Role of Mxi1 in ageing organ systems and the regulation of normal and neoplastic growth

Mxi1 belongs to the Mad (Mxi1) family of proteins, which function as potent antagonists of Myc oncoproteins. This antagonism relates partly to their ability to compete with Myc for the protein Max and for consensus DNA binding sites and to recruit transcriptional co-repressors. Mad(Mxi1) proteins have been suggested to be essential in cellular growth control and/or in the induction and maintenance of the differentiated state. Consistent with these roles, mxi1 may be the tumour-suppressor gene that resides at region 24-26 of the long arm of chromosome 10. This region is a cancer hotspot, and mutations here may be involved in several cancers, including prostate adenocarcinoma. Here we show that mice lacking Mxi1 exhibit progressive, multisystem abnormalities. These mice also show increased susceptibility to tumorigenesis either following carcinogen treatment or when also deficient in Ink4a. This cancer-prone phenotype may correlate with the enhanced ability of several mxi1-deficient cell types, including prostatic epithelium, to proliferate. Our results show that Mxi1 is involved in the homeostasis of differentiated organ systems, acts as a tumour suppressor in vivo, and engages the Myc network in a functionally relevant manner.

[Determination of linear sintering shrinkage rate of slip-casting infiltrated ceramic]

This study tested the linear sintering shrinkage (SS) rate of ceramic infiltrated with different glasses (Vita In-ceram, G I-I La, G I-II La, G I-II Ce), the results showed that the linear SS rate was 0.08%-0.32%, which occurred mainly in the firing stage of alumina (P < 0.05) and glass infiltration had no influences on the dimensional stability of ceramic(P > 0.05). It suggests that the effects of glass infiltration on the dimensional stability of GI glasses were comparable with that of Vita In-ceram.

Alveolar macrophage response to remote organ injury

Intestinal reperfusion (IR)-induced pulmonary edema has been related to endogenous pulmonary thromboxane A2 (TxA2) release. This study examines the hypothesis that alveolar macrophages (aMphis) activated during IR are an important cellular source of TxA2 in this model. Anesthetized Sprague Dawley rats underwent 120 min of intestinal ischemia and 60 min of reperfusion (IR) or sham operation (Sham). aMphis were isolated by bronchoalveolar lavage and incubated in Krebs buffer for 30 min, after which the supernatant was analyzed for TxB2 (metabolite of TxA2) and prostaglandin E2. Other parameters of aMphi activation measured included lysosomal enzyme release (beta-glucuronidase), superoxide (O2-) release, and procoagulant activity. aMphis from animals sustaining IR generated more than twice as much TxA2 and prostaglandin E2 as did those isolated from controls (p < .05). Other evidence of aMphi activation included a nearly 100-fold increase in procoagulant activity, a 7-fold increase in beta-glucuronidase release, and a 2.5-fold increase in O2- release over that of controls (p < .05). These data suggest that TxA2 is a major eicosanoid product of aMphis during IR and that aMphis may be an important cellular participant in IR-induced pulmonary microvascular injury, either directly by releasing O2-, lysosomal enzymes, and pro-coagulant factors, or indirectly by generating TxA2.

[Minor alkaloids from the capsule of Papaver nudicaule L]

Two minor alkaloids were isolated from the capsule of Papaver nudicaule. On the basis of physicochemical methods and spectroscopic analysis, they were identified as chelidonine, 5-hydroxy-2-hydroxymethylpyridine. Chelidonine was isolated from this plant and 5-hydroxy-2-hydroxymethylpyridine was isolated from genus for the first time.

Thromboxane A2 mediates increased pulmonary microvascular permeability after intestinal reperfusion

