The Zone of Conformity: A Comparison of Private and State-Controlled Enterprises in M&As

Drawing from the literature on institutional pressure, we argue that firms with different ownership types have different strategic options in domestic and overseas markets, namely the zone of conformity. State-controlled enterprises (SCEs) have a broader range of acceptable actions than do private-controlled enterprises (PCEs) in a domestic market but face more sanctions and stricter conformity requests in an overseas market. The concept of the zone of conformity predicts SCEs have a higher probability of deal failure overseas than in domestic markets and strategically seek less equity ownership of target firms in cross-border deals. The autocracy level of target country moderates the M&A behaviors difference between SCEs and PCEs. Our analysis of 12,497 Chinese mergers and acquisitions supports the study hypotheses.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11575-023-00501-9.

Governors' pro-market ideology as institutional enablement of firm internationalization

Purpose

Extant literature has indicated that government support is one of the main drivers of international expansion of Chinese multinational enterprises. However, research on the influence of governors on firm internationalization is still limited. Drawing upon the institution-based view, we theorize a novel concept of institutional enablement to illustrate the influence of a governor's pro-market ideology on Chinese firms' internationalization.

Design/methodology/approach

We analyze the relationship between a governor's pro-market ideology (consisting of a pro-market political ideology, an overseas educational background and a business background) and firm internationalization with a sample of Chinese public companies during 2014–2017.

Findings

We find a direct and positive effect of a governor's pro-market ideology on firm internationalization. We also find an indirect and positive effect of a governor's pro-market ideology through regional, inward foreign direct investment.

Originality/value

To the best of our knowledge, this paper is the first to investigate an underexplored question of the impact of governors on firm internationalization and to develop a novel concept of institutional enablement, based on discursive institutionalism.

[Curative effect observation of application of the snare in epiglottic cystectomy by arc-shaped laryngoscopy]

Objective:To evaluate the effect of the epiglottic cystectomy by arc-shaped video laryngoscopy combined with snare. Method:The clinical data of 42 patients with epiglottic cysts were retrospectively analyzed. Forty-two patients with epiglottis cyst were treated by arc-shaped video laryngoscopy combined with snare. Result:All 42 cases were completely resected at one time without obvious complications and the cure rate was 100%. Moreover, the short operation time（5-20 min） and the minor hemorrhage（1-10 ml） were observe. There was no recurrence after 6 to 33 months follow-up. Conclusion:The epiglottic cystectomy by arc-shaped video laryngoscopy combined with snare has the advantages of broad vision, easy operation, minimal invasion, rapid recovery and good curative effect, it is worthy to be popularized in clinical application.

[Relative factors of transmural intestinal necrosis in acute superior mesenteric vein thrombosis]

Objective: To examine the relative factors of transmural intestinal necrosis (TIN) during multidisciplinary stepwise management facilitating the decision making in patients with acute superior mesenteric vein thrombosis (ASMVT). Methods: Clinical data of patients with ASMVT admitted to Department of General Surgery, Jinling Hospital from January 2009 to June 2017 were reviewed retrospectively. There were 52 males and 37 females, aging (45.9 ± 12.6) years (range: 20 to 69 years). According to the postoperative pathological results and follow-up, the patients were divided into TIN group (n=31) and non-TIN group (n=58, including 18 cases of intestinal stricture). The related factors were compared between ASMVT patients with TIN and patients without TIN by univariate analysis using t test, U test and χ(2) test accordingly, and factors with statistically significance were subsequently submitted to binary Logistic regression analysis. The predictive value and cut-off point of factors were evaluated by receiver operator characteristic (ROC) curve and area under the curve. Results: In univariate analysis, smoking, hypertension, peritonitis, white blood cell count,haemoglobin, international normalized ratio, blood albumin, thrombosis of superior mesenteric branches vein, free intraperitoneal fluid, decrease of bowel wall enhancement and pneumatosis intestinalis were TIN risk factors (all P<0.05). According to the binary Logistic regression analysis, white blood cell count (OR=1.093, 95%CI: 1.010 to 1.182, P=0.027), thrombosis of the superior mesenteric branches vein (OR=11.519, 95%CI: 1.906 to 69.615, P=0.008), pneumatosis intestinalis (OR=11.140, 95%CI: 2.360 to 52.585, P=0.002) were independent relative factors of TIN in patients with AMI, and the area under the ROC curve of the above factors and predictive model was 0.759 (95%CI: 0.647 to 0.871), 0.745 (95%CI: 0.641 to 0.848), 0.737 (95%CI: 0.621 to 0.854), 0.909 (95%CI: 0.847 to 0.971), respectively. The cutoff value of white blood cell count was 18.1 × 10(9)/L. Conclusion: White blood cell levels, superior mesenteric vein branch thrombosis and pneumatosis intestinalis are independent predictors of TIN in ASMVT.

