Management of injured patients who were Jehovah's Witnesses, where blood transfusion may not be an option: a retrospective review.

INTRODUCTION: Management of major haemorrhage as a result of trauma is particularly challenging when blood is not an option (BNAO). Evidence on therapeutic strategies in this situation is limited. The aim of this study was to evaluate the management and outcomes of patients who identified themselves as Jehovah's Witnesses (who usually refuse blood products) with traumatic haemorrhage at an Australian major trauma centre. METHODS: A retrospective review of patients from The Alfred Trauma Registry was conducted, including patients who were Jehovah's Witnesses presenting between January 2010 and January 2017. We examined demographics, injury characteristics, clinical progress, therapeutic interventions and outcomes at hospital discharge. RESULTS: There were 34 patients meeting inclusion criteria, with 50% suffering major trauma. Anaemia was a clinical problem for 13 (38·2%) patients, with haemoglobin levels reaching a nadir of 69·7 g/l (95% CI: 56·7-82·7) on average 5·1 days (95% CI: 2·5-7·7) post admission. Various strategies were employed to reduce blood loss including six (46·2%) patients receiving tranexamic acid, nine (29·2%) patients receiving oral or intravenous iron and five (38·5%) receiving erythropoietin. Three patients received packed red cells, and two patients received synthetic haemoglobin-based oxygen carriers. CONCLUSIONS: Numerous therapeutic strategies were employed inconsistently in this unique population of patients. Augmenting circulatory volume with an oxygen carrier acceptable to JW patients presents a novel approach to be considered in adjunct to other strategies. An international resource centre would assist clinicians faced with anaemia and BNAO.

Early start of the West Nile fever transmission season 2018 in Europe.

In Europe, surveillance indicates that the 2018 West Nile fever transmission season started earlier than in previous years and with a steeper increase of locally-acquired human infections. Between 2014 and 2017, European Union/European Economic Area (EU/EEA) and EU enlargement countries notified five to 25 cases in weeks 25 to 31 compared with 168 cases in 2018. Clinicians and public health authorities should be alerted to ensure timely implementation of prevention measures including blood safety measures.

Partnered pharmacist charting on admission in the General Medical and Emergency Short-stay Unit - a cluster-randomised controlled trial in patients with complex medication regimens.

WHAT IS KNOWN AND OBJECTIVE: Patients admitted to general medical units and emergency short-stay units are often complex with multiple comorbidities, polypharmacy and at risk for drug-related problems associated with increased morbidity and mortality. The aim of this study was to evaluate the effectiveness of a partnered pharmacist charting model completed at the time of admission to prevent medication errors. METHODS: We conducted an unblinded cluster randomized controlled trial comparing partnered pharmacist charting to standard medical charting among patients admitted to general medical units and emergency short-stay units with complex medication regimens or polypharmacy. This trial was conducted at an adult major referral hospital in metropolitan Melbourne, Australia, with an annual emergency department attendance of approximately 60 000 patients. The evaluation included patients' medication charts written in the period of 16 March 2015 to 27 July 2015. Patients randomized to the intervention were managed using the partnered pharmacist charting model. The primary outcome variable was a medication error identified by an independent assessor within 24 h of admission, who was not part of the patient's admission process. RESULTS: Of the 473 patients who received standard medical staff charting during the study period, 372 (78·7%) had at least one medication error identified compared to 15 patients (3·7%) on the partnered pharmacist charting arm (P < 0·001). The relative risk of an error with standard medical charting was 21·4 (95% CI: 13·0-35·0) with a number needed to treat (NNT) to prevent one error of 1·3 (95% CI: 1·3-1·4), and the relative risk of a high or extreme risk error with standard medical charting was 150·9 (95% CI: 21·2-1072·9) with a NNT to prevent one high or extreme error of 2·7 (95% CI 2·4-3·1). WHAT IS NEW AND CONCLUSION: Partnering between medical staff and pharmacists to jointly chart initial medications on admission significantly reduced inpatient medication errors (including errors of high and extreme risk) among general medical and emergency short-stay patients with complex medication regimens or polypharmacy.

