Ultrasound accuracy for brachial plexus pathology.

AIM: To determine (a) the accuracy of ultrasound in detecting brachial plexus pathology and (b) outline the advantages and limitations of ultrasound compared to MRI for imaging the brachial plexus. MATERIAL AND METHODS: cases with clinically suspected brachial plexus pathology were evaluated first by ultrasound, followed by MRI. Patients with prior brachial plexus imaging were excluded. The final diagnosis was based on a combination of ultrasound, MRI, clinical follow-up, and surgical findings. The accuracy of the ultrasound was assessed by comparing the ultrasound and the final diagnoses. The mean clinical follow-up time following ultrasound was 1.8 ± 1.4 years. RESULTS: Ninety-two (64%) of the 143 cases had normal brachial plexus ultrasound and MRI examinations. Fifty-one (36%) of 143 cases had brachial plexus pathology on MRI, comprising post-radiation fibrosis (n=25, 49%), nerve sheath tumor (n=11, 21%), traumatic injury (n=7, 14%), inflammatory polyneuropathy (n=4, 8%), malignant infiltration (n=2, 4%), desmoid fibromatosis (n=1,2%), and neuralgic amyotrophy (n=1, 2%). Overall diagnostic accuracy of ultrasound for brachial plexus pathology was 98% (140/143), with three discordant cases (neuralgic amyotrophy n=1, inflammatory neuropathy n=1, postradiation fibrosis n=1) regarded as normal on ultrasound assessment. Sensitivity, specificity, and positive and negative predictive value of ultrasound for identifying brachial plexus pathology were 94%, 100%, 100%, and 97%, respectively. CONCLUSION: Ultrasound identifies brachial plexus pathology with high accuracy and specificity, showing comparable diagnostic efficacy to MRI. Ultrasound can serve as an effective first-line imaging investigation for suspected brachial plexus pathology.

Community-Based Peer-Led Intervention for Healthy Ageing and Evaluation of the 'HAPPY' Program.

OBJECTIVES: Population ageing impacts many areas of society from health and social care cost to housing and future workforce, and whole-of-society approach is required to promote healthy ageing. The Decade of Healthy Ageing report has called upon multi-sectoral collaboration to promote age-friendly communities. The Healthy Ageing Promotion Program for You (HAPPY) is a community-based dual-task exercise program for older adults led by health coaches (HC) or trained volunteers (HAPPY leaders) to promote healthy ageing. The primary objective was to observe improvement in cognition. The secondary objective was to observe improvement in frailty status, functional status, perceived health and reduction of social isolation. We also aim to evaluate the effectiveness and describe the implementation of the HAPPY program. DESIGN: To engage older adults with prefrailty, frailty and/or cognitive impairment in dual-task exercise program. Recruitment and publicity were through country-wide multisectoral collaboration. SETTING: Community setting. PARTICIPANTS: More than 700 older adults participated in ≥ 50 different sites including senior activity centres. Five hundred and sixty-nine participants attended phase 1 screening. Pre-frail or frail ambulant participants or those with underlying cognitive impairment were invited to participate in phase 2 screening. Among them 296 participants enrolled in phase 2 with 66.6% follow up rate at 3 months. MEASUREMENTS: Phase 1 and 2 screening consisted of screening for frailty (FRAIL), cognition (Montreal Cognitive Assessment [MoCA]), falls, vision, grip strength, perceived health (EuroQol vertical visual analogue scale), depression (geriatric depression scale), social network (6-item Lubben Social Network Scale), gait speed and physical function (Short physical performance battery [SPPB]). RESULTS: HC led 61.7% of the participants, and HAPPY was conducted twice weekly for 64% of the participants. There was significant improvement in the MoCA scores both in the HC and HAPPY leaders' led groups. Overall physical function, chair-stand and balance domain improved significantly especially in the groups led by HC and those participating in twice-weekly exercises. There was significant improvement in perceived health, reduction in social isolation, improvement in frailty status and reduction of falls at 3 months. CONCLUSION: Community embedded peer-led program to promote healthy ageing like HAPPY can improve cognition, physical function, and frailty status, reduce social isolation, and improve perceived health. It takes a "village" to promote healthy ageing, and the need to have a life course approach to healthy longevity which must involve local government and ministerial organisations, non-profit organisations, industries, academia, and community to redesign health.

