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1.
Pharmazie ; 79(3): 82-90, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38872268

ABSTRACT

Background and aim: Prescription patterns of antidepressants have changed over the years with a shift towards newer antidepressants with better tolerability and safety. Polypharmacy is common in psychiatry settings. The study aimed to evaluate the antidepressant drug prescription pattern and polypharmacy in a psychiatry outpatient setting. Investigations: This prospective observational study was conducted in a psychiatric outpatient clinic. The medication use data of eligible patients were collected. In addition, the rationale of antidepressant medication prescription, the defined daily dosage (DDD), the prescribed daily dose (PDD), and the PDD to DDD ratio were assessed. The assessment of prescription polypharmacy was conducted utilizing the framework provided by the National Association of State Mental Health Program Directors. Results: Data from 131 patients was analyzed. Major depressive disorder (32.8%) was the most common disorder for which antidepressants were prescribed. The majority, 91 (69.4%), received monotherapy. Selective serotonin reuptake inhibitors were the most frequently prescribed drugs in 69 (52.7%). Mirtazapine was the most frequently 32(24.4%) prescribed drug. Escitalopram and mirtazapine were the most commonly prescribed combination therapy (4.6%). Antipsychotic medications (37.4%) were the most widely co-prescribed medications, along with antidepressants. The PDD to DDD ratio was less than 1 for mirtazapine and imipramine; they were ≥1 for others. Psychiatric polypharmacy was documented in 87.1% of prescriptions. The total polypharmacy was not significantly (p>0.05) associated with demographic, illness, and treatment-related variables. Conclusion: Selective serotonin reuptake inhibitors were the most commonly prescribed antidepressants, monotherapy, and combination therapy. A substantial amount of patients received concomitant administration of antidepressants or psychotropic drugs, warranting careful monitoring.


Subject(s)
Antidepressive Agents , Outpatients , Polypharmacy , Practice Patterns, Physicians' , Humans , Antidepressive Agents/administration & dosage , Antidepressive Agents/therapeutic use , Male , Female , Prospective Studies , Cross-Sectional Studies , Practice Patterns, Physicians'/statistics & numerical data , Middle Aged , Adult , Mental Disorders/drug therapy , Drug Therapy, Combination , Drug Prescriptions/statistics & numerical data , Depressive Disorder, Major/drug therapy , Aged , Antipsychotic Agents/administration & dosage , Antipsychotic Agents/therapeutic use , Young Adult , Selective Serotonin Reuptake Inhibitors/administration & dosage , Selective Serotonin Reuptake Inhibitors/therapeutic use
2.
J Am Chem Soc ; 146(12): 7950-7955, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38483267

ABSTRACT

Single-site catalysts (SSCs) achieve a high catalytic performance through atomically dispersed active sites. A challenge facing the development of SSCs is aggregation of active catalytic species. Reducing the loading of these sites to very low levels is a common strategy to mitigate aggregation and sintering; however, this limits the tools that can be used to characterize the SSCs. Here we report a sintering-resistant SSC with high loading that is achieved by incorporating Anderson-Evans polyoxometalate clusters (POMs, MMo6O24, M = Rh/Pt) within NU-1000, a Zr-based metal-organic framework (MOF). The dual confinement provided by isolating the active site within the POM, then isolating the POMs within the MOF, facilitates the formation of isolated noble metal sites with low coordination numbers via exsolution from the POM during activation. The high loading (up to 3.2 wt %) that can be achieved without sintering allowed the local structure transformation in the POM cluster and the surrounding MOF to be evaluated using in situ X-ray scattering with pair distribution function (PDF) analysis. Notably, the Rh/Pt···Mo distance in the active catalyst is shorter than the M···M bond lengths in the respective bulk metals. Models of the active cluster structure were identified based on the PDF data with complementary computation and X-ray absorption spectroscopy analysis.

