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Biomedical subjects

R Herrero

Publications and source records attributed to R Herrero.

At least 19 recordsLinked to original sources
PubMed2003

Role of paan chewing and dietary habits in cervical carcinoma in Chennai, India.

Non-viral factors contribute to human papillomavirus (HPV)-related cervical carcinogenesis. We investigated the role of paan chewing and dietary habits among 205 women with invasive cervical cancer (ICC) and 213 age-matched control women in Chennai, India. Odds ratios (OR) and 95% confidence intervals (CI) were computed by means of unconditional multiple regression, taking into account major correlates of ICC risk. Paan chewing showed a dose-dependent direct association with ICC (OR for >/=5 paan day(-1)=4.0; 95% CI 1.2-13.3). Among dietary habits, the highest vs lowest intake tertile for vegetables and fruit was associated with an OR of 0.5 (95% CI 0.2-1.0). Low education level and low body weight were also risk factors for ICC, but they did not account for the associations of paan chewing and low vegetable and fruit intake. In the analyses restricted to HPV-positive cases and controls, the inverse association with vegetable and fruit intake was confirmed. Conversely, the adverse influence of paan chewing on ICC risk seemed to be attributable to a higher prevalence of cervical HPV infection in women who chewed.

Adult↗
PubMed2003

Self-organized superlattice patterns with two slightly differing wave numbers.

We report on the observation of superlattices that occur spontaneously in a nonlinear optical system with O(2) symmetry. A secondary bifurcation from hexagons yields patterns formed by twelve wave vectors. Besides irregular patterns these may either be quasiperiodic patterns or superlattices built from two classes of wave vectors differing slightly in their length. Both classes of wave vectors stem from only one pattern-forming instability. The wave vectors fit on a hexagonal or a square grid. In the former case the set of wave vectors can be decomposed into two hexagonal triads, whereas in the case of the square grid squeezed triads occur.

Journal Article↗
PubMed2003

Smoking, alcohol, diet, dentition and sexual practices in the epidemiology of oral cancer in Poland.

The effect of smoking, drinking, diet, dental care and sexual habits on the risk of oral and pharyngeal cancer was investigated in a case-control study conducted in Warsaw, Poland. The study comprised 122 patients (including 44 females) aged 23-80 years with histologically confirmed cancer of oral cavity and pharynx. Controls were 124 subjects (including 52 females) admitted to the hospital for different non-neoplastic conditions unrelated to tobacco and alcohol consumption, with frequency matched to cases by age and sex. Smoking and drinking were strongly associated with an increased risk of oral cancer. Among consumers of both products, risks of oral cancer tended to combine in a multiplicative fashion and were increased more than 14-fold among those who consumed more than 15 cigarettes and seven or more drinks per day. Cessation of smoking was associated with reduced risk of this cancer. The risks varied by type of cigarettes smoked, being lower among those consuming filtered cigarettes only (OR = 1.6) than nonfilter (OR = 6.5) or mixed (OR = 4.2) cigarettes. High fruit intake was associated with significantly decreased risk (OR = 0.4) with the strongest significant inverse association found for fruit juices and citrus fruits ( < 0.01). After adjustment for tobacco smoking and alcohol drinking, poor dentition as evidenced by missing teeth, frequency of dental check-ups and frequency of teeth brushing emerged as a strong risk factor. Number of missing teeth and frequency of dental check-ups and frequency of tooth brushing showed increased ORs of 9.8, 11.9 and 3.2, respectively. Denture wearing did not affect oral cancer risk. No differences were detected in sexual practices (including oral sex and intercourse with prostitutes). In terms of attributable risk, smoking accounted for 57% of oral cancer cases in Poland, alcohol for 31% and low fruit intake for 12%. Attributable risks for low frequency of tooth brushing and dental check-ups were 56% and 47%, respectively. In conclusion, smoking and drinking cessation and increase of fresh fruit intake are likely to be effective preventive measures against oral cancer. These findings indicate also that poor oral hygiene may be an independent risk factor.

