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1.
Diabet Med ; 35(3): 381-385, 2018 03.
Article in English | MEDLINE | ID: mdl-28755389

ABSTRACT

BACKGROUND: Glucagon-like peptide-1 receptor agonists, such as dulaglutide, exenatide and liraglutide, are approved to treat Type 2 diabetes mellitus. Although these drugs provide substantial glycaemic control, studies in rodents have prompted concerns about the development of medullary thyroid carcinoma. These data are reflected in the US package insert, with boxed warnings and product labelling noting the occurrence of these tumours after clinically relevant exposures in rodents, and contraindicating glucagon-like peptide-1 receptor agonist use in people with a personal or family history of medullary thyroid carcinoma, or in people with multiple endocrine neoplasia type 2. However, there are substantial differences between rodent and human responses to glucagon-like peptide-1 receptor agonists. This report presents the case of a woman with pre-existing medullary thyroid carcinoma who exhibited no significant changes in serum calcitonin levels despite treatment with dulaglutide 2.0 mg for 6 months in the Assessment of Weekly AdministRation of LY2189265 [dulaglutide] in Diabetes-5 clinical study (NCT00734474). CASE REPORT: Elevated serum calcitonin was noted in a 56-year-old woman with Type 2 diabetes mellitus at the 6-month discontinuation visit in a study of long-term dulaglutide therapy. Retroactive assessment of serum collected before study treatment yielded an elevated calcitonin level. At 3 months post-study, calcitonin level remained elevated; ultrasonography revealed multiple bilateral thyroid nodules. Eventually, medullary thyroid carcinoma was diagnosed; the woman was heterozygous positive for a germline RET proto-oncogene mutation. CONCLUSION: The tumour was not considered stimulated by dulaglutide therapy because calcitonin remained stable throughout.


Subject(s)
Calcitonin/metabolism , Carcinoma, Neuroendocrine/complications , Diabetes Mellitus, Type 2/drug therapy , Glucagon-Like Peptides/analogs & derivatives , Hypoglycemic Agents/therapeutic use , Immunoglobulin Fc Fragments/therapeutic use , Recombinant Fusion Proteins/therapeutic use , Thyroid Neoplasms/complications , Diabetes Mellitus, Type 2/complications , Drug Substitution , Female , Glucagon-Like Peptides/therapeutic use , Humans , Middle Aged , Proto-Oncogene Mas
2.
Am J Respir Crit Care Med ; 149(4 Pt 1): 1005-11, 1994 Apr.
Article in English | MEDLINE | ID: mdl-8143035

ABSTRACT

Aberrant pulmonary arterial flow has been associated with pulmonary hypoplasia, which is a common cause of death in newborns. The current experiments were designed to confirm whether interruption of postductal main pulmonary artery (MPA) flow causes pulmonary hypoplasia. In addition, the effect of fetal surgery on lung growth was investigated. Fetal sheep, instrumented at 107 to 115 d gestation (MPA ligated [n = 5], sham operated [n = 3], and monitored [no thoracotomy, n = 5]), and unoperated twin fetuses (140-d controls, n = 5) were used for analysis of lung growth at 136 to 140 d gestation. Morphometric measurement of lung tissue volumes and assays of DNA, protein, and saturated phosphatidylcholine (SPC) were used to assess lung growth. MPA ligation significantly decreased lung growth and maturation as indicated by decreased surface area and volumes of fine nonparenchyma, future airspace, and parenchymal tissue, and by decreased lung weights, total DNA, protein, and SPC content. There was a significant increase in the volume percentage of coarse nonparenchyma and a decrease in the volume percentage of future airspace. The pattern of lung growth after MPA ligation suggests that growth of peripheral airspace and parenchymal tissue components does not occur, resulting in a significant decrease in the amount of new tissue formed and delayed tissue maturation. Fetal surgery significantly changed only DNA, protein, and SPC content. Studies of the regulation of lung growth must consider the role of pulmonary arterial flow and the smaller, but significant effects of fetal surgery.


Subject(s)
Lung/embryology , Pulmonary Circulation , Sheep/embryology , Analysis of Variance , Animals , Cesarean Section , DNA/metabolism , Female , Fetal Monitoring , Fetal Organ Maturity , Ligation , Lung/metabolism , Lung/surgery , Phosphatidylcholines/metabolism , Pregnancy , Proteins/metabolism , Pulmonary Artery/embryology , Pulmonary Artery/surgery , Thoracotomy
4.
In Vitro Cell Dev Biol ; 27A(9): 713-9, 1991 Sep.
Article in English | MEDLINE | ID: mdl-1917791

ABSTRACT

Epithelial cells were isolated from mouse endometrium and cultured on two types of extracellular matrix, namely, rat-tail collagen (type I) gels and basement membrane extract (BME) derived from the Engelbreth-Holm-Swarm murine sarcoma. Cell attachment in serum-free medium during the initial 24 h after seeding was approximately twofold higher on BME compared with collagen type I. Addition of serum to the medium enhanced cell attachment on both matrices. On both collagen and BME, uterine cells grew as smooth-bordered colonies, and within a week of culture the cells became cuboidal to columnar in shape. Electron microscopy revealed the presence of apical microvilli associated with a glycocalyx, junctional complexes, tonofilaments, short strands of undilated endoplasmic reticulum, Golgi complex, and lipid droplets. However, cells on BME showed a higher degree of differentiation as assessed by occasional formation of small patches of basement membranelike structure subjacent to the flattened basal surface and formation of glandlike structures within the matrix. Proliferation of these cells as measured by radioactive thymidine incorporation into DNA was increased threefold by addition of epidermal growth factor (EGF) and insulin to the medium, but was not changed by 17 beta-estradiol. The expression of progesterone receptors by uterine epithelial cells grown on both matrices was doubled by addition of EGF and estradiol to the medium.


