The role of calcitonin gene-related peptide in migraine prevention by botulinum toxin type A

@#Objectives: Calcitonin gene-related peptide (CGRP) is currently considered to be a major contributing factor in migraine headache. Botulinum toxin type A (BTXA) was found to be effective in migraine prevention. However, the mechanism of action in patients was unknown. Using injection as in clinical setting, the study aimed to determine whether BTXA could decrease the sensitization of the trigeminovascular nociceptive system through the reduction of CGRP action. Methods: Adult male Wistar rats were pretreated with normal saline solution or BTXA before KCl application to induce cortical spreading depression (CSD) or NaCl application as a control. Regional cerebral blood flow at parietal cortex was measured for 90 min after KCl or NaCl application. Tissues from trigeminal ganglion (TG) and trigeminal nucleus caudalis (TNC) were then collected for CGRP and c-Fos measurement respectively. Results: BTXA pretreatment significantly decreased the cumulative blood flow and number of hyperemic peaks induced by KCl. Numbers of CGRP positive cells at TG and c-Fos positive cells at TNC were also reduced by BTXA.Conclusion: BTXA pretreatment reduced CGRP production and release from the TG leading to lessen CSD production and persistent activation of TNC which played a major role in migraine headache.

Incidence and morphometry of bony projections on the cerebral aspect of the petromastoid part of temporal bone in adult human skulls

To find out the incidence, side, position and morphometry of bony projections on the cerebral aspect of the petromastoid part of the temporal bone of dry adult human Bangladeshi skulls. It is an observational study. The incidence, side and position of the bony projections on the cerebral aspect of petromastoid part of temporal bone was ascertained by observation. The size of the bony projection was measured by millimeter scale. Department of Anatomy, Rajshahi Medical College, Rajshahi, Bangladesh. Out of total 100 petromastoid part of temporal bone [50 human skulls] bony projection was present in 44 [44%] close to the upper part of the groove for the sigmoid sulcus. The bony projection was unilateral and bilateral in 12 [27.3%] and 32 [72.7%] cases respectively and the incidence was equal [50%] on both right and left side. The projections were small, medium and large size in 26 [59.1%], 15 [34.1%] and 3 [6.8%] cases respectively. Position of the superior petrosal sulcus was superior and inferior to the bony Projection in 34 [77.3%] and 6 [13.6%] cases. In 4 [9.1%] the sulcus was inconspicuous. For an extensive exposure of clivus and petrous regions and their associated neural and vascular structures the tentorium cerebelli has to be dissected. The bony projection is closely related to the attachment of tentorium cerebelli and to the superior petrosal and sigmoid sinus. Thus awareness about its incidence and nature is important for the neurosurgeon and neurootologist to avoid any neurological and vascular accident

Occipital emissary foramen in Bangladeshi skulls

To ascertain the incidence and position of the emissary vein in the squamous part of the occipital bone from the posterior margin of the foramen magnum to occipital protuberance. Design: It is an observational study to evaluate the incidence of emissary vein in the squamous part of the occipital bone in Bangladeshi skulls. Setting: Department of Anatomy, Rajshahi Medical College; Bangabandhu Sheikh Mujib Medical University [BSMMU], Dhaka; Bangladesh College of Physician and Surgeon, Dhaka; Shahid Ziaur Rahman Medical College, Bogra; Khulna Medical College; North Bengal Medical College, Sirajgang, Bangladesh. Out of total 150 dry human adult skulls occipital emissary foramen was present in 21 [14%] skulls. Left and right-sided foramen were 7 [4.66%] and 10 [6.66%] respectively but the median foramen was 4 [2.66%]. The incidence and positions of the occipital emissary veins are important for the neurosurgeons during their such occipital surgery as these will given them awareness to avoid the excessive bleeding

Variation in shape of the lingulae in the adult human mandible of Bangladeshi skulls

To ascertain the prevalence and forms of presentation of lingula in adult human mandible. Design: It is an observational study to evaluate the incidence and forms of presentation of lingulae in adult human mandible in Bangladeshi skulls. Setting: Department of Anatomy, Rajshahi Medical College; College of Physician and Surgeon, Dhaka; North Bengal Medical College Sirajganj, Bangladesh. The lingula of both sides of total 208 dry human mandibles are 171 males and 37 females. Depending on shape they were 3 types: 1- triangular 292 [70.2%]; 2- truncated 84[20.2%]; 3-assimilated 40 [9.6%]. Bilaterally lingula were found triangular in 139, truncated in 37 and assimilated in 18 mandibles. Of the remaining 14 mandibles with different appearances on the two sides. Triangular had on left [11] and right [3] sides, truncated on left [2] and right [8] sides respectively. It is noted that, unilateral presentation of truncated type solely confined in male. But in assimilated type left [1] and right [3] sides. The incidence of different types were more common in male than female. As a whole the assimilated type is least common in female. The incidence and forms of presentation of lingula could be used as anthropological markers to assess different populations and races. Because of intimate relationship to the inferior alveolar nerve, it is clinically significant for the orodental surgeon