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1.
J Phys Chem Lett ; 15(13): 3627-3638, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38530393

RESUMO

Metalloporphyrins with open d-shell ions can drive biochemical energy cycles. However, their utilization in photoconversion is hampered by rapid deactivation. Mapping the relaxation pathways is essential for elaborating strategies that can favorably alter the charge dynamics through chemical design and photoexcitation conditions. Here, we combine transient optical absorption spectroscopy and transient X-ray emission spectroscopy with femtosecond resolution to probe directly the coupled electronic and spin dynamics within a photoexcited nickel porphyrin in solution. Measurements and calculations reveal that a state with charge-transfer character mediates the formation of the thermalized excited state, thereby advancing the description of the photocycle for this important representative molecule. More generally, establishing that intramolecular charge-transfer steps play a role in the photoinduced dynamics of metalloporphyrins with open d-shell sets a conceptual ground for their development as building blocks capable of boosting nonadiabatic photoconversion in functional architectures through "hot" charge transfer down to the attosecond time scale.

2.
Toxicol Mech Methods ; 34(4): 385-397, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38083807

RESUMO

Polymeric poly (lactic-co-glycolic acid) (PLGA)-lipid hybrid nanoparticles (PNPs)-based therapy are powerful carriers for various therapeutic agents. This study was conducted to evaluate the chemotherapeutic potential of free 5-flurouracil (5FU) and synthetized 5FU-PNPs and impact on p53-dependent apoptosis in mammary carcinomas (MCs) grown in mice. Breast cancer cells were injected in Swiss albino female mice and 2 bilateral masses of MC were confirmed after one week. Mice were distributed to five experimental groups; Group 1: MC control group. Groups 2 and 3: MC + free 5FU [5 or 10 mg per kg] groups. Groups 4 and 5: synthetized MC+ 5FU-PNPs [5 or 10 mg per kg] groups. Medications were administered orally, twice weekly for 3 weeks. Then, tumors were dissected, and sections were stained with hematoxylin-eosin (HE) while the other MC was used for measuring of cell death and inflammatory markers. Treatment with 5FU-PNPs suppressed the MC masses and pathologic scores based on HE-staining. Similarly, greater proapoptotic activity was recorded in 5FU-PNPs groups compared to free 5FU groups as shown by significant upregulation in tumoral p53 immunostaining. The current results encourage the utility of PNPs for improving the antitumor effect of 5FU. The chemotherapeutic potential was mediated through enhancement of tumoral p53-mediated p53 up-regulated modulator of apoptosis (PUMA) genes. Additional studies are warranted for testing the antitumor activity of this preparation in other mouse models of breast cancer.

3.
ChemSusChem ; 13(12): 3252-3260, 2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32149460

RESUMO

Photocatalytic water splitting has become a promising strategy for converting solar energy into clean and carbon-neutral solar fuels in a low-cost and environmentally benign way. Hydrogen gas is such a potential solar fuel/energy carrier. In a classical artificial photosynthetic system, a photosensitizer is generally associated with a co-catalyst to convert photogenerated charge into (a) chemical bond(s). In the present study, assemblies consisting of CdSe quantum dots that are coupled with one of two molecular complexes/catalysts, that is, [Fe2 S2 (CO)6 ] or [Fe3 Te2 (CO)9 ], using an interface-directed approach, have been tested as catalytic systems for hydrogen production in aqueous solution/organic solution. In the presence of ascorbic acid as a sacrificial electron donor and proton source, these assemblies exhibit enhanced activities for the rate of hydrogen production under visible light irradiation for 8 h in aqueous solution at pH 4.0 with up to 110 µmol of H2 per mg of assembly, almost 8.5 times that of pure CdSe quantum dots under the same conditions. Transient absorption and time-resolved photoluminescence spectroscopies have been used to investigate the charge carrier transfer dynamics in the quantum dot/iron carbonyl cluster assemblies. The spectroscopic results indicate that effective electron transfer from the molecular iron complex to the valence band of the excited CdSe quantum dots significantly inhibits the recombination of photogenerated charge carriers, boosting the photocatalytic activity for hydrogen generation; that is, the iron clusters function as effective intermediaries for electron transfer from the sacrificial electron donor to the valence band of the quantum dots.