Subject(s)
Basement Membrane/physiology , Collagen/physiology , Extracellular Matrix/physiology , Uterus/cytology , Animals , Basement Membrane/chemistry , Cell Differentiation/drug effects , Cell Differentiation/physiology , Cell Division/drug effects , Cell Division/physiology , Cells, Cultured , DNA/metabolism , Endometrium/cytology , Endoplasmic Reticulum/ultrastructure , Epidermal Growth Factor/pharmacology , Epithelial Cells , Epithelium/physiology , Epithelium/ultrastructure , Estradiol/pharmacology , Extracellular Matrix/chemistry , Female , Golgi Apparatus/ultrastructure , Insulin/pharmacology , Intercellular Junctions/ultrastructure , Mice , Microscopy, Electron , Microvilli/ultrastructure , Receptors, Progesterone/drug effects , Receptors, Progesterone/metabolism , Thymidine/metabolism , Uterus/physiology , Uterus/ultrastructure
5.
Pediatr Res ; 27(2): 122-7, 1990 Feb.
Article in English | MEDLINE | ID: mdl-2314940

ABSTRACT

Pulmonary hypoplasia has been associated with absent or hypoplastic pulmonary artery in four cases in humans. Despite these reports, the effects of decreased pulmonary arterial flow on fetal lung growth have not been adequately studied. This study defines the effects of left pulmonary artery (LPA) ligation on fetal lung growth in sheep by comparing morphometrically determined pulmonary volumes from LPA-ligated, sham-operated, and un-operated control fetuses. LPA ligation (n = 5) or sham operation (n = 4) was performed at 105- to 114-d gestation. lungs were intratracheally fixed for light microscopy. At 112 d (n = 4) and at 140 d (n = 4), unoperated control fetuses were similarly delivered. Absolute pulmonary volumes were then measured using standard stereologic methods. Normal growth of the left lung from 112 to 140 d resulted in significant increases in wet and dry wt, displacement volume, and volumes of future airspace and capillary contents. LPA ligation caused significant decreases in left lung wet and dry wt, displacement volume, and in absolute volumes of fine nonparenchymal, future airspace, parenchymal tissue, and capillary contents compared to sham-operated and 140-d controls. Parenchymal tissue volume was also less than in 112-d controls. In addition, lung wt, displacement volume, and future airspace volume were significantly decreased in sham-operated fetuses compared to 140-d controls. The effects of LPA ligation on bronchial collateral circulation and factors known to affect lung growth (i.e. lung fluid volume) remain to be determined. Clearly, during the canalicular and alveolar stage of fetal lung development, pulmonary arterial flow is necessary for normal lung growth.


Subject(s)
Fetus/blood supply , Lung/embryology , Pulmonary Artery/physiology , Animals , Embryonic and Fetal Development , Female , Fetus/anatomy & histology , Ligation , Lung/abnormalities , Pregnancy , Pulmonary Artery/abnormalities , Regional Blood Flow , Sheep
6.
J Morphol ; 199(1): 23-40, 1989 Jan.
Article in English | MEDLINE | ID: mdl-2921770

ABSTRACT

The lungs of the New Caldeonian gecko Rhacodactylus leachianus were examined by means of gross dissection and light and electron microscopy. This tropical species, which is the largest living gecko, possesses two simple, single-chambered lungs. Right and left lungs are of similar size and shape. The lung volume (27.2 ml.100 g-1) is similar to that of the tokay (Gekko gecko) but differs in that the gas exchange tissue is approximately homogeneously distributed, and the parenchymal units (ediculae) are very large, approximately 2 mm in diameter. The parenchymal depth varies according to the location in the lung, being deepest near the middle of the lung and shallowest caudally. Scanning and transmission electron microscopy reveal an unusual distribution of ciliated cells in patches on the edicular walls as well as on the trabeculae. Secretory cells are very numerous, particularly in the bronchial epithelium, where they greatly outnumber the ciliated cells. The secretory cells form a morphological continuum characterized by small secretory droplets apically and large vacuoles basally. This continuum includes cells resembling type II pneumocytes but which are devoid of lamellar bodies. Type I pneumocytes similar to those of other reptiles cover the respiratory capillaries, where they form a thin, air-blood barrier together with the capillary endothelial cells and the fused basement laminae. The innervation, musculature, and vascular distribution in R. leachianus are also characterized. Apparent simplification of the lungs in this taxon may be related to features of its sluggish habits, whereas peculiarities of cell and tissue composition may reflect demands of its mesic habitat.


Subject(s)
Lizards/anatomy & histology , Lung/anatomy & histology , Animals , Connective Tissue/anatomy & histology , Connective Tissue/ultrastructure , Lung/ultrastructure , Microscopy, Electron , Muscle, Smooth/anatomy & histology , Muscle, Smooth/ultrastructure , Pulmonary Circulation , Trachea/anatomy & histology , Trachea/ultrastructure
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