bluuebunny/crossref_metadata_2025_split huggingface dataset:
Steroid characteristics of mineralocorticoid adrenocortical hypertension
Authors: Biglieri E G , Kater C E 
Published: January 2020

Abstract
Adrenocortical causes of hypertension are established by examining the mineralocorticoid hormones produced in the zona glomerulosa and zona fasciculata. In the zona glomerulosa, aldosterone excess leads to hypertension, hypokalemia, and suppressed plasma renin activity, with increased concentrations of urinary aldosterone (either as the 18-glucuronide or free aldosterone) as an index of its production. Identifying a tumor by computed tomography scan verifies the diagnosis of a correctable lesion. If no tumor is found, several maneuvers are used to identify primary adrenal hyperplasia, a disorder with autonomous aldosterone production, for which reduction of adrenal mass is curative. The zona fasciculata has two major pathways: the 17-deoxy pathway, where deoxycorticosterone (DOC) and corticosterone are the significant steroids, and the 17-hydroxy pathway, which leads to cortisol production. Tumors of the 17-deoxy pathway, DOC-producing adenomas, have increased concentrations of DOC and its precursor steroids, normal concentrations of cortisol, and suppression of aldosterone production secondary to suppression of the renin system. Two enzymatic defects in the zona fasciculata, 11 beta- and 17 alpha-hydroxylase deficiency, can be first readily identified by the virilization in the former, hypogonadal features in the latter. Steroid patterns are diagnostic. DOC is produced in excess in both deficiencies and is the cause of the hypertension. Deficient or impaired 11 beta-hydroxy steroid dehydrogenase in the apparent mineralocorticoid excess syndrome or after licorice ingestion retards the conversion of cortisol to inactive cortisone in the kidney, leading to mineralocorticoid hypertension; this leads to suppression of the renin system and subsequently of aldosterone.
Clinical evaluation and differential diagnosis of the individual hypertensive patient
Authors: Mueller F B , Laragh J H 
Published: January 2020

Abstract
This paper attempts to define the theory and practice of a modern approach to the initial workup of the patient with hypertension. The process includes a complete general medical evaluation along with special measures to enable the fullest characterization and clinical differentiation of the disease. The initial workup aims to (a) establish that the hypertension is sustained and should be treated; (b) identify all definable and curable causes for the hypertension; (c) identify the presence and degree of attendant risk factors such as smoking, alcohol use, obesity, diabetes, and abnormal lipid metabolism; (d) characterize the hypertension in terms of its pathophysiology; and (e) assess the presence and degree of target organ damage to the heart, brain, and kidneys. Because all diastolic hypertension is due to arteriolar vasoconstriction, a fundamental strategy of this process is to distinguish between renin-mediated and sodium-related vasoconstrictive forces and to evaluate which is preponderant. The chief instruments of this strategy are the renin-sodium profile and the response of plasma renin activity and blood pressure to specific antirenin system drugs. The captopril test, an important protocol in making this distinction, is primarily a powerful screening tool for confirming the possible presence or absence of curable renovascular disease or curable primary aldosteronism. That renin profiling cannot accurately discriminate between the contributions of either the renin or sodium-volume factors in that large fraction of medium-renin patients is not a viable reason for not performing the test. The test has its greatest strength for identifying sizable numbers of otherwise unrecognizable patients with very high or very low renin concentrations who might have curable disorders and who likely reflect different pathophysiologic vasoconstrictive mechanisms for which entirely different drug therapies are appropriate. However, the baseline renin test is also useful for assessing prognosis and the likelihood of a heart attack and it is valuable for deciding whether to use an anti-renin system drug (for medium and high renin concentrations) as opposed to natriuretic agents (low-renin patients) such as a diuretic or calcium antagonists as the primary step. In our present state of knowledge, the basic diagnostic biochemical workup includes the renin-sodium profile and the 24-h urinary sodium, potassium, and microalbumin excretion rates. This package is further enriched by baseline electrocardiography and echocardiography and the evaluation of glucose and lipid patterns.(ABSTRACT TRUNCATED AT 400 WORDS)
Heterogeneity among hypertensive subjects: a tool for clinical decision-making
Authors: Alderman M H 
Published: January 2020