3.
Neoplasia ; 36: 100874, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36638586

ABSTRACT

Despite marked success in treatment with immune checkpoint inhibitor (CPI), only a third of patients are responsive. Thus, melanoma still has one of the highest prevalence and mortality rates; which has led to a search for novel combination therapies that might complement CPI. Aberrant methylomes are one of the mechanisms of resistance to CPI therapy. S-adenosylmethionine (SAM), methyl donor of important epigenetic processes, has significant anti-cancer effects in several malignancies; however, SAM's effect has never been extensively investigated in melanoma. We demonstrate that SAM modulates phenotype switching of melanoma cells and directs the cells towards differentiation indicated by increased melanogenesis (melanin and melanosome synthesis), melanocyte-like morphology, elevated Mitf and Mitf activators' expression, increased antigen expression, reduced proliferation, and reduced stemness genes' expression. Consistently, providing SAM orally, reduced tumor growth and progression, and metastasis of syngeneic BRAF mutant and wild-type (WT) melanoma mouse models. Of note, SAM and anti-PD-1 antibody combination treatment had enhanced anti-cancer efficacy compared to monotherapies, showed significant reduction in tumor growth and progression, and increased survival. Furthermore, SAM and anti-PD-1 antibody combination triggered significantly higher immune cell infiltration, higher CD8+ T cells infiltration and effector functions, and polyfunctionality of CD8+ T cells in YUMMER1.7 tumors. Therefore, SAM combined with CPI provides a novel therapeutic strategy against BRAF mutant and WT melanomas and provides potential to be translated into clinic.


Subject(s)
Immune Checkpoint Inhibitors , Melanoma , Animals , Mice , Immune Checkpoint Inhibitors/pharmacology , Immune Checkpoint Inhibitors/therapeutic use , Proto-Oncogene Proteins B-raf/genetics , S-Adenosylmethionine/pharmacology , S-Adenosylmethionine/therapeutic use , CD8-Positive T-Lymphocytes , Melanoma/drug therapy , Melanoma/genetics , Melanoma/pathology , Carcinogenesis , Cell Transformation, Neoplastic
4.
Inorg Chem ; 62(5): 1797-1803, 2023 Feb 06.
Article in English | MEDLINE | ID: mdl-35344660

ABSTRACT

Polyoxovanadate-alkoxide clusters are a new class of electroactive species with applications in a wide variety of fields from redox catalysis to energy storage. Heterometallic installation in these species can be used to modulate the redox properties of polyoxovanadate-alkoxide clusters and thus their applications. However, the formation mechanism of heterometallic polyoxovanadate alkoxides during the solvothermal process is unknown, limiting our understanding regarding what thermodynamic driving forces and/or kinetic barriers are present in the heterometal insertion. Here, we present a computational study on the nucleation pathways of the iron-functionalized mixed-valent hexameric [VV2VIV3O5(µ6-O)(µ2-OCH3)12(FeIIICl)] polyoxovanadate-alkoxide cluster.

5.
Eur Rev Med Pharmacol Sci ; 26(13): 4840-4845, 2022 07.
Article in English | MEDLINE | ID: mdl-35856376

ABSTRACT

OBJECTIVE: Although vancomycin is an effective antibiotic against methicillin-resistant Staphylococcus aureus, its usage is often associated with nephrotoxicity which necessitates optimization of the vancomycin dose to be both precise and appropriate. To achieve this, the importance of therapeutic drug monitoring arises, and serum trough vancomycin concentrations are the most accurate and practical method for monitoring vancomycin effectiveness and even risk of nephrotoxicity. This study evaluated the influences on the trough levels of vancomycin given to admitted patients at King Fahad Specialist Hospital (KFSH). PATIENTS AND METHODS: This cross-sectional hospital-based study has been conducted at KFSH among 197 patients, of which 53.3% were male and 46.7% were female. They received intravenous vancomycin at intermittent dose of 30 mg/kg/day with no clinical or laboratory renal impairment. The serum was drawn trough concentrations within 15 to 45 minutes before the fourth vancomycin dose. RESULTS: One-way ANOVA test showed a significantly higher trough level of vancomycin among females, patients older than 50 years, and CCU and CSICU admitted patients (p-value < 0.05). Spearman correlation test also showed significant correlation with the serum vancomycin trough levels, site of infection (Rho=0.406, p=0.009), age (Rho=0.341, p=0.044) and patients' admission (Rho=0.321, p=0.041). CONCLUSIONS: Even at body adjusted dosing, vancomycin serum trough levels varied among patients with significant variations of age, gender, site of infection and type of admission, especially CCU and CSICU, which raises the concept of dose individualization, age and gender considerations especially among critically ill patients.


