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1.
Poult Sci ; 96(6): 1884-1890, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28339753

RESUMO

Previous studies demonstrated that in ovo photostimulation with monochromatic green light increases body weight and accelerates muscle development in broilers. The mechanism in which in ovo photostimulation accelerates growth and muscle development is not clearly understood. The objective of the current study was to define development of the somatotropic axis in the broiler embryo associated with in ovo green light photostimulation. Two-hundred-forty fertile broiler eggs were divided into 2 groups. The first group was incubated under intermittent monochromatic green light using light-emitting diode (LED) lamps with an intensity of 0.1 W\m2 at shell level, and the second group was incubated under dark conditions and served as control. In ovo green light photostimulation increased plasma growth hormone (GH) and prolactin (PRL) levels, as well as hypothalamic growth hormone releasing hormone (GHRH), liver growth hormone receptor (GHR), and insulin-like growth factor-1 (IGF-1) mRNA levels. The in ovo photostimulation did not, however, increase embryo's body weight, breast muscle weight, or liver weight. The results of this study suggest that stimulation with monochromatic green light during incubation increases somatotropic axis expression, as well as plasma prolactin levels, during embryonic development.


Assuntos
Embrião de Galinha/crescimento & desenvolvimento , Embrião de Galinha/efeitos da radiação , Luz , Animais , Peso Corporal/efeitos da radiação , Hormônio do Crescimento/sangue , Hormônio do Crescimento/efeitos da radiação , Hormônio Liberador de Hormônio do Crescimento/análise , Hormônio Liberador de Hormônio do Crescimento/efeitos da radiação , Hipotálamo/metabolismo , Hipotálamo/efeitos da radiação , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/efeitos da radiação , Fígado/embriologia , Fígado/efeitos da radiação , Óvulo/efeitos da radiação , Músculos Peitorais/embriologia , Músculos Peitorais/efeitos da radiação , Prolactina/sangue , Prolactina/efeitos da radiação , RNA Mensageiro , Receptores da Somatotropina/efeitos da radiação
2.
Oral Dis ; 22 Suppl 1: 73-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27109275

RESUMO

More than 37 million people are living with human immunodeficiency virus 1 (HIV), and more people than ever received lifesaving antiretroviral therapy worldwide. HIV-1 infection disrupts the intestinal immune system, leading to microbial translocation and systemic immune activation. We investigated the impact of HIV-1 infection on the GI microbiome and its association with host immune activation. The data indicated that the microbiome was different in HIV-positive and HIV-negative individuals. The initial sequence analysis of saliva indicated that there were major differences in the phyla of Bacteroidetes, Firmicutes, Proteobacteria, and TM7. Phylum Tenericutes was only seen in HIV-positive saliva. At the family level, we identified differences in Streptococcacea, Prevotellaceae, Porphyromonadaceae, and Neisseriaceae, whereas data from various sites in GI tract indicated that Prevotella melaninigencia, Fusobacterium necrophorum, Burkholderia, Bradyrhizobium, Ralstonia, and Eubacterium biforme were predominant but differentially present at various sites. Furthermore, there was a decrease in seven proteins associated with the alternative complement pathway and an increase in 6 proteins associated with the lectin and classical complement pathways. The correlation with a shift in complement pathways suggests that compromised immunity could be responsible for the observed dysbiosis in the GI microbiome.


Assuntos
Ativação do Complemento , Microbioma Gastrointestinal , Infecções por HIV/microbiologia , Saliva/microbiologia , Fármacos Anti-HIV/uso terapêutico , Translocação Bacteriana/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Humanos
3.
Oral Dis ; 22 Suppl 1: 166-70, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27109284

RESUMO

Recent years have seen a massive expansion in our understanding of how we interact with our microbial colonists. The development of new, rapid sequencing techniques such as pyrosequencing and other next-generation sequencing systems have enabled us to begin to characterise the constituents of our diverse microbial communities, revealing the astonishing genetic richness that is our microbiome. Despite this, our ignorance of how these communities change over the course of an HIV infection is profound. Whilst some steps have been made to characterise the HIV microbiome at selected sites, these reports are still limited and much remains to be done. It has become apparent, however, that host-microbiota interactions are perturbed during HIV infections, with microbial translocation of potential pathogens linked to a variety of different HIV complications, including more rapid progression of disease. The use of probiotics and prebiotics has been investigated as treatments to alleviate symptoms for a variety of conditions, and is now being proposed for the treatment of symptoms associated with HIV. However, this is a new area of investigations and many questions remain unanswered. What we know about both of these topics is a drop in the ocean compared with what we need to know. In this article, we report on a workshop where these two major under-investigated research areas were presented, and future directions explored and discussed.


