Low back pain-related beliefs and likely practice behaviours among final-year cross-discipline health students.

BACKGROUND: Evidence points to clinicians' beliefs and practice behaviours related to low back pain (LBP), which are discordant with contemporary evidence. While interventions to align beliefs and behaviours with evidence among clinicians have demonstrated effectiveness, a more sustainable and cost-effective approach to positively developing workforce capacity in this area may be to target the emerging workforce. The aim of this study was to investigate beliefs and clinical recommendations for LBP, and their alignment to evidence, in Australian university allied health and medical students. METHODS: Final-year students in chiropractic, medicine, occupational therapy, pharmacy and physiotherapy disciplines in three Western Australian universities responded to a survey. Demographic data, LBP-related beliefs data [modified Health Care Providers Pain and Impact Relationship Scale (HC-PAIRS) and the Back Pain Beliefs Questionnaire (BBQ)] and activity, rest and work clinical recommendations for an acute LBP clinical vignette were collected. RESULTS: Six hundred two students completed the survey (response rate 74.6%). Cross-discipline differences in beliefs and clinical recommendations were observed (p > 0.001). Physiotherapy and chiropractic students reported significantly more helpful beliefs compared with the other disciplines, while pharmacy students reported the least helpful beliefs. A greater proportion of chiropractic and physiotherapy students reported guideline-consistent recommendations compared with other disciplines. HC-PAIRS and BBQ scores were strongly associated with clinical recommendations, independent to the discipline of study and prior experience of LBP. CONCLUSIONS: Aligning cross-discipline university curricula with current evidence may provide an opportunity to facilitate translation of this evidence into practice with a focus on a consistent, cross-discipline approach to LBP management.

Therapeutic uses of Aloe L. (Asphodelaceae) in southern Africa.

ETHNOPHARMACOLOGICAL RELEVANCE: The African-Arabian succulent genus Aloe L. (Aloaceae/Asphodelaceae) is represented by approximately 120 infrageneric taxa in southern Africa, including A. ferox Mill., a species long used in commercial natural products. AIMS OF THE STUDY: To assess the documented ethnobotanical knowledge and biocultural value of utility in the genus in southern Africa. MATERIALS AND METHODS: A survey of over 350 multidisciplinary publications was undertaken. RESULTS: Local uses for medicine and wellbeing were identified for over half the species of Aloe occurring in the Flora of Southern Africa region. The most frequently cited medicinal uses were the treatment of infections and internal parasites, digestive ailments and injuries. Numerous species were recorded for their social uses, notably as ingredients in tobacco snuff. CONCLUSION: The exceptional infrageneric diversity of Aloe, and extensive therapeutic uses in southern Africa, indicate its cultural importance in the subcontinent. These factors highlight the need for the conservation of the species as well as their potential as a source of natural products.

The application of non-combinatorial chemistry to lead discovery.

Non-combinatorial chemistry is a powerful technology for the synthesis of large numbers of compounds, with complete control over the properties of those compounds. We have developed a Library Creation, Registration and Automation system (LiCRA), which harnesses an efficient non-combinatorial chemistry design and synthesis engine, together with high-throughput automated purification. This LiCRA system also operates in a closed loop mode for hit-to-lead optimization, and contains an integrated IT system that controls and facilitates all aspects of the operation from design to registration. Quality has been our watchword, from the quality of compound design through to the quality of the products.

Effect of LY287045, a thrombin/trypsin inhibitor, on thrombin and trypsin-induced aortic contraction and relaxation.

The active site tripeptide arginal inhibitor of thrombin, LY287045, was used to study thrombin-induced aortic relaxation and contraction, two responses that differ both pharmacologically and physiologically. Although thrombin (10(-7) M) and trypsin (10(-6) M) were tachyphylactic upon repeated administration, trypsin contracted the aorta following thrombin-induced contraction. LY287045 (10(-7) M) attenuated thrombin-induced vasorelaxation, but not vasoconstriction with -log K(B) of 8.4. LY287045 (10(-7) M) also attenuated vasorelaxation, but not vasoconstriction to trypsin, another serine-protease with a thrombin-like catalytic triad, with similar potency (-log K(B) = 8.6) to that for thrombin. Consistent with these vascular effects, LY287045 inhibited the protease activity of both thrombin and trypsin. To explore further the selective inhibitory effect of LY287045 on protease-induced relaxation, we examined the effect of LY287045 on the nitric oxide and prostacyclin pathways and found that LY287045 did not alter vascular responses mediated by nitric oxide or prostacyclin. Likewise, LY287045 did not exert a direct inhibitory effect on the relaxant protease-activated receptor (PAR) since relaxation to the PAR-2-activating peptide was not blocked. The selective effect of LY287045 to inhibit only protease-induced endothelial-dependent relaxation demonstrated that protease inhibition will not affect all protease responses equally. Furthermore, increases in trypsin and thrombin have been associated with inflammation and angiogenesis. To the extent that these findings suggest that LY287045 exhibit dual protease inhibition of endothelial responses, LY287045 may have specific utility in hypotensive inflammatory diseases and in cancer metastases where both trypsin and thrombin have been implicated as causative agents.

