Dust temporal and spatial deposition affected by climate and soil mineralogical and chemical properties in a semi-arid area.

The important process of aerosol dusting is of economic, environmental and heath significance. The objective was to investigate the climatic parameters including rainfall (R), wind speed (WS), temperature (T), and relative humidity (RH), as well as soil mineralogical and chemical properties affecting dust deposition rate (DDR), in a unique and rarely studied area, the Kuhdasht watershed (456 km2) of Lorestan province, Iran. Data were collected seasonally using glass-traps inserted in ten research stations to indicate DDR seasonal and spatial variations using ARC-GIS. The spatial distribution of organic matter (OM), clay and CaCO3, and the mineralogical properties (using diffractograms obtained by XRD) of the dust and soil samples were determined. The city had the highest DDR decreasing toward the mountains. Spring (3.28-4.18 ton/km2) and autumn (1.82-2.52 ton/km2) resulted in the highest and the least DDR, respectively. The diffractograms indicated the sources of dust were local or from out of the borders. The clay minerals (kaolinite and illite) and the evaporating minerlas (gypsum, calcite, dolomite, and halite), detected in the soil and dust samples indicated their contribution to the process of DDR. According to the regression models and the correlation coefficients, DDR was highly and significantly correlated with R (R2= 0.691), WS (0.685) and RH (0.463) indicating such parameters can importantly affect DDR in the semi-arid areas.

A study on alpha-terpineol in Alzheimer's disease with the use of rodent in vivo model, restraint stress effect and in vitro Amyloid beta fibrils

Abstract Alzheimer's disease (AD) is a neurological disorder in which the neuronal degeneration is associated with inflammatory processes and oxidative stress. Since alpha-terpineol was shown to possess antioxidant and anti-inflammatory effects, the administration of this compound was studied on a rat model of AD. To create this model, Aβ1-42 was injected into the hippocampus of male Wistar rats. Generated AD models were divided into simple AD models and AD models in which short-term immobilization stress was added. Preventive and therapeutic (post-AD induction) effects of alpha-terpineol consumption (100 mg/Kg) were subsequently investigated in AD models, which were compared with control groups. Biochemical factors (superoxide dismutase and malondialdehyde), histological manifestations (amyloid plaques and neuron counts) and possible memory impairment (shuttle-box experiment) were investigated in all groups. For the in vitro experiment, alpha-terpineol effect was checked on Aβ1-42 fibril formation. In preventive and therapeutic modes, alpha-terpineol consumption could improve neurogenesis and long-term memory while reducing amyloid plaque counts and ameliorating biochemical factors (higher levels of superoxide dismutase and malondialdehyde and reduced levels of MDA). In vitro, shorter fibrillar structures were formed in the presence of alpha-terpineol, which indicates an anti-amyloid effect for this compound. In conclusion, alpha-terpineol significantly counteracted AD consequences.

Facial Fractures After Geriatric Ground-Level Falls Are a Marker of Functional Decline and Warrant Trauma Center Admission.

Ground-level falls (GLFs) are a frequent source of injury in the geriatric population. Facial fractures (FFs) are one subsequent injury that can occur and may be an important marker of functional decline. We conducted a retrospective analysis over a 6-year period of patients 65 years and older sustaining one or more FFs due to a GLF (n = 28). Demographics, comorbidities, FF patterns, concomitant injuries, procedures, and outcomes were analyzed. The mean age was 80.0 ± 8.2 years, 64% were male, 12 patients (43%) were on oral anticoagulants prior to injury, and mean injury severity score was 8.3 ± 7.0. Five patients (18%) had LeFort fractures (1 with LeFort I, 4 with LeFort II), and 5 (18%) had isolated mandible fractures (2 were bilateral). Nearly half of all patients suffered neurological injury (concussion: 18%, intracranial hemorrhage: 29%). Average hospital length of stay (LOS) was 4.0 ± 2.9 days. Eight patients (29%) required intensive care unit (ICU) admission with an average ICU-LOS of 2.8 ± 1.2 days. Surgical management was required in 4 patients (14%). More than half of the patients returned home (54%), 25% were discharged to a skilled nursing facility, 4% to rehabilitation, 7% to hospice, and 7% expired. Nearly one-third of patients required discharge to a higher level of care facility than their location prior to injury. GLF-induced FFs are often associated with significant injuries and serve as an indicator of functional decline. These injuries warrant trauma center admission for comprehensive evaluation and management.

