Who contributes to the public health function?

OBJECTIVES: To describe patterns of hypertension history in patients with various types of end-stage renal disease (ESRD) and in persons with normal kidney function; and to identify risk factors for the diagnosis 'hypertensive ESRD'. DESIGN: A case-control study. SETTING: Population-based. PARTICIPANTS: Patients with ESRD due to hypertension (n = 214), diabetes (n = 239), other specified causes (n = 181), unknown causes (n = 82) and control subjects drawn from the general population (n = 361). MAIN OUTCOME MEASURES: Participants' history of hypertension. RESULTS: The prevalence of hypertension was 90% in ESRD patients and 27% in controls. Only 6% of patients with hypertensive ESRD had a history of malignant hypertension. Patients with hypertensive ESRD were more likely to have been hospitalized because of hypertension (36%) than were other ESRD patients (18%) or controls (5%). ESRD of any cause was more strongly associated with hypertension of > or = 25 years duration (odds ratio 51.0, compared with normal blood pressure) than it was with hypertension of shorter duration (15-25 years: odds ratio 31.8, 5-15 years: odds ratio 16.0, < 5 years: odds ratio 21.2). Among patients who had both hypertension and ESRD, the diagnosis of 'hypertensive ESRD' was associated independently with a long duration of hypertension, greater severity of hypertension, the absence of diabetes, black race, and limited education. CONCLUSIONS: Hypertension is common among patients with ESRD. The risk of ESRD from any cause increases progressively with the duration of hypertension, and with indicators of severe hypertension. This result supports the hypothesis that nonmalignant hypertension of long duration may cause renal insufficiency. The criteria used to diagnose hypertensive ESRD are consistent with pathophysiologic and epidemiologic evidence.     

Flow cytometric method for detecting thiazole orange-positive (reticulated) platelets in thrombocytopenic horses

OBJECTIVE: To evaluate a method for detecting thiazole orange-positive (TO+, reticulated) platelets in equine blood, using flow cytometry. ANIMALS: 16 healthy, equine infectious anemia virus (EIAV)-negative horses and ponies; 9 thrombocytopenic, EIAV-positive horses and ponies; and 2 thrombocytopenic, EIAV-negative horses. PROCEDURE: Blood from healthy and thrombocytopenic horses was collected by jugular venipuncture. Appropriate sample requirement and incubation time for the assay were evaluated, using blood anticoagulated with EDTA or sodium citrate, or platelet-rich plasma in sodium citrate. The sample of blood or platelet-rich plasma was incubated with thiazole orange, and flow cytometric analysis was performed. Percentage of circulating TO+ platelets was determined from fluorescence (FL-1) logarithmic histograms. RESULTS: Healthy ponies (n = 9) had 1.28 to 2.83% (mean +/- SD, 2.03 +/- 0.50%) and horses (n = 7) had 0.9 to 3.44% (2.12 +/- 1.14%) TO+ platelets in circulation. Thrombocytopenic ponies (n = 7) had 11.14 to 48.41% (26.51 +/- 11.99%) and thrombocytopenic horses (n = 4) had 2.33 to 8.52% (6.19 +/- 2.68%) TO+ platelets in circulation. Mean platelet counts for the thrombocytopenic ponies and horses were 24,400 +/- 20,500 and 39,300 +/- 13,500 platelets/microliters, respectively (reference range, 94,000 to 232,000 platelets/ microliters). CONCLUSION: Thiazole orange-positive platelets can be detected in equine blood and percentages of TO+ platelets are increased in thrombocytopenic horses. CLINICAL RELEVANCE: Enumeration of TO+ platelets may prove to be a helpful noninvasive clinical measurement of bone marrow platelet production and aid in the assessment of platelet kinetics in thrombocytopenic horses.     

Acute effects of periarterial sympathectomy on the cutaneous microcirculation

Inoculation of soybean (Glycine max L. cv. Jangyup) hypocotyls with Phytophthora sojae f. sp. glycines results in a marked accumulation of some pathogenesis-related (PR) proteins. A basic beta-1,3-glucanase (34 kDa) was purified from soybean hypocotyls infected by an incompatible race of P. sojae f. sp. glycines using CM-cellulose cation exchange chromatography and Bio-gel P-60 gel filtration. The purified soybean beta-1,3-glucanase cross-reacted with polyclonal antibody raised against a tomato beta-1,3-glucanase. The activity of beta-1,3-glucanase was much higher in the infected soybean hypocotyls than the healthy ones. The beta-1, 3-glucanase purified from soybean inhibited spore germination and hyphal growth of the chitin-negative fungus P. sojae f. sp. glycines, but did not show any antifungal activity against the chitin-containing fungi Alternaria mali, Colletotrichum gloeosporioides, and Magnaporthe grisea.     

