[Transcatheter arterial infusion of adriamycin-lipiodol suspension to patients with metastatic liver tumor]. Adriamycin-Lipiodol suspension was administered to 44 patients with metastatic liver tumor using the transcatheter arterial infusion method. The result revealed 23% in the over all effect (partial response or more) of the therapy which was evaluated by comparing the CT images of the tumor, 47% in the 25% or more of the decrease of the tumor, and 65%, very effective in the decrease of the smaller tumor (less than 50 cm2). Except for a case of hepatic subcapsular hematoma after the infusion of Adriamycin-Lipiodol suspension, minor complications were experienced such as abdominal pain, slight fever, and so on. No serious exacerbation in liver function test and white blood cell count was noted.


[Effect of lipiodol-cisplatinum arterial infusion chemotherapy on cellular immunity]. A Lipiodol-cisplatinum suspension (LPD/CDDP) was applied by intrahepatic arterial infusion chemotherapy to treat 15 cases of inoperable hepatoma. Pre- and post-application changes in leucocytes, monocytes, platelets and lymphocytes in patients were examined. Natural killer activity was determined and analysis by two-color method was performed. After infusion chemotherapy, leucocytosis and monocytosis were quite conspicuous. NK activity was reduced after application of LPD/CDDP, but this effect may have been partly due to the influence of methylprednisolone. Cellular immunity was not influenced by LPD/CDDP infusion without low reduction of NK activity.


[A case with hepatocellular carcinoma effectively treated by continuous hepatic arterial infusion of etoposide, epirubicin and CDDP]. A 53-year-old man who suffered from advanced hepatocellular carcinoma (HCC) was treated with hepatic arterial infusion (HAI) of Etoposide, Epirubicin and CDDP. Treatment consisted of a continuous HAI of Epirubicin (50 mg/body, day 1.7), CDDP (75 mg/body, day 2.8) and Etoposide (80 mg/body, day 4-6). He had two series of infusions and was treated by transarterial embolization using CDDP powder (100 mg) added to lipiodol and aluminum stearate as suspension following HAI. The tumor regression rate was about 60% after HAI, but the remaining tumor seemed to be almost necrotic. AFP and PIVKA-II reached the normal range after TAE. We could not find lipiodol accumulated in tumor on CT carried out eight weeks after TAE. No recurrence has been noticed in the following 8 months. Toxicity was not so severe and was well tolerated.


Growth patterns after surgery for virilising adrenocortical adenoma. Analysis of growth in nine girls after successful surgical removal of a virilising adrenocortical adenoma showed that five girls continued to grow rapidly for up to 18 months after operation and subsequently had normal growth velocities. The other four girls grew at normal rates after surgery. Only one girl showed progressive advance in bone age after operation and she subsequently had precocious puberty.


Intraoperative monitoring of an unusual brachial plexus tumor. This case illustrates the importance of intraoperative monitoring of neuronal function to help separate tumor tissue from neural tissue in a 54-year-old patient with left shoulder pain resulting from a desmoid tumor. Preoperative nerve conduction and electromyographic studies showed a lesion in the lateral cord of the brachial plexus, which was found to be intimately involved with the tumor mass and was splayed into a very thin effaced sheet of neural tissue. Stimulation of the tumor/nerve tissue mass proximal to the lesion was impossible due to the invasion of the brachial plexus by the tumor. The technique that was adapted for this unusual presentation was to stimulate the tumor/nerve tissue mass itself and record compound muscle action potentials distally. With the technique described, a subtotal resection of an aggressive fibromatosis enmeshed in the proximal brachial plexus was possible, and excellent relief of pain symptoms and retention of functional capabilities of the involved extremity were achieved.


Hydroxyapatite orbital implant after enucleation. Experience with initial 100 consecutive cases. The hydroxyapatite orbital implant is designed to provide the enucleated patient with improved motility of the prosthesis. We report the results of our first 100 consecutive cases of hydroxyapatite implantation in eyes enucleated primarily for intraocular neoplasms. During a median of 11 months' follow-up, there have been no cases of orbital infection, implant extrusion, or implant migration. Minor postoperative problems have included transient orbital pain in six patients, Tenon's fascia edema and buried peg from tissue overgrowth in two patients each, wound erosion and peg extrusion in one patient each, and audible click of the peg in three patients. Movement of the socket and fornices was excellent in 99% of patients. Motility was cosmetically satisfactory with 10 degrees to 15 degrees rapid darting prosthesis movement present in 96% of patients regardless of whether the peg had been placed. Large-degree prosthesis motility (greater than 15 degrees) was present in 24% of all patients and was most impressive in those adults who had the peg in place and in children. The hydroxyapatite implant appears to be well tolerated and provides prosthesis motility with few problems.


Demonstration of receptors for epidermal growth factor on cultured rabbit chondrocytes and regulation of their expression by various growth and differentiation factors. Epidermal growth factor (EGF) receptors were demonstrated on cultured rabbit costal chondrocytes. After crosslinking, the receptors on the cells with 125I-EGF, one major band of 170 KDa was separated by SDS-PAGE. Scatchard analysis demonstrated two classes of EGF receptors with Kd values of 0.3 nM and 1.6 nM. The numbers of high and low affinity receptors were 3,000 and 10,000 per cell, respectively. EGF receptors on chondrocytes were increased by treatment with retinoic acid and interleukin-1 beta, which inhibited proteoglycan synthesis. On the other hand, parathyroid hormone and dibutyryl cyclic AMP, which stimulated proteoglycan synthesis, decreased the number of EGF receptors. Treatments with these agents did not change the affinity of the receptors. These findings suggest that the number of EGF receptors is a negative marker of chondrocyte differentiation.


Calcium is required for the mitogenic activation of lymphocytes by periodic acid oxidation. This investigation of Ca2+ requirements for the mitogenic activation of lymphocytes by periodic acid has shown that oxidation by periodate causes an immediate and transient increase of Ca2+ influx and efflux in oxidized cells. Oxidized lymphocytes maintained in the medium containing 0.2 mM Ca2+ failed to proliferate or to produce IL-2, whereas a 1.4 mM Ca2+ concentration was shown to be sufficient to sustain cellular proliferation and IL-2 secretion. These results indicate that mitogenic activation of lymphocytes by periodic acid oxidation is Ca(2+)-dependent.


The unique N-terminal sequence of testis angiotensin-converting enzyme is heavily O-glycosylated and unessential for activity or stability. The testis-specific isozyme of angiotensin-converting enzyme (ACE) is identical, from residue 68 to the C terminus, to the second half or C-terminal domain of somatic ACE. However, the first 67 residues, comprising the signal peptide and a Ser-/Thr-rich 36-residue sequence that constitutes the N terminus of mature testis ACE, are unique. We have expressed a mutant human testis ACE lacking this 36-residue N-terminal sequence and find that compared to the wild-type protein the mutant is 15 kDa smaller due to the loss of greater than 90% of all O-linked sugars, but that it retains full enzymatic activity and is stable in culture. Heavy O-glycosylation is a property of testis ACE that is not shared by the somatic enzyme and is attributable to this unique sequence.


Creation of amyloid fibrils from mutant Asn187 gelsolin peptides. The amyloid protein in familial amyloidosis, Finnish type, is a 71 amino acid long fragment of the inner region of mutant Asp187----Asn gelsolin. The mechanism of gelsolin amyloid formation was tested with synthetic 11 and 30 residue peptides corresponding to the normal and mutant sequence of gelsolin. Fibrils meeting the morphologic criteria of amyloid were formed from the mutant Asn187 peptides. Substitution of the normal Asp187 residue with the mutant Asn residue resulted in a 9-fold increase in fibrillogenicity as determined by quantitative fluorometry. The present study demonstrates the first successful in vitro creation of amyloid-like fibrils from Asn187 gelsolin peptides and provides evidence that amyloid formation in Finnish amyloidosis is a direct consequence of the Asp187----Asn substitution in gelsolin.


Total synthesis of horse heart cytochrome C. A strategy based on complexation-assisted condensation of large synthetic protein fragments and mitochondria-mediated stereospecific heme insertion has been utilized to assemble a functional molecule corresponding to native horse heart holocytochrome c. This original approach offers the unique opportunity of selective modifications both in the C-terminal and in the N-terminal regions of the apoprotein and may represent an useful alternative to site-directed mutagenesis, particularly when D-amino acids, chemically and/or isotopically modified or other unnatural amino acids have to be introduced in this important molecule. The present result is an example of how solid phase peptide synthesis of large protein fragments in conjunction with the availability of a specific recognition process may extend the potentiality of the chemical approach to the synthesis of an entire protein.


Cloning and increased expression of an insulin receptor substrate-1-like gene in human hepatocellular carcinoma. Human insulin receptor substrate-1 (hIRS-1) cDNAs were cloned from a lambda GT11 expression library using a monoclonal antibody (MAb) produced against a human hepatocellular carcinoma (HCC) cell line (FOCUS). The predicted amino acid sequence derived from both a genomic DNA fragment and the cDNAs showed a 90.5% identity to the previously reported rat IRS-1 cDNA [Sun, X.P. (1991) Nature 352, 73-77]. Multiple potential phosphorylation sites, that suggest an intrinsic function of this molecule in response to insulin action, were highly conserved between the two species. A c.a. 180 kDa hIRS-1 protein was immunoprecipitated and found to be phosphorylated on tyrosine residue(s) following insulin stimulation of HuH-7 HCC cells. Northern blot analysis demonstrated a single c.a. 5 kb transcript in HCC cell lines and tissues. Higher levels of hIRS-1 gene transcripts were observed in HCC tumors compared to adjacent non-involved normal liver.


PAF-induced activation of polyphosphoinositide-hydrolyzing phospholipase C in cerebral cortex. The action of platelet-activating factor (PAF) on phosphoinositide hydrolysis was studied in rat brain slices. PAF produced a significant increase of 32P incorporation into phosphoinositides and phosphatidic acid (PA), in a dose- and time-dependent manner. Concomitantly, an increase of inositol phosphates and diacylglycerol (DAG) production was observed. Both inositol bisphosphate (IP2) and inositol trisphosphate (IP3) were detected as early as 5 s and they returned immediately to basal levels; concomitantly, formation of inositol monophosphate (IP) was detected. These findings demonstrated that PAF causes a rapid hydrolysis of polyphosphoinositides in cerebral cortex by a phospholipase C-dependent mechanism followed by subsequent resynthesis.


A new type of hepatitis C virus in patients in Thailand. Partial nucleotide sequences in the tentative NS5 region of the hepatitis C viral genome obtained from patients with chronic hepatitis in Thailand were analyzed by reverse transcription followed by the polymerase chain reaction. Of ten samples studied, four showed low homologies to any known type of HCV: the homologies of the nucleotide sequences of these clones with HCV-J, -US, -K2a and -K2b were 66.5-69.1%, 66.5-68.2%, 61.2-64.1% and 64.4-66.2%, respectively, and the homologies of their deduced amino acids sequences were 71.7-75.2%, 71.7-75.2%, 69.0-72.6% and 69.9-73.5%, respectively. These four clones were classified a new distinct type of HCV, named HCV-T. Moreover, the nucleotide and amino acid sequence homologies of the four HCV-T clones showed that the HCV-T type could be classified into two genotypes, HCV-Ta and HCV-Tb.


