When fast-twitch skeletal muscles of the adult rabbit are subjected to continuous low-frequency activity by electrical stimulation of the corresponding motor nerves, the fibers undergo an ultrastructural transformation, so that after 6 weeks they have acquired an appearance typical of slow-twitch fibers. In the present study, stimulation was discontinued at this stage in order to follow the reverse transformation, in which the fibers recovered their original morphological characteristics under conditions of normal endogenous activity. Stereological techniques were used to assess the time course of this process over a period of 20 weeks in terms of fiber cross-sectional area, extent of T-system, thickness of the Z-band, and volume fraction of mitochondria in the fiber core. Fibers of transformed muscles were smaller than those of control muscles, but the differences were no longer evident after 9 weeks of recovery. After 2 weeks the T-system was still of limited extent, as is characteristic of slow-twitch fibers; it increased toward the amount typical of fast-twitch fibers between 2 and 4 weeks, and had reached its full extent by 12 weeks. The wide Z-bands characteristic of slow-twitch fibers were retained for 4 weeks, but the thickness had begun to decrease by 8 weeks and recovery was complete by 12 weeks. The mitochondrial volume did not increase during recovery, in contrast to the large increases which had been observed to take place between 2 and 6 weeks during the fast-to-slow transformation. Overall, the recovery of fast-twitch ultrastructural characteristics was complete, but followed a more extended time course, and involved less myofibrillar disruption at an intermediate stage, than the original fast-to-slow transformation.

open hernia repair G3 or control G4 (surgical text on open hernia repair). The outcome measures were cognitive knowledge and overall global rating assessed by a checklist interview. Results: No differences in the baseline characteristics in trainees randomised to G1, G3 or G4 with mean similar ages, naivety for procedure and pre-intervention multiple-choice questionnaire. G1 trainees achieved significantly higher cognitive analysis performance scores for step-by-step knowledge of an open inguinal hernia mesh repair compared with trainees in G3 (p < 0.05) and G4 (p < 0.05). A similar significant finding was found for the general performance scores compared with trainees in G3 (p < 0.05) and G4 (p < 0.05). Conclusion: The interactive simulator of the open hernia facilitates clear thought processes and improves surgical trainees' knowledge of the hernia procedure step-by-step compared to other more traditional ways methods.

Implantable electronic stimulators were used to subject fast-twitch tibialis anterior and extensor digitorum longus muscles of adult rabbits to a chronically increased level of use. Stimulation was discontinued after 6 weeks and physiological, histochemical and biochemical properties of the muscles were examined at intervals over the ensuing 20 weeks. Previous work had shown that 6 weeks of stimulation was sufficient to bring about a substantial transformation of type in fast-twitch muscles, which then exhibited much of the character of muscles of the slow-twitch type. The present experiments showed that these stimulation-induced changes were completely reversible. The time-course of reversion was such that the muscles had recovered their original fast properties by about 12 weeks after the cessation of stimulation. The contractile characteristics and post-tetanic potentiation typical of fast muscle returned rapidly, in only 3-4 weeks, and over the same period the proportion of histochemical type 1 fibres declined from about 70% to control levels. Changes in fatigue-resistance, capillary density and enzyme activity followed a more prolonged time-course; in particular, the decline in the activity of enzymes of oxidative metabolism corre­sponded closely to that already established for the mitochondrial volume fraction. Reacquisition of fast properties was not accompanied by any changes in specific force-generating capacity. Observations from these experiments and from a related morphological study fit into a ‘first-in, last-out’ pattern for the response to stimulation and recovery. The slow-to-fast reversion that takes place during the recovery period provides a further opportunity for testing causal associations within the events underlying type transformation. It has important consequences for therapeutic applications that make use of the fatigue-resistant character of chronically stimulated muscle.

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Background: Haemoglobin disorders such as Sickle cell disease (SCD) have been acknowledged to be of great public health concern by the World Health Organization (WHO) in 2006. To reduce the tremendous public health and economic burden SCD exerts on many countries, the WHO is urging countries, especially those in Africa, to increase public awareness of the disease. Such awareness programmes among the young unmarried population will go a long way to prevent the birth of children with this painful genetic condition. Purpose: This study therefore sought to assess the level of knowledge, attitude to people living with SCD, and perception of SCD among undergraduate students of the University of Cape Coast, Ghana. Methods: A descriptive cross-sectional study was carried out. A total of 400 participants were selected using multistage sampling technique. Data was collected using a pretested, self-administered questionnaire and analyzed using SPSS software, version 25. Results: Almost all the students (96.75%) were aware of SCD. School and the media were the main sources of information (50.65%, 32.3% respectively). The mean knowledge score was 4.73 ± 2.41 (maximum score of 12) with 62%, 35.8% and 2.3% of participants having inadequate, moderate and adequate knowledge respectively. Majority of the participants (81.8%) had positive attitudes towards people living with SCD. Most respondents (78.5%) were likely to perform premarital genotype screening. Conclusion: In general, there was inadequate knowledge on SCD despite the high level of awareness among participants. Recommendation: Findings of the study highlights the need for continuous effective health education on sickle cell disease to students whose reproductive health choices will either increase or decrease the sickle cell disease burden in the very near future.