Bloodstream infections in haematological cancer patients colonized by multidrug-resistant bacteria.

Infections by multidrug-resistant (MDR) bacteria are a worrisome phenomenon in hematological patients. Data on the incidence of MDR colonization and related bloodstream infections (BSIs) in haematological patients are scarce. A multicentric prospective observational study was planned in 18 haematological institutions during a 6-month period. All patients showing MDR rectal colonization as well as occurrence of BSI at admission were recorded. One-hundred forty-four patients with MDR colonization were observed (6.5% of 2226 admissions). Extended spectrum beta-lactamase (ESBL)-producing (ESBL-P) enterobacteria were observed in 64/144 patients, carbapenem-resistant (CR) Gram-negative bacteria in 85/144 and vancomycin-resistant enterococci (VREs) in 9/144. Overall, 37 MDR-colonized patients (25.7%) developed at least one BSI; 23 of them (62.2%, 16% of the whole series) developed BSI by the same pathogen (MDRrel BSI), with a rate of 15.6% (10/64) for ESBL-P enterobacteria, 14.1% (12/85) for CR Gram-negative bacteria and 11.1% (1/9) for VRE. In 20/23 cases, MDRrel BSI occurred during neutropenia. After a median follow-up of 80 days, 18 patients died (12.5%). The 3-month overall survival was significantly lower for patients colonized with CR Gram-negative bacteria (83.6%) and VRE (77.8%) in comparison with those colonized with ESBL-P enterobacteria (96.8%). CR-rel BSI and the presence of a urinary catheter were independent predictors of mortality. MDR rectal colonization occurs in 6.5% of haematological inpatients and predicts a 16% probability of MDRrel BSI, particularly during neutropenia, as well as a higher probability of unfavourable outcomes in CR-rel BSIs. Tailored empiric antibiotic treatment should be decided on the basis of colonization.

'Real-life' report on the management of chronic GvHD in the Gruppo Italiano Trapianto Midollo Osseo (GITMO).

Several guidelines have been published about management of chronic GvHD (cGvHD), but the clinical practice still remains demanding. The Gruppo Italiano Trapianto di Midollo Osseo (GITMO) has planned a prospective observational study on cGvHD, supported by a dedicated software, including the updated recommendations. In view of this study, two surveys have been conducted, focusing the management of cGvHD and ancillary therapy in cGvHD, to address the current 'real life' situation. The two surveys were sent to all 57 GITMO centers, performing allografting in Italy; the response rate was 57% and 66% of the interviewed centers, respectively. The first survey showed a great disparity especially regarding steroid-refractory cGvHD, although extracorporeal photo-apheresis resulted as the most indicated treatment in this setting. Another challenging issue was the strategy for tapering steroid: our survey showed a great variance, and this disagreement could be a real bias in evaluating outcomes in prospective studies. As for the second survey, the results suggest that the ancillary treatments are not standardized in many centers. All responding centers reported a strong need to standardize management of cGvHD and to participate in prospective trials. Before starting observational and/or interventional studies, a detailed knowledge of current practice should be encouraged.

Access to emergency care services: a transversal ecological study about Brazilian emergency health care network.

OBJECTIVES: Studies of health geography are important in the planning and allocation of emergency health services. The geographical distribution of health facilities is an important factor in timely and quality access to emergency services; therefore, the present study analyzed the emergency health care network in Brazil, focusing the analysis at the roles of small hospitals (SHs). STUDY DESIGN: Cross-sectional ecological study. METHODS: Data were collected from 9429 hospitals of which 3524 were SHs and 5905 were high-complexity centers (HCCs). For analytical purposes, we considered four specialties when examining the proxies of emergency care capability: adult, pediatrics, neonatal, and obstetric. We analyzed the spatial distribution of hospitals, identifying municipalities that rely exclusively on SHs and the distance of these cities from HCCs. RESULTS: More than 14 and 30 million people were at least 120 km away from HCCs with an adult intensive care unit (ICU) and pediatric ICU, respectively. For neonatal care distribution, 12% of the population was more than 120 km away from a health facility with a neonatal ICU. The maternities situation is different from other specialties, where 81% of the total Brazilian population was within 1 h or less from such health facilities. CONCLUSION: Our results highlighted a polarization in distribution of Brazilian health care facilities. There is a concentration of hospitals in urban areas more developed and access gaps in rural areas and the Amazon region. Our results demonstrate that the distribution of emergency services in Brazil is not facilitating access to the population due to geographical barriers associated with great distances.

