In situ short-term responses of Amazonian understory plants to elevated CO2.

The response of plants to increasing atmospheric CO2 depends on the ecological context where the plants are found. Several experiments with elevated CO2 (eCO2) have been done worldwide, but the Amazonian forest understory has been neglected. As the central Amazon is limited by light and phosphorus, understanding how understory responds to eCO2 is important for foreseeing how the forest will function in the future. In the understory of a natural forest in the Central Amazon, we installed four open-top chambers as control replicates and another four under eCO2 (+250 ppm above ambient levels). Under eCO2, we observed increases in carbon assimilation rate (67%), maximum electron transport rate (19%), quantum yield (56%), and water use efficiency (78%). We also detected an increase in leaf area (51%) and stem diameter increment (65%). Central Amazon understory responded positively to eCO2 by increasing their ability to capture and use light and the extra primary productivity was allocated to supporting more leaf and conducting tissues. The increment in leaf area while maintaining transpiration rates suggests that the understory will increase its contribution to evapotranspiration. Therefore, this forest might be less resistant in the future to extreme drought, as no reduction in transpiration rates were detected.

Diagnosis and Management of a Massive Eight-Centimeter Acquired Tracheoesophageal Fistula.

Here, we present the case of a 61-year-old veteran Hispanic male with recurrent aspiration pneumonitis, aerophagia, tympanic abdominal bloating, and a positive Ono's sign; symptoms present were secondary to diagnosed tracheoesophageal fistulas (TEFs). TEFs are abnormal connections between the esophagus and the trachea. In adult cases, several risk factors have been identified for acquired cases, which include infection, trauma, and cancer. Diagnosis of TEF can be challenging and, in most cases, requires high suspicion. Currently, there are no established guidelines for diagnosing and managing TEF. Clinical assessment and various imaging techniques are essential in the diagnostic process. This article will discuss the etiology, clinical presentation, diagnostic approaches, and management options for acquired TEFs.

Impact of Lymphocyte and Neutrophil Counts on Mortality Risk in Severe Community-Acquired Pneumonia with or without Septic Shock.

BACKGROUND: Community-acquired pneumonia (CAP) is a frequent cause of death worldwide. As recently described, CAP shows different biological endotypes. Improving characterization of these endotypes is needed to optimize individualized treatment of this disease. The potential value of the leukogram to assist prognosis in severe CAP has not been previously addressed. METHODS: A cohort of 710 patients with CAP admitted to the intensive care units (ICUs) at Hospital of Mataró and Parc Taulí Hospital of Sabadell was retrospectively analyzed. Patients were split in those with septic shock (n = 304) and those with no septic shock (n = 406). A single blood sample was drawn from all the patients at the time of admission to the emergency room. ICU mortality was the main outcome. RESULTS: Multivariate analysis demonstrated that lymphopenia <675 cells/mm3 or <501 cells/mm3 translated into 2.32- and 3.76-fold risk of mortality in patients with or without septic shock, respectively. In turn, neutrophil counts were associated with prognosis just in the group of patients with septic shock, where neutrophils <8850 cells/mm3 translated into 3.6-fold risk of mortality. CONCLUSION: lymphopenia is a preserved risk factor for mortality across the different clinical presentations of severe CAP (sCAP), while failing to expand circulating neutrophils counts beyond the upper limit of normality represents an incremental immunological failure observed just in those patients with the most severe form of CAP, septic shock.

Treatment of Hypertensive Cardiogenic Edema with Intravenous High-Dose Nitroglycerin in a Patient Presenting with Signs of Respiratory Failure: A Case Report and Review of the Literature.

BACKGROUND Pulmonary edema is the accumulation of fluid in the lung secondary to increased hydrostatic pressure. Hypertensive cardiogenic pulmonary edema presents with a sudden onset of severe dyspnea, tachycardia, and tachypnea, and can occur when the systolic blood pressure exceeds 160 mmHg in association with acute decompensated congestive cardiac failure (CCF). A case is presented of hypertensive cardiogenic pulmonary edema treated with high-dose nitroglycerin and includes a review of the literature. CASE REPORT A 63-year-old Hispanic male with a medical history of hypertension, coronary artery disease, heart failure with a reduced ejection fraction of 35%, chronic kidney disease (CKD) and diabetes mellitus, presented as an emergency with acute, severe dyspnea. The patient was initially managed with 100% oxygen supplementation and intravenous (IV) high-dose nitroglycerin (30 mcg/min), which was titrated every 3 minutes, increasing by 15 mcg/min until a dose of 120 mcg/min was reached. After 18 minutes of aggressive therapy, the patient's condition improved and he no longer required mechanical ventilation. CONCLUSIONS Hypertensive cardiogenic pulmonary edema is a challenging clinical condition that should be diagnosed and managed as early as possible, and distinguished from respiratory failure due to other causes. Although hypertensive cardiogenic pulmonary edema is usually managed acutely with high-dose diuretics, this case has highlighted the benefit of high-dose IV nitroglycerin, and review of the literature supports this treatment approach.