Subject(s)
Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Anti-Bacterial Agents/therapeutic use , Cross-Sectional Studies , Female , Hospitals , Humans , Male , Retrospective Studies , Staphylococcal Infections/drug therapy , Vancomycin
6.
Inorg Chem ; 60(10): 7262-7268, 2021 May 17.
Article in English | MEDLINE | ID: mdl-33891406

ABSTRACT

The synthesis of novel tunable electroactive species remains a key challenge for a wide range of chemical applications such as redox catalysis, energy storage, and optoelectronics. In recent years, polyoxovanadate (POV) alkoxide clusters have emerged as a new class of compounds with highly promising electrochemical applications. However, our knowledge of the formation pathways of POV alkoxides is rather limited. Understanding the speciation of POV alkoxides is fundamental for controlling and manipulating the evolution of transient species during their nucleation and therefore tuning the properties of the final product. Here, we present a computational study of the nucleation pathways of a mixed-valent [(VV6-nVIVnO6)(O)(O-CH3)12](4-n)+ POV alkoxide cluster in the absence of reducing agents other than methanol.

7.
Nanoscale ; 13(12): 6162-6173, 2021 Mar 28.
Article in English | MEDLINE | ID: mdl-33734254

ABSTRACT

We report a rare example of the direct alkylation of the surface of a plenary polyoxometalate cluster by leveraging the increased nucleophilicity of vanadium oxide assemblies. Addition of methyl trifluoromethylsulfonate (MeOTf) to the parent polyoxovanadate cluster, [V6O13(TRIOLR)2]2- (TRIOL = tris(hydroxymethyl)methane; R = Me, NO2) results in functionalisation of one or two bridging oxide ligands of the cluster core to generate [V6O12(OMe)(TRIOLR)2]1- and [V6O11(OMe)2(TRIOLR)2]2-, respectively. Comparison of the electronic absorption spectra of the functionalised and unfunctionalised derivatives indicates the decreased overall charge of the complex results in a decrease in the energy required for ligand to metal charge transfer events to occur, while simultaneously mitigating the inductive effects imposed by the capping TRIOL ligand. Electrochemical analysis of the family of organofunctionalised polyoxovanadate clusters reveals the relationship of ligand environment and the redox properties of the cluster core: increased organofunctionalisation of the surface of the vanadium oxide assembly translates to anodic shifts in the reduction events of the Lindqvist ion. Overall, this work provides insight into the electronic effects induced upon atomically precise modifications to the surface structure of nanoscopic, redox-active metal oxide assemblies.

8.
Int J Surg ; 13: 76-79, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25479146

ABSTRACT

INTRODUCTION: This study was aimed to assess the outcome of Ilioinguinal, Iliohypogastric block and wound infiltration with 0.75% ropivacaine on pain perception, first analgesic request and hospital stay following inguinal Lichtenstein mesh repair. METHOD: This was a prospective, randomized, double-blind study with 60 patients undergoing inguinal hernioplasty under general anesthesia. Patients were randomly allocated to one of the two groups by the sealed envelope method. Group 1 (n=30) received nerve blocks and incision infiltration with 0.75% ropivacaine while group 2 (n=30) received isotonic saline. Postoperatively pain intensity, time of demand for the first analgesic and duration of hospital stay were assessed. RESULTS: Median Visual Analog Scale (VAS) score of group 1 was 4 (high=6, low=3) while for group 2 was 5.50 (high=8, low=4) and the p value was <0.001. Mean time for the demand of the first analgesic was prolonged from 1.19±1.05 h to 5.31±1.14 h with the p value of <0.0005, while the mean time of hospital stay was reduced from 22.5±3.30 h to 14.1±2.99 h with the p value of <0.0005. CONCLUSION: Preemptive analgesia with 0.75% ropivacaine causes significant reduction in pain perception, request for an analgesic and hospital stay. Therefore it is advisable before inguinal hernioplasty.


