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PubMed2005

Winemaking biochemistry and microbiology: current knowledge and future trends.

The fermentation of grape must and the production of premium quality wines are a complex biochemical process that involves the interactions of enzymes from many different microbial species, but mainly yeasts and lactic acid bacteria. Yeasts are predominant in wine and carry out the alcoholic fermentation, while lactic acid bacteria are responsible for malolactic fermentation. Moreover, several optional winemaking techniques involve the use of technical enzyme preparations. Considerable progress has been made recently in understanding the biochemistry and interactions of enzymes during the winemaking process. In this study, some of these recent contributions in the biochemistry of winemaking are reviewed. This article intends to provide an updated overview (including works published until December, 2003) on the main biochemical and microbiological contributions of the different techniques that can be used in winemaking. As well as considering the transformations that take place in traditional winemaking, the production of special wines, such as sparkling wines, 'sur lie' wines, and biologically aged wines, are also studied.

Carbonated Beverages↗
PubMed2003

Biogenic amines and polyamines: similar biochemistry for different physiological missions and biomedical applications.

Biogenic amines are organic polycations derived from aromatic or cationic amino acids. All of them have one or more positive charges and a hydrophobic skeleton. Nature has evolved these molecules to play different physiological roles in mammals, but maintains similar patterns for their metabolic and intracellular handling. As deduced from this review, many questions still remain to be solved around their biochemistry and molecular biology, blocking our aims to control the relevant pathologies in which they are involved (cancer and immunological, neurological, and gastrointestinal diseases). Advances in this knowledge are dispersed among groups working on different biomedical areas. In these pages, we put together the most relevant information to remark how fruitful it can be to learn from Nature and to take advantage of the biochemical similarities (key protein structures and their regulation data on metabolic interplays and binding properties) to generate new hypothesis and develop different biomedical strategies based on biochemistry and molecular biology of these compounds.

Amine Oxidase (Copper-Containing)↗
PubMed2002

Screening for trisomy 21 by maternal age, fetal nuchal translucency and maternal serum biochemistry at 11-14 weeks: a German multicenter study.

OBJECTIVE: To examine the effectiveness of screening for trisomy 21 by a combination of maternal age, fetal nuchal translucency (NT) thickness and maternal serum biochemistry using free beta-human chorionic gonadotropin (hCG) and pregnancy-associated plasma protein-A (PAPP-A) at 11-14 weeks of gestation. METHODS: This was a multicenter study of screening for trisomy 21 by a combination of maternal age, fetal NT and maternal serum free beta-hCG and PAPP-A at 11-14 weeks of gestation, using the methodology developed by the Fetal Medicine Foundation. The distribution of estimated risks for trisomy 21 was determined and the sensitivity and false-positive rate for a risk cut-off of 1 in 300 were calculated. RESULTS: In total, 3864 singleton pregnancies with live fetuses at 11-14 weeks were examined and the fetal NT and maternal serum free beta-hCG and PAPP-A were successfully measured in all cases. The median maternal age was 33 (range 15-46) years and, in 1271 (35.8%), the age was 35 years or more, the median gestation at screening was 12 (11-14) weeks and the median fetal crown-rump length was 64 (range 45-84) mm. The fetal NT was above the 95th centile in 73.7% (14 of 19) of trisomy 21 and in 4.8% (169 of 3505) of normal pregnancies. The estimated risk for trisomy 21 based on maternal age, fetal NT and maternal serum free beta-hCG and PAPP-A was 1 in 300 or greater in 6.6% (233 of 3505) of normal pregnancies, in 84.2% (16 of 19) of those with trisomy 21 and 88.9% (24 of 27) of those with other chromosomal defects. CONCLUSIONS: In Germany, the results of screening for chromosomal defects by measurement of fetal NT and maternal serum biochemistry, in centers with appropriately qualified sonographers, are similar to those reported in the UK using the same methodology.

Adult↗
PubMed1996

Copper biochemistry and molecular biology.

