Spray application of Bacillus thuringiensis israelensis (Bti strain AM65-52) against Aedes aegypti (L.) and Ae. albopictus Skuse populations and impact on dengue transmission in a dengue endemic residential site in Malaysia.

A one year study was conducted to evaluate the impact of spray application of Bacillus thuringiensis israelensis (Bti), strain AM65-52 on vector populations and dengue transmission in a dengue endemic state in Malaysia. Residential sites with similar populations of Aedes aegypti (L.) and Aedes albopictus Skuse were studied. One site was treated with spray application of Bti into all outdoor target vector habitats, which consisted of natural and artificial containers. The other site was not treated. The impact of spray application was measured with an indoor and outdoor ovitrap index (OI) and epidemiologic data. Significant reductions in both Ae. aegypti and Ae. albopictus, OI were observed both indoors and outdoors, in treated sites compared to untreated sites (p < 0.05). OI reduction was achieved over time in the treated area. The OI was suppressed to below 10%. This was maintained for 4 weeks into the post-treatment phase. The outdoor OI at the untreated site remained at more than 40% for 38 weeks during the evaluation period. One dengue case occurred at the Bti treatment site at the beginning of the treatment phase, but no further cases were detected during the remainder of the treatment phase. However, there was an ongoing dengue outbreak in the untreated area with 15 serologically confirmed cases during weeks 37-54. Intensive fogging operations with pyrethroids at the untreated (Bti) site had a positive impact on Ae. albopictus, but not on Ae. aegypti.

Characterization of the inflammatory cell infiltrate in herald patches and fully developed eruptions of pityriasis rosea.

BACKGROUND: Pityriasis rosea (PR) is a common cutaneous papulosquamous disorder affecting young adults. Previous studies have suggested possibilities of a viral aetiology and the involvement of cell-mediated immunity, but these remain unproven to date. AIM: To elucidate the possible pathomechanisms in PR by characterizing the inflammatory cellular infiltrate in herald patches and fully developed PR eruptions. METHODS: In total, 12 biopsy specimens from 6 patients diagnosed with PR were examined. For each patient, biopsies were taken from both a herald patch and a secondary patch. Specimens were processed for histopathological examination and immunohistochemical staining with a large panel of monoclonal antibodies. RESULTS: Histopathologically, all specimens showed epidermal changes such as parakeratosis, orthokeratosis, epidermal hyperplasia and spongiosis. Less common results included epidermal exocytosis and focal parakeratosis. In all biopsies, the dermal infiltrate of lymphocytes stained positively for monoclonal antibodies specific for T cells. The ratio of the CD4+ (helper) vs. CD8+ (cytotoxic) T cells in the dermal infiltrate was increased in most specimens. Increased staining for Langerhans cells was seen within the dermis of lesional skin. There were no marked differences found in histopathology and immunohistochemistry between the herald patch and secondary lesions. Overall, there was a lack of natural killer cell and B-cell activities in PR lesions. CONCLUSIONS: Our results support a predominantly T-cell mediated immunity in the development of PR.

Period prevalence and mortality rates associated with hypocholesterolaemia in dogs and cats: 1,375 cases.

To determine the period prevalence of hypocholesterolaemia and the associated mortality rates in dogs and cats at a university teaching hospital. The secondary aim was to identify disease processes associated with hypocholesterolaemia. MATERIALS AND METHODS: Medical records over a 5-year period were reviewed to determine the severity of hypocholesterolaemia and its associated mortality rate. Medical records of animals with moderate to severe hypocholesterolaemia (<2.59 mmol/L in dogs, <1.81 mmol/L in cats) were analysed further. Animals with hospital-acquired hypocholesterolaemia were identified. RESULTS: Among 16,977 dogs and 3,788 cats that had at least one cholesterol measurement, the period prevalence of hypocholesterolaemia was 7.0% in dogs and 4.7% in cats. The mortality rate of hypocholesteraemic dogs and cats was 12% in both species which was significantly higher than that of animals with normal serum cholesterol. The degree of hypocholesterolaemia was significantly associated with mortality. Dogs, but not cats, with hospital-acquired hypocholesterolaemia had a higher mortality rate than those presenting with hypocholesterolaemia. Disease of hepatic, gastrointestinal and lymphoreticular systems were most commonly associated with hypocholesterolaemia, and infectious and neoplastic disease were the most commonly associated pathophysiologic processes in both species. Lymphoma was over-represented in dogs with neoplasia. CLINICAL SIGNIFICANCE: Hypocholesterolaemia is not a frequent abnormality but was associated with mortality in this study and may be a negative prognostic indicator. It is not known if hypocholesterolaemia is simply a marker for disease severity, or if it is has active physiologic effects contributing to poor outcomes.