Application of Demirjian's and Cameriere's Method in Dental Age Estimation of 8-16 Year Old Adolescents from Hunan Han Nationality

Abstract

Objective To apply Demirjian's and Cameriere's method for dental age estimation of adolescents from Hunan Han nationality, and compare the accuracy of the two methods. Methods A total of 480 orthopantomograms of?8-16 year?old adolescents from Hunan Han nationality?with no special diseases and good nutritional status were collected?by Xiangya Stomatological Hospital of Central South University from January, 2016 to July, 2017, among them 236 males and 244 females. The dental age of each adolescent was determined by Demirjian's method and Cameriere's method, respectively, and the paired t-test of the estimated dental age and the chronological age determined by the two methods was conducted by SPSS 20.0 software to compare the difference between estimated dental age and chronological age. Results Mean chronological age of males and females was 11.91 and 11.88 years, respectively. The estimated dental age determined by Demirjian's method showed an underestimate of chronological age by an average of 0.11 years （males） and 0.15 years （females）, while the estimated dental age determined by Cameriere's method showed an underestimate of chronological age by an average of 0.83 years （males） and 0.72 years （females）. Conclusion Demirjian's method is more accurate than Cameriere's method in dental age estimation of adolescents from Hunan Han nationality, therefore more suitable for dental age estimation of adolescents in this region.

[The role of body fat rate in the evaluation of obstructive sleep apnea]

Objective: To investigate the role of body fat ratio in the evaluation of obstructive sleep apnea(OSA). Methods: A retrospective analysis was made on 174 cases (between November, 2017 and April, 2018 showed that) of sleep monitoring in the Department of Otorhinolaryngology in Peking University Third Hospital. The data included the gender, age, body fat rate, body mass index (BMI), neck circumference, and apnea-hypopnea index (AHI). The above data were analyzed by non parametric correlation analysis, receiver operating characterristic (ROC) curve analysis and multiple factor Logistic regression analysis to study the relationship between the gender,age,body fat rate,BMI,neck circumference and other indexes of the patients with AHI. Results: Nonparametric correlation analysis showed that the correlation from strong to weak to AHI among women was BMI (r=0.621, P<0.001),body fat rate (r=0.602, P<0.001), age (r=0.570, P<0.001), neck circumference (r=0.402, P=0.014), respectively. BMI (r=0.599, P<0.001), neck circumference (r=0.493, P<0.001), body fat rate (r=0.318, P<0.001), and age (r=0.256, P=0.003) among men. ROC curve analysis showed that the strong to weak index (area under curve,AUC) of the AHI>15/h among women was the body fat rate (AUC=0.884, P=0.001), BMI(AUC=0.810, P=0.008), neck circumference (AUC=0.759, P=0.027), age (AUC=0.750, P=0.033), and the male was BMI (AUC=0.765,P<0.001), neck circumference (AUC=0.720, P<0.001), age (AUC=0.634, P=0.008), and body fat rate (AUC=0.632, P=0.010), respectively. Multifactor Logistic regression analysis showed that the body fat rate (OR=1.704,95%CI=1.012-2.870) in women was an independent risk factor for AHI greater than 15/h; the age of male (OR=1. 044, 95%CI=1.005-1.085) and BMI (OR=1.285, 95%CI=1.056-1.562) were independent risk factors for AHI greater than 15/h. Conclusion: Body fat rate can be used as a new indicator for predicting the severity of OSA,especially in adult female population. In adult female moderate to severe OSA patients (AHI>15/h), compared with BMI,neck circumference and age,the body fat rate has the greatest correlation with AHI. Compared with BMI,neck circumference and age,the body fat rate has a decisive role in predicting moderate to severe OSA (AHI>15/h).

