Potential vertebrate reservoir hosts and invertebrate vectors of Anaplasma marginale and A. phagocytophilum in central Spain

Organisms in the genus Anaplasma are obligate intracellular pathogens that multiply in both vertebrate and invertebrate hosts. The type species, A. marginale, causes bovine anaplasmosis and only infects ticks and ruminants. A. phagocytophilum causes human and animal granulocytic anaplasmosis, and genetically closely related strains show a wide host range, including ticks, ruminants, rodents, equids, canids, birds, and humans. Recent reports demonstrated that A. marginale and A. phagocytophilum co-exist in geographic areas and that concurrent infections occur in ruminants and ticks. In this study, we characterized A. marginale and A. phagocytophilum infections in wild and domestic animals, and ticks collected in central Spain by serology, PCR, and sequence of 16S rRNA genotypes. Species tested included humans, cattle, dogs, rodents, Iberian red deer, European wild boar, birds, and ticks. Species of hematophagous Diptera were analyzed as potential mechanical vectors of Anaplasma spp. A. marginale was detected in tabanids, ticks, cattle, and deer, while A. phagocytophilum was detected in ticks, deer, cattle, and birds. Concurrent infections of the two Anaplasma were found in cattle and deer. These results illustrate the complexity of the epizootiology of A. marginale and A. phagocytophilum in regions where both pathogens co-exist and share common reservoir hosts and vectors. The increasing contact between wildlife, domestic animals, and human populations increases the risk of outbreaks of human and bovine anaplasmosis, and the difficulty of implementing surveillance and control measures.     

Role of mercury toxicity in hypertension, cardiovascular disease, and stroke

Mercury has a high affinity for sulfhydryl groups, inactivating numerous enzymatic reactions, amino acids, and sulfur-containing antioxidants (N-acetyl-L-cysteine, alpha-lipoic acid, L-glutathione), with subsequent decreased oxidant defense and increased oxidative stress. Mercury binds to metallothionein and substitute for zinc, copper, and other trace metals, reducing the effectiveness of metalloenzymes. Mercury induces mitochondrial dysfunction with reduction in adenosine triphosphate, depletion of glutathione, and increased lipid peroxidation. Increased oxidative stress and reduced oxidative defense are common. Selenium and fish containing omega-3 fatty acids antagonize mercury toxicity. The overall vascular effects of mercury include increased oxidative stress and inflammation, reduced oxidative defense, thrombosis, vascular smooth muscle dysfunction, endothelial dysfunction, dyslipidemia, and immune and mitochondrial dysfunction. The clinical consequences of mercury toxicity include hypertension, coronary heart disease, myocardial infarction, cardiac arrhythmias, reduced heart rate variability, increased carotid intima-media thickness and carotid artery obstruction, cerebrovascular accident, generalized atherosclerosis, and renal dysfunction, insufficiency, and proteinuria. Pathological, biochemical, and functional medicine correlations are significant and logical. Mercury diminishes the protective effect of fish and omega-3 fatty acids. Mercury inactivates catecholaminei-0-methyl transferase, which increases serum and urinary epinephrine, norepinephrine, and dopamine. This effect will increase blood pressure and may be a clinical clue to mercury-induced heavy metal toxicity. Mercury toxicity should be evaluated in any patient with hypertension, coronary heart disease, cerebral vascular disease, cerebrovascular accident, or other vascular disease. Specific testing for acute and chronic toxicity and total body burden using hair, toenail, urine, and serum should be performed.     

