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PubMed2004

Fat-modified diets during pregnancy and lactation and serum lipids after birth.

OBJECTIVE: This study investigated the influence of modifying the maternal dietary fat on the serum lipids of infants at birth and at one year of age. METHODS: This single-blind randomized clinical trial was done on 180 4-month-pregnant women. All subjects proved to have a fat-unmodified diet through a 4-day food record dietary questionnaire. They were divided randomly into two groups. The intervention group was kept on a fat-modified diet including saturated fatty acid (SFA) < 10%, monounsaturated fatty acids: (MUFA) 10-5%, polyunsaturated fatty acid (PUFA) upto 10% and cholesterol < 300 mg/day with dietary advice for the pregnancy period. The control group was given only the latter advice. All subjects were followed up monthly. The serum lipids including total cholesterol (T.cho), triglyceride (TG), and HDL cholesterol (HDL-C) were analyzed through enzymatic methods. The level of LDL-cholesterol (LDL-C) was calculated by Friedewald formula. The comparison of mean cord and one-year-old infant serum lipids were done through unpaired T-test in two groups. RESULTS: The mean level of T.cho in the intervention and control group was (70.3+/-15.9, vs 81.4+/-17.2, P< 0.009), TG (85.3 +/- 16.7 vs 97.5 +/- 18.2, P< 0.007), LDL-C (27.8 +/- 15.2 vs 34.8 +/- 17.1, P< 0.04) and non-HDL-C (44.5+/-7.2 vs 54.5 +/- 8.1, P< 0.02) and in one year old infant the comparison of serum lipids were as follows. T.cho (145.7 +/- 51.4 vs 161.4 +/- 56.2, P< 0.003), TG (90.1 +/- 31.8 vs 98.3 +/- 33.1, P< 0.02), LDL-C (85.6 +/- 20.4 vs 92.3 +/- 19.6, P< 0,05) and non-HDL-C (113.6 +/- 30.2 vs 128.8 +/- 34.8, P< 0.04). However, there was no significant difference in HDL-C of both groups. CONCLUSION: There is a significant decrease of T.cho, TG, LDL-C and non-HDL-C levels with no significant increase of HDL-C in the intervention group with the fat-modified diet. Maternal fat-modified diet could be suitable way to prevent cardiovascular disease among infants from the beginning of the life.

Adolescent↗
PubMed1993

The catalytic stripping voltammetry of trace copper (II) at a chemically modified electrode on oxine containing carbon paste.

An oxine modified electrode is prepared on the basis of carbon paste. The process is rapid and simple. The catalytic stripping voltammetric characteristic of Cu(II) on the modified electrode was studied and the method has been applied to the determination of trace Cu(II), and there was good linear relationship between the concentration of Cu(II) and the peak height in the concentration range of 1.5 x 10(-)-1.5 x 10(-6) mol/L for Cu(II). We have detected the copper content of human hair and blood with satisfactory results. Moreover, the reaction mechanism of the modified electrode was discussed. It was found that the improvement of sensitivity and selection of the modified electrode was dependent of the complex adsorbing property of the electrode surface and the sensitive catalytic hydrogen wave produce.

Carbon↗
PubMed1998

An evaluation of a modified Macintosh laryngoscope in a manikin.

PURPOSE: In this manikin study a modified Macintosh blade was prospectively compared with its original focussing on the forces exerted on the maxillary incisor teeth and intubation success. The modified blade, a standard Macintosh blade with a reduced proximal flange, was intended to reduce the forces exerted on the maxillary incisors. METHODS: A manikin equipped with two sensors, to measure forces applied to the maxillary incisors in the axial and the transverse direction, was used. Fourteen staff anaesthetists and 16 residents each performed two laryngoscopies with both blades. RESULTS: All laryngoscopies resulted in successful tracheal intubation. The maximal and mean forces exerted on the teeth in the axial direction were 12 N and 5.8 N smaller (P < 0.0005 and P < 0.0005, respectively) when the modified blade was used. CONCLUSION: The use of the modified blade resulted in a reduction of the forces on the maxillary incisors whereas the intubation success rate was the same as with the original. Studies in manikins can be useful in comparative laryngoscope testing.