Adult↗
PubMed2003

Oral and oropharyngeal cancer in Spain: influence of dietary patterns.

Cancer of the oral cavity and oropharynx is a major public health problem in Spain. Tobacco and alcohol have been identified as the two major risk factors for oral cancer in most western populations. Other risk factors include diets low in fruits and vegetables, but the impact of dietary habits on the risk of these cancers has never been assessed in Spain. The objective of this study was to elucidate the role of dietary habits in oral and oropharyngeal cancer, a multicentric case-control study was conducted in three areas of Spain (Barcelona, Granada and Sevilla) between 1996 and 1999. Cases were 375 patients (71 women), with incident, histologically confirmed cancer of the oral cavity or oropharynx, and controls were 375 subjects (71 women) admitted to hospitals for conditions unrelated to smoking or alcohol drinking. Data were analysed using multivariate logistic regression procedures. After allowance for education, tobacco and alcohol use, a significant inverse association with the risk of oral and oropharyngeal cancer was found for total consumption of total green vegetables (OR 0.54, 95% CI = 0.34-0.87) and total fruit (OR 0.52, 95% CI = 0.34-0.79) with significant trends in risk. We found that the protective effect of each of these food items was consistently larger among current smokers and among heavy alcohol drinkers, following a multiplicative effect model. In conclusion, this study provides further support to the beneficial effect of high intake of vegetables and fruits on the risk of developing cancers of the oral cavity and oropharynx in Spain, particularly among current smokers and heavy alcohol drinkers.

Adult↗
PubMed2003

Oral cancer in Southern India: the influence of body size, diet, infections and sexual practices.

Between 1996 and 1999, we carried out a study in Southern India on risk factors for oral cancer. The study included 591 incident cases of cancer of the oral cavity (282 women) and 582 hospital controls (290 women). Height was unrelated to oral cancer risk. Body mass index (weight in kilograms/height in metres squared) was inversely associated with risk (P for trend<0.001). Paan chewers with low BMI were at particularly high risk. Risk was increased among subjects consuming meat (odds ratio (OR) 1.54, 95% confidence interval (CI) 1.00-2.37), ham and salami (OR 4.40, 95% CI 2.88-6.71) two or more times per week. Frequent consumption of fish, eggs, raw green vegetables, cruciferous vegetables, carrots, pulses, apples or pears, citrus fruit, and overall consumption of vegetables and fruit decreased oral cancer risk (P for trend for each of these items less than or equal to 0.001). The risk associated with low consumption of vegetables was higher among smokers than among non-smokers. Men, but not women, who practised oral sex had an increased oral cancer risk (OR 3.14, 95% CI 1.15-8.63). Women with more than one sexual partner during life were at increased oral cancer risk (OR 9.93, 95% CI 1.57-62.9).

Adolescent↗
PubMed2002

Phase synchronization in bidirectionally coupled optothermal devices.

We present the experimental observation of phase synchronization transitions in the bidirectional coupling of chaotic and nonchaotic oscillators. A variety of transitions are characterized and compared to numerical simulations of a time delayed model. The characteristic 2pi phase jumps usually appear during the transitions, specially in those clearly associated with a saddle-node bifurcation. The study is done with pairs of optothermal oscillators linearly coupled by heat transfer.

Journal Article↗
PubMed2001

Human leukocyte antigen class I and II alleles and risk of cervical neoplasia: results from a population-based study in Costa Rica.

