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1.
Eur Rev Med Pharmacol Sci ; 27(5): 1722-1728, 2023 03.
Article in English | MEDLINE | ID: mdl-36930468

ABSTRACT

OBJECTIVE: The aim of this study is to evaluate the effect of ten proinflammatory cytokines in GCF of participants with raised body mass index (BMI) compared to non-obese subjects undergoing fixed orthodontic treatment. PATIENTS AND METHODS: In the cross-sectional cohort, subjects were shortlisted through the purposive sampling method with the same age and gender and similar characteristics (cohort). For inclusion and exclusion, predefined criteria were followed. In all included participants obese and non-obese collection of GCF was made from mandibular canine to canine. Identification of inflammatory mediators (MPO and CRP) leptin, adiponectin, and resistin (pg/mL). Bone remodeling biomarkers RANKL (pg/mL) and tissue remodeling biomarkers MMP8, MMP9, TIMP1, and MMP8/TIMP1, MMP9/TIMP1 ratio were collected and blinded by the investigator. Normal distribution of data i.e., age, BMI, the flow rate of GCF, indices plaque and gingival, and uWMS were compared using a t-test. Non-normality biomarker data were evaluated using Mann-Whitney U-test. To assess the relationship between the concentration of GCF biomarkers and plaque and gingival indices Pearson and Spearman correlation coefficients were used. RESULTS: The total number of participants included was 44. In the obese and non-obese groups, the male/female ratio was the same i.e., (n=11 each). The mean age of participants in the obese group was (25.7±1.55 years), whereas the non-obese group was (26.1±1.29 years). In obese the mean BMI was (33.6±2.1 kg/m2) whereas in non-obese (22.9±1.9 kg/m2) (p<0.02). Among the levels of biomarkers adiponectin (p<0.006) and leptin (p<0.028) demonstrated a significant difference between obese and non-obese participants. Also, a significant difference was noted between obese and non-obese in tissue remodeling biomarker MMP9 (p<0.03). CONCLUSIONS: A surge in the level of the biomarkers, i.e., MMP9, leptin, and adiponectin in the gingival crevicular fluid is found in obese undergoing fixed orthodontic treatment.


Subject(s)
Gingival Crevicular Fluid , Leptin , Male , Female , Humans , Matrix Metalloproteinase 8 , Matrix Metalloproteinase 9 , Cross-Sectional Studies , Adiponectin , Obesity , Biomarkers/analysis
2.
Pediatr Nephrol ; 32(8): 1363-1367, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28299461

ABSTRACT

OBJECTIVE: Levamisole (LEV) has been used successfully on an alternate-day regime of 2.5 mg/kg in steroid-dependant nephrotic syndrome (SDNS) to maintain remission. This pilot study was carried out between 2010 and 2015 at a single center in Sri Lanka to evaluate the efficacy of LEV prescribed at 2.5 mg/kg daily, which is double the alternate-day dose. METHODS: Sequential children with SDNS, relapsing more than twice in the preceding 12 months and previously treated with LEV and low-dose alternate-day prednisolone (0.1-0.6 mg/kg) were recruited to the study. This group received LEV (2.5 mg/kg) daily with the same dose of alternate-day prednisolone for 1 year. Urine protein excretion was recorded by parents on a daily basis, and the presence of 3+ proteinuria on 3 consecutive days was considered a relapse. Full blood counts and liver function tests were performed every 3 months to monitor for adverse effects. RESULTS: Sixty-four children were enrolled into the study; six were excluded due to prescription of other immunosuppressive drugs. Median age was 7.9 years; 33 were boys. The number of relapse episodes was 163 [mean per patient 2.8 ± standard deviation (SD) 0.8] in patients on alternate-day LEV and 77 (mean 1.3 ± SD 0.9) for those on daily LEV during the 12-month period of observation. The P value 0.000 (according to the Wilcoxon signed-rank test) was <0.001. No major adverse events were noted. CONCLUSIONS: The prescription of daily LEV is effective and safe for maintaining SDNS remission.


