PubMed Health⌕ Search

Biomedical subjects

Issam Moussa

Publications and source records attributed to Issam Moussa.

48 records · Page 3Linked to original sources
PubMed2003

A Middle Miocene hominoid from Thailand and orangutan origins.

The origin of orangutans has long been debated. Sivapithecus is considered to be the closest ancestor of orangutans because of its facial-palatal similarities, but its dental characteristics and postcranial skeleton do not confirm this phylogenetic position. Here we report a new Middle Miocene hominoid, cf. Lufengpithecus chiangmuanensis n. sp. from northern Thailand. Its dental morphology relates it to the Pongo clade, which includes Lufengpithecus, Sivapithecus, Gigantopithecus, Ankarapithecus and possibly Griphopithecus. Our new species displays striking dental resemblances with living orangutans and appears as a more likely candidate to represent an ancestor of this ape. In addition, it originates from the geographic area of Pleistocene orangutans. But surprisingly, the associated flora shows strong African affinities, demonstrating the existence of a temporary floral and faunal dispersal corridor between southeast Asia and Africa during the Middle Miocene, which may have played a critical role in hominoid dispersion.

Africa↗
PubMed2003

Impact of angina class on inhibition of platelet aggregation following clopidogrel loading in patients undergoing coronary intervention: do we need more aggressive dosing regimens in unstable angina?

Pretreatment with thienopyridines has been shown to improve clinical outcomes in patients undergoing percutaneous coronary intervention (PCI). We determine the impact of angina class on inhibition of platelet aggregation (IPA) following clopidogrel loading. Seventy-two patients (mean age, 64 +/- 11 years; 76% male) were pretreated with 450 mg of clopidogrel at least 3 hr prior to PCI. All patients received ASA 325 mg prior to the procedure. Patients were classified into two groups according to angina class: group 1 = stable angina or Braunwald class 1 unstable angina (UA; n = 33); group 2 = Braunwald class 2 or 3 UA (n = 39). IPA was measured prior to PCI, with the Ichor point-of-care platelet analyzer (Helena Laboratories, Beaumont, TX), using 20 microM of ADP. Group 2 patients were more likely to have prior MI (54% vs. 27%; P = 0.023), prior CABG (33% vs. 5%; P = 0.046), and received IV heparin (64% vs. 27%; P = 0.0018). Mean IPA was significantly lower in group 2 compared to group 1 (19% +/- 22% vs. 32% +/- 22%; P = 0.004). In multivariate analysis, higher angina class was independently associated with lower IPA (P = 0.018). Patients with UA undergoing PCI have a lower IPA following clopidogrel loading with 450 mg. This may indicate the possibility of clopidogrel resistance in such patients.

Angina, Unstable↗
PubMed2002

Effect of catheter-based iridium-192 gamma brachytherapy on the added risk of restenosis from diabetes mellitus after intervention for in-stent restenosis (subanalysis of the GAMMA I Randomized Trial).

Catheter-based intracoronary radiation therapy using iridium-192 (Ir-192) has been shown to be effective in reducing recurrent coronary restenosis after initial percutaneous treatment of in-stent restenosis. Patients with diabetes mellitus (DM) have a higher risk of recurrent restenosis than nondiabetics for nonstented and in-stent restenosis coronary lesions. The use of Ir-192 for preventing recurrent restenosis in such patients remains undefined. The GAMMA I trial was a prospective, randomized, double-blind, multicenter trial of 252 patients with in-stent restenosis who underwent percutaneous coronary intervention and were assigned to receive either Ir-192 (131 patients) or catheter-based placebo (121 patients). DM was present in 79 patients (31%) (41 patients received Ir-192 and 38 patients received placebo) and was absent in 173 patients (90 patients received Ir-192 and 83 patients received placebo). At 6-month follow-up in the GAMMA I trial, the angiographic in-lesion binary restenosis rate was lower in the Ir-192 arm than in the placebo arm (32.4 vs 55.3, p = 0.01). When patients were stratified by the presence of DM, the antirestenosis effect of Ir-192 was larger for diabetic patients than for nondiabetic patients (absolute in-lesion restenosis rate was reduced by 40% for diabetics and 16% for nondiabetics). Thus, adjunctive Ir-192 intracoronary radiation therapy reduces recurrent restenosis after intervention for in-stent restenosis in patients with and without DM. The relative impact of this treatment is more pronounced in diabetic patients because it appears to neutralize the added risk of recurrent restenosis seen in proliferative diabetic lesions.

