Reduction of thyroxine-induced necrotic foci and thrombi in the mouse liver by androgen, oestrogen and glucocorticoid but not by progesterone

Injections of thyroxine (T4) at a dose of 10 micrograms/mouse/day into castrated adult female or male C57BL/6 mice for 3 weeks induced multiple necrotic foci and portal thrombi in the liver at high incidences. However, injections of T4 into intact female or male mice resulted in the marked decrease in their incidences. Furthermore, injections of 5 alpha-dihydrotestosterone at doses more than 50 micrograms/mouse/day, oestradiol-17 beta at doses of 0.2 and 1 micrograms/mouse/day or dexamethasone at doses more than 20 micrograms/mouse/day into castrated female mice markedly reduced incidences of necrotic foci and thrombi induced by T4, while injections of progesterone did not show any effects on them. The present results indicate that an excess of thyroid hormone causes the hepatic impairment in castrated mice and that androgen and oestrogen at physiological doses, and glucocorticoid at pharmacological doses prevent it.

Suppressive effect of estrogen on hepatocellular tumorigenesis induced in mice by 3'-methyl-4-dimethylaminoazobenzene

Treatment of female C57BL/6 x DS-F1 mice with 3'-methyl-4- dimethylaminoazobenzene (3'-Me-DAB) neonatally resulted in the development of hepatocellular adenomatous nodules. Ovariectomy at 1 month of age greatly hastened the time of appearance of these nodules and significantly increased their incidence. The incidence of adenomatous nodules in females ovariectomized at 1 month of age was about 70% at 12 months of age, and was decreased to 4% by implantation of a pellet containing estradiol-17 beta (E2 pellet) at 1 month of age (at the time of ovariectomy). The incidence of adenomatous nodules at 12 months of age was not decreased significantly when the implanted E2 pellet was removed at 4 or 6 months of age, but was decreased significantly when it was removed at 8 or 10 months of age. Implantation of E2 pellets into ovariectomized females at 4 and 6 months of age decreased the incidence of adenomatous nodules as effectively as their implantation at 1 month of age. The implantation of E2 pellets into ovariectomized females at 8 or 10 months of age resulted in significantly lower incidences of adenomatous nodules at 12 months of age, than that in females ovariectomized at 1 month of age. The present results suggest that the ovarian hormone, estrogen suppresses the development of hepatocellular tumors induced by 3'-Me-DAB, exerting its effect from about 6 months of age.

Enhancement by thyroxine of gastric carcinogenesis induced by N-methyl-N'-nitro-N-nitrosoguanidine in Wistar rats

The affects of L-thyroxine (T4) on the incidence and histology of gastric cancers induced by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), and on the labelling index of gastric mucosal epithelial cells were investigated in Wistar rats. After oral treatment with MNNG for 25 weeks, the rats received s.c. injections of T4 (0.2 microgram kg-1) in depot form every other day until the end of the experiment in Week 52. This long-term treatment with T4 significantly increased the incidence of gastric cancers in Week 52. However, it did not influence the histological type of the gastric cancers. It also caused significant increases in the labelling indices of the fundic and antral epithelial cells. These findings indicate that T4 enhances the development of gastric cancers, and that its effect may be related to its effect in increasing proliferation of gastric epithelial cells.

Suppression by oestrogen of hepatocellular tumourigenesis induced in mice by 3'-methyl-4-dimethylaminoazobenzene

Treatment of female C57BL/6 x DS-F1 mice with 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) neonatally resulted in the development of adenomatous nodules and glucose-6-phosphatase (G-6-Pase) deficient foci at 8 and 6 months of age, respectively. Ovariectomy of these mice at 1 month of age hastened the development and increased the incidences of these lesions. Subcutaneous implantation of estradiol-17 beta (E2) with ovariectomy at 1 month of age markedly decreased the incidences of adenomatous nodules and G-6-Pase deficient foci at 10 or 12 months of age, but subcutaneous implantation of progesterone did not reduce their incidences. Subcutaneous implantation of E2 into ovariectomised mice at 6 months of age resulted in significant decreases in the incidences of adenomatous nodules and G-6-Pase deficient foci at 10 months of age, but implantation of E2 into the spleen of ovariectomised mice of the same age had no effect on their incidences. The present results suggest that E2 suppresses the development of adenomatous nodules and G-6-Pase deficient foci induced in the mouse liver by 3'-Me-DAB by actions on tissues other than the liver.