Assuntos
Microbioma Gastrointestinal , Infecções por HIV/microbiologia , Infecções por HIV/terapia , Boca/microbiologia , Probióticos/uso terapêutico , Congressos como Assunto , Infecções por HIV/prevenção & controle , Humanos
4.
Oral Dis ; 22 Suppl 1: 171-80, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27109285

RESUMO

The interplay between HIV-1 and epithelial cells represents a critical aspect in mucosal HIV-1 transmission. Epithelial cells lining the oral cavity cover subepithelial tissues, which contain virus-susceptible host cells including CD4(+) T lymphocytes, monocytes/macrophages, and dendritic cells. Oral epithelia are among the sites of first exposure to both cell-free and cell-associated virus HIV-1 through breast-feeding and oral-genital contact. However, oral mucosa is considered to be naturally resistant to HIV-1 transmission. Oral epithelial cells have been shown to play a crucial role in innate host defense. Nevertheless, it is not clear to what degree these local innate immune factors contribute to HIV-1 resistance of the oral mucosa. This review paper addressed the following issues that were discussed at the 7th World Workshop on Oral Health and Disease in AIDS held in Hyderabad, India, during November 6-9, 2014: (i) What is the fate of HIV-1 after interactions with oral epithelial cells?; (ii) What are the keratinocyte and other anti-HIV effector oral factors, and how do they contribute to mucosal protection?; (iii) How can HIV-1 interactions with oral epithelium affect activation and populations of local immune cells?; (iv) How can HIV-1 interactions alter functions of oral epithelial cells?


Assuntos
Células Epiteliais/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata , Congressos como Assunto , Células Epiteliais/fisiologia , Humanos , Imunidade nas Mucosas , Queratinócitos/imunologia
5.
J Dent Res ; 91(9): 834-40, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22821240

RESUMO

We report a clinical study that examines whether HIV infection affects Streptococcus mutans colonization in the oral cavity. Whole stimulated saliva samples were collected from 46 HIV-seropositive individuals and 69 HIV-seronegative control individuals. The level of S. mutans colonization was determined by conventional culture methods. The genotype of S. mutans was compared between 10 HIV-positive individuals before and after highly active antiretroviral therapy (HAART) and 10 non-HIV-infected control individuals. The results were analyzed against viral load, CD4+ and CD8+ T-cell counts, salivary flow rate, and caries status. We observed that S. mutans levels were higher in HIV-infected individuals than in the non-HIV-infected control individuals (p = 0.013). No significant differences in S. mutans genotypes were found between the two groups over the six-month study period, even after HAART. There was a bivariate linear relationship between S. mutans levels and CD8+ counts (r = 0.412; p = 0.007), but not between S. mutans levels and either CD4+ counts or viral load. Furthermore, compared with non-HIV-infected control individuals, HIV-infected individuals experienced lower salivary secretion (p = 0.009) and a positive trend toward more decayed tooth surfaces (p = 0.027). These findings suggest that HIV infection can have a significant effect on the level of S. mutans, but not genotypes.


