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L Ortega

Publications and source records attributed to L Ortega.

At least 37 records · Page 2Linked to original sources
PubMed2001

What's being used at home: a household pesticide survey.

OBJECTIVE: Since very little is known about the health effects that household pesticides have on children, we conducted this survey to identify what pesticides are being used in the home, where they are being used and stored, and what methods are used for their disposal. METHODS: In the spring of 1999 we conducted a survey in a community in the state of Arizona, in the United States of America, on the border with Mexico. To be eligible to participate in the survey, households had to have used a pesticide in the 6 mo prior to the survey and to have at least one child under the age of 10 years. We gathered general information on pesticide usage, storage, and disposal, in addition to specific information about each of the pesticides currently being used and/or stored in the home. RESULTS: In the 107 households surveyed, we found 148 pesticide products, for a mean of 1.4 per household. Half of the pesticides were stored less than 4 feet (1.22 m) from the ground, at a level a child could reach. Seventy percent of all the pesticides were stored inside the home, with the kitchen being the storage room most often mentioned. The kitchen was also the room where most of the pesticides were used, with 69% of the respondents saying they had used at least one pesticide there. CONCLUSIONS: From our research we conclude that it will be important to continue to investigate all avenues of pesticide exposure in order to fully evaluate childhood exposures. Understanding household pesticide use and developing a model of exposure will help in this process. Profiles of the use, storage, and disposal of products will also guide the development of effective education and poison prevention programs in the community.

Child↗
PubMed2001

Design and results of the USA-Mexico border human papillomavirus (HPV), cervical dysplasia, and Chlamydia trachomatis study.

OBJECTIVE: Mexico has one of the highest mortality rates of invasive cervical cancer in the world. This is particularly true for the states in northern Mexico that border on the United States of America. In addition, Hispanics in the United States have higher rates than do non-Hispanics in the country. Therefore, a binational team was formed to focus on this problem and to determine the risk factors and prevalence of cervical dysplasia and human papillomavirus (HPV) infection, the sexually transmitted disease (STD) known to cause cervical cancer. Chlamydia trachomatis infection, a common STD and potential HPV cofactor, was also assessed. METHODS: Research was conducted in 1997 and 1998 in the border region of two states, Arizona in the United States and Sonora in Mexico, applying a cross-sectional study of women attending clinics for routine gynecologic care. Clinical measurements included Pap smears, HPV infection by both polymerase chain reaction (PCR) and Hybrid Capture (HC), and C. trachomatis status by HC and enzyme-linked immunoassay (EIA). A total of 2,436 women were enrolled (mean age 33.3 years +/- 10.3 years). RESULTS: The overall prevalence of abnormal cytology was 9.3%, with a significant difference in the prevalence in Mexico (11.4%) vs. the United States (6.6%). Of the participants, 14.5% of them tested positive for HPV by PCR, with no significant difference between the two countries, in spite of a lower behavioral risk profile for the Mexican women. Overall prevalence of C. trachomatis was found to be greater by HC than by EIA (8.2% vs. 3.0%), and in Mexico higher by both methods. CONCLUSIONS: An important accomplishment of the project was the implementation of a quality control program for Pap smear collection, which resulted in a significant reduction in inadequate smears in Mexico. Despite numerous potential logistical barriers, the binational team successfully conducted a large-scale study in the border area and developed an infrastructure for future research.

Adolescent↗
PubMed2001

Human papillomavirus infection at the United States-Mexico border: implications for cervical cancer prevention and control.