Sulfation in dog.

Sulfation has been thoroughly studied in several species including e.g. man and rat. However, one important species often used for pharmacological drug studies is the dog. Here we describe recent advances as well as older data in the field of dog sulfation. Species differences in sulfation have been reported. Stereoselectivity, inhibition by pentachlorophenol, bioactivation of DNA binding species, and gender differences have also been observed for canine sulfotransferases (SULTs). Several drugs are being sulfated in vivo in dog, e.g. xamoterol, 4'-hydroxypropanolol, paracetamol and salicylamide. However, studies have shown that also e.g. canine hepatocytes and liverslices will sulfate substrates e.g. paracetamol and 7-hydroxycoumarin in in vitro experiments. Recently, three different enzymes have been cloned and characterized from canine liver, cSULT1A1, cSULT1B1 and cSULT1D1. cSULT1A1 being very similar to the human ortholog in terms of substrate specificity and is also ubiquitously expressed in canine tissues. The cSULT1B1 enzyme is also very similar in both distribution pattern as well as substrate preference compared to the human ortholog. The third enzyme, cSULT1D1, sulfates dopamine with high efficiency and it has no counterpart in man since it is found as a pseudogene. The importance of amino acid residue 247 in cSULT1D1 will be discussed since it can alter the ratio of sulfation of dopamine versus para-nitrophenol. In addition, the phenomenon of the high expression of the canine enzymes in colon is discussed.

Thiazolidinediones reduce the LDL binding affinity of non-human primate vascular cell proteoglycans.

AIMS/HYPOTHESIS: Retention of atherogenic lipoproteins in the artery wall by proteoglycans is a key step in the development of atherosclerosis. Thiazolidinediones have been shown to reduce atherosclerosis in mouse models. The aim of this study was to determine whether thiazolidinediones modify vascular proteoglycan synthesis in a way that decreases LDL binding. METHODS: Primate aortic smooth muscle cells were exposed to troglitazone or rosiglitazone, or no stimulus at all for a 24-hour steady-state labelling period. Sulphate incorporation, size and LDL binding affinity of proteoglycans were determined. Proteoglycans secreted by cells in the presence or absence of troglitazone were separated into large and small classes by size exclusion chromatography, and LDL binding affinity was determined. RESULTS: Proteoglycans synthesised by cells exposed to troglitazone or rosiglitazone were smaller, with decreased sulphate incorporation and decreased LDL binding affinity. However, troglitazone had a greater effect than rosiglitazone. Troglitazone reduced the LDL binding affinities of both the large and small proteoglycans compared with control. The binding differences persisted when glycosaminoglycan chains released from proteoglycans were incubated with LDL, indicating that troglitazone affects the glycosaminoglycan synthetic machinery of these cells. CONCLUSIONS/INTERPRETATION: Thiazolidinediones decrease the LDL binding affinity of the proteoglycans synthesised by primate aortic smooth muscle cells. This could, in part, account for the reduced atherosclerosis observed in animal models.

Laparoscopy for the treatment of women with endometrial cancer.

OBJECTIVE: To evaluate the use of a laparoscopic approach for the management of endometrial cancer. DESIGN: Retrospective study. SETTING: Regional hospital, Hong Kong. SUBJECTS AND METHODS: Individual medical records of patients with preoperative histological diagnosis of endometrial carcinoma from January 2000 to December 2001 were reviewed and the data analysed. MAIN OUTCOME MEASURES: Success of laparoscopic-assisted surgical staging, intra-operative and postoperative morbidity, and length of hospital stay. RESULTS: Laparoscopic surgery was successful for 93.3% (28 of 30) patients. Two patients were converted to laparotomy. The mean operating time was 102 minutes (standard deviation, 16 minutes) and the mean operative blood loss was 280 mL (standard deviation, 137 mL). The mean hospital stay was 5 days (standard deviation, 2.3 days). The intra-operative and postoperative complication rate was 16.7%, including vaginal tear, injury to the inferior epigastric vessel, lymphocyst, and pulmonary embolism. CONCLUSION: This study illustrated that a laparoscopic approach is feasible for endometrial cancer surgery and may be considered as the primary treatment modality in skilled hands. This approach should be offered to women with endometrial cancer without contraindications for laparoscopic surgery if experienced endoscopic surgeons are available. Prophylaxis for venous thromboembolism and the use of retroperitoneal drainage may be helpful in decreasing the perioperative morbidity.

