TGF-β1-induced EMT promotes targeted migration of breast cancer cells through the lymphatic system by the activation of CCR7/CCL21-mediated chemotaxis

Tumor cells frequently disseminate through the lymphatic system during metastatic spread of breast cancer and many other types of cancer. Yet it is not clear how tumor cells make their way into the lymphatic system and how they choose between lymphatic and blood vessels for migration. Here we report that mammary tumor cells undergoing epithelial–mesenchymal transition (EMT) in response to transforming growth factor-β (TGF-β1) become activated for targeted migration through the lymphatic system, similar to dendritic cells (DCs) during inflammation. EMT cells preferentially migrated toward lymphatic vessels compared with blood vessels, both in vivo and in 3D cultures. A mechanism of this targeted migration was traced to the capacity of TGF-β1 to promote CCR7/CCL21-mediated crosstalk between tumor cells and lymphatic endothelial cells. On one hand, TGF-β1 promoted CCR7 expression in EMT cells through p38 MAP kinase-mediated activation of the JunB transcription factor. Blockade of CCR7, or treatment with a p38 MAP kinase inhibitor, reduced lymphatic dissemination of EMT cells in syngeneic mice. On the other hand, TGF-β1 promoted CCL21 expression in lymphatic endothelial cells. CCL21 acted in a paracrine fashion to mediate chemotactic migration of EMT cells toward lymphatic endothelial cells. The results identify TGF-β1-induced EMT as a mechanism, which activates tumor cells for targeted, DC-like migration through the lymphatic system. Furthermore, it suggests that p38 MAP kinase inhibition may be a useful strategy to inhibit EMT and lymphogenic spread of tumor cells.

Effects of hyperbaric pressure on a deep-sea archaebacterium in stainless steel and glass-lined vessels

The effects of hyperbaric helium pressures on the growth and metabolism of the deep-sea isolate ES4 were investigated. In a stainless steel reactor, cell growth was completely inhibited but metabolic gas production was observed. From 85 to 100 degrees C, CO(2) production proceeded two to three times faster at 500 atm (1 atm = 101.29 kPa) than at 8 atm. At 105 degrees C, no CO(2) was produced until the pressure was increased to 500 atm. Hydrogen and H(2)S were also produced biotically but were not quantifiable at pressures above 8 atm because of the high concentration of helium. In a glass-lined vessel, growth occurred but the growth rate was not accelerated by pressure. In most cases at temperatures below 100 degrees C, the growth rate was lower at elevated pressures; at 100 degrees C, the growth rates at 8, 250, and 500 atm were nearly identical. Unlike in the stainless steel vessel, CO(2) production was exponential during growth and continued for only a short time after growth. In addition, relatively little H(2) was produced in the glass-lined vessel, and there was no growth or gas production at 105 degrees C at any pressure. The behavior of ES4 as a function of temperature and pressure was thus very sensitive to the experimental conditions.

Dose-response patterns for vibration-induced white finger

AIMS

To investigate alternative relations between cumulative exposures to hand-transmitted vibration (taking account of vibration magnitude, lifetime exposure duration, and frequency of vibration) and the development of white finger (Raynaud's phenomenon).

METHODS

Three previous studies have been combined to provide a group of 1557 users of powered vibratory tools in seven occupational subgroups: stone grinders, stone carvers, quarry drillers, dockyard caulkers, dockyard boilermakers, dockyard painters, and forest workers. The estimated total operating duration in hours was thus obtained for each subject, for each tool, and for all tools combined. From the vibration magnitudes and exposure durations, seven alternative measurements of cumulative exposure were calculated for each subject, using expressions of the form: dose = summation operator a(m)(i)t(i), where a(i) is the acceleration magnitude on tool i, t(i) is the lifetime exposure duration for tool i, and m = 0, 1, 2, or 4.

RESULTS

For all seven alternative dose measures, an increase in dose was associated with a significant increase in the occurrence of vibration-induced white finger, after adjustment for age and smoking. However, dose measures with high powers of acceleration (m > 1) faired less well than measures in which the weighted or unweighted acceleration, and lifetime exposure duration, were given equal weight (m = 1). Dose determined solely by the lifetime exposure duration (without consideration of the vibration magnitude) gave better predictions than measures with m greater than unity. All measures of dose calculated from the unweighted acceleration gave better predictions than the equivalent dose measures using acceleration frequency-weighted according to current standards.

CONCLUSIONS

Since the total duration of exposure does not discriminate between exposures accumulated over the day and those accumulated over years, a linear relation between vibration magnitude and exposure duration seems appropriate for predicting the occurrence of vibration-induced white finger. Poorer predictions were obtained when the currently recommended frequency weighting was employed than when accelerations at all frequencies were given equal weight. Findings suggest that improvements are possible to both the frequency weighting and the time dependency used to predict the development of vibration-induced white finger in current standards.

Host cell-specific expression of a p44 epitope by the human granulocytic ehrlichiosis agent

The human granulocytic ehrlichiosis agent (HGEa) survives extreme differences between ticks and humans, possibly by use of differential expression of specific antigens for survival in different hosts. The role of the immunodominant p44 antigens is unknown. In this study, HGEa cultured in human or tick cells was probed with human, mouse, and hamster serum and with monoclonal antibodies (MAbs). p44 antigens were strongly expressed in human HL-60 cells but were strikingly reduced in tick cells. In HGEa alternately grown in HL-60 or tick cells, a p44 epitope recognized by MAb R5E4 was expressed in human but not tick cells. This was not a temperature effect, because incubation of infected tick cells at 37 degrees C did not induce expression of the p44 epitope. The p44 antigen predominates in human but not tick cells and may be involved in regulatory changes that mediate survival of the HGEa by immune modulation after tick transmission.