Subject(s)
Adjuvants, Immunologic/therapeutic use , Immunosuppressive Agents/therapeutic use , Levamisole/therapeutic use , Nephrotic Syndrome/drug therapy , Proteinuria/drug therapy , Adjuvants, Immunologic/pharmacology , Adolescent , Child , Child, Preschool , Dose-Response Relationship, Drug , Drug Administration Schedule , Drug Therapy, Combination/methods , Female , Humans , Kidney/physiopathology , Levamisole/pharmacology , Liver Function Tests , Male , Nephrotic Syndrome/urine , Neutropenia/blood , Neutropenia/chemically induced , Neutrophils/drug effects , Pilot Projects , Prednisolone/therapeutic use , Proteinuria/urine , Recurrence , Renal Elimination , Sri Lanka , Treatment Outcome
3.
Pediatr Nephrol ; 32(8): 1377-1382, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28341877

ABSTRACT

BACKGROUND: Relapses of childhood nephrotic syndrome (NS) are frequently precipitated by viral upper respiratory tract infections (URTIs). A review of the literature reveals that in patients with steroid-dependent NS on alternate day corticosteroids, a short course of daily corticosteroid therapy during the course of an URTI may reduce relapse frequency. OBJECTIVE: To assess the effect of a short course of low-dose corticosteroid therapy during the course of an URTI on relapse frequency in patients with steroid-sensitive NS who have not been taking any treatment for a minimum period of 3 months. METHODS: A double-blind placebo-controlled crossover trial was conducted on 48 patients with idiopathic NS who had not been receiving corticosteroid therapy for a minimum of 3 months. Patients were randomized into two groups. Group A received 5 days of daily prednisolone at 0.5 mg/kg at the onset of an URTI while group B received 5 days of placebo. Both groups were followed up for 1 year and the URTI-induced relapse frequency was noted. A crossover was performed during the next year, with group A receiving placebo and group B receiving prednisolone. RESULTS: Thirty-three patients completed the study. In the treatment group, 115 episodes of URTI led to 11 relapses while in the control group 101 episodes of URTI led to 25 relapses. There was no significant difference between the mean number of URTIs between the treatment and control groups. The treatment group had significantly less relapses compared to the control group (p = 0.014). Within the treatment group, 65.6% did not relapse, while the remainder had a single relapse. In contrast, only 40.6% of the control group remained in remission while 40.6% suffered a single relapse and 18.8% had two or more relapses. CONCLUSIONS: Prescribing a short course of daily corticosteroids during an URTI significantly reduces the frequency of URTI-induced relapse in patients with steroid-responsive NS who are off corticosteroid therapy.


Subject(s)
Glucocorticoids/therapeutic use , Nephrotic Syndrome/drug therapy , Prednisolone/therapeutic use , Respiratory Tract Infections/drug therapy , Secondary Prevention/methods , Adolescent , Child , Child, Preschool , Cross-Over Studies , Double-Blind Method , Drug Administration Schedule , Female , Follow-Up Studies , Humans , Incidence , Male , Nephrotic Syndrome/complications , Nephrotic Syndrome/epidemiology , Placebos , Recurrence , Respiratory Tract Infections/complications , Respiratory Tract Infections/epidemiology , Sri Lanka/epidemiology , Treatment Outcome
4.
Eur Rev Med Pharmacol Sci ; 18(21): 3315-9, 2014.
Article in English | MEDLINE | ID: mdl-25487945

ABSTRACT

OBJECTIVE: Electronic cigarette smoking is gaining dramatic popularity and is steadily spreading among the adolescents, high income, urban population around the world. The aim of this study is to highlight the hazards of e-cigarette smoking on human health. MATERIALS AND METHODS: In this study, we identified 38 published studies through a systematic database searches including ISI-web of science and pub-med. We searched the related literature by using the key words including Electronic cigarette, E-cigarette, E-vapers, incidence, hazards. Studies in which electronic cigarette smoking hazards was investigated were included in the study. No limitations on publication status, study design of publication were implemented. Finally we included 28 publications and remaining 10 were excluded. RESULTS: E-smoking can cause, nausea, vomiting, headache, dizziness, choking, burn injuries, upper respiratory tract irritation, dry cough, dryness of the eyes and mucous membrane, release of cytokines and pro-inflammatory mediators, allergic airway inflammation, decreased exhaled nitric oxide (FeNO) synthesis in the lungs, change in bronchial gene expression and risk of lung cancer. CONCLUSIONS: Electronic cigarettes are swiftly promoted as an alternative to conventional cigarette smoking, although its use is highly controversial. Electronic cigarettes are not a smoking cessation product. Non-scientific claims about e-cigarettes are creating confusion in public perception about e-cigarette and people believe that e-cigarettes are safe and less addictive, but its use is unsafe and hazardous to human health. E-cigarette smoking should be regulated in the same way as traditional cigarettes and must be prohibited to children and adolescents.


