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D E Bruns

Publications and source records attributed to D E Bruns.

At least 19 recordsLinked to original sources

Expression of parathyroid hormone-related peptide (PTH-rp) and its receptorin the porcine ovary: regulation by transforming growth factor-beta and possible paracrine effects of granulosa cell PTH-rp secretion on theca cells.

Parathyroid hormone-related peptide (PTH-rp) and the PTH-rp receptor are expressed in certain cancers as well as in many normal tissues. To evaluate the expression of this Ca(2+)-regulating hormone and its receptor in porcine ovary, we isolated partial cDNAs encoding homologous PTH-rp and PTH-rp receptor using reverse transcription-polymerase chain reaction (RT-PCR). The cDNA encoding PTH-rp (419 base pairs [bp]) was 92% and 87% homologous to human and rat sequences, respectively, while the PTH-rp receptor clone (167 bp) was 94% and 91% identical to the human and rat genes. Qualitative estimates of PTH-rp mRNA by RT-PCR indicated that the PTH-rp gene is expressed at high levels in the corpus luteum but is undetectable in granulosa and theca cells isolated from small (1-5 mm) and medium-sized (5-8 mm) antral follicles. In contrast, PTH-rp receptor transcripts were most abundant in corpora lutea and theca cells, and least abundant (albeit detectable) in granulosa cells. Regulation of PTH-rp protein production was assessed in serum-free monolayer cultures of porcine granulosa cells. Transforming growth factor (TGF)-beta1 (100 ng/ml) increased PTH-rp concentrations (assayed by two-site immunoradiometric assay of culture media) as well as corresponding PTH-rp mRNA accumulation (assessed by RT-PCR) in a time-dependent manner, with maximal responses of 3- to 5-fold at 96 h. TGF-beta1 dose-response studies revealed an ED(50) of 0. 24-0.38 ng/ml with a maximal effect at 30 ng/ml. Other growth factors and hormones, including insulin, insulin-like growth factor (type I), epidermal growth factor, FSH, estradiol, and interleukin-1, failed to alter PTH-rp secretion. Biological effects of PTH-rp were evident in purified porcine theca cells. Using the Ca(2+)-sensitive fluorescent indicator dye, fura-2, and digital imaging videomicroscopy, we found that PTH-rp (1 microM) stimulated intracellular free calcium ion concentrations ([Ca(2+)](i)) in single porcine theca cells. The [Ca(2+)](i) elevation was characterized by a slow and prolonged rise. After PTH-rp stimulation, theca cells maintained responsiveness to hormone stimulation by LH, which elicited a typical theca cell [Ca(2+)](i) response. Our results allow a hypothesis of a paracrine intrafollicular signaling system involving interaction between theca cell-derived TGF-beta and granulosa cell-derived PTH-rp, with feedback by PTH-rp on theca cells. Alternatively, expression of mRNAs encoding PTH-rp and its receptor in corpora lutea suggests that this peptide may play a role in luteal cell function. The precise role of this intraovarian PTH-rp system will require further study.

Animals↗

Toward a checklist for reporting of studies of diagnostic accuracy of medical tests.

BACKGROUND: : "Diagnostic accuracy" refers to the ability of medical tests to provide accurate information about diagnosis, prognosis, risk of disease, and other clinical issues. Published reports on diagnostic accuracy of medical tests frequently fail to adhere to minimal clinical epidemiological standards, and such failures lead to overly optimistic assessments of evaluated tests. Our aim was to enumerate key items for inclusion in published reports on diagnostic accuracy, with a related aim of making the reports more useful for systematic reviews. METHODS: : We examined published reports on shortcomings of studies of diagnostic accuracy. We prepared an initial draft of a checklist to address common errors and presented it at a meeting of editors. After incorporation of comments from editors, we published a revised version in Clinical Chemistry in 1997 for comment from readers. One of us (E.M.) additionally circulated copies of the draft to methodologists and others interested in Evidence-Based Medicine. We updated the checklist with input from these sources. RESULTS: : The updated document lists items for inclusion in the title, abstract, methods, results, and discussion sections of published papers. Depending on the nature of the study, the total number of items for a single paper is approximately 40. We invite comments on this document, which is freely available at Clinical Chemistry Online, where it can accessed readily from the Table of Contents for the July 2000 issue at www. clinchem.org/content/vol46/issue7/. Comments (eLetters) can be posted there for general reading. CONCLUSIONS: : The suggested revisions incorporated in this report appear useful to ensure inclusion of additional information that can allow assessment of the validity of the conclusions and the applicability of the study in other settings. The list can be useful in formulating guidelines and a checklist, which will require testing by authors and study of their effect on published studies of diagnostic accuracy.

