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F Millán

Publications and source records attributed to F Millán.

17 recordsLinked to original sources
PubMed2005

Composition and functional properties of Lupinus campestris protein isolates.

Protein isolates from L. campestris and soybean seeds were prepared using isoelectric precipitation (PI) and micellization (MI) procedures. The amount of protein recovered was considerably higher with the isoelectric precipitation than with the micellization procedure (60% and 30%, respectively). Protein contents were higher than 90% in protein isolates. Antinutritional factors content (alkaloids, lectins, and tannins) were reduced to innocuous levels after protein isolate preparation. Minimum protein solubility for the precipitated lupin protein isolate (LPI) was at pH 4.0, and between pH 4 and 6 for the micellized lupin protein isolate (LMI), increasing at both extremes of the pH scale. Water absorption for the LMI was 1.3 ml/g of protein and its oil absorption 2.2 ml/g of protein. The LPI had 1.7 ml/g of protein in both water and oil absorption. Foaming capacity and stability was pH-dependent. Foaming capacity was higher at pH 2 and lower near the protein isoelectric points. Minimum protein concentration for gelation in LMI was 8% w/v at pH 4, while for LPI was 6% at pH 4 and 6. Amino acid composition in L. campestris flour and protein isolates was high in lysine and low in methionine. Most of the essential amino acids in lupin protein isolates were at acceptable levels compared to a reference pattern for infants and adults. The electrophoretic pattern of both protein isolates showed three bands with different mobilities, suggesting that the protein fractions belong to alpha-conglutin (11S-like protein), beta-conglutin (7S-like protein) and gamma-conglutin. It is proven that some of the functional properties of L. campestris protein isolates are similar to those soybean protein isolates recovered under equal conditions.

Amino Acids↗
PubMed2004

Amino acids composition of Teucrium nutlet proteins and their systematic significance.

BACKGROUND AND AIMS: Plant species are considered as a good source of dietary proteins, although the nutritional quality of proteins depends on their amino acid composition. In this work the protein content and amino acid composition of nutlets of 21 Teucrium taxa (Lamiaceae) from Spain were analysed and their nutritional quality was compared with the minimum values established by the Food and Agriculture Organization of the United Nations (FAO). In addition, the amino acid composition was evaluated as a chemical character to clarify the taxonomic complexity in this genus. METHODS: Amino acid content of nutlets was determined after derivatization with diethyl ethoxymethylenemalonate by high-performance liquid chromatography. Previously, nutlets samples were hydrolysed and incubated in an oven at 110 degrees C for 24 h. KEY RESULTS: The protein content was variable, ranging from 6.4 % in T. dunense to 43.8 % in T. algarbiense. According to the FAO values all taxa contain satisfactory amounts of leucine, threonine and valine and are deficient in lysine. The similarity analysis of Teucrium taxa using amino acid composition data did not clearly reflect the infrageneric classification of this genus. CONCLUSIONS: Annual species, such as T. spinosum, T. aristatum and T. resupinatum showed a better balanced amino acid composition. The dendrogram partly matched with the karyological complexity of Teucrium. No correlation between amino acid composition and habitat has been observed, showing that Teucrium nutlet amino acid composition may not be strongly influenced by the environment.

Amino Acids↗
PubMed2001

Performance evaluation of a mesophilic anaerobic fluidized-bed reactor treating wastewater derived from the production of proteins from extracted sunflower flour.

A study of the anaerobic digestion of wastewater derived from the production of protein isolates from extracted sunflower flour was carried out in a laboratory-scale, mesophilic (35 degrees C) fluidized-bed reactor with saponite as bacterial support. Chemical oxygen demand (COD) removal efficiencies in the range of 98.3-80.0% were achieved in the reactor at organic loading rates (OLR) of between 0.6 and 9.3 g COD/I d, hydraulic retention times (HRT) of between 20.0 and 1.1 d and average feed COD concentration of 10.6 g/l. Eighty percent of feed COD could be removed up to OLR of 9.3 g COD/l d. The yield coefficient of methane production was 0.33 l of methane (at STP) per gram of COD removed and was virtually independent of the OLR applied. Because the buffering capacity of the experimental system was maintained at favorable levels with excess total alkalinity present at all loadings, the rate of methanogenesis was not affected by loading. The experimental data indicated that a total alkalinity in the range of 2,000-2,460 mg/l as CaCO3 was sufficient to prevent the pH from dropping to below 7.0 for OLR of up to 9.3 g COD/l d. The volatile fatty acid (VFA) levels and the VFA/alkalinity ratio were lower than the suggested limits for digester failure (0.3-0.4) for OLR and HRT up to 9.3 g COD/l d and 1.1 d, respectively. For a HRT of 0.87 d (OLR of 12.1 g COD/l d) the start of acidification was observed in the reactor.

Fatty Acids↗
PubMed2001

Alcalase rapeseed inhibitors: purification and partial characterization.

