Droughts impede water balance recovery from fires in the Western United States.

A steady rise in fires in the Western United States, coincident with intensifying droughts, imparts substantial modifications to the underlying vegetation, hydrology and overall ecosystem. Drought can compound the ecosystem disturbance caused by fire, although how these compound effects on hydrologic and ecosystem recovery vary among ecosystems is poorly understood. Here we use remote sensing-derived high-resolution evapotranspiration (ET) estimates from before and after 1,514 fires to show that ecoregions dominated by grasslands and shrublands are more susceptible to drought, which amplifies fire-induced ET decline and, subsequently, shifts water flux partitioning. In contrast, severely burned forests recover from fire slowly or incompletely, but are less sensitive to dry extremes. We conclude that moisture limitation caused by droughts influences the dynamics of water balance recovery in post-fire years. This finding explains why moderate to extreme droughts aggravate impacts on the water balance in non-forested vegetation, while moisture accessed by deeper roots in forests helps meet evaporative demands unless severe burns disrupt internal tree structure and deplete fuel load availability. Our results highlight the dominant control of drought on altering the resilience of vegetation to fires, with critical implications for terrestrial ecosystem stability in the face of anthropogenic climate change in the West.

Interconnected hydrologic extreme drivers and impacts depicted by remote sensing data assimilation.

Hydrologic extremes often involve a complex interplay of several processes. For example, flood events can have a cascade of impacts, such as saturated soils and suppressed vegetation growth. Accurate representation of such interconnected processes while accounting for associated triggering factors and subsequent impacts of flood events is difficult to achieve with conceptual hydrological models alone. In this study, we use the 2019 flood in the Northern Mississippi and Missouri Basins, which caused a series of hydrologic disturbances, as an example of such a flood event. This event began with above-average precipitation combined with anomalously high snowmelt in spring 2019. This series of anomalies resulted in above normal soil moisture that prevented crops from being planted over much of the corn belt region. In the present study, we demonstrate that incorporating remote sensing information within a hydrologic modeling system adds substantial value in representing the processes that lead to the 2019 flood event and the resulting agricultural disturbances. This remote sensing data infusion improves the accuracy of soil moisture and snowmelt estimates by up to 16% and 24%, respectively, and it also improves the representation of vegetation anomalies relative to the reference crop fraction anomalies.

A Large Hydatid Cyst in the Brain of a 10-year Child.

Hydatid cyst is the larval form of the parasite, echinococcus granulosus. We operated upon a case of a giant hydatid cyst in the left cerebral hemisphere of a 10-year male child. The patient presented to us with a history of headache, vomiting, vertigo and difficulty in walking. On the examination, there was hemiparesis on the right side and left-sided papilledema. The CT scan showed a large extra-axial cystic lesion in the left frontotemporoparietal area. Craniotomy and excision of the cyst by hydro-dissection was performed. The patient recovered uneventfully and was discharged. Albendazole was given postoperatively for a period of one month. The follow-up CT scan, performed after three months, showed complete resolution of the disease. Key Words: Hydatid cyst, Echinococcus granulosus, Brain, Children.

Realizing ecosystem-safe hydropower from dams.

For clean hydropower generation while sustaining ecosystems, minimizing harmful impacts and balancing multiple water needs is an integral component. One particularly harmful effect not managed explicitly by hydropower operations is thermal destabilization of downstream waters. To demonstrate that the thermal destabilization by hydropower dams can be managed while maximizing energy production, we modelled thermal change in downstream waters as a function of decision variables for hydropower operation (reservoir level, powered/spillway release, storage), forecast reservoir inflow and air temperature for a dam site with in situ thermal measurements. For data-limited regions, remote sensing-based temperature estimation algorithm was established using thermal infrared band of Landsat ETM+ over multiple dams. The model for water temperature change was used to impose additional constraints of tolerable downstream cooling or warming (1-6 °C of change) on multi-objective optimization to maximize hydropower. A reservoir release policy adaptive to thermally optimum levels for aquatic species was derived. The novel concept was implemented for Detroit dam in Oregon (USA). Resulting benefits to hydropower generation strongly correlated with allowable flexibility in temperature constraints. Wet years were able to satisfy stringent temperature constraints and produce substantial hydropower benefits, while dry years, in contrast, were challenging to adhere to the upstream thermal regime.

Outcomes of In-Hospital Cardiopulmonary Resuscitation in Morbidly Obese Patients.