Prognostic value of periodic Acid-schiff (pas) staining of fine-needle aspirates from patients with primary hepatocellular-carcinoma

The relationships of cytological findings on periodic acid-Schiff (PAS) staining of fine-needle aspirates of hepatocellular carcinomas (HCC) with the length of survival of patients, their therapeutic response after transcatheter arterial embolization (TAE), and the tumor volume doubling time (TVDT) before chemoembolization were investigated in 74 patients with primary HCC. On the basis of cytologic findings on PAS-staining, HCC was classified into PAS-positive, mixed, and PAS-negative types. The two-year survival (70%) of patients with PAS-positive HCC was significantly longer than those of patients with the mixed or PAS-negative type of HCC. The TVDT of PAS-positive HCC was also significantly longer than that of the mixed type of HCC. These findings indicate that cytological findings on PAS-staining of HCC are useful in assessing the prognosis of patients with HCC.

Effects of pretreatment with androgen or thyroid hormone on androgen-induced proliferation of granular convoluted tubular cells in mouse submandibular glands

The effects of pretreatment with androgen or thyroid hormone on androgen-induced proliferation of granular convoluted tubular cells (GCT cells) in the submandibular glands of ovariectomized female BALB/c or C57BL/6 mice were investigated. The proliferation of GCT cells was estimated by their labeling index. Daily injections of 5 alpha-dihydrotestosterone (DHT) (100 micrograms/mouse/day) caused a transient increase in the labeling index of GCT cells of ovariectomized 60-day-old BALB/c mice during the first four injections, but injections of thyroxine (T4) (15 micrograms/mouse/day) did not. On the other hand, both DHT and T4 increased the esteroprotease activity, a marker of the differentiation of GCT cells, time dependently. Injections of DHT into ovariectomized 102-day-old BALB/c mice also caused a transient increase in the labeling index of GCT cells. However, pretreatment of ovariectomized 60-day-old BALB/c mice with DHT for 4 or 14 days completely abolished the DHT-induced increase in the labeling index of 102-day-old mice, and pretreatment with T4 for 14 days reduced this increase. Pretreatment with DHT or T4 for 14 days did not affect the DHT-induced increase in esteroprotease activity. Pretreatment of ovariectomized 60-day-old C57BL/6 mice with DHT for 14 days also completely abolished the DHT-induced increase in the labeling index of GCT cells at the age of 102 days, but pretreatment with T4 for 14 days did not affect the increase.(ABSTRACT TRUNCATED AT 250 WORDS)

Binding of c-Myb to the core sequence of the CD4 promoter

We identified a regulatory region of the mouse CD4 promoter by both in vivo and in vitro analysis. The results of transient transfection assays indicated that the dominant transcription activating element within the CD4 promoter is located at -82 to -42. Elimination of this element, by linear deletion or specific mutation, significantly reduced transcriptional activity from this promoter. DNase I footprinting and gel mobility shift assays confirmed that the region -90 to -64 acts as the binding site of a specific nuclear factor, designated NF-CD4. In this region, an 11 bp core motif (CAACAACTGGG; -82 to -72) was found to be sufficient for the binding and transcriptional activation of the NF-CD4. This motif contains a consensus sequence for binding of c-Myb and proteins with helix-loop-helix structures. Indeed, bacterially-synthesized c-Myb specifically binds to this motif for NF-CD4. Furthermore, binding of NF-CD4 to the promoter region was specifically inhibited by the addition of anti-Myb antibodies. The evidence strongly suggests that c-Myb binds, in a sequence-specific fashion, to the core region of the CD4 promoter defined by functional assays and that this proto-oncogene product appears to play a role in the complex regulation of CD4 gene expression during T cell development.

