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1.
Nat Med ; 4(5): 610-4, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9585237

RESUMEN

A novel strategy for anti-viral intervention of hepatitis B virus (HBV) through the disruption of the proper folding and transport of the hepadnavirus glycoproteins is described. Laboratory reared woodchucks chronically infected with woodchuck hepatitis virus (WHV) were treated with N-nonyl-deoxynojirimycin (N-nonyl-DNJ), an inhibitor of the endoplasmic reticulum (ER) alpha-glucosidases. The woodchucks experienced significant dose dependent decreases in enveloped WHV, resulting in undetectable amounts in some cases. The reduction in viremia correlated with the levels of hyperglucosylated glycan in the serum of treated animals. This correlation supports the mechanism of action associated with the drug and highlights the extreme sensitivity of the virus to this type of glycan inhibitor. At N-nonyl-DNJ concentrations that prevented WHV secretion, the glycosylation of most serum glycoproteins appeared unaffected, suggesting great selectivity for this class of therapeutics. Indeed, this may account for the low toxicity of the compound over the treatment period. We provide the first evidence that glucosidase inhibitors can be used in vivo to alter specific steps in the N-linked glycosylation pathway and that this inhibition has anti-viral effects.


Asunto(s)
1-Desoxinojirimicina/análogos & derivados , Antivirales/uso terapéutico , Inhibidores de Glicósido Hidrolasas , Virus de la Hepatitis B de la Marmota/efectos de los fármacos , Hepatitis B Crónica/veterinaria , Enfermedades de los Roedores/terapia , 1-Desoxinojirimicina/uso terapéutico , Animales , Transporte Biológico/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Retículo Endoplásmico/enzimología , Glucósidos/sangre , Glicosilación , Hepatitis B Crónica/terapia , Manósidos/sangre , Marmota , Oligosacáridos/sangre , Pliegue de Proteína , Replicación Viral/efectos de los fármacos
2.
Adv Cancer Res ; 134: 85-116, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28110657

RESUMEN

Glycosylated proteins account for a majority of the posttranslation modifications of cell surface, secreted, and circulating proteins. Within the tumor microenvironment, the presence of immune cells, extracellular matrix proteins, cell surface receptors, and interactions between stroma and tumor cells are all processes mediated by glycan binding and recognition reactions. Changes in glycosylation during tumorigenesis are well documented to occur and affect all of these associated adhesion and regulatory functions. A MALDI imaging mass spectrometry (MALDI-IMS) workflow for profiling N-linked glycan distributions in fresh/frozen tissues and formalin-fixed paraffin-embedded tissues has recently been developed. The key to the approach is the application of a molecular coating of peptide-N-glycosidase to tissues, an enzyme that cleaves asparagine-linked glycans from their protein carrier. The released N-linked glycans can then be analyzed by MALDI-IMS directly on tissue. Generally 40 or more individual glycan structures are routinely detected, and when combined with histopathology localizations, tumor-specific glycans are readily grouped relative to nontumor regions and other structural features. This technique is a recent development and new approach in glycobiology and mass spectrometry imaging research methodology; thus, potential uses such as tumor-specific glycan biomarker panels and other applications are discussed.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Procesamiento de Imagen Asistido por Computador/métodos , Imagen Molecular/métodos , Neoplasias/patología , Polisacáridos/metabolismo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Animales , Glicosilación , Humanos , Neoplasias/metabolismo
3.
Int J Cardiol ; 63(2): 165-73, 1998 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-9510491

RESUMEN

OBJECTIVE: To measure the prevalence of hypertension and age-specific blood pressure in urban populations from five Indian cities. Cross-sectional surveys were conducted in six-twenty urban streets in different cities from five different corners of India, using similar methods of sample selection and criteria. There were 3212 randomly selected women from Moradabad (n=902), Trivandrum (n=760), Calcutta (n=365), Nagpur (n=405) and Bombay (n=780), aged 25-64 years, inclusive. Evaluation was by a physician and a dietitian, an administered questionnaire, a physical examination and using a sphygmomanometer. The diagnosis of hypertension was based on old World Health Organisation criteria and new World Health Organisation/International Society of Hypertension criteria. The prevalence of hypertension (>140/90 mm Hg) was significantly (P<0.01) high in Trivandrum, South India (30.7%), and Bombay, West India (28.0%), compared to Moradabad, which is in northern India (22.6%), Nagpur, in central India (24.2%), and Calcutta, in east India (19.1%). Mean systolic and diastolic blood pressures were significantly higher in Trivandrum and Bombay compared to the other three cities. The overall prevalence of hypertension was 25.6% (n=823) and isolated diastolic hypertension was the most common form of hypertension (50.5%, n=1506) in the five Indian cities. According to old criteria, the overall prevalence of hypertension (>160/95 mm Hg) was 14.8% (n=481). Multivariate logistic regression analysis on pooled data from the five cities, after adjustment for age, showed that age (odds ratio 1.16), body mass index (1.68) and obesity were strongly associated with hypertension. A sedentary lifestyle and salt intake were weakly associated and alcohol intake was not a factor with these women.


