2D:4D ratios predict hand grip strength (but not hand grip endurance) in men (but not in women)

In humans, the ratio of the second digit to the fourth digit — the 2D:4D ratio — is a sexually dimorphic trait (men, on average, exhibit lower 2D:4D ratios than do women) that is influenced by prenatal testosterone exposure, but not by circulating testosterone levels in adulthood. Consequently, 2D:4D ratios are commonly used as indirect measures of prenatal testosterone exposure. Many studies have examined the associations of 2D:4D ratios with sexually dimorphic adaptations that are thought to be influenced by such exposure, including physical prowess. The existing literature, however, remains unclear as to (1) whether 2D:4D ratios are more closely linked to strength or to endurance; and (2) whether 2D:4D ratios are linked with physical prowess for both men and women. In 100 men and 122 women, the relationship of 2D:4D ratios with maximum voluntary contraction (MVC) scores (hand grip strength) and maximum endurance time (MET) scores (local muscular endurance) using a hand dynamometer was examined. Controlling for age, height, weight, and average digit length, we found that 2D:4D ratios significantly predicted MVC scores in men, but not in women. 2D:4D ratios did not significantly predict MET scores for either sex. These results suggest that prenatal testosterone exposure in this sample is significantly related to hand grip strength in men, but not in women (and to local muscular endurance in neither sex), and, therefore, that strength, rather than local muscular endurance, potentially drives the relationship between 2D:4D ratios and physical prowess.     

Bacteriophage T4-Directed DNA Synthesis in Toluene-Treated Cells

DNA synthesis has been studied in T4-infected Escherichia coli cells made permeable to nucleotides by treatment with toluene. The rate of incorporation of labeled deoxyribonucleoside triphosphates into DNA at various times after infection is proportional to the in vivo rate. This in vitro incorporation is dependent on all four deoxyribonucleoside triphosphates (5-hydroxymethyldeoxy-cytidine triphosphate can substitute for dCTP) and Mg(2+). It is stimulated by rATP, partially inhibited by pancreatic DNase, and abolished by N-ethylmalei-mide and 1-beta-d-arabinofuranosylcytosine triphosphate. T4 amber DO (DNA negative) and temperature-sensitive DO mutants under nonpermissive conditions of infection fail to induce DNA synthesis in vitro. The synthesizing activity is intracellular and the DNA product is exclusively T4 DNA. The in vitro synthesis proceeds in a discontinuous manner involving synthesis and subsequent joining of small DNA fragments (about 10S in alkaline sucrose gradients) into larger molecules predominantly one-half the length of mature T4 DNA. No restriction of C-containing or nonglucosylated HMC-containing T4 DNA product is observed in this system.     

The isolation of potato virus S from the leaves of potato plants using precipitation by polyethylene glycol

A purified potato virus S was prepared using precipitation by the solution of 35% polyethylene glycol 4000 in the presence of an electrolyte. The mixture for precipitation of the potato virus S had to contain 11% polyethylene glycol and 0·25m NaCl. The S virus was extracted by 0·01m phosphate buffer, pH 7·5, from the precipitation separated by centrifugation. One part of the extract was further purified by means of differential centrifugation and the other by means of gel filtration on Sephadex G-100. The ultraviolet absorption measurements of both preparations showed that the differential centrifugation gave a purer preparation than the gel filtration.     

Research on substances inactivating the X virus present in sap from potato leaves

The work ofJermoljev andBr?ák (1964) showed that the sap of potato leaves contains substances inactivating X, Y and S viruses and that there was an increasing trend in the content of these substances in varieties resistant to these viruses. In further research it was found that potato tubers of varieties which are resistant and susceptible to the viruses contained the same amounts of inactivating substances. Differences in the power of inactivating the viruses evidently appeared in the leaves. Inactivating substances could be removed by boiling, they did not pass through a dialysing membrane and were adsorbed by animal charcoal. On centrifuging sap from potato leaves in a Spinco L ultracentrifuge for 60 min. at 40,000 r.p.m., the inactivating substances remained in the supernatant. When sucrose gradient centrifugation for 60 min. at 24,000 r.p.m. was employed, the inactivating substances remained in the layer of sap and 10% sucrose. Inhibition of the activity of certain enzyme groups did not affect the power of sap to inactivate X virus. Inactivating substances could be isolated chemically. The best method of isolation, however, was fractionation of sap, after ultracentrifugation, on a Sephadex G 50 column, rinsing the column with McIlvaine buffer at pH 6·5. Inactivating substances can be isolated, concentrated and preserved by lyophilization by this method. It is difficult to say precisely to what chemical group the inactivating substances belong. Some reactions indicate that they may be low molecular proteins.     

