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Chohan ZH, Pervez H, Rauf A, Khan KM, Maharvi GM, Supuran CT. Antibacterial and Antifugal Mono- and Di-substituted Symmetrical and Unsymmetrical Triazine-derived Schiff-bases and their Transition Metal Complexes. J Enzyme Inhib Med Chem 2008; 19:161-8. [PMID: 15449731 DOI: 10.1080/14756360310001656745] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
A new series of antibacterial and antifungal triazine-derived mono- and di-substituted (symmetrical and unsymmetrical) Schiff-bases and their cobalt(II), copper(II), nickel(II) and zinc(II) metal complexes have been synthesized and characterized by their elemental analyses, molar conductances, magnetic moments and IR and electronic spectral measurements. IR spectra indicated the ligands to act as tridentate towards divalent metal ions via a trazine-N, the azomethine-N and, indole-NH and deprotonated-O of salicylaldehyde. The magnetic moments and electronic spectral data suggest octahedral geometry for the Co(II), Ni(II) and Zn(II)complexes and square-pyramid for Cu(II) complexes. NMR spectral data of the ligands and their diamagnetic zinc(II) complexes well-define their proposed structures/geometries. Elemental analyses data of the ligands and metal complexes agree with their proposed structures/geometries. The synthesized ligands, along with their metal complexes were screened for their antibacterial activity against Escherichia coli, Bacillus subtillis, Shigella flexneri, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi and for antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata. The results of these studies show the metal complexes to be more antibacterial/ antifungal against two or more species as compared to the uncomplexed Schiff-base ligands.
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Dar A, Khan KM, Ateeq HS, Khan S, Rahat S, Perveen S, Supuran CT. Inhibition of monoamine oxidase–A activity in rat brain by synthetic hydrazines: Structure-activity relationship (SAR). J Enzyme Inhib Med Chem 2008; 20:269-74. [PMID: 16119198 DOI: 10.1080/14756360400026212] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
A series of hydrazine derivatives was synthesized in order to evaluate their monoamine oxidase A (MAO-A) inhibitory effects. MAO-A inhibitory activity of 4-tosyl benzoic acid carbohydrazide was quite potent, similarly to that of the corresponding 4-benzyloxy-benzoic acid carbohydrazide and its N-cyanoethylated derivative. Structural variations of these compounds, such as the replacement of the 4-substitutent, of the aromatic ring on which the carbohydrazide moiety is grafted, as well as cyclization of the hydrazide moiety in five- or six-membered rings caused either significant decline or complete loss of MAO inhibitory properties. The most active compound (4-tosyl benzoic acid carbohydrazide) was also subjected to the forced swim test, an animal model of depression, eliciting a marked reduction in immobility time in rats, without affecting the locomotor activity, implying that it possesses anti-depressant properties due to inhibition of MAO type-A.
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Macdonald HM, Kontulainen SA, Petit MA, Beck TJ, Khan KM, McKay HA. Does a novel school-based physical activity model benefit femoral neck bone strength in pre- and early pubertal children? Osteoporos Int 2008; 19:1445-56. [PMID: 18357403 DOI: 10.1007/s00198-008-0589-z] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2007] [Accepted: 01/30/2008] [Indexed: 11/28/2022]
Abstract
UNLABELLED The effects of physical activity on bone strength acquisition during growth are not well understood. In our cluster randomized trial, we found that participation in a novel school-based physical activity program enhanced bone strength acquisition and bone mass accrual by 2-5% at the femoral neck in girls; however, these benefits depended on teacher compliance with intervention delivery. Our intervention also enhanced bone mass accrual by 2-4% at the lumbar spine and total body in boys. INTRODUCTION We investigated the effects of a novel school-based physical activity program on femoral neck (FN) bone strength and mass in children aged 9-11 yrs. METHODS We used hip structure analysis to compare 16-month changes in FN bone strength, geometry and bone mineral content (BMC) between 293 children who participated in Action Schools! BC (AS! BC) and 117 controls. We assessed proximal femur (PF), lumbar spine (LS) and total body (TB) BMC using DXA. We compared change in bone outcomes between groups using linear regression accounting for the random school effect and select covariates. RESULTS Change in FN strength (section modulus, Z), cross-sectional area (CSA), subperiosteal width and BMC was similar between control and intervention boys, but intervention boys had greater gains in BMC at the LS (+2.7%, p = 0.05) and TB (+1.7%, p = 0.03) than controls. For girls, change in FN-Z tended to be greater (+3.5%, p = 0.1) for intervention girls than controls. The difference in change increased to 5.4% (p = 0.05) in a per-protocol analysis that included girls whose teachers reported 80% compliance. CONCLUSION AS! BC benefits bone strength and mass in school-aged children; however, our findings highlight the importance of accounting for teacher compliance in classroom-based physical activity interventions.
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Khan KM, Ali M, Ajaz A, Perveen S, Choudhary MI, Atta-ur-Rahman. Synthesis of 5-Arylidene Barbiturates: A Novel Class of DPPH Radical Scavengers. LETT DRUG DES DISCOV 2008. [DOI: 10.2174/157018008784619889] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Azim MK, Ahmed W, Khan IA, Rao NA, Khan KM. Identification of acridinyl hydrazides as potent aspartic protease inhibitors. Bioorg Med Chem Lett 2008; 18:3011-5. [DOI: 10.1016/j.bmcl.2008.02.060] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2007] [Revised: 02/05/2008] [Accepted: 02/25/2008] [Indexed: 10/22/2022]
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Scott A, Lian Ø, Bahr R, Hart DA, Duronio V, Khan KM. Increased mast cell numbers in human patellar tendinosis: correlation with symptom duration and vascular hyperplasia. Br J Sports Med 2008; 42:753-7. [PMID: 18308880 DOI: 10.1136/bjsm.2007.040212] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES The cellular basis of painful tendon overuse pathology (tendinosis) is poorly understood. It has been suggested that because of the close anatomical associations between mast cells and vessels in connective tissues, mast cells may mediate the development of tendon hypervascularity or oedema. OBJECTIVES To examine the distribution of mast cells in men and women with patellar tendinopathy. DESIGN Case-control study. METHODS Tendinopathic tissue was collected at open debridement of the patellar tendon and a control tendon from patients undergoing intramedullary nailing of the tibia. The tendon was assessed immunohistochemically by evaluating the distribution of mast cells (AA1), and markers for T lymphocytes (CD3) and macrophages (CD68). The vessel-area fraction was quantified using computer-assisted digital image analysis. RESULTS The prevalence of mast cells per mm(2) (mean 3.3 (SD 3.0)) was greater in tendinosis tissue than in controls (1.1 (1.5); p = 0.036). In patients with tendinosis, mast cell density was moderately correlated with the vessel-area fraction (r(2) = 0.49) and with symptom duration (r(2) = 0.52). CONCLUSION Mast-cell prevalence in patellar tendinopathy was increased and was predominantly associated with vascular hyperplasia, particularly in patients with longstanding symptoms. Future research should investigate whether mast cells play direct or indirect modulatory roles in the development and progression of human tendinosis.
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Zareef M, Iqbal R, Mirza B, Khan KM, Manan A, Asim F, Khana SW. Synthesis and antimicrobial activity of some derivatives of acylhydrazine including novel benzenediazasulfonamides. ARKIVOC 2008. [DOI: 10.3998/ark.5550190.0009.216] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Khan KM, Drescher MJ, Hatfield JS, Ramakrishnan NA, Drescher DG. Immunohistochemical localization of adrenergic receptors in the rat organ of corti and spiral ganglion. J Neurosci Res 2008; 85:3000-12. [PMID: 17671986 DOI: 10.1002/jnr.21404] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Alpha(1)-, beta(1)-, and beta(2)-adrenergic receptors (ARs), which mediate responses to adrenergic input, have been immunohistochemically identified within the organ of Corti and spiral ganglion with polyclonal antibodies of established specificity. Alpha(1)-AR was immunolocalized to sites overlapping supranuclear regions of inner hair cells as well as to nerve fibers approaching the base of inner hair cells, most evident in the basal cochlear turn. A similar preponderance across cochlear turns for alpha(1)-AR in afferent cell bodies in the spiral ganglion pointed to type I afferent dendrites as a possible neural source of alpha(1)-AR beneath the inner hair cell. Foci of immunoreactivity for alpha(1)-AR, putatively neural, were found overlapping supranuclear and basal sites of outer hair cells for all turns. Beta(1)- and beta(2)-ARs were immunolocalized to sites overlapping apical and basal poles of the inner and outer hair cells, putatively neural in part, with immunoreactive nerve fibers observed passing through the habenula perforata. Beta(1)- and beta(2)-ARs were also detected in the cell bodies of Deiters' and Hensen's cells. Within the spiral ganglion, beta(1)- and beta(2)-ARs were immunolocalized to afferent cell bodies, with highest expression in the basal cochlear turn, constituting one possible neural source of receptors within the organ of Corti, specifically on type I afferent dendrites. Beta(1)- and beta(2)-ARs in Hensen's and Deiters' cells would couple to Galphas, known to be present specifically in the supporting cells. Overall, adrenergic modulation of neural/supporting cell function within the organ of Corti represents a newly considered mechanism for modifying afferent signaling.
