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1.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21260003

RESUMO

BackgroundThe COVID-19 pandemic created the need for very large scale, rapid testing to prevent and contain transmission of the SARS-CoV-2 virus. Lateral flow device (LFD) immunoassays meet this need by indicating the presence of SARS-CoV-2 antigen from nose/throat swab washings in 30 minutes without laboratory processing, and can be manufactured quickly at low cost. Since March 2021, UK schools have asked pupils without symptoms to test twice weekly. Pupils have posted on social media about using soft drinks to create positive results. The aim of this study was to systematically test a variety soft drinks to determine whether they can cause false "false positive" LFD results. MethodsThis study used 14 soft drinks and 4 artificial sweeteners to determine the outcome of misusing them as analyte for the Innova SARS-CoV-2 antigen rapid qualitative LFD. The pH value, sugar content and ingredients of each sample are described. The LFD results were double read and a subset was repeated using the same devices and fake analytes but differently sourced. FindingsOne sample (1/14; 7%), spring water, produced a negative result. Ten drinks (10/14; 71%) produced a positive or weakly positive result. Three samples (3/14; 21%) produced void results, mostly the fruit concentrate drinks. There was no apparent correlation between the pH value (pH 5.0 in 13/14, 93%; pH 6.5 in 1/14; 7%) or the sugar content (range 0-10.7 grams per 100mls) of the drinks and their LFD result. The 4 artificial sweeteners all produced negative results. A subset of the results was fully replicated with differently sourced materials. InterpretationSeveral soft drinks can be misused to give false positive SARS-CoV-2 LFD results. Daily LFD testing should be performed first thing in the morning, prior to the consumption of any food or drinks, and supervised where feasible. FundingThis work was self-funded by author LO and the LFD were gifted for use in this study. Research in contextO_ST_ABSEvidence before this studyC_ST_ABSO_LILateral flow devices (LFD) for SARS-CoV-2 antigen testing have been used extensively in the UK and internationally in COVID-19 pandemic responses, providing rapid testing at low cost C_LIO_LIRecent reports from young people on social media suggested soft drinks might be misused as LFD analyte and produce a seemingly positive result C_LI Added value of this studyO_LIVarious common soft drinks used as fake analyte can produce false positive SARS-CoV-2 LFD results C_LIO_LIArtificial sweeteners alone in fake analyte solution did not produce false positive results C_LI Implications of all the available evidenceO_LISoft drinks misused as analyte can produce false "false positive" SARS-CoV-2 LFD results C_LIO_LIDaily testing is best done first thing in the morning, prior to any food or drink, and under supervision where possible C_LI

2.
Br J Cancer ; 124(6): 1169-1174, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33414539

RESUMO

BACKGROUND: Epidemiological studies of the relationship between gallstone disease and circulating levels of bilirubin with risk of developing colorectal cancer (CRC) have been inconsistent. To address possible confounding and reverse causation, we examine the relationship between these potential risk factors and CRC using Mendelian randomisation (MR). METHODS: We used two-sample MR to examine the relationship between genetic liability to gallstone disease and circulating levels of bilirubin with CRC in 26,397 patients and 41,481 controls. We calculated the odds ratio per genetically predicted SD unit increase in log bilirubin levels (ORSD) for CRC and tested for a non-zero causal effect of gallstones on CRC. Sensitivity analysis was applied to identify violations of estimator assumptions. RESULTS: No association between either gallstone disease (P value = 0.60) or circulating levels of bilirubin (ORSD = 1.00, 95% confidence interval (CI) = 0.96-1.03, P value = 0.90) with CRC was shown. CONCLUSIONS: Despite the large scale of this study, we found no evidence for a causal relationship between either circulating levels of bilirubin or gallstone disease with risk of developing CRC. While the magnitude of effect suggested by some observational studies can confidently be excluded, we cannot exclude the possibility of smaller effect sizes and non-linear relationships.


Assuntos
Colelitíase/epidemiologia , Neoplasias Colorretais/epidemiologia , Predisposição Genética para Doença , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Colelitíase/complicações , Colelitíase/genética , Neoplasias Colorretais/complicações , Neoplasias Colorretais/genética , Estudo de Associação Genômica Ampla , Humanos , Prognóstico , Fatores de Risco , Reino Unido/epidemiologia
3.
J Am Mosq Control Assoc ; 36(2s): 90-97, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33647138

RESUMO

Vector Disease Control International (VDCI) has a long history of aiding mosquito control efforts necessary for recovery after natural disasters like hurricanes and major floods. As waters associated with these events begin to recede, both nuisance and vector mosquito species surge in abundance and consequently play an increased role in public health. When these situations arise, state and county agencies implement emergency response plans and many rely on Federal Emergency Management Agency or private contractors for assistance in reducing mosquito populations that can alter arbovirus transmission cycles, cause intolerable stress, hamper reconstruction efforts, and disrupt normal community functions. Vector Disease Control International owns the largest fleet of fixed-wing aircraft dedicated specifically to mosquito control and has worked every major storm event since Hurricane Bonnie in 1998. This article describes the logistics and operations required for implementing VDCI's emergency management plan, including the relocation of equipment, adult mosquito surveillance, delivery of pesticides, assessment of efficacy, and filing of low-level waivers and congested-area plans with the Federal Aviation Administration.