[Application of endoscope assisted curved laryngoscopy technique in transoral laryngopharyngeal minimally invasive surgery]

Objective: To explore the possibility of endoscope assisted curved laryngoscopy technique applied in transoral laryngopharyngeal minimally invasive surgery and evaluate the advantages of this technique. Methods: Eight patients with huge benign lesions in larynx and pharynx undergoing transoral microsurgery at Peking University Third Hospital between February 2016 and February 2017 were enrolled in this study.The diagnosis included cyst at the base of tongue in two patients, cysts in the epiglottis in two patients, hemangioma in two patients, multiple masses of the hypopharynx and amyloidosis in supraglottic area in one patient each.The time and exposure during surgery, occurrence rate of complication and conditions of following-up were recorded. Results: The mean time of surgery was 20 min, the exposure was satisfying.There was no obvious complication after surgery.No residual or recurrent lesion was observed after 1 to 12 months follow-up(mean time 4.5 months). Conclusion: The endoscope assisted curved laryngoscopy technique has advantages in shortening the time of surgery, improving exposure and reducing the rate of complication and recurrence.

[A cost-effectiveness analysis on universal infant rotavirus vaccination strategy in China]

OBJECTIVE

To evaluate the cost-effectiveness of current universal infant rotavirus vaccination strategy, in China.

METHODS

Through constructing decision tree-Markov model, we simulated rotavirus diarrhea associated cost and health outcome on those newborns in 2012 regarding different vaccination programs as: group with no vaccination, Rotavirus vaccination group and Rotateq vaccination group, respectively. We determined the optimal program, based on the comparison between incremental cost-effectiveness ratio (ICER) and China' s 2012 per capital gross domestic product (GDP).

RESULTS

Compared with non-vaccination group, the Rotavirus vaccination and Rotateq vaccination groups had to pay 3 760 Yuan and 7 578 Yuan (both less than 2012 GDP per capital) to avert one disability adjusted life years (DALY) loss, respectively. RESULTS from sensitivity analysis indicated that both results were robust. Compared with Rotavirus vaccination program, the Rotateq vaccination program had to pay extra 81 068 Yuan (between 1 and 3 times GDP per capital) to avert one DALY loss. Data from the sensitivity analysis indicated that the result was not robust.

CONCLUSION

From the perspective of health economics, both two-dose Rotarix vaccine and three-dose' s Rotateq vaccine programs were highly cost-effective, when compared to the non-vaccination program. It was appropriate to integrate rotavirus vaccine into the routine immunization program. Considering the large amount of extra cost that had to spend on Rotateq vaccination program, results from the sensitivity analysis showed that it was not robust. Rotateq vaccine required one more dose than the Rotarix vaccine, to be effective. However, it appeared more difficult to practice, suggesting that it was better to choose the Rotarix vaccine, at current stage.

Decreased expression of tumor suppressive miR-874 and its clinical significance in human osteosarcoma

Dysregulation of microRNAs (miRs) is associated with cancer development and progression and aberrant expression of miR-874 have been found in some types of cancer. However, the expression and function of miR-874 in osteosarcoma remain unclear. The aim of this study was to explore the effects of miR-874 in osteosarcoma tumorigenesis and development. The expression level of miR-874 was quantified by real-time reverse transcription-polymerase chain reaction (RT-PCR) in human osteosarcoma cell lines and tissues. Using a miR-874 mimic, cell proliferation and migration assays were performed in an osteosarcoma cell line and tumorigenicity was observed in vivo in order to determine the effects of miR-874 in osteosarcoma cell lines and tissues. MiR-874 was significantly downregulated in osteosarcoma cell lines and clinical specimens. Decreased miR-874 expression was significantly associated with large tumor size, distant metastasis, and advanced clinical stage, and was an independent predictor of poor survival. Overexpression of miR-874 inhibited cell proliferation, invasion and migration in vitro, promoted cell apoptosis in vitro, and suppressed tumorigenicity in vivo. These findings indicate that miR-874 may act as a tumor suppressor in osteosarcoma and could serve as a novel therapeutic agent for miR-based therapy.

