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1.
Cureus ; 16(2): e53996, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38476797

ABSTRACT

Introduction For spastic hip dislocations, a variety of operations are available with open hip reduction and varus derotational osteotomy of the proximal femur combined with pelvic osteotomy ± adductor release being a good option with favourable outcomes. This study aims to assess the outcome and complications of combined open hip reduction with pelvic osteotomy and varus derotational osteotomy. Methods In this study, 70 hips in 52 patients with spastic hip dislocation due to cerebral palsy were included. All included patients were treated surgically in our institute between January 2016 and December 2021. There were 31 males and 21 females. For each patient, information was collected about the age at the time of surgery and different radiological parameters at three different time intervals: pre-operatively, immediately post-operatively, and at the final follow-up. We also collected information about any complications arising from the surgery performed. Results The mean duration of follow-up was 19.58 months. The acetabular index decreased from an average of 35.01° to 17.18° with a mean difference of 17.83° (p<0.001). The central edge angle, which averaged -49.13° in the pre-operative period, increased to 26.34° and then marginally decreased to 25.47° at the final follow-up. The average migration index of 80.51% in the pre-operative period improved to 1.4% post-operatively with a mean difference of -79.11% (p<0.01). The migration index increased to 8.54% at the final follow-up. Similarly, the neck-shaft angle, which averaged 160.89° in the pre-operative period, decreased to 125.23° at the time of final follow-up with a percentage change of -22.16%. Conclusion Single-stage combined surgery in the form of combined open hip reduction and pelvic osteotomy with varus derotational osteotomy successfully treats the condition and shows good outcomes in patients with spastic hip dislocations. This treatment is associated with very few complications.

2.
Saudi Med J ; 44(7): 674-678, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37463703

ABSTRACT

OBJECTIVES: To explore the effects of empagliflozin (25 mg) on metabolic and renal parameters in patients with type 2 diabetes mellitus (T2DM). METHODS: This retrospective observational comparative study was conducted at a military hospital in southern Saudi Arabia. All adults (aged >18 years) with T2DM who attended diabetic clinics between October 2021 to March 2022 (6 months), with or without insulin treatment, were eligible for inclusion in the study. RESULTS: Following the initiation of empagliflozin treatment, statistically significant reductions in patient weight (kg) were observed at 1, 3-5, and 6 months. In addition, low-density lipoprotein levels significantly decreased 3-5 months post-treatment initiation (p=0.011). However, serum creatinine level decreased gradually with time during the treatment with empagliflozin, from 87.45±31.78 (0.105) to 78.39±27.43 (0.033). Furthermore, after empagliflozin treatment, the urinary albumin-to-creatinine ratio significantly decreased at 3-5 and 6 months. Moreover, HbA1c levels exhibited statistically significant decreases at 3-5 months (p<0.001) and at 6 months (p<0.001) following the initiation of empagliflozin treatment. Notably, systolic and diastolic blood pressure significantly reduced 6 months after empagliflozin treatment. CONCLUSION: In the current study, empagliflozin has demonstrated efficacy in controlling blood pressure and body weight, and improving renal function, short-term dyslipidemia, and glycemic control in patients with T2DM.


Subject(s)
Diabetes Mellitus, Type 2 , Adult , Humans , Retrospective Studies , Saudi Arabia , Glycated Hemoglobin , Benzhydryl Compounds/therapeutic use , Kidney/physiology , Hospitals , Hypoglycemic Agents/therapeutic use
3.
Cureus ; 14(10): e30058, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36381902