Myelinated axon undergoes complete demyelination in the panencephalopathic--but it is merely subjected to the Wallerian degeneration in the polioencephalopathic type of transmissible spongiform encephalopathies

The aim of a cancer registry is to study the incidence of cancer in a well-determined population and to allow epidemiological research to the setting up of diagnosis and therapeutic strategies. The Belgian Thyroid Cancer Study Group (BTCSG) was founded in 1990. In the present study we report data collected from 1988 to 1995 in 397 patients with a differentiated (papillary and follicular) thyroid carcinoma living in the french-speaking area of Belgium. The sex ratio female/male is 3.5 and the median ages at the diagnosis, is similar (45 yrs, 12-82) in both sexes. Seven cases of thyroid cancer were registered in young patients less than 18 yrs old. Thyroid carcinoma were associated with multinodular goiter in more than 50% cases. Cancer was bilateral in 17%. Papillary histological type accounts for 84% in our series while its diagnosis was established in 45% at early clinical stages (TO-T1). These observations could probably be related with 1) broader indications and more aggressive options for the surgical removal of diffuse multinodular goiter, 2) more sophisticated pathologic examinations that might have led to the detection of a greater incidence of occult carcinomas, incidentally discovered. Lymph nodes metastases were present at the time of diagnosis in 20%, especially in young patients. The risk for local and/or lateral recurrence or distant metastases is significantly related to the size of the tumor, histologically verified lymph node metastases and the values of the EORTC prognostic index (> or = 50) that additionally takes into account the differentiation of the tumor. Considering our short median follow-up time of 25 months, it is currently too early to define if the controversial attitude about the extent of surgery (total thyroidectomy plus I131 or individualized surgery) can also negatively influence the risk for recurrence. In our series, eight patients died of thyroid cancer.     

Dietary calcium decreases blood pressure without decreasing renal vascular resistance or altering the response to NO blockade

Many vasoactive elements are involved in the elevation of blood pressure in spontaneously hypertensive rats (SHR). Elevated dietary calcium has been observed to reduce blood pressure in SHR. This study investigates interactions among dietary calcium, renal vascular resistance (RVR), elevation of blood pressure and effects of norepinephrine and nitric oxide synthesis. We completed a series of experiments on two groups each (fed low, 0.1% and high, 2.0% dietary calcium, respectively) of 9-week-old Wistar Kyoto (WKY), 9-week-old and 6-week-old SHR. Although 9-week-old SHR had elevated baseline blood pressure compared to 9-week-old WKY and also compared to 6 week-old SHR, there was no corresponding elevation in baseline RVR. All SHR fed high calcium diets had lower blood pressure compared to low calcium diets, and there was no corresponding reduction in RVR. WKY controls' blood pressure and RVR were unaffected by dietary calcium levels. In all hypertensive rats the blood pressure and renal vascular resistance were elevated by N(G)-nitro-L-arginine methylester (L-NAME), but the dietary differences were sustained. Blood pressure of WKY was unaffected by the low dose of L-NAME. The increase in RVR to L-NAME was greater in SHR than in controls. The renal vascular response to norepinephrine was related to diet in older SHR, but smaller and unrelated to diet in younger SHR. Following L-NAME, WKY had greater responses to norepinephrine than 9-week-old SHR. We conclude that noradrenergic vasoconstriction is enhanced in the adult SHR, especially in the absence of high calcium diet. Alterations in NO synthesis may effect the norepinephrine response.     

