Using dynamic modelling to enhance the assessment of the beef water footprint

Current water footprint assessment methods make a meaningful assessment of livestock water consumption difficult as they are mainly static, thus poorly adaptable to understanding future water consumption and requirements. They lack the integration of fundamental ruminant nutrition and growth equations within a dynamic context that accounts for short- and long-term behaviour and time delays associated with economically significant beef-producing areas. The current study utilised the System Dynamics methodology to conceptualise a water footprint for beef cattle within a dynamic and mechanistic modelling framework. The problem of assessing the water footprint of beef cattle was articulated, and a dynamic hypothesis was formed to represent the Texas livestock water use system as the initial step in developing the Dynamic Beef Water Footprint model (DWFB). The dynamic hypothesis development resulted in three causal loop diagrams (CLD): cattle population, growth and nutrition, and the livestock water footprint, that captured the daily water footprint of beef (WFB). Simulations and sensitivity analysis from the hypothesised CLD structures indicated that the framework was able to capture the dynamic behaviour of the WFB system. These behaviours included key reinforcing and balancing feedback processes that drive the WFB. It is extremely difficult to identify policy interventions (i.e., management strategies) for complex systems, like the U.S. beef cattle system, because there are many actors (i.e., cow-calf, stocker, feedlot) and interrelated variables that have delayed effects within and across the supply chain. Identification and understanding of feedback processes driving water use over time will help to overcome policy resistance for more sustainable beef production. Thus, the causal loops identified in the current study provide a system-level insight for the drivers of the WFB within and across each major segment of the beef supply chain to address freshwater concerns more adequately. Further, the nutrient scenarios and sensitivity analysis revealed that the high versus low nutrient composition of pasture, hay, and concentrates resulted in a significant difference in the WFB (2 669 L/kg boneless beef, P < 0.05). The WFB was sensitive to changes in nutrient composition and specific water demand (m3/t) for each production phase, not only phases with high levels of concentrate feed use. As models evolve, there is potential for the DWFB to integrate precision livestock data, further improving quantification of the WFB, precision water-efficient strategies, and selection of water-efficient livestock.

Association of Sex and Age With Mild Traumatic Brain Injury-Related Symptoms: A TRACK-TBI Study

IMPORTANCE

Knowledge of differences in mild traumatic brain injury (mTBI) recovery by sex and age may inform individualized treatment of these patients.

OBJECTIVE

To identify sex-related differences in symptom recovery from mTBI; secondarily, to explore age differences within women, who demonstrate poorer outcomes after TBI.

DESIGN, SETTING, AND PARTICIPANTS

The prospective cohort study Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) recruited 2000 patients with mTBI from February 26, 2014, to July 3, 2018, and 299 patients with orthopedic trauma (who served as controls) from January 26, 2016, to July 27, 2018. Patients were recruited from 18 level I trauma centers and followed up for 12 months. Data were analyzed from August 19, 2020, to March 3, 2021.

EXPOSURES

Patients with mTBI (defined by a Glasgow Coma Scale score of 13-15) triaged to head computed tomography in 24 hours or less; patients with orthopedic trauma served as controls.

MAIN OUTCOMES AND MEASURES

Measured outcomes included (1) the Rivermead Post Concussion Symptoms Questionnaire (RPQ), a 16-item self-report scale that assesses postconcussion symptom severity over the past 7 days relative to preinjury; (2) the Posttraumatic Stress Disorder Checklist for the Diagnostic and Statistical Manual of Mental Disorders (Fifth Edition) (PCL-5), a 20-item test that measures the severity of posttraumatic stress disorder symptoms; (3) the Patient Health Questionnaire-9 (PHQ-9), a 9-item scale that measures depression based on symptom frequency over the past 2 weeks; and (4) the Brief Symptom Inventory-18 (BSI-18), an 18-item scale of psychological distress (split into Depression and Anxiety subscales).

RESULTS

A total of 2000 patients with mTBI (1331 men [67%; mean (SD) age, 41.0 (17.3) years; 1026 White (78%)] and 669 women [33%; mean (SD) age, 43.0 (18.5) years; 505 (76%) White]). After adjustment of multiple comparisons, significant TBI × sex interactions were observed for cognitive symptoms (B = 0.76; 5% false discovery rate-corrected P = .02) and somatic RPQ symptoms (B = 0.80; 5% false discovery rate-corrected P = .02), with worse symptoms in women with mTBI than men, but no sex difference in symptoms in control patients with orthopedic trauma. Within the female patients evaluated, there was a significant TBI × age interaction for somatic RPQ symptoms, which were worse in female patients with mTBI aged 35 to 49 years compared with those aged 17 to 34 years (B = 1.65; P = .02) or older than 50 years (B = 1.66; P = .02).

