Anti-nociceptive effects of taurine and caffeine in sciatic nerve ligated wistar rats: involvement of autonomic receptors

In this study, we investigated the effects of co-administration of taurine and caffeine on thermally induced pain in sciatic nerve ligated rats as well as the roles of autonomic receptors. Rats were rendered neuropathic by unilateral sciatic nerve ligation. The anti-hyperalgesic effect of combined systemic (i.p.) administration of taurine and caffeine were assessed using tail flick tests and hot plate test for two weeks. To determine the involvement of autonomic nervous system, the study examined how administration of cholinergic (atropine and hexamethonium) and adrenergic (prazosin and propranolol) receptor blockers altered the combined effect of taurine and caffeine. Likewise, the serum level of oxidative stress marker malondialdehyde (MDA) was evaluated. The results showed that co-administration of taurine and caffeine attenuated thermal hyperalgesia in sciatic nerve ligated rats as shown by significant (p<0.05) increase in tail and paw withdrawal latencies in the treated groups compared to the ligated control group after two weeks of administration. The anti nociceptive effects were reversed by pre-treatment with cholinergic blockers especially atropine while the adrenergic blockers spared the effects of taurine and caffeine. Also, the increase in tissue level of MDA induced by sciatic nerve ligation was significantly attenuated by combined administration of high dose of taurine and caffeine. It can be concluded that co-administration of taurine and caffeine attenuates thermal hyperalgesia in sciatic nerve-ligated rats (a model of neuropathic pain) and this effect involves cholinergic system. The findings suggest that coadministration of taurine and caffeine might be useful for the treatment of neuropathic pain.Keywords: Caffeine, taurine hyperalgesia, neuropathic pain

Analysis of SARS-CoV-2 viral loads in stool samples and nasopharyngeal swabs from COVID-19 patients in the United Arab Emirates

Coronavirus disease 2019 (COVID-19) was first identified in respiratory samples and was found to commonly cause cough and pneumonia. However, non-respiratory symptoms including gastrointestinal disorders are also present and a big proportion of patients test positive for the virus in stools for a prolonged period. In this cross-sectional study, we investigated viral load trends in stools and nasopharyngeal swabs and their correlation with multiple demographic and clinical factors. The study included 211 laboratory-confirmed cases suffering from a mild form of the disease and completing their isolation period at a non-hospital center in the United Arab Emirates. Demographic and clinical information was collected by standardized questionnaire and from the medical records of the patient. Of the 211 participants, 25 % tested negative in both sample types at the time of this study and 53 % of the remaining patients had detectable viral RNA in their stools. A positive fecal viral test was associated with male gender, diarrhea as a symptom, and hospitalization during infection. A positive correlation was also observed between a delayed onset of symptoms and a positive stool test. Viral load in stools positively correlated with, being overweight, exercising, taking antibiotics in the last 3 months and blood type O. The viral load in nasopharyngeal swabs, on the other hand, was higher for blood type A, and rhesus positive (Rh factor). Regression analysis showed no correlation between the viral loads measured in stool and nasopharyngeal samples in any given patient. The results of this work highlight the factors associated with a higher viral count in each sample. It also shows the importance of stool sample analysis for the follow-up and diagnosis of recovering COVID-19 patients

COVID-19 specialized diabetes clinic model for excellence in diabetes care: scientific perspective

While diabetes centers are well established by the Ministry of Health, there is no separate specialized diabetes clinics for COVID-19 patients (SDCs). There are several clinical diabetes centers throughout the Kingdom of Saudi Arabia, several of which have been developed through philanthropy funding; nevertheless, it is not obvious what distinguishes SDCs from a therapeutic viewpoint and what the potential would be for such centers. Through this context, we suggest a structure to direct the progress of SDCs. Defining protocols for wider adoption of SDCs as a means to enhance public safety and COVID-19 patient care efficiency (including consistency and satisfaction) and minimize health care expenses becomes increasingly essential when moving towards value-based sales and reimbursements away from service charges. It is wise to introduce innovative financial mechanisms to pay for diabetes that cannot be covered by fiscally limited private and university medical centers. We foresee potential clinical SDCs to be made up of a well-defined framework and six areas or foundations that act as basic guiding principles for the advancement of diabetes treatment skills that can be easily illustrated by stakeholders, including insurance facilities, consumers, payers and government departments

Environmental effects of ozone depletion, UV radiation and interactions with climate change : UNEP Environmental Effects Assessment Panel, update 2017

Peer reviewe

Development and Validation of 96-Microwell-Based Spectrophotometric and High-Performance Liquid Chromatography with Fluorescence Detection Methods with High Throughput for Quantitation of Duvelisib and Seliciclib in Their Bulk Forms and Capsules

