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1.
Chem Sci ; 15(6): 2019-2025, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38332831

ABSTRACT

Solid-gas reactions and in situ powder X-ray diffraction investigations of trinuclear silver complexes {[3,4,5-(CF3)3Pz]Ag}3 and {[4-Br-3,5-(CF3)2Pz]Ag}3 supported by highly fluorinated pyrazolates reveal that they undergo intricate ethylene-triggered structural transformations in the solid-state producing dinuclear silver-ethylene adducts. Despite the complexity, the chemistry is reversible producing precursor trimers with the loss of ethylene. Less reactive {[3,5-(CF3)2Pz]Ag}3 under ethylene pressure and low-temperature conditions stops at an unusual silver-ethylene complex in the trinuclear state, which could serve as a model for intermediates likely present in more common trimer-dimer reorganizations described above. Complete structural data of three novel silver-ethylene complexes are presented together with a thorough computational analysis of the mechanism.

2.
Chemistry ; 29(65): e202302136, 2023 Nov 21.
Article in English | MEDLINE | ID: mdl-37572364

ABSTRACT

A Mn(II) salt and A+ CN- under anaerobic conditions react to form 2-D and 3-D extended structured compounds of Am MnII n (CN)m+2n stoichiometry. Here, the creation and characterization of this large family of compounds, for example AMnII 3 (CN)7 , A2 MnII 3 (CN)8 , A2 MnII 5 (CN)12 , A3 MnII 5 (CN)13 , and A2 MnII [MnII (CN)6 ], where A represents alkali and tetraalkylammonium cations, is reviewed. Cs2 MnII [MnII (CN)6 ] has the typical Prussian blue face centered cubic unit cell. However, the other alkali salts are monoclinic or rhombohedral. This is in accord with smaller alkali cation radii creating void space that is minimized by increasing the van der Waals stabilization energy by reducing ∠Mn-N≡C, which, strengthens the magnetic coupling and increases the magnetic ordering temperatures. This is attributed to the non-rigidity of the framework structure due the significant ionic character associated with the high-spin MnII sites. For larger tetraalkylammonium cations, the high-spin Mn sites lack sufficient electrostatic A+ ⋅⋅⋅NC stabilization and form unexpected 4- and 5-coordinated Mn sites within a flexible, extended framework around the cation; hence, the size, shape, and charge of the cation dictate the unprecedented stoichio-metry and unpredictable cation adaptive structures. Antiferromagnetic coupling between adjacent MnII sites leads to ferrimagnetic ordering, but in some cases antiferromagnetic coupling of ferrimagnetic layers are compensated and synthetic antiferromagnets are observed. The magnetic ordering temperatures for ferrimagnetic A2 MnII [MnII (CN)6 ] with both octahedral high- and low-spin MnII sites increase with decreasing ∠Mn-N≡C. The crystal structures for all of the extended structured materials were obtained by powder diffraction.

3.
Breast ; 66: 69-76, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36194950

ABSTRACT

BACKGROUND: Paclitaxel is commonly used as first-line chemotherapy for HER2-negative metastatic breast cancer (MBC) patients. However, with response rates of 21.5-53.7% and significant risk of peripheral neuropathy, there is need for better chemotherapy. PATIENTS AND METHODS: This open-label phase II/III trial randomised HER2-negative MBC patients 1:1 to either 6 cycles of three-weekly cabazitaxel (25 mg/m2), or, weekly paclitaxel (80 mg/m2) over 18 weeks. The primary endpoint was progression free survival (PFS). Secondary endpoints included objective response rate (ORR), time to response (TTR), overall survival (OS), safety and tolerability and quality of life (QoL). RESULTS: 158 patients were recruited. Comparing cabazitaxel to paclitaxel, median PFS was 6.7 vs 5.8 months (HR 0.87; 80%CI 0.70-1.08, P = 0.4). There was no difference in median OS (20.6 vs 18.2 months, HR 1.00; 95%CI 0.69-1.45, P = 0.99), ORR (41.8% vs 36.7%) or TTR (HR 1.09; 95%CI 0.68-1.75, P = 0.7). Grade ≥3 adverse events occurred in 41.8% on cabazitaxel and 46.8% on paclitaxel; the most common being neutropenia (16.5%) and febrile neutropenia (12.7%) cabazitaxel and neutropenia (8.9%) and lung infection (7.6%) paclitaxel. Peripheral neuropathy of any grade occurred in 54.5% paclitaxel vs 16.5% cabazitaxel. Mean EQ-5D-5L single index utility score (+0.05; 95%CI 0.004-0.09, P = 0.03) and visual analogue scale score (+7.7; 95%CI 3.1-12.3, P = 0.001) were higher in cabazitaxel vs paclitaxel. CONCLUSIONS: Three-weekly cabazitaxel in HER2-negative MBC does not significantly improve PFS compared to weekly paclitaxel, although it has a lower risk of peripheral neuropathy with better patient reported QoL outcomes. It is well tolerated and requires fewer hospital visits.


