Resultados en salud tras la implantación de una guía multidisciplinar para la atención a la fractura de cadera / Health outcomes after the implementation of multidisciplinary clinical guidelines for the care of hip fractures

Antecedentes y objetivo: Evaluar el impacto de la aplicación de una guía clínica multidisciplinar en el proceso de atención a pacientes con fractura de cadera. Material y métodos: Estudio prospectivo pre y postintervención en una Unidad de Ortogeriatría de un hospital de segundo nivel tras implementar una guía clínica multidisciplinar de atención a la fractura de cadera. Se analizan las características basales de los pacientes y las variaciones observadas en las variables de proceso y de desenlace en los 2períodos estudiados (junio del 2015-mayo del 2016 y junio del 2016-mayo del 2017). Resultados: Las características basales de la población fueron similares en el período preintervención (n = 455) y en el período postintervención (n = 456). La edad media de los pacientes fue 84,8 ± 6,8 años y un 70,8% eran mujeres. La aplicación de la guía clínica multidisciplinar produjo una reducción de la estancia media (16,9 días vs. 15,6 días, p = 0,014) y mejoró la prescripción del tratamiento de la osteoporosis (51,6% vs. 88%, p < 0,001), y redujo los episodios de delirio (44% vs. 31,2%, p < 0,001), broncoespasmo (18,3% vs. 12%, p = 0,019), insuficiencia cardíaca (20% vs. 11,5%, p < 0,001) y enfermedad pulmonar obstructiva crónica agudizada (7,9% vs. 3,8%, p = 0,017). Observamos un incremento de las úlceras por presión al alta (2,9% vs. 9%, p = 0,001). No hubo diferencias en la proporción de pacientes operados en menos de 48 h (56% vs. 61,2%, p = 0,64), en reingresos hospitalarios (6,9% vs. 5,9%, p = 0,51) ni en mortalidad (5,0% vs. 7,2%, p = 0,17). Conclusiones: La implantación de una guía clínica multidisciplinar mejoró aspectos del proceso de atención a los pacientes con fractura de cadera (AU)

Background and objectives: This study aims to evaluate the impact of implementing multidisciplinary clinical guidelines in the process of caring for patients with hip fractures. Materials and methods: This work is a pre- and post-intervention prospective study in the Orthogeriatrics Unit of a second-level hospital after implementing multidisciplinary clinical guidelines for hip fracture care. We analyzed patients’ baseline characteristics and the variations observed in care provided and in outcome variables in the 2periods studied (June 2015-May 2016 and June 2016-May 2017). Results: The baseline characteristics of the population were similar in the pre-intervention period (n=455) compared to the post-intervention period (n=456). Patients’ mean age was 84.8 ± 6.8 years and 70.8% were women. The implementation of the multidisciplinary clinical guidelines led to a reduction in the mean length of hospital stay (16.9 days vs 15.6 days, p=.014); improved osteoporosis treatment prescribing (51.6% vs 88%, p<.001); and reduced episodes of delirium (44% vs 31.2%, p<.001), bronchospasm (18.3% vs 12%, p=.019), heart failure (20% vs 11.5%, p<.001), and COPD exacerbation (7.9% vs 3.8%, p=.017). We observed an increase in pressure ulcers at discharge (2.9 vs 9%, p<.001). There were no differences in the percentage of operations in less than 48hours (56% vs 61.2% p=.64), hospital readmissions (6.9% vs 5.9%, p=.51), or mortality (5.0% vs 7.2%, p=.17). Conclusions:The implementation of multidisciplinary clinical guidelines improved aspects of the care process for patients with hip fracture (AU)

Health outcomes after the implementation of multidisciplinary clinical guidelines for the care of hip fractures.

