Cytokine production by cells in cerebrospinal fluid during experimental allergic encephalomyelitis in SJL/J mice

Cytokine production by T cells in the cerebrospinal fluid (CSF) and central nervous system (CNS) of SJL/J mice during myelin basic protein (MBP)-induced experimental allergic encephalomyelitis (EAE) was examined. Reverse transcriptase/polymerase chain reaction (RT/PCR) was used to measure interleukin-2 (IL-2) and interferon-gamma (IFN-gamma) mRNA levels from perfused CNS tissue (brain and spinal cord) and from cells isolated from CSF. Animals were grouped according to EAE severity, ranging from asymptomatic (adjuvant only) to severe disease (paralysis or severe paresis). Cytokine signals, normalized to actin, were almost undetectable in control tissues, and only slightly elevated in whole CNS tissue from animals with mild EAE. Both cytokine messages were strongly upregulated in CNS tissues derived from severely affected animals, consistent with previous observations correlating disease progression with infiltration by memory/effector CD4+ T cells, the major source of these cytokines. This cytokine upregulation was specific to the CNS, since other organs from the same animals did not express significant levels of IL-2 and IFN-gamma. CSF was obtained from the cisterna magna of unperfused mice and verified as such by absence of red blood cells (RBCs) and by immunoglobulin concentration orders of magnitude lower than in serum. Cytokine message was measured in RNA isolated from cells in CSF. Levels of IL-2 and IFN-gamma mRNA in CSF cells were significantly elevated in mild EAE and strongly upregulated in severe disease, correlating with those in total CNS tissue. These results confirm the CSF as representative of the immune status of the CNS and indicate a role for IL-2 and IFN-gamma in inflammatory CNS disease.

Effects of systemic administration of 6-hydroxydopamine, 6-hydroxydopa and 1-methyl-4-phenyl-1,2,3,6-tetrahydroxypyridine (MPTP) on tuberoinfundibular dopaminergic neurons in the rat

Using systemic route of administration, the effects of several neurotoxins on hypothalamic tuberoinfundibular dopaminergic neurons were focused in this study. 6-Hydroxydopamine (6-OHDA, 10 or 100 mg/kg b.wt., i.v. or ip) produced a dose (37 vs. 50%)- and time (41 to 29% from day 4 to day 9)-dependent depletion of hypothalamic median eminence dopamine concentrations, and increases of serum prolactin levels in ovariectomized rats. Other central dopaminergic neurons, however, were not significantly affected. Similar treatments with 6-hydroxydopa (6-OHDOPA) were less effective. On the other hand, treatments of 1-methyl-4-phenyl-1,2,3,6-tetrahydroxypyridine (MPTP, 10 mg/kg b.wt./day, ip) for 7 or 14 days produced significant decreases of dihydroxyphenylacetic acid (DOPAC) levels in the median eminence and periventricular regions, and increases in serum prolactin levels. Other central dopaminergic neurons were not significantly affected, though. These results suggest that systemic administration of 6-OHDA, 6-OHDOPA, or MPTP, can produce specific destructive effects on the tuberoinfundibular dopaminergic neurons.

An international perspective of active euthanasia: attitudes of nurses in seven countries

This exploratory study examines the ethical justification that cancer care and dementia care nurses gave for active voluntary euthanasia. A convenient sample of 319 nurses working in seven countries was interviewed using a structured interview guide. The great majority of the nurses could not ethically justify active voluntary euthanasia. Even if the law changed, only 96 of the total sample viewed active voluntary euthanasia as ethical. For those nurses who could ethically justify active voluntary euthanasia, the majority did so because of the patients' suffering.

Cloning and expression of the gene encoding Acacia confusa trypsin inhibitor that is active without post-translational proteolysis

A recombinant plasmid containing the coding regions for Acacia confusa trypsin inhibitor (ACTI) has been constructed and expressed in Escherichia coli cells, as a fusion protein between ACTI and glutathione S-transferase (GST). The GST-fusion was produced as a soluble protein which did not require denaturing agents such as urea to solubilize it. The recombinant ACTI (reACTI) was obtained by treating the GST-fusion protein with thrombin. Both the reACTI and fusion protein have a strong inhibitory effect on trypsin activity without post-translational proteolysis.