Subject(s)
Breast Neoplasms , Neutropenia , Humans , Female , Breast Neoplasms/pathology , Paclitaxel , Quality of Life , Receptor, ErbB-2 , Neutropenia/chemically induced , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Treatment Outcome
4.
Molecules ; 27(5)2022 Feb 23.
Article in English | MEDLINE | ID: mdl-35268604

ABSTRACT

The increase in the number of bacteria that are resistant to multiple antibiotics poses a serious clinical problem that threatens the health of humans worldwide. Nadifloxacin (1) is a highly potent antibacterial agent with broad-spectrum activity. However, its poor aqueous solubility has limited its use to topical applications. To increase its solubility, it was glycosylated herein to form a range of trans-linked (3a-e) and cis-linked (7a,b) glycosides, each of which was prepared and purified to afford single anomers. The seven glycoside derivatives (3a-e, 7a,b) were examined for potency against eight strains of S. aureus, four of which were methicillin-resistant. Although less potent than free nadifloxacin (1), the α-L-arabinofuransoside (3a) was effective against all strains that were tested (minimum inhibitory concentrations of 1-8 µg/mL compared to 0.1-0.25 µg/mL for nadifloxacin), demonstrating the potential of this glycoside as an antibacterial agent. Estimation of Log P as well as observations made during preparation of these compounds reveal that the solubilities of the glycosides were greatly improved compared with nadifloxacin (1), raising the prospect of its use in oral applications.


Subject(s)
Fluoroquinolones , Quinolizines
5.
Angew Chem Int Ed Engl ; 60(52): 27184-27188, 2021 Dec 20.
Article in English | MEDLINE | ID: mdl-34670001

ABSTRACT

Purification of C2 H4 from an C2 H4 /C2 H6 mixture is one of the most challenging separation processes, which is achieved mainly through energy-intensive, cryogenic distillation in industry. Sustainable, non-distillation methods are highly desired as alternatives. We discovered that the fluorinated bis(pyrazolyl)borate ligand supported copper(I) complex {[(CF3 )2 Bp]Cu}3 has features very desirable in an olefin-paraffin separation material. It binds ethylene exclusively over ethane generating [(CF3 )2 Bp]Cu(C2 H4 ). This molecular compound exhibits extremely high and record ideal adsorbed solution theory (IAST) C2 H4 /C2 H6 gas separation selectivity, affording high purity (>99.5 %) ethylene that can be readily desorbed from separation columns. In-situ PXRD provides a "live" picture of the reversible conversion between [(CF3 )2 Bp]Cu(C2 H4 ) and the ethylene-free sorbent in the solid-state, driven by the presence or removal of C2 H4 . Molecular structures of trinuclear {[(CF3 )2 Bp]Cu}3 and mononuclear [(CF3 )2 Bp]Cu(C2 H4 ) are also presented.

6.
Dalton Trans ; 50(32): 11228-11242, 2021 Aug 28.
Article in English | MEDLINE | ID: mdl-34338700

ABSTRACT

To identify the genesis of the differing magnetic behaviors for the ferro- (FO) and metamagnetic (MM) polymorphs of [FeCp*2][TCNQ] (Cp* = pentamethylcyclopentadienide; TCNQ = 7,7,8,8-tetracyano-p-quinodimethane) the low temperature (18 ± 1 K) structures of each polymorph were determined from high-resolution synchrotron powder diffraction data. Each polymorph possesses chains of alternating S = 1/2 [FeCp*2]˙+ cations and S = 1/2 [TCNQ]˙+, but with differing relative orientations. These as well as an additional paramagnetic polymorph do not thermally interconvert. In addition, the room and low (<70 ± 10 K) temperature structures of the MM polymorph, MMRT and MMLT, respectively, differ from that previously reported at 167 K (-106 °C) MM structure, and no evidence of either phase transition was previously noted even from the magnetic data. This transition temperature and enthalpy of this phase transition for MMRT⇌MM was determined to be 226.5 ± 0.4 K (-46.7 ± 0.4 °C) and 0.68 ± 0.04 kJ mol-1 upon warming, respectively, from differential calorimetry studies (DSC). All three MM phases are triclinic (P1[combining macron]) with the room temperature phase having a doubled unit cell relative to the other two. The lower temperature phase transition involves a small rearrangement of the molecular ions and shift in lattice parameters. These three MM and FO polymorphs have been characterized and form extended 1-D chains with alternating S = 1/2 [FeCp*2]˙+ cations, and S = 1/2 [TCNQ]˙- anions, whereas the fifth, paramagnetic (P) polymorph possesses S = 0 π-[TCNQ]22- dimers. At 18 ± 1 K the intrachain FeFe separations are 10.738(2) and 10.439(3) Å for the FO and MMLT polymorphs, respectively. The key structural differences between FO and MMLT at 18 ± 1 K are the 10% shorter interchain NN and the 2.8% shorter intrachain FeFe separation present for MMLT. Computational analysis of all nearest-neighbor spin couplings for the 18 K structures of FO and MMLT indicates that the intrachain [FeCp*2]˙+[TCNQ]˙- spin couplings (H = -2Si·Sj) are the strongest (4.95 and 6.5 cm-1 for FO and MMLT, respectively), as previously hypothesized, and are ferromagnetic due to their S = 1/2 spins residing in orthogonal orbitals. The change in relative [TCNQ]˙-[TCNQ]˙- orientations leads to a computed change from the ferromagnetic interaction (0.2 cm-1) for FO to an antiferromagnetic interaction (-0.1 cm-1) for MMLT in accord with its observed antiferromagnetic ground state. Hence, the magnetic ground state cannot be solely described by the dominant magnetic interactions.