Subject(s)
Electronic Nicotine Delivery Systems/adverse effects , Smoking/adverse effects , Adolescent , Child , Databases, Bibliographic , Humans
5.
Anal Chem ; 86(8): 3756-63, 2014 Apr 15.
Article in English | MEDLINE | ID: mdl-24650201

ABSTRACT

Mass spectrometry imaging (MSI) performed under ambient conditions is a convenient and information-rich method that allows for the comprehensive mapping of chemical species throughout biological tissues with typical spatial resolution in the 40-200 µm range. Ambient MSI methods such as desorption electrospray ionization (DESI) eliminate necessary sample preparation but suffer from lower spatial resolution than laser-based and vacuum techniques. In order to take advantage of the benefits of ambient imaging and to compensate for the somewhat limited spatial resolution, a secondary orthogonal separation nested in the imaging scheme was implemented for more selective discernment of tissue features in the spectral domain. Differential mobility spectrometry (DMS), an ion mobility-based separation that selectively transmits ions based on their high-to-low electric field mobility differences, can significantly reduce background chemical interferences, allowing for increased peak capacity. In this work, DESI DM-MSI experiments on biological tissue samples such as sea algae and mouse brain tissue sections were conducted using fixed DMS compensation voltages that selectively transferred one or a class of targeted compounds. By reducing chemical noise, the signal-to-noise ratio was improved 10-fold and the image contrast was doubled, effectively increasing image quality.


Subject(s)
Spectrometry, Mass, Electrospray Ionization/methods , Animals , Brain Chemistry , Chlorophyta/chemistry , Electromagnetic Fields , Image Processing, Computer-Assisted , Mice , Plants/chemistry , Rats , Signal Processing, Computer-Assisted , Signal-To-Noise Ratio
6.
J Am Soc Mass Spectrom ; 24(4): 646-9, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23440717

ABSTRACT

We present omniSpect, an open source web- and MATLAB-based software tool for both desorption electrospray ionization (DESI) and matrix-assisted laser desorption ionization (MALDI) mass spectrometry imaging (MSI) that performs computationally intensive functions on a remote server. These functions include converting data from a variety of file formats into a common format easily manipulated in MATLAB, transforming time-series mass spectra into mass spectrometry images based on a probe spatial raster path, and multivariate analysis. OmniSpect provides an extensible suite of tools to meet the computational requirements needed for visualizing open and proprietary format MSI data.


Subject(s)
Image Processing, Computer-Assisted/methods , Molecular Imaging/methods , Software , Spectrometry, Mass, Electrospray Ionization/methods , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Animals , Brain Chemistry , Databases, Factual , Multivariate Analysis , Rats
8.
Anal Chem ; 82(22): 9159-63, 2010 Nov 15.
Article in English | MEDLINE | ID: mdl-20968300

ABSTRACT

Desorption electrospray ionization (DESI) is rapidly becoming established as one of the most powerful ionization techniques allowing direct surface analysis by mass spectrometry (MS) in the ambient environment. DESI provides a significant number of unique analytical capabilities for a broad range of applications, both quantitative and qualitative in nature including biological tissue imaging, pharmaceutical quality control, in vivo analysis, proteomics, metabolomics, forensics, and explosives detection. Despite its growing adoption as a powerful high throughput analysis tool, DESI-MS analysis at trace levels often suffers from background chemical interferences generated during the electrospray ionization processes. In order to improve sensitivity and selectivity, a differential mobility (DM) ion separation cell was successfully interfaced to a custom-built DESI ion source. This new hybrid platform can be operated in two modes: the "DM-off" mode for standard DESI analysis and "DM-on mode" where DESI-generated ions are detected after discrimination by the differential mobility cell. The performance of the DESI-DM-MS platform was tested with several samples typically amenable to DESI analysis, including counterfeit pharmaceuticals and binary mixtures of isobaric chemicals of importance in the pharmaceutical and food industries. In the DM-on mode, DESI-MS signal-to-noise ratios were improved by 70-190% when compared to the DM-off mode. Also, the addition of the DM cell enabled selective in-source ion activation of specific DESI-generated precursor ions, providing tandem MS-like spectra in a single stage mass spectrometer.

