Seasonal variation of surface radiation and energy balances over two contrasting areas of the seasonally dry tropical forest (Caatinga) in the Brazilian semi-arid.

Arid and semi-arid environments correspond to one-third of the Earth's terrestrial surface. In these environments, precipitation is an essential and limiting element for vegetation growth and ecosystem biomass productivity. The semi-arid region of Brazil comprises around 11.5% of the national territory, where the Caatinga biome originally composed ~ 76% of this area, with water deficit as a prominent feature, annual rainfall lower than 800 mm, temperatures ranging between 25 and 30 °C, and potential evapotranspiration higher than 2000 mm/year. Research on the dynamics of mass and heat fluxes through techniques such as eddy covariance (EC) has contributed to estimate the magnitude and seasonal patterns of turbulent exchanges between ecosystems and the atmosphere. This study was conducted in an area of dense Caatinga (DC) and another of sparse Caatinga (SC) from 2013 to 2014. It was observed that albedo (α) and net radiation (Rn) were higher in the SC compared with DC since the magnitude of incoming shortwave radiation was higher in this area. It was found that most of the Rn is converted to sensible heat flux (H), mainly during the dry period in the SC, about 50% for H and 20% for λE. The energy balance closure showed that the turbulent fluxes (H + λE) were underestimated in comparison to the available energy at the surface (Rn - G). We also observed that this discrepancy was higher in the DC area, corresponding to ~ 30%.

Seasonal variation in net ecosystem CO2 exchange of a Brazilian seasonally dry tropical forest.

Forest ecosystems sequester large amounts of atmospheric CO2, and the contribution from seasonally dry tropical forests is not negligible. Thus, the objective of this study was to quantify and evaluate the seasonal and annual patterns of CO2 exchanges in the Caatinga biome, as well as to evaluate the ecosystem condition as carbon sink or source during years. In addition, we analyzed the climatic factors that control the seasonal variability of gross primary production (GPP), ecosystem respiration (Reco) and net ecosystem CO2 exchange (NEE). Results showed that the dynamics of the components of the CO2 fluxes varied depending on the magnitude and distribution of rainfall and, as a consequence, on the variability of the vegetation state. Annual cumulative NEE was significantly higher (p < 0.01) in 2014 (-169.0 g C m-2) when compared to 2015 (-145.0 g C m-2) and annual NEP/GPP ratio was 0.41 in 2014 and 0.43 in 2015. Global radiation, air and soil temperature were the main factors associated with the diurnal variability of carbon fluxes. Even during the dry season, the NEE was at equilibrium and the Caatinga acted as an atmospheric carbon sink during the years 2014 and 2015.

First-in-human phase 0 study of 111In-CHX-A"-DTPA trastuzumab for HER2 tumor imaging.

INTRODUCTION: Tumors over-expressing the human epithelial receptor 2 (HER2) or exhibiting amplification or mutation of its proto-oncogene have a poorer prognosis. Using trastuzumab and/or other HER2 targeted therapies can increase overall survival in patients with HER2(+) tumors making it critical to accurately identify patients who may benefit. We report on a Phase 0 study of the imaging agent, 111In-CHX-A"-DTPA trastuzumab, in patients with known HER2 status to evaluate its safety and biodistribution and to obtain preliminary data regarding its ability to provide an accurate, whole-body, non-invasive means to determine HER2 status. METHODS: 111In-CHX-A"-DTPA trastuzumab was radiolabeled on-site and slowly infused into 11 patients who underwent single (n=5) or multiple (n=6) ɣ-camera (n=6) and/or SPECT (n=8) imaging sessions. RESULTS: No safety issues were identified. Visual and semi-quantitative imaging data were concordant with tissue HER2 expression profiling in all but 1 patient. The biodistribution showed intense peak liver activity at the initial imaging timepoint (3.3h) and a single-phase clearance fit of the average time-activity curve (TAC) estimated t1/2=46.9h (R2=0.97; 95%CI 41.8 to 53h). This was followed by high gastrointestinal (GI) tract activity peaking by 52h. Linear regression predicted GI clearance by 201.2h (R2 =0.96; 95%CI 188.5 to 216.9h). Blood pool had lower activity with its maximum on the initial images. Non-linear regression fit projected a t1/2=34.2h (R2 =0.96; 95%CI 25.3 to 46.3h). Assuming linear whole-body clearance, linear regression projected complete elimination (x-intercept) at 256.5hr (R2=0.96; 95%CI 186.1 to 489.2h). CONCLUSION: 111In-CHX-A"-DTPA trastuzumab can be safely imaged in humans. The biodistribution allowed for visual and semiquantitative analysis with results concordant with tissue expression profiling in 10 of 11 patients. Advances in Knowledge and Implications for Patient Care Using readily available components and on-site radiolabeling 111In-CHX-A"-DTPA trastuzumab SPECT imaging may provide an economical, non-invasive means to detect HER2 over-expression.

