Motor neurons that control limb movements are organized as a neuronal nucleus in the developing ventral horn of the spinal cord called the lateral motor column. Neuronal migration segregates motor neurons into distinct lateral and medial divisions within the lateral motor column that project axons to dorsal or ventral limb targets, respectively. This migratory phase is followed by an aggregation phase whereby motor neurons within a division that project to the same muscle cluster together. These later phases of motor neuron organization depend on limb-regulated differential cadherin expression within motor neurons. Initially, all motor neurons display the same cadherin expression profile, which coincides with the migratory phase of motor neuron segregation. Here, we show that this early, pan-motor neuron cadherin function drives the divisional segregation of spinal motor neurons in the chicken embryo by controlling motor neuron migration. We manipulated pan-motor neuron cadherin function through dissociation of cadherin binding to their intracellular partners. We found that of the major intracellular transducers of cadherin signaling, ␥-catenin and ␣-catenin predominate in the lateral motor column. In vivo manipulations that uncouple cadherin-catenin binding disrupt divisional segregation via deficits in motor neuron migration. Additionally, reduction of the expression of cadherin-7, a cadherin predominantly expressed in motor neurons only during their migration, also perturbs divisional segregation. Our results show that ␥-catenin-dependent cadherin function is required for spinal motor neuron migration and divisional segregation and suggest a prolonged role for cadherin expression in all phases of motor neuron organization.

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A seroprevalence study was carried out on serum samples obtained from blood of cattle slaughtered at Sokoto metropolitan abattoir, Sokoto, Nigeria. Systematic random sampling was used to select the animals. Serum samples of 372 cattle of different sexes and breeds were analyzed using ID Screen ® BVD p80 Antibody Competition ELISA Test kit for the presence of bovine viral diarrhea antibodies. Two hundred and forty seven (247), representing 66.39% of the samples, were found positive for the antibodies against bovine viral diarrhea virus (BVDV). More female animals appeared to have BVDV antibodies than the males (p<0.05). Sokoto Gudali breed of cattle recorded the highest number of positive cases of BVDV (p>0.05). The result of this research suggests that there is an existence of BVDV within the study area and that the spread of the BVDV antibodies seems to cut across sex and breed of cattle within the state. It is suggested that virological research on BVDV should be carried out in the state.

Appreciating basic neuro‐anatomy by medical students plays a vital role in their understanding of the pool of neurological diseases and illnesses found in Nigeria and sub‐Saharan Africa. This study was conducted to ascertain the perception of Nigerian medical students about neuro‐anatomy in comparison with other aspects of human anatomy course. The study participants are third year students from 2 medical schools in Northwestern Nigeria. Anonymous and voluntary questionnaire was distributed to the randomly selected participants. To date, out of the 120 questionnaires distributed, a total of 116 have been completed and returned. Information obtained has been entered into Microsoft Excel Worksheet after which relevant descriptive and inferential statistics will be applied. Preliminary findings from the completed and returned questionnaires, revealed that majority of the medical students perceived neuro‐anatomy course as the most difficult aspect of human anatomy. So far, 60% of the respondents consider poor teaching methodology employed by the neuro‐anatomy tutors as the main reason for their negative perception and suggested the use of models as well as teaching aids to enhance learning. This study would probably give a hint as to why most medical graduates never considered picking up careers in neurology or neuroscience related fields, thus making it difficult to address the health challenges noticed in these fields of endeavors.