Diagnoses after laparotomy for a mass in the pelvic area in women

The management and outcome of 80 women with an undiagnosed pelvic mass who were referred to the Gynecologic Oncology Division at the University of Rochester during a one year period were reviewed. All patients underwent an exploratory laparotomy for definitive diagnosis. We correlated the final diagnosis with the results of preoperative evaluation and intraoperative assessment. Of the 80 patients, 48 were diagnosed with malignant disease. Of patients with carcinoma, 32 had carcinoma of the ovaries, two had other gynecologic malignancies, ten had nongynecologic malignancies and four had synchronous gynecologic and nongynecologic carcinomas. Carcinoma of the colon and rectum was the most common nongynecologic carcinoma; other malignant diseases were found in the endometrium, vagina, colon and rectum and the breast as well as lymphoma. Preoperative roentgenographic examinations and colonoscopy only had a sensitivity of 38 percent in detecting primary carcinoma of the colon and rectum. Ultrasound of the pelvic region and computed tomographic scan of the abdomen did not improve prediction of malignant disease in the patient population. Serum CA 125 was elevated in 26 of 37 patients with a carcinoma; however, it was elevated with relatively equal frequency in carcinomas of the ovaries and colon and rectum. Intraoperative frozen section accurately identified the primary site of the disease in 90 percent of the patients. However, in the presence of a tumor in the ovaries, carcinomatosis and a tumor in the colon, the results of frozen section were erroneous in four of six patients. Because preoperative assessment seems to be of limited value in excluding nongynecologic lesions, we recommend that pelvic surgeons be prepared to manage operatively a variety of malignant disease or have appropriate consultation available at laparotomy.

Glucose effects in an ovarian cancer protocol of exceptional activity

A French multidrug protocol for stage III ovarian cancer has achieved 77% pathologic complete response, 100% total response, and 81% actuarial 4-year survival. Our analysis indicates that these rates exceed typical with very high statistical significance. Yet neither the drugs, the combined intravenous and intraperitoneal mode of delivery, nor potential bias in the predominantly suboptimal patient population appear to explain the protocol's exceptional results. Here we propose that the atypical administration of intraperitoneal glucose prior to drugs underlies the unusual activity of this protocol. We review studies demonstrating that high-dose glucose has pronounced effects on cancer cells, most notably, substantial potentiation of certain antineoplastic agents. We consider possible mechanisms of such glucose potentiation, including hypothesized osmotic effects that would be especially strong under intraperitoneal administration. We conclude that the French ovarian cancer protocol may represent a significant advance and that glucose potentiation may be more widely applicable as an adjunct to cancer chemotherapy.

Entamoeba histolytica proteins modulate the respiratory burst potential by murine macrophages

Reactive oxygen intermediates are important components of macrophage microbicidal mechanisms and pathogenesis of parasitic disease. The purpose of the present study was to investigate the effect of virulent Entamoeba histolytica (strain HM1-IMSS) on respiratory burst potential of macrophages. Pretreatment of elicited peritoneal macrophages (EPM) with crude soluble amoebic proteins from 1 to 6 hr was found to prime EPM for enhanced O2 and H2O2 release in response to phorbol myristate acetate (PMA) in a dose-dependent manner, whereas pretreatment with the same concentrations of the non-pathogenic E. histolytica-like Laredo strain was without priming effect. Low molecular weight (MW) amoebic proteins (27,000-67,000) purified by Sephacryl-200 column chromatography and subfractionated by diethylaminoethyl cellulose chromatography were 10-fold more potent than crude amoebic proteins in priming EPM for an enhanced respiratory burst potential. Both crude and purified amoebic proteins inhibited the priming effect of lipopolysaccharide (LPS) or interferon-gamma (IFN-gamma) and antagonized the stimulating effect of PMA. Amoebic proteins by themselves were incapable of stimulating EPM respiratory burst. These findings demonstrate that amoebic proteins are capable of modulating the respiratory burst response of macrophages, suggesting an important role for them in the immunoregulation and pathogenesis of amoebiasis.

The complete amino acid sequence of a Kunitz family trypsin inhibitor from seeds of Acacia confusa

The complete amino acid sequence of a Kunitz-type two-chain trypsin inhibitor was determined for the first time. The sequence of the inhibitor from Acacia confusa (ACTI) was determined by analysis of peptides obtained from the reduced and S-carboxymethylated protein by digestion with endopeptidase Lys-C, endopeptidase Arg-C, and V8 endopeptidase. ACTI is comprised of two chains, namely A and B chains linked by the disulfide bridge between Cys(133) and Cys(141), and the inhibitor consists of 175 amino acid residues, 136 residues in the A-chain and 39 residues in the B-chain. The N-terminal amino acid sequence of ACTI shows extensive homology to the trypsin inhibitors from Acacia elata and Albizzia julibrissin, while the whole amino acid sequence of ACTI has a high degree of homology to the other Kunitz-type trypsin inhibitors from soybeans, winged bean seeds [Psophocarpus tetragonolobus (L) DC.], and seeds of Erythrina species.