7.
Afr J Reprod Health ; 25(3): 14-20, 2021 Jun.
Article in English | MEDLINE | ID: mdl-37585837

ABSTRACT

This paper describes volume trends of non-subsidised contraceptive commodities (NSCC) in Kenya between 2016-2019. We hypothesise that if non-subsidised contraceptive commodities volumes increased at times of public sector shortage then then we might hope for a similar response should public sector supplies reduce in response to an expected decline in donor funding. We find that non-subsidised contraceptive commodities contribute only 2% of total volume, and that these volumes are dominated by emergency contraceptives (EC) and combined oral contraceptives (COC). EC and COC volumes increased significantly during the 2017 nurses' strike, but not during those periods when the Kenya Medical Supplies Authority (KEMSA) was out of stock. Increases in NSCC volumes were not of sufficient size, however, to compensate for the decline in public sector volumes. In short it appears that the market for NSCC is small and constrained. We recommend that further research is needed to understand why distributors of NSCCs are not able to take advantage of continuing public sector supply shortages.

8.
Lancet Oncol ; 21(10): 1296-1308, 2020 10.
Article in English | MEDLINE | ID: mdl-32919527

ABSTRACT

BACKGROUND: Circulating tumour DNA (ctDNA) testing might provide a current assessment of the genomic profile of advanced cancer, without the need to repeat tumour biopsy. We aimed to assess the accuracy of ctDNA testing in advanced breast cancer and the ability of ctDNA testing to select patients for mutation-directed therapy. METHODS: We did an open-label, multicohort, phase 2a, platform trial of ctDNA testing in 18 UK hospitals. Participants were women (aged ≥18 years) with histologically confirmed advanced breast cancer and an Eastern Cooperative Oncology Group performance status 0-2. Patients had completed at least one previous line of treatment for advanced breast cancer or relapsed within 12 months of neoadjuvant or adjuvant chemotherapy. Patients were recruited into four parallel treatment cohorts matched to mutations identified in ctDNA: cohort A comprised patients with ESR1 mutations (treated with intramuscular extended-dose fulvestrant 500 mg); cohort B comprised patients with HER2 mutations (treated with oral neratinib 240 mg, and if oestrogen receptor-positive with intramuscular standard-dose fulvestrant); cohort C comprised patients with AKT1 mutations and oestrogen receptor-positive cancer (treated with oral capivasertib 400 mg plus intramuscular standard-dose fulvestrant); and cohort D comprised patients with AKT1 mutations and oestrogen receptor-negative cancer or PTEN mutation (treated with oral capivasertib 480 mg). Each cohort had a primary endpoint of confirmed objective response rate. For cohort A, 13 or more responses among 78 evaluable patients were required to infer activity and three or more among 16 were required for cohorts B, C, and D. Recruitment to all cohorts is complete and long-term follow-up is ongoing. This trial is registered with ClinicalTrials.gov, NCT03182634; the European Clinical Trials database, EudraCT2015-003735-36; and the ISRCTN registry, ISRCTN16945804. FINDINGS: Between Dec 21, 2016, and April 26, 2019, 1051 patients registered for the study, with ctDNA results available for 1034 patients. Agreement between ctDNA digital PCR and targeted sequencing was 96-99% (n=800, kappa 0·89-0·93). Sensitivity of digital PCR ctDNA testing for mutations identified in tissue sequencing was 93% (95% CI 83-98) overall and 98% (87-100) with contemporaneous biopsies. In all cohorts, combined median follow-up was 14·4 months (IQR 7·0-23·7). Cohorts B and C met or exceeded the target number of responses, with five (25% [95% CI 9-49]) of 20 patients in cohort B and four (22% [6-48]) of 18 patients in cohort C having a response. Cohorts A and D did not reach the target number of responses, with six (8% [95% CI 3-17]) of 74 in cohort A and two (11% [1-33]) of 19 patients in cohort D having a response. The most common grade 3-4 adverse events were raised gamma-glutamyltransferase (13 [16%] of 80 patients; cohort A); diarrhoea (four [25%] of 20; cohort B); fatigue (four [22%] of 18; cohort C); and rash (five [26%] of 19; cohort D). 17 serious adverse reactions occurred in 11 patients, and there was one treatment-related death caused by grade 4 dyspnoea (in cohort C). INTERPRETATION: ctDNA testing offers accurate, rapid genotyping that enables the selection of mutation-directed therapies for patients with breast cancer, with sufficient clinical validity for adoption into routine clinical practice. Our results demonstrate clinically relevant activity of targeted therapies against rare HER2 and AKT1 mutations, confirming these mutations could be targetable for breast cancer treatment. FUNDING: Cancer Research UK, AstraZeneca, and Puma Biotechnology.