Expression of the heparin-binding growth factor receptor genes in human megakaryocytic leukemia cells. K-sam/bek, N-sam/flg and FGFR3/sam3 establish gene family of the receptors for heparin-binding growth factors (HBGFs) or FGFs. These mRNAs were detected in human leukemia cells, CMK, K562 and HEL, which have megakaryocytic phenotype or the potency to differentiate into megakaryocytic lineage. In CMK cells N-sam/flg transcript level was enhanced by the culture with 12-O-tetradecanoylphorbol-13-acetate (TPA). cDNA-polymerase chain reaction identified K-sam/bek mRNA in human platelets, suggesting the involvement of HBGFs in megakaryocytopoiesis and functions of platelets.


[Malignant fibrous histiocytoma in the area of the head and neck]. Although malignant fibrous histiocytoma (MFH) is the most common soft tissue sarcoma of adult life, it is fairly rare in the head and neck region (3-6%). Between 1983 and 1991 8 patients with MFH in the head and neck region have been observed and treated at the ENT-department of the University of Tübingen. 5 patients have been operated (laryngopharyngeal localization), 2 patients underwent irradiation (unresectable fast growing T4-tumors of the pharynx and thyroid) and one female patient refused further therapy after two resections elsewhere. Operated patients showed no evidence of disease 2-8 years after resection (all margins have been controlled histologically). Both irradiated patients died 4 respectively 2 months after full (70 Gy) and incomplete (17 Gy) radiotherapy without visible positive effects. Both patients developed pulmonary metastasis. Since MFH can grow in thin layers along musculaoponeurotic structures the exact size is not always demonstrable by ultrasound, CT or MR scans. Metastasis occur in up to 40%, preferentially in regionary lymph nodes, in lung, liver and skeletal system. These phenomenon requires a full pretherapeutic staging. Histologically MFH is sometimes hard to distinguish from other tumors as for example various sarcomas and pleomorphic carcinoma. Therefore, immunohistochemical (mesenchymal markers) and electron microscopical investigations are advised. Resection with exact histological controll of all margins is the therapy of choice. We experienced that laryngeal MFH (n = 3) can be resected without laryngectomy under certain circumstances. Although unsuccessfull in our two cases, according to the literature, radiotherapy should be administered in unresectable cases. Depending on localization and size of MFH long survival, in single cases healing, of this disease is possible by surgical treatment.


Enhanced RNase H activity with methylphosphonodiester/phosphodiester chimeric antisense oligodeoxynucleotides. Chimeric oligodeoxynucleotides, comprised of internal phosphodiester and terminal methylphosphonodiester sections, possess many beneficial characteristics as antisense effectors. We have investigated the effects of progressive replacement of phosphodiester by methylphosphonodiester linkages on hybrid stability with complementary RNA and DNA. The melting temperatures (Tms) of oligodeoxynucleotide/RNA heteroduplexes were found to decrease dramatically with increasing methylphosphonate substitution. In contrast, a smaller reduction in Tm was observed for comparable DNA heteroduplexes. This disparate reduction in hybrid stability was found with both the G + C-rich human c-myc and A + T-rich human c-Ha-ras sequences used, suggesting that methylphosphonate oligodeoxynucleotide analogues generally hybridize with less affinity to RNA than DNA. RNase H assays were employed to determine if the noted decreases in Tm impaired the ability of chimeric oligodeoxynucleotides to direct the degradation of RNA. Contrary to expectation, increasing methylphosphonate substitution gave rise to increasing rates of RNA degradation for both the c-myc and c-Ha-ras series. The present results suggest that chimeric oligodeoxynucleotide analogues may be of considerable utility as antisense agents in systems where RNase H is thought to make a major contribution to inhibition of gene expression.


Production and characterization of recombinant insulin-like growth factor-I (IGF-I) and potent analogues of IGF-I, with Gly or Arg substituted for Glu3, following their expression in Escherichia coli as fusion proteins. The development of an efficient expression system for insulin-like growth factor-I (IGF-I) in Escherichia coli as a fusion protein is described. The fusion protein consists of an N-terminal extension made up of the first 46 amino acids of methionyl porcine GH ([Met1]-pGH) followed by the dipeptide Val-Asn. The latter two residues provide a unique hydroxylamine-sensitive link between [Met1]-pGH(1-46) and the N-terminal Gly of IGF-I. Downstream processing of the fusion proteins involved isolation of inclusion bodies, cleavage at the Asn-Gly bond, refolding of the reduced IGF-I peptide and purification to homogeneity. This expression system was also used to produce two variants of IGF-I in which Glu3 was substituted by either Gly or Arg to give [Gly3]-IGF-I and [Arg3]-IGF-I respectively. Production of milligram quantities of IGF-I peptide was readily achieved. The purity of the IGF-I, [Gly3]-IGF-I and [Arg3]-IGF-I was established by high-performance liquid chromatography and N-terminal sequence analysis. [Gly3]-IGF-I and [Arg3]-IGF-I were more potent than IGF-I in biological assays measuring stimulation of protein synthesis and DNA synthesis or inhibition of protein breakdown in rat L6 myoblasts. Both analogues bound very poorly to bovine IGF-binding protein-2 and slightly less well than IGF-I to the type-1 receptor on rat L6 myoblasts. We conclude that reduced binding to IGF-binding proteins rather than increased receptor binding is the likely explanation for the greater biological potency of the analogues compared with IGF-I.


A single amino acid residue replacement in the beta subunit of human chorionic gonadotrophin results in the loss of biological activity. The heterodimer, human chorionic gonadotrophin (hCG), contains an alpha subunit that is common to the glycoprotein hormones and a hormone-specific beta subunit. A comparison of all known beta amino acid sequences shows that an aspartic acid at position 99 (with the numbering scheme for hCG-beta) is one of the seven non-Cys invariant residues. Using site-directed mutagenesis we have replaced hCG-beta Asp99 with Arg. Chinese hamster ovary cells, containing a stably integrated gene for bovine alpha subunit, were transiently transfected with plasmids containing wild-type and mutant hCG-beta cDNAs. The Arg99 beta mutant associated with the alpha subunit, but the resulting heterodimer failed to enhance intracellular cyclic AMP production in a gonadotrophin-responsive transformed murine Leydig cell line. Thus, a single amino acid residue replacement in this glycosylated heterodimer containing 237 amino acid residues is sufficient to abolish activity.


Transformed rat tracheal epithelial cells exhibit alterations in transforming growth factor-beta secretion and responsiveness. The purpose of our studies was to define abnormalities in the transforming growth factor-beta (TGF-beta) system of transformed rat tracheal epithelial (RTE) cells that might cause their abnormal growth behavior. We found that many, but not all, of the transformed cell lines were hyporesponsive or unresponsive to the growth inhibitory effects of TGF-beta 1. Scatchard and receptor cross-linking analyses indicated that loss of TGF-beta 1 responsiveness of transformed cells was probably not due to changes in receptor number or affinity, or to changes in expression of the three TGF-beta-binding protein subtypes. Transformed cells were found to secrete far less TGF-beta-like activity (less than 1/10) than primary cells. Cultured normal and transformed RTE cells expressed three TGF-beta 1 transcripts of 2.5, 1.9, and 1.4 kb. In contrast, rat kidney tissue, a rat embryo fibroblast cell line, and a rat liver cell line expressed only the typical 2.5-kb mRNA transcript commonly reported in the literature. In spite of the marked differences in TGF-beta secretion between normal and transformed cells, their levels of TGF-beta 1 mRNA expression were similar. This suggests a change in the posttranscriptional regulation of TGF-beta 1 expression. TGF-beta 2 message was not detected in either normal or transformed RTE cells in culture. These findings are consistent with the hypothesis that the abnormal growth behavior of transformed RTE cells is at least in part due to disturbances of the TGF-beta system.


Cytoreductive therapy of multidrug-resistant hepatocellular carcinoma: negative regulation of growth using combination differentiation therapy. In vitro studies of the mouse erythroleukemia cell system have identified at least 300 agents capable of inducing differentiation by mechanisms that remain to be elucidated. We have recently begun to examine recombinant cytokines as possible agents in inducing differentiation of tumor cells, specifically, malignant cells resistant to cytotoxic drugs. One such cytokine, transforming growth factor-beta (TGF-B1), is a multifunctional peptide that exists in at least five different isoforms in vertebrate species. Recently, there has been a great deal of interest in the role of TGF-B1 as an important multifunctional growth regulator that induces cells of mesenchymal origin to divide while inhibiting the growth of nontransformed epithelial cells. In this study, we combined the effects of the differentiation agent hexamethylene bisacetamide and the inhibiting effects of TGF-B1 on a multidrug-resistant human liver hepatocellular carcinoma and demonstrated the synergistic interaction of these two agents; this synergy resulted in a cell death rate of 80%. These data support the concept of programmed cell death and suggest that drug-resistant tumor cells may be susceptible to the combination of cytokines and differentiating agents.


HIV seropositivity in community-recruited and drug treatment samples of injecting drug users. To assess the representativeness of drug use treatment samples for measuring HIV seroprevalence among injecting drug users (IDU) in community settings. Seroprevalence was determined in two cross-sectional, convenience samples including an unlinked survey of IDU entrants to all publicly-funded drug-treatment programs and a survey of community-recruited IDU. Unconditional logistic regression [odds ratio (OR)] was used to calculate unadjusted and adjusted OR to measure the association between HIV seropositivity and site of recruitment. Between 1988 and 1989, 25% of 870 community-recruited IDU were seropositive, compared with 13% of 671 entrants to drug-treatment programs. This twofold risk of HIV seropositivity among community-recruited IDU remained after adjustment for sample differences in gender, race-ethnicity, and age group (adjusted OR, 2.09; 95% confidence interval, 1.58-2.78). These results suggest the importance of extending HIV surveillance outside of drug-treatment facilities. Active serologic surveillance may be feasible by coupling recent saliva and fingerstick sampling techniques with existing community outreach education efforts.