Helicobacter pylori infection in Chinese subjects with type 2 diabetes.

The relationship between diabetes and Helicobacter pylori (HP) infection is controversial. In this study, we examined the possible relationship between HP infection and type 2 diabetes in Chinese subjects. Sixty-three Chinese type 2 diabetic patients (mean age +/- SD: 49.9 +/- 12.0 years; range: 17-76 years) were recruited irrespective of the duration of diabetes or type of therapy. Twenty-nine (46%) of them had upper gastrointestinal symptoms and the other 34 (54%) did not. Another 55 age- and sex-matched non-diabetic subjects (mean age +/- SD: 45.6 +/- 15.6 years, p=0.098; range 18-79 years) with dyspepsia indicated for upper endoscopy were recruited as a comparison group. Upper endoscopy was performed with antral mucosal biopsy specimens taken for rapid urease test (CLO test). HP infection was considered to be present if the rapid urease test was positive. The rates of HP infection of the diabetic and non-diabetic individuals were 50.8% and 56.4% respectively (p: NS). The rate of HP infection was similar between the 2 groups of diabetic patients with or without gastrointestinal symptoms (42.9% vs. 56.3%, p: NS). Using logistic regression analysis (forward stepwise) with age, sex, glycaemic control, duration of diabetes and upper gastrointestinal symptoms as independent variables to predict the risk of HP infection in diabetic patients, none of the parameters enter into the model. In conclusion, the rate of HP infection in Hong Kong Chinese subjects with type 2 diabetes is around 50%, which is similar to control subjects. No association was found between HP infection, glycaemic status, and duration of diabetes and upper gastrointestinal symptoms in these diabetic subjects.

Identification of a new subfamily of sulphotransferases: cloning and characterization of canine SULT1D1.

Sulphation is an important conjugation pathway in drug metabolism that has been studied in several species including humans. However, few studies have been performed using the dog as a subject. In this report we describe the cloning and characterization of a canine cytosolic sulphotransferase (SULT). The overall primary structure of this enzyme is very similar to that of a rat phenol-sulphating enzyme found in the EMBL Database and to a mouse SULT termed amine-N-sulphotransferase (81% identity). The expressed canine SULT conjugates small phenols and aromatic amines such as dopamine, minoxidil, p-nitrophenol and 5-hydroxytryptamine, but not dehydroepiandrosterone or beta-oestradiol. These results are in agreement with the results reported for the mouse SULT. In contrast with the mouse enzyme, the canine SULT does not conjugate eicosanoid compounds, i.e. prostaglandins, thromboxane B(2) or leukotriene E(4). The canine SULT is expressed at high levels in the colon of both genders; it is also expressed in the small intestine, kidney and liver. Furthermore, because the canine, mouse and rat SULT forms exhibit significant sequence identity (more than 80%), they seem to represent a distinct group in the SULT family tree. This suggestion is strengthened by the low identity with other SULTs. The subfamily that is most similar to this new group is SULT1A, with approx. 60% similarity. However, the mouse and canine enzymes are not characterized by the efficient sulphation of p-nitrophenol, dopamine, beta-oestradiol or oestrone. Thus these results seem to exclude them from the SULT1A subfamily. We therefore propose a new subfamily in the phenol SULT family, designated SULT1D, and consequently the canine enzyme is termed SULT1D1.

Molecular cloning, expression, and characterization of a canine sulfotransferase that is a human ST1B2 ortholog.

