Coordinated ciliary beating requires Odf2-mediated polarization of basal bodies via basal feet

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Highlights? Mice expressing truncated Odf2 cough and sneeze due to primary ciliary dyskinesia ? Full-length Odf2 is needed for the formation of basal body-associated basal feet ? In the absence of basal feet, basal bodies fail to align with planar polarity cues ? Polarization of basal bodies by Odf2 is required for coordinated ciliary beating     

Effect of pre-treatment with St John's Wort on nephrotoxicity of cisplatin in rats

An herbal health care supplement, St John's Wort (SJW, Hypericum perforatum) has become widely used in the treatment of depression, and is known to interact with therapeutic drugs. Here we report a preventive effect of SJW on cisplatin nephrotoxicity in rats. Rats were given SJW (400 mg/kg/day, p.o.) for 10 consecutive days, and were injected with cisplatin (5 mg/kg, i.v.) on the day after the final SJW treatment. Cisplatin treatment increased the serum creatinine level, which is an index of nephrotoxicity, to 1.51+/-0.22 mg/dl (mean+/-SE) from 0.28+/-0.05 mg/dl (control) on day 5 after the cisplatin injection. This increase fell significantly to 0.86+/-0.13 mg/dl by pre-treatment with SJW. Cisplatin-induced histological abnormality of the kidney was blocked by pre-treatment with SJW. When SJW was administered for 10 days, the amounts of renal metallothionein (MT) and hepatic multidrug resistance protein 2 (Mrp2) were increased to 164.8+/-13.0% and 220.8+/-39.3% (mean+/-SE) of controls, respectively. GSH levels in the kidney and liver were not changed. Total and free cisplatin concentration in serum was not influenced by SJW treatment. In conclusion, the results suggest that pre-treatment with SJW may diminish cisplatin nephrotoxicity.     

Phylogeography of lethal male fighting in a social spider mite

When males fight for access to females, such conflict rarely escalates into lethal fight because the risks and costs involved, that is, severe injury or death, are too high. The social spider mite, Stigmaeopsis miscanthi, does exhibit lethal male fights, and this male–male aggressiveness varies among populations. To understand the evolution of lethal fighting, we investigated aggressiveness in 42 populations and phylogenetic relationships in 47 populations along the Japanese archipelago. By analysis of the male weapon morph, a proxy for aggressiveness, we confirmed the existence of a mildly aggressive (ML) form, besides the low aggression (LW) and high aggression (HG) forms reported earlier. To evaluate demographic history of these three forms, we employed the approximate Bayesian computation approach using mtCOI sequences and taking into consideration the postlast glacial expansion history of the host plant, Miscanthus sinensis. As results, hierarchical split models are more likely to explain the observed genetic pattern than admixture models, and the ML form in the subtropical region was considered the ancestral group. The inferred demographic history was consistent with the one reconstructed for the host plant in a previous study. The LW form was split from the ML form during the last glacial period (20,000–40,000 years BP), and subsequently, the HG form was split from the ML form at the end of or after the last glacial period (5,494–10,988 years BP). The results also suggest that the mite invaded Japan more than once, resulting in the present parapatric distribution of LW and HG forms in eastern Japan.     

The different effects of recombinant human tumor necrosis factor on rat fibrosarcoma sublines

Summary The antitumor effect of recombinant human tumor necrosis factor (rH-TNF) on two clones of rat fibrosarcoma with different metastatic potential to lymph nodes was examined. The colony formation of clone A, which has high metastatic potential, was completely inhibited by continuous exposure to rH-TNF at 50 U/ml. In contrast, colony formation of clone G, which has low metastatic potential, was not inhibited by high concentrations of rH-TNF (10,000 U/ml). The inhibitory effect of rH-TNF on colony formation by clone A was also observed with a 1-h exposure to rH-TNF. This effect was time and concentration dependent, as determined by the colony assay, ³H-thymidine uptake assay, and ⁵¹Cr-release assay. ³H-thymidine and ³H-uridine uptake per cell of clone A exposed to rH-TNF was not decreased. This suggests that the mechanisms of the antitumor effect of rH-TNF were not due to inhibition of DNA and RNA synthesis of tumor cells. In vivo growth and lymph node metastases of clone A inoculated i.p. to Donryu strain rats were completely suppressed by 14 consecutive i.p. injections of 10⁵ or 10⁶ U/kg per day of rH-TNF. On the other hand the growth of clone G was not influenced by rH-TNF administration.     

Gerres limbatus Cuvier and G. lucidus Cuvier from the Indo-Malay Archipelagos, the latter corresponding to young of the former (Perciformes: Gerreidae)

Taxonomic status of Gerres limbatus Cuvier in Cuvier and Valenciennes, 1830 and G. lucidus Cuvier in Cuvier and Valenciennes, 1830 was studied. The two species were reassessed as the same species, the latter corresponding to young of the former, on the basis of examination of their eight syntypes and other comparative specimens. Gerres limbatus clearly differs from other congeners in having 2½–3 (usually 2½) scales between the 5th dorsal fin spine base and the lateral line, and four or five diffuse, dark saddle patches mainly along the back in life (more apparent in small specimens less than ca. 65 mm in standard length, or preserved and stressed live specimens) (vs. usually more than 3½ scales between fifth dorsal fin spine base and lateral line, and and no such body color pattern of G. limbatus in other congeners). The species is currently known from the southern and western coasts of India including Sri Lanka, the Malay Peninsula, Gulf of Thailand, and Indonesia, becoming rare in occurrence eastward.     

The heterogeneity of human fibroblasts as determined from the effects of hydrocortisone on cell growth and specific dexamethasone binding

To elucidate the heterogeneity of human fibroblasts from lung and skin, the effects of hydrocortisone on cell proliferation and the specific dexamethasone binding to cells were studied. Hydrocortisone at physiological concentrations stimulated the proliferation in three strains of human fetal lung fibroblasts and inhibited it in two strains. There are two kinds of fibroblasts in the human fetal lung in addition to the human skin fibroblasts reported previously. Dexamethasone-binding experiments showed that human fibroblasts may be classified into two groups with respect to the dissociation constant (Kd) of the binding reaction. The heterogeneity of human fibroblasts shown by Kd could not be correlated to classification on the basis of the effects of hydrocortisone on cell proliferation. The differences in Kd for the binding reactions suggest differences in donor tissues from which human fibroblasts are derived.