The United States-Mexico border is a region comprised of a country with one of the highest rates of invasive cervical cancer (Mexico) and a country with one of the lowest rates (United States). Recent evidence clearly indicates that human papillomavirus (HPV) infection is the cause of cervical cancer. The distribution of specific types of HPV is known to vary in different regions of the world, as do the cofactors that may inhibit or promote HPV carcinogenesis. Estimating the prevalence of oncogenic HPV is needed for guiding vaccine development. The purpose of this study was to determine the prevalence of oncogenic and nononcogenic HPV types and risk factors for HPV among women residing along the United States-Mexico border. A cross-sectional study of 2319 women, ages 15-79 years, self-referring for gynecological care was conducted between 1997 and 1998. HPV was detected by PCR using the PYGMY 09/11 L1 consensus primer, and HPV genotyping was conducted using the reverse line blot method. Overall, the HPV prevalence was 14.4% with no significant differences observed by country after adjustment for age. HPV 16 was the most commonly detected HPV type in both the United States and Mexico. Among women with high-grade squamous intraepithelial lesions, HPV types 58, 45, 51, 31, 35, 55, and 73 were most common in Mexico, and HPV types 18, 31, 35, 51, 52, and 58 were most common in the United States. In both countries, HPV prevalence declined linearly with age from 25% among women ages 15-19 years to 5.3% among women 56-65 years. Factors significantly independently associated with HPV infection were older age [adjusted odds ratio (AOR) = 0.15 for ages 56-65 years compared with those 15-19 years], a marital status other than married (AOR = 1.58-3.29), increased numbers of lifetime male partners (AOR = 3.8 for > or =10 partners compared with 1 partner), concurrent infection with Chlamydia trachomatis (AOR = 1.79), ever use of Norplant (AOR = 2.69), and current use of injectable contraceptives (AOR = 2.29). Risk factors for HPV infection did not differ by country. Results from this study suggest that in addition to HPV 16 and 18, HPV types 31, 45, 51, and 58 should be considered for inclusion in an HPV prevention vaccine for distribution in Mexico.

Adolescent↗
PubMed2000

[Efficacy of group therapy of alcoholics. Results of a controlled clinical trial].

BACKGROUND: Group therapy is widely used in psychiatry and psychology, specially in the treatment of alcoholism. Nevertheless, scientific evidence of its efficacy is scarce, and professionals tend very often to doubt about its usefulness. METHODS: Clinical trial to test the efficacy of group therapy to improve abstinence and compliance of alcoholics (CIE-10 criteria) randomly assigned to standard treatment plus group therapy (TG+, n = 45) versus standard treatment alone (TG-, n = 43) during 12 months. RESULTS: At 6 months follow up, the percentage of alcohol consumers (26 vs 20%) and dropouts (49 vs 36%), was slightly higher among the TG- group; while Cumulated Abstinence Duration (131 days [SD 57] versus 135 days [SD 64]) tended to be higher in the TG+ group. Differences increase at the one year follow up, reaching a significant level when measuring time to first relapse (233 vs 382 days; p = 0.04). Also, the probability to remain abstinent is clearly lower in the TG- (31 vs 76%). CONCLUSIONS: These results clearly show the efficacy of group therapy. Its effect appears from the 3rd month and increases from 6th to 12th months. Some patients, specially those who will have worse clinical evolution, refuse to attend group sessions. Also, some others who don't accept an abstinence oriented treatment, may interfere in group dynamics. In order to maximize group efficacy, extreme care should be taken in selection of patients, group composition, setting and leadership style.

Adult↗
PubMed2000

A comparative study of the ability of different solvents and adsorbents to extract aroma compounds from alcoholic beverages.

Seven liquid solvent systems--dichloromethane, dichloromethane-pentane (1:1), freon 113, diethyl ether-pentane (1:1 and 1:9), ethyl acetate-pentane (with and without an additional salting-out effect) (1:3 and 1:20), and seven solid-phase extraction (SPE) systems (Amberlite XAD-2, 4, 7, and 16; Porapak Q; C8; and C18)--are comparatively studied. The distribution coefficients between the extraction system and a hydroalcoholic solution (12% v/v in ethanol, pH = 3.2) of 14 selected volatile compounds belonging to different chemical families and polarities are calculated. The results are processed by factor analysis and cluster analysis, and the following conclusions are reached. First, the efficiency of extraction decreases in this order: polymeric sorbents > silica-based sorbents > liquid-liquid systems with salting-out effect approximately dichloromethane > rest of liquid solvents. Second, the addition of salt mainly increases the recovery of compounds with Lewis acid properties. Third, the efficiency of the extraction of a liquid solvent depends not only on its polarity but also on its solubility in water. Fourth, in regards to the selectivity of the SPE systems, Porapak Q is the best to extract nonpolar compounds, Amberlite XAD 4 and 16 provide the least selective extraction profiles, and C8 and C18 have a special ability to extract compounds with a Brønstedt-Lowry character. Results indicate that in all cases liquid solvents can be replaced satisfactorily by SPE systems.