Thiotepa-based high-dose therapy for autologous stem cell transplantation in lymphoma: a retrospective study from the EBMT.

Clinical information about thiotepa-based autologous stem cell transplantation (auto-SCT) outside the primary central nervous system lymphoma (PCNSL) field is sparse. In this registry-based retrospective study, we evaluated potential risks and benefits of thiotepa-based preparative regimens compared with BEAM (carmustine, etoposide, cytarabine, melphalan) in auto-SCT for diffuse large B-cell lymphoma (DLBCL, excluding PCNSL), follicular lymphoma (FL) or Hodgkin lymphoma (HL). A total of 14 544 patients (589 thiotepa and 13 955 BEAM) met the eligibility criteria, and 535 thiotepa- and 1031 BEAM-treated patients were matched in a 1:2 ratio for final comparison. No significant differences between thiotepa and BEAM groups for any survival end point were identified in the whole sample or disease entity subsets. For a more detailed analysis, 47 TEAM (thiotepa, etoposide, cytarabine, melphalan)-treated patients were compared with 75 matched BEAM patients with additional collection of toxicity data. Again, there were no significant differences between the two groups for any survival end point. In addition, the frequency of common infectious and non-infectious complications including secondary malignancies was comparable between TEAM and BEAM. These results indicate that thiotepa-based high-dose therapy might be a valuable alternative to BEAM in DLBCL, HL and FL. Further evaluation by prospective clinical trials is warranted.

Hydrophilic interaction liquid chromatography-electrospray ionization-tandem mass spectrometry of a complex mixture of native and oxidized phospholipids.

A mixture of native and oxidized phospholipids (PLs), generated by the soybean lipoxygenase type V-catalyzed partial oxidation of a lipid extract obtained from human platelets, was analyzed by Hydrophilic Interaction Liquid Chromatography-ElectroSpray Ionization-Tandem Mass Spectrometry (HILIC-ESI-MS/MS). The complexity of the resulting mixture was remarkable, considering that the starting lipid extract, containing (as demonstrated in a previous study) about 130 native PLs, was enriched with enzymatically generated hydroperoxylated derivatives and chemically generated hydroxylated forms of PLs bearing polyunsaturated side chains. Nonetheless, the described analytical approach proved to be very powerful; indeed, focusing on phosphatidylcolines (PCs), the most abundant PL class in human platelets, about fifty different native/oxidized species could be identified in a single HILIC-ESI-MS/MS run. Low-energy collision induced dissociation tandem MS (CID-MS/MS) experiments on chromatographically separated species showed single neutral losses of H2O2 and H2O to be typical fragmentation pathways of hydroperoxylated PCs, whereas a single H2O loss was observed for hydroxylated ones. Moreover, diagnostic losses of n-hexanal or n-pentanol were exploited to recognize PCs hydroperoxylated on the last but five carbon atom of a É·-6 polyunsaturated side chain. Despite the low resolution of the 3D ion trap mass analyzer used, the described HILIC-ESI-MS/MS approach appears very promising for the identification of oxidized lipids in oxidatively stressed complex biological systems.

A mathematical model for filtration and macromolecule transport across capillary walls.