OBJECTIVES: This study sought to assess the impact of morbid obesity on outcomes in patients with in-hospital cardiac arrest (IHCA). BACKGROUND: Obesity is associated with increased risk of out-of-hospital cardiac arrest; however, little is known about survival of morbidly obese patients with IHCA. METHODS: Using the Nationwide Inpatient Sample database from 2001 to 2008, we identified adult patients undergoing resuscitation for IHCA, including those with morbid obesity (body mass index ≥40 kg/m2) by using International Classification of Diseases 9th edition codes and clinical outcomes. Outcomes including in-hospital mortality, length of stay, and discharge dispositions were identified. Logistic regression model was used to examine the independent association of morbid obesity with mortality. RESULTS: Of 1,293,071 IHCA cases, 27,469 cases (2.1%) were morbidly obese. The overall mortality was significantly higher for the morbidly obese group than for the nonobese group experiencing in-hospital non-ventricular fibrillation (non-VF) (77% vs. 73%, respectively; p = 0.006) or VF (65% vs. 58%, respectively; p = 0.01) arrest particularly if cardiac arrest happened late (>7 days) after hospitalization. Discharge to home was significantly lower in the morbidly obese group (21% vs. 31%, respectively; p = 0.04). After we adjusted for baseline variables, morbid obesity remained an independent predictor of increased mortality. Other independent predictors of mortality were age and severe sepsis for non-VF and VF group and venous thromboembolism, cirrhosis, stroke, malignancy, and rheumatologic conditions for non-VF group. CONCLUSIONS: The overall mortality of morbidly obese patients after IHCA is worse than that for nonobese patients, especially if IHCA occurs after 7 days of hospitalization and survivors are more likely to be transferred to a skilled nursing facility.

Infections in Liver Disease.

Infectious complications are common occurrences in end-stage liver disease (ESLD). Frequent infections precipitate decompensation of liver disease leading to acute or chronic liver failure, organ dysfunction, de-listing from transplant, and major morbidity and mortality. The spectrum of microorganisms has shifted with the emergence of multidrug-resistant strains, which has major implications for both therapy and prophylaxis. Cirrhosis is often associated with an underlying noninfectious systemic inflammatory state that makes diagnosis of infections particularly challenging. Adequate resuscitation and timely administration of appropriate antibiotics are pivotal to improved outcomes from infections in ESLD.

Severe sepsis in hematopoietic stem cell transplant recipients*.

OBJECTIVE: Severe sepsis requires timely management and has high mortality if care is delayed. Hematopoietic stem cell transplant recipients are more likely to be immunocompromised and are predisposed to serious infections. Reports of outcomes of severe sepsis in this population are limited to data from single, tertiary care centers, and national outcomes data are missing. DESIGN: Retrospective analysis of an administrative database. SETTING: Twenty percent of community hospitals in United States, excluding federal hospitals. SUBJECT: Patients with severe sepsis. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: We used International Classification of Diseases, 9th Edition, Clinical Modification codes indicating the presence of sepsis and organ system failure to identify hospitalizations for severe sepsis between 2000 and 2008. We also used International Classification of Diseases, 9th Edition, Clinical Modification codes to identify hematopoietic stem cell transplant recipients. We compared outcomes of hematopoietic stem cell transplant recipients with severe sepsis during engraftment and subsequent admissions with a non-hematopoietic stem cell transplant cohort and excluded solid-organ transplantation from this cohort. We used mixed effect, multivariate logistic regression modeling with propensity score adjustment to examine factors associated with mortality of severe sepsis in hematopoietic stem cell transplant recipients. A total of 21,898 hematopoietic stem cell transplant recipients with severe sepsis were identified. The frequency of severe sepsis in hematopoietic stem cell transplant recipients was five times higher when compared with the non-hematopoietic stem cell transplant cohort. The unadjusted mortality was 32.9% in non-hematopoietic stem cell transplant cohort, which was similar to autologous hematopoietic stem cell transplant recipients (30.1%) and those who did not develop graft-versus-host disease (35%). Mortality was significantly higher in allogeneic transplants (55.1%, p < 0.001) and in those who developed graft-versus-host disease (47.9%, p < 0.001). After adjustment, during engraftment admission, the odds of in-hospital mortality in allogeneic hematopoietic stem cell transplant (odds ratio, 3.81; 95% CI, 2.39-6.07) and autologous hematopoietic stem cell transplant (odds ratio, 1.28; 95% CI, 1.06-1.53) recipients was significantly higher than non-hematopoietic stem cell transplant patients. Similarly, in subsequent admissions, hematopoietic stem cell transplant recipients with graft-versus-host disease (odds ratio, 2.14; 95% CI, 1.88-2.45) and without graft-versus-host disease (odds ratio, 1.35; 95% CI, 1.19-1.54) had significantly higher odds of mortality than non-hematopoietic stem cell transplant patients. Among patients with hematopoietic stem cell transplant, persons with autologous hematopoietic stem cell transplant and those without graft-versus-host disease fared better as compared with their allogeneic and graft-versus-host disease counterparts. CONCLUSIONS: Hematopoietic stem cell transplant recipients are more likely to develop severe sepsis and die following a severe sepsis episode than nontransplant patients. Autologous hematopoietic stem cell transplant recipients and those who do not develop graft-versus-host disease have significantly better outcomes than allogeneic and graft-versus-host disease patients.