Brachytherapy↗
PubMed2002

Recent developments in food characterization and adulteration detection: technique-oriented perspectives.

This review covers mainly publications that appeared in Analytical Abstracts (Royal Society of Chemistry) from January 1990 to February 2001. The number of publications on this topic continues to grow, and during the past three years (1998-2000) about 150 reviews and/or overviews have been published in the area of food. Numerous techniques and food matrices or chemical components are presented and discussed in these reviews. The present review is intentionally limited to eight techniques or classes of techniques and intends to be a "technique by technique" presentation of "what was used" or "what is used" to characterize food products and to detect their possible adulteration. The present review focuses on the following techniques: microscopic analysis; HPLC; GC, GC-(MS, FTIR); UV-visible spectrophotometry; AAS/AES, ICP-(AES, MS); IRMS, GC-IRMS, GC-C-IRMS; DSC; IR, mid-IR, and NMR (202 references). Emphasis is placed as much as possible on chemometrical treatment of analytical data, which are commonly used to achieve the final objective, either food characterization or adulteration detection. Finally, a brief description is given of the new generation of analytical systems that combine powerful analytical techniques and powerful computer software for a best extraction of the information from analytical data.

Calorimetry, Differential Scanning↗
PubMed2002

Meta-analysis of randomized and registry comparisons of ticlopidine with clopidogrel after stenting.

OBJECTIVES: We sought to determine whether clopidogrel is at least as efficacious as ticlopidine. BACKGROUND: Several trials have supported the enhanced safety and tolerability of clopidogrel compared with ticlopidine after coronary stent deployment. However, none of these individual trials were powered to detect possible differences in the efficacy for reducing ischemic end points. METHODS: Published data from trials and registries that compared clopidogrel with ticlopidine in patients receiving coronary stents were pooled, and a formal meta-analysis was performed. The rate of 30-day major adverse cardiac events (MACE), as defined in each trial, was used as the primary end point. RESULTS: There were a total of 13,955 patients. The pooled rate of major adverse cardiac events was 2.10% in the clopidogrel group and 4.04% in the ticlopidine group. After adjustment for heterogeneity in the trials, the odds ratio (OR) of having an ischemic event with clopidogrel, as compared with ticlopidine, was 0.72 (95% confidence interval [CI] 0.59 to 0.89, p = 0.002). Mortality was also lower in the clopidogrel group compared with the ticlopidine group-0.48% versus 1.09% (OR 0.55, 95% CI 0.37 to 0.82; p = 0.003). CONCLUSIONS: Based on all available evidence from randomized clinical trials or registries, clopidogrel, in addition to better tolerability and fewer side effects, is at least as efficacious as ticlopidine in reducing MACE. This finding may be due to the more rapid onset of an antiplatelet effect seen with the loading dose of clopidogrel, which was used in most of these studies, or to better patient compliance with clopidogrel therapy. Therefore, clopidogrel plus aspirin should replace ticlopidine plus aspirin as the standard antiplatelet regimen after stent deployment.

Aspirin↗
PubMed2002

Acute angiographic and clinical results of the NIR w/SOX stent.

Acute angiographic and clinical results of the NIR w/SOX stent (Boston Scientific/Scimed, Inc., Maple Grove, Minnesota) were evaluated. Between March 2000 and May 2000, a total of 102 lesions in 88 patients underwent stenting with the NIR w/SOX stent. The reference vessel diameter and lesion length were 2.97 +/- 0.50 mm and 16.2 +/- 6.5 mm, respectively. The minimal lumen diameter increased from 0.68 +/- 0.45 to 3.07 +/- 0.50 mm. Stent delivery failure was observed in 4 lesions (3.9%). On the other hand, the NIR w/SOX stent was successfully delivered in 7 of 9 lesions that had unsuccessful delivery of other kinds of stents. Angiographic success was observed in all except 1 lesion where the NIR w/SOX stents could not be delivered. There were no procedural myocardial infarctions or deaths. In one case, procedural coronary bypass surgery was performed. There was no acute closure or subacute stent thrombosis. Despite unfavorable lesion characteristics, the NIR w/SOX stent achieves high procedural success and acceptable stent delivery. Furthermore, it may have a high probability to be delivered in lesions where other kinds of stent result in unsuccessful delivery.

