Epidermis generated in vitro: practical considerations and applications

The technology for culture of epidermis is one of the most advanced to date for generation of a tissue in vitro. Cultured epidermis is already used for a number of applications ranging from use as a permanent skin replacement to use as an organotypic culture model for toxicity testing and basic research. While simple epidermal sheets have been grafted successfully, more advanced models for skin replacement consisting of both dermal and epidermal components are in development and being tested in a number of laboratories. One of the most advanced in vitro models is the living skin equivalent, an organotypic model consisting of a collagen lattice contracted and nourished by dermal fibroblasts overlaid with a fully formed epidermis.

Fimbrin is a homologue of the cytoplasmic phosphoprotein plastin and has domains homologous with calmodulin and actin gelation proteins

Fimbrin is an actin-bundling protein found in intestinal microvilli, hair cell stereocilia, and fibroblast filopodia. The complete protein sequence (630 residues) of chicken intestine fimbrin has been determined from two full-length cDNA clones. The sequence encodes a small amino-terminal domain (115 residues) that is homologous with two calcium-binding sites of calmodulin and a large carboxy-terminal domain (500 residues) consisting of a fourfold-repeated 125-residue sequence. This repeat is homologous with the actin-binding domain of alpha-actinin and the amino-terminal domains of dystrophin, actin-gelation protein, and beta-spectrin. The presence of this duplicated domain in fimbrin links actin bundling proteins and gelation proteins into a common family of actin cross-linking proteins. Fimbrin is also homologous in sequence with human L-plastin and T-plastin. L-plastin is found in only normal or transformed leukocytes where it becomes phosphorylated in response to IL 1 or phorbol myristate acetate. T-plastin is found in cells of solid tissues where it does not become phosphorylated. Neoplastic cells derived from solid tissues express both isoforms. The differences in expression, sequence, and phosphorylation suggest possible functional differences between fimbrin isoforms.

A study on the effects of estradiol and estramustine on gastrointestinal cell lines

We have studied the effect of estradiol and the combined estradiol/nitrogen mustard compound estramustine on cell lines derived from human gastric and colorectal cancers. Significant stimulation of the two gastric and two fo the colorectal cell lines occurred at physiological concentrations of estradiol. Estramustine showed an inhibitory effect in all of the cell lines at 10 micrograms/l, and a direct dose-dependent inhibition was seen in two of the cell lines. Each of the cell lines was immunohistologically stained using the estrogen-receptor-related protein ERD5, and all of the cell lines except one were positive for this protein. The inhibitory effect of estramustine was lost with increasing concentrations of estradiol, suggesting that the effects of estramustine may be linked to estrogen receptors. We conclude that reduction of circulating levels of estradiol, or treatment with estramustine may have a beneficial effect in the palliation of gastrointestinal malignancy.

Cytotoxicity of Mycoplasma mycoides subspecies mycoides for cultured endothelial cells

Toxic effect of 5 SC- and 4 LC-type strains of Mycoplasma mycoides subspecies mycoides has been demonstrated in cultured endothelial cells. The SC strains are agents of contagious bovine pleuropneumonia and presumably specific for cattle although occasionally isolated from goats. The LC strains produce an acute septicemic disease in goats and a few strains have been reported in cattle. The tissue culture cytotoxic dose causing 75% cell death (TCCD75) was calculated for each strain. Cytotoxicity ranged from 0.9 X 10(9) to 12.0 X 10(9) when strains were tested in bovine endothelial cells with the SC strains being twice as cytotoxic as the LC strains on average. Strains G175/78 and D44 representing the most cytotoxic SC and LC strains respectively, were selected for comparative experiments using bovine, caprine and porcine endothelial cells, bovine embryonic lung fibroblast cells (BELF) and the bovine cell line Madin-Darby kidney cells (MDBK). Strain G175/78 was significantly more cytotoxic for bovine endothelial cells than caprine and porcine, suggesting that the cytotoxicity reflects specificity for the bovine species. This strain was also cytotoxic for BELF but not for MDBK cells indicating that not all bovine cells are susceptible. Conversely, cytotoxicity of strain D44 was not significantly different in any of the endothelial cells tested, although cytotoxicity for BELF was significantly different, the cytotoxicity of the LC strains seems to be of less specificity.

