The co-occurrence of mtDNA mutations on different oxidative phosphorylation subunits, not detected by haplogroup analysis, affects human longevity and is population specific

To re-examine the correlation between mtDNA variability and longevity, we examined mtDNAs from samples obtained from over 2200 ultranonagenarians (and an equal number of controls) collected within the framework of the GEHA EU project. The samples were categorized by high-resolution classification, while about 1300 mtDNA molecules (650 ultranonagenarians and an equal number of controls) were completely sequenced. Sequences, unlike standard haplogroup analysis, made possible to evaluate for the first time the cumulative effects of specific, concomitant mtDNA mutations, including those that per se have a low, or very low, impact. In particular, the analysis of the mutations occurring in different OXPHOS complex showed a complex scenario with a different mutation burden in 90+ subjects with respect to controls. These findings suggested that mutations in subunits of the OXPHOS complex I had a beneficial effect on longevity, while the simultaneous presence of mutations in complex I and III (which also occurs in J subhaplogroups involved in LHON) and in complex I and V seemed to be detrimental, likely explaining previous contradictory results. On the whole, our study, which goes beyond haplogroup analysis, suggests that mitochondrial DNA variation does affect human longevity, but its effect is heavily influenced by the interaction between mutations concomitantly occurring on different mtDNA genes.

Clinical severity of ischemic stroke and neural damage biomarkers in the acute setting: the STROke MArkers (STROMA) study

BACKGROUND

Stroke is a leading cause of long-term morbidity and mortality affecting several hundred-thousand people annually in the Western Countries. Various panels of biomarkers of neural damage have been developed and validated. The primary objective of this investigation was to measure the correlation between the clinical severity of stroke and the serum/plasma concentrations of neural damage biomarkers.

METHODS

A prospective investigation was conducted on a panel of biomarkers composed of S100β, matrix metalloproteinase-9 (MMP-9), N-terminal pro-B-type natriuretic peptide (NT pro-BNP) and D-dimer at admission and after 24 hours, in a cohort patients with a confirmed diagnosis of stroke in an emergency setting (STROke-MArkers STROMA).

RESULTS

A total of 58 consecutive patients were enrolled, no participant was excluded; according to clinical severity measured by National Institute of Health Stroke Scale (NIHSS) there were 29 minor strokes, 24 moderate, 3 moderate-severe, 2 severe. The Spearman's rank correlation test was used to assess the relationship between the baseline NIHSS value and the concentrations of the four biomarkers: all the studied biomarkers showed a statistically significant correlation with baseline NIHSS at 24 hours. A multivariate ordinal regression model was used to analyze the correlation of markers with stroke severity, stratified, according to NIHSS score: MMP-9 and S100β showed a statistically significant correlation after 24 hours.

CONCLUSION

MMP-9, S100β, NT pro-BNP and D-dimer showed a good correlation with the clinical severity of stroke which may become an additional resource in the acute patient evaluation and potentially follow-up.

Analysis of population substructure in two sympatric populations of Gran Chaco, Argentina

Sub-population structure and intricate kinship dynamics might introduce biases in molecular anthropology studies and could invalidate the efforts to understand diseases in highly admixed populations. In order to clarify the previously observed distribution pattern and morbidity of Chagas disease in Gran Chaco, Argentina, we studied two populations (Wichí and Criollos) recruited following an innovative bio-cultural model considering their complex cultural interactions. By reconstructing the genetic background and the structure of these two culturally different populations, the pattern of admixture, the correspondence between genealogical and genetic relationships, this integrated perspective had the power to validate data and to link the gap usually relying on a singular discipline. Although Wichí and Criollos share the same area, these sympatric populations are differentiated from the genetic point of view as revealed by Non Recombinant Y Chromosome genotyping resulting in significantly high Fst values and in a lower genetic variability in the Wichí population. Surprisingly, the Amerindian and the European components emerged with comparable amounts (20%) among Criollos and Wichí respectively. The detailed analysis of mitochondrial DNA showed that the two populations have as much as 87% of private haplotypes. Moreover, from the maternal perspective, despite a common Amerindian origin, an Andean and an Amazonian component emerged in Criollos and in Wichí respectively. Our approach allowed us to highlight that quite frequently there is a discrepancy between self-reported and genetic kinship. Indeed, if self-reported identity and kinship are usually utilized in population genetics as a reliable proxy for genetic identity and parental relationship, in our model populations appear to be the result not only and not simply of the genetic background but also of complex cultural determinants. This integrated approach paves the way to a rigorous reconstruction of demographic and cultural history as well as of bioancestry and propensity to diseases of Wichí and Criollos.

