Arroyo del Vizcaíno,Uruguay: a fossil-rich 30-ka-old megafaunal locality with cut-marked bones

Human–megafauna interaction in the Americas has great scientific and ethical interest because of its implications on Pleistocene extinction. The Arroyo del Vizcaíno site near Sauce, Uruguay has already yielded over 1000 bones belonging to at least 27 individuals, mostly of the giant sloth Lestodon. The assemblage shows some taphonomic features suggestive of human presence, such as a mortality profile dominated by prime adults and little evidence of major fluvial transport. In addition, several bones present deep, asymmetrical, microstriated, sharp and shouldered marks similar to those produced by human stone tools. A few possible lithic elements have also been collected, one of which has the shape of a scraper and micropolish consistent with usage on dry hide. However, the radiocarbon age of the site is unexpectedly old (between 27 and 30 thousand years ago), and thus may be important for understanding the timing of the peopling of America.     

Hospital Admissions for Hypertensive Crisis in the Emergency Departments: A Large Multicenter Italian Study

Epidemiological data on the impact of hypertensive crises (emergencies and urgencies) on referral to the Emergency Departments (EDs) are lacking, in spite of the evidence that they may be life-threatening conditions. We performed a multicenter study to identify all patients aged 18 years and over who were admitted to 10 Italian EDs during 2009 for hypertensive crises (systolic blood pressure ≥220 mmHg and/or diastolic blood pressure ≥120 mmHg). We classified patients as affected by either hypertensive emergencies or hypertensive urgencies depending on the presence or the absence of progressive target organ damage, respectively. Logistic regression analysis was then performed to assess variables independently associated with hypertensive emergencies with respect to hypertensive urgencies. Of 333,407 patients admitted to the EDs over the one-year period, 1,546 had hypertensive crises (4.6/1,000, 95% CI 4.4–4.9), and 23% of them had unknown hypertension. Hypertensive emergencies (n = 391, 25.3% of hypertensive crises) were acute pulmonary edema (30.9%), stroke (22.0%,), myocardial infarction (17.9%), acute aortic dissection (7.9%), acute renal failure (5.9%) and hypertensive encephalopathy (4.9%). Men had higher frequency than women of unknown hypertension (27.9% vs 18.5%, p<0.001). Even among known hypertensive patients, a larger proportion of men than women reported not taking anti-hypertensive drug (12.6% among men and 9.4% among women (p<0.001). Compared to women of similar age, men had higher likelihood of having hypertensive emergencies than urgencies (OR = 1.34, 95% CI 1.06–1.70), independently of presenting symptoms, creatinine, smoking habit and known hypertension. This study shows that hypertensive crises involved almost 5 out of 1,000 patients-year admitted to EDs. Sex differences in frequencies of unknown hypertension, compliance to treatment and risk of hypertensive emergencies might have implications for public health programs.     

Lactoferrin binding sites and nuclear localization in K562(S) cells.

Lactoferrin, a single chain cationic glycoprotein, present in the secondary granules of neutrophils, acts as a negative feedback regulator of myelopoiesis. Specific receptors for lactoferrin were detected on the surface of different hematopoietic cell types. The influence of lactoferrin on cell growth in culture has been reported. Interactions of lactoferrin with DNA were also demonstrated. In the present paper we confirm the presence of lactoferrin specific binding sites on K562 cells and we estimate the number of binding sites and the dissociation constant. By Western blotting analysis performed on K562 lysates we find a band of about 120 kDa responsible for specific binding of lactoferrin. We also show that lactoferrin, after binding at the cell surface, is internalized in a temperature dependent way and is immunologically detectable as a DNA-linked protein in nuclear extracts.     