1,2-Disubstituted indole, azaindole and benzimidazole derivatives possessing amine moiety: a novel series of thrombin inhibitors.

A novel series of 1,2-disubstituted indole, azaindole and benzimidazole derivatives possessing an amine moiety was identified as thrombin inhibitors. An indole with basic diamine moieties (12a) was the most potent thrombin inhibitor in the series with Kass= 197 x 10(6) L/mol.

A clinical trial investigating the possible effect of the supine cervical rotatory manipulation and the supine lateral break manipulation in the treatment of mechanical neck pain: a pilot study.

OBJECTIVE: To evaluate the possible effect of the supine cervical rotary manipulation and the supine lateral break manipulation in the treatment of mechanical neck pain, according to subjective and objective clinical findings. BACKGROUND: Delivering a supine lateral break manipulation to the ipsilateral side of an inflamed facet joint(s) that exhibits a lateral flexion fixation may result in pain and/or discomfort to the patient. Thus the proposed alternative is a supine cervical rotary manipulation delivered on the ipsilateral side or a supine lateral break manipulation delivered on the contralateral side of the relevant joint(s). DESIGN: Randomized, comparative clinical trial. SUBJECTS: Two groups of 15 subjects diagnosed with mechanical neck pain. INTERVENTION: The diagnosis of mechanical neck pain and the identification of lateral flexion fixations in the cervical spine were made with conventional clinical evaluation, including motion palpation. Group A received a cervical rotary manipulation(s) on the ipsilateral side of the lateral flexion fixation(s), while group B received a supine lateral break manipulation(s) on the contralateral side of the lateral flexion fixation(s). Subjects received a maximum of 10 treatments over a 4-week treatment period. OUTCOME MEASURES: Both treatment groups were assessed with subjective (Numerical Pain Rating Scale 101, McGill Short-Form Pain Questionnaire and the Canadian Memorial Chiropractic College Neck Disability Index) and objective (cervical range of motion goniometer and algometer) measurement parameters at the initial consultation (before any treatment), the final consultation, and at a 1-month follow-up consultation. Statistical analysis was conducted at a 95% confidence level (alpha =.05) with the non-parametric 2-tailed Wilcoxon signed ranks test, the Mann-Whitney U test, and descriptive statistics. Two-tailed power analysis was conducted after the fact, where a confidence level of 80% (beta =.20) was considered satisfactory. RESULTS: Intragroup analysis indicated a significant difference between the initial consultation data and the final consultation data for the subjective data, indicating an effect. Analysis of the objective data did not reveal any significant difference. Intergroup analysis did not reveal any significant difference between the 2 groups when comparing the data of the initial consultation and the final consultation, indicating that both treatments had a similar or equal effect. Power analysis was not satisfactory for most data, indicating the possibility of many Type II errors. CONCLUSION AND RECOMMENDATIONS: Statistically, the results suggested that both treatments had an effect but that neither group showed a benefit over the other. However, because of the unsatisfactory power of the study, conclusions are to be drawn with caution. Clinical significance supported the statistical outcomes where it was suggested that both treatments had an effect and that neither treatment had a greater effect. A larger sample size and the inclusion of a placebo group is recommended to reveal true treatment outcomes and trends.

Diamino benzo[b]thiophene derivatives as a novel class of active site directed thrombin inhibitors. Part 6: further focus on the contracted C4'-side chain analogues.

Novel benzo[b]thiophene diamine thrombin inhibitors were investigated, focusing on a contracted C4'-side chain series. SAR studies identified compounds with either a pyrrolidino or morpholino group as potent, active site directed thrombin inhibitors when the amino group was connected to the C3-phenyl ring with a methylene linker at the C4' position of the phenyl ring.

The crystal structures of human alpha-thrombin complexed with active site-directed diamino benzo[b]thiophene derivatives: a binding mode for a structurally novel class of inhibitors.