Essential amino acid supplementation in patients with severe COPD: a step towards home rehabilitation

BACKGROUND

Pulmonary Rehabilitation ("Rehabilitation") can improve both lung function and quality of life in patients suffering from chronic obstructive pulmonary disease (COPD) even if only a very small proportion of patients have access to Rehabilitation. Supplementation of Essential Amino Acids (EAAs) might allow COPD patients to achieve some typical Rehabilitation outcomes such as a better physical performance and an improved health status.

METHODS

88 COPD out-patients (GOLD class 3-4) with a body mass index (BMI) < 23 Kg/m2 were randomised to receive EAAs (n = 44) or placebo (n = 44) for twelve weeks. Primary outcome measures were changes in both physical activities in daily life (measured by Sense Wear Armband in terms of mean steps walked in one week) and in quality of life (measured by the St George's Respiratory Questionnaire, SGRQ).

RESULTS

After 12 weeks, the physical performance was significantly increased vs baseline only in patients who received EAAs (1140.33 +/- 524.69 and 638.68 +/- 662.1 steps/day, respectively; p = 0.02), being also the comparison vs the placebo group highly significant (p = 0.003). Similarly, the SGRQ score improved significantly only in EAA patients (69.35 +/- 9.51 vs baseline 72.04 +/- 8.62; p < 0.01), and changes were significantly different from those measured in the placebo group (p < 0.001). Furthermore, when compared to those who received placebo, EAAs patients significantly increased their fat-free mass (p = 0.04), muscle strength (p < 0.01), saturation of oxygen (p = 0.05), serum albumin (p < 0.001), and also ameliorated their original cognitive dysfunction (p = 0.02).

CONCLUSIONS

Oral supplementation with EAAs contribute to improve the daily-life performance in domiciliary severe COPD patients who can not enter any Rehabilitation programme, together with their quality of life; nutritional and cognitive status, and muscle strength.

Immune system, cell senescence, aging and longevity--inflamm-aging reappraised

Inflamm-aging, that is the age-associated inflammatory status, is considered one of the most striking consequences of immunosenescence, as it is believed to be linked to the majority of age-associated diseases sharing an inflammatory basis. Nevertheless, evidence is emerging that inflamm-aging is at least in part independent from immunological stimuli. Moreover, centenarians who avoided or delayed major inflammatory diseases display markers of inflammation. In this paper we proposed a reappraisal of the concept of inflamm-aging, suggesting that its pathological effects can be independent from the total amount of pro-inflammatory mediators, but they would be rather associated with the anatomical district and type of cells where they are produced and where they primarily act.

Plasma renin concentration as a predictor of outcome in a medical intensive care setting: a retrospective pilot study

BACKGROUND

Renin and aldosterone are involved in an organ perfusion pathway that may be an estimate of disease severity. The primary objective was to explore the relationship between outcome and aldosterone and renin levels at medical intensive care unit (MICU) admissions in comparison to SAPS II scores.

METHODS

This retrospective study was conducted on patients admitted to the adult MICU during 12 months. Exclusion: subjects with creatinine >176 mmol/l, chronic arrhythmia and ACE-inhibitor therapy. Admission aldosterone and renin plasma levels were measured and SAPS II scores were calculated.

RESULTS

Eighty-two patients were included. Only the plasma renin median concentration difference between survivors and non-survivors was significant (P=0.0168). The area under the ROC curve for mortality and plasma renin concentration was similar to that of SAPS II. The correlation between mortality and renin >84 pg/mL showed an odds ratio of 5.78±3.45, P=0.003.

CONCLUSION

Renin was correlated to outcome in critically ill medical patients.

How new imaging techniques can aid in defining the cardiovascular profile of the high-risk patient

Cardiovascular prevention has been developed in the last eight years producing an ever increasing amount of data requiring frequent updating. Studies using angiography to determine change in coronary obstruction have indicated progression, stabilization, or regression of coronary lesions associated with changes in plasma lipids and lipoproteins. Moreover, the guidelines on arterial hypertension published in 2007 listed the risk factors affecting prognosis but even by 2009 an update modified not only the list of risks, but even the philosophy behind the thought process which introduced as essential element in the prognosis of hypertension the ascertained existence of a damaged organ. Thus, the documentation of atherosclerotic vascular disease (plaques) and the quantification of its extension in the arterial tree became a determinant in the definition of cardiovascular risk. Magnetic Resonance (MRI) and coronary computed tomography (coro CT) applied to the heart and large vessels are the most promising methods.

