AGROFORESTRY ADDRESSING SOCIAL AND ENVIRONMENTAL ISSUES IN PARAGUAY

Paraguay is characterized in part by an economy reliant on a massive soy industry and as facing social and economic challenges resulting from highly inequitable distribution of wealth and land ownership, particularly for smallholder farmers in the rural areas of the country. Yerba mate (Ilex paraguariensis), a native tree of which the leaves are used in tea, has become an increasingly common crop grown among common among smallholder farmers (owners of 10 hectares or less) as a viable alternative to soy production on a small scale. In the rural agricultural community of Libertad del Sur, located in the heart of the severely deforested Bosque Atlántico del Alto-Paraná, a series of development initiatives including tree nurseries and agroforestry projects with yerba mate were implemented with involvement of several governmental and nongovernmental organizations. Research was conducted to identify effectiveness of an agroforestry strategy to promote reforestation activities and sustainable agriculture to achieve economic and subsistence goals of the rural population. Despite a severe drought impacting initial research goals, important lessons are considered regarding promotion of development work within the community as well as community perceptions towards development agencies. Pursuit of compromise between community member and agency goals using sustainable agricultural practices is identified as an effective means to promote mutually beneficial development strategies.

Technical advances improved outcome in patients undergoing surgery of the ascending aorta and/or aortic arch: ten years experience

BACKGROUND: Several technical advances in thoracic aortic surgery, such as the use of antegrade cerebral perfusion, avoidance of cross-clamping and the application of glue, have beneficially influenced postoperative outcome. The aim of the present study was to analyse the impact of these developments on outcome of patients undergoing surgery of the thoracic aorta. METHODS AND RESULTS: Between January 1996 and December 2005, 835 patients (37.6%) out of 2215 aortic patients underwent surgery on the thoracic ascending aorta or the aortic arch at our institution. All in-hospital data were assessed. Two hundred and forty-one patients (28.8%) suffered from acute type A dissection (AADA). Overall aortic caseload increased from 41 patients in 1996 to 141 in 2005 (+339%). The increase was more pronounced for thoracic aortic aneurysms (TAA) (+367.9%), than for acute type A aortic dissections (+276.9%). Especially in TAA, combined procedures increased and the amount of patients with impaired left ventricular function (EF <50%) raised up from 14% in 1996 to 24% in 2005. Average age remained stable. Logistic regression curve revealed a significant decrease in mortality (AADA) and in the overall incidence of neurological deficits. CONCLUSIONS: Technical advances in the field of thoracic aortic surgery lead to a decrease of mortality and morbidity, especially in the incidence of adverse neurological events, in a large collective of patients. Long-term outcome and quality of life are better, since antegrade cerebral perfusion has been introduced.

Low-grade endometrial stromal sarcoma with inferior vena cava tumor thrombus and intracardiac extension: radical resection may improve recurrence free survival

BACKGROUND: Endometrial stromal sarcoma (ESS) represents 0.2% of all uterine malignancies. Based on the mitotic activity, a distinction is made between low and high-grade ESS. Although the overall five-year survival rate for low-grade ESS exceeds 80%, about 50% of the patients show tumor recurrence, mostly after a long latency period. Tumor invasion of the great vessels is extremely rare. We describe a patient with advanced low-grade ESS with tumor invasion of the infrarenal aorta and the inferior vena cava. The patient presented with a large tumor thrombus extending from the inferior vena cava into the right atrium. METHODS: Review of literature and identification of 19 patients, including our own case report, with advanced low-grade ESS with invasion of the great vessels and formation of an inferior vena cava tumor thrombus. RESULTS: All 19 patients presented with an abdominal tumor mass and a tumor thrombus protruding into the inferior vena cava. The tumor thrombus extended into the right heart cavities in nine patients reaching the right atrium in four, the right ventricle in three and the pulmonary artery in two patients. There were 5 patients with an advanced primary tumor and 14 patients with an advanced recurrent tumor. Seven patients presented with synchronous metastatic disease and six patients with a pelvic tumor infiltrating the bladder, the rectosigmoid colon or the infrarenal aorta. Mean age at surgery was 45.9+/-12.3 years (median 47, range 25-65 years). Tumor thrombectomy was accomplished by cavatomy or by right atriotomy after installation of a cardiopulmonary bypass. There was no peri-operative mortality and a very low morbidity. Radical tumor resections were achieved in 10 patients. The follow-up for these 10 patients was 2+/-1.3 years (median 2, range 0.3-4.5 years). Nine patients remained recurrence free whereas one patient suffered an asymptomatic local recurrence. CONCLUSIONS: Low-grade ESS is a rare angioinvasive tumor with a high recurrence rate. Resection of an inferior vena cava tumor thrombus, even with extension into the right heart cavities, can be performed safely. Extensive radical surgery is therefore justified in the treatment of advanced tumor manifestations of a low-grade ESS potentially improving recurrence free survival.