The crystal structures of four active site-directed thrombin inhibitors, 1-4, in a complex with human alpha-thrombin have been determined and refined at up to 2.0 A resolution using X-ray crystallography. These compounds belong to a structurally novel family of inhibitors based on a 2,3-disubstituted benzo[b]thiophene structure. Compared to traditional active-site directed inhibitors, the X-ray crystal structures of these complexes reveal a novel binding mode. Unexpectedly, the lipophilic benzo[b]thiophene nucleus of the inhibitor appears to bind in the S1 specificity pocket. At the same time, the basic amine of the C-3 side chain of the inhibitor interacts with the mostly hydrophobic proximal, S2, and distal, S3, binding sites. The second, basic amine side chain at C-2 was found to point away from the active site, occupying a location between the S1 and S1' sites. Together, the aromatic rings of the C-2 and C-3 side chains sandwich the indole ring of Trp60D contained in the thrombin S2 insertion loop defined by the sequence "Tyr-Pro-Pro-Trp." [The thrombin residue numbering used in this study is equivalent to that reported for chymotrypsinogen (Hartley BS, Shotton DM, 1971, The enzymes, vol. 3. New York: Academic Press. pp 323-373).] In contrast to the binding mode of more classical thrombin inhibitors (D-Phe-Pro-Arg-H, NAPAP, Argatroban), this novel class of benzo[b]thiophene derivatives does not engage in hydrogen bond formation with Gly216 of the thrombin active site. A detailed analysis of the three-dimensional structures not only provides a clearer understanding of the interaction of these agents with thrombin, but forms a foundation for rational structure-based drug design. The use of the data from this study has led to the design of derivatives that are up to 2,900-fold more potent than the screening hit 1.

1,2-Dibenzamidobenzene inhibitors of human factor Xa.

High-throughput screening of a combinatorial library of diamidophenols yielded lead compounds with the ability to inhibit human factor Xa (fXa) at micromolar concentrations (e.g. compound 4, fXa apparent K(ass) = 0.64 x 10(6) L/mol). SAR studies in this novel structural series of fXa inhibitors showed that the phenolic hydroxyl group was not essential for activity. The best activity was found in substituted 1,2-dibenzamidobenzenes in which the phenyl group of one benzoyl group (A-ring) was substituted in the 4-position with relatively small lipophilic or polarizable groups such as methoxy, vinyl, or chloro and the phenyl group of the other benzoyl group (B-ring) was substituted in the 4-position with larger lipophilic groups such as tert-butyl or dimethylamino. The central phenyl ring (C-ring) tolerated a wide variety of substituents, but methoxy, methanesulfonamido, hydroxyl, and carboxyl substitution produced slightly higher levels of activity than other substituents when present in combination with favorable B-ring substitution. Methylation of the amide nitrogen atoms was found to greatly decrease activity. Compound 12 is the highest affinity fXa inhibitor in this group of compounds, having fXa apparent K(ass) = 25.5 x 10(6) L/mol, about 40x more active than the original lead. This lead series does not show potent inhibition of human thrombin. A model for the binding of these ligands to the fXa active site is proposed. The model is consistent with the observed SAR and can serve to guide future SAR studies.

N(2)-Aroylanthranilamide inhibitors of human factor Xa.

Reversal of the A-ring amide link in 1,2-dibenzamidobenzene 1 (fXa K(ass) = 0.81 x 10(6) L/mol) led to a series of human factor Xa (hfXa) inhibitors based on N(2)-aroylanthranilamide 4. Expansion of the SAR around 4 showed that only small planar substituents could be accommodated in the A-ring for binding to the S1 site of hfXa. Bulky groups such as 4-isopropyl, 4-tert-butyl, and 4-dimethylamino were favored in the B-ring to interact with the S4 site of hfXa. The central (C) ring containing a 5-methanesulfonamido group yielded greater activity than carbamoyl groups. Combining the beneficial features from the B- and C-ring SAR, compound 55 represents the most potent hfXa inhibitor in the N(2)-aroylanthranilamide 4 series with hfXa K(ass) = 58 x 10(6) L/mol (K(i) = 11.5 nM).

Structure-based design of potent, amidine-derived inhibitors of factor Xa: evaluation of selectivity, anticoagulant activity, and antithrombotic activity.

To enhance the potency of 1,2-dibenzamidobenzene-derived inhibitors of factor Xa (fXa), an amidine substituent was incorporated on one of the benzoyl side chains to interact with Asp189 in the S1 specificity pocket. Lead molecule 1 was docked into the active site of fXa to facilitate inhibitor design. Subsequently, iterative SAR studies and molecular modeling led to a 1000-fold increase in fXa affinity and a refined model of the new inhibitors in the fXa active site. Strong support for the computational model was achieved through the acquisition of an X-ray crystal structure using thrombin as a surrogate protein. The amidines in this series show high levels of selectivity for the inhibition of fXa relative to other trypsin-like serine proteases. Furthermore, the fXa affinity of compounds in this series (K(ass) = 50-500 x 10(6) L/mol) translates effectively into both anticoagulant activity in vitro and antithrombotic activity in vivo.