BACKGROUND AND OBJECTIVES: This study aims to evaluate the impact of implementing multidisciplinary clinical guidelines in the process of caring for patients with hip fractures. MATERIALS AND METHODS: This work is a pre- and post-intervention prospective study in the Orthogeriatrics Unit of a second-level hospital after implementing multidisciplinary clinical guidelines for hip fracture care. We analyzed patients' baseline characteristics and the variations observed in care provided and in outcome variables in the two periods studied (June 2015-May 2016 and June 2016-May 2017). RESULTS: The baseline characteristics of the population were similar in the pre-intervention period (n = 455) compared to the post-intervention period (n = 456). Patients' mean age was 84.8 ± 6.8 years and 70.8% were women. The implementation of the multidisciplinary clinical guidelines led to a reduction in the mean length of hospital stay (16.9 days vs. 15.6 days, p= .014); improved osteoporosis treatment prescribing (51.6% vs. 88%, p< .001); and reduced episodes of delirium (44% vs. 31.2%, p < .001), bronchospasm (18.3% vs. 12%, p = .019), heart failure (20% vs. 11.5%, p < .001), and COPD exacerbation (7.9% vs. 3.8%, P = .017). We observed an increase in pressure ulcers at discharge (2.9 vs. 9%, P < .001). There were no differences in the percentage of operations in less than 48 h (56% vs. 61.2% p = .64), hospital readmissions (6.9% vs. 5.9%, p = .51), or mortality (5.0% vs. 7.2%, p = .17). CONCLUSIONS: The implementation of multidisciplinary clinical guidelines improved aspects of the care process for patients with hip fracture.

Insights into the preclinical treatment of blood-stage malaria by the antibiotic borrelidin.

BACKGROUND AND PURPOSE: Blood-stage Plasmodium parasites cause morbidity and mortality from malaria. Parasite resistance to drugs makes development of new chemotherapies an urgency. Aminoacyl-tRNA synthetases have been validated as antimalarial drug targets. We explored long-term effects of borrelidin and mupirocin in lethal P. yoelii murine malaria. EXPERIMENTAL APPROACH: Long-term (up to 340 days) immunological responses to borrelidin or mupirocin were measured after an initial 4 day suppressive test. Prophylaxis and cure were evaluated and the inhibitory effect on the parasites analysed. KEY RESULTS: Borrelidin protected against lethal malaria at 0.25 mg·kg⁻¹·day⁻¹. Antimalarial activity of borrelidin correlated with accumulation of trophozoites in peripheral blood. All infected mice treated with borrelidin survived and subsequently developed immunity protecting them from re-infection on further challenges, 75 and 340 days after the initial infection. This long-term immunity in borrelidin-treated mice resulted in negligible parasitaemia after re-infections and marked increases in total serum levels of antiparasite IgGs with augmented avidity. Long-term memory IgGs mainly reacted against high and low molecular weight parasite antigens. Immunofluorescence microscopy showed that circulating IgGs bound predominantly to late intracellular stage parasites, mainly schizonts. CONCLUSIONS AND IMPLICATIONS: Low borrelidin doses protected mice from lethal malaria infections and induced protective immune responses after treatment. Development of combination therapies with borrelidin and selective modifications of the borrelidin molecule to specifically inhibit plasmodial threonyl tRNA synthetase should improve therapeutic strategies for malaria.

In vitro and in vivo expression of human erythrocyte pyruvate kinase in erythroid cells: a gene therapy approach.

Human pyruvate kinase deficiency (PKD), an autosomal recessive disorder produced by mutations in the PKLR gene, is the most common cause of chronic nonspherocytic hemolytic anemia. Transduction of wild-type erythroid (R-type) pyruvate kinase (RPK) cDNA into deficient hematopoietic stem cells could be of potential use as rescue therapy in severe clinical cases. In this study, gammaretroviral vectors expressing human RPK were designed as possible gene therapy candidates for this disease. Through real-time quantitative reverse transcriptase-polymerase chain reaction, Western blotting, and flow cytometric analysis, we demonstrate stable RPK expression in both undifferentiated and differentiated murine erythroleukemia cells. In this in vitro assay, the proportion of transduced cells and the intensity of expression of the transgene remained unaltered after 6 months of culture. Moreover, transplanting human RPK-transduced Lin(-)Sca-1(+) mouse cells in myeloablated primary and secondary recipients rendered high proportions of erythroid precursors and mature erythrocytes expressing RPK, without inducing hematopoietic effects. These findings suggest that retroviral vectors could be useful for the delivery and expression of RPK in erythroid cells, and provide evidence of the potential use of gene therapy strategies to phenotypically correct erythroid PKD.