Humans↗
PubMed2002

Alprazolam, a benzodiazepine, does not modify the ACTH and cortisol response to hCRH and AVP, but blunts the cortisol response to ACTH in humans.

Alprazolam (AL), a benzodiazepine which activates gamma-amino butyrric acid (GABA)-ergic receptors, exerts a clear inhibitory effect on the activity of the hypothalamo-pituitary-adrenal (HPA) axis and is able to markedly reduce the ACTH response to metyrapone-induced inhibition of glucocorticoid feedback. It has been suggested that its inhibitory action could be regulated by CRH or AVP mediated mechanisms. However, the effect of benzodiazepines on the HPA response to CRH or AVP is contradictory. It has been shown that benzodiazepines have specific receptors on the adrenal gland but it is unclear if they mediate biological effects in humans. In order to further clarify the mechanisms underlying the inhibitory effect of benzodiazepine on HPA axis in humans, we studied the effect of AL (0.02 mg/kg po at -90 min) or placebo in 7 healthy young volunteers (7 female, age: 26-34 yr; wt: 50-58 kg, BMI 20-22 kg/m2) on: 1) the ACTH and cortisol responses to hCRH (2.0 microg/kg iv at 0 min) or AVP (0.17 U/kg im at 0 min); 2) the cortisol, aldosterone and DHEA responses to ACTH 1-24 (0.06 and 250 microg iv at 0 and 60 min, respectively). After placebo, the ACTH and cortisol responses to hCRH (peaks, mean+/-SE: 29.8+/-4.4 pg/ml and 199.3+/-19.6 microg/l) were similar to those recorded after AVP (31.7+/-6.5 pg/ml and 164.8+/-18.0 microg/l); the cortisol response to 0.06 microg ACTH (190.4+/-11.8 microg/l) was similar to that recorded after hCRH and AVP but lower (p<0.01) than that after 250 microg ACTH (260.6+/-17.4 microg/l). AL did not modify the ACTH response to both hCRH (42.5+/-7.1 pg/ml) and AVP (33.3+/-2.7 pg/ml), which even showed a trend toward increase. AL also failed to significantly modify the cortisol response to both hCRH (156.3+/-12.7 microg/l) and AVP (119.4+/-14.5 microg/l), which, on the other hand, showed a trend toward decrease. The cortisol peaks after 0.06 microg ACTH were significantly reduced (p<0.02) by AL pre-treatment (115.0+/-7.7 microg/l) which, in turn, did not modify the cortisol response to the subsequent ACTH bolus (214.7+/-16.6 microg/l). The DHEA and aldosterone responses to all the ACTH doses were not significantly modified by AL. In conclusion, these data show that the HPA response to AVP as well as to hCRH is refractory to the inhibitory effect of AL which, in turn, blunts the cortisol response to low ACTH dose. These findings suggest that both CRH- and AVP-mediated mechanisms could underlie the CNS-mediated inhibitory effect of AL on HPA axis; in the meantime, these results suggest that benzodiazepines could also act on adrenal gland by blunting the sensitivity of the fasciculata zone to ACTH.

Adrenocorticotropic Hormone↗
PubMed2001

Comparison of modified Teuscher and van Beek functional appliance therapies in high-angle cases.

The aim of this study was to investigate the effects of modified Teuscher and van Beek functional appliances on the skeletal and dento-alveolar pattern in high-angle Class II, Division 1 patients. The collective consisted of 32 patients with a high-angle Class II, Division 1 malocclusion. The modified Teuscher activator was applied to a group of twelve patients, and the van Beek activator to a group of ten patients. A control group of ten subjects was used for comparison purposes. The mean chronological ages of the groups were 12, 11.8 and 11.5 years, respectively. 64 cephalograms taken before and after the treatment were evaluated. Intra-group measurement relations were determined by the Wilcoxon test, and inter-group relations by analysis of variance and Duncan tests, using SPSS statistical software. The following results were observed for both treated groups without any change in growth direction: inhibition of maxillary growth, stimulation of mandibular growth, retrusion of upper incisors, distal tipping of upper molars, and reduction of overjet and overbite compared with the control group. The decrease in overbite in the van Beek group was due mainly to intrusion of the incisors, and in the modified Teuscher group to molar extrusion. Both activators were considered preferable in terms of vertical control of the facial height in high-angle cases with deep overbite. However, stimulation of mandibular growth in the modified Teuscher activator group was found to be more significant than in the van Beek activator group.