Adsorption↗
PubMed2000

Mercury toxicity due to use of a cosmetic cream.

The Arizona Department of Health Services performed an investigation to determine the health effects associated with the use of a mercury-containing beauty cream. A urine test for mercury was offered to cream users who contacted the Arizona Department of Health Services. Those with urine mercury levels > 20 micrograms/L were offered clinical evaluation. Eighty-nine urine specimens were submitted for testing. Of these, 66 showed an elevated urine mercury level (> 20 micrograms/L), and 55 people were evaluated in clinic. There were no major abnormalities found through physical examination or laboratory testing. Urine mercury levels declined from an initial mean of 170 micrograms/L to 32 micrograms/L at the final test (mean, 139 days later). The high urine mercury levels indicate that the use of this cosmetic cream constitutes a significant exposure. Neuropsychiatric symptoms were frequently reported, but few objective signs were noted.

Adolescent↗
PubMed1999

Post-Paget telangiectatic osteosarcoma of the skull.

Sarcomatous transformation is the most dreaded complication of Paget's disease. We report on a case of post-Paget telangiectatic osteosarcoma of the skull, a variant of osteogenic osteosarcoma, in a 79-year-old woman. We discuss the radiological pattern in relationship to the differential diagnosis.

Aged↗
PubMed1998

Trace element analysis on Si wafer surfaces by TXRF at the ID32 ESRF undulator beamline.

Synchrotron radiation total-reflection X-ray fluorescence (SR-TXRF) has been applied to the impurity analysis of Si wafers using a third-generation synchrotron radiation undulator source. A lower limit of detectability (LLD) for Ni atoms of 17 fg (1.7 x 10(8) atoms cm(-2)) has been achieved with an optical set-up based on an Si(111) double-crystal monochromator and a horizontal sample geometry. These first results are very promising for synchrotron radiation trace element analysis since we estimate that it is possible to lower the LLD by a factor of about 25 by employing appropriate optics and detectors. The use of a crystal monochromator opens new possibilities to perform absorption and scattering experiments (NEXAFS and X-ray standing-wave methods) for chemical and structural analysis of ultratrace elements.

Journal Article↗
PubMed1998

ACE inhibitor quinapril reduces the arterial expression of NF-kappaB-dependent proinflammatory factors but not of collagen I in a rabbit model of atherosclerosis.

Increasing evidence supports an association between inflammation and plaque rupture. Macrophages and vascular smooth muscle cells are a source of cytokines and growth factors, which contribute to ongoing inflammation during atherogenesis. In a rabbit model of atherosclerosis, we evaluated the effect of the ACE inhibitor quinapril on different parameters implicated in the pathogenesis of the plaque, such as the presence of chemokines (interleukin-8, monocyte chemoattractant protein-1), collagen I, and vascular smooth muscle cell proliferation (PDGF-B). Since nuclear factor kappaB (NF-kappaB) has been implicated in the control of chemokine transcription and cell proliferation, we also investigated its activation and localization in the lesion. Quinapril administration for 28 days caused a down-regulation in arterial expression of interleukin-8 and monocyte chemoattractant protein-1 (mRNA and protein). However, collagen I expression (mRNA and protein) was not modified. PDGF-B expression was reduced in both the intima and the media. Active NF-kappaB, found in both macrophages and vascular smooth muscle cells, was also reduced by quinapril. Nevertheless, no significant changes were noted in the mild neointima formation, although a certain trend toward normalization was found in the quinapril-treated group. In conclusion, our results show that quinapril treatment attenuates several parameters associated with inflammation within the atherosclerotic lesions that are controlled by NF-kappaB, although it has no effect on collagen I expression. Both effects could contribute to the stabilization of the atherosclerotic plaque.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed1998

HMG-CoA reductase inhibition by atorvastatin reduces neointimal inflammation in a rabbit model of atherosclerosis.