Extensive rapeseed protein hydrolysate obtained sequentially with Alcalase and Flavourzyme showed inhibitory activity towards Alcalase. Inhibitory activity decreased as the hydrolytic process progressed probably by heat denaturation and/or partial protease degradation. Alcalase rapeseed inhibitors were purified by gel filtration and subsequent ion exchange chromatography. They are composed of peptides of 8.4 and 6.1 kDa linked by interchain disulphide bonds, as observed by reducing SDS-PAGE, with a native molecular weight of 18 kDa. Aminoacid composition of the inhibitors was characterized by the high proportion of methionine (4.2%) and cysteine (4.6%). Alcalase inhibitors were partially resistant to heat treatment; after heating at 70 degrees C for 45 minutes more than 50% of the original inhibitory activity remained in the purified protein but after heating at 90 degrees C for 5 minutes, inhibitory activity decreased very fast to a basal level. The possible relation of these protease inhibitors with the 2S albumin storage proteins is discussed.

Amino Acids↗
PubMed2001

[Analysis and clinical course of residual lithiasis after shock wave renal treatment].

OBJECTIVE: Although residual lithiasis after the application of shock waves is a situation that coexists with the procedure, in some cases it can be considered to be a failure of ESWL. The natural history and outcome of 244 cases of residual renal stone followed over a 5-year period are analyzed, and the approach based on a pre-established classification is discussed. METHODS: Of 1,407 patients treated by ESWL for renal lithiasis during 1995, 244 cases with a renal calculus larger than 3 mm were followed for a period of 5 years after treatment and evaluated by clinical, radiological, ultrasound and analytical methods. RESULTS: At 3 months post-ESWL, 1,013 cases (72%) were completely stone-free and 394 (28%) showed residual stone; of these, 244 (62%) had residual stone fragments greater than 3 mm. At 5 years, 190 (78%) remained stable and the remaining 54 (22%) showed stone regrowth that warranted additional treatments: 52 ESWL, 1 PNL and 1 partial nephrectomy. Despite the retreatments, only 42% became completely stone-free. CONCLUSIONS: A classification of residual renal stone can be established based on the data obtained to orient the approach in each case, although the frequency of residual stone can be reduced by the appropriate indication of ESWL. Once a renal stone has formed retreatments with ESWL cannot ensure complete elimination of the stone.

Humans↗
PubMed2001

[Cystinuria and cystine kidney lithiasis. Diagnosis and therapeutic approach].

OBJECTIVE: Cystine renal stone is the only clinical consequence of cystinuria, an autosomal recessive hereditary disease that affects an average of 1 out of 7,000 newborns, and whose geographical distribution varies significantly. The diagnosis and treatment of this condition is reviewed in the light of the advances in genetics and molecular biology. METHODS: The evolution of current knowledge about this disease is reviewed. RESULTS/CONCLUSIONS: The advances over the last 8 years have led to the characterization, at the present time, of two genes responsible for this disease, which demonstrates its polygenic origin. By phenotype, cystinuria can be classified into two types: type 1 and non-type 1. Both types show genetic and biochemical, but not clinical differences. From the therapeutic viewpoint, the main objective is to eliminate existing calculi and, above all, prevent recurrence by acting on the pathophysiologic mechanisms of renal cystine. Experience shows that despite the correct use of our current therapeutic armamentarium and the application of the general guidelines discussed in this paper, some cystinuric patients still maintain an important stone-forming activity. Patient clinical evaluation and a genetic study of both patient and family will be decisive for phenotyping.

Cystine↗
PubMed2000

Management of superficial transitional cell carcinoma in the intramural ureter: what to do?

PURPOSE: We analyze the evolution of superficial transitional cell carcinoma in the intramural distal ureter treated with transurethral resection. MATERIALS AND METHODS: A total of 19 patients underwent transurethral resection of the intramural distal ureter with a mean followup of 57 months. All cases were diagnosed as superficial transitional cell carcinoma and all but 2 had a history of bladder tumor. Upper urinary tract followup consisted of excretory urography every 6 months and ureterorenoscopy in cases with a doubtful diagnosis or positive cytology. RESULTS: Pathological examination revealed stage Ta disease in 42%, T1 in 31.5% and Tx in 26.3% of intramural tumors. Upper urinary tract recurrence was noted in 8 patients (42.1%), including 5 (62.5%) with involvement of the distal ureter. Nontumoral stenosis of the distal ureter in 3 cases was treated endoscopically. An endoscopic procedure resolved 75% of recurrences. A high surgical risk patient who did not undergo open surgery died of recurrence. CONCLUSIONS: Superficial transitional cell carcinoma of the intramural ureter is uncommon in the setting of multiple bladder tumors and recurrent bladder carcinoma. There was a 42.1% rate of ipsilateral recurrence and endoscopic treatment allowed us to preserve 89.5% of the involved renal units. Closer followup of the urinary tract must be performed since these tumors have a higher incidence of upper urinary tract recurrence.