Detection of Mycoplasma meleagridis by polymerase chain reaction

A pair of 32 base primers was synthesized based on the DNA sequence data of a Mycoplasma meleagridis (MM) species-specific recombinant, pMM-2. The primers were used in a MM-polymerase chain reaction (PCR) to amplify a target DNA of approximately 850 bp. Annealing temperatures ranging from 58 degrees C to 61 degrees C could be used for the MM-PCR without loss of specificity. The primers amplified 1 ng of DNA from 17 strains of MM, but not 10 ng of DNA from 16 heterologous species of avian mycoplasma, pUC8 plasmid, lambda phage or calf thymus DNA. The minimum amount of target DNA detected by MM-PCR was 10 fg, which indicated that this procedure was 100000 times more sensitive than dot blot methodology using an MM recombinant DNA probe.

The localization of nitric oxide synthase in the rat eye and related cranial ganglia

Nitric oxide synthase is the biosynthetic enzyme for the free radical neurotransmitter nitric oxide. Using an affinity-purified antiserum, nitric oxide synthase was found to be localized to peripheral ocular nerve fibers, related cranial ganglia, and the retina of the rat. In the eye, nitric oxide synthase-like immunoreactive peripheral nerve fibers were visualized mainly in the choroid and about limbal blood vessels. The anterior uvea was quite sparsely innervated, and the cornea was negative. Many principal neurons in the pterygopalatine ganglion were immunoreactive for nitric oxide synthase while very few cells stained in the superior cervical and trigeminal ganglia. Virtually all nitric oxide synthase-like immunoreactive pterygopalatine cells were also immunostained for vasoactive intestinal polypeptide; nitric oxide synthase also partially co-localized with neuropeptide Y in some of the neurons of this ganglion. Pterygopalatine ganglionectomy significantly reduced the number of peripheral nitric oxide synthase-like immunoreactive nerve fibers in the eye. A variety of immunoreactive retinal cells were seen. Most cells in the inner nuclear layer or ganglion cell layer corresponded morphologically to amacrine cells and displaced amacrine cells. Interplexiform cells and occasional faintly stained cells in the outer portion of the inner nuclear layer also were visualized. Nicotinamide adenine dinucleotide phosphate diaphorase histochemistry generally stained cells of similar distribution but did reveal somewhat more extensive localizations in peripheral ocular tissues, the ciliary ganglion, and the retina, compared with nitric oxide synthase immunohistochemistry. Nitric oxide synthase thus localizes to peripheral ocular nerve fibers, chiefly parasympathetic in nature and derived from the pterygopalatine ganglion, and to several cell types in the retina. Nitric oxide probably acts as a choroidal vasodilator of parasympathetic origin in the eye; the neuropeptide co-localizations in the pterygopalatine ganglion suggest complex neuromodulatory interactions. The retinal localizations imply potential neurotransmitter functions for nitric oxide in this tissue.

Species-specific recombinant DNA probes for Mycoplasma meleagridis

Two recombinant DNA probes (pMM-2 and pMM-13) were isolated from a Mycoplasma meleagridis strain 17529 genomic library prepared in plasmid pUC8, and Escherichia coli strain JM83. In dot blot assays, 32P-labeled pMM-13 with a DNA insert of 3.5 kbp, hybridized with 18 isolates of M. meleagridis but not with 16 other known species of avian mycoplasmas. Except for weaker signals on hybridization with the M. meleagridis cultures, pMM-2 with an DNA insert of 0.85 kbp, showed a similar reaction pattern. The minimal concentration of M. meleagridis strain 17529 chromosomal DNA that pMM-13 and pMM-2 detected were 1 and 8 ng, respectively. Neither probe hybridized with chromosomal DNA of M. gallisepticum strain S6, M. synoviae strain WVU-1853, or M. iowae strain I-695 at concentration of 256 ng.