Assuntos
Defesa Civil/organização & administração , Tempestades Ciclônicas , Controle de Mosquitos/organização & administração , Parcerias Público-Privadas , Aeronaves/estatística & dados numéricos , Estados Unidos
4.
Clin Infect Dis ; 69(Suppl 7): S529-S537, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31724044

RESUMO

Iron is an essential nutrient for bacterial growth, replication, and metabolism. Humans store iron bound to various proteins such as hemoglobin, haptoglobin, transferrin, ferritin, and lactoferrin, limiting the availability of free iron for pathogenic bacteria. However, bacteria have developed various mechanisms to sequester or scavenge iron from the host environment. Iron can be taken up by means of active transport systems that consist of bacterial small molecule siderophores, outer membrane siderophore receptors, the TonB-ExbBD energy-transducing proteins coupling the outer and the inner membranes, and inner membrane transporters. Some bacteria also express outer membrane receptors for iron-binding proteins of the host and extract iron directly from these for uptake. Ultimately, iron is acquired and transported into the bacterial cytoplasm. The siderophores are small molecules produced and released by nearly all bacterial species and are classified according to the chemical nature of their iron-chelating group (ie, catechol, hydroxamate, α-hydroxyl-carboxylate, or mixed types). Siderophore-conjugated antibiotics that exploit such iron-transport systems are under development for the treatment of infections caused by gram-negative bacteria. Despite demonstrating high in vitro potency against pathogenic multidrug-resistant bacteria, further development of several candidates had stopped due to apparent adaptive resistance during exposure, lack of consistent in vivo efficacy, or emergence of side effects in the host. However, cefiderocol, with an optimized structure, has advanced and has been investigated in phase 1 to 3 clinical trials. This article discusses the mechanisms implicated in iron uptake and the challenges associated with the design and utilization of siderophore-mimicking antibiotics.


Assuntos
Infecções Bacterianas/tratamento farmacológico , Cefalosporinas/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Ferro/metabolismo , Sideróforos/farmacologia , Cefalosporinas/química , Desenho de Fármacos , Desenvolvimento de Medicamentos , Farmacorresistência Bacteriana , Humanos , Modelos Moleculares , Sideróforos/química , beta-Lactamas/farmacologia , Cefiderocol
5.
Fertil Steril ; 90(5): 2016.e7-10, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18394621

RESUMO

OBJECTIVE: To report a pregnancy in a hermaphrodite and review of the literature. DESIGN: Case report and literature review. SETTING: Clinical. PATIENT(S): A patient with male-predominant mosaic karyotype 96% 46XY. INTERVENTION(S): Removal of left ovotestis in combination with a supracervical hysterectomy and bilateral salpingo-oophorectomy. MAIN OUTCOME MEASURE(S): Identification of published cases of pregnancy and hermaphroditism. RESULT(S): The current patient had previous pregnancy and a wedge biopsy of her left gonad, which demonstrated an ovotestis and an area suspicious for a gonadoblastoma. After delivery of her second pregnancy, the patient underwent a hysterectomy and bilateral salpingo-oophorectomy. The histopathologic evaluation following bilateral oophorectomy demonstrated a residual ovotestis without further evidence of a gonadoblastoma. Review of the literature identified 10 other cases of pregnancy in a hermaphrodite patient. CONCLUSION(S): This is the 11th reported case of fertility in a true hermaphrodite and only the second report of a mosaic true hermaphrodite to demonstrate fertility. This is the only case of a pregnancy involving a male-predominant mosaic 96% 46XY and the only case to confirm the genetics of the offspring.