4.
Turk J Gastroenterol ; 30(8): 708-713, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31418415

RESUMO

BACKGROUND/AIMS: There is less data regarding the changes in body mass index (BMI) after treating hepatitis C virus (HCV) patients with new direct-acting antiviral agents (DAAs). This study aimed to assess the changes in BMI in chronic HCV patients treated with DAAs in Egypt and to explore other factors influencing this change. MATERIALS AND METHODS: The data of chronic HCV patients who received antiviral therapy with new DAAs in one of Egypt's specialized viral hepatitis treatment centers were retrospectively analyzed. In addition to the routine clinical and laboratory workup, changes in body weight during and after treatment were monitored and BMI was calculated. Viral load was measured at 12 weeks post-treatment to assess a sustained virological response. Patients with documented thyroid abnormalities, bariatric surgery, or ensuing special diets were excluded. BMI of >30 was taken as the cutoff for pa¬tients with obesity. RESULTS: The study included 162 patients with a mean age of 48.56±11.49 years, of whom 61.1% were males, 16% were treatment-experienced, 12% were diabetic, and 29% were obese. Treatment duration was 12 weeks in 84% of patients and 24 weeks in 16% of patients. There was a significant increase in BMI post-treatment as compared to pretreatment measures (28.68±5.35 vs 28.18±4.55) (p=0.03). BMI changes were constant regardless of cirrhosis or previous treatment experience. CONCLUSION: Treatment of chronic HCV with DAAs was associated with increased body mass index. Further studies are needed to explore if this effect is secondary to treatment with DAAs or is an improvement in the liver function and lifestyle of treated patients.


Assuntos
Antivirais/efeitos adversos , Índice de Massa Corporal , Peso Corporal/efeitos dos fármacos , Hepacivirus , Hepatite C Crônica/tratamento farmacológico , Adulto , Feminino , Hepatite C Crônica/fisiopatologia , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resposta Viral Sustentada
5.
Arab J Gastroenterol ; 20(2): 109-113, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31175077

RESUMO

Liver diseases are among the most challenging health care problems worldwide. In Egypt, we established different care programs to combat liver diseases including schistosomiasis and viral hepatitides. A lot of research work addressing liver diseases in Egypt have been published with special focus on these two major fields. Other liver disease seems to be neglected although present and contributing to the liver disease burden in Egypt. In this report we reviewed the available evidence published from Egypt and elucidate areas of weakness and future research needs. Our search for Egyptian liver disease evidence retrieved 4683 articles, 67% of them were relevant to the topic. Out of the relevant articles; 1646/3265 (50.4%) were discussing clinical science, 1131 (34.7%) were discussing basic science and 488 (14.9%) were discussing both basic and clinical sciences. Cairo university (16.8%, n = 513) and Mansoura university (9.3%, n = 285) had the largest number of publications related to liver disease in Egypt respectively. The most commonly reported diseases were hepatitis C in 719/3361 articles (21.4%), parasitic liver infestations in 663 articles (19.7%), hepatocellular carcinoma in 544 articles (16.2%), liver fibrosis or cirrhosis in 537 articles (16%), and drug induced liver injury in 516 articles (15.4%). Most of the reviewed articles (36%) were discussing treatment of chronic liver diseases (n = 1201) followed by diagnostics (28%, n = 940), pathogenesis and pathophysiology (21%, n = 706). This review will direct attention to areas with less research like hepatitis B related liver disease, HIV/HCV co-infections, and non-alcoholic fatty liver disease (NAFLD) to encourage future research in these topics. In conclusion; our results ring a bell inviting the development of a roadmap for liver research in Egypt targeting to put future policies to cover areas of weakness in liver research with an ultimate goal of tackling liver disease and its overwhelming socioeconomic burden in our developing country.


Assuntos
Bibliometria , Pesquisa Biomédica , Hepatopatias/diagnóstico , Hepatopatias/terapia , Egito , Humanos , Hepatopatias/etiologia
6.
World J Gastroenterol ; 24(38): 4330-4340, 2018 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-30344418