Using the Youth Risk Behavior Survey to compare risk behaviors of Texas High School and college students

This study used the Youth Risk Behavior Survey (YRBS) to assess selected health behaviors of Texas high school and college students. The YRBS was administered during 1993 in paper and pencil form to 6,015 high school students representing 329 classrooms from 78 school districts. A total of 1,408 college students representing 23 college and universities were surveyed by telephone in 1993 using a modified version of YRBS. Texas college students reported a higher percentage who had experienced sexual intercourse (82% versus 55.4%), but Texas high school students reported a younger age of first sexual intercourse. High school students also initiated alcohol consumption at a younger age, although college students were more likely to binge drink (33.5% versus 31%). Regular cigarette use also was higher among college students (25.4% versus 19.3%), but was initiated at a younger age by high school students. Study results indicate that health education programs must begin much earlier than during the high school years. Due to early initiation of negative health behaviors, emphasis must be placed on abstinence and risk-reduction techniques for both populations.     

Intracoronary gene transfer of immunosuppressive cytokines to cardiac allografts: method and efficacy of adenovirus-mediated transduction

OBJECTIVE: Allograft-targeted immunosuppressive gene therapy may inhibit recipient immune activation and provide an alternative to systemic immunosuppression. We studied the optimal technique and efficacy of intracoronary gene transfer of viral interleukin-10 and human transforming growth factor-beta 1 in a rabbit model of heterotopic heart transplantation. METHODS: Replication-defective adenoviral vectors were constructed, expressing viral interleukin-10 (AdSvIL10) or transforming growth factor-beta 1 (AdCMVTGF-beta 1). Intracoronary delivery of vectors was accomplished ex vivo by either bolus injection or slow infusion. The allografts were implanted heterotopically in recipient rabbits and collected 4 days after the operation. Vector dose was 4 x 10(9) to 6 x 10(10) pfu/gm of donor heart. Transfer was confirmed by DNA amplification for both genes. Gene product expression in tissue was quantified by immunoassay and visualized by immunohistochemical staining. RESULTS: Allograft viral uptake was only 9.9% +/- 2.4% with bolus injection, but increased to 80.5% +/- 6.8% at 1 ml/min infusion rate (p = 5 x 10(-14)). Uptake ratio was not affected by vector quantity or slower infusion rates. Transforming growth factor-beta 1 was consistently detected in allografts infected with AdCMVTGF-beta 1, but not with control adenovirus or AdSvIL10. Expression was proportional to infused vector quantity and reached 10 ng/gm of allograft at infused 10(10) pfu/gm. Transforming growth factor-beta 1 was also detected in recipient's serum at less than 1 ng/ml. Viral interleukin-10 was detected in minor amounts only (< 1 ng/gm) in allografts infected with AdvIL10 up to 5 x 10(10) pfu/gm. Nevertheless, it was detected in recipient serum at concentrations up to 0.4 ng/ml. CONCLUSIONS: Intracoronary gene transfer of immunosuppressive cytokines to cardiac allografts during cold preservation is feasible. Slow infusion is superior to bolus injection. In vivo effects on allograft rejection remain to be determined.     

Effects of chronic arterial hypertension on constitutive and induced intercellular adhesion molecule-1 expression in vivo

Recent reports indicate that bacterial endotoxin (lipopolysaccharide) and cytokines elicit a more profound increase in the surface expression of intercellular adhesion molecule-1 (ICAM-1) in cultured endothelial cells derived from spontaneously hypertensive (SHR) versus normotensive Wistar-Kyoto rats (WKY). Our objective in this study was to characterize and compare in vivo ICAM-1 expression in SHR and WKY under basal conditions and after 5 hours of endothelial cell activation with either lipopolysaccharide (5 mg/kg i.p.) or tumor necrosis factor-alpha (TNF-alpha; 1, 5, and 10 micrograms/kg i.p.). ICAM-1 expression was quantified in different tissues by the double-radiolabeled monoclonal antibody technique. When constitutive (baseline) ICAM-1 expression was corrected for endothelial cell surface area, significantly higher values were noted in SHR than WKY but only in splanchnic organs. Lipopolysaccharide and TNF-alpha elicited significant increases in ICAM-1 expression in all tissues of both WKY and SHR. However, the magnitude of the lipopolysaccharide-induced ICAM-1 upregulation in heart, stomach, skeletal muscle, and brain was significantly lower in SHR than WKY. A similar blunted ICAM-1 upregulation was noted in the stomach of SHR after administration of 5 micrograms/kg TNF-alpha. The differences in induced ICAM-1 expression between SHR and WKY do not appear to be due to differences in endothelial cell surface area or plasma glucocorticoid levels. These results suggest that chronic arterial hypertension results in altered ICAM-1 expression on the endothelium, which may contribute to the abnormal inflammatory responses associated with this disease.