Possible influence of styloid process length on isolated vertigo of unknown aetiology.

OBJECTIVE: Eagle syndrome or styloid process syndrome is a clinical condition of complex aetiology. Since, as a consequence of vascular compression,due to the length of the styloid process and its nearness to the internal carotid artery,it can lead to vertigo. Vertigo may be the only symptom of stylocarotid syndrome and it is extremely challenging diagnose.To the best of our knowledge, this is the first study that measures the lengths of styloid process on the Croatian population's,and possible influence of styloid process length on isolated vertigo of unknown aetiology. METHODS: This study included 829 subjects who were divided into two groups.The first group was the control group, consisting of 800 subjects.The second group, study group, consisted of 29 subjects who suffered from the vertigo of unknown aetiology. RESULTS: The statistically significant difference between the study and the control group was observed in the length of the styloid process, and in the closest distance of the styloid process from the carotid artery. CONCLUSIONS: The prolonged styloid process and its close association with the internal carotid artery may affect vertigo of unknown aetiology and should be clinically and radiographically investigated in cases of unexplained vertigo as an isolated and only symptom within stylocarotid syndrome.

Palindrome content of the yeast Saccharomyces cerevisiae genome.

Palindromic sequences are important DNA motifs involved in the regulation of different cellular processes, but are also a potential source of genetic instability. In order to initiate a systematic study of palindromes at the whole genome level, we developed a computer program that can identify, locate and count palindromes in a given sequence in a strictly defined way. All palindromes, defined as identical inverted repeats without spacer DNA, can be analyzed and sorted according to their size, frequency, GC content or alphabetically. This program was then used to prepare a catalog of all palindromes present in the chromosomal DNA of the yeast Saccharomyces cerevisiae. For each palindrome size, the observed palindrome counts were significantly different from those in the randomly generated equivalents of the yeast genome. However, while the short palindromes (2-12 bp) were under-represented, the palindromes longer than 12 bp were over-represented, AT-rich and preferentially located in the intergenic regions. The 44-bp palindrome found between the genes CDC53 and LYS21 on chromosome IV was the longest palindrome identified and contained only two C-G base pairs. Avoidance of coding regions was also observed for palindromes of 4-12 bp, but was less pronounced. Dinucleotide analysis indicated a strong bias against palindromic dinucleotides that could explain the observed short palindrome avoidance. We discuss some possible mechanisms that may influence the evolutionary dynamics of palindromic sequences in the yeast genome.