To examine human leukocyte antigen (HLA) involvement in the development of all grades of cervical neoplasia, a nested case-control study of 10,077 women in Guanacaste, Costa Rica, was conducted. Participants had invasive cervical cancer, high-grade squamous intraepithelial lesions (HSILs; n=166), or low-grade squamous intraepithelial lesions (LSILs); were positive for human papillomavirus (HPV) with no evidence of cervical neoplasia (n=320); or were HPV negative with no evidence of cervical neoplasia but with a history of high-risk sexual behavior (n=173). Compared with women who were HPV negative, women with HLA-DRB1*1301 were associated with decreased risk for cancer/HSILs (odds ratio [OR], 0.4; 95% confidence interval [CI], 0.2-0.7) and for LSILs/HPV (OR, 0.6; 95% CI, 0.3-0.9). Women with both HLA-B*07 and HLA-DQB1*0302 had an 8.2-fold increased risk for cancer/HSILs (95% CI, 1.8-37.2) and a 5.3-fold increased risk for LSILs/HPV (95% CI, 1.2-23.7). These results support the hypothesis that multiple risk alleles are needed in order to increase risk for cervical neoplasia, but a single protective allele may be sufficient for protection.

Alleles↗
PubMed2001

Risk factors for cancer of the oral cavity and oro-pharynx in Cuba.

In terms of worldwide levels, Cuba has an intermediate incidence of cancer of the oral cavity and oro-pharynx. We studied 200 cases of cancer of the oral cavity and pharynx, of whom 57 women (median age = 64) and 200 hospital controls, frequency matched with cases by age and sex, in relation to smoking and drinking history, intake of 25 foods or food groups, indicators of oral hygiene and sexual activity, and history of sexually transmitted diseases. Odds ratios (OR) and 95% confidence intervals (CI) were obtained from unconditional multiple logistic regressions and adjusted for age, sex, area of residence, education, and smoking and drinking habits. In the multivariate model, high educational level and white-collar occupation, but not white race, were associated with halving of oral cancer risk. Smoking > or =30 cigarettes per day showed an OR of 20.8 (95% CI: 8.9-48.3), similar to smoking > or =4 cigars daily (OR = 20.5). Drinking > or = 70 alcoholic drinks per week showed an OR of 5.7 (95% CI: 1.8-18.5). Hard liquors were by far the largest source of alcohol. Increased risk was associated with the highest tertile of intake for maize (OR = 1.9), meat (OR = 2.2) and ham and salami (OR = 2.0), whereas high fruit intake was associated with significantly decreased risk (OR = 0.4). Among indicators of dental care, number of missing teeth and poor general oral condition at oral inspection showed ORs of 2.7 and 2.6, respectively. Number of sexual partners, marriages or contacts with prostitutes, practice of oral sex and history of various sexually transmitted diseases, including genital warts, were not associated with oral cancer risk. 82% of oral cancer cases in Cuba were attributable to tobacco smoking, 19% to smoking cigars or pipe only. The fractions attributable to alcohol drinking (7%) and low fruit intake (11%) were more modest. Thus, decreases in cigarette and cigar smoking are at present the key to oral cancer prevention in Cuba.

Adult↗
PubMed2001

HPV co-factors related to the development of cervical cancer: results from a population-based study in Costa Rica.

We examined factors associated with high-grade squamous intraepithelial lesions (HSIL) and cervical cancer among human papillomavirus (HPV)-infected women in a prevalent case-control study conducted within a population-based cohort of 10 077 women in Costa Rica. We compared 146 women with HPV-positive HSIL or cancer (HSIL/CA) against 843 HPV-positive women without evidence of HSIL/CA. Subjects completed a risk factor questionnaire. We evaluated the associations between exposures and HSIL/CA among women positive for any HPV and restricted to those positive for high-risk HPV types. Risk of HSIL/CA increased with increasing number of live births (P(trend)= 0.04). Women who smoked 6+ cigarettes/day had a RR for HSIL/CA of 2.7 (95% CI = 1.1-6.7) compared to non-smokers. Current use of barrier contraceptives was associated with a reduction in risk of HSIL/CA (RR = 0.39; 95% CI = 0.16-0.96). Sexual behaviour and a self-reported history of sexually transmitted diseases (STDs) other than HPV were not associated with HSIL/CA. Oral contraceptive use was associated with HSIL/CA among women with <3 pregnancies. Effects were similar in analysis restricted to women positive for high-risk HPV types. Among women positive for high-risk HPV types, 44% of HSIL/CA could be attributed to multiparity (>/=3 pregnancies) and/or smoking. Among HPV-positive women, multiparity and smoking are risk factors for HSIL/CA. Oral contraceptive use may be associated with HSIL/CA in subgroups of women.

