In vivo determination of human breast fat composition by ¹H magnetic resonance spectroscopy at 7 T.

The role of diet and fat consumption in the pathogenesis of breast cancer is an important subject. We report a method for noninvasive determination of lipid composition in human breast by proton magnetic resonance spectroscopy (MRS) at 7 T. Two respiratory-triggered TE-averaged stimulated echo acquisition mode (STEAM) acquisitions were performed on the adipose tissue of 10 healthy volunteers where the second acquisition had all gradients inverted. This acquisition protocol allows the suppression of modulation sidebands that complicate spectral analysis at the short TE(avg) = 24.5 ms. The entire acquisition takes ∼10 min. Ten lipid peaks were typically resolved. T(1) and T(2) were also measured and used to correct the peak intensities. The calculated average lipid composition for saturated was 28.7 ± 8.4%, monounsaturated, 48.5 ± 7.9%, and polyunsaturated, 22.7 ± 3.1%, in close agreement with reported values from subcutaneous adipose measurements. Intrasubject variability was 2.0, 1.6, and 3.6% for the saturated, monounsaturated, and polyunsaturated fractions, respectively. In conclusion, we have shown that a chemical analysis of lipids in breast tissue can be determined quite simply, quickly, and noninvasively by proton MRS at 7 T.

Using the Postoperative Morbidity Survey to Measure Morbidity After Cranial Neurosurgery.

BACKGROUND: The incidence of morbidity after cranial neurosurgery is significant, reported in up to a quarter of patients depending on methodology used. The Postoperative Morbidity Survey (POMS) is a reliable method for identifying clinically relevant postsurgical morbidity using 9 organ system domains. The primary aim of this study was to quantify early morbidity after cranial neurosurgery using POMS. The secondary aims were to identify non-POMS-defined morbidity and association of POMS with postoperative hospital length of stay (LOS). MATERIALS AND METHODS: A retrospective electronic health care record review was conducted for all patients who underwent elective or expedited major cranial surgery over a 3-month period. Postsurgical morbidity was quantified on postoperative days (D) 1, 3, 5, 8, and 15 using POMS. A Poisson regression model was used to test the correlation between LOS and total POMS scores on D1, 3 and 5. A further regression model was used to test the association of LOS with specific POMS domains. RESULTS: A total of 246 patients were included. POMS-defined morbidity was 40%, 30%, and 33% on D1, D3, and D8, respectively. The presence of POMS morbidity on these days was associated with longer median (range) LOS: D1 6 (1 to 49) versus 4 (2 to 45) days; D3 8 (4 to 89) versus 6 (4 to 35) days; D5 14 (5 to 49) versus 8.5 (6 to 32) days; D8 18 (9 to 49) versus 12.5 (9 to 32) days (P<0.05). Total POMS score correlated with overall LOS on D1 (P<0.001), D3 (P<0.001), and D5 (P<0.001). A positive response to the "infectious" (D1, 3), "pulmonary" (D1), and "renal" POMS items (D1) were associated with longer LOS. CONCLUSION: Although our data suggests that POMS is a useful tool for measuring morbidity after cranial neurosurgery, some important morbidity items that impact on LOS are missed. A neurosurgery specific tool would be of value.

Wellbeing of Frontline Health Care Workers After the First SARS-CoV-2 Pandemic Surge at a Neuroscience Centre: A Cross-sectional Survey.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has affected people of all ages, races, and socioeconomic groups, and placed extraordinary stress on health care workers (HCWs). We measured the prevalence of burnout and assessed wellbeing and quality of life (QoL) in HCWs at a single UK neuroscience center after the first pandemic surge. METHODS: A 38-item electronic questionnaire was disseminated through local team email lists between May 22 and June 7, 2020, to HCWs in a university neurosciences center. Burnout was measured using the single-item Emotional Exhaustion and Depersonalization scales, and wellbeing and QoL assessed using the Linear Analogue Self-Assessment Scale and the EuroQol-5 Dimension instrument. RESULTS: The response rate was 57.4% (n=234); 58.2% of respondents were nurses, 69.4% were women and 40.1% were aged 25 to 34 years. Overall, 21.4% of respondents reported burnout assessed by the Emotional Exhaustion scale; burnout was higher for nurses (23.5%) and allied health care professionals (22.5%) compared with doctors (16.4%). HCWs from ethnic minority groups reported a higher rate of burnout (24.5%) compared with white HCWs (15.0%). There were no differences in reported wellbeing or QoL between professional groups, or HCW age, sex, or race. Nurses (36.8%) and staff from ethnic minority groups (34.6%) were more fearful for their health than others. CONCLUSIONS: Our findings highlight the prevalence of HCW burnout after the first surge of the pandemic, with an increased risk of burnout among nurses and staff from ethnic minority groups. Both nursing and staff from ethnic minority groups were also more fearful for their health. With ongoing pandemic surges, the impact on HCW wellbeing should be continuously assessed to ensure that local strategies to support staff wellbeing are diverse and inclusive.