Subject(s)
Biomarkers, Tumor/genetics , Breast Neoplasms/drug therapy , Circulating Tumor DNA/blood , Molecular Targeted Therapy , Adult , Aged , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Estrogen Receptor alpha/antagonists & inhibitors , Estrogen Receptor alpha/genetics , Female , Fulvestrant/therapeutic use , Genotype , Humans , Middle Aged , Mutation , PTEN Phosphohydrolase/genetics , Prospective Studies , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Proto-Oncogene Proteins c-akt/genetics , Pyrimidines/therapeutic use , Pyrroles/therapeutic use , Quinolines/therapeutic use , Receptor, ErbB-2/genetics , Receptors, Estrogen/antagonists & inhibitors , Receptors, Estrogen/genetics , Receptors, Estrogen/metabolism , Treatment Outcome
9.
Bull World Health Organ ; 98(7): 467-474, 2020 Jul 01.
Article in English | MEDLINE | ID: mdl-32742032

ABSTRACT

OBJECTIVE: To assess sales of anti-cancer medicines in the 2017 World Health Organization's WHO Model list of essential medicines in China, Indonesia, Kazakhstan, Malaysia, Philippines and Thailand from 2007 (2008 for Kazakhstan and Malaysia) to 2017. METHODS: We extracted sales volume data for 39 anti-cancer medicines from the IQVIA database. We divided the total quantity sold by the reference defined daily dose to estimate the total number of defined daily doses sold, per country per year, for three types of anti-cancer therapies (traditional chemotherapy, targeted therapy and endocrine therapy). We adjusted these data by the number of new cancer cases in each country for each year. FINDINGS: We observed an increase in sales across all types of anti-cancer therapies in all countries. The largest number of defined daily doses of traditional chemotherapy per new cancer case was sold in Thailand; however, the largest relative increase per new cancer case occurred in Indonesia (9.48-fold). The largest absolute and relative increases in sales of defined daily doses of targeted therapies per new cancer case occurred in Kazakhstan. Malaysia sold the largest number of adjusted defined daily doses of endocrine therapies in 2017, while China and Indonesia more than doubled their adjusted sales volumes between 2007 and 2017. CONCLUSION: The use of sales data can fill an important knowledge gap in the use of anti-cancer medicines, particularly during periods of insurance coverage expansion. Combined with other data, sales volume data can help to monitor efforts to improve equitable access to essential medicines.


Subject(s)
Antineoplastic Agents/economics , Drug Utilization/economics , Drug Utilization/statistics & numerical data , Neoplasms/drug therapy , Antineoplastic Agents/therapeutic use , China/epidemiology , Commerce , Databases, Factual , Humans , Indonesia/epidemiology , Kazakhstan/epidemiology , Malaysia/epidemiology , Neoplasms/economics , Neoplasms/epidemiology , Philippines/epidemiology , Thailand/epidemiology
10.
Br J Cancer ; 123(4): 525-533, 2020 08.
Article in English | MEDLINE | ID: mdl-32523090

