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1.
Clin Anat ; 29(2): 256-63, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26732825

RESUMO

The quadriceps femoris is traditionally described as a muscle group composed of the rectus femoris and the three vasti. However, clinical experience and investigations of anatomical specimens are not consistent with the textbook description. We have found a second tensor-like muscle between the vastus lateralis (VL) and the vastus intermedius (VI), hereafter named the tensor VI (TVI). The aim of this study was to clarify whether this intervening muscle was a variation of the VL or the VI, or a separate head of the extensor apparatus. Twenty-six cadaveric lower limbs were investigated. The architecture of the quadriceps femoris was examined with special attention to innervation and vascularization patterns. All muscle components were traced from origin to insertion and their affiliations were determined. A TVI was found in all dissections. It was supplied by independent muscular and vascular branches of the femoral nerve and lateral circumflex femoral artery. Further distally, the TVI combined with an aponeurosis merging separately into the quadriceps tendon and inserting on the medial aspect of the patella. Four morphological types of TVI were distinguished: Independent-type (11/26), VI-type (6/26), VL-type (5/26), and Common-type (4/26). This study demonstrated that the quadriceps femoris is architecturally different from previous descriptions: there is an additional muscle belly between the VI and VL, which cannot be clearly assigned to the former or the latter. Distal exposure shows that this muscle belly becomes its own aponeurosis, which continues distally as part of the quadriceps tendon.


Assuntos
Músculo Quadríceps/anatomia & histologia , Feminino , Humanos , Masculino
2.
Int J Cosmet Sci ; 38(2): 194-200, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26352930

RESUMO

OBJECTIVE: Lipsticks and lip care products may contain saturated hydrocarbons which either stem from mineral oil saturated hydrocarbons (MOSH) or are synthetic, that is polyolefin oligomeric saturated hydrocarbons (POSH). Some of these hydrocarbons are strongly accumulated and form granulomas in human tissues, which prompted Cosmetics Europe (former Colipa) to issue a recommendation for their use in lip care and oral products. From 2012 to 2014, MOSH+POSH were determined in 175 cosmetic lip products taken from the Swiss market in order to estimate their contribution to human exposure. METHODS: Mineral oil saturated hydrocarbons and POSH were extracted and analysed by GC with FID. Areas were integrated as a total as well as by mass ranges with cuts at n-C25 and n-C34 to characterize the molecular mass distribution. RESULTS: About 68% of the products contained at least 5% MOSH+POSH (total concentration). For regular users, these products would be major contributors to their MOSH+POSH exposure. About 31% of the products contained more than 32% MOSH+POSH. Their regular usage would amount in an estimated MOSH+POSH exposure exceeding the highest estimated dietary exposure. The majority of the products contained hydrocarbons with a molecular mass range which was not in line with the recommendations of Cosmetics Europe. CONCLUSIONS: Taking into account that material applied to the lips largely ends up being ingested, MOSH and POSH levels should be reduced in the majority of cosmetic lip products. As the extensive evaluation of the data available on MOSH (EFSA J., 10, 2012, 2704) did not enable the specification of limits considered as safe, the present level of dietary exposure and its evaluation as 'of potential concern' provide the relevant bench mark, which means that lip products should contain clearly less than 5% MOSH+POSH.


Assuntos
Cosméticos/análise , Hidrocarbonetos/administração & dosagem , Óleo Mineral/administração & dosagem , Cromatografia Gasosa , Humanos
3.
Arch Orthop Trauma Surg ; 129(10): 1367-74, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19562356

RESUMO

OBJECTIVES: We report early results using a second generation locking plate, non-contact bridging plate (NCB PH((R)), Zimmer Inc. Warsaw, IN, USA), for the treatment of proximal humeral fractures. The NCB PH combines conventional plating technique with polyaxial screw placement and angular stability. DESIGN: Prospective case series. SETTING: A single level-1 trauma center. PATIENTS: A total of 50 patients with proximal humeral fractures were treated from May 2004 to December 2005. INTERVENTION: Surgery was performed in open technique in all cases. MAIN OUTCOME MEASURES: Implant-related complications, clinical parameters (duration of surgery, range of motion, Constant-Murley Score, subjective patient satisfaction, complications) and radiographic evaluation [union, implant loosening, implant-related complications and avascular necrosis (AVN) of the humeral head] at 6, 12 and 24 weeks. RESULTS: All fractures available to follow-up (48 of 50) went to union within the follow-up period of 6 months. One patient was lost to follow-up, one patient died of a cause unrelated to the trauma, four patients developed AVN with cutout, one patient had implant loosening, three patients experienced cutout and one patient had an axillary nerve lesion (onset unknown). The average age- and gender-related Constant Score (n = 35) was 76. CONCLUSIONS: The NCB PH combines conventional plating technique with polyaxial screw placement and angular stability. Although the complication rate was 19%, with a reoperation rate of 12%, the early results show that the NCB PH is a safe implant for the treatment of proximal humeral fractures.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/instrumentação , Fraturas do Ombro/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Radiografia , Amplitude de Movimento Articular , Fraturas do Ombro/diagnóstico por imagem , Resultado do Tratamento
4.
Rheumatology (Oxford) ; 47(10): 1521-6, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18676991

