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Hasan Z, Shah BH, Mahmood A, Young DB, Hussain R. The effect of mycobacterial virulence and viability on MAP kinase signalling and TNF alpha production by human monocytes. Tuberculosis (Edinb) 2003; 83:299-309. [PMID: 12972343 DOI: 10.1016/s1472-9792(03)00003-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
SETTING The success of Mycobacterium tuberculosis as a human pathogen depends on its ability to tolerate and perhaps manipulate host defense mechanisms. OBJECTIVE To determine the induction of tumour necrosis factor-alpha (TNF alpha), a central mediator of immunity, by human monocytes infected with virulent M. tuberculosis, M. leprae and attenuated M. bovis BCG. DESIGN Mycobacteria-induced cellular activation pathways of TNF alpha production was investigated using an inhibitor of protein tyrosine kinase (PTKs) and an inhibitor of mitogen-activated protein (MAP) kinases. RESULTS TNF alpha production was significantly lower during infection with virulent M. tuberculosis than with BCG and this differential response was independent of mycobacterial viability. TNF alpha production involved the PTK and MAP kinase pathways. Reduced TNF alpha induction by M. tuberculosis was associated with a reduction in the extent and duration of phosphorylation of extracellular-signal regulated kinases (ERK 1/2). Infection with M. leprae triggered low and transient ERK 1/2 activation as well as low TNF alpha production. CONCLUSION Maintenance of the differential response in both live and heat-killed preparations suggests that the reduced TNF alpha response associated with virulent mycobacteria is due to differences in the presence of components capable of triggering host pattern recognition receptors, rather than events associated with phagosome trafficking or the active release of intracellular modulators.
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Afsar HA, Qureshi AF, Younus M, Gulb A, Mahmood A. Factors affecting unsuccessful referral by the Lady Health Workers in Karachi, Pakistan. J PAK MED ASSOC 2003; 53:521-8. [PMID: 14738257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
OBJECTIVE To estimate the proportion of patient referral and to identify the factors associated with unsuccessful referral in Karachi, Pakistan. METHODS In a cross-sectional survey, a total of 347 patients referred to different health care facilities by the LHWs were interviewed. Data was collected using a structured questionnaire, on demographic characteristics of patients (age, sex, income etc) and potential factors (seriousness of medical condition, distance of health facility, attitude of health center staff etc) that can affect patient referral outcome. RESULTS An overall referral rate of 55% was found in this study. Out of a total of 347 patients interviewed, 265 (76.4%) were successful while 82 (23.6%) were unsuccessful referrals. Multivariate logistic regression analysis showed that objection to referral (Adjusted OR, 2.96; CI: 1.44-5.52), never referred before (Adjusted OR, 1.25; CI: 1.34-6.90), not visited the referral site before (Adjusted OR, 4.04; CI: 2.50-6.08) and no knowledge of who to meet at the referral site (Adjusted OR, 1.30; CI: 1.01-2.96) were the factors associated with unsuccessful referral. Other factors found significant were duration of the illness of the patient, anyone not known at the referral site and failure of LHW to follow up. CONCLUSION Our study found that a significant proportion of patients seen by the LHWs are referred to different health facilities. Improved management skills of LHWs for simple medical problems would probably reduce the number of referrals. Efforts should also be directed to enhance the communication and counseling skills of LHWs, which may reduce a significant proportion of unsuccessful referrals.