Primary structure of three distinct isoabrins determined by cDNA sequencing. Conservation and significance

A family of toxic proteins, the isoabrins, which possess N-glycosylase activity toward eukaryotic 28 S r-RNA, may have potential use in cancer chemotherapy. By polymerase chain reaction techniques, cDNA clones of three isoabrins, carrying A and B-chain sequences, were isolated and their nucleotide sequences were determined. The isoabrins consist of an A-chain comprised of 250 of 251 amino acids, followed by a 10 amino acid linker and a B-chain of 267 amino acids. There is substantial conservation in the B-chain of the three isoabrins, with less than six amino acid substitutions, whereas as many as 46 amino acid substitutions occur in the A-chains. Based on the relationships between the biological activities and the putative amino acid sequences of the isoabrins, three isoabrins, abrin-a, -b and -d, could be identified and the potential epitope of immunological response of these isoabrins could be assigned.

Effects of various neuroactive substances on single-unit activities of hypothalamic arcuate neurons in brain slices

Extracellular single-unit activities of 288 dorsomedial/ventrolateral hypothalamic arcuate (ARC) neurons were studied electrophysiologically in brain slices in vitro. We tested the effects of several neuroactive substances plus some of their analogs in this study. Among them, baclofen, a GABAb-receptor agonist, inhibited 95.6% of ARC neurons tested, although GABA itself was much less effective (23.8%). About half of baclofen's effect was blocked by phaclofen, a GABAB antagonist. Serotonin and dopamine also exhibited mostly inhibitory effects on responsive ARC neurons (80 and 78.4%, respectively), although more than half ARC neurons tested (53.3% of 169) were not responsive to dopamine. Neither ketanserin, a 5-HT2, nor domperidone, a D2 receptor antagonist, had much effect on blocking the actions of 5-HT or DA. Histamine and carbachol excited 67.4% and 52.2% of ARC neurons tested, respectively. Moreover, their effects were completely blocked by pyrilamine, a H1, and atropine, a muscarinic receptor antagonist, respectively. Ranitidine, a H2 receptor antagonist, however, was less effective. Norepinephrine had about equal number of excitation (33.3%) and inhibition (38.5%) on ARC neurons. Cholecystokinin-octapeptide sulphate (CCK-8S), a neuropeptide tested exerted potent excitatory effects on ARC neurons (62.8% of 137). In summary, ARC neurons in a more localized region aiming at the tuberoinfundibular dopaminergic neurons were selected in this study. Their responses to many agents and the implications on the regulation of prolactin secretion were discussed.

Bombesin and neurotensin excite neurons in hypothalamic arcuate nucleus in brain slices: an extracellular single-unit study

Using extracellular single-unit recording in brain tissue slices, the effects of bombesin (Bomb), neurotensin (NT), and their analogs on hypothalamic arcuate (ARC) neurons were tested in this study. Adult ovariectomized Sprague-Dawley rats were used for obtaining the brain slices. Both Bomb and NT in pmol ranges stimulated nearly 70% of ARC neurons tested and the effects were all very significant. [D-Trp11]-NT, a NT analog, behaved more like an analog of NT instead of an antagonist, although [Leu13-psi(CH2NH)-Leu14]-Bomb, a Bomb receptor antagonist, could not block most of Bomb's effects on ARC neurons. The significant effects of Bomb and NT shown in this report indicate that both peptides may play significant roles in the neuroendocrine control system.

Morbidity and recurrence with modifications of radical vulvectomy and groin dissection

Vulvar carcinoma has been managed in recent years with modifications of radical vulvectomy and groin dissection. Separate groin incisions, superficial inguinal lymphadenectomy, unilateral groin dissection, and wide excision have been utilized to reduce the morbidity of treatment. In this study, the surgical management of 82 patients with vulvar squamous cell carcinoma was reviewed in order to assess morbidity and risk of recurrence. A modification of radical vulvectomy and groin dissection was employed in 67 patients, while 15 patients underwent classical en-bloc vulvar and groin dissection. Wound complications of the vulva occurred in 1 of 12 patients undergoing hemivulvectomy, in 8 of 55 undergoing radical vulvectomy, and in 7 of 15 who had en-bloc vulvar resection and groin dissection (P = 0.01). Among the 46 patients undergoing bilateral groin dissection through separate incisions, groin breakdown, lymphocyst, and lymphedema occurred in 10 (22%), 7 (15%), and 7 (15%), versus 0, 1 (7%), and 2 (13%) of the 15 who had unilateral groin dissection. Modification of vulvar resection did not increase the risk of local recurrence. Groin recurrence developed in 2 of 15 patients who underwent en-bloc groin dissection and in 1 of 46 who underwent bilateral groin dissection through separate incisions. Two of 15 who had a unilateral groin dissection recurred in the contralateral groin. The risk of recurrence as well as morbidity following modifications of radical vulvectomy with groin dissection should be considered when planning treatment.

