PubMed Health⌕ Search

Biomedical subjects

M D Engelmann

Publications and source records attributed to M D Engelmann.

14 recordsLinked to original sources
PubMed2003

Solid-phase micro extraction (SPME) and headspace derivatization of clenbuterol followed by GC-FID and GC-SIMMS quantification.

Solid-phase micro extraction (SPME) and on-fiber derivatization followed by Gas Chromatography coupled with Flame Ionization Detection (GC-FID) or Selected Ion Monitoring Mass Spectrometry (GC-SIMMS) allows for simple yet sensitive quantification for the hexamethyldisilazane derivative of the beta-agonist clenbuterol. Using an 85- micro m polyacrylate fiber, the analysis method is optimized with respect to extraction time, derivatization time and temperature, and solution pH. In addition, the use of a rapid temperature ramping injection port allows for optimization of fiber desorption conditions. Under optimal conditions, the limits of detection for the hexamethyldisilazane derivative of clenbuterol are 1.1 ppb by FID and 0.20 ppb by SIMMS.

Adrenergic beta-Agonists↗
PubMed2001

The complete dechlorination of DDT by magnesium/palladium bimetallic particles.

The complete dechlorination of 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane (DDT) by a magnesium/palladium bimetallic system has been accomplished. The reaction takes place under ambient temperature and pressure and mild reaction conditions requiring only 0.25 g of magnesium and 0.3% palladium (wt/wt) to drive the dechlorination of 100 microg DDT (50 ppm in 2 ml). The process is both rapid and complete requiring less than 10 min to attain total dechlorination within the detection limit (approximately 10 pg for DDT) of electron capture detection gas chromatography (GC-ECD). The major product formed, as deduced from mass spectrometry (GC-MS) is the hydrocarbon skeleton, 1,1-diphenylethane. This technology may allow for the development of an economic and environmentally benign method of DDT remediation.

Chlorine↗
PubMed2000

[Early repolarization. Differential diagnosis of electrocardiographic ST segment elevation].

'Early repolarisation' (ER) represents a normal electrocardiographic variant with persistent ST segment elevation and is considered a benign condition. ER is found in approximately 1-2% of the population and thus it is common among patients in emergency rooms and coronary care units. ER is not associated with increased mortality or morbidity. The electrocardiographic characteristics of ER include widespread ST segment elevation, upward concavity of the initial portion of the ST segment, notching of the terminal QRS complex, and concordant T waves of large amplitude. The most important differential diagnoses to ER are pericarditis and acute myocardial infarction, AMI. Only through a systematic evaluation in the acute setting are patients with AMI assured the relevant revascularisation therapy. Furthermore patients with ER and without cardiac disease can avoid unnecessary and potentially harmful procedures such as fibrinolysis and coronary angiography.

Diagnosis, Differential↗
PubMed2000

[Early repolarization. ST-segment elevation as a normal electrocardiographic variant].

'Early repolarisation' (ER) represents a normal electrocardiographic variant with persistent ST segment elevation and is considered a benign condition. ER is found in approximately 1% of the population and in up to 13% of patients presenting with chest pain in the emergency room. This case report presents a 49 year-old man with ER suspected of acute myocardial infarction due to the combination of chest pain and electrocardiographic ST segment elevation. [figure: see text] The case report describes the electrocardiographic characteristics associated with the syndrome ER and the problems in distinguishing ER from other ST segment elevation syndromes.

Chest Pain↗
PubMed2000

[Association or agreement between clinical measurement methods?].

Method comparison is often needed and unfortunately often analysed inappropriately. In particular, the use of correlation may be misleading with a high value of the correlation coefficient interpreted as an indication of good agreement. The difference between association and agreement are emphasized and the difference plot method is demonstrated using a worked example. Finally the interpretation of bias and limits of agreement are discussed.

Blood Chemical Analysis↗
PubMed1999

Breast-feeding influences thymic size in late infancy.

We have previously shown that breast-fed infants have a considerably larger thymus at 4 months than formula-fed infants. The aim of the present study was to investigate whether breast-feeding also influences the thymic size in late infancy. In a cohort of 50 infants, all being partially breast-fed when recruited at 8 months, ultrasound assessment of the thymic index (a volume estimate) was performed at both 8 and 10 months of age. At 10 months the thymic index was significantly higher in those still being breast-fed compared to infants who had stopped breast-feeding between 8 and 10 months of age (P=0.05). This difference became more significant when controlled for the influence of infectious diseases (P=0.03). In infants still breast-fed at 10 months there was a significant correlation between the number of breast-feeds per day and their thymic index (P=0.01). Conclusion The effect of breast-feeding on thymus size is likely to be caused by immune modulating factors in breast milk. Breast milk influences thymic size in late infancy.

