High-pressure liquid chromatographic determination of ascorbic acid in cooked sausages

The purpose of this paper was to study and optimize both extraction and high-pressure liquid chromatography (HPLC)-UV detection procedures to develop a proper method for the determination of ascorbic acid content in cooked sausages. A simple and sensitive reversed-phase HPLC method for the NH2-bonded phase has been described for the determination of ascorbic acid content in cooked sausages. Various extracting agents were tested to solubilize the vitamin, with 5% (wt/vol) metaphosphoric acid giving the best results. Samples were chromatographed with UV detection at 248 nm on a 25-cm Spherisorb NH2 cartridge with a 0.4-cm inside diameter with a mixture of 0.02 M potassium phosphate buffer solution (pH 3.6) and acetonitrile (40:60, vol/vol) for the mobile phase. The method's precision within a day was 1.2%, and its precision between days was 3.8%. The detection limit was 1.6 mg/100 g. Recovery ranged from 91.4 to 96.2% for ascorbic acid added to meat samples. Twenty samples of six different products were analyzed in duplicate. For the samples analyzed, the mean value for ascorbic acid ranged between 21.555 and 24.899 mg/100 g of fresh weight.

Determination of vitamin B(6) in cooked sausages

A reverse-phase high-performance liquid chromatography (HPLC) method has been described for the determination of various active forms of vitamin B(6) in meat products. Different extracting agents were tested to solubilize fully the analyte for quantification. The best data were obtained by extracting the samples with 5% (w/v) metaphosphoric acid. Separation by HPLC was performed with fluorescence detection (excitation, 290 nm; emission, 395 nm), on a 10 cm x 0.46 cm i.d. Hypersil BDS C(18) 5 microm column using a mixture of 50 mM phosphate buffer (pH 3.2) and acetonitrile (99:1, v/v) as mobile phase. Precision of the method was 0.5% (within a day) and 4.3% (between days). The detection limits were 0.020 mg/100 g for pyridoxal and pyridoxamine, 0.017 mg/100 g for pyridoxamine phosphate, 0.500 mg/100 g for pyridoxal phosphate, and 0.033 mg/100 g for pyridoxol, with a signal-to-noise ratio of 3. The recovery ranged from 92.0 to 100.0%.

Simultaneous determination of nicotinic acid and nicotinamide in cooked sausages

A simple and sensitive method for determining simultaneously nicotinic acid and nicotinamide content in cooked sausages by ion-pair reversed-phase liquid chromatography is described. Samples are extracted with ultrapure water, centrifuged, deproteinized with zinc hydroxide, filtered, and chromatographed with UV detection at 261 nm on a 25 cm x 4 mm i.d. Spherisorb ODS-2 cartridge using as mobile phase a mixture consisting of 5 mM heptanesulfonic acid adjusted to pH 3.3 with phosphoric acid and acetonitrile (75:25, v/v). Both vitamins are measured on a reversed-phase column with a single ion-pair reagent. Precision of the method was 0.5 and 1.0% (within a day) and 2.3 and 4.5% (between days) for nicotinic acid and nicotinamide, respectively. The detection limit was 0.300 mg/100 g. The recovery was >92% of nicotinic acid and nicotinamide added to samples of meats. Twenty samples of six different products have been analyzed in duplicate. The mean value for nicotinic acid ranged between 0.908 and 1.267 mg/100 g of fresh weight and for nicotinamide between 1.968 and 2.880 mg/100 g of fresh weight.

Determination of total riboflavin in cooked sausages

A simple and rapid method for determining riboflavin content in cooked sausages by ion-pair reversed-phase liquid chromatography has been set up. Samples were subjected to acid and enzymatic hydrolysis. Sample extracts were directly chromatographed, avoiding purification and concentration treatment. Final determination was performed by high-performance liquid chromatography with fluorescence detector (excitation, 227 nm; emission, 520 nm), on a 25 cm x 4 mm i.d. Spherisorb ODS-2 cartridge using a mixture of 5 mM heptanesulfonic acid adjusted to pH 2.7 with phosphoric acid and acetonitrile (75:25, v/v) as mobile phase. Precision of the method was 1.3% (within a day) and 2.6% (between days). The detection limit was 0.015 mg/100 g. The recovery was >95%.