RESUMO

OBJECTIVE: To evaluate the metric qualities of power Doppler ultrasound (PDUS) for different quantification methods and devices in the assessment of arthritis during anti-inflammatory treatment. METHODS: Twenty-four patients with active arthritis and first-time treatment with the TNF-alpha inhibitor adalimumab underwent sequential clinical, laboratory and US examination at baseline, weeks 2, 6 and 12. 2D and 3D PDUS was performed by two independent investigators. The images and movies were scored from 0 to 3 and the amount of colour pixels and voxels was calculated. In addition, the resistance index of a synovial artery was measured. Thirteen patients were examined with a second US machine. RESULTS: Treatment response was already observed at week 2 with a significant reduction of 2D (P < 0.01) and 3D scores (P < 0.001). A moderate correlation to 28-joint disease activity score was found for 3D voxel count (r(s) = 0.35, P < 0.001). Interobserver agreement was kappa or ICC >or= 0.8 for all methods except the resistance index (ICC = 0.60). Intermachine agreement was kappa = 0.57 for 2D PDUS score. CONCLUSIONS: The study demonstrates good to excellent interobserver and moderate intermachine reliability of different PDUS assessment methods in a longitudinal open-label study.


Assuntos
Artrite/diagnóstico por imagem , Artrite/tratamento farmacológico , Adalimumab , Adulto , Idoso , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados , Antirreumáticos/uso terapêutico , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Membrana Sinovial/diagnóstico por imagem , Resultado do Tratamento , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Ultrassonografia Doppler/métodos , Articulação do Punho/diagnóstico por imagem
5.
Injury ; 46(12): 2461-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26520362

RESUMO

INTRODUCTION: With a subvastus approach to the femur, the vessels that perforate the lateral intermuscular septum (LISP-vessels) must be ligated. The effect on the blood supply to the femur remains unclear. The purpose of the current study was to investigate the effect of ligation of the LISP-Vessels on the blood supply and to examine the anatomy of the LISP-vessels and the anastomoses around the femur. MATERIALS: In six human cadavers the LISP vessels were ligated by a lateral subvastus approach on one side. The contralateral side served as control group. After bilateral injection of different coloured silicon dyes into the lateral and medial circumflex femoral artery (green), deep femoral artery (red) and the superficial femoral artery (blue) dissection was performed bilaterally. The arterial perfusion on both sides was compared and the anatomy of the LISP vessels studied. RESULTS: The medullary perfusion of the femur was not altered by the ligation of the LISP vessels. It did also not lead to a decrease in periosteal vessel filling. The LISP vessels were shown to be a part of a complex and rich anastomotic network and play an important role in the perfusion of the femur and quadriceps muscle group. The ligature could be compensated for by this anastomotic network. Branches to the periosteum separate from the LISP vessels immediately after perforating the lateral intermuscular septum. The linea aspera turned out to be an important area for the femoral blood supply. DISCUSSION AND CONCLUSIONS: Exposure of the femur through a lateral subvastus approach with ligation of LISP vessels causes a certain degree of soft tissue trauma. However, by using a gentle surgical technique the periostal perfusion of the femur can be preserved by a potent anastomotic network after ligation of the LISP vessels if they are not ligated to close to the lateral intermuscular septum and the linea aspera is not unnecessarily exposed.