9.
Anal Chem ; 82(6): 2178-81, 2010 Mar 15.
Article in English | MEDLINE | ID: mdl-20155978

ABSTRACT

Presented here is a novel ambient ion source termed infrared laser ablation metastable-induced chemical ionization (IR-LAMICI). IR-LAMICI integrates IR laser ablation and direct analysis in real time (DART)-type metastable-induced chemical ionization for open air mass spectrometry (MS) ionization. The ion generation in the IR-LAMICI source is a two step process. First, IR laser pulses impinge the sample surface ablating surface material. Second, a portion of ablated material reacts with the metastable reactive plume facilitating gas-phase chemical ionization of analyte molecules generating protonated or deprotonated species in positive and negative ion modes, respectively. The successful coupling of IR-laser ablation with metastable-induced chemical ionization resulted in an ambient plasma-based spatially resolved small molecule imaging platform for mass spectrometry (MS). The analytical capabilities of IR-LAMICI are explored by imaging pharmaceutical tablets, screening counterfeit drugs, and probing algal tissue surfaces for natural products. The resolution of a chemical image is determined by the crater size produced with each laser pulse but not by the size of the metastable gas jet. The detection limits for an active pharmaceutical ingredient (acetaminophen) using the IR-LAMICI source is calculated to be low picograms. Furthermore, three-dimensional computational fluid dynamic simulations showed improvements in the IR-LAMICI ion source are possible.

10.
Anal Chem ; 82(2): 621-7, 2010 Jan 15.
Article in English | MEDLINE | ID: mdl-20020764

ABSTRACT

In this paper, we demonstrate the first use of a microplasma ionization source for ambient mass spectrometry. This device is a robust, easy-to-operate microhollow discharge that enables ambient direct analysis of gaseous, liquid, and solid-phase samples with minimum requirements in terms of operating power and high purity gas consumption. The initial performance of the microplasma device has been evaluated by ionizing samples containing dimethyl sulfoxide (DMSO), dimethylformamide (DMF), methyl salicylate, caffeine, l-leucine, l-histidine, loratadine, ibuprofen, acetaminophen, acetylsalicylic acid, and cocaine in various forms. These molecules are diverse in nature, but almost all have relatively high proton affinities. Thus, the major species observed in all obtained mass spectra corresponded to protonated molecules. Though these microplasmas are known to produce significant densities of metastable species and electrons with mean energies greater than several electronvolt, minimal fragmentation was observed. Background spectra showed prominent signals corresponding to H(+)(H(2)O)(2) ions and a distinct lack of H(3)O(+). Small water cluster ions are likely the dominant proton transfer agents, giving rise to mass spectral data very similar to that obtained using other plasma-based ambient ionization techniques. The simplicity, low cost, low power, low rate of gas consumption, and possibility of being batch-fabricated, makes these microplasma devices attractive candidates as ion sources for miniaturized mass spectrometry and other field detection applications.

11.
Article in English | MEDLINE | ID: mdl-19963935

ABSTRACT

Traditional imaging techniques for studying the spatial distribution of biological molecules such as proteins, metabolites, and lipids, require the a priori selection of a handful of target molecules. Imaging mass spectrometry provides a means to analyze thousands of molecules at a time within a tissue sample, adding spatial detail to proteomic, metabolomic, and lipidomic studies. Compared to traditional microscopic images, mass spectrometric images have reduced spatial resolution and require a destructive acquisition process. In order to increase spatial detail, we propose a constrained acquisition path and signal degradation model enabling the use of a general image deblurring algorithm. Our analysis shows the potential of this approach and supports prior observations that the effect of the sprayer focuses on a central region much smaller than the extent of the spray.


Subject(s)
Molecular Imaging/methods , Spectrometry, Mass, Electrospray Ionization/methods , Antimalarials/analysis , Artemisinins/analysis , Artesunate , Tablets
12.
Anal Chem ; 81(18): 7788-94, 2009 Sep 15.
Article in English | MEDLINE | ID: mdl-19689156