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Mushtaq N, Saify ZS, Noor F, Takween S, Akhtar S, Arif M, Khan KM. Synthesis and pharmacological activities of 7-azaindole derivatives. PAKISTAN JOURNAL OF PHARMACEUTICAL SCIENCES 2008; 21:36-39. [PMID: 18166517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
As a part of our program to discover novel analogues of 7-azaindole (1H-Pyrrolo[2,3-b] pyridine) having useful biological activities, some derivatives have been synthesized and evaluated for their analgesic and hypotensive activity. Compounds evaluated by thermal stimuli (tail immersion method) at the dose of 50 mg/kg of body weight revealed significant analgesic activity. Pethidine was used as reference drug. Same compounds tested at the dose of 75 mg/kg of body weight showed toxicity. Compounds tested for their effect on blood pressure in normotensive rat produced slight fall in blood pressure.
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Hussain A, Siddiqui HL, Zia-Ur-Rehman M, Elsegood MRJ, M Khan K. 4-Hydroxy-4,6a,6b,9,9,12a,14b-heptamethylperhydropicen-3-one hemihydrate isolated from Adiantum incisum. Acta Crystallogr Sect E Struct Rep Online 2007; 64:o264. [PMID: 21200829 PMCID: PMC2915320 DOI: 10.1107/s1600536807064021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Accepted: 11/28/2007] [Indexed: 11/23/2022]
Abstract
The title compound, C29H48O2·0.5H2O, is a triterpenoid isolated from the stems and rhizomes of Adiantum incisum. The basic skeleton of the molecule contains five six-membered rings, all adopting chair conformations, bearing a total of seven methyl, one hydroxyl and a keto group. There are two molecules of the triterpene and one water molecule of crystallization in the asymmetric unit. The two unique triterpenoid molecules hydrogen-bond directly via an O—H⋯O=C interaction, and are also bridged by the water molecule. The water also bridges to another pair of hydrogen-bonded triterpenoid molecules.
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Scott A, Lian Ø, Roberts CR, Cook JL, Handley CJ, Bahr R, Samiric T, Ilic MZ, Parkinson J, Hart DA, Duronio V, Khan KM. Increased versican content is associated with tendinosis pathology in the patellar tendon of athletes with jumper's knee. Scand J Med Sci Sports 2007; 18:427-35. [PMID: 18067512 DOI: 10.1111/j.1600-0838.2007.00735.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Expansion of the extracellular matrix is a prominent but poorly characterized feature of tendinosis. The present study aimed to characterize the extent and distribution of the large aggregating proteoglycan versican in patients with patellar tendinosis. We obtained tendon from tendinopathy patients undergoing debridement of the patellar tendon and from controls undergoing intramedullary tibial nailing. Versican content was investigated by Western blotting and immunohistochemistry. Microvessel thickness and density were determined using computer-assisted image analysis. Markers for smooth muscle actin, endothelial cells (CD31) and proliferating cells (Ki67) were examined immunohistochemically. Western blot analysis and immunohistochemical staining revealed elevated versican content in the proximal patellar tendon of tendinosis patients (P=0.042). Versican content was enriched in regions of fibrocartilage metaplasia and fibroblast proliferation, as well as in the perivascular matrix of proliferating microvessels and within the media and intima of arterioles. Microvessel density was higher in tendinosis tissue compared with control tissue. Versican deposition is a prominent feature of patellar tendinosis. Because this molecule is not only a component of normal fibrocartilagenous matrices but also implicated in a variety of soft tissue pathologies, future studies should further detail both pathological and adaptive roles of versican in tendons.
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Casañola-Martín GM, Marrero-Ponce Y, Khan MTH, Ather A, Khan KM, Torrens F, Rotondo R. Dragon method for finding novel tyrosinase inhibitors: Biosilico identification and experimental in vitro assays. Eur J Med Chem 2007; 42:1370-81. [PMID: 17637486 DOI: 10.1016/j.ejmech.2007.01.026] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2006] [Revised: 01/18/2007] [Accepted: 01/19/2007] [Indexed: 10/23/2022]
Abstract
QSAR (quantitative structure-activity relationship) studies of tyrosinase inhibitors employing Dragon descriptors and linear discriminant analysis (LDA) are presented here. A data set of 653 compounds, 245 with tyrosinase inhibitory activity and 408 having other clinical uses were used. The active data set was processed by k-means cluster analysis in order to design training and prediction series. Seven LDA-based QSAR models were obtained. The discriminant functions applied showed a globally good classification of 99.79% for the best model Class=-96.067+1.988 x 10(2)X0Av +9 1.907 BIC3 + 6.853 CIC1 in the training set. External validation processes to assess the robustness and predictive power of the obtained model were carried out. This external prediction set had an accuracy of 99.44%. After that, the developed models were used in ligand-based virtual screening of tyrosinase inhibitors from the literature and never considered in either training or predicting series. In this case, all screened chemicals were correctly classified by the LDA-based QSAR models. As a final point, these fitted models were used in the screening of new bipiperidine series as new tyrosinase inhibitors. These methods are an adequate alternative to the process of selection/identification of new bioactive compounds. The biosilico assays and in vitro results of inhibitory activity on mushroom tyrosinase showed good correspondence. It is important to stand out that compound BP4 (IC(50)=1.72 microM) showed higher activity in the inhibition against the enzyme than reference compound kojic acid (IC(50)=16.67 microM) and l-mimosine (IC(50)=3.68 microM). These results support the role of biosilico algorithm for the identification of new tyrosinase inhibitor compounds.
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Peng T, Li LQ, Peng MH, Liu ZM, Liu TW, Guo Y, Xiao KY, Qin Z, Ye XP, Mo XS, Yan LN, Lee BL, Shen HM, Tamae K, Wang LW, Wang Q, Khan KM, Wang KB, Liang RX, Wei ZL, Kasai H, Ong CN, Santella RM. Evaluation of oxidative stress in a group of adolescents exposed to a high level of aflatoxin B1--a multi-center and multi-biomarker study. Carcinogenesis 2007; 28:2347-54. [PMID: 17724371 DOI: 10.1093/carcin/bgm193] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The association between aflatoxin B1 (AFB1) exposure and oxidative stress was extensively examined in 84 adolescents from an area at high risk for hepatocellular carcinoma in China. Plasma level of aflatoxin B1-albumin adducts (AAAs) was associated with AFB1 excretion in urine (r = 0.394, P < 0.001). Urinary AFB1 was also associated with both the urinary excretion of 8-hydroxydeoxyguanosine (8-OHdG) (r > or = 0.479, P < 0.001) and 8-OHdG and hOGG1 levels in peripheral leukocytes (r > or = 0.308, P < or = 0.005). Similarly, AAA was significantly associated with both the urinary excretion of 8-OHdG (r > or = 0.259, P < or = 0.018) and the 8-OHdG and hOGG1 levels in peripheral leukocytes (r > or = 0.313, P < or = 0.004). In addition, urinary 8-OHdG was correlated with both the level of DNA 8-OHdG (r > or = 0.24, P < or = 0.05) and the expression of hOGG1 in peripheral leukocytes (r > or = 0.429, P < 0.001). Protein carbonyl content (PCC) level was significantly associated with not only the level of DNA 8-OHdG (r > or = 0.366, P < 0.001) and the urinary 8-OHdG (r > or = 0.258, P < or = 0.018) but also the expression of hOGG1 in peripheral leukocytes (r = 0.485, P < 0.001). A significant but weak association was found between high-performance liquid chromatograph-electrochemical detection (HPLC-ECD) and enzyme-linked immunosorbent assay (ELISA) for urinary 8-OHdG (r = 0.334, P = 0.002) and between HPLC-ECD and flow cytometry assays for 8-OHdG in leucocytes (r = 0.395, P < 0.001). Significant associations were observed between AAA and PCC and liver function indices (alanine aminotransferase and aspartate aminotransferase). These findings suggest significant contribution from AFB1 exposure to oxidative stress and subsequent repair among adolescents that may impose substantial risk for hepatocarcinogenesis in adulthood in this region.