Hypoxia induces a human macrophage cell line to release tumor necrosis factor-alpha and its soluble receptors in vitro

Tissue hypoxia following hemorrhage and trauma is a possible initiating factor of the generalized inflammatory response seen after shock. The role of hypoxia in the release from a human monocyte cell line (THP-1) of tumor necrosis factor-alpha (TNF alpha) and its soluble membrane receptors (TNF alpha R) in-vitro is investigated in this study. Flat-bottom plates with 500,000 THP-1 cells/ml were placed in air-tight sealed boxes and exposed to hypoxia (O2 = 1%) or controls (O2 = 9%) for up to 24 hr. Supernatants were tested for TNF alpha, as well as 55- and 75-kDa soluble receptors for TNF alpha, by ELISA. Cell viability was assessed by vital dye uptake and was found to be maintained throughout hypoxic exposure. Medium pH levels were within normal range. In eight experiments conducted in duplicate, minimal change over 24 hr occurred in control samples. Control mean and SD were: TNF alpha = 12.0 +/- 4.2, 55-kDa R = 34.6 +/- 2.03, and 75-kDa R = 38.88 +/- 9.68 pg/ml. During hypoxia, TNF alpha was released as early as the first 30 min of exposure (41.3 +/- 2.3 pg/ml) with a small peak at 1 hr (52 +/- 5.0 pg/ml) and a later more pronounced peak at 18 hr (526 +/- 48 pg/ml). Both 55- and 75-kDa R were released by the hypoxic monocytes; release was progressive and was maximal at 24 hr in this study. Maximal release value of 55-kDa R was 236 +/- 15 pg/ml, while for 75-kDa R it was 2450 +/- 63 pg/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

N omega-nitro-L-arginine, an inhibitor of nitric oxide synthesis, decreases noradrenaline outflow in rat isolated perfused mesenteric vasculature

In the isolated perfused rat mesenteric vasculature with intestine attached N omega-nitro-L-arginine (L-NNA) (30 mumol/l), an inhibitor of nitric oxide (NO) synthesis from L-arginine, did not alter spontaneous noradrenaline outflow. Transmural field stimulation (2-10 Hz) caused a frequency-dependent increase in noradrenaline outflow. The evoked overflow was reduced by L-NNA. L-Arginine (0.3 mmol/l) attenuated the inhibition of noradrenaline overflow by L-NNA. These results suggest that NO increases the release of noradrenaline in rat mesenteric vasculature.

Expression of CD45 isoforms in fresh and IL-2-cultured tumor-infiltrating lymphocytes from basal cell carcinoma

Immunohistochemistry and flow cytometry analyses were performed to characterize the specific T cell subpopulations infiltrating basal cell carcinomas (BCC) and to determine their phenotypic response to in vitro expansion with IL-2. Tumor-infiltrating lymphocytes (TIL) within BCC predominantly expressed the CD45RO (activated or "memory") phenotype (65 +/- 3%) and the percentage of TIL expressing CD45RO consistently increased when cultured in vitro with IL-2 (85 +/- 5%). In comparison, fresh normal peripheral blood lymphocytes predominantly expressed the CD45RA (naive) phenotype (79 +/- 4%), but shifted to the expression of CD45RO following in vitro expansion in IL-2 (86 +/- 6%). To determine whether IL-2 alone, in the absence of antigen or mitogen, can promote naive lymphocytes to convert from the expression of the CD45RA isoform to the CD45RO isoform, we cultured purified CD45RA+ lymphocytes in IL-2. After three weeks in culture, 90% of the lymphocytes expressed exclusively CD45RO. We conclude that tumor-infiltrating lymphocytes from BCC predominantly express CD45RO and that this expression may represent specific antigen stimulation and/or in situ activation by cytokines.