Assessment of dietary nutrients that influence perception of intra-oesophageal acid reflux events in patients with gastro-oesophageal reflux disease.

BACKGROUND: Gastro-oesophageal reflux disease symptoms are most commonly reported postprandially, suggesting that some diet components are likely to induce symptoms more than others. AIMS: To determine which of the various dietary nutrients is a strong predictive factor for symptom generation in association with an acid reflux event. METHODS: Subjects with typical heartburn symptoms were evaluated by the gastro-oesophageal reflux disease Symptom Checklist, demographics questionnaire, upper endoscopy and pH testing. During the pH study, patients completed a detailed 24-h dietary intake record. This included time of meals, description of food components and the amount and type of food preparation. RESULTS: Fifty gastro-oesophageal reflux disease patients completed all stages of the study. A total of 112 (78%) symptoms were considered as sensed reflux event. Body mass index did not correlate with having perceived reflux. Patients who consumed more cholesterol, saturated fatty acids and had more percentage calories from fat were significantly more likely to experience a perceived reflux event. Regression analysis and beta-coefficient were specifically significant for cholesterol. CONCLUSION: Of all dietary nutrients, cholesterol enhances the most the perception of intra-oesophageal acid reflux events in patients with gastro-oesophageal reflux disease.

Functional analysis of gammaretroviral vector transduction by quantitative PCR.

BACKGROUND: In a clinical setting of gene therapy, quantitative methods are required to determine recombinant viral titres and transgene mRNA expression, avoiding the use of reporter genes. METHODS: We describe procedures based on quantitative polymerase chain reaction (qPCR) designed to assess functional titres of murine leukaemia virus (MLV) vectors, determine proviral copy numbers in transduced cells, and estimate retroviral transgene expression in both target cell lines and mice with transduced chimeric haematopoiesis. RESULTS: Compared to EGFP titration, proviral DNA detection by qPCR was more accurate in assessing the number of infective particles in supernatants, such that average viral titres in terms of proviral copies per cell were two-fold higher. Transgene mRNA expression was directly determined from the vectors used without the need for reporter assays. A new parameter, defined here as the 'transcription index' (TI), served to establish the association between transcribed transgenic mRNA and each proviral insertion. The TI represents the potential expression of every vector or insertion in each cell type, and is thus useful as a control parameter for monitoring preclinical or clinical protocols. CONCLUSIONS: The practical use of qPCR is demonstrated as a valuable alternative to reporter genes for the assessment and surveillance of insertion numbers and transgene expression. In combination with protein expression, this approach should be capable of establishing safer therapeutic gene doses, avoiding the potential side effects of high transduction and expression levels.

Effect of dietary fish oil substitution with linseed oil on the performance, tissue fatty acid profile, metabolism, and oxidative stability of Atlantic salmon.

The objective of this experiment was to test the effect of total or partial substitution of dietary fish oil (FO) by linseed oil (LO) in Atlantic salmon feeding on performance, liver and muscle fatty acid composition, selected lipogenic and lipolytic enzyme activities, and flesh oxidative stability. For 12 wk, fish (220 +/- 12 g of initial BW) were fed five experimental diets in which the FO was serially replaced by 25, 50, 75, and 100% LO. Total FO replacement by LO did not (P = 0.20) affect fish final weight, biometric indices, or i.m. fat contents. Liver and muscle neutral lipid (NL) composition responded to dietary treatments in different ways. Whereas the sum of n-3 PUFA in muscle followed a linear and quadratic pattern with increasing levels of LO, a linear (P = 0.005) effect was observed in the liver NL fraction. Total n-3 and n-6 PUFA contents in the polar lipid fraction (PL) were unaffected (P = 0.356) by dietary input of LO in muscle. Activity of liver glucose-6-P-dehydrogenase (G6PD) was greater with increasing levels of LO (P = 0.004). A time effect (P < 0.001) was observed in the concentration of lipid peroxidation products, expressed as thiobarbituric acid reactive substances, in fish flesh stored under refrigeration for 9 d; however, the progressive inclusion of LO in the feed did not affect (P = 0.125) flesh oxidation stability. In summary, LO can totally replace FO in Atlantic salmon feed without affecting growth performance and muscle susceptibility to lipid oxidation. Fatty acid metabolism in the liver was affected by LO, promoting G6PD activity and eicosatetraenoic acid accumulation; however, a 100% LO replacement decreased (P < 0.001) concentrations of eicosapentaenoic and docosahexaenoic acids in salmon muscle.