Assuntos
Fraturas do Fêmur/cirurgia , Fêmur/irrigação sanguínea , Fixação Interna de Fraturas/métodos , Ligadura/métodos , Cadáver , Feminino , Artéria Femoral , Fraturas do Fêmur/patologia , Fêmur/anatomia & histologia , Humanos , Artéria Ilíaca , Masculino
6.
J Chromatogr A ; 892(1-2): 407-20, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11045501

RESUMO

Progress during the last 5 years in on-line LC-GC and related techniques is reviewed. In normal-phase LC-GC, the wire interface proved to have advantages over the loop type interface. Further investigations on the solvent evaporation process in an uncoated precolumn under conditions of an early vapour exit revealed that the rules for the transfer by the retention gap techniques must be modified. For reversed-phase LC-GC, approaches with a phase transfer compete with direct evaporation. Eluents were extracted into a bed of Tenax located in a programmed-temperature vaporiser and thermally desorbed. Direct evaporation is possible when a hot vaporising chamber is used and solvent/solute separation occurs in a separate compartment, a coated precolumn possibly in combination with packed beds. As a future strategy, LC-GC transfer techniques should be adjusted to those of large volume injection and involve a single device. It is believed that on-column injection/transfer is the choice. This requires that concurrent evaporation in LC-GC is performed by the on-column interface.


Assuntos
Cromatografia Gasosa/métodos , Cromatografia Líquida de Alta Pressão/métodos
7.
J Chromatogr A ; 897(1-2): 247-58, 2000 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-11128209

RESUMO

The processes in devices imitating a vaporising injector were video-taped using perylene as a fluorescent marker for non-evaporated sample. Processes are summarised which are observed after the sample liquid passed through a cool needle and left as a band of liquid moving at high velocity (as typical for injection by fast autosamplers). This liquid is shot past the column entrance unless stopped either by a packing, e.g., wool or by suitable obstacles. Packings of low thermal mass are locally cooled to the solvent boiling point and suck in the liquid. Stopping the liquid by obstacles is more difficult because solvent vapours prevent contact of the liquid with the hot surfaces, and was reliably achieved only by the laminar liner. For the same reason, transfer onto the liner wall only occurs for higher boiling liquids.


Assuntos
Cromatografia Gasosa/métodos , Gravação de Videoteipe , Cromatografia Gasosa/instrumentação , Dimetilformamida/análise , Temperatura Alta
8.
J Chromatogr A ; 897(1-2): 237-46, 2000 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-11128208

RESUMO

The processes in devices imitating vaporising injectors were visualised and video-taped using perylene as a fluorescent marker for non-evaporated samples. The observations in the context of thermospray injection are summarised. Partial evaporation inside the needle turns the solvent into a propellant which nebulises the sample liquid at the needle exit. Evaporation in the vaporising chamber occurs from fine droplets suspended in the gas phase. Empty injector liners are best suited; packings with glass wool or obstacles in the liner, like the cup, have no significant effect on the process observed. Non-evaporated (matrix) material forms aerosol particles which may enter the column together with the vapours, but most of them are transferred to the liner wall. Since solute material may be carried along, this is a possible source of matrix effects.


Assuntos
Cromatografia Gasosa/métodos , Gravação de Videoteipe , Cromatografia Gasosa/instrumentação
9.
J Chromatogr A ; 876(1-2): 135-45, 2000 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-10823509

RESUMO

The swing system is designed for introducing large volumes of water-containing samples into a gas chromatograph. Sample evaporation and solvent-solute separation are performed in separate compartments. This widens the application range to compounds of higher volatility. Sample evaporation takes place in a hot chamber packed with Carbofrit. Solvent-solute separation is performed in a cascade of increasing powers of retention. While high boiling solutes are retained in an oven-thermostatted retaining precolumn, the more volatile components are retained by a packed bed of sorbents of increasing powers of retention situated in a programmed temperature vaporiser. For elution, the gas flow is reversed and the solutes are discharged from the heated packed bed through the retaining precolumn into the separation column.


Assuntos
Cromatografia Gasosa/métodos , Cromatografia Gasosa/instrumentação , Ácidos Graxos/análise , Ácidos Graxos/química , Nebulizadores e Vaporizadores , Padrões de Referência , Temperatura , Fatores de Tempo , Água/química
10.
J Chromatogr A ; 750(1-2): 361-8, 1996 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-8938392

RESUMO

An automated on-line method is described that involves a first LC separation on a large column, evaporation of a 6-ml fraction in an on-line solvent evaporator, a second LC separation using a different mobile phase, fractionating the components of interest and transfer to GC through the in-line vaporizer/overflow interface. The method is designed for the injection of a large amount of food extract (e.g. up to 200 mg of fat) and is applied to the analysis of mineral oil material in a linseed oil.