Outcomes of Laparoscopic Peritoneal Dialysis Catheter Placement Using an Optimal Placement Technique.

BACKGROUND: Peritoneal dialysis (PD) is a widely employed renal replacement modality. A prospective study was conducted to determine the short-term and midterm outcomes and complication rates associated with a standardized optimal laparoscopic peritoneal dialysis catheter placement technique. METHODS: All patients undergoing laparoscopic PD catheter placement by one surgeon using our standardized method over a 5-year period were entered into a prospective database. Patients were evaluated preoperatively and postoperatively through office visits. Development of complications was assessed using follow up telephone or mail surveys. RESULTS: A total of 100 patients with a mean age of 56 years underwent laparoscopic PD catheter placement over the 5-year study period. In total, 103 laparoscopic PD catheter placement attempts were made in 100 patients. Placement was successful in 98 (95.1%) attempts and no placement required conversion to an open operation. Omentopexy was performed in 82 (83.7%) patients. There was no mortality reported within 30 days of the index operation. For patients who successfully underwent laparoscopic PD placement, early complications developed in 9 (9.2%) patients, of which 6 (6.1%) complications were directly related to the PD catheter. Midterm complications developed in 25 (25.5%) patients. Complication-related catheter repositioning was required for 12 (12.2%) catheters and catheter-related complication removal was required for 18 (18.4%) catheters. CONCLUSION: Laparoscopic placement of PD catheters can be successfully performed using a combination of described standardized laparoscopic maneuvers for optimal placement resulting in acceptable perioperative and short and midterm complication rates with negligible mortality rates.

Measurement of N-acetylaspartylglutamate in the human frontal brain by 1H-MRS at 7 T.

N-Acetylaspartylglutamate in human brain has been measured with difference editing at 7 T. The CH(2) proton resonances (∼ 2.5 ppm) of the aspartyl groups of N-acetylaspartylglutamate and N-acetylaspartate were difference edited (MEGA) using 20-msec gaussian radiofrequency pulses for selective 180 ° rotations of the coupling partners at 4.61 and 4.38 ppm, respectively. The echo time of the editing sequence, 108 msec, was obtained in phantom tests. Single-voxel localized in vivo measurements were conducted in the medial prefrontal and right frontal cortices of five healthy volunteers. The gray and white matter fractions within the voxels were obtained from T(1)-weighted image segmentation. Using linear regression of the metabolite concentration vs. fractional white matter contents within the voxels, the N-acetylaspartylglutamate-to-N-acetylaspartate concentration ratios in gray and white matter were estimated to be 0.13 and 0.28 by difference editing (95% confidence intervals 0.07-0.19 and 0.22-0.34), respectively, assuming identical relaxation effects between the metabolites.

Improvement of resolution for brain coupled metabolites by optimized (1)H MRS at 7T.

Resolution enhancement for glutamate (Glu), glutamine (Gln) and glutathione (GSH) in the human brain by TE-optimized point-resolved spectroscopy (PRESS) at 7 T is reported. Sub-TE dependences of the multiplets of Glu, Gln, GSH, γ-aminobutyric acid (GABA) and N-acetylaspartate (NAA) at 2.2-2.6 ppm were investigated with density matrix simulations, incorporating three-dimensional volume localization. The numerical simulations indicated that the C4-proton multiplets can be completely separated with (TE(1), TE(2)) = (37, 63) ms, as a result of a narrowing of the multiplets and suppression of the NAA 2.5 ppm signal. Phantom experiments reproduced the signal yield and lineshape from simulations within experimental errors. In vivo tests of optimized PRESS were conducted on the prefrontal cortex of six healthy volunteers. In spectral fitting by LCModel, Cramér-Rao lower bounds (CRLBs) of Glu, Gln and GSH were 2 ± 1, 5 ± 1 and 6 ± 2 (mean ± SD), respectively. To evaluate the performance of the optimized PRESS method under identical experimental conditions, stimulated-echo spectra were acquired with (TE, TM) = (14, 37) and (74, 68) ms. The CRLB of Glu was similar between PRESS and short-TE stimulated-echo acquisition mode (STEAM), but the CRLBs of Gln and GSH were lower in PRESS than in both STEAM acquisitions.