This study examines the hypothesis that intestinal reperfusion (IR)-induced pulmonary thromboxane A2 (TxA2) release increases local microvascular permeability and induces pulmonary vasoconstriction. Sprague-Dawley rats underwent 120 min of intestinal ischemia and 60 min of IR. Sham-operated animals (Sham) served as controls. After IR or Sham, the pulmonary vessels were cannulated, and the lungs were perfused in vitro with Krebs buffer. Microvascular permeability was quantitated by determining the filtration coefficient (Kf), and pulmonary arterial (Ppa), venous (Ppv), and capillary (Ppc) pressures were measured to calculate vascular resistance (Rt). After baseline measurements, imidazole (TxA2 synthase inhibitor) or SQ-29,548 (TxA2-receptor antagonist) was added to the perfusate; then Kf, Ppa, Ppv, and Ppc were again measured. The Kf of lungs from IR animals was four times greater than that of Sham (P = 0.001), and Rt was 63% greater in the injured group (P = 0.01). Pc of IR lungs was twice that of controls (5.4 +/- 1.0 vs. 2.83 +/- 0.3 mmHg. IR vs. Sham, respectively; P < 0.05). Imidazole or SQ-29,548 returned Kf to baseline measurements (P < 0.05) and reduced Rt by 23 and 17%, respectively (P < 0.05). IR-induced increases in Pc were only slightly reduced by 500 micrograms/ml imidazole (14%; P = 0.05) but unaffected by lower doses of imidazole (5 or 50 micrograms/ml) or SQ-29,548. These data suggest that IR-induced pulmonary edema is caused by both increased microvascular permeability and increased hydrostatic pressure and that these changes are due, at least in part, to the ongoing release of TxA2.

Pharmacological potency and biodisposition of phencyclidine via inhalation exposure in mice

The purpose of the present study was to characterize the pharmacological effects and biodisposition of phencyclidine (PCP) following inhalation exposure to mice. Results from these studies indicate that PCP was easily volatilized when heated in a glass pipe. Volatilization was efficient with no significant formation of pyrolytic products. Exposure to the volatilized PCP resulted in a dose-dependent impairment in motor performance in both the rotorod and inverted-screen tests. PCP was equally effective in disrupting performance on the inverted-screen and rotorod with ED50 values corresponding to the volatilization of 10.7 and 13.2 mumol, respectively. The time courses were comparable to those produced following intravenous (i.v.) administration of PCP. In order to determine the dose of drug absorbed by inhalation, mice were exposed to [3H]-PCP. The ED50 values of PCP following i.v. administration were 4.1 and 6.2 mumol/kg in the inverted screen and rotorod, respectively. The biodisposition of PCP following inhalation exposure was similar to that after i.v. injections. At doses that produced approximately 50% of the maximum motor impairment by either administration route, higher ratios of the total drug equivalents were found following i.v. injection than that after inhalation, with the brain/plasma ratios of 1.3 +/- 0.2 versus 0.58 +/- 0.02, and brain/body ratios 0.59 +/- 0.06 versus 0.35 +/- 0.1 for i.v. and inhalation, respectively. However, the brain/plasma ratios of the concentrations of PCP were similar, 1.1 versus 0.9. The body concentration of PCP equivalents that produced 50% of the maximum effect after inhalation was 4.7 +/- 0.6 mumol/kg. These results indicate that inhalation of PCP produces a similar pharmacological profile to that of i.v. administration and suggest that the drug is equipotent by these two administrations routes. Moreover, these findings are consistent with the observation that smoking is becoming the most common route of administration among drug users.

[A pathological study on phenotype differentiation and its significance in pulmonary large cell carcinoma]

This study was designed to find the differentiated phenotype and its clinicopathological significance in pulmonary large cell carcinoam (PLCC) by immunohistochemical methods using a panel of antibodies related to the phenotype differentiation: high molecular weight cytokeratin, low molecular weight cytokeratiin, secretory component, chromogranin A and synaptophysin in 60 cases of PLCC. The results demonstrated that all cases of PLCC possessed monophasic, biphasic and triphasic phenotype differentiation features respectively, including squamous (4 cases), adenomatous (20 cases), neuroendocrine (19 cases), adenosquamous (11 cases); and the the coexistence of adenomatous, squamous and neuroendocrine (6 cases). The median survival time was different between patients with various differentiated phenotypes of PLCC. There was a statistically significant difference (P < 0.05) in survival between neuroendocrine and adenomatous phenotypes. The results of this study implies that: (1) PLCC expressed different phenotypes of differentiation, (2) phenotypes of neuroendocrine differentiation has a poor prognosis, (3) it is necessary to classify PLCC according to the phenotype differentiation.