Abstract
Current antihypertensive treatment strategy tends to approach all patients similarly, with decision to treat, the goal of treatment, and medication use based largely on blood pressure measurement. Clearly, it would make far more sense if a management strategy could be developed that was not solely dependent on measurement of blood pressure, but rather reflected a clearer understanding of individual likelihood of adverse outcome, the nature of blood pressure control, and the importance of associated clinical and biological characteristics. New tools make it possible to accurately assess the status of the heart, kidney, and blood vessels, both as a guide to the need for therapy and as a measure of treatment progress when the treatment is used. New understanding of the vasoconstrictor and volume contributions to blood pressure control coupled with a rich armamentarium of therapeutic agents make it possible to tailor therapy more appropriately. Finally, growing awareness of the contribution of concomitant risk factors has made it clear that overall success depends on attention to the whole patient.
Improved amplification of cytomegalovirus DNA from urine after purification of DNA with glass beads
Authors: Buffone G J , Demmler G J , Schimbor C M , Greer J 
Published: January 2020

Abstract
Cytomegalovirus can be detected in a variety of specimens including leukocytes, urine, saliva, feces, and various tissues by polymerase chain reaction (PCR) amplification of viral DNA. Although methods for amplification are fairly standard, sample preparation is not well characterized, especially for tissue. Typically, preparation of samples for PCR amplification ranges from simple boiling to phenol/chloroform extraction and quantification before testing. Several reports have described inhibition of the PCR in some samples types. Here we show that reliable detection of cytomegalovirus DNA in urine is obtained only after some degree of DNA purification, presumably because of PCR inhibition by a yet unidentified component present in a few of the urine samples tested. Glass, in the form of fine beads, was used to adsorb DNA such that protein and other substances could be selectively eluted before the recovery of DNA for PCR amplification. Urine samples prepared by this method did not show inhibition, and results correlated well with those by tissue culture for detection of cytomegalovirus.
Multianalyte microspot immunoassay--microanalytical "compact disk" of the future
Authors: Ekins R P , Chu F W 
Published: January 2020

Abstract
Throughout the 1970s, controversy centered both on immunoassay "sensitivity" per se and on the relative sensitivities of labeled antibody (Ab) and labeled analyte methods. Our theoretical studies revealed that RIA sensitivities could be surpassed only by the use of very high-specificity nonisotopic labels in "noncompetitive" designs, preferably with monoclonal antibodies. The time-resolved fluorescence methodology known as DELFIA--developed in collaboration with LKB/Wallac--represented the first commercial "ultrasensitive" nonisotopic technique based on these theoretical insights, the same concepts being subsequently adopted in comparable methodologies relying on the use of chemiluminescent and enzyme labels. However, high-specific-activity labels also permit the development of "multianalyte" immunoassay systems combining ultrasensitivity with the simultaneous measurement of tens, hundreds, or thousands of analytes in a small biological sample. This possibility relies on simple, albeit hitherto-unexploited, physicochemical concepts. The first is that all immunoassays rely on the measurement of Ab occupancy by analyte. The second is that, provided the Ab concentration used is "vanishingly small," fractional Ab occupancy is independent of both Ab concentration and sample volume. This leads to the notion of "ratiometric" immunoassay, involving measurement of the ratio of signals (e.g., fluorescent signals) emitted by two labeled Abs, the first (a "sensor" Ab) deposited as a microspot on a solid support, the second (a "developing" Ab) directed against either occupied or unoccupied binding sites of the sensor Ab. Our preliminary studies of this approach have relied on a dual-channel scanning-laser confocal microscope, permitting microspots of area 100 microns 2 or less to be analyzed, and implying that an array of 10(6) Ab-containing microspots, each directed against a different analyte, could, in principle, be accommodated on an area of 1 cm2. Although measurement of such analyte numbers is unlikely ever to be required, the ability to analyze biological fluids for a wide spectrum of analystes is likely to transform immunodiagnostics in the next decade.
Albuminuria and Diabetic Nephropathy: an Evolving Story
Authors: Watts Nelson B 
Published: January 2020