Acute and Chronic Experimental Trypanosoma cruzi Infection in the Rat. Response to Systemic Treatment with Recombinant Rat Interferon-Gamma

We examined the effects of recombinant rat inteferon-gamma (IFN-γ) injections on the parasitologic, serologic, immunologic and histopathologic features of acute and chronic experimental Trypanosoma cruzi (T. cruzi) infections in “l” rats. Upon infection at weaning, two rat groups were allocated to receive a 20-day cycle of IFN-γ injections, 20,000 IU/rat each, which started at 1, and 7 days post-infection (pi). Treatment with IFN-γ, initiated at either 1 or 7 days pi, resulted in comparatively lower peak parasitemias (P<0.02) but in similar levels of anti-T. cruzi circulating antibodies and serum IFN-γ activities. The latter appeared significantly increased during acute infection whereas biologically active tumor necrosis factor was virtually undetectable in serum from infected rats regardless of whether they had been given IFN-γ or not. The prevalence of chronic focal myocarditis in IFN-γ-treated infected rats showed no differences with respect to the one recorded in control-infected counterparts. The inverse CD4/CD8 ratio of spleen and lymph node T cells that usually accompanies chronic infection was reversed by IFN-γ. Mononuclear cells carrying class III-A and I-E molecules, that were found to have increased at both compartments, appeared also modified upon IFN-γ treatment with an overincrease of I-A-positive cells, and a normalization of I-E-bearing cells.     

Demonstration of actin in neurosecretory cells by treatment with nitrobenzoxadiazole-phallacidin

Serial sections containing neurosecretory cells from chicken hypothalamus were cut after fixation in formaldehyde and embedding in paraffin. Sections were exposed to NBD-Ph (nitrobenzoxadiazole-phallacidin) and showed evidence of containing actin. By using a medium with sodium borohydride, non-specific fluorescence could be excluded.     

Intraindividual variation of beta 2-adrenergic receptors on mononuclear leukocytes and their relationships with endogenous plasma catecholamines in man.

The interindividual and intraindividual variations of both MNL beta 2-adrenergic receptor density and dissociation constant of binding were evaluated in 19 healthy volunteers. In addition the possible relationships between catecholamine plasma levels and MNL beta 2-adrenergic receptor density were studied in 8 of these subjects. The volunteers were studied three times with ten days' interval. There was a significant inverse relationship between receptor density and norepinephrine plasma levels, only. Neither epinephrine nor dopamine were correlated with receptor density. Interindividual coefficient of variation was 29.57%. The mean value of the intraindividual coefficients of variation was 14.1%, while the mean value of the analytical coefficients of variation was 10%. Our results are at some variance with data in the literature and may contribute to elucidate the role of MNL beta 2-adrenergic receptors as an index of sympathetic function in man.     

Biological control of great brome (<Emphasis Type="Italic">Bromus diandrus</Emphasis>) in durum wheat (<Emphasis Type="Italic">Triticum durum</Emphasis>): specificity,physiological traits and impact on plant growth and root architecture of the fluorescent pseudomonad strain X33d

The rhizobacterial strain X33d was previously shown to suppress the growth of the weed great brome (Bromus diandrus Roth.). The aim of this work was to identify X33d, characterize its physiological activities, assess its specificity on different non-target crops, and its impact on the growth and the root architecture of great brome and durum wheat (Triticum durum Desf.) grown alone and together. Based on 16S rDNA sequencing, X33d was identified as Pseudomonas trivialis. The specificity assay, performed on a mixture of soil/sand/peat, highlighted the suppressive activity of P. trivialis X33d against great brome and the promoting effect on most of the considered crops, especially durum wheat. Although the growth of durum wheat on quartz sand was unaffected, P. trivialis X33d suppressed the growth and affected the root architecture of great brome, especially when co-seeded with durum wheat. Great brome plants inoculated with X33d and co-seeded with durum wheat showed low root biomass, short root systems and low surface area, volume and number of tips. Moreover, P. trivialis X33d synthesized indole-acetic acid (IAA) that could be involved both in great brome growth suppression and durum wheat growth promotion. Our results indicate that P. trivialis X33d could be exploited as a potential biocontrol agent against great brome without affecting the durum wheat growth. These results are discussed in relation to the competitive capability of great brome towards durum wheat.