Assuntos
Gorduras Insaturadas na Dieta/análise , Gorduras Insaturadas/química , Óleo Mineral/química , Sistemas On-Line/instrumentação , Compostos Policíclicos/análise , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão/métodos , Ionização de Chama , Óleo de Semente do Linho/química , Solventes/química , Espectrofotometria Ultravioleta
11.
Med Sci Sports Exerc ; 31(3): 368-71, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10188739

RESUMO

PURPOSE: It was the purpose of the present study to examine the possibility of increased muscle coordination after anterior cruciate ligament (ACL) reconstruction through the wearing of a compression sleeve. METHODS: Thirty-six patients were studied who had undergone unilateral ACL reconstruction at least 12 months previously. All subjects were required to perform a 10-cm standing drop jump from an elevated platform onto a force plate, to land on one leg, and thereafter maintain a one-legged balance for 25 s. This task was repeated three times without and three times with an elastic compression sleeve worn on the reconstructed limb. For analysis, the task was partitioned into a landing phase (150 ms), an adjusting phase (10s), and a balancing phase (10s). The peak impact loadings were measured in each direction (Fx, Fy, and Fz) during landing, while force-time integrals (intFz, intFy, and intFz) and root mean square (RMS) error of these forces were calculated for the adjusting and balancing phases. The path length and RMS of the center of pressure coordinates (Ax and Ay) were obtained for the adjusting and balancing phases combined. RESULTS: Drop landings with the bandage produced significantly larger (P < 0.001) peak ground reaction forces in the vertical and anteroposterior direction, suggesting increased subject confidence in their knee. Wearing the knee bandage also enabled the patients to reduce all measured parameters in the anteroposterior direction (rmsFx, intFx, rmsAx) during both the adjusting and balancing phases (P < 0.001 ). A significant reduction in the center of pressure path length further indicated an enhanced steadiness during the one-legged stance. CONCLUSIONS: It was concluded that a compression sleeve improved the total integration of the balance control system and muscle coordination.


Assuntos
Ligamento Cruzado Anterior/cirurgia , Braquetes , Traumatismos do Joelho/cirurgia , Equilíbrio Postural , Adulto , Feminino , Humanos , Masculino , Músculo Esquelético/fisiologia , Período Pós-Operatório , Pressão , Ruptura , Análise e Desempenho de Tarefas
12.
J Agric Food Chem ; 48(7): 2868-73, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10898638

RESUMO

The presence of 4 different furan fatty acids (F-acids) was detected in 18 samples of transmethylated monovarietal extra virgin olive oil: methyl 10,13-epoxy-11,12-dimethyloctadeca-10,12-dienoate [diMeF(9,5)], methyl 12,15-epoxy-13,14-dimethyleicosa-12,14-dienoate [diMeF(11,5)] and both olefinic derivatives of diMeF(11,5) with one unsaturation on the side chains conjugated with the furan ring. Transmethylated oils were analyzed by normal phase high-performance liquid chromatography coupled on-line with capillary gas chromatography. After the gas chromatographic separation step, a more selective detection of F-acids was achieved by using a photoionization detector mounted in series with a flame ionization detector. The concentration of F-acids ranged between 50 ppb (detection limit of the method) and 2.1 ppm in the oil. The olefinic derivatives of diMeF(11,5) acids detected were not artifacts created during the sample preparation or during the chromatographic analysis.


Assuntos
Ácidos Graxos/análise , Furanos/análise , Óleos de Plantas/química , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Azeite de Oliva , Sensibilidade e Especificidade
13.
Artigo em Inglês | MEDLINE | ID: mdl-7981882

RESUMO

Specific immunotherapy as a treatment for bronchial asthma has been a controversial field. A collaborative study was designed in an attempt to further define the possible contribution of specific immunotherapy in a pediatric population. One hundred and sixty-six patients were treated with immunotherapy and 248 received no immunotherapy. The results were compared during 10 years of follow-up in both groups. There was a significant decrease in the number of acute crisis in the treated group (p < 0.05). However, no differences were seen in the number of hospital admissions or in the quality of life between the treated and untreated groups. The treated group required significantly fewer drugs (p < 0.05). Thus, it is probable that the untreated group shows the same clinical indexes as the treated group due to their increased use of medication. Specific immunotherapy represents an effective treatment that changes the natural course of allergic bronchial asthma in pediatric patients.