The young pioneers: first baccalaureate nursing students in the People's Republic of China

Nursing in the People's Republic of China, like elsewhere, has undergone monumental changes during the 20th century. This paper focuses on one of those changes by examining the professional socialization process of the first class from the first baccalaureate in nursing (BSN) programme in China since 1952. These data from this first BSN class are part of a larger study on professional socialization in which data were collected from four of the recently established 11 BSN programmes in China. To put these data into a historical context, some highlights of Chinese nursing history are noted. These will help us to understand the present-day situation in this the world's most populous nation.

Defining the carbohydrate specificities of Abrus precatorius agglutinin as T (Gal beta 1----3GalNAc) greater than I/II (Gal beta 1----3/4GlcNAc)

The combining site of the nontoxic carbohydrate binding protein (Abrus precatorius agglutinin, APA) purified from the needs of Abrus precatorius (Jequirity bean), was studied by quantitative precipitin and precipitin-inhibition assays. Of 26 glycoproteins and polysaccharides tested, all, except sialic acid-containing glycoproteins and desialized ovine salivary glycoproteins, reacted strongly with the lectin, and precipitated over 70% of the lectin added, indicating that APA has a broad range of affinity and recognizes (internal) Gal beta 1----sequences of carbohydrate chains. The strong reaction with desialized porcine and rat salivary glycoproteins as well as pneumococcus type XIV polysaccharide suggests that APA has affinity for one or more of the following carbohydrate sequences: Thomsen-Friedenreich (T, Gal beta 1----3GalNAc), blood group precursor type I and/or type II (Gal beta 1----3/4GlcNAc) disaccharide determinants of complex carbohydrates. Among the oligosaccharides tested, the T structure was the best inhibitor; it was 2.4 and 3.2 times more active than type II and type I sequences, respectively. The blood group I Ma-active trisaccharide, Gal beta 1----4GlcNAc beta 1----6Gal, was about as active as the corresponding disaccharide (II). From the above results, we conclude that the size of the combining site of the A. precatorius agglutinin is probably as large as a disaccharide and most strongly complementary to the Gal beta 1----3GalNAc (T determinant) sequence. The carbohydrate specificities of this lectin will be further investigated once the related oligosaccharide structures become available.

Low calcium/high magnesium medium increases activities of hypothalamic arcuate and suprachiasmatic neurons in brain tissue slices

Extracellular single-unit recording was conducted in hypothalamic arcuate (ARC) and suprachiasmatic nucleus (SCN) in rat brain slices. The perifusion medium was switched from normal artificial cerebrospinal fluid (ACSF) to ACSF containing low Ca2+ and high Mg2+ to test the effect of extracellular calcium on the spontaneous activities of these neurons and their responses to some test agents. It was found that almost all of the ARC and SCN units tested increased their firing rates in low Ca2+, high Mg2+ ACSF, and exhibited more significant responses to excitatory test agents. The effects of low Ca2+, high Mg2+ ACSF were repeatable and reversible. The results suggest that extracellular Ca2+ is essential in maintaining the membrane stability of most hypothalamic neurons and most agents tested are acting postsynaptically on the unit recorded.

The complete primary structure of abrin-a B chain

The complete 267 amino acid sequence of abrin-a B chain was determined by analysis of peptides obtained by digestion with trypsin, chymotrypsin, lysyl endopeptidase, Staphylococcus aureus V8 protease and thermolysin. The sequence is not identical with that predicted previously by nucleotide sequencing, indicating the presence of isoforms of abrin. Comparison of the amino acid sequence of abrin-a B chain with that of ricin-D B chain reveals a high degree of sequence identity (59%). Abrin-a B chain appears to consist of two domains, each domain with subdomains (alpha, beta, gamma) of about 40 amino acid residues.

Meigs syndrome with elevated serum CA 125

Elevation of serum CA 125 levels is associated with malignant serous ovarian carcinomas and has been described in one patient with Meigs syndrome. We present two additional cases of Meigs syndrome with significant elevations in serum CA 125 and report the results of immunohistochemical staining for CA 125. CA 125 expression was localized to the omentum and peritoneal surfaces rather than the fibroma. We suggest that expression of CA 125 and accumulation of ascites in these two patients may have resulted from some common peritoneal process.

