[Experimental study on the effect of nourishing yin and tranquilizing of yangyin anshen koufuye]

Yangyin Anshen Koufuye could obviously decrease the spontaneous activity of rats, effectively shorten the process of falling into sleep of normal rats which were injected pentobarbital sodium and prolong the sleeping time. The effect of sedation and hypnotism were the same as Zhaoren Anshen Koufuye. Yangyin Anshen Koufuye also could markedly reduce the serum tensity of T3, T4 of hyperthyroid rats, which equaled to TCM's deficiency of yin. It also could prevent the glycogen content of liver from decreasing, decrease heart rate, resist weight losing, thus to show the effect of nourishing Yin and tranquilizing.

[Common mutation analysis for patients found in Tianjin area with glucose-6-phosphate dehydrogenase deficiency]

OBJECTIVE

To study the types of glucose-6-phosphate dehydrogenase (G6PD) gene mutation in North China and to find the relationship between the mutations and population emigrants.

METHODS

DNA samples from 22 unrelated patients(21 male and 1 female) with G6PD deficiency from Tianjin area in North China were studied for the three common mutations by using both mismatched primers mediated polymerase chain reaction/ restriction enzyme analysis and dideoxy fingerprinting methods.

RESULTS

Eight patients(8/22, 36.4%) were found to have the mutation R459L(1376G-->T), and seven patients (7/22, 31.8%) were found to have the mutation R463H (1388G-->A). In three of (3/7) other seven patients (7/22), H32R(95A-->G) were detected; one patient (1/3) was identified to have H32R (95A-->G) mutation.

CONCLUSION

The three common mutations in South China are also found in North China. However, most of the patients in Tianjin are also the later generations of Southern emigrants.

[Expression detection and location analysis of BstNI isoschizomer restriction-modification system gene]

Some genetic markers of E. coli HB101 and JM110 were identified, two bacterial strains were used as recipients respectively to detect the expression of a restriction endonuclease(R) gene and a methylase(M) gene of BstNI isoschizomer restriction-modification system. DNA fragment containing the R-M genes was deleted unilaterally with exoIII and 23 deletion subclones were obtained. According to the Enzyme activity of each subclone, R and M gene were located respectively at the regions of 0.2-->1.4 kb and 1.5-->3.3 kb from cloning site PstI. Analysis showed that the R. M system belongs to type II, two genes are controlled by the different promoters; the recognition sequence of this system is the same as that of DNA-cytosine methyltransferase(Dcm), the latter's methylation function can resist the R enzyme. It was interesting that the recombinant plasmid with an R+ M- genotype appeared to be lethal to dcm+ hosts yet. This indicated that the M gene closely linking to R gene is of critical importance for the existence of the R-M system in process of evolution.

[Determination of high temperature compressive strength and refractory degree of die material compatible with slip casting core of sintered titanium powder]

OBJECTIVE

The refractory die is the precondition for developing slip casting core of sintered powder. This study is to determine the high temperature properties of the refractory die material compatible with slip casting core.

METHODS

To prepare three cylindrical specimens (phi 10 x 15 mm) and determine their compressive strength at 1000 degrees C: to make four specimens in flat-topped cone for determining the practical refractory degree by decreasing the pressing temperatures in a sequence of 1420, 1400, 1350 and 1100 degrees C.

RESULTS

The compressive strength of this material was 17.8 MPa at 1000 degrees C. Its practical refractory degree was higher than 1100 degrees C.

CONCLUSION

The high temperature properties of the refractory die material that we developed meet the demand of slip casting core of sintered powder.

[Study on the contamination of algae and microcystins in water sources of Zhengzhou City]

Planktonic algae and microcystins (MCYST) were detected constantly in water sources of Zhengzhou City from 1996 to 1997. There is significant seasonal variation of the density of algae. The peak of algae occurring in February and December is about 1,068,000/L. The contents of MCYST in July, 1995 and in January, 1996 were over 200 ng/L. According to the Carlson's trophic state index(TSI), and indexes of total nitrogen, phosphorus, COD value and algae density, an eutrophication of water source having emerged in Zhengzhou is considered.