Enhanced expression of interferon-inducible protein-10 correlates with disease activity and clinical manifestations in systemic lupus erythematosus.

Our objective was to investigate the serum levels of interferon-inducible protein-10 (IP-10) in systemic lupus erythematosus (SLE) and their correlation with disease activity and organ manifestations. Serum IP-10 levels were assessed in 464 SLE patients and 50 healthy donors. Disease activity was assessed by the revised SLE Activity Measure, and the concomitant active organ manifestations, anti-ds DNA antibody titres, complement levels and erythrocyte sedimentation rates recorded. Peripheral blood mononuclear cell (PBMC) synthesis of IP-10 in SLE patients and controls was determined by in vitro cultures stimulated with mitogen or lipopolysaccharide. Elevated serum IP-10 levels were observed in SLE patients, which were significantly higher in the presence of active haematological and mucocutaneous manifestations. SLE PBMCs exhibited enhanced spontaneous IP-10 production in vitro. Serial IP-10 levels correlated with longitudinal change in SLE activity, even at low levels where anti-dsDNA antibody and complement levels remain unchanged. These data demonstrate that IP-10 levels are increased in SLE and serum IP-10 may represent a more sensitive marker for monitoring disease activity than standard serological tests.

Drug interactions in dermatological practice.

Systemic drugs are increasingly used in the treatment of dermatological diseases. Due to the high prevalence of polypharmacy, dermatologists are increasingly faced with the complex problem of drug interaction. Unlike adverse drug reactions, which are often unpredictable, drug interactions can be avoided. This article presents the significant drug interactions that are encountered in clinical practice, with the interactions categorized into those involving antimicrobials, immunosuppressants, antimalarials and colchicine, retinoids and psychiatric medications. There are few commonly used drugs that often cause drug interactions. These include ciclosporin, azole antifungal drugs, erythromycin, sulfonamides and rifampicin, and dermatologists should be alert whenever encountering them. A section on interactions of drugs with health supplements, herbs and food is also included, in view of the increasing use of alternative and complementary therapies in many parts of the world.

Distinguishing fall activities from normal activities by angular rate characteristics and high-speed camera characterization.

Distinguishing sideways and backward falls from normal activities of daily living using angular rate sensors (gyroscopes) was explored in this paper. Gyroscopes were secured on a shirt at the positions of sternum (S), front of the waist (FW) and right underarm (RU) to measure angular rate in lateral and sagittal planes of the body during falls and normal activities. Moreover, the motions of the fall incidents were captured by a high-speed camera at a frame rate of 250 frames per second (fps) to study the body configuration during fall. The high-speed camera and the sensor data capture system were activated simultaneously to synchronize the picture frame of high-speed camera and the sensor data. The threshold level for each sensor was set to distinguish fall activities from normal activities. Lead time of fall activities (time after threshold value is surpassed to the time when the hip hits the ground) and relative angle of body configuration (angle beta between the vertical line and the line from the center point of the foot or the center point between the two legs to that of the waist) at the threshold level were studied. For sideways falls, lead times of sensors at positions FW and S were about 200-220ms and 135-182ms, respectively. The lead time of the slippery backward fall (about 98ms) from the sensor at position RU was shorter than that of the sideways falls from the sensors at positions FW and S. The relative angle of body configuration at threshold level for sideways and backward falls were about 40-43 degrees for the sensor at position FW, about 43-52 degrees for the sensor at position S and about 54 degrees for the sensor at position RU, respectively. This is the first study that investigates fall dynamics in detection of fall before the person hits the ground using angular rate sensors (gyroscopes).

A simplified method for the preparation of pure UDP[14C] glucose.

A two-step enzymatic synthesis of UDP[14C] glucose was described which resulted in high yield. Separation of product from labelled intermediates and other contaminants was achieved by a simple ion exchange chromatography method.