Breast Feeding↗
PubMed1998

[Iron deficiency during the first year of age].

Iron deficiency is the most common nutritional deficiency in late infancy. In healthy term infants iron stores are depleted at the age of four to six months and the infant becomes increasingly dependent on exogenous sources of iron. Furthermore, the iron content and bioavailability in a traditional weaning diet are low. The consequences of iron deficiency in late infancy span from pallor to risk of impaired psychomotor development. Approaches to prevent iron deficiency and problems associated with these approaches are reviewed, and general guidelines for a weaning diet as well as guidelines with special emphasis on preventing iron deficiency are given. The present article identifies infants at high risk of developing iron deficiency including: immigrants, infants from a deprived background, infants to whom cows' milk is introduced early and/or given in large quantities, and infants from families with unusual eating habits. Finally, the commonly employed clinical practice for treating iron deficiency is mentioned.

Anemia, Iron-Deficiency↗
PubMed1998

Meat intake and iron status in late infancy: an intervention study.

BACKGROUND: Highly bioavailable dietary iron is needed to ensure optimal iron status in infants during weaning. The purpose of the current study was to examine the effect of increased meat intake on hemoglobin concentration (Hb), serum ferritin (SF), and serum transferrin receptors (TfR) in late infancy. METHODS: Forty-one healthy, term, partially breast-fed 8-month-old infants were randomized into two groups: a low-meat group (LMG), in which infants received a diet with a mean meat content of 10 g/day and a high-meat group (HMG), in which infants received a diet with a mean meat content of 27 g/day. The intervention lasted for 2 months, and blood samples were drawn on the first and the last days of the intervention. RESULTS: At the beginning of the intervention, no significant differences were found in Hb, SF, TfR values between the two groups. After the intervention, there was a significant (p = 0.008) difference in the change in hemoglobin (delta Hb) concentration. In the LMG delta Hb was -4.9 g/l (range, -12.9-5.6 g/l) and in the HMG -0.6 g/l (range, -12.1-7.3 g/l). There was no significant difference in change in SF or TfR concentrations between the LMG and the HMG. The intake of iron from meat (mean; range) was significantly higher (p = 0.0001) in the HMG (0.4 mg/day; 0.02-0.7 mg/day) than in the LMG (0.1 mg/day; 0.03-0.5 mg/day). However, there was no significant difference in total iron intake between the HMG (3.1 mg/day; 0.4-6.2 mg/day) and the LMG (3.4 mg/day; 1.4-6.1 mg/day). CONCLUSION: The results suggest that an increase in meat intake can prevent a decrease in Hb in late infancy, probably by enhancing iron absorption. However, there was no effect on iron stores or on cellular iron deficiency, evaluated by SF and TfR levels, respectively.

Anthropometry↗
PubMed1998

The influence of meat on nonheme iron absorption in infants.

During weaning the infant has a high iron requirement, and highly available dietary iron is needed to ensure optimal iron status. Muscle tissue has been identified as an enhancer of nonheme iron absorption in adults, although the influence of meat on nonheme iron absorption in infants has not been previously reported. The effect of the addition of 25 g of meat (lean beef) on nonheme iron absorption from a home-prepared vegetable purée meal (80 g of vegetables) was investigated in infants in the present study. The meals did not differ in their contents of other known enhancers or inhibitors of nonheme iron absorption. Incorporation of stable isotopes of iron (57Fe and 58Fe) into red blood cells 14 d after intake was used to measure iron absorption, using a cross-over design in eight healthy infants 43-49 wk of age. Nonheme iron absorption was significantly increased (p = 0.002) from the vegetable purée with added meat (geometric mean 15.0%) compared with the puréed vegetables (geometric mean 9.9%). These results thus suggest that meat is also an enhancer of nonheme iron absorption in infants and that nonheme iron absorption from weaning foods can be increased by the addition of meat.

Adult↗
PubMed1997

Thymus size evaluated by sonography. A longitudinal study on infants during the first year of life.