ABSTRACT

BACKGROUND: This phase 1 study examined the safety, maximum-tolerated dose (MTD) and antitumour activity of E7449, a novel PARP 1/2 and tankyrase 1/2 inhibitor. METHODS: E7449 was orally administered once daily in 28-day cycles to patients with advanced solid tumours (50-800-mg doses). Archival tumour samples from consenting patients were evaluated for the expression of 414 genes in a biomarker panel (2X-121 drug-response predictor [DRP]) found to be predictive of the response to E7449 in cell lines. RESULTS: Forty-one patients were enrolled (13 pancreatic, 5 ovarian, 4 each with breast, lung or colorectal cancer and 11 with other tumour types). The most common grade ≥3 treatment-related adverse event was fatigue (n = 7, 17.1%). Five patients experienced a dose-limiting toxicity (fatigue, n = 4, 800 mg; anaphylaxis, n = 1, 600 mg) for an MTD of 600 mg. E7449 exhibited antitumour activity in solid tumours, including 2 partial responses (PRs), and stable disease (SD) in 13 patients, which was durable (>23 weeks) for 8 patients. In 13 patients, the 2X-121 DRP identified those achieving PR and durable SD. E7449 showed good tolerability, promising antitumour activity and significant concentration-dependent PARP inhibition following 50-800-mg oral dosing. CONCLUSION: The results support further clinical investigation of E7449 and its associated biomarker 2X-121 DRP. CLINICAL TRIAL REGISTRATION: www.ClinicalTrials.gov code: NCT01618136.


Subject(s)
Biomarkers, Tumor/genetics , Isoquinolines/administration & dosage , Neoplasms/drug therapy , Poly(ADP-ribose) Polymerase Inhibitors/administration & dosage , Quinazolinones/administration & dosage , Administration, Oral , Adult , Aged , Azo Compounds , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Drug Administration Schedule , Female , Gene Expression Regulation, Neoplastic/drug effects , Humans , Isoquinolines/adverse effects , Isoquinolines/pharmacology , Male , Maximum Tolerated Dose , Middle Aged , Neoplasms/genetics , Poly(ADP-ribose) Polymerase Inhibitors/adverse effects , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Quinazolinones/adverse effects , Quinazolinones/pharmacology , Survival Analysis , Treatment Outcome
11.
Chemistry ; 26(67): 15565-15572, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32427369

ABSTRACT

The reactions of MnII (O2 CCH3 )2 with NEt3 Me+ CN- and NEt2 Me2 + CN- form (NEt3 Me)2 MnII 5 (CN)12 (1) and (NEt2 Me2 )2 MnII 5 (CN)12 (2), respectively. Structure model-building and Rietveld refinement of high-resolution synchrotron powder diffraction data revealed a cubic [a=24.0093 Š(1), 23.8804 Š(2)] 3D extended structural motif with adjacent tetrahedral and octahedral MnII sites in a 3:2 ratio. Each tetrahedral MnII site is surrounded by four low-spin octahedral MnII sites, and each octahedral MnII site is surrounded by six high-spin tetrahedral MnII sites; adjacent sites are antiferromagnetically coupled in 3D. Compensation does not occur, and magnetic ordering as a ferrimagnet is observed at Tc =13 K for 2 based on the temperature at which remnant magnetization, Mr (T)→0. The hysteresis has an unusual constricted shape with inflection points around 50 and 1.2 kOe with a 5 K coercivity of 16 Oe and remnant magnetization, Mr , of 2050 emuOe mol-1 . The unusual structure and stoichiometry are attributed to the very ionic nature of the high-spin N-bonded MnII ion, which enables the maximization of the attractive van der Waals interactions through minimization of void space via a reduced ∠ MnNC. This results in an additional example of the Ax MnII y (CN)x+2y (x=0, y=1; x=1, y=3; x=2, y=1; x=2, y=2; x=2, y=3; x=3, y=5; and x=4, y=1) family of compounds possessing an unprecedented stoichiometry and lattice motif that are cation adaptive structured materials.

12.
J Am Chem Soc ; 142(15): 7168-7178, 2020 Apr 15.
Article in English | MEDLINE | ID: mdl-32216316

ABSTRACT

Understanding the electric dipole switching in multiferroic materials requires deep insight of the atomic-scale local structure evolution to reveal the ferroelectric mechanism, which remains unclear and lacks a solid experimental indicator in high-pressure prepared LiNbO3-type polar magnets. Here, we report the discovery of Zn-ion splitting in LiNbO3-type Zn2FeNbO6 established by multiple diffraction techniques. The coexistence of a high-temperature paraelectric-like phase in the polar Zn2FeNbO6 lattice motivated us to revisit other high-pressure prepared LiNbO3-type A2BB'O6 compounds. The A-site atomic splitting (∼1.0-1.2 Šbetween the split-atom pair) in B/B'-mixed Zn2FeTaO6 and O/N-mixed ZnTaO2N is verified by both powder X-ray diffraction structural refinements and high angle annular dark field scanning transmission electron microscopy images, but is absent in single-B-site ZnSnO3. Theoretical calculations are in good agreement with experimental results and suggest that this kind of A-site splitting also exists in the B-site mixed Mn-analogues, Mn2FeMO6 (M = Nb, Ta) and anion-mixed MnTaO2N, where the smaller A-site splitting (∼0.2 Šatomic displacement) is attributed to magnetic interactions and bonding between A and B cations. These findings reveal universal A-site splitting in LiNbO3-type structures with mixed multivalent B/B', or anionic sites, and the splitting-atomic displacement can be strongly suppressed by magnetic interactions and/or hybridization of valence bands between d electrons of the A- and B-site cations.