ABSTRACT

INTRODUCTION: Posterior spinal instrumented fusion remains the mainstay treatment for adolescent idiopathic scoliosis (AIS) with acceptable post-operative patient satisfaction. However, in Saudi Arabia, patient satisfaction after surgical management for AIS has not been thoroughly studied. The purpose of this study was to determine patient satisfaction and quality of life using the Scoliosis Research Society-22r (SRS-22r, the most recent version) questionnaire after surgical correction of AIS in Saudi Arabia. METHODS: A retrospective study was conducted that included patients who underwent posterior spinal instrumented fusion for AIS from January 1995 through December 2015. We included 115 patients (both males and females) in our study. We used the Arabic version of the SRS-22r questionnaire that was completed through telephonic interviews. Data collected were then analyzed using SPSS Statistics, version 23. RESULTS: The mean age of our patients at the time of surgery was 15.0 ± 2.6 years and the average time from surgery to interview was 9.4 ± 4.7 years. A positive response was recorded in all domains including pain, function, mental health, and self-image. Furthermore, 76.5% of the patients were satisfied with their management outcome and 81.7% of the patients reported no complications. CONCLUSION: Surgical correction of AIS improved the quality of life of our patients that was assessed using the Arabic version of the SRS-22r questionnaire. Apart from overall patient satisfaction, positive responses were recorded in all four domains of the SRS-22r questionnaire.

4.
Cureus ; 13(6): e15669, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34277260

ABSTRACT

Müllerian duct aplasia-renal agenesis-cervicothoracic somite dysplasia (MURCS) association is a rare syndrome. This unique condition consists of Müllerian duct aplasia, cervicothoracic somite dysplasia, and renal aplasia, and skeletal abnormalities manifesting in childhood. We report the case of a 14-year-old girl who presented to the orthopedic clinic with spinal deformity and Sprengel's shoulder complicated by a background of MURCS association. The treatment modalities of scoliosis include posterior spinal fusion and the vertical expandable prosthetic titanium rib. On the other hand, Sprengel's deformity is surgically managed by Woodward's procedure. The management plan for our patient involved correcting scoliosis by the posterior spinal fusion procedure and performing Woodward's procedure to correct Sprengel's deformity simultaneously. Simultaneous scoliosis correction with posterior spinal instrumented fusion and Sprengel's deformity correction with modified Woodward's procedure is a promising surgical technique that can lead to favorable outcomes.

5.
Cureus ; 13(3): e14167, 2021 Mar 29.
Article in English | MEDLINE | ID: mdl-33936879

ABSTRACT

INTRODUCTION: In congenital anomalies of the thoracic spine, fusion in situ and hemi-epiphysiodesis are unsuitable surgical options, because three-dimensional thoracic deformity and insufficiency are uncorrectable. We aimed to evaluate the radiological outcome of vertical expandable titanium rib (VEPTR) application after follow-up in children with congenital scoliosis with or without rib fusion. METHODS: In our study, we included 58 patients with congenital scoliosis with or without fused ribs; all treated with VEPTR from 2005 to 2015 at our institute. There were 19 males and 39 females. For each patient, we collected information about age at the index surgery (VEPTR application) and the total number of VEPTR lengthening procedures. Also, Cobb angle, kyphotic angle, thoracic height, and spinal height were measured on preoperative radiographs, immediately post-operative, two years post-operative, and at final follow-up. RESULTS: The mean duration of follow-up was five years (range, 2-12 years). Twenty-eight patients had rib-to-pelvis type VEPTR, 20 patients had rib-to-rib type VEPTR, and 10 patients had a rib to pedicle/lamina type of VEPTR implant. Post-VEPTR, 63.8% of our patients reported one or more complications. The immediate post-VEPTR application showed that the mean Cobb angle decreased to 43.56° with a percentage change of 22.8% (p<0.001). The mean increase in thoracic height between VEPTR application surgery and final follow-up was 32 mm with a 19.3% increase (p<0.001). Similarly, the mean increase in the spinal height between the VEPTR application surgery and final follow-up was 46.6 mm, with a 23% increase (p<0.001). CONCLUSIONS: VEPTR instrumentation for congenital scoliosis, with or without rib fusion, successfully corrects the coronal Cobb angle in the majority of patients. It also allows the thoracic (T1-T12) and spinal (T1-S1) growth to approach normal for a particular age.

