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1.
Mar Pollut Bull ; 205: 116675, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38972221

RESUMO

The concentrations, spatial distributions, pollution level, and health risks of heavy metals in sediments of the Sharm Obhur, Northern Jeddah, Saudi Arabia were evaluated. Average concentrations were found to be: Cr > Zn > Ni > Cu > As>Pb with the highest concentrations found near the head of the sharm, and decreasing towards the mouth. Environmental indices, together with the statistical analyses, showed that the sharm experiences a low to moderate degree of pollution. Sampling sites with heavy metal contamination are concentrated near the head and the southern coast of the sharm, where intensive human activities associated with a boat dock, construction, and recreation are common. The mean carcinogenic risk (CR) values of As, Cr and Ni are at permissible level suggesting unlikely adverse impacts of heavy metals on human health. Despite acceptable CR values; however, serious non-carcinogenic and carcinogenic health threats from metals may yet be an issue particularly for sensitive populations such as children.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados , Poluentes Químicos da Água , Arábia Saudita , Metais Pesados/análise , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , Humanos , Medição de Risco
2.
Sci Rep ; 14(1): 15887, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987272

RESUMO

The deposition of paraffin on pipelines during crude oil transit and low-temperature restart processes poses a significant challenge for the oil industry. Addressing this issue necessitates the exploration of innovative materials and methods. Pour point depressants (PPDs) emerge as crucial processing aids to modify paraffin crystallization and enhance crude oil flow. This study focuses on the combustion of polyethylene terephthalate (PET) waste, a prevalent plastic, in two distinct oils (castor and jatropha). The resulting black waxy substances (PET/Castor and PET/Jatropha) were introduced in varying weights (1000, 2000, and 3000 ppm) to crude oil. The PET/castor oil combination demonstrated a remarkable reduction in pour point from 18 to -21 °C at 3000 ppm concentration, significantly more effective than PET/jatropha blends. Substantial decreases in viscosity (up to 75%) and shear stress (up to 72%) were also observed for both blends, most prominently at lower temperatures near the pour point. The synergistic effect of PET and oils as nucleating agents that alter crystallization patterns and restrict crystal growth contributes to this enhanced low-temperature flow. This highlights the potential of PET plastic waste as an economical, abundant, and eco-friendly additive to develop high-performance PPDs for crude oil.

3.
PLoS One ; 19(6): e0303981, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38848399

RESUMO

Nanofluids have a wide range of applications due to their unique properties, such as enhanced thermal conductivity, convective heat transfer, and mass transfer. These applications can be seen in heat exchangers, cooling systems, and electronic devices to improve thermal performance. To enhance the cooling efficiency and lifespan of electronic devices such as smartphones, televisions, and computers nanofluids are used. These novel types of fluids can be used in energy storage systems, cancer treatment, imaging, and drug deliveryKeeping in mind, the real-time applications in engineering, industry, and science, the current study is carried out. In the present study for heat and mass transportation, the two-phase Buongiorno model for nanofluid is employed to scrutinize Brownian motion and thermophoresis aspects using stationary sphere and plume region. The temperature-dependent viscosity and thermal conductivity effects are encountered in momentum and energy equations, respectively are encountered. The proposed mechanism in the partial differential equations having dimensional form is converted to a non-dimensional form using appropriate dimensionless variables. The solution of the current non-linear and coupled model is obtained using the finite difference method. The numerical solutions presented in graphs and tables indicate that along with heat and mass transfer phenomena are entirely dependent on thermophoresis, Brownian motion, temperature-dependent viscosity, and thermal conductivity. The results indicate that the quantitative behavior of the velocity field is enhanced by increasing values of thermal conductivity variation parameters for both the sphere and the plume region at each position. On the other hand, the reverse trend is noted against the rising magnitudes of the viscosity variation parameter, thermophoresis parameter, and Brownian diffusion parameter. Additionally, the temperature in the plume region declines to enhance thermal conductivity variation parameter. A test for grid independence was performed by considering various grid points. Excellent solution accuracy has been seen as the number of grid points has risen. This ensures the validity and accuracy of the currently employed method. The current results are compared with already published solutions for the validation of the current model for specific cases. It has been noted that there is excellent agreement between both of the results. This close agreement between the results indicates the validation of the current solutions.