Cephalometry↗
PubMed2002

TGF-beta(1) gene modified immature dendritic cells exhibit enhanced tolerogenicity but induce allograft fibrosis in vivo.

Administration of donor-derived immature dendritic cells (DC) can prolong the survival of MHC-mismatched cardiac allografts. Genetic modification of DC by immunosuppressive molecules can enhance their potential tolerogenicity. In this study bone marrow derived immature DC were genetically modified by transforming growth factor (TGF) beta1 by recombinant Ad. TGF-beta(1) gene modified immature DC (TGF-beta-DC) displayed a characteristic phenotype of immature DC, decreased ability to secrete interleukin 12, and reduced allostimulatory ability. TGF-beta-DC induced alloantigen-specific T cell hyporesponsiveness in vitro and in vivo, and Th2 cytokine polarization. mRNA expression of donor MHC class II (Ia(b)) and human TGF-beta(1) was detected in spleen and lymph nodes of the allogeneic recipients for 3 weeks after TGF-beta-DC infusion, indicating that microchimerism of TGF-beta-DC is exhibited in allogeneic recipients. In this murine cervical heterotopic heart transplantation model, the survival of the allograft in recipients intravenously infused with TGF-beta-DC 7 days before transplantation was greatly prolonged, and about 67% of cardiac grafts survived more than 40 days. Histological analysis of the allografts showed that the normal myocardial architecture was well preserved, accompanied by very little necrotic cells, but interstitial fibrosis replaced myocytes, and moderate collagen suffused the whole cardiac allograft in the recipients infused with TGF-beta-DC. mRNA expression of type III procollagen was markedly increased in the allografts of the recipients infused with TGF-beta-DC. Our results suggest that infusion of TGF-beta(1) gene modified immature DC prolongs the survival of the allograft through the effective induction of donor-specific T cell hyporesponsiveness. However, TGF-beta(1) expressed by gene modified immature DC can cause the fibrosis of the allografts, which may limit the application of this approach in the allograft transplantation.

Animals↗
PubMed2006

Modified Prusik knot versus whipstitch technique for soft tissue fixation in anterior cruciate ligament reconstruction: a biomechanical analysis.

Appropriate graft tension and secure graft incorporation in bone tunnels are essential for successful anterior cruciate ligament (ACL) reconstruction using hamstring tendon autografts. Permanent viscoplastic elongation in response to cyclic loading in the early postoperative period and the interposition of suture material in the tendon-bone interface might negatively affect graft function and rigid graft incorporation in the bone tunnels. A modified Prusik knot is an alternative option to the commonly used whipstitch technique for soft tissue fixation in ACL reconstruction. This is a controlled laboratory study. Sixteen formalin-fixed human cadaver semitendinosus tendons were armed with a modified Prusik knot or a whipstitch and tested in a load-to-failure test with a constant displacement rate of 1 mm/s, 14 in the cyclic loading test with 100 cycles from 10 to 50 N followed by 100 cycles from 10 to 75 N. The modified Prusik knot showed smaller force-induced displacements and higher stiffness of the entire construct in the load-to-failure test. Smaller preconditioning displacements were the only significant differences in the cyclic loading test. The modified Prusik knot has equal or superior mechanical properties and provides a larger area in the tendon-bone interface without suture material compared with the whipstitch technique.

Anterior Cruciate Ligament↗
PubMed2001

Clinical and gait-analytical results of the modified Evans tenodesis in chronic fibulotalar ligament instability.