Dietary protein source affects lipid metabolism in the European seabass (Dicentrarchus labrax).

The study was undertaken to evaluate the effects of dietary protein sources on lipogenesis and fat deposition in a marine teleost, the European seabass (Dicentrarchus labrax). Four isonitrogenous (crude protein (CP, Nx6.25), 44% DM) and isoenergetic (22-23 kJ/g DM) diets were formulated to contain one of the following as the major protein source: fish meal (FM), one of two soy protein concentrates (SPC) and corn gluten meal (CGM). Apparent digestibility coefficients of the diets and raw ingredients, as well as soluble nitrogen (ammonia and urea) and phosphorus excretion were measured. Growth rates of seabass fed plant protein-based diets were significantly lower than those fed fish meal based diet. The protein utilisation was strongly correlated to the dietary essential amino acids index. Measurements of N excretion (ammonia and urea nitrogen) confirmed these data. Daily fat gain at the whole body level ranged between 1.1 to 1.7 g/kg BW, with the highest values being recorded in fish fed the fish meal based diet. Levels of plasma triglycerides and cholesterol were lower in fish fed soy protein diets than in those fed the diet solely based on fish meal. Soy protein rich diets decreased the activities of selected hepatic lipogenic enzymes (glucose 6-phosphate dehydrogenase, malic enzyme, ATP-citrate lysase, acetylcoenzyme A carboxylase and fatty acid synthetase). Highest lipogenic enzyme activities where found in fish fed the fish meal diet, except for fatty acid synthetase which was increased in seabass fed the corn-gluten meal based diets. Overall data suggest that dietary protein sources affects fat deposition and the lipogenic potential in European seabass.

Adaptation of lipid metabolism, tissue composition and flesh quality in gilthead sea bream (Sparus aurata) to the replacement of dietary fish oil by linseed and soyabean oils.

Linseed (LO) and soyabean (SO) oils were evaluated as fish-oil (FO) substitutes in the diets of marketable-sized gilthead sea bream (Sparus aurata). Practical diets were designed factorially with the lipid added as follows (%): FO 100, LO 60+FO 40, LO 80+FO 20, SO 60+FO 40, SO 80+FO 20. The effects of experimental diets on growth, fatty acids patterns in liver and muscle, flesh quality variables and activities of selected enzymes involved in lipid synthesis and catabolism were determined at the end of a 7-month trial. Fatty acid composition of liver and muscle generally reflected the fatty acid composition of the diets. The n-3 PUFA levels were significantly reduced by the inclusion of vegetable oils. This tendency was more pronounced for EPA than for docosahexaenoic acid. The n-3:n-6 fatty acid ratio reached the lowest values in fish fed the SO diets; this was associated with a higher liver lipid deposition. No differences were found in fillet texture and pH. However, under conditions of forced peroxidation, muscles from fish fed the SO diets had lower peroxidation levels. Vegetable oil substitution decreased lipogenesis in liver and this effect was greatest at the highest substitution level. In contrast, muscle beta-oxidation enzymes had increased activities with vegetable oil substitution. Thus, the lower hepatic lipogenesis was correlated with an increased lipid utilisation in muscle. It is concluded that growth and lipid metabolism were affected by experimental diets.

The use of fluorescent molecular beacons in real time PCR of IgH gene rearrangements for quantitative evaluation of multiple myeloma.