Assuntos
Modelos Teóricos , Condutividade Térmica , Viscosidade , Temperatura Alta , Temperatura
4.
J Vasc Surg Venous Lymphat Disord ; 12(3): 101859, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38447878

RESUMO

BACKGROUND: The optimal treatment approach for patients with active venous leg ulcers (VLUs) and post-thrombotic syndrome (PTS) associated with great saphenous vein (GSV) reflux remains unclear. To address this gap, we retrospectively compared the outcomes of patients with post-thrombotic VLU with an intact GSV vs those with a stripped or ablated GSV. METHODS: We retrospectively analyzed data from 48 patients with active VLUs and documented PTS, who were treated at a single center between January 2018 and December 2022. Clinical information, including ulcer photographs, was recorded in a prospectively maintained digital database at the initial and follow-up visits. Two patient groups-group A (with an intact GSV) and group B (with a stripped or ablated GSV)-were compared in terms of time to complete healing, proportion of ulcers achieving complete healing, and ulcer recurrence during the follow-up period. RESULTS: There were no significant differences in age, gender, initial ulcer size, or ulcer duration between the two groups. All included patients had femoropopliteal post-thrombotic changes. Group A had significantly more completely healed ulcers (33 of 34 ulcers, 97%) compared with group B (10 of 14 ulcers, 71%) (P = .008). Group A also exhibited a significantly shorter time to complete ulcer healing (median: 42.5 days, interquartile range [IQR]: 65) compared with group B (median: 161 days, IQR: 530.5) (P = .0177), with a greater probability of ulcer healing (P = .0084). Long-term follow-up data were available for 45 of 48 patients (93.7%), with a mean duration of 39.6 months (range: 5.7-67.4 months). The proportion of ulcers that failed to heal or recurred during the follow-up period was significantly lower in group A (9 of 32 ulcers, 27%) compared with group B (11 of 13 ulcers, 85%) (P = .0009). In addition, in a subgroup analysis, patients with an intact but refluxing GSV (12 of 34) had a significantly shorter time to heal (median: 34 days, IQR: 57.25) (P = .0242), with a greater probability of ulcer healing (P = .0091) and significantly fewer recurrences (2 of 12, 16%) (P = .006) compared with group B. CONCLUSIONS: Our findings suggest that removal of the GSV through stripping or ablation in patients with post-thrombotic deep venous systems affecting the femoropopliteal segment may result in delayed ulcer healing and increased ulcer recurrence. Patients with an intact GSV had better outcomes, even when the refluxing GSV was left untreated. These findings emphasize the potential impact of GSV treatment on the management of VLUs in individuals with PTS. Further investigation is needed to validate these results and explore alternative therapeutic strategies to optimize outcomes for this patient population.


Assuntos
Síndrome Pós-Trombótica , Úlcera Varicosa , Insuficiência Venosa , Humanos , Úlcera , Estudos Retrospectivos , Veia Safena/cirurgia , Resultado do Tratamento , Úlcera Varicosa/terapia , Insuficiência Venosa/cirurgia , Recidiva
5.
J Enzyme Inhib Med Chem ; 38(1): 2198163, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37036011