6.
SICOT J ; 6: 41, 2020.
Article in English | MEDLINE | ID: mdl-33030426

ABSTRACT

INTRODUCTION: This study aimed to evaluate the use of a cell savage and its impact on the amount of allogenic blood transfused to the patients during idiopathic scoliosis surgery. METHODS: A total of 142 randomly selected patients with scoliosis had been included in this study. The adult group consisted of 78 patients, and the pediatric group, 64 patients. Both groups were divided into subgroups (pre-cell saver era and cell saver era). Data on the following parameters were collected: amount of blood transfused intraoperatively, within 24 h postoperatively, and overall. The number of patients who received transfusion was counted as the number of patients who avoided any transfusion. For statistical purposes, we performed unpaired student t-test, chi-square test, and Mann-Whitney test. RESULTS: There was no significant difference in adult groups perioperatively. In the pediatric group, there was a statistically significant difference intraoperatively. Economic analysis of blood management showed positive numbers for both groups, where more than 1 unit of blood was transfused. CONCLUSIONS: Statistical analysis showed the cost-effectiveness of the perioperative use of cell salvage during pediatric scoliosis surgery. Overall, the use of cell salvage during scoliosis surgery had a positive impact on both blood management and patient recovery.

7.
BMC Musculoskelet Disord ; 21(1): 283, 2020 May 07.
Article in English | MEDLINE | ID: mdl-32381079

ABSTRACT

BACKGROUND: Synovial sarcoma (SS) is one of the reported sarcomas in the pediatric and adult populations. Delay in diagnosis and treatment is common in SS cases. SS may be excised before the correct diagnosis is made. CASE PRESENTATION: we present a case involving a 4-year-old boy who visited our service with complaints of left knee pain and limited knee flexion. Initially, the child was diagnosed with osteochondromatosis. Surgical excision was opted, and initial histopathological examination revealed a fibrous histiocytoma. The slide and blocks were then brought to the King Faisal Specialist Hospital Research Center (KFSH&RC) and histopathologic analysis has shown a well-circumscribed nodule in the synovium with a sub-synovial monomorphic spindle cell sarcoma, confirmed by fluorescence in situ hybridization (FISH). CONCLUSIONS: Therefore, we strongly recommend considering all differential diagnoses for soft-tissue masses when planning surgical management.


Subject(s)
Diagnostic Errors , Histiocytoma, Benign Fibrous/diagnosis , Osteochondromatosis/diagnosis , Sarcoma, Synovial/diagnosis , Soft Tissue Neoplasms/diagnosis , Child, Preschool , Diagnosis, Differential , Follow-Up Studies , Humans , In Situ Hybridization, Fluorescence , Knee Joint/pathology , Knee Joint/surgery , Male , Range of Motion, Articular , Sarcoma, Synovial/surgery , Soft Tissue Neoplasms/surgery , Treatment Outcome
8.
Ann Pharm Fr ; 77(1): 28-37, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30172351

ABSTRACT

Alfuzosin and tamsulosin are recently co-administrated with vardenafil to treat symptoms of benign prostatic hyperplasia and erectile dysfunction. A highly sensitive and simple liquid chromatographic method was developed and validated for the simultaneous determination of the three drugs using moxifloxacin as an internal standard. Isocratic separation was achieved within 7.0 min using phenyl-hexyl column (250 × 4.6 mm i.d.) and a mobile phase composed of acetonitrile/0.25% phosphoric acid (30:70, v/v) at pH 3.0. The analysis was performed at a flow rate of 1.2 mL/min with fluorescence detection at 246/450 nm for Alfuzosin and vardenafil, and 226/322nm for tamsulosin using time programming technique. The proposed method was linear over the concentration ranges of 5.0-50.0ng/mL, 10.0-200.0ng/mL and 20.0-400.0ng/mL for alfuzosin, vardenafil and tamsulosin, with limits of detection of 0.56ng/mL, 0.98ng/mL and 2.81 ng/mL in a respective order. The developed method was successfully applied to determine the studied drugs in dosage forms and human plasma samples and the results were satisfactory as revealed by statistical analysis of the data.