Assuntos
Asma/terapia , Dessensibilização Imunológica , Obstrução das Vias Respiratórias/epidemiologia , Obstrução das Vias Respiratórias/prevenção & controle , Alérgenos/uso terapêutico , Antígenos de Dermatophagoides , Asma/tratamento farmacológico , Broncodilatadores/uso terapêutico , Pré-Escolar , Terapia Combinada , Feminino , Seguimentos , Glicoproteínas/uso terapêutico , Hospitalização/estatística & dados numéricos , Humanos , Lactente , Masculino , Pólen/imunologia , Qualidade de Vida , Resultado do Tratamento
14.
J Bone Joint Surg Br ; 84(4): 614-8, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12043789

RESUMO

Current methods of measurement of proprioceptive function depend on the ability to detect passive movement (kinaesthesia) or the awareness of joint position (joint position sense, JPS). However, reports of proprioceptive function in healthy and pathological joints are quite variable, which may be due to the different methods used. We have compared the validity of several frequently used methods to quantify proprioception. Thirty healthy subjects aged between 24 and 72 years underwent five established tests of proprioception. Two tests were used for the measurement of kinaesthesia (KT1 and KT2). Three tests were used for the measurement of JPS, a passive reproduction test (JPS1), a relative reproduction test (JPS2) and a visual estimation test (JPS3). There was no correlation between the tests for kinaesthesia and JPS or between the different JPS tests. There was, however, a significant correlation between the tests for kinaesthesia (r = 0.86). We conclude therefore that a subject with a given result in one test will not automatically obtain a similar result in another test for proprioception. Since they describe different functional proprioceptive attributes, proprioceptive ability cannot be inferred from independent tests of either kinaesthesia or JPS.


Assuntos
Articulação do Joelho/anatomia & histologia , Articulação do Joelho/fisiologia , Propriocepção , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
J Chromatogr Sci ; 28(2): 61-6, 1990 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2273062

RESUMO

Coupling LC to GC alleviates sample preparation in the sense of preseparation, cleanup, or enrichment and replaces conventional methods such as column liquid chromatography, enrichment by or filtration through sample preparation tubes, preparative thin-layer chromatography, or liquid-liquid partitioning. LC is more efficient in separation power, more rapid, and allows fully automatic integration of sample preparation into GC. Advantages are discussed for selected applications. The transfer techniques, as well as some key requirements for an LC-GC instrument, are briefly summarized.


Assuntos
Cromatografia Gasosa/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Gasosa/instrumentação , Cromatografia Líquida de Alta Pressão/instrumentação
16.
Artigo em Inglês | MEDLINE | ID: mdl-23406500

RESUMO

Mineral oil hydrocarbons present in printing inks and recycled paper migrate from paper-based food packaging to foods primarily through the gas phase. Migration from two commercial products packed in recycled paperboard, i.e. muesli and egg pasta, was monitored up to the end of their shelf life (1 year) to study the influence of time, storage conditions, food packaging structure and temperature. Mineral oil saturated and aromatic hydrocarbons (MOSH and MOAH, respectively), and diisopropyl naphthalenes (DIPN) were monitored using online HPLC-GC/FID. Storage conditions were: free standing, shelved, and packed in transport boxes of corrugated board, to represent domestic, supermarket and warehouse storage, respectively. Migration to food whose packs were kept in transport boxes was the highest, especially after prolonged storage, followed by shelved and free-standing packs. Tested temperatures were representative of refrigeration, room temperature, storage in summer months and accelerated migration testing. Migration was strongly influenced by temperature: for egg pasta directly packed in paperboard, around 30 mg kg⁻¹ of MOSH migrated in 8 months at 20°C, but in only 1 week at 40°C. Muesli was contained into an internal polyethylene bag, which firstly adsorbed hydrocarbons and later released them partly towards the food. Differently, the external polypropylene bag, containing pasta and recycled paper tray, strongly limited the migration towards the atmosphere and gave rise to the highest level of food contamination. Tests at increased temperatures not only accelerated migration, but also widened the migration of hydrocarbons to higher molecular masses, highlighting thus a difficult interpretation of data from accelerated simulation.


Assuntos
Contaminação de Alimentos/análise , Embalagem de Alimentos , Hidrocarbonetos/química , Óleo Mineral/química , Papel , Reciclagem , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Cinética , Temperatura
17.
Artigo em Inglês | MEDLINE | ID: mdl-22243490

RESUMO

POSH are polyolefin oligomeric saturated hydrocarbons, such as oligomers from polyethylene or polypropylene. POSH that have migrated into foods are easily mistaken for mineral oil-saturated hydrocarbons (MOSH). In fact, both POSH and MOSH largely consist of highly isomerised branched and possibly cyclic hydrocarbons, both forming humps of unresolved components in gas chromatography. Chromatograms are reported to show typical elution patterns of POSH and help analysts distinguishing POSH from MOSH as far as possible. Since the structures of the POSH are not fundamentally different from those of the MOSH, it would be prudent to apply the evaluation of the MOSH. However, the migration is frequently beyond that for which safety has been demonstrated. This is shown for a few examples, particularly for powdered formula for babies.