Prevalence of Upper Gastrointestinal Pathology in Patients with Obesity on Preoperative Endoscopy.

BACKGROUND AND OBJECTIVES: The preoperative work up for bariatric surgery is variable and not all centers perform a preoperative upper gastrointestinal endoscopy. A study was undertaken to determine the frequency of clinically significant gross endoscopic and pathological diagnoses in a large sample of patients with obesity undergoing work-up for bariatric surgery. METHODS: Routine endoscopy was performed on all preoperative bariatric patients. A retrospective chart review of 1000 consecutive patients was performed. Patients were divided into three groups: Group A (no endoscopic findings), Group B (clinically insignificant findings), Group C (clinically significant findings). RESULTS: Patients had a mean body mass index (BMI) of 49 kg/m2 and 79% were female. In this sample one finding was found on preoperative EGD in 95.2% of patients, 33.9% had at least two diagnoses, and 29.9% had three or more diagnoses. Group A (no findings) consisted of 4.8% of patient, 52.5% in Group B (clinically insignificant findings), and 42.7% were in Group C (clinically significant findings). Clinically significant findings included hiatal hernia 23.5%, esophagitis 9.5%, H. pylori 7.1%, gastric erosions 5.7%, duodenitis 3.7%, Barrett's esophagus 3.1%, and Schatzki ring 1.2%. There was no significant correlation between preoperative BMI and any endoscopic findings (all p-value 0.05). Patients in Group C were statistically older than Groups A and B. CONCLUSION: Upper gastrointestinal pathology is highly common in patients with obesity. There is a significant rate of clinically significant endoscopy findings and all bariatric surgery patients should undergo preoperative endoscopy.

Reoperations for Long-Term Complications Following Laparoscopic Adjustable Gastric Banding: Analysis of Incidence and Causality.

BACKGROUND: Laparoscopic adjustable gastric banding (LAGB) gained popularity in the early 2000s as a purely restrictive procedure with modest weight loss. The potential for complications requiring reoperation has since become evident. A retrospective review was performed to determine the incidence of long-term complications and predictive factors requiring surgical reintervention after LAGB. METHODS: Institutional review board approval was obtained, and a retrospective review of 200 consecutive patients undergoing LAGB over a period of six years was conducted at a single institution with American Society of Metabolic and Bariatric Surgery Center of Excellence designation. Data were collected on patient characteristics, comorbid conditions and complications requiring reintervention. Statistical analysis was performed using SPSS Statistics software (IBM Corp., Armonk, NY). RESULTS: Of the 200 patients, 176 (90.7%) were female with an average age of 53.6 years and preoperative body mass index (BMI) of 44.2 kg/m2. The average follow-up was 46 months. Complications occurred in 55 (28.4%) patients with band slippage/prolapse as the most common need for reoperation. Younger age, lack of comorbidities and diet/exercise compliance were associated with reintervention. CONCLUSIONS: LAGB has a high rate of reoperation secondary to complications associated with younger age. Alternative bariatric procedures may be more appropriate in these patients who have fewer comorbid conditions and are motivated to improve his or her health.

Measurement of glycine in human prefrontal brain by point-resolved spectroscopy at 7.0 tesla in vivo.

Measurement of glycine in human frontal brain by an optimized point-resolved spectroscopy sequence at 7 T is reported. Echo time dependencies of the overlapping coupled resonances of myo-inositol, free choline, and threonine were investigated with density matrix simulations, incorporating the slice-selective radiofrequency and gradient pulses. The numerical simulations indicated that the selectivity of the 3.55-ppm glycine singlet is maximized at (TE(1), TE(2)) = (101, 51) ms. Phantom experiments indicated that the myo-inositol peak amplitude between 3.5 and 3.6 ppm is reduced by a factor of 30 following the optimized point-resolved spectroscopy, as predicted by the simulation. From LCModel analyses, the glycine concentration in the medial prefrontal cortex in healthy adults was estimated, with a mean Cramér-Rao lower bound of 7 +/- 1% (mean +/- standard deviation; n = 7), to be 0.8 +/- 0.1 mM, with reference to total creatine at 8 mM.