Assuntos
Infecções por HIV/microbiologia , Saliva/microbiologia , Streptococcus mutans/genética , Streptococcus mutans/isolamento & purificação , Adulto , Idoso , Análise de Variância , Terapia Antirretroviral de Alta Atividade , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Contagem de Colônia Microbiana , Índice CPO , Cárie Dentária/complicações , Feminino , Genótipo , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Hospedeiro Imunocomprometido , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Saliva/metabolismo , Taxa Secretória , Estatísticas não Paramétricas , Adulto Jovem
6.
Adv Dent Res ; 23(4): 375-80, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21917748

RESUMO

There have been significant advances in techniques for the detection of biomarker signals in the oral cavity (e.g., ELISAs for proteins, PCR for RNA and DNA) as well as the engineering and development of microfluidic approaches to make oral-based point-of-care (POC) methods for the diagnosis for both local and systemic conditions a reality. In this section, we focus on three such approaches, namely, periodontal disease management, early markers for systemic diseases, and salivary markers useful for pharmacogenomic studies. Novel approaches using non-invasive, salivary samples and user-friendly devices offer results that are as sensitive and specific as laboratory-based analyses using blood or urine.


Assuntos
Diagnóstico Bucal/métodos , Saliva/química , Pesquisa Translacional Biomédica , Biomarcadores , Doenças Cardiovasculares/diagnóstico , Testes de Química Clínica/métodos , Testes Genéticos , Humanos , Dispositivos Lab-On-A-Chip , Microfluídica/instrumentação , Periodontite/diagnóstico , Farmacogenética , Sistemas Automatizados de Assistência Junto ao Leito
7.
Oral Dis ; 17(8): 745-52, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21521419

RESUMO

Many of the target molecules that reside in blood are also present in oral fluids, albeit at lower concentrations. Oral fluids are, however, relatively easy and safe to collect without the need for specialized equipment and training. Thus, oral fluids provide convenient samples for medical diagnostics. Recent advances in lab-on-a-chip technologies have made minute, fully integrated diagnostic systems practical for an assortment of point-of-care tests. Such systems can perform either immunoassays or molecular diagnostics outside centralized laboratories within time periods ranging from minutes to an hour. The article briefly reviews recent advances in devices for point-of-care testing with a focus on work that has been carried out by the authors as part of a NIH program.


Assuntos
Diagnóstico Bucal/instrumentação , Dispositivos Lab-On-A-Chip , Sistemas Automatizados de Assistência Junto ao Leito , Desenho de Equipamento , Líquido do Sulco Gengival/química , Humanos , Imunoensaio/instrumentação , Microfluídica/instrumentação , Técnicas de Diagnóstico Molecular/instrumentação , Saliva/química , Fatores de Tempo
8.
Adv Dent Res ; 23(1): 34-7, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21441478

RESUMO

In this review, the authors survey the large number of antibacterial and antiviral proteins present in human saliva. Of interest, most of these antibacterial proteins display antiviral activity, typically against specific viral pathogens. The review focuses on one protein that interacts with both bacteria and viruses-gp340, originally referred to as salivary agglutinin. In the oral cavity, soluble gp340 binds to and aggregates a variety of bacteria, and this is thought to increase bacterial clearance from the mouth. However, when bound to the tooth surface, gp340 promotes bacterial adherence. In the oral cavity, most gp340 is found soluble in saliva and can function as a specific inhibitor of infectivity of HIV-1 and influenza A. In contrast, in the female reproductive track, most gp340 is bound to the cell surface, where it can promote HIV-1 infection.


Assuntos
Peptídeos Catiônicos Antimicrobianos/fisiologia , Antivirais , Infecções por HIV/metabolismo , Receptores de Superfície Celular/fisiologia , Proteínas e Peptídeos Salivares/fisiologia , Antivirais/metabolismo , Aderência Bacteriana , Proteínas de Ligação ao Cálcio , Proteínas de Ligação a DNA , HIV-1/metabolismo , Humanos , Vírus da Influenza A/metabolismo , Modelos Moleculares , Orthomyxoviridae , Ligação Proteica , Conformação Proteica , Receptores de Superfície Celular/química , Proteínas Supressoras de Tumor
9.
Adv Dent Res ; 23(1): 137-41, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21441495

RESUMO

Diagnostic tests for a range of oral and systemic diseases using fluids sampled from the mouth are under intense investigation and are increasingly being used. Methods exist for identification of HIV antibody and nucleic acid and for other viral infections of the mouth, such as Kaposi sarcoma herpes virus or human herpesvirus-8, which may coexist with HIV. A number of commercial test kits are available, with variable evidence of sensitivity, specificity, and utility. There is intense research on sophisticated but potentially facile handheld in-office devices for many disease markers. Challenges to their uptake require well-designed studies on their practical reliability and utility, with appropriate controls. A range of ethical, social, and political issues need to be addressed in such studies.


