Rates of Borrelia burgdorferi infection in Ixodes dammini (Acari: Ixodidae) in southwestern Wisconsin.

Ixodes dammini Spielman, Clifford, Piesman & Corwin collected from a study site in southwestern Wisconsin were examined for Borrelia burgdorferi infection. Adult spirochete infection rates varied seasonally (38.1%, spring 1990; 60.3%, fall 1990; 41.2%, spring 1991) and were similar to or higher than rates reported in various studies from the northeastern United States. Statistical comparison of seasonal infection rates indicated a significant difference between the fall 1990 adult population and the subsequent overwintered population of the same cohort (spring 1991). Additionally, a significant decrease in the intensity of spirochete infection was observed in the overwintered adult sample.     

Advances in treatment of type II diabetes mellitus in the elderly.

Elderly diabetic patients are prone to the acute and subacute consequences of hyperglycemia, which can adversely affect health, well being, and quality of life. Every elderly patient with diabetes should be offered an individualized treatment plan, consisting of education, dietary counseling, and an exercise program. If fasting and postprandial glucose levels do not stay consistently in the desired range, then an oral hypoglycemic agent should be instituted at the lowest possible dose. When the oral hypoglycemic agent fails, it may be possible to achieve good glycemic control with the addition of insulin. Recent developments in insulin administration can optimize glycemic benefits and reduce potential adverse effects.     

Effects of beta-adrenergic blockade on nitroglycerin-induced augmentation of regional coronary blood flow in patients

Although beta-adrenergic blockade may increase coronary vascular resistance in some patients with severe ischemic heart disease, the effects of beta blockade on the nitroglycerin (NTG)-induced augmentation of coronary blood flow have not been elucidated. Therefore, systemic hemodynamic and anterior left ventricular regional coronary blood-flow (thermodilution) data were measured during administration of NTG into the left coronary artery, before and 10 min after intravenous propranolol (0.1 mg/kg) in 22 patients. Six patients (Group 1) had normal left coronary arteries and nine (Group 2) had severe coronary artery disease with at least greater than 70% narrowing of the left anterior descending artery. In seven additional patients (three without and four with greater than 70% left anterior descending coronary artery disease), measurements were obtained with constant-paced heart rates (Group 3). Before beta blockade, NTG (200 mcg) significantly increased anterior regional great-vein flow [for Group 1, 84 +/- 38% (81 +/- 20 to 140 +/- 60 ml/min); Group 2, 39 +/- 41% (61 +/- 26 to 83 +/- 38 ml/min); and Group 3, 87 +/- 55% (75 +/- 36 to 144 +/- 86 ml/min)]. In Groups 1 and 2, beta-adrenergic blockade reduced heart rate 10% (p less than 0.01) but did not affect mean arterial or pulmonary artery pressures.(ABSTRACT TRUNCATED AT 250 WORDS)     

Renal Effects of Multiple Infusion of Pyridoxalated-Hemoglobin-Polyoxyethylene Conjugate (PHP) Solution in Dogs

Abstract: Pyridoxalated-hemoglobin-polyoxyethylene conjugate (PHP), which is made from out-dated human red blood cells by two major chemical modifications, namely pyridoxalation and conjugation with polyoxyethylene (POE), is currently under development as a physiological oxygen carrier. This study assessed the effects of PHP-88 solution, which contains 8% (wt/vol) each of hemoglobin (Hb) and maltose, on renal function when it was infused 3 times every other day into the intact circulation of 8 dogs (5 dogs for the PHP group and 3 for the control group; 20 ml/kg for the first infusion, and 10 ml/kg each for the second and third infusions, at the rate of 2.5 ml/h/kg). Serial determinations of glomerular filtration rate (GFR) and renal plasma flow (RPF) were carried out pre- and postinfusion for up to 3 months along with measurements of blood and urine analyses, urine output rate, fractional excretion of sodium (FES), and free water clearance (C_H2O). The results showed that plasma colloid osmotic pressure (COP) elevated an average of 3.3 mm Hg (p = 0.0085), and GFR and RPF tended to increase by 13% (NS) and 38% (NS), respectively, immediately after the third infusion with PHP solution. Urine output rate increased during and after the infusion, and FES and C_H2O also increased for 24 h after the infusion in both groups. Blood urea nitrogen, serum creatinine, and serum Na⁺ concentrations were not affected greatly by the infusions, but hematocrit was decreased by 8% in the PHP group, indicating approximately a 42% expansion of plasma volume. These changes were observed to return to their preinfusion levels by 1 week postinfusion. Renal histology of the PHP group obtained at 2 weeks postinfusion revealed vacuole formation in the proximal tubules which was not associated with any pathologic changes indicative of cell death or regeneration. In 4 out of 5 dogs at 3 months postinfusion (necropsy), the vacuoles were not present. Though urinary N-acetyl β-glucosaminidase (NAG) activity had significantly increased after infusion, it returned to the preinfusion level by 1 month postinfusion. No detrimental effect of vacuoles on the assessed renal tubular functions was confirmed in the present study. The result demonstrated that multiple infusions of PHP solutions were well tolerated in normal dogs, and the observed effects were conceived predominantly attributable to the physiological response of the kidneys to an oncotic load into the circulation, which produced plasma volume expansion.     

Aberrant expression of tight junction-related proteins ZO-1, claudin-1 and occludin in synovial sarcoma: an immunohistochemical study with ultrastructural correlation.