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Bolzati C, Mahmood A, Malagò E, Uccelli L, Boschi A, Jones AG, Refosco F, Duatti A, Tisato F. The [99mTc(N)(PNP)]2+ Metal Fragment: A Technetium-Nitrido Synthon for Use with Biologically Active Molecules. The N-(2-Methoxyphenyl)piperazyl-cysteine Analogues as Examples. Bioconjug Chem 2003; 14:1231-42. [PMID: 14624640 DOI: 10.1021/bc034100g] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The incorporation of a bioactive molecule into a nitrido-containing (99m)Tc-complex has been successfully achieved by using the [TcN(PNP)](2+) metal fragment. In this strategy, the strong electrophilic [TcN(PNP)](2+) metal fragment efficiently reacts with bifunctional chelating ligands having a pi-donor atom set, such as N-functionalized O,S-cysteine. The 2-methoxyphenylpiperazine (2-MPP) pharmacophore, which displays preferential affinity for 5HT(1A) receptors, was conjugated to the amino group of cysteine to obtain 2-MPPP-cys-OS, where 2-MPPP is 3-[4-(2-methoxyphenyl)piperazin-1-yl]propionate. The asymmetric Tc(V)-nitrido complexes, [(99g/99m)Tc(N)(PNP)(2-MPPP-cys-OS)] (PNP = PNP3, PNP4), were obtained in high yield (95%), by simultaneous addition of PNP and 2-MPPP-cys-OS ligand to a solution containing a starting (99g)/(99m)Tc-nitrido precursor. A mixture of syn and anti isomers was observed, the latter being the thermodynamically favored species. In vitro challenge experiments using the anti isomers with glutathione and cysteine indicated that no transchelation reaction occurs. Assessment of the in vitro 5HT(1A) receptor-affinity of the technetium complexes revealed that only the anti-PNP4 complex possesses some affinity for the receptor, but displayed negligible brain uptake in biodistribution studies in rats in vivo.
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Mahmood A, Sintler M, Edwards AT, Smith SRG, Simms MH, Vohra RK. The efficacy of aspirin in patients undergoing infra-inguinal bypass and identification of high risk patients. INT ANGIOL 2003; 22:302-7. [PMID: 14612858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
AIM Infrainguinal bypass is an effective treatment for critical lower limb ischemia but up to 1/3 of these grafts will occlude within the 1st year. The aim of this audit was to evaluate the efficacy of aspirin in maintaining graft patency and also improving patient survival. METHODS In a single audited year (1997) 125 bypasses were carried out. Seventy-nine were on aspirin, 34 on no treatment and 12 were on other agents and hence excluded from analysis. The indication for surgery was critical ischaemia in 101 and disabling claudication in 12. Autologous vein was used in 104 and prosthetic grafts in 9. RESULTS The overall 2-year primary graft patency, secondary graft patency and limb salvage were 50%, 71% and 83%, respectively. The 2-year secondary patency in patients with or without aspirin was 73% and 64%, respectively (p<0.12-log rank test). The corresponding patient survival from vascular death in the 2 groups was 73% and 70% (p<0.67-log rank test). Crural/ pedal bypass (51/75 on aspirin) and smoking (51/61 on aspirin) were independent risk factors for graft failure and vascular death respectively whilst those with a previous myocardial infarct (21/28 on aspirin) reached significance in univariate analysis only (p< 0.03). CONCLUSION Aspirin was not a significant factor in preventing graft failure or vascular death in patients undergoing bypass for critical limb ischemia. Dual therapy with other antiplatelet agents needs to be considered in such patients particularly those undergoing crural/pedal bypass, smokers and those with a history of previous myocardial infarction.
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Butt T, Kazmi SY, Ahmad RN, Mahmood A, Karamat KA, Anwar M. Frequency and antibiotic susceptibility pattern of mycobacterial isolates from extra-pulmonary tuberculosis cases. J PAK MED ASSOC 2003; 53:328-32. [PMID: 14558735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
OBJECTIVE To determine the frequency and antimicrobial susceptibility pattern of extra-pulmonary tuberculosis in Rawalpindi. SETTING Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi. METHODS Between September 2000 and August 2002, 899 pulmonary and 460 extra-pulmonary specimens from suspected cases of tuberculosis were examined. The radiometric BACTEC 460 TB system was used for culture and antimicrobial susceptibility testing. RESULTS Mycobacteria were isolated from 291 pulmonary specimens and 98 extra-pulmonary specimens. The frequency of extra-pulmonary tuberculosis was 25.2%. The commonest source of isolation was pus (44.9%, frequency 11.3%), followed by lymph nodes (13.3%, frequency 3.3%) and pleural fluid (13.3%, frequency 3.3%). We tested the anti-microbial susceptibility of the isolates to the four first line anti-tuberculous drugs, rifampicin, isoniazid, streptomycin and ethambutol. Of the extra-pulmonary isolates 13.3% were resistant to a single drug, 21.4% were multi-drug resistant and 9.2% were resistant to all the four drugs. CONCLUSION Increased awareness of the magnitude of the problem posed by extra-pulmonary tuberculosis is required so that appropriate control measures can be adopted.