Heart rate recovery after exercise in chronic heart failure: Role of vital exhaustion and type D personality

OBJECTIVE: Vital exhaustion and type D personality previously predicted mortality and cardiac events in patients with chronic heart failure (CHF). Reduced heart rate recovery (HRR) also predicts morbidity and mortality in CHF. We hypothesized that elevated levels of vital exhaustion and type D personality are both associated with decreased HRR. METHODS: Fifty-one patients with CHF (mean age 58+/-12 years, 82% men) and left ventricular ejection fraction (LVEF) andard exercise testing before receiving outpatient cardiac rehabilitation. They completed the 9-item short form of the Maastricht Vital Exhaustion Questionnaire and the 14-item type D questionnaire asking about negative affectivity and social inhibition. HRR was calculated as the difference between heart rate at the end of exercise and 1min after abrupt cessation of exercise (HRR-1). Regression analyses were adjusted for gender, age, LVEF, and maximum exercise capacity. RESULTS: Vital exhaustion explained 8.4% of the variance in continuous HRR-1 (p=0.045). For each point increase on the vital exhaustion score (range 0-18) there was a mean+/-SEM decrease of 0.54+/-0.26bpm in HRR-1. Type D personality showed a trend toward statistical significance for being associated with lower levels of HRR-1 explaining 6.5% of the variance (p<0.08). The likelihood of having HRR-1and type D personality were both independently associated with reduced HRR-1. The findings provide a hitherto not explored psychobiological explanation for poor cardiac outcome in patients with CHF.

Prophylactic antibiotics or G-CSF for the prevention of infections and improvement of survival in cancer patients undergoing chemotherapy

BACKGROUND: Febrile neutropenia (FN) and other infectious complications are some of the most serious treatment-related toxicities of chemotherapy for cancer, with a mortality rate of 2% to 21%. The two main types of prophylactic regimens are granulocyte (G-CSF) or granulocyte-macrophage colony stimulating factors (GM-CSF); and antibiotics, frequently quinolones or cotrimoxazole. Important current guidelines recommend the use of colony stimulating factors when the risk of febrile neutropenia is above 20% but they do not mention the use of antibiotics. However, both regimens have been shown to reduce the incidence of infections. Since no systematic review has compared the two regimens, a systematic review was undertaken. OBJECTIVES: To compare the effectiveness of G-CSF or GM-CSF with antibiotics in cancer patients receiving myeloablative chemotherapy with respect to preventing fever, febrile neutropenia, infection, infection-related mortality, early mortality and improving quality of life. SEARCH STRATEGY: We searched The Cochrane Library, MEDLINE, EMBASE, databases of ongoing trials, and conference proceedings of the American Society of Clinical Oncology and the American Society of Hematology (1980 to 2007). We planned to include both full-text and abstract publications. SELECTION CRITERIA: Randomised controlled trials comparing prophylaxis with G-CSF or GM-CSF versus antibiotics in cancer patients of all ages receiving chemotherapy or bone marrow or stem cell transplantation were included for review. Both study arms had to receive identical chemotherapy regimes and other supportive care. DATA COLLECTION AND ANALYSIS: Trial eligibility and quality assessment, data extraction and analysis were done in duplicate. Authors were contacted to obtain missing data. MAIN RESULTS: We included two eligible randomised controlled trials with 195 patients. Due to differences in the outcomes reported, the trials could not be pooled for meta-analysis. Both trials showed non-significant results favouring antibiotics for the prevention of fever or hospitalisation for febrile neutropenia. AUTHORS' CONCLUSIONS: There is no evidence for or against antibiotics compared to G(M)-CSFs for the prevention of infections in cancer patients.

Early serum procalcitonin, interleukin-6, and 24-hour lactate clearance: useful indicators of septic infections in severely traumatized patients

BACKGROUND: Elevated lactate and interleukin-6 (IL-6) levels were shown to correlate with mortality and multiple organ dysfunction in severely traumatized patients. The purpose of this study was to test whether an association exists between 24-hour lactate clearance, IL-6 and procalcitonin (PCT) levels, and the development of infectious complications in trauma patients. METHODS: A total of 1757 consecutive trauma patients with an Injury Severity Score (ISS) > 16 admitted over a 10-year period were retrospectively analyzed over a 21-day period. Exclusion criteria included death within 72 h of admission (24.5%), late admission > 12 h after injury (16%), and age < 16 years (0.5%). Data are stated as the median (range). RESULTS: Altogether, 1032 trauma patients (76.2% male) with an average age of 38 years, a median ISS of 29 (16-75), and an Acute Physiology, Age, and Chronic Health Evaluation (APACHE) II score of 14 (0-40) were evaluated. The in-hospital mortality (>3 days) was 10%. Patients with insufficient 24-hour lactate clearance had a high rate of overall mortality and infections. Elevated early serum procalcitonin on days 1 to 5 after trauma was strongly associated with the subsequent development of sepsis (p < 0.01) but not with nonseptic infections. The kinetics of IL-6 were similar to those of PCT but did differentiate between infected and noninfected patients after day 5. CONCLUSIONS: This study demonstrates that elevated early procalcitonin and IL-6 levels and inadequate 24-hour lactate clearance help identify trauma patients who develop septic and nonseptic infectious complications. Definition of specific cutoff values and early monitoring of these parameters may help direct early surgical and antibiotic therapy and reduce infectious mortality.