Facial fractures and associated injuries in high- versus low-energy trauma: all are not created equal.

INTRODUCTION: Facial fractures (FFs) occur after high- and low-energy trauma; differences in associated injuries and outcomes have not been well articulated. OBJECTIVE: To compare the epidemiology, management, and outcomes of patients suffering FFs from high-energy and low-energy mechanisms. METHODS: We conducted a 6-year retrospective local trauma registry analysis of adults aged 18-55 years old that suffered a FF treated at the Santa Barbara Cottage Hospital. Fracture patterns, concomitant injuries, procedures, and outcomes were compared between patients that suffered a high-energy mechanism (HEM: motor vehicle crash, bicycle crash, auto versus pedestrian, falls from height > 20 feet) and those that suffered a low-energy mechanism (LEM: assault, ground-level falls) of injury. RESULTS: FFs occurred in 123 patients, 25 from an HEM and 98 from an LEM. Rates of Le Fort (HEM 12% vs. LEM 3%, P = 0.10), mandible (HEM 20% vs. LEM 38%, P = 0.11), midface (HEM 84% vs. LEM 67%, P = 0.14), and upper face (HEM 24% vs. LEM 13%, P = 0.217) fractures did not significantly differ between the HEM and LEM groups, nor did facial operative rates (HEM 28% vs. LEM 40%, P = 0.36). FFs after an HEM event were associated with increased Injury Severity Scores (HEM 16.8 vs. LEM 7.5, P <0.001), ICU admittance (HEM 60% vs. LEM 13.3%, P <0.001), intracranial hemorrhage (ICH) (HEM 52% vs. LEM 15%, P <0.001), cervical spine fractures (HEM 12% vs. LEM 0%, P = 0.008), truncal/lower extremity injuries (HEM 60% vs. LEM 6%, P <0.001), neurosurgical procedures for the management of ICH (HEM 54% vs. LEM 36%, P = 0.003), and decreased Glasgow Coma Score on arrival (HEM 11.7 vs. LEM 14.2, P <0.001). CONCLUSION: FFs after HEM events were associated with severe and multifocal injuries. FFs after LEM events were associated with ICH, concussions, and cervical spine fractures. Mechanism-based screening strategies will allow for the appropriate detection and management of injuries that occur concomitant to FFs. TYPE OF STUDY: Retrospective cohort study. LEVEL OF EVIDENCE: Level III.

Preoperative Antibiotics for Dialysis Access Surgery: Are They Necessary?

BACKGROUND: Current guidelines recommend preoperative antibiotics in all vascular surgery cases. However, we hypothesize that patients undergoing arteriovenous fistula (AVF) and arteriovenous graft (AVG) creation have low rates of postoperative surgical site infection (SSI) and that preoperative antibiotic prophylaxis in these patients may not be necessary. METHODS: This is a retrospective review of all patients who underwent AVF and AVG creation from November 2014 through July of 2016 at a single institution. At our institution, preoperative antibiotic use is surgeon dependent. Patients who received preoperative antibiotics were compared with those who did not. The primary outcome measured was the development of postoperative SSI. RESULTS: There were 304 patients identified and 294 patients with 30 day postoperative follow-up. Of the 294 patients, 23 (7.8%) received an AVG, and 271 (92.2%) received an AVF. There were 244 (83%) patients who received preoperative antibiotics and 50 (17%) who did not. Overall, there were 2 (0.68%) SSIs identified. Both patients with postoperative SSI underwent AVF creation and received preoperative antibiotics. There was no statistically significant difference in SSI rate between antibiotic and nonantibiotic groups (P = 1.0), and no difference when comparing patients that received AVG (0%) and AVF (0.73%) (P = 1.0). CONCLUSIONS: The rate for postoperative SSI following hemodialysis access surgery is very low both for patients undergoing AVF and AVG. Furthermore, there was no difference in SSI rate between antibiotic and nonantibiotic groups. Given these findings, we conclude that preoperative antibiotics for AVF creation may not be necessary.