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Mazhar M, Ali S, Khan KM. Lower homologues (methyl, ethyl) of diorganotin derivatives of germyl (substituted) propanoic acids: spectroscopic elucidations and biological studies. Nat Prod Res 2007; 21:749-58. [PMID: 17616905 DOI: 10.1080/14786410601130299] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Some novel lower homologues of diorganotin derivatives of germyl substituted propanoic acids with general formula [Ar(3)GeCH(R(1))CH(R(2))COO](2)SnR(2)(3), where Ar = p-CH(3)C(6)H(4), C(6)H(5), R(1) = p-CH(3)C(6)H(4), p-CH(3)OC(6)H(4), o-CH(3)OC(6)H(4), C(6)H(5), R(2) = H, CH(3), R(3) = CH(3), C(2)H(5) have been prepared by the condensation reaction of dialkyltin oxide and triarylgermyl(substituted) propanoic acid in 1 : 2 M ratio, respectively, and were characterized by IR, multinuclear ((1)H, (13)C, (119)Sn) NMR, (119 m)Sn Mössbauer spectroscopy. The synthesized compounds were also screened for their toxicity and possible antibacterial, antifungal activities and found some encouraging results.
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Amtul Z, Follmer C, Mahboob S, Mazhar M, Khan KM, Siddiqui RA, Muhammad S, Kazmi SA, Choudhary MI. Germa-γ-lactones as novel inhibitors of bacterial urease activity. Biochem Biophys Res Commun 2007; 356:457-63. [PMID: 17367756 DOI: 10.1016/j.bbrc.2007.02.158] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2007] [Accepted: 02/28/2007] [Indexed: 10/23/2022]
Abstract
Organogermanium compounds have been used as pharmacological agents. However, very few reports are available on the synthesis and antibacterial activities of lactones containing organogermaniums. The purpose of the present investigation was to determine the effects of different lactone-substituted organogermaniums on bacterial growth and their urease activity. We report synthesis of 12 germa-gamma-lactones (GeL) and their antimicrobial activities against several bacterial pathogens. Antibacterial action of all GeL was highly selective against Gram-negative bacilli, particularly Proteus mirabilis, an important pathogen infecting the urinary tract. Furthermore, our data indicate that 8-quinoline derivatives were more potent against P. mirabilis than 2-methyl-8-quinoline. For example, the beta-(o-methylphenyl)-gamma,gamma-bis(8-quinolinoxy)germa-gamma-lactone and beta-(o-methoxyphenyl)-gamma,gamma-bis(8-quinolinoxy)germa-gamma-lactone were maximally active with MIC(90) of 61 and 94 microM, respectively. In vitro studies demonstrated a linear correlation between antibacterial activity and inhibition of P. mirabilis urease enzyme. Further kinetic analyses revealed that inhibition occurred in a noncompetitive and concentration-dependent manner with the minimum IC(50) of 31 microM for beta-(o-methoxyphenyl)-gamma,gamma-bis(8-quinolinoxy)germa-gamma-lactone. In conclusion, these findings suggest that GeL have potential to be developed as antimicrobial agents against P. mirabilis infection.
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Abstract
Endoscopy in children has developed along with pediatric gastroenterology over the last four decades. Introduction of endoscopic techniques in adults precedes application in children, and pediatric endoscopists do fewer procedures than their adult counterparts whether routine or as an emergency. Training for pediatric endoscopists therefore needs to be thorough. This article in particular highlights developments in pediatric gastroenterology of importance to emergency procedures.
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Al-Qawasmeh RA, Al-Telb TH, Khan KM, Voelter W. New entries for regio- and enantiopure syntheses of pyrrolidene systems fused to carbohydrate templates. ARKIVOC 2007. [DOI: 10.3998/ark.5550190.0008.727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Akhtar T, Hameed S, Al-Masoudi NA, Khan KM. Synthesis and anti-HIV activity of new chiral 1,2,4-triazoles and 1,3,4-thiadiazoles. HETEROATOM CHEMISTRY 2007. [DOI: 10.1002/hc.20282] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Ashe MC, Khan KM, Davis JC, Guy P, McKay HA. Hand dominance and bone response after a distal radial fracture: a peripheral QCT study. J Clin Densitom 2007; 10:93-101. [PMID: 17289531 DOI: 10.1016/j.jocd.2006.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Revised: 08/08/2006] [Accepted: 09/19/2006] [Indexed: 11/28/2022]
Abstract
There are no reports on bone geometry or volumetric bone density adaptations in those who have sustained a distal radial fracture. We used peripheral quantitative computed tomography (pQCT) and dual-energy X-ray absorptiometry (DXA) to quantify bone and muscle response to immobilization. We measured side-side differences in women aged > or =50 yr who had previously sustained a wrist fracture (4.0+/-3.5 mean yr since fracture). We used pQCT and DXA to measure bone in 31 women (mean age 72.4+/-9.7 yr) at the 4% and 30% sites of bilateral radii; measured grip strength and functional outcome. Initially, we compared the fractured side to intact side and did not control for hand dominance. We observed greater total area (ToA) at the distal (4%) radius on the fractured side without a significant increase in density. At the midshaft (30% site), we observed significantly less ToA and cortical bone on the fracture side. Grip strength was also significantly less on the fractured side (p<0.01). We assessed dominant side fractures and nondominant fractures separately. We observed a greater discrepancy between limbs with a nondominant side fracture, even after accounting for dominance. This cross-sectional study suggests that the bone response to a nondominant fracture may differ from a dominant fracture.
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Parveen R, Perveen S, Aleem A, Khan KM. 1H NMR, mass spectroscopic studies and color fastness properties of methyl-4,6-dihydroxy-2-oxo-1-phenyl-5-arylazopyridine-3-carboxylate, part III: new disperse dyes. Nat Prod Res 2007; 21:7-12. [PMID: 17365681 DOI: 10.1080/14786410600906632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
1H NMR and mass spectroscopic studies of new disperse dyes synthesized from methyl-4,6-dihydroxy-2-oxo-1-phenyl pyridine-3-carboxylate. Application of the dyes on polyester fabric and color fastness properties are also studied. The dyes are also found to possess DPPH free radical scavenging activity.
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Burdi DK, Samejo MQ, Bhanger MI, Khan KM. Fatty acid composition of Abies pindrow (West Himalayan fir). PAKISTAN JOURNAL OF PHARMACEUTICAL SCIENCES 2007; 20:15-9. [PMID: 17337422] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The leaves of Abies pindrow, collected from Murree Hills, Punjab (Pakistan) revealed the presence of eleven fatty acids including eight saturated and three unsaturated fatty acids. They ranged from C(14) to C(24) and were detected as methyl esters by GC-MS technique. The saturated fatty acids were present in much greater proportion than unsaturated ones. Isopalmatic acid was found to be major saturated fatty acid and the oleic acid as predominant unsaturated acid. (+)-14-Methyl palmatic acid and (+)-Isosteric acid were the next higher saturated and unsaturated fatty acids respectively.
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Khan KM, Foker JE. Use of high-resolution endoscopic ultrasonography to examine the effect of tension on the esophagus during primary repair of long-gap esophageal atresia. Pediatr Radiol 2007; 37:41-5. [PMID: 17043852 DOI: 10.1007/s00247-006-0333-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2006] [Revised: 08/24/2006] [Accepted: 09/07/2006] [Indexed: 11/28/2022]
Abstract
BACKGROUND We have shown that tension applied to the esophageal pouches in long-gap esophageal atresia allows primary repair without necessity for intestinal or gastric transposition. OBJECTIVE To determine whether the mural structure of the upper esophageal pouch is altered by tension. MATERIALS AND METHODS We examined the esophagus with high-resolution endoscopic ultrasonography. The upper pouch was examined before traction and the upper and lower esophagus were examined after primary repair. Of 11 patients examined, 7 were male. At initial surgery the age, weight and length of the patients (mean +/- SD) were 118 +/- 88 days, 4.7 +/- 1.2 kg and 54 +/- 4 cm, respectively. The gap length was 4.7 +/- 1.1 cm. RESULTS The pretraction measurement of the muscularis propria of the upper pouch was similar to the postanastomotic measurement of the upper esophagus, and there was no statistically significant difference from the lower esophageal segments after anastomosis: 0.83 +/- 0.19, 0.80 +/- 0.15 and 0.81 +/- 0.22 mm, respectively (P = 0.90). The thickness of combined mucosa and submucosa was also very similar in all three measurements, respectively: 0.93 (0.21) mm vs. 1.06 (0.08) mm vs. 1.0 (0.11) mm (P = 0.14). CONCLUSION The layers of the upper esophageal pouch are preserved in infants with esophageal atresia in whom esophageal length is increased with tension.