Metabolic substrates, such as oxygen and glucose, are rapidly delivered to the cells of large organisms through filtration across microvessels walls. Modelling this important process is complicated by the strong coupling between flow and transport equations, which are linked through the osmotic pressure induced by the colloidal plasma proteins. The microvessel wall is a composite media with the internal glycocalyx layer exerting a strong sieving effect on macromolecules, with respect to the external layer composed by the endothelial cells. The physiological structure of the microvessel is represented as the superimposition of two membranes with different properties; the inner membrane represents the glycocalyx, while the outer membrane represents the surrounding endothelial cells. Application of the mass conservation principle and thermodynamic considerations lead to a model composed of two coupled second-order ordinary differential equations for the hydrostatic and osmotic pressures, one, expressing volumetric mass conservation and the other, which is non-linear in the unknown osmotic pressure, expressing macromolecules mass conservation. Despite the complexity of the system, the assumption that the properties of the layers are piece-wise constant allows us to obtain analytical solutions for the two pressures. This solution is in agreement with experimental observations, which contrary to common belief, show that flow reversal cannot occur in steady-state conditions unless the hydrostatic pressure in the lumen drops below physiologically plausible values. The observed variations of the volumetric flux and the solute mass flux in case of a significant reduction of the hydrostatic pressure at the lumen are in qualitative agreement with observed variations during detailed experiments reported in the literature. On the other hand, homogenising the microvessel wall into a single-layer membrane with equivalent properties leads to a very different distribution of pressure across the microvessel walls, not consistent with observations.

Antithrombin plasma levels decrease is associated with preeclampsia worsening.

Antithrombin plasma levels (AT) have been found decreased in women with preeclampsia (PE), but little is known about the trend of AT during the course of this disease. We prospectively investigated AT in consecutive women admitted to our hospital with a diagnosis of PE, to assess if AT fluctuations could be associated with the evolution of the disease. AT, platelet count and D-dimer levels were determined every other day. In the 73 patients studied, AT, platelet count and fibrinogen progressively reduced during the observational period, reaching a nadir on the day of delivery, whereas D-dimer progressively increased over time. Statistical analysis was restricted to the 39 women that had an AT measurement performed on each of days -1, 0 and +1, with respect to the day of delivery. These subjects showed a significant decrease in AT on the day of delivery compared to the day just before (77.8 +/- 15.1%vs. 85.4 +/- 14.2%, P = 0.027), followed by a recovery on the first day after delivery (87.6 +/- 21.3% from 77.8 +/- 15.1%, P = 0.005). Our study demonstrates that a significant drop in AT levels is associated with the clinical worsening of PE, regardless of its severity.

Pathophysiology of bleeding in surgery.

Bleeding is a major surgical complication. Although mortality rates of 0.1% are observed for surgical procedures, it may be 5% to 8% for elective vascular surgery, and increase to 20% in the presence of severe bleeding. In major surgery for liver diseases, as well as in cardiac surgery, excessive blood loss is associated with increased mortality, morbidity, and intensive care stay. Approximately 75% to 90% of intraoperative and early postoperative bleeding is due to technical factors. However, in some cases either acquired or congenital coagulopathies may favor, if not directly cause, surgical hemorrhage. Uncontrolled bleeding leads to a combination of hemodilution, hypothermia, consumption of clotting factors, and acidosis, which in turn worsen the clotting process, further exacerbating the problem in a vicious bloody circle. At present, the standard treatment for surgical bleeding is the rapid control of the source of bleeding by either surgical or radiological techniques. Blood-derived products as well as hemostatic agents, such as aprotinin, tranexamic acid, and DDAVP, are widely used to improve hemostatic balance in bleeding patients. Recombinant activated factor VII (rFVIIa) has been reported to be effective for the treatment of surgical or traumatic massive bleeding unresponsive to conventional therapy. Although most reports are anecdotal, and therefore exposed to a "positive" selection bias, the number of cases is impressive, strongly suggesting that in such patients rFVIIa may afford a hemostatic advantage beyond that of conventional replacement therapy.

A verotoxin 1 B subunit-lambda CRO chimeric protein specifically binds both DNA and globotriaosylceramide (Gb(3)) to effect nuclear targeting of exogenous DNA in Gb(3) positive cells.