CONCLUSIONS AND RELEVANCE

This study found that women were more vulnerable than men to persistent mTBI-related cognitive and somatic symptoms, whereas no sex difference in symptom burden was seen after orthopedic injury. Postconcussion symptoms were also worse in women aged 35 to 49 years than in younger and older women, but further investigation is needed to corroborate these findings and to identify the mechanisms involved. Results suggest that individualized clinical management of mTBI should consider sex and age, as some women are especially predisposed to chronic postconcussion symptoms even 12 months after injury.

A Systematic Review of Clinical Practice Guidelines for Identification and Management of Frailty

OBJECTIVE

This study aims to appraise and summarize consistent recommendations from clinical practice guidelines (CPGs) for identification and management of frailty to maintain and improve functional independence of elderly population.

METHODS

A systematic search of Ovid MEDLINE, Embase, PubMed, PsycINFO, and CINAHL electronic databases using database-specific search terms in two broad areas "guidelines" and "frailty", and a manual search of websites with the key phrase "frailty guideline" was performed. The inclusion criteria included CPGs focusing on identifying and managing frailty in population >65 years old, published in English since January 2010. Three reviewers independently assessed guideline quality using the AGREE II instrument. Data extraction was performed, followed by compilation and comparison of all recommendations to identify the key consistent recommendations.

RESULTS

Six CPGs met the inclusion criteria; however, only three CPGs had high methodological quality in accordance with AGREE II appraisal. The average AGREE II scores of all six CPGs were: 84.5%, 68%, 46.5%, 81.5%, 56.3%, and 60.2% for domains 1-6 (scope and purpose, stakeholder involvement, rigour of development, clarity of presentation, applicability, and editorial independence) respectively. A total of 54 recommendations were identified, with 12 key recommendations suggested frequently by the CPGs.

CONCLUSION

The AGREE II instrument identified strengths and weaknesses of the CPGs, but failed to assess clinical implications and feasibility of the guidelines. Further research is needed to improve clinical relevance of CPGs in the identification and management of frailty. The feasibility in implementing these guidelines with regards to cost-effectiveness of frailty screening warrants further investigation.

Early versus Late Profiles of Inflammatory Cytokines after Mild Traumatic Brain Injury and Their Association with Neuropsychological Outcomes

Despite pre-clinical evidence for the role of inflammation in traumatic brain injury (TBI), there is limited data on inflammatory biomarkers in mild TBI (mTBI). In this study, we describe the profile of plasma inflammatory cytokines and explore associations between these cytokines and neuropsychological outcomes after mTBI. Patients with mTBI with negative computed tomography and orthopedic injury (OI) controls without mTBI were prospectively recruited from emergency rooms at three trauma centers. Plasma inflammatory cytokine levels were measured from venous whole-blood samples that were collected at enrollment (within 24 h of injury) and at 6 months after injury. Neuropsychological tests were performed at 1 week, 1 month, 3 months, and 6 months after the injury. Multivariate regression analysis was performed to identify associations between inflammatory cytokines and neuropsychological outcomes. A total of 53 mTBI and 24 OI controls were included in this study. The majority of patients were male (62.3%), and injured in motor vehicle accidents (37.7%). Plasma interleukin (IL)-2 (p = 0.01) and IL-6 (p = 0.01) within 24 h post-injury were significantly higher for mTBI patients compared with OI controls. Elevated plasma IL-2 at 24 h was associated with more severe 1-week post-concussive symptoms (p = 0.001). At 6 months, elevated plasma IL-10 was associated with greater depression scores (p = 0.004) and more severe post-traumatic stress disorder (PTSD) symptoms (p = 0.001). Plasma cytokine levels (within 24 h and at 6 months post-injury) were significantly associated with early and late post-concussive symptoms, PTSD, and depression scores after mTBI. These results highlight the potential role of inflammation in the pathophysiology of post-traumatic symptoms after mTBI.

Predictors and Prevalence of Nodal Disease in Salvage Oropharyngectomy

BACKGROUND

Patients with recurrent oropharyngeal cancer often require extensive salvage surgery. For patients with clinically N0 necks, the indication for concurrent neck dissection remains unclear. This study aimed to determine predictors, prevalence, and distribution of nodal disease in patients treated with salvage oropharyngectomy.