Inactivation of Ca current during the action potential in guinea-pig ventricular myocytes. The inactivation of Ca channels during the action potential plateau of guinea-pig ventricular myocytes was investigated by interrupting action potentials with voltage clamp pulses to assess Ca channel availability. The influence of the bulk cytosolic calcium [( Ca]i) transient on Ca channel inactivation was also studied by impaling cells with microelectrodes containing the Ca chelator BAPTA (1,2 bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid; 125-200 mM). Ca channel availability decreased progressively with action potential duration, reaching approximately 20% of maximum availability after 100 ms and falling close to zero at the end of the plateau. When membrane potential became more negative than -40 mV Ca channel availability increased. Elevation of the action potential plateau to more positive levels increased Ca channel availability (even though this was expected to increase peak [Ca]i). When the cytosol was loaded with BAPTA Ca channel availability during the plateau increased. Inactivation of Ca channels was not, however, abolished. The observations are consistent with the hypothesis that in guinea-pig ventricular myocytes the majority of Ca channels are inactivated during the plateau and recovery does not occur until repolarization is almost complete. It may be that while the cytosolic Ca transient (that is generated in part by release of Ca from the intracellular Ca stores) modulates Ca channel availability, significant inactivation of the Ca channel during the action potential plateau is due to voltage dependent inactivation and to Ca-induced inactivation resulting from the Ca which enters the myocyte via Ca channels.


Intracellular pH changes induced by hypoxia and anoxia in isolated sheep heart Purkinje fibres. The effects were studied of hypoxia on intracellular ion activities in sheep heart Purkinje fibres. The intracellular pH (pHi), surface pH (pHs), intracellular potassium activity (aki), and intracellular sodium activity (aNai) of the cells were recorded using liquid ion exchanger-filled microelectrodes. Various methods of inhibiting oxidative phosphorylation were compared for their effect on pHi. These methods were the use of hypoxia, anoxia or NaCN (2 mM). Hypoxia was produced by degassing solutions under reduced pressure then bubbling with 100% nitrogen gas. Anoxia was produced in a similar manner but with the addition of the reducing agent sodium dithionite (0.5 mM) to remove all traces of oxygen from the solutions. Anoxia caused the most marked changes. Concentration of sodium dithionite between 0.1 and 1 mM produced similar maximum rates of acidification. High concentrations (5 or 20 mM) could produce larger intracellular acidifications apparently unrelated to anoxia. The effects of hypoxia and NaCN were similar. Inhibition of Na(+)-H+ exchange with amiloride (1 mM) had little effect on the pH changes produced by hypoxia. Periods of hypoxia exceeding 1 h still resulted in rapid, readily reversible changes in pHi. Hypoxia caused a rise in aNai, the effect being larger in anoxic conditions. The intracellular K+ activity decreased in hypoxia with further decreases in anoxic conditions. The intracellular ion changes produced during hypoxia are discussed in terms of the production of lactic acid by the cells and changes in the ATP supply to the Na(+)-K+ pump.


Calcium oscillations in single isolated human vascular smooth muscle cells. When cultured human vascular smooth muscle cells are exposed to sodium-free solutions oscillations in intracellular calcium concentration are observed. In some cells the oscillations are maintained at constant amplitude throughout the exposure to Na(+)-free solution, in others the amplitude of the oscillations falls to a lower, steady-state level. The oscillations are also activated and maintained in isotonic, Na(+)-free, K+ solutions suggesting that the underlying mechanism does not involve the opening and closing of voltage-dependent channels. The possible mechanisms responsible for this behaviour are discussed.


HIV-related risk behaviors among cocaine users. Risk behaviors related to human immunodeficiency virus (HIV) infection and transmission were studied in a sample of 167 male cocaine users admitted during a 5-month period to an inpatient drug treatment program. Data obtained included drug history and related behaviors, sexual behaviors, knowledge, and attitudes regarding HIV infection and AIDS. Approximately 20% of the sample had used IV drugs in the year prior to the interview and 94% of these reported sharing needles; 20% of the IV drug users (IVDUs) reported always using bleach to clean needles. With regard to sexual practices, 7% of the total sample reported sex with other males in the year prior to the interview; 86% of the total sample reported having sex with females and 80% of these noted they never or rarely used condoms during vaginal sex. Respondents generally did not believe they themselves were at high risk for HIV infection, yet they continued to engage in acknowledged high-risk behaviors. These findings suggest that IVDUs and non-IV cocaine users are likely to contribute to the spread of HIV in several populations.


Decreased plasma superoxide scavenging activity in immunological disorders--carboxyethylgermanium sesquioxide (Ge-132) as a promoter of prednisolone. We investigated so-called superoxide scavenging activity (SSA) of plasma in patients with several immunological disorders, such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), polymyo-dermatomyositis (PM), progressive systemic sclerosis (PSS), myasthenia gravis (MG) and autoimmune thyroid disease (AT), using the electron paramagnetic resonance/spin trapping technique. Since carboxyethylgermanium sesquioxide, Ge-132, has been reported to modulate both the immune response and leukocyte functions, we have studied in vivo effect of Ge-132 on plasma SSA and other laboratory parameters in these disorders. The plasma SSA was significantly lower in RA, SLE, PM and PSS, but not in MG and AT, as compared with that in healthy controls. An inverse correlation was observed between plasma SSA and parameters such as erythrocytes sedimentation rates, absolute number of leukocytes, C-reactive protein and serum globulin levels. Furthermore, plasma SSA was significantly decreased in rheumatoid factor-positive patients as compared to negative patients. No correlation was observed between plasma SSA and factors such as ages, sex of patients or the other laboratory parameters, such as serum albumin, triglyceride, cholesterol, hemoglobin and serum iron levels. Patients treated with prednisolone, especially ones with RA, showed an increase of plasma SSA. It appears that Ge-132 promotes prednisolone effects. Our results indicate that a decrease in plasma SSA is not disease specific, but inversely correlates with the severity and activity of inflammation. The methodology to measure plasma SSA presented in this work provides a helpful tool for determining the actual activity of the diseases as well as in vivo studies of antiinflammatory agents.


Azoles, allylamines and drug metabolism. Four antifungal drugs, the azoles ketoconazole, itraconazole and fluconazole, and the allylamine terbinafine, were studied for their effects on the metabolism of cyclosporin A (CyA) and cortisol by human liver microsomes in vitro (n = 3). Ketoconazole produced marked inhibition of CyA hydroxylase (to metabolites M17 and M1) with IC50 and Ki values of 0.24 +/- 0.01 and 0.022 +/- 0.004 microM, respectively. On the basis of the IC50, itraconazole was 10 times less potent (IC50 of 2.2 +/- 0.2 microM), and fluconazole and terbinafine were each above 100 microM. No kinetic parameters were calculated for terbinafine because of the lack of inhibitory effects. Ketoconazole was the most potent inhibitor of cortisol metabolism (to 6 beta-hydroxycortisol, IC50 = 0.6 microM). Itraconazole produced marked inhibition of cortisol metabolism (IC50 = 2.4 microM), but fluconazole and terbinafine had little effect. These data confirm that ketoconazole is a potent inhibitor of cytochrome P-450-IIIA4, and this has clinical relevance. Although the inhibition with fluconazole was much less than with itraconazole at equimolar concentrations, it should be noted that in-vivo plasma concentrations of fluconazole are much greater than that of itraconazole. Clinical interactions of CyA with both fluconazole and itraconazole have been reported; in contrast to these azoles, terbinafine does not have the same interaction potential.


Clinical significance of interactions with antifungal agents. Antifungal drugs act by a variety of mechanisms. Agents such as substituent imidazoles and triazoles, which act by inhibiting the fungal cytochrome P-450-dependent enzyme lanosterol N-demethylase, have the potential to inhibit host cytochrome P-450-dependent drug metabolism. This is discussed with respect to ketoconazole, fluconazole and itraconazole. In contrast, allylamines, which have a different mode of action and a weaker ability to bind to cytochrome P-450, are not expected to inhibit clinical drug oxidation. Inducers of drug metabolism, especially rifampicin, phenobarbitone and phenytoin, may lower plasma (and tissue) concentrations of those antifungals metabolized by mixed function oxidases, with therapeutic consequences.


Inhibition of cyclic AMP- and cyclic GMP-mediated dilations in isolated arteries by oxidized low density lipoproteins. We studied the effects of native (N) and oxidized (Ox) low density lipoproteins (LDLs) on adenosine 3',5'-cyclic monophosphate (cAMP)-mediated and on guanosine 3',5'-cyclic monophosphate (cGMP)-mediated dilator mechanisms in isolated, perfused human mammary and rabbit femoral arteries. Dilations were induced in preconstricted, deendothelialized segments by either forskolin (Fo) or sodium nitroprusside (SNP) (intraluminal or adventitial application). Lipoproteins (0.5 mg/ml) were administered to the segments from the intraluminal side. N-LDL had no effect on Fo-induced dilation and caused a weak attenuation of SNP-induced dilation only when SNP was also administered into the intraluminal perfusate. In contrast, Ox-LDL inhibited both Fo- and SNP-induced dilation, independent of the route of dilator application. The effects of Ox-LDL were specific for dilation mediated by cyclic nucleotides. Dilation elicited by the Ca2+ antagonist nitrendipine was inhibited neither by N-LDL nor by Ox-LDL. Determination of basal and stimulated (SNP, Fo) cGMP and cAMP content in rabbit femoral segments after preincubation with N-LDL and Ox-LDL revealed a significant decrease of stimulated vascular cGMP and cAMP content by Ox-LDL, whereas N-LDL had no effect. These data indicate that Ox-LDL selectively inhibits vascular smooth muscle relaxation elicited by increases in cyclic nucleotides. This inhibition might contribute to the attenuation of vasodilation in hypercholesterolemia and atherosclerosis.


Antithrombotic efficacy of low-molecular-weight heparin in deep arterial injury. Low-molecular-weight heparin subfractions more specifically inhibit factor Xa than thrombin, and they may have advantages over unfractionated heparin in arterial thrombosis. The antithrombotic efficacy of four dosages of a low-molecular-weight heparin (CY216 at 100, 200, 400, or 500 Institute Choay units/kg) was compared with unfractionated calcium heparin (100 US Pharmacopeia units/kg) and placebo during deep arterial injury produced by balloon dilatation of the carotid artery in the pig. The acute thrombotic end points were 111In-labeled platelet and 125I-labeled fibrinogen/fibrin deposition and macroscopic mural thrombosis; these were related to the anti-factor Xa and antithrombin effects of the heparin preparations. Platelet deposition in segments with deep arterial injury was 42 +/- 28, 22 +/- 5, 29 +/- 12, 9 +/- 2, 9 +/- 2, and 11 +/- 3 x 10(6)/cm2 (mean +/- SEM) for pigs treated with placebo, with 100, 200, 400, and 500 units/kg CY216, and with 100 units/kg unfractionated heparin, respectively. Fibrinogen/fibrin deposition was 35 +/- 8, 19 +/- 2, 19 +/- 4, 21 +/- 3, 14 +/- 4, and 12 +/- 3 molecules x 10(12)/cm2, respectively; deposition was significantly reduced in pigs given 100 units/kg unfractionated heparin compared with placebo (p less than 0.05). Mural thrombosis was present in 74%, 45%, 30%, 14%, 5%, and 9% of deeply injured arterial segments, respectively (p = 0.02). Plasma anti-factor Xa activity and prolongation of the activated partial thromboplastin time (aPTT) with 100 units/kg unfractionated heparin were similar to that produced by 200 units/kg and 500 units/kg CY216, respectively. Thus, low-molecular-weight heparin, which predominantly inhibits factor Xa activity, was only moderately effective at reducing platelet thrombus deposition. It was less effective than 100 units/kg unfractionated heparin, except at high dosages, producing similar prolongation of the aPTT and the thrombin time.(ABSTRACT TRUNCATED AT 250 WORDS)


