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Accurately staging hepatitis C virus (HCV)-related fibrosis is crucial for treatment decisions and prognostication. Our objective was to systematically review studies describing the accuracy of serum marker panels for predicting fibrosis in HIV/HCV-coinfected patients.Studies comparing serum marker panels with biopsy in HIV/HCV-coinfected patients were identified. Random effects meta-analyses and areas under summary receiver operating characteristics curves (AUC) examined test accuracy for detecting significant fibrosis (F2-4) and cirrhosis. Heterogeneity was explored using meta-regression.Five studies (n = 574) including four fibrosis measures (APRI [n = 4 studies], Forns' [n = 2], FibroTest [n = 1], SHASTA [n = 1]) met the inclusion criteria. The prevalence of significant fibrosis and cirrhosis were 51% and 16%, respectively. For the prediction of significant fibrosis, the summary AUC was 0.82 (95% CI 0.78-86) and diagnostic odds ratio was 7.8 (5.1-11.9). For cirrhosis, these figures were 0.83 (0.69-0.97) and 11.0 (4.6-26.2), respectively. Meta-regression including study factors (methodological quality and biopsy adequacy), patient characteristics (age, gender, CD4 count), and fibrosis measure failed to identify important predictors of accuracy.Available fibrosis marker panels have acceptable performance for identifying significant fibrosis and cirrhosis in HIV/HCV-coinfected patients but are not yet adequate to replace liver biopsy. Additional studies are necessary to identify the optimal measure.

This work is a part of long program for producing natural polymers which is used for application in different purposes in agriculture fields. A part of this program was the preparation of various compositions of Gum Arabic (GA) and Poly vinyl alcohol (PVA) with studying its physical and chemical characters. Whereas, the present work was concerning with the evaluation of released amount of selected micronutrients from the same complex under laboratory and field conditions. In the laboratory, the prepared complex containing copper (Cu) or manganese (Mn) separately, were tested at different pH values for releasing at intervals. The obtained results showed the possibility of using the Mn+2 complex at 3000 mg kg−1. Moreover, the obtained results showed that the maximum released amount was obtained at pH 7.0. A field experiment was planed according to the resulted data obtained in laboratory. Samples were taken for elemental analysis either from soil or plants during all growth stages likeas vegetative, floweri...

A simple and sensitive spectrophotometric method is described for the determination of buclizine hydrochloride in bulk and tablets form. The method is based on the formation of charge-transfer complex between buclizine, as n-donor, and iodine, as Δ acceptor, which measured spectrophotometrically at 295 and 355 nm. A Job's plot indicated a 1:1 complex between the drug and iodine and Beer's law was obeyed in a concentration range of 4–30 μg ml−1. A more detailed investigation of the complex was made with respect to its association constant and the free energy change. The method is simple and sensitive and has been applied successfully to the analysis of laboratory-made tablets without any interference from the tablet excipients. To validate the method, the results obtained were compared statistically with a newly developed uv-derivative spectrophotometric method. The charge-transfer method was favored due to its higher sensitivity, cheap coast and available equipments.

Two easy to handle, sensitive and specific fluorimetric methods for the detection and determination of morphine in codeine are described. In method A the codeine sample investigated is treated with alkaline potassium ferricyanide, whereby morphine when present will produce the fluorescent dimer pseudomorphine. In method B, the codeine sample is thermally treated with gaseous ammonia on a chromatographic plate where morphine, if present, is converted to a highly fluorescent derivative. The limits of detection were 10 ng and 20 ng for methods A and B respectively.

Second derivative spectrophotometry has been used to determine canrenone (I), the main degredation product in spironolactone (II). Second derivative at 300 nm was found linearly related to concentration in the range of 0.2–1 mg% I has been determined in II down to concentration level of 0.2 mg%. The results were found reproducible with a relative standard deviation of 1.7%.

The dye-salt formation method was successfully applied to the determination of chlorpheniramine maleate and chlorphenoxamine hydrochloride each in presence of caffeine. At pH 5, the chromogens (λmax=420 nm) produced with methyl orange in chloroform obeyed Beer's law over the range 5-15 ug/ml and with relative SD less than 1%.