First Report of Neocosmospora vasinfecta var. vasinfecta Causing Soybean Stem Rot in South Korea

In September 2010, stem rot symptoms were observed on soybean plants (cv. Daepungkong) growing in a field located at Daegu (35.52° N, 128.35° E), South Korea. The first noticeable symptoms, observed on the top leaves, were difficult to distinguish from those of sudden death syndrome (SDS). However, after splitting the stems of symptomatic plants, typical stem rot symptoms appeared as reddish-brown to dark-brown discoloration of the pith. Stem lesions extended 15 to 20 cm upward from the soil surface. To isolate the causal agent, sections of diseased stems were surface disinfected with 1% sodium hypochlorite, placed on potato dextrose agar (PDA) containing streptomycin sulfate, and incubated at 25°C with a 12-h light regime. Two isolates were obtained (SSLNV17 and SSLNV18). Mycelia were white and floccose. Conidia (4.5 to 11.2 × 2.2 to 3.4 μm) were cylindrical to oblong-ellipsoidal, hyaline, and one-celled. Both isolates produced abundant perithecia after 3 to 4 weeks. Perithecia (205 to 331 mm in diameter) were orange to red, globose and ostiolate, with a short neck (80 to 126 mm in diameter). Unitunicate asci (88.6 to 115.3 × 14.5 to 17.3 mm) were cylindrical to clavate, with a short stalk (6.0 to 9.5 × 5.0 to 6.8 mm), and eight spores. Ascospores (13.3 to 17.5 × 10.7 to 12.7 mm) were uniseriately arranged, globose to oval, one-celled, and hyaline to pale brown, with walls with a rugose ornamentation. These morphological features are consistent with those of Neocosmospora vasinfecta var. vasinfecta (1). The internal transcribed spacer (ITS) region, partial translation elongation factor 1-alpha (EF1-α), and β-tubulin genes of rDNA of the two isolates were sequenced using primers ITS4/ITS5 (GenBank Accession Nos. KF662732 and KF662733), EF1-728F/EF1-986R (KF758839 and KF758840), and Bt2a/Bt2b (KF771004 and KF771005), respectively. Sequences of the ITS region, EF1-α, and β-tubulin genes of both isolates showed 99% similarity with several reported N. vasinfecta strains by BLAST analysis. Both morphological and sequence analyses confirmed that the two isolates were N. vasinfecta var. vasinfecta. Pathogenicity tests of both isolates were performed on 15 three-week-old seedlings of soybean cv. Williams inoculated with a spore suspension containing 1.0 × 10⁶ spores/ml, using stem puncture inoculation procedure under controlled conditions (4). Control plants were inoculated in the same way with sterile water. The results were observed by splitting the stem longitudinally and checking for discoloration of the pith 4 to 5 weeks after inoculation. Reddish-brown to dark-brown discoloration was observed in the stem pith of inoculated plants, with occasional chlorosis of the leaves. Moreover, numerous orange-red perithecia were produced on the inoculated stems. However, no symptoms were visible on control plants. The pathogen was re-isolated from the diseased plants, confirming Koch's postulates. Neocosmospora stem rot of soybean was first discovered in Japan and since then it has been reported in the United States and China (2,3,4). To our knowledge, this is the first record of soybean stem rot caused by N. vasinfecta var. vasinfecta in Korea. Our report indicates that Neocosmospora stem rot is a new threat to soybean production in Korea. References: (1) P. F. Cannon and D. L. Hawksworth. Trans. Br. Mycol. Soc. 82:673, 1984. (2) Y. Gai et al. Plant Dis. 95:1031, 2011. (3) F. A. Gray et al. Plant Dis. 64:321, 1980. (4) D. V. Phillips. Phytopathology 62:612, 1972.