Evolution of genome-phenome diversity under environmental stress

The genomic era revolutionized evolutionary biology. The enigma of genotypic-phenotypic diversity and biodiversity evolution of genes, genomes, phenomes, and biomes, reviewed here, was central in the research program of the Institute of Evolution, University of Haifa, since 1975. We explored the following questions. (i) How much of the genomic and phenomic diversity in nature is adaptive and processed by natural selection? (ii) What is the origin and evolution of adaptation and speciation processes under spatiotemporal variables and stressful macrogeographic and microgeographic environments? We advanced ecological genetics into ecological genomics and analyzed globally ecological, demographic, and life history variables in 1,200 diverse species across life, thousands of populations, and tens of thousands of individuals tested mostly for allozyme and partly for DNA diversity. Likewise, we tested thermal, chemical, climatic, and biotic stresses in several model organisms. Recently, we introduced genetic maps and quantitative trait loci to elucidate the genetic basis of adaptation and speciation. The genome-phenome holistic model was deciphered by the global regressive, progressive, and convergent evolution of subterranean mammals. Our results indicate abundant genotypic and phenotypic diversity in nature. The organization and evolution of molecular and organismal diversity in nature at global, regional, and local scales are nonrandom and structured; display regularities across life; and are positively correlated with, and partly predictable by, abiotic and biotic environmental heterogeneity and stress. Biodiversity evolution, even in small isolated populations, is primarily driven by natural selection, including diversifying, balancing, cyclical, and purifying selective regimes, interacting with, but ultimately overriding, the effects of mutation, migration, and stochasticity.     

Identification and distribution of New World Leishmania species characterized by serodeme analysis using monoclonal antibodies

Five hundred thirty stocks of Leishmania isolated from human and domestic and wild reservoir hosts, representing a wide geographic distribution of endemic foci of American cutaneous (ACL) and visceral leishmaniases (AVL) were characterized and identified at species and/or subspecies levels based on their reactivity to a cross-panel of specific monoclonal antibodies using a radioimmune binding assay. This study confirms and extends our preliminary results on the high specificity of some of these monoclonals for the L. braziliensis, L. mexicana, and L. donovani complexes. This study also demonstrates the relative stability of these molecular markers and the general usefulness of the method for parasite identification. Two hundred ninety-two of 420 isolates of ACL were classified as members of the L. braziliensis complex. Two hundred twenty-seven were L. b. braziliensis; these showed the widest geographical distribution (Brazil: Amazonas, Bahia, Ceara, Espirito Santo, Goias, Minas Gerais, Para, Paraiba, Rio de Janeiro, and Sao Paulo; Honduras: Santa Barbara and Yoko; Peru: Ancash, Piura, and Ucayali; and Venezuela: Cojedes, Distrito Federal, Lara, Portuguesa, Vale Hondo, Yaracuy, and Zulia). Forty-one stocks were identified as L. b. guyanensis (from North Brazil: Amazonas, Amapa, Para, and Rondonia). Twenty-one stocks were identified as L. b. panamensis (from Costa Rica: Alajuela, Guanacasten, Limon, Puntarenas, and San Jose; and Honduras: El Paraiso, and Olancho). Out of 128 isolates classified as members of the L. mexicana complex, 74 were differentiated as L. m. amazonensis (from Bolivia; Brazil: Amazonas, Bahia, Ceara, Goias, Maranhao, Mato Grosso do Norte, and Para; Peru: Pasco Forest and Van Humboldt; and Venezuela: Carabobo, Guarico, and Merida). Forty-four stocks were identified as L. m. venezuelensis (from Venezuela: Lara). Six stocks were L. m. mexicana (from Belize; and Mexico: Campeche [corrected] and Quintana Roo, Yucatan). One hundred ten isolates from AVL were identified as L. donovani chagasi (from Brazil: Bahia, Ceara, Maranhao, Minas Gerais, Mato Grosso do Sul, Piaui, Rio de Janeiro, and Sergipe; and Honduras: Valle). The implications of these results with respect to both the clinical and epidemiological data (including the detection of seven unusual characterized stocks) are discussed.     

Hypothyroidism

Hypothyroidism is common, potentially serious, often clinically overlooked, readily diagnosed by laboratory testing, and eminently treatable. The condition is particularly prevalent in older women, in whom autoimmune thyroiditis is common. Other important causes include congenital thyroid disorders, previous thyroid surgery and irradiation, drugs such as lithium carbonate and amiodarone, and pituitary and hypothalamic disorders. Worldwide, dietary iodine deficiency remains an important cause. Hypothyroidism can present with nonspecific constitutional and neuropsychiatric complaints, or with hypercholesterolaemia, hyponatraemia, hyperprolactinaemia, or hyperhomocysteinaemia. Severe untreated hypothyroidism can lead to heart failure, psychosis, and coma. Although these manifestations are neither specific nor sensitive, the diagnosis is confirmed or excluded by measurements of serum thyrotropin and free thyroxine. Thyroxine replacement therapy is highly effective and safe, but suboptimal dosing is common in clinical practice. Patient noncompliance, drug interactions, and pregnancy can lead to inadequate treatment. Iatrogenic thyrotoxicosis can cause symptoms, and, even when mild, provoke atrial fibrillation and osteoporosis. We summarise present understanding of the history, epidemiology, pathophysiology, and clinical diagnosis and management of hypothyroidism.     