The present paper describes the medium-term results (mean follow-up period 3.01 years) achieved after surgical stabilisation of 79 patients using modified Evans tenodesis. The follow-up examination included a questionnaire for rating the subjective sense of stability, a clinical examination, stress X-rays, a modified 100-point score according to Zwipp, and kinetic gait analysis. Although joint instability was significantly improved in the radiological stress images, only 73.4% of the patients subjectively rated the stability achieved as excellent or good, compared with satisfactory in 22%, and even poor in 3.8%. In the overall result of the 100-point score, 51.9% of the patients achieved a very good, 35.4% a good, 11.4% a satisfactory, and 1.3% a poor result. Radiologically, an increase in the rate of arthrosis was verified in 17.4%. Significant deteriorations in mobility were observed for the supination. The kinetic gait analysis revealed statistically significant differences compared with the non-operated side for step length (P < 0.05), relative step length (P < 0.05), and in the symmetry of heel-to-toe movement (P < 0.005). The modified Evans repair can restore the mechanical stability of the ankle, but it leads to impaired kinematics of the ankle, with subjective and functional restrictions and radiologically detectable degenerative changes. For this reason, modified Evans tenodesis should only be performed if anatomically orientated stabilisation operations are not possible.

Adolescent↗
PubMed2002

Electrocatalytic amperometric determination of amitrole using a cobalt-phthalocyanine-modified carbon paste electrode.

Cobalt-phthalocyanine-modified carbon paste electrodes are shown to be excellent indicators for electrocatalytic amperometric measurements of triazolic herbicides such as amitrole, at low oxidation potentials (+0.40 V). The detection and determination of amitrole in flow injection analysis with a modified carbon paste electrode with Co-phthalocyanine is described. The concentrations of amitrole in 0.1 M NaOH solutions were determined using the electrocatalytic oxidation signal corresponding to the Co(II)/Co(III) redox process. A detection limit of 0.04 microg mL(-1) (4 ng amitrole) was obtained for a sample loop of 100 microL at a fixed potential of +0.55 V (vs. Ag/AgCl) in 0.1 M NaOH and a flow rate of 4.0 mL min(-1). Furthermore, the modified carbon paste electrodes offers reproducible responses in such a system, and the relative standard deviation was 3.3% using the same surface, 5.1% using different surface, and 6.9% using different pastes. The performance of the cobalt-phthalocyanine-modified carbon paste electrodes is illustrated here for the determination of amitrole in commercial formulations. The response of the electrodes is stable, with more than 80% of the initial retained activity after 50 min of continuous use.

Amitrole↗
PubMed2003

Simultaneous determination of 2-nitrophenol and 4-nitrophenol based on the multi-wall carbon nanotubes Nafion-modified electrode.

In this work, multi-wall carbon nanotubes (MWNT) were conveniently dispersed into Nafion-ethanol solution, and the MWNT-Nafion-modified glassy carbon electrode (GCE) was described for the simultaneous determination of 2-nitrophenol and 4-nitrophenol. At pH 4.0 phosphate buffer, the reduction peak currents of 2-nitrophenol (at -0.8 V) and 4-nitrophenol (at -1.0 V) increase significantly at the MWNT-Nafion-modified GCE, in comparison with that at the Nafion-modified GCE and the bare GCE. The experimental parameters, such as solution pH of phosphate buffer, accumulation potential and time, and the amounts of MWNT-Nafion onto the GCE surface, were optimized. The reduction peak currents are linear with the concentration of 2-nitrophenol from 5 x 10(-8) to 1 x 10(-5) mol L(-1) and with that of 4-nitrophenol from 1 x 10(-7) to 1 x 10(-5) mol L(-1). The detection limits after 3-min accumulation are 1 x 10(-8) mol L(-1) for 2-nitrophenol and for 4 x 10(-8) mol L(-1) for 4-nitrophenol. This modified electrode was applied to direct determination of 2-nitrophenol and 4-nitrophenol in lake water samples.

Journal Article↗
PubMed2003

Direct electrochemistry of DNA, guanine and adenine at a nanostructured film-modified electrode.

A nanostructured film electrode, a multi-wall carbon nanotubes (MWNT)-modified glassy carbon electrode (GCE), is described for the simultaneous determination of guanine and adenine. The properties of the MWNT-modified GCE were investigated by scanning electron microscopy (SEM) and cyclic voltammetry. The oxidation peak currents of guanine and adenine increased significantly at the MWNT-modified GCE in contrast to those at the bare GCE. The experimental parameters were optimized and a direct electrochemical method for the simultaneous determination of guanine and adenine was proposed. Using the MWNT-modified GCE, a sensitive and direct electrochemical technique for the measurement of native DNA was also developed, and the value of (G+C)/(A+T) of HCl-digested DNA was detected.

