Labmedicine最新文献

{"title":"Proteins and Albumin","authors":"R. Bertholf","doi":"10.1309/LMKRNRGW5J03APZQ","DOIUrl":"https://doi.org/10.1309/LMKRNRGW5J03APZQ","url":null,"abstract":"Proteins are large polymers of amino acids linked by peptide bonds (Figure 1). The amino acid subunits of proteins are organic molecules that include a carboxylic acid linked through a carbon atom to a primary (or secondary, in proline) amine with the chemical formula H 2 N-CHR-COOH, in which R is a side group that largely determines the chemical properties of the amino acid. The simplest amino acid is glycine, H 2 N-CH 2 -COOH, in which the R side group is a hydrogen atom. Although this chemical template can be modified into an infinite array of molecules based on variations in the R group, only approximately 20 amino acids occur in proteins. The R groups confer acidic, alkaline, polar, or nonpolar properties to the various amino acids.","PeriodicalId":54328,"journal":{"name":"Labmedicine","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90511001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ABO/Rh Testing, Antibody Screening, and Biometric Technology as Tools to Combat Insurance Fraud: An Example and Discussion","authors":"Eleanor K Jator, Kimily Hughley","doi":"10.1309/LMIEC52ZF7RLLURK","DOIUrl":"https://doi.org/10.1309/LMIEC52ZF7RLLURK","url":null,"abstract":"In 2012, more than 47 million Americans lacked health insurance1; this is a serious problem because everyone will need access to healthcare at certain times in their lives. The main reason for lack of health insurance before the passing of the Patient Protection and Affordable Care Act (PPACA) in the United States has been reported to be affordability.1 In March 2010, the Patient Protection and Affordable Care Act was signed into law. The PPACA was especially enacted to reduce the number of uninsured Americans by providing affordable, quality health insurance and to curb healthcare spending.2 Reducing the number of uninsured is to be accomplished by expanding public (Medicaid) and private insurance as well as making health insurance more affordable by providing subsidies to eligible applicants, instituting mandates, providing tax credits and insurance exchanges.2 The Medicaid expansion clause is optional for states and as a result, some states choose not to expand eligibility. The PPACA law has a provision for a health insurance market place, which has allowed uninsured individuals, along with those who purchased their own insurance to compare and buy health insurance at affordable premiums with the help of subsidies.3 The law calls for insurance companies to accept all applicants regardless of any pre-existing conditions or gender and eliminates annual or lifetime caps on healthcare benefits. In addition, Members’ coverage cannot be terminated due to illness. All these provisions allow for addition as well as retention of individuals with health insurance coverage.2 Individuals living in states that have expanded Medicaid eligibility and have incomes below the poverty level are more likely to obtain health insurance coverage through Medicaid.3\u0000\u0000Even with the relative affordability of health insurance, some individuals will not still purchase health insurance for various reasons. States that do not …","PeriodicalId":54328,"journal":{"name":"Labmedicine","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91203381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Winifred Mayer Ashby (1879–1975): Medical Laboratory Scientist Extraordinaire","authors":"W. Monaghan","doi":"10.1309/LMS2V00FLEPQMABG","DOIUrl":"https://doi.org/10.1309/LMS2V00FLEPQMABG","url":null,"abstract":"Winifred Mayer Ashby was born in London, England in 1879. She later relocated with her family to the United States in Chicago, Illinois and became a citizen when she was 14 years old. She studied at Northwestern University and the University of Chicago; at the latter institution, she attained a Bachelor of Science degree in 1903. She then earned a Master of Science degree from Washington University in 1905. Next, she relocated to the Philippines, where she taught in schools and studied malnutrition. When she returned to the United States, she worked for a few years teaching chemistry and science in high schools; also, she worked in several clinical and medical laboratories. In 1917, while working at the Mayo Clinic in Rochester, Minnesota, she won a fellowship training award in pathology and immunology. At the Mayo Clinic, she began her seminal work on survival measurements