13.
J Pharm Policy Pract ; 12: 18, 2019.
Article in English | MEDLINE | ID: mdl-31417682

ABSTRACT

OBJECTIVES: To describe changes in the private market for selected originators, branded generics ('similares'), and generic products during the 10 years following passage of the Brazilian Generics Law. METHODS: We analyzed longitudinal data collected by IQVIA® on quarterly sales by wholesalers to retail pharmacies in Brazil from 1998 through 2010, grouped by originators, branded generics, and generic products in three therapeutic classes (antibiotics, antidiabetics, and antihypertensives). Outcomes included market share (proportion of the total private market volume), sales volume per capita, prices and number of manufacturers by group. RESULTS: In the private market share, generics became dominant in each therapeutic class but the speed of uptake varied. Originators consistently lost most market share while branded generics varied over time. By the end of the study period, generics were the most sold product type in all classes, followed by branded generics. The number of generic manufacturers increased in all classes, while branded generics increased just after the policy but then decreased slowly through the end of 2010. For approximately 50% of the antibiotics analyzed, branded generics and generics had lower prices than originators. For antidiabetics, branded generic and generic prices were quite similar during the period analyzed. Price trends for the various subclasses of antihypertensive exhibited very different patterns over time. CONCLUSION: Sales of branded generics and originators decreased substantially in the three therapeutic classes analysed following the introduction of the generics policy in Brazil, but the time to market dominance of generics varied by class.

14.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 4): 489-491, 2019 Apr 01.
Article in English | MEDLINE | ID: mdl-31161062

ABSTRACT

We report a new polymorph of acridine, C13H9N, denoted form IX, obtained as thin needles by slow evaporation of a toluene solution. The structure was solved and refined from powder X-ray data. The structures of five unsolvated forms were previously known, but this is only the second with one mol-ecule in the asymmetric unit. The melting point [differential scanning calorimetry (DSC) onset] and heat of fusion are 108.8 (3) °C and 19.2 (4) kJ mol-1, respectively.

15.
BMJ Glob Health ; 4(1): e001241, 2019.
Article in English | MEDLINE | ID: mdl-30899565

ABSTRACT

INTRODUCTION: Understanding patterns of antibiotic consumption is essential to ensure access to appropriate antibiotics when needed and to minimise overuse, which can lead to antibiotic resistance. We aimed to describe changes in global antibiotic consumption between 2011 and 2015. METHODS: We analysed wholesale data on total antibiotic sales and antibiotics sold as child-appropriate formulations (CAFs), stratified by country income level (low/middle-income and high-income countries (LMICs and HICs)). The volume of antibiotics sold per year was recorded for 36 LMICs and 39 HICs, measured in standard units (SU: 1 SU is equivalent to a single tablet, capsule or 5 mL ampoule/vial/oral suspension) and SU per person, overall and as CAFs. Changes over time were quantified as percentage changes and compound annual growth rates in consumption per person. Analyses were conducted separately for total sales, sales of antibiotics in the Access and Watch groups of the WHO's Essential Medicines List for children 2017, for amoxicillin and amoxicillin with clavulanic acid. RESULTS: Antibiotic consumption increased slightly between 2011 and 2015, from 6.85×1010 SU to 7.44×1010 SU overall and from 1.66×1010 SU to 1.78×1010 SU for CAFs. However, trends differed between countries and for specific antibiotics; for example, consumption of amoxicillin as CAFs changed little in LMICs and HICs, but that of amoxicillin with clavulanic acid increased by 6.8% per year in LMICs and decreased by 1.0% per year in HICs. CONCLUSIONS: As measured in standard units in sales data, the rate of increase in global antibiotic consumption may be slowing. However, the trends appear to differ between countries and drugs. In the absence of routine surveillance of antibiotic use in many countries, these data provide important indicators of trends in consumption which should be confirmed in national and local studies of prescribing.