RESUMO

Novel series of aminopyrimidines bearing a biologically active cyclohexenone 3a-f and oxo-selaneylidene moiety 4, besides selenadiazolopyrimidines (5a-e and 7), were synthesised using 5,6-diaminouracils as starting materials. Compound 3a exhibited strong anti-proliferative activity against three cell lines: HepG-2 (IC50 14.31 ± 0.83 µM), A-549 (IC50 30.74 ± 0.76 µM), and MCF-7 (IC50 27.14 ± 1.91 µM). Also, it was four times more selectively cytotoxic against WI-38 cell lines than doxorubicin. Furthermore, Topoisomerase II (IC50 4.48 ± 0.65 µM) and HSP90 (IC50 1.78 ± 0.11 µM) were both strongly inhibited in vitro by 3a. The cell cycle was halted at the G1-S phase, and total apoptotic cells were 65 times more than control Hep-G2 cells. Besides, it increased caspase-3 gene expression, triggering mitochondrial cell death. Molecular docking study indicated that it could bind to Topoisomerase II and HSP90 binding sites in an inhibitory mode. Its geometric properties were investigated using the density functional theory (DFT). Furthermore, compound 3a demonstrated in silico good oral bioavailability.


Assuntos
Antineoplásicos , Proteínas de Choque Térmico HSP90 , Pirimidinas , Inibidores da Topoisomerase II , Pirimidinas/síntese química , Pirimidinas/farmacologia , Inibidores da Topoisomerase II/síntese química , Inibidores da Topoisomerase II/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Células Hep G2 , Células A549 , Células MCF-7 , Humanos , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Simulação por Computador , Antineoplásicos/síntese química , Antineoplásicos/farmacologia
6.
J Synchrotron Radiat ; 29(Pt 3): 765-774, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35511009

RESUMO

Synchrotron radiation-based techniques [X-ray absorption near-edge structure (XANES) and X-ray fluorescence (XRF)] combined with inductively coupled plasma-mass spectrometry (ICP-MS) were used for the assessment of heavy metals concentrations as well as lead (Pb) and nickel (Ni) speciation in airborne particulate matter (PM10) over two residential sites in Greater Cairo. Nineteen 24 h high-volume samples collected at Giza (G) Square and Helwan (H) University (Egypt) were selected for this study. Mean concentrations of heavy metals in PM10 at both sites were found to have the same descending order of Pb > Cu > Ni > Cd > Co > As, of which concentrations of Pb, Cu, Ni and Cd in H samples were higher than those in G samples. For Pb, synchrotron-based XRF results were in good agreement with concentrations obtained by ICP-MS. The XANES spectra of PM10 at the Pb L2-edge and Ni K-edge were compared with those of Pb and Ni in model standard compounds to provide information on the potential oxidation states as well as the chemical forms of those elements. The data show that Pb has similar chemical environments in both series G and H with the predominance of Pb2+ oxidation state. Nickel was found as Ni(OH)2, NiO and Ni metal in the analyzed samples. However, the content of Ni in the background filter shows a very strong interference with that of the collected PM10. Carcinogenic and non-carcinogenic risks resulting from the inhalation of the studied heavy metals were assessed for children and adult residents and were found below the safe limits, at both sites.


Assuntos
Metais Pesados , Material Particulado , Adulto , Cádmio/análise , Criança , Monitoramento Ambiental , Humanos , Chumbo/análise , Metais Pesados/análise , Níquel/análise , Material Particulado/análise , Medição de Risco , Síncrotrons
7.
Materials (Basel) ; 14(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443191

RESUMO

Radiation leakage is a serious problem in various technological applications. In this paper, radiation shielding characteristics of some natural rocks are elucidated. Mass attenuation coefficients (µ/ρ) of these rocks are obtained at different photon energies with the help of the EPICS2017 library. The obtained µ/ρ values are confirmed via the theoretical XCOM program by determining the correlation factor and relative deviation between both of these methods. Then, effective atomic number (Zeff), absorption length (MFP), and half value layer (HVL) are evaluated by applying the µ/ρ values. The maximum µ/ρ values of the natural rocks were observed at 0.37 MeV. At this energy, the Zeff values of the natural rocks were 16.23, 16.97, 17.28, 10.43, and 16.65 for olivine basalt, jet black granite, limestone, sandstone, and dolerite, respectively. It is noted that the radiation shielding features of the selected natural rocks are higher than that of conventional concrete and comparable with those of commercial glasses. Therefore, the present rocks can be used in various radiation shielding applications, and they have many advantages for being clean and low-cost products. In addition, we found that the EPICS2017 library is useful in determining the radiation shielding parameters for the rocks and may be used for further calculations for other rocks and construction building materials.