In this review, our basic and most recent understanding of copper biochemistry and molecular biology for mammals (including humans) is described. Information is provided on the nutritional biochemistry of copper, including food sources, intestinal absorption, transport, tissue distribution, and excretion, along with descriptions of copper binding proteins and other factors involved and their roles in these processes. The metabolism of copper and its importance for the functions of a roster of vital enzymes is detailed. Its potential toxicology is also addressed. Alterations in copper metabolism associated with genetic and nongenetic diseases are summarized, including potential connections to inflammation, cancer, atherosclerosis, and anemia, and the effects of genetic copper deficiency (Menkes syndrome) and copper overload (Wilson disease). Understanding these diseases suggests new ways of viewing the normal functions of copper and provides new insights into the details of copper transport and distribution in mammals.

Amino Acid Sequence↗
PubMed1998

An exploratory investigation of the morphology and biochemistry of cellulite.

Dimpling of the skin of the thighs and buttocks is commonly referred to as cellulite, and it afflicts women much more frequently than men. Whereas many therapies that presume cellulite is caused by an abnormality of adipose tissue have gained recent popularity, the basic pathophysiology of cellulite has not been clearly identified. Theoretically, cellulite could reflect differences in adipose tissue biochemistry or connective tissue structure of affected versus unaffected individuals and/or of affected versus unaffected regions within an individual. We report here on direct experimental examination of these possibilities. Seven healthy adult subjects (five women, two men; four affected, three unaffected) underwent sonography of the thigh, measurement of regional in vivo subcutaneous adipose tissue metabolism (catecholaminergic responsiveness and blood flow) by microdialysis probe studies of the abdomen and the thigh, and full-thickness wedge biopsy of the thigh under local anesthesia. The presence of cellulite was defined as evidence of dimpling of the skin of the posterolateral thigh when the subject stood with the affected leg flexed to 90 degrees at the hip and knee. Any continuous area of skin at least 3 cm in diameter in which no dimpling was evident was designated as "unaffected." In all affected individuals, studies were performed to include both affected and unaffected areas of the thigh. In vitro pathologic examination of wedge biopsies and in vivo sonographic examination of the thigh both showed a diffuse pattern of extrusion of underlying adipose tissue into the reticular dermis in affected, but not unaffected, individuals. In vitro and in vivo studies also demonstrated that women had a diffuse pattern of irregular and discontinuous connective tissue immediately below the dermis, but this same layer of connective tissue was smooth and continuous in men. This connective tissue layer was more irregular and discontinuous in affected versus unaffected individuals. No significant differences were noted in subcutaneous adipose tissue morphology, lipolytic responsiveness, or regional blood flow between affected and unaffected sites within individuals. There is a sexual dimorphism in the structural characteristics of subdermal connective tissue that predisposes women to develop the irregular extrusion of adipose tissue into the dermis, which characterizes cellulite. These gender-related differences are diffuse and not localized only to affected areas. There is no evidence of any primary role for adipose tissue physiology, blood flow, or biochemistry in the etiology of cellulite, although the connective tissue of the female thigh is structured to accentuate differences in small subdermal adipose tissue depots.

Abdomen↗
PubMed1974

Effects of Cation Levels of the Nutrient Medium on the Biochemistry of Chlorella: II. Factorial Experiment.

A factorial experiment was designed to study the effects of Mg(2+), K(+), and Na(+) on the growth and biochemistry of Chlorella sorokiniana. Raising Mg(2+) or K(+) concentration in the nutrient medium increased growth rates as well as total N levels and Mg(2+) and K(+) accumulation by the cells. The total N effect was Mg(2+)-dependent-if Mg(2+) was below a certain level in the medium-increasing the K(+) concentration did not raise the total N level of cells. Low nutrient levels of K(+) decreased the levels of unsaturated fatty acids (especially 18:1 and 18:3), while increasing the levels of palmitic acid (16:0), total fatty acids, and total lipid. Increasing nutrient K(+) concentrations were accompanied by increases in levels of some unsaturated fatty acids, with a concomitant reduction in 16:0, total fatty acids and total lipid. Low Mg(2+) levels in the nutrient medium reduced the cellular levels of palmitic acid, total fatty acids, total lipid, and certain unsaturated fatty acids (though this last effect also depended on the nutrient level of K(+)). These relationships indicate that Mg(2+) may be important in the initial steps of fatty acid synthesis, whereas K(+) may be necessary for the formation of certain unsaturated fatty acids. Variations in Na(+) concentration did not have any significant effect on the growth and biochemistry of C. sorokiniana.