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Mahmood A, Shao JS, Alpers DH. Rat enterocytes secrete SLPs containing alkaline phosphatase and cubilin in response to corn oil feeding. Am J Physiol Gastrointest Liver Physiol 2003; 285:G433-41. [PMID: 12660142 DOI: 10.1152/ajpgi.00466.2002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Surfactant-like particles (SLP) are unilamellar secreted membranes associated with the process of lipid absorption and isolated previously only from the apical surface of enterocytes. In this paper, the intracellular membrane has been isolated from corn oil-fed animals, identified by its content of the marker protein intestinal alkaline phosphatase (IAP). Another brush-border protein, cubilin, and its anchoring protein megalin have been identified as components of extracellular SLP, but only cubilin is present to any extent in intracellular SLP. During fat absorption, IAP is modestly enriched in intracellular SLP, but full-length cubilin (migrating at 210 kDa in fat-fed mucosal fractions) falls by one-half, although fragments of cubilin are abundant in the intracellular SLP. Both IAP and cubilin colocalize to the same cells during corn oil absorption and colocalize around lipid droplets. This localization is more intense during feeding of corn oil with Pluronic L-81, a detergent that allows uptake of fatty acids and monoglycerides from the lumen, but blocks chylomicron secretion. Confocal microscopy confirms the colocalization of IAP and the ligand for cubilin, intrinsic factor. Possible roles for cubilin in intracellular SLP include facilitating movement of the lipid droplet through the cell and binding to the basolateral membrane before reverse endocytosis.
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Mahmood A, Hardy R, Garnham A, Samman Y, Sintler M, Smith SRG, Vohra RK, Simms MH. Microtibial embolectomy. Eur J Vasc Endovasc Surg 2003; 25:35-9. [PMID: 12525809 DOI: 10.1053/ejvs.2002.1768] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND microtibial embolectomy is an important technique in cases of limb threatening acute arterial occlusion affecting native crural and pedal vessels. It is particularly useful when thrombolysis is contraindicated or ineffective as in "trash foot". METHODS in order to evaluate the efficacy of this technique, a retrospective case note review was carried out for patients undergoing microtibial embolectomy from 1990 to 1999. Data collected included the causes and degree of ischaemia, additional procedures required, vessel patency, limb salvage and complications encountered. RESULTS twenty-two limbs underwent exploration of the crural/pedal vessels with ankle level arteriotomies under local anaesthetic in 12 cases, general anaesthetic in nine and epidural in one. The causes of ischaemia were cardiac emboli (8), "trash foot" (7), emboli from aortic and popliteal aneurysms (3) and thrombotic occlusion of crural vessels (4). The vessel patency rate was 69% and limb salvage rate 62% (13/21) up to 5-years follow-up. Six of the seven cases with "trash foot" were salvaged while one required an amputation at 3-months post-operatively. The 30-day mortality was 22% (5/22). CONCLUSIONS microtibial embolectomy is effective in acute occlusion of the crural/pedal arteries including cases of "trash foot", offering limb salvage to a worthwhile proportion of cases.