BOOKS

Book reviewed in this article: Molecular and Cellular Aspects of Erythropoietin and Erythropoiesis. NATO AS1 Series: Cell Biology, vol. 8, ed. Rich IN. Progress in Clinical and Biological Research, volume 251. Developmental Control of Globin Gene Expression, eds. Blood Transfusion in Clinical Medicine. Eighth edition, eds. Molliaon PL, Engelfriet CP & Contreras M. Immunobiology of Cancer and AIDS. Etiology, diagnosis and management, eds. Nieburgs HE & Bekesi JG. Thalassemia: Pathophysiology and Management. Part B, eds. Fucharoen S, Rowley PT & Paul NW. Atlas of Blood Cells. Function and Pathology, eds. Zucker-Franklin D, Greaves MF, Grossi CE & Marmont AM. Edi. Ermes, Milano. Genotypic, phenotypic and functional aspects of hematopoiesis, eds. Grignani F, Martelli MF & Mason DY. Recent Advances and Future Directions in Bone Marrow Transplantation. Experimental Hematology Today -1987, eds. Chronic Lymphocytic Leukemia, eds. Polliack A & Catovsky D. Harwood Biological Response Modifiers and Cancer Therapy, ed. Chiao JW. Human Retroviruses, Cancer, and AIDS. Approaches to prevention and therapy.     

双氢青蒿素抗日本血吸虫作用的体内实验观察

目的观察不同发育阶段日本血吸虫对双氢青蒿素的敏感性,探索双氢青蒿素抗日本血吸虫的效果。方法采用尾蚴腹部贴片法感染小鼠,每鼠感染日本血吸虫尾蚴40条;在血吸虫不同发育阶段灌服用药,于感染后50 d解剖小鼠,收集成虫,计算减虫率和减雌率。①在小鼠感染后2 h,3、5、7、10、14、18、21、28 d和35 d灌服双氢青蒿素（300 mg/kg）,观察双氢青蒿素对不同发育阶段血吸虫的作用效果。②以不同剂量双氢青蒿素分别给感染后7 d或35 d的小鼠用药,观察双氢青蒿素抗日本血吸虫作用的量-效关系。③以不同药物剂量分别在感染后第7天和第35天给药（共2次）,观察双氢青蒿素对日本血吸虫的作用效果。结果300 mg/kg双氢青蒿素一次灌服用药对7 d龄童虫和35 d龄成虫有明显杀灭作用,减虫率分别为64.81%和60.47%,减雌率分别为73.81%和90.48%。以200、300、400 mg/kg和600 mg/kg双氢青蒿素治疗感染后7 d小鼠,减虫率分别为46.84%、60.63%、59.55%和60.21%,减雌率分别为59.73%、72.29%、72.58%和76.61%;治疗感染后35 d小鼠,减虫率分别为47.23%、62.33%、76.31%和83.63%,减雌率分别为59.73%、89.36%、89.65%和93.96%;在感染后第7天和第35天共治疗2次,减虫率分别为58.16%、82.66%、83.42%和83.79%,减雌率分别为68.69%、90.43%、93.74%和94.63%。结论双氢青蒿素具有一定的抗日本血吸虫作用,对7 d童虫和35 d成虫较为敏感。     

Functions of the fibrinolytic system in human Ito cells and its control by basic fibroblast and platelet-derived growth factor