Evidence for the non-identity of proteins having synthase phosphatase, phosphorylase phosphatase and histone phosphatase activity in rat liver.

Synthase phosphatase, phosphorylase phosphatase and histone phosphatase in rat liver were measured using as substrates purified liver synthase D, phosphorylase alpha and 32P-labelled phosphorylated f1 histone, respectively. The three phosphatase enzymes had different sedimentation characteristics. Both synthase phosphatase and phosphorylase phosphatase were found to sediment with the microsomal fraction under our experimental conditions. Only 10% of histone phosphatase was in this fraction; the majority was in the cytosol. No change in histone phosphatase was observed in the adrenalectomized fasted rat whereas synthase phosphatase and phosphorylase phosphatase activities were decreased 5-10 fold. Fractionation of liver extract with ethanol produced a dissociation of the three phosphatase activities. When a partially purified fraction was put on a DEAE-cellulose column, synthase phosphatase and phosphorylase phosphatase both exhibited broad elution profiles but their activity peaks did not coincide. Histone phosphatase eluted as a single discrete peak. When the supernatant of CaCl2-treated microsomal fraction was put on a Sepharose 4B column, the majority of synthase phosphatase was found to elute with the larger molecular weight proteins whereas the majority of phosphorylase phosphatase eluted with the smaller species. Histone phosphatase migrated as a single peak and was of intermediate size. Synthase phosphorylase phosphatase by synthase D (Ki approximately 2 units/ml). The inhibition of synthase phosphatase by phosphorylase alpha was kinetically non-competitive with substrate. Histone phosphatase activity was not inhibited by synthase D or by phosphorylase alpha. The above results suggest that different proteins are involved in the dephosphorylation of synthase D, phosphorylase alpha and histone in the cell.

Regulation of synthase phosphatase and phosphorylase phosphatase in rat liver.

Using substrates purified from liver, the apparent Km values of synthase phosphatase ([UDPglucose--glycogen glucosyltransferase-D]phosphohydrolase, EC 3.1.3.42) and phosphorylase phosphatase (phosphorylase a phosphohydrolase, EC 3.1.3.17) were found to be 0.7 and 60 units/ml respectively. The maximal velocity of phosphorylase phosphatase was more than a 100 times that of synthase phosphatase. In adrenalectomized, fasted animals there was a complete loss of synthase phosphatase but only a slight decrease in phosphorylase phosphatase when activity was measured using endogenous substrates in a concentrated liver extract. When assayed under optimal conditions with purified substrates, both activities were present but had decreased to very low levels. Mixing experiments indicated that synthase D present in the extract of adrenalectomized fasted animals was altered such that it was no longer a substrate for synthase phosphatase from normal rats. Phosphorylase a substrate on the other hand was unaltered and readily converted. When glucose was given in vivo, no change in percent of synthase in the I form was seen in adrenalectomized rats but the percent of phosphorylase in the a form was reduced. Precipitation of protein from an extract of normal fed rats with ethanol produced a large activation of phosphorylase phosphatase activity with no corresponding increase in synthase phosphatase activity. Despite the low phosphorylase phosphatase present in extracts of adrenalectomized fasted animals, ethanol precipitation increased activity to the same high level as obtained in the normal fed rats. Synthase phosphatase and phosphorylase phosphatase activities were also decreased in normal fasted, diabetic fed and fasted, and adrenalectomized fed rats. Both enzymes recovered in the same manner temporally after oral glucose administration to adrenalectomized, fasted rats. These results suggest an integrated regulatory mechanism for the two phosphatase.

Characteristics of the dephosphorylated form of phosphorylase purified from rat liver and measurement of its activity in crude liver preparations.