8.
Br J Oral Maxillofac Surg ; 59(6): 661-664, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34053800

RESUMO

Monitoring of microvascular free flaps is an influencing factor in the success or failure of the treatment. In this study, we aim to compare the accuracy of implantable Doppler and scintigraphy in the monitoring of a vascularised buried fibular graft for reconstruction of the mandible. In a prospective cohort study, an implantable Doppler was placed intraoperatively, and Single Photon Emission Computed Tomography (SPECT) was taken in patients when abnormal blood flow was detected via the implantable Doppler or 48 hours after operations in patients with normal signals on the Doppler. The flaps were explored if patients did not have regular signals via implantable Doppler or if SPECT revealed impaired perfusion. The number of true- and false-positive cases and true- and false-negative cases were documented. Positive predictive value (PPV) and negative predictive value (NPV) were calculated. Eighteen (29%) of 62 patients underwent explorative surgery. The sensitivity of SPECT was 38.88%, and specificity was 97.72%. In SPECT, PPV was 87.50% and NPV 79.62%. The sensitivity of the implantable Doppler was 72.22%, and specificity was 93.08%. In assessment with the implantable Doppler, PPV was 81.25% and NPV 93.18%. It seems that SPECT and the implantable Doppler had sufficient specificity in the monitoring of a buried fibular graft. However, SPECT had a lower sensitivity than the implantable Doppler.


Assuntos
Implantes Dentários , Retalhos de Tecido Biológico , Humanos , Mandíbula/diagnóstico por imagem , Mandíbula/cirurgia , Monitorização Fisiológica , Estudos Prospectivos , Tomografia Computadorizada de Emissão de Fóton Único
9.
Reprod Domest Anim ; 53(2): 319-325, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29134689

RESUMO

This study aimed to evaluate the effectiveness of hormonal treatments on ovarian activity and reproductive performance in Barki and Rahmani ewes during non-breeding season. Forty-eight multiparous ewes, 24 Barki and 24 Rahmani ewes were divided into two groups, 12 lactating and 12 dry ewes for each breed. Controlled internal drug release (CIDR) device was inserted in all ewes for 14 days in conjunction with intramuscular 500 IU equine chronic gonadotrophin (eCG) at day of CIDR removal. Data were analysed using PROC MIXED of SAS for repeated measures. Breed, physiological status and days were used as fixed effects and individual ewes as random effects. Barki ewes recorded higher (p < .05) total number of follicles, number of large follicles, serum estradiol concentration and estradiol: progesterone (E2 :P4 ) ratio compared to Rahmani ewes. Lactating ewes recorded higher (p < .05) number of small follicles and lower concentration of total antioxidant capacity (TAC) compared to dry ewes. Number and diameter of large follicles recorded the highest (p < .05) values accompanied with disappearance of corpora lutea at day of mating. Serum progesterone concentration recorded lower (p < .05) value at day of mating and the highest (p < .05) value at day 35 after mating. CIDR-eCG protocol induced 100% oestrous behaviour in both breeds, but Rahmani ewes recorded longer (p < .05) oestrous duration compared to Barki. Conception failure was higher (p < .05) in Barki compared to Rahmani ewes. In conclusion, CIDR-eCG protocol was more potent in improving ovarian activity in Barki compared to Rahmani ewes, but this protocol seems to induce hormonal imbalance in Barki ewes that resulted in increasing conception failure compared to Rahmani ewes.