Age- and cause-specific childhood mortality in Lombok, Indonesia, as a factor for determining the appropriateness of introducing Haemophilus influenzae type b and pneumococcal vaccines

Using age and cause-specific childhood mortality in Lombok, Indonesia, as a factor for determining the appropriateness of introducing Haemophilus influenzae type b (Hib) and pneumococcal vaccines, the study describes a cross-sectional, hamlet-level mortality survey in 40 of 305 villages in Lombok Island, Indonesia. Causes of death were assessed with a standardized verbal-autopsy questionnaire. One thousand four hundred ninety-nine births and 141 deaths occurring among children aged less than 2 years were identified, with 43% of deaths occurring during the first 2 months of life. The infant mortality rate was 89 (95% CI: 75, 104) per 1,000 live-births. All mortality rates are reported per 1,000 live-births. To examine children whose deaths could potentially have been prevented through vaccination with Hib or pneumococcal vaccine, deaths due to acute respiratory infection (ARI) and central nervous system (CNS) infections among children, aged 2-23 months, were analyzed. ARI and CNS infections caused 58% (mortality rate: 31 per 1,000 live-births; 95% CI: 23, 41) and 17% (mortality rate: 9 per 1,000 live-births; 95% CI: 5, 16), respectively, of all deaths within this age group. Between the ages of 2 and 23 months, 5% of all babies born alive died of ARI, and another 1% died of CNS infections. Our results indicate that current efforts to reduce childhood mortality should focus on reducing ARI and meningitis. These efforts should include evaluating the impact of Hib and pneumococcal vaccines within the routine Expanded Programme on Immunization system.

Intracellular parasitism by the human granulocytic ehrlichiosis bacterium through the P-selectin ligand, PSGL-1

Human granulocytic ehrlichiosis (HGE) is a febrile tick-borne illness caused by a recently discovered intracellular bacterium remarkable for its tropism for professionally phagocytic neutrophils. Monoclonal antibodies against the P-selectin binding domain of the leukocyte P-selectin glycoprotein ligand, PSGL-1, prevented HGE cell binding and infection, as did enzymatic digestion of PSGL-1. Furthermore, simultaneous neoexpression in nonsusceptible cells of complementary DNAs for both PSGL-1 and its modifying alpha-(1,3) fucosyltransferase, Fuc-TVII, allowed binding and infection by HGE. Thus, the HGE bacterium specifically bound to fucosylated leukocyte PSGL-1. Selectin mimicry is likely central to the organism's unique ability to target and infect neutrophils.

Omega-3 polyunsaturated fatty acid regulation of gene expression

This review describes the mechanisms by which polyunsaturated fatty acids regulate the activity of the nuclear transcription factors, peroxisome proliferator-activated receptor and sterol regulatory element binding protein-1, and it describes the role that the peroxisome proliferator-activated receptor and sterol regulatory element binding protein-1 play in coordinating the regulation of lipid synthesis, lipid oxidation, and thermogenesis. Finally, the requirement for dietary polyunsaturated fatty acids, particularly n-3 fatty acids, is defined in terms of the effects polyunsaturated fatty acids exert on gene expression and the role that these effects play in overall energy balance.

Quantitative relationship among integrin-ligand binding, adhesion, and signaling via focal adhesion kinase and extracellular signal-regulated kinase 2

Because integrin-mediated signals are transferred through a physical architecture and synergistic biochemical network whose properties are not well defined, quantitative relationships between extracellular integrin-ligand binding events and key intracellular responses are poorly understood. We begin to address this by quantifying integrin-mediated FAK and ERK2 responses in CHO cells for varied alpha(5)beta(1) expression level and substratum fibronectin density. Plating cells on fibronectin-coated surfaces initiated a transient, biphasic ERK2 response, the magnitude and kinetics of which depended on integrin-ligand binding properties. Whereas ERK2 activity initially increased with a rate proportional to integrin-ligand bond number for low fibronectin density, the desensitization rate was independent of integrin and fibronectin amount but proportional to the ERK2 activity level with an exponential decay constant of 0.3 (+/- 0.08) min(-1). Unlike the ERK2 activation time course, FAK phosphorylation followed a superficially disparate time course. However, analysis of the early kinetics of the two signals revealed them to be correlated. The initial rates of FAK and ERK2 signal generation exhibited similar dependence on fibronectin surface density, with both rates monotonically increasing with fibronectin amount until saturating at high fibronectin density. Because of this similar initial rate dependence on integrin-ligand bond formation, the disparity in their time courses is attributed to differences in feedback regulation of these signals. Whereas FAK phosphorylation increased to a steady-state level as new integrin-ligand bond formation continued during cell spreading, ERK2 activity was decoupled from the integrin-ligand stimulus and decayed back to a basal level. Accordingly, we propose different functional metrics for representing these two disparate dynamic signals: the steady-state tyrosine phosphorylation level for FAK and the integral of the pulse response for ERK2. These measures of FAK and ERK2 activity were found to correlate with short term cell-substratum adhesivity, indicating that signaling via FAK and ERK2 is proportional to the number of integrin-fibronectin bonds.

Invasion and intracellular development of the human granulocytic ehrlichiosis agent in tick cell culture

Human granulocytotropic ehrlichias are tick-borne bacterial pathogens that cause an acute, life-threatening illness, human granulocytic ehrlichiosis (HGE). Ehrlichias within neutrophil granulocytes that invade tick bite sites are likely ingested by the vector, to be transmitted to another mammalian host during the tick's next blood meal. Thus, the cycle of replication and development in the vector is prerequisite to mammalian infection, and yet these events have not been described. We report tick cell culture isolation of two strains of the HGE agent directly from an infected horse and a dog and have also established a human isolate from HL60 culture in tick cells, proving that the blood stages of the HGE agent are infectious for tick cells, as are those replicating in the human cell line HL60. This required changes to the culture system, including a new tick cell line. In tick cell layers, the HGE agent induced foci of infection that caused necrotic plaques and eventual destruction of the culture. Using the human isolate and electron microscopy, we monitored adhesion, internalization, and replication in vector tick cells. Both electron-lucent and -dense forms adhered to and entered cells by a mechanism reminiscent of phagocytosis. Ehrlichial cell division was initiated soon after, resulting in endosomes filled with numerous ehrlichias. During early development, pale ehrlichias with a tight cell wall dominated, but by day 2, individual bacteria condensed into dark forms with a rippled membrane. These may become compacted into clumps where individual organisms are barely discernible. Whether these are part of an ehrlichia life cycle or are degenerating is unknown.