The phosphorylated form of liver glycogen phosphorylase (alpha-1,4-glucan : orthophosphate alpha-glucosyl-transferase, EC 2.4.1.1) (phosphorylase a) is active and easily measured while the dephosphorylated form (phosphorylase b), in contrast to the muscle enzyme, has been reported to be essentially inactive even in the presence of AMP. We have purified both forms of phosphorylase from rat liver and studied the characteristics of each. Phosphorylase b activity can be measured with our assay conditions. The phosphorylase b we obtained was stimulated by high concentrations of sulfate, and was a substrate for muscle phosphorylase kinase whereas phosphorylase a was inhibited by sulfate, and was a substrate for liver phosphorylase phosphatase. Substrate binding to phosphorylase b was poor (KM glycogen = 2.5 mM, glucose-1-P = 250 mM) compared to phosphorylase a (KM glycogen = 1.8 mM, KM glucose-1-P = 0.7 mM). Liver phosphorylase b was active in the absence of AMP. However, AMP lowered the KM for glucose-1-P to 80 mM for purified phosphorylase b and to 60 mM for the enzyme in crude extract (Ka = 0.5 mM). Using appropriate substrate, buffer and AMP concentrations, assay conditions have been developed which allow determination of phosphorylase a and 90% of the phosphorylase b activity in liver extracts. Interconversion of the two forms can be demonstrated in vivo (under acute stimulation) and in vitro with little change in total activity. A decrease in total phosphorylase activity has been observed after prolonged starvation and in diabetes.

Characterization of the glycogen synthase D found in liver of the adrenalectomized fasted rats.

We have previously shown that the synthase D (UDPglucose:glycogen 4-alpha-D-glucosyltransferase, EC 1.4.1.11) present in the liver of the adrenalectomized fasted rat was not converted to synthase I by synthase phosphatase from normal animals, suggesting the presence of a non-substrate form of synthase D (Tan, A.W.H. and Nuttall, F.Q. (1976) Biochim. Biophys. Acta 445, 118--130). The enzymatic properties of this synthase D have now been examined. Using optimal assay conditions, the total amount of synthase D activity in the adrenalectomized fasted rats was similar to that of normal fed rats when 1% glycogen was included in the homogenizing buffer. However, the two enzymes appeared to have different affinities for the substrate, UDPglucose and the modifier, glucose-6-P. The changes in kinetic properties were not due to differences in glycogen or to a dialyzable modifier in the extracts. Synthase D from adrenalectomized fasted and from normal fed rats was partially purified. After DEAE-cellulose chromatography, modification appeared to have occurred such that the enzyme from the adrenalectomized fasted rat had properties similar to that of the normal fed rat. The enzymes were cold-labile, had different properties from enzymes in the crude extract and they were both converted to synthase I by synthase phosphatase. We conclude from these studies that the phosphorylation site in the synthase is in a flexible region of the protein. Changes in the ability of the synthase D to interact and be dephosphorylated by synthase phosphatase can occur readily in vivo and in vitro. The molecular basis for the modification remains unknown.

Experience with ARRAY multifocal lenses in a Singapore population.

INTRODUCTION: To evaluate the clinical efficiency, safety and subjective visual outcomes of multifocal intraocular lenses (IOL) in the Singapore population. METHODS: This is a retrospective case series of 45 phacoemulsification with multifocal lens implantation performed in 27 patients for cataracts, over a two-year period. The efficacy, stability and safety of the lens were assessed up to six months of follow-up. A telephone interview enquiring about ratings of vision, spectacle independence, glare, driving difficulty and photic phenomena, was conducted and the results were compared with those published in the literature. RESULTS: The best corrected distance Logmar acuity was 0.1 (0.1 and near visual acuity was N5 (range N5 to N8) at six months. The distance visual acuity stabilised by one month whereas near vision remained unchanged from day one post-surgery. Posterior capsular opacification was seen in 17 patients (38.6 percent) of which two patients (4.55 percent) required YAG capsulotomy. Total spectacle independence was achieved in 12 patients (54.4 percent). Among those who required spectacles, 50 percent required spectacles more than 50 percent of the time. Five patients (22.7 percent) reported glare usually at night (80 percent) as compared with daytime glare (20 percent). The most common photic phenomena report after surgery was halo. CONCLUSION: The Advanced Medical Optics ARRAY multifocal IOL showed good efficacy, predictability, stability and safety. The subjective visual outcomes in the Singapore population were comparable to those of their Western counterparts.

Regulation of glycogen synthesis in the liver.