Measurement of the neutron radius of 208Pb through parity violation in electron scattering

We report the first measurement of the parity-violating asymmetry A(PV) in the elastic scattering of polarized electrons from 208Pb. A(PV) is sensitive to the radius of the neutron distribution (R(n)). The result A(PV)=0.656±0.060(stat)±0.014(syst) ppm corresponds to a difference between the radii of the neutron and proton distributions R(n)-R(p)=0.33(-0.18)(+0.16) fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus.

Search for a new gauge boson in electron-nucleus fixed-target scattering by the APEX experiment

We present a search at the Jefferson Laboratory for new forces mediated by sub-GeV vector bosons with weak coupling α' to electrons. Such a particle A' can be produced in electron-nucleus fixed-target scattering and then decay to an e + e- pair, producing a narrow resonance in the QED trident spectrum. Using APEX test run data, we searched in the mass range 175-250 MeV, found no evidence for an A'→ e+ e- reaction, and set an upper limit of α'/α ~/= 10(-6). Our findings demonstrate that fixed-target searches can explore a new, wide, and important range of masses and couplings for sub-GeV forces.

[Lesser validity of urinary benzene than S-phenylmercapturic acid for measuring occupational and environmental exposure to very low concentrations of benzene]

AIM

To study the validity of urinary benzene as a biomarker of low and very low exposure to this toxicant, as compared with t,t-muconic acid (t,t-MA) and S-phenylmercapturic acid (SPMA), also taking into account the influence of cigarette smoking and co-exposure to toluene on the urinary excretion of benzene.

MATERIALS AND METHODS

The results obtained in two different studies were compared: in the first, workers occupationally exposed to low concentrations of benzene (18 fuel tanker drivers and 23 filling station attendants) were compared with 31 controls and in the second, workers exposed to very low concentrations of benzene (the same 23 filling station attendants) were compared with the 31 controls. Exposure to airborne benzene and toluene was monitored with passive personal samplers (Radiello). Then the urine collected at the end of the work shift was analyzed for t,t-MA, SPMA and urinary benzene. All participants also filled out a questionnaire about their lifestyle habits.

RESULTS

There were no differences among the three groups in terms of age and smoking habit. Occupational exposure to benzene and toluene and the urinary concentrations of t,t-MA, SPMA and urinary benzene were higher in the fuel tanker drivers than the filling station attendants and higher in the latter than in the controls. Cigarette smoking was found to be associated with urinary excretion of t,t-MA, SPMA and urinary benzene at both low and very low exposure to benzene. The biomarkers t,t-MA, SPMA and urinary benzene were almost always correlated, for both low and very low exposure to benzene. Notably, for low exposure to benzene a dependency relation was found with the levels of t,t-MA, SPMA and urinary benzene on both cigarette smoking and airborne benzene, whereas for very low exposure to benzene there was a dependency relation of SPMA on cigarette smoking and airborne benzene, of urinary benzene only on cigarette smoking and of t,t-MA on none of the variables considered.

CONCLUSIONS

For occupational exposure to low concentrations of benzene, urinary benzene and SPMA showed a comparable validity, while for exposure to very low concentrations of this toxicant the validity of SPMA was confirmed while urinary benzene was found to be less useful. Cigarette smoking was the main factor conditioning the excretion of all the biomarkers of benzene in conditions of both low and very low exposure to the toxicant, so for the analysis of occupational exposure to benzene it is best to recommend abstention from smoking at least in the hours immediately before urine collection.

Applicability of urinary benzene to biological monitoring of occupational and environmental exposure to very low benzene concentrations

OBJECTIVE

To verify whether urinary benzene is an applicable biomarker of occupational exposure to very low concentrations of benzene, considering the influence of cigarette smoke and benzene-toluene co-exposure.

MATERIALS AND METHODS

23 filling station attendants with occupational exposure to benzene and 31 controls were analyzed. Occupational and environmental exposure was monitored and t,t-muconic acid (t,t-MA), S-phenylmercapturic acid (SPMA), urinary benzene and creatinine in the urine samples were tested.

RESULTS

Occupational exposure to benzene and toluene was significantly higher in the filling station attendants than in the controls, whereas t,t-MA, SPMA and urinary benzene were not different in the two groups. Instead, the smoker group showed significantly higher values for the above biomarkers than the non-smoker group, each of which included both exposed workers and controls. SPMA was dependent on airborne benzene and cigarette smoking, and urinary benzene only on cigarette smoking, while t,t-MA was not dependent on either of these variables.

CONCLUSIONS

At very low concentrations of occupational exposure to benzene, urinary benzene is less valid than SPMA as a biomarker, even if both are strongly influenced by smoking habit. Abstention from smoking should therefore be recommended for at least two hours before urine collection.