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1.
J Appl Microbiol ; 130(2): 325-340, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32797725

RESUMO

Cold plasma technology is an efficient, environmental-friendly, economic and noninvasive technology; and in recent years these advantages placed this novel technology at the centre of diverse studies for food industry applications. Dried food ingredients including spices, herbs, powders and seeds are an important part of the human diet; and the growing demands of consumers for higher quality and safe food products have led to increased research into alternative decontamination methods. Numerous studies have investigated the effect of nonthermal plasma on dried food ingredients for food safety and quality purposes. This review provides critical review on potential of cold plasma for disinfection of dried food surfaces (spices, herbs and seeds), improvement of functional and rheological properties of dried ingredients (powders, proteins and starches). The review further highlights the benefits of plasma treatment for enhancement of seeds performance and germination yield which could be applied in agricultural sector in near future. Different studies applying plasma technology for control of pathogens and spoilage micro-organisms and modification of food quality and germination of dried food products followed by benefits and current challenges are presented. However, more systemic research needs to be addressed for successful adoption of this technology in food industry.


Assuntos
Ingredientes de Alimentos/normas , Qualidade dos Alimentos , Alimentos em Conserva/normas , Gases em Plasma , Manipulação de Alimentos , Ingredientes de Alimentos/análise , Ingredientes de Alimentos/microbiologia , Inocuidade dos Alimentos , Alimentos em Conserva/análise , Alimentos em Conserva/microbiologia , Humanos
2.
Curr Med Chem ; 5(1): 63-72, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9481034

RESUMO

High performance liquid chromatography (HPLC) has proven to be an extremely useful analytical technique to separate and identify different types of hemoglobins, particularly A, C, F and S in blood samples, and compute their relative percentages. Such data provide useful information in the diagnosis of hemoglobinopathies including sickle cell anemia, beta-thalassemia, hemoglobin C disease,etc. In the present investigation, we have explored the determination of absolute concentrations of individual hemoglobins in g/dL and recommend it as an additional parameter which could be included as part of clinical data. Possible correlations between g/dL hemoglobin and the severity of a specific hemoglobinopathy could be established and aid in the diagnosis and/or treatment of such diseases. Several commercially available hemoglobin standards were analyzed and evaluated for use in creating g/dL calibration graphs for the HPLC. Appropriate calibration procedures have been developed and are presented. Also, linear regression graphs and sample chromatograms are included. Preliminary results obtained demonstrate the feasibility of using commercially available hemoglobin standards to calibrate an HPLC method for the estimation of absolute hemoglobin concentrations.


Assuntos
Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Hemoglobinas/análise , Padrões de Referência , Hemoglobinopatias/diagnóstico , Kit de Reagentes para Diagnóstico , Análise de Regressão , Traço Falciforme/diagnóstico
3.
Curr Med Chem ; 7(6): 593-608, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10702628

RESUMO

Transdermal drug delivery (TDD) is the administration of therapeutic agents through intact skin for systemic effect. TDD offers several advantages over the conventional dosage forms such as tablets, capsules and injections. Currently there are about eight drugs marketed as transdermal patches. Examples of such products include nitroglycerin (angina pectoris), clonidine (hypertension), scopolamine (motion sickness), nicotine (smoking cessation), fentanil (pain) and estradiol (estrogen deficiency). Since skin is an excellent barrier for drug transport, only potent drugs with appropriate physicochemical properties (low molecular weight, adequate solubility in aqueous and non-aqueous solvents, etc) are suitable candidates for transdermal delivery. Penetration enhancement technology is a challenging development that would increase significantly the number of drugs available for transdermal administration. The permeation of drugs through skin can be enhanced by physical methods such as iontophoresis (application of low level electric current) and phonophoresis (use of ultra sound energy) and by chemical penetration enhancers (CPE). In this review, we have discussed about the CPE which have been investigated for TDD. CPE are compounds that enhance the permeation of drugs across the skin. The CPE increase skin permeability by reversibly altering the physicochemical nature of the stratum corneum, the outer most layer of skin, to reduce its diffusional resistance. These compounds increase skin permeability also by increasing the partition coefficient of the drug into the skin and by increasing the thermodynamic activity of the drug in the vehicle. This review compiles the various CPE used for the enhancement of TDD, the mechanism of action of different chemical enhancers and the structure-activity relationship of selected and extensively studied enhancers such as fatty acids, fatty alcohols and terpenes. Based on the chemical structure of penetration enhancers (such as chain length, polarity, level of unsaturation and presence of some special groups such as ketones), the interaction between the stratum corneum and penetration enhancers may vary which will result in significant differences in penetration enhancement. Our review also discusses the various factors to be considered in the selection of an appropriate penetration enhancer for the development of transdermal delivery systems.