Clinical Chemistry Tests↗

Differing susceptibility of echocardiographic contrast agents to adverse effects of biologic factors: multicenter, videodensitometric comparison of octafluoropropane-filled microspheres with air-filled microspheres for left ventricular opacification.

BACKGROUND: Echocardiographic contrast enhancement of the left ventricle has diagnostic value in the assessment of regional and global left ventricular (LV) function. The efficacy of both octafluoropropane-filled human albumin microbubbles (OCTA) and of air-filled human albumin microbubbles (AIR) for LV endocardial delineation and qualitative LV opacification has previously been reported. However, pulmonary disease, obesity, impaired LV function, and decreased echogenicity may diminish the efficacy of contrast agents for LV opacification. The purpose of this study was to compare the susceptibility of 2 contrast agents currently approved by the Food and Drug Administration to these biologic factors. METHODS: To compare quantitative LV opacification with OCTA (0.2, 0. 5, 3.0, 5.0 mL) versus AIR (0.08 mL/kg, 0.22 mL/kg), we performed videodensitometry in 199 patients (average age 59.2 +/- 13.3 years, 79% men) studied in 2 identical, prospective, multicenter, blinded trials, of whom 74 had impaired LV function, pulmonary disease, or both, 70 were obese (body mass index >30 kg/m(2)), and 45 were nonechogenic (>/=4 of 6 endocardial segments were not seen in the apical 4-chamber view). Changes in videodensity from noncontrast to contrast agent with the same gain settings were determined at end diastole and end systole (gray scale 0 to 255 U) for 2 regions of interest: left ventricle apex-to-mid-cavity and mid-cavity-to-base. The relative influence of clinically evident pulmonary disease, impaired LV function on echocardiography, and echogenicity on LV opacification produced by both contrast agents was determined by multivariate analysis. RESULTS: Significant videodensity increases ranging from 67% to 143% were observed with both agents. At the recommended initial doses (0.5 mL for OCTA, 0.22 mL/kg for AIR), OCTA produced greater opacification than AIR in both regions of interest and at both phases of the cardiac cycle. Poor LV function was associated with decreased LV opacification for AIR but not for OCTA. Diminished echogenicity was more strongly associated with impaired opacification for AIR than for OCTA. Obesity and clinically evident pulmonary disease were associated with diminished chamber opacification with both OCTA and AIR. CONCLUSIONS: In addition to the superiority of octafluoropropane-filled microspheres to air-filled microspheres for LV opacification, the efficacy of OCTA is relatively unaffected by impaired LV function and is less susceptible to the effects of poor echogenicity than AIR.

Albumins↗

Dopamine-1 receptor coupling defect in renal proximal tubule cells in hypertension.

The ability of the dopamine-1 (D1)-like receptor to stimulate adenylyl cyclase (AC) and phospholipase C (PLC), inhibit sodium transport in the renal proximal tubule (RPT), and produce natriuresis is attenuated in several rat models of hypertension. Since the inhibitory effect of D1-like receptors on RPT sodium transport is also reduced in some patients with essential hypertension, we measured D1-like receptor coupling to AC and PLC in cultures of human RPT cells from normotensive (NT) and hypertensive (HT) subjects. Basal cAMP concentrations were the same in NT (n=6) and HT (n=4). However, the D1-like receptor agonist fenoldopam increased cAMP production to a greater extent in NT (maximum response=67+/-1%) than in HT (maximum response=17+/-5%), with a potency ratio of 105. Dopamine also increased cAMP production to a greater extent in NT (32+/-3%) than in HT (14+/-3%). The fenoldopam-mediated increase in cAMP production was blocked by SCH23390 (a D1-like receptor antagonist) and by antisense D1 oligonucleotides in both HT and NT, indicating action at the D1 receptor. The stimulatory effects of forskolin and parathyroid hormone-related protein of cAMP accumulation were not statistically different in NT and HT, indicating receptor specificity and an intact G-protein/AC pathway. The fenoldopam-stimulated PLC activity was not impaired in HT, and the primary sequence and expression of the D1 receptor were the same in NT and HT. However, D1 receptor serine phosphorylation in the basal state was greater in HT than in NT and was not responsive to fenoldopam stimulation in HT. These studies demonstrate the expression of D1 receptors in human RPT cells in culture. The uncoupling of the D1 receptor in both rats (previously described) and humans (described here) suggests that this mechanism may be involved in the pathogenesis of hypertension; the uncoupling may be due to ligand-independent phosphorylation of the D1 receptor in hypertension.