Noma neonatorum: an unusual case of noma involving a full-term neonate

Noma neonatorum is a gangrenous process that occurs in the oral, nasal or anal area and occasionally the eyelids and scrotum of the newborn. The disease is caused by Pseudomonas aeruginosa and usually affects premature ill babies during the first few weeks of life. A full-term neonate with nasal and scrotal noma is uncommon and is therefore reported.

Inhibition of Moloney murine leukemia virus reverse transcriptase activity by tetrahydroxyxanthones isolated from the Chinese herb, Tripterospermum lanceolatum (Hyata)

Five tetrahydroxyxanthones (THXs) isolated from Tripterospermum lanceolatum (Hyata) have been shown to have a strong inhibitory effect on Moloney murine leukemia virus reverse transcriptase (Mo-MLV RT) activity when (rA)n-(dT)15 and (rC)n-(dT)12-18 were used as template-primers. 50% inhibitory concentrations of 1,3,5,6-THX, 2,3,6,7-THX 1,3,6,7-THX, 3,4,5,6-THX, and 3,4,6,7-THX were determined to be 0.15, 0.27, 0.58, 0.12, and 0.12 microM, respectively. Their effects were concentration-dependent, and the mode of inhibition was found to be by competitive inhibition with respect to template-primer. The tetrahydroxyl groups of THXs were shown to be important for their inhibitory activity. Acylation of THXs with various groups resulted in a moderate or strong decrease in their inhibitory activity.

[Ultrastructural observations of the anterior chamber angle tissues in congenital glaucoma]

18 trabeculectomy specimens of congenital glaucoma were examined by light and transmission electron microscopy with the finding that the primary anomalies in congenital glaucoma included the developmental defect of trabecular meshwork, excessive collagen fibrils in the trabecular matrix, shifting forward of ciliary muscle fibers, and persistent mesenchymal tissue in the chamber angle. The authors also pointed out the importance of the secondary lesions of the trabecular meshwork in the pathogenesis of congenital glaucoma.

Macrophage cytotoxicity against Entamoeba histolytica trophozoites is mediated by nitric oxide from L-arginine

The killing of Entamoeba histolytica trophozoites by phagocytes involves oxidative and nonoxidative mediators. In this study, we determine whether L-arginine-derived nitric oxide (NO) is involved in the killing of E. histolytica trophozoites by activated murine macrophages in vitro. Elicited peritoneal and bone marrow-derived macrophages activated with IFN-gamma alone or with IFN-gamma and LPS killed 62 to 73% of amebae, concomitant with increased levels of nitrate (NO2). Depletion of L-arginine by addition of arginase to culture medium abrogated macrophage amebicidal activity. NG-monomethyl L-arginine, an L-arginine analog, competitively inhibited NO2 release and amebicidal activity in a dose-dependent fashion, without affecting H2O2 production; however, the addition of excess L-arginine competitively restored macrophage amebicidal effects. In culture, sodium nitrite and sodium nitroprusside were cytotoxic to E. histolytica and this was reversed by the addition of myoglobin. Exogenously added FeSO4 prevented macrophage cytotoxicity. Addition of superoxide dismutase, a scavenger of O2-, partially inhibited amebicidal activity, without influencing NO2 production. Untreated and LPS-exposed macrophages produced high levels of H2O2 independent from NO2 production and amebicidal effects. However, the addition of catalase, a scavenger of H2O2, inhibited both amebicidal activity and NO2 production by activated macrophages. Our results demonstrate that NO is the major cytotoxic molecule released by activated macrophages for the in vitro cytotoxicity of E. histolytica and that O2- and H2O2 may be cofactors for the NO effector molecule.

Macrophage cytotoxicity against Entamoeba histolytica trophozoites is mediated by nitric oxide from L-arginine

The killing of Entamoeba histolytica trophozoites by phagocytes involves oxidative and nonoxidative mediators. In this study, we determine whether L-arginine-derived nitric oxide (NO) is involved in the killing of E. histolytica trophozoites by activated murine macrophages in vitro. Elicited peritoneal and bone marrow-derived macrophages activated with IFN-gamma alone or with IFN-gamma and LPS killed 62 to 73% of amebae, concomitant with increased levels of nitrate (NO2). Depletion of L-arginine by addition of arginase to culture medium abrogated macrophage amebicidal activity. NG-monomethyl L-arginine, an L-arginine analog, competitively inhibited NO2 release and amebicidal activity in a dose-dependent fashion, without affecting H2O2 production; however, the addition of excess L-arginine competitively restored macrophage amebicidal effects. In culture, sodium nitrite and sodium nitroprusside were cytotoxic to E. histolytica and this was reversed by the addition of myoglobin. Exogenously added FeSO4 prevented macrophage cytotoxicity. Addition of superoxide dismutase, a scavenger of O2-, partially inhibited amebicidal activity, without influencing NO2 production. Untreated and LPS-exposed macrophages produced high levels of H2O2 independent from NO2 production and amebicidal effects. However, the addition of catalase, a scavenger of H2O2, inhibited both amebicidal activity and NO2 production by activated macrophages. Our results demonstrate that NO is the major cytotoxic molecule released by activated macrophages for the in vitro cytotoxicity of E. histolytica and that O2- and H2O2 may be cofactors for the NO effector molecule.

