNF-α levels increased in acute pancreatitis. The rhubarb reduced the serum AMY and TNF-α level in rats with acute pancreatitis and reduced the pathological changes of pancreas and other tissues.

Complex relation among Health Belief Model components in TB prevention and care

OBJECTIVES

This study aims to explore the relationships among components of the Health Belief Model, tuberculosis (TB) preventive behavior, and intention of seeking TB care.

STUDY DESIGN

Cross section study.

METHODS

Using convenience sampling, 1154 rural-to-urban migrant workers were selected between the ages of 18-50 years in six urban areas of three provinces in China. The survey was conducted by individual, face-to-face interviews with a standardized questionnaire. Lisrel 8.7 was used to conduct path analysis.

RESULTS

The knowledge and benefits components of the Health Belief Model predicted preventive behaviors: cover nose/mouth when coughing or sneezing (β = 0.24, 0.33 respectively), evade others' coughs (β = 0.13, 0.25) and also predicted seeking TB care (β = 0.27, 0.19). Susceptibility and severity also predicted seeking TB care (β = 0.12, 0.16). There were also important relationships among model components. Knowledge of TB predicted both susceptibility (β = 0.32-0.60) and severity (β = 0.41-0.45). Further, each of susceptibility (β = 0.30) and severity (β = 0.41) predicted perceived benefits of preventive care.

CONCLUSION

Thus, a path from knowledge, through severity and susceptibility, and then through benefits predicted prevention and TB care seeking behaviors.

[Semen expulsion under the ureterocystoscope]

OBJECTIVE

To determine the exact location of the opening of the ejaculatory duct in men and provide some basic anatomical evidence for seminal vesiculoscopy and the treatment of ejaculatory duct obstruction.

METHODS

We performed ureterocystoscopy for 21 male patients aged 26 - 47 years with hematuria (n = 12), hematospermia (n = 2), glandular cystitis (n = 6), and anejaculation after radical resection of rectal carcinoma (n = 1), and meanwhile, with the consent of the patients, massaged the prostate and ejaculatory duct and observed the outlet of the expelled fluid. Under the microscope, we described the fluid samples with sperm as the expulsion from the ejaculatory duct.

RESULTS

Ureterocystoscopy showed that the exact anatomical sites of the expulsion of prostatic fluid and semen in the patients were the side and lower side of the prostatic utricle opening above the verumontanum and the ventral side of the verumontanum. Quantities of sperm were found in the expulsion fluid of 13 of the patients, and no expulsion, including semen, was seen from the prostatic utricle opening.

CONCLUSION

Anatomically, the ejaculatory duct openings of males are located at the two sides of the verumontanum adjacent to the opening of the prostatic utricle, rather than in the prostatic utricle above the verumontanum.

[Outcomes of IVF-ET and percentage of morphologically normal sperm before and after swim-up treatment]

OBJECTIVE

To study the relationship between sperm morphology and the outcomes of in vitro fertilization-embryo transfer (IVF-ET) before and after swim-up treatment of sperm on the day of oocyte retrieval.

METHODS

This study included 94 couples to be treated by IVF-ET for tubal factor infertility. Sperm samples were collected on the day of oocyte retrieval and sperm morphology evaluated according to the Kruger criteria before and after swim-up treatment. Based on the results of morphological evaluation, the sperm samples were divided into groups A1 (morphologically normal sperm > or = 10% after swim-up treatment), A2 (morphologically normal sperm < 10% after swim-up treatment), B1 (morphologically normal sperm > or = 10% before swim-up treatment) and B2 (morphologically normal sperm < 10% before swim-up treatment). The outcomes of IVF-ET treatment were compared between groups A1 and A2 as well as between B1 and B2.

RESULTS

After swim-up treatment, the rates of fertilization, cleavage, good quality embryo, clinical pregnancy and embryo implantation of group A1 were (72.72 +/- 3.35)%, (95.64 +/- 2.04)%, (24.39 +/- 4.57)%, 50.00% and 23.87%, respectively, while those of group A2 were (70.27 +/- 8.82)%, (94.82 +/- 4.94)%, (13.45 +/- 7.39)%, 9.52% and 6.25%, respectively, the latter three indexes remarkably higher in A1 than in A2 (P < 0.05), but the differences in the former two not statistically significant (P > 0.05). Before swim-up treatment, the above five indexes were (72.90 +/- 4.23)%, (95.20 +/- 2.61)%, (23.35 +/- 5.19)%, 39.58% and 18.35% in group B1, as compared with (71.33 +/- 5.10)%, (95.71 +/- 2.88)%, (20.18 +/- 6.15)%, 41.86% and 21.28% in group B2, with no statistically significant differences between the two groups (P > 0.05).