Subject(s)
Adrenergic alpha-Antagonists/blood , Antihypertensive Agents/blood , Quinazolines/blood , Tamsulosin/blood , Vardenafil Dihydrochloride/blood , Vasodilator Agents/blood , Chromatography, High Pressure Liquid , Drug Compounding , Humans , Male , Prostatic Hyperplasia/drug therapy , Reference Standards , Reproducibility of Results , Spectrometry, Fluorescence
9.
Biotech Histochem ; 91(8): 532-539, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27849398

ABSTRACT

Endothelial progenitor cells (EPC) participate in revascularization and angiogenesis. EPC can be cultured in vitro from mononuclear cells of peripheral blood, umbilical cord blood or bone marrow; they also can be transdifferentiated from mesenchymal stem cells (MSC). We isolated EPCs from Wharton's jelly (WJ) using two methods. The first method was by obtaining MSC from WJ and characterizing them by flow cytometry and their adipogenic and osteogenic differentiation, then applying endothelial growth differentiating media. The second method was by direct culture of cells derived from WJ into endothelial differentiating media. EPCs were characterized by morphology, Dil-LDL uptake/UEA-1 immunostaining and testing the expression of endothelial markers by flow cytometry and RT-PCR. We found that MSC derived from WJ differentiated into endothelial-like cells using simple culture conditions with endothelium induction agents in the medium.


Subject(s)
Cell Differentiation/physiology , Endothelial Progenitor Cells/cytology , Mesenchymal Stem Cells/cytology , Osteogenesis/physiology , Wharton Jelly/cytology , Cell Culture Techniques , Cell Proliferation/physiology , Cells, Cultured , Flow Cytometry , Humans
10.
Springerplus ; 4: 89, 2015.
Article in English | MEDLINE | ID: mdl-25763301

ABSTRACT

Monitoring of pest populations is an essential component of integrated pest management. An early warning system helps growers decide when best to take control measures, or when to alter them, should a control method prove inadequate. Studies have shown that adding chemical attractants to sticky cards can increase trap catch of western flower thrips, Frankliniella occidentalis, a global pest of agriculture and horticulture, giving more accurate accounts of population size and dynamics, thus leading to more efficient monitoring. We identify a novel semiochemical to the species, (S)-(-)-verbenone, showing that addition of this compound to sticky traps significantly increased F. occidentalis catch in two geographically distinct populations, infesting two unrelated crops of global economic importance. We validate through field trials that (S)-(-)-verbenone is highly attractive to F.occidentalis and can be used with blue sticky traps to enhance trap catch, leading to better estimations of pest population densities. The compound may be used in other control methods against F.occidentalis such as lure and kill, mass trapping and push-pull.

11.
Chemoecology ; 25: 47-51, 2015.
Article in English | MEDLINE | ID: mdl-25598579

ABSTRACT

Stereochemistry plays a significant role in structure-activity relationships of messenger chemicals. The ability to distinguish between enantiomers and geometric isomers, however, may be limited to certain stereoisomeric substances, depending on the receiver. In this study, we assessed the preference of the peripheral olfactometry system of Western Flower Thrips, F. occidentalis towards ubiquitously expressed host compounds, with a goal of establishing whether particular stereoisomers enhance host odour recognition. We demonstrate that the peripheral olfactory system of a highly polyphagous thysanopteran insect has evolved to become highly sensitive to a type of green leaf volatile, which is highly ubiquitous in the plant kingdom. We show that there is a significantly greater antennal response to the cis isomer, more so than the isomerisation by-product trans-3-hexen-1-ol. We demonstrate that the antennae of a highly polyphagous insect are capable of detecting common plant secondary metabolites in both enantiomeric forms.