In vivo detection of serine in the human brain by proton magnetic resonance spectroscopy (1H-MRS) at 7 Tesla.

A single-voxel proton magnetic resonance spectroscopy ((1)H-MRS) filtering strategy for in vivo detection of serine (Ser) in human brain at 7T is proposed. Spectral difference of coupled resonances arising from different subecho times of triple refocusing at a constant total echo time (TE) was utilized to detect the Ser multiplet and cancel the overlapping creatine (Cr) 3.92-ppm singlet via difference editing. Dependence of the Ser signal on subecho times was investigated using density-matrix simulation incorporating the slice-selective radio frequency (RF) pulses. The simulation indicated that the difference-edited Ser CH(2) multiplet at approximately 3.96 ppm is maximized with (TE(1), TE(2), TE(3)) = (54, 78, 78) and (36, 152, 22) ms. The edited Ser peak amplitude was estimated, with both numerical and phantom analyses of the performance, as 83% with respect to 90 degrees acquisition for a localized volume, ignoring relaxation effects. From the area ratio of the edited Ser and unedited Cr 3.03-ppm peaks, assuming identical T(1) and T(2) between Ser and Cr, the Ser-to-Cr concentration ratio for the frontal cortex of healthy adults was estimated to be 0.8 +/- 0.2 (mean +/- SD; N = 6).

Angiosarcoma complicating systemic sclerosis: a case report.

Cutaneous angiosarcoma is a rare malignant vascular tumor with a poor prognosis, most commonly affecting elderly white men. Diagnosis usually is delayed because the tumor has a highly variable and often innocuous presentation. Cutaneous angiosarcoma has been associated with a number of conditions and factors, including chronic lymphedema, prior radiation therapy, exposure to chemicals, and vascular malformations. We report the case of a 40-year-old black man with systemic sclerosis (SSc) who developed a cutaneous angiosarcoma in an area of sclerodermatous scalp. We propose that vascular endothelial growth factor (VEGF) overexpression in sclerodermatous skin may predispose a patient to the development of vascular tumors, such as angiosarcoma. Because early diagnosis and treatment positively impact survival outcome in patients with angiosarcoma, it is essential that physicians recognize the association of angiosarcoma and SSc and maintain a low threshold for performing a biopsy when suspicious lesions are present on sclerodermatous skin.

Perioperative medicine: a new model of care?

The discipline of perioperative medicine provides a foundation for the consistent delivery of safe and good quality care to surgical patients. Its goals include the identification and optimal care of the high-risk surgical patient, fostering patient-centred decision making throughout the surgical perioperative pathway, and reducing unwarranted variation in practice. In turn, this should reduce preventable complications and improve patient satisfaction, long-term morbidity and survival. This review concludes a series of articles which have described the epidemiology of surgical disease, the growth in the objective means of risk assessment, and novel outcome measures. It describes shortcomings in current practice, and how perioperative care pathways may overcome these. It discusses the growth of enhanced recovery programmes, which exemplify many of the sub-specialty's principles of patient-centred and coordinated care. Reported initiatives to modify local health-care systems, such as the Perioperative Surgical Home, are presented. Consideration is given to how clinicians can use the philosophy and tools of quality improvement methodology, with important current examples. The article concludes by looking at obstacles to change when introducing new frameworks and the future horizons for the discipline.

CIDI-lung-seg: a single-click annotation tool for automatic delineation of lungs from CT scans.

Accurate and fast extraction of lung volumes from computed tomography (CT) scans remains in a great demand in the clinical environment because the available methods fail to provide a generic solution due to wide anatomical variations of lungs and existence of pathologies. Manual annotation, current gold standard, is time consuming and often subject to human bias. On the other hand, current state-of-the-art fully automated lung segmentation methods fail to make their way into the clinical practice due to their inability to efficiently incorporate human input for handling misclassifications and praxis. This paper presents a lung annotation tool for CT images that is interactive, efficient, and robust. The proposed annotation tool produces an "as accurate as possible" initial annotation based on the fuzzy-connectedness image segmentation, followed by efficient manual fixation of the initial extraction if deemed necessary by the practitioner. To provide maximum flexibility to the users, our annotation tool is supported in three major operating systems (Windows, Linux, and the Mac OS X). The quantitative results comparing our free software with commercially available lung segmentation tools show higher degree of consistency and precision of our software with a considerable potential to enhance the performance of routine clinical tasks.