A cloned CD15s-negative variant of HL60 cells is deficient in expression of FUT7 and does not adhere to cytokine-stimulated endothelial cells

The initial steps of leukocyte adhesion depend on selectin/ligand interactions. Surface ligands on leukocytes are often modified by addition of the sialyl Lewis x (CD15s) determinant. Biosynthesis of CD15s is dependent upon alpha(2,3)sialyltransferases and alpha(1,3)fucosyltransferases. We report the isolation of an HL60 cell line variant, HL60A2, that no longer expresses CD15s. HL60A2 cells do not adhere to cytokine-stimulated endothelial cells. Enzymatic assays reveal that this cell line has normal alpha(2,3)sialyltransferase activity but is deficient in the alpha(1,3)fucosyltransferase responsible for biosynthesis of CD15s (FUT7). The fucosyltransferase that constructs the non-sialylated antigen, Lewis x (CD15), is expressed at high levels (FUT4). Transcript analyses show that FUT7 and FUT4 are inversely expressed in HL60 and variant cell lines. HL60A2 cells provide a tool to study the regulation of selectin ligands and corresponding human fucosyltransferase genes.

Plasma lipoprotein fatty acids are altered by the positional distribution of fatty acids in infant formula triacylglycerols and human milk

BACKGROUND

Triacylglycerol digestion involves hydrolysis of fatty acids esterified at the glycerol 1,3 positions by gastric and pancreatic lipase to produce 2-monoacylglycerols and unesterified fatty acids, which are then absorbed, reesterified to triacylglycerol, and secreted in chylomicrons. Palmitic acid (16:0) is predominantly esterified to the 2 position of human milk triacylglycerol but to the 1,3 positions in the oils used in infant formulas.

OBJECTIVE

We aimed to determine whether the position of 16:0 in human milk and infant formula triacylglycerol influences the position of fatty acids in postprandial plasma chylomicron triacylglycerol.

DESIGN

Full-term infants were fed formula with 25-27% 16:0 with either 39% of the 16:0(synthesized triacylglycerol) or 6% of the 16:0 (standard formula) esterified at the triacylglycerol 2 position, or were breast-fed (23% 16:0, 81% at the triacylglycerol 2 position) from birth to 120 d of age. Chylomicron fatty acids and plasma lipids were assessed at 30 and 120 d of age.

RESULTS

Infants fed the synthesized triacylglycerol formula, standard formula, or breast milk had 15.8%,8.3%, and 28.0% 16:0 in the chylomicron triacylglycerol 2 position (P < 0.05). These results suggest that >/=50% of the dietary triacylglycerol 2-position 16:0 is conserved through digestion, absorption, and chylomicron triacylglycerol synthesis in breast-fed and formula-fed infants. Infants fed the synthesized triacylglycerol formula had significantly lower HDL-cholesterol and apolipoprotein A-I and higher apolipoprotein B concentrations than infants fed the standard formula.

CONCLUSION

Dietary triacylglycerol fatty acid distribution may alter lipoprotein metabolism in young infants.

Leukocyte infection by the granulocytic ehrlichiosis agent is linked to expression of a selectin ligand

Human granulocytic ehrlichiosis (HGE) is an emerging tickborne illness caused by an intracellular bacterium that infects neutrophils. Cells susceptible to HGE express sialylated Lewis x (CD15s), a ligand for cell selectins. We demonstrate that adhesion of HGE to both HL60 cells and normal bone marrow cells directly correlates with their CD15s expression. HGE infection of HL60 cells, bone marrow progenitors, granulocytes, and monocytes was blocked by monoclonal antibodies against CD15s. However, these antibodies did not inhibit HGE binding, and anti-CD15s was capable of inhibiting the growth of HGE after its entry into the target cell. In contrast, neuraminidase treatment of HL60 cells prevented both HGE binding and infection. A cloned cell line (HL60-A2), derived from HL60 cells and resistant to HGE, was deficient in the expression of alpha-(1, 3)fucosyltransferase (Fuc-TVII), an enzyme known to be required for CD15s biosynthesis. Less than 1% of HL60-A2 cells expressed CD15s, and only these rare CD15s-expressing cells bound HGE and became infected. After transfection with Fuc-TVII, cells regained CD15s expression, as well as their ability to bind HGE and become infected. Thus, CD15s expression is highly correlated with susceptibility to HGE, and it, and/or a closely related sialylated and alpha-(1,3) fucosylated molecule, plays a key role in HGE infection, an observation that may help explain the organism's tropism for leukocytes.

Use of SoloShot autodestruct syringes compared with disposable syringes, in a national immunization campaign in Indonesia

Autodestruct syringes can reduce the improper reuse of syringes, which present a significant risk in the transmission of bloodborne pathogens in developing countries, especially during immunization campaigns owing to the high number of injections given per session. SoloShot is an autodestruct syringe, distributed by UNICEF, which has been shown to be safer and easier to use than standard syringes. This study analyses the accuracy and dose-efficiency of SoloShot, compared with disposable syringes, during a national tetanus toxoid immunization campaign on the Indonesian island of Lombok. Observation and dose measurements revealed that SoloShot syringes delivered more precise and consistent doses and 15% more doses per vial than disposable syringes. Vaccine savings may partially be offset by the higher price of SoloShot. Vaccinators preferred SoloShot, describing it as easier to use, faster, and more accurate than the disposable syringe. The study indicates that SoloShot is highly appropriate for use in immunization campaigns by reducing vaccine wastage and improving injection safety.