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Mahmood A. Composite sequential grafts for femorocrural bypass reconstruction: Experience with a modified technique. J Vasc Surg 2002. [DOI: 10.1016/s0741-5214(02)00132-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Mahmood A, Karamat KA, Butt T. Neonatal sepsis: high antibiotic resistance of the bacterial pathogens in a neonatal intensive care unit in Karachi. J PAK MED ASSOC 2002; 52:348-50. [PMID: 12481673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To study the bacterial pathogens causing neonatal sepsis and their sensitivity pattern so that guidelines can be prepared for empirical antibiotic therapy. SETTING The study was conducted in the neonatal intensive care unit (NICU) at PNS Shifa (Naval Hospital), Karachi during January 1997 to June 1999. METHODS Blood specimens for culture were drawn from 520 newborns admitted in a NICU with sepsis. The specimens were inoculated into brain heart infusion broth. Subcultures were performed on days 1, 2, 3, 5, 7 and 10. The isolates were identified by standard biochemical tests. Antibiotic resistance pattern of the isolates was studied by Modified Kirby Baur disc diffusion technique. RESULTS A total of 212 organisms were isolated. These included Staphylococcus aureus (n = 65), Klebsiella pneumoniae (n = 73), Acinetobacter baumannii (n = 23), Escherichia coli (n = 22), Enterobacter cloacae (n = 18), Citrobacter diversus (n = 5), Pseudomonas aeruginosa (n = 4) and group B Streptococcus (n = 2). On antibiotic sensitivity testing, 61.54% of Staphylococcus aureus isolates were found to be methicillin resistant. Susceptibility to the other common drugs was also quite low while 89.23% of these were susceptible to amikacin and 100% to vancomycin. More than 90% gram negative rods were resistant to ampicillin and co-trimoxazole. Resistance to gentamicin was as high as 90.4% for Klebsiella pneumoniae; 60.87% for Acinetobacter baumannii. Resistance to the third generation cephalosporins and the quinolone tested (ciprofloxacin) varied between 25-75%. Majority of the isolates were susceptible to meropenem and amikacin. CONCLUSION In view of the isolation of highly antibiotic resistant organisms, vancomycin in combination with amikacin or a carbapenem is the drug of choice for empirically treating neonatal sepsis.
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Mahmood A, Engle MJ, Alpers DH. Secreted intestinal surfactant-like particles interact with cell membranes and extracellular matrix proteins in rats. J Physiol 2002; 542:237-44. [PMID: 12096065 PMCID: PMC2290410 DOI: 10.1113/jphysiol.2002.017087] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Surfactant-like particles (SLP) are secreted from enterocytes basolaterally into the lamina propria, and reach the apical surface through the intercellular tight junctions. Interactions of SLP with apical and basolateral membranes and with extracellular matrix proteins were measured using a solid-phase binding assay and gel overlays. Small-intestinal SLP bound to basolateral membranes much more than to apical membranes, and more tightly to fibronectin than to laminin (affinity constant K(a) = 1.23 x 10(-2) microg vs. 0.67 x 10(-2) microg; maximal number of binding sites 4.1 microg x ml(-1) vs. 0.32 microg x ml(-1)), but did not bind to collagen types I or IV. Small-intestinal SLP bound fibronectin more than colonic or gastric SLP. Binding to fibronectin was inhibited only partially by RGD peptide and gelatin, but not by heparin. An antibody against alpha(v) integrin also identified the fibronectin-binding component in SLP at approximately 220 kDa, which is the expected size for integrin heterodimers. SLP binding to apical microvillous membranes was weaker and was inhibited by heparin. SLP bound more strongly to heparin itself, and this binding was inhibited by glucuronic acid and chondroitin sulfate. These data are consistent with the hypothesis that the time spent by secreted SLP in the lamina propria is prolonged by strong interactions with proteins in the basolateral membranes, and in the intestinal lumen by weaker interactions with apical membrane components, including heparin. These interactions may allow SLP the time to exert their functions in each tissue compartment.