Optimization of Xhhh strain biodegradation with metal ions for pharmaceautical wastewater treatment

Effects of three ions, Mn2+, Cu2+ and Zn2+ on biological treatment of pharmaceutical wastewaterby a functional strain Xhhh were investigated. Through orthogonal tests, Cu2+ was determined to be the most important factor influencing Xhhh biodegradation performance. Biodegradation kinetic experiments demonstrated that with Cu+ concentration at about 200 mg l(-1), the maximum of specific growth rate and specific degradation rate were obtained to be 0.033 and 0.075 d(-1), respectively. The optimal levels of Mn2+ (5.00 mg I(-1)), Cu2+ (2.00 mg l(-1)) and Zn2+ (5.00 mg l(-1)) were achieved based on experimental results of their effects on the activities of manganese peroxidase and lignin peroxidase, and biodegradation kinetic parameters. Among three types of biodegradation kinetic models (Monod, Tessier and Contois), Tessier model was found most reasonable for kinetics description of Xhhh growth (R2 = 0.995) and pollutants degradation (R2 = 0.970) in the case of metals optimization. Both kinetics evaluation and experimental results demonstrated that optimization with the three metals made a great contribution to Xhhh growth and COD removal for pharmaceutical wastewater treatment.

Calcium/Poly(9,9-dioctylfluorene) Interaction: A Theoretical Study

The geometric and electronic structures of poly(9,9-dioctylfluorene) (PFO) oligomer interacting with Ca atoms were studied using Møller-Plesset perturbation theory. A weak interaction with little charge transfer and with a relatively long Ca-C distance (about 4.0 Angstrom) was found when only one Ca atom was attached to a PFO unit. However, when two Ca atoms were adsorbed at a PFO unit, a strong interaction with a shorter Ca-C distance (about 2.67 Angstrom) took place with considerable charge transfer from the Ca atom to the PFO, resulting in significant deformation in the backbone of the PFO oligomer. In the latter case, the frontier orbitals of the PFO were modified. However, the deformed PFO and its modified frontier orbitals could be recovered when oxygen was added, which is in good agreement with experimental observation.

Phase I study of rubitecan and gemcitabine in patients with advanced malignancies

BACKGROUND

Rubitecan (9-nitrocamptothecin, 9-NC, Orathecin) and gemcitabine have single-agent activity in pancreatic and ovarian carcinoma. We conducted a phase I trial to evaluate the maximum tolerated dose (MTD) and toxicities of this combination in advanced malignancies.

PATIENTS AND METHODS

Twenty-one patients with refractory or recurrent malignancies were enrolled in this dose escalation trial. Dose escalation proceeded from a starting level of rubitecan at 0.75 mg/m(2)/day administered orally on days 1-5 and 8-12 in combination with gemcitabine 1000 mg/m(2) administered intravenously on days 1 and 8 of a 21-day cycle.

RESULTS

The MTD was defined as rubitecan 1 mg/m(2) administered orally days 1-5 and 8-12, and gemcitabine 1000 mg/m(2) administered intravenously over 30 min days 1 and 8, given every 21 days. Dose-limiting toxicity was myelosuppression including neutropenia and thrombocytopenia. Other side effects included diarrhea, nausea, vomiting and fatigue. Five patients with stable disease were observed among 18 evaluable patients.

CONCLUSIONS

The recommended phase II dose is rubitecan 1 mg/m(2) given orally on days 1-5 and 8-12 in combination with gemcitabine 1000 mg/m(2) as a 30-min intravenous infusion on days 1 and 8 of a 21-day cycle.

Metastatic human hepatocellular carcinoma models in nude mice and cell line with metastatic potential

Metastatic human HCC model is needed for the studies on mechanism and interven tion of metastatic recurrence. By using orthotopic implantation of histologically intact tissues of 30 surgical specimens, a patient-like metastatic model of hu man HCC in nude mice (LCI-D20) and a low metastatic model of human HCC in nude mice (LCI-D35) have been established. All mice with transplanted LCI-D20 tumors exhibited extremely high metastatic ability including spontaneous metasta sis to liver, lungs, lymph nodes and peritoneal seeding. Remarkable difference was also found in expression of some of the invasiveness related genes and growth factors between the LCI-D20 and LCI-D35 tumors. PAI-1 increased gradually following tumor progression in LCI-D20 model, and correlated with tumor size and AFP level. Phasic expression of tissue intercellular adhesio nmolecule-1 in this model was also observed. Using corneal micropocket model, it was demonstrated that the vascular response induced by LCI-D20 tumor was stronger than that induced by LCI-D35 tumor. Similar report on metastatic human HCC model in nude mice and human HCC cell line with metastatic potential was rarely found in the literature. This LCI-D20 model has been widely used for the studies on intervention of metastasis, including anti-angiogenesis, antisense approach, metallopro teinase inhibitor, differentiation inducer, etc. It is concluded that the establ ishment of metastatic human HCC model in nude mice and human HCC cell line with metastatic potential will provide important models for the in vivo and in vitro study of HCC invasiveness, angiogenesis as well as intervention of HCC recurrence.