The effect of sex hormones and tamoxifen on the growth of human gastric and colorectal cancer cell lines

The authors studied the effect of serial concentrations of estradiol, 4-hydroxytamoxifen with estradiol, and 5-dihydrotestosterone on cell lines derived from human gastric and colorectal cancers. Significant stimulation of the gastric and 2 colorectal cell lines occurred at physiologic concentrations of estradiol. Addition of the active metabolite of the estrogen-receptor blocker/partial-agonist 4-hydroxytamoxifen had a stimulating effect on the growth rate of the gastric cell lines. The androgen, 5-dihydrotestosterone, had a modest inhibitory effect on the two gastric cell lines and two of the colorectal cell lines, and a stimulating effect on two further cell lines.

Gastrin: growth enhancing effects on human gastric and colonic tumour cells

Two colorectal (HT29, LoVo) and one gastric (MKN45) human tumour cell lines were examined for their in vitro trophic response to human gastrin-17. MKN45 and HT29 responded by increased 75Se selenomethionine uptake to exogenous gastrin (139 +/- 5.5% and 123 +/- 3% of control values respectively) whereas LoVo showed no significant response to this hormone. When these same cell lines were grown as xenografts in nude mice, similar responses were seen to exogenously administered human gastrin-17 (10 micrograms mouse-1 day-1, subcutaneous injection). MKN45 xenografts showed a greater response to continuously administered gastrin (osmotic mini-pumps, (10 micrograms mouse-1 day-1) when compared to the same dose given via a subcutaneous bolus injection. The hormone-treated xenografts had a two-fold increase in tumour cross-sectional area and growth rate when compared to saline-treated controls. Dose-response studies revealed that 0.4 micrograms gastrin mouse-1 day-1 appeared to be the minimally effective dose. As gastric and colorectal tumour cells show a trophic response to gastrin, antagonists of the gastrin receptor may prevent this effect causing tumour stasis. The gastric tumour cell line, MKN45, is gastrin-responsive and would be an ideal model for screening potent receptor antagonists.

Spontaneous pregnancies and pregnancies as a result of treatment on an in vitro fertilization program terminating in ectopic pregnancies or spontaneous abortions

Five hundred three patients were accepted for the in vitro fertilization (IVF) program from 1983 to 1986. Two hundred ninety-nine patients had a total of 678 IVF treatment cycles during this period. Eighty-one clinical pregnancies resulted, of which 8 were ectopic pregnancies and 19 spontaneous abortions (group A). During this period 82 patients accepted for IVF became pregnant spontaneously: 44 before treatment and 38 after a failed IVF treatment cycle (group B). Of these, 14 were ectopic pregnancies and 8 were miscarriages. The main indications for acceptance on the IVF program were similar in the two groups if those patients who had a bilateral salpingectomy are excluded from group A. Causative factors for the high ectopic pregnancy rate are discussed. The authors suggest that after embryo transfer, migration of the embryo or embryos into the fallopian tubes occurs more frequently than realized, and the diseased tube is less likely than a normal tube to propel the embryo back into the uterus. The abortion rate in group B was similar to the rate in the general population.

Evaluation of heat-sensitive, neutrophil-toxic, and hemolytic activity of Haemophilus (Actinobacillus) pleuropneumoniae

Cytotoxic and hemolytic activity of Haemophilus (Actinobacillus) pleuropneumoniae serotype 1 strain CM5 was investigated because of the potential role as a virulence determinant. Viable bacteria were toxic for porcine and bovine neutrophils, whereas bacteria killed by heat treatment at 60 C for 1 hour were not. Similarly, bacteria-free culture supernatant was cytotoxic and hemolytic in assays that used porcine neutrophils and erythrocytes, whereas supernatant treated at 60 C for 1 hour had no activity. Erythrocytes from various species were susceptible to the hemolytic activity of bacteria-free culture supernatant, with ovine and bovine erythrocytes being most sensitive. The neutrophil-toxic and hemolytic activity of bacteria-free culture supernatant was inhibited by cholesterol and oxygen and abolished after trypsin digestion. The neutrophil-toxic and hemolytic activity was preserved during storage at or less than 4 C, but was lost rapidly at 56 C or 80 C. Neutralizing antibodies were demonstrated in serum of pigs and rabbits immunized with 10-fold concentrated culture supernatant of strain CM5 and in field pigs that had recovered from natural infection with H pleuropneumoniae serotype 1. Bacteria-free culture supernatants of 18 strains, including H pleuropneumoniae serotypes 1 through 10, Actinobacillus suis, and Haemophilus taxon minor group, were tested for heat-sensitive, neutrophil-toxic, and hemolytic activity. Fifteen strains were neutrophil toxic, but only 10 of these were hemolytic. Haemophilus pleuropneumoniae, serotype 1, strain VLS557; serotype 5, strain K17; and Haemophilus taxon minor group strain 33PN were neither cytotoxic nor hemolytic.