ABSTRACT

Presented here is a novel multimode ambient ion source termed desorption electrospray/metastable-induced ionization (DEMI), which integrates the benefits and circumvents some of the limitations of desorption electrospray ionization (DESI, polarity range limited) and direct analysis in real time (DART)-type metastable-induced chemical ionization (MICI, molecular weight limited). This ion source allows three unique operation modes, each with unique capabilities, including spray (DESI-like)-only, MICI-only, and DEMI (multimode), and can be thus operated in each of these modes allowing the detection of a wider range of analytes of interest. Ion source operation in the MICI-only mode is particularly well suited for the analysis of low-polarity, low-molecular weight compounds in powdered, solid, or dissolved samples. Operation of the ion source in spray-only mode shows superior performance for the analysis of high-molecular weight, high-polarity compounds over the MICI-only mode. Heating the nebulizer gas in spray-only mode allows improved analyte solubility in the spray solvent, enabling up to an order of magnitude improvement in sensitivity. Perhaps the most appealing mode of operation of the ion source is the DEMI mode which allows the simultaneous detection of compounds within a much broader range of polarities and molecular weights than each of the individual modes. For drug quality screening and counterfeit detection applications, operation in the DEMI mode results in the generation of both protonated and sodiated analytes. The observation of such complementary ionic species facilitates compound identification when investigating unknowns.

13.
Chem Commun (Camb) ; (31): 4699-701, 2009 Aug 21.
Article in English | MEDLINE | ID: mdl-19641814

ABSTRACT

A new low activity (63)Ni ionization technique, beta electron-assisted direct chemical ionization (BADCI) is reported and applied to the analysis of active ingredients in solid pharmaceutical tablets without sample preparation.

14.
Anal Chem ; 81(12): 4803-12, 2009 Jun 15.
Article in English | MEDLINE | ID: mdl-19453162

ABSTRACT

During the past decade, there has been a marked increase in the number of reported cases involving counterfeit medicines in developing and developed countries. Particularly, artesunate-based antimalarial drugs have been targeted, because of their high demand and cost. Counterfeit antimalarials can cause death and can contribute to the growing problem of drug resistance, particularly in southeast Asia. In this study, the complementarity of two-dimensional diffusion-ordered (1)H nuclear magnetic resonance spectroscopy (2D DOSY (1)H NMR) with direct analysis in real-time mass spectrometry (DART MS) and desorption electrospray ionization mass spectrometry (DESI MS) was assessed for pharmaceutical forensic purposes. Fourteen different artesunate tablets, representative of what can be purchased from informal sources in southeast Asia, were investigated with these techniques. The expected active pharmaceutical ingredient was detected in only five formulations via both nuclear magnetic resonance (NMR) and mass spectrometry (MS) methods. Common organic excipients such as sucrose, lactose, stearate, dextrin, and starch were also detected. The graphical representation of DOSY (1)H NMR results proved very useful for establishing similarities among groups of samples, enabling counterfeit drug "chemotyping". In addition to bulk- and surface-average analyses, spatially resolved information on the surface composition of counterfeit and genuine antimalarial formulations was obtained using DESI MS that was performed in the imaging mode, which enabled one to visualize the homogeneity of both genuine and counterfeit drug samples. Overall, this study suggests that 2D DOSY (1)H NMR, combined with ambient MS, comprises a powerful suite of instrumental analysis methodologies for the integral characterization of counterfeit antimalarials.


Subject(s)
Antimalarials/analysis , Magnetic Resonance Spectroscopy/methods , Spectrometry, Mass, Electrospray Ionization/methods , Drug Compounding , Magnetic Resonance Spectroscopy/instrumentation , Spectrometry, Mass, Electrospray Ionization/instrumentation , Tablets/chemistry
15.
Proc Natl Acad Sci U S A ; 106(18): 7314-9, 2009 May 05.
Article in English | MEDLINE | ID: mdl-19366672

ABSTRACT

Organism surfaces represent signaling sites for attraction of allies and defense against enemies. However, our understanding of these signals has been impeded by methodological limitations that have precluded direct fine-scale evaluation of compounds on native surfaces. Here, we asked whether natural products from the red macroalga Callophycus serratus act in surface-mediated defense against pathogenic microbes. Bromophycolides and callophycoic acids from algal extracts inhibited growth of Lindra thalassiae, a marine fungal pathogen, and represent the largest group of algal antifungal chemical defenses reported to date. Desorption electrospray ionization mass spectrometry (DESI-MS) imaging revealed that surface-associated bromophycolides were found exclusively in association with distinct surface patches at concentrations sufficient for fungal inhibition; DESI-MS also indicated the presence of bromophycolides within internal algal tissue. This is among the first examples of natural product imaging on biological surfaces, suggesting the importance of secondary metabolites in localized ecological interactions, and illustrating the potential of DESI-MS in understanding chemically-mediated biological processes.