12.
J Chem Ecol ; 40(6): 534-40, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24879603

ABSTRACT

Pollinophagy is widely documented in the order Thysanoptera, with representative individuals from six of the nine divergent families known to feed on pollen. Various pollens of the genus Pinus increase the development time, fecundity, longevity, and settling preference of Western Flower Thrips (WFT), Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). Certain species of flower thrips discriminate among pollen types, but no studies have elucidated the olfactory cues that play a role in their pollen preferences. In this study, the volatile organic compounds emitted by pollens of the genus Pinus were elucidated. Various chemicals from pollen headspace elicited electrophysiological responses from WFT antennae. The compound (S)-(-)-verbenone, identified in pollen headspace, attracted WFT in a 4-arm olfactometer. This compound has potential for use in integrated pest management programs against the pest. We present the hypothesis that this polyphagous insect may have retained ancestral 'relict' olfactory receptors through the course of evolution, to explain this attraction to pine pollen. This attraction has allowed the insect to find and exploit an unusual nutrient source that significantly increases its fitness. The study demonstrates how fossil record analysis and subsequent evolutionary knowledge can aid in explaining possibilities as to why some insects sense and respond to chemicals that would otherwise seem peculiar to their ecology, allowing insight into the evolutionary forces that may shape insect olfactory systems over time.


Subject(s)
Olfactory Receptor Neurons/physiology , Pinus , Pollen/chemistry , Thysanoptera/physiology , Animals , Arthropod Antennae/physiology , Behavior, Animal , Bicyclic Monoterpenes , Electrophysiological Phenomena , Female , Pollen/physiology , Terpenes , Volatile Organic Compounds/analysis
13.
Article in English | MEDLINE | ID: mdl-23872160

ABSTRACT

A simple and sensitive HPLC method has been developed for the determination of aliskiren in human plasma through derivatization with 1-naphthyl isocyanate. The separation was achieved on a C18 column using a mobile phase consisting of acetonitrile/water/phosphoric acid (45:55:0.01, v/v/v, pH 3.2) in a flow rate of 1mL/min with UV detection at 230nm. Caffeine was used as an internal standard. The factors influencing the derivatization reaction yields were carefully studied and optimized. The method was linear over the concentration range of 5-400ng/mL with a detection limit of 0.5ng/mL and a limit of quantification of 1.0ng/mL. The relative standard deviation was less than 4.2% for both intra-day assay and inter-day assay results. No interferences from endogenous compounds were encountered. The percentage recovery was in the range 97.1-98.6%. The method is suitable for routine therapeutic drug monitoring and for pharmacokinetic studies.


Subject(s)
Amides/blood , Antihypertensive Agents/blood , Chromatography, High Pressure Liquid/methods , Fumarates/blood , Spectrophotometry, Ultraviolet/methods , Drug Monitoring , Humans , Isocyanates/chemistry , Limit of Detection , Naphthalenes/chemistry
14.
Pharmazie ; 68(12): 933-8, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24400438

ABSTRACT

An alternative method for analysis of aliskiren (ALI) and hydrochlorothiazde (HCT) in combined dosage forms by ion-pair reversed phase high performance liquid chromatography was developed and validated. The pharmaceutical preparations were analyzed using a C18 column (250 mm x 4.6 mm, 3 microm) with a mobile phase consisting of 25% methanol, 50% sodium monobasic phosphate aqueous solution containing 6 mM tetrabutylammonium bromide and 25% water at pH 7.2. Isocratic analysis was performed at a flow rate of 1 mL/min and a column temperature of 30 degrees C under direct UV detection at 210 nm. Paracetamol was used as internal standard. The validation was performed according to the ICH guidelines. The proposed method was linear over the concentration range of 0.250 to 60 and 0.1 to 10 microg/mL for ALI and HCT, respectively. The limits of detection and quantitation (LOD and LOQ) were 0.075 and 0.198 microg/mL, respectively, for ALI and 0.04 and 0.062 microg/mL, respectively, for HCT. The method proved to be specific, sensitive, precise and accurate with mean recovery values of 101.1 +/- 0.32% and 100.9 +/- 0.41% for ALI and HCT, respectively. The method robustness was evaluated by means of an experimental design. The proposed method was applied successfully to spiked human urine samples with mean recoveries of 98.8 +/- 0.36% and 98.1 +/- 0.21% for ALI and HCT, respectively.