Assuntos
Fertilidade , Disgenesia Gonadal Mista/fisiopatologia , Ovário/patologia , Transtornos Ovotesticulares do Desenvolvimento Sexual/fisiopatologia , Testículo/patologia , Adulto , Feminino , Disgenesia Gonadal Mista/genética , Disgenesia Gonadal Mista/patologia , Gonadoblastoma/genética , Gonadoblastoma/patologia , Gonadoblastoma/prevenção & controle , Humanos , Histerectomia , Cariotipagem , Laparoscopia , Nascido Vivo , Masculino , Mosaicismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/prevenção & controle , Ovariectomia , Ovário/cirurgia , Transtornos Ovotesticulares do Desenvolvimento Sexual/genética , Transtornos Ovotesticulares do Desenvolvimento Sexual/patologia , Gravidez , Neoplasias Testiculares/genética , Neoplasias Testiculares/patologia , Neoplasias Testiculares/prevenção & controle , Testículo/cirurgia
6.
Eur J Oncol Nurs ; 11(3): 212-23; discussion 224-7, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17188938

RESUMO

One of the main challenges of colorectal cancer follow-up is the detection of early disease in order to influence survival and improve outcome. Yet, the benefits of follow-up are not only related to survival. It is well documented that patients can experience an array of problems following colorectal cancer surgery which impact upon quality of life, therefore symptom management plays an important part in the overall spectrum of follow-up care. In addition, there is emerging evidence to suggest that clinical nurse specialists are well placed in the multidisciplinary team to co-ordinate such follow-up programmes. This paper reports on a pilot study designed to assess the feasibility of a follow-up programme led by nurse specialists for patients with colorectal cancer. Key outcome areas were adherence to an agreed follow-protocol, quality of life, patient and clinician satisfaction and a cost-analysis of the new model. The study was conducted over one year with 60 patients. This redesign resulted in a smoother pathway of follow-up care, improved quality of life and acceptance to both patients and clinicians alike. The introduction of a nurse-led follow-up model is expected to demonstrate cost savings over a 3 year rolling follow-up programme.


Assuntos
Assistência ao Convalescente/organização & administração , Neoplasias Colorretais/prevenção & controle , Liderança , Enfermeiros Clínicos/organização & administração , Enfermagem Oncológica/organização & administração , Equipe de Assistência ao Paciente/organização & administração , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/psicologia , Redução de Custos , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Enfermagem , Papel do Profissional de Enfermagem , Pesquisa em Avaliação de Enfermagem , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Projetos Piloto , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Qualidade de Vida/psicologia , Escócia
8.
Life Sci ; 69(22): 2675-83, 2001 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-11712670

RESUMO

Elevated levels of serum free fatty acids (FFA) may be the metabolic alteration in obesity that leads to insulin resistance (IR) and type 2 diabetes mellitus (DM). The obese Zucker rat (ZR) is a genetic model of juvenile-onset obesity and type 2 DM. Compared with its lean sibling, the obese ZR is hyperinsulinemic, hypertriglyceridemic, and, beginning at about 6 months, hyperglycemic. The obese ZR demonstrates also IR, hyperphagia, increased lipogenesis, adipocyte hypertrophy and hyperplasia, and increased serum FFA levels. This study was designed to determine if serum FFA levels in lean and obese ZRs correlate with metabolic parameters associated with altered energy metabolism and IR. We hypothesized that serum FFA levels correlate with such serum parameters such as insulin, glucose, triglyceride, and total cholesterol, as well as such tissue parameters as retroperitoneal, perirenal, and epididymal fat pad weights and liver total lipid content. Twenty lean and 20 obese ZR were age/weight matched. For 14 days each rat had ad libitum access to a single bowl diet that was 50% fat, 30% carbohydrate, and 20% protein. Body weights and caloric intakes were measured daily. After 14 days, all animals were fasted overnight and euthanized. Serum and tissue measurements were made and various parameters were correlated with FFA levels. Serum FFA levels were almost 2 times higher in the obese ZR (approximately 1 mmol/L) compared to the lean (approximately 0.6 mmol/L). Each variable measured was significantly (p < or = 0.05) greater in the obese ZR compared to the lean. There were significant correlations between serum FFA levels and certain variables when data from all ZR were plotted against serum and tissue parameters. However, within phenotypes, there were no significant correlations. Serum FFA levels predict serum and tissue parameters that accompany obesity and IR when comparing lean and obese rats. However, FFA do not predict such parameters within one phenotype.


Assuntos
Ácidos Graxos não Esterificados/metabolismo , Resistência à Insulina/fisiologia , Obesidade/metabolismo , Animais , Dieta , Modelos Animais de Doenças , Masculino , Ratos , Ratos Zucker
9.
Exp Biol Med (Maywood) ; 226(8): 782-9, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11520945