Adenine↗
PubMed2004

Direct determination of arsenic and antimony in naphtha by electrothermal atomic absorption spectrometry with microemulsion sample introduction and iridium permanent modifier.

This paper reports the determination of arsenic and antimony in naphtha by employing electrothermal atomic absorption spectrometry (ETAAS) as the analytical technique. In order to promote the direct determination of the analytes in the very volatile naphtha, the formation of a microemulsion with different surfactants (Triton X-100 and Brij-35) and different chemical modification strategies were tested. The results indicated that Triton X-100 is the best emulsification agent for naphtha in both As and Sb determination when it is employed at a concentration of 1% w/v in the microemulsion. Under these conditions, the microemulsion was stabile for at least 2 h. By using Brij-35 it was possible to achieve good stability only in the first 15 min. Among all chemical modification approaches investigated (Ir permanent modifier, W-Ir permanent modifier, and Pd modifier), the Ir permanent modifier provided better sensitivity for both analytes and allowed a higher pyrolysis temperature, which decreased the background signals at lower levels. Under the best conditions established in this work, an RSD of 4.6% (20 microg L(-1)) and a detection limit of 2.7 microg L(-1) were observed for arsenic. For antimony, an RSD of 4.0% (20 microg L(-1)) and a detection limit of 2.5 microg L(-1) were obtained. The accuracy of the procedure was assessed by analyzing spiked samples of naphtha from different origins.

Journal Article↗
PubMed2005

Glutaraldehyde-modified electrode for nonlabeling voltammetric detection of p16 INK4A gene.

A nonlabeling electrochemical detection method for analyzing the polymerase-chain-reaction-amplified sequence-specific p16 ( INK4A ) gene, in which the basis for the covalent immobilization of deoxyribonucleic acid (DNA) probe is described, has been developed. The self-assembly process was based on the covalent coupling of glutaraldehyde (GA) as an arm molecule onto an amino-functional surface. The p16 ( INK4A ) gene was used as the model target for the methylation detection of early cancer diagnosis. An amino-modified DNA probe was successfully assembled on the GA-coupling surface through the formation of Schiff base under potential control. The hybridization of amino-modified DNA probes with the target was investigated by means of electrochemical measurements, including cyclic voltammetry and square wave voltammetry. Furthermore, the functions of GA coupling for sequence-specific detection were compared with those obtained based on mercaptopropionic acid. Hybridization experiments indicated that the covalent coupling of GA was suitable for the immobilization of DNA probe and was sensitive to the electrochemical detection of single-base mismatches of label-free DNA targets in hybridization. Moreover, reported probe-modified surfaces exhibited excellent stability, and the hybridization reactions were found to be completely reversible and highly specific for recognition in subsequent hybridization processes. The strategy provided the potential for taking full advantage of existing modified electrode technologies and was verified in microarray technology, which could be applied as a useful and powerful tool in electrochemical biosensor and microarray technology.

Base Pair Mismatch↗
PubMed2006

Analysis of the modification site in a small molecule-modified peptide by ion trap/time-of-flight hybrid mass spectrometry.

Ion trap/time-of-flight hybrid mass spectrometers are powerful tools for the detailed structural analysis of modified peptides. We have analyzed Met-Lys-bradykinin modified with deoxycholate at the amino-terminus or the epsilon-amino group as model peptides. These two modified peptides produced fragment ions with the same nominal but different exact masses in tandem mass spectrometry with low-energy collision-induced dissociation. Accurate high-resolution analysis coupled with MS(3) allowed us to distinguish the deoxycholate modification sites in the modified peptides.

Binding Sites↗
PubMed2000

Voltammetric determination of mifepristone at a DNA-modified carbon paste electrode.

A new strategy for the preparation of a DNA-modified carbon paste electrode is developed. It is found that the anodic response of mifepristone is greatly enhanced at the dsDNA-modified carbon paste electrode comparing with that obtained at the bare electrode, while the response at a ssDNA-modified electrode is similar to bare electrode. So the dsDNA-modified electrode is employed as a sensitive biosensor for the detection of mifepristone. A linear dependence of the peak currents on the concentration is observed in the range 2.0 x 10(-7) approximately 2.0 x 10(6) mol/L, with a detection limit of 1.0 x 10(-7) mol/L. The relative standard deviation is 4.3% for six successive determinations of 1.0 x 10(6) mol/L mifepristone. The determination of mifepristone tablets is carried out and satisfactory results are obtained.