[Effect of shenmai injection on neurocyte apoptosis and change of cytoplasmic calcium]

OBJECTIVE

To study the neurocyte apoptosis and change of cytosolic free calcium induced by hypoxia/hypoglycemia culture in SH-SY5Y human neuroblastoma cells, and the effect of Shenmai Injection (SMI) on them.

METHODS

The neurocyte apoptosis rate was analysed quantitatively by flow cytometry and cytosolic calcium was determined by measuring mean fluorescent value with Fluo-3 flurometry.

RESULTS

Hypoxia/hypoglycemia could induce neurocyte apoptosis and increase the cytosolic calcium in SH-SY5Y cells. SMI could inhibit the SH-SY5Y cell apoptosis and lower the concentration of cytosolic free calcium.

CONCLUSION

Apoptosis is one of the death pattern of nerve cells. SMI could obviously reduce the hypoxia/hypoglycemia induced apoptosis and calcium overload, thus protect the neurocytes.

Experimental studies on immune-complex in situ type glomerulonephritis in rabbits treated with mai-luo-tong and natural indigo

By injection of C-BSA, immune-complex in situ type glomerulonephritis was duplicated in rabbits and treated with Mai-Luo-Tong and natural Indigo. The results showed that proteinuria in the treated groups M and Q was decreased. The difference between group M and control group is statistically significant (P < 0.05). Under light and electron microscope, although glomerular basement membrane was irregularly thickened and subepithelial dense electron deposited in the treated group, but microthrombus, erythrocytes and platelets aggregation and leukocytes impaction were not seen within glomerular capillaries. Also in groups C, Q, M, mesenteric cell count was 99.40 +/- 18.53, 92.87 +/- 17.89, 66.55 +/- 7.75 respectively, the M. Q groups are compared with group C, the result is of statistical significance (P < 0.05) and there is no apparent glomerular fibrosis in the treated groups.

Conformation therapy using a computer controlled telecobalt unit for advanced cervical carcinoma

This retrospective analysis evaluates the results of conformation radiotherapy for patients with advanced cervical carcinoma. Between January 1980 and September 1987, 16 patients with high common iliac/para-aortic node metastases from advanced carcinoma of the uterine cervix were treated using conformation radiotherapy. A large area from L1/L2 to the pelvis, with an average length of 23 cm, was treated to a total tumour dose of 5000-5500 cGy, with a daily tumour dose of 180-200 cGy in 28-30 daily fractions, using a computer controlled tracking cobalt unit (CCTCU). Before external beam irradiation, 11 patients underwent laparotomy/hysterectomy, seven were given chemotherapy and eight received brachytherapy. The preliminary results are encouraging. The actuarial 1-year, 3-year and 5-year survival rates after treatment were 81%, 44% and 37%, respectively. The locoregional control rate was 62.5%. None of the patients relapsed in the para-aortic nodes. All patients tolerated the large area of tracking irradiation therapy very well. None had any severe acute or delayed radiation complications. Use of the conformation radiotherapy technique to include the pelvic and para-aortic nodes has been shown to be an effective form of radiotherapy with minimal morbidity.

[Research on immune complex in situ type glomerulonephritis treated with mai-luo-tong in rabbits]

Applying c-BSA to duplicate immune complex in situ type glomerulonephritis in rabbits and treating it with Blood Circulation Promoting and Stasis-Removing Drugs Mai-Luo-Tong, the results showed that proteinuria in the treated group was decreased significantly, as compared to the control group (P < 0.01). Under light and electron microscope, although glomerular basement membrane was irregularly thickened and subepithelial dense electron deposits were found in both groups, but histopathologic damage in the treated group less than that of control one. In the treated group micro-thrombus, erythrocytes and platelets aggregation, leukocytes impaction were not seen within glomerular capillary. Also in the treated group mesangial cell proliferation and granulocyte infiltration were decreased significantly (P < 0.01) and there was no apparent glomerular fibrosis in former group.