Metabolic interactions between mibefradil and HMG-CoA reductase inhibitors: an in vitro investigation with human liver preparations

AIMS

To determine the effects of mibefradil on the nletabolism in human liver microsomal preparations of the HMG-CoA reductase inhibitors simvastatin, lovastatin, atorvastatin, cerivastatin and fluvastatin.

METHODS

Metabolism of the above five statins (0.5, 5 or 10 microM), as well as of specific CYP3A4/5 and CYP2C8/9 marker substrates, was examined in human liver microsomal preparations in the presence and absence of mibefradil (0.1-50 microM).

RESULTS

Mibefradil inhibited, in a concentration-dependent fashion, the metabolism of the four statins (simvastatin, lovastatin, atorvastatin and cerivastatin) known to be substrates for CYP3A. The potency of inhibition was such that the IC50 values (<1 microM) for inhibition of all of the CYP3A substrates fell within the therapeutic plasma concentrations of mibefradil, and was comparable with that of ketoconazole. However, the inhibition by mibefradil, unlike that of ketoconazole, was at least in part mechanism-based. Based on the kinetics of its inhibition of hepatic testosterone 6beta-hydroxylase activity, mibefradil was judged to be a powerful mechanism-based inhibitor of CYP3A4/5, with values for Kinactivation, Ki and partition ratio (moles of mibefradil metabolized per moles of enzyme inactivated) of 0.4 min(-1), 2.3 microM and 1.7, respectively. In contrast to the results with substrates of CYP3A, metabolism of fluvastatin, a substrate of CYP2C8/9, and the hydroxylation of tolbutamide, a functional probe for CYP2C8/9, were not inhibited by mibefradil.

CONCLUSION

Mibefradil, at therapeutically relevant concentrations, strongly suppressed the metabolism in human liver microsomes of simvastatin, lovastatin, atorvastatin and cerivastatin through its inhibitory effects on CYP3A4/5, while the effects of mibefradil on fluvastatin, a substrate for CYP2C8/9, were minimal in this system. Since mibefradil is a potent mechanism-based inhibitor of CYP3A4/5, it is anticipated that clinically significant drug-drug interactions will likely ensue when mibefradil is coadministered with agents which are cleared primarily by CYP3A-mediated pathways.

Difference in the burst patterns of digastric and mylohyoid activities during feeding in the freely behaving rabbit

Burst patterns in the digastric, mylohyoid, and masseter muscles and the resultant jaw movement orbits during chewing and swallowing were investigated in the freely behaving rabbit. Activities in the posterior mylohyoid fibers consisted of two continuous bursts. Peaks in the first burst of the posterior fibers occurred in the middle part of opening and preceded the digastric burst. Peaks in the second burst occurred in the final part of opening and coincided with those in the working side of the digastric burst. After removal of the bilateral digastric muscles, the gape size during chewing was largely reduced in the final part of opening and in the early part of closing. The results suggest that (a) the digastric may have a role in opening the mandible widely beyond the rest position but may not have a major role in the control of the horizontal (mediolateral) jaw movement, (b) the posterior mylohyoid fibers may have a function as an elevator of the tongue in the early part of opening, and (c) the posterior mylohyoid fibers may have a function as a depressor of the jaw in the late part of opening. Electromyographic burst in the mylohyoid muscle began with marked activity in the mid-closing phase. The results support a role for the mylohyoid muscle as a leading muscle of swallowing. Swallowing events in the rabbit are easily distinguished from the activities of the mylohyoid muscle and the thyrohyoid muscle.

Immunoregulatory role of CD8alpha in the veto effect

BACKGROUND

Allogeneic bone marrow cell (allo-BMC) infusion induces tolerance to incompatible renal allografts in rhesus macaques after depletion of peripheral T lymphocytes with cytolytic anti-T cell antibodies. The tolerogenic effect of allo-BMC, ascribed to a veto mechanism, associates with specific functional deletion of antidonor cytotoxic T lymphocyte precursor (CTLp), and is dependent on a CD8+ donor BMC subset. In previous studies, the CD8 molecule was implicated by loss of suppression after blocking interaction between CD8 on allo-BMC and major histocompatibility complex class Ialpha3 domain on CTLp. CD8 cross-linking on BMC induced secretion of active transforming growth factor-beta1 (TGF-beta1), suggesting a regulatory mechanism(s) operating via a CD8-mediated signaling pathway.