Effect of a rapid response team on patient outcomes in a community-based teaching hospital.

BACKGROUND: Rapid response teams have been adopted across hospitals to reduce the rate of inpatient cardiopulmonary arrest. Yet, data are not uniform on their effectiveness across university and community settings. OBJECTIVE: The objective of our study was to determine the impact of rapid response teams on patient outcomes in a community teaching hospital with 24/7 resident coverage. METHODS: Our retrospective chart review of preintervention-postintervention data included all patients admitted between January 2004 and April 2006. Rapid response teams were initiated in March 2005. The outcomes of interest were inpatient mortality, unexpected transfer to the intensive care unit, code blue (cardiac or pulmonary arrest) per 1000 discharges, and length of stay in the intensive care unit. RESULTS: Rapid response teams were activated 213 times during the intervention period. There was no statistically significant difference in inpatient mortality (3.13% preintervention versus 2.91% postintervention), code blue calls (3.09 versus 2.89 per 1000 discharges), or unexpected transfers of patients to the intensive care unit (15.8% versus 15.5%). CONCLUSIONS: The implementation of a rapid response team did not appear to affect overall mortality and code blue calls in a community-based hospital with 24/7 resident coverage.

Functional connectivity of the cortical swallowing network in humans.

INTRODUCTION: Coherent fluctuations of blood oxygenation level dependent (BOLD) signal have been referred to as "functional connectivity" (FC). Our aim was to systematically characterize FC of underlying neural network involved in swallowing, and to evaluate its reproducibility and modulation during rest or task performance. METHODS: Activated seed regions within known areas of the cortical swallowing network (CSN) were independently identified in 16 healthy volunteers. Subjects swallowed using a paradigm driven protocol, and the data analyzed using an event-related technique. Then, in the same 16 volunteers, resting and active state data were obtained for 540 s in three conditions: 1) swallowing task; 2) control visual task; and 3) resting state; all scans were performed twice. Data was preprocessed according to standard FC pipeline. We determined the correlation coefficient values of member regions of the CSN across the three aforementioned conditions and compared between two sessions using linear regression. Average FC matrices across conditions were then compared. RESULTS: Swallow activated twenty-two positive BOLD and eighteen negative BOLD regions distributed bilaterally within cingulate, insula, sensorimotor cortex, prefrontal and parietal cortices. We found that: 1) Positive BOLD regions were highly connected to each other during all test conditions while negative BOLD regions were tightly connected among themselves; 2) Positive and negative BOLD regions were anti-correlated at rest and during task performance; 3) Across all three test conditions, FC among the regions was reproducible (r>0.96, p<10(-5)); and 4) The FC of sensorimotor region to other regions of the CSN increased during swallowing scan. CONCLUSIONS: 1) Swallow activated cortical substrates maintain a consistent pattern of functional connectivity; 2) FC of sensorimotor region is significantly higher during swallow scan than that observed during a non-swallow visual task or at rest.

Reproducibility of swallow-induced cortical BOLD positive and negative fMRI activity.

Functional MRI (fMRI) studies have demonstrated that a number of brain regions (cingulate, insula, prefrontal, and sensory/motor cortices) display blood oxygen level-dependent (BOLD) positive activity during swallow. Negative BOLD activations and reproducibility of these activations have not been systematically studied. The aim of our study was to investigate the reproducibility of swallow-related cortical positive and negative BOLD activity across different fMRI sessions. We studied 16 healthy volunteers utilizing an fMRI event-related analysis. Individual analysis using a general linear model was used to remove undesirable signal changes correlated with motion, white matter, and cerebrospinal fluid. The group analysis used a mixed-effects multilevel model to identify active cortical regions. The volume and magnitude of a BOLD signal within each cluster was compared between the two study sessions. All subjects showed significant clustered BOLD activity within the known areas of cortical swallowing network across both sessions. The cross-correlation coefficient of percent fMRI signal change and the number of activated voxels across both positive and negative BOLD networks were similar between the two studies (r ≥ 0.87, P < 0.0001). Swallow-associated negative BOLD activity was comparable to the well-defined "default-mode" network, and positive BOLD activity had noticeable overlap with the previously described "task-positive" network. Swallow activates two parallel cortical networks. These include a positive and a negative BOLD network, respectively, correlated and anticorrelated with swallow stimulus. Group cortical activity maps, as well as extent and amplitude of activity induced by volitional swallowing in the cortical swallowing network, are reproducible between study sessions.