Inhalation exposure to volatilized opioids produces antinociception in mice

The goal of this study was to determine whether opioids of varying potencies are pharmacologically active via the inhalation route of administration in mice. The opioids evaluated included heroin, morphine, codeine, fentanyl and meperidine; each of these drugs has the potential for abuse in humans. Inhalation exposure to each of these compounds produced antinociception in a dose-dependent manner as assessed in the tall-flick test. No pyrolysis products were detected after heating either morphine or codeine at 250 degrees C for 5 min. Although 6-acetylmorphine was found after heating heroin, it accounted for less than 5% of the recovered sample. Heroin was somewhat less potent by inhalation administration than i.v. injection, with ED50 values of 1.6 and 0.69 mumol/kg, respectively. In contrast, the relative potency of morphine was substantially greater when inhaled than when injected, with respective ED50 values of 0.77 and 3.9 mumol/kg. Whereas the body to brain ratios of [3H]morphine were approximately 8 and 20 for inhalation exposure and i.v. injection, respectively, the ratio for heroin was approximately 5 regardless of administration route. This pattern of results suggests that the increase in morphine potency upon inhalation may have resulted from an increased accessibility to the brain compared with i.v. injection. Finally, naloxone reversed the antinociceptive effects of volatilized heroin, but neither the kappa selective antagonist nor-binaltorphimine nor the delta selective antagonist naltrindole blocked this antinociception, which suggests the involvement of mu opioid receptors. These findings taken together suggest the potential for the abuse of a variety of opioids, in addition to heroin, through the inhalation route of administration by humans.

[A study on p53 gene mutation, protein expression and relationship with clinico-pathological status in large cell carcinoma of the lung]

Immunohistochemistry and in situ hybridization techniques were used to investigate the correlation between p53 gene mutation and the clinico-pathological status as well as prognosis of large cell carcinoma of the lung. p53 expression was found in 40% of the cases by immunohistochemistry and p53 gene mutation was found in 53.3% by in situ hybridization. The concordance ratio was 73.3% between gene mutation and protein expression. No statistically significant correlation was found between p53 gene mutation, its protein expression and sex, age, smoking, histological type, tumor size or lymph node involvement. A significant correlation was found between p53 gene mutation (or its protein expression) and mitotic index. The result of in situ hybridization demonstrated that there was a statistically significant correlation between p53 gene mutation and a poor prognosis. It was found that p53 gene mutation was associated with fast growth of the tumor. Therefore p53 gene mutation is probably an indicator of poor prognosis for large cell carcinoma of the lung.

Estrogen increases male rat aortic endothelial cell (RAEC) PGI2 release

Estrogen has been proposed as a negative risk factor for development of peripheral vascular disease yet mechanisms of this protection are not known. This study examines the hypothesis that estrogen stimulates rat aortic endothelial cell (RAEC) release of PGI2. Male Sprague-Dawley rat abdominal aortic 1-mm rings were placed on 35 mm matrigel plates, and incubated for 1 week. The cells were transferred to a Primaria 60-mm dish and maintained from passage 3 in RAEC complete media and experiments performed between passages 4-10. Cells were incubated with Krebs-Henseleit buffer (pH 7.4) containing carrier or increasing concentrations of beta-estradiol or testosterone for 60 min. The effluent was analyzed for eicosanoid release of 6-keto-PGF1 alpha (6-keto, PGI2 metabolite), PGE2 and thromboxane B2 (TXB2) by EIA (hormone stimulated-basal). Cells were analyzed for total protein by the Bradford method and for cyclooxygenase-1 (COX-1) and prostacyclin synthase (PS) content by Western blot analysis and densitometry. Testosterone did not alter RAEC 6-keto-PGF1 alpha release, whereas estrogen increased RAEC 6-keto-PGF1 alpha release in a dose-related manner. Estrogen preincubation (10 ng/ml) decreased COX-1 and PS content by 40% suggesting that the estrogen-induced increase in male RAEC PGI2 release was not due to increased synthesis of COX-1 or PS. These data support the hypothesis that estrogen stimulation can increase endogenous male RAEC release of PGI2.