Subject(s)
Antifungal Agents/analysis , Seaweed/chemistry , Spectrometry, Mass, Electrospray Ionization/methods , Antifungal Agents/pharmacology , Ascomycota/drug effects
16.
Anal Chem ; 81(4): 1347-56, 2009 Feb 15.
Article in English | MEDLINE | ID: mdl-19140748

ABSTRACT

In recent years mass spectrometry based techniques have emerged as structural biology tools for the characterization of macromolecular, noncovalent assemblies. Many of these efforts involve preservation of intact protein complexes within the mass spectrometer, providing molecular weight measurements that allow the determination of subunit stoichiometry and real-time monitoring of protein interactions. Attempts have been made to further elucidate subunit architecture through the dissociation of subunits from the intact complex by colliding it into inert gas atoms such as argon or xenon. Unfortunately, the amount of structural information that can be derived from such strategies is limited by the nearly ubiquitous ejection of a single, unfolded subunit. Here, we present results from the gas-phase dissociation of protein-protein complexes upon collision into a surface. Dissociation of a series of tetrameric and pentameric proteins demonstrate that alternative subunit fragments, not observed through multiple collisions with gas atoms, can be generated through surface collision. Evidence is presented for the retention of individual subunit structure, and in some cases, retention of noncovalent interactions between subunits and ligands. We attribute these differences to the rapid large energy input of ion-surface collisions, which leads to the dissociation of subunits prior to the unfolding of individual monomers.


Subject(s)
Protein Multimerization , Proteins/chemistry , Argon/chemistry , C-Reactive Protein/chemistry , C-Reactive Protein/metabolism , Hemoglobins/chemistry , Hemoglobins/metabolism , Humans , Mass Spectrometry , Prealbumin/chemistry , Prealbumin/metabolism , Protein Denaturation , Protein Folding , Protein Structure, Quaternary , Proteins/metabolism , Surface Properties
17.
J Am Soc Mass Spectrom ; 19(7): 903-13, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18598898

ABSTRACT

The ability to preserve noncovalent, macromolecular assemblies intact in the gas phase has paved the way for mass spectrometry to characterize ions of increasing size and become a powerful tool in the field of structural biology. Tandem mass spectrometry experiments have the potential to expand the capabilities of this technique through the gas-phase dissociation of macromolecular complexes, but collisions with small gas atoms currently provide very limited fragmentation. One alternative for dissociating large ions is to collide them into a surface, a more massive target. Here, we demonstrate the ability and benefit of fragmenting large protein complexes and inorganic salt clusters by surface-induced dissociation (SID), which provides more extensive fragmentation of these systems and shows promise as an activation method for ions of increasing size.


Subject(s)
Multiprotein Complexes/chemistry , Protein Conformation , Spectrometry, Mass, Electrospray Ionization/methods , Animals , Humans , Surface Properties
18.
Anal Chem ; 80(5): 1425-36, 2008 Mar 01.
Article in English | MEDLINE | ID: mdl-18247517

ABSTRACT

A novel in-line surface-induced dissociation (SID) device was designed and implemented in a commercial QTOF instrument (Waters/Micromass QTOF II). This new setup allows efficient SID for a broad range of molecules. It also allows direct comparison with conventional collision-induced dissociation (CID) on the same instrument, taking advantage of the characteristics of QTOF instrumentation, including extended mass range, improved sensitivity, and better resolution compared with quadrupole analyzers and ion traps. Various peptides and a noncovalent protein complex have been electrosprayed and analyzed with the new SID setup. Here we present SID of leucine enkephalin, fibrinopeptide A, melittin, insulin chain-B, and a noncovalent protein complex from wheat, heat shock protein 16.9. The SID spectra were also compared to CID spectra. With the SID setup installed, ion transmission proved to be efficient. SID fragmentation patterns of peptides are, in general, similar to CID, with differences in the relative intensities of some peaks such as immonium ions, backbone cleavage b- versus y-type ions, and y- versus y-NH3 ions, suggesting enhanced accessibility to high-energy/secondary fragmentation channels with SID. Furthermore, these results demonstrate that the in-line SID setup is a valid substitute for CID, with potential advantages for activation of singly/multiply charged peptides and larger species such as noncovalent protein complexes.