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Pathak A, Mahmood A, Pathak R, Dhawan D. Effect of zinc on hepatic lipid peroxidation and antioxidative enzymes in ethanol-fed rats. J Appl Toxicol 2002; 22:207-10. [PMID: 12015801 DOI: 10.1002/jat.851] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A 3-ml aliquot of 30% ethanol was fed daily to normal as well as zinc-treated (227 mg l(-1)) rats for periods of 2, 4 and 8 weeks. A highly significant increase in the levels of hepatic lipid peroxidation was observed in ethanol-fed rats after 4 and 8 weeks of treatment. On the other hand, the levels of lipid peroxidation came down significantly following ethanol feeding to zinc-treated rats. The activities of glutathione peroxidase (GPx), catalase and superoxide dismutase (SOD) in liver were elevated significantly after ethanol administration to rats for durations of 2, 4 and 8 weeks. Interestingly, zinc treatment to rats given ethanol was able to bring down the elevated levels of SOD, catalase and GPx to within normal limits, However, zinc administration alone did not cause any significant alteration in the activities of these antioxidative enzymes.
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Byers W, Cossham JA, Edwards JO, Gordon AT, Jones JG, Kenny ETP, Mahmood A, McKnight J, Sweigart DA. Hydrogen bonding in metalloporphyrins. Mechanistic study of the reactions of (tetraphenylporphinato)iron(III) azide with imidazole and N-methylimidazole. Inorg Chem 2002. [DOI: 10.1021/ic00246a036] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Anderson VE, Cheng HZ, Diebold GJ, Mahmood A, Sweigart DA. Chemical kinetics in dilute solution: photoacoustic detection of small absorbance changes in chemical reactions. J Am Chem Soc 2002. [DOI: 10.1021/ja00254a053] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Kalra S, Mahmood S, Nagpaul JP, Mahmood A. Changes in the chemical composition of surfactant-like particles secreted by rat small intestine in response to different dietary fats. Lipids 2002; 37:463-8. [PMID: 12056587 DOI: 10.1007/s11745-002-0918-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Consumption of dietary oil, viz., corn, fish, coconut, or olive, induced the secretion of surfactant-like particles (SLP) in rat intestine. These lipoprotein particles differ in (i) levels of alkaline phosphatase activity, (ii) lipid composition, and (iii) FA composition in response to feeding of different oils. The secreted particles had similar buoyancy (1.07-1.08 g/mL) and cholesterol/phospholipid molar ratios (0.61-0.72) except that feeding coconut oil to rats produced SLP with a low (0.18) cholesterol/phospholipid molar ratio compared to control animals. It is concluded from these observations that feeding different oils induces the secretion of lipoprotein particles in rat intestine with different chemical compositions.
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Kaur N, Kaur J, Mahmood A. Effect of harmaline on rat intestinal brush border sucrase activity. INDIAN JOURNAL OF BIOCHEMISTRY & BIOPHYSICS 2002; 39:119-123. [PMID: 22896899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The effect of harmaline, a plant alkaloid has been studied on rat intestinal brush border sucrase activity. Stimulation of sucrase activity by Na+ was found to be pH-dependent. At neutral pH, 20 mM Na+ stimulated sucrase activity by reducing K(m) by 30%, while at acidic pH (5.2), the activity increased 4-fold compared to Na+-free enzyme. At 1.0 mM, harmaline markedly inhibited (67%) the enzyme activity at pH 5.2 in the absence of Na+. However, inhibition was reduced in presence of 20 mM sodium, whereas 4.0 mM harmaline was required to inhibit the enzyme activity by 65%. In the absence of Na+ ions, harmaline inhibition of sucrase activity was of competitive type, but it changed to non-competitive type in presence of 20 mM Na+ at pH 5.2. Sucrase-harmaline interactions as a function of pH, both in presence and absence of Na+ revealed a shift in pH optima of the enzyme towards a higher pH in presence of 4 mM and 1 mM harmaline respectively. The observed inhibition was reversible in nature and was only partially overcome by sodium, lithium, potassium, cesium, rubidium and ammonium ions. These findings suggest that harmaline also inhibits rat brush border sucrase and that the presence of Na+ site is not a pre-requisite for the inhibition.