Abstract
The lifetime risk of diabetic nephropathy is ˜45% for patients with Type I (insulin-dependent) diabetes (1) and at least 30-35% for patients with Type II (non-insulin-dependent) diabetes (2, 3). In Type I diabetes, the incidence of readily detectable nephropathy rises steeply 10 years after the onset of diabetes (1). The progression from the appearance of “clinical proteinuria” (a positive test for protein upon routine urinalysis) to end-stage renal failure requiring dialysis or kidney transplantation occurs over about five years. This progression is usually relentless (4), but the rate of deterioration may be slowed or stabilized with improved glucose control (5-7), by the use of angiotensin-converting enzyme inhibitors (8, 9), diltiazem (10) [but not nifedipine (11)], and dietary protein restriction (12). Early intervention, before the development of clinical proteinuria, appears to be much more effective than later treatment.
Free thyroxin measured in dried blood spots from normal, low-birth-weight, and hypothyroid neonates
Authors: Lemonnier Françoise , Masson Joëlle , Laroche Dominique , Travert Josette , Travert Georges 
Published: January 2020

Abstract
We have adapted a new radioimmunoassay for free thyroxin (FT4) measurement in dried blood spots for use in neonatal screening for hypothyroidism. The method is easy, fast, and cheap. Within-assay and between-assay CVs are respectively 9.6% and 13.2%. In 997 neonates three days postpartum with normal thyrotropin concentrations, the mean FT4 concentration was 27.2 pmol/L (SD 7.3 pmol/L). There was no significant difference in mean FT4 concentration between boys and girls. FT4 concentrations increased linearly with birth weight or with gestational age, as expressed by multiple linear regression: FT4 (pmol/L) = 0.0016 birth weight (g) + 0.6931 gestational age (weeks) − 4.8772. Only gestational age significantly affected the FT4 value. For five hypothyroid infants tested on day three postpartum, FT4 values were all below the 1st percentile of values from healthy neonates. Thus, when the neonatal concentration of thyrotropin is above normal, FT4 measured in the same sample can provide a reliable earlier diagnosis of hypothyroidism.
Frequencies of Immunoglobulin Classes Involved in Monoclonal Gammopathies in Guadeloupe
Authors: Pileire Bernard , Bangou Jacqueline 
Published: January 2020

Abstract
The distribution of immunoglobulin classes in 213 monoclonal gammopathies from a West Indian population was studied over a five-year period at the CHRU of Pointe-a-Pitre, Guadeloupe. Monoclonal gammopathies were detected by routine electrophoresis on cellulose acetate (Sebia, France). Immunoglobulin antisera were used according to a laser immunonephelometric method (Behring, France).
Accuracy, precision, and interferences of three modified EMIT procedures for determining serum phenobarbital, urine morphine, and urine cocaine metabolite with a Cobas-Fara
Authors: Ammann Hélène , Vinet Bernard 
Published: January 2020

Abstract
Sung and Neely‘s proposed cost-reductive EMITTM (Syva Co., Palo Alto, CA) procedure allowed a 20-fold increase in the number of tests that can be performed with a single EMIT kit (1). They extensively diluted both EMIT reagents and supplemented the reaction medium with more substrate (glucose 6-phosphate, G6P) and cofactor (NAD+) to saturate the enzyme activity. This principle has been successfully applied to the determination of serum theophylline (1), serum anticonvulsanta (2), urineopiates (3), and urine benzoylecgonine, a cocaine metabolite (4).
Stability of phencyclidine and Amphetamines in Urine Specimens
Authors: Hughes R , Hughes A , Levine B , Smith M L 
Published: January 2020

Abstract
Knowledge about the stability of drugs in biological specimens can be critical to the proper interpretation of results. Stability of drugs of abuse in biological specimens has been recently reviewed (1). Two drugs for which limited stability data have been published are phencyclidine (PCP) and amphetamine (AMP)/methamphetamine (MA). Therefore, we undertook a stability study of these drugs in urine specimens. Urine samples from five drug-free individuals were fortified with PCP, AMP, and MA at three concentrations. These specimens were divided into aliquots; one was stored at room temperature (25 °C), the other in the refrigerator (4 °C). Over a six-month period, aliquots of each specimen were quantified by gas chromatography-mass spectrometry (2). A known control was analyzed with each batch; results were within 10% of the expected value.
Urinary Excretion of Free Toluenediamines in a Patient with Polyurethane-Covered Breast Implants
Authors: Chan Slu C , Birdsell Dale C , Gradeen Claire Y 
Published: January 2020