Sulfation is an important conjugation pathway in deactivating thyroid hormones, keeping the proper hormonal balance, and increasing the rate of thyroid hormone metabolism. We have identified, cloned, and characterized a sulfotransferase (SULT) that is capable of thyroid hormone conjugation in the dog. This enzyme, designated cSULT1B1, displays a strong identity (>84%) to the human ST1B2 enzyme. However, cSULT1B1 displays less identity, about 73%, to mouse and rat orthologs. In addition, the canine enzyme is three amino acids shorter than the rodent ones but has the same length as the human ortholog, 296 amino acids. The bacterial expressed and partial purified cSULT1B1 enzyme sulfates p-nitrophenol and 1-naphtol, but not dopamine. The thyroid hormones 3,3'-diiodothyronine and 3,5,3'-triiodothyronine are efficiently sulfated. 3,3',5'-Triiodothyronine is sulfated to lesser degree while sulfation of 3,5'-diiodothyronine and 3,3',5,5'-tetraiodothyronine cannot be detected. The cSULT1B1 is found in the colon (highest level), kidney and small intestine in dogs, but surprisingly not in the male dog liver although low levels of immunoreactivity were detected in the female dog liver. The male dog expresses more of SULT1B1 enzyme in the lower part of the small intestine while the female dog displays an opposite pattern of expression. These results describe the cloning and characterization of a canine thyroid hormone sulfating enzyme that is more closely related to the human ortholog than to the rodent thyroid sulfating enzymes.

Oxidized low density lipoproteins regulate synthesis of monkey aortic smooth muscle cell proteoglycans that have enhanced native low density lipoprotein binding properties.

Oxidized low density lipoproteins (Ox-LDL) affect several biological processes involved in atherogenesis. However, it is not known whether Ox-LDL can regulate proteoglycan expression and thus affect arterial wall lipoprotein retention. This study evaluated whether Ox-LDL, as compared with native LDL, regulates proteoglycan expression by monkey arterial smooth muscle cells in vitro and whether proteoglycans synthesized in the presence of Ox-LDL exhibit altered lipoprotein binding properties. Ox-LDL stimulated glycosaminoglycan synthesis, as measured by (35)SO(4) incorporation, by 30-50% over that of native LDL. The effect was maximal after 72 h of exposure to 5 microg/ml of Ox-LDL. The molecular sizes of versican, biglycan, and decorin increased in response to Ox-LDL, as indicated by size exclusion chromatography and SDS-polyacrylamide gel electrophoresis. These effects could be mimicked by the lipid extract of Ox-LDL. These size increases were largely due to chain elongation and not to alterations in the ratio of (35)SO(4) to [(3)H]glucosamine incorporation. Affinity chromatography indicated that Ox-LDL stimulated the synthesis of proteoglycans with high affinity for native LDL. Ox-LDL also specifically stimulated mRNA expression for biglycan (but not versican or decorin), which was correlated with increased expression of secreted biglycan. Thus, Ox-LDL may influence lipoprotein retention by regulating synthesis of biglycan and also by altering glycosaminoglycan synthesis of vascular proteoglycans so as to enhance lipoprotein binding properties.

Recruitment of a heparan sulfate subunit to the interleukin-1 receptor complex. Regulation by fibronectin attachment.

In this study, we identified an adhesion-regulated subunit of the interleukin-1 (IL-1) receptor complex. Transfection of fibroblasts with an IL-1 receptor-EGFP construct showed that the fusion protein was located at focal adhesions in cells attaching to fibronectin. Fibronectin attachment caused enhancement in endogenous IL-1 type I receptor levels from on average 2500 to 4300 receptors/cell. In addition, matrix attachment resulted in a decrease in binding affinity (Ka) from 1.0 x 10(9) (M-1) to 5.6 x 10(8) (M-1), due to a 2-fold reduction in association rate constant. The adhesion-mediated effects were reversed by soluble heparin. Cross-linking experiments showed that in cells attached to fibronectin, 50-70% of the radiolabeled IL-1 was associated with a heparinase sensitive, high molecular mass component of about 300 kDa, with a core protein of 80-90 kDa. Formation of the complex was dependent on cell interaction with the heparin binding region in fibronectin and required IL-1/type I IL-1 receptor binding. This report demonstrates the recruitment of a heparan sulfate to the IL-1 receptor complex, following attachment to fibronectin, which correlates with alterations in receptor function. The data suggest that the heparan sulfate constitutes an attachment regulated component of the IL-1 receptor complex with the role of mediating matrix regulation of IL-1 responses.

Human monocyte-derived macrophages secrete two forms of proteoglycan-macrophage colony-stimulating factor that differ in their ability to bind low density lipoproteins.