Assuntos
Anestro/efeitos dos fármacos , Gonadotropinas Equinas/farmacologia , Progesterona/farmacologia , Ovinos , Administração Intravaginal , Animais , Cruzamento , Preparações de Ação Retardada , Implantes de Medicamento , Estradiol/sangue , Feminino , Gonadotropinas Equinas/administração & dosagem , Lactação , Folículo Ovariano/efeitos dos fármacos , Progesterona/administração & dosagem , Progesterona/sangue
10.
J Dairy Sci ; 100(6): 5028-5039, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28390723

RESUMO

The objective of this study was to compare the efficiency of hormonal treatments on ovarian activity and reproductive performance in anestrous Anglo-Nubian does during the nonbreeding season (February to May). A total of 48 multiparous does were divided into 2 groups (24 lactating does and 24 dry does). In each group, animals were allocated randomly into 2 equal subgroups (12 does each). In the first subgroup, does received a single 18-mg melatonin implant for 42 d followed by a controlled internal drug release (CIDR) device for 19 d in conjunction with 500 IU of equine chorionic gonadotropin (eCG) i.m. on the day of CIDR device removal. The second subgroup received CIDR combined with eCG in parallel with the first subgroup. Melatonin implantation induced a luteotrophic effect, expressed as an increasing number of corpora lutea, increased serum progesterone concentration, and reduced estradiol concentration. Regardless of treatment, dry does showed greater value of progesterone concentration. With the advancement of day of treatment, number of total follicles, small follicles, and medium follicles tended to increase to the greatest values at the day of CIDR device insertion. Furthermore, at day of mating, the numbers of large follicles reached the greatest value, which was associated with the lowest value of the number of corpora lutea. At day of mating, serum progesterone concentration achieved the lowest value, which increased until d 56 of pregnancy. The estradiol:progesterone ratio showed the opposite trend. The detrimental effect of reproductive seasonality, expressed as cessation of estrus behavior and fertile mating during the nonbreeding season, was successfully alleviated by the CIDR-eCG protocol. Furthermore, melatonin implantation in conjunction with the CIDR-eCG protocol enhanced conception rate and fecundity at d 28 of pregnancy and prolificacy at d 56 of pregnancy compared with does that were not implanted. Interestingly, does that failed to conceive did not come to heat again. In conclusion, the beneficial effect of melatonin implantation in conjunction with the CIDR-eCG protocol on the luteotrophic effect was reflected in the increasing number of corpora lutea, increasing progesterone concentration, and decreasing estradiol concentration. Furthermore, conception rate, prolificacy, and fecundity were improved compared with does that were not implanted during the nonbreeding season.


Assuntos
Criação de Animais Domésticos/métodos , Liberação Controlada de Fármacos , Fertilização/efeitos dos fármacos , Gonadotropinas Equinas/administração & dosagem , Melatonina/administração & dosagem , Reprodução/efeitos dos fármacos , Anestro , Animais , Implantes de Medicamento , Estradiol/sangue , Sincronização do Estro , Feminino , Fertilização/fisiologia , Cavalos , Lactação , Fase Luteal/efeitos dos fármacos , Fase Luteal/fisiologia , Folículo Ovariano/anatomia & histologia , Folículo Ovariano/efeitos dos fármacos , Gravidez , Progesterona/sangue , Reprodução/fisiologia , Estações do Ano
11.
Int J Oral Maxillofac Surg ; 44(2): 203-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25277806

RESUMO

The aim of the present study was to compare subjective experiences using bur, ultrasonic, and sonic osteotomy systems. Ten novice (N) and 10 expert (E) practitioners performed osteotomies on bovine ribs with each system. They scored ease of handling and sense of accuracy on visual analogue scales. The duration of the osteotomy procedure and the amount of noise were recorded objectively. Learning experience was evaluated in a second run. The Mann-Whitney U-test, Wilcoxon signed rank tests, and Spearman's rank correlation coefficient were used for the statistical analyses. The sonic system was significantly slower, with the worst noise impact (92.9dB; standard deviation (SD) 7.1). However, both user groups improved significantly in the second run (N 7.9, E 7.6). There were no significant differences in handling. The sense of accuracy was evaluated to be significantly best for the sonic system (N 8.4, E 8.4), compared to the ultrasonic system (N 7.1, E 7.1; both P=0.043) and bur system (N 5.5, P=0.002; E 6.0, P=0.006). The practitioners had a promising experience with the application of the ultrasonic system and particularly with the sonic system.