Does the EcoRI polymorphism in the human apolipoprotein B gene affect the binding of low density lipoprotein to the low density lipoprotein receptor? In human populations, there is an association between coronary artery disease and a polymorphism in the apolipoprotein B (apo B) gene detected with the enzyme EcoRI. This polymorphism gives rise to two apo B alleles, one (E+) encoding glutamic acid and the other (E-) encoding lysine at position 4,154 in apo B-100, the protein of low density lipoprotein (LDL). We have tested the hypothesis that this amino acid substitution indirectly influences proneness to coronary artery disease by affecting the binding of LDL to LDL receptors. The receptor-binding affinities of LDLs from eight pairs of subjects with genotypes E+/+ and E-/- who were matched for other apo B genotypes were determined in vitro. There was no significant difference between the binding affinities of LDLs from the two groups of subjects. Our results strongly suggest that the amino acid at position 4,154 does not influence the function of the receptor-binding domain in apo B-100 and that the association between coronary artery disease and the EcoRI polymorphism is not mediated by an effect of the polymorphism on serum LDL concentration. In view of our findings, it would be of interest to examine the effect of the amino acid substitution on the binding of LDL to arterial proteoglycans and on the oxidizability of LDL by cells in culture.


Isoforms of cytochrome c oxidase in tissues and cell lines of the mouse. The subunit pattern of immunopurified cytochrome c oxidase from cultured mouse cells and mature tissues of the mouse was investigated by electrophoretic analysis. In mature tissues two forms of cytochrome c oxidase could clearly be identified on the basis of differences in morbidity or staining intensity of subunits VIa and VIII. One form was present in muscle and heart, and the other in liver, kidney and spleen. In lung both forms were found. In the thymus, subunit VIII showed the characteristics of subunit VIII found in muscle and heart, whereas subunit VIa resembled subunit VIa found in liver. This suggest the existence of a third cytochrome c oxidase isoform. The subunits of cytochrome c oxidase from cultured cell lines showed no differences between the various cell lines and resembled those of mature mouse liver tissue. The cytochrome c oxidase isoform from cultured proliferating cells might therefore be the same as the one found in liver. Alternatively, it might represent either a normally occurring fetal isoform, or a form specific for poorly differentiated cultured cells.


Formation of supported planar bilayers by fusion of vesicles to supported phospholipid monolayers. A technique for the production of supported phospholipid bilayers by adsorption and fusion of small unilamellar vesicles to supported phospholipid monolayers on quartz is described. The physical properties of these supported bilayers are compared with those of supported bilayers which are prepared by Langmuir-Blodgett deposition or by direct vesicle fusion to plain quartz slides. The time courses of vesicle adsorption, fusion and desorption are followed by total internal reflection fluorescence microscopy and the lateral diffusion of the lipids in the adsorbed layers by fluorescence recovery after photobleaching. Complete supported bilayers can be formed with phosphatidylcholine vesicles at concentrations as low as 35 microM. However, the adsorption, fusion and desorption kinetics strongly depend on the used lipid, NaCl and Ca2+ concentrations. Asymmetric negatively charged supported bilayers can be produced by incubating a phosphatidylcholine monolayer with vesicles composed of 80% phosphatidylcholine and 20% phosphatidylglycerol. Adsorbed vesicles can be removed by washing with buffer. The measured fluorescence intensities after washing are consistent with single supported bilayers. The lateral diffusion experiments confirm that continuous extended bilayers are formed by the monolayer-fusion technique. The measured lateral diffusion coefficient of NBD-labeled phosphatidylethanolamine is (3.6 +/- 0.5) x 10(-8) cm2/s in supported phosphatidylcholine bilayers, independent of the method by which the bilayers were prepared.


CDP-choline: 1,2-diacylglycerol cholinephosphotransferase from rat liver microsomes. II. Photoaffinity labeling by radioactive CDP-choline analogs. Photoaffinity labeling of cholinephosphotransferase from rat liver microsomes directly by its substrate, [32P]CDP-choline or by a synthetic photoreactive CDP-choline analog, 3'(2')-O-(4-benzoyl)benzoyl [32P]CDP-choline (BB-[32P]CDP-choline), was examined for the possible identification of its molecular form on subsequent SDS-PAGE followed by 32P-autoradiography. When the partially purified cholinephosphotransferase was photoirradiated in the presence of [32P]CDP-choline, a considerable amount of 32P-radioactivity was incorporated into the TCA-insoluble component. This incorporation was dependent on irradiation time, Mg2+ or Mn(2+)-requiring and inhibited strongly by the presence of Ca2+. Either CDP-choline or CDP-ethanolamine inhibited the ultraviolet irradiation-dependent incorporation of 32P-radioactivity into the TCA-insoluble component in a dose-dependent manner, whereas neither phosphocholine or 5'-CDP had any effect on this process. These results strongly suggested that the observed 32P-incorporation from [32P]CDP-choline into the protein component could be a consequence of the covalent interaction between cholinephosphotransferase and its substrate, [32P]CDP-choline. Two polypeptides, 25 kDa and 18 kDa, with high 32P-radioactivity were clearly identified on a SDS gel after the direct photoaffinity labeling with [32P]CDP-choline for more than 5 min of ultraviolet irradiation. On the other hand, when BB-[32P]CDP-choline was used as a photoaffinity ligand, a single polypeptide with apparent molecular size of 55 kDa could be rapidly photolabeled within 2.5 min, then this band gradually lost its 32P-radioactivity with increasing time of ultraviolet irradiation. Thus, the overall results strongly indicated that cholinephosphotransferase in rat liver microsomes exists most likely as a 55 kDa polypeptide (or subunit) and that 25 kDa and 18 kDa peptides identified after the direct photoaffinity labeling with [32P]CDP-choline were probably the photo-cleavage products of cholinephosphotransferase during the prolonged ultraviolet irradiation, both of which could contain the catalytic domain of the original enzyme protein(s).


Soybean phospholipid dependent reductions in triacylglycerol concentration and synthesis in the liver of fasted-refed rats. The effect of dietary soybean phospholipid on the activities of hepatic triacylglycerol-synthesizing enzymes was compared with soybean oil in fasted-refed rats. Soybean oil at the dietary level corresponding to 20% but not at 5% fatty acid level (21.2 and 5.3% on weight bases, respectively) significantly decreased liver microsomal diacylglycerol acyltransferase activities measured with the endogenous diacylglycerol substrate. Dietary soybean phospholipid even at the dietary level corresponding to 2% fatty acids (3.4% on weight base) significantly decreased the acyltransferase activities measured with endogenous substrate. The dietary phospholipid further decreased the parameter as the dietary level increased, and at the 5% fatty acid level, it was lower than that obtained with soybean oil at 20% fatty acid level. Soybean oil and phospholipid decreased the diacylglycerol acyltransferase activities measured with the saturating concentration of exogenous dioleoylglycerol substrate only when the activities were expressed in terms of total activity (mumol/min per liver) but to much lesser extents. Dietary phospholipid compared to the oil profoundly decreased not only hepatic triacylglycerol but also microsomal diacylglycerol levels. It was indicated that the availability of microsomal diacylglycerol as the substrate for diacylglycerol transferase is the critical determinant in regulating hepatic triacylglycerol synthesis and concentration in this experimental situation. Alterations in the activities of microsomal glycerol 3-phosphate acyltransferase and of the enzymes in fatty acid synthesis could account for the phospholipid-dependent decrease in the microsomal concentration of this intermediate in triacylglycerol synthesis.


Correlation between intracellular cAMP levels and phospholipids of Microsporum gypseum. Atropine, a modulator of cAMP has been used to examine the relationship between phospholipids and intracellular levels of cAMP in Microsporum gypseum. A decreased phospholipid content was observed in atropine grown cells as a result of reduced levels of intracellular cAMP. This decline was caused by the inhibitory effect of atropine on adenylate cyclase. Lowered phospholipid content was supported by decreased [14C]acetate incorporation as well as reduced activities of key enzymes of phospholipid biosynthesis. In vitro supplementation of atropine in control cells also caused inhibition in lipid synthesis indicating similar effects of atropine and its metabolites. These results in conjunction with our previous report, in which enhanced levels of cAMP resulted in increased phospholipid synthesis, suggest a direct correlation between phospholipid biosynthesis and intracellular levels of cAMP in M. gypseum.


Mammalian protein serine/threonine phosphatase 2C: cDNA cloning and comparative analysis of amino acid sequences. Complementary DNA encoding rat protein phosphatase 2C alpha was obtained from a liver library and used to isolate the homologous cDNAs from rabbit liver and human teratocarcinoma libraries. The amino acid sequences of the three enzymes deduced from the cDNA (382 amino acids) were extremely similar (greater than 99% identity), the maximum number of differences (between rat and human) being four. Amino acid sequences of peptides corresponding to 238 residues (61%) of the protein phosphatase 2C beta isoform from rabbit skeletal muscle were determined and showed 12 differences from the recently published sequence of the rat liver enzyme deduced from the cDNA (95% identity).


Cloning of the human activin receptor cDNA reveals high evolutionary conservation. The entire coding region of the human activin receptor was obtained from a human testis cDNA library. Analysis of the 1539 nucleotide (513 amino acid) sequence of the receptor reveals that there are only 83 nucleotide differences compared to the coding sequence of the mouse activin receptor. Similar to its ligands, the amino acid sequence of the activin receptor is highly conserved with only two conservative amino acid differences (Lys-39 and Val-92 in human versus Arg-39 and Ile-92 in the mouse). This high degree of conservation of the activin receptor illustrates a strong evolutionary selection and confirms that activin and its receptor play an important role in development.


Regulation of the Escherichia coli lac operon expressed in human cells. We have investigated the use of various Epstein-Barr virus (EBV)-based vectors bearing the two components of the Escherichia coli lac operator-repressor (lacO, lacI) complex. Our aim was to develop a model system of gene expression by looking at the transcription of the bacterial beta-galactosidase coding gene (lacZ) in 293 human embryonic kidney cells. Several vectors have been built carrying different promoters upstream of the lacI and lacZ genes and in which natural or synthetic operator sequences were inserted in the 5' part of the lacZ gene. In transient expression assays we achieved efficient lacZ gene repression which could be released by the specific inducer isopropyl beta-D-thiogalactoside (IPTG). A stable transformed cell line carrying two EBV-derived plasmids with the building blocks of the lac operator/repressor system was established. This cell line allowed us to achieve a wide range of lacZ gene regulation. In this cell line IPTG alone could remove the repression to trigger a 5-fold increase of lacZ expression. Heavy metal ions, which induced the mouse metallothionein I promoter located upstream of the lacZ gene, added together with IPTG gave rise to a 40-fold induction of lacZ expression.