Subject(s)
Amides , Anesthetics, Local , Hernia, Inguinal/surgery , Herniorrhaphy/methods , Nerve Block/methods , Pain, Postoperative/prevention & control , Adult , Aged , Double-Blind Method , Female , Groin/surgery , Humans , Length of Stay/statistics & numerical data , Male , Middle Aged , Pain Perception/drug effects , Pain, Postoperative/drug therapy , Prospective Studies , Ropivacaine , Surgical Mesh , Visual Analog Scale
10.
IET Nanobiotechnol ; 6(4): 129-35, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23101866

ABSTRACT

Chitosan-poly(vinyl alcohol) (Cs:PVA) nanofibrous scaffolds were electrospun from 2:3 (wt/wt) Cs:PVA solution dissolved in 80% acetic acid. In vivo study was carried out on the dorsum skin of rat which burnt with a hot brass cylinder. The scaffolds were applied in two forms, that is, acellular (n=6) and cell-seeded with mesenchymal stem cells (n=6). Macroscopic measurements of wound area showed good aspect healing effect of scaffolds in comparison with control wounds specially in 15 days post operating. Pathological studies were done on the wounds to investigate the healing effects. The healing process of the wound covered with Cs/PVA nanofibrous scaffolds was much rapid compared to untreated wounds. However, the presence of stem cells on this scaffolds accelerated the wound healing process owing to their ability of collagen regeneration.


Subject(s)
Burns/therapy , Chitosan/chemistry , Nanostructures/chemistry , Skin/injuries , Stem Cell Transplantation/instrumentation , Tissue Engineering/instrumentation , Tissue Scaffolds , Animals , Bandages , Burns/pathology , Chitosan/therapeutic use , Dermatologic Surgical Procedures/methods , Equipment Design , Equipment Failure Analysis , Male , Nanostructures/therapeutic use , Polyvinyl Alcohol/chemistry , Polyvinyl Alcohol/therapeutic use , Rats , Rats, Sprague-Dawley , Skin/pathology , Treatment Outcome
11.
IET Nanobiotechnol ; 4(4): 109 -17, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20887083

ABSTRACT

Chitosan-polyvinyl alcohol (PVA) blend nanofibrous webs were fabricated in different blend ratios through electrospinning procedures. From scanning electron microscopy (SEM) results, 25/75 blend ratio of chitosan-PVA was selected for biological studies. In vivo studies were carried out on the dorsum of rats of two types: longitudinal incisional wounds (n=8 rats) and round excisional wounds (n=8). Pathological study was done on the wounds to investigate the healing process. The histological study in wound healing indicated that the administration of chitosan nanofibrous web improved the wound healing, qualitatively and quantitatively.


Subject(s)
Bandages , Chitosan/therapeutic use , Nanostructures/therapeutic use , Polyvinyl Alcohol/therapeutic use , Wound Healing/physiology , Wounds, Penetrating/pathology , Wounds, Penetrating/therapy , Animals , Biocompatible Materials/therapeutic use , Male , Materials Testing , Rats , Rats, Sprague-Dawley , Treatment Outcome
12.
Magn Reson Chem ; 48(9): 704-11, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20641133