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Farmer A, Redman K, Harris T, Webb R, Mahmood A, Sadler S, McGuffin P. The Cardiff sib-pair study: suicidal ideation in depressed and healthy subjects and their siblings. CRISIS 2002; 22:71-3. [PMID: 11727897 DOI: 10.1027/0227-5910.22.2.71] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
Depression is associated with high rates of suicidal ideation, which varies in intensity from transient thoughts of wishing to be dead to the making of plans and, Finally, to attempts to kill oneself. There is limited evidence from family, twin, and adoption studies that completed suicide is familial and has a genetic etiological component. However, it is unclear whether suicidal ideation is also familial. The familiality of suicidal ideation has been examined in the subjects who participated in the Cardiff Depression Study, namely, 108 depressed probands. their nearest-aged siblings, and 105 healthy control subjects and their siblings. The study showed that 66% of depressed subjects had experienced suicidal ideation in the week prior to the interview, and that this was significantly associated with recurrent illness. Suicidal ideation was not shown to be familial. However, somewhat surprisingly, 6% of healthy, never-depressed subjects admitted to having had transient suicidal thoughts. Suicidal ideation was significantly associated with high neuroticism and psychoticism scores and severe threatening life events.
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Zaheer A, Lenkinski RE, Mahmood A, Jones AG, Cantley LC, Frangioni JV. In vivo near-infrared fluorescence imaging of osteoblastic activity. Nat Biotechnol 2001; 19:1148-54. [PMID: 11731784 DOI: 10.1038/nbt1201-1148] [Citation(s) in RCA: 286] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In vertebrates, the development and integrity of the skeleton requires hydroxyapatite (HA) deposition by osteoblasts. HA deposition is also a marker of, or a participant in, processes as diverse as cancer and atherosclerosis. At present, sites of osteoblastic activity can only be imaged in vivo using gamma-emitting radioisotopes. The scan times required are long, and the resultant radioscintigraphic images suffer from relatively low resolution. We have synthesized a near-infrared (NIR) fluorescent bisphosphonate derivative that exhibits rapid and specific binding to HA in vitro and in vivo. We demonstrate NIR light-based detection of osteoblastic activity in the living animal, and discuss how this technology can be used to study skeletal development, osteoblastic metastasis, coronary atherosclerosis, and other human diseases.
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Mahmood A, Lu D, Wang L, Li Y, Lu M, Chopp M. Treatment of traumatic brain injury in female rats with intravenous administration of bone marrow stromal cells. Neurosurgery 2001; 49:1196-203; discussion 1203-4. [PMID: 11846913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2001] [Accepted: 06/04/2001] [Indexed: 02/23/2023] Open
Abstract
OBJECTIVE To study the effect of bone marrow stromal cells administered intravenously to female rats subjected to traumatic brain injury. METHODS We injected marrow stromal cells harvested from male rat bone marrow (n = 24) into the tail vein of the female rat (n = 8) 24 hours after traumatic brain injury; the rats were killed at Day 7 or 14 after treatment. The neurological function of the rats was evaluated using the rotarod test and the neurological severity score. The distribution of the male donor cells in brain, heart, lung, kidney, liver, muscle, spleen, and bone marrow of the female recipient rats was measured by identifying Y chromosome-positive cells using fluorescent in situ hybridization. RESULTS We found that marrow stromal cells injected intravenously significantly reduced motor and neurological deficits compared with control groups by Day 15 after traumatic brain injury (P < 0.05, analysis of covariance for repeated measures). The transplanted cells preferentially engrafted into the parenchyma of the injured brain and expressed the neuronal marker NeuN and the astrocytic marker glial fibrillary acidic protein. Marrow stromal cells were also found in other organs in female rats subjected to traumatic brain injury without any obvious adverse effects. CONCLUSION These data suggest that the intravenous administration of marrow stromal cells may be a promising therapeutic strategy that warrants further investigation for patients with traumatic brain injury.