RESUMO

High levels of serum free fatty acids (FFA) and lower proportions of polyunsaturated (PU) FAs, specifically arachidonic acid (AA), are common in obesity, insulin resistance (IR), and type 2 diabetes mellitus. Dehydrepiandrosterone (DHEA) decreases body fat content, dietary fat consumption, and insulin levels in obese Zucker rats (ZR), a genetic model of human youth onset obesity and type 2 diabetes. This study was conducted to investigate DHEA's effects on lean and obese ZR serum FFA levels and total lipid (TL) FA profiles in heart and soleus muscle. We postulated that DHEA alters serum FFA levels and tissue TL FA profiles of obese ZR so that they resemble the levels and profiles of lean ZR. If so, DHEA may directly or indirectly alter tissue lipids, FFA flux, and perhaps lower IR in obese ZR. Lean and obese male ZR were divided into six groups with 10 animals in each: obese ad libitum control, obese pair-fed, obese DHEA, lean ad libitum control, lean pair-fed, and lean DHEA. All animals had ad libitum access to a diet whose calories were 50% fat, 30% carbohydrate, and 20% protein. Only the diets of the DHEA treatment groups were supplemented with 0.6% DHEA. Pair-fed groups were given the average number of calories per day consumed by their corresponding DHEA group, and ad libitum groups had 24-h access to the DHEA-free diet. Serum FFA levels and heart and soleus TL FA profiles were measured. Serum FFA levels were higher in obese (approximately 1 mmol/L) compared to lean (approximately 0.6 mmol/L) ZR, regardless of group. In hearts, monounsaturated (MU) FA were greater and PU FA were proportionally lower in obese compared to the lean rats. In soleus, saturated and MU FA were greater and PU FA were proportionally lower in the obese compared to the lean rats. DHEA groups displayed significantly increased proportions of TL AA and decreased oleic acid in both muscle types. Mechanisms by which DHEA alters TL FA profiles are a reflection of changes occurring within specific lipid fractions such as FFA, phospholipid, and triglyceride. This study provides initial insights into DHEA's lipid altering effects.


Assuntos
Adjuvantes Imunológicos/farmacologia , Desidroepiandrosterona/farmacologia , Metabolismo dos Lipídeos , Músculo Esquelético/efeitos dos fármacos , Miocárdio/metabolismo , Animais , Peso Corporal , Ácidos Graxos Monoinsaturados/sangue , Ácidos Graxos não Esterificados/sangue , Ácidos Graxos Insaturados/sangue , Coração/efeitos dos fármacos , Masculino , Obesidade/sangue , Ratos , Ratos Zucker , Fatores de Tempo
10.
Atherosclerosis ; 158(1): 215-25, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11500194

RESUMO

The immunohistochemical distribution of apolipoproteins in the abdominal aortas of 142 men, 15-34 years of age, collected in a cooperative multicenter study group (Pathobiological Determinants of Atherosclerosis in Youth) was examined in relationship to serum VLDL+LDL+HDL cholesterol levels. ApoB deposits were limited to the intima of specimens with intimal fibro cellular thickening or atherosclerotic lesions. Apo A-I, E and J were observed in both the intima and media of the aortas with intimal lesions. The pattern of apoJ distribution was similar to that of apoA-I and E. The distribution patterns of these apolipoproteins in these young adults were very similar to those in adults and old men seen in an earlier study. The extent of apolipoprotein distribution in the intima and media increased with age and the stage of atherosclerosis development, but was not correlated significantly with serum VLDL+LDL or HDL cholesterol levels. The infiltration of lipoprotein particles into the aortic wall seems to be more strongly associated with the progression of intimal lesions rather than with serum cholesterol levels.


Assuntos
Aorta Abdominal/química , Doenças da Aorta/metabolismo , Apolipoproteínas/análise , Arteriosclerose/metabolismo , Adolescente , Adulto , Doenças da Aorta/sangue , Doenças da Aorta/patologia , Apolipoproteína A-I/análise , Apolipoproteínas E/análise , Arteriosclerose/sangue , Arteriosclerose/patologia , Colesterol/sangue , Clusterina , Feminino , Glicoproteínas/análise , Humanos , Imuno-Histoquímica , Masculino , Chaperonas Moleculares/análise , Fatores de Risco , Túnica Íntima/química , Túnica Média/química
11.
Atherosclerosis ; 156(2): 389-99, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11395036

RESUMO

To investigate whether histopathological modifications on early atherosclerotic lesions differ according to risk factors, we compared the histological findings of arteries obtained from a multicenter study in the USA (Pathobiological Determinants of Atherosclerosis in Youth, PDAY) with the antemortem risk factors. The materials comprised aortas and left anterior descending (LAD) coronary arteries of 140 male subjects. Measurements of intimal thickness, classification of intimal lesions, and density of foam cells and intimal fibrosis at the determined sites of LAD and aorta were evaluated. In both arteries, intimal thickness of hypertensives was greater than the normotensives with no definite proliferation of foam cells. In aortas, hypercholesterolemia was associated with an increase in foam cells, but not with an increase in intimal thickness. HDL-C value correlated inversely with number of foam cells in both the arteries, and the degree of intimal thickness in LADs, where early appearance of advanced lesion such as preatheroma and atheroma, was also indicated in the low HDL-C group. Smokers had less number of foam cells in both the arteries and more intensive intimal fibrosis in LAD than non-smokers. Our study suggests that there are several ways to advanced atherosclerotic lesions by risk factors.