Effect of low- and high-frequency TENS on Met-enkephalin-Arg-Phe and dynorphin A immunoreactivity in human lumbar CSF

Transcutaneous nerve stimulation (TENS) treatment was given for 30 min to 37 patients divided into 3 groups of 10 patients and 1 group of 7 patients. Two groups received low-frequency (2 Hz) and the other 2 groups high-frequency (100 Hz) stimulation. A diagnostic lumbar cerebrospinal fluid (CSF) sample was obtained immediately before and after stimulation. The CSF samples were subjected to analysis of immunoreactive (ir) opioid peptides, Met-enkephalin-Arg-Phe (MEAP) from preproenkephalin and dynorphin A (Dyn A) from preprodynorphin, respectively. Low frequency TENS applied on the hand and the leg resulted in a marked increase (367%, P less than 0.05) of ir-MEAP but not ir-Dyn A, whereas high-frequency (100 Hz) TENS produced a 49% increase in ir-Dyn A (P less than 0.01) but not ir-MEAP. This is the first report in humans that 2 Hz and 100 Hz peripheral stimulation induces differential release of peptides from preproenkephalin and preprodynorphin, respectively.

Electroacupuncture in rats: evidence for naloxone and naltrexone potentiation of analgesia

Low frequency electroacupuncture (EA) analgesia has been thought to be mediated by endogenous opioids. Among other lines of evidence, it has been reported that EA stimulation delivered at 2 and 2-15 Hz in rats could be blocked or partially antagonized by naloxone (NAL) and naltrexone (NTX). In contrast, experiments in one of our laboratories (D.J.M.) showed that NAL did not inhibit 2 Hz, and even potentiated 125 Hz EA analgesia. In an attempt to resolve these discrepancies, we conducted joint experiments in the U.S.A. and in China using the methods which previously yielded NAL reversibility of EA analgesia. In no experiment did opiate antagonists block or reduce EA analgesia. On the contrary, we found that, in most experiments, NAL and NTX potentiated 2 and 2-15 Hz EA analgesia respectively. The potentiation occurred independently of laboratory methods, geographic location of the experiment, strain (Chinese or American), tail temperature, sex, and weight of rats. This potentiation suggests the existence of an opioid anti-analgesic system or that NAL and NTX acquired analgesic properties following EA. These results indicate that EA analgesia in rats is a variable phenomenon even when laboratory methods are rigorously replicated. The EA stimulation may activate multiple conflicting neural circuits which interact and ultimately modulate the analgesic outcome.

[Disposition of 3-(N-piperidinomethylarino)methyl-rifamycin SV (FCE 22250) in rats]

After rats being given ig FCE 22250 5, 10 and 25 mg.kg-1, the plasma peak times (Tmax) were 12-14 h, the max plasma concentrations (Cmax) were 3.0, 5.6 and 12 micrograms.ml-1 respectively, and the half-lives of elimination (T1/2) were 24-26 h. The apparent volumes of distribution of the three doses were about 1 L.kg-1, suggesting that FCE 22250 in blood and in tissue was balanced. Total body clearance rate of each of the three doses was 29 ml.kg-1.h-1. The ig absolute bioavailability ranged from 69-84%. Its distribution in rats was as follows: the highest in liver, next in lung and then in fat, kidney, intestine, spleen, lymphaticode, heart, muscle, testis, the lowest in brain. It was eliminated mainly via the bile with feces. The human serum protein binding rate of FCE 22250 was 96.2%. It was shown that the rate was not correlated with drug concentration in serum under our experimental conditions.

The effect of volume of epidural morphine on postoperative analgesia in patients undergoing cesarean section

Ninety paturients undergoing elective cesarean section were included in this randomized study to compare the influence of the injected volume of epidural morphine (EM) on postoperative analgesia. Three similar groups of patients (n = 30 each) received 2 mg EM in 2 ml, 10 ml, and 20 ml saline respectively one hour after the last dose of 2% lidocaine. Pain scores (0-10) at rest (including uterine contraction pain) at the 2nd, 4th, 8th, 12th, 18th, and 24th h were compared among the three groups. There were no statistically significant differences of pain score among the three groups although lower pain score was present in the 20 ml group since the 8th h and thereafter. Regarding the number of patients who requested additional meperidine for pain relief 3 in 2 ml group, 2 in 10 ml group and 1 in 20 ml group respectively. The result may suggest that the influence of the injected volume of EM on postcesarean analgesia is not obvious.