Adolescent↗
PubMed2001

Epidemiology of HPV infection among Mexican women with normal cervical cytology.

Cervical cancer is caused by human papillomavirus (HPV) and is the most common cancer among Mexican women, but no population-based studies have reported the prevalence and determinants of HPV infection in Mexico. A population-based study was carried out between 1996 and 1999, based on an age-stratified random sample of 1,340 women with normal cytologic diagnoses from 33 municipalities of Morelos State, Mexico. The prevalence of cervical HPV DNA was determined by reverse line blot strip assay to detect 17 cancer-associated and 10 non-cancer-associated HPV types. Two peaks of HPV DNA prevalence were observed. A first peak of 16.7% was observed in the age group under 25 years. HPV DNA prevalence declined to 3.7% in the age group 35-44 years, then increased progressively to 23% among women 65 years and older. Cancer-associated HPV types were the most common in all age groups; non-cancer-associated HPV types were rare in the young and became more common linearly with age. Twenty-four types of HPV were detected; HPV 16, HPV 53, HPV 31 and HPV 18 were the most common, but none was present in more than 1.7% of subjects. The main determinant of infection with both cancer-associated and non-cancer-associated HPV types was the number of sexual partners in all age groups. Less-educated women were at an increased risk of infection with cancer-associated but not with non-cancer-associated HPV types; low socioeconomic status was associated with detection of non-cancer-associated HPV types. Among young women an increasing number of pregnancies was associated with lower HPV detection and among older women low socioeconomic status was related to increased HPV detection, particularly for the age group 35-54 years. Among women with cancer-associated HPV types, there was a higher intensity of polymerase chain reaction signal in younger than in older age groups (p < 0.001). We present additional evidence for the sexually transmitted nature of HPV infection, regardless of age group and HPV type. We confirm previous findings of a second peak of high-risk HPV infections in postmenopausal women, in this case with a clear predominance of cancer-associated HPV types. In populations with this pattern, which can be related to reactivation of latent HPV infections or high previous exposure in older women, screening with HPV testing can have a reduced specificity among older women if proper cut-off points for HPV positivity are not used. Longitudinal studies of immune responses to HPV infection in different age groups are warranted.

Adult↗
PubMed2001

Absence of association between HPV DNA, TP53 codon 72 polymorphism, and risk of oesophageal cancer in a high-risk area of China.

We analyzed TP53 codon 72 polymorphism, HPV DNA in 32 subjects with oesophageal cancer and 57 healthy subjects with normal oesophageal cytology from an area of China with a high prevalence for this cancer (Linxian County, Henan Province). The frequency of the proline allele (0.63) was significantly higher in the Chinese population than in most European or American populations. No significant association was found between TP53 codon 72 genotype and cancer. We also found a low prevalence of HPV DNA (6.7%) in both cancer cases and healthy subjects. Our findings do not support the association between risk of oesophageal cancer, human papilloma virus infection, and TP53 codon 72 polymorphism in a Chinese population at high risk of oesophageal cancer.

Adult↗
PubMed2001

Adeno-associated virus seropositivity and HPV-induced cervical cancer in Spain and Colombia.