Elucidating the clinical characteristics of patients captured using different definitions of massive transfusion.

BACKGROUND AND OBJECTIVES: The type and clinical characteristics of patients identified with commonly used definitions of massive transfusion (MT) are largely unknown. The objective of this study was to define the clinical characteristics of patients meeting different definitions of MT for the purpose of patient recruitment in observational studies. MATERIALS AND METHODS: Data were extracted on all patients who received red blood cell (RBC) transfusions in 2010 at three tertiary Australian hospitals. MT patients were identified according to three definitions: ≥10 units RBC in 24 h (10/24 h), ≥6 units RBC in 6 h (6/6 h) and ≥5 units RBC in 4 h (5/4 h). Clinical coding data were used to assign bleeding context. Data on in-hospital mortality were also extracted. RESULTS: Five hundred and forty-two patients met at least one MT definition, with 236 (44%) included by all definitions. The most inclusive definition was 5/4 h (508 patients, 94%) followed by 6/6 h (455 patients, 84%) and 10/24 h (251 patients, 46%). Importantly, 40-55% of most types of critical bleeding events and 82% of all obstetric haemorrhage cases were excluded by the 10/24 h definition. Patients who met both the 5/4 h and 10/24 h definitions were transfused more RBCs (19 vs. 8 median total RBC units; P < 0·001), had longer ventilation time (120 vs. 55 h; P < 0·001), median ICU (149 vs. 99 h; P < 0·001) and hospital length of stay (23 vs. 18 h; P = 0·006) and had a higher in-hospital mortality rate (23·3% vs. 16·4%; P = 0·050). CONCLUSION: The 5/4 h MT definition was the most inclusive, but combination with the 10/24 h definition appeared to identify a clinically important patient cohort.

Triaging the right patient to the right place in the shortest time.

Trauma systems have been successful in saving lives and preventing disability. Making sure that the right patient gets the right treatment in the shortest possible time is integral to this success. Most trauma systems have not fully developed trauma triage to optimize outcomes. For trauma triage to be effective, there must be a well-developed pre-hospital system with an efficient dispatch system and adequately resourced ambulance system. Hospitals must have clear designations of the level of service provided and agreed protocols for reception of patients. The response within the hospital must be targeted to ensure the sickest patients get an immediate response. To enable the most appropriate response to trauma patients across the system, a well-developed monitoring programme must be in place to ensure constant refinement of the clinical response. This article gives a brief overview of the current approach to triaging trauma from time of dispatch to definitive treatment.

Chicken domestication: an updated perspective based on mitochondrial genomes.

Domestic chickens (Gallus gallus domesticus) fulfill various roles ranging from food and entertainment to religion and ornamentation. To survey its genetic diversity and trace the history of domestication, we investigated a total of 4938 mitochondrial DNA (mtDNA) fragments including 2843 previously published and 2095 de novo units from 2044 domestic chickens and 51 red junglefowl (Gallus gallus). To obtain the highest possible level of molecular resolution, 50 representative samples were further selected for total mtDNA genome sequencing. A fine-gained mtDNA phylogeny was investigated by defining haplogroups A-I and W-Z. Common haplogroups A-G were shared by domestic chickens and red junglefowl. Rare haplogroups H-I and W-Z were specific to domestic chickens and red junglefowl, respectively. We re-evaluated the global mtDNA profiles of chickens. The geographic distribution for each of major haplogroups was examined. Our results revealed new complexities of history in chicken domestication because in the phylogeny lineages from the red junglefowl were mingled with those of the domestic chickens. Several local domestication events in South Asia, Southwest China and Southeast Asia were identified. The assessment of chicken mtDNA data also facilitated our understanding about the Austronesian settlement in the Pacific.

Quantitative microscopy approach for shape-based erythrocytes characterization in anaemia.