During liver fibrogenesis, hepatic stellate cells (HSC) proliferate and migrate under the influence of growth factors, including platelet-derived growth factor (PDGF) and basic-fibroblast growth factor (b-FGF). The plasminogen activation system regulates extracellular matrix (ECM) catabolism and cell movement. We evaluated the expression and biological functions of the plasminogen activation system in human HSC and its interaction with PDGF and b-FGF. Urokinase-plasminogen activator receptors (u-PAR) were measured by radioligand binding, cell cross-linking, immunoassay, and RNAse protection assay. u-PA and plasminogen activator inhibitors (PAIs) expression and activities were analyzed by zymography, immunoassay, and RNase protection assay. Cell migration and proliferation, studied in Boyden chambers and by microscopic counting, were evaluated after the addition of PDGF, b-FGF, and blockade with anti-u-PA, anti-u-PAR antibodies, and antisense oligodeoxynucleotides (aODN) against u-PAR mRNA. We have shown that HSC produce u-PAR, u-PA, and PAI-1. PDGF and b-FGF up-regulate u-PA and u-PAR, but not PAI-1, and exogenous addition of u-PA stimulates HSC proliferation, chemotaxis, and chemoinvasion. Inhibition of u-PA/u-PAR with antibodies against u-PA or u-PAR and with u-PAR aODN inhibit the proliferative, chemotactic, and chemoinvasive activity of PDGF and b-FGF. These findings indicate that u-PA and u-PAR are required for the mitogenic and chemoinvasive activity of PDGF and b-FGF on HSC.     

Synergistic Pathogenicity by Coinfection and Sequential Infection with NADC30-like PRRSV and PCV2 in Post-Weaned Pigs

Porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus (PCVs) are two major viruses that affect pigs. Coinfections between PRRSV and PCV2 are frequently reported in most outbreaks, with clinical presentations involving dyspnea, fever, reduced feed intake, weight loss, and death in fattening pigs. The NADC30-like PRRSV and PCV2d are the main circulating virus strains found in China. This study determines the impact of NADC30-like PRRSV and PCV2d mono-infection and coinfection on the immune system, organ pathology, and viral shedding in five-week-old post-weaned pigs. Pigs were randomly divided into six groups: PBS, PRRSV, PCV2, PRRSV-PCV2 coinfection (co), and PRRSV-PCV2 or PCV2-PRRSV sequential infections. Fever, dyspnea, decreased feed intake, weight loss, and pig deaths occurred in groups infected with PRRSV, Co-PRRSV-PCV2, and PRRSV-PCV2. The viral load was higher in Co-PRRSV-PCV2, PRRSV-PCV2, and PCV2-PRRSV than those mono-infected with PRRSV or PCV2. Additionally, cytokines (IFN-γ, TNF-α, IL-4, and IL-10) produced by pigs under Co-PRRSV-PCV2 and PRRSV-PCV2 groups were more intense than the other groups. Necropsy findings showed hemorrhage, emphysema, and pulmonary adhesions in the lungs of pigs infected with PRRSV. Smaller alveoli and widened lung interstitium were found in the Co-PRRSV-PCV2 and PRRSV-PCV2 groups. In conclusion, PRRSV and PCV2 coinfection and sequential infection significantly increased viral pathogenicity and cytokine responses, resulting in severe clinical signs, lung pathology, and death.     

武汉市血吸虫病控制达标考核结果评价

目的考核2007年武汉市血吸虫病控制达标情况。方法按照血吸虫病控制和消灭的国家标准,对武汉市洪山、蔡甸、汉南、黄陂、江夏、东西湖和江岸等7个区开展人畜查病和螺情调查。结果20042006年全市居民血吸虫感染率分别为3.06%、0.93%和0.56%,急性血吸虫病病人数分别为14、10和4例;耕牛感染率分别为0.88%、1.39%和0.67%;有螺面积分别为1 351.301、1 343.916和1 341.829万^m2。2007年,洪山、蔡甸、汉南、黄陂和江夏等5个疫情控制考核区居民血吸虫感染率0.67%,耕牛感染率0.69%。东西湖和江岸2个传播控制考核区居民血检阳性率分别为3.47%和1.71%;粪检未见阳性病人和耕牛;螺点调查未见感染性钉螺。结论2004年以来武汉市血吸虫病疫情呈逐年下降趋势,洪山、蔡甸、汉南、黄陂和江夏等5个区达到血吸虫病疫情控制标准,东西湖和江岸2个区达到血吸虫病传播控制标准。     