of red blood corpuscles in healthy individuals and in patients with a variety of diseases. During that time she also performed studies on compatibility assessments and the transfusion of human blood. Blood groups had recently been elucidated and were initially named using Roman numerals: I (A), II (B), III (AB), and IV (O). Because of these antigenic differences, she was able to transfuse compatible group-O blood to patients of other types and then agglutinate out the inherited blood type by in vitro techniques. She then painstakingly diluted and counted the remaining cells …","PeriodicalId":54328,"journal":{"name":"Labmedicine","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72959474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overview of Urea and Creatinine","authors":"Jose H. Salazar","doi":"10.1309/LM920SBNZPJRJGUT","DOIUrl":"https://doi.org/10.1309/LM920SBNZPJRJGUT","url":null,"abstract":"Urea, commonly referred to as blood urea nitrogen (BUN) when measured in the blood, is a product of protein metabolism. BUN is considered a non-protein nitrogenous (NPN) waste product. Amino acids derived from the breakdown of protein are deaminated to produce ammonia. Ammonia is then converted to urea via liver enzymes. Therefore, the concentration of urea is dependent on protein intake, the body’s capacity to catabolize protein, and adequate excretion of urea by the renal system. 1 Urea accounts for the majority (up to 80%-90%) of the NPNs excreted by the body. The body’s dependency on the renal system to excrete urea makes it a useful analyte to evaluate renal function. An increase in BUN can be the result of a diet that is high in protein content or decreased renal excretion.","PeriodicalId":54328,"journal":{"name":"Labmedicine","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89237534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Calcium, Magnesium, and Phosphate","authors":"Lindsay A. L. Bazydlo, M. A. Needham, N. Harris","doi":"10.1309/LMGLMZ8CIYMFNOGX","DOIUrl":"https://doi.org/10.1309/LMGLMZ8CIYMFNOGX","url":null,"abstract":"### Calcium\u0000\u0000#### Overview of Analyte\u0000\u0000Calcium plays significant roles in cell structural components and biochemical functioning through signaling within and external to the cell. Calcium is essential for normal neuromuscular function and for correct functioning of the coagulation factors. It is the most prevalent cation in the body and is found in the skeleton, soft tissue, and extracellular fluid. In serum, the total calcium concentration is approximately 8.4 to 10.2 mg/dL (2.1–2.6 mmol/L). This calcium exists in 2 different forms, namely, bound and free. The protein-bound form of calcium accounts for approximately 40% of total serum calcium, of which 80% is bound to albumin and the remaining 20% is bound to globulins.1 A total of 10% of the total calcium is bound to small anions, including bicarbonate, phosphate, citrate, and lactate.1 The free, physiologically active calcium (often called ionized calcium) concentration in the plasma is approximately 4.4 to 5.2 mg/dL (1.1 to 1.3 mmol/L). The intracellular cytoplasmic calcium concentration is typically very low in unstimulated cells—approximately 0.1 μM. This is 4 orders of magnitude lower than the serum free-calcium concentration. The cellular machinery is exquisitely responsive to very small elevations in cytoplasmic calcium, making it a highly sensitive second messenger.\u0000\u0000The amount of serum calcium that is bound to plasma protein can be impacted by a number of factors, one of which is the pH of blood. In a patient with alkalosis, the higher pH allows for greater binding of free calcium to proteins, effectively decreasing the concentration of free calcium. Ionized calcium will decrease 0.16 mg/dL (0.04 mmol/L) with every 0.1-unit increase in pH in patients with acute respiratory alkalosis.2 \u0000\u0000Scientists have developed various empirical formulae to adjust the total serum calcium measurement according to the serum protein concentration. This method is used to exclude protein effects when interpreting total calcium … \u0000\u0000[↵][1]* To whom correspondence should be addressed. E-mail: lbazydlo{at}ufl.edu\u0000\u0000 [1]: #xref-corresp-1-1","PeriodicalId":54328,"journal":{"name":"Labmedicine","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87353844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Glucose and Hemoglobin A1c","authors":"Vicki Freeman","doi":"10.1309/LMNSU432YJWCWZKX","DOIUrl":"https://doi.org/10.1309/LMNSU432YJWCWZKX","url":null,"abstract":"Glucose, a monosaccharide, is the primary source of energy for the human body. It is used by the liver and other cells for energy or stored as glycogen for later use. The level of glucose in the bloodstream is regulated by 2 pancreatic hormones, insulin and glucagon. Insulin is released when glucose levels rise. Insulin acts by increasing glycogenesis, lipogenesis, and glycolysis, causing a decrease of glucose in the bloodstream. Glucagon is released when glucose levels fall, causing the liver to release stored glucose (glycogen) into the bloodstream (glycogenolysis), thereby increasing the level of glucose in the bloodstream.