Interleukin 1 and phorbol 12-myristate 13-acetate induce collagenase and PGE2 production through a PKC-independent mechanism in chondrocytes. In the present study we demonstrate that interleukin 1 (IL 1) and phorbol 12-myristate 13-acetate (PMA) stimulate collagenase production by bovine chondrocytes in monolayer culture. Since it has been well established that PMA stimulates protein kinase C (PKC), we examined whether IL 1 and PMA also stimulate PKC in chondrocytes. In agreement with other studies, PMA induced the translocation of PKC, reflecting PKC activation by PMA. In contrast, IL 1 did not induce the translocation of PKC. Both IL 1 and PMA stimulated the release of [14C]arachidonic acid from chondrocyte phospholipids, suggesting that both agents stimulate phospholipase A2 (PLA2). Concomitantly, IL 1 and PMA also induced a pronounced increase in the production of PGE2. Pre-incubation of chondrocytes with staurosporine, a PKC inhibitor, did not affect the stimulation of collagenase production by IL 1 and only minimally that induced by PMA. Similarly, high concentrations of staurosporine did not inhibit prostaglandin E2 (PGE2) production induced by IL 1 or PMA. These data show that IL 1 and PMA stimulate the PLA2 pathway and collagenase production, however, these processes can occur in the absence of PKC activation.


Mechanisms by which extracellular ATP and UTP stimulate the release of prostacyclin from bovine pulmonary artery endothelial cells. Extracellular ATP and UTP caused increases in the concentration of cytoplasmic free calcium ([Ca2+]i) and the intracellular level of inositol 1,4,5-trisphosphate (IP3), a second messenger for calcium mobilization, prior to the release of prostacyclin (PGI2) from cultured bovine pulmonary artery endothelial (BPAE) cells. The agonist specificity and dose-dependence were similar for nucleotide-mediated increases in IP3 levels, [Ca2+]i and PGI2 release. An increase in [Ca2+]; and PGI2 release was observed after addition of ionomycin, a calcium ionophore, to BPAE cells incubated in a calcium-free medium. The addition of ATP to the ionomycin-treated cells caused no further increase in [Ca2+]i or PGI2 release. The inability of ATP to cause an increase in [Ca2+]i or PGI2 release in ionomycin-treated cells was apparently due to the ionomycin-dependent depletion of intracellular calcium stores since the subsequent addition of extracellular calcium caused a significant increase in both [Ca2+]i and PGI2 release. Introduction of BAPTA, a calcium buffer, into BPAE cells inhibited ATP-mediated increases in [Ca2+]i and PGI2 release, further evidence that PGI2 release is dependent upon an increase in [Ca2+]i. The increase in [Ca2+]i elicited by ATP apparently caused the activation of a calmodulin-dependent phospholipase A2 since trifluoperazine, an inhibitor of calmodulin, and quinacrine, an inhibitor of phospholipase A2, prevented the stimulation of PGI2 release by ATP. Furthermore, ATP caused the specific hydrolysis of [14C]arachidonyl-labeled phosphatidylcholine and the generation of free arachidonic acid, the rate-limiting substrate for PGI2 synthesis, prior to the release of PGI2 from BPAE cells. These findings suggest that the increase in PGI2 release elicited by ATP and UTP is at least partially dependent upon a phospholipase C-mediated increase in [Ca2+]i and the subsequent activation of a phosphatidylcholine-specific phospholipase A2. ATP analogs modified in the adenine base or phosphate moiety caused PGI2 release with a rank order of agonist potency of adenosine 5'-O-(2-thiodiphosphate) (ADP beta S) greater than 2-methylthioATP (2-MeSATP) greater than ATP, whereas alpha, beta methyleneATP and beta, gamma methyleneATP had no effect on PGI2 release.


Release of carrot plasma membrane-associated phosphatidylinositol kinase by phospholipase A2 and activation by a 70 kDa protein. Plasma membranes were isolated from carrot (Daucus carota L.) cells grown in suspension culture and treated with phospholipase A2 from snake or bee venom for 10 min. As a result of this treatment, phosphatidylinositol kinase activity was recovered in the soluble fraction. There was no detectable diacylglycerol kinase or phosphatidylinositol monophosphate kinase activity released from the membranes after the phospholipase A2 treatment. Treating the plasma membranes with phospholipase C or D did not release PI kinase activity. The phospholipase A2-released PI kinase was activated over 2-fold by a heat stable, soluble 70 kDa protein. The partially purified 70 kDa activator increases the Vmax but does not affect the Km of the phospholipase A2-released PI kinase.


Prevalence of hepatitis C antibodies (HCV) in a dialysis population at one center. Hepatitis C (HC) has been recently diagnosed by determination of specific antibodies that represent the former so-called non-A, non-B hepatitis. We studied the prevalence of plasma HCV antibodies among 61 unselected patients on hemodialysis (HD) and 43 on continuous ambulatory peritoneal dialysis (CAPD). Plasma C-antibodies were determined through the ELISA test system. Transfusion policy was the same in both groups. The prevalence of hepatitis C virus antibodies was significantly higher in hemodialysis patients than among those on CAPD. Time on dialysis, previous blood transfusions, and renal transplantation seem to increase the prevalence of C hepatitis antibodies among hemodialysis patients. The effect of these parameters on CAPD was smaller. Understanding the reasons for these differences may help prevent this disease among dialysis patients.


The prevalence of hepatitis C virus antibodies in patients treated with continuous ambulatory peritoneal dialysis. To assess the prevalence of anti-HCV (hepatitis C virus antibodies) in continuous ambulatory peritoneal dialysis (CAPD) patients and staff members. Fifty-nine serum samples were collected and tested by an enzyme immunoassay for anti-HCV. Records and past history of blood transfusion and hemodialysis were reviewed. Results were analyzed using the Fisher's exact test. A medical college-operated teaching hospital. Fifty-two patients and 7 staff members from the Chang Gung Memorial Hospital CAPD unit were studied. Anti-HCV prevalence in patients and staff were 15.4% and 0%. A history of maintenance hemodialysis was associated with a higher prevalence of anti-HCV (33.3% versus 5.9% without hemodialysis, p = 0.015). The prevalence of anti-HCV did not increase with longer CAPD duration. Among those with an episode of hepatitis, higher prevalence of anti-HCV was observed (57.1% versus 8.9% without hepatitis, p = 0.0073). HCV is an important agent of hepatitis in CAPD patients. The risk of HCV infection among CAPD staff members is negligible. CAPD offers better control of HCV infection among patients with end-stage renal failure.


Neuroendocrine and behavioral responses to challenge with the indirect serotonin agonist dl-fenfluramine in adults with obsessive-compulsive disorder. Neuroendocrine and behavioral responses to a single 60-mg oral dose of the indirect serotonin agonist dl-fenfluramine were assessed in unmedicated adults with obsessive-compulsive disorder (OCD) and neuroendocrine results contrasted with those in normal control subjects. Net fenfluramine-induced prolactin release did not differ significantly between OCD patients and normal controls. Prolactin responses in the OCD group were not significantly correlated with baseline Yale-Brown Obsessive Compulsive Scale scores for either obsessions or compulsions, but were positively correlated with the baseline Hamilton Depression Scale score and Hamilton Anxiety Scale score. No clear difference in the severity of patients' obsessions or compulsions was found following challenge with fenfluramine versus placebo. Although the present study does not demonstrate a serotonergic abnormality in OCD, this may be more a reflection of limitations of the test procedures than evidence that central nervous system (CNS) serotonergic function is normal in the disorder.


Genital papillomavirus infection in women treated for chlamydial infection. Samples for chlamydia testing were taken from 298 and PAP smear from 284 non-pregnant sexually active young women in a midwife-run family planning dervice. Chlamydia was found in 36 (12.1%). Three women (1.1%) had cytological atypia corresponding to CIN I or II. Koilocytosis was seen in 9 smears (2.8%). Thirty-two of the chlamydia-positive women were followed for a mean of 15 months by a gynaecologist with chlamydia tests, colposcopy, PAP-smears and in some cases biopsies. There were 7 reinfections with chlamydia (22%). Signs of genital papillomavirus infection (GPVI) were found in 24 of the 32 chlamydia cases during follow-up. Twenty chlamydia-positive patients had abnormal colposcopy, 15 of them had other changes suggestive of GPVI, seven of these had CIN I or II. At follow-up 6 patients had cytologic atypia (18.8%) compared with the average 1.5% in this department during this period. Among 12 patients with normal colposcopy there were no cytological changes. Chlamydial infection calls for increased alertness regarding abnormal vaginal cytology even among young patients not commonly included in PAP smear screening programmes.


Early-stage squamous cell and adenocarcinoma of the cervix. Articles on early-stage squamous cell and adenocarcinoma of the cervix published between August 1990 and July 1991 are reviewed. A new monoclonal antibody used to distinguish endocervical from endometrial differentiation is described, as well as a histochemical means of distinguishing in situ from invasive adenocarcinoma. In vitro and in vivo studies of cell lines immortalized with human papillomavirus DNA are described with a discussion of the mechanism of the development of malignancy. An animal model to test and develop an anti-human papillomavirus vaccine is presented. The epidemiology of adenocarcinoma is also reviewed, and the development of invasive carcinoma after conservative therapy or conization for dysplasia is discussed. Computed tomography scanning has been found to be no more accurate than examination for staging of early cervical cancer. Several studies in the review period have evaluated risk factors for recurrent disease in patients treated for early-stage cervical cancer, including a prospective surgical pathologic study by the Gynecologic Oncology Group. The optimal treatment of early stage I adenocarcinoma of the cervix is discussed, comparing the efficacy of primary surgical therapy with the efficacy of radiation therapy. The risk of ovarian metastases in patients with early-stage cervical cancer is very low for both squamous cell and adenocarcinoma. The surgical technique and efficacy of laparoscopic pelvic lymphadenectomy for patients with early-stage cervical cancer are discussed. Lateral transposition of the ovaries at the time of radical hysterectomy for cervical cancer has significant potential benefits but also risks. Finally, surveillance methods that detect recurrent cervical cancer after treatment for early-stage disease are discussed.