METHODS

CD8 on rhesus cells was cross-linked using IgG-conjugated beads, and TGF-beta1 mRNA and protein were quantified. CD8+ cells were tested for veto activity by mixed lymphocyte reaction (MLR)-induced cell-mediated lymphocytotoxicity (CML) assay. Activated rhesus T cells exposed to TGF-beta1 were examined for apoptosis by TdT-mediated end-labeling and annexin staining.

RESULTS

CD8 cross-linking induces accumulation of TGF-beta1 mRNA and protein. Both CD3- CD8+CD16+ and CD3+ CD8+CD16- subsets of allo-BMC up-regulate TGF-beta1 mRNA after CD8 cross-linking, and exhibit veto activity. The CD3-CD8+CD16+ subset expresses more TGF-beta1 mRNA and increased veto activity at low BMC/CTLp ratios. Exposure of activated T cells to TGF-beta1 induces apoptosis.

CONCLUSIONS

CD8+ allo-BMC are enriched for veto activity and activation via CD8 induces TGF-beta1 mRNA and protein accumulation. These results agree with the hypothesis that paracrine TGF-beta1 may be involved in peripheral deletion of alloreactive CTLp by CD8+ allo-BMC. We suggest that TGF-beta1 overexpression by donor lymphohematopoietic cells may enhance tolerance induction.

[A clinico-pathological study of neuroendocrine tumors in stomach]

OBJECTIVE

To study the pathological classification of gastric neuroendocrine tumors and its clinico-pathological significance.

METHODS

Paraffin sections of totally 52 gastric neuroendocrine tumors including 42 carcinoid tumors were studied with immunohistochemical technique, which involved 9 endocrine markers of hormones antibodies and electronic microscopy for investigating the endocrine cells and the contiguous gastric mucosa of the neuroendocrine tumors.

RESULTS

The 52 gastric neuroendocrine tumors were divided into three types: Type I, carcinoid, associated with atrophic gastritis, altogether 26 cases. Tumor extension was limited in the mucosa or submucosa, accompanying with hypergastrinemia and G cell hyperplasia. This type is consistently preceded by and associated with generalized proliferation of endocrine cells in the mucosa at fundus. Type II, carcinoid of sporadic type, totally 16 cases, not associating with hypergastrinemia, was more aggressive. Type III, Neuroendocrine carcinomas (10 cases), were highly aggressive tumors.

CONCLUSION

A correct identification of different types of gastric endocrine tumors is important and implicit for the treatment and prognosis of neuroendocrine tumors.

Pharmacological effects of methamphetamine and other stimulants via inhalation exposure

The effects of methamphetamine-HCl, methcathinone-HCl, cocaine and ephedrine on locomotor stimulation were compared between inhalation exposure and i.v. injection in mice. Methamphetamine-HCl was readily volatilized upon heating at 300 degrees C in a glass pipe with only trace amounts of amphetamine being produced. The ED50 dose (9.4 and 6.5 mumol/kg for inhalation exposure and i.v. injections, respectively) and biodisposition of methamphetamine-HCl were similar for both routes of administration. Methcathinone-HCl and cocaine were readily volatilized. Their dose response profiles also appeared similar for both routes of administration. Ephedrine did not appear to be easily volatilized and was only effective in stimulating locomotor activity after i.v. administration. These findings indicate that inhalation exposure to methamphetamine-HCl, cocaine and methcathinone possess similar pharmacological characteristics as the i.v. route of administration. In particular, this model may have implications in predicting the pharmacological activity of various stimulants via the inhalation route of administration.