This study evaluated whether human monocyte-derived macrophages synthesize specific types of proteoglycans with lipoprotein-binding capability that could contribute to lipid retention in the arterial wall. After labeling with either [35S]SO4 or [35S]methionine, macrophages secreted a high molecular mass proteoglycan, with glycosaminoglycan chains of approximately 18 kDa and core protein bands of approximately 100 and 55 kDa. Both core protein bands were recognized by an antibody to PG-100, an antibody that recognizes the proteoglycan form of macrophage colony-stimulating factor (PG-100/PG-MCSF). The interaction between PG-100/PG-MCSF and low density lipoproteins (LDL) was examined by gel mobility shift. In this system, PG-100/PG-MCSF was resolved further into two forms. The two forms had the same core proteins but differed in their overall size and glycosaminoglycan content. The larger form contained glycosaminoglycan chains that were entirely chondroitin ABC lyase-sensitive, whereas the smaller form contained chains that were sensitive to both chondroitin ABC lyase and heparinase. Both forms bound native LDL with high affinity, but the larger form bound LDL with higher affinity than the smaller form. The glycosaminoglycan chains of PG-100/PG-MCSF, but not the core proteins, were responsible for binding to native LDL. Mildly oxidized LDL and methyl-LDL, which have an electrophoretic charge similar to that of native LDL, also bound PG-100/PG-MCSF. In contrast, extensively oxidized LDL and acetyl-LDL, which are more electronegative than native LDL, did not bind to either form of PG-100/PG-MCSF. The demonstration of two forms of human monocyte-derived macrophage PG-100/PG-MCSF which bind LDL may represent an additional role for macrophages in the extracellular trapping of lipoproteins in atherosclerosis.

Selective expression and processing of biglycan during migration of bovine aortic endothelial cells. The role of endogenous basic fibroblast growth factor.

Repair of the vascular lumenal surface after injury requires a controlled endothelial cell response that includes cell migration, proliferation, and remodeling of the extracellular matrix. These cellular processes are modulated by growth factors that are released or activated following cell injury. When endothelial cell migration is stimulated in response to monolayer wounding in vitro, cells increase synthesis of small leucine-rich dermatan sulfate proteoglycans (PGs) (Kinsella, M. G., and Wight, T. N. (1986) J. Cell Biol. 102, 679-687). However, the identity of the PGs that are increased during cell migration and the factors that affect this modulation have not been identified. We now report that basic fibroblast growth factor (bFGF) is responsible for the transient increase of [35S]sulfate incorporation into PGs following monolayer wounding. SDS-polyacrylamide gel electrophoresis analysis revealed that bFGF-treated and wounded cultures increase both biglycan core protein synthesis and biglycan proteolytic processing, which results in the accumulation of a approximately 20-kDa N-terminal biglycan fragment in the culture media. Biglycan RNA steady-state levels also selectively increase 2- to 3-fold after wounding or bFGF treatment. Finally, immunocytochemical staining localizes biglycan to the tips and edges of lamellopodia on migrating cells, indicating that biglycan is found at loci at which the formation and dissolution of adhesion plaques occurs, consistent with hypotheses that predict involvement of biglycan in the control of cell migration. Taken together, these results suggest that release of endogenous bFGF is primarily responsible for altered biglycan expression, synthesis, and proteolytic processing as endothelial cells migrate after wounding.

Combinatorial biosynthesis of 'unnatural' natural products: the polyketide example.

Multi-enzyme systems, such as those involved in the biosynthesis of polyketides, typically catalyze several distinct reactions that are combined in different ways to generate diverse natural products. The variability available in such systems has not been fully harnessed from nature. It may therefore be possible to create 'unnatural' natural products, which may be as structurally diverse and medicinally valuable as existing natural products, using combinatorial biosynthesis.

Freehand technique to harvest partial-thickness skin to repair superficial facial defects.