ABSTRACT

This article describes a solid-state NMR (SSNMR) investigation of the influence of hydration and chemical cross-linking on the molecular dynamics of the constituents of the bovine pericardium (BP) tissues and its relation to the mechanical properties of the tissue. Samples of natural phenethylamine-diepoxide (DE)- and glutaraldehyde (GL)-fixed BP were investigated by (13)C cross-polarization SSNMR to probe the dynamics of the collagen, and the results were correlated to the mechanical properties of the tissues, probed by dynamical mechanical analysis. For samples of natural BP, the NMR results show that the higher the hydration level the more pronounced the molecular dynamics of the collagen backbone and sidechains, decreasing the tissue's elastic modulus. In contrast, in DE- and GL-treated samples, the collagen molecules are more rigid, and the hydration seems to be less effective in increasing the collagen molecular dynamics and reducing the mechanical strength of the samples. This is mostly attributed to the presence of cross-links between the collagen plates, which renders the collagen mobility less dependent on the water absorption in chemically treated samples.


Subject(s)
Collagen/chemistry , Molecular Dynamics Simulation , Pericardium/chemistry , Animals , Carbon Isotopes , Cattle , Magnetic Resonance Spectroscopy/standards , Molecular Structure , Reference Standards
13.
Chem Phys Lipids ; 163(6): 545-51, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20347728

ABSTRACT

In this work we report on a study of the morphological changes of LDL induced in vitro by metallic ions (Cu(2+) and Fe(3+)). These modifications were characterized by transmission electron microscopy, nuclear magnetic resonance and the Z-scan technique. The degree of oxidative modification of LDL was determined by the TBARS and lipid hydroperoxides assays. It is shown that distinct pathways for modifying lipoproteins lead to different morphological transformations of the particles characterized by changes in size and/or shape of the resulting particles, and by the tendency to induce aggregation of the particles. There were no evidence of melting of particles promoted by oxidative processes with Cu and Fe.


Subject(s)
Copper/chemistry , Iron/chemistry , Lipoproteins, LDL/chemistry , Cations/chemistry , Magnetic Resonance Spectroscopy , Microscopy, Electron, Transmission , Oxidation-Reduction , Thiobarbituric Acid Reactive Substances/chemistry
14.
Chemistry and Physics of Lipids ; 163(6): 545-551, 2010.
Article in English | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP, SESSP-IBACERVO | ID: biblio-1061937

ABSTRACT

In this work we report on a study of the morphological changes of LDL induced in vitro by metallic ions (Cu2+ and Fe3+). These modifications were characterized by transmission electron microscopy, nuclear magnetic resonance and the Z-scan technique. The degree of oxidative modification of LDL was determined by the TBARS and lipid hydroperoxides assays. It is shown that distinct pathways for modifying lipoproteins lead to different morphological transformations of the particles characterized by changes in size and/or shape of the resulting particles, and by the tendency to induce aggregation of the particles. There were no evidence of melting of particles promoted by oxidative processes with Cu and Fe.


Subject(s)
Male , Female , Humans , Lipoproteins
15.
J. venom. anim. toxins incl. trop. dis ; 16(1): 46-59, 2010. ilus, tab
Article in English | LILACS, VETINDEX | ID: lil-542428

ABSTRACT

Scorpion envenomation is a life-threatening condition, especially in children and elderly individuals affected by respiratory and cardiovascular diseases. In this study, the toxic effects of median lethal dose (LD50) injections of Mesobuthus eupeus (Me) venom on the heart and lungs of anesthetized rabbits were investigated. Six rabbits were selected and alterations in their electrocardiogram, heart rate, respiration and blood pressure before and after venom injection were recorded. Cardiac troponin T (cTnT), creatinine kinase muscle-brain fraction (CK-MB) and lactate dehydrogenase (LDH) were measured at 0, 1 and 3 hours after envenomation and pathology studies were carried out postmortem. All the animals showed signs and symptoms of envenomation within 40 minutes and died 3 to 3.5 hours after venom injection. Pathology studies revealed alveolar edema in 100 percent of the rabbits and myocardial infarction in 16 percent. The main histopathological changes were myocytolysis, coagulation necrosis, focal hemorrhage, thrombus formation both in myocardium and on endocardial surfaces as well as inflammatory infiltrates in the heart and hemorrhage, vascular thrombus and interstitial inflammation in the lungs. ECG monitoring of rabbits showed ST elevation, ST depression and inverted T and Q waves. In addition, although cTnT levels increased in 16 percent of the animals and serum LDH was also augmented, none of these changes was statistically significant. The enzyme CK-MB also did not show any change after Me venom injection. In conclusion, the results of this study showed that Me venom killed animals in less than 3.5 hours through severe pulmonary damage and it appears that the deaths could not be attributed to cardiovascular lesions. Therefore, Me venom effects on the lungs are so important that they appear to be independent of heart damage.(AU)