Inhibition of glycogen synthase kinase 3beta activity regulates proliferation of cultured cerebellar granule cells

Insulin-like growth factor I (IGF-I) is mitogenic for several types of neuronal progenitors including cerebellar granule neuron progenitors. The present study confirms that IGF-I can function as a mitogen in purified cultures of cerebellar granule cells and identifies intracellular signal transduction molecules that mediate this mitogenesis. In cultured granule cells, IGF-I inhibits GSK-3 activity and leads to phosphorylation of serine9 an inhibitory site on GSK-3beta. Phosphoinositide 3-kinase (PI3-K) activation by IGF-I can lead to phosphorylation and inactivation of GSK-3. A PI3-K inhibitor, LY294002, completely inhibited IGF-I-induced proliferation with half-maximal inhibition occurring at a concentration (1.5 micrograms) close to its reported IC50 value for inhibition of PI3-K. Lithium chloride (LiCl), a direct inhibitor of GSK-3beta, can alone stimulate granule cell proliferation and enhance proliferation induced by IGF-I. LiCl can reverse the inhibitory effect of LY294002 on granule cell proliferation suggesting that GSK-3 inhibition may be downstream of PI3-K activation in IGF-I's mitogenic pathway. Experiments further show that the expression of a dominant active form of GSK-3beta antagonizes IGF-I-induced mitogenesis. These studies support a role for inhibition of GSK-3beta activity in the signal transduction pathway by which IGF-I regulates granule neuron progenitor proliferation.

Prolyl endopeptidase from Sphingomonas capsulata: isolation and characterization of the enzyme and nucleotide sequence of the gene

Prolyl endopeptidase (prolyl oligopeptidase, EC 3.4.21.26) was purified from Sphingomonas capsulata IFO 12533, and its gene was cloned and expressed in Escherichia coli. The recombinant enzyme was markedly inhibited by diisopropyl phosphofluoridate and hardly affected by SH reagents or metal chelators, similar to the native enzyme purified from S. capsulata. Nucleotide sequencing analysis revealed an open reading frame of 2169 bp, coding for a protein of 723 amino acids with a predicted molecular weight of 78,433. The amino acid sequence was 39.6, 45.3, 38.9, and 38.3% homologous to Flavobacterium meningosepticum, Aeromonas hydrophila, porcine brain, and human T cell prolyl endopeptidase, respectively. A region near the C-terminus and the region containing the putative catalytic triad residues were highly conserved. The enzyme was crystallized by the hanging drop vapor diffusion method, using ammonium sulfate as a precipitant.

[Successful media exchange and network communication of CT digital image]

The digital image standard in medical is discussed. Based on the DICOM standard by using the media exchange and establishing the network communication between PC and CT system, we successfully acquired the CT original digital image and convert it to DICOM standard image. The CT image can easitly be read and adjusted on the PC platform.

The effect of sequential injuries on splanchnic perfusion and eicosanoid release

BACKGROUND

This study examines the hypothesis that sequential burn injury followed by intraabdominal sepsis induces significantly greater splanchnic hypoperfusion and reduced intestinal PGI2 release than either injury independently.

MATERIALS AND METHODS

Anesthetized Sprague-Dawley rats were randomized to one of four groups: BURN (45% body surface area scald burn) + cecal ligation and puncture (CLP); BURN alone; CLP alone; or uninjured controls (SHAM). Twenty-four hours following injury, superior mesenteric artery (SMA) blood flow was measured with a doppler flow probe. Splanchnic eicosanoid release (6-keto-PGF1alpha, metabolite of PGE2; TxB2, metabolite of TxA2; and PGE2) was measured in mesenteric venous effluent utilizing an isolated, perfused bowel preparation.

RESULTS

SMA blood flow was no different than that of controls 72 h following BURN injury alone; whereas CLP alone resulted in a 80% reduction in splanchnic blood flow when compared with controls (P < 0.001). SMA blood flow in animals sustaining BURN + CLP was only modestly reduced from controls (P = 0.04) and 3.6 times greater than that of animals sustaining CLP alone (P < 0.001). PGI2 was the dominant eicosanoid released by the intestine with levels 10 times greater than TxB2 and nearly 50 times greater than PGE2. CLP either alone or when combined with BURN was associated with a 60% decrease in splanchnic PGI2 release when compared to controls (P < 0.05).

CONCLUSIONS

These data suggest that moderate BURN injury in rats attenuates the severe reduction in splanchnic perfusion associated with intraabdominal sepsis and that this occurs despite profound reductions in the release of the endogenous splanchnic vasodilator PGI2.

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.