Promoting effect of ovariectomy on hepatocellular tumorigenesis induced in mice by 3'-methyl-4-dimethylaminoazobenzene

The treatment of female C57BL/6 x DS-F1 mice with 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) at 10, 12, 14, 16 and 18 days of age resulted in the development of hepatocellular adenomatous nodules after 10 months of age. Ovariectomy in these mice at 1 month of age hastened the development of adenomatous nodules, which then first appeared at 8 months of age. The incidence of adenomatous nodules in females ovariectomized at the age of 1 month was much higher than that in intact females of the same age. These results showed that the ovaries exerted a suppressive effect on the development of adenomatous nodules. To determine the time from which the ovaries exert this suppressive effect, females were ovariectomized at 4, 6, 8, and 10 months of age, and the incidences of adenomatous nodules were compared at 10 and 12 months of age. Delayed ovariectomy after 8 months of age did decrease the incidence of adenomatous nodules at 10 and 12 months of age, but ovariectomy after 4 and 6 months of age did not. When the incidence of adenomatous nodules in females ovariectomized at 10 months of age was examined over the subsequent 6 months, it became significantly higher after 14 months of age compared with that in intact females. The results show that the ovariectomy has the promoting effect on the development of adenomatous nodules in the liver induced by 3'-Me-DAB after 6 months of age.

Effects of Structural Disorder on the Electronic Properties of Silicon: Tight-Binding Calculations of Grain Boundaries

The atomic and electronic structures of tilt and twist boundaries in Si have been calculated by using the transferable semi-empirical tight-binding (SETB) method, and the relations between the local structural disorder and the electronic properties of Si have been obtained clearly. The odd-membered rings and the four-membered rings induce the changes of the shape of the local density of states (LDOS). The bond distortions generate the peaks at the band edges in the LDOS, and greatly distorted bonds induce the weak-bond states inside the band gap. The three-coordinated defect generates a deep state in the band gap, which is much localized at the three-coordinated atom. The five-coordinated defect generates both deep and shallow states. The deep state is localized in the neighboring atoms except the five-coordinated atom, although the shallow states exist among the five-coordinated atom and the neighboring atoms. Configurations of boundaries are very effective in order to clarify the effects of the local structural disorder in amorphous SI.

Mycoplasma gallisepticum F-vaccine strain-specific polymerase chain reaction

A Mycoplasma gallisepticum (MG) F-vaccine strain polymerase chain reaction (PCR) (MGF-PCR) was developed and standardized. The origin of the primers was a clone (p08-M6#17) that contained an MG F-strain-specific DNA fragment of 6.0 kilobase pairs designated fMGF-1. Both ends of fMGF-1 (BamHI and EcoRI) were sequenced, and regions adequate for the primers were chosen. Seven 25-base primers were synthesized, and two near the EcoRI end (MGF-P1 left [L] and right [R]) were selected for MGF-PCR, MGF-P1 L and R amplified a DNA product of 524 base pairs (bp) that was directed at F-strain-related MG only. None of 16 other species of avian mycoplasmas that were tested yielded MGF-PCR product. MGF-PCR was able to consistently detect F-strain samples containing 54 cells or more and inconsistently (at least one positive out of five replicates) in samples with fewer organisms. The MGF-PCR products were visualized either by gel electrophoresis or Southern blot hybridization with a probe containing an identical base sequence as the 524-bp product amplified by MGF-PCR. The MGF-PCR was 1000 to 10,000 times more sensitive than dot-blot assays using two MG F-strain-specific probes.

Amplification of Mycoplasma iowae using polymerase chain reaction

Based on sequence data of Mycoplasma iowae recombinant DNA probe, pMI-12, two 25-base primers were synthesized for use in the polymerase chain reaction (PCR). An M. iowae species-specific 299-base pair product was amplified by the primers. An annealing temperature of 58.5 C was critical for detecting all members of this heterogeneous species while maintaining specificity of the M. iowae PCR. The minimum amount of target DNA detected by M. iowae PCR was 1 pg, which was 1000 times more sensitive than the dot-blot assay using M. iowae recombinant DNA probes.