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Khan KM, Sabati AA, Kendall T, Foker JE. The effect of traction on esophageal structure in children with long-gap esophageal atresia. Dig Dis Sci 2006; 51:1917-21. [PMID: 16977508 DOI: 10.1007/s10620-006-9169-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2005] [Accepted: 11/28/2005] [Indexed: 12/23/2022]
Abstract
We examined the esophageal structure in children who underwent traction to achieve primary repair of long-gap esophageal atresia. High-resolution ultrasound was used to compare thickness of the proximal and distal esophagus in children who had traction to achieve primary repair (n=15) to cases of esophageal atresia with shorter gaps that did not require traction (n=8). The muscularis propria of the upper esophagus was thicker in the traction compared to the non-traction group, though not statistically significant (respectively, 0.79 (0.18) mm vs. 0.71 (0.16) mm; p=0.29), measurements were similar for the lower esophagus (respectively, 0.79 (0.21) mm vs. 0.75 (0.13) mm; p=0.64). Combined mucosa and submucosa was very similar in both groups for the upper (respectively, 1.03 (0.15) mm vs. 1.04 (0.16) mm; p=0.95) and lower esophagus (respectively, 1.09 (0.23) mm vs. 1.01 (0.13) mm; p=0.37). The thickness of individual mural layers is maintained after increasing esophageal length with traction.
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Amtul Z, Kausar N, Follmer C, Rozmahel RF, Kazmi SA, Shekhani MS, Eriksen JL, Khan KM, Choudhary MI. Cysteine based novel noncompetitive inhibitors of urease(s)—Distinctive inhibition susceptibility of microbial and plant ureases. Bioorg Med Chem 2006; 14:6737-44. [PMID: 16859909 DOI: 10.1016/j.bmc.2006.05.078] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2006] [Revised: 05/26/2006] [Accepted: 05/26/2006] [Indexed: 11/19/2022]
Abstract
Based on the catalysis mechanism of urease, a homologous series of 10 cysteine derivatives (CysDs) was designed and synthesized, and their inhibitory activities were evaluated for microbial ureases (Bacillus pasteurii, BPU, and Proteus mirabilis, PMU) and for a plant urease [jack bean (Cavavalia ensiformis), JBU]. As already described, thiol-compounds might inhibit urease activity by chelating the nickel atoms involved in the catalysis process. In contrast to cysteine, which has been reported to be a very weak urease inhibitor, we verified a potential inhibitory activity of these CysDs. The kinetic data demonstrate that thiol derivatives are more effective than the respective thioether derivatives. Besides, thiol-CysDs had a reduced activity in acidic pH (5.0). Lineweaver-Burk plots indicated that the nature of inhibition was of noncompetitive type for all 10 compounds, with the minimum Ki value of 2 microM for N,N-dimethyl L-cysteine. It is proposed that these classes of compounds are more potent inhibitors of the bacterial ureases, compared with the plant-originated urease. Since microbial urease is directly involved in the infection process of many pathological organisms, this work demonstrates that thiol-CysDs represent a class of new potential urease inhibitors.
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Liu-Ambrose T, Kravetsky L, Bailey D, Sherar L, Mundt C, Baxter-Jones A, Khan KM, McKay HA. Change in lean body mass is a major determinant of change in areal bone mineral density of the proximal femur: a 12-year observational study. Calcif Tissue Int 2006; 79:145-51. [PMID: 16969588 DOI: 10.1007/s00223-006-0098-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2006] [Accepted: 06/21/2006] [Indexed: 11/25/2022]
Abstract
Our objective was to assess the contribution of lean body mass (LBM) and fat body mass (FBM) to areal bone mineral density (aBMD) in women during the years surrounding menopause. We used a 12-year observational design. Participants included 75 Caucasian women who were premenopausal, 53 of whom were available for follow-up. There were two measurement periods: baseline and 12-year follow-up. At both measurement periods, bone mineral content and aBMD of the proximal femur, posterior-anterior lumbar spine, and total body was assessed using dual-energy X-ray absorptiometry (DXA). LBM and FBM were derived from the total-body scans. General health, including current menopausal status, hormone replace therapy use, medication use, and physical activity, was assessed by questionnaires. At the end of the study, 44% of the women were postmenopausal. After controlling for baseline aBMD, current menopausal status, and current hormone replacement therapy, we found that change in LBM was independently associated with change in aBMD of the proximal femur (P = 0.001). The cross-sectional analyses also indicated that LBM was a significant determinant of aBMD of all three DXA-scanned sites at both baseline and follow-up. These novel longitudinal data highlight the important contribution of LBM to the maintenance of proximal femur bone mass at a key time in women's life span, the years surrounding menopause.
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Hussain MT, Rama NH, Hameed S, Malik A, Khan KM. Chemistry of isocoumarins: synthesis and biological screenings of Homalicine and dihydrohomalicine. Nat Prod Res 2006; 19:41-51. [PMID: 15700644 DOI: 10.1080/14786410310001643821] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Total synthesis and selected biological activities of naturally occurring homalicine and (dl)-dihydrohomalicine are described.
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Choudhary MI, Fatima N, Khan KM, Jalil S, Iqbal S. New biscoumarin derivatives-cytotoxicity and enzyme inhibitory activities. Bioorg Med Chem 2006; 14:8066-72. [PMID: 16919464 DOI: 10.1016/j.bmc.2006.07.037] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2006] [Revised: 07/19/2006] [Accepted: 07/20/2006] [Indexed: 11/20/2022]
Abstract
Biscoumarin derivatives 1-27 were tested for their inhibition of snake venom and human nucleotide pyrophosphatase phosphodiesterase-1 enzymes. Lineweaver-Burk and Dixon plots and their secondary replots showed that these compounds are pure non-competitive inhibitors of both the enzymes. Ki and IC50 values of biscoumarins were found to be in the range of 50 to 1000 and 164 to > 1000 microM, respectively, against human recombinant phosphodiesterase 1 enzyme and 8.0 to 1150 and 9.44 to > 1000 microM, respectively, against snake venom phosphodiesterase. Compounds 1, 3, 4, 6, 7, 17, 26, and 30 were found to be non-competitive and non-cytotoxic upto a concentration of 200 microg/mL as evident by less than 10% cell death after 3 h of incubation.
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Khan KM, Sarfaraz N, Siddiqui S, Nawaz H. Immunohistochemical localization of G protein betagamma subunits in the lateral wall of the rat cochlea. J Anat 2006; 208:205-18. [PMID: 16441565 PMCID: PMC2100195 DOI: 10.1111/j.1469-7580.2006.00526.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
The role of G protein-mediated signal transduction in the production of endolymph, an extracellular fluid of unusual ionic composition, is beginning to be understood. The identity of Galpha subunits in the stria vascularis and the spiral ligament of the lateral wall of the cochlear duct is well established. However, little is known about the presence of betagamma subunits. This study used immunohistochemistry to investigate the distribution of G protein betagamma subunits in the lateral wall of the cochlea. Temporal bones of 6- to 8-week-old rats were fixed in 4% paraformaldehyde and 0.1% glutaraldehyde and processed for embedding in paraffin wax. The dewaxed, midmodiolar sections of the cochlea were incubated with subunit-specific polyclonal antibodies. The results show that the pattern of immunoreactivity varies for the G protein beta1-4 and gamma1-3, 5 and 7 subunits in the stria vascularis and spiral ligament. In the stria vascularis, immunoreactivity was detected for beta2, beta3, beta4, gamma1, gamma2 and gamma7 subunits. All five types of fibrocytes in the spiral ligament exhibited positive staining for gamma2 and gamma7. However, immunoreactivity for beta1-4 subunits was variable. Immunoreactivity for gamma3 and gamma5 subunits was not detected in the lateral cochlear wall. The expression pattern of G protein betagamma subunits in lateral wall provides a basis for interpreting the functions of G protein-coupled receptors in cochlear fluid homeostasis.