16.
Chemistry ; 25(7): 1752-1757, 2019 Feb 01.
Article in English | MEDLINE | ID: mdl-30286266

ABSTRACT

The reaction of MnII (O2 CMe)2 and NaCN or LiCN in water forms a light green insoluble material. Structural solution and Rietveld refinement of high-resolution synchrotron powder diffraction data for this unprecedented, complicated compound of previously unknown composition revealed a new alkali-free ordered structural motif with [MnII 4 (µ3 -OH)4 ]4+ cubes and octahedral [MnII (CN)6 ]4- ions interconnected in 3D by MnII -N≡C-MnII linkages. The composition is {[MnII (OH2 )3 ][MnII (OH2 )]3 }(µ3 -OH)4 ][MnII (µ-CN)2 (CN)4 ]⋅H2 O=[MnII 4 (µ3 -OH)4 (OH2 )6 ][MnII (µ-CN)2 (CN)4 ]⋅H2 O, which is further simplified to [Mn4 (OH)4 ][Mn(CN)6 ](OH2 )7 (1). 1 has four high-spin (S=5/2) MnII sites that are antiferromagnetically coupled within the cube and are antiferromagnetically coupled to six low-spin (S=1/2) octahedral [MnII (CN)6 ]4- ions. Above 40 K the magnetic susceptibility, χ(T), can be fitted to the Curie-Weiss expression, χ ∝(T-θ)-1 , with θ=-13.4 K, indicative of significant antiferromagnetic coupling and 1 orders as an antiferromagnet at Tc =7.8 K.

17.
Eur J Med Chem ; 162: 51-58, 2019 Jan 15.
Article in English | MEDLINE | ID: mdl-30408748

ABSTRACT

There is an ongoing urgent need for new targeted antibacterial compounds with novel mechanisms of action for the treatment of infections caused by bacteria that are resistant to currently available materials. Since the expression of glycosidase enzymes within bacteria is unequally distributed, glycoside derivatives of antibacterial agents offer potential as targeted prodrugs for bacterial infections. Herein we report the synthesis and characterisation of four α-D-glycopyranosides and three ß-D-glycopyranosides of the broad antibacterial agent triclosan, in generally good synthetic yields, and with excellent purities. Each glycoside was analysed to determine its ability to inhibit the growth of a wide range of Gram-negative and Gram-positive organisms, including many of clinical significance. All of the triclosan glycosides that were synthesized demonstrated antibacterial activity against many of the organisms that were examined. For example, ß-galactoside (3a) and α-arabinoside (3c) had MIC values of 0.5 µg/ml for several strains of S. aureus and S. haemolyticus. The triclosan glycosides were also generally found to be more water soluble and much more selective than the underivatized triclosan, making them ideal both for the targeted inhibition of bacterial growth and as agents for the selective recovery of bacteria from mixed cultures. In the latter case, two Bacillus strains could be identified from various strains of Bacillus and Staphylococcus after inoculation onto Nutrient Agar No. 2 with 0.25 µg/ml triclosan-α-D-glucopyranoside (3e). This glucoside may, therefore, be of use for the isolation and identification of the food-poisoning organism Bacillus cereus.


Subject(s)
Anti-Bacterial Agents/pharmacology , Triclosan/analogs & derivatives , Anti-Bacterial Agents/chemical synthesis , Anti-Infective Agents, Local , Bacteria/drug effects , Bacterial Infections/drug therapy , Glucosides , Microbial Sensitivity Tests , Triclosan/chemical synthesis , Triclosan/pharmacology
18.
Chemistry ; 25(17): 4373-4378, 2019 Mar 21.
Article in English | MEDLINE | ID: mdl-30499153

ABSTRACT

Treating deuterohemin, chloro(deuteroporphyrinato)iron(III), with a non-coordinating base in DMSO/methanol allows for the isolation of [(deuteroporphyrinato)iron(III)]2 , deuterohematin anhydride (DHA), an analogue of malaria pigment, the natural product of heme detoxification by malaria. The structure of DHA obtained from this solvent system has been solved by X-ray powder diffraction analysis and displays many similarities, yet important structural differences, to malaria pigment. Most notably, a water molecule of solvation occupies a notch created by the propionate side chains and stabilizes a markedly bent propionate ligand coordinated with a long Fe-O bond, and a carboxylate cluster associated with water molecules is generated. Together, these features account for its increased solubility and more open structure, with an increased porphyrin-porphyrin separation. The IR spectroscopic signature associated with this structure also accounts for the strong IR band at 1587 cm-1 seen for many amorphous preparations of synthetic malaria pigment, and it is proposed that stabilizing these structures may be a new objective for antimalarial drugs. The important role of the vinyl substituents in this biochemistry is further demonstrated by the structure of deuterohemin obtained by single-crystal X-ray diffraction analysis.