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Labana S, Bansal RC, Mahmood A. Effects of endosulfan on intestinal functions in protein-malnourished rats. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 2001; 39:1017-21. [PMID: 11883509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
In rats fed 18% protein diet, administration of endosulfan (2mg/kg body weight daily for 7 days) significantly decreased the brush border sialic acid and increased the hexoses contents. The intestinal uptake of glucose was increased while that of glycine and calcium was reduced. Brush border enzymes and lipids were not affected. However, in protein malnourished rats (fed 8% protein) exposed to endosulfan, brush border sucrase and peptidase activities were enhanced, while alkaline phosphatase activity was decreased compared to untreated malnourished animals. Membrane sialic acid content was low while fucose and cholesterol levels were augmented in endosulfan fed malnourished animals. The uptake of glucose and glycine was elevated under these conditions. These results Suggest that the nutritional status of the animals has an important bearing on thc susceptibility of intestinal tissue to endosulfan toxicity in rats.
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Friebe M, Mahmood A, Bolzati C, Drews A, Johannsen B, Eisenhut M, Kraemer D, Davison A, Jones AG. [99mTc]oxotechnetium(V) complexes amine-amide-dithiol chelates with dialkylaminoalkyl substituents as potential diagnostic probes for malignant melanoma. J Med Chem 2001; 44:3132-40. [PMID: 11543682 DOI: 10.1021/jm0005407] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[99mTc]oxotechnetium(V) complexes of amine-amide-dithiol (AADT) chelates containing tertiary amine substituents were synthesized and shown to have affinity for melanoma. For complexation the AADT-CH2[CH2]nNR2 (n = 1, 2; R = Et, n-Bu) ligand was mixed with a [99mTc]oxotechnetium(V)-glucoheptonate precursor to make the AADT-[99mTc]oxotechnetium(V) complexes in nearly quantitative yield. Structurally analogous nonradioactive oxorhenium(V) complexes were also synthesized and characterized. In vitro sigma-receptor affinity measurements indicate these complexes to possess sigma-affinity in the low micromolar range with K(i) values in the 7.8-26.1 and 0.18-2.3 microM range for the sigma1- and sigma2-receptors, respectively. In vitro cell uptake of the 99mTc complexes in intact B16 murine melanoma cells at 37 degrees C after a 60-min incubation ranged from 12% for complex 2 (n = 1, R = n-Bu) to 68% for complex 4 (n = 2, R = n-Bu). In vivo evaluation of complexes 1-Tc-4-Tc in the C57Bl/B16 mouse melanoma model demonstrated significant tumor localization. Complex 1-Tc (n = 1, R = Et) displayed an in vivo tumor uptake of 7.6% ID/g at 1 h after administration with initial melanoma/blood (M/B), melanoma/spleen (M/S), and melanoma/lung (M/L) ratios >4; these ratios increased to 10.8, 10.1, and 7.3, respectively, at 6 h. While complex 3-Tc (n = 3, R = Et) had an initial tumor uptake of 3.7% ID/g 1 h after administration with M/B, M/S, and M/L ratios >2, a greater tumor retention and slightly faster clearance from nontumor-containing organs resulted in M/B, M/S, and M/L ratios of 19.1, 19.1, and 12.7, respectively, at 6 h. The high tumor uptake and significant tumor/nontumor ratios indicate that such small technetium-99m-based molecular probes can be developed as in vivo diagnostic agents for melanoma and its metastases.
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Gosling P, Rittoo D, Manji M, Mahmood A, Vohra R. Hydroxyethylstarch as a risk factor for acute renal failure in severe sepsis. Lancet 2001; 358:581; author reply 582. [PMID: 11526921 DOI: 10.1016/s0140-6736(01)05718-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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197
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Labana S, Bansal RC, Mahmood A. Age related effects of organochlorine insecticide lindane on intestinal brush border membrane in rats. INDIAN JOURNAL OF BIOCHEMISTRY & BIOPHYSICS 2001; 38:249-52. [PMID: 11811620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
The effect of oral administration of lindane (gamma-HCH) has been studied on the intestine in 10-day, 20-day and 100-day old rats. In 10 day-old suckling pups exposed to lindane, there was a significant decrease in the activities of sucrase (29%), lactase (20%) and that of alkaline phosphatase (24%) compared to control. Sialic acid content of the brush borders was significantly decreased (29%) in 10-day old as well as in 20- and 100-day old rats (20 and 25% respectively), while fucose content of the membranes was significantly enhanced in all the age groups upon pesticide treatment. Among the brush border lipids, cholesterol content was significantly increased in all the age groups studied, the maximum increase of 35% being observed in 10-day-old rats. Membrane phospholipids were also increased in 20- and 100-day old animals (22% each) on lindane exposure. The present studies indicated that brush border membranes of suckling rat intestine were more susceptible to pesticide induced changes compared to older animals.
