Endocrine systems in juvenile anadromous and landlocked Atlantic salmon (Salmo salar): seasonal development and seawater acclimation

The present study compares developmental changes in plasma levels of growth hormone (GH), insulin-like growth factor I (IGF-I) and cortisol, and mRNA levels of their receptors and the prolactin receptor (PRLR) in the gill of anadromous and landlocked Atlantic salmon during the spring parr-smolt transformation (smoltification) period and following four days and one month seawater (SW) acclimation. Plasma GH and gill GH receptor (GHR) mRNA levels increased continuously during the spring smoltification period in the anadromous, but not in landlocked salmon. There were no differences in plasma IGF-I levels between strains, or any increase during smoltification. Gill IGF-I and IGF-I receptor (IGF-IR) mRNA levels increased in anadromous salmon during smoltification, with no changes observed in landlocked fish. Gill PRLR mRNA levels remained stable in both strains during spring. Plasma cortisol levels in anadromous salmon increased 5-fold in May and June, but not in landlocked salmon. Gill glucocorticoid receptor (GR) mRNA levels were elevated in both strains at the time of peak smoltification in anadromous salmon, while mineralocorticoid receptor (MR) mRNA levels remained stable. Only anadromous salmon showed an increase of gill 11beta-hydroxysteroid dehydrogenase type-2 (11beta-HSD2) mRNA levels in May. GH and gill GHR mRNA levels increased in both strains following four days of SW exposure in mid-May, whereas only the anadromous salmon displayed elevated plasma GH and GHR mRNA after one month in SW. Plasma IGF-I increased after four days in SW in both strains, decreasing in both strains after one month in SW. Gill IGF-I mRNA levels were only increased in landlocked salmon after 4days in SW. Gill IGF-IR mRNA levels in SW did not differ from FW levels in either strain. Gill PRLR mRNA did not change after four days of SW exposure, and decreased in both strains after one month in SW. Plasma cortisol levels did not change following SW exposure in either strain. Gill GR, 11beta-HSD2 and MR mRNA levels increased after four days in SW in both strains, whereas only the anadromous strain maintained elevated gill GR and 11beta-HSD2 mRNA levels after one month in SW. The results indicate that hormones and receptors of the GH and cortisol axes are present at significantly lower levels during spring development and SW acclimation in landlocked relative to anadromous salmon. These findings suggest that attenuation of GH and cortisol axes may, at least partially, result in reduced preparatory upregulation of key gill ion-secretory proteins, possibly a result of reduced selection pressure for marine adaptations in landlocked salmon.     

A monokine regulates colony-stimulating activity production by vascular endothelial cells

Human umbilical vein endothelial cells were cultured in supernatants of peripheral blood monocytes that had been cultured for 3 days with and without lactoferrin. Colony-stimulating activity (CSA) was measured in supernatants of the endothelial cell cultures and appropriate control cultures using normal, T-lymphocyte-depleted, phagocyte-depleted, low- density bone marrow cells in colony growth (CFU-GM) assays. Monocyte- conditioned medium contained a nondialyzable, heat labile factor that enhanced 4-15--fold the production of CSA by endothelial cells. The addition of lactoferrin to monocyte cultures reduced the activity of this monokine by 69%. Lactoferrin did not inhibit CSA production by monokine-stimulated endothelial cells. Therefore, vascular endothelial cells are potent sources of CSA, the production of CSA by these cells is regulated by a stimulatory monokine, and the production and/or release of the monokine is inhibited by lactoferrin, a neutrophil- derived putative feedback inhibitor of granulopoiesis. Inasmuch as a similar monokine is known to stimulate CSA production by fibroblasts and T lymphocytes, we suggest that mononuclear phagocytes play a pivotal role in the regulation of granulopoiesis by recruiting a variety of cell types to produce CSA.     

Growth factor- and cyclic nucleotide-induced proliferation of normal and malignant mammary epithelial cells in primary culture

Sustained growth of normal mouse mammary epithelial cells in primary culture, leading to an increase in cell number, in response to growth factors [epidermal growth factor (EGF) and fibroblast growth factor (FGF)] or cholera toxin has been achieved by embedding the cells inside collagen cells. Inclusion of agents known to increase the level of cellular cAMP have been found to be favorable for mammary epithelial cell proliferation. Cholera toxin is by far the best of all of the agents tested (prostaglandins E1 and E2, isoproterenol, theophylline, and dibutyryl cAMP). When growth factors (EGF or FGF) are added with cholera toxin, a synergistic effect resulting in a response much greater than with either of them alone is seen. This synergism was best seen in normal mammary epithelial cells from nonpregnant mice. The extent of this synergistic effect was found to be less in normal cells from pregnant mice, suggesting that these cells may be less responsive to EGF during pregnancy. Tumor cells were found to be rather inconsistent in their responses to EGF and cholera toxin, ranging from a minimal response, similar to that of normal cells from pregnant animals, to a maximal response, similar to that of normal cells from nonpregnant animals.     