19.
J Am Chem Soc ; 141(2): 911-921, 2019 Jan 16.
Article in English | MEDLINE | ID: mdl-30557002

ABSTRACT

The size of the organic cation dictates both the composition and the extended 3-D structure for hybrid organic/inorganic Prussian blue analogues (PBAs) of A aMnII b(CN) a+2 b (A = cation) stoichiometry. Alkali PBAs are typically cubic with both MC6 and M'N6 octahedral coordination sites and the alkali cation content depends on the M and M' oxidation states. The reaction of MnII(O2CCH3)2 and A+CN- (A = NMe4, NEtMe3) forms a hydrated material of A3MnII5(CN)13 composition. A3MnII5(CN)13 forms a complex, 3-D extended structural motif with octahedral and rarely observed square pyramidal and trigonal bipyramidal MnII sites with a single layer motif of three pentagonal and one triangular fused rings. A complex pattern of MnIICN chains bridge the layers. (NMe4)3MnII5(CN)13 possesses one low-spin octahedral and four high-spin pentacoordinate MnII sites and orders as an antiferromagnet at 11 K due to the layers being bridged and antiferromagnetically coupled by the nonmagnetic cyanides. These are rare examples of intrinsic, chemically prepared and controlled artificial antiferromagnets and have the advantage of having controlled uniform spacing between the layers as they are not physically prepared via deposition methods. A3Mn5(CN)13 (A = NMe4, NEtMe3) along with [NEt4]2MnII3(CN)8, [NEt4]MnII3(CN)7, and Mn(CN)2 form stoichiometrically related A aMnII b(CN) a+2 b ( a = 0, b = 1; a = 2, b = 3; a = 1, b = 3; and a = 3, b = 5) series possessing unprecedented stoichiometries and lattice motifs. These unusual structures and stoichiometries are attributed to the very ionic nature of the high-spin N-bonded MnII ion that enables the maximization of the attractive van der Waals interactions via minimization of void space via a reduced ∠MnNC. This A aMnII b(CN) a+2 b family of compounds are referred to as being cation adaptive in which size and shape dictate both the stoichiometry and structure.

20.
Malar J ; 17(1): 444, 2018 Nov 29.
Article in English | MEDLINE | ID: mdl-30497504

ABSTRACT

BACKGROUND: The steady supply of quality, affordable medicines is a pillar of a functioning health system. In addition to the public sector, the private, mission and not-for-profit sectors often serve a large part of the population in Africa. However, while there is generally systematic recording of public sector supply of medicines, detailed, systematic and reliable national market data including these non-public sectors are not commonly available in most countries in Africa. Understanding the total market is a missing part of the access puzzle: without this information, policy makers and health practitioners are not able to fully measure the impact of interventions, measure access to effective products, or fully evaluate the rational use of medicines. This article reports on a unique innovation which provides routine, national-level data on the total pharmaceuticals market, through a system which can be replicated elsewhere. It demonstrates how national-level market data contribute to the evidence base for policies on access to essential medicines, using the Zambian anti-malarial medicines market as a case study. METHODS: A new, routine national database on pharmaceutical market size and structure was established through a multi-partner collaboration. Information was extracted from import authorizations and allows for information on local manufacture. Data included value and volume of products as well as pack details, manufacturer and importer. The system was continually updated: data for this analysis were extracted for 6 years: 2009-2014 inclusive. Data were analysed using Microsoft Excel and validated against other sources including donor procurement data. Analysis included public and private sector markets. The policy relevance was demonstrated through analysis of four aspects of national policies on access and rational use of malaria medicines: (i) volume of product relative to disease burden; (ii) distribution by sector relative to treatment-seeking; (iii) consistency of products with respect to national policy guidelines; (iv) market concentration as a proxy for security of supply. RESULTS: The system developed provides the first accurate, systematic data on the breakdown of a national pharmaceutical market in an African context. The total value of the anti-malarials market in Zambia, including all sectors, was USD 5.5-6 million. This included 22 different molecules or combinations, produced by 56 different manufacturers, with 142 different permutations of molecule/manufacturer/strength. Such data provide a complementary mechanism to confirm key trends in malaria treatment and control in Zambia: (i) sufficient supply relative to disease burden, (ii) value and volume of the private/non-profit sector; 29%-2% of market value and 17%-2% of market volume (from 2009 to 2014), (iii) dominance of the 3 molecules recommended in the national treatment guidelines; and (iv) an evidence-base for national discussions on medicines quality, security of supply and rationale use. The system extracts information on all medicines and therefore could be used to analyse other therapeutic classes. Data have been used for several policy purposes, notably by ZAMRA to monitor the quality of products in Zambia, monitoring implementation of WHO Resolutions on artemisinin monotherapy as well as monitoring trends in product choice across sectors. CONCLUSION: Routine data are important for researchers and policy makers alike. This study shows how medicines data can be systematically gathered at national level-comprising range, volume and value in the public, private and not-for-profit sectors-to monitor more detailed trends in the market and allows triangulation of supply-side data against other sources. This systematic approach can contribute significantly to support access to medicines, monitor treatment and public health policies and create healthy markets. It can be used to monitor changes between therapeutic areas, for example the impact of improved malaria treatment on the use of antibiotics in the context of anti-microbial resistance monitoring. As data contain commercially confidential information, appropriate safeguards should be put in place to balance public health and commercial interests.


Subject(s)
Antimalarials/supply & distribution , Databases, Factual , Drug Utilization , Malaria/drug therapy , Health Policy , Humans , Zambia
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