Home delivery of heat-stable vaccines in Indonesia: outreach immunization with a prefilled, single-use injection device

Extending immunization coverage to underserved populations will require innovative immunization strategies. This study evaluated one such strategy: the use of a prefilled, single-use injection device for outreach immunization by village midwives. The device, UniJect, is designed to prevent refilling or reuse. Stored at ambient temperatures for up to 1 month in midwives' homes, vaccine-filled UniJect devices were immediately available for outreach. Between July 1995 and April 1996, 110 midwives on the Indonesia islands of Lombok and Bali visited the homes of newborn infants to deliver hepatitis B vaccine to the infants and tetanus toxoid to their mothers. Observations and interviews showed that the midwives used the device properly and safely to administer approximately 10,000 sterile injections in home settings. There were no problems with excessive heat exposure during the storage or delivery of vaccine. Injection recipients and midwives expressed a strong preference for the UniJect device over a standard syringe. Use of the prefilled device outside the cold chain simplified the logistics and facilitated the speed and efficiency of home visits, while the single-dose format minimized vaccine wastage.

Effects of pollen quality and genotype on the dance of foraging honey bees

Animals assess the quality and quantity of food and choose among different foods based on these assessments. We explored whether there was genetic variation for assessment of pollen quality by foraging honey bees, Apis mellifera. Honey bees derived from two genotypic strains foraged for pollen of varying quality from a petri dish placed inside an outdoor flight cage. The strains were the result of a colony-level, two-way selection on amount of stored pollen. We used the forager's round dance to quantify the assessments of pollen quality by individually marked worker bees. The dance rate (number of 180 degrees turns per minute) and the probability of dancing were each greater when bees foraged for pure pollen compared with a lower-quality mixture of pollen and alpha-cellulose (1:1 by volume). Bees from the high-pollen genotypic strain had a higher dance rate than those from the low-pollen strain, suggesting different assessments. Bees from the low-pollen strain, however, had a higher probability of dancing than did bees from the high-pollen strain. Dance duration was not affected by a bee's strain or by the quality of pollen. We conclude that the dance rate may be used to quantify a forager's subjective evaluation of pollen quality and that this evaluation has a genetic component. Our results also suggest that the dance may function at the colony level to recruit bees to more profitable pollen sources. Copyright 1998 The Association for the Study of Animal Behaviour.

Immunodiagnosis of human granulocytic ehrlichiosis by using culture-derived human isolates

Human granulocytic ehrlichiosis (HGE) is an emerging infection caused by an Ehrlichia species closely related to Ehrlichia equi and Ehrlichia phagocytophila. Recent advances in the isolation and cultivation of this organism have allowed us to develop an immunofluorescence assay (IFA), enzyme immunoassay (EIA), and Western immunoblotting (WB) using HL-60 cell culture-derived human isolates. Antibody was detected in sera from culture-confirmed HGE patients by IFA and EIA, and these samples were reactive when analyzed by immunoblot analysis. HGE patient sera had high antibody titers and did not react with uninfected HL-60 cells. When IFA, EIA, and WB were used to analyze sera from healthy donors or those with a range of other disorders, including infections caused by Ehrlichia chaffeensis, Rickettsia rickettsii, and Coxiella burnetti, no significant cross-reactivity could be detected by EIA or immunoblot analysis with the exception of two of four serum samples from R. rickettsii-infected patients that were reactive by IFA only. Sera from HGE patients did not significantly cross-react in serologic tests for Borrelia burgdorferi. Using sera from patients previously enrolled in two clinical trials of treatment for early Lyme disease, we evaluated a two-step approach for estimation of the seroprevalence of antibodies reactive with the etiologic agent of HGE. On the basis of the immunoblot assay results for sera from culture-confirmed HGE patients, WB was used to confirm the specificity of the antibody detected by EIA and IFA. EIA was found to be superior to IFA in the ability to detect WB-confirmed antibodies to the HGE agent. When EIA and WB were used, 56 (19.9%) patients with early Lyme disease (n = 281) had either specific immunoglobulin M (IgM) or IgG antibodies; 38 patients (13.5%) had IgM only, 6 (2.1%) had IgG only, and 12 (4.3%) had both IgM and IgG. Therefore, Lyme disease patients are at high potential risk for exposure to Ehrlichia. Analysis by immunoblotting of serial samples from persons with culture-confirmed HGE or patients with Lyme disease and antibodies to the agent of HGE revealed a reproducible pattern of the immune response to specific antigens. These samples confirmed the importance of the 42- to 45-kDa antigens as early, persistent, and specific markers of HGE infection. Other significant immunogenic proteins appear at 20, 21, 28, 30, and 60 kDa. Use of the two-test method of screening by EIA and confirming the specificity by WB appears to offer a sound approach to the clinical immunodiagnosis of HGE.

Comparison of a mathematical model to predict 10-km performance from the Conconi test and ventilatory threshold measurements

The purpose of this study was to validate a mathematical model (MM) that evaluates the Conconi test and predicts 10-km race time. In addition, the relationship between ventilatory threshold (Tvent) determined from a laboratory test and heart rate deflection (HRd) from the Conconi test were examined. Seventeen trained runners performed the Conconi test, and performance times were predicted using a MM based on a logistics function. A correlational analysis indicated a highly significant relationship (r = .98, p < .01) between MM predicted time and actual time. Significant relationships were found between velocity at Tvent and HRd (r = .95, p < .01), and predicted times from each method (r = .96, p < .01). Heart rates from Tvent and HRd were also related (r = .79, p < .01). These results suggest that a MM of the Conconi test is a valid method of predicting 10-km performance and is closely related to traditional laboratory measures.

