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Background/Objectives: Obesity has been associated with both changes in adipose tissue lipid metabolism and inflammation. A key class of lipid-derived signalling molecules involved in inflammation are the prostaglandins. In this study, we aimed to determine how obesity affects the levels of prostaglandins within white adipose tissue (WAT) and determine which cells within adipose tissue produce them. To avoid the effects of cellular stress on prostaglandin levels, we developed a multivariate statistical approach in which metabolite concentrations and transcriptomic data were integrated, allowing the assignment of metabolites to cell types. Subjects/Methods: Eicosanoids were measured by liquid chromatography-tandem mass spectrometry and mRNA levels using real-time PCR. Eicosanoid levels and transcriptomic data were combined using principal component analysis and hierarchical clustering in order to associate metabolites with cell types. Samples were obtained from C57Bl/6 mice aged 16 weeks. We studied the ob/ob genetically obese mouse model and diet-induced obesity model. We extended our results in mice to a cohort of morbidly obese humans undergoing bariatric surgery. Results: Using our modelling approach, we determined that prostglandin D2 (PGD2) in adipose tissue was predominantly produced in macrophages by the haematopoietic isoform of prostaglandin D synthase (H-Pgds). Analysis of sub-fractionated WAT confirmed that H-Pgds was expressed in adipose tissue macrophages (ATMs). Furthermore, H-Pgds expression in ATMs isolated from lean and obese mice was consistent with it affecting macrophage polarisation. Functionally, we demonstrated that H-PGDS-produced PGD2 polarised macrophages toward an M2, anti-inflammatory state. In line with a potential anti-inflammatory role, we found that H-PGDS expression in ATMs was positively correlated with both peripheral insulin and adipose tissue insulin sensitivity in humans. Conclusions: In this study, we have developed a method to determine the cellular source of metabolites within an organ and used it to identify a new role for PGD2 in the control of ATM polarisation.

The functional genomic techniques of transcriptomics and proteomics promise unparalleled global information during the drug development process. However, if these technologies are used in isolation the large multivariate data sets produced are often difficult to interpret, and have the potential of missing key metabolic events (e.g. as a result of experimental noise in the system). To better understand the significance of these megavariate data the temporal changes in phenotype must be described. High resolution 1H NMR spectroscopy used in conjunction with pattern recognition provides one such tool for defining the dynamic phenotype of a cell, organ or organism in terms of a metabolic phenotype. In this review the benefits of this metabonomics/metabolomics approach to problems in toxicology will be discussed. One of the major benefits of this approach is its high throughput nature and cost effectiveness on a per sample basis. Using such a method the consortium for metabonomic toxicology (COMET) are currently investigating approximately 150 model liver and kidney toxins. This investigation will allow the generation of expert systems where liver and kidney toxicity can be predicted for model drug compounds, providing a new research tool in the field of drug metabolism. The review will also include how metabonomics may be used to investigate co-responses with transcripts and proteins involved in metabolism and stress responses, such as during drug induced fatty liver disease. By using data integration to combine metabolite analysis and gene expression profiling key perturbed metabolic pathways can be identified and used as a tool to investigate drug function.

The authors report on a technique for the treatment of symptomatic, chronic complete dislocations of the acromioclavicular joint. The coracoacromial ligament is substituted for the coracoclavicular ligaments, and a special temporary coracoclavicular lag screw is used to stabilize the clavicle to the coracoid during ligament healing. The technique has been used on 23 patients who were observed for an average of 5.2 years. Good to excellent results were obtained in 19 of 23 patients. The four patients with fair or poor results had one or more resections of the distal clavicle before the reconstruction. Subjectively, 22 of 23 patients reported improvement in their shoulder.