Measurement of glutathione in human brain at 3T using an improved double quantum filter in vivo.

A single voxel proton NMR double quantum filter (DQF) for measurement of glutathione (GSH) in human brain at 3T is reported. Yield enhancement for the CH(2) resonances of the cysteine moiety at 2.95ppm has been achieved by means of dual encoding. After the preparation of double quantum and zero quantum coherences (DQC and ZQC) at equal magnitude, the first DQC encoding was followed by interchange of DQC and ZQC, and another DQC encoding. The multi-quantum coherences were fully utilized to generate a GSH target signal at approximately 2.95ppm. The optimal echo time and the editing efficiency were obtained with numerical analysis of the filtering performance and phantom measurements. The dual-DQC encoding method provided GSH yield greater by a factor of 2.1 than single-DQC encoding for identical slice-selective RF pulses in phantom tests. Using the phantom relaxation times and the ratio of edited GSH to N-acetylaspartate (NAA) 2.0-ppm peak areas, the concentration of GSH in the medial parietal cortex of the healthy human brain in vivo was estimated to be 1.0+/-0.3mM (mean+/-SD, n=7), with reference to NAA at 10mM.

MC-1 (pyridoxal 5'-phosphate): novel therapeutic applications to reduce ischaemic injury.

Despite the overall efficacy of mechanical reperfusion therapies, such as percutaneous coronary intervention and coronary artery bypass graft surgery, in reducing the morbidity and mortality that is associated with acute ischaemic syndromes, many of the treated patients develop ischaemia-reperfusion injury due to impaired microvascular integrity, embolisation of atherothrombotic debris and/or disrupted end-organ metabolism. MC-1 is an investigational drug from Medicure, Inc. In preclinical models of ischaemia and ischaemia-reperfusion injury, treatment with MC-1 has demonstrated significant cardio- and neuroprotective effects. Although the pharmacological activity of MC-1 may involve multiple mechanisms, research suggests that at least part of the protective effect may be mediated through its actions on purinergic receptors. Early clinical experience with MC-1 also appears to be promising: in a recent Phase II evaluation, treatment with MC-1 was associated with a statistically significant reduction in periprocedural infarct size (as measured by area under the curve creatine kinase-myocardial band) among high-risk patients undergoing elective percutaneous coronary intervention. Based on these findings, larger, randomised trials to confirm the safety and efficacy of MC-1 in the setting of coronary artery revascularisation with coronary artery bypass graft, acute coronary syndromes and stroke are ongoing or in development. These forthcoming evaluations should clarify the safety and efficacy of MC-1 and improve the understanding regarding its potential therapeutic role in a variety of clinical settings and indications.

Increase in the beta chain of hepatocyte growth factor (HGF beta) precedes c-met expression after bleomycin-induced lung injury in the rat.

After lung injury the regeneration of the alveolar epithelium is highly dependent on the proliferation of type II alveolar epithelial cells (AECs). Hepatocyte growth factor (HGF), a potent epithelial cell mitogen, is present as a single chain in normal tissue, but after injury HGF is converted to an active form composed of an alpha and a beta chain. In this study it was demonstrated that there was an increase in the beta chain of HGF 4 days after bleomycin administration, coinciding with the time of maximal type II AEC proliferation. Bronchoalveolar lavage fluid (BALF) obtained 4 days after bleomycin administration was maximally mitogenic to L2 cells, a nontransformed rat alveolar epithelial cell line. Type II cells isolated from normal rats do not express the HGF receptor, c-met. However, 4 days after bleomycin injury, using Western blot analysis, an increase in c-met was detected in AEC protein extracts. HGF induced c-met expression by L2 cells and neutralizing antibodies to HGF inhibited the mitogenic activity in the BALF. These findings suggest that HGF may regulate its own receptor on AECs and is an important mitogen for AECs 4 days after bleomycin administration.