CONCLUSION

The percentage of morphologically normal sperm after swim-up treatment on the day of oocyte retrieval may be a valuable predictor of the outcomes of IVF-ET.

The role of secondary cytoreductive surgery for recurrent mucinous epithelial ovarian cancer (mEOC)

BACKGROUND

Mucinous epithelial ovarian cancer (mEOC) may exhibit a distinct biological behavior in epithelial ovarian cancer (EOC). The role of secondary cytoreductive surgery was evaluated in patients with recurrent mEOC, and the prognosis was assessed.

METHODS

Twenty-one patients with stages IIc to IV mEOC who experienced disease recurrence and received secondary cytoreductive surgery at Fudan University Cancer Hospital between Jan. 1997 and Dec. 2005 were retrospectively reviewed. Survival curves were generated using the Kaplan-Meier method and the significant comparison of survival rate was estimated by the log-rank test.

RESULTS

The median progression-free interval (PFI) was 14 months (range, 5-46 months) after the first cytoreduction. Seven patients (33%) who received secondary cytoreductive surgery were optimally cytoreduced with residual disease less than or equal 1cm, and the other 14 patients (67%) underwent suboptimal surgical cytoreduction. The overall median survival time was 27 months (range, 8-64 months). The median survival time after recurrence was 10 months (range, 3-32 months). There was no significant statistical difference in median survival between patients with optimal and suboptimal secondary surgical cytoreduction, with an estimated survival of 10 months and 9.8 months, respectively (P>0.05).

CONCLUSION

Optimal primary cytoreductive surgery for advanced mEOC was very important. Once it recurs, the prognosis is very poor. Patients with recurrent mEOC should be carefully assessed before performing secondary cytoreductive surgery, as this may have limited impact on the overall survival rates.

Agrobacterium-mediated transformation of embryogenic cultures and plant regeneration in Vitis rotundifolia Michx. (muscadine grape)

A method to produce transgenic plants of Vitis rotundifolia was developed. Embryogenic cultures were initiated from leaves of in vitro grown shoot cultures and used as target tissues for Agrobacterium-mediated genetic transformation. A green fluorescent protein/neomycin phosphotransferase II (gfp/nptII) fusion gene that allowed for simultaneous selection of transgenic cells based on GFP fluorescence and kanamycin resistance was used to optimize parameters influencing genetic transformation. It was determined that both proembryonal masses (PEM) and mid-cotyledonary stage somatic embryos (SE) were suitable target tissues for co-cultivation with Agrobacterium as evidenced by transient GFP expression. Kanamycin at 100 mg l(-1) in the culture medium was effective in suppression of non-transformed tissue and permitting the growth and development of transgenic cells, compared to 50 or 75 mg l(-1), which permitted the proliferation of more non-transformed cells. Transgenic plants of "Alachua" and "Carlos" were recovered after secondary somatic embryogenesis from primary SE explants co-cultivated with Agrobacterium. The presence and stable integration of transgenes in transgenic plants was confirmed by PCR and Southern blot hybridization. Transgenic plants exhibited uniform GFP expression in cells of all plant tissues and organs including leaves, stems, roots, inflorescences and the embryo and endosperm of developing berries.

Transgenic plants from shoot apical meristems of Vitis vinifera L. "Thompson Seedless" via Agrobacterium-mediated transformation

Shoot apical meristem explants of Vitis vinifera "Thompson Seedless" were used for Agrobacterium-mediated genetic transformation. It was determined that the meristems had to be subjected to a dark growth phase then wounded to obtain transgenic plants. Morphological and histological studies illustrated the role of wounding to expose apical meristem cells for transformation. A bifunctional egfp/nptII fusion gene was used to select kanamycin resistant plants that expressed green fluorescent protein (GFP). Kanamycin at a concentration of 16 mg L(-1) in selection medium resulted in recovery of non-chimeric transgenic plants that uniformly expressed GFP, whereas 8 mg L(-1) kanamycin allowed non-transgenic and/or chimeric plants to develop. Polymerase chain reaction (PCR) and Southern blot analyses confirmed the presence of transgenes and their stable integration into the genome of regenerated plants. Up to 1% of shoot tips produced stable transgenic cultures within 6 weeks of treatment, resulting in a total of 18 independent lines.