Aged↗

Expression and specific immunolocalization of the human parathyroid hormone/parathyroid hormone-related protein receptor in the uteroplacental unit.

OBJECTIVE: Our purpose in these studies was to determine the expression and cellular localization of the parathyroid hormone/parathyroid hormone-related protein receptor in the human uteroplacental unit. STUDY DESIGN: Human uteroplacental tissues were obtained and ribonucleic acid was extracted. Reverse transcriptase-polymerase chain reaction was performed with use of primers for both the parathyroid hormone/parathyroid hormone-related protein receptor and human phosphoglyceraldehyde dehydrogenase. Ethidium bromide-stained gels and Southern blots were evaluated, and polymerase chain reaction fragments were sequenced. For immunohistochemistry, slides were incubated with a newly developed antibody (3D1.1) specific for the parathyroid hormone/parathyroid hormone-related protein receptor, and bound monoclonal antibody was detected by use of the avidin-biotin technique. RESULTS: Reverse transcriptase polymerase chain reaction gels and blots showed that receptor messenger ribonucleic acid was present in choriodecidua, placenta, and myometrium. Sequence analysis revealed complete identity of the receptor product and the known nucleotide sequence in the receptor. There was intense receptor staining of the myometrial smooth muscle as well as staining of the endothelium and smooth muscle of the associated vasculature. In umbilical cord immunoreactive receptor was found in the vascular endothelium and vascular smooth muscle cells and in stromal cells. In choriodecidua receptor was found in chorionic trophoblasts and decidualized endometrial stromal cells. In all tissues immunostaining was specific, as evidenced by the blocking of staining after addition of receptor peptide to the antibody (absorbed controls). CONCLUSION: The parathyroid hormone/parathyroid hormone-related protein receptor is widely expressed in the human uteroplacental unit. The cellular localizations of the receptor in smooth muscle reflect the ability of parathyroid hormone-related protein to relax both uterine and vascular smooth muscle. The presence of novel autocrine and paracrine systems in the human uteroplacental unit is suggested by the finding that the same cells or adjacent cells produce both parathyroid hormone-related protein and its receptor.

Cells, Cultured↗

Mechanical stretch increases secretion of parathyroid hormone-related protein by cultured bladder smooth muscle cells.

Parathyroid hormone-related protein (PTHrP) immunoreactivity has been detected in the bladder and increases in response to dilatation secondary to obstruction. The hypothesis that PTHrP could be increased solely by stretch rather than other possible in vivo variables was tested by stretching cultured bladder smooth muscle cells and analyzing the culture medium for this protein. In response to mechanical stretch, PTHrP was increased in smooth muscle cell cultures. Immunoradiometric assay revealed maximal rates of secretion for the first eight hours. Comparison of percent change in PTHrP secretion of flexed cells for the various flex parameters revealed a difference (p = .006) when the degree of stretch (i.e. percent elongation) was altered. The protein synthesis inhibitor cycloheximide inhibited basal and stretch-induced PTHrP secretion. PTHrP (1-100 nM) relaxed carbachol-contracted bladder body and base by 15% and 45% respectively. PTHrP did not affect bladder contractions induced by potassium (124 mM) or alpha-beta MeATP (10 microM). Increased PTHrP secretion in response to stretch of smooth muscle raises the possibility of an autocrine action to relax the bladder during filling. PTHrP may also exert a paracrine action on vessels regulating blood flow during bladder filling or it may modulate neural activity.

Animals↗

Improved left ventricular endocardial border delineation and opacification with OPTISON (FS069), a new echocardiographic contrast agent. Results of a phase III Multicenter Trial.