UNLABELLED: BACKGROUND AND OBJECTIVES Fluorescent molecular beacons have been employed as hybridization probes in real time quantitative PCR to quantify residual disease in multiple myeloma (MM). DESIGN AND METHODS: After clinical diagnosis of MM, the CDR1, CDR2 and CDR3 regions of the IgH gene were analysed and sequenced to identify its clonal nature. Unique sequences of the clonal IgH rearrangement were used to design specific molecular beacon probes for each MM patient. A molecular beacon probe for the beta-globin gene was used as a reference control to calculate relative amounts of the clonal B-cell population. RESULTS: Optimization of probe design resulted in the use of a competitive sequence at the IgH area target between the loop and part of the stem of the molecular beacon. Cycling conditions and fluorescence temperature acquisition were optimized for a Light Cycler. To validate this method for the follow-up of treated MM patients, we investigated accuracy, as well as interassay and intrassay reproducibility. CONCLUSIONS: Our results indicated that real time PCR with specific molecular beacons provides a feasible, accurate and reproducible method for the determination of minimal residual disease in MM.

Hipotensión ortostática en el anciano / Orthostatic hypotension in the elderly

En esta revisión se repasan las principales carac terísticas de la hipotensión ortostática que ocurre en el anciano. Se trata de una patología poco estudiada y poco detectada en las consultas de Atención Primaria. Se quiere resaltar su enorme preva lencia, la necesidad de una detección sistemática, la dificultad en el estudio diagnóstico, su importancia como factor de riesgo vascular en el grupo de pacientes con 65 años o más y se quieren dar pautas de abordaje y tratamiento desde la Atención Primaria (AU)

Evolution of the mitochondrial control region in Palaearctic brown trout (Salmo trutta) populations: the biogeographical role of the Iberian Peninsula.

In order to extend present knowledge of brown trout phylogeography in the Palaearctic, we analysed the complete mitochondrial D-loop sequence (1025-1027 bp) of all mitochondrial haplotypes of Salmo trutta found in the Iberian Peninsula and one North African haplotype. Sequence variation in the mitochondrial control region serves to identify four major haplotype groups within the Iberian Peninsula, i.e. Atlantic, Duero, Mediterranean and Andalusian. Including the Iberian haplotypes, the five main European groups previously established were increased to six: (i) an Atlantic group including two different clusters, South European and North Atlantic; (ii) a group representing an endemism restricted to the Duero basin in the Iberian Peninsula; (iii) an Adriatic-Andalusian group found in two vicariant areas including Adriatic-Ionian populations in the Mediterranean and the Andalusian basins of the southern Iberian Peninsula; (iv) a Mediterranean group with a distribution range that extends from the southwestern basins of the Iberian Peninsula to the Ionian basins of the Greek Peninsula; (v) a Danube group of wide distribution in the Black, Aral and Caspian basins; and (vi) a group comprising the S. t. marmoratus subspecies confined to the Adriatic Sea. The Iberian Peninsula appears to have acted as a physical boundary between haplotypes corresponding to Atlantic- and Mediterranean-draining rivers. Owing to its geographical position, this area has played a major role in present Palaearctic species distribution, as illustrated by its haplotype diversity.

Abdominal fat deposition and fatty acid synthesis are lower and beta-oxidation is higher in broiler chickens fed diets containing unsaturated rather than saturated fat.

We evaluated the effects of dietary fat type on fat metabolism and deposition in broiler chickens. Birds were fed diets containing either 8 g dietary saturated (beef tallow) or polyunsaturated fat (sunflower oil)/100 g for 32 d. The abdominal fat deposition of chickens fed the sunflower oil-enriched diet was significantly lower than that of chickens fed the tallow-enriched diet (2.63 +/- 0.47 versus 3.03 +/- 0.44 g/100 g live wt.; P = 0.033). The specific activities of heart carnitine palmitoyltransferase I and L-3-hydroxyacyl-CoA dehydrogenase were higher (P < or = 0.03) in chickens fed the sunflower oil-enriched diets, indicating a greater rate of beta-oxidation. Liver fatty acid synthetase activity was lower (P = 0.01) in chickens fed the sunflower oil-enriched diet, suggesting reduced hepatic lipogenesis in this group. Postprandial plasma triglyceride levels were significantly lower (P < 0.05) in birds fed the sunflower oil-enriched diet, indicating a higher rate of dietary lipid clearance from the bloodstream to tissues. In conclusion, the lower fat deposition observed in broilers fed sunflower oil-enriched diets appears to be the net result of an increased rate of lipid catabolism and lower rate of fatty acid synthesis despite higher dietary fat absorption.