Controlled Study of Correlation of Biomechanical Profile of Hemiparetic Patients with Distance Travelled in Six Minutes.

The six-minute walking test (6MWT) is used to assess exercise tolerance that is associated with motor function of the lower limbs in hemiparetic patients. It is suggested that, for post-stroke subjects, performance in the 6MWT may be limited by biomechanical and cardiovascular factors. Our aim is to determine the correlation between the six-minute walk distance (6MWD) and the biomechanical profile of hemiparetic patients. During this cross-sectional controlled study, 10 hemiparetic patients with heart failure underwent 6MWT (ATS protocol). Tonus (Ashworth Scale) and goniometry of the lower limbs were measured. The average of 6MWD in two tests was 279±8 m. There was a negative correlation between the degree of spasticity for both the sural triceps (r=-0.57, P<0.05), quadriceps (r=-0.58, P<0.05) and the limitation in ankle dorsiflexion and the 6MWD (r=-0.76, P<0.05). Also, there was correlation between hip extension and ankle dorsiflexion limitations with 6MWD (r=0.66, P<0.05), (r=0.77, P<0.05). The negative correlation between the highest spasticity in paretic limb and the 6MWD and the correlation between the lower movement range of paretic hip and ankle suggest association with these factors and gait velocity in 6MWT. Loss percentage represents the percentage calculation between distance traveled and the distance predicted achieved by patients. In this study, the negative correlation between the percentage of loss of 6MWD and the limitation in the ankle dorsiflexion movement suggests that for a minor motion arch of the ankle, there is a higher percentage of walking distance loss foretold.

Comparison of once-daily cephalosporin regimens for community-acquired lower respiratory tract infections in patients with chronic lung disease.

The efficacy of cefonicid and of ceftriaxone, administered once daily for the treatment of lower respiratory tract bacterial infections (pneumonia or bronchitis), was evaluated and compared in 118 patients with chronic lung disease. The patients were randomly assigned to receive 1 gm of either drug, intravenously or intramuscularly, daily for three to 11 days (mean, seven days). Pathogenic bacteria were isolated from sputum in 59% of patients; Haemophilus influenzae and Streptococcus pneumoniae predominated. Clinical cure or improvement was noted in 95% and 93% of patients treated with cefonicid and ceftriaxone, respectively, and bacteriologic cure or improvement in 69% and 81% (the differences were not significant). Side effects were infrequent and similar in the two treatment groups, except that diarrhea was more common in the ceftriaxone group (11%, versus 4.4% in the cefonicid group). It is concluded that patients with chronic lung disease who experience acute exacerbations associated with infection caused by H influenzae or S pneumoniae, or other susceptible organisms, can be effectively treated with once-daily administration of either cefonicid or ceftriaxone.

Ultrastructural abnormalities of the carotid body in sudden infant death syndrome.

The carotid bodies of four infants who died of sudden infant death syndrome (SIDS) were compared, using electron microscopic techniques, with the carotid bodies of various control subjects. In the SIDS patients, there was a marked reduction or absence of the dense cytoplasmic granules of the carotid chemorecptor cells, as well as a reduction in cell number and size. These ultrastructural abnormalities may be pathophysiologically related to SIDS. A defect in this respiratory control organ could block normal stimulation of respiration during the periods of hypoxia that occur during episodes of sleep apnea in infancy. Further studies by electron microscopy are required to confirm degranulation of the carotid body as a pathognomonic sign of SIDS. Screening of high-risk infants should be directed at studying the carotid body and its mediated responses to hypoxia.

Fatal case of influenza pneumonia with suprainfection by multiple bacteria and Herpes simplex virus.

A case of influenza pneumonia is described in which death occurred from persistence of the influenza infection and suprainfection with two bacteria, Staphylococcus aureus and Escherichia coli, and another virus, Herpes simplex. Of additional interest were the observations that this overwhelming illness developed in a previously healthy person, that typical influenza virus particles were present in antemortem lung tissue, and that the patient died despite 6 days of extracorporeal membrane oxygenation and corticosteroids.