Differences in breast cancer stage,treatment, and survival by race and ethnicity

BACKGROUND: In the United States, black and Hispanic white women with breast cancer present with more advanced stages and have poorer survival rates than non-Hispanic whites, whereas Asians and Pacific Islanders do not. However, Asians and Pacific Islanders and Hispanic whites are heterogeneous populations, and few studies have evaluated breast cancer stage, treatments, and mortality rates for subgroups of these populations. METHODS: Using data from 11 population-based tumor registries that participate in the Surveillance, Epidemiology, and End Results Program, we conducted a retrospective cohort study to evaluate the relationship between race and ethnicity and breast cancer stage, treatments, and mortality rates. The cohort of 124,934 women diagnosed as having a first primary invasive breast carcinoma between January 1, 1992, and December 31, 1998, included 97,999 non-Hispanic whites, 10,560 blacks, 322 American Indians, 8834 Asians and Pacific Islanders, and 7219 Hispanic whites. RESULTS: Relative to non-Hispanic whites, blacks, American Indians, Hawaiians, Indians and Pakistanis, Mexicans, South and Central Americans, and Puerto Ricans had 1.4- to 3.6-fold greater risks of presenting with stage IV breast cancer. Blacks, Mexicans, and Puerto Ricans were 20% to 50% more likely to receive or elect a first course of surgical and radiation treatment not meeting the 2000 National Comprehensive Cancer Network standards. In addition, blacks, American Indians, Hawaiians, Vietnamese, Mexicans, South and Central Americans, and Puerto Ricans had 20% to 200% greater risks of mortality after a breast cancer diagnosis. CONCLUSIONS: Differences in breast cancer stage, treatments, and mortality rates are present by race and ethnicity. Breast cancer survival may be improved by targeting factors, particularly socioeconomic factors, that underlie these differences.     

Effects of cyromazin and methoprene on the developmental stages of Anopheles dirus, Aedes aegypti and Culex quinquefasciatus (Diptera : Culicidae)

The effects of two chemical compounds, cyromazin and methoprene, on the developmental stages of Anopheles dirus, Aedes aegypti and Culex quinquefasciatus were investigated under laboratory conditions, with the mean temperature of 24 degrees +/- 1 degree C and the relative humidity at 65-75%. Both compounds were tested against the second, third and fourth instar larvae. The concentrations of cyromazin used for An. dirus and Cx. quinquefasciatus ranged from 0.0008 to 0.5 mg/l; and for Ae. aegypti from 0.004 to 2.5 mg/l. The concentrations of methoprene used for An. dirus, Ae. aegypti and Cx. quinquefasciatus ranged from 0.00016 to 0.1 mg/l. The mortality rates were found to be relatively high in larval and pupal stages when treated with cyromazin and methoprene. The primary toxic effects of cyromazin were on the second stage larvae. The LC50 values for cyromazin on the second, third and fourth stage larvae were, respectively, 0.0027, 0.0042 and 0.0114 mg/l for An. dirus, and 0.1662, 0.2307 and 0.3005 mg/l for Ae. aegypti. Cx. quinquefasciatus was the most sensitive species to cyromazin with LC50 values for second, third and fourth stage larvae of 0.0015, 0.0068 and 0.0130 mg/l, respectively. The primary toxic effects of methoprene were in the fourth stage larvae. The LC50 values for methoprene on the second, third and fourth stage larvae were, respectively, 0.0110, 0.0041 and 0.0022 mg/l for An. dirus, and 0.0077, 0.0034 and 0.0025 mg/l for Ae. aegypti. Cx. quinquefasciatus was the most sensitive species to methoprene, with LC50 values for second, third and fourth stage larvae of 0.0013, 0.0008 and 0.0006 mg/l, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Evaluation of immunochromatography method for rapid detection of Shigatoxin