OBJECTIVES: The echocardiographic contrast-enhancing effects and safety profile of ALBUNEX (a suspension of air-filled albumin microspheres) were compared with the new contrast agent OPTISON (formerly FS069: a suspension of albumin microspheres containing the gas perfluoropropane) in 203 patients with inadequate noncontrast echocardiograms. BACKGROUND: The efficacy of ALBUNEX has been limited by its short duration of action. By using perfluoropropane instead of air within the microsphere, its duration of action is increased. METHODS: Each patient received ALBUNEX (0.8 and 0.22 mL/kg) and OPTISON (0.2, 0.5, 3.0, and 5.0 mL) on separate days a minimum of 48 hours apart. Echocardiograms were evaluated for increase in left ventricular (LV) endocardial border length, degree of LV opacification, number of LV endocardial border segments visualized, conversion from a nondiagnostic to a diagnostic echocardiogram, and duration of contrast enhancement. A thorough safety evaluation was conducted. RESULTS: Compared with ALBUNEX, OPTISON more significantly improved every measure of contrast enhancement. OPTISON increased well-visualized LV endocardial border length by 6.0+/-5.1, 6.9+/-5.4, 7.5+/-4.7, and 7.6+/-4.8 cm, respectively, for each of the four doses, compared with only 2.2+/-4.5 and 3.4+/-4.6 cm, respectively, for the two ALBUNEX doses (p < 0.001). 100% LV opacification was achieved in 61%, 73%, 87%, and 87% of the patients with the four doses of OPTISON, but in only 16% and 36% of the patients with the two ALBUNEX doses (p < 0.001). Conversion of nondiagnostic to diagnostic echocardiograms with contrast occurred in 74% of patients with the optimal dose of OPTISON (3.0 mL) compared with only 26% with the optimal dose of ALBUNEX (0.22 mL/kg) (p < 0.001). The duration of contrast effect was also significantly greater with OPTISON than with ALBUNEX. In a subset of patients with potentially poor transpulmonary transit of contrast (patients with chronic lung disease or dilated cardiomyopathy), OPTISON more significantly improved the same measures of contrast enhancement compared with ALBUNEX and did so to the same extent as in the overall population. Side effects were similar and transient with the two agents. CONCLUSION: OPTISON appears to be a safe, well-tolerated echocardiographic contrast agent that is superior to ALBUNEX.

Albumins↗

Coexpression of parathyroid hormone-related protein and its receptor in breast carcinoma: a potential autocrine effector system.

Parathyroid hormone-related protein (PTHrP), the pathogenic factor in most cases of humoral hypercalcemia of malignancy, is also expressed by many normal tissues. Its diverse biologic activities in these tissues are mediated by the PTH/PTHrP receptor through autocrine and paracrine mechanisms. Recent data suggest that PTHrP and its receptor might also influence the growth and metastatic spread of some cancers through similar local actions. Accordingly, immunohistochemical studies using murine monoclonal antibodies to detect coexpression of PTHrP and the PTH/PTHrP receptor were performed on 52 invasive breast carcinomas to assess the existence of this potential autocrine effector system. All of the 52 invasive breast carcinomas expressed reactivity for PTHrP, and 50 (96%) of these tumors also expressed reactivity for the receptor. Although additional investigations are necessary for evaluation of the role of PTHrP and PTH/PTHrP receptor in tumor pathogenesis, our current study demonstrates the presence of this potential autocrine effector system in the great majority of invasive breast carcinomas.

Adult↗

Molecular and immunological detection of circulating tumor cells and micrometastases from solid tumors.

Histological, immunological, and molecular methods have been used for detecting micrometastases from nonhematopoietic malignancies. Early studies utilizing cytological methods to identify circulating tumor cells demonstrated the uncertain significance of micrometastasis detection for predicting eventual recurrent disease. Recently, reverse transcriptase-polymerase chain reaction (RT-PCR) for the detection of circulating tumor cells has been suggested as a potential technique for staging of cancer. Studies using RT-PCR thus far indicate that test results may be negative in some patients with known metastatic disease, thereby raising doubts about the utility of the method for staging of disease. In this review, we survey the relevant literature and discuss the range of current applications of histological, immunological, and molecular methods for detecting micrometastases from solid tumors in blood, bone marrow, and lymph nodes and the progress toward determining the significance of micrometastasis detection.

Bone Marrow↗

Interleukin-1 beta and interleukin-4 increase parathyroid hormone-related protein secretion by human umbilical vein endothelial cells in culture.