Abstract
We report the detection of free 2,4-toluenediamine in urine of a patient implanted with polyurethane-covered breast implants. Samples were collected on several dates, ranging from 21 days to seven months after the insertion of the implants, and these samples all showed the presence of free 2,4-toluenediamine at a concentration of about 1 μg/L. The chemical was not found in a urine sample collected before implantation. This finding is important for risk assessment of cancer in patients with this type of breast implant because the chemical is a suspected carcinogen. Free 2,6-toluenediamine, an isomer, was also found in all samples from this patient.
Interference in assay of free triiodothyronine by triiodothyronine-binding antibodies
Authors: Tokmakjian Sonya D , Haines D S Milton , Edmonds Merril W 
Published: January 2020

Abstract
A 39-year-old woman with a 20-year history of hypothyroidism caused by Hashimoto thyroiditis had been managed adequately with oral thyroxun (T4), 200 mg/day, until a few months before referral, at which time she developed symptoms of hyperthyroidism. Her thyroid hormone proffle at the time of referral is shown in Table 1 (Sample 1). Her normal value for serum thyrotropin (TSH) concentration indicates that she was euthyreid but, because of the high serum triiodothyronune (T3) value, the daily oral doseof T4 was decreased to 100 mg. The serum thyroid tests were repeated four weeks later (Table 1, Sample 2): The decreased T4 and increased TSH show that the patient had become hypothyroid at this dosagé of T4 but the serum T3 concentration was still in the high normal range.
Increased Estradiol Concentration of Unknown Origin
Authors: Vasiliades John , Hilgers T , Gentrup B , Remsburg J 
Published: January 2020

Abstract
We report an interesting case of above-normal serum estradiol concentration of unknown origin. A 30-year-old white woman was seen for infertility problems. Hormonal evaluation revealed the following results. Postovulatory progesterone concentrations and profile (a plot of hormone concentration vs time of cycle) were within the normal range for our laboratory (Table 1). However, the post-ovulatory estradiol concentrations were extremely high, although the curve appeared normal in profile (Table 1).
Heterozygous hypobetalipoproteinemia with fasting chylomicronemia
Authors: Huet G , Dieu M C , Martin A , Grard G , Bard J M , Fossati P , Degand P 
Published: January 2020

Abstract
We describe a disorder in which low-density lipoprotein (LDL)-cholesterol and apolipoprotein B are in low concentration (0.47 mmol/L and 0.28 g/L, respectively) and chylomicrons are still present in plasma after an 18-h fast. The d less than 1.006 fraction was isolated by flotation ultracentrifugation and the apolipoproteins were analyzed by electrophoresis, immunoblotting with anti-apolipoprotein B-100 antiserum, and isoelectric focusing. In the d less than 1.006 fraction of the fasting serum, we found an apolipoprotein B form with the same apparent molecular mass as apolipoprotein B-48 and similar in amount to apolipoprotein B-100 (respective percentages, 46% and 54%). The monosialylated form of the apolipoprotein C-III was severely decreased. After an oral fat load, the repartition of the two species of apolipoprotein B did not change greatly (respective percentages, 60% and 40%), and the concentration of serum triglyceride increased only from 1.20 to 1.65 mmol/L.
Approaches to minimizing interference by cross-reacting molecules in immunoassays
Authors: Miller James J , Valdes Roland 
Published: January 2020