Diamino benzo[b]thiophene derivatives as a novel class of active site directed thrombin inhibitors. 5. Potency, efficacy, and pharmacokinetic properties of modified C-3 side chain derivatives.

A systematic investigation of the structure-activity relationships of the C-3 side chain of the screening hit 1a led to the identification of the potent thrombin inhibitors 23c, 28c, and 31c. Their activities (1240, 903, and 1271 x 10(6) L/mol, respectively) represent 2200- and 2900-fold increases in potency over the starting lead 1a. This activity enhancement was accomplished with an increase of thrombin selectivity. The in vitro anticoagulant profiles of derivatives 28c and 31c were determined, and they compare favorably with the clinical agent H-R-1-[4aS, 8aS]perhydroisoquinolyl-prolyl-arginyl aldehyde (D-Piq-Pro-Arg-H; 32). The more potent members of this series have been studied in an arterial/venous shunt (AV shunt) model of thrombosis and were found to be efficacious in reducing clot formation. However, their efficacy is currently limited by their rapid and extensive distribution following administration.

The design of potent, selective, non-covalent, peptide thrombin inhibitors utilizing imidazole as a S1 binding element.

Modeling of neutral or mildly basic functional groups in the S1 site of thrombin led to the targeting of imidazole as a S1 binding element and correctly predicted the optimal chain length for connecting this group with the S2 and S3 binding elements. Derivatives of 4-(3-aminopropyl)-imidazole can be selective inhibitors of thrombin demonstrating potent anticoagulant activity.

Dibasic benzo[B]thiophene derivatives as a novel class of active site directed thrombin inhibitors: 4. SAR studies on the conformationally restricted C3-side chain of hydroxybenzo[B]thiophenes.

A novel series of benzo[b]thiophene diamine thrombin inhibitors with a conformationally restricted C3-side chain 3 was investigated. The constrained C3-side chain by a cyclohexyl ring contributed to not only an additive but also a synergistic effect on the thrombin inhibitory activity. The SAR studies resulted in the discovery of a potent thrombin inhibitor 27 that was over 750-fold more potent than the initial lead compound 1.

Dibasic benzo[b]thiophene derivatives as a novel class of active site directed thrombin inhibitors: 2. Sidechain optimization and demonstration of in vivo efficacy.

Potent, subnanomolar thrombin inhibitors 4, 5, and 6 are developed through side chain optimization of novel, benzo[b]thiophene-based small organic entities 2 and 3 and through SAR additivity studies of the new structural elements identified. X-ray crystallographic studies of 4b-thrombin complex revealed a hydrophobic and an electrostatic interaction of these new elements with thrombin at the S2 and S3 binding sites. In vitro and in vivo pharmacological studies showed that 4, 5, and 6 are potent anticoagulants in human plasma with demonstrated antithrombotic efficacy in a rat model of thrombosis.

Diamino benzo[b]thiophene derivatives as a novel class of active site directed thrombin inhibitors: 3. Enhancing activity by imposing conformational restriction in the C-4" side chain.

The preparation and biological evaluation of a series of benzo[b]thiophene diamine thrombin inhibitors possessing conformationally restricted C-4" linkers are reported. Compared to the parent compounds 1a/b, the unsaturated derivatives 3a/b exhibited a modest twofold increase in thrombin inhibitory activity, while the more lipophilic carbocyclic ring containing analogs 4a/b affected an eightfold enhancement in potency.

Applications of combinatorial chemistry to drug design and development.

This article is a subjective review of the literature from 1998 to April 1999 describing combinatorial chemistry as applied to drug discovery. The first two sections cover proteinase inhibition and small molecule lead discovery for other target classes. The final section describes those combinatorial chemistry-related technologies we think most likely to impact on drug discovery in the future.

Dibasic benzo[b]thiophene derivatives as a novel class of active site directed thrombin inhibitors. 2. Exploring interactions at the proximal (S2) binding site.

In an effort to increase the thrombin inhibitory activity of a novel series of inhibitors (i.e., 1a), substituents were incorporated at the C-3" position of the C-3 aryl ring (2). Consistent with the X-ray crystallography studies, small hydrophobic groups at the C-3" site (Br and Me) enhanced thrombin inhibitory activity by 8-fold. However, a few more hydrophilic substituents (NO2 and OMe) also enhanced the potency of the series. The biological results are discussed in terms of molecular modeling studies.