Inefficient nuclear incorporation of foreign DNA remains a critical roadblock in the development of effective nonviral gene delivery systems. DNA delivered by traditional protocols remains within endosomal/lysosomal vesicles, or is rapidly degraded in the cytoplasm. Verotoxin I (VT), an AB(5) subunit toxin produced by enterohaemorrhagic Escherichia coli, binds to the cell surface glycolipid, globotriaosylceramide (Gb(3)) and is internalized into preendosomes. VT is then retrograde transported to the Golgi, endoplasmic reticulum (ER), and nucleus of highly VT-sensitive cells. We have utilized this nuclear targeting of VT to design a unique delivery system which transports exogenous DNA via vesicular traffic to the nucleus. The nontoxic VT binding subunit (VTB) was fused to the lambda Cro DNA-binding repressor, generating a 14-kDa VTB-Cro chimera. VTB-Cro binds specifically via the Cro domain to a 25-bp DNA fragment containing the consensus Cro operator. VTB-Cro demonstrates simultaneous specific binding to Gb(3). Treatment of Vero cells with fluorescent-labeled Cro operator DNA in the presence of VTB-Cro, results in DNA internalization to the Golgi, ER, and nucleus, whereas fluorescent DNA alone is incorporated poorly and randomly within the cytoplasm. VTB-Cro mediated nuclear DNA transport is prevented by brefeldin A, consistent with Golgi/ER intracellular routing. Pretreatment with filipin had no effect, indicating that caveoli are not involved. This novel VTB-Cro shuttle protein may find practical applications in the fields of intracellular targeting, gene delivery, and gene therapy.

Myc is an essential negative regulator of platelet-derived growth factor beta receptor expression.

Platelet-derived growth factor BB (PDGF BB) is a potent mitogen for fibroblasts as well as many other cell types. Interaction of PDGF BB with the PDGF beta receptor (PDGF-betaR) activates numerous signaling pathways and leads to a decrease in receptor expression on the cell surface. PDGF-betaR downregulation is effected at two levels, the immediate internalization of ligand-receptor complexes and the reduction in pdgf-betar mRNA expression. Our studies show that pdgf-betar mRNA suppression is regulated by the c-myc proto-oncogene. Both constitutive and inducible ectopic Myc protein can suppress pdgf-betar mRNA and protein. Suppression of pdgf-betar mRNA in response to Myc is specific, since expression of the related receptor pdgf-alphar is not affected. We further show that Myc suppresses pdgf-betar mRNA expression by a mechanism which is distinguishable from Myc autosuppression. Analysis of c-Myc-null fibroblasts demonstrates that Myc is required for the repression of pdgf-betar mRNA expression in quiescent fibroblasts following mitogen stimulation. In addition, it is evident that the Myc-mediated repression of pdgf-betar mRNA levels plays an important role in the regulation of basal pdgf-betar expression in proliferating cells. Thus, our studies suggest an essential role for Myc in a negative-feedback loop regulating the expression of the PDGF-betaR.

[The rural labor process and health in the Southern Brazilian mountains: a descriptive study]. / Processo de produção rural e saúde na serra gaúcha: um estudo descritivo.

This cross-sectional study among rural workers in the mountainous region of the southernmost Brazilian State of Rio Grande do Sul was designed to identify the characteristics of work performed on family farms. The research focused on the socio-demographic profiles of rural workers, identifying the characteristics of rural labor and describing the prevalence of some disease entities in such populations. Some 1479 rural workers from 495 farms were interviewed. In this sample, 87% of the individuals were members of the farm-owning family, mean age was 41 years, 56% were males, and mean schooling was 5 years. Farms had a mean area of 37 hectares, 50% had at least one type of farm machinery, and fruits constituted the main crop. About 75% of workers handled several types of pesticides, while 12% reported at least one lifetime episode of pesticide poisoning. Prevalence of minor psychiatric disorders was 36%, and annual frequency of occupational injuries was 10%. There was a wide variety of activities and occupational risks. The high prevalence of health problems identified in the study calls attention to the need for measures to promote and protect rural workers' health.

Child labor and health: problems and perspectives.

Child labor remains a widespread problem. Although it can have positive effects, in some situations it has negative effects on health and development of the children. Although mainly a problem in developing countries, it is also possible to find child workers, some working in hazardous activities, in developed countries. The authors describe the child labor profiles in developed and developing countries, the principal occupations of children, and their concomitant hazards. They summarize the epidemiologic evidence for a greater impact of some occupational exposures on the health of children as compared with adults, and the theoretical concerns about the impact of child labor on health, and suggest policies that can be used to combat harmful child labor.