Assuntos
Administração Cutânea , Sistemas de Liberação de Medicamentos , Química Farmacêutica , Humanos , Pele/anatomia & histologia , Absorção Cutânea , Relação Estrutura-Atividade
4.
Rev Cardiovasc Med ; 2 Suppl 2: S2-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12439355

RESUMO

This article reviews the current understanding of the pathophysiology and clinical spectrum of heart failure. A cascade of hemodynamic and neurohormonal derangements result from a decrease in ventricular performance or cardiac output. Because neurohormonal activation has become a target for intervention in heart failure, the role of selected systems (sympathetic nervous, renin-angiotensin-aldosterone) and of natriuretic peptides is detailed. The spectrum (from compensated to acute decompensated) within which congestive heart failure patients present is reviewed, with special attention paid to the intermediate, transitional group of patients, who pose unique diagnostic and therapeutic challenges. Given these variable presentations, there is an obligation to tailor therapy accordingly.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Sistema Renina-Angiotensina/fisiologia , Fator Natriurético Atrial/fisiologia , Insuficiência Cardíaca/classificação , Insuficiência Cardíaca/diagnóstico , Humanos , Sistema Nervoso Simpático/fisiopatologia
5.
Malays J Pathol ; 15(2): 131-6, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8065174

RESUMO

Seventy-eight symptomatic females without palpable breast lumps were subjected to bilateral four quadrant fine needle aspiration cytology. Cytological evidence of an epithelial proliferative lesion was seen in 44 of these cases. Based on the cytological evidence of proliferation, the site for open biopsy was determined. Histopathological study of the breast biopsies in these patients showed proliferative disease without atypia (PDWA) in 40 cases, atypical ductal hyperplasia (ADH) in two, atypical lobular hyperplasia (ALH) in one and ADH with ALH in one case. Cytology was thus useful in establishing the presence of proliferative activity, commenting on the extent of proliferation, and thereby roughly mapping out the area of the breast most suitable for biopsy. On cytological grounds, it was not possible to distinguish the atypical hyperplastic lesions from the proliferative diseases without atypia.


Assuntos
Biópsia por Agulha/métodos , Doenças Mamárias/patologia , Divisão Celular/fisiologia , Feminino , Humanos , Palpação
6.
Malays J Pathol ; 15(2): 137-42, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8065175

RESUMO

Forty-eight patients with breast carcinoma were subjected to four quadrant fine needle aspiration (FNA) cytology examination of the ipsilateral and contralateral breast in an attempt to detect any accompanying benign proliferative lesion. Mastectomy of ipsilateral and open biopsy of contralateral breast provided material for histopathological study. Cytological evidence of epithelial proliferation was found in 8 (16.6%) cases which included atypical lobular hyperplasia (ALH), lobular neoplasia in-situ (LNIS), atypical ductal hyperplasia (ADH), and proliferative disease without atypia (PDWA). In lobular proliferative lesions, cytological smears showed configurations of cells that resembled filled up or expanded lobular units. The cytology was not distinctive enough to distinguish the sub-types of lobular proliferations. Likewise, the presence of ductal alterations could be suggested by cytological study but the distinction of proliferative disease without atypia (PDWA) from atypical ductal hyperplasia (ADH) was not possible on a cytological basis.


Assuntos
Biópsia por Agulha/métodos , Neoplasias da Mama/patologia , Adulto , Idoso , Divisão Celular/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
Phys Rev B Condens Matter ; 52(11): 7972-7975, 1995 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9979794
13.
Oncogene ; 27(42): 5648-50, 2008 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-18504432

RESUMO

The serine-threonine kinase AKT1 is a central player in the oncogenic pathway controlled by PI3K. Recently, a somatic mutation in AKT1 (E17K) has been detected in breast, colorectal, lung and ovarian cancers. The E17K change results in constitutive AKT1 activation and induces leukaemia in mice. We determined the occurrence of the E17K variant in a panel of 764 tumour samples. These included breast, lung, ovarian, colorectal and pancreatic carcinomas as well as melanomas and glioblastomas. Despite the fact that these tumours are known to bear alterations in genes involved in the PI3K signalling pathway, AKT1(E17K) was detected only in breast (16/273), colorectal (1/88) and lung (1/155) cancers. Within the neoplasms of breast origin, the AKT1(E17K) variant was mutually exclusive with respect to the PIK3CA(E454K or H1047R) alleles and was present only in ductal and lobular histotypes. Our results, showing that AKT1 mutations seem to occur in a tissue-specific fashion have basic and clinical implications. First, the activity of mutated AKT1 in oncogenic PI3K signalling could be strictly dependent on the cell and tissue milieu. Second, therapeutic efforts aimed at selective targeting the AKT1(E17K) variant could be effective mainly in specific cancer types.