Primary bone marrow progenitors of both granulocytic and monocytic lineages are susceptible to infection with the agent of human granulocytic ehrlichiosis

Human granulocytic ehrlichiosis (HGE) is an emerging tickborne infection resulting in an acute febrile illness associated with cytopenias and characteristic intracellular organisms within peripheral blood granulocytes. The etiologic agent of HGE has recently been isolated and cultivated in the HL-60 promyelocytic leukemia cell line, but the spectrum of host cells that it naturally infects remains unknown. To determine if normal hematopoietic progenitors could be targets of infection, CD34+ primary human bone marrow cells, stimulated to differentiate along myelomonocytic lineages, were incubated with the HGE agent. Immature marrow progenitors and, remarkably, not only granulocytic but also CD14+ monocytic cells from these cultures supported replication of the HGE agent, suggesting that all are potential targets of infection in vivo. Infection of bone marrow progenitors may contribute to the hematologic manifestations of HGE. Furthermore, the ability of the agent to interact with monocytes has significant implications regarding disease pathogenesis and host response.

Incidence of iron-deficiency anaemia and depleted iron stores among nine-month-old infants in Vancouver, Canada

The iron status and feeding practices of 434 infants in Vancouver were determined at 39 +/- 1 week of age. Iron-deficiency anaemia (haemoglobin < or = 101 g/L, or < or = 110 g/L with two or three abnormal results from tests of serum ferritin, zinc erythrocyte protoporphyrin and total iron binding capacity) occurred in 7% of infants. Low iron stores (serum ferritin < 10 micrograms/l) occurred in about 24% of infants. Iron-deficiency anaemia was significantly associated (p < 0.001) with duration of breastfeeding. The prevalence of iron-deficiency anaemia among infants breastfed for 8 months was 15%. At 39 weeks (9 months) of age, about 5% and 13% of the infants were bottle-fed with cows milk or low iron infant formula, respectively, and this was also significantly associated (p < 0.02) with low iron stores. Iron-fortified infant cereals had been introduced to 95% of the infants by six months of age. This study shows iron-deficiency anaemia is a problem among a significant number of nine-month-old infants in Canada, and is not explained by failure to introduce iron-fortified infant cereals.

School-based wraparound planning: integrating services for students with emotional and behavioral needs

The wraparound process for planning unique and flexible services emerged from community-based human-service programs for children and youth exhibiting serious emotional disturbance. The application of wraparound in schools is described and illustrated via examples of local, statewide, and national initiatives. These experiences suggest strategies that can improve the school's effectiveness in serving students with, or at risk of, emotional and behavioral challenges.

Antibiotic susceptibility of the newly cultivated agent of human granulocytic ehrlichiosis: promising activity of quinolones and rifamycins

Human granulocytic ehrlichiosis (HGE) is a rapidly emerging tick-borne infection which presents as an acute febrile illness and is associated with hematologic abnormalities, elevated hepatic transaminase levels, and characteristic intracellular organisms in peripheral blood granulocytes. Although HGE has been successfully treated with tetracyclines, its susceptibility to other antibiotics remains unknown. No clear treatment alternative exist for young children, pregnant women, or allergic individuals, in whom tetracyclines are contra-indicated. We performed in vitro antibiotic susceptibility tests with this recently isolated agent grown in the human promyelocytic leukemia cell line HL-60. Doxycycline (MIC, 0.25 micrograms/ml), rifampin (MIC, 0.5 micrograms/ml), rifabutin (MIC, < or = 0.125 micrograms/ml), ciprofloxacin and ofloxacin (both with MICs of 2 micrograms/ml), and trovafloxacin (MIC, < or = 0.125 micrograms/ml) ciprofloxacin and ofloxacin (both with MICs of 2 micrograms/ml), and trovafloxacin (MIC, < or = 0.125 micrograms/ml) demonstrated significant activity against the HGE agent. These agents were also bactericidal. The HGE agent was resistant to clindamycin, trimethoprim-sulfamethoxazole, and imipenem-cilastatin, as well as to ampicillin, ceftriaxone, erythromycin, and azithromycin, antibiotics commonly used to treat Lyme disease. Both chloramphenicol and gentamicin had weak inhibitory activities but were not bactericidal. Our findings confirm the observed clinical efficacy of doxycycline and further suggest that the rifamycins and quinolones, particularly trovafloxacin, hold promise as alternative agents for treating this new infection.

Feeding formula without arachidonic acid and docosahexaenoic acid has no effect on preferential looking acuity or recognition memory in healthy full-term infants at 9 mo of age

Preferential looking acuity and novelty preference (a test of recognition memory) were determined by using Teller Acuity Cards and the Fagan Test of Infant Intelligence, respectively, for 399-433 healthy full-term infants at 39 +/- 1 wk of age. Duration of breast-feeding and age of infant at introduction and amount and type of formula were determined by questionnaire. Seventy-four infants (17%) were never breast-fed; another 92 infants (21%) were still receiving breast milk as the milk source at 39 wk of age. There were no differences in visual acuity or novelty preference among the infants when they were stratified by incidence or duration of breast-feeding. The formulas met current Canadian guidelines with > or = 0.7% of energy as linolenic acid, but had no docosahexaenoic or arachidonic acid. The studies indicate that formulas containing adequate linoleic and linolenic acids, without arachidonic or docosahexaenoic acid, impose no measurable deficits in performance in these visual and cognitive developmental tests at 9 mo of age in healthy full-term infants.