OBJECTIVE: To use sonography in a follow-up study aimed at assessing the size of the thymus in healthy infants, and to search for a possible relation to clinical variables, breast-feeding status, and illness. MATERIAL AND METHODS: Forty-seven healthy infants were examined as neonates and re-examined at 4 months of age. Thirty-seven of the infants were also re-examined at 8, 10, and 12 months of age. The thymus size was measured with the sonographic thymic index used as a volume estimate. The correlations between the thymic index and the sex, weight, length, illness, and breast-feeding status of the infants were analysed. RESULTS: At birth the median thymic index was 12 (range 4-29). At 4 months the median thymic index was 28 (range 12-83). The thymic index was positively correlated to the body length of the infant and to its breast-feeding status (p < 0.0001). At 8 months the median thymic index was 29 (range 6-55) and most of the variation could be explained by the length of the infant (p = 0.0018, r = 0.50). At 10 months the median thymic value had decreased to 19 (range 9-49), and at 12 months to 17 (range 7-53). Infants exclusively breast-fed during the first 4 months of their lives had a larger thymic index at 10 months than formula-fed infants (p = 0.0024). Infants with fever episodes from 10 to 12 months had a smaller thymic index at 12 months (p = 0.0241). CONCLUSION: The thymus size in healthy infants increases from birth to 4 and 8 months of age and then decreases. Most of the individual variation can be explained by breast-feeding status and body size, and to a lesser extent by illness. We propose statistical models by which the normal variation/distribution of the thymic size can be estimated in infants up to one year of age.

Age Factors↗
PubMed1996

Decreased thymus size in formula-fed infants compared with breastfed infants.

The objective of this research was to investigate if breastfeeding affects the size of the thymus. Ultrasound assessment of the thymic index (a volume estimate) at birth and age 4 months in 47 healthy infants born in the hospital were used. History of feeding mode, body size and illness were registered. At 4 months the geometric mean thymic index (range) was 38.3 (16.2-83.2) in exclusively breastfed infants (n = 21), 27.3 (15.6-50.0) in partially breastfed infants (n = 13) and 18.3 (12.2-32.6) in formula fed infants (n = 13; p = 0.0001, ANOVA). This finding was independent of weight, length, sex and previous or current illness. There was no significant difference in mean thymic index at birth between the three feeding groups and mean thymic index had increased in all three groups from birth to 4 months. For the formula-fed infants it seems that the thymus remains large for a period and then decreases in size after breastfeeding has been terminated. We conclude that the thymus is considerably larger in breastfed than in formula-fed infants at the age of 4 months. The cause of this difference is unknown but human milk contains many immune modulating factors that might cause this effect.

Analysis of Variance↗
PubMed1995

[Fatal pancreatitis associated with valproate therapy].

We report a fatal case of haemorrhagic pancreatic necrosis in a 15-year-old mentally retarded epileptic male who had been taking sodium valproate (VPA) in the recommended dosage for one and a half years. The patient was admitted to hospital because of acute abdominal pain, with nausea and vomiting. Serum amylase was 609 U/l (normal range 100-360 U/l). Two exploratory laparotomies were performed. The second revealed haemorrhagic pancreatitis with areas of necrosis. VPA therapy was discontinued after the second laparotomy, but the patient died 25 days after admission. Autopsy showed extensive haemorrhagic pancreatic necrosis. Non-specific vomiting and abdominal pain occur frequently during VPA therapy, but VPA-related pancreatitis should be considered when there is severe abdominal pain with nausea and vomiting. Awareness of this problem and early discontinuation of VPA therapy may prevent serious reactions.

Acute Disease↗
PubMed1992

Drugs in the womb: college student perceptions of maternal v. fetal rights.

A survey of 523 college undergraduates regarding a pregnant woman's culpability for the use of specific drugs during pregnancy indicated that a rank order of the relative safety of the drugs existed in the minds of the respondents. Tobacco, alcohol and aspirin were perceived as similar in their consequences to the fetus, while cocaine was considered to be the most deleterious and Accutane, the least deleterious. Although 75 percent would imprison a pregnant woman who used cocaine, only 16 percent would do so for the use of Accutane, a prescription drug. The 87 percent of the students who believed that the fetus was a child, were more likely to consider the use of the five drugs during pregnancy as a form of child abuse and were also more willing to imprison the "offending" women. It was suggested that drug education programs need to place more emphasis on the potentially deleterious consequences of prescribed medicines to the fetus.

Adult↗