OBJECTIVES: To study the effect of the 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA)-reductase inhibitor atorvastatin on the potential mechanisms involved in the recruitment of monocytic cells into the vessel wall. BACKGROUND: Inhibitors of HMG-CoA-reductase reduce cardiovascular mortality though the mechanisms yet elucidated. Most ischemic events are secondary to disruption of atherosclerotic plaques highly infiltrated by macrophages. METHODS: Atherosclerosis was induced in the femoral arteries of rabbits by endothelial damage and atherogenic diet for 4 weeks. Then, animals were switched to standard chow and randomized to receive either no treatment or atorvastatin (5 mg/kg/d) and killed after 4 weeks. RESULTS: Atorvastatin induced a significant reduction in serum lipids and in lesion size. Arterial macrophage infiltration was abolished by the treatment, and monocyte chemoattractant protein-1 (MCP-1) was significantly diminished in the neointima and in the media. Nuclear factor kappa-B (NF-kappaB) was activated in the 60% of the lesions, both in macrophages and vascular smooth muscle cells (VSMC), of the untreated group while only in 30% of the atorvastatin group. NF-kappaB activity was also lower in the uninjured aorta and liver of treated compared with untreated rabbits. In cultured VSMC, MCP-1 expression and NF-kappaB activity induced by tumor necrosis factor alpha were downregulated by atorvastatin. CONCLUSIONS: In a rabbit atherosclerosis model, atorvastatin diminishes the neointimal inflammation, and this could contribute to the stabilization of the atherosclerotic plaque. This may be an additional explanation for the reduction of acute ischemic events in patients treated with statins.

Animals↗
PubMed1998

[The topographic diagnosis of the sympathetic nervous system lesions in Cuban epidemic neuropathy. The value of the sympathetic skin response].

The purpose of this study is to demonstrate from the electrophysiological point of view the existence of disorders of the autonomic nervous system (ANS) and to deepen in the probable topography of the lesions. The sympathetic skin response (SSR) was studied in 37 patients with Cuban epidemic neuropathy (CEN) and in 29 sound individuals. The response to electrical stimulation with simultaneous registry in the 4 limbs was assessed. The latencies and amplitudes of the SSR registered in the lower limbs of patients were significantly different from those of the controls (p < 0.05). This difference between both groups was not observed in the upper limbs. These results are an objective and reproducible evidence of the injury of the ANS in the Cuban epidemic neuropathy. The highest intensity of affectation of the amplitudes of the SSR of lower limbs, with relative indemnity of those of the upper limbs, suggests a predominance of the axonal injury of the peripheral efferent branch towards the lower limbs that is congruent with the greatest affectation of the peripheral nerves in this localization.

Adult↗
PubMed1997

Fine-needle aspiration cytology of mammary fibromatosis: report of two cases.

The purpose of this study is to evaluate cytologically two cases of mammary fibromatosis (MF). Prior to FNAC, clinical and mammographic suspicion of carcinoma and fibroadenoma were present. In both cases cytology disclosed the presence of numerous spindle cells admixed with epithelial cells. In the first case, carcinoma was excluded and the diagnosis of "spindle-cell proliferative lesion" was established. The second case was erroneously diagnosed as "cellular fibroadenoma" due to the presence of monolayered ductal epithelial groups and stromal tissue. In both cases local excision of the lesion was recommended. Although in a strict sense fibromatosis is a pure stromal lesion, the frequent presence of epithelial groups in the smears should raise a differential diagnosis with other more frequent mixed (epithelial and stromal) lesions such as fibroadenoma, cystosarcoma phyllodes, and metaplastic carcinoma. Due to the fact that clinically and mamographically MF is frequently confused with malignancy, preoperative recognition is essential since in many cases it would avoid unnecessary radical surgery. In this sense cytology offers very important preoperative information.

Adult↗
PubMed1997

Resistance to apoptosis and up regulation of Bcl-2 in benign prostatic hyperplasia after androgen deprivation.