Assuntos
Mutação , Neoplasias/genética , Proteínas Proto-Oncogênicas c-akt/genética , Classe I de Fosfatidilinositol 3-Quinases , Humanos , Especificidade de Órgãos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/fisiologia
14.
Br J Dermatol ; 144 Suppl 58: 27-32, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11501510

RESUMO

Monotherapy with vitamin D analogues has been shown to be effective in the treatment of psoriasis. Vitamin D analogues have also been used in combination with other topical therapies, systemic therapies and phototherapy. In many instances, the efficacy of these other treatments can be maximized and adverse effects minimized when combined with vitamin D analogues. The combination of a topical corticosteroid with a vitamin D analogue can work synergistically to improve efficacy and reduce the side-effects from both treatments. However, caution must be used when mixing the two agents, as some topical corticosteroids will result in the degradation of the vitamin D analogue. Benefit from phototherapy is also increased when using vitamin D analogues, so that greater improvement occurs with fewer treatments. Effects on minimal erythema dose must be considered and the potential for ultraviolet blocking by vitamin D analogues may affect treatment. Some vitamin D analogues may also be susceptible to degradation by certain wavelengths of ultraviolet light. Combining vitamin D analogues with systemic agents exerts a dose-sparing effect, thus reducing the possibility of side-effects, but such combinations require further study. As long as treatments are used correctly, the benefits of combination therapy with vitamin D analogues usually outweigh the few drawbacks.


Assuntos
Fármacos Dermatológicos/uso terapêutico , Psoríase/tratamento farmacológico , Vitamina D/análogos & derivados , Calcitriol/análogos & derivados , Calcitriol/uso terapêutico , Terapia Combinada , Quimioterapia Combinada , Humanos , Fototerapia , Terapia Ultravioleta , Vitamina D/uso terapêutico
15.
Heart Fail Rev ; 5(1): 7-16, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16228912

RESUMO

In the failing heart, several changes occur in cardiac adrenergic receptor-signal transduction pathways. The most striking of these changes occur in beta-ARs, and of the changes in beta-adrenergic receptors, beta1-receptor down-regulation is the most prominent. Other changes include uncoupling of beta2-adrenergic receptors and increased activity of the inhibitory G-protein, Gi. Most of these changes appear to be related to increased activity of the adrenergic nervous system, i.e. increased exposure to norepinephrine. Antagonists of the adrenergic nervous system improve left ventricular function and outcome in patients with heart failure. This fact supports the notion that activation of these neurohormonal systems exerts a net long-term detrimental effect on the natural history of chronic heart failure and that myocardial adrenergic desensitization phenomena are at least partially adaptive in the setting of left ventricular dysfunction.


Assuntos
Insuficiência Cardíaca/fisiopatologia , Norepinefrina/metabolismo , Receptores Adrenérgicos/fisiologia , Transdução de Sinais/fisiologia , Animais , Regulação para Baixo , Feminino , Humanos , Masculino , Camundongos , Receptores Adrenérgicos/metabolismo , Receptores Adrenérgicos alfa/metabolismo , Receptores Adrenérgicos alfa/fisiologia , Receptores Adrenérgicos beta/metabolismo , Receptores Adrenérgicos beta/fisiologia , Sensibilidade e Especificidade
16.
J Card Fail ; 6(4): 359-68, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11145761

RESUMO

Despite conventional therapy, there is still much room for improvement in the prognosis of patients with chronic systolic heart failure. Evidence supports a role for endothelin-1 (ET-1), a potent vasoconstrictor, in the pathophysiology of heart failure. Given its potentially deleterious effects, the optimal treatment of heart failure may need to include efforts directed toward antagonizing this hormone. In support of this notion, the use of ET receptor antagonists produces a number of beneficial effects in heart failure, including both improvements in hemodynamics and reductions in the levels of other vasoconstricting neurohormones. There are at least 2 receptors for ET-1 (the ET-A and ET-B receptor), and the effects of ET-1 binding differ depending on the receptor involved. It is still unclear whether blockade of the ET-A receptor alone or the combined blockade of both the ET-A and ET-B receptors will be most efficacious as a therapeutic strategy. Long-term benefits have been achieved with the use of a mixed ET-A/B receptor antagonist, when added to standard triple-drug therapy, in patients with severe heart failure. We await the results of ongoing trials to determine if these agents will fulfill the promise of adding substantial incremental benefit to the treatment of the disease.


Assuntos
Antagonistas dos Receptores de Endotelina , Endotelina-1/fisiologia , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/etiologia , Bosentana , Ácidos Carboxílicos/farmacologia , Ácidos Carboxílicos/uso terapêutico , Doença Crônica , Insuficiência Cardíaca/fisiopatologia , Humanos , Indanos/farmacologia , Indanos/uso terapêutico , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Prognóstico , Piridinas/farmacologia , Piridinas/uso terapêutico , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Receptores de Endotelina/classificação , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Resultado do Tratamento
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