Assuntos
Aorta Torácica/patologia , Arteriosclerose/patologia , Vasos Coronários/patologia , Túnica Íntima/patologia , Adolescente , Adulto , Análise de Variância , Arteriosclerose/sangue , Arteriosclerose/epidemiologia , Autopsia , HDL-Colesterol/sangue , Comorbidade , Técnicas de Cultura , Fibrose , Hemoglobinas Glicadas/análise , Humanos , Japão/epidemiologia , Modelos Logísticos , Masculino , Probabilidade , Fatores de Risco , Índice de Gravidade de Doença , Fumar/epidemiologia
12.
Circulation ; 103(11): 1546-50, 2001 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-11257083

RESUMO

BACKGROUND: The strong association between coronary heart disease and dyslipoproteinemia has often overshadowed the effects of the nonlipid risk factors-smoking, hypertension, obesity, and diabetes and impaired glucose tolerance-and even led to questioning the importance of these risk factors in the presence of a favorable lipoprotein profile. METHODS AND RESULTS: A cooperative multicenter study, the Pathobiological Determinants of Atherosclerosis in Youth (PDAY), examined the relation of the nonlipid risk factors to atherosclerosis in 629 men and 227 women 15 to 34 years of age who died of external causes and who had a favorable lipoprotein profile (non-HDL cholesterol <4.14 mmol/L [<160 mg/dL] and HDL cholesterol >/=0.91 mmol/L [>/=35 mg/dL]). In the abdominal aorta, smokers had more extensive fatty streaks and raised lesions than nonsmokers, and hypertensive blacks had more raised lesions than normotensive blacks. In the right coronary artery, hypertensive blacks had more raised lesions than normotensive blacks, obese men (body mass index >/=30 kg/m(2)) had more extensive fatty streaks and raised lesions than nonobese men, and individuals with impaired glucose intolerance had more extensive fatty streaks. Obese men had more severe lesions (American Heart Association grade 2 through 5) of the left anterior descending coronary artery. CONCLUSIONS: These substantial effects of the nonlipid risk factors on the extent and severity of coronary and aortic atherosclerosis, even in the presence of a favorable lipoprotein profile, support the need to control all cardiovascular risk factors.


Assuntos
Arteriosclerose/epidemiologia , Complicações do Diabetes , Intolerância à Glucose/complicações , Hipertensão/complicações , Lipoproteínas/metabolismo , Obesidade/complicações , Fumar/efeitos adversos , Adolescente , Adulto , Arteriosclerose/etiologia , Feminino , Humanos , Masculino , Fatores de Risco , Fatores Sexuais
13.
Am Heart J ; 141(2 Suppl): S58-62, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11174360

RESUMO

BACKGROUND: Coronary artery disease in women appears 10 to 15 years later than in men. To test the hypothesis that the effects of estrogen may manifest themselves as histologic differences in coronary plaques, we examined the hearts of premenopausal and postmenopausal women who died suddenly from coronary artery disease. METHODS: We studied 51 cases of sudden coronary death and 47 deaths in women who died from noncoronary causes. Coronary deaths were classified on the basis of histologic features. The number of acute plaque ruptures, healed plaque ruptures, vulnerable plaques, and acute plaque erosions were compared between groups. Postmortem values of serum total cholesterol, HDL cholesterol, and thiocyanate were measured, and menopausal status was confirmed by calculating body mass index. RESULTS: Women older than 50 years of age were much more likely to have a ruptured plaque than were younger, premenopausal women. Plaque rupture was significantly associated with elevated total cholesterol level. In the 51 women who died of coronary disease, the mean number of vulnerable plaques increased significantly as women advanced into the postmenopausal years. CONCLUSIONS: Our data suggest that estrogen has an anti-inflammatory effect on atherosclerotic plaques, resulting in plaque stabilization. Plaque erosion, the major substrate for thrombosis in premenopausal women, does not appear to be inhibited by estrogen. Because plaque progression may result both from repeated rupture and repeated erosion, a better understanding of the effect of estrogen on atherosclerosis may yield insights into the nature of coronary artery disease.