Asunto(s)
Presión Sanguínea/fisiología , Hipertensión/epidemiología , Adulto , Distribución por Edad , Intervalos de Confianza , Estudios Transversales , Femenino , Conocimientos, Actitudes y Práctica en Salud , Encuestas Epidemiológicas , Humanos , Hipertensión/diagnóstico , Hipertensión/fisiopatología , India/epidemiología , Estilo de Vida , Modelos Logísticos , Persona de Mediana Edad , Análisis Multivariante , Obesidad/epidemiología , Prevalencia , Distribución Aleatoria , Factores de Riesgo , Muestreo
4.
Int J Cardiol ; 69(2): 139-47, 1999 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-10549837

RESUMEN

OBJECTIVE: To find out the association between social class and coronary risk factors in women. DESIGN AND SETTING: Cross-sectional surveys were conducted in six-twelve urban streets in each of five cities from various regions of India following a common study protocol and criteria of diagnosis. SUBJECTS AND METHODS: We randomly selected 3257 women, aged 25-64 years inclusive, from the cities of Moradabad (n=902), Trivandrum (n=760) Calcutta (n=410), Nagpur (n=405) and Bombay (n=780). Evaluation was by questionnaires validated at Moradabad. All subjects, after pooling of data, were divided into social class 1 (n=985), social class 2 (n=790), social class 3 (n=674), social class 4 (n=602) and social class 5 (n=206), based on various attributes of socioeconomic status. RESULTS: The prevalence of hypertension, diabetes mellitus, family history of coronary disease, obesity, central obesity and sedentary lifestyle were significantly associated with higher social classes and tobacco consumption was not associated with social class. Oral contraceptive intake and postmenopausal status were also more common among higher social classes, which may be due to more education and a longer lifespan among the higher social classes, respectively. Mean total cholesterol, high density lipoprotein cholesterol, systolic and diastolic blood pressure, mean body mass index and waist-hip ratio showed significant association with higher social classes. Mean age, body weight, body mass index, waist-hip ratio, systolic and diastolic blood pressure, total cholesterol and 2-h blood glucose were significantly positively correlated with social class, as assessed by Spearman's rank correlation. Higher social classes 1-3 were more common in Trivandrum and Bombay than in Moradabad. The prevalence of hypertension, diabetes mellitus and being overweight (body mass index >25 kg/m2) were also more common in Trivandrum and Bombay compared to Moradabad. Undernutrition was negatively associated with higher social classes and was more common in Moradabad and Nagpur than Trivandrum. CONCLUSIONS: Higher social classes among Indian urban women have a higher prevalence of coronary risk factors, hypertension, diabetes mellitus, being overweight, central obesity, sedentary lifestyle, family history of coronary disease, oral contraceptive intake and postmenopausal status. Mean concentrations of total and high density lipoprotein cholesterol were also significantly associated with higher social classes.


Asunto(s)
Enfermedad Coronaria/epidemiología , Clase Social , Adulto , Colesterol/sangre , Estudios Transversales , Diabetes Mellitus/epidemiología , Femenino , Encuestas Epidemiológicas , Humanos , Hipertensión/epidemiología , India/epidemiología , Persona de Mediana Edad , Estado Nutricional , Obesidad/epidemiología , Prevalencia , Factores de Riesgo
5.
Proc Natl Acad Sci U S A ; 96(21): 11878-82, 1999 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-10518544

RESUMEN

One function of N-linked glycans is to assist in the folding of glycoproteins by mediating interactions of the lectin-like chaperone proteins calnexin and calreticulin with nascent glycoproteins. These interactions can be prevented by inhibitors of the alpha-glucosidases, such as N-butyl-deoxynojirimycin (NB-DNJ) and N-nonyl-DNJ (NN-DNJ), and this causes some proteins to be misfolded and retained within the endoplasmic reticulum (ER). We have shown previously that the NN-DNJ-induced misfolding of one of the hepatitis B virus (HBV) envelope glycoproteins prevents the formation and secretion of virus in vitro and that this inhibitor alters glycosylation and reduces the viral levels in an animal model of chronic HBV infection. This led us to investigate the effect of glucosidase inhibitors on another ER-budding virus, bovine viral diarrhea virus, a tissue culture surrogate of human hepatitis C virus (HCV). Here we show that in MDBK cells alpha-glucosidase inhibitors prevented the formation and secretion of infectious bovine viral diarrhea virus. Data also are presented showing that NN-DNJ, compared with NB-DNJ, exhibits a prolonged retention in liver in vivo. Because viral secretion is selectively hypersensitive to glucosidase inhibition relative to the secretion of cellular proteins, the possibility that glucosidase inhibitors could be used as broad-based antiviral hepatitis agents is discussed. A single drug against HBV, HCV, and, possibly, HDV, which together chronically infect more than 400 million people worldwide, would be of great therapeutic value.