Donor oocyte pregnancy with transfer of deep-frozen embryo

An infertile woman suffering from premature menopause conceived on her eighth attempt of ET following the transfer of a single frozen-thawed embryo, the ovum being donated anonymously by a patient undergoing tubal sterilization.

Immunohistochemical localization of aminopeptidase M in rat brain and periphery: relationship of enzyme localization and enkephalin metabolism

An antiserum specific for rat aminopeptidase M has been used for the immunohistochemical localization of the enzyme in rat brain and peripheral tissues. The enzyme in brain is localized exclusively on blood vessels. Within the pituitary the enzyme was associated with the vasculature in the posterior lobe, on the surface of the intermediate lobe and on the surface of some cells in the anterior lobe. In the liver, fine cell staining was observed between parenchymal cells, in the ileum the entire lumenal surface was stained, while in the kidney both proximal tubular and a central tubular staining was detected. In each tissue aminopeptidase M is localized such that it can limit diffusion across specific barriers. Aminopeptidase M activity in brain has been proposed to function in the degradation of synaptically released enkephalins. Its localization on blood vessels requires that enkephalins diffuse prior to degradation, a concept not in concert with current hypotheses. Based on these studies it is proposed that diffusion away from enkephalinergic synapses plays a key role in terminating enkephalin action.

Sequential hydroxyurea-cytarabine chemotherapy for refractory non-Hodgkin's lymphoma

In experimental systems, hydroxyurea (HU) and cytarabine (ara-C) produce synergistic cytotoxicity to murine and human leukemia cells due to both cytokinetic and biochemical interactions that tend to enhance the effectiveness of ara-C. Therefore, we began a phase II trial of the combination of HU and ara-C to determine the efficacy and toxicity of this combination in treatment of patients with refractory non-Hodgkin's lymphoma. Chemotherapy began with HU 500 mg administered orally every six hours for four doses. Twelve hours following the fourth HU dose, ara-C 100 mg/m2/d was administered by continuous intravenous (IV) infusion for three days. Concomitantly with the three-day ara-C infusion, patients again received HU 500 mg orally every four hours. Cycles of therapy were repeated every 28 days. Twenty-five patients ranging in age from 26 to 70 years were enrolled in the study. Of 21 patients evaluable for response, nine (43%) obtained complete (CR) or partial remissions (PR). Most responding patients had either large-cell or cutaneous T cell lymphoma, and all but two had a performance status of 0 to 1 at entry in the study. The median survival for all responding patients was 13 months compared with 2.5 months for nonresponders. Patients obtaining a CR had a median survival of 27.5 months, and two of the four CRs remain alive and in remission at 10+ and 30+ months from achievement of CR status. The primary toxic effect of this regimen was bone marrow suppression. The median WBC nadir was 2,200 cells/microL, and the median platelet nadir was 80,000/microL. Other toxicities included mild nausea and vomiting and diffuse maculopapular rash. This biochemically rational approach to enhancing ara-C activity may have significant clinical utility and should be further explored in treatment of patients with large-cell and cutaneous T cell lymphomas.

Infections of the lower extremities due to gas-forming and non-gas-forming organisms

From 1977 to 1984, 87 above- and below-knee amputations were done on 77 patients for ischemic ulcerations and gangrene of the lower extremities. The overall three-month mortality was 14% and was mainly related to generalized atherosclerosis. Patients having infections with gas formations were more likely to be diabetic (80% vs 15%, P less than .01), have clinical sepsis and a higher preoperative WBC (19,000 vs 12,600/cu mm, P less than .01), and have a higher mortality (40% vs 12%, P less than .05) than those with infections due to non-gas-forming organisms. Mixed bacterial flora were cultured from most wounds. We conclude that infections with gas formation may be due to either clostridial or nonclostridial organisms, mortality is higher if gas accumulates and if the patient is diabetic, gas is more likely to accumulate in infected extremities of diabetic patients, and the combination of gas formation and diabetes is highly lethal.

Detection of antibodies to Mycoplasma felis in horses

Mycoplasma felis has been isolated from horses with pleuritis, and limited research indicates that mycoplasma pleuritis can be reproduced in horses. The serodiagnostic potential of the indirect hemagglutination and the metabolism-inhibition tests was evaluated by testing 177 horses for antibodies to M felis. Seven horses with M felis pleuritis developed antibodies, and 6 horses with sterile or bacterial pleuritis had high titers suggesting a previous M felis infection. Six horses with pleuritis (one sterile and five bacterial) had low or no titers to M felis. Only one of 30 horses with conditions other than respiratory diseases seroconverted during hospitalization and the remaining horses had low titers. Seventy-eight foals, 4 to 6 months old, from one farm did not have titers, whereas 7 out of 50 yearlings from the same farm had high titers in the indirect hemagglutination test and titers in the metabolism-inhibition test. It appears that both tests are suitable for serodiagnosis of M felis infection in horses.