Dobutamine stress echocardiography: a new, noninvasive method for detecting ischemic heart disease

Pharmacologic induction of exercise with dobutamine hydrochloride, coupled with the technology of echocardiography, is an alternate method for evaluating ischemic heart disease. Dobutamine stress echocardiography involves obtaining echocardiographic images before, during, and after a titrated dobutamine infusion is administered. The study is positive if global or regional ventricular wall motion abnormalities develop. With our changing health care environment, this cost-effective, noninvasive diagnostic procedure is becoming a standard for determining the presence of coronary artery disease in those individuals who are unable or unwilling to undergo exercise stress testing.

Isolation of the equine granulocytic ehrlichiosis agent, Ehrlichia equi, in tick cell culture

The equine granulocytic ehrlichiosis agent, Ehrlichia equi, is closely related or identical to the human granulocytic ehrlichiosis (HGE) agent. Both are suspected of being transmitted by ticks. We have successfully isolated E. equi in a cell line, IDE8, derived from a putative vector, the tick Ixodes scapularis. Peripheral blood leukocytes from an experimentally infected horse were inoculated onto IDE8 monolayers. Cultures were incubated in a candle jar at 34 degrees C in tick cell culture medium with NaHCO3 and an organic buffer [3-(N-morpholino)-propanesulfonic acid] (MOPS). Within 2 weeks, infected cells were detected in Giemsa-stained culture samples, and the organisms subsequently spread to uninfected cells in the cultures. E. equi was passaged serially by transferring a portion of an infected culture to new cell layers every 2 to 3 weeks. The identity of the organisms was confirmed by PCR using oligonucleotide primers specific for E. equi and the HGE agent and by immunocytology. Homologous equine antibodies and human anti-HGE convalescent serum recognized E. equi grown in tick cell culture. Electron microscopy revealed electron-lucent and -dense ehrlichia-like forms developing within host cell endosomes. E. equi passaged twice in tick cell culture retained infectivity and pathogenicity for the equine host, as demonstrated by intravenous inoculation of a suspension of infected tick cells and subsequent reisolation from peripheral blood, in fulfillment of Koch's postulates. The horse developed severe clinical signs, i.e., fever, inappetence, thrombocytopenia, icterus, and limb edema, typical of granulocytic equine ehrlichiosis, within 1 week.

LU103793 (NSC D-669356): a synthetic peptide that interacts with microtubules and inhibits mitosis

LU103793 (NSC D-669356) is a new synthetic derivative of Dolastatin 15, an antiproliferative compound which was isolated from the mollusk Dolabella auricularia. Like Dolastatin 15, LU103793 is highly cytotoxic in vitro (IC50 = 0.1 nM). To investigate the mechanism of action of LU103793, we used a combination of biochemical and cellular methods. Turbidity assays with bovine brain microtubules demonstrated that LU103793 inhibits microtubule polymerization in a concentration-dependent manner (IC50 = 7 microM). Treatment with this compound also induced depolymerization of preassembled microtubules. Cell cycle analysis of tumor cell lines treated with LU103793 indicated a block in the G2-M phase. At the cellular level, it induced depolymerization of microtubules in interphase cells and development of abnormal spindles and chromosome distribution in mitotic cells. Although these effects are very similar to the cellular alterations caused by vinblastine, LU103793 does not inhibit vinblastine binding to unpolymerized tubulin in vitro. Our results suggest that LU103793 exerts its cytotoxic activity primarily through disruption of microtubule organization.

Impact of physician awareness on hospital charges for radical retropubic prostatectomy

PURPOSE

We determine if physician awareness of hospital costs for radical retropubic prostatectomy affects physician practice patterns.

MATERIALS AND METHODS

We reviewed 256 consecutive radical retropubic prostatectomies performed by 14 urologists during 4 years at a community hospital. After 2 years the physicians were provided information on factors that may decrease charges.

RESULTS

Charges decreased significantly following intervention, from +f417,134 within the initial 2 years to +f413,826 within the last 2 years (p < 0.005). Significant decreases were noted for length of stay, need for intensive care, operating time and blood loss.

CONCLUSIONS

Traditional methods of physician education can impact practice patterns to decrease hospital charges for radical retropubic prostatectomy.

The role of the physician in effecting change in hospital charge for radical prostatectomy

BACKGROUND

Continuing effort is being made to provide the best medical care in a cost-effective manner, requiring an evaluation of factors that control charges. The number of cases of carcinoma of the prostate gland and the number of radical retropubic prostatectomies performed have increased in recent years, with an estimate of several hundred million dollars being spent annually on this procedure in the United States of America. Because physicians are reported to effect the majority of charges for a hospitalization, this study examines the influence of notification of the physician of hospital charges on the overall hospital charges for radical retropubic prostatectomy.

STUDY DESIGN

Total hospital charge and duration per hospitalization were determined for all patients having radical prostatectomies performed at five community hospitals in Richmond, VA, between January 1991 and December 1993. Patients included 625 males diagnosed with carcinoma of the prostate gland undergoing radical prostatectomy by one of 20 urologists from several different private practice groups. Halfway into the time period studied, physicians were notified of data collection and of factors that seemed to have a role in hospital charges. Total hospital charges before and after physician notification were measured to determine whether or not physicians could effect hospital charges.

RESULTS

Overall, hospital charges decreased significantly after notification of physicians in the study. The decline in total charges continued throughout the follow-up period. Duration of hospitalization decreased throughout the entire study period, while total charge per hospital day increased.

CONCLUSIONS

Physician awareness of hospital charges for operative procedures and accompanying hospitalizations may influence the overall decrease in charges.