OBJECTIVE: Our purpose was to learn whether cytokines such as interleukin-1 beta and related (or antagonistic) cytokines, hormones, and growth factors could regulate secretion of the vasorelaxant parathyroid hormone-related protein in human umbilical vein endothelial cells in culture. STUDY DESIGN: Secondary cultures of human umbilical vein endothelial cells were grown to confluence and treated with interleukin-1 beta, an array of factors with possible regulatory actions (cytokines, growth factors, vasoactive peptides, and steroids), and a phorbol ester as a stimulatory control. After 24 hours immunoreactive parathyroid hormone-related peptide in the media was measured by a two-site sandwich radioimmunoassay. The mechanism of interleukin-1 beta action was probed with interleukin-1 beta receptor antagonist and selected inhibitors. RESULTS: Interleukin-1 beta (10 ng/ml) produced up to an eightfold increase in parathyroid hormone-related peptide secretion from human umbilical vein endothelial cells in culture (p < 0.01). Half-maximal stimulation was seen at 0.23 ng/ml. Interleukin-1 receptor antagonist, cycloheximide, and actinomycin D blocked the effects of interleukin-1 beta (p < 0.05). Interleukin-4 at 10 ng/ml and phorbol 12-myristate 13-acetate at 10(-7) mol/L significantly increased the secretion of parathyroid hormone-related peptide by human umbilical vein endothelial cells (p < 0.05). The time course of each interleukin showed an effect beyond 12 hours. The effects of interleukin-1 beta and interleukin-4 appeared to be specific, because a large series of related interleukins and other growth factors and cytokines were without effect. CONCLUSION: Interleukin-1 beta and interleukin-4 increase parathyroid hormone-related protein secretion in human umbilical vein endothelial cells in culture. Because interleukin-1 beta messenger ribonucleic acid has been found in umbilical cord endothelial cells, we propose that the umbilical cord has a novel vasorelaxant regulatory system that uses interleukin-1 beta endothelial action and secretion of the vasorelaxant parathyroid hormone-related peptide.

Cells, Cultured↗

Expression of parathyroid hormone-related peptide and its receptor messenger ribonucleic acid in human amnion and chorion-decidua: implications for secretion and function.

OBJECTIVE: Our purpose was to define the location and packaging of parathyroid hormone-related peptide in amnion-chorion and the potential target tissues for its action in fetal membranes. STUDY DESIGN: We studied fetal membranes by use of light microscopic immunocytochemistry with three monoclonal antibodies against distinct regions of the parathyroid hormone-related peptide molecule. For electron microscopy immunogold analysis with a monoclonal antibody specific to the 109-141 fragment was used to observe parathyroid hormone-related peptide intracellularly in amnion membrane and in the chorion layers. Multiplex reverse transcriptase-polymerase chain reaction with Southern blotting was used to identify parathyroid hormone/parathyroid hormone-related peptide receptor and control messenger ribonucleic acids in amnion and chorion-decidua. RESULTS: All monoclonal antibodies revealed immunoreactive parathyroid hormone-related peptide in the amniotic epithelial cells and in some fibroblast-like cells embedded in the extracellular matrix of the amnion. Parathyroid hormone-related peptide was also found in the chorion in fibroblast and trophoblast layers and in decidua. Ultrastructurally immunogold particles were evenly distributed throughout the amniotic epithelial cells and were present in apical microvilli and near the basal membranes. Electron microscopy studies of the chorion cytotrophoblast also showed freely dispersed immunogold particles of parathyroid hormone-related peptide with no packaging in secretory granules. Low to undetectable levels of parathyroid hormone/parathyroid hormone-related peptide receptor messenger ribonucleic acid were found in amnion tissue, whereas abundant receptor messenger ribonucleic acid was found in chorion-decidua. CONCLUSIONS: These results suggest the presence of a parathyroid hormone-related peptide paracrine system within the human fetal membranes.

Amnion↗

The effect of radiofrequency catheter ablation on myocardial creatine kinase activity.

