Effect of psoralen-induced photodermatitis on tryptophan metabolism in rats

Tryptophan metabolism ‘via kynurenine’ has been studied in rats before and after induction of experimental light-conditioned dermatitis with psoralen. Tryptophan load in animals during the acute phase of dermatitis (one day after induction) causes a markedly increased urinary excretion of total metabolites in comparison with that obtained before dermatitis. During this phase of the skin disease tryptophan pyrrolase activity is significantly increased and kynureninase activity significantly decreased in liver in respect to the control animals. Kynurenine aminotransferase activity shows no significant variations in both liver and kidneys. After 6 days of dermatitis, when the skin damage is in repair, both the excretory values of the urinary metabolites after L-tryptophan load and the enzymic activities are similar to those before dermatitis.     

Gonadotropin, prolactin and thyrotropin pituitary secretion after exogenous dehydroepiandrosterone-sulfate administration in normal women.

The effect of exogenous dehydroepiandrosterone-sulfate (DHAS) on luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin (PRL) and thyroid-stimulating hormone (TSH) pituitary secretion was studied in 8 normal women during the early follicular phase. The plasma levels of these hormones were evaluated after gonadotropin-releasing hormone (GnRH)/thyrotropin-releasing hormone (TRH) stimulation performed after placebo or after 30 mg DHAS i.v. administration. The half-life of DHAS was also calculated on two subjects; two main components of decay were detected with half-times of 0.73-1.08 and 23.1-28.8 h. The results show an adequate response of all hormones to GnRH or TRH tests which was not significantly modified, in the case of LH, FSH and PRL, when performed in the presence of high levels of DHAS. However, the TSH response to TRH was significantly less suppressed (p less than 0.05) (39%) after DHAS administration than during repeated TRH stimulation without DHAS (51%). The data support the hypothesis that DHAS does not affect LH, FSH and PRL secretion, while TSH seemed to be partially influenced.     

DNA synthesis in vivo and in vitro in Escherichia coli irradiated with ultraviolet light

DNA synthesis was followed in vivo and in permeable Escherichia coli after ultraviolet light irradiation, irradiation and incubation in a growth medium containing chloramphenicol and in unirradiated cells. In vitro, replicative type DNA synthesis was partially restored after incubation of cells in medium containing chloramphenicol, but not in vivo. The DNA was pulse-labeled in permeable cells in the presence of deoxyribonucleoside triphosphates and ribonucleoside triphosphates. dCTP was replaced by 5-Hg-dCTP as a substrate for DNA synthesis. Hg-DNA was separated from cellular nucleic acids on thiol-agarose affinity columns. The 5' termini of newly synthesized DNA were analyzed after treatment with alkaline phosphatase and rephosphorylation with polynucleotide kinase and [gamma-32P]ATP. DNA synthesis in unirradiated permeable E. coli represents a replicative process dependent on ATP and inhibited by novobiocin. About 70% of the nascent DNA carried terminally labeled RNA moiety at its 5' end. In vitro DNA synthesis in irradiated cells was suppressed and hardly influenced by the presence of ATP or novobiocin. The 5'-RNA content of this cell population was less than 5%.     

Morphological divergence in giant fossil dormice

Insular gigantism—evolutionary increases in body size from small-bodied mainland ancestors—is a conceptually significant, but poorly studied, evolutionary phenomenon. Gigantism is widespread on Mediterranean islands, particularly among fossil and extant dormice. These include an extant giant population of Eliomys quercinus on Formentera, the giant Balearic genus †Hypnomys and the exceptionally large †Leithia melitensis of Pleistocene Sicily. We quantified patterns of cranial and mandibular shape and their relationships to head size (allometry) among mainland and insular dormouse populations, asking to what extent the morphology of island giants is explained by allometry. We find that gigantism in dormice is not simply an extrapolation of the allometric trajectory of their mainland relatives. Instead, a large portion of their distinctive cranial and mandibular morphology resulted from the population- or species-specific evolutionary shape changes. Our findings suggest that body size increases in insular giant dormice were accompanied by the evolutionary divergence of feeding adaptations. This complements other evidence of ecological divergence in these taxa, which span predominantly faunivorous to herbivorous diets. Our findings suggest that insular gigantism involves context-dependent phenotypic modifications, underscoring the highly distinctive nature of island faunas.     

Potentially handicapped but otherwise functional: Malformations in prey capture tools show no impacts on octopus life

Larval mortality is a keystone ecological factor for many benthic octopus since it mostly occurs before their settlement in the sea bottom as benthic juveniles. The literature had revealed that records of adult animals with morphological abnormalities (teratologies) are fewer in species with complex life cycle than in those with direct development. This is a direct consequence of the morphological, physiological, and development challenges that the transition from the larval to the adult morphology represents. During a routine fishing sample, we found an immature female horned octopus with additional buccal structures in two suckers of its ventral arms, likely rendering these suckers as inefficient. Based on the literature about the natural history of octopus, we provide evidence that these abnormalities were present at the moment of hatch. We evaluated the impact of the teratologies by comparing the shape of the buccal beaks and the trophic niche of the individual with five normal conspecifics. Although the beaks showed a different shape than normal individuals, the trophic niche was similar. Surprisingly, the teratological condition of the individual likely had no severe impacts on its life, even though it likely represents a handicap for its survival during its planktonic life. We also comment on other previous records from the literature of teratological adult octopus to highlight the amazing adaptive capacity of octopus to deal with challenging morphologies.     

Plant–Environment Interactions in the Low Arctic Torngat Mountains of Labrador

Ecosystems - The eastern Canadian Subarctic and Arctic are experiencing significant environmental change with widespread implications for the people, plants, and animals living there. In this...     

Hepatocellular cancer therapy in patients with HIV infection: Disparities in cancer care,trials enrolment,and cancer-related research

In the highly active antiretroviral therapy (HAART) era, hepatocellular carcinoma (HCC) is arising as a common late complication of human immunodeficiency virus (HIV) infection, with a great impact on morbidity and mortality. Though HIV infection alone may not be sufficient to promote hepatocarcinogenesis, the complex interaction of HIV with hepatitis is a main aspect influencing HCC morbidity and mortality.Data about sorafenib effectiveness and safety in HIV-infected patients are limited, particularly for patients who are on HAART. However, in properly selected subgroups, outcomes may be comparable to those of HIV-uninfected patients. Scarce data are available for those other systemic treatments, either tyrosine kinase inhibitors, as well as immune checkpoint inhibitors (ICIs), which have been added to our therapeutic armamentarium. This review examines the influence of HIV infection on HCC development and natural history, summarizes main data on systemic therapies, offers some insight into possible mechanisms of T cell exhaustion and reversal of HIV latency with ICIs and issues about clinical trials enrollment. Nowadays, routine exclusion of HIV-infected patients from clinical trial participation is totally inappropriate, since it leaves a number of patients deprived of life-prolonging therapies.