Detection of A2142C, A2142G, and A2143G Mutations in 23s rRNA Gene Conferring Resistance to Clarithromycin among Helicobacter pylori Isolates in Kerman, Iran

Psychedelic/entactogen‐assisted therapy for treatment of anxiety, depression and existential distress in adult palliative care

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To assess the benefits and harms of psychedelic/entactogen‐assisted therapy compared to placebo or active comparators (e.g. antidepressants) for treatment of anxiety, depression, and existential distress in adult palliative care.

Evaluation of the Efficiency of Smart Stability-Indicating Spectrophotometric Methods Based on Mathematical and Statistical Processing of the Obtained Results Via Different Manipulating Pathways

Background:

Smart different stability-indicating spectrophotometric methods have been established for the assay of chlordiazepoxide and clidinium bromide without the intervention of alkaline degradate of clidinium via various and different manipulating pathways without previous separation steps.

Objective:

The specificity of the established methods was inspected by analysing mixtures of cited drugs in the existence of the alkali-induced degradation product.

Methods:

These methods were employed either on scanned zero-order absorption spectra using absorbance subtraction, dual wavelength and Q-absorbance ratio or the amplitudes of the ratio spectra of zero-order absorption spectra like amplitude modulation and by derivative techniques to the ratio spectra as a derivative ratio method. In addition, the absorbance of the recovered zero-order absorption spectra was applied by successive ratio subtraction coupled with constant multiplication. Finally, the pathway depends on the amplitudes of the derivative spectra, successive derivative subtraction coupled with constant multiplication. The ranges of linearity were (1-12µg/mL) for chlordiazepoxide and (3- 12µg/mL) for clidinium bromide.

Results:

The outcomes achieved by the prospective methods were in consent with those of the official and reported methods when statistically compared using student’s t test, F-test and one-way ANOVA where no significant difference was detected with suitable precision, proving the absence of any important difference in accuracy and precision between them. They were confirmed in accordance with International Conference on Harmonization guidelines.

Conclusion:

The established methods can be considered as alternative methods for the routine determination of this fixed dose combination with minimum sample preparation.

Reduction of interferences in the analysis of Children's Dimetapp using ultraviolet spectroscopy data and target factor analysis

A calibration matrix has been developed and successfully applied to quantify actives in Children's Dimetapp®, a cough mixture whose active components suffer from heavy spectral interference. High-performance liquid chromatography/photodiode array instrument was used to identify the actives and any other UV-detectable excipients that might contribute to interferences. The instrument was also used to obtain reference data on the actives, instead of relying on the manufacturer's claims. Principal component analysis was used during the developmental stages of the calibration matrix to highlight any mismatch between the calibration and sample spectra, making certain that "apples" were not compared with "oranges". The prediction model was finally calculated using target factor analysis and partial least squares regression. In addition to the actives in Children's Dimetapp® (brompheniramine maleate, phenylephrine hydrogen chloride, and dextromethorphan hydrogen bromide), sodium benzoate was identified as the major and FD&C Blue #1, FD&C Red #40, and methyl anthranilate as minor spectral interferences. Model predictions were compared before and after the interferences were included into the calibration matrix. Before including interferences, the following results were obtained: brompheniramine maleate=481.3mgL^-1±134% RE; phenylephrine hydrogen chloride=1041mgL^-1±107% RE; dextromethorphan hydrogen bromide=1571mgL^-1±107% RE, where % RE=percent relative error based on the reference HPLC data. After including interferences, the results were as follows: brompheniramine maleate=196.3mgL^-1±4.4% RE; phenylephrine hydrogen chloride=501.3mgL^-1±0.10% RE; dextromethorphan hydrogen bromide=998.7mgL^-1±1.6% RE as detailed in Table 6.