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198
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Abstract
Pericranium is frequently used in duraplasty and is considered superior to the many other alternatives because of its easy availability and because it offers a watertight dural closure while minimizing the problems of adhesion, infection, and rejection. Although the osteogenic potential of all periosteal tissues is recognized, a review of the literature did not reveal a reported case of osseous formation following use of pericranium for duraplasty. The authors report the case of a 17-year-old man who presented with a self-inflicted gunshot wound to the head. He was obtunded, but moving all extremities purposefully. Computerized tomography scanning demonstrated bifrontal injury. A bicoronal craniotomy with debridement was performed on an emergency basis, with vascularized pericranium used for a duraplasty. Follow-up cranioplasty demonstrated significant ossification of the pericranium 5 months after the original surgery. Pericranium is an attractive material for duraplasty; however, its osteogenic potential may interfere with future cranioplasty and cosmesis. This may be especially relevant in young persons.
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199
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Lu D, Li Y, Wang L, Chen J, Mahmood A, Chopp M. Intraarterial administration of marrow stromal cells in a rat model of traumatic brain injury. J Neurotrauma 2001; 18:813-9. [PMID: 11526987 DOI: 10.1089/089771501316919175] [Citation(s) in RCA: 173] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
To test the efficacy of various delivery routes of stem cells to treat cerebral injury, we investigated the parenchymal distribution of marrow stromal cells (MSCs) injected into the internal carotid artery (ICA) of the adult rat after traumatic brain injury (TBI). Bromodeoxyuridine (BrdU)-labeled MSCs were injected via the ipsilateral ICA at 24 h after TBI. Using histology and immunohistochemistry, the distribution of implanted MSCs was analyzed at 7 days after transplantation. Four groups (n = 4/group) were studied: group 1, animals transplanted with MSCs cultured with NGF and BDNF at 24 h after TBI; group 2, animals transplanted with MSCs cultured without NGF and BDNF; group 3, animals injected with a placebo, phosphate buffered saline into the ICA at 24 h after TBI; and group 4, rats subjected to TBI only. In groups 1 and 2, BrdU-positive cells were localized to the boundary zone of the lesion, corpus callosum and cortex of the ipsilateral hemisphere. The number of BrdU-positive cells was significantly higher in the ipsilateral hemisphere than in the contralateral hemisphere. More MSCs infused intraarterially engrafted in group 1 (18.9%) than in group 2 (14.4%, p < 0.05). Using double staining, BrdU-positive cells expressed MAP-2, NeuN, and GFAP in both groups 1 and 2, with this expression being greater in group 1 and the difference between two groups reaching statistical significance in case of MAP-2. Our data suggest that intraarterial transplantation of MSCs is a viable route for the intracerebral administration of MSCs for the treatment of TBI, since MSCs infused intraarterially after TBI survive and migrate into the brain. Some implanted MSCs express proteins specific to neurons and astrocytes. The addition of NGF and BDNF promote migration of MSCs into the brain and subsequent expression of neuronal protein MAP-2.
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200
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Kumar S, Mahmood S, Nagpaul JP, Mahmood A. Formation of surfactant-like-particle in rat intestine following chronic ethanol feeding. INDIAN JOURNAL OF EXPERIMENTAL BIOLOGY 2001; 39:767-71. [PMID: 12018577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
Ethanol feeding to rats daily for 40 days induces the secretion of surfactant-like-particles in intestine. The isolated lipoprotein particles were enriched with alkaline phosphatase activity and had high phosphatidylcholine content. There was no difference in disaccharidases activities associated with the particles from control and ethanol fed rats. These results suggest that ethanol induced surfactant-like-particles in rat intestine.
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