Anaemia is one of the most common diseases in the world population. Primarily anaemia is identified based on haemoglobin level; and then microscopically examination of peripheral blood smear is required for characterizing and confirmation of anaemic stages. In conventional approach, experts visually characterize abnormality present in the erythrocytes under light microscope, and this evaluation process is subjective in nature and error prone. In this study, we have proposed a methodology using machine learning techniques for characterizing erythrocytes in anaemia associated with anaemia using microscopic images of peripheral blood smears. First, peripheral blood smear images are preprocessed based on grey world assumption technique and geometric mean filter for reducing unevenness of background illumination and noise reduction. Then erythrocyte cells are segmented using marker-controlled watershed segmentation technique. The erythrocytes in anaemia, such as, tear drop, echinocyte, acanthocyte, elliptocyte, sickle cells and normal erythrocytes cells have been characterized and classified based on their morphological changes. Optimal subset of features, ranked by information gain measure provides highest classification performance using logistic regression classifier in comparison with other standard classifiers.

Predicting massive blood transfusion using clinical scores post-trauma.

BACKGROUND AND OBJECTIVES: Early prediction of massive transfusion (MT) post-trauma may reduce mortality by earlier delivery of blood products. A clinical prediction tool (PWH score) for this purpose was developed at the Prince of Wales Hospital, Hong Kong. The aims of this study were to apply this tool to major trauma patients in Victoria, Australia and compare the score to the Assessment of Blood Consumption (ABC) score and the Trauma-Associated Severe Haemorrhage (TASH) score. METHODS: A retrospective review of patients entered into the The Alfred Trauma Registry between January 2006 and December 2009 was conducted. The performance of the PWH score to predict MT defined by 5 units of packed red blood cells in 4 h was compared with the ABC and TASH scores. Included patients presented to the Emergency & Trauma Centre from the scene and had had complete datasets with respect to the components of the three scores. RESULTS: There were 1234 patients included in the study with 195 (15·8%) receiving a MT and an overall mortality of 14·0%. The PWH score had an area under the receiver operating characteristics (ROC) curve of 0·842 (95% CI: 0·820-0·862). The area under the ROC curve of the PWH score was significantly less than that of the TASH score (χ(2)=19·8, P<0·001) and significantly greater than that of the ABC score (χ(2)=9·3, P=0·002). CONCLUSIONS: The PWH score performs with similar accuracy when applied to an Australian population as in its derivation population. The relative simplicity of the PWH score makes it a viable tool for clinical use, although utility of such tools may be more suited for research in determining inclusion or exclusion criteria for comparative outcome studies.

The association between time to disposition plan in the emergency department and in-hospital mortality of general medical patients.

BACKGROUND: A perceived risk of time-limited emergency department (ED) assessment of patients is inadequate workup leading to inappropriate disposition. The aim of this study was to examine the association of time to disposition plan (TDP) on ED length of stay (LOS) and correlate this to mortality. METHODS: A retrospective review of data collected from ED information systems at three hospitals was conducted between June 2008 and October 2009. Included patients were admitted to a general medical unit. Patients were excluded if admitted to intensive care, coronary care, a cardiac monitored bed or required surgery in first 24 h or had an expected LOS of <48 h. Multivariate regression analysis was used to identify independent associations with mortality. RESULTS: A total of 10,107 patient episodes was analysed, of which 6768 patients (67.0%) had an ED LOS of ≥8 h. There was significant effect modification by ED LOS in the association of TDP and mortality. In the setting of longer ED LOS, a TDP of <4 h was associated with significantly higher mortality (OR 1.57, 95% CI: 1.28-1.92, P < 0.001), corrected for age, gender and triage category. This association was not significant when ED LOS was <8 h (OR 0.88, 95% CI: 0.60-1.27, P = 0.49). CONCLUSIONS: In the setting of prolonged ED LOS, completing ED assessment and management within 4 h of presentation was associated with significantly higher mortality. Further prospective studies are required to understand the relationship between rapid decision making in the ED and patient safety.

Ultrastructural, immunofluorescence, and RNA evidence support the hypothesis of a "new" virus associated with Kawasaki disease.