Simultaneous HPLC Determination of Chlordiazepoxide and Mebeverine HCl in the Presence of Their Degradation Products and Impurities

A simple, rapid, and sensitive RP-HPLC method was developed and validated for the simultaneous determination of chlordiazepoxide (CDO) and mebeverine HCl (MBV) in the presence of CDO impurity (2-amino-5-chlorobenzophenone, ACB) and MBV degradation product (veratric acid, VER). Separation was achieved within 9 min on a BDS Hypersil phenyl column (4.5 mm × 250 mm, 5 µm particle size) using a mobile phase consisting of acetonitrile: 0.1 M potassium dihydrogen phosphate: triethylamine (35 : 65 : 0.2, v/v/v) in an isocratic mode at a flow rate of 1 mL/min. The pH of the mobile phase was adjusted to 4.5 with orthophosphoric acid and UV detection was set at 260 nm. A complete validation procedure was conducted. The proposed method exhibited excellent linearity over the concentration ranges of 1.0–100.0, 10.0–200.0, 2.0–40.0, and 2.0–40.0 µg/mL for CDO, MBV, VER, and ACB, respectively. The proposed method was applied for the simultaneous determination of CDO and MBV in their coformulated tablets with mean percentage recoveries of 99.75 ± 0.62 and 98.61 ± 0.38, respectively. The results of the proposed method were favorably compared with those of a comparison HPLC method using Studentt-test and the variance ratioF-test. The chemical structure of MBV degradation product was ascertained by mass spectrometry and IR studies.

Effects of emodin and other herbal extracts on resistance of Helicobacter pylori to clarithromycin

AIM: To evaluate the effects of emodin and other herbal extracts on resistance of Helicobacter pylori (H. pylori) to clarithromycin, and to explore the methods for effectively inhibiting H. pylori antibiotic resistance.

METHODS: The MIC of herbal extracts against clarithromycin resistance of H. pylori was detected by double dilution method. Clarithromycin resistant H. pylori was cultured in medium containing herbal extracts at a concentration of half MIC and passaged once every 5 d for 6 times. The MIC of clarithromycin against antibiotic resistance of H. pylori was assessed before and after stress culture. The DNA of H. pylori was extracted to detect drug resistant-related gene mutations.

RESULTS: The MIC of clarithromycin against H. pylori was reduced by herbal extracts. The gene mutations of 23s rRNA A2143G and A2144G were detected in clarithromycin-resistant H. pylori. No back mutations were discovered after treatment with herbal extracts for 30 d.

CONCLUSION: Herbal extracts have a synergistic effect in inhibiting the clarithromycin resistance of H. pylori. The synergistic action is not associated with the back mutations of 23s rRNA gene mutations related to clarithromycin resistance of H. pylori.

Simultaneous Determination of Clidinium Bromide and Chlordiazepoxide in Combined Dosage Forms by High-Performance Liquid Chromatography

A sensitive and precise RP-HPLC method has been developed for the simultaneous estimation of clidinium bromide (CDB) and chlordiazepoxide (CDZ) in pure and pharmaceutical formulations. The separation was achieved on a Nucleodur C₈ (250 × 4.6 mm i.d., 5 μm particle size) column at 25°C. CH₃CN-MeOH-NH₄OAc 0.1M (30 : 40 : 30, v/v/v) was used as the mobile phase at a flow rate of 1.0 mL min⁻¹ and detector wavelength at 218 nm. Almotriptan (ALT) was used as internal standard. The validation of the proposed method was carried out for linearity, accuracy, precision, LOD, LOQ, and robustness. The method showed good linearity in the ranges of 2.5–300.0 and 3.0–500.0 μg mL⁻¹ for CDB and CDZ, respectively. The percentage recovery obtained for CDB and CDZ was 100.40–103.38 and 99.98–105.59%, respectively. LOD and LOQ were 0.088 and 0.294 μg mL⁻¹ for CDB and 0.121 and 0.403 μg mL⁻¹ for CDZ, respectively. The proposed method was successfully applied to the determination of CDB and CDZ in combined dosage forms and the results tallied well with the label claim.