[A cross-sectional study about mental health of farm-workers from Serra Gaucha (Brazil)]. / Estudo transversal sobre saúde mental de agricultores da Serra Gaúcha (Brasil).

OBJECTIVE: In view of the shortage of population-based rural studies, this research project evaluated the associations between the characteristics of rural work and the occurrence of minor psychiatric disorders (MPD). METHODS: A cross sectional study was carried out on the 1,282 farm workers of 446 farms. Information about the farms (land extension, agricultural activities, technology and pesticide use) was collected. Demographic and socioeconomic data, characteristics of the work process and mental health indicators were obtained from the workers. RESULTS: MPD were found in 37.5% of the farm workers. The risk was higher on farms with a land extension of from 26 to 50 hectares, and lower where there was an increased level of job technology and schooling. The prevalence of MPD was higher among bean producers and lower among apple producers. Despite the impossibility of defining the direction of the causal link, pesticide poisoning was strongly associated with MPD. CONCLUSION: The results call attention to the dimension of the problem and to the importance of adopting new policies for the protection of farm workers' mental health.

[Workers' perception of exposure to workload and risks of accidents in a southern Brazilian city]. / Percepção de exposição a cargas de trabalho e riscos de acidentes em Pelotas, RS (Brasil).

OBJECTIVE: The study of the association between workers' perceptions of occupational hazards and the risk of occupational accidents. DESIGN: Case control study. POPULATION: The cases were 264 workers who presented a "typical" occupational accident, registered at the National Institute of Social Security in the city of Pelotas, between January and July, 1996. Fatal accidents (two) were excluded, as were those leading to an absence of less than seven days from work. The cases were interviewed in their homes with a standard questionnaire. For each case, three controls were chosen: a fellow-work, a neighbor and a population control. Controls were matched to the cases by age (+/- 5 years) and sex; workers who had suffered an occupational accident in the preceding month were excluded from the control group. All cases and controls were formally employed and lived in the urban area. The data were analyzed using conditional logistic regression. RESULTS AND CONCLUSIONS: The risk of occupational accidents was found to double among workers who reported having faced emergency situations at work, working in high places, facing constant danger or noisy environments. Working in uncomfortable positions or intense physical activities were associated with a 50% increase in risk. The remaining occupational hazards under study were not significantly associated with the risk of accidents. All of the above results were adjusted for confounding factors.

The Brazilian cohort of pulp and paper workers: the logistic of a cancer mortality study.

The International Agency for Research on Cancer (IARC) proposed this international historical cohort study trying to solve the controversy about the increased risk of cancer in the workers of the Pulp and Paper Industry. One of the most important aspects presented by this study in Brazil was the strategies used to overcome the methodological challenges, such as: data access, data accuracy, data availability, multiple data sources, and the large follow-up period. Through multiple strategies it was possible to build a Brazilian cohort of 3,622 workers, to follow them with a 93 percent success rate and to identify in 99 percent of the cases the cause of death. This paper, has evaluated the data access, data accuracy and the effectiveness of the strategies used and the different sources of data.

The molecular role of Myc in growth and transformation: recent discoveries lead to new insights.

A major dilemma facing the Myc researcher is understanding how c-Myc regulation of gene transcription translates into the proliferative and oncogenic activities mediated by c-Myc protein. Indeed, much effort has focused on attempting to link c-Myc activation of gene transcription with both cell cycle progression and transformation mechanisms. Considerable progress has been made in recent years, with the identification of new Myc binding proteins as well as novel cellular targets of Myc-Max complexes. These discoveries have yielded more than a few surprises and challenged those working in the field to rethink traditional paradigms. It is now evident that c-Myc can also repress the transcription of specific genes, and Myc-mediated repression appears to be linked to Myc-dependent transformation. We summarize the evidence on Myc biological and molecular functions with regard to Myc-Max transcriptional regulation. In addition, we reevaluate current models of Myc transcriptional modulation in light of the discovery of new Myc binding partners and novel downstream target genes. Finally, we explore whether direct transactivation of cellular genes by Myc-Max heterodimers is sufficient for the growth-promoting and transforming activities of Myc or whether other molecular activities of Myc, such as Myc-mediated repression, may play a key role.

