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Purpose: The main tendon of the extensor hallucis longus (EHL) muscle attaches to the dorsal aspect of the distal phalanx of the great toe. One or multiple accessory tendons of the EHL have been reported in several ethnic/regional groups, except Taiwan. This study aimed to investigate the incidence, length, and insertion of the accessory tendon of the EHL in Taiwanese people. Methods: Anatomical dissection was performed on 48 feet of 24 formalin-embalmed cadavers. The occurrence and morphological characteristics of the accessory tendon of the EHL were recorded and analyzed. Results: The accessory tendon of the EHL was found in 97.92% (47/48) of the legs that were dissected. In one male cadaver, an independent muscle belly was identified in each leg, whereas all the other accessory tendons originated from the main tendon of the EHL. In this study, the insertion of the accessory tendon were classified into four patterns. The most common insertion sites were the first metatarsophalangeal (MTP) joint capsule and proximal phalanx of the great toe. The length of the accessory tendons did not correlate with age or with sex when the two tendons with independent muscle belly were excluded. Conclusions: The accessory tendon of the EHL appears to be a regular feature in Taiwanese people. Most accessory tendons of the EHL (85.7%) attached on the first MTP joint capsule may play a role in the prevention of capsular impingement during great toe extension. [ABSTRACT FROM AUTHOR]

Emergence of the intertidal midge, Pontomyia oceana Tokunaga, 1964, occurred semilunarly in southern Taiwan. The mean emergence time, or capture time, was concentrated within 1-2 h each evening, but varied by 4-6 h relative to sunset and low tide on different evenings. We used light treatments to investigate whether an endogenous clock was involved. Three light-dark (LD) cycles were necessary for entrainment of the population. Once entrained, the midges retained the rhythm, with a period of 24.5-25.0 h, for several days without LD cycles. These results support the clock hypothesis. Additional laboratory experiments indicated that a temperature change (±5°C) on the day of emergence altered the emergence time. Thus, the swarming time was controlled by both endogenous rhythms and temperature, but was not tightly linked to sunset. The resulting concentrated but variable emergence time makes midge swarming hard to anticipate and may lower their mortality rates from predation. [ABSTRACT FROM AUTHOR]

The article presents a study that deals with systematic status of Agehana elwesi f. cavaleriei swallowtail butterflies. The authors used morphology or molecular characters to examine the relationship between f. cavaleriei and A. maraho, an endangered taxon endemic to Taiwan. Based on the male genitalia and a 1530 bp fragment of mitochondrial DNA including the cytochrome oxidase I barcoding region, the authors linked f. cavaleriei with A. elwesi which is widespread in the southern part of continental China.

Gonadal hormones can modulate brain morphology and behavior. Recent studies have shown that hypogonadism could result in cortical function deficits. To this end, hormone therapy has been used to ease associated symptoms but the risk may outweigh the benefits. Here we explored whether genistein, a phytoestrogen, is effective in restoring the cognitive and central neuronal changes in late middle age and surgically estropause female rats. Both animal groups showed poorer spatial learning than young adults. The dendritic arbors and spines of the somatosensory cortical and CA1 hippocampal pyramidal neurons were revealed with intracellular dye injection and analyzed. The results showed that dendritic spines on these neurons were significantly decreased. Remarkably, genistein treatment rescued spatial learning deficits and restored the spine density on all neurons in the surgically estropause young females. In late middle age females, genistein was as effective as estradiol in restoring spines; however, the recovery was less thorough than on young OHE rats. Neither genistein nor estradiol rectified the shortened dendritic arbors of the aging cortical pyramidal neurons suggesting that dendritic arbors and spines are differently modulated. Thus, genistein could work at central level to restore excitatory connectivity and appears to be potent alternative to estradiol for easing aging and menopausal syndromes.