Factors Associated with Early Thrombosis after Arteriovenous Fistula Creation.

BACKGROUND: Arteriovenous fistulas (AVF) are the preferred modality for hemodialysis access. Early thrombosis hampers development of a working AVF. We endeavored to determine the incidence and identify factors associated with early thrombosis of AVF and to determine salvage rates following thrombosis, at a high-volume hemodialysis access center. METHODS: Retrospective review of autologous AVF was created between November 2014 and July 2016 at a single center. Early thrombosis was defined as thrombosis that occurred within 30 days of surgery. RESULTS: There were 291 AVFs. The median age was 54.7 years, and 192 patients (66%) were male. Early postoperative AVF thrombosis was noted in 5 (1.7%) cases. Factors associated with early thrombosis on univariate analysis included previous access surgery (P = 0.02) and absence of a good intraoperative thrill (P = 0.006). Intraoperative protamine use trended toward significance (P = 0.06). Factors that were not significant included gender, diabetes, dialysis at time of surgery, fistula configuration, and systemic heparin use. None of the thrombosed fistulas were salvaged. CONCLUSIONS: Early thrombosis is a relatively rare complication of AVF creation at a high-volume center. Previous access surgery and absence of good thrill at conclusion of the procedure are associated with early thrombosis.

Predictors of Steal in Hemodialysis Access.

Pathological steal is an uncommon but devastating complication after the creation of arteriovenous access for hemodialysis. In this study, we sought to assess predictors of clinically significant steal syndrome and to further evaluate the outcome of differing surgical treatment approaches. A retrospective analysis was performed of 282 consecutive patients undergoing hemodialysis access at a single center from November 2014 to April 2016. Adequate follow-up to assess for the development of steal was obtained in 237 patients. One hundred and fifty-seven (66%) patients were male, 152 (64%) Hispanic, and 164 (69%) had diabetes. Forty-three (18%) had prior access procedures. Autologous fistula was created in 218 patients (92%). Pathologic steal occurred in 15 patients (6.7%). On univariate analysis, significant predictors of steal included female sex [P = 0.03, odds ratio (OR) = 3.3, CI [1.1-9]), no systemic heparin at operation (P = 0.02, OR = 5.0, CI [1.4-10]), use of angiotensin-converting enzyme inhibitor (P = 0.003, OR = 5.6, CI [1.7-18.6]), and increased vein size (3.1 vs 4.1 mm P = 0.01). Twelve patients had steal managed with an intervention, but only one patient received distal revascularization. Furthermore, we identify key predictors of clinically significant steal syndrome while demonstrating that distal revascularization and/or fistula ligation are rarely indicated treatment modalities.

Outcomes after External Iliac and Femoral Vascular Injuries.