Journal Article↗
PubMed2005

Effects of HFE gene mutations and alcohol on iron status, liver biochemistry and morbidity.

BACKGROUND AND AIMS: The aims of the present study were to determine: (i) whether alcohol consumption is greater in individuals with HFE mutations; and (ii) whether common HFE mutations modify the effects of alcohol on serum iron and liver biochemistry or morbidity. METHODS: The residents of the town of Busselton in Western Australia were subject to cross-sectional health surveys between 1966 and 1983. In 1994/1995 all surviving participants of the earlier surveys were invited to take part in a follow-up survey. Logistic, linear and Poisson log-linear regression analyses were performed in 1490 men and 1452 women from the 1994/1995 survey to assess the relationships between HFE mutations, alcohol, iron levels, liver biochemistry and morbidity. RESULTS: Heavy or moderate alcohol consumption was present in 7% or 36% of men and 0.5% or 12% of women, respectively. Alcohol consumption strongly influenced levels of serum ferritin and gamma glutamyl transpeptidase (GGT) and mean cell volume (MCV) in men and women but only alanine aminotransferase (ALT) levels in women. These effects were independent of HFE gene mutations. Hospital admission rates for respiratory disorders were higher in men with the C282Y mutation. CONCLUSIONS: Alcohol consumption strongly influences serum ferritin and GGT levels and MCV in men and women but only ALT levels in women, and these effects are independent of HFE mutations. HFE gene mutations do not predispose to moderate or heavy alcohol consumption. The C282Y mutation is associated with increased respiratory admission rates in men.

Alanine Transaminase↗
PubMed1995

Positron emission tomography and plasma biochemistry findings in schizophrenic patients before and after electroconvulsive therapy.

The clinical effects of electroconvulsive therapy (ECT) on the morbidity of paranoid schizophrenic patients were assessed by positron emission tomography (PET) and plasma biochemistry studies before and after ECT. The present study included five patients whose average age was 41.4 years. The average duration of illness was 23.0 years. To avoid any effect of changes in drugs on PET, no changes were made in the medication of any of the five patients during the study period. ECT improved the clinical symptoms in every patient. Regional cerebral blood flow (rCBF) on PET in both temporal lobes and the left cerebellum was higher in paranoid schizophrenia before ECT than in normal subjects, and rCBF after ECT in both frontal lobes, the right temporal lobe and the right putamen was lower than before ECT as mental symptoms improved. These findings suggest high cerebral blood flow volume in paranoid schizophrenia. Plasma biochemistry studies revealed a lower level of 3-methoxy-4-hydroxyphenylglycol (MHPG) after ECT than before ECT, but a higher level of prolactin existed.

Adult↗
PubMed1992

Fetal urine biochemistry: an index of renal maturation and dysfunction.

OBJECTIVE: To construct a reference range for fetal urinary sodium, potassium, urea, creatinine, calcium and phosphate with gestation and to assess to what extent these biochemical indices are modified in fetuses with lower urinary tract obstruction. DESIGN: Prospective descriptive study. SETTING: Royal Postgraduate Medical School London. SUBJECTS: 24 women between 17 and 35 weeks gestation with an ultrasound diagnosis of fetal lower urinary tract obstruction, with or without renal dysplasia and a control group of 26 women between 16 and 33 weeks gestation with normal amniotic fluid volume and fetal anatomy. INTERVENTIONS: Fetal urine samples (1-100 ml) were aspirated from the control fetuses either before termination of pregnancy (n = 9) or at the time of intrauterine transfusion for Rh alloimmunization (n = 17). The fetuses with obstructive uropathy had urine samples aspirated on one occasion (n = 14) or serially (n = 10). MAIN OUTCOME MEASURES: Relation between urine biochemistry and renal damage ascertained clinically or at postmortem. RESULTS: In the control group, urinary sodium and phosphate decreased and creatinine increased significantly with gestational age, consistent with increasing fetal glomerular filtration rate and progressive maturation of tubular function. Urinary sodium and calcium were significantly higher in fetuses with renal dysplasia compared with those with lower urinary tract obstruction but normal renal histology or normal clinical outcome. Serial urinary samples from fetuses with obstructive uropathy showed more pronounced deviation from the normal with increasing gestation in all fetuses with renal dysplasia. The highest sensitivity in the detection of renal dysplasia was shown by urinary calcium (100%) whereas urinary sodium showed the best specificity (80%). CONCLUSION: Renal damage is the direct effect of urinary obstruction, rather than an association so that treatment should start as soon as possible. Urinary biochemistry may be helpful in the management of these patients.