Ovarian serous tumors of low malignant potential (STLMP) occasionally progress; a small percentage of patients die of the tumor. There is no known way to predict which tumors will progress.Forty STLMP were analyzed by DNA flow cytometry and compared with 26 serous carcinomas.Forty percent of Stage I STLMP and 40% of Stage III STLMP were DNA aneuploid as compared to 54% of serous carcinomas. Aneuploidy was found in 50% of STLMP that progressed and in 38% of neoplasms that did not progress. Four of the 30 Stage I STLMP progressed, and 3 of the 4 were aneuploid; whereas, of the 26 Stage I STLMP that did not progress, 9 were DNA aneuploid. Stage III STLMP were aneuploid in 4 out of 10 instances (40%). Aneuploidy was not related to progression as three of four DNA diploid tumors progressed, and three of six that did not progress were aneuploid. Thirteen of 16 aneuploid STLMP had peridiploid aneuploid populations. The mean follow-up periods were 14.3 years for Stage I STLMP and 8.3 years for Stage III STLMP:DNA aneuploidy in Stages I and III STLMP does not identify neoplasms likely to relapse with sufficient frequency to be useful in identifying those patients at high risk for relapse.

Summary: In order to determine the potential usefulness of the Mini-Mult as a screening instrument with parents of emotionally disturbed children, two studies were conducted. In the first study 128 MMPI profiles were rescored for the Mini-Mult and comparisons with MMPI were made. In the second study 50 parents were administered both the MMPI and the Mini-Mult. Results of both studies indicate that the Mini-Mult is not a good screening instrument with parents of emotionally disturbed children.

Procedures for staining frozen sections of human muscle biopsy specimens for adenylate deaminase are outlined. The preeminent role of this procedure is as a survey stain for myoadenylate deaminase deficiency, a new and common muscle enzyme deficiency, an example of which is illustrated. Discrimination of type I and II muscle fibers with this stain is based on color differences rather than density differences. Color photomicrographs illustrate the variations in staining that may be encountered, and experimental controls to verify the validity of the stain are summarized.

In infantile acid maltase deficiency (AMD), masses of glycogen accumulate in muscle fibers and are then gradually digested. The metachromatic material found in some glycogen-filled fibers, not previously studied with the electron microscope, has two different fine structural appearances. Some is similar in shape and size to glycogen beta granules, but is more intensely stained, and some is in larger granules, irregular in shape, and has even higher stain affinity. Since acid maltase deficiency was identified by Hers, others have proposed that more than one genetic defect or additional extralysosomal factors are required to account for massive glycogen accumulation and metachromasia. There is no direct evidence of additional rare genetic defects. Presented herein are two simple proposals consistent with the primary deficiency. The first is that some partly digested glycogen is condensed and that this concentrates the sites that bind dye, producing metachromasia and other differences from normal glycogen. The second is that the massive accumulation of glycogen in muscle fibers involves, in addition to previously recognized lysosomal storage and lysosomal rupture, inactivation of sarcoplasmic phosphorylase caused by disruption of excitation-contraction linkages. These two proposals are physiologically plausible and potentially testable and do not invoke the coincidence of two or more rare genetic mutations.

Infantile acid maltase deficiency (Pompe's disease, glycogenosis II) is a progressive, severe lysosomal storage disease in which skeletal and cardiac muscle fibers accumulate membrane-bound and free glycogen and are destroyed. New information in this report concerns 1) early hypertrophy of skeletal muscle fibers, 2) absence of size change as glycogen is lost, and 3) the ultrastructure of end-stage fibers empty of glycogen. Muscle fibers enlarge as they accumulate glycogen and then stay large as glycogen is lost. They are so large that, if empty fibers did in fact contain glycogen, over 80% of the muscle would be glycogen instead of 6.3-11.5% (from 37 published determinations). Fibers that have reached "empty" end-stage are shown to be more numerous than all other stages combined in biopsies from infantile acid maltase deficiency. Ultrastructurally, end-stage fibers contain much "empty" space (liquid-filled without fine structure) and various remnants and masses of altered myofibrillar and sarcoplasmic material. Many broken membranes originally enclosing glycogen in storage lysosomes are seen. A single broken membrane can enclose an area larger than the cross section area of a muscle fiber from a normal infant. The results support the proposal of Hers that the disease is due to a deficiency of the single lysosomal enzyme acid maltase. The results also support the lysosomal rupture hypothesis of Griffin, which accounts for muscle fibers being more damaged than are other cells and for the release of glycogen to the sarcoplasm.

The findings of the present study are consistent with those of previous studies with the Mini-Mult short form. The correspondence is too low and variable to allow the short forms to be used in place of the MMPI with parents of emotionally disturbed children.