The glycogen synthase-mediated reaction is rate-limiting for glycogen synthesis in the liver. Glycogen synthase has been purified essentially to homogeneity and has been shown to be a dimer composed of identical subunits. It is regulated by a phosphorylation-dephosphorylation mechanism, catalyzed by kinases and a phosphatase. The subunits of synthase D, the most phosphorylated form, each contain approximately 17 phosphates. The subunits of synthase I, the least phosphorylated form, each contain 14 phosphates. Thus, during the transition between these two forms, a net of three phosphoryl groups is added or removed. In synthase D, six of the phosphates are alkali-labile. In synthase I, three of the phosphates are alkali-labile. Therefore, all of the phosphorylation sites important in the interconversion of these two forms are alkali-labile (attached to serine or threonine residues). In short-term experiments using isolated hepatocytes, [32P]phosphate was only incorporated into the alkali-labile sites and the phosphate in these sites was shown to turn over rapidly. Glucose addition, which is known to reduce the proportion of synthase in the D form when assayed kinetically, also reduced the [32P]phosphate content. Glucagon addition, which increases the proportion of synthase in the D form, increased it. These changes do not appear to be site-specific. Ingestion or administration of fructose, or galactose, as well as glucose, result in a shift in synthase equilibrium in favor of the less phosphorylated forms. Possible mechanisms by which synthase phosphatase activity may be increased after ingestion of glucose or fructose, and thus shift the equilibrium in favor of the less phosphorylated forms, are discussed. The mechanism by which galactose may stimulate the phosphatase reaction is completely unknown.

Assessment of hypercholesterolemia control in a managed care organization.

To determine the extent of achievement of goal low-density lipoprotein cholesterol (LDL) as defined by National Cholesterol Education Program-Adult Treatment Panel II (NCEP-ATP 11) and American Diabetes Association (ADA) 2000 guidelines, we conducted a retrospective study by integrating data from medical, laboratory, and pharmacy claims databases. Subjects were selected from a 232,000-member staff-model managed care organization consisting of 19 clinics in the Minneapolis-St. Paul, Minnesota, metropolitan area. A total of 124,971 members aged 18 years and older, who had been continuously enrolled from July 1, 1996-June 6, 1998, were included. Outcome measures were the extent of achievement of goal LDL as defined by NCEP-ATP II and the use of antihyperlipidemic drugs for patients with and without diabetes at various levels of risk for coronary heart disease (CHD). Of 124,971 subjects, 6538 had a history of CHD, 1523 of whom met their LDL goal. Of the population with CHD who did not achieve goal, 1141 (43%) missed by over 30 mg/dl; 621 (54%) of these patients were not receiving drug therapy A total of 17,267 had no history of CHD but had two or more risk factors; 3,298 of these achieved their LDL goal. Of those who did not achieve goal, 1,136 (35%) missed by over 30 mg/dl; 897 (79%) of these were not receiving drug therapy A total of 6,586 had a history of diabetes; 1,004 and 2,340 reached an LDL of 100 mg/dl or lower and less than 130 mg/dl, respectively Of those with diabetes who had an LDL greater than 100 mg/dl, 1,276 (49%) missed their goal by over 30 mg/dl; 898 (70%) of these were not receiving drug therapy. Inadequate use of pharmacologic agents plays a significant role in failure to achieve goal LDL for patients with CHD, without CHD, and with diabetes. Analysis of the data based on the new ADA guidelines for LDL demonstrates the need for continued vigilance. Finally, the successful merging of medical, laboratory, and pharmacy claims databases provides a benchmark for other institutions.

Obesity, fitness, willingness to communicate and health care costs.