Mitochondrial haplotype variation and phylogeography of Iberian brown trout populations.

The biogeographical distribution of brown trout mitochondrial DNA haplotypes throughout the Iberian Peninsula was established by polymerase chain reaction-restriction fragment polymorphism analysis. The study of 507 specimens from 58 localities representing eight widely separated Atlantic-slope (north and west Iberian coasts) and six Mediterranean drainage systems served to identify five main groups of mitochondrial haplotypes: (i) haplotypes corresponding to non-native, hatchery-reared brown trout that were widely distributed but also found in wild populations of northern Spain (Cantabrian slope); (ii) a widespread Atlantic haplotype group; (iii) a haplotype restricted to the Duero Basin; (iv) a haplotype shown by southern Iberian populations; and (v) a Mediterranean haplotype. The Iberian distribution of these haplotypes reflects both the current fishery management policy of introducing non-native brown trout, and Messinian palaeobiogeography. Our findings complement and extend previous allozyme studies on Iberian brown trout and improve present knowledge of glacial refugia and postglacial movement of brown trout lineages.

Supercritical carbon dioxide extraction of lipids from Eucalyptus globulus wood.

Various typical lipid components of wood extractives have been isolated from Eucalyptus globulus wood by supercritical carbon dioxide modified with methanol. The influence of various extraction parameters on the yield and qualitative composition of the extracts have been studied. The extracts were analyzed by gas chromatography-mass spectrometry and compared with those obtained by Soxhlet extraction with acetone, the standard method for the determination of wood extractives. The qualitative and quantitative results obtained by both methods were in good agreement. The experimental planning to asses the influence of pressure, temperature and percentage of methanol and their interactions on the extraction efficiency was carried out with a factorial design, followed by multiple linear regression algorithm.

Mitochondrial DNA haplotyping of Testudo graeca on both continental sides of the Straits of Gibraltar.

Testudo graeca is an endangered species of tortoise that inhabits Mediterranean areas of Africa, Asia, and Europe. Western populations are found on both sides of the Straits of Gibraltar. The effects of geographical isolation on genetic divergence were assessed by the sequence analysis of two mitochondrial DNA regions of the 12S rRNA and cytochrome b genes. Four different haplotypes were identified. A single haplotype was shared by all Spanish and some east Moroccan specimens. Two haplotypes were unique to the west Moroccan T. graeca populations and allowed the clear discrimination between individual specimens found west of the Moulouya River. Phylogenetic analysis based on the estimation of nucleotide sequence distances of the haplotypes suggests an African origin for the Spanish populations and a subspecies status for the west Moroccan pool.

Structural defects underlying protein dysfunction in human glucose-6-phosphate dehydrogenase A(-) deficiency.

The enzyme variant glucose-6-phosphate dehydrogenase (G6PD) A(-), which gives rise to human glucose-6-phosphate dehydrogenase deficiency, is a protein of markedly reduced structural stability. This variant differs from the normal enzyme, G6PD B, in two amino acid substitutions. A further nondeficient variant, G6PD A, bears only one of these two mutations and is structurally stable. In this study, the synergistic structural defect in recombinant G6PD A(-) was reflected by reduced unfolding enthalpy due to loss of beta-sheet and alpha-helix interactions where both mutations are found. This was accompanied by changes in inner spatial distances between residues in the coenzyme domain and the partial disruption of tertiary structure with no significant loss of secondary structure. However, the secondary structure of G6PD A(-) was qualitatively affected by an increase in beta-sheets substituting beta-turns related to the lower unfolding enthalpy. The structural changes observed did not affect the active site of the mutant proteins, since its spatial position was unmodified. The final result is a loss of folding determinants leading to a protein with decreased intracellular stability. This is suggested as the cause of the enzyme deficiency in the red blood cell, which is unable to perform de novo protein synthesis.

Short-term modulation of lipogenesis by macronutrients in rainbow trout (Oncorhynchus mykiss) hepatocytes.