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Drescher MJ, Drescher DG, Khan KM, Hatfield JS, Ramakrishnan NA, Abu-Hamdan MD, Lemonnier LA. Pituitary adenylyl cyclase-activating polypeptide (PACAP) and its receptor (PAC1-R) are positioned to modulate afferent signaling in the cochlea. Neuroscience 2006; 142:139-64. [PMID: 16876955 DOI: 10.1016/j.neuroscience.2006.05.065] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2006] [Revised: 05/02/2006] [Accepted: 05/09/2006] [Indexed: 10/24/2022]
Abstract
Pituitary adenylyl cyclase-activating polypeptide (PACAP), via its specific receptor pituitary adenylyl cyclase-activating polypeptide receptor 1 (PAC1-R), is known to have roles in neuromodulation and neuroprotection associated with glutamatergic and cholinergic neurotransmission, which, respectively, are believed to form the primary basis for afferent and efferent signaling in the organ of Corti. Previously, we identified transcripts for PACAP preprotein and multiple splice variants of its receptor, PAC1-R, in microdissected cochlear subfractions. In the present work, neural localizations of PACAP and PAC1-R within the organ of Corti and spiral ganglion were examined, defining sites of PACAP action. Immunolocalization of PACAP and PAC1-R in the organ of Corti and spiral ganglion was compared with immunolocalization of choline acetyltransferase (ChAT) and synaptophysin as efferent neuronal markers, and glutamate receptor 2/3 (GluR2/3) and neurofilament 200 as afferent neuronal markers, for each of the three cochlear turns. Brightfield microscopy giving morphological detail for individual immunolocalizations was followed by immunofluorescence detection of co-localizations. PACAP was found to be co-localized with ChAT in nerve fibers of the intraganglionic spiral bundle and beneath the inner and outer hair cells within the organ of Corti. Further, evidence was obtained that PACAP is expressed in type I afferent axons leaving the spiral ganglion en route to the auditory nerve, potentially serving as a neuromodulator in axonal terminals. In contrast to the efferent localization of PACAP within the organ of Corti, PAC1-R immunoreactivity was co-localized with afferent dendritic neuronal marker GluR2/3 in nerve fibers passing beneath and lateral to the inner hair cell and in fibers at supranuclear and basal sites on outer hair cells. Given the known association of PACAP with catecholaminergic neurotransmission in sympathoadrenal function, we also re-examined the issue of whether the organ of Corti receives adrenergic innervation. We now demonstrate the existence of nerve fibers within the organ of Corti which are immunoreactive for the adrenergic marker dopamine beta-hydroxylase (DBH). DBH immunoreactivity was particularly prominent in nerve fibers both at the base and near the cuticular plate of outer hair cells of the apical turn, extending to the non-sensory Hensen's cell region. Evidence was obtained for limited co-localization of DBH with PAC1-R and PACAP. In the process of this investigation, we obtained evidence that efferent and afferent nerve fibers, in addition to adrenergic nerve fibers, are present at supranuclear sites on outer hair cells and distributed within the non-sensory epithelium of the apical cochlear turn for rat, based upon immunoreactivity for the corresponding neuronal markers. Overall, PACAP is hypothesized to act within the organ of Corti as an efferent neuromodulator of afferent signaling via PAC1-R that is present on type I afferent dendrites, in position to afford protection from excitotoxicity. Additionally, PACAP/PAC1-R may modulate secretion of catecholamines from adrenergic terminals within the organ of Corti.
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Ashe MC, Fehling P, Eng JJ, Khan KM, McKay HA. Bone geometric response to chronic disuse following stroke: a pQCT study. JOURNAL OF MUSCULOSKELETAL & NEURONAL INTERACTIONS 2006; 6:226-33. [PMID: 17142942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
OBJECTIVES The objectives of this study were to 1) assess volumetric bone geometry and density at the distal radius of individuals with chronic stroke and 2) assess whether bone strength is associated with measures of muscle strength and impairment. MATERIAL AND METHODS Cross-sectional study of bone and muscle parameters in 15 community-dwelling people living with the residual effects of a stroke (between 1 and 9 years post-incident stroke). RESULTS The 4% site of the distal radius had significantly lower bone mineral content and density on the paretic side (p<0.006). There was a significant difference in pQCT measures of bone cortical density (p<0.03), area (p<0.05) and bone strength [Stress-Strain Index; SSI] (p<0.01) (lower on the paretic side) at the 30%. We found significant correlations between composite muscle strength score of the upper extremities and pQCT-generated bone strength. CONCLUSIONS This cross-sectional study highlights lower bone strength on the paretic limb and an adaptive response to disuse.
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Ramakrishnan NA, Drescher MJ, Sheikhali SA, Khan KM, Hatfield JS, Dickson MJ, Drescher DG. Molecular identification of an N-type Ca2+ channel in saccular hair cells. Neuroscience 2006; 139:1417-34. [PMID: 16581196 DOI: 10.1016/j.neuroscience.2006.01.064] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2005] [Revised: 01/26/2006] [Accepted: 01/26/2006] [Indexed: 11/17/2022]
Abstract
We report new molecular evidence for the presence of an N-type (Ca(v)2.2, alpha1B) voltage-gated Ca(2+) channel in hair cells of the saccular epithelium of the rainbow trout. The Ca(v)2.2 amino-acid sequence shows 68% and 63% identity compared with chick and human Ca(v)2.2, respectively. This channel reveals features that are characteristic of an N-type Ca(2+) channel: an omega-conotoxin GVIA binding domain, G(betagamma) binding regions, and a synaptic protein interaction site. Immunohistochemical studies with a custom antibody show that immunoreactivity for the Ca(v)2.2 is concentrated in the basolateral and apical regions of hair cells. Whereas trout brain and saccular macula express an 11-amino-acid insert in the second G(betagamma) binding domain of the Ca(v)2.2 I-II loop, isolated hair cells appear not to express this variant. We constructed fusion polypeptides representing portions of the I-II loop, beta1 and beta2a auxiliary subunits, the II-III loop, and syntaxin, and examined their intermolecular interactions via immunoprecipitation and surface plasmon resonance. The I-II loop polypeptides bound both beta1 and beta2a subunits with a preference for beta1, and the II-III loop exhibited Ca(2+)-dependent syntaxin binding. We demonstrated syntaxin immunoreactivity near afferent endings in hair cells, at hair-cell apices, and in efferent endings on hair cells, the former two sites consistent with binding of syntaxin to Ca(v)2.2. The present molecular characterization of the Ca(v)2.2 channel provides novel biochemical evidence for an N-type channel in hair cells, and details molecular interactions of this channel that reflect hair-cell function, such as spontaneous activity and vesicular trafficking. The current work, to our knowledge, represents the first demonstration of a putative N-type channel in hair cells as documented by tissue-specific antibody immunoreactivity and hair-cell-specific cDNA sequence.
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Imtiaz-ud-Din, Mazhar M, Molloy K, Khan KM. Synthesis, structural characterization of some germanium substituted chiral diethyltin derivatives. J Organomet Chem 2006. [DOI: 10.1016/j.jorganchem.2005.12.013] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Stanley AG, Khan KM, Hussain W, Tweed M. Disorganized junior doctors fail the MRCP (UK). MEDICAL TEACHER 2006; 28:e40-2. [PMID: 16627323 DOI: 10.1080/01421590600568421] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Career progression during undergraduate and early postgraduate years is currently determined by successfully passing examinations. Both academic factors (secondary school examination results, learning style and training opportunities) and non-academic factors (maturity, ethnic origin, gender and motivation) have been identified as predicting examination outcome. Few studies have examined organization skills. Disorganized medical students are more likely to perform poorly in end-of-year examinations but this observation has not been examined in junior doctors. This study asked whether organization skills relate to examination outcome amongst junior doctors taking the clinical Part II examination for the Membership of the Royal College of Physicians (Practical Assessment of Clinical Examination Skills). The study was conducted prospectively at four consecutive clinical courses that provided clinical teaching and practice to prepare trainees for the examination. Arrival time at registration for the course was the chosen surrogate for organization skills. Trainees were advised that they should arrive promptly at 8.00 a.m. for registration and it was explained that the course would start at 8.30 a.m. Recorded arrival times were compared with the pass lists published by the Royal College of Physicians. The mean arrival time was 8.17 a.m. A total of 81 doctors (53.3%) passed the examination with a mean arrival time of 8.14 a.m. However, 71 doctors failed the exam and arrived, on average, six minutes later than doctors who passed (p?=?0.006). Better-prepared junior doctors were more likely to pass the final examination. Arriving on time represents a composite of several skills involved in the planning of appropriate travel arrangements and is therefore a valid marker of organization skills and preparation. This novel study has shown that good time-keeping skills are positively associated with examination outcome.