DNA insertions distinguish the duplicated renin genes of DBA/2 and M. hortulanus mice. In a survey of inbred and wild mouse DNAs for genetic variation at the duplicate renin loci, Ren-1 and Ren-2, a variant Not I hybridization pattern was observed in the wild mouse M. hortulanus. To determine the basis for this variation, the structure of the M. hortulanus renin loci has been examined in detail and compared to that of the inbred strain DBA/2. Overall, the gross features of structure in this chromosomal region are conserved in both Mus species. In particular, the sequence at the recombination site between the linked Ren-1 and Ren-2 loci was found to be identical in both DBA/2 and M. hortulanus, indicating that the renin gene duplication occurred prior to the divergence of ancestors of these mice. Renin flanking sequences in M. hortulanus, however, were found to lack four DNA insertions totaling approximately 10.5 kb which reside near the DBA/2 loci. The postduplication evolution of the mouse renin genes is thus characterized by a number of insertion and/or deletion events within nearby flanking sequences. Analysis of renin expression showed little or no difference between these mice in steady state renin RNA levels in most tissues examined, suggesting that these insertions do not influence expression at those sites. A notable exception is the adrenal gland, in which DBA/2 and M. hortulanus mice exhibit different patterns of developmentally regulated renin expression.


Relationship between intensity of Opisthorchis viverrini infection and hepatobiliary disease detected by ultrasonography. Twenty-four locality-, age- and sex-matched groups of village residents with no light, moderate and heavy Opisthorchis viverrini infection were examined by ultrasonography. Highly significant differences were observed between the groups in the relative size of the left lobe of the liver and the fasting and post-meal size of the gall-bladder. In addition, indistinct gall-bladder wall, the presence of gall-bladder sludge and strongly enhanced portal vein radicle echoes were most frequently observed in the heavily infected group. Two suspected cases of cholangiocarcinoma were identified from the heavy group. The results highlight the importance of intensity of infection on the frequency and severity of fluke-associated hepatobiliary disease.


Identification of transcriptional regulatory activity within the 5' A-type monomer sequence of the mouse LINE-1 retroposon. LINE-1 (L1) is a retroposon found in all mammals. In the mouse, approximately 10% of L1 elements are full-length and can be grouped into two classes, A or F, based upon the type of monomer sequence repeated at the 5' end. In order to test for promoter activity in the 5' end of the A-type mouse L1 element, we cloned several different A-monomers into a promoterless chloramphenicol acetyltransferase (CAT) vector. The A-monomer constructs varied in their ability to regulate transcription of the CAT gene, exhibiting CAT activity 16-37% of that detected with the Rous sarcoma virus promoter and enhancer. A series of A-monomer deletions were tested for their ability to regulate CAT expression and gel retardation experiments were performed to identify regions of the A-monomer that may be involved in L1 transcriptional regulation. A-monomer sequences are usually found repeated 2-5 times at the 5' end of a full-length mouse L1. In the absence of long terminal repeats or an internal promoter, the tandem array of A-monomers may provide a mechanism for A-type L1 elements to generate transcripts containing transcriptional regulatory sequences.


High prevalence of antibody to hepatitis C virus in heavy drinkers with chronic liver diseases in Japan. To investigate the prevalence of antibody to hepatitis C virus (anti-HCV) in heavy drinkers with liver disease in Japan, we tested serum samples from 113 heavy drinkers with liver disease and 121 without liver disease. All were negative for HBsAg with no history of blood transfusion. These subjects had consumed more than 80 g of ethanol daily for 5 years or more. Findings for anti-HCV determined by recombinant immunoblot assay testing were positive in 14 (35.9%) of the 39 patients with liver cirrhosis, 14 (58.3%) of the 24 patients with hepatocellular carcinoma and in 8 (53.3%) of the 15 patients with chronic hepatitis. The anti-HCV positive rate in the drinkers with these liver diseases was significantly higher than in those with such disorders as fatty liver (0/10), hepatic fibrosis (0/22), and alcoholic hepatitis (0/3), as well as in the alcoholics without liver disease (5/121, 4.2%). Considering histologic findings in the anti-HCV positive cirrhotics, the occurrence of lymph follicle formation (71.4%), piecemeal necrosis (78.6%) and loose fibrosis (64.3%) were observed to a significantly higher extent than in cirrhotics who were negative for anti-HCV. These findings suggest that advanced chronic liver disease among heavy drinkers in Japan, especially of hepatocellular carcinoma, is closely associated with HCV infection. In the livers of heavy drinkers who were positive for anti-HCV, histologic findings indicated the possibility of viral infection.


Characterization of the endogenous nonecotropic murine leukemia viruses of NZB/B1NJ and SM/J inbred strains. We characterized 84 endogenous nonecotropic proviruses of NZB/B1NJ and SM/J inbred strains by examining proviral junction fragment segregation in recombinant inbred (RI) and backcross mice. Forty-five proviruses were shared with other laboratory strains, but 28 were unique to NZB/B1NJ or SM/J. Proviral loci were located on 17 of the 19 mouse autosomes and on both sex chromosomes. These markers will facilitate gene mapping in the NXSM RI set and contribute to the pursuit of a more complete map of the mouse genome.


Development of hepatocellular carcinoma in a man with auto-immune chronic active hepatitis. A 57 year old man with auto-immune chronic active hepatitis, regularly treated with immunosuppressive therapy, had hepatocellular carcinoma (HCC) 10 years after diagnosis of the hepatitis. Assays of the hepatitis C virus antibodies against capsid and non-structural proteins revealed seronegativity in serial serum samples of this patient stored in the previous 10 years during follow up. The seronegative hepatitis C antibodies excluded hepatitis C virus as the cause of the HCC. The occurrence of HCC in this case suggests the necessity of surveillance for early detection of liver cancer in patients with auto-immune chronic active hepatitis undergoing long-term immunosuppressive therapy.


Correlates of human immunodeficiency virus infection in intravenous drug users: are treatment-program samples misleading? Using a community-based sample of 1632 intravenous drug users in Baltimore, Maryland, USA, this study evaluated a possible selection bias faced when studying risk factors for human immunodeficiency virus, type 1 (HIV-1) in intravenous drug users drawn solely from treatment programs. Consenting subjects, recruited by extensive distribution of brochures and word-of-mouth, underwent confidential interviews about drug use behaviors in a setting that was independent of community service agencies. Of 1632 subjects, 275 (17%) were currently enrolled in treatment programs. These subjects were similar in many respects to those not currently in treatment, including HIV-1 seroprevalence; however, they differed in that those not in treatment were more likely to be male, younger and black than those currently in treatment, and to have started injecting drugs more recently. However, associations between HIV-1 seropositivity and a series of demographic and drug-using characteristics were mostly similar in direction and magnitude among subjects currently in treatment and those not in treatment. These results suggest that one-time samples of drug users enrolled in treatment programs do not necessarily present a misleading picture of correlates of HIV-1 seropositivity.


Assessment and management of opioid withdrawal symptoms in buprenorphine-dependent subjects. The spontaneous physical dependence of buprenorphine was assessed in opioid addicts who switched from heroin to sublingual or intravenous buprenorphine. Twenty-two patients were randomly assigned to double-blind administration of methadone (n = 11) or placebo (n = 11) for 13 days after abrupt withdrawal of buprenorphine. Methadone was administered according to four pre-established dosing schedules depending on the previous amount of daily consumed buprenorphine. No methadone-treated patient required modification of the therapeutic regimen, whereas eight of eleven placebo-treated patients needed treatment with methadone. Buprenorphine withdrawal syndrome was of opioid type, began somewhat more slowly, and showed a peak until day 5. The occurrence, time-course and characteristics of buprenorphine withdrawal syndrome make it necessary to reconsider the abuse potential of this analgesic.


Carcinosarcoma of the submandibular salivary gland. Immunohistochemical findings. Carcinosarcomas of the salivary glands are rare lesions that generally have been associated with benign mixed tumors. The authors report a case of a submandibular gland lesion, which occurred in a 64-year-old man, that was composed of intermingled ductal type adenocarcinoma and osteogenic sarcoma with a large component of osteoclast-like giant cells. The local recurrence of the tumor was entirely sarcomatous with no epithelial component observed. There was no histologic evidence of a preexisting or coexisting pleomorphic adenoma. Immunohistochemical studies confirmed two separate populations of tumor cells, corresponding to the histologic growth pattern. The authors review the literature and discuss histogenetic implications of distinction between de novo carcinosarcoma and carcinosarcoma in association with pleomorphic adenoma.


Cereal fiber, calcium, and colorectal cancer. Food intake during the preceding 15 years was evaluated in detail in 41 patients treated for colorectal cancer and an equal number of matched control subjects by means of a dietary history technique that permitted quantitation of nutrients. Dietary habits of the control group could be compared against two larger groups of 371 hospital control and 430 population control subjects. Patients with cancer, who were interviewed after complete recovery from surgery, consumed more fat, protein, and carbohydrates, and thus more energy, than control subjects although these differences were not statistically significant. Per unit energy, the habitual diet of patients with cancer contained less cereal fiber (P less than 0.001), less riboflavin (P less than 0.05), less calcium (P less than 0.05), and less phosphorus (P less than 0.05) than the diet of the control subjects. A high intake of either cereal fiber, total fiber, calcium, and phosphorus in relation to energy intake was found to be associated with a reduced risk ratio of colorectal cancer. For colon cancer separately, a high intake of calcium and cereal fiber was associated with a reduced risk ratio. For rectal cancer, a high intake of total fiber and cereal fiber was associated with a reduced risk ratio. High alcohol consumption correlated with an increased risk ratio. These data are compatible with previous Scandinavian studies relating food consumption to the incidence and mortality of colorectal cancer.


The role of hepatitis B and C viruses in hepatocellular carcinoma in a hepatitis B endemic area. A case-control study. To investigate the role of hepatitis B (HBV) and C viruses (HCV) in hepatocellular carcinoma (HCC) in an HBV endemic area and elucidate the interaction of these two viruses, a case-control study of 128 patients with HCC and 384 age-matched and sex-matched control subjects was done. The positive rates of hepatitis B surface antigen (HBsAg, 77.3%, 99 of 128) and anti-HCV (19.5%, 25 of 128) in patients with HCC were significantly higher than in control subjects (P less than 0.001). Both HBsAg and anti-HCV were important risk factors for HCC (relative risks, 13.96 and 27.12, respectively), and the risk for HCC was elevated significantly to 40.05 (95% confidence interval, 12.57 to 127.6) when HBsAg and anti-HCV were considered simultaneously. These results suggested that HBV and HCV were associated highly with HCC in an HBV endemic area and that these two viruses might contribute independent but synergistic effects to the pathogenesis of HCC.


Radioimmunodetection and autoradiographic localization of monoclonal antibody against human hepatocellular carcinoma in xenografts. The monoclonal antibody against human hepatocellular carcinoma, HAb23, was conjugated with radioiodine and injected into nude mice with human hepatoma xenografts. After 4 to 5 days, the nude mice were scanned by emission computerized topography. The results showed that the xenografts were distinguished clearly. The tumor-liver and tumor-blood ratios were 1.94 to 3.66 and 0.56 to 1.65, respectively. Autoradiography showed that the HAb23 was localized mainly on the surface membrane and tubulovesicular systems of the tumor cells.