The Shigatoxin detection kit based on the immunochromatography system is commercially available. To obtain the identification result rapidly, we devised the improved method (ICG-Imp) replaced to an original method (ICG). Modification provided that Shigatoxins extracted directly from the strains grown on TSI medium without centrifugation. ICG-Imp was compared with ICG, RPLA and PCR. Comparing with RPLA, the sensitivity, specificity, and concordance rate of Shigatoxin 1 showed 77.5, 100 and 90.5%, respectively on ICG, 93.8, 100 and 97.4%, respectively on ICG-Imp, and 100, 99.1 and 99.5%, respectively on PCR. On the other hand, the patterns of Shigatoxin 2 showed 95.3, 100 and 96.3%, respectively on ICG, 100, 100, and 100%, respectively on ICG-Imp, and 100, 100 and 100%, respectively on PCR. The time required from TSI medium to the final result are 24 h, 30-60 min, 48 h, and 6 h, respectively by ICG, ICG-Imp, RPLA, and PCR. It seems that the ICG-Imp is recommended for the identification by means of the accuracy and rapidness.     

Comparative studies on several biochemical indices of Anopheles anthropophagus and Anopheles sinensis

Proteins, sugars and esterase isoenzymes of An. anthropophagus and An. sinensis were compared by IEF and two dimensional gel electrophoresis. The results show that there are some differences in the electrophoretic patterns between An. anthropophagus and An. sinensis. The glycoprotein, lipid protein, glycolipidprotein, protein, polysaccharide and esterase isoenzymes showed 10, 0, 6, 14, 2 and 13 bands in An. anthropophagus; 10, 1, 5, 16, 3 and 15 in An. sinensis. There exist 234 and 240 polypeptide spots in An. anthropophagus and in An. sinensis, respectively, altogether 27.8% of polypeptide spots being different.     

Agreement between self-report of disease diagnoses and medical record validation in disabled older women: factors that modify agreement

OBJECTIVES: To determine the agreement between self-report of chronic disease and validated evidence of disease using multiple ascertainment methods and to assess effects of cognition, education, age, and comorbidity. DESIGN: Cross-sectional analysis. SETTING: Community Baltimore, Maryland. PARTICIPANTS: One thousand two community-dwelling disabled women aged 65 and older. MEASUREMENTS: Kappa statistics were calculated to determine the relationship between self-report of 14 diseases and standardized algorithms. Analyses were stratified using Mini-Mental State Examination score, education, number of chronic diseases, and age. RESULTS: Kappa was excellent for hip fracture (HF), Parkinson's disease (PD), diabetes mellitus (DM), cancer, stroke, and disc disease (DD); fair to good for angina pectoris, congestive heart failure, and myocardial infarction; and poor for peripheral arterial disease, spinal stenosis, osteoporosis, arthritis, and lung disease. Overall, kappa decreased with decreasing cognition and education, increasing age, and four or more diseases. CONCLUSION: In disabled older women, self-report of physician diagnosis of HF, PD, DM, cancer, stroke, and DD appears valid. In general, increasing comorbidity and age and decreasing cognition and education do not reduce validity for diseases where agreement was excellent overall.     

幽门螺杆菌5种候选疫苗抗原基因的克隆、表达及抗原性的鉴定

目的:构建含人Hpylori5种候选疫苗抗原Lpp20,HspA,UreaseA,CagA,UreaseB的编码基因的重组质粒并研究其抗原性.方法:应用PCR技术从Hpylori染色体中扩增编码Lpp20,HspA,UreaseA,CagA,UreaseB的基因片段,将其T-A克隆和测序,并与GenBank公布的其他Hpylori菌株基因序列比较,再将目的基因克隆至融合表达载体pGEX-4T-1上中进行表达,用GST亲和层析对其进行纯化,纯化产物用于对29株小鼠抗Hpylori-全菌单克隆抗体(mAb)的鉴定及与Hpylori感染患者血清进行Westernblot分析.结果:扩增的Lpp20,HspA,UreaseA,CagA,UreaseB基因全长分别为528bp,351bp,675bp,855bp,1704bp(GenBank登录号分别为DQ106902,DQ141574,DQ141577,DQ141575,DQ141576),与GenBank公布的其他菌株的核酸序列的同源性在95%-99%,表达Lpp20,HspA,UreaseA,CagA,UreaseB融合蛋白的相对分子质量分别约为48000,41000,52000,60000,91000Da,29株小鼠抗Hpylori全菌mAb中针对Lpp20,HspA,UreaseA,CagA,UreaseB抗原的分别为4,5,5,1,6株,5种抗原的纯化产物均可被Hpylori感染患者血清特异性识别.结论:重组表达的Lpp20,HspA,UreaseA,CagA,UreaseB均具有较好的抗原性.     