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Matthews BL, Bennell KL, McKay HA, Khan KM, Baxter-Jones ADG, Mirwald RL, Wark JD. Dancing for bone health: a 3-year longitudinal study of bone mineral accrual across puberty in female non-elite dancers and controls. Osteoporos Int 2006; 17:1043-54. [PMID: 16758141 DOI: 10.1007/s00198-006-0093-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2005] [Accepted: 02/10/2006] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Weight-bearing exercise during growth enhances peak bone mass. However, the window of opportunity for optimizing positive effects of exercise on peak bone mass remains to be fully defined. Ballet dancing provides a model of mechanical loading patterns required to site-specifically modulate bone. METHODS We assessed the effects of ballet dancing on bone mineral accrual in female non-elite dancers and normally active controls for 3 years across puberty. We recruited 82 ballet dancers and 61 controls age 8-11 years at baseline. Participants were measured over 3 consecutive years; however, the overlap in ages allowed analysis of the groups across 8-14 years of age. We annually assessed bone mineral content (BMC) at the total body (TB), including upper and lower limb regions, and biannually assessed BMC at the proximal femur and lumbar spine (LS) using dual x-ray absorptiometry (DXA). We derived TB lean mass and fat mass from DXA TB scans. Anthropometry, exercise levels, and calcium intake were also measured biannually. Maturational age was determined by age at peak height velocity (PHV). A multilevel regression model was used to determine the independent effects of body size, body composition, maturation, exercise levels, and calcium intake at each measurement occasion. RESULTS When adjusted for growth and maturation, dancers had significantly greater BMC at the TB, lower limbs, femoral neck (FN), and LS than controls. Excepting the FN region, these differences became apparent at 1 year post-PHV, or the peripubertal years, and by 2 years post-PHV the differences represented a cumulative advantage in dancers of 0.6-1.3% (p<0.05) greater BMC than controls. At the FN, dancers had 4% (p<0.05) greater BMC than controls in prepuberty and maintained this advantage throughout the pubertal years. CONCLUSIONS Results from this novel population provide evidence for modest site-specific and maturity-specific effects of mechanical loading on bone.
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Ashe MC, Khan KM, Kontulainen SA, Guy P, Liu D, Beck TJ, McKay HA. Accuracy of pQCT for evaluating the aged human radius: an ashing, histomorphometry and failure load investigation. Osteoporos Int 2006; 17:1241-51. [PMID: 16683179 DOI: 10.1007/s00198-006-0110-5] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2005] [Accepted: 03/03/2006] [Indexed: 11/27/2022]
Abstract
INTRODUCTION Quantifying the determinants of bone strength is essential to understanding if or how the structure will fail under load. Determining failure requires knowledge of material and geometric properties. However, characterizing the relative contributions of geometric parameters of bone to overall bone strength has been difficult to date because of limitations in imaging technology. Peripheral quantitative computed tomography (pQCT) uses digital images to derive estimates of bone strength in the peripheral skeleton and is a relatively safe technique to differentiate cortical from trabecular bone and assess bone geometry and density. However, in a compromised osteoporotic bone, thin cortices and low scan resolution can limit accurate analysis. METHODS Therefore, in this two-part investigation we scanned ten pairs (n=20) of fresh-frozen radial specimens [female, mean (SD) age 79(6) years] using pQCT (XCT 2000) at the 4 and 30% sites of the distal radius. We investigated the accuracy of four different acquisition resolutions (200, 300, 400, 500 microm) and several analysis modes and thresholds. We evaluated (1) the accuracy of the Norland/Stratec XCT 2000 pQCT in assessing low-density bones by comparing pQCT outcomes to ashing and histomorphometry and (2) the association of geometric parameters by pQCT and areal bone mineral density (aBMD) by dual-energy X-ray absorptiometry (DXA) to failure load at the distal radius. RESULTS Using histomorphometry and ashing as reference standards, we found that pQCT scans varied systematically and underestimated or overestimated total area and mineral content at the radial midshaft depending on the analysis algorithm and selected threshold. Overall, most pQCT analysis modes were accurate. In the mechanical testing studies, bone mineral content and cortical bone content at the midshaft were strongly associated with failure load. The pQCT parameters that best accounted for failure load were total content at the 4% site and cortical thickness at the 30% site and they accounted for up to 81% of the variance. The best DXA predictor of failure load was total density at the distal third site and it explained 75% of the variance. CONCLUSIONS In summary, analysis mode, resolution and thresholding affected pQCT outputs at the radial midshaft. This study extends our understanding of pQCT analysis and provides important data regarding determinants of bone strength at the distal radius.
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Salter AE, Khan KM, Donaldson MG, Davis JC, Buchanan J, Abu-Laban RB, Cook WL, Lord SR, McKay HA. Community-dwelling seniors who present to the emergency department with a fall do not receive Guideline care and their fall risk profile worsens significantly: a 6-month prospective study. Osteoporos Int 2006; 17:672-83. [PMID: 16491323 DOI: 10.1007/s00198-005-0032-7] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2005] [Accepted: 10/18/2005] [Indexed: 11/25/2022]
Abstract
INTRODUCTION Fall risk is a major contributor to fracture risk; implementing fall reduction programmes remains a challenge for health professionals and policy-makers. MATERIALS AND METHODS We aimed to (1) ascertain whether the care received by 54 older adults after an emergency department (ED) fall presentation met internationally recommended 'Guideline Care', and (2) prospectively evaluate this cohort's 6-month change in fall risk profile. Participants were men and women aged 70 years or older who were discharged back into the community after presenting to an urban university tertiary-care hospital emergency department with a fall-related complaint. American Geriatric Society (AGS) guideline care was documented by post-presentation emergency department chart examination, daily patient diary of falls submitted monthly, patient interview and physician reconciliation where needed. Both at study entry and at a 6-month followup, we measured participants physiological characteristics by Lord's Physiological Profile Assessment (PPA), functional status, balance confidence, depression, physical activity and other factors. RESULTS We found that only 2 of 54 (3.7%) of the fallers who presented to the ED received care consistent with AGS Guidelines. Baseline physiological fall risk scores classified the study population at a 1.7 SD higher risk than a 65-year-old comparison group, and during the 6-month followup period the mean fall-risk score increased significantly (i.e. greater risk of falls) (1.7+/-1.6 versus 2.2+/-1.6, p=0.000; 29.5% greater risk of falls). Also, functional ability [100 (15) versus 95 (25), p=0.002], balance confidence [82.5 (44.4) versus 71.3 (58.7), p=0.000] and depression [0 (2) versus 0 (3), p=0.000] all worsened over 6 months. Within 6 months of the index ED visit, five participants had suffered six fall-related fractures. DISCUSSION We conclude that this group of community-dwelling fallers, who presented for ED care with a clinical profile suggesting a high risk of further falls and fracture, did not receive Guideline care and worsened in their fall risk profile by 29.5%. This gap in care, at least in one centre, suggests further investigation into alternative approaches to delivering Guideline standard health service.
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Abu-Hamdan MD, Drescher MJ, Ramakrishnan NA, Khan KM, Toma VS, Hatfield JS, Drescher DG. Pituitary Adenylyl Cyclase-Activating Polypeptide (PACAP) and its receptor (PAC1-R) in the cochlea: Evidence for specific transcript expression of PAC1-R splice variants in rat microdissected cochlear subfractions. Neuroscience 2006; 140:147-61. [PMID: 16626868 DOI: 10.1016/j.neuroscience.2006.01.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2005] [Revised: 12/28/2005] [Accepted: 01/06/2006] [Indexed: 11/26/2022]
Abstract
Pituitary adenylyl cyclase-activating polypeptide (PACAP) is a neuropeptide originally isolated from the hypothalamus, named for its high potency in stimulating adenylyl cyclase in pituitary cells. PACAP acts through the specific receptor PAC1-R to modulate the action of neurotransmitters, and additionally, to regulate cell viability via autocrine/intracrine mechanisms. Evidence has now been obtained that PACAP and multiple splice variants of PAC1-R are expressed in the rat cochlea. mRNA for PACAP precursor protein is found by reverse transcription-polymerase chain reaction (RT-PCR) in microdissected cochlear lateral wall, organ of Corti, and spiral ganglion subfractions. A specific pattern of expression of mRNA for PAC1-R splice variants, which mediate the response to PACAP, has been revealed by RT-PCR and cloning for the cochlear subfractions. Transcript for the short form of PAC1-R is found in all three subfractions. Four additional splice variants -- hop1, hop2, hip, and a novel hop1 splice variant -- are expressed in the lateral wall. For the amino terminus splice region of PAC1-R, a new splice variant has been detected in the organ of Corti, representing a deletion of the first 7 of 21 amino acids detected in the PAC1-R very-short sequence. Overall, from message determinations in cochlear subfractions, there are five PAC1-R splice variants in the lateral wall, two in the organ of Corti and one in the spiral ganglion, indicating multiple possible responses to PACAP and/or mechanisms to modulate the response to PACAP in the cochlea. The variety of PAC1-R splice variants expressed may reflect the diversity in cell function between subfractions that is modulated by PACAP. The neuropeptide and its specific receptor have been immunolocalized in the lateral wall, the source of the largest number of cochlear PAC1-R splice variants. The receptor was targeted by primary antibodies which would elicit immunoreactivity for all splice variants of PAC1-R detected with RT-PCR, and evidence has been obtained with Western blot analysis suggesting that PAC1-R is glycosylated in vivo. Within the lateral wall, PACAP and PAC1-R were immunolocalized primarily to the stria vascularis, with immunoreactivity for both neuropeptide and receptor increasing from the basal to apical cochlear turns. Within the stria, PACAP immunoreactivity was localized to the basolateral extensions of marginal cells, while PAC1-R was clearly associated with tight junctions between the marginal cells close to the endolymphatic compartment. In addition, evidence was obtained that PAC1-R was associated with endothelial cells of the capillaries in the stria vascularis. The large number of splice variants expressed, coupled to the specificity in linkage between PAC1-R splice variants and G-protein-coupled second messenger pathways, could provide a mechanism to closely modulate tight junction integrity in the stria vascularis, impacting the endolymphatic potential.