Assuntos
Infecções por HIV/diagnóstico , Doenças da Boca/diagnóstico , RNA Viral/análise , Saliva/virologia , Sarcoma de Kaposi/diagnóstico , Biomarcadores/análise , Grupos Focais , Infecções por HIV/complicações , HIV-1/isolamento & purificação , Herpesvirus Humano 8/isolamento & purificação , Humanos , Testes Imunológicos , Dispositivos Lab-On-A-Chip , Programas de Rastreamento/métodos , Doenças da Boca/complicações , Doenças da Boca/virologia , Neoplasias Bucais/complicações , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/virologia , Saliva/química , Sarcoma de Kaposi/complicações , Sarcoma de Kaposi/virologia , Sensibilidade e Especificidade
11.
Oral Dis ; 8 Suppl 2: 169-75, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12164652

RESUMO

Oral fluids are rarely a vehicle for HIV-1 infection in vivo, unlike other mucosal secretions. This unique property raises questions regarding (1) the molecular mechanisms responsible for the lack of salivary transmission, (2) the extent to which oral immunological responses mirror responses at other mucosal sites, (3) the use of promising salivary markers of HIV-1 disease progression, (4) the relationship between oral and blood viral loads, (5) cofactors that influence oro-genital transmission, and (6) the feasibility of oral-based antibody testing for HIV-1 diagnosis in the home. This paper discusses these questions and provides background summaries, findings from new studies, consensus opinions, practical relevance to developing countries, and suggestions for future research agenda on each of the key topics.


Assuntos
Infecções por HIV/fisiopatologia , HIV-1/fisiologia , Saliva/fisiologia , Anticorpos Antivirais/análise , Antígenos Virais/imunologia , Antivirais/farmacologia , Biomarcadores/análise , Países em Desenvolvimento , Progressão da Doença , Estudos de Viabilidade , Infecções por HIV/transmissão , HIV-1/imunologia , Humanos , Imunidade nas Mucosas/imunologia , Mucosa Bucal/imunologia , Kit de Reagentes para Diagnóstico , Saliva/química , Saliva/imunologia , Saliva/virologia , Proteínas e Peptídeos Salivares/imunologia , Comportamento Sexual , Carga Viral , Viremia/virologia
12.
J Pharm Sci ; 90(9): 1386-94, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11745791

RESUMO

Previous studies have shown that two classes of amphoteric surfactants, N-alkyl betaines and N-alkyl-N,N-dimethylamine oxides, exhibit pronounced antimicrobial activity in combination and have potential for use in a semisolid formulation for topical or vaginal delivery. In this work, several potential delivery systems were prepared and evaluated for antimicrobial activity and diffusional properties. A novel antimicrobial test for semisolids was proposed that determined the contact time needed to kill microorganisms. The unformulated agents in solution exhibited the faster kill within 60 min, followed by the hydroxyethylcellulose gel formulation in 90 min, and the poloxamer gel and a cream that required several hours. Diffusion from the dosage form utilized a Slide-A-Lyzer diffusion cassette with a 10,000 MWCO membrane with (14)C-labeled active species added to the aforementioned antimicrobial formulations. Diffusion of the individual betaine and amine oxide derivatives were tracked over time to determine the diffusion rates and profiles of the components in each formulation and in solution. The betaine derivative diffused up to three times faster than the amine oxide derivative within the first 2 h, but the amount diffused was approximately equivalent at 24 h. The formulations delayed release in the same rank order as the contact time kill analysis: hydroxyethylcellulose gel > poloxamer gel > cream.


