The Epidemiology of Thyroid Cancer in Los Angeles County

More than 300 new cases of thyroid cancer are diagnosed in Los Angeles County every year. The age-adjusted annual incidence rates of this disease for all races combined are 2.4 for males and 6.1 for females. Rates for women are more than twice rates for men in each major ethnic group. Blacks of both sexes have the lowest rates; Japanese, Chinese, other Asians and Spanish-surnamed whites all have rates that are as high as or higher than rates among non-Spanish-surnamed whites. Other demographic patterns include the excess of thyroid cancer among Jewish residents of Los Angeles.There have been an increase in thyroid cancer incidence and a decline in mortality for this disease in the United States over the past several decades. Several possible explanations can be made for these trends. Also, the risk factors for thyroid cancer deserve review.     

Genetic Characterization and Epidemiology of Helicobacters in Non‐domestic Animals

Background: Novel helicobacter infections and associated disease are being recognized with increasing frequency in animals and people. Yet, the pervasiveness of infection in distantly related animal taxa, genetic diversity of helicobacters, and their transmissability are not known. Aim: To better understand the ecology of helicobacters, we did a PCR survey and epidemiologic analysis of 154 captive or wild vertebrate taxa originating from 6 continents. Materials and Methods: One hundred twenty nine helicobacter 16s rRNA gene segments were amplified by PCR and sequenced from ninety‐three mammalian, reptilian, avian, or amphibian host species. Prevalence estimates were generated, and univariate logistic regression analyses were used to explore relationships between infection status and the health and characteristics of the 220 individual animals. Results: One hundred and nineteen novel helicobacter DNA sequences were found. No significant relationship between infection and host health was found; however, multi‐infection or infections with particular genotypes were associated with mild clinical signs. Phylogenetic and genetic comparisons of helicobacters suggested prolonged co‐adaptation and niche‐associated divergence as well as periodic inter‐species transmission. Conclusion: The genus Helicobacter should accordingly be viewed as a collection of hundreds of organisms that have colonized most tetrapod taxa and have the potential to expand into new hosts as contact among animals and between animals and people increases.     

A Systematic Review of the Epidemiology of Echinococcosis in Domestic and Wild Animals

Background

Human echinococcosis is a neglected zoonosis caused by parasites of the genus Echinococcus. The most frequent clinical forms of echinococcosis, cystic echinococcosis (CE) and alveolar echinococcosis (AE), are responsible for a substantial health and economic burden, particularly to low-income societies. Quantitative epidemiology can provide important information to improve the understanding of parasite transmission and hence is an important part of efforts to control this disease. The purpose of this review is to give an insight on factors associated with echinococcosis in animal hosts by summarising significant results reported from epidemiological studies identified through a systematic search.

Methodology and Principal Findings

The systematic search was conducted mainly in electronic databases but a few additional records were obtained from other sources. Retrieved entries were examined in order to identify available peer-reviewed epidemiological studies that found significant risk factors for infection using associative statistical methods. One hundred studies met the eligibility criteria and were suitable for data extraction. Epidemiological factors associated with increased risk of E. granulosus infection in dogs included feeding with raw viscera, possibility of scavenging dead animals, lack of anthelmintic treatment and owners'' poor health education and indicators of poverty. Key factors associated with E. granulosus infection in intermediate hosts were related to the hosts'' age and the intensity of environmental contamination with parasite eggs. E. multilocularis transmission dynamics in animal hosts depended on the interaction of several ecological factors, such as hosts'' population densities, host-prey interactions, landscape characteristics, climate conditions and human-related activities.

Conclusions/Significance

Results derived from epidemiological studies provide a better understanding of the behavioural, biological and ecological factors involved in the transmission of this parasite and hence can aid in the design of more effective control strategies.     

The Epidemiology of Neuroendocrine Tumors in Taiwan: A Nation-Wide Cancer Registry-Based Study

Background

The epidemiology of neuroendocrine tumors (NETs) is not well illustrated, particularly for Asian countries.

