Water-fat magnetic resonance imaging quantifies relative proportions of brown and white adipose tissues: ex-vivo experiments

Quantifying the amount of brown adipose tissue (BAT) within white adipose tissue (WAT) in human depots may serve as a target to combat obesity. We aimed to quantify proton density fat fraction (PDFF) of BAT and WAT in relatively pure and in mixed preparation using water–fat imaging. Three ex-vivo experiments were performed at 3 T using excised interscapular BAT and inguinal/subcutaneous WAT from mice. The first two experiments consisted of BAT and WAT in separate tubes, and the third used mixed preparation with graded quantities of BAT and WAT. To investigate the influence of partial volume on PDFF metrics, low (2.66  mm3) and high spatial resolution (0.55  mm3 acquired voxels) in two orthogonal three-dimensional sections were compared. The low-resolution acquisitions are corrected for T2* and multipeak lipid spectrum, thus considered “quantitative,” whereas the high-resolution acquisitions are not corrected but were performed to better spatially segment BAT from WAT zones. As potential BAT metrics, we quantified the average PDFF and the volume of tissue having PDFF ≤50% (VOLPDFF≤50%) based on the PDFF histogram. In the first experiment, the average PDFF of BAT was 23±6% and 21±7.6% and the average PDFF of WAT was 76±7% and 87±7% using high- and low-resolution techniques, respectively. A similar trend with excellent reproducibility in average PDFF of BAT and WAT was observed in the second experiment. In the third experiment over the four acquisitions, the BAT-dominant tube demonstrated lower PDFF (mean ± SD) of 55±2% than WAT-dominant (69±4%) and WAT-only tubes (88±4%). Estimating VOLPDFF≤50%, the BAT-dominant tube demonstrated higher volume of 0.26  cm3 than WAT-dominant (0.16  cm3) and WAT-only tubes (0.01  cm3). The presence of BAT exhibits a lower PDFF relative to WAT, thus allowing segmentation of low PDFF tissue for quantification of volume representative of BAT. Future studies will determine the clinical relevance of BAT volume within human depots.

Incidental Anatomic Finding of Celiacomesenteric Trunk Associated with 'Nutcracker Phenomenon,' or Compression of the Left Renal Vein

Patient: Female, 91

Final Diagnosis: Nutcracker syndrome • celiacomesenteric trunk

Symptoms: Dyspepsia • dysphagia

Medication: —

Clinical Procedure: —

Specialty: Surgery

Intrathoracic Fat Measurements Using Multidetector Computed Tomography (MDCT): Feasibility and Reproducibility

Intrathoracic fat volume, more specifically, epicardial fat volume, is an emerging imaging biomarker of adverse cardiovascular events. The purpose of this work is to show the feasibility and reproducibility of intrathoracic fat volume measurement applied to contrast-enhanced multidetector computed tomography images. A retrospective cohort study of 62 subjects free of cardiovascular disease (55% females, age = 49 ± 11 years) conducted from 2008 to 2011 formed the study group. Intrathoracic fat volume was defined as all fat voxels measuring −50 to −250 Hounsfield Unit within the intrathoracic cavity from the level of the pulmonary artery bifurcation to the heart apex. The intrathoracic fat was separated into epicardial and extrapericardial fat by tracing the pericardium. The measurements were obtained by 2 readers and compared for interrater reproducibility. The fat volume measurements for the study group were 141 ± 72 cm³ for intrathoracic fat, 58 ± 27 cm³ for epicardial fat, and 84 ± 50 cm³ for extrapericardial fat. There was no statistically significant difference in intrathoracic fat volume measurements between the 2 readers, with correlation coefficients of 0.88 (P = .55) for intrathoracic fat volume and −0.12 (P = .33) for epicardial fat volume. Voxel-based measurement of intrathoracic fat, including the separation into epicardial and extrapericardial fat, is feasible and highly reproducible from multidetector computed tomography scans.

Development of a bone substitute material based on alpha-tricalcium phosphate scaffold coated with carbonate apatite/poly-epsilon-caprolactone

Interconnected porous tricalcium phosphate ceramics are considered to be potential bone substitutes. However, insufficient mechanical properties when using tricalcium phosphate powders remain a challenge. To mitigate these issues, we have developed a new approach to produce an interconnected alpha-tricalcium phosphate (α-TCP) scaffold and to perform surface modification on the scaffold with a composite layer, which consists of hybrid carbonate apatite / poly-epsilon-caprolactone (CO3Ap/PCL) with enhanced mechanical properties and biological performance. Different CO3Ap combinations were tested to evaluate the optimal mechanical strength and in vitro cell response of the scaffold. The α-TCP scaffold coated with CO3Ap/PCL maintained a fully interconnected structure with a porosity of 80% to 86% and achieved an improved compressive strength mimicking that of cancellous bone. The addition of CO3Ap coupled with the fully interconnected microstructure of the α-TCP scaffolds coated with CO3Ap/PCL increased cell attachment, accelerated proliferation and resulted in greater alkaline phosphatase (ALP) activity. Hence, our bone substitute exhibited promising potential for applications in cancellous bone-type replacement.

A prospective, multidisciplinary evaluation of premenopausal women with iron-deficiency anemia

OBJECTIVE

The cause of iron deficiency anemia (IDA) in premenopausal women is often presumed to be menstrual blood loss. The purpose of this study was to determine the diagnostic value of a comprehensive gynecological and gastrointestinal evaluation in premenopausal women with IDA.

