Israel Medical Association Journal

Background: Most corneal damage induced by contact lenses is due to interference with corneal oxygenation.

Objective: To investigate the effect on the rabbit cornea of a rigid gas-permeable contact lens with a newly designed periphery.

Method: We fitted New Zealand white rabbits (n=12) with RGP[1] contact lenses that were identical in all respects except for the design of the periphery. In each animal, one contact lens had an innovative periphery consisting of a microscopic diffractive relief lathed on the back surface; the other contact lens was of a conventional design. The lenses were worn continuously for 7 days. During this experimental period and for 1 additional week we assessed the corneal damage by daily testing lactic dehydrogenase activity in the tears.

Results: On the last day of the experimental week and the first 3 days of the healing period, mean tear LDH[2] activity was significantly lower in the eyes with the new contact lens design than in eyes with the conventional lenses.

Conclusions: The novel periphery design reduces corneal damage resulting from contact lens wear, as reflected by LDH levels in the tears. The new design probably facilitates the flow and exchange of tears under the contact lens, resulting in improved metabolism of the cornea. These findings may also prove applicable to soft contact lenses.

Background: First-degree relatives of colorectal cancer patients are the largest groups of individuals at increased risk for colorectal cancer.

Objective: To assess the knowledge, attitudes and behavior to disease prevention and colorectal cancer screening among first-degree relatives of colon cancer patients.

Methods: A descriptive, point-prevalence epidemiological study was conducted among 215 first-degree relatives of survivors of colorectal cancer in the southern (Negev) region of Israel. Variables included perceived health status, knowledge about cancer screening, compliance rates with colorectal cancer screening, and interest in participation in early detection programs in the future.

Results: The mean age of the respondents was 47.9111.2 years, and 54% were males. Only 58 (27%) remembered having been encouraged to undergo an early detection test. In the previous year only 15% underwent fecal occult blood tests, while 9% had a barium enema and 14% an endoscopic examination of the colon by sigmoidoscopy or colonoscopy. A total of 49% of the asymptomatic respondents were unaware of recommendations for screening, and only 38.3% expressed any interest in participating in early detection programs in the future. Only 19% of respondents over the age of 50 and 8% of respondents over age 60 were interested in participating compared with 49% under the age of 50 (P0.0001).

Conclusion: A minority of first-degree relatives of colorectal cancer patients reported having been counseled to undergo screening, although most had seen their family physician in the previous 3 years. Primary care physicians should be more active in informing at-risk patients and encouraging them to undergo periodic screening.

Background: Familial dysautonomia is a genetic disease in which there is a defect in the autonomic and sensory nervous systems. These systems have a major role in the reproductive system.

Objective: To study the inter-relationship of autonomic and sensory dysfunction and gynecological function.

Methods: The gynecological histories of 48 women with familial dysautonomia were analyzed retrospectively. Their mean age was 22.25 years (range 12-47). Thirty-three women (65%) were available for further questioning and investigation of hormonal status.

Results: Menarche had occurred in 32 of the 48 (66.7%). Their average age of menarche was significantly delayed as compared to their unaffected mothers (15.5 vs. 13.6 years respectively, P=0.002). The most prominent finding was the very high prevalence, 81.2%, of premenstrual symptoms. Seven of 26 had premenstrual syndrome symptoms of dysautonomic crisis. Blood sex hormone levels were normal in 27 of the 33 patients studied. None reached natural menopause. One patient had adenomyosis, and another, dysgerminoma. Three patients became pregnant and delivered healthy infants.

Conclusion: Menarche is delayed in women with FD, and the physiological monthly hormonal fluctuations may disturb autonomic homeostasis sufficiently to precipitate dysautonomic crisis.

There is increasing evidence to suggest that aspirin and other non-steroidal anti-inflammatory drugs reduce the risk of colorectal cancer. This observation is supported by animal studies that show fewer tumors per animal and fewer animals with tumors after administration of several different NSAIDs. Intervention data in familial adenomatous polyposis have established that the effect is exerted on the process of human colonic adenoma formation. Supportive evidence in sporadic colorectal neoplasia, derived from 22 of 24 studies (both case-control and cohort), found a reduced risk in men and women for cancers of the colon and the rectum and for both aspirin and the other NSAIDs. Earlier detection of lesions as a result of drug-induced bleeding does not seem to account for these findings. Although the molecular mechanism responsible for the chemopreventive action of this class of drugs is not yet completely understood, the protection may affect several pathways including both cell cycle arrest and induction of apoptosis.

In the third millennium the question is not if but how. Based on the consistency of epidemiological, clinical and experimental data, the association between regular long-term aspirin or NSAIDs intake and a decreased death rate from colorectal cancer is sound and there is no need for further placebo trials. At the same time, despite this consistency there is no clear data on the dose, duration or frequency of use for cancer-preventive activity.