Loss of transcriptional attenuation in N-myc is associated with progression towards a more malignant phenotype

The modulation of RNA polymerase II processivity through the untranslated N-myc first exon represents an important mechanism governing N-myc mRNA levels during normal development. In this study, we employed the rat embryo fibroblast (REF) cooperation assay as a functional means to (i) map N-myc first exon sequences involved in the regulation of N-myc gene expression and specifically their contribution to controlling a block to transcriptional elongation and (ii) determine whether this transcriptional control mechanism plays a role in governing the oncogenic activity of N-myc. Transfection of N-myc expression constructs harboring various deletions within the untranslated first exon revealed that a region encoding a potential stem-loop structure followed by a thymine stretch (stem-loop/T region) was required for efficient transcriptional attenuation. The increase in transcriptional read-through associated with all deletions involving the stem-loop/T region also resulted in a more aggressive malignant phenotype as evidenced by a significant enhancement in the subcloning efficiency of N-myc/ras transformed foci. Most significantly, when cell lines generated from overexpression of the intact N-myc expression construct were selected for anchorage-independent growth, a strong block to transcriptional elongation was completely eliminated in all cases examined. Since the subcloning efficiency of transformed foci and the capacity of permanently established cell lines for anchorage-independent growth are direct correlates of more advanced stages of malignant transformation, our findings suggest that loss of transcriptional attenuation represents an important genetic event in the progression of N-myc-induced cellular transformation.

Determination of the protein components of native thin filaments isolated from natural actomyosin: nebulin and alpha-actinin are associated with actin filaments

A new method was developed for extracting natural actomyosin with full length connectin (titin) and nebulin from rabbit skeletal muscle. To determine the protein components of native thin filaments, thin filaments were isolated from natural actomyosin by sedimentation in a H2O/D2O/sucrose density gradient. Both alpha-actinin and nebulin were cosedimented with actin filaments, while connectin was not. This shows that the native thin filaments contained alpha-actinin and nebulin. This indicates that the native thin filaments were more complicated than synthetic filaments reconstituted from actin, tropomyosin, and troponin. It is known that synthetic filaments are less Ca2+ sensitive than native thin filaments. This difference in Ca2+ sensitivity may be due to the differences in components and/or the different structures of native and synthetic filaments. The newly developed methods described here for extracting natural actomyosin and for isolating native thin filaments are useful for addressing these important problems related to the structure and function of native thin filaments.

[Study of autologous bone marrow transplantation in the treatment of gynecologic carcinoma]

OBJECTIVE

To investigate the role of autologous bone marrow transplantation (ABMT) in patients with gynecologic carcinoma treated by high-dose chemotherapy.

METHODS

This was a presentation of four patients with ovarian carcinoma, two patients with primary fallopian tubal carcinoma, and 5/6 of them clinically staged as III and IV, treated with combination chemotherapy of cytoxan and carboplatin by intraperitoneal and intravenous infusion, the dose being 2.5-5 times those employed conventionaly. Autologous bone marrow collection and storage were conducted under strictly sterile conditions. Chemotherapy was given pre- and post-operatively and ABMT was performed immediately after chemotherapy. Careful follow-up was observed at monthly intervals.

RESULTS

All of the six patients tolerated the treatment well, with no death within a median follow-up of 26 months (range 1532). Five of them lived more than 6 months with no evidence of disease. Two patients without gross residual tumor, who could not tolerate conventional chemotherapy which had to be discontinued, successfully received high-dose chemotherapy, supported by ABMT. All four patients with gross residual tumor benefited by immediate clinical remission after treatment. Median survival for all patients was 28 months (range 1253), median survival for stage IV patients was 24 months (range 1230).

CONCLUSIONS

Patients subjected to high-dose chemotherapy supported by ABMT are exempted from suffering the cyclic multiple courses of chemotherapy, repeated or long-term hospitalization and may lead a life of good quality.

[A study on stretching capacity of continuous circular capsulorhexis and nucleus delivery]

The stretching capacity of continuous circular capsulorhexis (CCC) in 20 human cadaver eyes was determined. The increases in circumference of the tear opening ranged from 164. 5% to 190.9% and that in area of the opening ranged from 235.2% to 364.6%. If a proper technique of capsulorhexis is adopted, the nucleus of 7-9.5 mm in diameter and 3-4.5mm in thickness can be delivered through a CCC opening of 4-6mm in diameter by hydrodissection and hydroexpression of nucleus without capsular tear.