BACKGROUND: Vascular injuries occurring at the junction of the trunk and lower extremity are uncommon yet challenging because of their location and potential for associated truncal injuries. The purpose of this study was to examine and compare outcomes among patients sustaining external iliac and femoral vascular injuries. METHODS: We performed a 13-year retrospective analysis of our level 1 trauma center database to identify and compare patients with external iliac and femoral vessel injuries. Multiple logistic regression analysis was performed to identify independent predictors for mortality. RESULTS: During the study period, 135 patients with a median (interquartile range [IQR]) age of 25 (20-35) years were identified with external iliac (n = 29) and femoral vascular injuries (n = 106). The majority were male (85.9%) with a penetrating mechanism (84.5%), and the median (IQR) Injury Severity Score (ISS) was 16 (11-26). The overall mortality rate was 14.1%. In comparison with patients with femoral vascular injuries, patients with external iliac injuries presented with higher ISS (25 vs. 16, P < 0.001), lower Glasgow Coma Scale (14 vs. 15, P = 0.001) and had a higher incidence of mortality (41.4% vs. 6.6%, P < 0.001) and disability (13.8% vs. 1%, P = 0.007). Shunts were used in only 7 patients (5.2%). Stepwise logistic regression consistently identified external iliac injury (odds ratio, 15.6; 95% confidence interval, 1.72-141, P = 0.014 in best-fitted model) as independently associated with mortality. CONCLUSIONS: In comparison with femoral vascular injuries, external iliac vascular injuries are associated with higher blood loss, more intense resuscitation, higher disability and mortality in patients sustaining junctional groin injuries. Early recognition and application of damage control techniques and resuscitative practices may result in improved outcomes.

Predictors of Severity in Diabetic Foot Infections.

BACKGROUND: Diabetic foot infections (DFIs) constitute a large burden of the morbidity of diabetes, with more than 70,000 lower-extremity amputations (LEA) performed annually in the United States. A necrotizing infection signifies the most severe form of infection and is a key factor in the decision to proceed to LEA for source control. Key clinical and laboratory variables can assist in the identification of necrotizing infections; however, the effect of diabetes on these variables is unknown. Given the increased level and complexity of metabolic derangements in diabetic patients, we sought to examine characteristics predictive of necrotizing infection in patients with DFI who underwent LEA. METHODS: We performed a single-institutional retrospective analysis of diabetic patients who underwent a LEA for DFIs over an 18-month period. Patients with necrotizing infection on final pathology were compared with patients without this pathologic finding. Multivariate analysis was performed to identify independent predictors of necrotizing infection. RESULTS: Of 183 patients, 57 (31%) had evidence of necrotizing infections. Factors associated with necrotizing infection on univariate analysis were the presence of bullae (11% vs. 2%; odds ratio [OR] = 4.8, P = 0.03), a higher mean admission white blood cell count (WBC; 15 vs. 12, P = 0.002), a lower mean absolute sodium (132 vs. 134, P = 0.01), a higher hemoglobin A1C (11.3 vs. 10.3, P = 0.05), hyperglycemia (289 vs. 248, P = 0.04), elevated C-reactive protein (20 vs. 11, P = 0.02), and the presence of Pseudomonas aeruginosa on final tissue culture (12.3 vs. 1.6, P = 0.004). These patients were taken to surgery more rapidly (22.5 vs. 31 hr, P = 0.04), and they had a longer postoperative stay (7 vs. 4 days, P = 0.02). On multivariate analysis, an elevated WBC was predictive of necrotizing infection (OR = 1.1, P = 0.01), whereas alcohol use was found to be protective (OR = 0.3, P = 0.04). CONCLUSIONS: Clinical and laboratory variables known to be associated with necrotizing infections among the general population appear to be predictive of disease severity among patients undergoing amputation for DFIs. Identification of these abnormalities preoperatively may allow for improved operative planning, shared decision making, and resource management. Prospective validation of these findings is potentially warranted.

Postoperative antibiotics are not associated with decreased wound complications among patients undergoing appendectomy for complicated appendicitis.

BACKGROUND: The objective of this study was to determine the role of postoperative antibiotics in reducing complications in patients undergoing appendectomy for complicated appendicitis. METHODS: We performed a 5-year retrospective cohort study of adult patients who underwent appendectomy for acute appendicitis. Patients with complicated appendicitis (perforated or gangrenous) were analyzed on the basis of whether they received postoperative antibiotics. Main outcome measures were wound complications, length of stay (LOS), and readmission to hospital. RESULTS: Of 410 patients with complicated appendicitis, postoperative antibiotics were administered to 274 patients (66.8%). On univariate and multivariate analyses, postoperative antibiotics were not associated with decreased wound complications or readmission, but independently predicted an increased LOS (P = .01). CONCLUSIONS: Among patients with complicated appendicitis, postoperative antibiotics were not associated with a decrease in wound complications but did result in an increased hospital LOS.