BACKGROUND: Intracytoplasmic inclusion bodies (ICI) have been identified in ciliated bronchial epithelium of Kawasaki disease (KD) patients using a synthetic antibody derived from acute KD arterial IgA plasma cells; ICI may derive from the KD etiologic agent. METHODS: Acute KD bronchial epithelium was subjected to immunofluorescence for ICI and cytokeratin, high-throughput sequencing, and transmission electron microscopy (TEM). Interferon pathway gene expression profiling was performed on KD lung. RESULTS: An intermediate filament cytokeratin "cage" was not observed around KD ICI, making it unlikely that ICI are overproduced or misfolded human protein aggregates. Many interferon-stimulated genes were detected in the bronchial epithelium, and significant modulation of the interferon response pathway was observed in the lung tissue of KD patients. No known virus was identified by sequencing. Aggregates of virus-like particles (VLP) were detected by TEM in all 3 acute KD patients from whom nonembedded formalin-fixed lung tissue was available. CONCLUSIONS: KD ICI are most likely virus induced; bronchial cells with ICI contain VLP that share morphologic features among several different RNA viral families. Expedited autopsies and tissue fixation from acute KD fatalities are urgently needed to more clearly ascertain the VLP. These findings are compatible with the hypothesis that the infectious etiologic agent of KD may be a "new" RNA virus.

Haemodynamics as a determinant of need for pre-hospital application of a pelvic circumferential compression device in adult trauma patients.

INTRODUCTION: Pelvic ring fractures are common following high-energy blunt trauma and can lead to substantial haemorrhage, morbidity and mortality. Pelvic circumferential compression devices (PCCDs) improve position and stability of open-book type pelvic fracture, and can improve haemodynamics in patients with hypovolaemic shock. However, PCCDs may cause adverse outcomes including worsening of lateral compression fracture patterns and routine use is associated with high costs. Controversy regarding indication of PCCDs exists with some centres recommending PCCD in the setting of hypovolaemic shock compared to placement for any suspected pelvic injury. OBJECTIVE: To assess the need for PCCD application based on pre-hospital vital signs and mechanism of injury. METHODS: A retrospective cohort study was conducted in a single adult major trauma centre examining a 2-year period. Patients were sub-grouped based on initial pre-hospital and emergency department observations as haemodynamically normal (heart rate <100 bpm, systolic blood pressure ≥100 mmHg and Glasgow Coma Scale ≥13) or abnormal. Diagnostic accuracy of pre-hospital haemodynamics as a predictor of pelvic fracture requiring intervention within 24 h was assessed. RESULTS: There were 376 patients with PCCD in-situ on hospital arrival. Pelvic fractures were diagnosed in 137 patients (36.4%). Of these, 39 (28.5%) were haemodynamically normal and 98 (71.5%) were haemodynamically abnormal. The most common mechanisms of injury were motor vehicle collision (57.7%) and motorcycle collision (13.8%). Of those with fractures, 40 patients (29.2%) required pelvic intervention within 24 h of admission; of these, 8 (20%) were haemodynamically normal and 32 (80%) were haemodynamically abnormal. As a test for pelvic fracture requiring intervention within 24 h, abnormal pre-hospital haemodynamics had a sensitivity of 0.80 (95% CI 0.64-0.91), specificity of 0.32 (95% CI 0.27-0.38) and negative predictive value (NPV) of 0.93 (95% CI 0.88-0.96). Combined with absence of a major mechanism of injury, normal haemodynamics had a sensitivity 1.00, specificity 0.51 (95% CI 0.36-0.66) and NPV of 1.00 for pelvic intervention within 24 h. CONCLUSION: Normal haemodynamic status, combined with absence of major mechanism of injury can rule out requirement for urgent pelvic intervention. Ongoing surveillance is recommended to monitor for any adverse effects of this change in practice.

Exploring microdischarges for portable sensing applications.

This paper describes the use of microdischarges as transducing elements in sensors and detectors. Chemical and physical sensing of gases, chemical sensing of liquids, and radiation detection are described. These applications are explored from the perspective of their use in portable microsystems, with emphasis on compactness, power consumption, the ability to operate at or near atmospheric pressure (to reduce pumping challenges), and the ability to operate in an air ambient (to reduce the need for reservoirs of carrier gases). Manufacturing methods and performance results are described for selected examples.