\u0000\u0000Hemoglobin A1c (HbA1c), also called glycosylated hemoglobin, is a hemoglobin compound produced when glucose reacts with the amino group on a hemoglobin molecule forming a ketoamine. The glucose molecule is attached to one or both N-terminal valines of the β-polypeptide chains of normal adult hemoglobin.1 The HbA1c formation is proportional to the blood glucose concentrations. Because the average red blood cell life is approximately 120 days, the glycosylated hemoglobin level reflects the average blood glucose level during the previous 2 to 3 months.\u0000\u0000Glucose testing is used to determine if an individual has hyperglycemia or hypoglycemia. A high fasting glucose level (≥126 mg/dL) and/or a high HbA1c level (>6.5%) might indicate that an individual has diabetes mellitus.\u0000\u0000HbA1c is a reliable method of monitoring long-term diabetes mellitus control; it determines the average blood glucose level of an individual during a period of approximately 3 months. Normal values range from 4.0% to 6.0%. Results of a study2 have shown the strong linear relationship between average blood glucose levels and HbA1c levels. Current American Diabetes mellitus Association guidelines recommend that a HbA1c test be performed at least twice yearly on patients who are meeting treatment … \u0000\u0000[↵][1]* To whom correspondence should be addressed. E-mail: vfreeman{at}utmb.edu\u0000\u0000 [1]: #xref-corresp-1-1","PeriodicalId":54328,"journal":{"name":"Labmedicine","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2014-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78386122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quick Guide to Endocrinology","authors":"L. Witherspoon","doi":"10.1309/LM3UKUX08VZABBRZ","DOIUrl":"https://doi.org/10.1309/LM3UKUX08VZABBRZ","url":null,"abstract":"Written by William E. Winter, MD, DABCC, FCAP, FACB, Lindsay A. L. Bazydlo, PhD, DABCC, and Neil S. Harris, MD, DABCC, FACP, FACB 189 pages. Washington, DC: American Association for Clinical Chemistry Press, 2013. $28 (non-members), $25 (members). ISBN-13: 9781594251573\u0000\u0000The Quick Guide to Endocrinology , a new entry in the Quick Guide series published by the American Association for Clinical Chemistry (AACC), tackles the task of rendering a complex subject understandable and approachable in a fraction of the space that standard endocrinology textbooks require. In this endeavor, Dr Winter and his coauthors have largely succeeded.\u0000\u0000\u0000\u0000The Quick Guide begins with a brief introduction to hormones, providing context for the ensuing chapters focused on …","PeriodicalId":54328,"journal":{"name":"Labmedicine","volume":"88 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90331203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clinical Utility of the Time-to-Positivity/ Procalcitonin Ratio to Predict Bloodstream Infection Due to Coagulase-Negative Staphylococci","authors":"B. Lu, Li Shi, Fengxia Zhu, Huan Zhao","doi":"10.1309/LM6Y0IALOGL4KAEC","DOIUrl":"https://doi.org/10.1309/LM6Y0IALOGL4KAEC","url":null,"abstract":"Objective: To develop a novel clinical diagnostic method to distinguish bacteremia from blood contamination due to coagulase-negative staphylococci (CNS) by using the ratio of the time to positivity (TTP) of a blood culture with positive results to its serum procalcitonin (PCT) level. Methods: We retrospectively reviewed the clinical and microbiological records of 102 patients who had 1 or more blood cultures that tested positive for CNS from August 2007 through February 2012. Results: Receiver operating characteristic (ROC) curve analysis indicated that, at a cutoff of 1.24 ng per mL, 21.5 hours, and 22.5 (hours × mL)/ng,the TTP to PCT ratio, PCT level, and TTP yielded the most favorable discrimination for bacteremia caused by CNS, with sensitivities of 85.7%, 78.6%, and 61.9%,respectively, and specificities of 80.0%, 