Nucleotide sequence of cDNA for Acacia confusa trypsin inhibitor and implication of post-translation processing

Synthetic oligonucleotides corresponding to all possible sequences of N-terminal and C-terminal region of Acacia confusa trypsin inhibitor were used to generate ACTI-related sequences using the polymerase chain reaction on the cDNAs encoding ACTI of the seeds of legume, A. confusa. The deduced amino acid sequence agreed with that determined by the peptide analysis except an extra amino acid residue, serine, was found at the junction of A and B chain, which was removed by post-translation processing with specific protease(s). The substrate specificity of the protease(s) was found to cleave at the C-terminal sites of asparagine and serine, which was also shown to be the same case for another plant protein, abrin, isolated from legume, Abrus precatorius.

Cellular kinetics, dosimetry, and radiobiology of alpha-particle radioimmunotherapy: induction of apoptosis

Though clinical results for radioimmunoconjugate therapy of most common epithelial tumors have been disappointing, dramatic responses have been observed repeatedly in the treatment of high- and low-grade malignant lymphomas. This high clinical responsiveness after radioimmunoconjugate therapy sometimes appears to be out of proportion to the calculated radiation dose absorbed by the lymphoma tissue. Here we describe some key aspects of the kinetics, dosimetry, and cellular radiobiology of murine lymphoma cells exposed to 212Bi-radiolabeled alpha-particle-emitting immunoconjugates specific for the differentiation antigen Thy 1.2. Approximately 25 cell-bound alpha-particle-emitting immunoconjugates per target cell were required to reduce clonogenic survival by 90% (the radiobiological D10). Serial kinetic analyses of the antibody and radioisotope components of the immunoconjugates revealed significant levels of dechelation and up to 7.5% cellular internalization of the isotope. Cellular radiation dosimetry performed by Monte Carlo computer simulation of alpha-particle energy deposition patterns based on the observed radiopharmacokinetics showed that the D10 resulted from approximately four alpha-particle traversals through the nucleus, corresponding to an absorbed radiation dose of approximately 0.95 Gy to the cell nucleus. Electron micrographs and DNA gel studies of murine lymphoma cells undergoing radioimmunoconjugate therapy in vivo and in vitro demonstrated bizarre blebbing patterns, condensation of chromosomal material, and internucleosomal DNA fragmentation patterns characteristic of programmed cell death (apoptosis). We conjecture that the efficacy of radioimmunoconjugates against responsive cell types may be the result of passive DNA damage by ionizing radiation and the initiation of apoptosis in response to radioimmunotherapy.

Clinical presentation and management of stage I cervical adenocarcinoma: a 25 year experience

In this study, we review the clinical presentation, treatment, and prognosis of 89 patients with stage I cervical adenocarcinoma treated at Strong Memorial Hospital over the past 25 years. In the past decade, the mean age of patients with stage I cervical adenocarcinoma was 44 years, in contrast to a mean of 58 years in the prior interval (P less than 0.001). Prior to 1980 only 4% of patients were of childbearing age, whereas in the past decade 27% were under 35 years old (P = 0.02). The difference in age at presentation cannot be explained by earlier detection, as the fraction of stage I patients, the mean tumor size, and the percentage of clinically occult tumors have not changed. There were no ovarian metastases in 41 patients who underwent oophorectomy. Adenosquamous tumours did not differ in prognosis from pure adenocarcinoma. Grade and lymph node status were significant predictors of outcome. Treatment results have not improved over the past 25 years, and combined therapy with radiation and surgery offered no advantage over radiation alone. Because this tumor is more frequently seen in younger patients, the management of occult adenocarcinoma with early stromal invasion has become problematic. Ovarian conservation has been questioned, and the lack of generally accepted criteria for microinvasive adenocarcinoma has led to radical therapy in patients who might have been adequately treated with local excision. Further study is necessary to guide our recommendations regarding preservation of ovarian function or even childbearing potential in young women.