Assuntos
Osteotomia/métodos , Procedimentos Cirúrgicos Ultrassônicos/métodos , Animais , Bovinos , Competência Clínica , Desenho de Equipamento , Técnicas In Vitro , Osteotomia/instrumentação , Piezocirurgia , Projetos Piloto , Costelas/cirurgia , Procedimentos Cirúrgicos Ultrassônicos/instrumentação
12.
Med Hypotheses ; 82(6): 667-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24661941

RESUMO

Drug abuse is a serious problem associated with different pathological outcomes including modulating the immune system. Drug abuse is rising in Saudi Arabia and so as TB, a disease of worldwide significance, caused by immunological modulation in the host system. Khat chewing is a common practice in Arabian Peninsula which is now gaining momentum in other parts of the world. It is considered as an addiction. It has been associated with different adverse outcomes such as periodontitis, oral leukoplakia and oral cancer and also has shown to promote apoptotic cell death through cysteine proteases. The active ingredient of khat, cathinone is shown to have immunomodulatory effect. In principle, this leads to enhanced susceptibility to various infections. The present study is designed to delineate the mechanism of immunomodulation produced by khat/cathinone in human/mouse macrophage. Further, this activity will be evaluated both in vivo and in vitro in response to infection with Mycobacterium smegmatis to get an insight if there exists a co relation between the Mycobacterium tuberculosis infection and khat chewing.


Assuntos
Alcaloides/efeitos adversos , Catha/química , Suscetibilidade a Doenças/metabolismo , Imunomodulação/efeitos dos fármacos , Mycobacterium tuberculosis , Tuberculose/etiologia , Alcaloides/análise , Humanos , Mastigação/fisiologia , Modelos Biológicos , Mycobacterium smegmatis/metabolismo , Arábia Saudita , Transtornos Relacionados ao Uso de Substâncias
13.
Molecules ; 18(2): 1434-46, 2013 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-23348996

RESUMO

A series of twenty five 2-methylsulfanyl-[1,2,4]triazolo[1,5-a]quinazoline derivatives 1-25 was previously synthesized. We have now investigated their cytotoxic effects against hepatocellular Hep-G2 and colon HCT-116 carcinoma cells and effect on the macrophage growth, in addition to their influence of the inflammatory mediators [nitric oxide (NO), tumor necrosis factor-α (TNF-α), prostaglandin E-2 (PGE-2) and in bacterial lipopolysachharide (LPS)-stimulated macrophages]. The findings revealed that compounds 13 and 17 showed the highest cytotoxicity and that 3, 6-8 and 25 are promising multi-potent anti-inflammatory agents.


Assuntos
Anti-Inflamatórios/farmacologia , Quinazolinas/farmacologia , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dinoprostona/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Óxido Nítrico/metabolismo , Quinazolinas/síntese química , Quinazolinas/química , Fator de Necrose Tumoral alfa/metabolismo
14.
J Mater Sci Mater Med ; 22(5): 1195-203, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21445655

RESUMO

Recently, nano-macro dual-porous, three-dimensional (3D) glass structures were developed for use as bioscaffolds for hard tissue regeneration, but there have been concerns regarding the interconnectivity and homogeneity of nanopores in the scaffolds, as well as the cytotoxicity of the environment deep inside due to limited fluid access. Therefore, mercury porosimetry, nitrogen absorption, and TEM have been used to characterize nanopore network of the scaffolds. In parallel, viability of MG 63 human osteosarcoma cells seeded on scaffold surface was investigated by fluorescence, confocal and electron microscopy methods. The results show that cells attach, migrate and penetrate inside the glass scaffold with high proliferation and viability rate. Additionally, scaffolds were implanted under the skin of a male New Zealand rabbit for in vivo animal test. Initial observations show the formation of new tissue with blood vessels and collagen fibers deep inside the implanted scaffolds with no obvious inflammatory reaction. Thus, the new nano-macro dual-porous glass structure could be a promising bioscaffold for use in regenerative medicine and tissue engineering for bone regeneration.