Subject(s)
Animals , Phosphotransferases , Scorpion Venoms , Cardiovascular Diseases , Troponin T , Scorpion Stings , L-Lactate Dehydrogenase , Lethal Dose 50
16.
Int Urol Nephrol ; 39(3): 955-8, 2007.
Article in English | MEDLINE | ID: mdl-16835724

ABSTRACT

Unilateral renal cystic disease (URCD) is a rare condition, with pathological features indistinguishable from autosomal dominant polycystic kidney disease (ADPKD). In contrast to this condition, however, URCD is not inherited, is not associated with progressive deterioration in renal function, and is unilateral. We present a case of URCD associated with polycythaemia, which showed resolution following nephrectomy. Secondary polycythaemia has not previously been reported in cases of URCD, but may be hypothesised to be a result of excess erythropoietin production.


Subject(s)
Kidney Diseases, Cystic/complications , Polycythemia/etiology , Erythropoietin/blood , Humans , Kidney Diseases, Cystic/surgery , Male , Middle Aged , Nephrectomy , Polycythemia/blood
17.
Endocrinology ; 146(7): 2885-94, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15831570

ABSTRACT

We evaluated the capacity of estradiol (E(2)) to regulate PTHrP production, cell growth, tumor growth, and metastasis to the skeleton in breast cancer. In estrogen receptor (ER)-negative human breast cancer cells, MDA-MB-231, and cells transfected with full-length cDNA encoding ER (S-30), E(2) caused a marked decrease in cell growth and PTHrP production, effects that were abrogated by anti-E(2) tamoxifen. E(2) also inhibited PTHrP promoter activity in S-30 cells. For in vivo studies, MDA-MB-231 and S-30 cells were inoculated into the mammary fat pad of female BALB/c nu.nu mice. Animals receiving S-30 cells developed tumors of significantly smaller volume compared with MDA-MB-231 tumor-bearing animals. This change in tumor volume was reversed when S-30 cells were inoculated into ovariectomized (OVX) hosts. Inoculation of MDA-MB-231 cells into the left ventricle resulted in the development of lesions in femora and tibia as determined by x-ray analysis. In contrast, these lesions were significantly smaller in volume and number in animals inoculated with S-30, and this lower incidence was reversed in OVX animals. Bone histological analysis showed that the tumor volume to tissue volume ratio was comparable with that seen by x-ray. Immunohistochemical analysis showed that PTHrP production was inhibited in S-30 group and restored to levels comparable to that seen in MDA-MB-231 tumor-bearing animals when S-30 cells were inoculated in OVX animals. Collectively these studies show that E(2) production is inversely correlated with PTHrP production and that the growth-promoting effect of PTHrP has a direct impact on tumor growth at both nonskeletal and skeletal sites.