The Food and Drug Administration (FDA) has approved duvelisib (DUV) for managing follicular lymphoma, small lymphocytic lymphoma, and relapsed or refractory chronic lymphocytic leukemia. Seliciclib (SEL) is a candidate drug for these cancers, neurodegenerative disorders, renal diseases, several viral infections, and chronic inflammation disorders. This work describes the development and validation of a 96-microwell-based spectrophotometric method (MW-SPM) and a high-performance liquid chromatography with fluorescence detection method (HPLC-FD) for the quantitation of DUV and SEL in their bulk forms and capsules. The MW-SPM is based on the formation of colored charge transfer complexes (CTCs) as products for the reactions of DUV and SEL, as n-electron donors, with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), as a π-electron acceptor. The absorption intensity of the CTCs was measured by using an absorbance plate reader at 450 nm. The stoichiometric ratios of DUV:DDQ and SEL:DDQ were 1:1 and 1:2, respectively, and accordingly the reaction mechanisms were postulated. The HPLC-FD involved the chromatographic separation of DUV and SEL on a Hypersil™ Phenyl HPLC column (250 mm length × 4.6 mm i.d., 5 μm particle diameter) with a mobile phase composed of acetonitrile:acetate buffer, pH 4.5 (35:65, v/v) at a flow rate of 2.2 mL/min. DUV and SEL were detected at 370 nm after excitation at 280 nm. SEL was used as an internal standard (IS) for quantitation of DUV, and DUV was used as an IS for quantitation of SEL. Both MW-SPM and HPLC-FD were validated according to the guidelines of the International Council for Harmonization (ICH) for validation of analytical procedures. The linear ranges for both DUV and SEL were 14.52–200 µg/well (100 µL) and 0.12–3.2 µg/mL for MW-SPM and HPLC-FD, respectively. LOD values in MW-SPM for DUV and SEL were 4.4 and 3.17 µg/well, respectively; however, those for HPLC-FD were 0.03 and 0.05 µg/mL, respectively. The accuracy and precision of both methods were confirmed as the recovery values were ≥98.5% and the values of relative standard deviations (RSD) were ≤2.41%. Both methods were satisfactorily applied to the quantitation of DUV and SEL in their capsules; the mean recovery values were ≥99.2%. Both methods have simple procedures and high analytical throughput. Moreover, they consume a small volume of organic solvent; thus, they are economic and eco-friendly. Accordingly, the methods are valuable for routine use in quality control (QC) laboratories for quantitation of DUV and SEL in their bulk forms and capsules

Development and Validation of 96-Microwell-Based Spectrophotometric and High-Performance Liquid Chromatography with Fluorescence Detection Methods with High Throughput for Quantitation of Duvelisib and Seliciclib in Their Bulk Forms and Capsules

The Food and Drug Administration (FDA) has approved duvelisib (DUV) for managing follicular lymphoma, small lymphocytic lymphoma, and relapsed or refractory chronic lymphocytic leukemia. Seliciclib (SEL) is a candidate drug for these cancers, neurodegenerative disorders, renal diseases, several viral infections, and chronic inflammation disorders. This work describes the development and validation of a 96-microwell-based spectrophotometric method (MW-SPM) and a high-performance liquid chromatography with fluorescence detection method (HPLC-FD) for the quantitation of DUV and SEL in their bulk forms and capsules. The MW-SPM is based on the formation of colored charge transfer complexes (CTCs) as products for the reactions of DUV and SEL, as n-electron donors, with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), as a π-electron acceptor. The absorption intensity of the CTCs was measured by using an absorbance plate reader at 450 nm. The stoichiometric ratios of DUV:DDQ and SEL:DDQ were 1:1 and 1:2, respectively, and accordingly the reaction mechanisms were postulated. The HPLC-FD involved the chromatographic separation of DUV and SEL on a Hypersil™ Phenyl HPLC column (250 mm length × 4.6 mm i.d., 5 μm particle diameter) with a mobile phase composed of acetonitrile:acetate buffer, pH 4.5 (35:65, v/v) at a flow rate of 2.2 mL/min. DUV and SEL were detected at 370 nm after excitation at 280 nm. SEL was used as an internal standard (IS) for quantitation of DUV, and DUV was used as an IS for quantitation of SEL. Both MW-SPM and HPLC-FD were validated according to the guidelines of the International Council for Harmonization (ICH) for validation of analytical procedures. The linear ranges for both DUV and SEL were 14.52–200 µg/well (100 µL) and 0.12–3.2 µg/mL for MW-SPM and HPLC-FD, respectively. LOD values in MW-SPM for DUV and SEL were 4.4 and 3.17 µg/well, respectively; however, those for HPLC-FD were 0.03 and 0.05 µg/mL, respectively. The accuracy and precision of both methods were confirmed as the recovery values were ≥98.5% and the values of relative standard deviations (RSD) were ≤2.41%. Both methods were satisfactorily applied to the quantitation of DUV and SEL in their capsules; the mean recovery values were ≥99.2%. Both methods have simple procedures and high analytical throughput. Moreover, they consume a small volume of organic solvent; thus, they are economic and eco-friendly. Accordingly, the methods are valuable for routine use in quality control (QC) laboratories for quantitation of DUV and SEL in their bulk forms and capsules