Assuntos
Antibacterianos/farmacocinética , Betaína/farmacocinética , Dimetilaminas/farmacocinética , Fármacos Gastrointestinais/farmacocinética , Óxidos/farmacocinética , Antibacterianos/química , Betaína/química , Química Farmacêutica , Difusão , Dimetilaminas/química , Escherichia coli/efeitos dos fármacos , Excipientes/farmacocinética , Fármacos Gastrointestinais/química , Pomadas/farmacocinética , Óxidos/química , Soluções , Staphylococcus aureus/efeitos dos fármacos
13.
J Dent Res ; 80(6): 1550-4, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11499511

RESUMO

Saliva contains acidic proline-rich salivary proteins that are involved in the formation of the salivary pellicle coating supragingival tooth surfaces. However, human leukocyte elastase, arriving in gingival exudates from inflamed periodontal tissues, degrades the acidic proline-rich salivary proteins, preventing binding to hydroxylapatite surfaces. Here it is reported that high-molecular-weight non-immunoglobulin salivary agglutinin inhibited the proteolytic action of human leukocyte elastase on purified acidic proline-rich salivary proteins. Inhibition was eliminated with monoclonal antibody to a protein determinant on the salivary agglutinin. The addition of antibody against salivary agglutinin blocked the inhibitory effect of parotid saliva on exogenously applied human leukocyte elastase, allowing for the elastase-mediated digestion of the salivary acidic proline-rich salivary proteins. Salivary agglutinin, therefore, is a physiologically important inhibitor of human leukocyte elastase and is able to inhibit elastase-mediated digestion of salivary acidic proline-rich proteins.


Assuntos
Aglutininas/metabolismo , Elastase de Leucócito/antagonistas & inibidores , Peptídeos/metabolismo , Inibidores de Proteases/metabolismo , Proteínas e Peptídeos Salivares/metabolismo , Aglutininas/química , Aglutininas/farmacologia , Anticorpos Monoclonais , Reações Antígeno-Anticorpo , Película Dentária , Relação Dose-Resposta a Droga , Líquido do Sulco Gengival/enzimologia , Humanos , Imunoglobulina G , Peso Molecular , Periodontite/enzimologia , Domínios Proteicos Ricos em Prolina , Saliva/química , Proteínas Salivares Ricas em Prolina
14.
Fertil Steril ; 76(1): 189-95, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11438341

RESUMO

OBJECTIVE: To assess the use of magnetic resonance imaging (MRI) to determine the varying distribution of a vaginally placed gel over time and with different levels of patient activity. DESIGN: Prospectives interventional trial. SETTING: University medical center. PATIENT(S): One nulliparous volunteer with normal menstrual cycles and no gynecologic disease who underwent seven MRI scans of the pelvis. INTERVENTION(S): Five mL of a commercially available topical spermicide was mixed with gadolinium-chelate magnetic resonance contrast material and introduced with a standard applicator. T1-weighted three-dimensional MRI was done to assess the distribution of the gel. MAIN OUTCOME MEASURE(S): Gel thickness and distribution. RESULT(S): The initial bolus of gel was delivered into the upper portion of the vagina, above the urogenital diaphragm. Thereafter, it spread into the vaginal fornices and "flattened" to cover the lateral aspects of the vagina. Without ambulation, the majority of spread was confined to the upper vagina. With ambulation and longer elapsed time, the gel spread further in the upper vagina and into the lower vagina, and significant vaginal surface coverage increased significantly. CONCLUSION(S): Magnetic resonance imaging can be used to monitor the spread of vaginally placed products and to evaluate coverage of topical drugs used for prevention and treatment, including those used for HIV prophylaxis.


Assuntos
Imageamento por Ressonância Magnética , Espermicidas/administração & dosagem , Espermicidas/farmacocinética , Vagina/metabolismo , Administração Tópica , Feminino , Géis , Humanos , Estudos Prospectivos , Fatores de Tempo , Distribuição Tecidual , Caminhada
15.
Artigo em Inglês | MEDLINE | ID: mdl-11458246