[The characteristics, management and prognosis of the acute myocardial infarct patient in the Valencian Community in 1995: the results of the PRIMVAC Registry (The Registry Project of Acute Myocardial Infarct in Valencia, Alicante and Castellón). As representatives of the PRIMVAC investigators]

BACKGROUND AND OBJECTIVES

Regional registers of patients with acute myocardial infarction are scarce in Spain. The PRIMVAC register (Proyecto de Registro de Infarto agudo de Miocardio de Valencia, Alicante y Castellón) was initiated to obtain updated information on the management of these patients in the Valencia Autonomous Community. Data of the first twelve months of the register are presented.

METHODS

The 17 participating hospitals cover 2,833,938 inhabitants. Demographic, clinical, procedural and outcome data as well as predictive variables of mortality were analysed in the patients with acute myocardial infarction during their stay in the coronary care units from 1 December 1994 to 30 November 1995.

RESULTS

During 12 months, 2,377 patients were included. Mean age was 65.3 years (SD 11.9) and 23.2% were female. Left ventricular failure was present in 39.8%. Thrombolytic therapy was applied in 42.1% with a median time delay of 195 min from chest pain onset. This time was longer in the women (250 min) and in the elderly (210 min). The in-coronary-care-unit-mortality rate was 13.9%. Age, female gender, diabetes, previous myocardial infarction, Q wave and right ventricular infarction independently predicted increased early mortality.

CONCLUSION

Present data show the feasibility of an acute myocardial infarction register in the Valencia Autonomous Community. Although an acceptable level of thrombolysis has been reached, the mortality rate is still high. The long delay in initiating thrombolysis, particularly in female and elderly patients is remarkable.

Determination of thiamin in cooked sausages

A reliable and rapid high-performance liquid chromatography (HPLC) method has been set up for the determination of total thiamin in difficult sample matrices such as cooked sausages. Different hydrolysis conditions and enzymes were tested to release the vitamin from its phosphate ester. The best data in the enzymatic digestion were obtained by incubating the samples with 6% clara-diastase at 50 degrees C for 3 h. After oxidation of thiamin to thiochrome, the sample extracts were purified by using a C(18) Sep-Pak cartridge. Final determination was performed by reversed-phase HPLC with fluorescence detector (excitation 360 nm, emission 430 nm), on a low-cost 25 cm x 4 mm i.d. Spherisorb C(8) cartridge using a mixture of 5 mM phosphate buffer pH 7.0 and acetonitrile (70:30, v/v) as mobile phase. Precision of the method was 1.5% (within a day) and 5. 2% (between days). The detection limit was 0.015 mg/100 g. All the recoveries from the different cooked sausages were better than 90% of thiamin hydrochloride added to samples of meats. In the samples analyzed, the mean value for thiamin was between 0.039 and 0.508 mg/100 g fresh weight.

[Differential characteristics and survival of women with acute myocardial infarction. Registry of Acute Myocardial Infarctions of the City of Valencia (RICVAL). Researchers of the RICVAL]

INTRODUCTION AND OBJECTIVES

The prevalence of women who are admitted to the hospital after acute myocardial infarction is lower to that of men and their prognosis is worse. The reason for these differences is unclear. We studied the demographic and historical variables, the evolution, treatment and early survival in 269 women included in the Register of Acute Myocardial Infarctions of the City of Valencia (RICVAL) and compared them with the 855 men included in the same Register.

PATIENTS AND METHODS

Register of patients admitted into a Coronary Care Unit in the City of Valencia since December, 1st, 1993 until November 30th, 1994.

RESULTS

23.9% of the patients were women with a mean age of 71.9 +/- 9 years; 46.8% of them were diabetics, 55.4% hypertensives, and 6.7% smokers. The women arrived for treatment later than men and 34.9% of them were thrombolised. The incidence in women of severe heart failure (Killip III and IV) was 40.1% and the mortality 29.7%. In women with thrombolytic treatment the mortality was 29.8%. In the logistic regression model performed, female sex predicted a higher mortality rate (odds ratio [OR] = 1.30; confidence interval [CI], 1.05-1.61).

CONCLUSIONS

Early mortality in women after acute myocardial infarction is higher than in men in the RICVAL Register. The longer delay in initiating medical care and thrombolysis might be the cause for the higher proportion of heart failure among women and explain their worse prognosis after an acute myocardial infarction compared to men.

[The RICVAL study. Acute myocardial infarct in the city of Valencia. Data on 1,124 patients during the first twelve months of the registry (December, 1993--November, 1994)]

BACKGROUND AND OBJECTIVES

Information on the management of acute myocardial infarction in Spain is still scarce. The Register of Acute Myocardial Infarction of Valencia City (RICVAL) was established to collect, in a prospectively and uniformly way, data of patients with acute myocardial infarctions discharged from Valencia coronary care units, in order to obtain updated information on the management of these patients. Data of the first twelve months of the register are presented.