IFN-gamma-dependent IL-7 gene regulation in keratinocytes

IL-7 plays a central role in regulating the growth and differentiation of T cells. We have reported previously that epidermal keratinocytes produce biologically relevant amounts of IL-7, thereby supporting the growth of epidermal gamma delta T cells. In this report, we report that IL-7 gene expression is regulated in keratinocytes by IFN-gamma. Treatment of Pam 212 keratinocytes with IFN-gamma induced a preferential expression of 2.6- and 1.5-kb IL-7 mRNAs, in addition to the 2.9- and 1.7-kb mRNAs that are expressed constitutively. The 2.6- and 1.5-kb mRNAs are produced through the use of alternative transcription initiation sites; these mRNAs are transcribed within 250 bp from the coding sequence, whereas 2.9- and 1.7-kb mRNAs contain > 400 bases in the 5'-untranslated region. IFN-gamma appears to promote this conversion through the IFN-stimulated response element (ISRE), which is located 270 bp upstream from the coding sequence. ISRE is followed by the initiator, a non-TATA-type transcription control element. Functional relevance of the ISRE/initiator complex was suggested by the observations that IFN-gamma-dependent transcription was initiated from immediately downstream of this complex, and that its deletion resulted in an abrogated IFN-gamma responsiveness in transcriptional regulation. These results document a novel mechanism by which IL-7 gene expression is regulated in keratinocytes by a cytokine produced by T cells (IFN-gamma).

IFN-gamma-dependent IL-7 gene regulation in keratinocytes

IL-7 plays a central role in regulating the growth and differentiation of T cells. We have reported previously that epidermal keratinocytes produce biologically relevant amounts of IL-7, thereby supporting the growth of epidermal gamma delta T cells. In this report, we report that IL-7 gene expression is regulated in keratinocytes by IFN-gamma. Treatment of Pam 212 keratinocytes with IFN-gamma induced a preferential expression of 2.6- and 1.5-kb IL-7 mRNAs, in addition to the 2.9- and 1.7-kb mRNAs that are expressed constitutively. The 2.6- and 1.5-kb mRNAs are produced through the use of alternative transcription initiation sites; these mRNAs are transcribed within 250 bp from the coding sequence, whereas 2.9- and 1.7-kb mRNAs contain &gt; 400 bases in the 5'-untranslated region. IFN-gamma appears to promote this conversion through the IFN-stimulated response element (ISRE), which is located 270 bp upstream from the coding sequence. ISRE is followed by the initiator, a non-TATA-type transcription control element. Functional relevance of the ISRE/initiator complex was suggested by the observations that IFN-gamma-dependent transcription was initiated from immediately downstream of this complex, and that its deletion resulted in an abrogated IFN-gamma responsiveness in transcriptional regulation. These results document a novel mechanism by which IL-7 gene expression is regulated in keratinocytes by a cytokine produced by T cells (IFN-gamma).

[Pharmacokinetics study of intraperitoneal carboplatin in gynecologic carcinoma]

Twenty patients with surgically and pathologically confirmed gynecologic cancer from December, 1991 to December, 1992 were treated by intraperitoneal (i.p.) chemotherapy with carboplatin in 15 and by intravenous (i.v.) chemotherapy with carboplatin in 5, patients had normal hepatic and renal function test and were nonsmoker. Using Grathite atomic absorption spectrum method, total mean maximal plasmic carboplatin concentration in the cases by intravenous infusion was 8 times greater than those by intraperitoneal infusion. The half-life of plasmic elimination in the cases treated by i.v. infusion and by i.p. infusion were respectively 10.82 +/- 4.95 hours and 54.04 +/- 10.75 hours (P < 0.05). But total carboplatin plasmic clearance in the cases were 1.88 +/- 0.53 ml/min and 1.12 +/- 0.58 ml/min, respectively (P < 0.05). Pharmacokinetic profiles suggest a possible therapeutic advantage by giving the drug intraperitoneally for the treatment of tumour nodules situated in the peritoneum. This research also suggest the method has the possibility in increasing antitumn effect and decreasing bone marrow in intoxication because of the wide distribution, low plasmic concentration and slow clearance of drugs.