Nutritional contributors to cardiovascular disease in the elderly

Cardiovascular disease, so common in the elderly, has become an urgent public health concern. Major contributing factors include hypertension, dyslipidemia, impaired glucose tolerance, physical indolence, and cigarette smoking. Diet plays a major role in atherogenesis by its influence in blood lipids, blood pressure, and glucose tolerance, although its impact in the elderly is speculative owing to a paucity of direct evidence. But a rationale exists. Most cardiovascular risk factors are more prevalent in the elderly than in the young adult. The rise in blood pressure and blood lipids with advancing age is not inevitable. Diet may contribute to hypertension through an excess of calories, saturated fat, cholesterol, or salt and a deficiency of potassium, calcium, and magnesium. Antiatherogenic diets low in saturated fat and cholesterol, rich in fiber, and with substitution of polyunsaturated fat and restricted calories tend to normalize serum lipids and to cause lesions to involute. Emphasis on vegetable protein and fiber-rich food has merit because they provide more fiber, polyunsaturated fatty acids, magnesium, selenium, complex carbohydrate, potassium, and copper, and less cholesterol, saturated fat, and sodium. The recommended fat-modified diets are adequate in protein, vitamins, and minerals and need not be deficient in any nutrient or economically nonfeasible. The accelerating decline in cardiovascular mortality, which has included the elderly, indicates that such disease is controllable and not inevitable, even in the elderly. The decrease has occurred concurrently with reduced consumption of saturated fat and cholesterol, increased use of vegetable oils, and improved levels of cardiovascular risk factors.     

钉螺血淋巴细胞及其功能的研究

目的 研究获取钉螺血淋巴细胞的方法, 观察其形态结构, 研究其免疫等相关功能。 方法 参照外周淋巴器官中淋巴细胞的悬浮收集法, 获取钉螺血淋巴细胞, 经Giemsa染色后显微镜观察其形态。 血淋巴细胞经结晶紫染色后分别计数悬浮法、传统压片法及针刺法获取的血淋巴细胞数, 并进行方差分析和Dunnett?鄄t检验。取冻融的血淋巴细胞上清进行免疫沉淀、抑菌、吞噬杀菌实验。十二烷基磺酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）分析血淋巴细胞蛋白组份相对分子质量（Mr）。 结果 钉螺血淋巴细胞分为圆形有丝状伪足、嗜酸性圆形无丝状伪足、嗜碱性圆形无丝状伪足和梭形细胞4种形态, 平均直径依次约为 10.93、6.13、6.08及11.06 μm, 各约占细胞总数的 50%、 30%、 5% 及15%。每只钉螺悬浮法、传统压片法及针刺法获取的血淋巴细胞均数分别为1.50、0.66及0.03万/ml。悬浮法与传统压片法、与针刺法差异有统计学意义（F=281.47, P<0.01）。进一步Dunnett-t检验, 悬浮法与压片法、与针刺法的血淋巴细胞总体均数差异有统计学意义（t₁=15.67, t₂=24.50, 两组P<0.01）。血淋巴上清与日本血吸虫虫卵可溶性抗原（SEA）反应出现絮状沉淀, 抑菌试验对金黄色葡萄球菌和大肠埃希菌出现明显的抑菌圈, 血淋巴细胞对白色念珠菌的吞噬率和杀菌率分别为86%和46%。血淋巴细胞蛋白组份相对分子质量约为Mr 112 300、 107 100、 97 200、 73 500、 60 000及12 000。 结论 悬浮法可获得大量钉螺血淋巴细胞, 其具有沉淀SEA、抑制金黄色葡萄球菌和大肠埃希菌生长, 以及吞噬杀灭白色念珠菌等免疫功能。