RESUMO

OBJECTIVE: Whether oral lesions were associated with human immunodeficiency virus-type 1 (HIV-1) status in a cohort of pregnant Malawian women was studied. STUDY DESIGN: Six hundred thirty-eight women participated in a randomized prospective study at 3 prenatal clinics in a rural area of southern Malawi. Oral examinations, followed by collection of oral fluid specimens with an HIV-1 oral specimen collection device, were performed. The specimens were tested for antibodies against HIV-1. RESULTS: Sixty-one oral lesions were found in 60 participants. While traditional HIV-1 associated lesions were rare, benign migratory glossitis was unexpectedly common (6%). Oral hairy leukoplakia was significantly more common among women who were HIV-1 positive than among women who were HIV-1 negative. An HIV-1 prevalence rate of 21.8% was estimated among the women, with the highest rate of HIV-1 infection (34.1%) among women aged 25 to 29 years. CONCLUSION: Stratifying lesions showed a small number of oral hairy leukoplakia to be markers for HIV-1. A high seroprevalence was found in this rural cohort, but there were unexpectedly few oral lesions. The relatively few oral lesions diagnosed may indicate a recent infection with HIV.


Assuntos
Infecções por HIV/epidemiologia , HIV-1 , Doenças da Boca/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Saúde da População Rural/estatística & dados numéricos , Adulto , Fatores Etários , Análise de Variância , Distribuição de Qui-Quadrado , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática , Feminino , Glossite Migratória Benigna/epidemiologia , Anticorpos Anti-HIV/análise , Soronegatividade para HIV , Soropositividade para HIV/epidemiologia , Humanos , Leucoplasia Pilosa/epidemiologia , Malaui/epidemiologia , Paridade , Gravidez , Cuidado Pré-Natal , Prevalência , Estudos Prospectivos , Saliva/imunologia , Infecções Sexualmente Transmissíveis/epidemiologia , Estatística como Assunto , Tuberculose Pulmonar/epidemiologia
16.
Hum Reprod ; 16(6): 1151-4, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11387285

RESUMO

Topical, intravaginal microbicides and spermicides are greatly needed to prevent transmission of sexually transmitted diseases and/or unwanted pregnancies. The development of such compounds is a high research priority. The presumed method of action of existing, or novel, microbicides/spermicides is to provide a chemical barrier to the vaginal epithelium preventing exposure to micro-organisms. Other intravaginal products are used to treat vaginal bacteria of fungal infections. Little is known, however, about the actual or optimal initial distribution and subsequent spread of medications placed in the vagina. We describe a sensitive new technique to quantify the spread of a gel placed in the vagina using magnetic resonance imaging (MRI). Five millilitres of an over-the-counter spermicide containing Nonoxynol-9 was mixed with Gadolinium. MRI was used to quantify spread of the mixture 10 min after insertion with a standard applicator. We demonstrated contiguous spread of gel throughout the vagina. The coverage of material was thicker in the upper vagina than in the lower vagina. We also demonstrated, for the first time, that spermicidal compounds may migrate from the vaginal canal into the endocervix within 10 min of insertion. This finding suggests that topical microbicides/spermicides may act both in the vaginal canal and in the upper female genital tract.


Assuntos
Colo do Útero/metabolismo , Nonoxinol/farmacocinética , Espermicidas/farmacocinética , Vagina/metabolismo , Administração Intravaginal , Feminino , Gadolínio/administração & dosagem , Humanos , Cinética , Imageamento por Ressonância Magnética , Nonoxinol/administração & dosagem , Sensibilidade e Especificidade , Espermicidas/administração & dosagem
17.
Antimicrob Agents Chemother ; 44(9): 2514-7, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10952604

RESUMO

Alkyl betaines and alkyl dimethylamine oxides have been shown to have pronounced antimicrobial activity when used individually or in combination. Although several studies have been conducted with these compounds in combinations, only equimolar concentrations of the C(12)/C(12) and C(16)/C(14) chain lengths for the betaine and the amine oxide, respectively, have been investigated. This study investigates the antimicrobial activity of a wide range of chain lengths (C(8) to C(18)) for both the betaine and amine oxide and attempts to correlate their micelle-forming capabilities with their biological activity. A broth microdilution method was used to determine the MICs of these compounds singly and in various molar ratio combinations. Activity against both Staphylococcus aureus and Escherichia coli was investigated. Antimicrobial activity was found to increase with increasing chain length for both homologous series up to a point, exhibiting a cutoff effect at chain lengths of approximately 16 for betaine and 14 for amine oxide. Additionally, the C(18) oleyl derivative of both compounds exhibited activity in the same range as the peak alkyl compounds. Critical micelle concentrations were correlated with MICs, inferring that micellar activity may contribute to the cutoff effect in biological activity.