Diel-scale variation of dissolved inorganic carbon during a rainfall event in a small karst stream in southern China.

Metabolic processes of the submerged aquatic community (photosynthesis and respiration) play important roles in regulating diel cycles of dissolved inorganic carbon (DIC) and sequestering carbon in a karst stream. However, little is known of whether diel DIC cycling occurs during rainfall in a karst groundwater-fed stream, even though this question is critical for the accurate estimation of what may be a major terrestrial carbon sink. Here, we measured diel variations of water chemical composition in a small karst groundwater-fed stream in southwest China during a rainfall event to assess the influences of rainfall and rising discharge on DIC diel cycling and the potential carbon sink produced by in-stream metabolism. Our results show that water chemical composition at the source spring (CK site) is relatively stable due to chemostatic behavior during rising discharge after a rainfall period. This site lacked submerged aquatic vegetation and, thus, had no diel variations in water chemistry. However, diel cycles of all hydrochemical parameters occurred at a site 1.3 km downstream (LY site). Diel variations in pH, DO, and δ13CDIC were inversely related to diel changes in SpC, DIC, Ca2+, and pCO2. These results indicated that diel cycling of DIC due to in-stream metabolism of submerged aquatic community was still occurring during elevated discharge from rainfall. We estimate the carbon sink through the in-stream metabolism of the submerged aquatic community to be 5.6 kg C/day during the studied rainfall event. These results imply that submerged aquatic communities in a karst stream can significantly stabilize carbon originating from the carbonate rock weathering processes in karst areas.

Video-tube thoracostomy in trauma resuscitation: A pilot study.

BACKGROUND: Complications related to incorrect positioning of tube thoracostomy (TT) have been reported to be as high as 30%. The aim of this study was to assess the feasibility of flexible videoscope guided placement of a pre-loaded chest tube, permitting direct intrapleural visualization and placement (Video-Tube Thoracostomy [V-TT]). METHODS: A prospective, single centre, phase 1 pilot study with a parallel control group was undertaken. The population studied were adult thoracic trauma patients requiring emergency TT who were haemodynamically stable. The intervention performed was VTT. Patients in the control group underwent conventional TT. The primary outcome was tube position as defined by a consultant radiologist's interpretation of chest x-ray (CXR) or CT. The trial was registered with ANZCTR.org.au (ACTRN: 12,615,000,870,550). RESULTS: There were 37 patients enrolled in the study - 12 patients allocated to the VTT intervention group and 25 patients allocated to conventional TT. Mean age of participants was 48 years (SD 15) in intervention group and 46 years (SD 15) years in the control group. In the VTT group all patients were male; the indications were pneumothorax (83%), haemothorax (8%) and haemopneumothorax (8%). The median injury severity score was 23 (16-28). There were 1 positional and 1 insertional complications. In the control group 72% of patients were male, the indications were pneumothorax (56%), haemothorax (4%) and haemopneumothorax (40%). The median injury severity score was 24 (14-36). There were 8 (32%) positional complications and no insertional complications. CONCLUSION: V-TT was demonstrated to be a feasible alternative to conventional thoracostomy and merits further investigation.

A checklist for trauma quality improvement meetings: A process improvement study.