METHODS

Nineteen premenopausal, nonpregnant women older than 18 yr of age with IDA defined by a hemoglobin < 12 gm/dl with serum ferritin < 10 ng/ml participated in the study. Evaluations included directed history and physical examination by a specialist in gynecology and a subspecialist in gastroenterology, esophagogastroduodenoscopy, colonoscopy, upper gastrointestinal radiography with small bowel follow-through, antiendomysial antibody, and fecal occult blood tests.

RESULTS

Seven of 19 (37%) premenopausal women with IDA were diagnosed to have a gynecological cause of anemia by a specialist in that field. Although only four of these seven patients had digestive complaints, all but one (86%) were discovered to have gastrointestinal disease by upper endoscopy; findings were duodenal ulcer and Helicobacter pylori (H. pylori) gastritis (one), esophagitis and H. pylori gastritis (one), erosive esophagitis (one), gastric arteriovenous malformations (one), and nodular/erosive H. pylori gastritis (two). Fecal occult blood testing was positive in only two (29%) subjects; upper endoscopy revealed erosive esophagitis and gastric arteriovenous malformations. Twelve of the 19 (63%) premenopausal women with IDA were not diagnosed to have a gynecological source of anemia by a specialist in that field. Fecal occult blood testing was negative among all women tested and the only digestive complaint was heartburn (pyrosis) in seven. Each was identified to have esophagitis, duodenal ulcer, or gastritis by upper endoscopy. Colonoscopic examination of the 12 subjects without gynecologic etiology for IDA revealed pan colitis (one), diverticulosis (one), diverticulosis and melanosis coli (one), hyperplastic polyps (one), and nodular lymphoid aggregates (one).

CONCLUSIONS

Significant upper gastrointestinal disease is identifiable among most premenopausal women with IDA (18 of 19 or 95%), even when careful evaluation by a specialist in gynecology suggests a gynecological source. Upper endoscopy should be considered in the evaluation of all premenopausal women with IDA expressing digestive complaints or in those with IDA refractory to iron supplementation. Lower endoscopic examination may be reserved for those women with symptoms or signs suggestive of colorectal disorders.

Gluten-sensitive enteropathy in patients with insulin-dependent diabetes mellitus

OBJECTIVE

To determine the prevalence of celiac disease in a cohort of patients with insulin-dependent diabetes mellitus and to describe the clinical characteristics of patients with coexistent disease.

DESIGN

Prospective cohort study.

SETTING

U.S. Army medical center.

PATIENTS

47 patients with insulin-dependent diabetes mellitus.

MEASUREMENTS

Antiendomysial antibody testing was used to screen for celiac disease. The diagnosis of celiac disease required histologic evidence of villous atrophy and crypt hyperplasia and a positive antiendomysial antibody test result. In patients identified as having coexistent disease, complete blood counts, multiphasic biochemical testing, D-xylose absorption testing, and bone mineral density estimates were done.

RESULTS

3 of 47 patients with insulin-dependent diabetes mellitus (6.4%; 95% CI, 1.4% to 17.5%) had positive antiendomysial antibody test results and small-bowel biopsy specimens consistent with celiac disease. The 95% CI lies entirely above the estimated prevalence of celiac disease expected in the general U.S. population, which ranges from 0.02% to 0.1%. Mean bone mineral densities were 0.8 and 1.1 SD below age-, ethnicity-, and sex-matched controls in each of the 2 antiendomysial antibody-positive patients tested. Small bowel absorption was abnormal in 1 of the 2 patients tested by D-xylose. Anemia and hypoalbuminemia were not detected in any of the patients with coexistent disease. Only 1 of the 3 patients had symptoms of diarrhea. All patients were at or above their ideal body weights.

CONCLUSIONS

Celiac disease appears to be more common among patients with insulin-dependent diabetes mellitus than in the general U.S. population (p less than 0.001). Two of the three patients with coexistent disease in this study had subclinical or latent celiac disease.

A case of multicentric reticulohistiocytosis with thyroid involvement

A case of multicentric reticulohistiocytosis with thyroid involvement is reported. This systemic condition has an unknown cause and is manifested by the development of nodules containing an infiltrate of characteristic histiocytic and multinucleated giant cells in the synovium, skin, subcutaneous tissues, and occasionally bone or other tissues.

Curable cancers and fatal ulcers. Attitudes toward cancer in Japan

Japanese patients having terminal cancer are generally not told their true diagnosis. Japanese physicians deem it unethical to reveal a 'death sentence' and the patient's family provides support by reassuring the patient that he will recover. This behavior, strange to many Americans, seems best explained by a symbolic interactionist approach. The Japanese public views cancer as a polluting force leading to death. Family members express their concern in this stressful situation, not by open verbal communication, but by immersing themselves in proper role behavior. The patient also has a specific role in the deception, although he may suspect the true diagnosis. An ironic situation results in that an 'independent' American patient has wider opportunities for support as death approaches, but a 'dependent' Japanese patient faces death alone. As cancer technology changes public images, we suspect that cancer will be more openly discussed. Yet the symbolic behavior that surrounds cancer in Japan today will continue whenever death is seen as prolonged, deforming, and uncontrollable.