Aged↗
PubMed1998

Coronary stent implantation throughout technical evolution: immediate and follow-up results.

Coronary stenting (stent implantation) has evolved over the last 5 years with changes in stent design, stent material and the implantation technique. The use of high-pressure balloon inflation (HP), intravascular ultrasound (IVUS) and appropriate antiplatelet therapy have contributed to the abolishment of the need for subsequent anticoagulation, allowing extended stent applications. We compared results in three groups of patients having stent implantation throughout the period of evolution: group A: no IVUS, no HP, with subsequent anticoagulation treatment (n 3 434); group B: no IVUS, yes HP, without subsequent anticoagulation treatment (n 3 192); and group C: yes IVUS, yes HP, without subsequent anticoagulation treatment (n 3 588). The primary success rates were comparable in all groups. There was a clear change in indications for stenting in groups B and C compared with group A (elective stenting: group A 3 32%; group B 3 66%; group C 3 69%; P < 0.0001), in reference vessel size (group A 3 3.22 3 0.37 mm; group B 3 2.92 3 0.56 mm; group C 3 2.98 3 0.57 mm; P < 0.0001), and for presence of type B2 and C lesions (group A 3 57%; group B 3 72%; group C 3 74%; P < 0.001). The complication rate significantly decreased in group C (group A 3 3.6%; group B 3 4.1%; group C 3 1.2%; P < 0.001) and the mean patient hospital stay decreased to 2 days in groups B and C due to the abolition of the need for anticoagulant treatment. The angiographic restenosis rate increased in groups B and C (group A 3 20%; group B 3 34%; group C 3 32%; P < 0.001). The need for a repeat procedure increased as stenting of more complex lesions and smaller vessels was attempted: target lesion revascularization (TLR) was performed in 16% of patients in group A (73/434), in 18% of group B (35/192) and in 22% of group C (129/588) (P 3 0.04 for A versus C). Major cardiac events (MACE) occurred in 142 patients in group A (33%), 60 patients in group B (31%) and in 181 patients in group C (30%). The evolving technique of coronary stenting has expanded the spectrum of indications and range of coronary vessels attempted, and decreased the complication rates and hospital stay. However, in less-favorable subsets, additional improvements are needed to affect the long-term outcome.

Journal Article↗
PubMedDate not supplied

Influence of Class I interferons on performance of vascular cells on stent material in vitro.

PURPOSE: Numerous reports suggest that Class 1 interferons (IFNs), particularly IFN-gamma, inhibit migration and proliferation of different types of human cells. The objective of the present study was to determine the effect of Class I IFNs on viability and growth characteristics of human aortic endothelial cells (ECs), smooth muscle cells (SMC) and fibroblasts (FBs) in vitro. METHODS: Stainless-steel (316-l) disks were coated with fibrin meshwork containing IFN-gamma or IFN-alpha. The discs and IFN embedded meshwork were incubated with human EC, SMC and FB, and then cultured, whereas control cells were seeded onto uncoated surfaces or plain fibrin meshwork. Concentrations of recombinant IFN varied from 5 to 20 ng/cm(2). Assessment of effect on cell viability, growth and attachment was performed utilizing Alamar Blue (AB) assay. Cell morphology was assessed by scanning electron microscopy (SEM). RESULTS: We have now shown inhibitory capacity of IFN-gamma on all three types of unstimulated cells. The growth-inhibitory effect was maximal with SMC, while it was minimal with FB and EC. IFN-gamma abrogated mitogenic responses of SMC but not EC and partially FB to VEGF and FGF stimulation. IFN-alpha was able to inhibit EC growth and, to a lesser extent, FB, and did influence growth rates of SMC. Biochemical analysis of lactate dehydrogenase activity suggested that IFN was not toxic to vascular cells. We also measured the expression of cell adhesive molecules: P- and E-selections, PECAM and ICAM-1. These molecules were upregulated by IFN in EC. Media derived from quiescent human SMC displayed low immunoreactive elastase activity, while conditional media after IFN-gamma treatment but not IFN-alpha treatment had approximately a threefold greater activity. CONCLUSION: These data suggest that IFN-gamma significantly inhibits SMC growth in the absence of significant endothelial toxicity and is dose-dependent; however, animal experiments are needed to further explore the antirestenotic effects of IFNs.

Antineoplastic Agents↗