[The role of selective bronchial arterial infusion in the comprehensive treatment of advanced bronchial carcinoma]

Bronchial arterial infusion (BAI) of cisplatinum and procaine was performed in 20 patients with confirmed, advanced bronchogenic cancer. The short-term response to BAI and survival period were reported. The responsive rates of CR and PR are 65% (75% in small cell carcinoma and 65% in squamous cell carcinoma). The overall mean survival period is 11.5 months (8 months in small cell carcinoma and 12 months in squamous cell carcinoma). We would like to point out that the comprehensive treatment based on BAI should be emphasized in order to improve the survival period. BAI followed by radiation therapy have an effect on completing each other in the therapy of squamous cell carcinoma. But, BAI should take the second place in treatment of small cell carcinoma.

[High and low frequency electroacupuncture analgesia are mediated by different types of opioid receptors at spinal level: a cross tolerance study]

Previous studies have shown that rats subjected to low or high frequency electroacupuncture (EA) stimulation release enkephalins or dynorphins respectively to produce analgesia. This conclusion was tested in the present study by using cross tolerance technique for further analysing their receptor mechanisms. The main results were as follows: (1) In rats subjected to 2 Hz EA for 6 h, there was a gradual decrease in the analgesic effect, leading to a state of tolerance to 2 Hz EA analgesia. These rats, however, still responded to 100 Hz EA. Likewise, rats made tolerant to 100 Hz EA were still effective to 2 Hz EA stimulation, showing not significant cross tolerance between 2 Hz and 100 Hz EA analgesia. (2) Rats made-tolerant to 100 Hz EA analgesia showed a diminished response to intrathecal dynorphin A (1-13), a kappa agonist, whereas the analgesic effect of the delta agonist [D-Pen2, D-pen5] enkephalin (DPDPE) remained intact. (3) Rats made tolerant to 2 Hz EA analgesia showed a cross tolerance to DPDPE, but not to dynorphin A (1-13). Results obtained from aforementioned cross tolerance studies suggest that 2 Hz and 100 Hz EA analgesia are mediated by delta and kappa opioid receptors, respectively, at the spinal cord of the rat.

Detection of small cell lung cancer bone marrow involvement by discontinuous gradient sedimentation

Marrow involvement by small cell lung cancer (SCLC) is detected in 10-23% of patients at initial diagnosis by marrow aspirate and biopsy techniques. To improve the detection and potentially monitor marrow involvement by SCLC we have attempted to concentrate malignant cells with clonogenic potential on a discontinuous density gradient (DDG). The bone marrow from 43 patients with SCLC (36 with histologically negative marrow aspirates and biopsies) were separated on a Ficoll-based DDG. Samples were also separated by conventional Ficoll-diatrizoate (FD) (density, 1.077) gradient sedimentation. The cellular interphase from three fractions (F X) corresponding to specific densities 1.050 (F X 1), 1.055 (F X 2), and 1.060 (F X 3) as well as cells separated by Ficoll-diatrizoate (F X FD) centrifugation were isolated and 2.5 X 10(5) cells from each fraction were cultured in 2 ml of 0.3% agar in McCoy's media with 10% fetal calf serum, 2.5 micrograms transferrin, 1 microgram insulin, and 1% penicillin-streptomycin. Colony growth was assessed after 14 days of culture at 37 degrees C and 6% CO2. Tumor colony growth was seen in eight of 36 (22%) patients with histologically negative marrows as well as in four of seven (57%) patients with known involvement. Mean colony growth per 2.5 X 10(5) cells for all 12 patients was 4.3 colonies for F X 1; 8.8 for F X 2; and 2.7 for F X 3. In contrast mean growth from the F X FD was 1.0 colonies. Cells with clonogenic potential could be demonstrated from F X 2 and F X 3 in seven of 12 and eight of 12 patients, respectively; in F X FD four of 12 patients had tumor growth. We conclude that separation of marrow samples by DDG concentrates malignant cells with clonogenic potential at least 8-fold compared to FD separation and that the sensitivity of the clonogenic assay in detecting marrow involvement by SCLC is enhanced by DDG sedimentation.