Subject(s)
Amides/analysis , Amides/urine , Antihypertensive Agents/analysis , Antihypertensive Agents/urine , Diuretics/analysis , Diuretics/urine , Fumarates/analysis , Fumarates/urine , Hydrochlorothiazide/analysis , Hydrochlorothiazide/urine , Calibration , Chromatography, High Pressure Liquid , Humans , Hydrogen-Ion Concentration , Indicators and Reagents , Limit of Detection , Quality Control , Reference Standards , Reproducibility of Results , Spectrophotometry, Ultraviolet , Tablets/analysis
15.
J Med Genet ; 49(10): 630-5, 2012 Oct.
Article in English | MEDLINE | ID: mdl-23054245

ABSTRACT

BACKGROUND: Osteogenesis imperfecta (OI) is an hereditary bone disease in which increased bone fragility leads to frequent fractures and other complications, usually in an autosomal dominant fashion. An expanding list of genes that encode proteins related to collagen metabolism are now recognised as important causes of autosomal recessive (AR) OI. Our aim was to study the contribution of known genes to AR OI in order to identify novel loci in mutation-negative cases. METHODS: We enrolled multiplex consanguineous families and simplex cases (also consanguineous) in which mutations in COL1A1 and COL1A2 had been excluded. We used autozygome guided mutation analysis of AR OI (AR OI) genes followed by exome sequencing when such analysis failed to identify the causative mutation. RESULTS: Two simplex and 11 multiplex families were enrolled, encompassing 27 cases. In three multiplex families, autozygosity and linkage analysis revealed a novel recessive OI locus on chromosome 9q31.1-31.3, and a novel truncating deletion of exon 4 of TMEM38B was identified within that interval. In addition, gonadal or gonadal/somatic mosaic mutations in COL1A1 or COL1A2 and homozygous mutations in recently described AR OI genes were identified in all remaining families. CONCLUSIONS: TMEM38B is a novel candidate gene for AR OI. Future studies are needed to explore fully the contribution of this gene to AR OI in other populations.


Subject(s)
Genes, Recessive , Ion Channels/genetics , Mutation , Osteogenesis Imperfecta/genetics , Arabia , Base Sequence , Collagen Type I/genetics , Collagen Type I, alpha 1 Chain , Consanguinity , Exons , Female , Gene Order , Homozygote , Humans , Infant , Infant, Newborn , Male , Osteogenesis Imperfecta/diagnosis
16.
Anal Sci ; 27(5): 535, 2011.
Article in English | MEDLINE | ID: mdl-21558662

ABSTRACT

The anodic voltammetric behavior of tiapride hydrochloride (TiapCl) was studied at carbon paste electrodes in 0.04 M Britton-Robinson buffer pH 7.0 using cyclic and differential pulse voltammetric techniques. The oxidation of TiapCl is an irreversible diffusion-controlled process. A differential pulse anodic voltammetric procedure has been developed for determination of the drug over the concentration range 0.36 - 19.35 µg/ml with detection and quantification limits of 0.12 and 0.40 µg/ml, respectively. The proposed method was successfully applied for the determination of the drug in commercial tablets and in spiked human urine samples.