BACKGROUND: Obesity and low levels of physical fitness are independently associated with a variety of diseases and disorders. These conditions are modifiable and affect health care utilization. The degree to which these health risks are modifiable is directly related to the readiness of individuals to change the underlying behaviors. This study analyzes the relationship between health care costs, obesity, physical fitness, and willingness to communicate. In addition, we tested the hypothesis that willingness to communicate is directly associated with an individual's readiness to change behavior. METHODS: Multiple regression was used to estimate the relationship between adverse behavioral health outcomes, willingness to communicate, and annualized health care costs incurred over a period of 33 months before the completion of a health risk assessment survey in an employed population enrolled in a Midwestern managed care organization (N = 8822). RESULTS: High body mass index (BMI), low physical fitness (predicted VO2max), and greater willingness to communicate were directly and significantly (P < 0.05) associated with higher health care costs. Relative to low-risk, annualized health care costs for each of the high-risk factors were 8% higher for BMI (rate ratio, 1.08; 95% confidence interval, 1.01-1.15), 10% higher for low predicted VO2max (rate ratio 1.10, 95% confidence interval, 1.02-1.18), and 22% higher for willingness to communicate (rate ratio, 1.22, 95% confidence interval, 1.14-1.30). The association between these health risks and health care costs was independent of age, sex, age-sex interaction, role-mental and role-physical limitations, and nine chronic conditions. Furthermore, willingness to communicate was directly related to a greater readiness to change behavior. CONCLUSIONS: The prevalence of obesity and low physical fitness is high, and these health risks are directly related to health care costs. Willingness of health plan members to communicate around health improvement opportunities appears greatest among those who incur higher costs, and these patients also have more favorable readiness to change profiles. Effective, proactive population-based health improvement efforts appear to have significant potential for positive economic impact.

Lymphomatoid papulosis associated with recurrent cutaneous T-cell lymphoma.

INTRODUCTION: Lymphomatoid papulosis is a chronic benign disease which may be associated with malignant lymphomas. This case illustrates the relapsing and remitting nature of both lymphomatoid papulosis and its potential of developing cutaneous T-cell lymphoma and narrow-band ultraviolet B (NB-UVB) phototherapy as a new modality of treatment of early-stage mycosis fungoides in these patients. CLINICAL PICTURE: A 44-year-old woman has had recurrent crops of papules and nodules of lymphomatoid papulosis on the limbs for 15 years. Histological features are consistent with the type B lesions of lymphomatoid papulosis. Eight years after the initial onset of these lesions she developed cutaneous T-cell lymphoma (mycosis fungoides). Since then, she has had recurrence of mycosis fungoides following the cessation of phototherapy, but had no evidence of systemic involvement. TREATMENT: The lesions of lymphomatoid papulosis responded to intermittent courses of oral methotrexate. Mycosis fungoides was treated with oral psoralen and ultraviolet A phototherapy with good response. Unfortunately, the lesions relapsed, whenever phototherapy was discontinued. The most recent recurrence of mycosis fungoides was treated with NB-UVB therapy. OUTCOME: The papules of lymphomatoid papulosis continue to appear but she remains free of lesions of mycosis fungoides, 10 months after cessation of NB-UVB therapy. CONCLUSION: Long-term surveillance is essential in all cases of lymphomatoid papulosis as accurate predictors for the development of malignant lymphoma in these individuals are still lacking.

Comparison of completely versus incompletely excised cutaneous squamous cell carcinomas.

INTRODUCTION: This is a retrospective case series of cutaneous squamous cell carcinomas (SCCs) which were incompletely excised in National Skin Centre, Singapore from 1991 to 1995. This study compared the characteristics of completely excised versus incompletely excised cutaneous SCCs. MATERIALS AND METHODS: All patients with histologically confirmed SCCs were traced from computerised medical database and information regarding patient profile, tumour characteristics, surgical treatment and outcome were collated. All patients were recalled for clinical examination and documentation of cure. Completely excised and incompletely excised SCCs were compared with regards to the patient and tumour characteristics. RESULTS: There were 57 patients with 63 SCCs who were treated with surgical excision over the 5-year period. Fifty were recalled for physical examination. There were 30 males and 27 females and their mean age was 83.3 years. All except 1 were Chinese of Fitzpatrick skin type 4. One-third of patients had daily or weekly sun exposure in the past and 21.1% had occupational sun exposure; 3.5% had prior arsenic exposure and 3.5% were previously treated with radiotherapy for other malignancies. The mean duration of SCCs was 18.7 months; 7.9% of patients had multiple SCCs and 15.9% had underlying actinic keratoses. The mean diameter of the tumours was 1.97 cm and nearly half were located on the head and neck. All the SCCs were primary and localised to the skin; 84.1% of them were completely excised with a 4 to 6 mm margin. Incompletely excised SCCs were associated with the male sex, larger tumours and tumours on the genitals and lower limbs. CONCLUSION: In our experience, the tumour clearance rate is 84.1% following conventional excision. Incomplete excision is associated with male sex, larger tumours and those on the genitals and lower limbs.