Trypsin inhibitor from the seeds of Acacia confusa

A trypsin inhibitor (ACTI) was isolated and purified from the seeds of Acacia confusa by gel filtration, and trypsin-Sepharose 4B column affinity chromatography. The molecular weight of ACTI was found to be 21,000 +/- 1,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and amino acid composition analysis. ACTI contained four half-cystine and no methionine residues, and was rich in aspartic acid, glutamic acid, glycine, leucine, and lysine residues. The native trypsin inhibitor was composed of two polypeptide chains, and it inhibited trypsin and alpha-chymotrypsin stoichiometrically at the molar ratio of 1:1 and 2:1, respectively. The amino-terminal sequence analysis of the A. confusa trypsin inhibitor A and B chains revealed a more extensive homology with Acacia elata and silk tree trypsin inhibitors, and a less extensive homology with Kunitz soybean trypsin inhibitor.

The ability of large T antigen to complex with p53 is necessary for the increased life span and partial transformation of human cells by simian virus 40

Simian virus 40 (SV40) T antigen binds to the tumor suppressor p53 protein, and this association may contribute to oncogenic transformation by the virus. We investigated the importance of this binding on transformation by examining three replication-competent mutants of SV40 (402DE, 402DN, and 402DH). These mutants express T antigens defective in binding to human and monkey p53s but retain some binding with mouse p53. All showed significant reduction in their ability to induce transformed cell foci of two normal human cell lines as well as a slight reduction with mouse embryo cells. Other comparable mutants which express T antigens retaining the ability to complex with p53 were able to induce foci at wild-type levels in both human and mouse cells. Further studies were performed with five T-antigen-positive clones isolated from the few human cell foci that appeared after transfection with 402 mutant DNAs. All five clones reached senescence at about the same point as did the parental untransformed cells. However, six other human cell clones obtained after transfection with DNA from nondefective mutants or wild-type virus were still growing well at more than 10 passages beyond their expected life span. These results suggest that the ability of T antigen to form stable complexes with p53 is necessary for SV40 to extend the life span and partially transform human cells in culture.

Stable T-p53 complexes are not required for replication of simian virus 40 in culture or for enhanced phosphorylation of T antigen and p53

We generated a number of simian virus 40 (SV40) mutants with single amino acid substitutions in T antigen between residues 388 and 411. All but one mutant (398LV) replicated like wild-type SV40 and gave rise to normal-size plaques. Three different mutations at residue 402 (Asp to Glu, Asn, or His) totally prevented the formation of stable complexes with the cellular protein p53 in monkey cells but had no effect on virus replication. Only one other mutation in this region, involving residue 401 (Met to Thr), slightly inhibited the formation of T-monkey p53 complexes. The three mutant T antigens with substitutions at residue 402 also formed no stable complexes with human p53 but generated low levels of complexes with mouse p53. These results indicate that residue 402 is critical for binding to monkey and human p53 proteins and is important for binding to mouse p53. We suggest that it is one of several points of contact. In cells infected with any one of the three residue 402 mutant viruses. T antigen and p53 became increasingly phosphorylated, as they were in cells infected with wild-type virus. Our data therefore show that stable T-p53 complexes are not required for replication of SV40 in culture or for enhanced phosphorylation of either protein.

Selective cytotoxic effects of immunotoxin--monoclonal anti-AFP-abrin-A chain conjugate on several human hepatoma cell lines

A highly specific monoclonal antibody (anti-AFP) against alpha-fetoprotein (AFP) was linked to N-succinimidyl-3-(2-pyridyldithio)propionate (SPDP) to form conjugates which were purified with a protein A-sepharose CL-4B affinity column. The conjugate, PDP-Anti-AFP was then covalently coupled to the toxic abrin-A chain to synthesize immunotoxins. The immunotoxin, anti-AFP-abrin-A conjugate, which was also purified with a protein A-sepharose CL-4B affinity column, had a molecular weight of 180,000 and had 80% antigen-binding activity that of anti-AFP activity and 92% toxicity of abrin-A chain. The immunotoxin showed selective cytotoxicities toward the AFP secreting human hepatoma cell lines, such HepG2 and Hep3B, but not toward AFP non-secreting human hepatoma cell line, PLC/PRF/5.

The good nurse: descriptions from the People's Republic of China

This study is based on questionnaire data gathered from 33 students in the first class of the first BSN programme in the People's Republic of China. They were asked to describe the characteristics of a good nurse and characteristics of a bad nurse. These students had just completed their pre-nursing courses and were entering the nursing part of their education. They identified personal qualities, behaviour and knowledge areas as the overall categories for these characteristics.