Assuntos
Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Menopausa , Cadáver , Colesterol/sangue , Doença da Artéria Coronariana/sangue , Doença da Artéria Coronariana/mortalidade , Morte Súbita Cardíaca/patologia , Progressão da Doença , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Ruptura Espontânea
14.
Circulation ; 103(7): 934-40, 2001 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-11181466

RESUMO

BACKGROUND: Subclinical episodes of plaque disruption followed by healing are considered a mechanism of increased plaque burden. Detailed pathological studies of healed ruptures, however, are lacking. METHODS AND RESULTS: We identified acute and healed ruptures from 142 men who died of sudden coronary death and performed morphometric measurements of plaque burden, luminal stenosis, and smooth muscle cell phenotype. Healed ruptures were found in 61% of hearts and were associated with healed myocardial infarction, increased heart weight, dyslipidemia, and diabetes. Multiple healed rupture sites with layering were frequently found in segments with acute and healed rupture; the percent area luminal narrowing increased with increased numbers of healed sites of previous rupture. The underlying percent luminal narrowing for acute ruptures (mean 79+/-15%) exceeded that for healed ruptures (mean 66+/-14%, P:=0.0001), and the area within the internal elastic lamina was significantly less in healed ruptures than in acute ruptures, when segments were grouped by distance from the ostium. Healed ruptures favored the accumulation of immature smooth muscle cells at repair sites, with a cellular proliferation index of 0.40+/-0.09%, significantly higher than the index at the sites of rupture (P:=0.008). CONCLUSIONS: These data provide evidence that silent plaque rupture is a form of wound healing that results in increased percent stenosis. Healed ruptures occur in arteries with less cross-sectional area luminal narrowing than acute ruptures and are a frequent finding in men who die suddenly with severe coronary atherosclerosis.


Assuntos
Doença da Artéria Coronariana/patologia , Vasos Coronários/patologia , Morte Súbita Cardíaca/patologia , Diferenciação Celular , Divisão Celular , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/epidemiologia , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Demografia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/patologia , Tamanho do Órgão , Fatores de Risco , Ruptura Espontânea , Cicatrização
15.
Nutr Metab Cardiovasc Dis ; 11 Suppl 5: 16-22, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12063771

RESUMO

AIM: Describe the relationship between serum lipoproteins and the development of atherosclerosis in young subjects aged 15-34 years, and discuss the implications for prevention of coronary heart disease. DATA SYNTHESIS: Data from gross and microscopic evaluation of aorta and coronary arterial specimens as part of the Pathobiological Determinants of Atherosclerosis in Youth (PDAY) Study demonstrates that by the age of 15 years, all subjects have atherosclerosis. Lipoprotein risk factors for coronary heart disease are associated with the extent and prevalence of gross aortic and coronary atherosclerosis and with the development of microscopic coronary plaques that have qualities consistent with clinically significant lesions. Association of lipoprotein risk factors with intermediate type atherosclerotic lesions becomes evident in subjects in their late teens, whereas associations with raised lesions become evident in subjects greater than 25 years of age, consistent with a transitional role of intermediate lesion in the formation of advanced plaques. CONCLUSIONS: Atherosclerosis begins in childhood and a significant number of young people have advanced coronary artery plaques. Early atherosclerosis is accelerated by lipoprotein risk factors. Thus, long-range prevention of atherosclerosis should begin in childhood and should include measures to control hyperlipidemia.


Assuntos
Envelhecimento/patologia , Arteriosclerose/patologia , Doença das Coronárias/prevenção & controle , Hiperlipidemias/prevenção & controle , Lipoproteínas/sangue , Adolescente , Adulto , Aorta/patologia , Colesterol/sangue , Doença das Coronárias/etiologia , Vasos Coronários/patologia , Feminino , Humanos , Hiperlipidemias/complicações , Masculino , Fatores de Risco
16.
Lipids ; 36(12): 1383-6, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11834092

RESUMO

Insulin-resistant muscle tissue contains low proportions of arachidonic acid (AA), and increased proportions of muscle AA correlate with improved insulin sensitivity. Dehydroepiandrosterone (DHEA) and AA, like the thiazolidinedione drugs that decrease insulin resistance (IR), are peroxisome proliferators. Long-chain fatty acids (FA) have been named the "one true" endogenous ligand for activating the peroxisome proliferator-activator receptor (PPAR), and DHEA has been named a "good candidate" as a naturally occurring indirect activator of PPAR. This study was conducted to determine DHEA's effects on lipid profiles of skeletal and cardiac muscle in lean and obese Zucker rats (ZR), a model of IR, type 2 diabetes mellitus, and obesity. We hypothesize that DHEA may alter long-chain FA profiles in muscle tissue of obese rats such that they more closely resemble that of the lean. In our experiments, we employed a DHEA and a pair-fed (PF) group (n = 6) for 12 lean and 12 obese ZR. For 30 d, the diet of the two DHEA groups was supplemented with 0.6% DHEA; PF groups were given the average daily calories consumed by their corresponding treatment group. Hearts and gastrocnemius muscles were assayed for phospholipid (PL), free FA, and triglyceride (TG) FA profiles. The proportion of PL AA was significantly greater in both muscle types of lean compared to obese rats. Hearts from both DHEA groups had greater PL proportions of AA and less oleic (18:1) acid than their PF controls. Likewise, 18:1 proportions were significantly lower in the gastrocnemius; however, AA proportions were not significantly different. Similar phenotypic profile differences were observed in the TG fraction of both muscle types. There were no DHEA-related TG FA profile alterations.


