A case-control study of the association between socio-demographic, lifestyle and medical history factors and multiple sclerosis

OBJECTIVE: The etiology of multiple sclerosis (MS) remains poorly understood. Socio-demographic characteristics may play important roles in its development. METHODS: In a case-control study of MS, a total of 200 newly diagnosed MS patients and 202 frequency age- and sex-matched controls were studied. RESULTS: A direct and significant association was observed between cigarette smoking and the risk of MS. Higher education seemed to reduce the risk of MS. Contact with cats was inversely associated with MS, particularly in males, whereas contact with caged birds increased the risk significantly, especially in females. A strong family aggregation of MS was observed among cases. A past history of trauma and eye problems appeared to pose a high risk of MS. Cases had a significant family history of eye problems, mumps, measles, rubella, cancer and auto-immune diseases. CONCLUSION: If smoking and history of certain infectious diseases increase the risk of MS significantly, they could be modified and avoided, thereby reducing the likelihood of being afflicted by MS.     

Apoptosis in the basal ganglia of the developing human nervous system

Programmed cell death (PCD) plays a crucial role in the development of the central nervous system through controlling neuronal numbers and adequate synaptic connections. PCD has been considered to occur in the form of apoptosis. To examine how apoptosis occurs in the developing human brain, we performed a morphometric TUNEL study, using a commercially available kit (ApopTag Kit, Oncor Inc.). We examined apoptotic cells in the basal ganglia of 47 fetuses and newborns without macroscopical and microscopical evident congenital anomalies. Gestational age ranged from 12 to 40 weeks. The numerical density as well as the labeling index of TUNEL-positively labeled nuclei were evaluated. In the caudate nucleus and putamen, TUNEL-labeled cells were observed around the 12th week of gestation. The numerical density of total cells was significantly decreased, whereas the labeling index of apoptotic cells was significantly increased with advanced gestational age. In the globus pallidus, the numerical density of total cells decreased with advancing gestational age, while the labeling index of apoptotic cells increased between the 20th and 28th week, followed by a decrease until the 40th week. The analysis of TUNEL-positive cells revealed a different reaction pattern for the various basal ganglia with regard to the timing and degree of the apoptotic process in regulating cell numbers.     

Nutritional factors and pancreatic cancer in the francophone community in Montréal, Canada.

In a population-based case-control study of dietary risk factors for pancreatic cancer, a total of 179 cases and 239 controls were interviewed between 1984 and 1988. This study demonstrated an increased risk of pancreas cancer associated with high levels of reported energy intake. After adjustment for age, sex, response status, lifetime cigarette consumption and energy intake, there appeared to be an association with total fat intake (odds ratio in highest quartile relative to lowest quartile 2.24 [95% Confidence Interval (0.74, 6.73)] and, particularly, saturated fat [OR = 4.32, 95% CI(1.39,13.7)]. Although dietary cholesterol intake appeared to increase risk and a number of many micro-nutrients were apparently associated with reductions of risk, none were statistically significant. The results are consistent with a role of nutritional factors in the etiology of pancreatic cancer. The magnitude of the risks involved emphasizes the necessity for larger studies of this topic.     

The link between exocrine pancreatic cancer and the endocrine pancreas

Summary Background. The histogenesis of pancreatic cancer is still debatable. Ductal, ductular, and acinar cells all have been declared the tumor progenitor cells. Our long-term human and experimental studies indicate that pancreatic ductal adenocarcinomas arise within ductal cells and islets. Supporting studies are presented in this article. Methods. Several human studies and experimental studies on Syrian hamsters conducted within the last 20 years were used in this article. Hamster and human islets were established, and their growth and morphologic changes were examined electron microscopically, immunohistochemically, cytogenetically, and molecular biologically. Results. Studies using the hamster pancreatic cancer model showed that most pancreatic adenocarcinomas develop within islets, most probably from stem cells, which are also believed to be the progenitor cells for tumors that develop within ducts. Studies in newly established human and hamster islets culture validated the immense potential of islet cells to differentiate and become malignant. The higher susceptibility of islet cells to become malignant could be related to their high drug-metabolizing enzymes and their high proliferation rate. Dietary studies indicate that the promoting effect of a high-fat diet on pancreatic carcinogenesis is unrelated to the energy intake, but rather is related to its effect on islet cell replication. Conclusion. Experimental and human studies during 20 years of research in our laboratories point to the importance of pancreatic islets in the development of ductal-type adenocarcinomas. We believe that pancreatic cancer that develops within ducts, but more frequently within islets, derives from pancreatic stem cells that are distributed within the ductal trees and within the islets The data was presented at the 8th meeting of the International Association of Pancreatology, as the IAP Founder’s Lecture July 14, 1998 in Tokyo, Japan.