Self-assembly of novel [3]- and [2]rotaxanes with two different ring components: donor-acceptor and hydrogen bonding interactions and molecular-shuttling behavior

Three of the first kind of hetero[3]rotaxanes, which comprise one linear component and one neutral and one tetracationic ring component, have been assembled by using the intermolecular hydrogen bonding and donor-acceptor interactions. Three neutral [2]rotaxanes and three tetracationic [2]rotaxanes have also been synthesized as intermediate products or for the sake of property comparison. The linear molecules are incorporated with two glycine subunits, for templating the formation of the neutral tetraamide cyclophane, and one or two hydroquinone subunits, for inducing the formation of the tetracationic cyclophane. Variable-temperature (1)H NMR investigation reveals that the shuttling behavior of the tetracationic ring component along the linear component is substantially influenced by the existence of the neutral ring component. The spatial repelling interaction of the neutral ring on the electron-deficient tetracationic ring simultaneously weakens the latter's "positioning" tendency at both electron-rich hydroquinone sites of the linear component. As a result, the activation energy associated with the shuttling process of the tetracationic ring between the two hydroquinone sites is remarkably reduced in comparison to that of the shuttling process of the corresponding neutral ring-free [2]rotaxanes. For the first time, the rotation of the dipyridinium subunit around the axis formed by the two methylene groups connecting them within the tetracationic cyclophane has been investigated by variable-temperature (1)H NMR spectroscopy and the associated kinetic data have also been successfully obtained. Furthermore, the UV-vis and fluorescent properties of the new [2]- and [3]rotaxanes have been studied. The results demonstrate that [3]rotaxanes with different ring components possess unique kinetic features that are not available in [3]rotaxanes with identical ring components.

Impact of secondary cytoreductive surgery on survival of patients with advanced epithelial ovarian cancer

AIMS

To investigate the impact on survival of secondary cytoreduction for advanced epithelial ovarian cancer and variables influencing redebulking surgical outcome.

METHODS

Between 1986 and 1997, 106 patients who received secondary cytoreductive surgery and consequent second-line chemotherapy for stages III and IV epithelial ovarian cancer were retrospectively reviewed. The optimal residual disease cut-off was 1.0 cm. The Cox proportional regression model and logistic stepwise regression were used in statistical processing of the data.

RESULTS

The median age of the patients was 50 years (range, 26-77 years). Optimal secondary cytoreduction was achieved in 46 of 106 patients (43.4%). There was a significant difference in survival between patients who were optimally cytoreduced compared to those suboptimaly cytoreduced, with an estimated median survival in the optimal group of 20 months vs 8 months in the suboptimal group ((2)=42.03, P=0.0000). When factorized, patients had significant survival benefit from optimal secondary cytoreduction for recurrent disease and interval cytoreduction. Survival was adversely influenced by progression-free interval < or =12 months (P=0.0078), residual disease >1 cm (P=0.0001) and presence of refractory ascites (P=0.0001). The probability of successful redebulking surgery was affected by presence of refractory ascites (P=0.0023) in all 106 patients and by the ascites (P=0.0072) and residual disease at initial operation in recurrent disease (P=0.0096).

CONCLUSION

Secondary surgical cytoreduction surgery significantly lengthened survival for patients with recurrent epithelial ovarian cancer or those receiving interval cytoreduction. Patients with refractory ascites, however, were not suitable for aggressive secondary surgery, and redebulking surgery for those with residual disease of >1.0 cm after primary operation should be considered prudently in recurrent disease.

Effect of cytoreductive surgery on survival of patients with recurrent epithelial ovarian cancer

BACKGROUND AND OBJECTIVES

The value of secondary cytoreductive surgery is still controversial, especially in patients with recurrent epithelial ovarian cancer. In this retrospective study, we investigated the effect on survival of secondary cytoreduction for recurrent disease and variables influencing redebulking surgical outcome.