Assuntos
Desidroepiandrosterona/farmacologia , Coração/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Fosfolipídeos/metabolismo , Animais , Ácido Araquidônico/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Ácidos Graxos/metabolismo , Resistência à Insulina , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Ácido Oleico/metabolismo , Ratos , Ratos Zucker , Triglicerídeos/metabolismo
17.
J Natl Cancer Inst ; 92(23): 1881-8, 2000 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-11106679

RESUMO

BACKGROUND: Previous research has identified a high risk of gastric carcinoma as well as a high prevalence of cancer precursor lesions in rural populations living in the province of Nariño, Colombia, in the Andes Mountains. METHODS: A randomized, controlled chemoprevention trial was conducted in subjects with confirmed histologic diagnoses of multifocal nonmetaplastic atrophy and/or intestinal metaplasia, two precancerous lesions. Individuals were assigned to receive anti-Helicobacter pylori triple therapy and/or dietary supplementation with ascorbic acid, beta-carotene, or their corresponding placebos. Gastric biopsy specimens taken at baseline were compared with those taken at 72 months. Relative risks of progression, no change, and regression from multifocal nonmetaplastic atrophy and intestinal metaplasia were analyzed with multivariate polytomous logistic regression models to estimate treatment effects. All statistical tests were two-sided. RESULTS: All three basic interventions resulted in statistically significant increases in the rates of regression: Relative risks were 4.8 (95% confidence interval [CI] = 1.6-14.2) for anti-H. pylori treatment, 5. 1 (95% CI = 1.7-15.0) for beta-carotene treatment, and 5.0 (95% CI = 1.7-14.4) for ascorbic acid treatment in subjects with atrophy. Corresponding relative risks of regression in subjects with intestinal metaplasia were 3.1 (95% CI = 1.0-9.3), 3.4 (95% CI = 1.1-9.8), and 3.3 (95% CI = 1.1-9.5). Combinations of treatments did not statistically significantly increase the regression rates. Curing the H. pylori infection (which occurred in 74% of the treated subjects) produced a marked and statistically significant increase in the rate of regression of the precursor lesions (relative risks = 8.7 [95% CI = 2.7-28.2] for subjects with atrophy and 5.4 [95% CI = 1.7-17.6] for subjects with intestinal metaplasia). CONCLUSIONS: In the very high-risk population studied, effective anti-H. pylori treatment and dietary supplementation with antioxidant micronutrients may interfere with the precancerous process, mostly by increasing the rate of regression of cancer precursor lesions, and may be an effective strategy to prevent gastric carcinoma.


Assuntos
Antibacterianos/uso terapêutico , Antioxidantes/uso terapêutico , Ácido Ascórbico/uso terapêutico , Gastrite Atrófica/tratamento farmacológico , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Lesões Pré-Cancerosas/tratamento farmacológico , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/prevenção & controle , Estômago/patologia , beta Caroteno/uso terapêutico , Adulto , Idoso , Biópsia , Transformação Celular Neoplásica , Progressão da Doença , Quimioterapia Combinada , Feminino , Gastrite Atrófica/sangue , Gastrite Atrófica/microbiologia , Gastrite Atrófica/patologia , Infecções por Helicobacter/sangue , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/sangue , Lesões Pré-Cancerosas/patologia , Remissão Espontânea , Risco , Estômago/microbiologia , Neoplasias Gástricas/sangue , Neoplasias Gástricas/patologia , Resultado do Tratamento
18.
Am J Clin Nutr ; 72(5 Suppl): 1307S-1315S, 2000 11.
Artigo em Inglês | MEDLINE | ID: mdl-11063473