METHODS

In a case series with data collection at a single tertiary academic National Cancer Institute (NCI)-designated comprehensive cancer center, this study analyzed patients treated with prior radiation or chemoradiation who had persistent, recurrent, or second primary squamous cell carcinoma of the oropharynx requiring oropharyngeal resection between 1998 and 2017 (n = 95). Clinical and oncologic characteristics and treatment outcomes were collected, and statistical analyses were performed.

RESULTS

The overall rate of nodal positivity was 21% (24/95), and the rate of occult nodal disease was 6% (4/65). Ipsilateral and contralateral level 2 were the most common areas harboring positive nodes. Bivariate analysis showed female sex (p = 0.01), initial overall stage (p = 0.02), and N status (p = 0.03), as well as recurrent overall and T stage (p = 0.05) to be predictors of nodal disease. In the multivariate analysis, recurrent T stage continued to be significantly predictive of pathologic nodal disease. Both computed tomography (CT) and positron emission tomography-CT were moderately accurate in predicting nodal disease in the salvage setting (area under the curve, 0.79 and 0.80, respectively).

CONCLUSION

Occult nodal disease is observed in few patients undergoing salvage oropharyngeal resection. This study identified factors predictive of nodal disease in patients undergoing salvage oropharyngectomy and appropriate diagnostic tests in this setting.

Identical and Nonidentical Twins: Risk and Factors Involved in Development of Islet Autoimmunity and Type 1 Diabetes

OBJECTIVE

There are variable reports of risk of concordance for progression to islet autoantibodies and type 1 diabetes in identical twins after one twin is diagnosed. We examined development of positive autoantibodies and type 1 diabetes and the effects of genetic factors and common environment on autoantibody positivity in identical twins, nonidentical twins, and full siblings.

RESEARCH DESIGN AND METHODS

Subjects from the TrialNet Pathway to Prevention Study (N = 48,026) were screened from 2004 to 2015 for islet autoantibodies (GAD antibody [GADA], insulinoma-associated antigen 2 [IA-2A], and autoantibodies against insulin [IAA]). Of these subjects, 17,226 (157 identical twins, 283 nonidentical twins, and 16,786 full siblings) were followed for autoantibody positivity or type 1 diabetes for a median of 2.1 years.

RESULTS

At screening, identical twins were more likely to have positive GADA, IA-2A, and IAA than nonidentical twins or full siblings (all P < 0.0001). Younger age, male sex, and genetic factors were significant factors for expression of IA-2A, IAA, one or more positive autoantibodies, and two or more positive autoantibodies (all P ≤ 0.03). Initially autoantibody-positive identical twins had a 69% risk of diabetes by 3 years compared with 1.5% for initially autoantibody-negative identical twins. In nonidentical twins, type 1 diabetes risk by 3 years was 72% for initially multiple autoantibody-positive, 13% for single autoantibody-positive, and 0% for initially autoantibody-negative nonidentical twins. Full siblings had a 3-year type 1 diabetes risk of 47% for multiple autoantibody-positive, 12% for single autoantibody-positive, and 0.5% for initially autoantibody-negative subjects.

CONCLUSIONS

Risk of type 1 diabetes at 3 years is high for initially multiple and single autoantibody-positive identical twins and multiple autoantibody-positive nonidentical twins. Genetic predisposition, age, and male sex are significant risk factors for development of positive autoantibodies in twins.

What Really Matters to You? A Study of Public Perspectives on General Practice in Ireland

Aims In recent years it has been recognised that person-centred care can lead to better outcomes for patients and a reduced burden on healthcare systems. The aim of this study was to explore what really matters to members of the public when they visit a GP in Ireland. Methods This qualitative study used a structured interview methodology with one question; “What really matters to you when you go to see a GP?” Results were analysed using an integrated approach, involving both inductive and deductive methods. Results Responses from the 10 study participants were subdivided into two overarching themes: the General Practitioner as a person and the General Practice as a service. Personality (open, approachable, personable, trusted, interested) and service (time, cost, convenience, personal relationship) traits matter to patients. Conclusion Patients must be facilitated and encouraged to voice what really matters to them in order to inform truly person-centred healthcare improvement.