Comparative studies between in vitro and in vivo effects of human beta-interferon on natural killer activity and its relevance to immunochemotherapy

Summary A good correlation was found between in vivo and in vitro responses of peripheral MNC from breast cancer patients and the NK boosting effect of human IFN. In vitro immunochemotherapy studies showed that marked antitumor effects were obtained against cultured cancer cells when a widely used chemotherapeutic agent such as 5-FU was combined with nonsensitized spontaneously cytolytic MNC, preactivated in vitro with IFN. These results suggest that the in vitro susceptibility assay of MNC to IFNs could be used for predicting favorable responses to immunochemotherapy regimens employing IFNs as immunomodulating agents. Abbreviations used: IFN, beta-interferon; CM, complete medium; CTX, cyclophosphamide; E:T ratio, effector target ratio; EDTA, ethylenediaminetetraacetic acid; FCS, fetal calf serum; 5-FU, 5-fluorouracil; IFN, gamma-interferon; Hepes, N-2-hydroxyethylpiperazine-N-2-ethanesulphonic acid IFNs, interferons; KC, killed cells; LDIF, low doses beta-interferon; LU, lytic unit; MAT macrotest; MIT, microtest; MNC, mononuclear cells; MNC/IFN, IFN-pretreated MNC; MTX, methotrexate; NB, no boosting; NK, natural killer; NKA, NK activity; NR, natural resistance; PM, positive modulation; SE, standard error; WM, washing medium     

No evidence of modulation of indirect plant resistance of Brassica rapa plants by volatiles from soil-borne fungi

1. Upon herbivory, plants emit specific herbivore-induced plant volatiles (HIPVs) that can attract natural enemies of the herbivore thus serving as indirect plant resistance. Not only insect herbivores, but microorganisms may also affect HIPV emission before or after plant colonisation, which in turn can affect behaviour of natural enemies of the herbivore. Yet, it remains elusive whether volatiles from microorganisms influence HIPV emission and indirect plant resistance.
2. In this study, we investigated whether exposure of Brassica rapa roots to volatiles from soil-borne fungi influence HIPV emission and the recruitment of natural enemies of Pieris brassicae larvae.
3. Using a two-compartment pot system, we performed greenhouse and common-garden experiments, and we profiled plant HIPV emission.
4. We found that exposure of plant roots to fungal volatiles did not affect the number of P. brassicae larvae recollected from the plants, suggesting a neutral effect of the fungal volatiles on natural predation. Likewise, in a greenhouse, similar numbers of larvae were parasitised by Cotesia glomerata wasps on control plants as on fungal volatile-exposed plants. Additionally, chemical analysis of HIPV profiles revealed no qualitative and quantitative differences between control plants and fungal volatile-exposed plants that were both infested with P. brassicae larvae.
5. Together, our data indicate that root exposure to fungal volatiles did not affect indirect plant resistance to an insect herbivore. These findings provide new insight into the influence of indirect plant resistance by fungal volatiles that are discussed together with the effects of fungal volatiles on direct plant resistance.

     

Creatine nanoliposome reverts the HPA-induced damage in complex II–III activity of the rats’ cerebral cortex

Molecular Biology Reports - Phenylketonuria (PKU) is a metabolic disorder accumulating phenylalanine (Phe) and its metabolites in plasma and tissues of the patients. Regardless of the mechanisms,...     

The conversion of procyanidins and prodelphinidins to cyanidin and delphinidin

The hydrolysis of proanthocyanidins to anthocyanidins in n-BuOH-HCl (95:5) has been shown to be an autoxidation, the yield of anthocyanidin being critically dependent on trace metal-ion impurities. Reproducible yields of anthocyanidin may be achieved if iron (III) salts are added to the reaction medium, and a standard method of analysis of proanthocyanidins based on use of an n-BuOH-HCl-Fe^III mixture is given. The ratio of absorbance maxima of the cyanidin (550 nm) produced to that near 280 nm for the original procyanidin polymer solution was ～ 3.5.     

Risk factors for tungiasis in Nigeria: identification of targets for effective intervention

Background

The parasitic skin disease tungiasis (caused by the flea Tunga penetrans) affects resource-poor communities in Latin America, the Caribbean and sub-Saharan Africa. Prevalences in endemic areas are high, and severe pathology occurs commonly. However, risk factors for infestation have never been assessed in Africa.

Methods and Findings

A cross-sectional study was conducted in Erekiti, a rural community in Lagos State (Nigeria), where tungiasis is endemic. Individuals were examined clinically for the presence of tungiasis, and a questionnaire was applied. Data from 643 individuals (86.6% of the target population) were analyzed; 252 (42.5%) were infested with T. penetrans. In the multivariate logistic regression analysis, presence of pigs on the compounds (adjusted odds ratio = 17.98; 95% confidence interval: 5.55–58.23), sand or clay floor inside houses (9.33; 5.06–17.19), and having the common resting place outside the house (7.14; 4.0–14.29) were the most important risk factors identified. The regular use of closed footwear (0.34; 0.18–0.62) and the use of insecticides indoors (0.2; 0.05–0.83) were protective against infestation. The population attributable fractions associated with tungiasis were: sand or clay floor inside the house (73.7%), resting usually outside the house (65.5%), no regular use of closed footwear (51.1%), and pigs on the compound (37.9%).

Conclusion

The presence of tungiasis in Erekiti is determined to an important extent by a limited number of modifiable variables. Effective and sustainable intervention measures addressing these factors need to be implemented in this and other West African communities with high disease burden.