Transformation by simian virus 40 does not involve the mutational activation of p53 to an oncogenic form

We investigated whether the p53 protein of SV40-transformed mouse cells reacted with the conformation-dependent monoclonal antibody pAb246. This antibody can usually distinguish between a p53 with anti-proliferative activity like the wild-type protein (pAb246+) and a mutated form of p53 with oncogenic activity (pAb246-). Of the 13 cell lines that were screened, 12 contained the pAb246+ form of p53 and one had the pAb246- form. We showed that SV40 did not induce an activating mutation in the p53 of this latter cell line, because the cells from which it was derived were also pAb246-. Cascade immunoprecipitation experiments demonstrated that in three SV40-transformed cell lines that were examined, all of the p53 was of the pAb246+ form making it unlikely that small amounts of pAb246- p53 were responsible for the transformation properties of these cells. We therefore concluded that SV40-mediated transformation of murine cells is not dependent on the activation of their p53 to an oncogenic form, and that, in all probability, transformation is allowed to occur in part because the anti-proliferative activity of p53 is blocked by SV40 T antigen.

Chimeric protein: abrin B chain-trypsin inhibitor conjugate as a new antitumor agent

Abrin B chain and trypsin inhibitor isolated from Acacia confusa (ACTI) were covalently linked to form a chimeric protein (ANB-ACTI) with N-succinimidyl-3-(-2-pyridyldithio)propionate. The chimeric protein had 31% of trypsin inhibitory activity of ACTI and 7% of hemagglutinating activity of abrin B chain, but no inhibition on protein biosynthesis. ANB-ACTI had strong inhibitory effects on the growth of sarcoma 180 cells and Hela cell culture while the mixture of an equivalent amount of free abrin B chain and ACTI did not. The results suggests that abrin B chain of chimeric protein may act as a vector to carry ACTI into the tumor cells. ACTI into the tumor cells. ACTI in the chimeric protein potentiates its antitumor activity as well as its resistance to tryptic digestion.

Experimental use of a low cost liquid crystal TV in multiplex holography

We demonstrate experimentally the use of liquid crystal television to make a multiplex hologram.

Homocysteinemia in rats induced by folic acid deficiency

The effect of folate deficiency on homocysteine metabolism was examined in rats given a folate-deficient diet. Total homocysteine was determined in serum stored at -22 degrees C for 3 wk. All animals in the control group had more than 20 ng.ml-1 of serum folate and more than 1000 pg.ml-1 of serum cyanocobalamin throughout the experimental period. In contrast, serum folate in animals given the folate-deficient diet decreased to less than 3 ng.ml-1 after 4 wk and to less than 2 ng.ml-1 (a subnormal level) after 10 wk of the experiment while serum cyanocobalamin remained at more than 1000 pg.ml-1 throughout the experiment. In the control group, mean serum total homocysteine +/- SD was 4.04 +/- 1.07 nmol.ml-1 during the 20 wk of experiment. At the 10th wk before serum folate reached subnormal levels, the animals given the folate-deficient diet had a mean serum total homocysteine of 7.67 +/- 1.53 nmol.ml-1, demonstrating a significant increase (P less than 0.001). No further significant increase of mean serum total homocysteine concentrations was observed after serum folate became subnormal. This study demonstrated for the first time that a selective deficiency of folic acid caused a 2-4 fold increase in serum total homocysteine when serum folate was at low normal and at subnormal levels in rats.

The detection of mycobacterial DNA sequences in uncultured clinical specimens with cloned Mycobacterium tuberculosis DNA as probes

A plasmid DNA library was constructed from restriction endonuclease digested genomic deoxyribonucleic acid (DNA) of a virulent strain of Mycobacterium tuberculosis isolated from sputum of a patient. The sensitivity and specificity of two of the cloned DNA fragments in detecting M. tuberculosis and its related DNA sequences were analysed by DNA-to-DNA hybridization. The level of detection was determined to be 50 picograms of M. tuberculosis DNA, which is approximately equivalent to 10,000 mycobacterial genomes. These two M. tuberculosis DNA probes did not cross-hybridize to DNA of non-mycobacterial origin, nor with DNA from 9 out of 11 other mycobacterial species. Mycobacterial DNA sequences could be detected in 134 of 441, or 30.4%, of various types of uncultured clinical specimens from 365 patients by the DNA probes, whereas traditional culture method showed only a 19.0% positivity rate for the same specimens (p less than 0.001). The overall sensitivity and specificity of the DNA probes in detecting M. tuberculosis are 90.5% and 83.8% respectively. The DNA hybridization test may become a useful tool for the early and rapid determination of mycobacterial infection in uncultured clinical specimens.