Guidelines To Validate Control of Cross-Contamination during Washing of Fresh-Cut Leafy Vegetables

The U.S. Food and Drug Administration requires food processors to implement and validate processes that will result in significantly minimizing or preventing the occurrence of hazards that are reasonably foreseeable in food production. During production of fresh-cut leafy vegetables, microbial contamination that may be present on the product can spread throughout the production batch when the product is washed, thus increasing the risk of illnesses. The use of antimicrobials in the wash water is a critical step in preventing such water-mediated cross-contamination; however, many factors can affect antimicrobial efficacy in the production of fresh-cut leafy vegetables, and the procedures for validating this key preventive control have not been articulated. Producers may consider three options for validating antimicrobial washing as a preventive control for cross-contamination. Option 1 involves the use of a surrogate for the microbial hazard and the demonstration that cross-contamination is prevented by the antimicrobial wash. Option 2 involves the use of antimicrobial sensors and the demonstration that a critical antimicrobial level is maintained during worst-case operating conditions. Option 3 validates the placement of the sensors in the processing equipment with the demonstration that a critical antimicrobial level is maintained at all locations, regardless of operating conditions. These validation options developed for fresh-cut leafy vegetables may serve as examples for validating processes that prevent cross-contamination during washing of other fresh produce commodities.

Endotension after Endovascular Aneurysm Repair: Definition, Classification, and Strategies for Surveillance and Intervention

In the ongoing evolution of a categorization system for endoleak, the authors propose the term endotension to define persistent or recurrent pressurization of the aortic aneurysm sac after endovascular repair. Endotension is evidence that the aneurysm remains at risk of rupture and should, therefore, be considered an indication for secondary intervention. Management strategies and a grading system for endotension are offered.

Longitudinal Aneurysm Shrinkage following Endovascular Aortic Aneurysm Repair: A Source of Intermediate and Late Complications

Purpose:

To report the incidence of delayed complications following endovascular abdominal aortic aneurysm (AAA) repair and the relationship of these sequelae to morphological changes in the sac and endograft.

Methods:

Twenty-six AAA patients treated with Vanguard endografts had completed ≥1-year follow-up. Postoperative angiograms and spiral computed tomographic (CT) scans with 3-dimensional reconstruction were compared to the 1-year images to determine morphological changes in the aneurysm sac and the endograft. These changes were then related to complications occurring between 1 and 12 months postoperatively in the study group.

Results:

Comparison of angiograms uncovered endograft buckling in 18 (69%) patients and acutely angled or kinked endografts in 10 (38%). Measurements from the CT scans found that undistorted endografts had a mean change in sac length of +6.6 mm. Mean sac length change in buckled endografts was −3.1 mm, while kinked endografts displayed a mean change of −6.2 mm (p < 0.002, Student's t-test). Five (19%) patients, all with distorted endografts, demonstrated late (1 to 12 months) complications (4 endoleaks and 1 graft limb thrombosis) owing to component separation, distal stent migration, and acute angulation. No movement in the proximal stent was observed. Elongation of the endograft (flow line measurement) was observed in one tube graft only.

Conclusions:

In this study, longitudinal shrinkage of the sac following endovascular aortic aneurysm repair led to buckling or kinking of the endograft within 1 year in 69% of patients. This appears to be an important source of delayed complications.

Radical Cystectomy Perioperative Care Redesign

OBJECTIVE

To present an evidence-based review of the perioperative management of the radical cystectomy (RC) patient in the context of a care redesign initiative.

METHODS

A comprehensive review of the key factors associated with perioperative management of the RC patient was completed. PubMed, Medline, and the Cochrane databases were queried via a computerized search. Specific topics were reviewed within the scope of the three major phases of perioperative management: preoperative, intraoperative, and postoperative. Preference was given to evidence from prospective randomized trials, meta-analyses, and systematic reviews.

RESULTS

Preoperative considerations to improve care in the RC patient should include multi-disciplinary medical optimization, patient education, and formal coordination of care. Efforts to mitigate the risk of malnutrition and reduce postoperative gastrointestinal complications may include carbohydrate loading, protein nutrition supplementation, and avoiding bowel preparation. Intraoperatively, a fluid and opioid sparing protocol may reduce fluid shifts and avoid complications from paralytic ileus. Finally, enhanced recovery protocols including novel medications, early feeding, and multi-modal analgesia approaches are associated with earlier postoperative convalescence.

CONCLUSION

RC is a complex and morbid procedure that may benefit from care redesign. Evidence based quality improvement is integral to this process. We hope that this review will help guide further improvement initiatives for RC.