[An orthogonal method for comparing extracting techniques of licorice root extract]

A L9(3(4)) form developed by the orthogonal method was used to study the size, extraction solvent and extraction frequency of licorice root extract, and taking the recovery of glycyrrhizic acid as the criteria, a comparison was made on the different ways of extracting the herb. The result showed the glycyrrhizic acid could be recovered over 10% (about 7% higher than that from water treatment) when the herb was cut into pieces and then extracted by fluxing for 3 times with 60% alcohol containing 0.3% ammonia.

Dynorphin A-(1-13)-morphine interactions: quantitative and qualitative EEG properties differ in morphine-naive vs. morphine-tolerant rats

The effects of dynorphin A-(1-13) on cumulative IV morphine-induced EEG and EEG power spectra were studied in naive and morphine-tolerant rats. Adult female Sprague-Dawley rats were implanted with cortical EEG electrodes and permanent indwelling ICV and IV cannulae. In naive rats, dynorphin A-(1-13) quantitatively decreased cumulative IV morphine-induced EEG spectral power as well as qualitatively shifting the relative distribution of spectral power to predominantly faster frequencies. In morphine-tolerant rats, the quantitative and qualitative EEG properties were identical to those in dynorphin A-(1-13) pretreated morphine-naive rats. Thus, dynorphin A-(1-13) pretreatment apparently produced instantaneous acute morphine tolerance. Furthermore, in morphine-tolerant rats, dynorphin A-(1-13) pretreatment quantitatively increased morphine-induced EEG power without qualitatively changing the relative distribution of EEG spectral power. This latter effect may be due to a summation of increased endogenous levels of dynorphin A-(1-13) associated with the development of morphine tolerance and the experimentally administered dynorphin A-(1-13). These results indicate that dynorphin-induced quantitative and qualitative EEG changes of morphine may reflect different underlying processes. That is, quantitative changes may reflect the number of receptors that are activated, while qualitative changes may reflect the nature of the receptor-effector coupling.

Requirement of cellular uptake for adenosine inhibition of p-nitrophenol glucuronidation in isolated rat hepatocytes

Adenosine (ADO) has been shown previously to inhibit p-nitrophenol glucuronidation in a concentration-dependent manner when concurrently incubated in isolated rat hepatocytes for 30-60 min. In the current study, preincubation of ADO (500 microM) in isolated hepatocytes for 30 min prior to addition of 100 microM p-nitrophenol resulted in a greater inhibition of glucuronidation when compared to that without preincubation (80 vs 50% inhibition). The inhibitory effect of 250 microM ADO on glucuronidation was decreased from 60 to 10% in the presence of the ADO transport inhibitor nitrobenzyl thioinosine during the 30-min preincubation period. Without prior incubation, 100 microM dibutyryl cyclic AMP (DBcAMP) produced an inhibition of glucuronidation similar to that of 500 microM ADO. In contrast to ADO, there was no significant difference in the inhibitory effect of DBcAMP on p-nitrophenol glucuronidation with or without a 30-min preincubation. Thus, DBcAMP and ADO appear to inhibit glucuronidation through different mechanisms. Furthermore, these results indicate that the inhibitory effect of ADO on p-nitrophenol glucuronidation is dependent to a large degree on the cellular uptake of ADO into hepatocytes, while a portion of the inhibitory effect may arise from the generation of intracellular cyclic AMP.

Jaw movements and EMG activities of limb-licking behavior during grooming in rabbits

Jaw movements and masticatory muscle activity were recorded in freely moving rabbits during limb-licking, chewing, and drinking. The limb-licking movement was characterized by rhythmical jaw movement and digastric burst and relatively small masseter activity. The mean cycle time was 292 ms +/- 11.0 (mean +/- SE: n = 7) and was longer than that in chewing (267 ms +/- 20.8, p < 0.01) or drinking (208 ms +/- 15.2, p < 0.01). Jaw movements in the frontal plane of the ingestive behaviors coincided with those reported in previous studies; however, that of the licking movements was featured here. The basic cycle included; a) an opening stroke in which the mandible moved downward and laterally, b) a lateral excursion stroke in which the mandible moved medially and either upward or downward, and c) a closing stroke in which the mandible moved upward to the closing position. During opening, the digastric activity on the working side was determined to be larger than that on the other side (p < 0.001).