78.3%, and 61.7%,respectively. The TTP to PCT ratio was the most accurate of the studied variables in predicting CNS-triggered bacteremia levels. Conclusion: The TTP to PCT ratio is a useful predictor to differentiate the culture samples that test positive, revealing the presence of CNS bacteremia, from those that are merely contaminated.","PeriodicalId":54328,"journal":{"name":"Labmedicine","volume":"18 1","pages":"313-318"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83311302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A 1-Day-Old Neonate Presents With an Unexpected Antibody","authors":"Charles T Beavers, M. Ayyoubi","doi":"10.1309/LMWJ5TNUSQBWELGA","DOIUrl":"https://doi.org/10.1309/LMWJ5TNUSQBWELGA","url":null,"abstract":"Patient: 1-day-old Caucasian male neonate.\u0000\u0000History of Present Illness: The neonate was born to a 26-year-old gravida 1 female at 37 weeks gestational age via Caesarean section, secondary to failure to progress in labor. The infant was delivered without complications. Routine blood work on the infant revealed an unexpected red cell antibody. A direct antiglobulin test (DAT) and antibody screen were both noted to be positive.\u0000\u0000Past Medical History: The mother received routine prenatal care throughout her pregnancy. She has a past medical history of chronic hypertension, an anti-E antibody, a pan-reactive autoantibody to red cell antigens, and mild intermittent asthma. The anti-E was discovered upon prenatal screening in the mother, but was not identified in subsequent auto-absorbed specimens. No previous transfusions were documented.\u0000\u0000Social History: Non-contributory.\u0000\u0000Family History: Non-contributory.\u0000\u0000Physical Exam: The neonate’s APGAR scores were 8 at 1 minute and 9 at 5 minutes. An exam showed the neonate to be in no acute distress and with essentially normal physical findings.\u0000\u0000Principal Laboratory Findings: See Table 1, Table 2, Table 3, and Table 4.\u0000\u00001. What are the mother’s most striking laboratory findings?\u0000\u00002. The mother and neonate share the same antibody identification panel in Tables 3 and 4. Why?\u0000\u00003. What autoimmune conditions of pregnant women have been observed to produce transplacental antibodies resulting in neonatal disease?\u0000\u00004. What additional workup is necessary …","PeriodicalId":54328,"journal":{"name":"Labmedicine","volume":"21 1","pages":"329-332"},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74695382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Unexpected Finding of Diphyllobothrium nihonkaiense in a Patient with Inflammatory Bowel Disease","authors":"Mawuli F. Attipoe, W. Putnam, C. Sturgis","doi":"10.1309/LM8LSPFGFY2UT2MD","DOIUrl":"https://doi.org/10.1309/LM8LSPFGFY2UT2MD","url":null,"abstract":"The patient in this case was a 52-year-old man with a known history of ulcerative colitis. His inflammatory bowel disease was asymptomatic; he presented for an outpatient endoscopy for routine surveillance of his condition. He underwent lower endoscopy to exclude colonic dysplasia; he was taking no medications at the time of his procedure. The patient had experienced no diarrhea or blood loss from the rectum and reported no symptoms that would suggest changes in his condition since his most recent previous colonoscopy 27 months previously. The patient had no known allergies. We did not discuss with the patient whether he might have ingested raw or undercooked fish. Results of a digital rectal examination were normal.\u0000\u0000### Endoscopic Findings\u0000\u0000On lower endoscopic examination, we discovered mild inflammation characterized by friability, granularity, linear erosions, and loss of vascularity in a continuous and circumferential pattern from the anus through the rectum.\u0000\u0000Compared with the results of previous examinations, the findings were unchanged and were believed by the gastroenterologist to be consistent with the patient’s known ulcerative colitis. A benign-appearing sessile polyp was also noted in the rectum; this entity was biopsied and sent to the pathology department. The remainder of the colon and the terminal ileum had an unremarkable appearance. An incidental parasitic tapeworm was discovered in the ascending colon (Image 1). The tapeworm was extracted from the ascending …","PeriodicalId":54328,"journal":{"name":"Labmedicine","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2013-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90499406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}