Electrolytes↗
PubMed1991

B-50 (GAP-43): biochemistry and functional neurochemistry of a neuron-specific phosphoprotein.

The biochemistry and functional neurochemistry of the synaptosomal plasma membrane phosphoprotein B-50 (GAP-43) are reviewed. The protein is putatively involved in seemingly diverse functions within the nervous system, including neuronal development and regeneration, synaptic plasticity, and formation of memory and other higher cognitive behaviors. There is a considerable amount of information concerning the spatial and temporal localization of B-50 (GAP-43) in adult, fetal, and regenerating nervous tissue but far less is known about the physical chemistry and biochemistry of the protein. Still less information is available about posttranslational modifications of B-50 (GAP-43) that may be the basis of neurochemical mechanisms that could subsequently permit a variety of physiological functions. Hence, consideration is given to several plausible roles for B-50 (GAP-43) in vivo, which are discussed in the context of the cellular localization of the protein, significant posttranslational enzymes, and regulatory proteins, including protein kinases, phosphoinositides, calmodulin, and proteases.

Adrenocorticotropic Hormone↗
PubMed1999

Biochemistry and haematology values for the baboon (Papio hamadryas): the effects of sex, growth, development and age.

A retrospective study evaluated the influence of sex and age on plasma biochemistry and haematology parameters in a captive-bred colony of baboons. Over 1,140 ETDA and heparin blood samples were obtained from 160 clinically normal baboons between the ages of 11 months and 11 years. Data for these blood tests were analysed for the effects of sex, age and sex age interactions. Sex, age and sex age interactions were detected for many plasma biochemistry and haematological parameters. The reference range values for platelets, white-blood cells and mean corpuscular volume and plasma chloride, glucose, total protein and iron were higher (P < 0.01) and red blood cell, plasma sodium, potassium, total CO2, creatinine, urea, total bilirubin, albumin, alkaline phosphate, gamma glutamyl transpeptidase and phosphate were lower (P < 0.01) in the female compared to the male population. Sex age interactions (P < 0.05) were seen with haemoglobin, white blood cells, haematocrit, mean corpuscular volume, sodium, creatinine, urea, calcium, phosphate, total bilirubin, total protein alkaline phosphatase, the liver enzymes and triglycerides. Plasma alkaline phosphatase was highest ( > 800 micro/l) in young juveniles of both sexes; creatinine was higher in older ( > 4 years) compared to younger baboons of the same sex (P < 0.05). Plasma cholesterol and triglycerides were greater (P < 0.01) in young baboons compared to older animals.

Age Factors↗
PubMed2005

Clinical biochemistry of pregnant and nursing mares.

BACKGROUND: Pregnancy and lactation result in increased metabolic demands. Although homeostatic mechanisms function to keep substances in blood at relatively constant levels, some changes in the concentrations of routine clinical chemistry analytes are likely to occur. OBJECTIVES: The purpose of this study was to determine what physiological changes occur in serum clinical biochemistry analytes in pregnant and nursing mares, and to determine whether the changes were substantial enough to warrant separate reference intervals for pregnant or lactating horses. METHODS: Forty-two Quarter Horse, Thoroughbred, Saddlebred, Standardbred and Morgan mares were entered into the study while pregnant. They were bled once each month through birth. Studies were continued on 20 mares until their foals were weaned. Test results were tabulated by time before or after birth. Serum biochemistry values were determined by standard methods using automated analyzers. Test results were analyzed using the Kruskal-Wallis 1-way ANOVA on ranks. If a significant difference was found (P<.05), Dunn's multiple comparison procedure was performed on all pairs. Results from pregnant and nursing mares also were compared with a reference group of 19 open, nonlactating mares. RESULTS: Serum triglyceride, potassium, creatinine, and total bilirubin concentrations were lower during lactation than during pregnancy. Serum calcium concentration also was slightly decreased at 2 time points during lactation. Triglyceride concentration was highest during midgestation, while bilirubin and creatinine values increased, and potassium and calcium remained constant during pregnancy. Serum urea concentration also remained constant during pregnancy but increased during lactation. Serum phosphate concentration was lowest during midgestation and highest during lactation. Total CO2 values were highest, and anion gaps were lowest, during midgestation. No significant differences were found in serum albumin, globulin, albumin:globulin ratio, total protein, or glucose values. When compared with the reference group of open mares, serum triglyceride, potassium, bilirubin, and total CO2 concentrations were lower, and anion gap was higher in horses that were nursing. CONCLUSIONS: Although most biochemical values remained relatively constant, significant differences were observed during pregnancy and lactation. Changes in the concentrations of triglycerides, potassium, bilirubin, total CO2, and anion gap during lactation were substantial enough to warrant separate reference intervals for lactating horses.