[Use of outpatient services in an urban area of Southern Brazil: place and frequency]. / Utilização de serviços ambulatoriais em Pelotas: onde a população consulta e com que freqüência.

OBJECTIVE: The objective was determine the use of health services by the adult population in Pelotas, RS, Brazil. METHODS: A cross-sectional study was made on the basis of a population sample. One thousand six hundred and fifty-seven persons we interviewed during the months of March and June, 1992. A percentage of 9.7 of the sample was lost. RESULTS: Two dependents variables. One the type of service as determined by type of payment. The other the number of medical visits made during the previous year. The type of service was seen to be associated with the following social variables: social class, level of schooling and place of residence. The frequency of medical visits was associated with sex, risk factors and reasons for the visit. CONCLUSION: It was concluded that choice of the type of service depends more heavily in social class than other variables associated with the severity of the disease in question.

Myc represses the growth arrest gene gadd45.

The c-Myc protein strongly stimulates cellular proliferation, inducing cells to exit G0/G1 and enter the cell cycle. At a molecular level, Myc prevents growth arrest and drives cell cycle progression through the transcriptional regulation of Myc-target genes. Expression of the growth arrest and DNA damage inducible gene 45 (gadd45) is elevated in response to DNA damaging agents, such as ionizing radiation via a p53-dependent mechanism, upon nutrient deprivation, or during differentiation. Gadd45 holds a vital role in growth arrest as ectopic expression confers a strong block to proliferation. Exposure of quiescent cells to mitogen stimulates a rapid increase in c-Myc expression which is followed by the subsequent reduction in gadd45 expression. The kinetics of these two regulatory events suggest that Myc suppresses the expression of gadd45, contributing to G0/G1 phase exit of the cell cycle. Indeed, ectopic Myc expression in primary and immortalized fibroblasts results in the suppression of gadd45 mRNA levels, by a mechanism which is independent of cell cycle progression. Using an inducible MycER system, rapid suppression of gadd45 mRNA is first evident approximately 0.5 h following Myc activation. The reduction in gadd45 mRNA expression occurs at the transcriptional level and is mediated by a p53-independent pathway. Moreover, Myc suppression and p53 induction of gadd45 following exposure to ionizing radiation are non-competitive co-regulatory events. Myc suppression of gadd45 defines a novel pathway through which Myc promotes cell cycle entry and prevents growth arrest of transformed cells.

The Myc negative autoregulation mechanism requires Myc-Max association and involves the c-myc P2 minimal promoter.

Increasing evidence supports an important biological role for Myc in the downregulation of specific gene transcription. Recent studies suggest that c-Myc may suppress promoter activity through proteins of the basal transcription machinery. We have previously reported that Myc protein, in combination with additional cellular factors, suppresses transcription initiation from the c-myc promoter. To characterize the cis components of this Myc negative autoregulation pathway, fragments of the human c-myc promoter were inserted upstream of luciferase reporter genes and assayed for responsiveness to inducible MycER activation in Rat-1 fibroblasts. We found four- to fivefold suppression of a c-myc P2 minimal promoter fragment upon induction of wild-type MycER protein activity, while induction of a mutant MycER protein lacking amino acids 106 to 143 required for Myc autosuppression failed to elicit this response. This assay is physiologically significant, as it reflects Myc autosuppression of the endogenous c-myc gene with regard to kinetics, dose dependency, cell type specificity, and c-Myc functional domains. Analysis of mutations within the P2 minimal promoter indicated that the cis components of Myc autosuppression could not be ascribed to any known protein-binding motifs. In addition, to address the trans factors required for Myc negative autoregulation, we expressed MycEG and MaxEG leucine zipper dimerization mutants in Rat-1 cells and found that Myc-Max heterodimerization is obligatory for Myc autosuppression. Two models for the Myc autosuppression mechanism are discussed.