The UL45 gene product is required for herpes simplex virus type 1 glycoprotein B-induced fusion

Herpes simplex virus type 1 (HSV-1) syncytial (syn) mutants cause formation of giant polykaryocytes and have been utilized to identify genes promoting or suppressing cell fusion. We previously described an HSV-1 recombinant, F1 (J.L. Goodman, M. L. Cook, F. Sederati, K. Izumi, and J. G. Stevens, J. Virol. 63:1153-1161, 1989), which has unique virulence properties and a syn mutation in the carboxy terminus of glycoprotein B (gB). We attempted to replace this single-base-pair syn mutation through cotransfection with a 379-bp PCR-generated fragment of wild-type gB. The nonsyncytial viruses isolated were shown by DNA sequencing not to have acquired the expected wild-type gB sequence. Instead, they had lost their cell-cell fusion properties because of alterations mapping to the UL45 gene. The mutant UL45 gene is one nonsyncytial derivative of F1, A4B, was found to have a deletion of a C at UL45 nucleotide 230, resulting in a predicted frame shift and termination at 92 rather than 172 amino acids. Northern (RNA) analysis showed that the mutant UL45 gene was normally transcribed. However, Western immunoblotting showed no detectable UL45 gene product from A4B or from another similarly isolated nonsyncytial F1 derivative, A61B, while another such virus, 1ACSS, expressed reduced amounts of UL45. When A4B was cotransfected with the wild-type UL45 gene, restoration of UL45 expression correlated with restoration of syncytium formation. Conversely, cloned DNA fragments containing the mutant A4B UL45 gene transferred the loss of cell-cell fusion to other gB syn mutants, rendering them UL45 negative and nonsyncytial. We conclude that normal UL45 expression is required to allow cell fusion induced by gB syn mutants and that the nonessential UL45 protein may play an important role as a mediator of fusion events during HSV-1 infection.

Development of visual acuity in relation to plasma and erythrocyte omega-6 and omega-3 fatty acids in healthy term gestation infants

The development of preferential looking acuity was studied prospectively to 3 mo of age in exclusively breast-fed and formula-fed term gestation infants. The formula contained (% of total fatty acids) 17.9% linoleic acid (18:2 omega-6) and 2.1% alpha-linolenic acid (18:3 omega-3) but no docosahexaenoic acid (22:6 omega-3) or arachidonic acid (20:4 omega-6). The breast milk contained (mean +/- SEM) 13.4 +/- 0.8% 18:2 omega-6, 1.5 +/- 0.1% 18:3 omega-3, 0.51 +/- 0.03% 20:4 omega-6, and 0.22 +/- 0.02% 22:6 omega-3. Preferential looking acuity, assessed by the acuity-card procedure, and plasma phospholipid and erythrocyte phosphatidylcholine and phosphatidylethanolamine fatty acids were determined at 14 d and 3 mo of age. There were no significant differences in acuity at 14 d or 3 mo, despite substantial differences in erythrocyte and plasma lipid 22:6 omega-3. Visual acuity was [mean (cycles/degree) +/- SD (octaves)] 3.93 +/- 0.54 and 4.77 +/- 0.48 and erythrocyte phosphatidylethanolamine %22:6 omega-3 was (mean +/- SE) 7.6 +/- 0.5 and 4.0 +/- 0.2 in the 3-mo-old breast-fed and formula-fed infants, respectively. These studies show that feeding formula containing 2.1% 18:3 omega-3 (approximately 1.0% energy) results in development of visual acuity similar to breast-feeding in term infants to > or = 3 mo of age.

Evidence that palmitic acid is absorbed as sn-2 monoacylglycerol from human milk by breast-fed infants

Milk fatty acids consist of about 20-25% palmitic acid (16:0), with about 70% of 16:0 esterified to the sn-2 position of the milk triacylglycerols. Hydrolysis of dietary triacylglycerols by endogeneous lipases produces sn-2 monoacylglycerols and free fatty acids, which are absorbed, reesterified, and then secreted into plasma. Unesterified 16:0 is not well absorbed and readily forms soaps with calcium in the intestine. The positioning of 16:0 at the sn-2 position of milk triacylglycerols could explain the high coefficient of absorption of milk fat. However, the milk lipase, bile salt-stimulated lipase, has been suggested to complete the hydrolysis of milk fat to free fatty acids and glycerol. These studies determined whether 16:0 is absorbed from human milk as sn-2 monopalmitin by comparison of the plasma triacylglycerol total and sn-2 position fatty acid composition between breast-fed and formula-fed term gestation infants. The human milk and formula had 21.0 and 22.3% of 16:0, respectively, with 54.2 and 4.8% 16:0 in the fatty acids esterified to the 2 position. The plasma triacylglycerol total fatty acids had 26.0 +/- 0.6 and 26.2 +/- 0.6% of 16:0, and the sn-2 position fatty acids had 23.3 +/- 3.3 and 7.4 +/- 0.7% of 16:0 in the three-month-old exclusively breast-fed (n = 17) and formula-fed (n = 18) infants, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Biochemical and functional approaches to study of fatty acid requirements for very premature infants

Plasma and RBC omega-6 and omega-3 fatty acids reflect the composition of these fatty acids in the diet, and their analyses seem unlikely to add little more to studies on infant fatty acid requirements than evidence that the milk or formula diet was adhered to. Tests of visual function, cognitive, and motor skill development, however, are sufficiently sensitive to demonstrate significant differences between groups of infants fed diets that differ only in fatty acid composition. These functional tests offer the potential for future research with modified formulas or expressed milk to determine not only fatty acid requirements but also to further fundamental understanding of the role of specific omega-6 and omega-3 fatty acids in CNS development and function.

Direct Observation of ClO from Chlorine Nitrate Photolysis

Chlorine nitrate photolysis has been investigated with the use of a molecular beam technique. Excitation at both 248 and 193 nanometers led to photodissociation by two pathways, CIONO(2) --> CIO + NO()2 and CIONO(2) --> Cl + NO3, with comparable yields. This experiment provides a direct measurement of the CIO product channel and consequently raises the possibility of an analogous channel in CIO dimer photolysis. Photodissociation of the CIO dimer is a critical step in the catalytic cycle that is presumed to dominate polar stratospheric ozone destruction. A substantial yield of CIO would reduce the efficiency of this cycle.