Affective disorders in referred children and younger siblings of manic-depressives. Mode of onset and prospective course

We studied 68 referred juvenile offspring or siblings of adult bipolar patients. Mean age at onset of affective and related disturbances was 15.9 years (range, 6 to 24 years). Although four of the ten prepubertal children had hypomanic features, full-blown manic psychosis did not appear before puberty. In the sample at large, 12 were classified as dysthymic and ten as cyclothymic. Eleven additional subjects with polysubstance abuse, who at onset did not meet criteria for affective disorder, were reclassified as having either a dysthymic or a cyclothymic disorder during follow-up. Of the remaining patients--24 depressive, eight manic, and three mixed state--71% experienced recurrences; mood-incongruent features, present in four cases at onset, recurred in only one patient during subsequent episodes. Overall, half the sample evidenced signs of bipolarity during a mean prospective follow-up period of three years.

Indium 111 toxicity in the human lymphocyte

Indium-labeled lymphocytes were examined for response to a variety of mitogens, ability to synthesize immunoglobulins, mitotic index, and presence of chromosome aberrations at a range of exposures from 0.2 to 500 muCi/10(8) cells. Results of all four tests were found to be abnormal when the lymphocytes were labeled with 111In activities well within those employed for diagnostic testing.

Interleukin 1 production by peripheral blood mononuclear cells from leprosy patients

Quantitation of interleukin 1 production by adherent mononuclear cells from peripheral blood was performed in patients with tuberculoid and lepromatous forms of leprosy. Cells from patients with tuberculoid leprosy either secreted interleukin 1 spontaneously or produced amounts within the normal range in response to lipopolysaccharide stimulation. Conversely, stimulated cells from lepromatous patients failed to produce interleukin 1 in 5 of 13 (38.5%) cases.

Rapid turnover transport proteins, plasma albumin, and growth in low birth weight infants

The purpose of this investigation was to establish normative data and to determine the value of measuring rapid plasma turnover proteins in low birth weight infants during the neonatal period. Forty-three premature, adequate for gestational age infants were divided in three groups according to their birth weight: group A less than 1000 g, group B 1001 to 1500 g, group C 1501 to 2000 g. Weekly anthropometric measurements and biochemical determinations were obtained. Anthropometric measurements included weight, crown heel length, midtricipital skinfold thickness, and midarm circumference. Biochemical studies in plasma included total proteins, albumin, prealbumin, and retinol-binding protein. A significant increase in prealbumin concentration preceded weight gain. The elevation in prealbumin concentration was statistically significant (p less than 0.02) for the combined data from all groups and for infants included in group B and C (p less than 0.05). No concomitant changes were demonstrated in plasma retinol-binding protein, or total proteins. The transient rise in prealbumin plasma concentrations remains unexplained, but may be related to the infant's nutritional status.

Treatment of neonatal diabetes insipidus with desmopressin

We report a case of neurogenic diabetes insipidus in a premature infant. It was treated with desmopressin, which appears to be the drug of choice for the treatment of this disease in early infancy.

Analysis for Fusarium toxins in various samples implicated in biological warfare in Southeast Asia

Samples of leaves, water, cereal grains, soil, and yellow powder as well as blood, urine, and body tissues from chemical warfare victims were analyzed for Fusarium toxins by using gas chromatography and mass spectrometry. The leaves, water, and yellow powder samples contained various combinations of T-2 toxin, diacetoxyscirpenol, deoxynivalenol, nivalenol, and zearalenone in concentrations ranging from trace (1.0 ppb) amounts to 143 ppm. These trichothecenes do not occur naturally on the substrates described and were correlated with the so-called "yellow rain" chemical attacks against Hmong people in Southeast Asia. Analysis of leaves, soil, water, and cereals collected in areas adjacent to but apart from the area where chemical attacks had been staged did not contain any Fusarium toxins. Moreover, T-2 and HT-2 toxins were found in human blood, urine, and body tissues (heart, esophagus, kidney, lung, and large intestine) of alleged victims. In addition, diacetoxyscirpenol was found in the kidney of one person who had died.