Assuntos
Antibacterianos/farmacologia , Betaína/farmacologia , Escherichia coli/efeitos dos fármacos , Óxidos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Betaína/análogos & derivados , Betaína/química , Estudos de Avaliação como Assunto , Humanos , Testes de Sensibilidade Microbiana , Óxidos/química , Especificidade da Espécie , Relação Estrutura-Atividade
18.
Antimicrob Agents Chemother ; 44(7): 1954-60, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10858360

RESUMO

A broad-spectrum vaginal microbicide must be effective against a variety of sexually transmitted disease pathogens and be minimally toxic to the cell types found within the vaginal epithelium, including vaginal keratinocytes. We assessed the sensitivity of primary human vaginal keratinocytes to potential topical vaginal microbicides nonoxynol-9 (N-9), C31G, and sodium dodecyl sulfate (SDS). Direct immunofluorescence and fluorescence-activated cell sorting analyses demonstrated that primary vaginal keratinocytes expressed epithelial cell-specific keratin proteins. Experiments that compared vaginal keratinocyte sensitivity to each agent during a continuous, 48-h exposure demonstrated that primary vaginal keratinocytes were almost five times more sensitive to N-9 than to either C31G or SDS. To evaluate the effect of multiple microbicide exposures on cell viability, primary vaginal keratinocytes were exposed to N-9, C31G, or SDS three times during a 78-h period. In these experiments, cells were considerably more sensitive to C31G than to N-9 or SDS at lower concentrations within the range tested. When agent concentrations were chosen to result in an endpoint of 25% viability after three daily exposures, each exposure decreased cell viability at the same constant rate. When time-dependent sensitivity during a continuous 48-h exposure was examined, exposure to C31G for 18 h resulted in losses in cell viability not caused by either N-9 or SDS until at least 24 to 48 h. Cumulatively, these results reveal important variations in time- and concentration-dependent sensitivity to N-9, C31G, or SDS within populations of primary human vaginal keratinocytes cultured in vitro. These investigations represent initial steps toward both in vitro modeling of the vaginal microenvironment and studies of factors that impact the in vivo efficacy of vaginal topical microbicides.


Assuntos
Betaína/análogos & derivados , Ácidos Graxos Insaturados/farmacologia , Queratinócitos/efeitos dos fármacos , Dodecilsulfato de Sódio/farmacologia , Tensoativos/farmacologia , Vagina/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Betaína/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Feminino , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Queratinas/metabolismo , Nonoxinol/farmacologia , Vagina/citologia
19.
Antiviral Res ; 43(3): 157-73, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10551374