Establishment and characterization of a panel of human lung cancer cell lines. The establishment and characterization of 11 human lung cancer cell lines are described in this article. Nine of these cell lines were established over a 5-year period, from 1983 to 1988, from patients treated at the Kingston Regional Cancer Centre. These include eight definite or probable small cell lung cancer (SCLC) lines and one adenocarcinoma line. In addition, two other SCLC cell lines were characterized. All of the lines have been in continuous culture for more than 2 years. The clinical histories of the patients from whom the cell lines were derived are outlined here. Several features of the cell lines are presented, including the following: (1) a comparison of the histologic features of the cell lines with the original biopsy specimens; (2) the expression of various markers, including cytokeratin, carcinoembryonic antigen, calcitonin, and neuron-specific enolase; (3) activities of the enzymes l-dopa decarboxylase and the brain isoenzyme of creatine kinase; (4) growth characteristics; (5) cloning efficiency in soft agar; (6) tumorigenicity in nude mice; and (7) cytogenetic studies. These cell lines, obtained directly from patients with a spectrum of drug-sensitive and drug-resistant tumors, will be valuable in vitro models of sensitivity and resistance to chemotherapy in lung cancer.


Small cell carcinoma of the lung. Treatment in the community. The results of nonprotocol treatment of 232 patients with small cell lung cancer seen by a group of community-based medical oncologists over a 13-year period were evaluated. Factors associated with improved survival also were assessed. The following patient characteristics significantly improved survival: limited stage of disease at diagnosis, treatment of extensive (but not limited) disease with regimens including etoposide and cisplatin, tumor resection, age younger than 70 years, radiation therapy to the chest, and female sex (extensive disease only). Comparison of the data from this study with published results of protocol studies showed similar outcomes.


Expression and growth-promoting effect of adult T-cell leukemia-derived factor. A human thioredoxin homologue in hepatocellular carcinoma. Adult T-cell leukemia-derived factor (ADF), originally defined as an interleukin-2 receptor inducer, is a human thioredoxin homologue. ADF is detected in many malignant tissues and has a growth-promoting effect on transformed cells. In this study, ADF expression was examined immunohistochemically in human liver cell lines and liver tissues, and its growth-promoting effect was tested on human hepatoma cells. On three liver cell line--PLC/PRF/5, HepG2, and Chang liver cells--ADF stained positively and also was detected by immunoblotting. ADF had strong staining in the fetal liver (n = 8), although it was faint in the normal adult liver (n = 6). In hepatocellular carcinoma (n = 25), ADF expression generally was enhanced and was very strong in 52% (13 of 25) of the cases, although it was moderate in cases of chronic hepatitis or cirrhosis. ADF augmented the growth of PLC/PRF/5 cells and showed an additive effect with epidermal growth factor. These results indicate possible involvement of ADF in cell activation and growth of hepatocytes, as is the case with lymphocytes.


Prognostic factors in 227 patients with malignant fibrous histiocytoma. Malignant fibrous histiocytoma, the major subset of soft tissue sarcomas, was examined for prognostic factors that could influence clinical management and research. Two hundred twenty-seven patients with localized disease, having surgery as the principal modality, were reviewed retrospectively to identify clinical outcomes. The mean age of the patients was 54 years. Extremities were the primary tumor site in 157 patients (62.2%). Overall survival rate was 50%, including 38 patients who died of other causes. Distant metastases were most common to the lung (90%). Local recurrence alone occurred in 37 patients (16%), distant metastases alone in 52 (23%), and distant metastases with local recurrence in 25 (11%). The primary tumor size indicated the 5-year survival rate: tumors smaller than 5 cm had a survival rate of 82%; 5 to 10 cm, 68%; and larger than 10 cm, 51%. Intermediate-grade tumors yielded a 5-year survival rate of 80%, and the 5-year survival rate for high-grade tumors was 60%. Survival rates for both grades were affected by size: tumors of high grade and smaller than 5 cm in diameter had a survival rate of 79%; 5 to 10 cm, 63%; and more than 10 cm, 41%. Grade and size emerge as significant prognostic indicators. These variables will prove helpful in treatment decisions and design of clinical studies.


Ovarian mucinous tumors frequently express markers of gastric, intestinal, and pancreatobiliary epithelial cells. In 100 mucinous tumors of the ovary (37 benign, 24 borderline, and 39 malignant), the authors determined by histochemical and immunohistochemical techniques the frequencies and patterns of expression of a total of nine markers of gastric, intestinal, and pancreatobiliary duct epithelial cells. M1, a mucin antigen, and cathepsin E (CaE), an aspartic proteinase, two markers of normal gastric superficial/foveolar epithelial cells, were expressed in 95 and 92 tumors, respectively. Periodic acid-concanavalin A-reactive mucin or pepsinogen (PG) II, markers of gastric mucus neck and pyloric gland cells, were found in 79 tumors. All of these tumors also expressed M1 or CaE. DU-PAN-2 and the N-terminal epitope of gastrin-releasing peptide, markers of normal pancreatobiliary duct cells, were found in 70 and 49 tumors, respectively, and CAR-5 and M3SI, markers of intestinal mucin, were expressed in 51 and 30 tumors, respectively. All tumors expressed at least two of the nine markers studied; none expressed PG I, a marker of gastric chief cells. The mucopeptic cell marker, PG II, was significantly more common in benign and borderline than in malignant tumors (P less than 0.005), whereas CAR-5 and M3SI, markers of intestinal mucin, were expressed significantly more often in malignant than in benign and borderline tumors (P less than 0.001). By electron microscopic examination, many tumor cells had fine structural features characteristic of gastric superficial/foveolar and pyloric gland cells, intestinal columnar or goblet cells, and endocervical cells. The results indicate that gastroenteropancreatic cell differentiation--and, in particular, gastric type differentiation--is a prominent feature of ovarian mucinous tumors.


Extraneural metastases of infratentorial glioblastoma multiforme to the peritoneal cavity. This report describes two autopsy-proven cases of a rare complication of infratentorial glioblastoma multiforme (GBM): metastatic seeding of the peritoneal cavity through ventriculoperitoneal (VP) shunts. Patient 1 was a 13-year-old boy with a pontine GBM, and Patient 2 was a 9-year-old girl with a thoracolumbar spinal cord GBM. Autopsy of both patients demonstrated leptomeningeal gliomatosis encasing the spinal cord and basal structures of the brain, in addition to peritoneal and omental metastases. The pattern of abdominal metastasis seen in these patients is typical of tumors that directly seed the peritoneal cavity and implicates the VP shunt as the vehicle of extraneural spread. Although a rare occurrence, extraneural metastases should be sought in patients with glioma with VP shunts who demonstrate increased abdominal girth, unexplained weight gain, or persistent abdominal pain.


An immunohistochemical study of perianal Paget's disease. Possible origins and clinical implications. The histogenesis of perianal Paget's disease is controversial. A clinical and pathologic study was done of a patient with a history of adenocarcinoma of the rectum for whom a subsequent diagnosis of perianal Paget's disease was the sole manifestation of recurrent rectal cancer. Immunohistochemical techniques were used to compare and contrast the original rectal adenocarcinoma with the subsequent perianal skin recurrence confined to the epidermis. Both the rectal adenocarcinoma and the Paget's cells were positive for cytokeratin, epithelial membrane antigen, B72.3, and carcinoembryonic antigen and negative for gross cystic disease fluid protein-15, Leu-M1, CA 125, and S-100 protein. These findings, their relevance to the histogenesis of perianal Paget's disease, and the possible clinical implications are discussed.


The lessons of life: keynote address to the nutrition and cancer conference. Some 15 years ago there began to emerge a consensus among epidemiologists that diet might be responsible for 30-60% of cancers in the developed world, in the sense that it should be possible to reduce age-specific incidence rates by this amount by practicable dietary change. Within about 6 years it was also broadly agreed that the principal changes required to bring about this effect were a reduction in the consumption of fat; an increase in the consumption of fruit, green and yellow vegetables, dietary fiber, and some micronutrients; and possibly an improvement in the methods of food preservation. Very small effects, if any, were attributed to food additives and to the pollution of food by trace pesticides, which the public, who accepted much of the consensus advice, have increasingly regarded as important causes of risk. These past conclusions are reviewed in the light of increased knowledge of the etiology of cancer and the trends in its incidence. Contrary to common belief, the trends are broadly encouraging.


Dietary fiber-mediated mechanisms in carcinogenesis. Dietary fiber may affect the development of cancers of the gastrointestinal tract and the breast. The biological intermediates studied most have been fecal bile acids; both human and animal studies suggest a tumor-promoting role of bile acids in the development of colon tumors, although there are conflicting data from human studies. Short-chain fatty acids are major fermentation products of bacterial degradation of dietary fiber. If short-chain fatty acids explained the tumor-inhibiting properties of dietary fiber, the readily fermentable fibers such as guar and pectin would be more protective than cellulose and wheat bran, which has not been observed. Because these two hypotheses do not adequately explain modulation of tumor growth by dietary fiber, investigation of other intermediates is indicated. These include physical characteristics of the feces, such as abrasiveness; intestinal microflora; aqueous-phase bile acids, which may represent the bioavailable pool; alterations in mucins; mutagenicity of intestinal contents; alterations in mucosal cytokinetics; activities of enzymes, such as ornithine decarboxylase or aryl hydrocarbon hydroxylase; neurogenic effects caused by changes in intestinal bulk or short-chain fatty acids; gut hormones or other peptide growth factors (local or systemic); enterohepatic circulation of hormones; transit time; pH; or decreased availability of total dietary energy.


Aflatoxins as risk factors for hepatocellular carcinoma in humans. On a global basis, primary liver cancer (PLC) is a very prevalent form of cancer. Wide variation of PLC incidence in different areas of the world suggests the involvement of environmental factors in its etiology. Two major classes of risk factors have been identified. Extensive evidence indicates the importance of infection by the hepatitis B virus as a major risk factor for PLC. Because many organic chemicals induce liver cancer in experimental animals, those to which human exposure is known to occur are also of interest with respect to their possible involvement as risk factors for PLC. Particular emphasis has been placed on aflatoxins because of the frequency with which they occur as food contaminants, together with their potency as liver carcinogens for a large number of experimental animals, including subhuman primates. Other mycotoxins, notably sterigmatocystin and fumonisin, also are relatively potent carcinogens for the liver of animals, but little is known about human exposure to them. Epidemiological surveys carried out over the past 25 years in Asia and Africa have revealed a strong statistical association between aflatoxin ingestion and PLC incidence. The combined experimental and epidemiological evidence has led to designation of aflatoxins as human carcinogens according to International Agency for Cancer Research criteria. Collectively, current evidence strongly suggests that PLC is of multifactorial origin, with probable interactions between viral and chemical agents in populations concurrently exposed to both classes of risk factors. Recently developed methods that permit individual monitoring of aflatoxin exposure, hepatitis B virus infection, and genetic damage caused by these agents are being applied in the design of molecular and biochemical epidemiological studies of the etiology of the disease. Application of this methodology may contribute to elucidation of the relative importance of interacting etiological agents in different populations.