Assuntos
Contaminação de Alimentos , Embalagem de Alimentos , Polienos/análise , Polietilenos/análise , Polipropilenos/análise , Cacau/química , Manipulação de Alimentos , Alimentos em Conserva/análise , Humanos , Lactente , Alimentos Infantis/análise , Fórmulas Infantis/química , Estrutura Molecular , Oryza/química , Tubérculos/química , Polienos/química , Polietilenos/química , Polipropilenos/química , Sementes/química , Solanum tuberosum/química , Propriedades de Superfície , Água/análise , Zea mays/química
18.
Artigo em Inglês | MEDLINE | ID: mdl-20967663

RESUMO

In the absence of a functional barrier, mineral oil hydrocarbons from printing inks and recycled fibres tend to migrate from paper-based food-packaging materials through the gas phase into dry food. Concentrations easily far exceed the limit derived from the acceptable daily intake (ADI) of the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Since the estimation of long-term migration into the food by testing at 40°C for 10 days is difficult, it seems preferable (and easier) to use the mineral oil content in the paperboard. Evaporation experiments showed that hydrocarbons eluted up to about n-C24 are sufficiently volatile for relevant migration into dry food: in worst-case situations, about 80% migrate into the packed food. The extraction of the paperboard was optimised to give good recovery of the relevant hydrocarbons, but to discriminate against those of high molecular mass which tend to disturb gas chromatographic analysis in on-line coupled normal phase HPLC-GC-FID. Even though some of the relevant hydrocarbons had already evaporated, the average concentration of < C24 mineral oil saturated hydrocarbons (MOSH) in the paperboard boxes of 102 products from the Swiss and Italian market was 626 mg kg⁻¹. Nearly 15% of investigated boxes still contained more than 1000 mg kg⁻¹ < C24 MOSH up to over 3000 mg kg⁻¹ (maximum = 3500 mg kg⁻¹). This amount of MOSH in the board have the potential of contaminating the packed food at a level exceeding the limit, derived from the JECFA ADI, hundreds of times.


Assuntos
Análise de Alimentos , Contaminação de Alimentos , Embalagem de Alimentos , Hidrocarbonetos Aromáticos/análise , Hidrocarbonetos/análise , Óleo Mineral/química , Cromatografia Líquida de Alta Pressão , Ionização de Chama , Temperatura Alta , Tinta , Itália , Papel , Suíça , Fatores de Tempo
19.
Artigo em Inglês | MEDLINE | ID: mdl-20730646

RESUMO

Parallel to the European Union acrylamide monitoring for the years 2007-2009, Switzerland performed its own monitoring, covering the whole range of products that significantly contain acrylamide (almost 300 samples per year), but focusing on those products that may result in high exposure. As reducing sugars are critical for potato products, these were included. No significant change, particularly improvement, was noticed, especially regarding those products for which substantial potential for improvement is known. 'Western-style' French fries continued to contain some four times more reducing sugars than 'traditional' fries, with correspondingly higher acrylamide in the finished product. The supply of raw potatoes low in reducing sugars by retail shops needs improvement, but there seemed to be insufficient willingness on a voluntary basis. A foreign producer was successful in penetrating the Swiss market with special potato chips containing up to 7000 microg kg(-1) acrylamide and only harsh measures could stop this. Three of about 61 products in the group of bakery ware showed a marked improvement. But there was also a store brand cracker that competed with a leading brand which contained 15 times more acrylamide (845 microg kg(-1)). Cereals contained 1080 microg kg(-1) acrylamide and even a warning did not prompt the producer to sell substantially better products one year later. It seems that only measures by the authorities will achieve improvements. The following seem promising: a limit for reducing sugars in prefabricates for French fries; the improved supply of raw potatoes low in sugars for roasting and frying; a legal limit for acrylamide content in potato chips; a general provision that products must not contain substantially more acrylamide than achievable by good manufacturing practice; and fryers with a temperature profile from an initial high to a lower final value.


Assuntos
Acrilamida/análise , Contaminação de Alimentos/análise , Pão/análise , Carboidratos/análise , Café/química , Grão Comestível/química , Manipulação de Alimentos/métodos , Temperatura Alta , Solanum tuberosum/química , Suíça
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