Synovial sarcoma demonstrates epithelial differentiation, either by light microscopy (biphasic synovial sarcoma) or by immunohistochemical/ultrastructural methods only (monophasic) and poorly differentiated synovial sarcoma. Although the glands of synovial sarcoma are known to have tight junction-like structures, far less is known about junction formation in the spindled component of synovial sarcomas. Additionally, it is unknown whether the tight junctions of synovial sarcoma are normally constituted. The tight junction is a multiprotein complex consisting of numerous proteins that include ZO-1, claudin-1 and occludin. A total of 35 cases of synovial sarcoma (13 biphasic, 14 monophasic and eight poorly differentiated) were immunostained for ZO-1, claudin-1 and occludin using commercially available antibodies, heat-induced epitope retrieval and standard avidin-biotin technique. When available, corresponding electron micrographs were reviewed. For five cases, the presence of either an SYT-SSX1 (three cases) or SYT-SSX2 (two cases) gene fusion was known. Positive cases showed particulate membrane staining. The glands of biphasic synovial sarcomas expressed ZO-1 (13/13), claudin-1 (12/13) and occludin (11/13) in a manner identical to normal glandular epithelia, at the apical portion of the lateral membrane. The spindle cells of biphasic synovial sarcomas showed abnormal circumferential membranous expression of ZO-1 (12/13), claudin-1 (6/13) and occludin (3/13). Monophasic synovial sarcomas expressed ZO-1 in a circumferential pattern (13/14) but less often claudin-1 (4/14) or occludin (3/14). Poorly differentiated synovial sarcomas expressed ZO-1 (8/8) and claudin-1 (6/8) but only rarely occludin (2/8). By electron microscopy, recognizable tight junctions were seen only in glands. No correlation was seen between histologic subtype or fusion type and expression of tight junction proteins. We conclude that the glands of biphasic synovial sarcomas show well-organized, true epithelial tight junctions. In contrast, the spindled cells of all synovial sarcomas show significant abnormalities in the expression and localization of tight junction proteins, suggesting partial and/or aberrant epithelial differentiation.     

Beta-adrenergic blockers reduce the risk of fracture partly by increasing bone mineral density: Geelong Osteoporosis Study.

This population-based study documented beta-blocker use in 59/569 cases with incident fracture and 112/775 controls. OR for fracture associated with beta-blocker use was 0.68 (95%CI, 0.49-0.96). Beta-blockers were associated with higher BMD at the total hip (2.5%) and UD forearm (3.6%) after adjusting for age, anthropometry, and thiazide use. Beta-blocker use is associated with reduced fracture risk and higher BMD. INTRODUCTION: Animal data suggests that bone formation is under beta-adrenergic control and that beta-blockers stimulate bone formation and/or inhibit bone resorption. MATERIALS AND METHODS: We evaluated the association between beta-blocker use, bone mineral density (BMD), and fracture risk in a population-based study in Geelong, a southeastern Australian city with a single teaching hospital and two radiological centers providing complete fracture ascertainment for the region. Beta-blocker use was documented for 569 women with radiologically confirmed incident fractures and 775 controls without incident fracture. Medication use and lifestyle factors were documented by questionnaire. RESULTS: Odds ratio for fracture associated with beta-blocker use was 0.68 (95% CI, 0.49-0.96) for any fracture. Adjusting for age, weight, medications, and lifestyle factors had little effect on the odds ratio. Beta-blocker use was associated with a higher BMD at the total hip (2.5%, p = 0.03) and ultradistal forearm (3.6%, p = 0.04) after adjustment for age, anthropometry, and thiazide use. CONCLUSION: Beta-blockers are associated with a reduction in fracture risk and higher BMD.     

Chronic Fatigue: A Survey, Outcome Study and Proposals

Background:  Sample sizes in studies of childhood chronic fatigue remain small and there is a need to integrate research findings and establish common criteria.
Method:  This is a detailed report of 20 children with medically unexplained fatigue, referred to as Chronic Fatigue Syndrome (CFS). It includes an uncontrolled outcome study of treatment based on a pragmatic cognitive-behavioural model adapted for children at Great Ormond Street Hospital for Children.
Results:  The data revealed psychological distress at 30 times the prevalence found in the normal child population, with specific high-ranking symptoms, including headache, social withdrawal and decreased appetite. Onset tended to occur at 11 years of age with some earlier problems at school age, suggesting it might be possible to identify those most at risk. Follow-up demonstrated improvement in 87% of the sample (parental report), a significant increase in school attendance and a significant decrease in symptom severity. Factors associated with good outcome were short duration of fatigue (less than a year) and behaviours that tended to combat the cycle of avoidance, such as carefully planned home-tuition.
Conclusions:  Recording a comprehensive range of symptoms and factors facilitates comparisons within and between child studies. It is proposed that symptom severity is a particularly relevant measure for Chronic Fatigue Syndrome which is characterised by persisting symptoms.     

Coordinated diagnostic approach for adult obstructive lung disease in primary care.

AIMS: To present an age-stratified approach to the diagnosis of obstructive lung disease based on asthma and COPD guidelines and epidemiology. METHODS: Asthma guidelines emphasize the role of the history and physical examination, with pulmonary function used primarily to confirm the diagnosis. COPD guidelines begin with symptoms and risk exposure, presenting spirometry as the primary diagnostic maneuver. Data from the National Health Interview Survey and the Third National Health and Nutrition Examination Survey illustrate relationships in prevalence of asthma and COPD in nationally representative samples. RESULTS: Asthma prevalence in adults declines with age from 5-10% at age 20-40 to 4-8% above age 60. COPD is uncommon in adults under age 40 but increases with age, surpassing asthma in older adults. CONCLUSIONS: These trends suggest that asthma screening is most useful in adults up to age 40, after which COPD screening and differential diagnosis are of comparable or greater utility.