Cytologic examination of pure pancreatic juice in the diagnosis of pancreatic carcinoma. The endoscopic retrograde intraductal catheter aspiration cytologic technique

BACKGROUND

Although cytologic examination of pure pancreatic juice obtained with a duodenofiberscope has been useful for the diagnosis of pancreatic carcinoma, the rate of false-negative results is reported to be high. To eliminate these false-negative results, the authors developed a new technique, endoscopic retrograde intraductal catheter aspiration cytology, especially for an accurate cytologic diagnosis of carcinoma of the body or tail of the pancreas.

METHODS

The accuracy of conventional cytologic examination of pure pancreatic juice was assessed in 25 patients with pancreatic carcinoma, 29 patients with pancreatitis, and 52 control subjects. Pure pancreatic juice was collected from the pancreatic duct by endoscopic cannulation using a videoimaging duodenoscope after intravenous administration of secretin. The new endoscopic retrograde intraductal catheter aspiration technique was used in four patients with carcinoma of the body or tail of the pancreas and five patients with localized pancreatitis in whom a correct diagnosis was not made by previous cytologic examination of pure pancreatic juice.

RESULTS

Positive cytologic findings were obtained in 76% of the patients with pancreatic carcinoma. Positive cytologic results were more frequent in patients with carcinoma of the head of the pancreas than in those with carcinoma of the body or tail. By the new technique, positive cytologic results were obtained in all of the patients with pancreatic carcinoma. This technique caused no severe complications.

CONCLUSIONS

This procedure of endoscopic retrograde intraductal catheter aspiration cytology seems useful for diagnosis of pancreatic carcinoma.

Cytologic examination of pure pancreatic juice in the diagnosis of pancreatic carcinoma. The endoscopic retrograde intraductal catheter aspiration cytologic technique

BACKGROUND

Although cytologic examination of pure pancreatic juice obtained with a duodenofiberscope has been useful for the diagnosis of pancreatic carcinoma, the rate of false-negative results is reported to be high. To eliminate these false-negative results, the authors developed a new technique, endoscopic retrograde intraductal catheter aspiration cytology, especially for an accurate cytologic diagnosis of carcinoma of the body or tail of the pancreas.

METHODS

The accuracy of conventional cytologic examination of pure pancreatic juice was assessed in 25 patients with pancreatic carcinoma, 29 patients with pancreatitis, and 52 control subjects. Pure pancreatic juice was collected from the pancreatic duct by endoscopic cannulation using a videoimaging duodenoscope after intravenous administration of secretin. The new endoscopic retrograde intraductal catheter aspiration technique was used in four patients with carcinoma of the body or tail of the pancreas and five patients with localized pancreatitis in whom a correct diagnosis was not made by previous cytologic examination of pure pancreatic juice.

RESULTS

Positive cytologic findings were obtained in 76% of the patients with pancreatic carcinoma. Positive cytologic results were more frequent in patients with carcinoma of the head of the pancreas than in those with carcinoma of the body or tail. By the new technique, positive cytologic results were obtained in all of the patients with pancreatic carcinoma. This technique caused no severe complications.

CONCLUSIONS

This procedure of endoscopic retrograde intraductal catheter aspiration cytology seems useful for diagnosis of pancreatic carcinoma.

Regional differences of the contractile responses to acetylcholine and neurokinin A in rabbit airway: heterogeneous distribution of the metabolic enzymes

1. Experiments were designed to determine whether differences exist in the sensitivity to muscarinic and tachykinin agonists in rabbit airways. 2. The rank order of sensitivity (pD2 value) to acetylcholine was: trachea > proximal bronchus > distal bronchus, whereas no regional difference was observed in the sensitivity to carbamylcholine which is resistant to acetylcholinesterase. 3. Acetylcholinesterase activity was greater in the distal than in the proximal airway. 4. In the absence of the peptidase inhibitor, phosphoramidon, the pD2 values of neurokinin A (NKA) and substance P (SP) in trachea were significantly greater than that in bronchus, whereas no regional difference was observed in the NK1 selective agonist, substance P methyl ester (SPOMe). 5. Application of phosphoramidon (10 microM) to avoid peptide degradation abolished the regional difference of the pD2 values of SP. 6. In conclusion, regional differences in sensitivities to acetylcholine and NKA in the rabbit airway were suggested to be due to distribution to the metabolic enzymes of these drugs.