Animals↗
PubMed1996

Daily fluctuations of haematology and blood biochemistry in horses fed varying levels of protein.

Changes in the plasma biochemistry of 12 stallions were studied over seven 24 h periods. Twelve healthy male horses of 4 different breeds (Thoroughbred [TB], Anglo-Arabo-Sardo [AAS], Avelignese [Av] and Maremmano [M]) were divided into 3 experimental groups and fed with an isoenergetic maintenance ration with different protein levels. The same amount of food was given daily at 0730 and 1930 h. After 20 days of pretrial, a series of 6 blood samples were collected daily from the jugular vein every 4 h for 7 days. The samples were analysed for packed cell volume (PCV), haemoglobin, plasma glucose, free fatty acids, cholesterol, total plasma protein, urea, creatinine, calcium, phosphorus and enzymatic activities: aspartate aminotransferase (AST), alanine aminotrasferase (ALT), creatine kinase (CK) and lactate dehydrogenase (LDH). The data were analysed following the armonic analysis (Fourier) in order to define the pattern of biorhythm. Many parameters showed a biorhythmical pattern. Protein levels of the diet failed to influence haematology, blood biochemistry and biorhythm. Thoroughbreds showed the highest values of PCV, haemoglobin and creatinine and the lowest total protein, phosphorus and enzymatic activities.

Analysis of Variance↗
PubMed1992

Biochemistry of nitric oxide and its redox-activated forms.

Nitric oxide (NO.), a potentially toxic molecule, has been implicated in a wide range of biological functions. Details of its biochemistry, however, remain poorly understood. The broader chemistry of nitrogen monoxide (NO) involves a redox array of species with distinctive properties and reactivities: NO+ (nitrosonium), NO., and NO- (nitroxyl anion). The integration of this chemistry with current perspectives of NO biology illuminates many aspects of NO biochemistry, including the enzymatic mechanism of synthesis, the mode of transport and targeting in biological systems, the means by which its toxicity is mitigated, and the function-regulating interaction with target proteins.

Amino Acid Oxidoreductases↗
PubMed1986

Patients with suspected myocardial infarction: their test request patterns for clinical biochemistry in a British and a Canadian cardiac care unit.

The total number of routine clinical biochemistry tests requested for patients admitted to a coronary care unit with a diagnosis of "query myocardial infarction" were recorded over four to eight months. There were 156 sequential admissions in a British teaching hospital and 163 in a Canadian counterpart; the incidence of confirmed myocardial infarction was 53% and 50%, respectively. The pattern of tests ordered was substantially similar in each unit, unlike the rate of testing. For example, total creatine kinase was requested five times less often per patient in the British hospital than in the Canadian unit in cases of confirmed myocardial infarction (2.17 and 10.17, respectively; p less than 0.0001): the difference was much less, but still significant, when there was no infarction (2.01 and 3.55; p less than 0.0001). This study suggests a significant international difference in the use of clinical biochemistry services between coronary care units. Physicians (clinical and laboratory) need to be more critical of their use of protocols, which may prove wasteful of limited health care resources.

Alanine Transaminase↗
PubMed1992

The biophysics and biochemistry of smooth muscle contraction.