Clostridium difficile infection in hospitalized liver transplant patients: a nationwide analysis.

The incidence of Clostridium difficile infection (CDI) is increasing among hospitalized patients. Liver transplantation (LT) patients are at higher risk for acquiring CDI. Small, single-center studies (but no nationwide analyses) have assessed this association. We used the Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project (2004-2008) for this retrospective, cross-sectional study. Patients with any discharge diagnosis of LT composed the study population, and they were identified with International Classification of Diseases, Ninth Revision, Clinical Modification codes. Those with a discharge diagnosis of CDI were considered cases. Our primary outcomes were the prevalence of CDI and the effects of CDI on inpatient mortality. Our secondary outcomes included the length of stay and hospitalization charges. A regression analysis was used to derive odds ratios (ORs) adjusted for potential confounders. There were 193,174 discharges with a diagnosis of LT from 2004 to 2008. The prevalence of CDI was 2.7% in the LT population and 0.9% in the non-LT population (P < 0.001). Most of the LT patients were 50 to 64 years old. LT patients had higher odds of developing CDI [OR = 2.88, 95% confidence interval (CI) = 2.68-3.10]. Increasing age and increasing comorbidity (including inflammatory bowel disease and nasogastric tube placement) were also independent CDI risk factors. CDI was associated with a higher mortality rate: 5.5% for LT patients with CDI versus 3.2% for LT-only patients (adjusted OR = 1.70, 95% CI = 1.29-2.25). In conclusion, the prevalence of CDI is higher for LT patients versus non-LT patients (2.7% versus 0.9%). CDI is an independent risk factor for mortality in the LT population.

Chronic kidney disease and end-stage renal disease predict higher risk of mortality in patients with primary upper gastrointestinal bleeding.

BACKGROUND: The outcome of gastrointestinal bleeding in chronic kidney disease (CKD) and end-stage renal disease (ESRD) patients is difficult to discern from the literature. Many publications are small, single-center series or are from an era prior to advanced interventional endoscopy, widespread use of proton pump inhibitors or treatment for Helicobacter pylori infections. In this study, we quantify the role of CKD and ESRD as independent predictors of mortality in patients admitted to the hospital with a principal diagnosis of primary upper gastrointestinal bleeding (UGIB). METHODS: We used the Nationwide Inpatient Sample that contains data on approximately 8 million admissions in 1,000 hospitals chosen to approximate a 20% stratified sample of all US facilities. Patients discharged with the principal diagnosis of primary UGIB, CKD or ESRD were identified through the ninth revision of the International Classification of Diseases, clinical modification (ICD-9-CM) codes. The outcome variables included frequency and in-hospital mortality of UGIB in CKD and ESRD patients as compared to non-CKD patients and were analyzed using logistic regression modeling. RESULTS: In 2007, out of a total of 398,213 admissions with a diagnosis of primary UGIB, 35,985 were in CKD, 14,983 in ESRD, and 347,245 in non-renal disease groups. The OR for primary UGIB hospitalization in CKD and ESRD was 1.30 (95% CI 1.17-1.46) and 1.84 (95% CI 1.61-2.09), respectively. The corresponding all-cause mortality OR was 1.47 (95% CI 1.21-1.78) and 3.02 (95% CI 2.23-4.1), respectively. CONCLUSION: Patients with CKD or ESRD admitted with primary UGIB have up to three times higher risk of all-cause in-hospital mortality, warranting heightened vigilance by their clinicians.

Renal involvement in non-Hodgkin's lymphoma: the Shaukat Khanum experience.

BACKGROUND: Primary lymphoma of genitourinary system is rare as these organs do not contain lymphoid tissue, however secondary involvement often occurs. The most commonly affected genitourinary organ is the kidney. METHODS: Medical records of 901 patients with documented NHL seen at Shaukat Khanum Memorial Cancer Hospital & Research Center during 1995-2003 were studied for the incidence, histopathological, clinical and radiological correlation of renal involvement in NHL. RESULTS: 19(2.1%) patients had renal involvement. Male to female ratio was 3.75:1. Histology was diffuse large cell lymphoma in 12(63%) patients. IPI was High, High intermediate and Low intermediate in 17(89.5%) patients. Radiologically, 5(26.5%) patients had the disease above the diaphragm, 2(10.5%) patients had disease below the diaphragm while 12(63%) had disease on both sides of the diaphragm. 11(58%) showed complete response, 1(5.5%) showed partial response while 7(36.8%) showed progressive disease. CONCLUSION: Majority of patients with renal involvement had low intermediate or higher IPI compatible with significant progression rate. The findings and disease behavior in our population is comparable to those quoted in English literature. Radiological tools have made it easier to monitor disease response and renal biopsy is seldom required.