Assuntos
Materiais Biocompatíveis , Engenharia Tecidual/métodos , Alicerces Teciduais , Animais , Técnica de Desmineralização Óssea , Compostos de Cálcio , Linhagem Celular Tumoral , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanoestruturas , Osteoblastos , Óxidos , Coelhos , Dióxido de Silício
15.
Int J Oral Maxillofac Surg ; 40(3): 285-91, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21163624

RESUMO

Bisphosphonates (BPs) are widely used as bone-stabilizers, but side effects of BP therapy include bisphosphonate-related osteonecrosis of the jaw (BRONJ), which is resistant to therapy. The aim of this study was to evaluate the outcome of maxillary BRONJ involving sinusitis maxillaris. 21 patients presenting with maxillary BRONJ, from 2005 to 2008, were included in the study. In 18 cases BP had been administered for carcinoma and in 3 cases for osteoporosis, with an average exposure time of 47.4 months. 12 patients spontaneously developed BRONJ. The 10 patients diagnosed with stage III BRONJ presented with concomitant sinusitis maxillaris. Despite treatment, there were six recurrences of BRONJ, four of them with additional sinusitis maxillaris. Whether BRONJ occurred spontaneously or after extraction there was no difference in the outcome. Patients with advanced maxillary BRONJ often suffer from sinusitis maxillaris, both of which are frequently resistant to therapy.


Assuntos
Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/efeitos adversos , Doenças Maxilares/induzido quimicamente , Sinusite Maxilar/induzido quimicamente , Osteonecrose/induzido quimicamente , Idoso , Idoso de 80 Anos ou mais , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Antibacterianos/uso terapêutico , Conservadores da Densidade Óssea/administração & dosagem , Carcinoma/tratamento farmacológico , Doença Crônica , Desbridamento , Difosfonatos/administração & dosagem , Feminino , Seguimentos , Humanos , Imidazóis/administração & dosagem , Imidazóis/efeitos adversos , Injeções Intravenosas , Masculino , Doenças Maxilares/terapia , Sinusite Maxilar/terapia , Pessoa de Meia-Idade , Osteonecrose/terapia , Osteoporose/tratamento farmacológico , Osteotomia , Recidiva , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Ácido Zoledrônico
16.
Clin Biochem ; 32(8): 621-6, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10638944

RESUMO

OBJECTIVES: The purpose of this study was to investigate the immunomodulatory effect of melatonin (MLT) on human peripheral blood mononuclear cells (PBMC) and to address its effects on Cis-platinum (CDDP)-induced cytotoxicity. METHODS AND RESULTS: The obtained data from this study revealed that treatment of cells with MLT (100 microg/ml) for 24 h enhanced cell viability. When cells were exposed to CDDP (5 microg/ml), cell proliferation in response to phytohaemagglutinin (PHA) stimulation was reduced by 49.63% compared to control cells as detected by 3[H]-thymidine uptake. Furthermore, Cis-platinum significantly depleted intracellular glutathione (GSH) levels by approximately 47% below that of untreated cells and led to apoptotic changes in the target cells as evidenced by DNA fragmentation (45% compared to 5% in control cells as measured by diphenylamine assay). DNA fragmentation was also confirmed by agarose gel electrophoresis. However, MLT enhanced cell proliferation by approximately 8.63% above the control values, and counteracted the antiproliferative effect of CDDP. The GSH levels were significantly increased in response to MLT (71% above control values) and it protected the cells against GSH depletion induced by CDDP. Moreover, DNA fragmentation and laddering produced by CDDP were significantly reduced or even disappeared when the cells were pretreated with MLT or the latter was simultaneously added with CDDP. CONCLUSIONS: The findings from this study indicated that melatonin is a potent immunomodulatory hormone that protects PBMC against cis-platinum-induced immunosuppressive effects. These effects might improve the patients' response to cis-platinum therapy and, therefore, their survival rates.