In this review the biophysics and biochemistry of smooth muscle contraction are dealt with. We describe a new model for the study of bronchial smooth muscle, which facilitates study of cellular contractile mechanisms. A new concept emerging is that study of steady-state mechanical parameters such as maximal isometric force (Po) velocity is inadequate because two types of crossbridges (normally cycling (NBR) and latch) seem to be sequentially active during smooth muscle contraction. Thus quick-release techniques are required to characterize the force-velocity properties of the two types of bridges. Pathophysiological processes that affect the muscle's shortening ability seem to affect the early NBRs only. With respect to maximal shortening capacity of the smooth muscle, the role of loading is very important. The differences between isotonic, elastic, and viscous loading are considerable. Ultimately, the time course and magnitude of loading should exactly resemble that operative in vivo. Once again, it is the characteristic of loading in the early phase of contraction that is crucial, as most of the shortening in smooth muscle occurs early in the contraction. While the maximum force developed by smooth muscle per unit cross-sectional area is the same as for striated muscle, the velocity is 50 times less. The properties of the series and parallel elastic elements of smooth muscle are described. The latter, when in compression mode, acts as an internal resistance to shortening and probably limits it. Isotonic relaxation has therefore not been studied in smooth muscle. We have developed a shortening parameter that is independent of the load on the muscle and of the initial length of the muscle's contractile element. We report the novel observation that isotonically relaxing smooth muscle reactivates itself, resulting in terminal slowing of the relaxation process. With respect to the biochemistry of smooth muscle contraction, contractile (actin isoforms, myosin heavy and light chains and their isoforms), regulatory (calmodulin-4 Ca2+, myosin light chain kinase, myosin light chain and its phosphorylation, tropomyosin, caldesmon, and calponin), and cytoskeletal (chiefly desmin and vimentin) proteins are discussed. While the kinase activates the contractile system, caldesmon and calponin modulate the activity downward. The cytoskeletal proteins desmin, vimentin, and alpha-actinin could constitute the muscle cell's internal resistor.

Animals↗
PubMed1996

The biochemistry and genetics of capsular polysaccharide production in bacteria.

Bacterial polysaccharides are usually associated with the outer surface of the bacterium. They can form an amorphous layer of extracellular polysaccharide (EPS) surrounding the cell that may be further organized into a distinct structure termed a capsule. Additional polysaccharide molecules such as lipopolysaccharide (LPS) or lipooligosaccharide (LOS) may also decorate the cell surface. Polysaccharide capsules may mediate a number of biological processes, including invasive infections of human beings. Discussed here are the genetics and biochemistry of selected bacterial capsular polysaccharides and the basis of capsule diversity but not the genetics and biochemistry of LPS biosynthesis (for reviews see 100, 140).

Antigens, Bacterial↗
PubMedDate not supplied

Correlation of human age-related cataract with some blood biochemistry constituents.

PURPOSE: The causes of age-related cataract are multifactorial and particular consideration has been given to the role of nutritional factors in cataract formation. The purpose of this study was to determine the levels of certain blood biochemistry constituents in cataract patients and controls and evaluate their potential, if any, as identifying risk factors in cataractogenesis. METHODS: This is a case-control study where 155 cataract patients and 155 matched controls were chosen for evaluation. Cataract subjects were further divided into subgroups depending on the location of the cataract. All underwent routine eye examinations and blood samples were taken from each one for blood biochemistry analysis including serum levels of glucose, urea, cholesterol, triglycerides, total protein, albumin, bilirubin, calcium, sodium and potassium and the enzymes aspartate aminotransferase, alanine aminotransferase and alkaline phosphatase. RESULTS: Mean levels of total protein, bilirubin, calcium, sodium, alanine aminotransferase and alkaline phosphatase differed significantly between patient and control groups. Patients with posterior subcapsular cataract had significantly higher glucose levels (p = 0.05) compared with patients with other types of cataract. It was also found that those patients with a cortical cataract had the highest level of urea, differing significantly from other subgroups and controls. CONCLUSIONS: The mean levels of all constituents under study fell within normal body range. However, the levels of several important factors demonstrated a positive and significant correlation with cataract. While we do not presume to present these results as conclusive, it is possible that a gradual and constant variation in these parameters may be predisposing factors in cataractogenesis.

Adult↗