Diagnostic accuracy of frozen section of central nervous system lesions: a 10-year study.

OBJECTIVE: Definitive diagnosis of the central nervous system (CNS) lesions is unknown prior to histopathological examination. To determine the method and the endpoint for surgery, intraoperative evaluation of the lesion helps the surgeon. In this study, the diagnostic accuracy and pitfalls of using frozen section (FS) of CNS lesions is determined. MATERIALS & METHODS: In this retrospective study, we analyzed the results of FS and permanent diagnoses of all CNS lesions by reviewing reports from 3 general hospitals between March 2001 and March 2011. RESULTS: 273 cases were reviewed and patients with an age range from 3 to 77 years of age were considered. 166 (60.4%) had complete concordance between FS and permanent section diagnosis, 83 (30.2%) had partial concordance, and 24 cases (9.5%) were discordant. Considering the concordant and partially concordant cases, the accuracy rate was 99.5%, sensitivity was 91.4%, specificity was 99.7%, and positive and negative predictive values were 88.4% and 99.8%, respectively. CONCLUSION: Our results show high sensitivity and specificity of FS diagnosis in the evaluation of CNS lesions. A Kappa agreement score of 0.88 shows high concordance for FS results with permanent section. Pathologist's misinterpretation, small biopsy samples (not representative of the entire tumor), suboptimal slides, and inadequate information about tumor location and radiologic findings appear to be the major causes for these discrepancies indicated from our study.

Irrigation of abdomen with imipenem solution decreases surgical site infections in patients with perforated appendicitis: a randomized clinical trial.

BACKGROUND: Perforated appendicitis is one of the most common causes of acute abdomen requiring emergent surgery for immediate appendectomy and peritoneal cavity irrigation; however, the efficacy of irrigation with antibiotic solutions is controversial. OBJECTIVES: The aim of this study was to assess the efficacy of imipenem solution irrigation on post-operative surgical site infections (SSIs), hospital length of stay, and hospital costs. We hypothesized that there would be lower rate of SSIs, a shorter hospital stay, and lower hospital cost in patients with perforated appendicitis who received peritoneal cavity irrigation with imipenem solution in comparison to their counterparts who received irrigation with normal saline. PATIENTS AND METHODS: In this randomized single-blind parallel-group clinical trial, we enrolled 90 patients with perforated appendicitis with 12-50 years of age and randomly allocated them into experimental group (n = 45) and control group (n = 45). The control group received peritoneal irrigation with normal saline (0.9%) and experimental group underwent peritoneal irrigation with imipenem solution (1 mg/mL). All surgical procedures were performed in Imam Reza Hospital of Kermanshah University of Medical Sciences. The study primary outcome was surgical site infections (including wound infection and abdominal abscess) and the secondary outcomes were length of hospital stay and hospital cost. Chi-squared and t-tests were used to analyze the study data. RESULTS: Imipenem solution irrigation was associated with significant clinical improvement at one-month follow-up. The experimental group presented with significantly lower rate of SSIs and shorter length of hospital stay. The experimental group had lower rate of SSIs compared to the control group (4.4% vs. 22.2%, respectively) (p= 0.013). The duration of hospital stay was nearly one day longer in control group (5.84 ± 2.58 days) vs. experimental group (4.91 ± 1.29 days) (P = 0.034), and hospital costs were $50 lower in experimental group ($500 ± $292) vs. control group ($450 ± $170) (P = 0.281). CONCLUSIONS: The study findings revealed that peritoneal lavage with imipenem solution (1 mg/mL) decreases the rate of post-operative SSIs in patients with perforated appendicitis in comparison to patients irrigated with normal saline alone. These patients also had shorter hospital stay, and lower hospital costs.