Biosensing Techniques↗
PubMed2000

Application of a modified simplex method to the multivariable optimization of a new FIA system for the determination of osmium.

A methodology based on the coupling of experimental design and a modified simplex method is proposed for the optimization of a new flow injection-kinetic system for the spectrophotometric determination of Os (IV) with m-acetylchlorophosphonazo, which has for the first time been used as chromogenic reagent in the quantitative analysis of this element. An orthogonal array design is utilized to design the experimental protocol, in which six variables are varied simultaneously, and obtain the initial simplex using 25 experiments. A modified simplex method is applied to continuously optimize the data of the orthogonal array design; the search for optimum conditions of 6 variables using the modified simplex method required only 25 experiments. The efficiency and simplicity of the coupling of the experimental design and the modified simplex method are attractive for the development of new analytical methods. The method has been applied to the determination of Os (IV) in a refined ore as well as in a secondary alloy and provided satisfactory results.

Journal Article↗
PubMed2007

Monoclonal antibody 2C5-modified doxorubicin-loaded liposomes with significantly enhanced therapeutic activity against intracranial human brain U-87 MG tumor xenografts in nude mice.

Liposomes, modified with monoclonal antibodies, are suitable carriers for targeted delivery of chemotherapeutic drugs into brain tumors. Here, we investigate the therapeutic efficacy of monoclonal anticancer antibody 2C5-modified long-circulating liposomes (LCL) loaded with doxorubicin (2C5-DoxLCL) for the treatment of U-87 MG human brain tumors in an intracranial model in nude mice. In vitro, 2C5-DoxLCL is significantly more effective in killing the U-87 MG tumor cells than Doxil (commercial doxorubicin-loaded PEGylated LCL) or DoxLCL modified with a non-specific IgG. 2C5-immunoliposomes also demonstrate a significantly higher accumulation in U-87 MG tumors compared to all controls in a subcutaneous model. The treatment of intracranial U-87 MG brain tumors in nude mice with 2C5-DoxLCL provides a significant therapeutic benefit over control formulations, substantially reducing the tumor size and almost doubling the survival time. Thus, monoclonal antibody 2C5-modified LCL can specifically target the anticancer drugs to brain tumors, leading to improved therapeutic treatment of brain tumor in an intracranial model, in vivo.

Animals↗
PubMed1998

Human tumor cells, modified by a novel pressure/crosslinking methodology, promote autologous lymphocyte proliferation and modulate cytokine secretion.

Hydrostatic pressure (P) combined with membrane protein crosslinking (CL) by adenosine dialdehyde (AdA) can render tumor cells immunogenic. We have recently shown that PCL treatment of murine tumor cells augmented the presentation of MHC-restricted tumor-associated antigens and enhanced cell-mediated immunity. In cancer patients inoculated with autologous PCL-modified tumor cells, a significant delayed-type hypersensitivity response was elicited. Since the balance between cell-mediated immunity and humoral immunity is reciprocally controlled by immunoregulatory cytokines, we have examined the proliferative response and cytokine secretion pattern in cultures of human peripheral blood mononuclear cells (PBMC) stimulated by autologous PCL-modified and unmodified tumor cells. These tumor cells were obtained from freshly resected tumor tissue of 16 patients with colon (8), lung (4) and renal (4) carcinomas. The results demonstrated that PCL-modified tumor cells promoted an increase in PBMC proliferation in 5 out of 8 (63%), 1 out of 4 (25%) and 4 out of 4 (100%) colon, lung and renal cell carcinomas. Fourteen of the above cultures were also analyzed for the secretion of interleukin-10 and interferon-gamma. Overall, a substantial decrease in IL-10 secretion was detected in 9 out of 14 (64%) cultures while a reciprocal increase in interferon-gamma secretion was noted in 8 out of 14 (57%) cultures. Our results confirmed that PCL-modified human tumor cells of different etiologies can modulate the pattern of cytokines released from stimulated autologous lymphocytes. Such a procedure could prove valuable in the production of autologous tumor vaccines.

Carcinoma↗