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McKay HA, MacLean L, Petit M, MacKelvie-O'Brien K, Janssen P, Beck T, Khan KM. "Bounce at the Bell": a novel program of short bouts of exercise improves proximal femur bone mass in early pubertal children. Br J Sports Med 2005; 39:521-6. [PMID: 16046335 PMCID: PMC1725273 DOI: 10.1136/bjsm.2004.014266] [Citation(s) in RCA: 135] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To examine the effects of a simple and inexpensive physical activity intervention on change in bone mass and structure in school aged children. METHODS Fifty one children (n = 23 boys and 28 girls; mean age 10.1 years) participated in "Bounce at the Bell" which consisted of 10 counter-movement jumps 3x per day (total approximately 3 min/day). Controls were 71 matched children who followed usual school practice. We assessed dietary calcium, physical activity, physical performance, and anthropometry in September and after 8 months of intervention (June). We measured bone mineral content (BMC) and bone area at the lumbar spine, total body, and proximal femur. Proximal femur scans were also analysed for bone geometry and structural strength using the hip structural analysis program. Lean and fat mass (g) were also calculated. RESULTS Groups were similar at baseline and did not differ in weight, height, total body, lumbar spine, proximal femur, or femoral neck BMC. Control children had a greater increase in adjusted total body BMC (1.4%). Intervention children gained significantly more BMC at the total proximal femur (2%) and the intertrochanteric region (27%). Change in bone structural parameters did not differ between groups. CONCLUSIONS This novel, easily implemented exercise program, took only a few minutes each day and enhanced bone mass at the weight bearing proximal femur in early pubertal children. A large, randomised study of boys and girls should be undertaken powered to test the effectiveness of Bounce at the Bell in children at different stages of maturity, and in boys and girls independently.
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Shah STA, Khan KM, Hussain H, Hayat S, Voelter W. CsF-Celite, an Efficient Solid State Reagent for the Syntheses of Thioesters and Thioethers. MONATSHEFTE FUR CHEMIE 2005. [DOI: 10.1007/s00706-005-0351-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Chohan ZH, Pervez H, Khan KM, Supuran CT. Organometallic-based antibacterial and antifungal compounds: transition metal complexes of 1,1'-diacetylferrocene-derived thiocarbohydrazone, carbohydrazone, thiosemicarbazone and semicarbazone. J Enzyme Inhib Med Chem 2005; 20:81-8. [PMID: 15895689 DOI: 10.1080/14756360410001733748] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Organometallic-based, 1,1'-diacetylferrocene-derived antibacterial and antifungal thiocarbohydrazone, carbohydrazone, thiosemicarbazone and semicarbazone have been prepared by condensing equimolar amount of 1,1'-diacetylferrocene with thiocarbohydrazide, carbohydrazide thiosemicarbazide and semicarbazide, respectively. These were used as ligands for the preparation of their cobalt (II), copper (II), nickel (II) and zinc (II) metal complexes. All the synthesized ligands and their complexes were characterized by IR, NMR, elemental analyses, molar conductances, magnetic moments and electronic spectral data. These synthesized compounds were screened for their antibacterial activity against Escherichia coli, Bacillus subtillis, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi, and for antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata using the agar-well diffusion method. All the compounds showed good antibacterial and antifungal activity which increased on coordination with the metal ions thus, introducing a novel class of organometallic-based antibacterial and antifungal agents.
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Hasan A, Khan KM, Sher M, Maharvi GM, Nawaz SA, Choudhary MI, Supuran CT. Synthesis and inhibitory potential towards acetylcholinesterase, butyrylcholinesterase and lipoxygenase of some variably substituted chalcones. J Enzyme Inhib Med Chem 2005; 20:41-7. [PMID: 15895683 DOI: 10.1080/14756360400015231] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
A series of variably substituted chalcones were synthesized by condensation of substituted acetophenones with mono-, di- or trisubstituded benzaldehydes. It was observed that some of these compounds have the potential to inhibit acetylcholinesterase, whereas others show activity against butyrylcholinesterase, depending on the substitution pattern at the two aromatic rings of these chalcones. Similarly, lipoxygenase was inhibited by two of these compounds. It has been observed that inhibition of the three enzymes was concentration dependent with the IC50 values ranging from 28.2-134.5 microM against acetylcholinesterase, 16.0-23.1 microM against butyrylcholinesterase and 57.6-71.7 microM against lipoxygenase, respectively.
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Khan KM, Maharvi GM, Khan MTH, Perveen S, Choudhary MI. A facile and improved synthesis of sildenafil (Viagra) analogs through solid support microwave irradiation possessing tyrosinase inhibitory potential, their conformational analysis and molecular dynamics simulation studies. Mol Divers 2005; 9:15-26. [PMID: 15789547 DOI: 10.1007/s11030-005-1299-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Herein, the synthesis of some analogs of sildenafil (Viagra) (21) is described, employing MW irradiations in key steps such as, SNAr reaction on important precursor bromopyrazole (7). Compound 7 was synthesized by the bromination followed by the amidation of readily available 1-methyl-3-propyl-1H-pyrazole-5-carboxylic acid (5). Compounds 9 and 10 were obtained as SNAr reaction products, apparently through the proposed dipolar high-energy transition states TS-1 and TS-2 under MW irradiation, respectively. In contrast, conventional heating failed to produce similar results, even after prolonged heating. Compound 10, upon chlorosulfonation followed by the coupling of various nucleophiles, yielded a series of compounds 12-20 as analogs of sildenafil (21). Compounds 12-21 were subjected to tyrosinase inhibition studies and SAR studies were carried out. This study reflected that the inhibition was enhanced with increase of carbon chain. In case of the compound 17, the -OH group was replaced with -CH2-CH2-OH with a resulting increase in inhibition against tyrosinase. Compound 17 was found to be more potent than the potent reference inhibitor LM and KA. The 2D and 3D hydrogen bonding descriptors that help to study QSPR were also calculated. Energetically most stable conformations of these compounds were analyzed. Their kinetic, potential and total energies were also calculated through MD simulation.