Abstract
Here we review techniques useful in eliminating or reducing interferences caused by molecules that cross-react in immunoassays. The biochemical rationale for using these techniques is discussed. Examples are taken from recent studies aimed at reducing interferences caused by endogenous molecules such as digoxin-like immunoreactive factors or steroid hormones. In this context the role of protein-binding of cross-reacting molecules is also considered. Immunoassay ligand selectivity can be inherently limited by the heterogeneity of the antigenic response or by the structural similarity of epitopes on multiple ligands. Certain empirical approaches have proved useful in maximizing the analytical specificity of immunoassays. These approaches include isolating the relevant ligands before immunoassay, adjusting the kinetic or equilibrium conditions used during the assays, and developing more specific antisera. The physicochemical properties of the cross-reacting molecule best dictate which technique(s) to use. The approaches discussed here are general and apply to minimizing interference caused by a wide variety of both endogenous and exogenous cross-reacting molecules.
Accumulation of quinolinic acid in uremic serum and its removal by hemodialysis
Authors: Niwa Toshlmitsu , Yoshizumi Hldeo , Emoto Yutaka , Miyazaki Takashl , Hashimoto Naosuml , Takeda Naohfto , Tatematsu Akira , Maeda Kenji 
Published: January 2020

Abstract
Quinolinic acid was first identified in uremic serum by use of gas chromatography/mass spectrometry. Quantification by selected ion monitoring revealed that the serum concentration of quinolinic acid was markedly increased in chronic hemodialysis patients, and that the acid could be removed by conventional hemodialysis. The serum concentration of quinolinic acid was weakly but significantly correlated with the serum uric acid concentration. Accumulation of quinolinic acid in uremic blood may be involved in the pathogenesis of anemia, suppressed immune system, and uremic encephalopathy.
Concentrations of salivary testosterone and plasma total, non-sex-hormone-binding globulin-bound, and free testosterone in normal and hirsute women during administration of dexamethasone/synthetic corticotropin
Authors: Swinkels L M J W , van Hoof H J C , Ross H A , Smals A G H , Benraad Th J 
Published: January 2020

Abstract
Preliminary data indicate that the concentration of circulating cortisol may affect the binding of testosterone to plasma proteins. This interdependency was evaluated by the assessment of plasma cortisol, salivary (ST) and plasma total testosterone (TT), testosterone not bound to sex-hormone-binding globulin (n-SHBGT), and free testosterone (FT) in normal and in hyperandrogenemic women during combined dexamethasone/synthetic corticotropin administration. The concentrations of TT, FT, and ST significantly increased (P less than 0.001) during this dynamic test both in the controls and in hirsute women. Remarkably, however, n-SHBGT remained virtually unchanged in normal women in the follicular phase, decreasing in the luteal phase, and decreasing even more markedly in the hirsute women. Both the normal and the hirsute women showed a statistically significant negative correlation between the percentage of n-SHBGT and plasma total cortisol (P less than 0.001). The apparent decrease of n-SHBGT was the result of displacement of T from corticosteroid-binding globulin (CBG) by the increase in cortisol after the infusion of synthetic corticotropin: the CBG-bound T was measured as n-SHBGT because CBG was not precipitated with 50% saturated ammonium sulfate. Our results indicate that ST or FT better represents the clinical status of androgenicity than does n-SHBGT, as assessed by ammonium sulfate precipitation, because n-SHBGT also depends on the concentration of cortisol.
Interlaboratory comparison of the measurement of albumin in urine
Authors: Mueller PatrIcIa W , MacNeil Mary LouIse , Smith S Jay , Miller Dayton T 
Published: January 2020

Abstract
Because of increased interest in the assay of albumin in urine and the sensitivity required to quantify concentrations associated with (a) increased risk of developing end-stage renal disease and cardiovascular disease among people with diabetes and (b) renal damage caused by exposure to nephrotoxic substances, we conducted a pilot study of the variation of these measurements within and among five laboratories that use various immunoassays. These assays included two different enzyme immunoassays, two different immunoturbidimetric assays, a fluorescent immunoassay, and a zone immunoelectrophoresis assay. The results indicate considerable variation both within and among laboratories for measurements at or near the normal range. Variability is equally attributable to the precision of individual immunoassays and to the variation of the mean values obtained by each laboratory. Individual laboratory CVs ranged from 5.8% to 18.2% for mid- and high-concentration samples treated with preservative and from 8.4% to 23.6% for mid- and high-concentration samples containing no preservative. The relative bias of individual laboratory means ranged from -56.4% to 20.5% for the two preserved materials and from -32.6% to 0.8% for the two materials containing no preservative. To reduce the chance of misdiagnosing the risk associated with above-normal albumin concentrations in urine, we need to address the problems contributing to imprecision and inaccuracy, particularly laboratory-to-laboratory variability.