The blood-brain and the blood-cerebrospinal fluid barriers: function and dysfunction

The central nervous system (CNS) is tightly sealed from the changeable milieu of blood by the blood-brain barrier (BBB) and the blood-cerebrospinal fluid (CSF) barrier (BCSFB). While the BBB is considered to be localized at the level of the endothelial cells within CNS microvessels, the BCSFB is established by choroid plexus epithelial cells. The BBB inhibits the free paracellular diffusion of water-soluble molecules by an elaborate network of complex tight junctions (TJs) that interconnects the endothelial cells. Combined with the absence of fenestrae and an extremely low pinocytotic activity, which inhibit transcellular passage of molecules across the barrier, these morphological peculiarities establish the physical permeability barrier of the BBB. In addition, a functional BBB is manifested by a number of permanently active transport mechanisms, specifically expressed by brain capillary endothelial cells that ensure the transport of nutrients into the CNS and exclusion of blood-borne molecules that could be detrimental to the milieu required for neural transmission. Finally, while the endothelial cells constitute the physical and metabolic barrier per se, interactions with adjacent cellular and acellular layers are prerequisites for barrier function. The fully differentiated BBB consists of a complex system comprising the highly specialized endothelial cells and their underlying basement membrane in which a large number of pericytes are embedded, perivascular antigen-presenting cells, and an ensheathment of astrocytic endfeet and associated parenchymal basement membrane. Endothelial cell morphology, biochemistry, and function thus make these brain microvascular endothelial cells unique and distinguishable from all other endothelial cells in the body. Similar to the endothelial barrier, the morphological correlate of the BCSFB is found at the level of unique apical tight junctions between the choroid plexus epithelial cells inhibiting paracellular diffusion of water-soluble molecules across this barrier. Besides its barrier function, choroid plexus epithelial cells have a secretory function and produce the CSF. The barrier and secretory function of the choroid plexus epithelial cells are maintained by the expression of numerous transport systems allowing the directed transport of ions and nutrients into the CSF and the removal of toxic agents out of the CSF. In the event of CNS pathology, barrier characteristics of the blood-CNS barriers are altered, leading to edema formation and recruitment of inflammatory cells into the CNS. In this review we will describe current knowledge on the cellular and molecular basis of the functional and dysfunctional blood-CNS barriers with focus on CNS autoimmune inflammation.

Validation of the estimation of physiologic ability and surgical stress (E-PASS) score in liver surgery

BACKGROUND: The estimation of physiologic ability and surgical stress (E-PASS) has been used to produce a numerical estimate of expected mortality and morbidity after elective gastrointestinal surgery. The aim of this study was to validate E-PASS in a selected cohort of patients requiring liver resections (LR). METHODS: In this retrospective study, E-PASS predictor equations for morbidity and mortality were applied to the prospective data from 243 patients requiring LR. The observed rates were compared with predicted rates using Fisher's exact test. The discriminative capability of E-PASS was evaluated using receiver-operating characteristic (ROC) curve analysis. RESULTS: The observed and predicted overall mortality rates were both 3.3% and the morbidity rates were 31.3 and 26.9%, respectively. There was a significant difference in the comprehensive risk scores for deceased and surviving patients (p = 0.043). However, the scores for patients with or without complications were not significantly different (p = 0.120). Subsequent ROC curve analysis revealed a poor predictive accuracy for morbidity. CONCLUSIONS: The E-PASS score seems to effectively predict mortality in this specific group of patients but is a poor predictor of complications. A new modified logistic regression might be required for LR in order to better predict the postoperative outcome.

Expression and regulation of antimicrobial peptide rCRAMP after bacterial infection in primary rat meningeal cells

Bacterial meningitis is characterized by an inflammation of the meninges and continues to be an important cause of mortality and morbidity. Meningeal cells cover the cerebral surface and are involved in the first interaction between pathogens and the brain. Little is known about the role of meningeal cells and the expression of antimicrobial peptides in the innate immune system. In this study we characterized the expression, secretion and bactericidal properties of rat cathelin-related antimicrobial peptide (rCRAMP), a homologue of the human LL-37, in rat meningeal cells after incubation with different bacterial supernatants and the bacterial cell wall components lipopolysaccharide (LPS) and peptidoglycan (PGN). Using an agar diffusion test, we observed that supernatants from meningeal cells incubated with bacterial supernatants, LPS and PGN showed signs of antimicrobial activity. The inhibition of rCRAMP expression using siRNA reduced the antimicrobial activity of the cell culture supernatants. The expression of rCRAMP in rat meningeal cells involved various signal transduction pathways and was induced by the inflammatory cytokines interleukin-1, -6 and tumor necrosis factor alpha. In an experimental model of meningitis, infant rats were intracisternally infected with Streptococcus pneumoniae and rCRAMP was localized in meningeal cells using immunohistochemistry. These results suggest that cathelicidins produced by meningeal cells play an important part in the innate immune response against pathogens in CNS bacterial infections.