Modulation of monocytic differentiation of HL-60 cells by inhibitors of protein tyrosine kinases. We showed previously that the expressions of various src family protein tyrosine kinases (PTKs) were induced independently during the monocytic differentiation of HL-60 cells. The role of PTKs was further assessed in the present study by investigating the effects of PTK inhibitors on the differentiation. It was demonstrated that PTK inhibitors such as genistein and herbimycin A modulated monocytic differentiation of HL-60 cells; they inhibited the differentiation induced by TPA, while promoting that induced by vitamin D3 (D3). Immunoblotting analysis of protein molecules which had been phosphorylated on their tyrosine residues demonstrated that TPA induced phosphorylation of certain molecules different from those induced by D3 in HL-60 cells. PTK inhibitors blocked the phosphorylation and modulated differentiation driven by the inducers. These data suggest that PTKs are involved both promotively and suppressively in signaling events that induce monocytic differentiation of HL-60 cells.


Autosomal recessive blepharophimosis, ptosis, V-esotropia, syndactyly and short stature. A recessively inherited syndrome of blepharophimosis and ptosis with weakness of extraocular and frontal muscles is reported in six members of three related kindreds. Prognathism, synophrys and thick eyebrows added to a typical facial appearance. Additional findings included short stature, borderline head circumference and toe syndactyly. Borderline mental retardation and anosmia were found in one patient. The clinical features and the mode of inheritance distinguish this syndrome from other blepharophimosis and ptosis syndromes.


Antibodies to hepatitis C virus in essential mixed cryoglobulinaemia. Although essential mixed cryoglobulinaemia (EMC) is recognized to be frequently associated with chronic liver disease, aetiology and pathogenesis of liver damage remain unsolved questions. The purpose of this study was to assess the possible causative role of hepatitis C virus (HCV) in the liver impairment occurring in patients with EMC. Twenty-six consecutive EMC patients were evaluated. All patients underwent percutaneous liver biopsy. Anti-HCV antibodies were assayed by ELISA and supported by a recombinant immunoblotting assay (4-RIBA). The prevalence of anti-HCV antibodies in patients with and without chronic active liver disease (CALD) was compared. Anti-HCV antibodies were detected in 13 patients (50%) by ELISA and confirmed in 11 of them (42.3%) by 4-RIBA, the remaining two patients being indeterminate in the supportive assay. CALD correlated significantly with anti-HCV antibodies: indeed, 7/11 (63.6%) anti-HCV+ patients showed histological and clinical pictures of CALD, compared with 1/15 (6.6%) anti-HCV- patients (P less than 0.01). With the exception of the patient who was found to be HBsAg+, no liver tissue expressed hepatitis B virus-related antigens in the hepatocytes. Additional histological findings included discrete lymphoid aggregates in portal tracts, siderosis, fatty changes, hyperplasia of Kupffer cells. It can be concluded that chronic liver damage in EMC is frequently associated with anti-HCV antibodies. Although the cause of EMC remains unknown, this study has obvious implications for clarifying the etiology of associated CALD and further supports the therapeutic use of interferons in this disease.


Epstein-Barr virus and HIV play no direct role in persistent generalized lymphadenopathy syndrome. Persistent generalized lymphadenopathy (PGL) and polyclonal B cell activation are features of infection with HIV. Epstein-Barr virus (EBV) and HIV are known to activate B cells in vitro, but whether they are important B cell activators in patients infected with HIV is less clear. In this study, lymph node tissue was obtained from 10 patients with PGL and assessed for evidence of EBV and HIV gene sequences. DNA was extracted and specific viral gene sequences identified using the polymerase chain reaction (PCR). EBV sequences were difficult to detect in the PGL tissue, with a signal intensity similar to that of other benign and malignant lymphoid conditions not associated with EBV. HIV sequences were also rare in the PGL tissue, consistent with HIV infection of the small number of peripheral blood cells and nodal T cells likely to be present in such a sample. These findings suggest that the polyclonal B cell activation typical of HIV is not driven by direct EBV or HIV infection of B cells.


Up-regulation of tumour necrosis factor-alpha receptors on monocytes by desferrioxamine. The effect of endogenously generated reactive oxygen metabolites on the interaction of human blood monocytes with tumour necrosis factor-alpha (TNF-alpha) was investigated. Pre-exposure of unactivated human blood monocytes to dimethylthiourea, a scavenger of hydroxyl radical (OH.), or to desferrioxamine (DFX), an iron chelator preventing the synthesis of OH., enhanced the specific binding of 125I-TNF-alpha to its receptors. Scavengers of superoxide anion or hydrogen peroxide were without effect. DFX-induced up-regulation of 125I-TNF-alpha binding depended on the concentration of the drug (1-5 mM) and on the duration of the treatment (1-18 h). It was not due to a reduction of receptor occupancy by endogenously generated TNF-alpha. Scatchard analysis of binding data revealed that DFX caused an approximately two-fold increase in the number of type II TNF-alpha receptors, with no change in their affinity. This up-regulation, that did not require synthesis of new proteins, was associated with a decrease in the internalization rate of TNF-alpha receptors, the half-life of which was doubled. Conversely, these findings suggest that OH. generation by monocytes may have a physiological role in reducing the activity of membrane-associated TNF-alpha receptors.


Vasoactive intestinal peptide stimulates immunoglobulin production and growth of human B cells. The effect of vasoactive intestinal peptide (VIP) on human lymphoblastoid B cell lines and tonsil B cells was studied. VIP increased immunoglobulin production and proliferation by lymphoblastoid B cell line, GM-1056, in a dose-dependent manner. As little as 10(-12) M of VIP was effective, and higher concentrations of VIP induced an approximately five-fold increase in IgA production. Moreover, this enhancement was blocked by VIP antagonist. Similarly, VIP enhanced IgM and IgG production by other lymphoblastoid B cell lines, CBL and IM-9, respectively. In contrast to VIP, another neuropeptide substance P (SP) or somatostatin failed to enhance immunoglobulin production and thymidine uptake. VIP also enhanced IgA production and thymidine uptake by purified tonsil B cells. However, in contrast to B cell lines, VIP failed to enhance IgM and IgG production by tonsil B cells. SP or somatostatin failed to enhance immunoglobulin production or thymidine uptake by tonsil B cells. These results indicate that VIP acts as B cell stimulatory factor and that VIP may also have preferential effect on IgA production on tonsil B cells.


Parathyroid carcinoma. Report of three cases. Primary or relapsing hyperparathyroidism should not be considered a result only of benign conditions like adenoma or hyperplasia (primary or secondary). Parathyroid carcinoma is often the real cause but, because of its rarity, sometimes it is either overlooked or misdiagnosed. Even histologic classification can be erroneous. Distant metastases or ectopic location of the tumors are another potential cause of misdiagnosis, especially when management is decided without the help of diagnostic imaging modalities, particularly those related to the functional aspect of the tumors or their metastases, such as the Tl-201/Tc-99m subtraction scan and the Tl-201 whole body scan.


Simple procedure for red blood cell labeling with Tc-99m HMPAO. Preliminary clinical results. Clinical applications for Tc-99m HMPAO labeled red blood cells have not been previously reported. The authors describe a simple, aseptic, closed, one-step centrifugal procedure for red blood cell labeling with Tc-99m HMPAO and isolation from whole blood, and they report the preliminary results of using these labeled red blood cells to detect acute gastrointestinal bleeding in 11 patients. Whole blood was radiolabeled with Tc-99m HMPAO preparation and blood cells were separated by centrifugation (30 min, 200 g, 20 degrees C) using Polyprep density gradient medium. Red blood cells contained about 50% of the radioactivity. Four out of the 11 patients imaged with a gamma camera after reinjection of labeled autologous red blood cells showed abnormal accumulation, suggesting gastrointestinal bleeding that was verified at surgery and was at the site of abnormal activity in all cases. Image quality with Tc-99m HMPAO was comparable to that of Tc-99m pertechnetate labeled pretinned red blood cells. Tc-99m HMPAO can be used as a red blood cell labeler; however, its elution rate from red blood cells limits its applicability in some investigations.


Dose responses and pharmacokinetics for the angiotensin converting enzyme inhibitor quinapril. Single doses of the angiotensin converting enzyme (ACE) inhibitor quinapril were administered to salt replete normotensive men to investigate pharmacokinetics and dose responses. Maximal ACE inhibition was produced by the 2.5, 5, and 20 mg doses (but not by 0.5 mg), but there was evidence of dose-dependency only for the duration of ACE inhibition. Quinaprilat was detectable in plasma up to 72 hours after all doses and the terminal phase half-life was calculated at 26 +/- 7 hours. Although there were dose-related increases in area under the curve (AUC), the relationships between dose and both AUC and maximum concentration were nonlinear. These findings suggest that quinapril displays the same prolonged terminal phase half-life that is characteristic of other ACE inhibitor drugs. The failure of doses above 2.5 mg to produce any further increase in the magnitude of ACE inhibition is consistent with an maximum effect dose-response relationship, with the obvious implication that higher doses will increase only the duration not the magnitude of response.


Differential response of beta-adrenergic receptor-mediated heart rate and aortic blood flow acceleration to timolol. The apparent affinity of beta-adrenergic receptors for timolol in the sinus node and ventricular myocardium was compared in 11 normal male subjects. Sinus nodal function was assessed by heart rate, and left ventricular systolic function was assessed by Doppler-derived aortic blood flow acceleration. The dose of isoproterenol required for a heart rate or acceleration increase of 35% (I35) was determined before and 2 hours after an oral 10 mg dose of timolol. The apparent affinity constant (ka) for timolol binding to the receptor was calculated from the serum timolol concentration and the ratio of the I35 after timolol/I35 before timolol. The I35 for sinus node and ventricular myocardium were not significantly different from one another. The ka for timolol binding to the sinus node (1.14 x 10(6) mol/L), however, was significantly greater (p less than 0.05) than ka for ventricular myocardium (7.85 x 10(5) mol/L). These findings suggest that beta-adrenergic receptors in the sinus node may have an overall greater affinity for beta-blocking agents than do receptors in the ventricular myocardium.


Long-term ergotamine abuse: effect on adrenergically induced mydriasis. The mydriatic action of sympathomimetic eyedrops after a therapeutic dose of ergotamine was measured in migraine patients with and without histories of long-term ergotamine abuse. Mydriasis induced by the postsynaptic alpha 1-agonist phenylephrine was similar in both groups of patients tested, whereas pupillary dilation caused by the release of noradrenaline tyramine was markedly greater in patients with histories of ergotamine abuse. The enhanced response to tyramine disappeared after drug withdrawal. These findings indicate that continuous ergotamine medication causes a reversible alterations in iris sympathetic transmission. This manifestation may reflect a central inhibition of pupillary sympathetic activity.