Aged↗
PubMed1999

Purification and partial characterization of chickpea 2S albumin.

A chickpea 2S albumin has been purified by solubilization in 60% methanol and ion-exchange chromatography. Under denaturing conditions it is composed of two peptides of 10 and 12 kDa. Native molecular mass determined by gel filtration chromatography is 20 kDa. Amino acid composition shows that it is rich in sulfur amino acids, mainly cysteine with 4.6% of the total. On the other hand, it has antinutritional characteristics of being allergenic for chickpea-sensitive individuals and inhibitory against porcine chymotrypsin with a lesser degree toward trypsin. The results of interest from a nutritional point of view are discussed.

2S Albumins, Plant↗
PubMed1999

Interaction of chickpea (Cicer arietinum L.) legumin with oxidized linoleic acid.

Chickpea legumin has been purified and incubated under oxidizing conditions with linoleic acid to investigate the influence of this acid on the structure and nutritional quality of the protein. At the end of the incubation time, >30% of the linoleic acid was oxidized. The oxidized linoleic acid was highly detrimental to legumin, and the electrophoretic pattern of the protein was completely changed after the incubation period. Nevertheless, neither polymerization nor cleavage of the protein was observed as deduced from gel filtration chromatography, suggesting that the changes observed in native electrophoresis were probably due to oxidation of legumin. The incubation of legumin with linoleic acid also produced a diminution of the contents of methionine and histidine, by 81.3 and 24.3%, respectively. Finally, in vitro protein digestibility of chickpea legumin was also seriously affected by the incubation with linoleic acid, decreasing from 84.1 to 69.2%.

Amino Acids↗
PubMed1999

Production of extensive chickpea (Cicer arietinum L.) protein hydrolysates with reduced antigenic activity.

Chickpea protein isolate was used as starting material for the production of hypoallergenic protein hydrolysates. Western blotting of the protein isolate showed that IgE in sensitized patient sera strongly bound to the basic polypeptidic chains and recognized the acidic ones of 11S globulin. During the hydrolysis process by the individual and/or sequential action of endo- and exoproteases, a high reduction of antigenic activity was observed. Results suggest that the presence of intact or partially hydrolyzed basic polypeptide chains of 11S globulin are responsible for the formation of IgE complexes in protein hydrolysates obtained by exoprotease treatment; however, the digestion of these polypeptide chains by individual action of endoprotease caused a high loss of antigenic activity. The most effective reduction of antigenicity, >90%, was observed in extensive hydrolyzed chickpea proteins obtained by sequential treatment with endo- and exopeptidases. This chickpea protein hydrolysate could be useful for the elaboration of specialized hypoallergenic food products.

Blotting, Western↗
PubMedDate not supplied

[Complete congenital heart block. Its natural history and evolution].

This study describes the natural history and evolution of 67 patients with congenital auriculoventricular heart block admitted in the Instituto Nacional de Cardiología "Ignacio Chávez", Mexico, D.F. from 1944 to 1998. There were 35 (52%) females and 32 (47%) males, with mean follow up period of 93.7 +/- 104 months. Most of the patients were without structural cardiovascular disease (90%). The most frequent symptoms were dyspnea and syncope. Electrocardiograms showed a ventricular heart rate of 42.2 +/- 9 beats/minute. 85.7% of patients had a supra-Hisian complete heart block. In 31% of patients a pacemaker was implanted because syncope. Overall mortality was 4.4% and malignant ventricular arrhythmias were the principal contributors. Risk factors for mortality identified in this study were junctional escape rhythm lower than 50 beats/minute, inappropriate chronotropic response during exercise, R-R interval prolongation at night, enlargement of cardiac chambers, depressed left ventricular ejection fraction and prolonged QT interval. In all of these conditions we recommend permanent pacemaker implantation.

Adolescent↗
PubMedDate not supplied

[A complete atrioventricular block during exertion].

Exercise-induced atrioventricular (AV) block in patients with normal electrocardiogram at rest is uncommon. We report the clinical features of two patients with AV block during treadmill test. The first patient was a woman of 54 years of age with presyncope on exercise. She developed complete AV block during exercise testing without evidence of ischemic myocardial disease. Electrophysiologic study documented distal AV block. The second patient was a man 31 years old who developed angina and third-degree AV block with depression of ST segment during treadmill test. Myocardial perfusion study suggested ischemic heart disease. He received anti-ischemic drugs with improvement of symptoms. A control exercise testing demonstrated normal AV conduction and electrophysiologic study was normal. In the first case, exercise AV block was probably due to abnormal His Purkinje conduction system refractoriness to autonomic modulation, while in second case AV block was secondary to ischemic heart disease. Third-degree AV block at exercise can be present in patients without conduction system abnormalities at rest. Exercise-induced infra-Hisian AV block must be treated with pacing until ischemic heart disease has been ruled out.

Adult↗