Introduction of the ras oncogene transforms a simian virus 40-immortalized hepatocyte cell line without loss of expression of albumin and other liver-specific genes

Activated c-Ha-ras DNA sequences were introduced by transfection into a low passage simian virus 40 (SV40)-immortalized rat hepatocyte cell line, CWSV1, and stable ras transfectant cell lines were established to determine the effect of the addition of the activated c-Ha-ras oncogene on growth properties and differentiation. Control transfectant cell lines were generated by transfection with neo alone. CWSV1 cells at low passage and the control transfectants were not tumorigenic. The ras transfectants demonstrated anchorage-independent growth and were highly tumorigenic in syngeneic hosts. CWSV1 cells produce liver-like levels of albumin and express other liver-specific genes. The ras transfectants expressed RNA for albumin, transferrin, and the transcription factor HNF-1 at similar levels to the parental CWSV1 cells, indicating that the alterations in growth properties and tumorigenic potential of these cells did not decrease the ability of the cells to express several genes that are associated with hepatocyte differentiation. The addition of the ras oncogene did not induce the expression of alpha-fetoprotein and had no specific effect on expression of glutathione S-transferase-P. The tumors produced by the ras transfectants were not well differentiated; however, the cells in the tumors and tumor cell lines derived from the tumors continued to produce albumin and did not produce alpha-fetoprotein. We conclude that the addition of the activated c-Ha-ras oncogene to immortalized CWSV1 cells transformed these cells as measured by morphology, growth properties, and tumorigenicity without reducing their ability to express albumin and other significant liver-specific genes.

[Anatomy and microstructure of the disco-malleolar ligament]

The disco-malleolar ligament was studied with the method of the anatomy and histology, and it's function was observed in the living people. It was found that the ligament takes its origin from the neck and anterior process of the malleus in middle ear and inserts into the capsule and meniscus of the temporomandibular joint. Part of the fibers was mixed with the spheno-mandibular ligament and attaches on the lingula of the mandible. The disco-malleolar ligament consists of collagenous fibers and elastic fibers. A peri-ligamentous space exists between the ligament and bone tissue. It was found the tympani membrana light cone area became smaller in opening position and larger in closing position. The existing peri-ligamentous space of the disco-malleolar ligament is a latent way between temporomandibular joint rear and tympanum.

p-Fluoro-hexahydro-sila-difenidol exhibits poor selectivity between M3 and M1 muscarinic receptors

We investigated the potential ability of p-fluoro-hexahydro-sila-difenidol (p-F-HHSiD) to discriminate between M1 and M3 muscarinic receptor subtypes using Chinese hamster ovary cells stably transfected with the genes encoding the two receptors. Both radioligand binding and functional assays were utilized for this purpose. In contrast to initial reports of a 14-fold selectivity of this antagonist for M3 versus M1 receptors, we have detected a qualitatively similar selectivity that was markedly smaller in magnitude.

[Chemical constituents of Agapetes obouata S. H. Huong]

Six compounds were isolated from Agapetes obouata. On the basis of physico-chemical constants and spectral analysis they were identified as friedelin (I), fernenal (II), beta-sitosterol (III), daucosterol (IV), beta-sitosterol glucutonide (V) and n-tridecane (VI) respectively.

Cancer in the gastric remnant in China--a review of 33 cases in China

A review of 33 cases of cancer in the gastric remnant (CGR) including 6 cases in Xian is presented. The detection rate of CGR consisting of different interval groups was 3.16%. The average age was 52.4 years, and Male: female ratio was 10:1. The average interval from the previous operation to the detection was 13.9 years. The interval of the subgroup over 30 years of age at the first operation was shorter than that of the subgroup below 30 years. The highest incidence was found in anastomotic stoma (58.1%) and cardia (32.3%). Borrmann I was the most common pathological type. Confirmed diagnostic rate with fibergastroscope was 81.8%. It is imperative that physician should follow up the patients with stomach remnant. No matter what the results of gastrointestinal barium study may be, the patients should undergo fibergastroscopic examination. The pathogenesis of CGR is also discussed.