Enhancement by androgen of the angiogenic ability of androgen-responsive Shionogi carcinoma 115

The effects of various steroids on the induction of angiogenesis by androgen-responsive Shionogi carcinoma 115 (SC115) were investigated by implanting a piece of a SC115 tumor tissue into a rabbit cornea together with a pellet containing each steroid (250 micrograms) and by examining neovascularization from the limbus. SC115 tumor tissues induced neovascularization in 42% corneas in the absence of steroids, and in 31, 63, 80 and 4% in the presence of estradiol-17 beta, progesterone, testosterone and dexamethasone, respectively. Only testosterone significantly increased the percentage of corneas with neovascularization, while dexamethasone significantly decreased it. Testosterone itself induced no neovascularization, and dexamethasone also inhibited neovascularization induced by acidic fibroblast growth factor. The present results suggest that androgen increases the secretion of an angiogenic factor(s) by an androgen-responsive SC115 tumor, while dexamethasone inhibits angiogenesis induced by the angiogenic factor(s).

[Localization of human sterol carrier protein 2 gene and cDNA expression in COS-7 cell]

Sterol carrier protein 2 (SCP2) is known to be an important polypeptide in intracellular sterol and lipid movement. Here are reported the cloning and expression of a cDNA encoding human SCP2, and the assignment of SCP2 gene to human chromosome 1. The 1,229 bp cDNA contains an open reading frame and the encoded polypeptide consists of 143 amino acids. This polypeptide is very similar in amino acid composition to human, bovine and rat liver SCP2. The deduced amino acid sequence of this cDNA has a 20-residue amino-terminal leader sequence with mature SCP2. Northern blot analysis suggests that there are 1.8 kb and 3.2 kb mRNA species in human liver poly (A)+RNA. PCR analysis of human x rodent somatic cell hybrid panels indicates that the gene encoding SCP2 is on human chromosome 1. Transient expression of the human liver SCP2 cDNA in COS-7 cells shows a 15.3KDa polypeptide and increased amounts of a 13.2KDa polypeptide. Coexpression of the SCP2 cDNA with cholesterol side-chain cleavage enzyme and adrenodoxin cDNAs resulted in a 2.5-fold progestin synthesis in comparison with that of the steroidogenic enzyme system alone. These findings suggest that SCP2 plays a role in regulating steroidogenesis, among other possible functions.

[Limits of duration of chest tube drainage in the first episode of spontaneous pneumothorax]

We treated three patients with spontaneous left pneumothorax who underwent a long period of chest tube drainage before surgery. Case 1 was a 61-year-old man. On day 13 after drainage started, much air leakage occurred and surgery was done the next day. Case 2 was a 57-year-old man. Drainage failed to allow the air leakage to seal. The patient did not consent to surgery for about a month, but on day 38 after drainage started, he underwent surgery. Case 3 was a 19-year-old man. First, chest tube drainage was successful and he was extubated on day 16. However, pneumothorax recurred the next day. Liver dysfunction delayed surgical treatment, and the patient underwent surgery on day 54 after the first drainage. Postoperatively, he developed wound infection of the chest tube route and aseptic pleurisy of unknown origin. Limits of duration of unsuccessful chest tube drainage for the first episode of spontaneous pneumothorax are controversial. These cases suggest that when two weeks of chest tube drainage is unsuccessful, surgery should be undertaken in view of postoperative complication and social indications.