RESUMO

Atherosclerosis begins in childhood as deposits of cholesterol and its esters, referred to as fatty streaks, in the intima of large muscular arteries. In some persons and at certain arterial sites, more lipid accumulates and is covered by a fibromuscular cap to form a fibrous plaque. Further changes in fibrous plaques render them vulnerable to rupture, an event that precipitates occlusive thrombosis and clinically manifest disease (sudden cardiac death, myocardial infarction, stroke, or peripheral arterial disease). In adults, elevated non-HDL-cholesterol concentrations, low HDL-cholesterol concentrations, hypertension, smoking, diabetes, and obesity are associated with advanced atherosclerotic lesions and increased risk of clinically manifest atherosclerotic disease. Control of these risk factors is the major strategy for preventing atherosclerotic disease. To determine whether these risk factors also are associated with early atherosclerosis in young persons, we examined arteries and tissue from approximately 3000 autopsied persons aged 15-34 y who died of accidental injury, homicide, or suicide. The extent of both fatty streaks and raised lesions (fibrous plaques and other advanced lesions) in the right coronary artery and in the abdominal aorta was associated positively with non-HDL-cholesterol concentration, hypertension, impaired glucose tolerance, and obesity and associated negatively with HDL-cholesterol concentration. Atherosclerosis of the abdominal aorta also was associated positively with smoking. These observations indicate that long-range prevention of atherosclerosis and its sequelae by control of the risk factors for adult coronary artery disease should begin in adolescence and young adulthood.


Assuntos
Aorta Abdominal/patologia , Arteriosclerose/etiologia , Arteriosclerose/prevenção & controle , Desenvolvimento Infantil , Vasos Coronários/patologia , Adolescente , Adulto , Arteriosclerose/patologia , Autopsia , Criança , Humanos , Fatores de Risco , Fumar
19.
Arterioscler Thromb Vasc Biol ; 20(8): 1998-2004, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10938023

RESUMO

The raised fatty streak (fatty plaque) is the gross term for the lesion intermediate between the juvenile (flat) fatty streak and the raised lesion of atherosclerosis. We measured the percentage of intimal surface involved with flat fatty streaks, raised fatty streaks, and raised lesions in the aortas and right coronary arteries of 2876 autopsied persons aged 15 through 34 years who died of external causes. Raised fatty streaks were present in the abdominal aortas of approximately 20% of 15- to 19-year-old subjects, and this percentage increased to approximately 40% for 30- to 34-year-old subjects. Raised fatty streaks were present in the right coronary arteries of approximately 10% of 15- to 19-year-old subjects, and this percentage increased to approximately 30% for 30- to 34-year-old subjects. The percent intimal surface involved with raised fatty streaks increased with age in both arteries and was associated with high non-high density lipoprotein (HDL) and low HDL cholesterol concentrations in the abdominal aorta and right coronary artery, with hypertension in the abdominal aorta, with obesity in the right coronary artery of men, and with impaired glucose tolerance in the right coronary artery. Associations of risk factors with raised fatty streaks became evident in subjects in their late teens, whereas associations of risk factors with raised lesions became evident in subjects aged >25 years. These results are consistent with the putative transitional role of raised fatty streaks and show that coronary heart disease risk factors accelerate atherogenesis in the second decade of life. Thus, long-range prevention of atherosclerosis should begin in childhood or adolescence.


Assuntos
Arteriosclerose/patologia , Doença das Coronárias/patologia , Adolescente , Adulto , Envelhecimento , Aorta Abdominal/química , Aorta Abdominal/patologia , Aorta Torácica/química , Aorta Torácica/patologia , Colesterol/análise , HDL-Colesterol/análise , Vasos Coronários/química , Vasos Coronários/patologia , Feminino , Intolerância à Glucose , Humanos , Hipertensão/complicações , Masculino , Obesidade/complicações , Fatores de Risco , Fumar/efeitos adversos
20.
J La State Med Soc ; 152(6): 296-301, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10935370

RESUMO

In 1985, investigators organized a multi-center study, Pathobiological Determinants of Atherosclerosis in Youth (PDAY), to examine the relationships of cardiovascular risk factors to atherosclerosis involving more than 3,000 young persons 15 through 34 years of age who died of external causes. Reports from the PDAY group confirmed that atherosclerosis begins in the teens and showed that the progression of the lesions is strongly influenced by the same risk factors that predict risk of clinically manifest coronary disease in middle-aged adults. The results emphasize the need for early and aggressive control of all risk factors in young persons for long-range prevention of coronary heart disease and related diseases. Recent funding by the Louisiana Cancer and Lung Trust Fund (LCLTF) has assisted Pathology at Louisiana State University Health Sciences Center (LSUHSC) in the following objectives: (1) maintaining this national research resources; (2) making the unique specimens available to interested investigators; and (3) continuing support for studies at LSUHSC which investigate the effects of smoking on the development of atherosclerotic lesions.


Assuntos
Arteriosclerose/patologia , Doença das Coronárias/prevenção & controle , Serviços de Informação , Adolescente , Adulto , Arteriosclerose/prevenção & controle , Progressão da Doença , Humanos , Louisiana , Pesquisa , Fatores de Risco , Estados Unidos
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