RESUMO

Worldwide, more than one million people die each year from hepatitis C virus (HCV) related diseases, and over 300 million people are chronically infected with hepatitis B or C. Egypt used to be on the top of the countries with heavy HCV burden. Some countries are making advances in elimination of HCV, yet multiple factors preventing progress; remain for the majority. These factors include lack of global funding sources for treatment, late diagnosis, poor data, and inadequate screening. Treatment of HCV in Egypt has become one of the top national priorities since 2007. Egypt started a national treatment program intending to provide cure for Egyptian HCV-infected patients. Mass HCV treatment program had started using Pegylated interferon and ribavirin between 2007 and 2014. Yet, with the development of highly-effective direct acting antivirals (DAAs) for HCV, elimination of viral hepatitis has become a real possibility. The Egyptian National Committee for the Control of Viral Hepatitis did its best to provide Egyptian HCV patients with DAAs. Egypt adopted a strategy that represents a model of care that could help other countries with high HCV prevalence rate in their battle against HCV. This review covers the effects of HCV management in Egyptian real life settings and the outcome of different treatment protocols. Also, it deals with the current and future strategies for HCV prevention and screening as well as the challenges facing HCV elimination and the prospect of future eradication of HCV.


Assuntos
Antivirais/uso terapêutico , Erradicação de Doenças/organização & administração , Hepacivirus/isolamento & purificação , Hepatite C Crônica/prevenção & controle , Programas Nacionais de Saúde/organização & administração , Erradicação de Doenças/métodos , Erradicação de Doenças/estatística & dados numéricos , Quimioterapia Combinada/métodos , Egito/epidemiologia , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/virologia , Humanos , Programas de Rastreamento/métodos , Programas de Rastreamento/organização & administração , Programas de Rastreamento/estatística & dados numéricos , Programas Nacionais de Saúde/estatística & dados numéricos , Prevalência
7.
BMJ Case Rep ; 20112011 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-22688484

RESUMO

A 55-year-old Egyptian woman with chronic hepatitis C undergoing treatment with pegylated interferon (Peg-IFN) alfa-2a plus ribavirin was referred to our hospital on November 2010 with prolonged easy fatigability and an attack of syncope; she had no prior history of autoimmune disorders or allergy. Laboratory investigations documented the presence of Peg-IFN induced autoimmune haemolytic anaemia and autoimmune thyroiditis. Intravenous γ globulin (IVGG) failed to correct the autoimmune process; on the other hand steroid therapy dramatically corrected both haematological and thyroid values, and step down the immune process. Our report indicated that Peg-IFN de novo-induce autoimmune haemolysis, documenting a previous report. IVGG failed to step down the immune process in our case.


Assuntos
Anemia Hemolítica Autoimune/induzido quimicamente , Antivirais/efeitos adversos , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/efeitos adversos , Polietilenoglicóis/efeitos adversos , Tireoidite Autoimune/induzido quimicamente , Anemia Hemolítica Autoimune/diagnóstico , Diagnóstico Diferencial , Quimioterapia Combinada , Feminino , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Pessoa de Meia-Idade , Proteínas Recombinantes/efeitos adversos
8.
Bioinorg Chem Appl ; : 542979, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19390627

RESUMO

Organotin(IV) complexes with o- or p-hydroxybenzoic acids (o-H(2)BZA or p-H(2)BZA) of formulae [R(2)Sn(HL)(2)] (where H(2)L = o-H(2)BZA and R = Me- (1), n-Bu- (2)); [R(3)Sn(HL)] (where H(2)L = o-H(2)BZA and R = n-Bu- (3), Ph- (4) or H(2)L = p-H(2)BZA and R = n-Bu- (5), Ph- (6)) were synthesized by reacting a methanolic solution of di- and triorganotin(IV) compounds with an aqueous solution of the ligand (o-H(2)BZA or p-H(2)BZA) containing equimolar amounts of potassium hydroxide. The complexes were characterized by elemental analysis, FT-IR, Far-IR, TGA-DTA, FT-Raman, Mössbauer spectroscopy, (1)H, (119)Sn-NMR, UV/Vis spectroscopy, and Mass spectroscopy. The X-ray crystal structures of complexes 1 and 2 have also been determined. Finally, the influence of these complexes 1-6 upon the catalytic peroxidation of linoleic acid to hydroperoxylinoleic acid by the enzyme lipoxygenase (LOX) was kinetically studied and the results showed that triorganotin(IV) complex 6 has the lowest IC(50) value. Also complexes 1-6 were studied for their in vitro cytotoxicity against sarcoma cancer cells (mesenchymal tissue) from the Wistar rat, and the results showed that the complexes have high activity against these cell lines with triphenyltin((IV) complex 4 to be the most active one.

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