The use of immunosuppressive agents in the management of recalcitrant lower limb ulcers

OBJECTIVE

Lower limb ulcers that are resistant to standard forms of treatment place a significant burden on both patients and health services. There is no widely agreed definition of a recalcitrant ulcer but failure to heal following 6-12 months of focused treatment would identify a small group of patients with highly resistant ulceration. We describe a series of patients with recalcitrant ulceration for which immunosuppressive agents have been used.

METHODS

This is a case series of 13 patients who underwent immunomodulation therapy for lower limb ulcers at a tertiary referral university hospital. Regimens of immunomodulation used mainly ciclosporin and/or cyclophosphamide, with concurrent antibiotic therapy. Case notes and computer systems were analysed by two reviewers. A patient was deemed to have a success if their ulcer fully healed while on immunomodulation therapy.

RESULTS

Over a period of eight years, from 2004-2012, 13 patients underwent immunomodulation therapy. Among these patients there were 18 ulcerated limbs. Ulcer healing occurred in 10 limbs out of 18 (55.6%) and full healing occurred in six patients (46.2%). Ulcers were present for a median of five years (range 2-40 years), with a median diameter of 7.5 cm (range 4-18 cm) before treatment.

CONCLUSION

Treatment of truly recalcitrant ulceration can be very frustrating for both the patient and physician, with poor success from more standard forms of treatment. We report experience with immunomodulation therapy that suggests there may be benefit from using this treatment in a subset of patients with this debilitating disease.

Redefining the golden hour for severe head injury in an urban setting: the effect of prehospital arrival times on patient outcomes

BACKGROUND

In patients with severe head injuries, transportation to a trauma centre within the "golden hour" are important markers of trauma system effectiveness but evidence regarding impacts on patient outcomes is limited.

OBJECTIVE

To determine the effect of patient arrival within the golden hour on patient outcomes.

METHODS

A retrospective cohort of adult patients with severe head injuries (head AIS ≥ 3) arriving within 24h of injury was identified using the trauma registry from 2000 to 2011. Survival analysis was used to determine the effect of patient arrival time on overall mortality. Study outcomes were in hospital mortality and survival to hospital discharge without requiring transfer for ongoing rehabilitation or nursing home care.

RESULTS

There was a significant association with mortality with each incremental minute of patient arrival (HR 1.002, 95%CI 1.001-1.004, p=0.001). There was however no survival benefit observed for patients arriving within 60 min of injury time (HR 0.77, 95%CI 0.50-1.18, p=0.22) but an apparent benefit for those presenting within 2h of injury time (HR 0.31, 95%CI 0.15-0.66, p=0.002). Patient arrival within 60 min of injury time was associated with increased odds of survival to hospital discharge without requiring ongoing rehabilitation (OR 1.78, 95%CI 1.14-2.79, p=0.01).

CONCLUSION

A survival benefit exists in patients arriving earlier to hospital after severe head injury but the benefit may extend beyond the golden hour. There was evidence of improved functional outcomes in patients arriving within 60 min of injury time.

A novel case of laparoscopic ureterolithotomy in a partial duplex ureteric collecting system: can open procedures still be justified in the minimally invasive era?

BACKGROUND

Impacted ureteric stones can pose a treatment challenge due to the high level of failure of ESWL and endourological approaches. Laparoscopic ureterolithotomy can provide a safe and successful alternative to these and open, invasive procedures.

METHODS

Interval laparoscopic ureterolithtomy was carried out following placement of a percutaneous nephrostomy. This was performed through an trans-peritoneal approach with the ureterotomy closed by intracorporeal suturing and placement of a JJ stent without the need for an abdominal wound drain.

CONCLUSION

Laparoscopic ureterolithotomy is a safe, minimally invasive method of managing large, impacted ureteric stones with minimal associated patient morbidity.

Revisiting cerebral thromboangiitis obliterans

We describe a 56-year-old patient with progressive cognitive decline in the context of heavy tobacco use and migraine, and imaging evidence of an occlusive terminal cerebral vasculopathy. The results of brain biopsy recapitulated the pathological features described by Lindenberg and Spatz in their classic 1939 treatise on cerebral thromboangiitis obliterans, or cerebral Buerger's disease. Although the condition is associated with heavy smoking, the identification of a hypercoagulable state in our patient suggests a multifactorial pathogenesis. The diagnosis of cerebral thromboangiitis obliterans in life is facilitated by modern neuroimaging and should prompt immediate cessation of smoking and a search for an underlying prothrombotic tendency.