Rainbow trout (Oncorhynchus mykiss) hepatocytes were cultured under simulated conditions of varying nutritional status to explore the short-term modulation by dietary substrates of the main lipogenic enzymes: glucose-6-phosphate dehydrogenase (G6PD), malic enzyme (ME), ATP-citrate lyase (ACL), acetyl-CoA carboxylase (ACoAC) and fatty acid synthetase (FAS). Primary cultures were individually exposed to varying amounts of glucose, hydrolysed casein and long-chain polyunsaturated fatty acids (PUFA) for 12 h. A second set of experiments was designed to evaluate the effects of mixing different relative amounts of these macronutrients in the culture medium. Glucose concentrations of up to 20-25 mm showed a stimulatory effect on G6PD, ME, ACL and ACoAC activity while an earlier inhibitory effect on FAS was observed at 10-20 mm glucose The use of hydrolysed casein as a nutritional source of amino acids inhibited the activity of FAS and ME and stimulated G6PD, ACoAC and ACL activity Low levels of linolenic acid exerted a stimulatory effect on all the lipogenic enzymes assayed with the exception of FAS, and increased amounts showed some inhibition of lipogenic activities Eicosapentaenoic acid and docosahexaenoic acid showed a similar effect, although the former strongly inhibited FAS activity while the latter showed greater potential to inhibit ACoAC and G6PD. A complete change in the relative levels of glucose, hydrolysed casein and PUFA in turn led to changes in the enzyme activity patterns observed. The present study shows the feasibility of exploring the direct regulation of lipogenesis in isolated fish cells by varying the relative amounts of main macronutrients, mimicking in vivo dietary conditions. It is felt that such an approach may serve to investigate the macronutrient regulation of other metabolic pathways.

Molecular basis and enzymatic properties of glucose 6-phosphate dehydrogenase volendam, leading to chronic nonspherocytic anemia, granulocyte dysfunction, and increased susceptibility to infections.

We have investigated the blood cells from a woman with a low degree of chronic nonspherocytic hemolytic anemia and frequent bacterial infections accompanied by icterus and anemia. The activity of glucose 6-phosphate dehydrogenase (G6PD) in her red blood cells (RBCs) was below detection level, and in her leukocytes less than 3% of normal. In cultured skin fibroblasts, G6PD activity was approximately 15% of normal, with 4- to 5-fold increased Michaelis constant (Km) for NADP and for glucose 6-phosphate. Activated neutrophils showed a decreased respiratory burst. Family studies showed normal G6PD activity in the RBCs from all family members, including both parents and the 2 daughters of the patient. Sequencing of polymerase chain reaction (PCR)-amplified genomic DNA showed a novel, heterozygous 514C-->T mutation, predicting a Pro172-->Ser replacement. Analysis of G6PD RNA from the patient's leukocytes and fibroblasts showed only transcripts with the 514C-->T mutation. This was explained by the pattern of X-chromosome inactivation, studied by means of the human androgen receptor (HUMARA) assay, which proved to be skewed in the patient, her mother, and one of the patient's daughters. Thus, the patient has inherited a de novo mutation in G6PD from her father and an X-chromosome inactivation determinant from her mother, causing exclusive expression of the mutated G6PD allele. Purified mutant protein from an Escherichia coli expression system showed strongly decreased specific activity, increased Km for NADP and for glucose 6-phosphate, and increased heat lability, which indicates that the defective phenotype is due to 2 synergistic molecular dysfunctions: decreased catalytic efficiency and protein instability.

Increased neuronal glucose-6-phosphate dehydrogenase and sulfhydryl levels indicate reductive compensation to oxidative stress in Alzheimer disease.

We analyzed glucose-6-phosphate dehydrogenase, the rate-controlling enzyme of the pentose phosphate pathway and free sulfhydryls, to study redox balance in Alzheimer disease. Glucose-6-phosphate dehydrogenase plays a pivotal role in homeostatic redox control by providing reducing equivalents to glutathione, the major nonenzymatic cellular antioxidant. There is a multitude of evidence that marks oxidative stress proximally in the natural history of Alzheimer disease. Consistent with a role for glutathione in defense against increased reactive oxygen, we found an upregulation of glucose-6-phosphate dehydrogenase together with increased sulfhydryls in Alzheimer disease. These data indicate that reductive compensation may play an important role in combating oxidative stress in Alzheimer disease.