METHODS

Between 1986 and 1997, 60 patients who received primary cytoreductive surgery and platinum-based chemotherapy for stage III and IV epithelial ovarian cancer experienced disease recurrence at least 6 months after completion of primary therapy, and secondary surgical cytoreduction was performed. The optimal residual disease cutoff was 1.0 cm. The Cox proportional regression model and Logistic stepwise regression were used in statistical processing of the data.

RESULTS

The median progression-free interval between the two operations was 13 months (range, 6-56 months). Optimal secondary cytoreduction was achieved in 23 patients (38.33%). There was a significant difference in survival between patients who were optimally cytoreduced compared to those suboptimally cytoreduced, with an estimated median survival in the optimal group of 19 months vs. 8 months in the suboptimal group (chi(2) = 22.04, P = 0.0000). Prognosis of survival for individuals with progression-free interval >12 months was better than that of those with the interval </=12 months (chi(2) = 5.22, P = 0.0224). Patients with ascites at disease recurrence suffered a pessimistic outcome, with an estimated median survival of 6 vs. 13 months in those without ascites (chi(2) = 13.99, P = 0.0002). Multivariate analysis strongly suggested that residual disease after second operation, ascites at disease recurrence, and progression-free interval were independent prognostic factors of survival. Logistic stepwise regression revealed that recurrent ascites (P = 0.0072, relative risk = 20.36) and residual disease after the second operation (P = 0.0096, relative risk = 5.16) were important determinants of secondary surgical outcome.

CONCLUSIONS

Secondary cytoreductive surgery significantly lengthened survival for patients with recurrent epithelial ovarian cancer. Patients with ascites at disease recurrence, however, were not suitable for aggressive secondary surgery, and redebulking surgery for those with residual disease of >1.0 cm after primary operation should be considered prudently.

Epithelial ovarian cancer presenting initially with extraabdominal or intrahepatic metastases: a preliminary report of 25 cases and literature review

The purpose of this study was to investigate the clinical features of patients with epithelial ovarian cancer (EOC) that are initially categorized as extraabdominal adenocarcinoma of unknown primary. Twenty-five patients with EOC, who were treated in the Cancer Hospital of Shanghai Medical University from January 1986 to December 1997, and manifesting as extraperitoneal or liver parenchyma metastases at the time of presentation without detectable ovarian tumors, were retrospectively studied. Sixteen patients (64%) were optimally surgical debulked. When compared with 52 other women with stage IV EOC, 20 patients who initially sought treatment for extraabdominal metastases experienced a better prognosis, with an estimated median survival of 24 months versus 10 months (p = 0.0427). The median survival was 30 months in patients with pleural effusion or supraclavicular lymph node metastases versus 19 months in those with spread to other sites (p = 0.0264). The prognosis of such cases, mainly for those with supraclavicular lymphadenopathy or malignant pleural effusion, is better than that for other stage IV EOC patients, probably because most of the patients who initially had distant metastases were generally in condition that permitted aggressive surgery or multicycle chemotherapy.

Cytoreductive surgery for stage IV epithelial ovarian cancer

We tried to determine the role of cytoreductive surgery for stage IV epithelial ovarian cancer and in what conditions this surgical procedure could carry the best benefits. From January 1986 to December 1997, seventy-one of 73 patients with stage IV epithelial ovarian cancer who were treated in Cancer Hospital of Shanghai Medical University were retrospectively reviewed. Clinical information including age, grade, histology, presence of ascites, size of residual disease, site of extra-abdominal metastasis, whether initially presenting as metastatic disease or not, neo-adjuvant chemotherapy, platinum-based chemotherapy and second-line chemotherapy was obtained. Survival was calculated by life-table and survival curves were computed using the Kaplan-Meier method with differences in survival estimated by log-rank test. Independent prognostic factors were identified by Cox's proportional hazards regression model. The median age of the patients' population was 54 years (range 22-82), median follow-up time was 12 months (range 3 to 130) and estimated 5-year survival rate 6.1%. Thirty out of 71 (42.3%) patients were successfully debulked (< or = 1 cm) at the time of initial surgery. There was a significant difference in five-year survival rate between patients optimally (14.1%) vs suboptimally (0%) cytoreduced, with an estimated median survival in the optimal group of 23 months vs 9 months in the suboptimal group (P=0.0001, long-rank test). When the variables were factorized, only in patients with malignant pleural effusion or positive supraclavicular lymph nodes, optimal cytoreduction could get the greatest benefits. Multivariate analysis revealed that the size of residual disease and ascites were independent factors of survival. However, only ascites was the prognostic factor of progression-free survival. Optimal cytoreductive surgery is an important determinant of survival in women with stage IV epithelial ovarian cancer, mainly in those with malignant pleural effusion or positive supraclavicular lymph node pathology.