Extensive experimental and limited epidemiologic data suggest that adeno-associated viruses (AAV) can have antioncogenic activity and may be protective factors for the development of cervical cancer. To examine the association between AAV-2 IgG antibodies and cervical neoplasia in Spain and Colombia, we tested for AAV-2 antibodies using an ELISA assay for 109 women with invasive cervical cancer, 100 population-based controls age-matched to the invasive cases, 77 women with carcinoma in situ (CIN III) and 100 clinic-based controls age-matched to the CIN III cases. Human papillomavirus (HPV) DNA was detected in cervical exfoliated cells by polymerase chain reaction using HPV-L1 and GP5+/6+ consensus primers. The prevalence of AAV-2 antibody titers >100 was significantly lower in invasive cervical cancer cases than control participants. When comparing women with invasive cancer with controls or with CIN III cases, a pattern of decreasing cervical cancer risk with increasing AAV-2 titers was observed. Elevated AAV antibody titers (>100) were inversely associated with invasive cervical cancer (OR 0.3; 95% CI 0.1-0.7), although results were not statistically significant after controlling for HPV (OR 0.4; 95% CI 0.1-1.6). In contrast, AAV-2 antibodies were not significantly associated with the risk of CIN III (OR 1.4; 95% CI 0.3-6.8). These results provide supportive evidence that AAV infection may be a protective factor for the development of invasive cervical cancer. Alternatively, the lower AAV-2 seroprevalence in invasive cervical cancer cases may be due to an immunosuppressive effect of cervical cancer on AAV antibody response. To investigate whether a direct viral interaction is occurring, future studies should aim to resolve at what frequency AAV is found in the genital tract and to clarify further whether AAV may infect the same HPV-positive cells in the cervix.

Adult↗
PubMed2001

Prevalence and risk factors for herpes simplex virus type 2 infection among middle-age women in Brazil and the Philippines.

BACKGROUND: Data comparing type-specific herpes simplex virus type 2 (HSV-2) seroprevalence and risk factors between comparable populations are largely unavailable, particularly from less-developed countries. GOAL: To examine the seroprevalence of HSV-2 infection and the risk factors for this infection among women in São Paulo, Brazil, and Manila, the Philippines. STUDY DESIGN: Altogether, 552 middle-aged women participating as control subjects in two cervical cancer studies were screened for type-specific HSV-2 antibodies. RESULTS: Herpes simplex virus type 2 seroprevalence was higher in Brazil (42%) than in the Philippines (9.2%). The mean ages of Brazilian (n = 181) and Filipino (n = 371) women were 52.4 and 46.6 years, respectively. Brazilian participants had more lifetime sexual partners, less education, and more often a husband with other sexual partners than Filipino women. Herpes simplex virus type 2 was independently associated with younger age at first intercourse in both countries. More than one lifetime sexual partner, a husband with other sexual partners, urban/semi-urban residence, and no history of condom use were HSV-2 risk factors in Brazil, but not in the Philippines, where long-term hormonal contraceptive use was associated with increased risk. CONCLUSIONS: The higher HSV-2 seroprevalence in Brazil than in the Philippines may be explained largely by differences in the sexual behavior of women and their husbands. Herpes simplex virus type 2 seroprevalence data may be used as a marker of past sexual behavior for the direct comparison of different population groups.

Antibodies, Viral↗
PubMed2001

High prevalence of human papillomavirus infection in Mexican males: comparative study of penile-urethral swabs and urine samples.

BACKGROUND: Although extensive information has been gathered about the prevalence and determinants of human papillomavirus infection among women, little is known about the prevalence and natural history of this infection among males. GOAL: To investigate the potential usefulness of urine specimens to assess the presence of genital human papillomavirus DNA infection. STUDY DESIGN: The authors conducted a study of 120 healthy men from Cuernavaca, Mexico. A urine specimen and urethral and coronal sulcus swab samples were collected and tested for human papillomavirus using the GP5+/6+ polymerase chain reaction enzyme immunoassay method. RESULTS: In 95% of the urethral-coronal sulcus samples, the beta-globin gene was detectable, indicating adequacy of the specimen for DNA amplification; however, only 14% of the urine specimens had detectable beta-globin. Removal of inhibitors by DNA purification in a sample of subjects produced beta-globin amplification, but no increase in human papillomavirus DNA positivity was detected. Human papillomavirus DNA was not detectable in penile-urethral swab samples in any of the subjects who reported not having engaged in sexual activity but was present in 43% of men who reported sexual activity, a strong indication of the sexual transmission of human papillomavirus. CONCLUSIONS: Human papillomavirus is a common sexually transmitted infection among Mexican males, and urine sample specimens cannot adequately detect the presence of this infection in males.

Adolescent↗