Methods

The age-standardized incidence rates and observed survival rates of NETs diagnosed in Taiwan from January 1, 1996 to December 31, 2008 were calculated using data of the Taiwan Cancer Registry (TCR) and compared to those of the Norwegian Registry of Cancer (NRC) and the US Surveillance, Epidemiology, and End Results (SEER) program.

Results

During the study period, a total of 2,187 NET cases were diagnosed in Taiwan, with 62% males and a mean age of 57.9 years-old. The age-standardized incidence rate of NETs increased from 0.30 per 100,000 in 1996 to 1.51 per 100,000 in 2008. The most common primary sites were rectum (25.4%), lung and bronchus (20%) and stomach (7.4%). The 5-year observed survival was 50.4% for all NETs (43.4% for men and 61.8% for women, P<0.0001). The best 5-year observed survivals for NETs by sites were rectum (80.9%), appendix (75.7%), and breast (64.8%).

Conclusions

Compared to the data of Norway and the US, the age-standardized incidence rate of NETs in Taiwan is lower and the major primary sites are different, whereas the long-term outcome is similar. More studies on the pathogenesis of NETs are warranted to devise preventive strategies and improve treatment outcomes for NETs.     

The Use of Naturally Occurring Cancer in Domestic Animals for Research into Human Cancer: General Considerations and a Review of Canine Skeletal Osteosarcoma

For many years, research into human cancer has concentrated on human patients and on artificially induced neoplasms in inbred murine hosts. Cancer, however, affects a great variety of mammals, particularly those that have been domesticated. Suchf naturally occurring neoplasms are common in dogs, cats, cattle, horses, etc., and offer fertile ground for studies relating to epidemiologyf, etiology, immunobiology, and therapy. Canine osteosarcoma is described in detail. The clinicopathologic features of this canine tumor closely approximate that of human osteosarcoma and thus make canine osteosarcoma an invaluable comparative model. Canine osteosarcoma and other naturally occurring tumors lie intermediate between the mouse models and human cancer. The use of these veterinary models in the future fabric of cancer research will broaden its base and will influence our conceptual approach to research and clinical options.     

动物转基因研究中的技术方法

转基因动物研究的深入为生物学的发展起到了巨大的推动作用。转基因新技术的不断出现,推动了转基因动物的发展。介绍了几种哺乳动物转基因研究中常见的方法,包括原核显微注射法、逆转录病毒感染法、胚胎干细胞介导法、生殖细胞介导法、基因打靶以及新的比较有应用前景的方法,如PiggyBac、iPS,锌指核酸酶法,并且分别对每种方法的优缺点进行了总结归纳。     

动物辨别亲属的机制

亲缘识别在动物界中是很普遍的现象。不同的动物有不同的手段识别亲属。亲缘辨别的机制主要有空间识别机制,熟悉机制,表形匹配和识别等位基因4种机制,有的动物只有一种机制起作用,有的则是两种机制同时共存或不同时期不同机制。此外,还概述了亲缘辨别的一些功能。     

转基因动物在生物制药工业中的应用

简要论述了转基因动物的概念、制作方法及应用领域,回顾了转基因动物技术的发展及现状,分析了转基因动物与克隆动物的区别.就转基因动物在制药工业和生物医药领域中的国内外研究与开发应用情况进行了阐述,同时展望了转基因动物制药的发展前景及对社会的影响.     

A Review of the Epidemiology of Trichloroethylene and Kidney Cancer

The occupational epidemiological studies of trichloroethylene (TCE) exposure and kidney cancer are reviewed. Seven occupational cohort studies, conducted in the U.S., Finland, and Sweden involving over 130,000 workers, do not report statistically increased risks of kidney cancer among TCE-exposed workers. These studies were based on well-defined cohorts and exposure assessments involving urine biomonitoring or some type of job exposure matrix. In contrast, two German studies reported eight- to eleven-fold increased risks for renal cancer among TCE-exposed workers. However, numerous methodological and analytical shortcomings severely limit any interpretation of the German studies. We conclude that the more reliable epidemiologic data do not support a causal relationship between kidney cancer and TCE exposure.