Asunto(s)
Antivirales/metabolismo , Virus de la Diarrea Viral Bovina/metabolismo , Diseño de Fármacos , Hepacivirus/metabolismo , Pestivirus/metabolismo , 1-Desoxinojirimicina/farmacología , Animales , Bovinos , Supervivencia Celular , Retículo Endoplásmico/virología , Inhibidores de Glicósido Hidrolasas , Hepacivirus/efectos de los fármacos , Humanos , Polisacáridos/metabolismo , Distribución Tisular
6.
Asia Pac J Clin Nutr ; 9(4): 298-302, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24394506

RESUMEN

The association between social classes, food intake and coronary risk factors was determined. Cross-sectional surveys were conducted in 6-12 urban streets in each of five cities, each one from five different regions of India using similar methods of dietary intakes and criteria of diagnosis. We randomly selected 3257 women aged 25-64 years inclusive, from Moradabad (n = 902), Trivandrum (n = 760), Calcutta (n = 410), Nagpur (n = 405) and Bombay (n = 780). All subjects, after pooling of data, were divided into social class 1 (n = 985), class 2 (n = 790), class 3 (n = 774), class 4 (n = 602) and class 5 (n = 206) based on various attributes of socioeconomic status. Social class 1 was the highest and 5 was the lowest social class. Social classes 1-3 had greater intake of pro-atherogenic foods; total visible fat, milk and milk products, meat and eggs, as well as sugar and confectionery, compared to social classes 4 and 5. The consumption of wheat, rice, millets, fruits, vegetables and legume/total visible fat ratio were inversely associated with social class. Mean body mass index (BMI), obesity, overweight, central obesity and sedentary lifestyle were also significantly more common among subjects from higher social classes. Spearman's rank correlation showed that bodyweight, BMI, wheat, rice, millets, total visible fat, milk and milk products, meat, eggs, sugar and jaggery intakes were significantly correlated with social class. Social class 5 subjects had a lower intake of all foods and a lower BMI, suggestive of a higher rate of undernutrition among them. The findings indicate that the consumption of pro-atherogenic foods and other coronary risk factors are more common in higher social classes compared to lower social classes.

7.
J Cardiovasc Risk ; 5(2): 73-7, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9821058

RESUMEN

OBJECTIVE: To study the prevalence of central obesity and age-specific waist:hip ratio of urban women from five Indian cities. DESIGN AND SETTING: Cross-sectional surveys were conducted in 6-12 urban streets in different parts of India using similar methods of sample selection and criteria of diagnosis. SUBJECTS AND METHODS: We randomly selected 3212 women, aged 25-64 years, from Moradabad (n = 902), Trivandrum (n = 760), Calcutta (n = 365), Nagpur (n = 405), and Bombay (n = 780). Evaluation was by a questionnaire administered by a physician and a dietician, a physical examination, and anthropometric measurements. RESULTS: The overall prevalence of central obesity among the total number of women was 55.0%, with the highest prevalence in Calcutta (62.2%) and the lowest in Bombay (47.4%). Waist:hip ratio was 0.85 +/- 0.13 (mean +/- SD) with the highest ratio for women in Calcutta (0.87 +/- 0.12) and the lowest for women in Moradabad (0.84 +/- 0.16). After pooling of data from all five cities, multivariate logistic regression analysis showed that, regardless of age, body mass index (> 23 kg/m2; odds ratio 1.12), sedentary lifestyle (odds ratio 2.51), and family history of obesity (odds ratio 2.15) were strongly associated with central obesity. Excess intake of fat was weakly associated with central obesity but age was not a risk factor for central obesity, although the prevalence was highest among those aged over 55 years in Moradabad, Calcutta, and Nagpur. CONCLUSIONS: The overall prevalence of central obesity among the urban women of India has increased, more so in Calcutta and Trivandrum. Body mass index, sedentary lifestyle, and family history of excess intake of fat were significant risk factors for central obesity.


Asunto(s)
Constitución Corporal , Obesidad/epidemiología , Adulto , Factores de Edad , Grasas de la Dieta , Femenino , Humanos , India/epidemiología , Estilo de Vida , Persona de Mediana Edad , Obesidad/patología , Prevalencia , Factores de Riesgo , Población Urbana
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