Subject(s)
Mass Spectrometry/instrumentation , Multiprotein Complexes/chemistry , Peptides/chemistry , Animals , Cattle , Enkephalin, Leucine/chemistry , Fibrinopeptide A/chemistry , Insulin/chemistry , Melitten/chemistry , Surface Properties
19.
Arch Dis Child ; 92(7): 585-8, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17284479

ABSTRACT

OBJECTIVE: Children with nephrotic syndrome (NS) are usually treated with long-term low dose alternate day prednisolone with or without glucocorticoid sparing therapy, such as levamisole or ciclosporin, to maintain remission. The degree of hypothalamic-pituitary-adrenal axis (HPA) suppression with such therapeutic strategies has not been studied systematically. HPA suppression could cause a relapse or adrenal crisis. STUDY DESIGN: To study the risks of HPA suppression, a modified low dose synacthen test (0.5 mug) was administered to 32 patients (22 male,10 female) with a mean age of 9.7 years (range 3.8-17.6 years) with NS receiving long-term alternate day prednisolone for over 12 months. Twelve patients received alternate day prednisolone, 11 alternate prednisolone+levamisole and nine alternate prednisolone+ciclosporin. All patients were followed up for 3 years and the relapse rate noted. RESULTS: 20/32 (62.5%) patients had a peak serum cortisol concentration of <500 nmol/l, which suggested suboptimal cortisol secretion and possible HPA suppression. 10/12 children in the prednisolone group and 8/11 in the levamisole group had a suboptimal cortisol response compared with 2/9 in the ciclosporin group. During follow-up, the 20 children who had a suboptimal cortisol response had significantly more relapses (95 relapses) compared to the 12 children with a normal cortisol response who had 24 relapses (p = 0.01). CONCLUSIONS: Children with NS receiving long-term alternate day prednisolone therapy are at risk of developing HPA suppression and should be evaluated using the modified synacthen test. Children with evidence of HPA suppression are at a greater risk of relapse.


Subject(s)
Glucocorticoids/adverse effects , Hypothalamo-Hypophyseal System/drug effects , Nephrotic Syndrome/physiopathology , Pituitary-Adrenal System/drug effects , Prednisolone/adverse effects , Adolescent , Child , Child, Preschool , Cosyntropin , Cyclosporine/therapeutic use , Drug Administration Schedule , Drug Therapy, Combination , Female , Follow-Up Studies , Glucocorticoids/administration & dosage , Glucocorticoids/therapeutic use , Humans , Hydrocortisone/blood , Hypothalamo-Hypophyseal System/physiopathology , Levamisole/therapeutic use , Male , Nephrotic Syndrome/drug therapy , Pituitary-Adrenal System/physiopathology , Prednisolone/administration & dosage , Prednisolone/therapeutic use , Recurrence
20.
Pediatr Nephrol ; 22(2): 215-21, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17146670

ABSTRACT

Clinical and histological data of children presenting with steroid-resistant nephrotic syndrome and renal biopsy showing focal and segmental glomerulosclerosis from 1980 with a follow-up of over 10 years were reviewed. There were 66 patients; 38 male and 28 female. Age at onset ranged from 0.4-14.1 years (mean 6.4). Tubular atrophy was present at first biopsy in 50/66, capsular adhesions in 35/66, glomerular tip lesions in 8/66 and mesangial expansion in 31/66 patients. In 51 children, cyclophosphamide was prescribed as the first cytotoxic agent, while 15 received cyclosporine A and complete remission was induced in 43 and 40% of the children, respectively. Complete and stable remission was maintained in 35 children, while 22 had reduction of proteinuria with symptomatic relief. Nine were refractory to cytotoxic therapy. Of the 35 patients who entered complete and stable remission, the renal survival was over 90%, while in the 31 non-responders it was 48% in 10 years. The multivariate analysis using unconditional logistic regression method identified the presence of mesangial expansion (p=0.011) and tip lesions (p=0.005) as the independent predictors of favourable response to cytotoxic therapy and the presence of renal impairment (p=0.008) and extensive focal segmental sclerosis (p=0.025) as independent predictors of unfavourable response.


Subject(s)
Glomerulosclerosis, Focal Segmental/drug therapy , Proteinuria/diagnosis , Renal Insufficiency/diagnosis , Adolescent , Child , Child, Preschool , Female , Glomerulosclerosis, Focal Segmental/complications , Glomerulosclerosis, Focal Segmental/diagnosis , Humans , Immunosuppressive Agents/therapeutic use , Infant , Logistic Models , Male , Multivariate Analysis , Predictive Value of Tests , Prognosis , Proteinuria/etiology , Renal Insufficiency/etiology , Retrospective Studies , Treatment Outcome
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