Assuntos
Adjuvantes Imunológicos/farmacologia , Cisplatino/farmacologia , Imunossupressores/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/imunologia , Melatonina/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular , Células Cultivadas , Fragmentação do DNA , Glutationa/sangue , Humanos , Cinética , Linfócitos/efeitos dos fármacos , Linfócitos/fisiologia , Fito-Hemaglutininas
17.
Middle East J Anaesthesiol ; 10(5): 499-505, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2233623

RESUMO

In two groups, each of 50 patients undergoing pulpectomy or multiple extractions, effects of combining xylocaine nerve block with halothane general anesthesia were studied. Local blockade of surgical stimuli reduced markedly the incidence of dysrhythmias occurring during halothane anesthesia. Recovery was faster and postoperative analgesia was enhanced.


Assuntos
Anestesia Dentária/efeitos adversos , Anestesia por Inalação/efeitos adversos , Anestesia Local , Arritmias Cardíacas/induzido quimicamente , Halotano/efeitos adversos , Adolescente , Adulto , Arritmias Cardíacas/prevenção & controle , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Lidocaína , Masculino
18.
Br J Oral Maxillofac Surg ; 28(2): 102-4, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2337559

RESUMO

In two groups, each of 50 patients undergoing oral surgery, effects of combining lidocaine nerve block with halothane general anaesthesia were studied. Local blockade of surgical stimuli reduced markedly the incidence of cardiac dysrhythmias occurred during halothane anaesthesia. Recovery was faster and post-operative analgesia was enhanced.


Assuntos
Anestesia Dentária , Anestesia Geral/efeitos adversos , Anestesia Local , Arritmias Cardíacas/prevenção & controle , Combinação de Medicamentos/uso terapêutico , Halotano/administração & dosagem , Lidocaína/administração & dosagem , Adolescente , Adulto , Período de Recuperação da Anestesia , Arritmias Cardíacas/induzido quimicamente , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Halotano/efeitos adversos , Humanos , Masculino , Bloqueio Nervoso
19.
Antimicrob Agents Chemother ; 32(6): 844-7, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3415205

RESUMO

Renal cyst infection in patients with polycystic kidney disease (PKD) is often unresponsive to standard antimicrobial therapy, in part because of the failure of most antibiotics to adequately penetrate cyst fluid. Ciprofloxacin, a new quinolone antibiotic, possesses in vitro activity against most pathogens likely to be encountered in renal cyst infection. To study the potential usefulness of ciprofloxacin for the treatment of cyst infection, fluid from 70 cysts was obtained from seven patients with polycystic kidney disease who were receiving the drug. Cysts were categorized as nongradient or gradient by the sodium concentration in the fluid. The ciprofloxacin concentration within cysts was measured, and the cyst fluid bactericidal activity against likely cyst fluid pathogens was determined. The mean (+/- standard error) ciprofloxacin concentration was 12.7 +/- 2.9 micrograms/ml. Preferential accumulation of ciprofloxacin occurred in gradient cysts; these levels exceeded levels in serum by more than fourfold. Cyst fluid bactericidal activity titers were uniformly high against Escherichia coli and Proteus mirabilis, while less activity was observed against Streptococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus, and Staphylococcus epidermidis.


Assuntos
Líquidos Corporais/metabolismo , Ciprofloxacina/metabolismo , Doenças Renais Policísticas/metabolismo , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Ophthalmic Surg ; 19(2): 124-7, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3347456

RESUMO

We describe a useful technique for removing filaria from the anterior chamber. In the case described, an immature female filaria approximately 15 mm in length was removed from the anterior chamber of a 32-year-old man in western Oregon and identified as a species of Dipetalonema. Features of four cases of filarial infection in the anterior chamber from the same geographic area are described. In three out of four cases, the worms were removed alive without difficulty by means of simple irrigation aspiration system.


Assuntos
Câmara Anterior/cirurgia , Filariose/cirurgia , Adulto , Câmara Anterior/parasitologia , Filariose/parasitologia , Humanos , Masculino , Métodos , Sucção , Irrigação Terapêutica
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