METHODS

Using standardised variables, demographic, clinical, procedural and outcome data from patients with acute myocardial infarction were collected at the eight hospitals collaborating in the RICVAL, from 1 December 1993 to 30 November 1994.

RESULTS

The eight participating hospitals cover 1,665,720 people. During 12 months, 1,124 patients were discharged from the participating coronary care units. Mean age was 65.1 years and 23.9% were female. The case fatality rate was 16.9%. Left ventricular failure (Killip 2, 3 and 4) was present in 42%. Thrombolytic therapy was applied in 43.5% with a median time delay of 210 minutes from chest pain onset. The delay time in initiating thrombolysis was longer in the women and in the elderly.

CONCLUSION

Analysis of present data shows the feasibility of an acute myocardial infarction register in Valencia City. The RICVAL study will allow a better knowledge of demographic, clinical, procedural and outcome data in patients with myocardial infarction. The case fatality rate is still high when we consider that an acceptable level of thrombolytic therapy has been reached. The long delay time in initiating thrombolysis, particularly in the elderly and in the women, must be emphasized.

Incidence of community-acquired pneumonia and Chlamydia pneumoniae infection: a prospective multicentre study

This one year prospective multicentre study was designed to determine the incidence of community-acquired pneumonia in adults. It was carried out in primary health care centres and three reference hospitals, located in the 'Maresme' region (Barcelona, Spain) serving a population of 39,733 subjects over 13 years of age. Patients suspected of having contracted community-acquired pneumonia were visited by their family doctors and referred to the three reference hospitals for confirmation of the diagnosis. Patients attending the emergency services of these hospitals were also included. Urine and blood samples were obtained for culture, antigen detection, blood count, serological tests, blood gases and biochemical profile. The diagnosis of community-acquired pneumonia was made in 105 patients. Forty-six patients had an identifiable microbial etiology. Chlamydia pneumoniae was the most common pathogen (16 cases) followed by Streptococcus pneumoniae (13 cases) and Mycoplasma pneumoniae (8 cases). In conclusion; the annual incidence rate of community-acquired pneumonia in adults in this area was 2.6 cases per 1,000 inhabitants and Chlamydia pneumoniae was the most frequent causative pathogen.

Incidence of community-acquired pneumonia and Chlamydia pneumoniae infection: a prospective multicentre study

This one year prospective multicentre study was designed to determine the incidence of community-acquired pneumonia in adults. It was carried out in primary health care centres and three reference hospitals, located in the 'Maresme' region (Barcelona, Spain) serving a population of 39,733 subjects over 13 years of age. Patients suspected of having contracted community-acquired pneumonia were visited by their family doctors and referred to the three reference hospitals for confirmation of the diagnosis. Patients attending the emergency services of these hospitals were also included. Urine and blood samples were obtained for culture, antigen detection, blood count, serological tests, blood gases and biochemical profile. The diagnosis of community-acquired pneumonia was made in 105 patients. Forty-six patients had an identifiable microbial etiology. Chlamydia pneumoniae was the most common pathogen (16 cases) followed by Streptococcus pneumoniae (13 cases) and Mycoplasma pneumoniae (8 cases). In conclusion; the annual incidence rate of community-acquired pneumonia in adults in this area was 2.6 cases per 1,000 inhabitants and Chlamydia pneumoniae was the most frequent causative pathogen.

[Multicenter study of the prevalence of type 2 human immunodeficiency virus infection in Spain (1990)]

BACKGROUND

HIV-2 is a new retrovirus which may produce AIDS and has been mainly described in individuals from West Africa. More than 400 cases have been reported in France and Portugal while in Spain very few cases of HIV-2 infection have been reported with few studies having been made concerning the prevalence of the disease. This multicentric study analyzes the prevalence of HIV-2 infection in subjects of different risk groups in Spain and evaluates the diagnostic efficacy of different methodologies.

METHODS

The presence of HIV-2 antibodies was analyzed in 902 serum samples of high risk individuals collected in 1990 from: 386 drug addicts, 246 not drug addict prostitutes, 184 West Africans and 86 homo/bisexual individuals. These samples were from Barcelona, Sevilla, and Malaga. The detection of antibodies was carried out by enzymatic immunoanalysis (EIA), Western blot (WB) and an enzymoimmuno-dot (EID) designed with synthetic peptides.