High-pressure, high-temperature bioreactor for comparing effects of hyperbaric and hydrostatic pressure on bacterial growth

We describe a high-pressure reactor system suitable for simultaneous hyperbaric and hydrostatic pressurization of bacterial cultures at elevated temperatures. For the deep-sea thermophile ES4, the growth rate at 500 atm (1 atm = 101.29 kPa) and 95 degrees C under hydrostatic pressure was ca. three times the growth rate under hyperbaric pressure and ca. 40% higher than the growth rate at 35 atm.

A combination of human cytomegalovirus (HCMV)-specific murine monoclonal antibodies exhibits synergistic antiviral activity in vitro

A combination of HCMV-specific monoclonal antibodies (MAbs) reactive with glycoproteins in gcI complexes which exhibit synergistic antiviral activity in vitro is described. MAbs directed against different structural and biological properties of HCMV have been selected to increase the antiviral activity against all possible strains, and to reduce the likelihood that resistant strains will emerge with prolonged exposure. Furthermore, in vitro analysis demonstrates that certain of the MAbs in the combination augment the virus-neutralizing activity of other component antibodies, thereby decreasing the amount of total antibody protein required to inhibit HCMV infection. Certain MAbs have been selected to inactivate extracellular virus during the early phase of HCMV infection, whereas others have been selected to prevent its spread once cells have been infected. These data suggest that a MAb cocktail may be useful for prophylaxis and treatment of patients at risk of life-threatening HCMV infections.

The human antibody response to streptococcal C5a peptidase

An ELISA was developed to measure antibody, both IgG and IgA, against the streptococcal C5a peptidase (SCP), in human sera and saliva. Generally, sera and saliva from young, uninfected children lacked antibody to SCP. In contrast, most sera and saliva specimens from healthy adults had measurable levels of anti-SCP IgG and SCP-specific secretory IgA (anti-SCP sIgA). Paired acute and convalescent sera from patients with streptococcal pharyngitis possessed significantly higher levels of anti-SCP IgG than did sera from healthy individuals. Sera containing high concentrations of anti-SCP immunoglobulin were capable of neutralizing SCP activity. A survey of healthy adults and children also showed that the latter were significantly less likely to have anti-SCP sIgA in their saliva. Detection of this antibody in greater than 90% of the saliva specimens obtained from children who had recently experienced streptococcal pharyngitis demonstrated that children can produce a secretory response. This is thought to be the first report of a secretory IgA response in humans to a somatic antigen of Streptococcus pyogenes.

Management of benign ureteral structures: open surgical repair or endoscopic dilation?

We reviewed 20 cases of ureteral strictures, 15 of which were secondary to ureteral trauma. Of the patients 6 were managed initially by open repair and 14 underwent endoscopic manipulation. All 6 open repairs were successful, compared to 9 of the 14 patients who underwent endoscopic dilation of the ureteral stricture. Of the 5 failures 3 were due to the inability to cannulate the strictured ureter with a guide wire and 2 failed to respond to balloon dilation. Of these 5 patients 4 were treated successfully by an open operation. There were no serious intraoperative or postoperative complications. The average hospitalization was less for the endoscopic group (2.1 days) compared to the open surgical group (8.3 days). Followup ranged from 6 to 48 months.

Pressure and Temperature Effects on Growth and Methane Production of the Extreme Thermophile Methanococcus jannaschii

The marine archaebacterium Methanococcus jannaschii was studied at high temperatures and hyperbaric pressures of helium to investigate the effect of pressure on the behavior of a deep-sea thermophile. Methanogenesis and growth (as measured by protein production) at both 86 and 90°C were accelerated by pressure up to 750 atm (1 atm = 101.29kPa), but growth was not observed above 90°C at either 7.8 or 250 atm. However, growth and methanogenesis were uncoupled above 90°C, and the high-temperature limit for methanogenesis was increased by pressure. Substantial methane formation was evident at 98°C and 250 atm, whereas no methane formation was observed at 94°C and 7.8 atm. In contrast, when argon was substituted for helium as the pressurizing gas at 250 atm, no methane was produced at 86°C. Methanogenesis was also suppressed at 86°C and 250 atm when the culture was pressurized with a 4:1 mix of H 2 and CO 2 , although limited methanogenesis did occur when the culture was pressurized with H 2 .

Antibody inhibition of HeLa cell invasion by Yersinia enterocolitica

Antisera were prepared in rabbits against formalized and heat-killed bacteria of Yersinia enterocolitica serotype O:5,27 and against formalized bacteria of serotype O:8. Both strains used for immunization demonstrated adhesion to and invasion of HeLa cells. Coating of the bacteria with antibody did not greatly alter adhesion (i.e., extracellular attachment) to HeLa cells; however, antibody against formalized bacteria of both serotypes inhibited HeLa cell invasion by the homologous and heterologous strains. The Fab fragments from purified immunoglobulins also demonstrated cross-reacting inhibition of HeLa cell invasion. Antibody against heat-killed bacteria of serotype O:5,27 had no inhibitory activity. Adsorption of the antiserum against formalized bacteria of serotype O:5,27 with lipopolysaccharide from the homologous strain removed anti-lipopolysaccharide antibody but did not remove the inhibitory activity. The antiserum against formalized bacteria of serotype O:8 showed no antibody against lipopolysaccharide from serotype O:5,27 and no agglutinins against heat-killed bacteria of this strain. From these results, it is tentatively suggested that protein structures are important in mediating epithelial cell invasion by Y. enterocolitica.

Obsidian Dating and East African Archeology

New experimental procedures have made it possible to establish specific hydration rates for the numerous compositional types of obsidian to be found at archeological sites in Kenya. Two rates are applied to artifacts from the Prospect Farm site, revealing a history of occupation extending back 120,000 years.