INTRODUCTION: The primary mechanism of myocardial injury during radiofrequency (RF) catheter ablation in the heart is presumed to be thermal. Creatine kinase has been measured in serum to assess the volume of myocardial injury after ablation. However, its thermal inactivation by RF ablation could lead to underestimation of the true volume of injury. METHODS AND RESULTS: Serial RF lesions were created in 10 canine left ventricles in vivo, and serial serum creatine kinase activities were measured and compared to lesion volume. To assess the stability of myocardial creatine kinase during RF catheter ablation, 29 RF ablations were made on the epicardial surface of porcine left ventricle in vivo and a 2-mm core biopsy was rapidly removed. The cores were rapidly frozen, sectioned longitudinally in 1-mm slices, and homogenized in 0.3 M Tris buffer solution containing EDTA and dithiothreitol for subsequent analysis of creatine kinase activity. An additional 19 tissue cores from RF lesions were stained and used to determine mean lesion depth. Normal tissue biopsies were exposed to 60 seconds of hyperthermia (37 degrees to 85 degrees C, n = 190), or high-density RF current at 50 degrees C (0 to 100 mA/mm2, n = 50), and tissue creatine kinase activity was measured. There was no evidence of creatine kinase washout within the first 2 hours, and peak values were measured 5 to 7 hours postablation. Tissue creatine kinase activity in the first mm depth of RF lesions averaged 10% of control values and increased over the first 5 mm of lesion depth. The mean creatine kinase activity within the hemisphere of ablated myocardium was calculated to be 31% of control. Creatine kinase activity declined significantly at temperatures above 65 degrees C, but no difference in tissue creatine kinase activity was observed among differing levels of RF current exposure in the absence of significant heating. CONCLUSIONS: Creatine kinase activity in myocardial tissue is significantly diminished within the RF lesion. Creatine kinase activity is not stable at temperatures above 65 degrees C, which are routinely achieved within the central zone of RF ablation, and is unaffected by RF current in the absence of hyperthermia. Measurements of serum creatine kinase activity after RF catheter ablation may significantly underestimate the volume of myocardial injury.

Animals↗

Measurement of methemoglobin in neonatal samples containing fetal hemoglobin.

Because of the potential for methemoglobinemia during nitric oxide therapy in newborns, methods are needed to accurately quantify methemoglobin (MetHb) in the presence of the high concentrations of fetal hemoglobin (Hb F), bilirubin, and lipids seen in these patients. Spectral differences between fetal and adult Hbs invalidate assumptions of conventional multiwavelength Hb photometry, so we evaluated an "overdetermined" system (Ciba-Corning Model 270), in which absorbances at seven wavelengths are measured to quantify four Hb derivatives. Adult and umbilical cord blood (Hb F 96%) samples were prepared to contain known MetHb fractions. Measured MetHb was linear in cord blood to > or = 15% MetHb. Within-run precision (CV) was < 2.2% (n = 10) at each of seven MetHb fractions between 5% and 100%. Measured (y) and expected (x) MetHb fractions in cord blood were in good agreement (y = 1.0200x + 0.100, Sylx = 0). Added bilibrubin (200 mg/L serum) and lipid (30 g/L) did not interfere. No significant differences were seen for adult and cord blood samples with identical MetHb fractions (P = 0.72), whereas a significant difference was noted with an exactly determined system (P = 0.0033). At clinically relevant MetHb fractions (< 15%), a trend towards increased values in cord blood was noted with an exactly determined system (y = 1.0520x + 0.7600). We conclude that this overdetermined system measures MetHb accurately in samples from patients with large concentrations of Hb F.

Adult↗

Expression of parathyroid hormone-related protein and its receptor in human umbilical cord: evidence for a paracrine system involving umbilical vessels.

OBJECTIVE: Our purpose was to study the expression and localization of parathyroid hormone-related protein and expression of the parathyroid hormone/parathyroid hormone-related protein receptor in human umbilical cord. STUDY DESIGN: The expression and localization of parathyroid hormone-related protein and expression of the parathyroid hormone/parathyroid hormone-related protein receptor were studied in isolated tissues from the human umbilical cord by Northern analysis, reverse-transcriptase polymerase chain reaction, Southern gel analysis, and immunolocalization procedures at the light and electron microscopic levels. RESULTS: Parathyroid hormone-related protein was abundantly expressed in the umbilical cord. Immunohistochemical and immunocytochemical techniques confirmed hormone localization in the amnion epithelial layer and in vascular smooth muscle and endothelial cells in vessels from the umbilical cord and placental chorionic plate. Multiplex reverse-transcriptase polymerase chain reaction identified expression of receptor messenger ribonucleic acid in vessels of the umbilical cord; this finding was verified by means of Southern gel analysis of the products of the reverse-transcriptase polymerase chain reaction. CONCLUSION: A parathyroid hormone-related protein paracrine system appears to exist in human umbilical cord. We suggest that it may be involved in the control of fetal placental circulation.

Endothelium, Vascular↗

Serum amylase isoenzymes in ectopic pregnancy.

In general, significant amylase elevation was not documented in women with tubal pregnancies, compared with normal IUPs in the first trimester and a nonpregnant control range. One of 49 samples in 25 patients with tubal pregnancy was mildly elevated for salivary amylase.

Amylases↗