RESULTS

Positive serology only for HIV-2 was detected in 7 samples from African immigrants. Two drug addicts presented double reactivity HIV-1/HIV-2 in all the tests suggesting double infection. No prostitutes or homo/bisexual males were identified with positive serology for HIV-2. Cross-reactivity between HIV-1 and HIV-2 was more frequently detected in WB than in EID. Greater discordance was found in the results obtained by EIA, WB, and EID in the West Africans than in the analysis of the samples of native subjects.

CONCLUSIONS

This study demonstrates that, for the time being, HIV-2 infection in Spain is rare although from among immigrants from endemic areas subjects with behavior to risk of transmission to the autochthonous population have been identified. The use of techniques designed with synthetic peptides may be of use to discriminate HIV-1 and HIV-2 infection in positive samples by enzymatic immunoanalysis (EIA) and Western blot which use a viral lysate as antigenic material.

[Prospective study of community-acquired pneumonias seen in a general hospital. Diagnostic errors]

BACKGROUND

The patients with community acquired pneumonias seen in an emergency service of a basic general hospital during one year were evaluated to assess their etiological, clinical and radiological features, and also to investigate the initial and final diagnosis of the disease, its evolution and the parameters associated with each microbiological type.

METHODS

A medical team investigated daily the clinical records. For etiologic diagnosis, blood cultures, serological studies, urine counterimmunoelectrophoresis (CIE) and, in individualized patients, pleural fluid culture, bronchoaspirate and bronchoalveolar lavage were performed. The discordance between the initial clinical and radiological diagnosis and the microbiological results, and also the initial and final diagnostic errors were analyzed.

RESULTS

311 cases of pneumonia (150 adults and 161 children) were diagnosed. 95 (30%) had microbiological confirmation. Streptococcus pneumoniae was the most commonly isolated organism. Serologic studies were the diagnostic method with the highest yield. Complications developed in 28% of the patients and the mortality rate was 2%. There was a relationship between mortality and a high respiratory rate on admission. The initial-final diagnostic discrepancy was 43% in atypical pneumonias and 40% in bacterial pneumonias.

CONCLUSIONS

Clinical parameters permitting the differentiation between atypical and bacterial pneumonia were not found. The initial diagnostic error was 12%, consisting of false positives in all instances, and the final diagnostic error included 15% false positives and 10% false negatives. Underlying diseases have a influence on the evolution of pneumonia. The mean respiratory rate on admission should be measured as a prognostic indicator. In the present study, urine CIE was a poorly sensitive method.

[Prevalence of type 1 human immunodeficiency virus (HIV) infection in African patients residing in Catalonia]

278 black patients from West Africa, living in Maresme, a coastal area north of Barcelona were studied in order to determine the prevalence of HIV-1 infection. During the first period (1984-86), 102 patients were studied, 3 of them were positive for HIV-2, but none was positive for HIV-1. In the second period (1987-89), 176 patients were studied and 15 were positive for HIV-1. Sexual intercourse with prostitutes of low social level was the only risk factor in all of them. Nine of these 15 patients had other STD, 4 parasite infections, 5 AIDS related-syndrome and 2 AIDS. These findings alert us to the high prevalence of HIV-1 infection in this group of patients (8.5%) and call for stricter measures to enforce hygiene in the area of prostitution.

[Perirenal hematoma caused by spontaneous upper calix rupture]

We report a case of perirenal hematoma from spontaneous rupture of the upper urinary tract associated with parenchymal rupture due to a calculus lodged in the pelvic ureter. The clinical features were pain confined to the renal fossa, leukocytosis and Hct of 36%. Diagnosis was made by percutaneous punction pyelography.

A comparison of the in-vitro activity of seventeen antibiotics against Streptococcus faecalis

The in-vitro activity of seventeen antibiotics against 177 clinical strains of Streptococcus faecalis was evaluated. Ampicillin and mezlocillin were the most active beta-lactams tested (geometric mean MICs, 0.61 and 0.74 mg/l, respectively). Aminoglycosides showed poor activity and 22.6% of the strains were resistant to 2000 mg/l of streptomycin. No correlation was observed between MICs of gentamicin and streptomycin. Moderate activity was observed when testing norfloxacin and ciprofloxacin. Teicoplanin and co-trimoxazole were extremely active, showing geometric mean MICs of 0.59 and 0.08 mg/l respectively. All strains were susceptible to vancomycin and teicoplanin.