PURPOSE: Benign prostatic hyperplasia (BPH) is related to advancing age and the presence of androgens and occurs in virtually all older men. BPH causes morbidity, most often by urinary obstruction, in a substantial fraction of men over sixty. Both finasteride and androgen ablation induce partial diminution in BPH that occurs over weeks to months. This is in contrast to the often rapid involution seen in both normal prostatic epithelium and prostatic carcinoma in response to androgen withdrawal. This study was performed to analyze the response of prostatic cells, and in particular BPH, to acute androgen ablation. MATERIALS AND METHODS: We subjected a cohort of 26 men to androgen ablation with goserelin, a gonadotrophin releasing hormone agonist, for 3-4 weeks prior to radical prostatectomy for prostate cancer. Preablation biopsy specimens and prostatectomy specimens were immunohistochemically stained for apoptotic cells and for expression of apoptosis regulatory proteins Bcl-2, Bax, Bcl-x, and Bak. RESULTS: Normal prostatic epithelial cells and prostate cancer responded to hormone deprivation by undergoing apoptosis, but in 19/26 specimens prostatic hyperplasia had a total absence of apoptosis. In all 26 specimens, benign prostatic hyperplasia demonstrated increased expression of the Bcl-2 protein, but no change in the expression of Bax, Bcl-x, and Bak. In contrast, adjacent normal and malignant prostatic epithelium showed positive staining for apoptosis and did not alter Bcl-2 expression in response to androgen ablation. CONCLUSIONS: BPH demonstrated increased staining for Bcl-2 after androgen deprivation that may render hyperplastic epithelium relatively resistant to apoptosis induced acutely by androgen withdrawal.

Apoptosis↗
PubMed1997

[Prognostic value of lymphatic metastasis in bladder cancer].

OBJECTIVE: The presence of lymph node metastasis in bladder cancer is considered to be a sign of poor prognosis. The present study was performed to analyze the influence of the number of positive lymph nodes on survival and the therapeutic value of lymphadenectomy in pN+patients. METHODS: From January, 1983 to January, 1993, 160 patients aged 39 to 77 years (mean 61.8) underwent radical cystectomy and pelvic lymphadenectomy for carcinoma of the bladder. The records of 122 patients were available for review. The UICC 1978 classification system was used. RESULTS: Cancer-specific mortality was 22.8% (16/70) for pNo patients, 44.4% (4/9) for pN1 patients and 88.9% (16/18) for pN2-4 patients. We obtained the following cancer-specific mortality by stratifying according to T category: 5.4% (2/37) for pNoT1-T3a, 42.4% (14/33) for pNoT3b-T4, 0% (0/2) for pNIT1-T3a, 57.1% (4/7) for pNIT3b-T4 and 88.9% (16/18) for pN2-4T3b-T4. CONCLUSION: The presence of only 1 positive regional lymph node (pN1) appears to worsen patient survival, particularly when the primary tumor is T3b or worse. In these cases cancer-specific mortality after patient discharge increased from 42% for the pNo patients to 57% for the pN1 patients (p > 0.05). Radical cystectomy was highly effective and curative in 95% of T1-T3apNo-1 patients (37/39). The presence of multiple positive lymph nodes carries a very poor prognosis, with 89% of the patients dying at a mean of 12 months.

Adult↗
PubMed1996

[Isolated laryngeal candidiasis. Description of 2 cases and review of the literature].

Infection of the larynx by Candida is rare and usually accompanies lung or disseminated candidiasis. The incidence of isolated laryngeal candidiasis (ILC) is low, although it may be underestimated. We describe 2 patients with ILC confirmed during autopsy: a 45-years-old male with pulmonary fibrosis and a 4-years-old girl with acute myeloblastic leukemia. Hoarseness and dysphagia are the most common symptoms of ILC. The most effective diagnostic technique is laryngoscopy with specimen culture and/or histopathology. Specimens usually show whitish plaques on the larynx. Most ILC patients have some associated disease and/or predisposing factors, with frequent antibiotic treatment prior to the advent of candidiasis. Intravenous amphotericin B provides the most effective therapy, although other antimycotics are also useful. Early diagnosis and initiation of therapy curtail the disease and can prevent systemic dissemination.

Adolescent↗