Kinds of mutations formed when a shuttle vector containing adducts of (+/-)-7 beta, 8 alpha-dihydroxy-9 alpha, 10 alpha-epoxy-7,8,9, 10-tetrahydrobenzo[a]pyrene replicates in human cells.

We have investigated the kinds of mutations induced when a shuttle vector containing covalently bound residues of (+/-)-7 beta, 8 alpha-dihydroxy-9 alpha, 10 alpha-epoxy-7,8,9, 10-tetrahydrobenzo[a]pyrene (BPDE) replicates in human cells. A human embryonic kidney cell line, 293, was used as the eukaryotic host. The target gene for mutation analysis, supF, codes for a tyrosine suppressor tRNA and is strategically located between the origin of replication of the plasmid in Escherichia coli and the gene for a selectable marker, so that the possibility of recovering supF mutants containing gross rearrangements is low. The frequency of supF mutants obtained when untreated plasmid replicated in 293 cells was 1.4 X 10(-4). The frequency with BPDE-treated plasmid increased linearly as a function of the number of adducts, with 16 adducts per plasmid giving 38 X 10(-4). Polyacrylamide gel and agarose gel electrophoresis analysis of 137 plasmids with mutations in the supF gene indicated that 70% (21/30) from untreated plasmids contained deletions or insertions or showed altered gel mobility, whereas only 28% (30/107) of those derived from BPDE-treated plasmids contained such alterations. Of the 86 unequivocally independent mutants derived from BPDE-treated plasmids that were analyzed by sequencing, the majority (60/86) exhibited base substitutions. Mutants exhibiting frameshifts (insertions or deletions of one, two, or four base pairs) were also found, but they were a minority (11/86). In the progeny of BPDE-treated plasmids 61/71 base substitutions observed were transversions, with 45/61 G X C----T X A. Examination of the location of BPDE-induced mutations among the 85 base pairs in the structure of the tRNA revealed that 30% of the base substitutions occurred at two sites and 44% of the rest occurred at five other hot spots. Only 20% of all these base changes involved a site in which a guanine containing a BPDE adduct is predicted to be labile--i.e., a guanine that has a pyrimidine to its 5' side.     

Idiopathic cholangiopathy in a biliary cast syndrome necessitating liver transplantation following head trauma

The development of total biliary casts is very unusual, especially in patients who have not undergone liver transplantation. The aetiology of these casts is uncertain but several factors are believed to play a role, including periods of fasting, haemolysis, cholangitis and recent surgery. Resultant bile stasis and/or gallbladder hypocontractility promote sludge and subsequent stone formation. Here we present the case of a previously well 66-year-old woman who developed a total biliary cast several weeks after being involved in a road traffic accident during which she sustained head injuries but no obvious liver insult. This cast was removed at laparotomy but the patient had resultant diffuse biliary tree abnormalities and persistent cholestasis and subsequently required a liver transplant. The possible aetiologies of biliary cast formation and subsequently cholangiopathy necessitating transplantation in this patient are described.     

再发骨质疏松性椎体压缩骨折保守治疗患者出院后生存质量

目的：对比初次和再发骨质疏松性椎体压缩骨折(osteoporotic vertebral compression fractures,OVCFs)患者保 守治疗的生存质量,了解再次骨折对此类患者生存质量各方面的影响。方法：回顾性观察治疗OVCFs后出现再骨折 的患者30名(再骨折组)和同时期行保守治疗OVCFs后未发生再骨折的基本条件相似的患者30例(对照组),比较两组出 院后3个月时SF-36简明健康健康状况调查表的调查结果。结果：再骨折组治疗后的8个维度均不同程度较对照组变差 (均P<0.01)。结论：再骨折组患者的生存质量明显低于对照组,并且会进一步影响患者的心理预期、情绪和社会活动 的各个方面。     

Pyridine extractability of acid-fastness from Mycobacterium leprae.

Various mycobacteria were tested for their ability to retain acid-fastness after treatment with pyridine: a) Mycobacterium leprae separated from organs of 20 experimentally infected armadillos (which were sacrificed); b) M. leprae separated from a biopsy of a lepromatous patient; c) direct smears of lepromatous tissues from armadillos; d) eighteen cultivable mycobacteria obtained from the American Type Culture Collection (ATCC); E) cultivatable mycobacteria separated from the lymph nodes of a wild-caught armadillo and also the same organism grown in culture and Skinsnes' alleged M. leprae culture. A loss of acid-fastness was observed microscopically from M. leprae separated from experimentally infected armadillo tissues, M. leprae separated from a lepromatous patient biopsy, and M. leprae found in direct smears prepared from infected armadillo tissues. The eighteen cultivatable mycobacteria from ATCC, cultivatable mycobacteria separated from the tissue of a wild-caught armadillo (and also grown in culture) and Skinsnes' alleged M. leprae culture retained their acid-fastness. Testing of pyridine extractability of acid-fastness combined with those of D-DOPA oxidase testing proved to be extremely reliable in our laboratory in differentiating M. leprae from other mycobacteria.