PEBA regimen (cisplatin, etoposide, bleomycin, and adriamycin) in the treatment of drug-resistant choriocarcinoma

Twenty-six drug-resistant choriocarcinoma patients were treated with a PEBA regimen (cisplatin, etoposide, bleomycin, and adriamycin), supplemented by radiotherapy or surgery, from January 1988 to June 1992. A total of 80.8% of the patients had received at least four drugs, and 69.2% had received six or more cycles of combination chemotherapy. All of the patients were primarily treated with PEBA chemotherapy, 5 patients underwent hysterectomy, 9 patients received local lung and/or pelvis cobalt-60 irradiation, and 2 patients with brain metastases received whole brain irradiation. Twenty-five patients achieved a complete remission (CR 96.2%), but 7 patients relapsed. One patient with a relapse reentered sustained CR through surgery and further chemotherapy. Another patient who relapsed lives with tumor after local lung irradiation and chemotherapy. Nineteen patients (73.1%) were in sustained CR lasting at least 1 year. The side effects of the PEBA regimen were moderate and tolerable. We think that PEBA is an optimal regimen for the treatment of drug-resistant choriocarcinoma.

[Tibial island flap with intermuscular vessels in resurfacing the defect in tibial or ankle region]

Since June 1985, 13 extensive defects over lower tibial and the ankle have been covered with the tibial island flaps with intermuscular space vessels. Ten of the flaps survived completely. Partial necrosis of the flaps was found in 3 cases which healed spontaneously without further surgical intervention. The area of the flaps were from 42 to 200cm2, averaged 146cm2. Their rotation angles were from 90 to 180 degrees, averaged 128 degrees. The pedicle of the flap was the intermuscular cutaneous branches from the posterior tibial vessels. The procedure did no harm to the main trunk of the posterior tibial vessels, therefore, did not affect the peripheral circulation of the leg. The procedure is easy, practical and safe.

The reverse flow ulnar artery island flap: 42 clinical cases

Based on anatomical and dye injection observations, since 1984 42 cases of hand tissue defects (due to injury or surgery) have been reconstructed using a reverse flow unlar artery forearm island flap. Of the 42 cases, aetiology has included extensive crushing (25 cases), electric saw injuries (7 cases), burn scars (4 cases) and tissue defects following tumour or chronic ulcer resection (6 cases). Only one flap developed necrosis. The survival rate was 97.6%, including 4 cases of distal marginal necrosis. This procedure, therefore, offers a useful alternative in the repair and reconstruction of extensive tissue defects in the hand, whether caused by accidental injury or by surgery.

[Indication of extended radical operation for gastric antrum cancer assessed by rules of lymphatic metastasis]

Study on the lymphatic metastasis rule of 83 cases of gastric antrum carcinoma showed overall lymphatic metastasis rate (LMR) was 80.7% (67/83) and overall metastasis degree was 22.9% (i. e. 440 positive in the 1926 lymph nodes). There is no significant difference (P greater than 0.05) in LMR in the second line (N2) for the lesions with various biological features. Growth mode and histological type have the greatest influence on LMR in the third line (N3). N3 in the infiltration type and poorly or undifferentiated type is obviously higher than that in the localized and well-differentiated types (P less than 0.01). In view of the results, we conclude that extended radical operation (R3) should not be used as a routine operation for gastric cancer and be selectively carried out referring to the biological features of the tumor. In general, stage I gastric cancer is not indicated for R3; stages II and III are absolute indications; stage IV is the relative indication, i. e. group T1-4a N3M0 can be indicated; a part of T4b can also be treated by R3 resecting en bloc the involved organs but group M1 would miss the radical treatment. Besides, total gastrectomy or combined resection of spleen, body and tail of the pancreas should not be done routinely for gastric antrum cancer. They are to be performed according to the degree of involvement of the gastric body and metastasis in the lymph node groups 1, 2 and 3, 4.