BACKGROUND: The freehand-scalpel technique to harvest skin for grafting is a forgotten surgical art. Modern facial surgeons prefer to use local skin flaps or Wolfe-type full grafts to repair facial defects. OBJECTIVE: To determine the relative merits and cosmetic results of freehand skin grafts to cover facial defects following Mohs surgery. METHODS: We used the freehand-scalpel technique to harvest skin from the periauricular region of the neck and cheek, and other sites. After a local anesthetic is injected the number 15 or 10 blade is used to harvest skin by sequential tangential incisions. The average dermal thickness was about 1.0 mm. To improve cosmetic appearance, the overall shape and thickness of the graft was contoured during harvesting to fit cosmetic unit or facial line. RESULTS: For more than 5 years we have used the freehand technique to repair superficial facial defects of the nose, ear, scalp, temple, forehead, and other nonhead sites. A total of 65 freehand procedures were performed to repair facial defects. The distribution of the anatomic sites and sizes are presented. The size ranged from less than 1 cm to greater than 5 cm in diameter. Three typical cases are presented to illustrate the gratifying results that can be obtained with this technique. CONCLUSIONS: In selected sites and patients, the freehand graft is a rapid and convenient method of harvesting skin. When harvested from the preauricular cheek and subauricular neck, the graft is a good match to cover sun-exposed defects of the nose and ear. The major advantages of the freehand technique are that: 1) it expands the number of potential donor sites from which to select the most compatible skin to cover facial defects; 2) it allows the surgeon to efficiently configure the graft to the desired shape and depth to conform to the cosmetic unit or defect that is being reconstructed; 3) it does not require a dermatome or other specialized instrument to perform; and 4) it achieves wound repair with good appearance and function. The freehand partial-thickness skin graft has become our preferred method of grafting superficial facial defects.

Weight loss and metabolic changes of morbidly obese patients after gastric partitioning operation.

UNLABELLED: Weight loss, alterations in basal metabolic rate, and utilization of body fat, carbohydrate, and protein substrates were studied in nine patients before operation and 3 and 12 months after gastric partitioning operation for morbid obesity. Respiratory oxygen consumption and carbon dioxide excretion measurements were taken three consecutive mornings by the open circuit-Scholander technique. Measurements of urine urea nitrogen were made from 24-hour urine collections. Basal metabolic rate and utilization of fat, carbohydrate, and protein were calculated in kilocalories per minute by indirect calorimetry. Initial body weight was 124.5 +/- 19.0 kg (mean +/- SD). The weight losses between measurements at months 0 and 3 and at months 3 and 12 were 20.8 +/- 4.6 kg and 2.7 +/- 8.4 kg, respectively. Total weight loss between months 0 and 12 was 23.5 +/- 8.3 kg (19.3% +/- 7.4%). At 3 months the fraction of basal metabolic rate contributed by carbohydrate (p less than 0.05) and protein (p less than 0.01) utilization decreased significantly, while that contributed by fat increased (p less than 0.05). Between months 0 and 12 there was no significant difference in protein or carbohydrate utilization, but fat utilization increased (p less than 0.10). CONCLUSIONS: Gastric partitioning operation resulted in an initial rapid body weight loss over 3 months with a sustained reduction over 1 year; there was a metabolic utilization shift to fat with carbohydrate and protein sparing; no metabolic parameter was predictive of weight loss; and temporally, the rapid weight loss was paralleled by a significant metabolic utilization shift, and the sustained loss was paralleled by a stabilization of this shift.

Instrumentation simultaneously measuring VCO2 and VO2 in humans using titration methods.

An instrument has been developed for the simultaneous measurement of carbon dioxide excretion (VCO2) and oxygen uptake (VO2). This instrument, the Nutrimeter, gives these breath-averaged measurements continuously without having to determine respiratory flow rate, perform timed spirometric gas collections, or determine absolute CO2 or O2 concentrations. It can be used on ventilated or nonventilated patients in long- and short-term studies. VO2 is determined via the replenishment technique. VCO2 is determined via a new technique, absorption-titration, described here. Bench test results of VCO2 measurements show a standard error of the estimate (SEE) +/- 0.591% of full scale (500 ml/min) and maximum single point error (MSPE) of +/- 3.54% over a 100--350 ml/min range. VO2 measurements show SEE +/- 0.518% of full scale (1,000 ml/min) and MSPE +/- 2.42% over a 100--450 ml/min range. In 31 human clinical trials the Nutrimeter was compared with the open-circuit spirometric collection and micro-Scholander analysis technique. VCO2 measurements show SEE +/- 2.208% and MSPE +/- 10.57% over 135--315 ml/min. VO2 measurements show SEE +/- 1.134% of full scale and MSPE +/- 9.54% over 170--360 ml/min. Response time is 60 s optimally for step changes in VO2 (0--90% of steady-state value), 90 s for VCO2.