BACKGROUND: Each year approximately five million people die from injuries. In countries where systems of trauma care have been introduced, death and disability have decreased. A major component of developed trauma systems is a trauma quality improvement (TQI) program and trauma quality improvement meeting (TQIM). Effective TQIMs improve trauma care by identifying and fixing problems. But globally, TQIMs are absent or unstructured in most hospitals providing trauma care. The aim of this study was to implement and evaluate a checklist for a structured TQIM. METHODS: This project was conducted as a prospective before-and-after study in four major trauma centres in India. The intervention was the introduction of a structured TQIM using a checklist, introduced with a workshop. This workshop was based on the World Health Organization (WHO) TQI Programs short course and resources, plus the developed TQIM checklist. Pre- and post-intervention data collection occurred at all meetings in which cases of trauma death were discussed. The primary outcome was TQIM Checklist compliance, defined by the discussion of, and agreement upon each of the following: preventability of death, identification of opportunities to improve care and corrective actions and a plan for closing the loop. RESULTS: There were 34 meetings in each phase, with 99 cases brought to the pre-intervention phase and 125 cases brought to the post-intervention phase. There was an increase in the proportion of cases brought to the meeting for which preventability of death was discussed (from 94% to 100%, p = 0.007) and agreed (from 7 to 19%, OR 3.7; 95% CI:1.4-9.4, p = 0.004) and for which a plan for closing the loop was discussed (from 2% to 18%, OR 10.9; 95% CI:2.5-47.6, p < 0.001) and agreed (from 2% to 18%, OR 10.9; 95% CI:2.5-47.6, p < 0.001). CONCLUSION: This study developed, implemented and evaluated a TQIM Checklist for improving TQIM processes. The introduction of a TQIM Checklist, with training, into four Indian trauma centres, led to more structured TQIMs, including increased discussion and agreement on preventability of death and plans for loop closure. A TQIM Checklist should be considered for all centres managing trauma patients.

An epidemic of illicit fentanyl deaths in Cook County, Illinois: September 2005 through April 2007.

Between September 2005 and April 2007, 350 fentanyl intoxication deaths were investigated and certified by the Cook County Medical Examiners Office. Investigations revealed that the majority of these fatalities were by intravenous injection of a white powder followed by a rapid collapse. The fentanyl was clandestinely produced in a lab in Toluca, Mexico and sold by the Mickey Cobra street gang. The term "Drop Dead" was coined for this "tainted heroin." Postmortem samples were screened by ELISA and confirmed by standard GC-MS methods. Fentanyl fatalities peaked at 47 per month in May and June 2006. Fifty-two percent were single fentanyl intoxications, with the remainder accompanied by either cocaine, morphine from heroin, or alcohol. This epidemic stressed the limited resources of the toxicology laboratory and autopsy service of the Medical Examiners Office. The clandestine lab was terminated, distributing gang members and leaders arrested, and the epidemic ceased in April 2007.

A novel approach to improving the interpretation of CT brain in trauma.

BACKGROUND: Computed tomography of the brain (CTB) has a fundamental role in the diagnosis and management of traumatic brain injury (TBI). There may be substantial discordance between initial CTB interpretation by emergency clinicians and the final radiology report. This study aimed to assess the utility of a structured reporting template in improving the accuracy of CTB interpretation by emergency clinicians. METHOD: A prospective pre- and post-intervention cohort study was undertaken using a study population of emergency medicine trainees. The CTB reporting template was created with consultation from radiology, emergency medicine and trauma specialists. Participants reported on a set of randomly selected trauma CTBs first without, and then with, the reporting template. Each case was independently assessed for concordance with the radiology report by two blinded assessors (including a radiologist) and the proportion of concordant reports in each phase calculated. RESULTS: There were 26 participants recruited to the study who reported on a total of 320 CTBs. In the pre-intervention phase, 121 (76%) cases were concordant with the radiology report compared to 147 (92%) post-intervention (p<0.01). The AUROC was 0.84 (95% CI: 0.78-0.89) pre-intervention and improved to 0.94 (95% CI: 0.88-0.99) with the intervention (p=0.01). A higher level of baseline accuracy was observed in advanced trainees (78%) compared to basic trainees (72%), but both improved to a similar level of 92% with the use of the CTB reporting template. There was a marked reduction in false negative errors, with increased identification of critical diagnoses such as cerebral herniation and diffuse axonal injury. CONCLUSION: The use of the CTB reporting template significantly increased the accuracy of emergency medicine trainees and reduced the number of missed critical diagnoses. Reporting templates may represent an effective strategy to improve CTB interpretation and enhance the initial care of head injured patients.

Structure of the monotopic membrane protein (S)-mandelate dehydrogenase at 2.2 Šresolution.