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Liu-Ambrose T, Khan KM, Eng JJ, Lord SR, McKay HA. Balance confidence improves with resistance or agility training. Increase is not correlated with objective changes in fall risk and physical abilities. Gerontology 2005; 50:373-82. [PMID: 15477698 PMCID: PMC3383061 DOI: 10.1159/000080175] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2003] [Accepted: 01/22/2004] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND While the fear of falling is a common psychological consequence of falling, older adults who have not fallen also frequently report this fear. Fear of falling can lead to activity restriction that is self-imposed rather than due to actual physical impairments. Evidence suggests that exercise can significantly improve balance confidence, as measured by falls-related self-efficacy scales. However, there are no prospective reports that correlate change in balance confidence with changes in fall risk and physical abilities as induced by participating in a group-based exercise program. OBJECTIVE The primary purpose of this prospective study was to examine the relationship between the change in balance confidence and the changes in fall risk and physical abilities in older women with confirmed low bone mass after 13 weeks of exercise participation. The secondary purpose of this study was to examine the relationship between the change in balance confidence and the change in physical activity level. METHODS The sample comprised 98 women aged 75-85 years with low bone mass. Participants were randomly assigned to one of three groups: resistance training (n = 32), agility training (n = 34), and stretching (sham) exercises (n = 32). The 50-min exercise classes for each study arm were held twice weekly at a local YMCA community centre. RESULTS Both resistance training and agility training significantly improved balance confidence by 6% from baseline after 13 weeks. However, the change in balance confidence was only weakly correlated with improved general physical function and not significantly correlated with the changes in fall risk score, postural stability, gait speed, or physical activity level. As well, we observed balance confidence enhancement in the presence of increased fall risk or deterioration in physical abilities. CONCLUSIONS Two different types of exercise training improved balance confidence in older women with low bone mass. This change in balance confidence was significantly correlated with change in general physical function. Because of the observation of discordance between balance confidence change and changes in fall risk and physical abilities, those who design group-based exercise programs for community-dwelling older adults may wish to consider including an education component on factors that influence fear of falling. Objective changes in fall risk factors cannot be assumed to mirror change in fear of falling and physical abilities in older adults in the short-term.
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Scott A, Khan KM, Heer J, Cook JL, Lian O, Duronio V. High strain mechanical loading rapidly induces tendon apoptosis: an ex vivo rat tibialis anterior model. Br J Sports Med 2005; 39:e25. [PMID: 15849278 PMCID: PMC1725204 DOI: 10.1136/bjsm.2004.015164] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND The role of apoptosis, or programmed cell death, has only recently been explored in tendon. OBJECTIVE To investigate the development of apoptosis after high strain loading of rat tendon. METHODS The right tibialis anterior tendons of three rats were prepared for mechanical loading, and left tendons were prepared identically as non-loaded controls. Tendon was loaded with 20% strain for six hours using a 1 Hz longitudinal sine wave signal. The following were used to assess apoptosis: (a) a monoclonal mouse antibody (F7-26) to label single stranded DNA breaks; (b) a rabbit polyclonal antibody that specifically recognises the cleaved form of caspase-3. RESULTS Light microscopy confirmed that the high strain protocol induced a stretch overload injury. Control tendons showed little or no staining with the F7-26 antibody, but the loaded tendons displayed numerous apoptotic cells. The percentage of apoptotic cells (20%) in the loaded tendon was significantly greater than in the control tendon (1%) (p = 0.000). The labelled cells colocalised with abnormal nuclear morphology, including nuclear fragmentation. The staining against cleaved caspase-3 was positive in loaded tendons only, and localised both to nucleus and cytoplasm. CONCLUSION This experiment extends knowledge of human tendon apoptosis by showing that apoptosis can occur in response to short term, high strain mechanical loading. This is the first report of mechanical loading of intact tendon causing excessive apoptosis.
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Scott A, Khan KM, Cook JL, Duronio V. What is "inflammation"? Are we ready to move beyond Celsus? Br J Sports Med 2005; 38:248-9. [PMID: 15155418 PMCID: PMC1724817 DOI: 10.1136/bjsm.2003.011221] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Scott A, Khan KM, Roberts CR, Cook JL, Duronio V. What do we mean by the term "inflammation"? A contemporary basic science update for sports medicine. Br J Sports Med 2005; 38:372-80. [PMID: 15155453 PMCID: PMC1724810 DOI: 10.1136/bjsm.2004.011312] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Most practicing sports medicine clinicians refer to the concept of "inflammation" many times a day when diagnosing and treating acute and overuse injuries. What is meant by this term? Is it a "good" or a "bad" process? The major advances in the understanding of inflammation in recent years are summarised, and some clinical implications of the contemporary model of inflammation are highlighted.
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Purdam CR, Jonsson P, Alfredson H, Lorentzon R, Cook JL, Khan KM. A pilot study of the eccentric decline squat in the management of painful chronic patellar tendinopathy. Br J Sports Med 2005; 38:395-7. [PMID: 15273169 PMCID: PMC1724885 DOI: 10.1136/bjsm.2003.000053] [Citation(s) in RCA: 181] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES This non-randomised pilot study investigated the effect of eccentric quadriceps training on 17 patients (22 tendons) with painful chronic patellar tendinopathy. METHODS Two different eccentric exercise regimens were used by subjects with a long duration of pain with activity (more than six months). (a) Nine consecutive patients (10 tendons; eight men, one woman; mean age 22 years) performed eccentric exercise with the ankle joint in a standard (foot flat) position. (b) Eight patients (12 tendons; five men, three women; mean age 28 years) performed eccentric training standing on a 25 degrees decline board, designed to increase load on the knee extensor mechanism. The eccentric training was performed twice daily, with three sets of 15 repetitions, for 12 weeks. Primary outcome measures were (a) 100 mm visual analogue scale (VAS), where the subject recorded the amount of pain during activity, and (b) return to previous activity. Follow up was at 12 weeks, with a further limited follow up at 15 months. RESULTS Good clinical results were obtained in the group who trained on the decline board, with six patients (nine tendons) returning to sport and showing a significantly reduced amount of pain over the 12 week period. Mean VAS scores fell from 74.2 to 28.5 (p = 0.004). At 15 months, four patients (five tendons) reported satisfactory results (mean VAS 26.2). In the standard squat group the results were poor, with only one athlete returning to previous activity. Mean VAS scores in this group were 79.0 at baseline and 72.3 at 12 weeks (p = 0.144). CONCLUSION In a small group of patients with patellar tendinopathy, eccentric squats on a decline board produced encouraging results in terms of pain reduction and return to function in the short term. Eccentric exercise using standard single leg squats in a similar sized group appeared to be a less effective form of rehabilitation in reducing pain and returning subjects to previous levels of activity.
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Foker JE, Kendall TC, Catton K, Khan KM. A flexible approach to achieve a true primary repair for all infants with esophageal atresia. Semin Pediatr Surg 2005; 14:8-15. [PMID: 15770584 DOI: 10.1053/j.sempedsurg.2004.10.021] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Our purpose is to present our results using a flexible surgical approach to achieve a true primary repair for all infants with esophageal atresia (EA). The proposed methods are designed to reach this goal, even when most of the intrathoracic esophagus is missing. What has made this goal attainable is the ability to rapidly induce esophageal growth. We reviewed the results of 63 consecutive patients who presented between 1984 and 2004 with an esophageal gap of greater than 2.5 cm, a distance where increasingly difficult repairs begin. Gaps of 4 cm or longer (46), 6.0 cm or longer (14), and over 10 cm (3) were included. Repairs begun elsewhere (20) included 17 spit fistulas. We present 3 surgical stages, designed to overcome tension and, for longer gaps, induce esophageal growth. For 25 infants, traction in the operating room was sufficient to dissipate tension and allow a primary repair. For the longest gaps, successful esophageal growth was induced over days in 38 patients by internal (5), external (23), and mixed internal/external traction (10). Growth quickly produced adequate esophagus for a primary repair. We conclude that adequate esophageal growth can be induced within days, even early in infancy, and this flexible approach allows the entire EA spectrum to be repaired primarily.
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Ahmed M, Ahmed N, Khan KM, Umer M, Rashid H, Hashmi P, Umar M. Sensory hypoinnervation in club foot. ACTA ACUST UNITED AC 2004; 86:1163-9. [PMID: 15568531 DOI: 10.1302/0301-620x.86b8.14305] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We have compared the density of nerve fibres in the synovium in club foot with that of specimens obtained from the synovium of the hip at operations for developmental dysplasia. The study focused on the sensory neuropeptides substance P; calcitonin gene-related peptide; protein gene product 9.5, a general marker for mature peripheral nerve fibres; and growth associated protein 43, a neuronal marker for new or regenerating nerve fibres. In order to establish whether there might be any inherent difference we analysed the density of calcitonin gene-related peptide-positive nerve fibres in the hip and ankle joints in young rats. Semi-quantitative analysis showed a significant reduction in the number of sensory and mature nerve fibres in the synovium in club foot compared with the control hips. Calcitonin gene-related peptide (CGRP) positive fibres were reduced by 28%, substance P-positive fibres by 36% and protein gene product 9.5-positive fibres by 52% in club foot. The growth associated protein 43-positive fibres also seemed to be less in six samples of club foot. No difference in the density of CGRP-positive nerve fibres was observed in the synovium between ankle and hip joints in rats. The lack of sensory input may be responsible for the fibrosis and soft-tissue contractures associated with idiopathic club foot.
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