RESUMO

A highly desirable approach to prevention of human immunodeficiency virus type 1 (HIV-1) transmission during sexual intercourse is the development of nontoxic, topical, broad spectrum microbicides effective against transmission of cell-associated and cell-free virus. Toward this end, the HIV-1 inactivation potential of surface active agents C31G and an alkyl sulfate, sodium dodecyl sulfate (SDS) was assessed. Because of its extensive use as a microbicidal agent, nonoxynol-9 (N-9) was used as a reference against which C31G and SDS were compared. Viral inactivation was measured using HIV-1 LTR-beta-galactosidase indicator cells (expressing CD4 or CD4/CCR5) derived from HeLa cells, a cell line of human cervical adenocarcinoma origin. In experiments which examined inactivation of cell-free HIV-1, C31G was generally more effective than N-9. Viral inactivation by SDS occurred at twice the concentration necessary to achieve similar levels of inactivation using either N-9 or C31G. Using HeLa and HeLa-derived cells in cytotoxicity studies, it was demonstrated that SDS is as much as 11 and five times less cytotoxic than N-9 or C31G, respectively, during 48 h of continuous exposure. SDS (unlike C31G and N-9) can inactivate non-enveloped viruses such as human papillomavirus (HPV) [Howett, M.K., Neely, E.B., Christensen, N.D., Wigdahl, B., Krebs, F.C., Malamud, D., Patrick, S.D., Pickel, M.D., Welsh, P.A., Reed, C.A., Ward, M.G., Budgeon, L.R., Kreider, J.W., 1999. A broad-spectrum microbicide with virucidal activity against sexually transmitted viruses. Antimicrob. Agents Chemother. 43(2), 314-321]. Since addition of SDS to C31G or N-9 may make the resulting microbicidal mixtures broadly effective against both enveloped and non-enveloped viruses, several surface active agent combinations were evaluated for their abilities to inactivate HIV-1. Addition of SDS to either C31G or N-9 resulted in mixtures that were only slightly less effective than equivalent concentrations of C31G or N-9 alone. To investigate inactivation of cell-associated infectivity, HIV-1 IIIB-infected SupT1 cells were treated with N-9, C31G, or SDS. Inactivation of cell-associated infectivity required higher microbicide concentrations than were needed for inactivation of cell-free virus. However, the relative activities of N-9, C31G, or SDS were similar to those seen in assays of inactivation using cell-free virus. These studies suggest that C31G and SDS may be attractive candidates for human trials as topical microbicides effective against HIV-1 transmission since both function at concentrations that provide effective viral inactivation with low levels of cytotoxicity. SDS microbicides (used alone or with other microbicides) may provide the added advantage of protection from HPV infection.


Assuntos
Fármacos Anti-HIV/farmacologia , Betaína/análogos & derivados , Ácidos Graxos Insaturados/farmacologia , HIV-1/efeitos dos fármacos , Nonoxinol/farmacologia , Dodecilsulfato de Sódio/farmacologia , Tensoativos/farmacologia , Fármacos Anti-HIV/administração & dosagem , Betaína/administração & dosagem , Betaína/farmacologia , Linhagem Celular , Interações Medicamentosas , Ácidos Graxos Insaturados/administração & dosagem , Células HeLa , Humanos , Linfócitos/citologia , Linfócitos/efeitos dos fármacos , Linfócitos/virologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/virologia , Dodecilsulfato de Sódio/administração & dosagem , Tensoativos/administração & dosagem , Fatores de Tempo
20.
Antimicrob Agents Chemother ; 43(2): 314-21, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9925525

RESUMO

Sodium dodecyl sulfate (SDS), an alkyl sulfate surfactant derived from an organic alcohol, possesses surfactant properties but also denatures and unfolds both monomeric and subunit proteins. In preliminary experiments, we demonstrated that SDS is a potent inactivator of herpes simplex virus type 2 and human immunodeficiency virus type 1 at concentrations comparable to those used for the surfactant nonoxynol-9. We hypothesized that SDS might be capable of denaturing the capsid proteins of nonenveloped viruses. In this report, we demonstrate inactivation of rabbit, bovine, and human papillomaviruses after brief treatment with dilute solutions of SDS. Effective concentrations were nontoxic to rabbit skin and to split-thickness grafts of human foreskin epithelium. This is the first report of a microbicidal surfactant that will inactivate papillomaviruses. We propose that SDS is now a candidate microbicide for formulation and testing with humans.


Assuntos
Antivirais/farmacologia , HIV-1/efeitos dos fármacos , Herpesvirus Humano 2/efeitos dos fármacos , Dodecilsulfato de Sódio/farmacologia , Tensoativos/farmacologia , Animais , Papillomavirus Bovino 1/efeitos dos fármacos , Células Cultivadas , Papillomavirus de Coelho Cottontail/efeitos dos fármacos , Células Epiteliais/patologia , Células Epiteliais/virologia , Humanos , Camundongos , Papillomaviridae/efeitos dos fármacos , Coelhos , Infecções Sexualmente Transmissíveis/virologia , Pele/patologia , Pele/virologia , Transplante Heterólogo
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