The x-ray structure of the monotopic membrane protein (S)-mandelate dehydrogenase (MDH) from Pseudomonas putida reveals an inherent flexibility of its membrane binding segment that might be important for its biological activity. The surface of MDH exhibits a concentration of the positive charges on one side and the negative charges on the other side. The putative membrane binding surface of MDH has a concentric circular ridge, formed by positively charged residues, which projects away from the protein surface by ∼4 Å; this is an unique structural feature and not observed in other monotopic membrane proteins to our knowledge. There are three α-helixes in the membrane binding region. Based on the structure of MDH, it is possible to propose that the interaction of MDH with the membrane is stabilized by coplanar electrostatic interactions, between the positively charged concentric circular ridge and the negatively charged head-groups of the phospholipid bilayer, along with three α-helixes that provide additional stability by inserting into the membrane. The structure reveals the possible orientation of these helixes along with possible roles for the individual residues which form those helixes. These α-helixes may play a role in the enzyme's mobility. A detergent molecule, N-Dodecyl-ß-maltoside, is inserted between the membrane binding region and rest of the molecule and may provide structural stability to intra-protein regions by forming hydrogen bonds and close contacts. From the average B-factor of the MDH structure, it is likely that MDH is highly mobile, which might be essential for its interaction in membrane and non-membrane environments, as its substrate (S)-mandelate, is from the cytoplasm, while its electron acceptor is a component of the membrane electron transport chain.

Descending thoracic aortic aneurysm presenting as left sided hemorrhagic pleural effusion.

Aneurysm of descending thoracic aorta, in majority of cases is diagnosed either by chance in routine chest imaging for some other reasons or rarely due to it's symptomatic presentation like chest pain and other mediastinal compression symptoms. In this case report we present a case of 69 year old smoker who presented with cough, hemoptysis and left sided massive painless hemorrhagic pleural effusion. Further investigation revealed a large aneurysm of descending thoracic aorta which infiltrated the left lung. We suggest descending thoracic aneurysm be included in the differential diagnosis of this sort of clinical presentation which otherwise imperative with the clinical scenario of bronchogenic carcinoma.

In-stream metabolism and atmospheric carbon sequestration in a groundwater-fed karst stream.

Atmospheric carbon sequestered in karst systems through dissolution of carbonate minerals is considered to have no net effect on long-term regional and global carbon budgets because precipitation of dissolved carbonate minerals emits CO2 back to the atmosphere. Even though recent studies have implied that rapid kinetics of carbonate dissolution coupled with the aquatic photosynthetic uptake of dissolve inorganic carbon (DIC) could facilitate a stable atmospheric C sink in karst rivers and streams, little is known about the magnitudes and long-term stability of this C sink. To assess in-stream biogeochemical processes and their role on stream C cycling, we measured diel cycles of water characteristics and chemical composition (temperature, pH, DO, SpC, DIC, Ca2+, δ13CDIC) in a groundwater-fed karst stream in southwest China. Our results show no diel variations at the groundwater discharge point (CK site) due to the absence of a sub-aquatic community (SAC). However, all hydrochemical parameters show significant diel cycle 1.3km downstream (LY site). Diel variations in pH, DO, and δ13CDIC were inversely related to diel changes in SpC, DIC, Ca2+ and pCO2. This result indicates that in-stream metabolism (photosynthesis and respiration) of SAC controls diel variations in stream water chemistry. Significant diel cycles of net ecosystem production (NEP) influences in-stream diel fluctuation of pH, DO, SIc, DIC, pCO2, Ca2+ and δ13CDIC, with gross primary production (GPP) dominating in day and ecosystem respiration (ER) dominating at the night. Absence of in-stream metabolism at CK enhances CO2 degassing from stream to the atmosphere, which is estimated to be 3-5 times higher than at LY. We estimate the carbon sink through in-stream metabolism of SAC to be 73tCkm-2a-1, which is around half the rate of the oceanic biological pump. These results imply in-stream photosynthesis sequesters DIC originating from karst weathering and controls CO2 evasion.