Subject(s)
Bone Neoplasms/secondary , Breast Neoplasms/pathology , Breast Neoplasms/secondary , Estradiol/pharmacology , Parathyroid Hormone-Related Protein/biosynthesis , Animals , Bone Neoplasms/diagnostic imaging , Bone Neoplasms/pathology , Breast Neoplasms/metabolism , Cell Division/drug effects , Cell Line, Tumor , Estrogen Receptor alpha/genetics , Estrogen Receptor alpha/metabolism , Female , Gene Silencing , Humans , Immunohistochemistry , Mice , Mice, Inbred BALB C , Neoplasm Transplantation , Ovariectomy , Radiography , Transfection , Transplantation, Heterologous
18.
Br J Plast Surg ; 58(1): 58-64, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15629168

ABSTRACT

Opioid receptors have been implicated in protecting several organ systems from ischaemic events. The authors have studied the effects of opioid receptors on random-pattern skin flap survival. Sixty-nine male Sprague-Dawley rats were used. Bipedicled dorsal skin flaps (2 x 8 cm) were elevated at the midline. Different doses of morphine (0.01, 0.1, 1 and 5 mg/flap) were administered locally in the cranial half of the flap and systemically through intraperitoneal injections (5 and 10 mg/kg). In another experiment, 0.4 mg/flap of naloxone was injected followed by 5 mg/flap injection of morphine to determine whether the effect of morphine is receptor mediated. The role of the opioid receptors in the ischaemic preconditioning (IPC) phenomenon was investigated by administration of naloxone (0.4 mg/flap) 1 h before clamping the cranial pedicle for 20 min followed by 40 min of reperfusion. Appropriate control groups were included. The cranial pedicle was cut 2 h after saline or drug administration in all groups and flap survival area was evaluated on the seventh postoperative day. Local administration of morphine in higher doses (1 and 5 mg/flap) significantly reduced the amount of flap necrosis when compared to that of the control cohort (P < 0.05). Naloxone abolished this protective effect of morphine. Furthermore naloxone significantly decreased the anti-ischaemic effect of the IPC. Systemic administrations of morphine had no significant effect on flap survival area in compare with the control group.


Subject(s)
Receptors, Opioid/physiology , Surgical Flaps/physiology , Animals , Dose-Response Relationship, Drug , Injections, Intraperitoneal , Ischemia/prevention & control , Male , Morphine/administration & dosage , Naloxone/administration & dosage , Narcotic Antagonists/administration & dosage , Narcotics/administration & dosage , Necrosis , Rats , Rats, Sprague-Dawley , Skin , Surgical Flaps/blood supply , Surgical Flaps/pathology , Tissue Survival/drug effects , Tissue Survival/physiology
19.
Int J Artif Organs ; 27(8): 691-8, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15478540

ABSTRACT

Attempts have been made in this study to prepare a homogeneous and stable coating of graphite on polyester vascular grafts (GPVG) using an electrophoresis method to evaluate thromboresistant and blood compatibility of GPVG in comparison to non-coated PVG and InterGard (collagen sealed PVG) as control. Lactate dehydrogenase (LDH) activity measurement was carried out on all PVG types to evaluate platelet adhesion. To examine tissue reaction GPVG and non-coated sheets of knitted polyester fabric were implanted simultaneously in the dorsal flank of rats subcutaneously. The GPVG, non-coated and control were implanted in descending aorta as end-to-end or end-to-side implantation substitution in 25 sheep for 4-60 weeks. Results showed that the graphite coating on polyester vascular grafts reduced the number of adherent platelets and prevent platelet activation and spreading on the surface in comparison with non-coated and control. Pathological investigation showed inflammatory reactions were totally resolved after 12 weeks and there was no difference in the tissue reaction between graphite coated, non-coated and control patches. All grafts remained patent and there was no significant difference in patency rate between these three types of PVG. We found that GPVG has no need for pre-clotting and it showed lower platelet aggregation, thinner capsule formation and lower calcification after 15 months. However, suturing of GPVG was more difficult in comparison with the other types.


Subject(s)
Blood Vessel Prosthesis , Coated Materials, Biocompatible/chemistry , Graphite , Polyesters , Animals , Aorta, Thoracic/pathology , Aorta, Thoracic/surgery , Blood Platelets/cytology , Calcinosis/pathology , Female , Fibrosis , In Vitro Techniques , L-Lactate Dehydrogenase/metabolism , Platelet Activation , Platelet Adhesiveness , Rats , Sheep
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