An isocratic, sensitive high-per-Formance liquid chromatographic method has been developed for the determination of phenobarbitone, methylphenobarbitone and phenytoin in tablets. A reversed-phase octadecylsilane column, 10 µ, was utilized with a mobile phase consisting of 45% methanol, 55% water and 0.5 ml glacial acetic acid at a flow rate of 1.8 ml/min. The samples were dissolved in methanol containing diethylbarbituric acid as an internal standard. Quantitation was achieved with UV detection at 240 nm and by the measurment of the peak area ratio.

Potassium guaiacolsulphonate has been determined in a cough syrup by recording the second (D2) derivative absorption curve and taking D2 at 288 nn as a direct measure of its concentration. the mean percentage found from the labelled +SD was found to be 103.3+0.35. Added recovery experiments gave a mean percentage recovery of 100.3+0.24. the results were found to be in good agreement with those obtained using a spectro-fluorimetric method. the D2 method has been found to be reproducible with a relative standard deviation less than 1%.

Four two-component mixtures have been assayed using both Vierordt's and first derivative spectrophotometric methods. Such mixtures are acepifylline and phenobarbitone, phenylbutazone and amidopyrine, procaine and caffeine, and sulphamethoxazole and trimethoprim. These selected applications illustrate the relative ease and simplicity offered by first derivative spectrophotometry for the assay of two component mixtures with spectral interferences from matrix formulations.

The increment method under least squares has been applied to the spectrophotometric determination of p-hydroxybenzoic acid complexed with polyvinylpyrrolidone in water. The mean percentage recovery for six prepared mixtures was found to be 99.49 + 1.25. When the Amax method has been applied, the mean percentage recovery was found to be 90.99+5.59. The theoretical bases of the method have been discussed.

The use of first derivative spectrophotometry for the simultaneous determination of certain drugs in multicomponent formulations is presented. The method is illustrated by the determination of antazoline hydrochloride, phenylephrine hydrochloride and ephedrine hydrochloride in eye drops and acepifylline, phenobarbitone and papaverine hydrochloride in suppositories. These selected applications illustrate the relative ease and simplicity offered by first derivative spectrophotometry for the assay of three-component mixtures with spectral interferences from matrix formulations.

Cycloserine has been determined by a spectrophotometric method based on n → charge-transfer complex formation with chloranil. The method involves addition of cycloserine solution to chloranil reagent in borate buffer of pH 9; and heating at 65°C for 45 min. The complex formed exhibits absorption maximum of 348 nm; and Amax is linearly related to concentration over the range 2–8 μg/ml. The mean percentage found for the authentic sample is 100.32 ± 0.70. When applied to commercial capsules claimed to contain 250 mg each, the mean percentage found is 102.45 ± 1.05. These results have shown good agreement when compared with those obtained by the pharmacopoeial (B.P.) methods.

The first derivative curve (D1) of absorption spectrum of Phenytoin in buffer pH 10 develos negative peaks at 244, 263 and 270 nm. D1 at 244 nm was found linearly related to concentration over a range 0.4 − 1.4 mg per 100 ml and highly reproducible (C.V. %=0.62). Tablets and capsules have been analyzed using D1 at 244 nm and the mean percentage found were 99.7 ± 0.81 and 103.3 ± 0.44, respectively. The B.P. method gave 100.9 and 103.8 %, respectively.

Two proposed methods have been described for the determination of prenalterol hydrochloride in acetate buffer (pH=4.1) as authentic material and in tablets form using a (i) colorimetric method based on reduction of ferric iron by prenalterol hydrochloride and subsequent measurement at 511 nm of the red color obtained by the treatment of the resultant ferrous iron with 1, 10-orthophenanthroline, (ii) a differential pulse polarographic method based on nitrosation with 0.1 M NaNO2/dil. HC1 and consequent recording of the differential pulse polarogram. The differential polarogram was obtained under constant amplitude pulses of 50 mV (DP 50) superimposed on a linearly increasing DC-voltage ramp. The peak height (h), of the polarogram was measured at the peak potential of -0.2V on the dropping mercury electrode (DME) versus Ag/AgCl reference electrode. The linearity ranges observed are 0.6μgfml to 6.0μg/ml and 2μg/ml to 12μg/ml, respectively. The mean percentage recoveries for an authentic sample are 9...