Subject(s)
Carbon/chemistry , Pharmaceutical Preparations/chemistry , Tiapamil Hydrochloride/analysis , Electrochemistry , Electrodes , Humans , Oxidation-Reduction , Reference Values , Sensitivity and Specificity
18.
Anal Sci ; 26(1): 45-9, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20065586

ABSTRACT

The construction and electrochemical response characteristics of two new polyvinyl chloride (PVC) membrane sensors for the determination of sibutramine hydrochloride were described. The sensors are based on the ion association complexes of sibutramine with sodium tetraphenylborate (NaTPB) or phosphotungstic acid (PTA) using dibutyl phthalate as plasticizing solvent. The sensors display a fast, stable response over the concentration range 3.84 x 10(-5)-1.00 x 10(-2) M sibutramine hydrochloride monohydrate (SibuCl), with cationic slopes of 57.7 +/- 0.57 and 59.7 +/- 1.79 mV concentration decade(-1) and detection limits of 8.91 x 10(-6) and 1.47 x 10(-5) M in case of sibutramine-tetraphenylborate (Sibu-TPB) and sibutramine-phosphotungstate ((Sibu)(3)-PT), respectively. The proposed sensors have been successfully applied for the determination of sibutramine hydrochloride in Regitrim capsules in batch and flow injection (FI) conditions.


Subject(s)
Appetite Depressants/analysis , Cyclobutanes/analysis , Pharmaceutical Preparations/analysis , Calibration , Capsules/analysis , Dibutyl Phthalate/chemistry , Electrodes , Electrolytes/chemistry , Flow Injection Analysis , Hydrogen-Ion Concentration , Indicators and Reagents , Membranes, Artificial , Phosphotungstic Acid/chemistry , Polyvinyl Chloride/chemistry , Potentiometry , Temperature , Tetraphenylborate/chemistry
19.
Bioelectrochemistry ; 75(1): 9-12, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19138886

ABSTRACT

The stripping voltammetric behaviour of drotaverine hydrochloride (DvCl) was studied using a hanging mercury drop electrode (HMDE). The adsorptive stripping response has been evaluated with respect to pH, accumulation time, accumulation potential, scan rate and other variables. Differential pulse DP mode; over the potential range -400 to -1200 mV, is used in the presence of 0.04 M Britton-Robinson buffer pH 2. Cyclic voltammetric study indicates that the reduction process is irreversible and controlled by adsorption. The response of DP technique is linear over the concentration range 21.70-257.34 ng/ml. Limit of detection and limit of quantification were 3.15 and 10.50 ng/ml, respectively. The proposed method was successfully applied for the determination of the drug in commercial tablets and spiked human urine samples.


Subject(s)
Chemistry Techniques, Analytical/methods , Papaverine/analogs & derivatives , Tablets/chemistry , Adsorption , Calibration , Humans , Hydrogen-Ion Concentration , Molecular Structure , Papaverine/analysis , Papaverine/urine
20.
J Environ Sci Health B ; 43(7): 595-604, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18803114

ABSTRACT

The dissipation of (O-methyl-14C) monocrotophos and U-ring labelled 14C-carbaryl was monitored for over two years in absence and presence of other insecticides using in situ soil columns. The dissipation of 14C-monocrotophos from soil treated with methomyl and carbaryl showed a faster rate of downward movement than in a control column tagged with the labelled insecticide alone. The same trend was observed in experiments with 14C-carbaryl that dissipated more readily in soil treated with non-labelled monocrotophos and methomyl. In the presence of other insecticides the percentage of bound residues was generally lower than in control experiments. The bound residues at the top of the column are released at a low rate under conditions prevailing in the field. The overall time required for dissipation of 50% of monocrotophos and carbaryl (t50) as estimated from control experiment was approximately 20 and 24 weeks, respectively. The data indicate that repeated applications of pesticides might enhance the release of 14C-bound residues.


Subject(s)
Carbaryl/chemistry , Carbaryl/metabolism , Monocrotophos/chemistry , Monocrotophos/metabolism , Soil Pollutants/chemistry , Soil Pollutants/metabolism , Soil/analysis , Carbon Isotopes/analysis , Monocrotophos/analysis , Pesticides , Time Factors
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